Sample records for synthesis revised structure

  1. Total Synthesis and Structural Revision of Antibiotic CJ-16,264.

    PubMed

    Nicolaou, K C; Shah, Akshay A; Korman, Henry; Khan, Tabrez; Shi, Lei; Worawalai, Wisuttaya; Theodorakis, Emmanuel A

    2015-08-03

    The total synthesis and structural revision of antibiotic CJ-16,264 is described. Starting with citronellal, the quest for the target molecule featured a novel bis-transannular Diels-Alder reaction that casted stereoselectively the decalin system and included the synthesis of six isomers before demystification of its true structure. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Survey of marine natural product structure revisions: a synergy of spectroscopy and chemical synthesis

    PubMed Central

    Suyama, Takashi L.; Gerwick, William H.; McPhail, Kerry L.

    2011-01-01

    The structural assignment of new natural product molecules supports research in a multitude of disciplines that may lead to new therapeutic agents and or new understanding of disease biology. However, reports of numerous structural revisions, even of recently elucidated natural products, inspired the present survey of techniques used in structural misassignments and subsequent revisions in the context of constitutional or configurational errors. Given the comparatively recent development of marine natural products chemistry, coincident with the modern spectroscopy, it is of interest to consider the relative roles of spectroscopy and chemical synthesis in the structure elucidation and revision of those marine natural products which were initially misassigned. Thus, a tabulated review of all marine natural product structural revisions from 2005 to 2010 is organized according to structural motif revised. Misassignments of constitution are more frequent than perhaps anticipated by reliance on HMBC and other advanced NMR experiments, especially considering the full complement of all natural products. However, these techniques also feature prominently in structural revisions, specifically of marine natural products. Nevertheless, as is the case for revision of relative and absolute configuration, total synthesis is a proven partner for marine, as well as terrestrial, natural products structure elucidation. It also becomes apparent that considerable ‘detective work’ remains in structure elucidation, in spite of the spectacular advances in spectroscopic techniques. PMID:21715178

  3. Bioinspired total synthesis and structural revision of yuremamine, an alkaloid from the entheogenic plant Mimosa tenuiflora.

    PubMed

    Calvert, Matthew B; Sperry, Jonathan

    2015-04-11

    Guided by a biosynthetic hypothesis, a serendipitous total synthesis of yuremamine has resulted in its structural revision from the putative pyrroloindole (1) to the flavonoidal indole (2), which was initially proposed as a biosynthetic intermediate.

  4. A Minimalist NMR Approach for the Structural Revision of Mucoxin

    PubMed Central

    Yan, Jun; Garzan, Atefeh; Narayan, Radha S.

    2011-01-01

    In an attempt to revise the structural assignment of mucoxin, and faced with 64 diastereomeric possibilities, we resorted to the synthesis of truncated structures that contained the core stereochemical sites. Twelve stereochemical analogues were synthesized, their 1H and 13C NMR spectra were analyzed and four recurring stereochemical trends were distilled from the data. Applying the observed trends to the diastereomeric population pared the possible choices for the correct structure of mucoxin from 64 to 4. Synthesis of these analogues led to the identification of the correct structure of mucoxin. PMID:21089037

  5. Total synthesis and structural revision of the marine macrolide neopeltolide.

    PubMed

    Custar, Daniel W; Zabawa, Thomas P; Scheidt, Karl A

    2008-01-23

    The total synthesis and structural revision of the marine natural product neopeltolide is reported. The key bond-forming step involves a Lewis acid-catalyzed intramolecular cyclization to install the tetrahydropyran ring and the macrocycle simultaneously. This type of cyclization is the first of its kind and assembles the carbon backbone of the natural product efficiently. The synthesis of the reported structure revealed differences in the data between the natural and synthetic material. After significant investigation, the diastereomeric molecule with the C11 and C13 configurations inverted was synthesized using the initial route. This compound matches the data reported for neopeltolide (1H, 13C, HRMS, IR, NOESY, [alpha]), thereby establishing the correct overall structure for this potent macrolide natural product, including the relative and absolute stereochemistry.

  6. Chemical and Biological Studies of Nakiterpiosin and Nakiterpiosinone

    PubMed Central

    Gao, Shuanhu; Wang, Qiaoling; Huang, Lily Jun-Shen; Lum, Lawrence; Chen, Chuo

    2009-01-01

    Nakiterpiosin and nakiterpiosinone are two related C-nor-D-homosteroids isolated from the sponge Terpios hoshinota that show promise as anti-cancer agents. We have previously described the asymmetric synthesis and the revision of the relative configuration of nakiterpiosin. We now provide detailed information on the stereochemical analysis that supports our structure revision and the synthesis of the originally proposed and revised nakiterpiosin. In addition, we herein describe a refined approach for the synthesis of nakiterpiosin, the first synthesis of nakiterpiosinone, and preliminary mechanistic studies of nakiterpiosin's action in mammalian cells. Cells treated with nakiterpiosin exhibit compromised formation of the primary cilium, an organelle that functions as an assembly point for components of the Hedgehog signal transduction pathway. We provide evidence that the biological effects exhibited by nakiterpiosin are mechanistically distinct from those of well-established anti-mitotic agents such as taxol. Nakiterpiosin may be useful as an anti-cancer agent in those tumors resistant to existing anti-mitotic agents and those dependent on Hedgehog pathway responses for growth. PMID:20000429

  7. Biomimetic Synthesis of Macahydantoins A and B from Lepidium meyenii, and Structure Revision of Macahydantoin B as a Class of Thiohydantoin with a 4-Methyl-hexahydropyrrolo[1,2-c]imidazole Skeleton.

    PubMed

    Zhou, Min; Ma, Hang-Ying; Xing, Huan-Huan; Li, Ping; Li, Gan-Peng; Geng, Hui-Chun; Hu, Qiu-Fen; Yang, Guang-Yu

    2017-09-15

    Phytochemical investigation on Lepidium meyenii led to the discovery of macahydantoin C (3), a new thiohydantoin with a 1,3-diazabicyclo[3.3.1]nonane core, the spectral properties of which indicate a potential structural misassignment of its previously reported analogue, macahydantoin B (2a). To probe this hypothesis, a concise, scalable, and biomimetic synthesis of the originally proposed 2a and its revised structure (2b) was efficiently accomplished using the modified Edman degradation as the key step from commercially available materials in 65% (three steps) and 52% (three steps) overall yields, respectively. These synthetic endeavors undoubtedly reassigned the structure of macahydantoin B as an unreported type of thiohydantoin featuring a 4-methyl-hexahydropyrrolo[1,2-c]imidazole scaffold.

  8. Total synthesis and structural revision of TMG-chitotriomycin, a specific inhibitor of insect and fungal beta-N-acetylglucosaminidases.

    PubMed

    Yang, You; Li, Yao; Yu, Biao

    2009-09-02

    TMG-chitotriomycin, a potent and selective inhibitor of the beta-N-acetylglucosaminidases that possesses an unique N,N,N-trimethyl-d-glucosamine (TMG) residue, is revised to be the TMG-beta-(1-->4)-chitotriose instead of the originally proposed alpha-anomer via its total synthesis, for which a highly convergent approach was developed in which the sterically demanding (1-->4)-glycosidic linkages are efficiently constructed by the Au(I)-catalyzed glycosylation protocol with glycosyl o-hexynylbenzoates as donors.

  9. Structural Amendment and Stereoselective Synthesis of Mutisianthol.

    PubMed

    Ho, Tse-Lok; Lee, Kwang-Yuan; Chen, Chun-Kuei

    1997-05-16

    cis-1-(5-Acetoxy-3,6-dimethyl-1-indanyl)-2-methyl-1-propene synthesized from 3,6-dimethyl-1-indanone was found to be different from mutisianthol by spectral comparison. The presence of a high-field signal in the NMR spectrum of the final product and various intermediates, characteristic of the cis-1,3-dialkylindanes but absent in the spectrum of the natural terpene, suggests a revision of the structure of mutisianthol to the trans isomer. The trans-indane which was subsequently obtained indeed exhibits data fully agreeable with mutisianthol. A similar stereochemical revision for jungianol is also indicated.

  10. Pd-catalyzed arylation reactions with phenol diazonium salts: application in the synthesis of diarylheptanoids.

    PubMed

    Schmidt, Bernd; Hölter, Frank; Kelling, Alexandra; Schilde, Uwe

    2011-05-06

    The first total synthesis of the natural product (3S,7R)-5,6-dehydro-de-O-methyl centrolobine and various analogues is reported, using a highly regio- and diastereoselective Mizoroki-Heck reaction of phenol diazonium salts and enantiopure dihydropyrans. The assigned relative configuration was confirmed by single-crystal X-ray structure analysis, but a revision of the absolute configuration is proposed based on polarimetric measurement. © 2011 American Chemical Society

  11. Silent cries, dancing tears: the metapsychology of art revisited/revised.

    PubMed

    Aragno, Anna

    2011-04-01

    Against the backdrop of a broad survey of the literature on applied psychoanalysis, a number of concepts underpinning the metapsychology of art are revisited and revised: sublimation; interrelationships between primary and secondary processes; symbolization; "fantasy"; and "cathexis." Concepts embedded in dichotomous or drive/energic contexts are examined and reformulated in terms of a continuum of semiotic processes. Freudian dream structure is viewed as a biological/natural template for nonrepressive artistic forms of sublimation. The synthesis presented proposes a model of continuous rather than discontinuous processes, in a nonenergic, biosemiotic metatheoretical framework.

  12. Structure Reassignment and Synthesis of Jenamidines A1/A2, Synthesis of (+)-NP25302, and Formal Synthesis of SB-311009 Analogues

    PubMed Central

    Duvall, Jeremy R.; Wu, Fanghui; Snider, Barry B.

    2008-01-01

    The proposed structures of jenamidines A, B, and C (1−3) were revised to jenamidines A1/A2, B1/B2, and C (8-10). Jenamidines A1/A2 (8) were synthesized from activated proline derivative 43 by conversion to 26 in two steps and 50% overall yield. Acylation of 26 with acid chloride 38d gave 39d, which was deprotected with TFA and then mild base to give 8 in 45% yield from 26. (−)-trans-2,5-Dimethylproline ethyl ester (49) was prepared by the enantioselective Michael reaction of ethyl 2-nitropropionate (51) and methyl vinyl ketone (50) using modified dihydroquinine 60 as the catalyst. Further elaboration converted 49 to natural (+)-NP25302 (12). A Wittig reaction of proline NCA (76) with ylide 79 gave 72 as a 9/1 E/Z mixture in 27% yield completing a one step formal synthesis of SB-311009 analogues. PMID:17064037

  13. Structural Ceramic Nanocomposites: A Review of Properties and Powders’ Synthesis Methods

    PubMed Central

    Palmero, Paola

    2015-01-01

    Ceramic nanocomposites are attracting growing interest, thanks to new processing methods enabling these materials to go from the research laboratory scale to the commercial level. Today, many different types of nanocomposite structures are proposed in the literature; however, to fully exploit their exceptional properties, a deep understanding of the materials’ behavior across length scales is necessary. In fact, knowing how the nanoscale structure influences the bulk properties enables the design of increasingly performing composite materials. A further key point is the ability of tailoring the desired nanostructured features in the sintered composites, a challenging issue requiring a careful control of all stages of manufacturing, from powder synthesis to sintering. This review is divided into four parts. In the first, classification and general issues of nanostructured ceramics are reported. The second provides basic structure–property relations, highlighting the grain-size dependence of the materials properties. The third describes the role of nanocrystalline second-phases on the mechanical properties of ordinary grain sized ceramics. Finally, the fourth part revises the mainly used synthesis routes to produce nanocomposite ceramic powders, underlining when possible the critical role of the synthesis method on the control of microstructure and properties of the sintered ceramics. PMID:28347029

  14. Revising the magnetic structure and dynamics of Yttrium Iron Garnet

    NASA Astrophysics Data System (ADS)

    Princep, Andrew; Boothroyd, Andrew; Ewings, Russell; Ward, Simon; Dubs, Carsten

    Yttrium iron garnet (YIG) is the `miracle material' of microwave magnetics. Since its synthesis by Geller and Gilleo in 1957, it is widely acknowledged to have contributed more to the understanding of electronic spin-wave and magnon dynamics than any other substance. Its astonishingly narrow excitation linewidth allows magnon propagation to be observed over centimetre distances, making it both a superior model system for the experimental study of fundamental aspects of microwave magnetic dynamics and an ideal platform for the development of microwave magnetic technologies. Our experiments on a large, pristine single crystal at the ISIS facility using both diffraction and time-of-flight spectroscopy have provided new results on both the magnetic structure and the excitation spectrum, which revise nearly 60 years of scientific research and will be essential insights for the fledgling scientific field of Magnonics. EPSRC, UK.

  15. Divergent Synthesis of Revised Apratoxin E, 30-epi-Apratoxin E, and 30S/30R-Oxoapratoxin E.

    PubMed

    Mao, Zhuo-Ya; Si, Chang-Mei; Liu, Yi-Wen; Dong, Han-Qing; Wei, Bang-Guo; Lin, Guo-Qiang

    2017-10-20

    In this report, originally proposed apratoxin E (30S-7), revised apratoxin E (30R-7), and (30S)/(30R)-oxoapratoxin E (30S)-38/(30R)-38 were efficiently prepared by two synthetic methods. The chiral lactone 10, recycled from the degradation of saponin glycosides, was utilized to prepare the key nonpeptide fragment 9. Our alternative convergent assembly strategy was applied to the divergent synthesis of revised apratoxin E and its three analogues. Moreover, ring-closing metathesis (RCM) was for the first time found to be an efficient strategy for the macrocyclization of apratoxins.

  16. Amino acid–based surfactants: New antimicrobial agents.

    PubMed

    Pinazo, A; Manresa, M A; Marques, A M; Bustelo, M; Espuny, M J; Pérez, L

    2016-02-01

    The rapid increase of drug resistant bacteria makes necessary the development of new antimicrobial agents. Synthetic amino acid-based surfactants constitute a promising alternative to conventional antimicrobial compounds given that they can be prepared from renewable raw materials. In this review, we discuss the structural features that promote antimicrobial activity of amino acid-based surfactants. Monocatenary, dicatenary and gemini surfactants that contain different amino acids on the polar head and show activity against bacteria are revised. The synthesis and basic physico-chemical properties have also been included.

  17. Total Synthesis of Purported Cephalosporolides H and I, Penisporolide B, and Their Stereoisomers.

    PubMed

    Wang, Jian; Tong, Rongbiao

    2016-05-20

    Development of a unified, bioinspired synthetic strategy to access four possible diastereomers of unique 2,2-dimethyl-[5,5]-spiroacetal-cis-fused-γ-lactone (Me2SAFL) is reported, featuring pyridinium chlorochromate (PCC)-promoted oxidative ring expansion of β-hydroxy cyclic ethers and dehydrative ring-contraction rearrangement of 10-membered lactones. Synthetic utility of this strategy was demonstrated by total syntheses of 12 Me2SAFLs, corresponding to the purported cephalosporolide H (CesH), cephalosporolide I (CesI), and penisporolide B (PenB) and their possible diastereomers. Comprehensive NMR data analysis suggested that the tricyclic Me2SAFL core of CesH, CesI, and PenB should be revised to the same relative (3R*, 4R*, 6S*, 9R*) configuration and that the side chains required an unknown constitutional structure revision.

  18. Processing and validation of JEFF-3.1.1 and ENDF/B-VII.0 group-wise cross section libraries for shielding calculations

    NASA Astrophysics Data System (ADS)

    Pescarini, M.; Sinitsa, V.; Orsi, R.; Frisoni, M.

    2013-03-01

    This paper presents a synthesis of the ENEA-Bologna Nuclear Data Group programme dedicated to generate and validate group-wise cross section libraries for shielding and radiation damage deterministic calculations in nuclear fission reactors, following the data processing methodology recommended in the ANSI/ANS-6.1.2-1999 (R2009) American Standard. The VITJEFF311.BOLIB and VITENDF70.BOLIB finegroup coupled n-γ (199 n + 42 γ - VITAMIN-B6 structure) multi-purpose cross section libraries, based on the Bondarenko method for neutron resonance self-shielding and respectively on JEFF-3.1.1 and ENDF/B-VII.0 evaluated nuclear data, were produced in AMPX format using the NJOY-99.259 and the ENEA-Bologna 2007 Revision of the SCAMPI nuclear data processing systems. Two derived broad-group coupled n-γ (47 n + 20 γ - BUGLE-96 structure) working cross section libraries in FIDO-ANISN format for LWR shielding and pressure vessel dosimetry calculations, named BUGJEFF311.BOLIB and BUGENDF70.BOLIB, were generated by the revised version of SCAMPI, through problem-dependent cross section collapsing and self-shielding from the cited fine-group libraries. The validation results on the criticality safety benchmark experiments for the fine-group libraries and the preliminary validation results for the broad-group working libraries on the PCA-Replica and VENUS-3 engineering neutron shielding benchmark experiments are reported in synthesis.

  19. 20th Aerospace Mechanisms Symposium. Revised

    NASA Technical Reports Server (NTRS)

    1986-01-01

    The proceedings of the 20th Aerospace Mechanisms Symposium, hosted by the NASA Lewis Research Center, Cleveland, Ohio, on May 7-9, 1986, is documented herein. During the 3 days, 23 technical papers were presented by experts from the United States and Western Europe. A panel discussion by an International group of experts on future directions In mechanisms was also presented; this discussion, however, is not documented herein. The technical topics addressed included deployable structures, electromagnetic devices, tribology, thermal/mechanical/hydraulic actuators, latching devices, positioning mechanisms, robotic manipulators, and computerized mechanisms synthesis.

  20. Exploration of mild copper-mediated coupling of organotrifluoroborates in the synthesis of thiirane-based inhibitors of matrix metalloproteinases.

    PubMed

    Testero, Sebastian A; Bouley, Renee; Fisher, Jed F; Chang, Mayland; Mobashery, Shahriar

    2011-05-01

    The copper-mediated and non-basic oxidative cross-coupling of organotrifluoroborates with phenols was applied to elaboration of the structures of thiirane-based inhibitors of matrix metalloproteinases. By revision of the synthetic sequence to allow this cross-coupling as the final step, and taking advantage of the neutral nature of organotrifluoroborate cross-coupling, a focussed series of inhibitors showing aryloxy and alkenyloxy replacement of the phenoxy substituent was prepared. This reaction shows exceptional promise as an alternative to the classic copper-mediated but strongly basic Ullmann reaction, for the diversification of ether segments within base-labile lead structures. Copyright © 2010 Elsevier Ltd. All rights reserved.

  1. Comprehensive Truck Size and Weight (TS&W) Study. Phase 1-synthesis, working paper 12 : energy conservation and truck size and weight regulations

    DOT National Transportation Integrated Search

    2013-01-01

    This project consisted of the development of a revision of the SAE J2735 Dedicated Short Range Communications (DSRC) Message Set Dictionary, published 2009-11-19. This revision will be submitted, at the end of this project to the Society of Automotiv...

  2. An Application of Fuzzy Theory to Technical Competency Analysis for the Entry-Level Electronic Technician.

    ERIC Educational Resources Information Center

    Chang, Liang-Te; And Others

    A study was conducted to develop the electronic technical competencies of duty and task analysis by using a revised DACUM (Developing a Curriculum) method, a questionnaire survey, and a fuzzy synthesis operation. The revised DACUM process relied on inviting electronics trade professionals to analyze electronic technology for entry-level…

  3. Revision of the structures of citrifolinin A, citrifolinoside, yopaaoside A, yopaaoside B, and morindacin, iridoids from Morinda citrifolia L. and Morinda coreia Ham.

    PubMed

    Schripsema, Jan; Caprini, Geisa P; Dagnino, Denise

    2006-11-09

    [Structure: see text] Citrifolin A was revised to dehydromethoxygaertneroside (2). Citrifolinoside and yopaaoside A were found to be identical, and their structures were revised to the new structure dehydroepoxymethoxygaertneroside (5). Yopaaoside B was revised to citrifolinoside A (9), and morindacin was revised to borreriagenin (11).

  4. O-Alkylated heavy atom carbohydrate probes for protein X-ray crystallography: Studies towards the synthesis of methyl 2-O-methyl-L-selenofucopyranoside.

    PubMed

    Sommer, Roman; Hauck, Dirk; Varrot, Annabelle; Imberty, Anne; Künzler, Markus; Titz, Alexander

    2016-01-01

    Selenoglycosides are used as reactive glycosyl donors in the syntheses of oligosaccharides. In addition, such heavy atom analogs of natural glycosides are useful tools for structure determination of their lectin receptors using X-ray crystallography. Some lectins, e.g., members of the tectonin family, only bind to carbohydrate epitopes with O-alkylated ring hydroxy groups. In this context, we report the first synthesis of an O -methylated selenoglycoside, specifically methyl 2- O -methyl-L-selenofucopyranoside, a ligand of the lectin tectonin-2 from the mushroom Laccaria bicolor . The synthetic route required a strategic revision and further optimization due to the intrinsic lability of alkyl selenoglycosides, in particular for the labile fucose. Here, we describe a successful synthetic access to methyl 2- O -methyl-L-selenofucopyranoside in 9 linear steps and 26% overall yield starting from allyl L-fucopyranoside.

  5. Reframing developmental biology and building evolutionary theory's new synthesis.

    PubMed

    Tauber, Alfred I

    2010-01-01

    Gilbert and Epel present a new approach to developmental biology: embryogenesis must be understood within the full context of the organism's environment. Instead of an insular embryo following a genetic blueprint, this revised program maintains that embryogenesis is subject to inputs from the environment that generate novel genetic variation with dynamic consequences for development. Beyond allelic variation of structural genes and of regulatory loci, plasticity-derived epigenetic variation completes the triad of the major types of variation required for evolution. Developmental biology and ecology, disciplines that have previously been regarded as distinct, are presented here as fully integrated under the rubric of "eco-devo," and from this perspective, which highlights how the environment not only selects variation, it helps construct it, another synthesis with evolutionary biology must also be made, "eco-evo-devo." This second integration has enormous implications for expanding evolution theory, inasmuch as the Modern Synthesis (Provine 1971), which combined classical genetics and Darwinism in the mid-20th century, did not account for the role of development in evolution. The eco-evo-devo synthesis thus portends a major theoretical inflection in evolutionary biology. Following a description of these scientific developments, comment is offered as to how this new integrated approach might be understood within the larger shifts in contemporary biology.

  6. Using Intentional Development of Research Skills as a Framework for Curriculum Reform

    NASA Astrophysics Data System (ADS)

    Peterson, V. L.; Lord, M. L.

    2008-12-01

    We advocate that geoscience departmental or community discussions related to curriculur revision or accreditation should be considered within a framework that clearly and intentionally develops research and professional skills throughout the curricular structure. Among the primary qualities sought by geoscience employers and graduate schools are graduates with strong research, critical thinking, field, communication, and people/team skills. While these should be the hallmark of a liberally educated graduate, we think it is imperative to explicitly develop and assess these skills as part of the same curricular framework used for organizing essential content. Though many organizations and authors have argued about the importance and effectiveness of undergraduate research as a means to develop higher level skill sets, discussions of geoscience accreditation or curricular revision commonly emphasize the choice of a core set of courses or content. Drummond and Markin (2008) highlight the commonalities among core geoscience courses. However, their summary, and our own experiences and program comparisons also point out diversity among successful geoscience program cores that may relate to expansion of the boundaries of our discipline, geographic factors, and/or size and character of department faculty. At Western Carolina University (WCU) and more recently at Grand Valley State University, attempts at curricular revision were initially stymied by difficulties in defining core courses. At WCU, focus on a critical skills framework helped to work through these challenges to establish a revised geology curriculum in 2000 with explicit goals to build critical thinking, reasoning, synthesis, and communication skills. To achieve these goals, investigative experiences were included in all geology courses, a senior research capstone was required, and more opportunities were created for all students to engage in out-of-class research. Numerous measures indicate programmatic and student successes, but reveal challenges that the program now seeks to improve by adding skills and assessment benchmarks to key courses at each class level. These changes are supported by a faculty with a common vision, a recent program review, and a University initiative to improve student engagement and synthesis.

  7. Synthesis of science to inform land management within the Northwest Forest Plan area

    Treesearch

    Thomas A. Spies; Peter A. Stine; Rebecca A. Gravenmier; Jonathan W. Long; Matthew J. Reilly

    2018-01-01

    The 1994 Northwest Forest Plan (NWFP) was developed to resolve debates over old-growth forests, endangered species, and timber production on federal forests in the range of the northern spotted owl. This three-volume science synthesis, which consists of 12 chapters that address various ecological and social concerns, is intended to inform forest plan revision and...

  8. Structured Head and Neck CT Angiography Reporting Reduces Resident Revision Rates.

    PubMed

    Johnson, Tucker F; Brinjikji, Waleed; Doolittle, Derrick A; Nagelschneider, Alex A; Welch, Brian T; Kotsenas, Amy L

    2018-04-12

    This resident-driven quality improvement project was undertaken to assess the effectiveness of structured reporting to reduce revision rates for afterhours reports dictated by residents. The first part of the study assessed baseline revision rates for head and neck CT angiography (CTA) examinations dictated by residents during afterhours call. A structured report was subsequently created based on templates on the RSNA informatics reporting website and critical findings that should be assessed for on all CTA examinations. The template was made available to residents through the speech recognition software for all head and neck CTA examinations for a duration of 2 months. Report revision rates were then compared with and without use of the structured template. The structured template was found to reduce revision rates by approximately 50% with 10/41 unstructured reports revised and 2/17 structured reports revised. We believe that structured reporting can help reduce reporting errors, particularly in term of typographical errors, train residents to evaluate complex examinations in a systematic fashion, and assist them in recalling critical findings on these examinations. Copyright © 2018 Elsevier Inc. All rights reserved.

  9. On the synthesis of AlPO4-21 molecular sieve by vapor phase transport method and its phase transformation to AlPO4-15 molecular sieve

    NASA Astrophysics Data System (ADS)

    Shao, Hui; Chen, Jingjing; Chen, Xia; Leng, Yixin; Zhong, Jing

    2015-04-01

    An experimental design was applied to the synthesis of AlPO4-21 molecular sieve (AWO structure) by vapor phase transport (VPT) method, using tetramethylguanidine (TMG) as the template. In this study, the effects of crystallization time, crystallization temperature, phosphor content, template content and water content in the synthesis gel were investigated. The materials obtained were characterized by X-ray diffraction, scanning electron microscopy and fourier transform infrared spectroscopy (FT-IR). Microstructural analysis of the crystal growth in vapor synthetic conditions revealed a revised crystal growth route from zeolite AlPO4-21 to AlPO4-15 in the presence of the TMG. Homogenous hexagonal prism AlPO4-21 crystals with size of 7 × 3 μm were synthesized at a lower temperature (120 °C), which were completely different from the typical tabular parallelogram crystallization microstructure of AlPO4-21 phase. The crystals were transformed into AlPO4-21 phase with higher crystallization temperature, longer crystallization time, higher P2O5/Al2O3 ratio and higher TMG/Al2O3 ratio.

  10. Newly Enacted Intent Changes to ADS-B MASPS: Emphasis on Operations, Compatibility, and Integrity

    NASA Technical Reports Server (NTRS)

    Barhydt, Richard; Warren, Anthony W.

    2002-01-01

    Significant changes to the intent reporting structure in the Minimum Aviation System Performance Standards (MASPS) for Automatic Dependent Surveillance Broadcast (ADS-B) have recently been approved by RTCA Special Committee 186. The re-structured intent formats incorporate two major changes to the current MASPS (DO-242): addition of a Target State (TS) report that provides information on the horizontal and vertical targets for the current flight segment and replacement of the current Trajectory Change Point (TCP) and TCP+1 reports with Trajectory Change (TC) reports. TC reports include expanded information about TCPs and their connecting flight segments, in addition to making provisions for trajectory conformance elements. New intent elements are designed to accommodate a greater range of intent information, better reflect operational use and capabilities of existing and future aircraft avionics, and aid trajectory synthesis and conformance monitoring systems. These elements are expected to benefit near-term and future Air Traffic Management (ATM) applications, including separation assurance, local traffic flow management, and conformance monitoring. The current MASPS revision (DO-242A) implements those intent elements that are supported by current avionics standards and data buses. Additional elements are provisioned for inclusion in future MASPS revisions (beyond DO-242A) as avionics systems are evolved.

  11. Processing of laser formed SiC powder

    NASA Technical Reports Server (NTRS)

    Haggerty, J. S.; Bowen, H. K.

    1987-01-01

    Processing research was undertaken to demonstrate that superior SiC characteristics could be achieved through the use of ideal constituent powders and careful post-synthesis processing steps. Initial research developed the means to produce approximately 1000 A uniform diameter, nonagglomerated, spherical, high purity SiC powders. Accomplishing this goal required major revision of the particle formation and growth model from one based on classical nucleation and growth to one based on collision and coalescence of Si particles followed by their carburization. Dispersions based on pure organic solvents as well as steric stabilization were investigated. Test parts were made by the colloidal pressing technique; both liquid filtration and consolidation (rearrangement) stages were modeled. Green densities corresponding to a random close packed structure were achieved. After drying, parts were densified at temperatures ranging from 1800 to 2100 C. This research program accomplished all of its major objectives. Superior microstructures and properties were attained by using powders having ideal characteristics and special post-synthesis processing procedures.

  12. Divergent synthesis of bioactive resorcinols isolated from the fruiting bodies of Hericium erinaceum: total syntheses of hericenones A, B, and I, hericenols B-D, and erinacerins A and B.

    PubMed

    Kobayashi, Shoji; Tamanoi, Hidetsugu; Hasegawa, Yuichi; Segawa, Yusuke; Masuyama, Araki

    2014-06-06

    Total syntheses of 5'- and 7'-oxidized geranyl resorcylates isolated from the fruiting bodies of Hericium erinaceum and the submerged cultures of a Stereum species were achieved. Our synthesis features derivatization of a suitably functionalized 5'-oxidized geranyl phthalide as a common intermediate, which was obtained by Stille coupling between the phthalide core and the side chain, into a series of natural products by divergent functional group manipulations. The crucial C5'-oxygen functionality was installed at the initial stage by alkylation by an α-cyano ethoxyethyl ether. From a common synthetic intermediate, eight total syntheses including hericenones A, B, and I, hericenols B-D, and erinacerins A and B were achieved (hericenol B and erinacerin B were synthesized as racemates). The structure of hericenone B established in the isolation paper was unambiguously revised as the carbonyl regioisomer at the lactam moiety.

  13. Structure-Based Design, Synthesis and Testing of Non-Peptide, Cell-Permeable, Potent Small Molecule Smac Mimetics as a New Therapy for Prostate Cancer. Revision

    DTIC Science & Technology

    2007-02-01

    from pyroglutamic acid 7 in eight steps according to a reported method.32 Hydrogenation of the double bond in 8 catalyzed by 10% Pd-C, followed by...with 70% perchloric acid and concentrated hydrochloric acid . RCH2PPh3Br + O O OMe OMe a,b O O OMe OMe R c,d O O OH OH R CHO 21a-1h 3a-3h 4a-4h Scheme...Smac to XIAP BIR3 is mediated by AVPI four amino acid residues in Smac and a well-defined surface binding groove in XIAP BIR3. While the alanine residue

  14. 78 FR 15755 - Proposed Revision to Design of Structures, Components, Equipment and Systems; Correction

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-12

    ... NUCLEAR REGULATORY COMMISSION [NRC-2013-0041] Proposed Revision to Design of Structures, Components, Equipment and Systems; Correction AGENCY: Nuclear Regulatory Commission. ACTION: Standard review... for comments of the proposed revision in Chapter 3, ``Design of Structures, Components, Equipment, and...

  15. The revised solar array synthesis computer program

    NASA Technical Reports Server (NTRS)

    1970-01-01

    The Revised Solar Array Synthesis Computer Program is described. It is a general-purpose program which computes solar array output characteristics while accounting for the effects of temperature, incidence angle, charged-particle irradiation, and other degradation effects on various solar array configurations in either circular or elliptical orbits. Array configurations may consist of up to 75 solar cell panels arranged in any series-parallel combination not exceeding three series-connected panels in a parallel string and no more than 25 parallel strings in an array. Up to 100 separate solar array current-voltage characteristics, corresponding to 100 equal-time increments during the sunlight illuminated portion of an orbit or any 100 user-specified combinations of incidence angle and temperature, can be computed and printed out during one complete computer execution. Individual panel incidence angles may be computed and printed out at the user's option.

  16. A Guide for applying a revised version of the PARIHS framework for implementation

    PubMed Central

    2011-01-01

    Background Based on a critical synthesis of literature on use of the Promoting Action on Research Implementation in Health Services (PARIHS) framework, revisions and a companion Guide were developed by a group of researchers independent of the original PARIHS team. The purpose of the Guide is to enhance and optimize efforts of researchers using PARIHS in implementation trials and evaluations. Methods Authors used a planned, structured process to organize and synthesize critiques, discussions, and potential recommendations for refinements of the PARIHS framework arising from a systematic review. Using a templated form, each author independently recorded key components for each reviewed paper; that is, study definitions, perceived strengths/limitations of PARIHS, other observations regarding key issues and recommendations regarding needed refinements. After reaching consensus on these key components, the authors summarized the information and developed the Guide. Results A number of revisions, perceived as consistent with the PARIHS framework's general nature and intent, are proposed. The related Guide is composed of a set of reference tools, provided in Additional files. Its core content is built upon the basic elements of PARIHS and current implementation science. Conclusions We invite researchers using PARIHS for targeted evidence-based practice (EBP) implementations with a strong task-orientation to use this Guide as a companion and to apply the revised framework prospectively and comprehensively. Researchers also are encouraged to evaluate its use relative to perceived strengths and issues. Such evaluations and critical reflections regarding PARIHS and our Guide could thereby promote the framework's continued evolution. PMID:21878092

  17. Confirming the Revised C-Terminal Domain of the MscL Crystal Structure

    PubMed Central

    Maurer, Joshua A.; Elmore, Donald E.; Clayton, Daniel; Xiong, Li; Lester, Henry A.; Dougherty, Dennis A.

    2008-01-01

    The structure of the C-terminal domain of the mechanosensitive channel of large conductance (MscL) has generated significant controversy. As a result, several structures have been proposed for this region: the original crystal structure (1MSL) of the Mycobacterium tuberculosis homolog (Tb), a model of the Escherichia coli homolog, and, most recently, a revised crystal structure of Tb-MscL (2OAR). To understand which of these structures represents a physiological conformation, we measured the impact of mutations to the C-terminal domain on the thermal stability of Tb-MscL using circular dichroism and performed molecular dynamics simulations of the original and the revised crystal structures of Tb-MscL. Our results imply that this region is helical and adopts an α-helical bundle conformation similar to that observed in the E. coli MscL model and the revised Tb-MscL crystal structure. PMID:18326638

  18. Synthesis of stiffened shells of revolution

    NASA Technical Reports Server (NTRS)

    Thornton, W. A.

    1974-01-01

    Computer programs for the synthesis of shells of various configurations were developed. The conditions considered are: (1) uniform shells (mainly cones) using a membrane buckling analysis, (2) completely uniform shells (cones, spheres, toroidal segments) using linear bending prebuckling analysis, and (3) revision of second design process to reduce the number of design variables to about 30 by considering piecewise uniform designs. A perturbation formula was derived and this allows exact derivatives of the general buckling load to be computed with little additional computer time.

  19. Bonding structure in amorphous carbon nitride: A spectroscopic and nuclear magnetic resonance study

    NASA Astrophysics Data System (ADS)

    Sánchez-López, J. C.; Donnet, C.; Lefèbvre, F.; Fernández-Ramos, C.; Fernández, A.

    2001-07-01

    Since the prediction of Liu and Cohen [Science 245, 841 (1989)] of the potential extraordinary mechanical properties of crystalline β-C3N4, many authors have attempted its synthesis. However, in most cases, the obtained materials are amorphous phases with a complex bonding structure. Their characterization is complicated due to the absence of a reference compound, the lack of long-range order, and the poor knowledge about their bonding structure. In this article, we present 1H, 13C, and 15N solid-state nuclear magnetic resonance (NMR) measurements for the determination of the bonding types in amorphous CNx films. NMR measurements do not require long-range order and are able to clearly identify the signals from the sp2- and sp3-bonded phases. The analysis of the data obtained by other characterization techniques, such as infrared spectroscopy, x-ray photoelectron spectroscopy, electron energy-loss spectroscopy, and x-ray absorption near-edge spectroscopy on the same sample, based on the information acquired by NMR, enables the description of a structure model for the studied amorphous-CNx phase prepared by dc-magnetron sputtering and to revise the interpretation found in the literature.

  20. A revised Self- and Family Management Framework.

    PubMed

    Grey, Margaret; Schulman-Green, Dena; Knafl, Kathleen; Reynolds, Nancy R

    2015-01-01

    Research on self- and family management of chronic conditions has advanced over the past 6 years, but the use of simple frameworks has hampered the understanding of the complexities involved. We sought to update our previously published model with new empirical, synthetic, and theoretical work. We used synthesis of previous studies to update the framework. We propose a revised framework that clarifies facilitators and barriers, processes, proximal outcomes, and distal outcomes of self- and family management and their relationships. We offer the revised framework as a model that can be used in studies aimed at advancing self- and family management science. The use of the framework to guide studies would allow for the design of studies that can address more clearly how self-management interventions work and under what conditions. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. 78 FR 19541 - Proposed Revision to Design of Structures, Components, Equipment and Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-01

    ... NUCLEAR REGULATORY COMMISSION [NRC-2013-0041] Proposed Revision to Design of Structures, Components, Equipment and Systems AGENCY: Nuclear Regulatory Commission. ACTION: Standard review plan-draft..., ``Design of Structures, Components, Equipment, and Systems;'' and the request for comment on NUREG-0800...

  2. A reliability analysis of the revised competitiveness index.

    PubMed

    Harris, Paul B; Houston, John M

    2010-06-01

    This study examined the reliability of the Revised Competitiveness Index by investigating the test-retest reliability, interitem reliability, and factor structure of the measure based on a sample of 280 undergraduates (200 women, 80 men) ranging in age from 18 to 28 years (M = 20.1, SD = 2.1). The findings indicate that the Revised Competitiveness Index has high test-retest reliability, high inter-item reliability, and a stable factor structure. The results support the assertion that the Revised Competitiveness Index assesses competitiveness as a stable trait rather than a dynamic state.

  3. Building zeolites from pre-crystallized units: nanoscale architecture.

    PubMed

    Corma, Avelino; Li, Chengeng; Moliner, Manuel

    2018-01-24

    Since the earlier descriptions by Barrer in the 40's on converting natural minerals into synthetic zeolites, the use of pre-crystallized zeolites as crucial inorganic directing agents to synthesize other crystalline zeolites with improved physico-chemical properties, has become a very intense and relevant research field, allowing the design, particularly in the last years, of new industrial catalysts. In the present review, we will highlight how the presence of some crystalline fragments in the synthesis media, such as small secondary building units (SBUs) or layered substructures, not only favors the crystallization of other zeolites presenting similar SBUs or layers, but also permits mostly controlling important parameters affecting to their catalytic activity (i.e. chemical composition, crystal size, or porosity, among others). In this sense, the recent advances on the preparation of 3-D and 2-D related zeolites through seeding and zeolite-to-zeolite transformation processes will be extensively revised, including their preparation in presence or absence of organic structure directing agents (OSDAs), with the aim of introducing general guidelines for designing more efficient future synthesis approaches for target zeolites. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Planning and Revising Written Arguments: The Effects of Two Text Structure-Based Interventions on Persuasiveness of 8th-Grade Students' Essays

    ERIC Educational Resources Information Center

    Midgette, Ekaterina; Haria, Priti

    2016-01-01

    The purpose of the study was to investigate the effects of two comprehensive argumentative writing interventions--Text Structure Instruction (TSI) and Text Structure Revision Instruction (TSRI)--on the eighth-grade students' ability to compose convincing essays that include structural elements of argumentative discourse. Both treatment groups…

  5. The Padua Inventory: Do Revisions Need Revision?

    ERIC Educational Resources Information Center

    Gonner, Sascha; Ecker, Willi; Leonhart, Rainer

    2010-01-01

    The purpose of the present study was to examine the psychometric properties, factorial structure, and validity of the Padua Inventory-Washington State University Revision and of the Padua Inventory-Revised in a large sample of patients with obsessive-compulsive disorder (n = 228) and with anxiety disorders and/or depression (n = 213). The…

  6. Charles Darwin's reputation: how it changed during the twentieth-century and how it may change again.

    PubMed

    Amundson, Ron

    2014-01-01

    Charles Darwin died in 1882. During the twentieth century his reputation varied through time, as the scientific foundation of evolutionary theory changed. Beginning the century as an intellectual hero, he soon became a virtual footnote as experimental approaches to evolution began to develop. As the Modern Synthesis developed his reputation began to rise again until eventually he was identified as a founding father of the Modern Synthesis itself. In the meantime, developmental approaches to evolution began to challenge certain aspects of the Modern Synthesis. Synthesis authors attempted to refute the relevance of development by methodological arguments, some of them indirectly credited to Darwin. By the end of the century, molecular genetics had given new life to development approaches to evolution, now called evo devo. This must be seen as a refutation of the aforesaid methodological arguments of the Modern Synthesis advocates. By the way, we can also see now how the historiography that credited Darwin with the Synthesis was in error. In conclusion, one more historical revision is suggested. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Synthesis and evaluation of lightweight concrete research relevant to the AASHTO LRFD bridge design specifications : potential revisions for definition and mechanical properties.

    DOT National Transportation Integrated Search

    2012-11-01

    Much of the fundamental basis for the current lightweight concrete provisions in the AASHTO LRFD Bridge : Design Specifications is based on research of lightweight concrete (LWC) from the 1960s. The LWC that was : part of this research used tradition...

  8. Native Americans of California and Nevada. Revised Edition.

    ERIC Educational Resources Information Center

    Forbes, Jack D.

    This book is designed to provide an introductory synthesis of the history and sociocultural evolution of Native American peoples in the Far West, with strong emphasis on California and Nevada. The book focuses particularly on those historical and cultural experiences likely to have contributed to the present conditions of Native communities and…

  9. An Evaluation of the Technical Adequacy of a Revised Measure of Quality Indicators of Transition

    ERIC Educational Resources Information Center

    Morningstar, Mary E.; Lee, Hyunjoo; Lattin, Dana L.; Murray, Angela K.

    2016-01-01

    This study confirmed the reliability and validity of the Quality Indicators of Exemplary Transition Programs Needs Assessment-2 (QI-2). Quality transition program indicators were identified through a systematic synthesis of transition research, policies, and program evaluation measures. To verify reliability and validity of the QI-2, we…

  10. DOE Chair of Excellence in Environmental Disciplines-Final Technical Report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kurunganty, Sastry; Loran, Roberto; Roque-Malherbe, Rolando

    The report Massie Chair of Excellence Program at Universidad del Turabo, contract DE-FG02-95EW12610, during the period of 9/29/1995 to 9/29/2011. The initial program aims included development of academic programs in the Environmental Sciences and Engineering, and Research and Development focused initially on environmentally friendly processes and later revised also include: renewable energy and international cooperation. From 1995 -2005, the Program at UT lead the establishment of the new undergraduate program in electrical engineering at the School of Engineering (SoE), worked on requirements to achieve ABET accreditation of the SoE B.S. Mechanical Engineering and B.S. Electrical Engineering programs, mentored junior faculty,more » taught undergraduate courses in electrical engineering, and revised the electrical engineering curriculum. Engineering undergraduate laboratories were designed and developed. The following research sub-project was developed: Research and development of new perovskite-alumina hydrogen permeable asymmetrical nanostructured membranes for hydrogen purification, and extremely high specific surface area silica materials for hydrogen storage in the form of ammonia, Dr. Rolando Roque-Malherbe Subproject PI, Dr. Santander Nieto and Mr. Will Gómez Research Assistants. In 2006, the Massie Chair of Excellence Program was transferred to the National Nuclear Security Agency, NNSA and DNN. DoE required a revised proposal aligned with the priorities of the Administration. The revised approved program aims included: (1) Research (2) Student Development: promote the development of minority undergraduate and graduate students through research teams, internships, conferences, new courses; and, (3) Support: (a) Research administration and (b) Dissemination through international conferences, the UT Distinguished Lecturer Series in STEM fields and at the annual Universidad del Turabo (UT) Researchers Conference. Research included: Sub-Project 1: Synthesis and Characterization of low Refractive Index Aerogel Silica for Cherenkov Counters- Dr. Rolando Roque-Malherbe Sub-project PI, Dr. Jose Duconge Sub-project Co-PI, Dr. Santander Nieto Assistant Researcher, Francisco Diaz and Carlos Neira Associate Researchers. The initial aim of this sub-project was changed to the synthesis and characterization of extremely high specific surface area aerogel silica for gas storage. A high specific surface area silica gel that has applications in gas drying, cleaning operation useful in nuclear industry in process was developed. Sub-Project 2: Investigation Study of Magnetic and Electronic Transport Properties at Material Interfaces in Magnetic Multilayer Heterostructure using Gd. – Dr. Yazan Hijazi, Sub-project Co-PI. UT developed the capability and infrastructure to produce high quality thin-film magnetic films and magnetic multilayer structures with fine control over film quality and thickness using sputter deposition capability to perform in-house electric and magnetic characterization of these films. The research experimentally quantified the effect of Gd incorporation within the magnetic multilayer structure and produce magnetic media with exchanged decoupled multilevel magnetic anisotropy. From September 2006 to September 2011 the Massie Chair produced nineteen (19) publications, (including 3 books), five (5) presentations and three (3) international conferences abstracts. A total of fourteen (14) undergraduates and (6) graduate students acquired research experience. Two Ph.D. students presented their dissertations on topics related to nuclear energy and graduated as follows: María Cotto (May 2009) and Eric Calderón (May 2011). Five of the participating undergraduate students graduated: Ramon Polanco (BSME, May 2009), Jason Pérez (BSEE, May 2008), Rafael Colón (BSME, May 2008), Jessenia Marfisi (BS Chemistry, May 2008). Eleven (11) students were sent to National Laboratories (LANL, SNL and LLNL), NNSA and DoE facilities for summer internships. Twenty eight (28) undergraduate students participated in Summer Internships (2010, 2011) at the Puerto Rico Energy Center (PREC). Four international energy symposiums were held aligned with the DoE and the NNSA missions and dissemination of Massie Chair research activities (660 attendees). Academic programs developed or revised under advice of the Massie Chair: Ph.D. in Environmental Sciences (revised); MSc in Environmental Sciences (revised); MSc in Mechanical Engineering with concentration in Alternative Energy (new); BS in Industrial Management & Engineering (revised to fulfill the ABET requirements); BS in Civil Engineering including an environmental option (new); BS in Electrical Engineering (revised); and, Associate in Renewable Energy (new). The Puerto Rico Energy Center (PREC) was designed and developed under the Massie Chair initiative. Thirty-three (33) proposals were developed and submitted during the period of which 12 were approved in the amount of $ $1,931,306.« less

  11. The Sport Concussion Assessment Tool 5th Edition (SCAT5): Background and rationale.

    PubMed

    Echemendia, Ruben J; Meeuwisse, Willem; McCrory, Paul; Davis, Gavin A; Putukian, Margot; Leddy, John; Makdissi, Michael; Sullivan, S John; Broglio, Steven P; Raftery, Martin; Schneider, Kathryn; Kissick, James; McCrea, Michael; Dvořák, Jiří; Sills, Allen K; Aubry, Mark; Engebretsen, Lars; Loosemore, Mike; Fuller, Gordon; Kutcher, Jeffrey; Ellenbogen, Richard; Guskiewicz, Kevin; Patricios, Jon; Herring, Stanley

    2017-06-01

    This paper presents the Sport Concussion Assessment Tool 5th Edition (SCAT5), which is the most recent revision of a sport concussion evaluation tool for use by healthcare professionals in the acute evaluation of suspected concussion. The revision of the SCAT3 (first published in 2013) culminated in the SCAT5. The revision was based on a systematic review and synthesis of current research, public input and expert panel review as part of the 5th International Consensus Conference on Concussion in Sport held in Berlin in 2016. The SCAT5 is intended for use in those who are 13 years of age or older. The Child SCAT5 is a tool for those aged 5-12 years, which is discussed elsewhere. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  12. Revised Space Groups for Three Molybdenum(V) Phosphate Compounds

    NASA Astrophysics Data System (ADS)

    Leclaire, A.; Borel, M. M.; Guesdon, A.; Marsh, Richard E.

    2001-06-01

    The space groups of three previously described Mo(V) phosphate structures are revised. (1) δ-KMo2P3O13, originally reported as triclinic, Poverline1, is revised to monoclinic, C2/c; it is identical to the compound previously identified as K4Mo8P12O52. (2) The compound formulated as [Mo12CdP8O50(OH)12]Cd [N(CH3)4]2(H3O)6·5H2O, originally described as monoclinic, Pn, is revised to P21/n (also monoclinic). (3) Rb3O2(MoO)4(PO4)4, originally reported as orthorhombic, C2221, is revised to tetragonal, P43212. The general descriptions of the structures are unchanged; however, for compound 2 the revision involves the addition of a center of symmetry and, as a result, there are significant changes in the interatomic distances and angles.

  13. Revising the Child and Adolescent Perfectionism Scale: A Test of the Four-Factor Structure in a Chinese Sample

    ERIC Educational Resources Information Center

    Yang, Hongfei; Hong, Chaoqin; Tao, Xiaodan; Zhu, Lingyi

    2015-01-01

    This study examined the structure, reliability, and validity of the revised Chinese version of the Child and Adolescent Perfectionism Scale (N = 933). The results confirmed the four-factor structure of the Chinese version of the Child and Adolescent Perfectionism Scale. Implications, limitations, and suggestions for future research are provided.

  14. Integrated Science Assessment (ISA) for Oxides of Nitrogen, Oxides of Sulfur and Particulate Matter Ecological Criteria (Second External Review Draft)

    EPA Science Inventory

    This draft Integrated Science Assessment (ISA) represents a concise synthesis and evaluation of the most policy-relevant science and will ultimately provide the scientific bases for EPA’s decision on retaining or revising the current secondary standards for NO2, SO

  15. Synthesis and evaluation of lightweight concrete research relevant to the AASHTO LRFD bridge design specifications : identification of articles for further evaluation and potential revision.

    DOT National Transportation Integrated Search

    2012-11-01

    Much of the fundamental basis for the current lightweight concrete provisions in the AASHTO LRFD Bridge : Design Specifications is based on research of lightweight concrete (LWC) from the 1960s. The LWC that was : part of this research used tradition...

  16. The encyclopedia of southern Appalachian forest ecosystems: A prototype of an online scientific knowledge management system

    Treesearch

    Deborah K. Kennard; H. Michael Rauscher; Patricia A. Flebbe; Daniel L. Schmoldt; William G. Hubbard; J. Bryan Jordin; William Milnor

    2003-01-01

    The Encyclopedia of Southern Appalachian Forest Ecosystems (ESAFE), a hyperdocument-based encyclopedia system available on the Internet, provides an organized synthesis of existing research on the management and ecology of Southern Appalachian forests ecosystems. The encyclopedia is dynamic, so that new or revised content can be submitted directly through the Internet...

  17. Modeling-Oriented Assessment in K-12 Science Education: A Synthesis of Research from 1980 to 2013 and New Directions

    ERIC Educational Resources Information Center

    Namdar, Bahadir; Shen, Ji

    2015-01-01

    Scientific modeling has been advocated as one of the core practices in recent science education policy initiatives. In modeling-based instruction (MBI), students use, construct, and revise models to gain scientific knowledge and inquiry skills. Oftentimes, the benefits of MBI have been documented using assessments targeting students' conceptual…

  18. Evolutionary conservation of codon optimality reveals hidden signatures of cotranslational folding.

    PubMed

    Pechmann, Sebastian; Frydman, Judith

    2013-02-01

    The choice of codons can influence local translation kinetics during protein synthesis. Whether codon preference is linked to cotranslational regulation of polypeptide folding remains unclear. Here, we derive a revised translational efficiency scale that incorporates the competition between tRNA supply and demand. Applying this scale to ten closely related yeast species, we uncover the evolutionary conservation of codon optimality in eukaryotes. This analysis reveals universal patterns of conserved optimal and nonoptimal codons, often in clusters, which associate with the secondary structure of the translated polypeptides independent of the levels of expression. Our analysis suggests an evolved function for codon optimality in regulating the rhythm of elongation to facilitate cotranslational polypeptide folding, beyond its previously proposed role of adapting to the cost of expression. These findings establish how mRNA sequences are generally under selection to optimize the cotranslational folding of corresponding polypeptides.

  19. Using framework-based synthesis for conducting reviews of qualitative studies.

    PubMed

    Dixon-Woods, Mary

    2011-04-14

    Framework analysis is a technique used for data analysis in primary qualitative research. Recent years have seen its being adapted to conduct syntheses of qualitative studies. Framework-based synthesis shows considerable promise in addressing applied policy questions. An innovation in the approach, known as 'best fit' framework synthesis, has been published in BMC Medical Research Methodology this month. It involves reviewers in choosing a conceptual model likely to be suitable for the question of the review, and using it as the basis of their initial coding framework. This framework is then modified in response to the evidence reported in the studies in the reviews, so that the final product is a revised framework that may include both modified factors and new factors that were not anticipated in the original model. 'Best fit' framework-based synthesis may be especially suitable in addressing urgent policy questions where the need for a more fully developed synthesis is balanced by the need for a quick answer. Please see related article: http://www.biomedcentral.com/1471-2288/11/29.

  20. Children's application of simultaneous and successive processing in inductive and deductive reasoning problems: Implications for developing scientific reasoning skills

    NASA Astrophysics Data System (ADS)

    Watters, James J.; English, Lyn D.

    The research reported in this article was undertaken to obtain a better understanding of problem solving and scientific reasoning in 10-year-old children. The study involved measuring children's competence at syllogistic reasoning and in solving a series of problems requiring inductive reasoning. Children were also categorized on the basis of levels of simultaneous and successive synthesis. Simultaneous and successive synthesis represent two dimensions of information processing identified by Luria in a program of neuropsychological research. Simultaneous synthesis involves integration of information in a holistic or spatial fashion, whereas successive synthesis involves processing information sequentially with temporal links between stimuli. Analysis of the data generated in the study indicated that syllogistic reasoning and inductive reasoning were significantly correlated with both simultaneous and successive synthesis. However, the strongest correlation was found between simultaneous synthesis and inductive reasoning. These findings provide a basis for understanding the roles of spatial and verbal-logical ability as defined by Luria's neuropsychological theory in scientific problem solving. The results also highlight the need for teachers to provide experiences which are compatible with individual students' information processing styles.Received: 19 October 1993; Revised: 15 December 1994;

  1. 77 FR 64442 - Airworthiness Directives; PILATUS AIRCRAFT LTD. Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-22

    ... Maintenance Manual Temporary Revision No. 04-03, dated October 12, 2012, which transmits Unclassified 12-A/AMP..., dated October 15, 2012, which transmits Unclassified 12-B/AMP-04 Structural and Component Limitations... Revision No. 04-03, dated October 15, 2012, which transmits Unclassified 12-A/AMP-04 Structural, Component...

  2. Thermodynamics of Strecker synthesis in hydrothermal systems

    NASA Technical Reports Server (NTRS)

    Schulte, Mitchell; Shock, Everett

    1995-01-01

    Submarine hydrothermal systems on the early Earth may have been the sites from which life emerged. The potential for Strecker synthesis to produce biomolecules (amino and hydroxy acids) from starting compounds (ketones, aldehydes, HCN and ammonia) in such environments is evaluated quantitatively using thermodynamic data and parameters for the revised Helgeson-Kirkham-Flowers (HKF) equation of state. Although there is an overwhelming thermodynamic drive to form biomolecules by the Strecker synthesis at hydrothermal conditions, the availability and concentration of starting compounds limit the efficiency and productivity of Strecker reactions. Mechanisms for concentrating reactant compounds could help overcome this problem, but other mechanisms for production of biomolecules may have been required to produce the required compounds on the early Earth. Geochemical constraints imposed by hydrothermal systems provide important clues for determining the potential of these and other systems as sites for the emergence of life.

  3. Interior Design: Revision as Focus.

    ERIC Educational Resources Information Center

    Smede, Shelly D.

    2000-01-01

    Describes how the author teaches her eighth-grade students to revise their writing, providing "working revision days" in class, offering direction and structure, and thereby helping students learn how much impact going back to a piece of writing and making sweeping changes can have on the end result. (SR)

  4. The Neo Personality Inventory-Revised: Factor Structure and Gender Invariance from Exploratory Structural Equation Modeling Analyses in a High-Stakes Setting

    ERIC Educational Resources Information Center

    Furnham, Adrian; Guenole, Nigel; Levine, Stephen Z.; Chamorro-Premuzic, Tomas

    2013-01-01

    This study presents new analyses of NEO Personality Inventory-Revised (NEO-PI-R) responses collected from a large British sample in a high-stakes setting. The authors show the appropriateness of the five-factor model underpinning these responses in a variety of new ways. Using the recently developed exploratory structural equation modeling (ESEM)…

  5. Northern peatland initiation lagged abrupt increases in deglacial atmospheric CH4.

    PubMed

    Reyes, Alberto V; Cooke, Colin A

    2011-03-22

    Peatlands are a key component of the global carbon cycle. Chronologies of peatland initiation are typically based on compiled basal peat radiocarbon (14C) dates and frequency histograms of binned calibrated age ranges. However, such compilations are problematic because poor quality 14C dates are commonly included and because frequency histograms of binned age ranges introduce chronological artefacts that bias the record of peatland initiation. Using a published compilation of 274 basal 14C dates from Alaska as a case study, we show that nearly half the 14C dates are inappropriate for reconstructing peatland initiation, and that the temporal structure of peatland initiation is sensitive to sampling biases and treatment of calibrated 14C dates. We present revised chronologies of peatland initiation for Alaska and the circumpolar Arctic based on summed probability distributions of calibrated 14C dates. These revised chronologies reveal that northern peatland initiation lagged abrupt increases in atmospheric CH4 concentration at the start of the Bølling-Allerød interstadial (Termination 1A) and the end of the Younger Dryas chronozone (Termination 1B), suggesting that northern peatlands were not the primary drivers of the rapid increases in atmospheric CH4. Our results demonstrate that subtle methodological changes in the synthesis of basal 14C ages lead to substantially different interpretations of temporal trends in peatland initiation, with direct implications for the role of peatlands in the global carbon cycle.

  6. Cross-Cultural Adaptation of the Disability of Arm, Shoulder, and Hand Questionnaire: Spanish for Puerto Rico Version

    ERIC Educational Resources Information Center

    Mulero-Portela, Ana L.; Colon-Santaella, Carmen L.; Cruz-Gomez, Cynthia

    2009-01-01

    The purpose of this study was to perform a cross-cultural adaptation of the Disability of Arm, Shoulder, and Hand (DASH) questionnaire to Spanish for Puerto Rico. Five steps were followed for the cross-cultural adaptation: forward translations into Spanish for Puerto Rico, synthesis of the translations, back translations into English, revision by…

  7. Substructural controller synthesis

    NASA Technical Reports Server (NTRS)

    Su, Tzu-Jeng; Craig, Roy R., Jr.

    1989-01-01

    A decentralized design procedure which combines substructural synthesis, model reduction, decentralized controller design, subcontroller synthesis, and controller reduction is proposed for the control design of flexible structures. The structure to be controlled is decomposed into several substructures, which are modeled by component mode synthesis methods. For each substructure, a subcontroller is designed by using the linear quadratic optimal control theory. Then, a controller synthesis scheme called Substructural Controller Synthesis (SCS) is used to assemble the subcontrollers into a system controller, which is to be used to control the whole structure.

  8. Polyketides from Pestalotiopsis zonata and structure revision of pestalrones A and B.

    PubMed

    Xu, Xin; Liu, Chang; Dong, Ya-Jing; Liu, Fang-Ru; Xu, Xiu-Mei; Li, De-Sheng; Li, Dan-Yi; Li, Zhan-Lin

    2017-11-23

    The structures of pestalrones A-B were revised via reinterpretation of the NMR data and a brief chemical transformation from the co-occurring polyketides, in our investigation on the secondary metabolites of Pestalotiopsis zonata, which also afforded a new α-pyrone derivative, pestazonatic acid, and four known analogs.

  9. Preliminary Investigation of the 1991 Medical College Admission Test Factor Structure.

    ERIC Educational Resources Information Center

    Li, Weichang; Mitchell, Karen J.

    A substantially revised Medical College Admission Test (MCAT) was introduced in spring 1991. The new examination is designed to assess critical thinking skills, basic concepts and problem solving facility in science, and writing skills. This paper reports preliminary findings on the factor structure of the revised MCAT, which consists of four…

  10. The Alcohol Services Reporting System (ASRS) Revision Study.

    ERIC Educational Resources Information Center

    Borkman, Thomasina

    This document reports a revision study of the California Alcohol Services Reporting System (ASRS), a system which consists of a structure of definitions and categories of services, a budget form of planned alcohol services, instructions for the county plan, and the report of expenditures. The study problem is that the ASRS structure of…

  11. 78 FR 41436 - Proposed Revision to Treatment of Non-Safety Systems for Passive Advanced Light Water Reactors

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-10

    ... Safety Analysis Reports for Nuclear Power Plants: LWR Edition,'' on a proposed new section to its... revised position on the treatment of the high winds external hazard for certain RTNSS structures, systems... winds external hazard for certain RTNSS structures, systems and components (SSCs). This position differs...

  12. Approaches to the Chemical Synthesis of the Chlorosulfolipids

    PubMed Central

    Chung, Won-Jin; Vanderwal, Christopher D.

    2014-01-01

    CONSPECTUS Since the initial discovery of the chlorosulfolipids in 1969, the chemical synthesis community largely ignored these compounds for nearly four decades, perhaps because they contain a high density of chlorine atoms that suggested that these molecules and any projected synthetic intermediates might be unstable. Beginning in 2008, a sudden flurry of synthesis activity by several research groups, including our own, appeared in the literature. In this Account, we highlight our work from the last several years on the chemical synthesis of the chlorosulfolipids. Our work in this area began with attempts to stereoselectively generate the abundant dichloroalcohol functional group arrangements in these natural targets. In these early studies, we learned that many polychlorinated intermediates were far more stable than anticipated. We also developed a method for the diastereoselective dichlorination of allylic alcohol derivatives that permitted access to the syn,syn-dichloroalcohol stereotriad found in several chlorosulfolipids. Concurrently, we investigated an approach to mytilipin A that included multiple intermediates bearing β-chloroaldehyde functional group arrangements, but this route proved intractable. However, we leveraged what we had learned from this approach into our first success in this area: we synthesized danicalipin A via a route that introduced all of the polar functional groups using alkene oxidation reactions. By adapting this relatively general strategy, we completed an enantioselective synthesis of malhamensilipin A. This body of work also resulted in the full stereochemical elucidation of danicalipin A and the structural revision of malhamensilipin A. Finally, with the advent of Z-selective alkene cross metathesis, we developed a second-generation synthesis that featured this strategy in place of a poorly performing Wittig olefination that plagued our first approach. In addition to this new convergent step, we developed a reliable protocol for diastereoselective addition to highly sensitive α,β-dichloroaldehydes and a method for kinetic resolution of complex vinyl epoxides. Altogether, these advances led to a synthesis of enantioenriched mytilipin A in only eight steps. In the context of this work, we discovered a number of highly stereoselective reactions that might offer new, broadly applicable lessons in acyclic stereocontrol. Moreover, this research testifies to the stability of polychlorinated molecules and should inspire confidence in the use of aliphatic chlorides in other applications, including in discovery chemistry. PMID:24400674

  13. Factor Structure of the Revised TOEIC[R] Test: A Multiple-Sample Analysis

    ERIC Educational Resources Information Center

    In'nami, Yo; Koizumi, Rie

    2012-01-01

    This study examined the factor structure of the listening and reading sections of the revised Test of English for International Communication (TOEIC[R]) test. The data from the TOEIC IP (institutional program) test taken by 569 English learners were randomly split into two samples (n = 285 vs. 284). Four models (higher-order, correlated,…

  14. Validating the Repetitive Behavior Scale-Revised in Young Children with Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Mirenda, Pat; Smith, Isabel M.; Vaillancourt, Tracy; Georgiades, Stelios; Duku, Eric; Szatmari, Peter; Bryson, Susan; Fombonne, Eric; Roberts, Wendy; Volden, Joanne; Waddell, Charlotte; Zwaigenbaum, Lonnie

    2010-01-01

    This study examined the factor structure of the Repetitive Behavior Scale-Revised (RBS-R) in a sample of 287 preschool-aged children with autism spectrum disorder (ASD). A confirmatory factor analysis was used to examine six competing structural models. Spearman's rank order correlations were calculated to examine the associations between factor…

  15. 75 FR 34714 - Updated Record of Decision (ROD) for Revised Army Growth and Force; Structure Realignment Decisions

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-18

    ...-making process for decisions contained in the updated ROD (2010). The conversion of an HBCT to an SBCT at... DEPARTMENT OF DEFENSE Department of the Army Updated Record of Decision (ROD) for Revised Army Growth and Force; Structure Realignment Decisions AGENCY: Department of the Army, DoD. ACTION: Notice of...

  16. Interval Estimation of Revision Effect on Scale Reliability via Covariance Structure Modeling

    ERIC Educational Resources Information Center

    Raykov, Tenko

    2009-01-01

    A didactic discussion of a procedure for interval estimation of change in scale reliability due to revision is provided, which is developed within the framework of covariance structure modeling. The method yields ranges of plausible values for the population gain or loss in reliability of unidimensional composites, which results from deletion or…

  17. Eyelid transplantation: lessons from a total face transplant and the importance of blink.

    PubMed

    Sosin, Michael; Mundinger, Gerhard S; Dorafshar, Amir H; Fisher, Mark; Bojovic, Branko; Christy, Michael R; Iliff, Nicholas T; Rodriguez, Eduardo D

    2015-01-01

    Despite inclusion of periorbital structures in facial transplants, critical assessment of posttransplantation short- and long-term periorbital function has not been reported. The purpose of this article is to report recovery of ocular and periorbital function, with critical appraisal of posttransplant blink in the setting of revision surgery. Prospective ocular and periorbital functional assessments were completed at multiple time points in a patient undergoing facial transplantation and subsequent revision operations. Function was evaluated using clinical ocular examinations, visual acuity assessments, photography, and video at various intervals from preoperative baseline to 13.5 months after transplantation. During this period, revision operations involving periorbital structures were performed at 6 and 9 months after transplantation. Before transplantation, volitional blink was 100 percent in both eyes. Involuntary blink was 40 percent in the right eye and 90 percent in the left eye, with occasional full closure. Following face transplantation, voluntary blink was preserved, partial skin sensation was present, and involuntary blink improved to 70 percent in the right eye and 100 percent in the left eye. Following revision surgery, visual acuity and voluntary and involuntary blink were impaired. By 7.5 months after revision, improvement comparable to the pretransplantation assessment was observed. Adherence to principles of blink preservation is critical in periorbital transplantation. Involuntary blink is essential for preserving vision, and can be improved after transplantation. Revision surgery may temporarily impair advances made with initial allotransplantation. A comprehensive understanding of ocular biomechanics and function is invaluable to the reconstructive surgeon performing facial transplantation involving periorbital structures and posttransplant revision operations. Therapeutic, V.

  18. Working Memory and the Revision of Syntactic and Discourse Ambiguities

    PubMed Central

    Evans, William S.; Caplan, David; Ostrowski, Adam; Michaud, Jennifer; Guarino, Anthony; Waters, Gloria

    2015-01-01

    Two hundred participants, 50 in each of four age ranges (19 – 29; 30 – 49, 50 – 69, 70 – 90) were tested for short term working memory, speed of processing and on-line processing of three types of sentences in which an initially assigned syntactic structure and/or semantic interpretation had to be revised. Self-paced reading times were longer for the segments which signaled the need for revision, and there were interactions of age and sentence type and of speed of processing and sentence type, but not of working memory and sentence type, on reading times for these segments. The results provide evidence that working memory does not support the processes that revise the structure and interpretation of sentences and discourse. PMID:25485458

  19. Results of a Cognitive Interview Study of Immediate Feedback and Revision Opportunities for Students with Disabilities in Large Scale Assessments. Synthesis Report 92

    ERIC Educational Resources Information Center

    Johnstone, Christopher; Figueroa, Chantal; Attali, Yigal; Stone, Elizabeth; Laitusis, Cara

    2013-01-01

    Validly assessing students with disabilities has been a challenge for decades but is increasingly vital to educational policy and practice in the current era of accountability. Numerous technological and policy developments have occurred in the past several years with the emergence and decline of various forms of alternate assessments. This study…

  20. Integrated Science Assessment (ISA) for Oxides of Nitrogen, Oxides of Sulfur and Particulate Matter - Ecological Criteria (First External Review Draft, Mar 2017)

    EPA Science Inventory

    This draft ISA document represents a concise synthesis and evaluation of the most policy-relevant science and will ultimately provide the scientific bases for EPA’s decision on retaining or revising the current secondary standards for NO2, SO2, PM 2.5 and PM 10 since the prior re...

  1. Flexible synthesis of poison-frog alkaloids of the 5,8-disubstituted indolizidine-class. II: Synthesis of (-)-209B, (-)-231C, (-)-233D, (-)-235B", (-)-221I, and an epimer of 193E and pharmacological effects at neuronal nicotinic acetylcholine receptors.

    PubMed

    Kobayashi, Soushi; Toyooka, Naoki; Zhou, Dejun; Tsuneki, Hiroshi; Wada, Tsutomu; Sasaoka, Toshiyasu; Sakai, Hideki; Nemoto, Hideo; Garraffo, H Martin; Spande, Thomas F; Daly, John W

    2007-01-01

    The 5,8-disubstituted indolizidines constitute the largest class of poison-frog alkaloids. Some alkaloids have been shown to act as noncompetitive blockers at nicotinic acetylcholine receptors but the proposed structures and the biological activities of most of the 5,8-disubstituted indolizidines have not been determined because of limited supplies of the natural products. We have therefore conducted experiments to confirm proposed structures and determine biological activities using synthetic compounds. Recently, we reported that one of this class of alkaloids, (-)-235B', acts as a noncompetitive antagonist for α4β2 nicotinic receptors, and its sensitivity is comparable to that of the classical competitive antagonist for this receptor, dihydro-β-erythroidine. The enantioselective syntheses of (-)-209B, (-)-231C, (-)-233D, (-)-235B", (-)-221I, and what proved to be an epimer of natural 193E, starting from common chiral lactams have been achieved. When we performed electrophysiological recordings to examine the effects of the synthetic alkaloids on two major subtypes of nicotinic receptors (α4β2 and α7) expressed in Xenopus laevis oocytes, (-)-231C effectively blocked α4β2 receptor responses (IC(50 )value, 1.5 μM) with a 7.0-fold higher potency than for blockade of α7 receptor responses. In contrast, synthetic (-)-221I and (-)-epi-193E were more potent in blocking α7 receptor responses (IC(50 )value, 4.4 μM and 9.1 μM, respectively) than α4β2 receptor responses (5.3-fold and 2.0-fold, respectively). We achieved the total synthesis of (-)-209B, (-)-231C, (-)-233D, (-)-235B", (-)-221I, and an epimer of 193E starting from common chiral lactams, and the absolute stereochemistry of natural (-)-233D was determined. Furthermore, the relative stereochemistry of (-)-231C and (-)-221I was also determined. The present asymmetric synthesis of the proposed structure for 193E revealed that the C-8 configuration of natural 193E should be revised. The selectivity for α4β2 and α7 nicotinic receptors differed markedly for the 5,8-disubstituted indolizidines tested, and thus it appears that the nature of the side chains in these indolizidines is crucial with regard to subtype-selectivity.

  2. Improved Diagnostic Validity of the ADOS Revised Algorithms: A Replication Study in an Independent Sample

    ERIC Educational Resources Information Center

    Oosterling, Iris; Roos, Sascha; de Bildt, Annelies; Rommelse, Nanda; de Jonge, Maretha; Visser, Janne; Lappenschaar, Martijn; Swinkels, Sophie; van der Gaag, Rutger Jan; Buitelaar, Jan

    2010-01-01

    Recently, Gotham et al. ("2007") proposed revised algorithms for the Autism Diagnostic Observation Schedule (ADOS) with improved diagnostic validity. The aim of the current study was to replicate predictive validity, factor structure, and correlations with age and verbal and nonverbal IQ of the ADOS revised algorithms for Modules 1 and 2…

  3. Revision of the Structures of 1,5-Dihydroxy-3,8-epoxyvalechlorine, Volvaltrate B, and Valeriotetrate C from Valeriana jatamansi and V. officinalis.

    PubMed

    Lin, Sheng; Shen, Yun-Heng; Zhang, Zhong-Xiao; Li, Hui-Liang; Shan, Lei; Liu, Run-Hui; Xu, Xi-Ke; Zhang, Wei-Dong

    2010-10-22

    The structures of 1,5-dihydroxy-3,8-epoxyvalechlorine (1a) and volvaltrate B (6a), two new chlorinated iridoids isolated from Valeriana jatamansi and V. officinalis, respectively, were originally assigned on the basis of spectroscopic methods. Reinvestigation using X-ray analysis and chemical transformation revealed that the original assignment of H-7 in 1a and OH-8 in 6a should be inverted and that the structures should be revised to 1 and 6, respectively. Correspondingly, the structure of valeriotetrate C (7a) should be revised to 7. Volvaltrate B (6) showed cytotoxic activity against the lung adenocarcinoma (A549), metastatic prostate cancer (PC-3M), colon cancer (HCT-8), and hepatoma (Bel7402) cell lines, with IC50 values of 8.5, 2.0, 3.2, and 6.1 μM, respectively.

  4. Structural, Item, and Test Generalizability of the Psychopathy Checklist-Revised to Offenders with Intellectual Disabilities

    ERIC Educational Resources Information Center

    Morrissey, Catrin; Cooke, David; Michie, Christine; Hollin, Clive; Hogue, Todd; Lindsay, William R.; Taylor, John L.

    2010-01-01

    The Psychopathy Checklist-Revised (PCL-R) is the most widely used measure of psychopathy in forensic clinical practice, but the generalizability of the measure to offenders with intellectual disabilities (ID) has not been clearly established. This study examined the structural equivalence and scalar equivalence of the PCL-R in a sample of 185 male…

  5. Structure A, architectural sections & details. Drawing no. H2, revised ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Structure A, architectural sections & details. Drawing no. H2, revised as-built dated October 11, 1951. Original drawing by Black & Veatch, consulting engineers, Kansas City, Missouri, prepared for the U.S. Department of the Army, Office of Engineers, Military Construction Division, Washington, D.C. dated October 1. - Travis Air Force Base, Building No. 925, W Street, Fairfield, Solano County, CA

  6. The Structural and Predictive Properties of the Psychopathy Checklist-Revised in Canadian Aboriginal and Non-Aboriginal Offenders

    ERIC Educational Resources Information Center

    Olver, Mark E.; Neumann, Craig S.; Wong, Stephen C. P.; Hare, Robert D.

    2013-01-01

    We examined the structural and predictive properties of the Psychopathy Checklist-Revised (PCL-R) in large samples of Canadian male Aboriginal and non-Aboriginal offenders. The PCL-R ratings were part of a risk assessment for criminal recidivism, with a mean follow-up of 26 months postrelease. Using multigroup confirmatory factor analysis, we were…

  7. Factor Structure of Scores from the Conners' Rating Scales-Revised among Nepali Children

    ERIC Educational Resources Information Center

    Pendergast, Laura L.; Vandiver, Beverly J.; Schaefer, Barbara A.; Cole, Pamela M.; Murray-Kolb, Laura E.; Christian, Parul

    2014-01-01

    This study used exploratory and confirmatory factor analyses to examine the structures of scores from the Conners' Teacher and Parent Rating Scales-Revised (CTRS-R and CPRS-R, respectively; Conners, 1997). The scales were administered to 1,835 parents and 1,387 teachers of children in Nepal's Sarlahi district, a region where no other measures of…

  8. Validating the Revised Illness Perception Questionnaire as a Measure of Parent Perceptions of Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Mire, Sarah S.; Tolar, Tammy D.; Brewton, Christie M.; Raff, Natalie S.; McKee, Shannon L.

    2018-01-01

    The illness perception questionnaire (IPQ) and its revision (IPQ-R) measure perceptions about health-related diagnoses and the influence of cognitions on coping. In this study, the factor structure of a version revised for use with autism spectrum disorder (ASD) was investigated with a sample of parents (n = 361) whose children have ASD.…

  9. Interface-Assisted Synthesis of 2D Materials: Trend and Challenges.

    PubMed

    Dong, Renhao; Zhang, Tao; Feng, Xinliang

    2018-06-18

    The discovery of graphene one decade ago has triggered enormous interest in developing two-dimensional materials (2DMs)-that is 2D allotropes of various elements or compounds (consisting of two or more covalently bonded elements) or molecular frameworks with periodic structures. At present, various synthesis strategies have been exploited to produce 2DMs, such as top-down exfoliation and bottom-up chemical vapor deposition and solution synthesis methods. In this review article, we will highlight the interfacial roles toward the controlled synthesis of inorganic and organic 2DMs with varied structural features. We will summarize the state-of-the-art progress on interfacial synthesis strategies and address their advancements in the structural, morphological, and crystalline control by the direction of the arrangement of the molecules or precursors at a confined 2D space. First, we will provide an overview of the interfaces and introduce their advantages and uniqueness for the synthesis of 2DMs, followed by a brief classification of inorganic and organic 2DMs achieved by interfacial synthesis. Next, the currently developed interfacial synthesis strategies combined with representative inorganic and organic 2DMs are summarized, including the description of method details, the corresponding structural features, and the insights into the advantages and limitations of the synthesis methods, along with some recommendable characterization methods for understanding the interfacial assembly of the precursors and crystal growth of 2DMs. After that, we will discuss several classes of emerging organic 2DMs with particular emphasis on the structural control by the interfacial synthesis strategies. Note that, inorganic 2DMs will not be categorized separately due to the fact that a number of review articles have covered the synthesis, structure, processing, and applications. Finally, the challenges and perspectives are provided regarding the future development of interface-assisted synthesis of 2DMs with diverse structural and functional control.

  10. SSME/side loads analysis for flight configuration, revision A. [structural analysis of space shuttle main engine under side load excitation

    NASA Technical Reports Server (NTRS)

    Holland, W.

    1974-01-01

    This document describes the dynamic loads analysis accomplished for the Space Shuttle Main Engine (SSME) considering the side load excitation associated with transient flow separation on the engine bell during ground ignition. The results contained herein pertain only to the flight configuration. A Monte Carlo procedure was employed to select the input variables describing the side load excitation and the loads were statistically combined. This revision includes an active thrust vector control system representation and updated orbiter thrust structure stiffness characteristics. No future revisions are planned but may be necessary as system definition and input parameters change.

  11. Cross-Cultural Adaptation, Reliability and Validity of the Danish Version of the Readiness for Return to Work Instrument.

    PubMed

    Stapelfeldt, Christina Malmose; Momsen, Anne-Mette Hedeager; Lund, Thomas; Grønborg, Therese Koops; Hogg-Johnson, Sheilah; Jensen, Chris; Skakon, Janne; Labriola, Merete

    2018-06-06

    The objective of the present study was to translate and validate the Canadian Readiness for Return To Work instrument (RRTW-CA) into a Danish version (RRTWDK) by testing its test-retest and internal consistency reliability and its structural and construct validity. Cross-cultural adaptation of the six-staged RRTW-CA instrument was performed in a standardised, systematic five-step-procedure; forward translation, panel synthesis of the translation, back translation, consolidation and revision by researchers, and finally pre-testing. This RRTW-DK beta-version was tested for its psychometric properties by intra-class correlation coefficient and standard error of measurement (n = 114), Cronbach's alpha (n = 471), confirmatory factor analyses (n = 373), and Spearman's rank correlation coefficient (n = 436) in sickness beneficiaries from a municipal employment agency and hospital wards. The original RRTW-CA stage structure could not be confirmed in the RRTWDK. The psychometric properties were thus inconclusive. The RRTW-DK cannot be recommended for use in the current version as the RRTW construct is questionable. The RRTW construct needs further exploration, preferably in a population that is homogeneous with regard to cause of sickness, disability duration and age.

  12. Synthesis, NMR conformational analysis and pharmacological evaluation of 7,7a,13,14-tetrahydro-6H-cyclobuta[b]pyrimido[1,2-a:3,4-a']diindole analogues as melatonin receptor ligands.

    PubMed

    Attia, Mohamed I; Güclü, Deniz; Hertlein, Barbara; Julius, Justin; Witt-Enderby, Paula A; Zlotos, Darius P

    2007-07-07

    A structure for the self-condensation product of 2-(1H-indol-2-yl)ethyl tosylate 2a, previously proposed as 6,7,14,15-tetrahydro-15aH-azocino[1,2-a:6,5-b]diindole 3a, was revised based on the (13)C-2D-INADEQUATE experiment, and proved to be 7,7a,13,14-tetrahydro-6H-cyclobuta[b]pyrimido[1,2-a:3,4-a']diindole 4a. A mechanism for the unexpected formation of this novel hexacyclic heterocycle was proposed and its NMR solution structure was elucidated. Five derivatives of the title ring skeleton 12-16 designed as melatonin receptor ligands were synthesized and their affinities for the human MT(1) and MT(2) receptors were determined. Both butyramides 13 and 15, as well as the non-methoxy acetamide 12 exhibited micromolar binding affinities for both receptors being slightly MT(2) selective. The methoxy acetamide 14 showed the best pharmacological profile exhibiting a five times higher affinity for MT(1) (K(i) = 49 nM) than for MT(2) (K(i) = 246 nM) receptor.

  13. Does a cemented cage improve revision THA for severe acetabular defects?

    PubMed

    Hansen, Erik; Shearer, David; Ries, Michael D

    2011-02-01

    Evidence suggests a growing incidence of revision total hip arthroplasty (THA) including a subset with large acetabular defects. Revision THA for severe acetabular bone loss is associated with a relatively high rate of mechanical failure. We questioned whether cementing a cage to the reconstructed acetabular defect and pelvis would improve the rate of mechanical failure for patients with Type 3 defects (Paprosky et al.) with and without pelvic discontinuity in comparison to historical controls. We retrospectively collected data on 33 patients who underwent 35 revision THAs using an acetabular reconstruction cage cemented to morselized allograft and either structural allograft or trabecular metal augmentation for Type 3 defects in the presence (n = 13) and absence (n = 22) of pelvic discontinuity at a mean followup of 59 months (range, 24-92 months). The primary outcome was mechanical failure, defined as revision of the acetabular reconstruction for aseptic loosening. Revision surgery for mechanical failure occurred in four of the 13 patients with pelvic discontinuity and two of the 22 patients without discontinuity. Radiographic loosening occurred in one patient with and one patient without pelvic discontinuity. Seven of the 35 revisions were subsequently revised for deep infection all in patients who were immunocompromised. Cementing the cage to the pelvis can offer an advantage for treating severe acetabular defects. Trabecular metal augmentation appears to provide better initial mechanical stability than a structural allograft, but successful allograft reconstruction may restore bone stock. Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

  14. The Effects of Repeated Writing and Repeated Revision Strategies on Composing Fluency of Learning Disabled Adolescents. Final Report.

    ERIC Educational Resources Information Center

    Harriman, Nancy E.; Gajar, Anna H.

    The study investigated the use of repeated writings as a means of increasing written language fluency with 48 learning disabled students in senior high school resource room English classes. Subjects received one of four treatments for 4 days: repeated writing with structural cues, repeated revision with structural cues, writing on a new topic with…

  15. Structure A, protective alarm installation details. Drawing no. H3709, revised ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Structure A, protective alarm installation details. Drawing no. H3-709, revised as-built dated August 28, 1952. Original drawing by Black & Veatch, consulting engineers, Kansas City, Missouri, prepared for the U.S. Department of the Army, Office of Engineers, Military Construction Division, Washington, D.C. dated October 1, 1951. - Travis Air Force Base, Building No. 925, W Street, Fairfield, Solano County, CA

  16. The Anxiety Sensitivity Index--Revised: Confirmatory Factor Analyses, Structural Invariance in Caucasian and African American Samples, and Score Reliability and Validity

    ERIC Educational Resources Information Center

    Arnau, Randolph C.; Broman-Fulks, Joshua J.; Green, Bradley A.; Berman, Mitchell E.

    2009-01-01

    The most commonly used measure of anxiety sensitivity is the 36-item Anxiety Sensitivity Index--Revised (ASI-R). Exploratory factor analyses have produced several different factors structures for the ASI-R, but an acceptable fit using confirmatory factor analytic approaches has only been found for a 21-item version of the instrument. We evaluated…

  17. Northern peatland initiation lagged abrupt increases in deglacial atmospheric CH4

    PubMed Central

    Reyes, Alberto V.; Cooke, Colin A.

    2011-01-01

    Peatlands are a key component of the global carbon cycle. Chronologies of peatland initiation are typically based on compiled basal peat radiocarbon (14C) dates and frequency histograms of binned calibrated age ranges. However, such compilations are problematic because poor quality 14C dates are commonly included and because frequency histograms of binned age ranges introduce chronological artefacts that bias the record of peatland initiation. Using a published compilation of 274 basal 14C dates from Alaska as a case study, we show that nearly half the 14C dates are inappropriate for reconstructing peatland initiation, and that the temporal structure of peatland initiation is sensitive to sampling biases and treatment of calibrated 14C dates. We present revised chronologies of peatland initiation for Alaska and the circumpolar Arctic based on summed probability distributions of calibrated 14C dates. These revised chronologies reveal that northern peatland initiation lagged abrupt increases in atmospheric CH4 concentration at the start of the Bølling–Allerød interstadial (Termination 1A) and the end of the Younger Dryas chronozone (Termination 1B), suggesting that northern peatlands were not the primary drivers of the rapid increases in atmospheric CH4. Our results demonstrate that subtle methodological changes in the synthesis of basal 14C ages lead to substantially different interpretations of temporal trends in peatland initiation, with direct implications for the role of peatlands in the global carbon cycle. PMID:21368146

  18. New multirate sampled-data control law structure and synthesis algorithm

    NASA Technical Reports Server (NTRS)

    Berg, Martin C.; Mason, Gregory S.; Yang, Gen-Sheng

    1992-01-01

    A new multirate sampled-data control law structure is defined and a new parameter-optimization-based synthesis algorithm for that structure is introduced. The synthesis algorithm can be applied to multirate, multiple-input/multiple-output, sampled-data control laws having a prescribed dynamic order and structure, and a priori specified sampling/update rates for all sensors, processor states, and control inputs. The synthesis algorithm is applied to design two-input, two-output tip position controllers of various dynamic orders for a sixth-order, two-link robot arm model.

  19. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Goltz, G.; Weiner, H.

    A computer program has been developed for designing and analyzing the performance of solar array/battery power systems for the U.S. Coast Guard Navigational Aids. This program is called the Design Synthesis/Performance Analysis (DSPA) Computer Program. The basic function of the Design Synthesis portion of the DSPA program is to evaluate functional and economic criteria to provide specifications for viable solar array/battery power systems. The basic function of the Performance Analysis portion of the DSPA program is to simulate the operation of solar array/battery power systems under specific loads and environmental conditions. This document provides a detailed description of the DSPAmore » Computer Program system and its subprograms. This manual will assist the programmer in revising or updating the several subprograms.« less

  20. Seeing Our Way Clear: Feminist Revision of the Academy. Proceedings of the Annual GLCA Women's Studies Conference (8th, November 5-7, 1981).

    ERIC Educational Resources Information Center

    Loring, Katherine, Ed.; And Others

    Two keynote addresses and 12 selected papers are included in these conference proceedings. The keynote address, "Seeing Our Way Clear: Feminist Re-Vision of the Academy" (Peggy McIntosh), describes the academy as a "hierarchical or layered pyramidal structure" and discusses the benefits of feminist revision. The first of 12…

  1. Rotational and Infrared Spectroscopy of Ethanimine: A Route toward Its Astrophysical and Planetary Detection

    NASA Astrophysics Data System (ADS)

    Melli, Alessio; Melosso, Mattia; Tasinato, Nicola; Bosi, Giulio; Spada, Lorenzo; Bloino, Julien; Mendolicchio, Marco; Dore, Luca; Barone, Vincenzo; Puzzarini, Cristina

    2018-03-01

    Ethanimine, a possible precursor of amino acids, is considered an important prebiotic molecule and thus may play important roles in the formation of biological building blocks in the interstellar medium. In addition, its identification in Titan’s atmosphere would be important for understanding the abiotic synthesis of organic species. An accurate computational characterization of the molecular structure, energetics, and spectroscopic properties of the E and Z isomers of ethanimine, CH3CHNH, has been carried out by means of a composite scheme based on coupled-cluster techniques, which also account for extrapolation to the complete basis-set limit and core-valence correlation correction, combined with density functional theory for the treatment of vibrational anharmonic effects. By combining the computational results with new millimeter-wave measurements up to 300 GHz, the rotational spectrum of both isomers can be accurately predicted up to 500 GHz. Furthermore, our computations allowed us to revise the infrared spectrum of both E- and Z-CH3CHNH, thus predicting all fundamental bands with high accuracy.

  2. TED analysis of the Si(113) surface structure

    NASA Astrophysics Data System (ADS)

    Suzuki, T.; Minoda, H.; Tanishiro, Y.; Yagi, K.

    1999-09-01

    We carried out a TED (transmission electron diffraction) analysis of the Si(113) surface structure. The TED patterns taken at room temperature showed reflections due to the 3×2 reconstructed structure. The TED pattern indicated that a glide plane parallel to the <332> direction suggested in some models is excluded. We calculated the R-factors (reliability factors) for six surface structure models proposed previously. All structure models with energy-optimized atomic positions have large R-factors. After revision of the atomic positions, the R-factors of all the structure models decreased below 0.3, and the revised version of Dabrowski's 3×2 model has the smallest R-factor of 0.17.

  3. Protocol: realist synthesis of the impact of unemployment insurance policies on poverty and health.

    PubMed

    Molnar, Agnes; O'Campo, Patricia; Ng, Edwin; Mitchell, Christiane; Muntaner, Carles; Renahy, Emilie; St John, Alexander; Shankardass, Ketan

    2015-02-01

    Unemployment insurance is an important social protection policy that buffers unemployed workers against poverty and poor health. Most unemployment insurance studies focus on whether increases in unemployment insurance generosity are predictive of poverty and health outcomes. Less work has used theory-driven approaches to understand and explain how and why unemployment insurance works, for whom, and under what circumstances. Given this, we present a realist synthesis protocol that seeks to unpack how contextual influences trigger relevant mechanisms to generate poverty and health outcomes. In this protocol, we conceptualize unemployment insurance as a key social protection policy; provide a supporting rationale on the need for a realist synthesis; and describe our process on identifying context-mechanism-outcome pattern configurations. Six methodological steps are described: initial theory development, search strategy; selection and appraisal of documents; data extraction; analysis and synthesis process; and presentation and dissemination of revised theory. Our forthcoming realist synthesis will be the first to build and test theory on the intended and unintended outcomes of unemployment insurance policies. Anticipated findings will allow policymakers to move beyond 'black box' approaches to consider 'mechanism-based' explanations that explicate the logic on how and why unemployment insurance matters. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Revised U.S. Climate Science Plan Still Lacking in Key Areas

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2004-03-01

    A U.S. National Research Council committee has found that a revised strategic plan for the U.S. Climate Change Science Program (CCSP) includes elements ``that could permit it to effectively guide research on climate and associated global changes over the next decades.'' However, the committee noted that the revision, issued by the CCSP, faces major hurdles related to funding, program priorities, management structure, and maintaining political independence.

  5. Revised description of the fine structure of in situ "zooxanthellae" genus Symbiodinium.

    PubMed

    Wakefield, T S; Farmer, M A; Kempf, S C

    2000-08-01

    The fine structure of the symbiotic dinoflagellate genus Symbiodinium has been well described. All of the published descriptions are based on tissue that was fixed in standard aldehyde and osmium fixatives and dehydrated in an ethanol series before embedding. When the technique of freeze-substitution was used to fix tissue from Cassiopeia xamachana, Aiptasia pallida, and Phyllactis flosculifera and prepare it for embedding, thecal vesicles were revealed within the in situ symbionts of all three species. Although these structures have been identified in cultured symbionts, they have never been described in the in situ symbionts. A review of the literature has revealed several instances where thecal vesicles were either overlooked or identified incorrectly. Thus the formal description of the genus Symbiodinium, which describes the in situ symbionts, contains information that is based on artifact and should be revised. A revision of the genus is suggested, and the true nature of these structures and their significance in the symbiotic association are discussed.

  6. 'Great is Darwin and Bergson his poet': Julian Huxley's other evolutionary synthesis.

    PubMed

    Herring, Emily

    2018-01-01

    In 1912, Julian Huxley published his first book The Individual in the Animal Kingdom which he dedicated to the then world-famous French philosopher Henri Bergson. Historians have generally adopted one of two attitudes towards Huxley's early encounter with Bergson. They either dismiss it entirely as unimportant or minimize it, deeming it a youthful indiscretion preceding Huxley's full conversion to Fisherian Darwinism. Close biographical study and archive materials demonstrate, however, that neither position is tenable. The study of the Bergsonian elements in play in Julian Huxley's early works fed into Huxley's first ideas about progress in evolution and even his celebrated theories of bird courtship. Furthermore, the view that Huxley rejected Bergson in his later years needs to be revised. Although Huxley ended up claiming that Bergson's theory of evolution had no explanatory power, he never repudiated the descriptive power of Bergson's controversial notion of the élan vital. Even into the Modern Synthesis period, Huxley represented his own synthesis as drawing decisively on Bergson's philosophy.

  7. A Program Structure for Event-Based Speech Synthesis by Rules within a Flexible Segmental Framework.

    ERIC Educational Resources Information Center

    Hill, David R.

    1978-01-01

    A program structure based on recently developed techniques for operating system simulation has the required flexibility for use as a speech synthesis algorithm research framework. This program makes synthesis possible with less rigid time and frequency-component structure than simpler schemes. It also meets real-time operation and memory-size…

  8. Bio-mimicking nano and micro-structured surface fabrication for antibacterial properties in medical implants.

    PubMed

    Jaggessar, Alka; Shahali, Hesam; Mathew, Asha; Yarlagadda, Prasad K D V

    2017-10-02

    Orthopaedic and dental implants have become a staple of the medical industry and with an ageing population and growing culture for active lifestyles, this trend is forecast to continue. In accordance with the increased demand for implants, failure rates, particularly those caused by bacterial infection, need to be reduced. The past two decades have led to developments in antibiotics and antibacterial coatings to reduce revision surgery and death rates caused by infection. The limited effectiveness of these approaches has spurred research into nano-textured surfaces, designed to mimic the bactericidal properties of some animal, plant and insect species, and their topographical features. This review discusses the surface structures of cicada, dragonfly and butterfly wings, shark skin, gecko feet, taro and lotus leaves, emphasising the relationship between nano-structures and high surface contact angles on self-cleaning and bactericidal properties. Comparison of these surfaces shows large variations in structure dimension and configuration, indicating that there is no one particular surface structure that exhibits bactericidal behaviour against all types of microorganisms. Recent bio-mimicking fabrication methods are explored, finding hydrothermal synthesis to be the most commonly used technique, due to its environmentally friendly nature and relative simplicity compared to other methods. In addition, current proposed bactericidal mechanisms between bacteria cells and nano-textured surfaces are presented and discussed. These models could be improved by including additional parameters such as biological cell membrane properties, adhesion forces, bacteria dynamics and nano-structure mechanical properties. This paper lastly reviews the mechanical stability and cytotoxicity of micro and nano-structures and materials. While the future of nano-biomaterials is promising, long-term effects of micro and nano-structures in the body must be established before nano-textures can be used on orthopaedic implant surfaces as way of inhibiting bacterial adhesion.

  9. A Measurement Invariance Examination of the Revised Child Anxiety and Depression Scale in a Southern Sample: Differential Item Functioning between African American and Caucasian Youth

    ERIC Educational Resources Information Center

    Trent, Lindsay Rae; Buchanan, Erin; Ebesutani, Chad; Ale, Chelsea M.; Heiden, Laurie; Hight, Terry L.; Damon, John D.; Young, John

    2013-01-01

    This study examined the psychometric properties of the Revised Child Anxiety and Depression Scale in a large sample of youth from the Southern United States. The authors aimed to determine (a) if the established six-factor Revised Child Anxiety and Depression Scale structure could be replicated in this Southern sample and (b) if scores were…

  10. Heterocyclic Salt Synthesis and Rational Properties Tailoring (PREPRINT)

    DTIC Science & Technology

    2009-06-23

    performance behavior can be tailored in a controlled manner, defines the objective of a pertinent synthesis effort. Achieving this objective by...the structure of the anion. To illustrate this premise, four general synthesis methods to synthesize heterocyclic salts, including several new binary...manner, defines the objective of a pertinent synthesis effort. Achieving this objective by introducing structural alterations in a neutral covalent

  11. High-Throughput Synthesis and Structure of Zeolite ZSM-43 with Two-Directional 8-Ring Channels.

    PubMed

    Willhammar, Tom; Su, Jie; Yun, Yifeng; Zou, Xiaodong; Afeworki, Mobae; Weston, Simon C; Vroman, Hilda B; Lonergan, William W; Strohmaier, Karl G

    2017-08-07

    The aluminosilicate zeolite ZSM-43 (where ZSM = Zeolite Socony Mobil) was first synthesized more than 3 decades ago, but its chemical structure remained unsolved because of its poor crystallinity and small crystal size. Here we present optimization of the ZSM-43 synthesis using a high-throughput approach and subsequent structure determination by the combination of electron crystallographic methods and powder X-ray diffraction. The synthesis required the use of a combination of both inorganic (Cs + and K + ) and organic (choline) structure-directing agents. High-throughput synthesis enabled a screening of the synthesis conditions, which made it possible to optimize the synthesis, despite its complexity, in order to obtain a material with significantly improved crystallinity. When both rotation electron diffraction and high-resolution transmission electron microscopy imaging techniques are applied, the structure of ZSM-43 could be determined. The structure of ZSM-43 is a new zeolite framework type and possesses a unique two-dimensional channel system limited by 8-ring channels. ZSM-43 is stable upon calcination, and sorption measurements show that the material is suitable for adsorption of carbon dioxide as well as methane.

  12. Student-initiated revision in child health.

    PubMed

    Alfaham, M; Gray, O P; Davies, D P

    1994-03-01

    Most teaching of child health in Cardiff takes place in block attachments of 8 weeks. There is an introductory seminar of 2 days followed by a 6-week clinical attachment in a district general hospital in Wales, and then a revision period of one week designed to help students formalize and structure their basic knowledge and to clarify aspects of child health which they may have had difficulty in understanding. The revision programme has to take into account: the short time available, the small number of teaching staff, the most relevant basic knowledge and active participation by the student. This paper describes how this week has been improved through the use of student-initiated revision (SIR). The students' appraisal of this revision and in particular SIR is presented.

  13. Synthesis of Chemiluminescent Esters: A Combinatorial Synthesis Experiment for Organic Chemistry Students

    ERIC Educational Resources Information Center

    Duarte, Robert; Nielson, Janne T.; Dragojlovic, Veljko

    2004-01-01

    A group of techniques aimed at synthesizing a large number of structurally diverse compounds is called combinatorial synthesis. Synthesis of chemiluminescence esters using parallel combinatorial synthesis and mix-and-split combinatorial synthesis is experimented.

  14. A Second-Order Confirmatory Factor Analysis of the Moral Distress Scale-Revised for Nurses.

    PubMed

    Sharif Nia, Hamid; Shafipour, Vida; Allen, Kelly-Ann; Heidari, Mohammad Reza; Yazdani-Charati, Jamshid; Zareiyan, Armin

    2017-01-01

    Moral distress is a growing problem for healthcare professionals that may lead to dissatisfaction, resignation, or occupational burnout if left unattended, and nurses experience different levels of this phenomenon. This study aims to investigate the factor structure of the Persian version of the Moral Distress Scale-Revised in intensive care and general nurses. This methodological research was conducted with 771 nurses from eight hospitals in the Mazandaran Province of Iran in 2017. Participants completed the Moral Distress Scale-Revised, data collected, and factor structure assessed using the construct, convergent, and divergent validity methods. The reliability of the scale was assessed using internal consistency (Cronbach's alpha, Theta, and McDonald's omega coefficients) and construct reliability. Ethical considerations: This study was approved by the Ethics Committee of Mazandaran University of Medical Sciences. The exploratory factor analysis ( N = 380) showed that the Moral Distress Scale-Revised has five factors: lack of professional competence at work, ignoring ethical issues and patient conditions, futile care, carrying out the physician's orders without question and unsafe care, and providing care under personal and organizational pressures, which explained 56.62% of the overall variance. The confirmatory factor analysis ( N = 391) supported the five-factor solution and the second-order latent factor model. The first-order model did not show a favorable convergent and divergent validity. Ultimately, the Moral Distress Scale-Revised was found to have a favorable internal consistency and construct reliability. The Moral Distress Scale-Revised was found to be a multidimensional construct. The data obtained confirmed the hypothesis of the factor structure model with a latent second-order variable. Since the convergent and divergent validity of the scale were not confirmed in this study, further assessment is necessary in future studies.

  15. Computer supported collaborative learning in a clerkship: an exploratory study on the relation of discussion activity and revision of critical appraisal papers.

    PubMed

    Koops, Willem J M; van der Vleuten, Cees P M; de Leng, Bas A; Snoeckx, Luc H E H

    2012-08-20

    Medical students in clerkship are continuously confronted with real and relevant patient problems. To support clinical problem solving skills, students perform a Critical Appraisal of a Topic (CAT) task, often resulting in a paper. Because such a paper may contain errors, students could profit from discussion with peers, leading to paper revision. Active peer discussion by a Computer Supported Collaborative Learning (CSCL) environment show positive medical students perceptions on subjective knowledge improvement. High students' activity during discussions in a CSCL environment demonstrated higher task-focussed discussion reflecting higher levels of knowledge construction. However, it remains unclear whether high discussion activity influences students' decisions revise their CAT paper. The aim of this research is to examine whether students who revise their critical appraisal papers after discussion in a CSCL environment show more task-focussed activity and discuss more intensively on critical appraisal topics than students who do not revise their papers. Forty-seven medical students, stratified in subgroups, participated in a structured asynchronous online discussion of individual written CAT papers on self-selected clinical problems. The discussion was structured by three critical appraisal topics. After the discussion, the students could revise their paper. For analysis purposes, all students' postings were blinded and analysed by the investigator, unaware of students characteristics and whether or not the paper was revised. Postings were counted and analysed by an independent rater, Postings were assigned into outside activity, non-task-focussed activity or task-focussed activity. Additionally, postings were assigned to one of the three critical appraisal topics. Analysis results were compared by revised and unrevised papers. Twenty-four papers (51.6%) were revised after the online discussion. The discussions of the revised papers showed significantly higher numbers of postings, more task-focussed activities, and more postings about the two critical appraisal topics: "appraisal of the selected article(s)", and "relevant conclusion regarding the clinical problem". A CSCL environment can support medical students in the execution and critical appraisal of authentic tasks in the clinical workplace. Revision of CAT papers appears to be related to discussions activity, more specifically reflecting high task-focussed activity of critical appraisal topics.

  16. Measuring Moral Distress Among Critical Care Clinicians: Validation and Psychometric Properties of the Italian Moral Distress Scale-Revised.

    PubMed

    Lamiani, Giulia; Setti, Ilaria; Barlascini, Luca; Vegni, Elena; Argentero, Piergiorgio

    2017-03-01

    Moral distress is a common experience among critical care professionals, leading to frustration, withdrawal from patient care, and job abandonment. Most of the studies on moral distress have used the Moral Distress Scale or its revised version (Moral Distress Scale-Revised). However, these scales have never been validated through factor analysis. This article aims to explore the factorial structure of the Moral Distress Scale-Revised and develop a valid and reliable scale through factor analysis. Validation study using a survey design. Eight medical-surgical ICUs in the north of Italy. A total of 184 clinicians (64 physicians, 94 nurses, and 14 residents). The Moral Distress Scale-Revised was translated into Italian and administered along with a measure of depression (Beck Depression Inventory-Second Edition) to establish convergent validity. Exploratory factor analysis was conducted to explore the Moral Distress Scale-Revised factorial structure. Items with low (less than or equal to 0.350) or multiple saturations were removed. The resulting model was tested through confirmatory factor analysis. The Italian Moral Distress Scale-Revised is composed of 14 items referring to four factors: futile care, poor teamwork, deceptive communication, and ethical misconduct. This model accounts for 59% of the total variance and presents a good fit with the data (root mean square error of approximation = 0.06; comparative fit index = 0.95; Tucker-Lewis index = 0.94; weighted root mean square residual = 0.65). The Italian Moral Distress Scale-Revised evinces good reliability (α = 0.81) and moderately correlates with Beck Depression Inventory-Second Edition (r = 0.293; p < 0.001). No significant differences were found in the moral distress total score between physicians and nurses. However, nurses scored higher on futile care than physicians (t = 2.051; p = 0.042), whereas physicians scored higher on deceptive communication than nurses (t = 3.617; p < 0.001). Moral distress was higher for those clinicians considering to give up their position (t = 2.778; p = 0.006). The Italian Moral Distress Scale-Revised is a valid and reliable instrument to assess moral distress among critical care clinicians and develop tailored interventions addressing its different components. Further research could test the generalizability of its factorial structure in other cultures.

  17. [Evaluation of professional knowledge and attitudes on dementia patient care: a trans-cultural adaptation of an evaluation instrument].

    PubMed

    Costa, Gislaine Desani da; Souza, Rosely Almeida; Yamashita, Cintia Hitomi; Pinheiro, Juliane Cibelle Ferreira; Alvarenga, Márcia Regina Martins; Oliveira, Maria Amélia de Campos

    2015-04-01

    To describe the trans-cultural adaptation of the evaluation instrument entitled Atenció Sanitària de Les Demències: la visió de L' Atenció Primarià from Catalan into versions in Portuguese for doctors and nurses. This study evaluates the knowledge and perspectives of these professionals in their treatment of patients diagnosed with dementia in cases of primary care. The adaptation followed internationally accepted rules, which include the following steps: translation, synthesis, back-translation, revision by a committee of specialists, and a test run with 35 practicing doctors and 35 practicing nurses in Brazil's Family Health Strategy (Estratégia Saúde da Família, or ESF in Portuguese). The translation, synthesis, and back-translation steps were performed satisfactorily; only small adjustments were required. The committee of specialists verified the face validity in the version translated into Portuguese, and all of the items that received an agreement score lower than 80% during the initial evaluation were revised. In the test run, the difficulties presented by the health care professionals did not reach 15% of the sample, and therefore, no changes were made. The Portuguese translation of the instrument can be considered semantically, idiomatically, culturally, and conceptually equivalent to the original Catalan version and is, therefore, appropriate for use in Brazil.

  18. Development of user-centered interfaces to search the knowledge resources of the Virginia Henderson International Nursing Library.

    PubMed

    Jones, Josette; Harris, Marcelline; Bagley-Thompson, Cheryl; Root, Jane

    2003-01-01

    This poster describes the development of user-centered interfaces in order to extend the functionality of the Virginia Henderson International Nursing Library (VHINL) from library to web based portal to nursing knowledge resources. The existing knowledge structure and computational models are revised and made complementary. Nurses' search behavior is captured and analyzed, and the resulting search models are mapped to the revised knowledge structure and computational model.

  19. Safety and effectiveness of a polyvinyl alcohol barrier in reducing risks of vascular tissue damage during anterior spinal revision surgery.

    PubMed

    Jeffords, Paul; Li, Jinsheng; Panchal, Deepal; Denoziere, Guilhem; Fetterolf, Donald

    2012-05-01

    This study was conducted as a controlled, prospective investigation to show the safety and efficacy of a polyvinyl alcohol (PVA) device in a sheep model. To evaluate the ability of a permanent PVA hydrogel barrier to reduce the risk of potential vessel damage during anterior vertebral revision surgery, to provide a nonadhesive barrier at the surgical site, and to create a surgical revision plane of dissection. The development of scar tissue and adhesions presents a significant postoperative problem in spine surgery, where adhesion involvement of overlying structures can cause pain, neurovascular complications, and present a difficult surgical environment during revisions. The devices were implanted onto the ventral surface of exposed lumbar intervertebral discs using an anterolateral approach. One disc separated from the study site was also exposed to serve as a control. Three sheep each were then evaluated with an explant procedure at 30 and 90 days. Extensive sampling was undertaken to evaluate gross anatomic, micropathologic, and biochemical environments and properties of the device. The structural properties and appearance of the device remained intact at both 30 and 90 days. The material remained flexible, hydrophilic, and soft, without visible resorption or decomposition. The material was well tolerated by the animal, with minimal histologic signs of inflammation or rejection. Tissue planes were easily able to be localized by the surgeon attempting to locate the prior surgical site at the time of resection. The PVA vessel shield effectively protected the structures overlying the sheep spine during revision, providing a clear dissection plane for resection at repeat surgery. The overlying structures separated from the previous surgical site with no adhesion, and allowed safe separation of adjacent tissues without the use of sharp dissection.

  20. Mass Media and Communication. Second, Revised Edition.

    ERIC Educational Resources Information Center

    Steinberg, Charles S., Ed.

    This revised and enlarged second edition contains sections focusing on a number of mass media: newspapers, the American magazine, motion pictures, broadcasting media, and book publishing. Other section topics include the structure and development of mass communication, public opinion, international communication, the motivation of assent, the…

  1. Programme Reporting Standards (PRS) for improving the reporting of sexual, reproductive, maternal, newborn, child and adolescent health programmes.

    PubMed

    Kågesten, Anna E; Tunçalp, Özge; Portela, Anayda; Ali, Moazzam; Tran, Nhan; Gülmezoglu, A Metin

    2017-08-03

    Information about design, implementation, monitoring and evaluation is central to understand the impact of programmes within the field of sexual, reproductive, maternal, newborn, child and adolescent health (SRMNCAH). Existing reporting guidelines do not orient on reporting of contextual and implementation issues in sufficient detail. We therefore developed Programme Reporting Standards (PRS) to be used by SRMNCAH programme implementers and researchers. Building on the first step of the PRS development (a systematic review to identify reporting items), we conducted a three-round online Delphi consensus survey with experts. Consensus was defined a-priori as 80% agreement of items as essential. This was followed by a technical consultation with a group of experts to refine the items, definitions and their structuring. The revised PRS was piloted to assess its relevance to current SRMNCAH programme reports and identify key issues regarding the use of the PRS. Of the 81 participants invited to the Delphi survey, 20 responded to all three rounds. In the final round, 27 items received consensus as essential; three items were ranked as "borderline" essential; 20 items as supplementary. The items were subsequently revised, followed by a technical consultation with 29 experts to further review and refine the PRS. The feedback resulted in substantial changes to the structure and content of the PRS into 24 items across five domains: Programme overview; Programme components and implementation; Monitoring of Implementation; Evaluation and Results; and Synthesis. This version was used in a piloting exercise, where questions regarding how much information to report and how to comment on the quality of the information reported were addressed. All items were kept in the PRS following the pilot although minor changes were made to the flow and description of items. The PRS 1.0 is the result of a structured, collaborative process, including methods to incorporate input from SRMNCAH stakeholders. The World Health Organization will develop a document that explains the items in greater detail, and will also apply the PRS to on-going initiatives. We welcome continuous input from the field, while it is being used, to improve its relevance and usefulness.

  2. Measuring the impact of multiple sclerosis: Enhancing the measurement performance of the Multiple Sclerosis Impact Scale (MSIS-29) using Rasch Measurement Theory (RMT)

    PubMed Central

    Cleanthous, Sophie; Kinter, Elizabeth; Marquis, Patrick; Petrillo, Jennifer; You, Xiaojun; Wakeford, Craig; Sabatella, Guido

    2017-01-01

    Background Study objectives were to evaluate the Multiple Sclerosis Impact Scale (MSIS-29) and explore an optimized scoring structure based on empirical post-hoc analyses of data from the Phase III ADVANCE clinical trial. Methods ADVANCE MSIS-29 data from six time-points were analyzed in a sample of patients with relapsing–remitting multiple sclerosis (RRMS). Rasch Measurement Theory (RMT) analysis was undertaken to examine three broad areas: sample-to-scale targeting, measurement scale properties, and sample measurement validity. Interpretation of results led to an alternative MSIS-29 scoring structure, further evaluated alongside responsiveness of the original and revised scales at Week 48. Results RMT analysis provided mixed evidence for Physical and Psychological Impact scales that were sub-optimally targeted at the lower functioning end of the scales. Their conceptual basis could also stand to improve based on item fit results. The revised MSIS-29 rescored scales improved but did not resolve the measurement scale properties and targeting of the MSIS-29. In two out of three revised scales, responsiveness analysis indicated strengthened ability to detect change. Conclusion The revised MSIS-29 provides an initial evidence-based improved patient-reported outcome (PRO) instrument for evaluating the impact of MS. Revised scoring improves conceptual clarity and interpretation of scores by refining scale structure to include Symptoms, Psychological Impact, and General Limitations. Clinical trial ADVANCE (ClinicalTrials.gov identifier NCT00906399). PMID:29104758

  3. Measures of gender role attitudes under revision: The example of the German General Social Survey.

    PubMed

    Walter, Jessica Gabriele

    2018-05-01

    Using the example of the German General Social Survey, this study describes how measures of gender role attitudes can be revised. To date measures have focused on the traditional male breadwinner model. However, social developments in female labor force participation, education, and family structure suggest that a revision and adjustment of existing measures are required. First, these measures need to be supplemented with items that represent more egalitarian models of division of labor and the role of the father in the family. Second, the phrasing of existing items needs to be revised. The results of this study indicate that especially regarding the amount of working hours and the age of children, a specification is needed. This study presents a revised measure, to facilitate analyses over time. This revised measure represents two factors: one referring to traditional and one to modern gender role attitudes. Copyright © 2018 Elsevier Inc. All rights reserved.

  4. A six-gene phylogeny provides new insights into choanoflagellate evolution.

    PubMed

    Carr, Martin; Richter, Daniel J; Fozouni, Parinaz; Smith, Timothy J; Jeuck, Alexandra; Leadbeater, Barry S C; Nitsche, Frank

    2017-02-01

    Recent studies have shown that molecular phylogenies of the choanoflagellates (Class Choanoflagellatea) are in disagreement with their traditional taxonomy, based on morphology, and that Choanoflagellatea requires considerable taxonomic revision. Furthermore, phylogenies suggest that the morphological and ecological evolution of the group is more complex than has previously been recognized. Here we address the taxonomy of the major choanoflagellate order Craspedida, by erecting four new genera. The new genera are shown to be morphologically, ecologically and phylogenetically distinct from other choanoflagellate taxa. Furthermore, we name five novel craspedid species, as well as formally describe ten species that have been shown to be either misidentified or require taxonomic revision. Our revised phylogeny, including 18 new species and sequence data for two additional genes, provides insights into the morphological and ecological evolution of the choanoflagellates. We examine the distribution within choanoflagellates of these two additional genes, EF-1A and EFL, closely related translation GTPases which are required for protein synthesis. Mapping the presence and absence of these genes onto the phylogeny highlights multiple events of gene loss within the choanoflagellates. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  5. Level of structural quality and process quality in rural preschool classrooms

    PubMed Central

    Hartman, Suzanne C.; Warash, Barbara G.; Curtis, Reagan; Hirst, Jessica Day

    2017-01-01

    Preschool classrooms with varying levels of structural quality requirements across the state of West Virginia were investigated for differences in measured structural and process quality. Quality was measured using group size, child-to-teacher/staff ratio, teacher education, and the Early Childhood Environmental Rating Scale-Revised (ECERS-R; Harms, T., Clifford, R. M., & Cryer, D. (2005). The early childhood environment rating scale-revised. New York, NY: Teachers College Press). Thirty-six classrooms with less structural quality requirements and 136 with more structural quality requirements were measured. There were significant differences between classroom type, with classrooms with more structural quality requirements having significantly higher teacher education levels and higher environmental rating scores on the ECERS-R subscales of Space and Furnishings, Activities, and Program Structure. Results support previous research that stricter structural state regulations are correlated with higher measured structural and process quality in preschool classrooms. Implications for preschool state quality standards are discussed. PMID:29056814

  6. Lifelong Adaptability: A Cultural Literacy Perspective (Revised Edition)

    ERIC Educational Resources Information Center

    Moyer, John Thayer

    2011-01-01

    This revised 1997 ex post facto study attempted to identify a lifelong adaptability curriculum from a cultural literacy perspective. It investigated students' lifelong adaptability ratings of 15 general school subjects as predicted by family structure, parental age, parental educational level, student cultural literacy, and student gender;…

  7. The Wechsler Memory Scale: A Review of Research.

    ERIC Educational Resources Information Center

    Ivison, David

    1990-01-01

    Research on the standardization, reliability, validity, factor structure, and subtests of the Wechsler Memory Scale (WMS) (1945) and its revised version (1987) is reviewed. Much research relating to the WMS appears to be relevant to the revised version. Use of the instrument in Australia is discussed. (SLD)

  8. A comparative study on assessment procedures and metric properties of two scoring systems of the Coma Recovery Scale-Revised items: standard and modified scores.

    PubMed

    Sattin, Davide; Lovaglio, Piergiorgio; Brenna, Greta; Covelli, Venusia; Rossi Sebastiano, Davide; Duran, Dunja; Minati, Ludovico; Giovannetti, Ambra Mara; Rosazza, Cristina; Bersano, Anna; Nigri, Anna; Ferraro, Stefania; Leonardi, Matilde

    2017-09-01

    The study compared the metric characteristics (discriminant capacity and factorial structure) of two different methods for scoring the items of the Coma Recovery Scale-Revised and it analysed scale scores collected using the standard assessment procedure and a new proposed method. Cross sectional design/methodological study. Inpatient, neurological unit. A total of 153 patients with disorders of consciousness were consecutively enrolled between 2011 and 2013. All patients were assessed with the Coma Recovery Scale-Revised using standard (rater 1) and inverted (rater 2) procedures. Coma Recovery Scale-Revised score, number of cognitive and reflex behaviours and diagnosis. Regarding patient assessment, rater 1 using standard and rater 2 using inverted procedures obtained the same best scores for each subscale of the Coma Recovery Scale-Revised for all patients, so no clinical (and statistical) difference was found between the two procedures. In 11 patients (7.7%), rater 2 noted that some Coma Recovery Scale-Revised codified behavioural responses were not found during assessment, although higher response categories were present. A total of 51 (36%) patients presented the same Coma Recovery Scale-Revised scores of 7 or 8 using a standard score, whereas no overlap was found using the modified score. Unidimensionality was confirmed for both score systems. The Coma Recovery Scale Modified Score showed a higher discriminant capacity than the standard score and a monofactorial structure was also supported. The inverted assessment procedure could be a useful evaluation method for the assessment of patients with disorder of consciousness diagnosis.

  9. CINAHL list of subject headings: a nursing thesaurus revised.

    PubMed

    Fishel, C C; Graham, K E; Greer, D M; Gupta, A D; Lockwood, D K; Prime, E E

    1985-04-01

    The rationale and methods for revising the thesaurus of one of the major health sciences indexing tools are discussed. Computer production of the Cumulative Index to Nursing & Allied Health Literature and the possibility of online access mandated a revision of the list of subject headings. CINAHL has maintained a policy of responding to user needs and to changes in the nursing and allied health literature, and user input was encouraged during revision of the thesaurus. The methods of structural revision are described, and major changes in the thesaurus are detailed. Modification of the thesaurus is expected to have a far-reaching impact on the retrieval of information in nursing and allied health. Nursing and Allied Health (CINAHL) is now available online through DIALOG (file 218) and BRS (access code NAHL).

  10. CINAHL list of subject headings: a nursing thesaurus revised.

    PubMed Central

    Fishel, C C; Graham, K E; Greer, D M; Gupta, A D; Lockwood, D K; Prime, E E

    1985-01-01

    The rationale and methods for revising the thesaurus of one of the major health sciences indexing tools are discussed. Computer production of the Cumulative Index to Nursing & Allied Health Literature and the possibility of online access mandated a revision of the list of subject headings. CINAHL has maintained a policy of responding to user needs and to changes in the nursing and allied health literature, and user input was encouraged during revision of the thesaurus. The methods of structural revision are described, and major changes in the thesaurus are detailed. Modification of the thesaurus is expected to have a far-reaching impact on the retrieval of information in nursing and allied health. Nursing and Allied Health (CINAHL) is now available online through DIALOG (file 218) and BRS (access code NAHL). PMID:3995203

  11. A Multidimensional Diversity‐Oriented Synthesis Strategy for Structurally Diverse and Complex Macrocycles

    PubMed Central

    Nie, Feilin; Kunciw, Dominique L.; Wilcke, David; Stokes, Jamie E.; Galloway, Warren R. J. D.; Bartlett, Sean; Sore, Hannah F.

    2016-01-01

    Abstract Synthetic macrocycles are an attractive area in drug discovery. However, their use has been hindered by a lack of versatile platforms for the generation of structurally (and thus shape) diverse macrocycle libraries. Herein, we describe a new concept in library synthesis, termed multidimensional diversity‐oriented synthesis, and its application towards macrocycles. This enabled the step‐efficient generation of a library of 45 novel, structurally diverse, and highly‐functionalized macrocycles based around a broad range of scaffolds and incorporating a wide variety of biologically relevant structural motifs. The synthesis strategy exploited the diverse reactivity of aza‐ylides and imines, and featured eight different macrocyclization methods, two of which were novel. Computational analyses reveal a broad coverage of molecular shape space by the library and provides insight into how the various diversity‐generating steps of the synthesis strategy impact on molecular shape. PMID:27484830

  12. Functions & Requirements for Debris Removal System Project A-2

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    PRECECHTEL, D.R.

    1999-12-29

    This revision of the Functions and Requirements Document updates the approved Functions and Requirements for Debris Removal Subproject WHC-SD-SNF-FRD-009, Rev. 0. It has been revised in its entirety to reflect the current scope of work for Debris Removal as canisters and lids under the K Basin Projects work breakdown structure (WBS). In this revision the canisters and lids will be consider debris and a new set of Functions and Requirements have been developed to remove the canisters and lids from the basin.

  13. Improved Estimates of Capital Formation in the National Health Expenditure Accounts

    PubMed Central

    Sensenig, Arthur L.; Donahoe, Gerald F.

    2006-01-01

    The National Health Expenditure Accounts (NHEA) were revised with the release of the 2004 estimates. The largest revision was the incorporation of a more comprehensive measure of investment in medical sector capital. The revision raised total health expenditures' share of gross domestic product (GDP) from 15.4 to 15.8 percent in 2003. The improved measure encompasses investment in moveable equipment and software, as well as expenditures for the construction of structures used by the medical sector. PMID:17290665

  14. Psychometric Properties of the Revised Teachers' Attitude toward Inclusion Scale

    ERIC Educational Resources Information Center

    Monsen, Jeremy J.; Ewing, Donna L.; Boyle, James

    2015-01-01

    This paper presents the psychometric properties of a questionnaire measure that updates and extends Larrivee and Cook's (1979) Opinions Relative to Mainstreaming Scale in terms of structure, terminology, and language. The revised scale was tested using a sample of 106 teachers based in inclusive mainstream schools. Using Principal Component…

  15. Psychometric Properties of the Revised Mathematics Anxiety Rating Scale

    ERIC Educational Resources Information Center

    Baloglu, Mustafa; Zelhart, Paul F.

    2007-01-01

    An exploratory factor analysis and several confirmatory analyses were performed to evaluate the factorial structure of the Revised Mathematics Anxiety Rating Scale (RMARS) through the responses of 805 college students. On 559 students' scores, the instrument's construct validity was tested through a confirmatory factor analysis (CFA) and was found…

  16. Chromosomal evolution in Rodentia

    PubMed Central

    Romanenko, S A; Perelman, P L; Trifonov, V A; Graphodatsky, A S

    2012-01-01

    Rodentia is the most species-rich mammalian order and includes several important laboratory model species. The amount of new information on karyotypic and phylogenetic relations within and among rodent taxa is rapidly increasing, but a synthesis of these data is currently lacking. Here, we have integrated information drawn from conventional banding studies, recent comparative painting investigations and molecular phylogenetic reconstructions of different rodent taxa. This permitted a revision of several ancestral karyotypic reconstructions, and a more accurate depiction of rodent chromosomal evolution. PMID:22086076

  17. Synthesis of 6-Substituted-2,4-Diamino-5,6,7,8-Tetrahydropyrimido (4-5-d) Pyrimidines. Revised.

    DTIC Science & Technology

    1981-07-01

    SUPPLEMENTARY NOTES IS. KEY WOROSIUXau on avere aide Inocoeay end Identity by block acemb.,) Tetrahydropyrimido (4,!:-d) pyrimidines Phenylethylamines ...not see continuation of further members of the original target compounds as cost effective . Because of extreme dif- ficulties and time-consuming...have shown significant activity are the 4-Cl (3), 3,4-C1 2 (3,4) and CF3 (5). Spacers such as the Y = -CH2- (6) were also reported to be effective

  18. Configuration Synthesis and Efficient Motion Programming of Robot Manipulators

    DTIC Science & Technology

    1991-03-15

    Gupta and Ma 90- Robotica 8:81-84]. When a set of discrete stations are specified along a robot task path, it becomes necessary to find a related...velocity Jacobian relations for the manipulator [Singh 87-MS Thesis][Gupta and Singh 89- Robotica 7:159-1641 and [Cheng 89-PhD Thesis][Cheng and Gupta...1987; Robotica 7:159-164, 1989 (revised). K. C. Gupta, "Kinematics of a Robot with Continuous Roll Wrist," IEEE J. Robotics and Automation 4(4):440-443

  19. Using sobol sequences for planning computer experiments

    NASA Astrophysics Data System (ADS)

    Statnikov, I. N.; Firsov, G. I.

    2017-12-01

    Discusses the use for research of problems of multicriteria synthesis of dynamic systems method of Planning LP-search (PLP-search), which not only allows on the basis of the simulation model experiments to revise the parameter space within specified ranges of their change, but also through special randomized nature of the planning of these experiments is to apply a quantitative statistical evaluation of influence of change of varied parameters and their pairwise combinations to analyze properties of the dynamic system.Start your abstract here...

  20. Very High Performance High Nitrogen Energetic Ingredients and Energetic Polymers for Structural Components

    DTIC Science & Technology

    2011-12-31

    have developed a vastly improved procedure for synthesis of the n- propyl ester that gives essentially quantitative yield and uses concentrated... Synthesis of n- propyl 4-aminofurazan-3-carboxylate. We next turned our attention to the synthesis of the amide. Again, the literature procedure is... synthesis and chemistry of 3-hydroxymethyl-4-amino[1,2,5]oxadiazole and 5) work on energetic polymers for structural components. 15. SUBJECT TERMS

  1. Synthesis and Structure Property Studies of Toughened Epoxy Resins Via Functionalized Polysiloxanes.

    DTIC Science & Technology

    1987-09-30

    34 87S N4 SYNTHESIS RNO STRUCTURE PROPERTY STUDIES OF OP NDD mEPOXY RESINS YIN FU.. (U) VIROINIR POLYTECHNIC INST OM STNTE UNIY RCKSBURG DEPT OF C.. J...Classification) Synthesis and Structure Property Studies of Toughened Epoxy Resins Via Functionalized Polysiloxanes 12. PERSONALAUTHOR(S) J. 5. HitTIe... Resins , Toughening 19. ABSTRACT (Continue on reverse if necessary and identify by block number) Epoxy resins chemically modified with functionally

  2. Synthesis of Large Quantities of Single-Walled Aluminogermanante Nanotube

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Levard,C.; Rose, J.; Mision, A.

    2008-01-01

    A simple aqueous synthesis yielded about 100 times more structurally well-organized single-walled aluminogermanate nanotubes than previously reported 'standard' procedures. The structure analyses using XRD, IRTF, TEM, and XAS were greatly facilitated by the high concentrations available, and they ascertained the imogolite-like structure of the nanotubes. Simplicity and yield of the synthesis protocol are likely to favor commercial applications of theses materials as well as simplified syntheses of other nanophases.

  3. The revised Bristol Rheumatoid Arthritis Fatigue measures and the Rheumatoid Arthritis Impact of Disease scale: validation in six countries

    PubMed Central

    Kirwan, John; Bode, Christina; Cramp, Fiona; Carmona, Loreto; Dures, Emma; Englbrecht, Matthias; Fransen, Jaap; Greenwood, Rosemary; Hagel, Sofia; van de Laar, Maart; Molto, Anna; Nicklin, Joanna; Petersson, Ingemar F; Redondo, Marta; Schett, Georg; Gossec, Laure

    2018-01-01

    Abstract Objective To evaluate the Bristol Rheumatoid Arthritis Fatigue Multidimensional Questionnaire (BRAF-MDQ), the revised Bristol Rheumatoid Arthritis Numerical Rating Scales (BRAF-NRS V2) and the Rheumatoid Arthritis Impact of Disease (RAID) scale in six countries. Methods We surveyed RA patients in France, Germany, The Netherlands, Spain, Sweden and the UK, including the HAQ, 36-item Short Form Health Survey (SF-36) and potential revisions of the BRAF-NRS coping and Spanish RAID coping items. Factor structure and internal consistency were examined by factor analysis and Cronbach’s α and construct validity by Spearman’s correlation. Results A total of 1276 patients participated (76% female, 25% with a disease duration <5 years, median HAQ 1.0). The original BRAF-MDQ four-factor structure and RAID single-factor structure were confirmed in every country with ⩾66% of variation in items explained by each factor and all item factor loadings of 0.71–0.98. Internal consistency for the BRAF-MDQ total and subscales was a Cronbach’s α of 0.75–0.96 and for RAID, 0.93–0.96. Fatigue construct validity was shown for the BRAF-MDQ and BRAF-NRS severity and effect scales, correlated internally with SF-36 vitality and with RAID fatigue (r = 0.63–0.93). Broader construct validity for the BRAFs and RAID was shown by correlation with each other, HAQ and SF-36 domains (r = 0.46–0.82), with similar patterns in individual countries. The revised BRAF-NRS V2 Coping item had stronger validity than the original in all analyses. The revised Spanish RAID coping item performed as well as the original. Conclusion Across six European countries, the BRAF-MDQ identifies the same four aspects of fatigue, and along with the RAID, shows strong factor structure and internal consistency and moderate–good construct validity. The revised BRAF-NRS V2 shows improved construct validity and replaces the original. PMID:29087507

  4. The revised Bristol Rheumatoid Arthritis Fatigue measures and the Rheumatoid Arthritis Impact of Disease scale: validation in six countries.

    PubMed

    Hewlett, Sarah; Kirwan, John; Bode, Christina; Cramp, Fiona; Carmona, Loreto; Dures, Emma; Englbrecht, Matthias; Fransen, Jaap; Greenwood, Rosemary; Hagel, Sofia; van de Laar, Maart; Molto, Anna; Nicklin, Joanna; Petersson, Ingemar F; Redondo, Marta; Schett, Georg; Gossec, Laure

    2018-02-01

    To evaluate the Bristol Rheumatoid Arthritis Fatigue Multidimensional Questionnaire (BRAF-MDQ), the revised Bristol Rheumatoid Arthritis Numerical Rating Scales (BRAF-NRS V2) and the Rheumatoid Arthritis Impact of Disease (RAID) scale in six countries. We surveyed RA patients in France, Germany, The Netherlands, Spain, Sweden and the UK, including the HAQ, 36-item Short Form Health Survey (SF-36) and potential revisions of the BRAF-NRS coping and Spanish RAID coping items. Factor structure and internal consistency were examined by factor analysis and Cronbach's α and construct validity by Spearman's correlation. A total of 1276 patients participated (76% female, 25% with a disease duration <5 years, median HAQ 1.0). The original BRAF-MDQ four-factor structure and RAID single-factor structure were confirmed in every country with ⩾66% of variation in items explained by each factor and all item factor loadings of 0.71-0.98. Internal consistency for the BRAF-MDQ total and subscales was a Cronbach's α of 0.75-0.96 and for RAID, 0.93-0.96. Fatigue construct validity was shown for the BRAF-MDQ and BRAF-NRS severity and effect scales, correlated internally with SF-36 vitality and with RAID fatigue (r = 0.63-0.93). Broader construct validity for the BRAFs and RAID was shown by correlation with each other, HAQ and SF-36 domains (r = 0.46-0.82), with similar patterns in individual countries. The revised BRAF-NRS V2 Coping item had stronger validity than the original in all analyses. The revised Spanish RAID coping item performed as well as the original. Across six European countries, the BRAF-MDQ identifies the same four aspects of fatigue, and along with the RAID, shows strong factor structure and internal consistency and moderate-good construct validity. The revised BRAF-NRS V2 shows improved construct validity and replaces the original. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Rheumatology.

  5. The revised HSE fatigue guidance

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stacey, A.; Sharp, J.V.

    1995-12-31

    Fatigue cracking has been a principal cause of damage to North Sea structures and consequently considerable attention has been given to the development of guidance for the prediction of fatigue performance. The fatigue guidance of the Offshore Safety Division of the Health and Safety Executive (HSE) was recently revised and published, following a significant offshore industry review in the period 1987 to 1990, and is based on the results of a considerable amount of research and development work on the fatigue behavior of welded tubular and plated joints. As a result of this review, the revised fatigue guidance incorporates severalmore » new clauses and recommendations. The revised recommendations apply to joint classification, basic design S-N curves for welded joints and cast or forged steel components, the thickness effect, the effects of environment and the treatment of low and high stress ranges. Additionally, a new appendix on the derivation of stress concentration factors is included. The new clauses cover high strength steels, bolts and threaded connectors, moorings, repaired joints and the use of fracture mechanics analysis. This paper presents an overview of the revisions to the fatigue guidance, the associated background technical information and aspects of the fatigue behavior of offshore structures which are considered to require further investigation. 67 refs., 7 figs., 8 tabs.« less

  6. Knowledge-Directed Theory Revision

    NASA Astrophysics Data System (ADS)

    Ali, Kamal; Leung, Kevin; Konik, Tolga; Choi, Dongkyu; Shapiro, Dan

    Using domain knowledge to speed up learning is widely accepted but theory revision of such knowledge continues to use general syntactic operators. Using such operators for theory revision of teleoreactive logic programs is especially expensive in which proof of a top-level goal involves playing a game. In such contexts, one should have the option to complement general theory revision with domain-specific knowledge. Using American football as an example, we use Icarus' multi-agent teleoreactive logic programming ability to encode a coach agent whose concepts correspond to faults recognized in execution of the play and whose skills correspond to making repairs in the goals of the player agents. Our results show effective learning using as few as twenty examples. We also show that structural changes made by such revision can produce performance gains that cannot be matched by doing only numeric optimization.

  7. Toward A New Evolutionary Synthesis.

    PubMed

    Flannery, Michael A

    2017-01-01

    This essay responds to Peter T. Saunders's call to go Beyond the neo-Darwinist Paradigm. While there is much to commend in his analysis, especially his suggestion that the extended evolutionary synthesis (EES) may not go far enough, he leaves the question of whether this should involve mere revision or total replacement open. A historiographical review reveals significant problems stemming from certain positivist assumptions and commitments within neo-Darwinian orthodoxy and the EES over and above any scientific considerations. As such, mere tweaking of the existing paradigm or its extension will do little to remedy the intellectual prejudices currently plaguing it. A complete overhaul is suggested by applying the López Ontological Demarcation Design (LODD) principle with biology in a multidisciplinary, non-reductionist philosophical framework. Building on the concept of Organismic-Systems Biology (OSB), a component of General Systems Theory (GTS) associated with polymathic biologist Ludwig von Bertalanffy (1901-1972), and cosmic evolution (CE) proposed by UCLA philosopher John Elof Boodin (1869-1950), the outline of a new evolutionary synthesis is offered as a prolegomenon to further study and evaluation. Copyright: © 2016 by Fabrizio Serra editore, Pisa · Roma.

  8. Diversity-Oriented Synthesis as a Strategy for Fragment Evolution against GSK3β.

    PubMed

    Wang, Yikai; Wach, Jean-Yves; Sheehan, Patrick; Zhong, Cheng; Zhan, Chenyang; Harris, Richard; Almo, Steven C; Bishop, Joshua; Haggarty, Stephen J; Ramek, Alexander; Berry, Kayla N; O'Herin, Conor; Koehler, Angela N; Hung, Alvin W; Young, Damian W

    2016-09-08

    Traditional fragment-based drug discovery (FBDD) relies heavily on structural analysis of the hits bound to their targets. Herein, we present a complementary approach based on diversity-oriented synthesis (DOS). A DOS-based fragment collection was able to produce initial hit compounds against the target GSK3β, allow the systematic synthesis of related fragment analogues to explore fragment-level structure-activity relationship, and finally lead to the synthesis of a more potent compound.

  9. Total synthesis of TMG-chitotriomycin based on an automated electrochemical assembly of a disaccharide building block.

    PubMed

    Isoda, Yuta; Sasaki, Norihiko; Kitamura, Kei; Takahashi, Shuji; Manmode, Sujit; Takeda-Okuda, Naoko; Tamura, Jun-Ichi; Nokami, Toshiki; Itoh, Toshiyuki

    2017-01-01

    The total synthesis of TMG-chitotriomycin using an automated electrochemical synthesizer for the assembly of carbohydrate building blocks is demonstrated. We have successfully prepared a precursor of TMG-chitotriomycin, which is a structurally-pure tetrasaccharide with typical protecting groups, through the methodology of automated electrochemical solution-phase synthesis developed by us. The synthesis of structurally well-defined TMG-chitotriomycin has been accomplished in 10-steps from a disaccharide building block.

  10. Developmentally Regulated Sphingolipid Synthesis in African Trypanosomes

    PubMed Central

    Sutterwala, Shaheen S.; Hsu, Fong Fu; Sevova, Elitza S.; Schwartz, Kevin J.; Zhang, Kai; Key, Phillip; Turk, John; Beverley, Stephen M.; Bangs, James D.

    2008-01-01

    Sphingolipids are essential components of eukaryotic membranes, and many unicellular eukaryotes, including kinetoplastid protozoa, are thought to synthesize exclusively inositol phosphorylceramide (IPC). Here we characterize sphingolipids from Trypanosoma brucei, and a trypanosome sphingolipid synthase gene family (TbSLS1-4) that is orthologous to Leishmania IPC synthase. Procyclic trypanosomes contain IPC, but also sphingomyelin, while surprisingly bloodstream stage parasites contain sphingomyelin and ethanolamine phosphorylceramide (EPC), but no detectable IPC. In vivo fluorescent ceramide labeling confirmed stage specific biosynthesis of both sphingomyelin and IPC. Expression of TbSLS4 in Leishmania resulted in production of sphingomyelin and EPC suggesting that the TbSLS gene family has bi-functional synthase activity. RNAi silencing of TbSLS1-4 in bloodstream trypanosomes led to rapid growth arrest and eventual cell death. Ceramide levels were increased >3-fold by silencing suggesting a toxic downstream effect mediated by this potent intracellular messenger. Topology predictions support a revised six transmembrane domain model for the kinetoplastid sphingolipid synthases consistent with the proposed mammalian SM synthase structure. This work reveals novel diversity and regulation in sphingolipid metabolism in this important group of human parasites. PMID:18699867

  11. Long-Term Plasticity of Neurotransmitter Release: Emerging Mechanisms and Contributions to Brain Function and Disease.

    PubMed

    Monday, Hannah R; Younts, Thomas J; Castillo, Pablo E

    2018-04-25

    Long-lasting changes of brain function in response to experience rely on diverse forms of activity-dependent synaptic plasticity. Chief among them are long-term potentiation and long-term depression of neurotransmitter release, which are widely expressed by excitatory and inhibitory synapses throughout the central nervous system and can dynamically regulate information flow in neural circuits. This review article explores recent advances in presynaptic long-term plasticity mechanisms and contributions to circuit function. Growing evidence indicates that presynaptic plasticity may involve structural changes, presynaptic protein synthesis, and transsynaptic signaling. Presynaptic long-term plasticity can alter the short-term dynamics of neurotransmitter release, thereby contributing to circuit computations such as novelty detection, modifications of the excitatory/inhibitory balance, and sensory adaptation. In addition, presynaptic long-term plasticity underlies forms of learning and its dysregulation participates in several neuropsychiatric conditions, including schizophrenia, autism, intellectual disabilities, neurodegenerative diseases, and drug abuse. Expected final online publication date for the Annual Review of Neuroscience Volume 41 is July 8, 2018. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

  12. [Validating an instrument for measuring the perceived quality of services received by people using hospitals in Colombia].

    PubMed

    Cabrera-Arana, Gustavo A; Londoño-Pimienta, Jaime L; Bello-Parías, León D

    2008-01-01

    Validating an instrument for measuring the perceived quality of services received by people using hospitals forming part of the Colombian Ministry of Social Protection's restructuring, redesigning and modernisation programme for health-service providing networks. Sánchez and Echeverri's guidelines for validating health quality measurement scales were followed due to the lack of a valid instrument for doing this in Colombia. Conceptual synthesis led to identifying a structure of constituent indicators, domains and sub-domains regarding the perception of health service quality. A list of reactions (having a scale for categorising the replies) was analysed according to the validity of appearance, construct, criteria and utility as criteria for sensitivity and usefulness. Successive revisions and three rounds of field-trials led to producing PECASUSS, an acronym given to the instrument for measuring users' perception of health service quality (Percepción de Calidad Según Usuarios de Servicios de Salud). The guidelines effectively orientated the validation of the instrument required for measuring the perceived quality of health services received by people using hospitals forming part of the programme.

  13. Total Synthesis of Bryostatins. Development of Methodology for Atom-Economic and Stereoselective Synthesis of the C-ring Subunit

    PubMed Central

    Trost, Barry M.; Frontier, Alison J.; Thiel, Oliver R.; Yang, Hanbiao; Dong, Guangbin

    2012-01-01

    Bryostatins, a family of structurally complicated macrolides, exhibit an exceptional range of biological activities. The limited availability and structural complexity of these molecules makes development of an efficient total synthesis particularly important. This article describes our initial efforts towards the total synthesis of bryostatins, in which chemoselective and atom-economical methods for stereoselective assembly of the C-ring subunit were developed. A Pd-catalyzed tandem alkyne-alkyne coupling/6-endo-dig cyclization sequence was explored and successfully pursued in the synthesis of a dihydropyran ring system. Elaboration of this methodology ultimately led to a concise synthesis of the C-ring subunit of bryostatins. PMID:21793057

  14. Confirming the Structural Validity of the My Class Inventory -- Short Form Revised

    ERIC Educational Resources Information Center

    Mariani, Melissa; Villares, Elizabeth; Sink, Christopher A.; Colvin, Kimberly; Kuba, Summer Perhay

    2015-01-01

    Researchers analyzed data collected from elementary school students (N = 893) to further establish the psychometric soundness of the My Class Inventory--Short Form Revised (MCI-SFR). A confirmatory factor analysis was conducted resulting in a good fit for a four-factor model, which corresponds to the instrument's four scales (Cohesion,…

  15. Structural Equation Analysis of the Wechsler Adult Intelligence Scale-Revised in a Normal Elderly Sample.

    ERIC Educational Resources Information Center

    Burton, D. Bradley; And Others

    1994-01-01

    A maximum-likelihood confirmatory factor analysis was performed by applying LISREL VII to the Wechsler Adult Intelligence Scale-Revised results of a normal elderly sample of 225 adults. Results indicate that a three-factor model fits best across all sample combinations. A mild gender effect is discussed. (SLD)

  16. 75 FR 10701 - Airworthiness Directives; BAE SYSTEMS (Operations) Limited Model BAe 146 Airplanes and Model Avro...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-09

    ... Limitations Section (ALS) of the Instructions for Continued Airworthiness to incorporate life limits for... existing AD to continue to require revising the Airworthiness Limitations Section (ALS) of the Instructions... fatigue cracking in certain structures. The original NPRM also proposed to require revising the ALS of the...

  17. From Freud to Feminist Personality Theory: Getting Here from There.

    ERIC Educational Resources Information Center

    Lerman, Hannah

    Neither Freud's original theories nor modern revisions of psychoanalytic theory serve women well. Because assumptions about the inherent inferiority of women are embedded at the core of the structure of psychoanalytic theory, the theory cannot be adequately revised for women. A new theory is needed which would serve women's interests better.…

  18. Adapting the Revised Self-Leadership Questionnaire to the Portuguese Context

    ERIC Educational Resources Information Center

    Marques-Quinteiro, Pedro; Curral, Luis Alberto; Passos, Ana Margarida

    2012-01-01

    This study aimed to adapt the Revised Self-Leadership Questionnaire (RSLQ) (Houghton and Neck in J Manag Psychol 17(8):672-691, 2002) for the Portuguese population. 720 professionals, and university and post-graduate students participated in this study. The RSLQ factorial structure was accessed through exploratory and multi group confirmatory…

  19. Test Review: An Interview with Amy Gabel--About the WISC-V

    ERIC Educational Resources Information Center

    Greathouse, Dan; Shaughnessy, Michael F.

    2016-01-01

    Whenever a major intelligence or achievement test is revised, there is always renewed interest in the underlying structure of the test as well as a renewed interest in the scoring, administration, and interpretation changes. In this interview, Amy Gabel discusses the most recent revision of the "Wechsler Intelligence Scale for Children-Fifth…

  20. World Problems in the Classroom. Educational Studies and Documents. Revised Edition.

    ERIC Educational Resources Information Center

    Abraham, Herbert J.

    The purpose of this revised publication is to provide secondary teachers with practical suggestions on teaching about the United Nations system in conjunction with contemporary world problems and issues. Part One describes the foundation of the United Nations and discusses its purposes, members, and structure. Chapters three through 14, which…

  1. Revising explanatory models to accommodate anomalous genetic phenomena: Problem solving in the context of discovery

    NASA Astrophysics Data System (ADS)

    Hafner, Robert; Stewart, Jim

    Past problem-solving research has provided a basis for helping students structure their knowledge and apply appropriate problem-solving strategies to solve problems for which their knowledge (or mental models) of scientific phenomena is adequate (model-using problem solving). This research examines how problem solving in the domain of Mendelian genetics proceeds in situations where solvers' mental models are insufficient to solve problems at hand (model-revising problem solving). Such situations require solvers to use existing models to recognize anomalous data and to revise those models to accommodate the data. The study was conducted in the context of 9-week high school genetics course and addressed: the heuristics charactenstic of successful model-revising problem solving: the nature of the model revisions, made by students as well as the nature of model development across problem types; and the basis upon which solvers decide that a revised model is sufficient (that t has both predictive and explanatory power).

  2. Genetics Home Reference: TRNT1 deficiency

    MedlinePlus

    ... in the production (synthesis) of other proteins. During protein synthesis, a molecule called transfer RNA (tRNA) helps assemble ... thought to be less able to participate in protein synthesis. Researchers suspect that protein synthesis in cellular structures ...

  3. The revised APTA code of ethics for the physical therapist and standards of ethical conduct for the physical therapist assistant: theory, purpose, process, and significance.

    PubMed

    Swisher, Laura Lee; Hiller, Peggy

    2010-05-01

    In June 2009, the House of Delegates (HOD) of the American Physical Therapy Association (APTA) passed a major revision of the APTA Code of Ethics for physical therapists and the Standards of Ethical Conduct for the Physical Therapist Assistant. The revised documents will be effective July 1, 2010. The purposes of this article are: (1) to provide a historical, professional, and theoretical context for this important revision; (2) to describe the 4-year revision process; (3) to examine major features of the documents; and (4) to discuss the significance of the revisions from the perspective of the maturation of physical therapy as a doctoring profession. PROCESS OF REVISION: The process for revision is delineated within the context of history and the Bylaws of APTA. FORMAT, STRUCTURE, AND CONTENT OF REVISED CORE ETHICS DOCUMENTS: The revised documents represent a significant change in format, level of detail, and scope of application. Previous APTA Codes of Ethics and Standards of Ethical Conduct for the Physical Therapist Assistant have delineated very broad general principles, with specific obligations spelled out in the Ethics and Judicial Committee's Guide for Professional Conduct and Guide for Conduct of the Physical Therapist Assistant. In contrast to the current documents, the revised documents address all 5 roles of the physical therapist, delineate ethical obligations in organizational and business contexts, and align with the tenets of Vision 2020. The significance of this revision is discussed within historical parameters, the implications for physical therapists and physical therapist assistants, the maturation of the profession, societal accountability and moral community, potential regulatory implications, and the inclusive and deliberative process of moral dialogue by which changes were developed, revised, and approved.

  4. The incorporation of plotting capability into the Unified Subsonic Supersonic Aerodynamic Analysis program, version B

    NASA Technical Reports Server (NTRS)

    Winter, O. A.

    1980-01-01

    The B01 version of the United Subsonic Supersonic Aerodynamic Analysis program is the result of numerous modifications and additions made to the B00 version. These modifications and additions affect the program input, its computational options, the code readability, and the overlay structure. The following are described: (1) the revised input; (2) the plotting overlay programs which were also modified, and their associated subroutines, (3) the auxillary files used by the program, the revised output data; and (4) the program overlay structure.

  5. Total synthesis of TMG-chitotriomycin based on an automated electrochemical assembly of a disaccharide building block

    PubMed Central

    Isoda, Yuta; Sasaki, Norihiko; Kitamura, Kei; Takahashi, Shuji; Manmode, Sujit; Takeda-Okuda, Naoko; Tamura, Jun-ichi

    2017-01-01

    The total synthesis of TMG-chitotriomycin using an automated electrochemical synthesizer for the assembly of carbohydrate building blocks is demonstrated. We have successfully prepared a precursor of TMG-chitotriomycin, which is a structurally-pure tetrasaccharide with typical protecting groups, through the methodology of automated electrochemical solution-phase synthesis developed by us. The synthesis of structurally well-defined TMG-chitotriomycin has been accomplished in 10-steps from a disaccharide building block. PMID:28684973

  6. Total synthesis of the proposed structure of trichodermatide A.

    PubMed

    Myers, Eddie; Herrero-Gómez, Elena; Albrecht, Irina; Lachs, Jennifer; Mayer, Peter; Hanni, Matti; Ochsenfeld, Christian; Trauner, Dirk

    2014-10-17

    A short total synthesis of the published structure of racemic trichodermatide A is reported. Our synthesis involves a Knoevenagel condensation/Michael addition sequence, followed by the formation of tricyclic hexahydroxanthene-dione and a diastereoselective bis-hydroxylation. The final product, the structure of which was confirmed by X-ray crystallography, has NMR spectra that are very similar, but not identical, to those of the isolated natural product. Quantum chemically computed (13)C shifts agree well with the present NMR measurements.

  7. Revised Atomistic Models of the Crystal Structure of C-S-H with high C/S Ratio

    NASA Astrophysics Data System (ADS)

    Kovačević, Goran; Nicoleau, Luc; Nonat, André; Veryazov, Valera

    2016-09-01

    The atomic structure of calcium-silicate-hydrate (C1.67-S-Hx) has been studied. Atomistic C-S-H models suggested in our previous study have been revised in order to perform a direct comparison of energetic stability of the different structures. An extensive set of periodic structures of C-S-H with variation of water content was created, and then optimized using molecular dynamics with reactive force field ReaxFF and quantum chemical semiempirical method PM6. All models show organization of water molecules inside the structure of C-S-H. The new geometries of C-S-H, reported in this paper, show lower relative energy with respect to the geometries from the original definition of C-S-H models. Model that corresponds to calcium enriched tobermorite structure has the lowest relative energy and the density closest to the experimental values.

  8. Structure and functional dynamics of the mitochondrial Fe/S cluster synthesis complex.

    PubMed

    Boniecki, Michal T; Freibert, Sven A; Mühlenhoff, Ulrich; Lill, Roland; Cygler, Miroslaw

    2017-11-03

    Iron-sulfur (Fe/S) clusters are essential protein cofactors crucial for many cellular functions including DNA maintenance, protein translation, and energy conversion. De novo Fe/S cluster synthesis occurs on the mitochondrial scaffold protein ISCU and requires cysteine desulfurase NFS1, ferredoxin, frataxin, and the small factors ISD11 and ACP (acyl carrier protein). Both the mechanism of Fe/S cluster synthesis and function of ISD11-ACP are poorly understood. Here, we present crystal structures of three different NFS1-ISD11-ACP complexes with and without ISCU, and we use SAXS analyses to define the 3D architecture of the complete mitochondrial Fe/S cluster biosynthetic complex. Our structural and biochemical studies provide mechanistic insights into Fe/S cluster synthesis at the catalytic center defined by the active-site Cys of NFS1 and conserved Cys, Asp, and His residues of ISCU. We assign specific regulatory rather than catalytic roles to ISD11-ACP that link Fe/S cluster synthesis with mitochondrial lipid synthesis and cellular energy status.

  9. Steps through the revision process of reproductive health sections of ICD-11.

    PubMed

    Chou, Doris; Tunçalp, Özge; Hotamisligil, Selen; Norman, Jane; Say, Lale; Volkmer, Björn; Pattinson, Bob; Rooney, Cleo; Serour, Gamal; de Mouzon, Jacques; Gardosi, Jason; Thueroff, Joachim; Mark, Morgan; D'Hooghe, Thomas

    2012-01-01

    In 2007, the WHO initiated an organizational structure for the 11th revision of the International Classification of Diseases (ICD). Effective deployment of ICD-derived tools facilitates the use and collection of health information in a variety of resource settings, promoting quantitatively informed decisions. They also facilitate comparison of disease incidence and outcomes between different countries and different health care systems around the world. The Department of Reproductive Health and Research (RHR) coordinates the revision of chapters 14 (diseases of the genitourinary system), 15 (pregnancy, childbirth, and puerperium), and 16 (conditions originating in the perinatal period). RHR convened a technical advisory group (TAG), the Genito-Urinary Reproductive Medicine (GURM) TAG, for the ICD revision. The TAG's work reflects the collective understanding of sexual and reproductive health and is now available for review within the ICD-11 revision process. Copyright © 2012 S. Karger AG, Basel.

  10. Programmable Triplet Formation and Decay in Metal-Organic Chromophores

    DTIC Science & Technology

    2011-12-13

    potential applications in optical limiting molecules has resulted in the synthesis and characterization of many new classes of chromophores in...Castellano, F.N. Inorg. Chem. 2006, 45, 4304-4306. Inorganic Chemistry Cover May 29, 2006. The synthesis , structural characterization, and...The synthesis , photophysics, electronic structure, and electrochemical characterization of 4′-tert- butylacetylene-2,2′:6′,2″-terpyridineplatinum(II

  11. Bone Remodeling in Acetabular Reconstruction Using a Kerboull-Type Reinforcement Device and Structural Bone-Grafting in Total Hip Arthroplasty.

    PubMed

    Oe, Kenichi; Iida, Hirokazu; Tsuda, Kohei; Nakamura, Tomohisa; Okamoto, Naofumi; Ueda, Yusuke

    2017-03-01

    The purpose of this study was to identify the long-term durability of the Kerboull-type reinforcement device (KT plate) in acetabular reconstruction for massive bone defects, assessing the remodeling of structural bone grafts. This study retrospectively evaluated 106 hips that underwent acetabular reconstruction using a KT plate between November 2000 and December 2010. Thirty-eight primary total hip arthoplasties (THAs) and 68 revised THAs were performed, and the mean duration of clinical follow-up was 8 years (5-14 years). Regarding reconstructing the acetabular bone defects, autografts were used in 37 hips, allografts in 68 hips, and A-W glass ceramics in 2 hips. One hip exhibited radiological migration and no revision for aseptic loosening. The mean Merle d'Aubigné Clinical Score improved from 7.5 points (4-12 points) preoperatively to 10.9 points (9-18 points) at the last follow-up. The Kaplan-Meier survival rate for radiological migration of primary and revised THAs at 10 years was 100% and 97% (95% confidence interval: 96%-100%), respectively. Bone remodeling was evaluated using the radiological demarcation at the bone-to-bone interface, and an improvement of 100% in primary THAs and 94% in revised THAs was observed. For massive bone defects, acetabular reconstruction using the KT plate with a structural bone grafting can yield successful results. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Psychometric properties of the revised conscientiousness dimension of Inventário Dimensional Clínico da Personalidade (IDCP).

    PubMed

    Carvalho, Lucas de Francisco; Souza, Bruna Daniela Balbino de; Primi, Ricardo

    2014-01-01

    This study investigated the psychometric properties of the revised scale of conscientiousness of a clinical personality inventory (Inventário Dimensional Clínico da Personalidade, IDCP). One hundred and twenty participants (68 women; 56.7%) aged 18 to 53 years (mean = 22.58, standard deviation = 6.19) were recruited by convenience and answered the IDCP and the NEO Personality Inventory - Revised. The analysis of internal structure, association with external variables and reliability of the dimension under review confirmed its validity. The psychometric characteristics of the revised dimension seem to be more adequate than those of the original version and more focused on pathological functioning, which was expected and desirable.

  13. The FORTRAN static source code analyzer program (SAP) user's guide, revision 1

    NASA Technical Reports Server (NTRS)

    Decker, W.; Taylor, W.; Eslinger, S.

    1982-01-01

    The FORTRAN Static Source Code Analyzer Program (SAP) User's Guide (Revision 1) is presented. SAP is a software tool designed to assist Software Engineering Laboratory (SEL) personnel in conducting studies of FORTRAN programs. SAP scans FORTRAN source code and produces reports that present statistics and measures of statements and structures that make up a module. This document is a revision of the previous SAP user's guide, Computer Sciences Corporation document CSC/TM-78/6045. SAP Revision 1 is the result of program modifications to provide several new reports, additional complexity analysis, and recognition of all statements described in the FORTRAN 77 standard. This document provides instructions for operating SAP and contains information useful in interpreting SAP output.

  14. The New Unified Theory of ATP Synthesis/Hydrolysis and Muscle Contraction, Its Manifold Fundamental Consequences and Mechanistic Implications and Its Applications in Health and Disease

    PubMed Central

    Nath, Sunil

    2008-01-01

    Complete details of the thermodynamics and molecular mechanisms of ATP synthesis/hydrolysis and muscle contraction are offered from the standpoint of the torsional mechanism of energy transduction and ATP synthesis and the rotation-uncoiling-tilt (RUT) energy storage mechanism of muscle contraction. The manifold fundamental consequences and mechanistic implications of the unified theory for oxidative phosphorylation and muscle contraction are explained. The consistency of current mechanisms of ATP synthesis and muscle contraction with experiment is assessed, and the novel insights of the unified theory are shown to take us beyond the binding change mechanism, the chemiosmotic theory and the lever arm model. It is shown from first principles how previous theories of ATP synthesis and muscle contraction violate both the first and second laws of thermodynamics, necessitating their revision. It is concluded that the new paradigm, ten years after making its first appearance, is now perfectly poised to replace the older theories. Finally, applications of the unified theory in cell life and cell death are outlined and prospects for future research are explored. While it is impossible to cover each and every specific aspect of the above, an attempt has been made here to address all the pertinent details and what is presented should be sufficient to convince the reader of the novelty, originality, breakthrough nature and power of the unified theory, its manifold fundamental consequences and mechanistic implications, and its applications in health and disease. PMID:19325832

  15. Phellilane L, Sesquiterpene Metabolite of Phellinus linteus: Isolation, Structure Elucidation, and Asymmetric Total Synthesis.

    PubMed

    Ota, Koichiro; Yamazaki, Ikuma; Saigoku, Takahiro; Fukui, Mei; Miyata, Tomoki; Kamaike, Kazuo; Shirahata, Tatsuya; Mizuno, Fumi; Asada, Yoshihisa; Hirotani, Masao; Ino, Chieko; Yoshikawa, Takafumi; Kobayashi, Yoshinori; Miyaoka, Hiroaki

    2017-12-01

    A new cyclopropane-containing sesquiterpenoid, phellilane L (1), was isolated from the medicinal mushroom Phellinus linteus ("Meshimakobu" in Japanese), a member of the Hymenochaetaceae family and a well-known fungus that is widely used in East Asia. The planar structure of 1 was determined on the basis of spectroscopic analysis. The authors achieved the first total synthesis of 1. Our protecting group-free synthesis features a highly stereoselective one-pot synthesis involving an intermolecular alkylation/cyclization/lactonization strategy for construction of the key cyclopropane-γ-lactone intermediate. Additionally, our synthesis determined the absolute configuration of phellilane L (1).

  16. National Curriculum Standards for Social Studies: A Framework for Teaching, Learning, and Assessment

    ERIC Educational Resources Information Center

    National Council for the Social Studies, 2010

    2010-01-01

    The revised standards, like the earlier social studies standards published in 1994, continue to be structured around the ten themes of social studies. However, the revised standards offer a sharper focus on: (1) Purposes; (2) Questions for Exploration; (3) Knowledge: what learners need to understand; (4) Processes: what learners will be capable of…

  17. "What Did I Change and Why Did I Do It?": Young Writers' Revision Practices

    ERIC Educational Resources Information Center

    Dix, Stephanie

    2006-01-01

    The article presents findings from a research project that investigated young, fluent writers' revision practices. The project adopted a qualitative approach, using semi-structured interviews based on the students' written scripts. This article focuses on a small sample of children and profiles the extent of their ability to reflect on their…

  18. The Factor Structure of the CIBS-II-Readiness Assessment

    ERIC Educational Resources Information Center

    Gotch, Chad M.; French, Brian F.

    2011-01-01

    The Brigance Comprehensive Inventory of Basic Skills-II (CIBS-II)-Readiness form is a diagnostic battery intended for children aged 5 and 6 years. The CIBS-II-Readiness is a new version of the CIBS-Revised-Readiness and includes updated normative information on a larger representative sample in comparison to the CIBS-Revised-Readiness. Empirical…

  19. Factorial Structure of the Quick Neurological Screening Test-Revised for Children with Learning Disabilities.

    ERIC Educational Resources Information Center

    Finlayson, Shannon B.; Obrzut, John E.

    1993-01-01

    Administered Quick Neurological Screening Test-Revised (QNST-R) to 122 elementary-aged children diagnosed with learning disabilities. QNST-R appeared to measure primarily lower order sensory perception/processing and fine and gross motoric skills, which are thought presumably to serve as basis for later higher order cognitive functions. Age, but…

  20. Measuring Bystander Attitudes and Behavior to Prevent Sexual Violence

    ERIC Educational Resources Information Center

    McMahon, Sarah; Allen, Christopher T.; Postmus, Judy L.; McMahon, Sheila M.; Peterson, N. Andrew; Lowe Hoffman, Melanie

    2014-01-01

    Objective: The purpose of this study is to further investigate the factor structure and strength of the Bystander Attitude Scale-Revised and Bystander Behavior Scale-Revised (BAS-R and BBS-R). Participants: First-year students (N = 4,054) at a large public university in the Northeast completed a survey in 2010 as part of a larger longitudinal…

  1. Measuring Change in Career Counseling: Validation of the "Career Futures Inventory-Revised"

    ERIC Educational Resources Information Center

    Rottinghaus, Patrick J.; Eshelman, Alec; Gore, Jonathan S.; Keller, Kari J.; Schneider, Madalyn; Harris, Kristine L.

    2017-01-01

    This retrospective chart review study examined the factor structure of the "Career Futures Inventory-Revised" (CFI-R; Rottinghaus et al. in "J Career Assess" 20:123-139, 2012) and its utility as a career counseling outcome measure using a sample of 332 clients from a university career center. The CFI-R examines career agency…

  2. Consumer Education: A Conceptual Structure and Planning Guide for Senior High Schools in Wisconsin.

    ERIC Educational Resources Information Center

    Appleton Public Schools, WI.

    Prepared by junior and senior high teachers, the curriculum guide is an interdisciplinary approach by the business education, home economics, and social studies departments to a consumer education course. The initial development of materials was field tested and revised; a second-year field testing of the revised curriculum and a final analysis…

  3. 75 FR 30287 - Airworthiness Directives; Empresa Brasileira de Aeronautica S.A. (EMBRAER) Model EMB-135BJ...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-01

    ... Limitations Section (ALS) of the Instructions for Continued Airworthiness to incorporate new structural... doing the tasks required by paragraph (f) of the NPRM from 200 flight cycles after revising the ALS to 500 flight cycles after revising the ALS. EMBRAER explains that the extension of the grace period...

  4. Two Revised Measures of Coping for Individuals with Late-Deafness

    ERIC Educational Resources Information Center

    Meyer, Jill M.; Kashubeck-West, Susan; Portela, Lindsay

    2018-01-01

    Purpose: The present study had two goals: (a) to examine the revised structures of these measures to determine the reliability and validity when used in a sample of individuals with latedeafness, and (b) to examine differences in coping style in individuals with late-deafness across race, ethnicity, gender, age, socioeconomic status (SES), level…

  5. The Validity of the Psychopathic Personality Inventory-Revised in a Community Sample

    ERIC Educational Resources Information Center

    Uzieblo, Katarzyna; Verschuere, Bruno; Van den Bussche, Eva; Crombez, Geert

    2010-01-01

    Research on the Psychopathic Personality Inventory-Revised (PPI-R) has revealed two factors: Fearless Dominance, and Self-Centered Impulsivity. This study examined the validity of these PPI-R factors in a community sample (N = 675). First, confirmatory factor analyses did not support the two-factor structure. Second, the PPI-R factors showed good…

  6. Psychometric Characteristics of the Persian Version of the Multidimensional School Anger Inventory-Revised

    ERIC Educational Resources Information Center

    Aryadoust, Vahid; Akbarzadeh, Sanaz; Akbarzedeh, Sara

    2011-01-01

    The Multidimensional School Anger Inventory-Revised (MSAI-R) is a measurement tool to evaluate high school students' anger. Its psychometric features have been tested in the USA, Australia, Japan, Guatemala, and Italy. This study investigates the factor structure and psychometric quality of the Persian version of the MSAI-R using data from an…

  7. 75 FR 6095 - Revision of Area Navigation (RNAV) Route Q-108; Florida

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-08

    ...-0885; Airspace Docket No. 09-ASO-17] Revision of Area Navigation (RNAV) Route Q-108; Florida AGENCY... an error in the legal description for RNAV route Q-108 that was published in the Federal Register on... Area Navigation (RNAV) Route Q-108 in northern Florida by realigning the route structure. In the legal...

  8. Cross-cultural adaptation of the Disability of Arm, Shoulder, and Hand questionnaire: Spanish for Puerto Rico Version

    PubMed Central

    Mulero-Portela, Ana L.; Colón-Santaella, Carmen L.; Cruz-Gomez, Cynthia

    2010-01-01

    The purpose of this study was to perform a cross-cultural adaptation of the Disability of Arm, Shoulder, and Hand (DASH) questionnaire to Spanish for Puerto Rico. Five steps were followed for the cross-cultural adaptation: forward translations into Spanish for Puerto Rico, synthesis of the translations, back translations into English, revision by an expert committee, and field test of the prefinal version. Psychometric characteristics of reliability and construct validity were evaluated for the final version. Internal consistency of the final version was high (Cronbach's α = 0.97) and item-to-total correlations were moderate (range from 0.44 to 0.85). Construct validity was evaluated by correlating the DASH with the scales of the Functional Assessment of Cancer Therapy - Breast. Fair to moderate correlations found in this study between the DASH and most scales of the Functional Assessment of Cancer Therapy - Breast support the construct validity of the Puerto Rico-Spanish DASH. The final version of the questionnaire was revised and approved by the Institute for Work and Health of Canada. Revisions to the original DASH English version are recommended. This version of the DASH is valid and reliable, and it can be used to evaluate outcomes in both clinical and research settings. PMID:19901616

  9. Synthesis and optimization of four bar mechanism with six design parameters

    NASA Astrophysics Data System (ADS)

    Jaiswal, Ankur; Jawale, H. P.

    2018-04-01

    Function generation is synthesis of mechanism for specific task, involves complexity for specially synthesis above five precision of coupler points. Thus pertains to large structural error. The methodology for arriving to better precision solution is to use the optimization technique. Work presented herein considers methods of optimization of structural error in closed kinematic chain with single degree of freedom, for generating functions like log(x), ex, tan(x), sin(x) with five precision points. The equation in Freudenstein-Chebyshev method is used to develop five point synthesis of mechanism. The extended formulation is proposed and results are obtained to verify existing results in literature. Optimization of structural error is carried out using least square approach. Comparative structural error analysis is presented on optimized error through least square method and extended Freudenstein-Chebyshev method.

  10. Biogenetically-Inspired Total Synthesis of Epidithiodiketopiperazines and Related Alkaloids

    PubMed Central

    2015-01-01

    Conspectus Natural products chemistry has historically been the prime arena for the discovery of new chemical transformations and the fountain of insights into key biological processes. It remains a fervent incubator of progress in the fields of chemistry and biology and an exchange mediating the flow of ideas between these allied fields of science. It is with this ethos that our group has taken an interest in and pursued the synthesis of a complex family of natural products termed the dimeric epipolythiodiketopiperazine (ETP) alkaloids. We present here an Account of the highly complex target molecules to which we pegged our ambitions, our systematic and relentless efforts toward those goals, the chemistry we developed in their pursuit, and the insight we have gained for their translational potential as potent anticancer molecules. The dimeric ETP alkaloids are fungal metabolites that feature a highly complex molecular architecture comprising a densely functionalized core structure with many stereogenic centers, six of which are fully substituted, and a pair of vicinal quaternary carbon stereocenters, decorated on polycyclic architectures in addition to the unique ETP motif that has been recognized as acid-, base-, and redox-sensitive. A cyclo-dipeptide consisting of an essential tryptophan residue and a highly variable ancillary amino acid lies at the core of these structures; investigation of the transformations that take this simplistic core to the complex alkaloids lies at the heart of our research program. The dimeric epidithiodiketopiperazine alkaloids have largely resisted synthesis on account of their complexity since the 1970s when the founding members of this class, chaetocin A (HauserD. et al. Helv. Chim. Acta1970, 53, 10615448218) and verticillin A (KatagiriK. et al. J. Antibiot.1970, 23, 4205465723), were first isolated. This was despite their potent cytotoxic and bacteriostatic activities, which were well appreciated at the time of their discovery. In the past decade, an increasing number of studies have uncovered powerful new biological processes that these molecules can uniquely effect, such as the inhibition of histone methyltransferases by chaetocin A (GreinerD. et al. Nat. Chem. Biol.2005, 1, 14316408017). In fact, the complete collection of hexahydropyrroloindoline alkaloids features a diverse range of potent biological properties including cytotoxic, antitumor, antileukemic, antiviral, antibiotic, and antinematodal activities (JiangC.-S.; GuoY.-W.Mini-Rev. Med. Chem.2011, 11, 72821651467). This mélange of activities is reflective of their structural diversity. Under the precepts of retrobiosynthetic analysis, we have accomplished the syntheses of more than a dozen natural products, including members of the bionectin, calycanthaceous, chaetocin, gliocladin, naseseazine, and verticillin alkaloids. More importantly, these molecules have acted as venerable venues for the development of new strategies to address structural challenges including, but not limited to, C3–C3′ vicinal quaternary centers, heterodimeric linkages, C3–Csp2 linkages, diketopiperazine oxidation, stereoselective thiolation, homologue-specific polysulfidation, and C12-hydroxyl incorporation. Synthesis of these natural products has resulted in the structural confirmation, and sometimes revision such as the case of (+)-naseseazines A and B, as well as access to many plausible biogenetically relevant intermediates and new synthetic ETP derivatives. Furthermore, our studies have paved the way for the formulation of a comprehensive SAR profile and the identification of lead compounds with in vitro subnanomolar IC50’s against a broad range of cancer types. PMID:25843276

  11. Measuring chronic condition self-management in an Australian community: factor structure of the revised Partners in Health (PIH) scale.

    PubMed

    Smith, David; Harvey, Peter; Lawn, Sharon; Harris, Melanie; Battersby, Malcolm

    2017-01-01

    To evaluate the factor structure of the revised Partners in Health (PIH) scale for measuring chronic condition self-management in a representative sample from the Australian community. A series of consultations between clinical groups underpinned the revision of the PIH. The factors in the revised instrument were proposed to be: knowledge of illness and treatment, patient-health professional partnership, recognition and management of symptoms and coping with chronic illness. Participants (N = 904) reporting having a chronic illness completed the revised 12-item scale. Two a priori models, the 4-factor and bi-factor models were then evaluated using Bayesian confirmatory factor analysis (BCFA). Final model selection was established on model complexity, posterior predictive p values and deviance information criterion. Both 4-factor and bi-factor BCFA models with small informative priors for cross-loadings provided an acceptable fit with the data. The 4-factor model was shown to provide a better and more parsimonious fit with the observed data in terms of substantive theory. McDonald's omega coefficients indicated that the reliability of subscale raw scores was mostly in the acceptable range. The findings showed that the PIH scale is a relevant and structurally valid instrument for measuring chronic condition self-management in an Australian community. The PIH scale may help health professionals to introduce the concept of self-management to their patients and provide assessment of areas of self-management. A limitation is the narrow range of validated PIH measurement properties to date. Further research is needed to evaluate other important properties such as test-retest reliability, responsiveness over time and content validity.

  12. Next generation macrocyclic and acyclic cationic lipids for gene transfer: Synthesis and in vitro evaluation.

    PubMed

    Jubeli, Emile; Maginty, Amanda B; Abdul Khalique, Nada; Raju, Liji; Abdulhai, Mohamad; Nicholson, David G; Larsen, Helge; Pungente, Michael D; Goldring, William P D

    2015-10-01

    Previously we reported the synthesis and in vitro evaluation of four novel, short-chain cationic lipid gene delivery vectors, characterized by acyclic or macrocyclic hydrophobic regions composed of, or derived from, two 7-carbon chains. Herein we describe a revised synthesis of an expanded library of related cationic lipids to include extended chain analogues, their formulation with plasmid DNA (pDNA) and in vitro delivery into Chinese hamster ovarian (CHO-K1) cells. The formulations were evaluated against each other based on structural differences in the hydrophobic domain and headgroup. Structurally the library is divided into four sets based on lipids derived from two 7- or two 11-carbon hydrophobic chains, C7 and C11 respectively, which possess either a dimethylamine or a trimethylamine derived headgroup. Each set includes four cationic lipids based on an acyclic or macrocyclic, saturated or unsaturated hydrophobic domain. All lipids were co-formulated with the commercial cationic lipid 1,2-dimyristoyl-sn-glycero-3-ethylphosphocholine (EPC) in a 1:1 molar ratio, along with one of two distinct neutral co-lipids, cholesterol or 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) in an overall cationic-to-neutral lipid molar ratio of 3:2. Binding of lipid formulations with DNA, and packing morphology associated with the individual lipid-DNA complexes were characterized by gel electrophoresis and small angle X-ray diffraction (SAXD), respectively. As a general trend, lipoplex formulations based on mismatched binary cationic lipids, composed of a shorter C7 lipid and the longer lipid EPC (C14), were generally associated with higher transfection efficiency and lower cytotoxicity than their more closely matched C11/EPC binary lipid formulation counterparts. Furthermore, the cyclic lipids gave transfection levels as high as or greater than their acyclic counterparts, and formulations with cholesterol exhibited higher transfection and lower cytotoxicity than those formulated with DOPE. A number of the lipid formulations with cholesterol as co-lipid performed as well as, or better than Lipofectamine 2000™ and EPC, the two positive controls employed in these studies. These results suggest that our novel cyclic and acyclic cationic lipid vectors are effective nonviral gene transfer agents that warrant further investigation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Longevity-modulating effects of symbiosis: insights from Drosophila-Wolbachia interaction.

    PubMed

    Maistrenko, Oleksandr M; Serga, Svitlana V; Vaiserman, Alexander M; Kozeretska, Iryna A

    2016-11-01

    Microbial communities are known to significantly affect various fitness components and survival of their insect hosts, including Drosophila. The composition of symbiotic microbiota has been shown to change with the host's aging. It is unclear whether these changes are caused by the aging process or, vice versa, they affect the host's aging and longevity. Recent findings indicate that fitness and lifespan of Drosophila are affected by endosymbiotic bacteria Wolbachia. These effects, however, are inconsistent and have been reported both to extend and shorten longevity. The main molecular pathways underlying the lifespan-modulating effects of Wolbachia remain unclear, however insulin/insulin-like growth factor, immune deficiency, ecdysteroid synthesis and signaling and c-Jun N-terminal kinase pathways as well as heat shock protein synthesis and autophagy have been proposed to play a role. Here we revise the current evidence that elucidates the impact of Wolbachia endosymbionts on the aging processes in Drosophila.

  14. Seismic analyses of equipment in 2736-Z complex. Revision 1

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ocoma, E.C.

    1995-04-01

    This report documents the structural qualification for the existing equipment when subjected to seismic loading in the Plutonium Storage Complex. It replaces in entirety Revision 0 and reconciles the U.S. Department of Energy (DOE) comments on Revision 0. The Complex consists of 2736-Z Building (plutonium storage vault), 2736-ZA Building (vault ventilation equipment building), and 2736-ZB Building (shipping/receiving, repackaging activities). The existing equipment structurally qualified in this report are the metal storage racks for 7 inch and lard cans in room 2 of Building 2736-Z; the cubicles, can holders and pedestals in rooms 1, 3, and 4 of Building 2736-Z; themore » ventilation duct including exhaust fans/motors, emergency diesel generator, and HEPA filter housing in Building 2736-ZA; the repackaging glovebox in Building 2736-ZB; and the interface duct between Buildings 2736-Z and 2736-ZA.« less

  15. Metallic nanoparticles and their medicinal potential. Part II: aluminosilicates, nanobiomagnets, quantum dots and cochleates.

    PubMed

    Loomba, Leena; Scarabelli, Tiziano

    2013-09-01

    Metallic miniaturization techniques have taken metals to nanoscale size where they can display fascinating properties and their potential applications in medicine. In recent years, metal nanoparticles such as aluminium, silicon, iron, cadmium, selenium, indium and calcium, which find their presence in aluminosilicates, nanobiomagnets, quantum dots (Q-dots) and cochleates, have caught attention of medical industries. The increasing impact of metallic nanoparticles in life sciences has significantly advanced the production techniques for these nanoparticles. In this Review, the various methods for the synthesis of nanoparticles are outlined, followed by their physicochemical properties, some recent applications in wound healing, diagnostic imaging, biosensing, assay labeling, antimicrobial activity, cancer therapy and drug delivery are listed, and finally their toxicological impacts are revised. The first half of this article describes the medicinal uses of two noble nanoparticles - gold and silver. This Review provides further information on the ability of aluminum, silicon, iron, selenium, indium, calcium and zinc to be used as nanoparticles in biomedical sciences. Aluminosilicates find their utility in wound healing and antibacterial growth. Iron-oxide nanoparticles enhance the properties of MRI contrast agents and are also used as biomagnets. Cadmium, selenium, tellurium and indium form the core nanostructures of tiny Q-dots used in cellular assay labeling, high-resolution cell imaging and biosensing. Cochleates have the bivalent nano ions calcium, magnesium or zinc imbedded in their structures and are considered to be highly effective agents for drug and gene delivery. The aluminosilicates, nanobiomagnets, Q-dots and cochleates are discussed in the light of their properties, synthesis and utility.

  16. Plant cellulose synthesis: CESA proteins crossing kingdoms.

    PubMed

    Kumar, Manoj; Turner, Simon

    2015-04-01

    Cellulose is a biopolymer of considerable economic importance. It is synthesised by the cellulose synthase complex (CSC) in species ranging from bacteria to higher plants. Enormous progress in our understanding of bacterial cellulose synthesis has come with the recent publication of both the crystal structure and biochemical characterisation of a purified complex able to synthesis cellulose in vitro. A model structure of a plant CESA protein suggests considerable similarity between the bacterial and plant cellulose synthesis. In this review article we will cover current knowledge of how plant CESA proteins synthesise cellulose. In particular the focus will be on the lessons learned from the recent work on the catalytic mechanism and the implications that new data on cellulose structure has for the assembly of CESA proteins into the large complex that synthesis plant cellulose microfibrils. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  17. Controlled Synthesis of Ultralong Carbon Nanotubes with Perfect Structures and Extraordinary Properties.

    PubMed

    Zhang, Rufan; Zhang, Yingying; Wei, Fei

    2017-02-21

    Carbon nanotubes (CNTs) have drawn intensive research interest in the past 25 years due to their excellent properties and wide applications. Ultralong CNTs refers to the horizontally aligned CNT arrays which are usually grown on flat substrates, parallel with each other with large intertube distances. They usually have perfect structures, excellent properties, and lengths up to centimeters, even decimeters. Ultralong CNTs are promising candidates as building blocks for transparent displays, nanoelectronics, superstrong tethers, aeronautics and aerospace materials, etc. The controlled synthesis of ultralong CNTs with perfect structures is the key to fully exploit the extraordinary properties of CNTs. CNTs are typical one-dimensional single-crystal nanomaterials. It has always been a great challenge how to grow macroscale single-crystals with no defects. Thus, the synthesis of ultralong CNTs with no defect is of significant importance from both fundamental and industrial aspects. In this Account, we focus on our progress on the controlled synthesis of ultralong CNTs with perfect structures and excellent properties. A deep understanding of the CNT growth mechanism is the first step for the controlled synthesis of ultralong CNTs with high quality. We first introduce the growth mechanism for ultralong CNTs and the main factor affecting their structures. We then discuss the strategies to control the defects in the as-grown ultralong CNTs. With these approaches, ultralong high-quality CNTs with different structures can be obtained. By completely eliminating the factors which may induce defects in the CNT walls, ultralong CNTs with perfect structures can be obtained. Their chiral indices keep unchanged for several centimeters long along the axial direction of the CNTs. The defect-free structures render the ultralong CNTs with excellent electrical, mechanical and thermal properties. The as-grown ultralong CNTs exhibit superhigh mechanical strength (>100 GPa) and their breaking strain (>17.5%) reach the theoretical limits. They also show excellent electrical and thermal properties. In addition, centimeters long CNTs showed macroscale interwall superlubricious properties due to their defect-free structures. Ultralong, defect-free CNTs with controlled structures are highly desirable for many high-end applications. We hope that this Account will shed light on the controlled synthesis of ultralong CNTs with perfect structures and excellent properties. Moreover, the growth mechanism and controlled synthesis of ultralong CNTs with perfect structures also offers a good model for other one-dimensional nanomaterials.

  18. Concepts in Biochemistry: Chemical Synthesis of DNA.

    ERIC Educational Resources Information Center

    Caruthers, Marvin H.

    1989-01-01

    Outlines the chemistry of the rapid synthesis of relatively large DNA fragments (100-200 monomers each) with yields exceeding 99 percent per coupling. DNA synthesis methodologies are outlined and a polymer-supported synthesis of DNA using deoxynucleoside phosphoramidites is described with structural formulas. (YP)

  19. Habitat Suitability Index Models: Beaver

    USGS Publications Warehouse

    Allen, Arthur W.

    1982-01-01

    Habitat preferences of the beaver (Castor canadensis) are described in this publication, which is one of a series of Habitat Suitability Index (HSI) models. Habitat use information is presented in a synthesis of the literature on the species-habitat requirements of the beaver, followed by the development of the HSI model. The model is designed to provide information for use in impact assessment and habitat management activities, and should be used in conjunction with habitat evaluation procedures previously developed by the Fish and Wildlife Service. This revised model updates the original publication dated September 1982.

  20. Concise synthesis and PTP1B inhibitory activity of (R)- and (S)-dihydroresorcylide.

    PubMed

    Jiang, Cheng-Shi; Zhang, Li; Gong, Jing-Xu; Li, Jing-Ya; Yao, Li-Gong; Li, Jia; Guo, Yue-Wei

    2017-12-01

    The present study was designed to develop a concise synthetic route for macrolide, with the purpose of confirming the absolute configuration of natural dihydroresorcylide (1) and making it more easily accessible for biological evaluation. The absolute configuration of C-3 in natural 1 was revised to be R by comparison of the rotation sign of synthetic (R)- and (S)-1. The synthetic (R)-1 was found to be a novel highly specific PTP1B inhibitor with an IC 50 value of 17.06 μM.

  1. Total synthesis of bryostatins: the development of methodology for the atom-economic and stereoselective synthesis of the ring C subunit.

    PubMed

    Trost, Barry M; Frontier, Alison J; Thiel, Oliver R; Yang, Hanbiao; Dong, Guangbin

    2011-08-22

    Bryostatins, a family of structurally complicated macrolides, exhibit an exceptional range of biological activities. The limited availability and structural complexity of these molecules makes development of an efficient total synthesis particularly important. This article describes our initial efforts towards the total synthesis of bryostatins, in which chemoselective and atom-economical methods for the stereoselective assembly of the ring C subunit were developed. A Pd-catalyzed tandem alkyne-alkyne coupling/6-endo-dig cyclization sequence was explored and successfully pursued in the synthesis of a dihydropyran ring system. Elaboration of this methodology ultimately led to a concise synthesis of the ring C subunit of bryostatins. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Approximation concepts for efficient structural synthesis

    NASA Technical Reports Server (NTRS)

    Schmit, L. A., Jr.; Miura, H.

    1976-01-01

    It is shown that efficient structural synthesis capabilities can be created by using approximation concepts to mesh finite element structural analysis methods with nonlinear mathematical programming techniques. The history of the application of mathematical programming techniques to structural design optimization problems is reviewed. Several rather general approximation concepts are described along with the technical foundations of the ACCESS 1 computer program, which implements several approximation concepts. A substantial collection of structural design problems involving truss and idealized wing structures is presented. It is concluded that since the basic ideas employed in creating the ACCESS 1 program are rather general, its successful development supports the contention that the introduction of approximation concepts will lead to the emergence of a new generation of practical and efficient, large scale, structural synthesis capabilities in which finite element analysis methods and mathematical programming algorithms will play a central role.

  3. Immunomodulatory constituents from an Ascomycete, Eupenicillium crustaceum, and revised absolute structure of macrophorin D.

    PubMed

    Fujimoto, H; Nakamura, E; Kim, Y P; Okuyama, E; Ishibashi, M; Sassa, T

    2001-09-01

    Fractionation guided by immunomodulatory activity of the EtOAc extract of the Ascomycete Eupenicillium crustaceum has afforded two new naturally occurring products, 4'-oxomacrophorin D (1) and 4'-oxomacrophorin A (2), as the immunosuppressive components of this fungus [1: 3-hydroxy-3-methylglutaryl (HMG) conjugate of 2]. The structures including the absolute configurations of 1 and 2 have been determined on the basis of chemical correlation of 1 with macrophorin D (3). The absolute configuration of the HMG moiety in 3 has been revised from 3R to 3S.

  4. The SAAS-R: A New Instrument to Assess the School Attitudes of Students with High and Low Academic Achievement in Spain

    ERIC Educational Resources Information Center

    Miñano Pérez, Pablo; Costa, Juan Luis Castejón; Corbi, Raquel Gilar; Iniesta, Alejandro Veas

    2017-01-01

    We examined the psychometric properties of the School Attitude Assessment Survey-Revised in a Spanish population (n = 1,398). Confirmatory factor analysis procedures supported the instrument's five-factor structure. The results of discriminant analysis demonstrated the predictive power of the School Attitude Assessment Survey-Revised scales as…

  5. 77 FR 29575 - Amendment to the International Traffic in Arms Regulations: Revision of U.S. Munitions List...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-18

    ... while the newly revised categories would follow a completely different numbering structure. In order to... under ECCN 0A617.e. Paragraph (c) is removed and placed in reserve; the articles currently controlled... opinion that this rule is exempt from the rulemaking provisions of 5 U.S.C. 553, it does not require...

  6. A revised econometric model of the domestic pallet market

    Treesearch

    Albert T. Schuler; Walter B. Wallin

    1983-01-01

    The purpose of this revised model is to project estimates of consumption and price of wooden pallets in the short term. This model differs from previous ones developed by Schuler and Wallin (1979 and 1980) in the following respects: The structure of the supply side of the market is more realistically identified (from an economic theory point of view) by including...

  7. Factor Structure and Psychometric Properties of the Revised Home Situations Questionnaire for Autism Spectrum Disorder: The Home Situations Questionnaire-Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Chowdhury, Monali; Aman, Michael G.; Lecavalier, Luc; Smith, Tristram; Johnson, Cynthia; Swiezy, Naomi; McCracken, James T.; King, Bryan; McDougle, Christopher J.; Bearss, Karen; Deng, Yanhong; Scahill, Lawrence

    2016-01-01

    Previously, we adapted the Home Situations Questionnaire to measure behavioral non-compliance in everyday settings in children with pervasive developmental disorders. In this study, we further revised this instrument for use in autism spectrum disorder and examined its psychometric properties (referred to as the Home Situations…

  8. Psychometric Validation of the Brief Adaptation to Disability Scale-Revised for Persons with Spinal Cord Injury in Taiwan

    ERIC Educational Resources Information Center

    Lin, Chen-Ping; Wang, Chia-Chiang; Fujikawa, Mayu; Brooks, Jessica; Eastvold-Walton, Lissa; Maxwell, Kristin; Chan, Fong

    2013-01-01

    Purpose: To examine the measurement structure of the Brief Adaptation to Disability Scale-Revised (B-ADS-R). Measure: A 12-item measure of disability acceptance based on the four value changes (enlarging the scope of values, containing the effects of the disability, subordinating the physique, and transforming comparative-status values to asset…

  9. Infusing Human Rights into the Curriculum: The Case of the South African Revised National Curriculum Statement

    ERIC Educational Resources Information Center

    Carrim, Nazir; Keet, Andre

    2005-01-01

    This article reflects on experiences of attempting to infuse human rights in the South African Revised National Curriculum Statement (RNCS). Using our experiences as members of Human Rights and Inclusivity Group (HRIWG), one of the curriculum development structures set up for the RNCS, and focusing particularly on the Learning Area of Mathematics,…

  10. Psychometric Properties of the School Attitude Assessment Survey-Revised with International Baccalaureate High School Students

    ERIC Educational Resources Information Center

    Dedrick, Robert F.; Shaunessy-Dedrick, Elizabeth; Suldo, Shannon M.; Ferron, John M.

    2015-01-01

    In two studies (ns = 312 and 1,149) with 9- to 12-grade students in pre-International Baccalaureate (IB) and IB Diploma programs, we evaluated the reliability, factor structure, measurement invariance, and criterion-related validity of the scores from the School Attitude Assessment Survey-Revised (SAAS-R). Reliabilities of the five SAAS-R subscale…

  11. The Latent Structure of Psychopathy: A Taxometric Investigation of the Psychopathy Checklist-Revised in a Heterogeneous Sample of Male Prison Inmates

    ERIC Educational Resources Information Center

    Walters, Glenn D.; Duncan, Scott A.; Mitchell-Perez, Kari

    2007-01-01

    A taxometric analysis of the Psychopathy Checklist-Revised (PCL-R) is conducted on a group of 409 male maximum-, medium-, and minimum-security federal prison inmates using the four PCL-R facet scores (interpersonal, affective, impulsive lifestyle, and antisocial behavior) as indicators. Results obtained from three quasi-independent taxometric…

  12. 75 FR 9756 - Airworthiness Directives; Bombardier, Inc. Model DHC-8-100 and DHC-8-200 Series Airplanes, and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-04

    ... defined in Part 1 of the Bombardier (de Havilland) DHC-6 Twin Otter, Dash 7 & Dash 8 Corrosion Prevention... Corrosion Prevention and Control Manual PSM 1-GEN- 5, Part 1, Revision 3, contains the revision level of... more likely to exhibit indications of corrosion. We are issuing this AD to prevent structural failure...

  13. Subject-Based and Cross-Curricular Approaches within the Revised Primary Curriculum in Northern Ireland: Teachers' Concerns and Preferred Approaches

    ERIC Educational Resources Information Center

    Greenwood, Richard

    2013-01-01

    A revision of the Northern Ireland Primary Curriculum took place in 2007. It promotes strongly a cross-curricular or thematic approach to planning and teaching and has an "Area of Learning" structure which includes geography alongside history and science and technology in an area called "The World Around Us". Responses from…

  14. 76 FR 69292 - Aging Management of Stainless Steel Structures and Components in Treated Borated Water

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-08

    ... NUCLEAR REGULATORY COMMISSION [NRC-2011-0256] Aging Management of Stainless Steel Structures and... Stainless Steel Structures and Components in Treated Borated Water.'' This LR-ISG revises the guidance in...) and Generic Aging Lessons Learned (GALL) Report for the aging management of stainless steel structures...

  15. 75 FR 68809 - Agency Information Collection Activities: Importation Bond Structure

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-09

    ... Activities: Importation Bond Structure AGENCY: U.S. Customs and Border Protection, Department of Homeland... Structure. This is a proposed extension and revision of an information collection that was previously...: Importation Bond Structure. OMB Number: 1651-0050. Form Numbers: 301 and 5297. Abstract: Bonds are used to...

  16. 77 FR 74883 - Aging Management of Stainless Steel Structures and Components in Treated Borated Water; Revision 1

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-18

    ... NUCLEAR REGULATORY COMMISSION [NRC-2011-0256] Aging Management of Stainless Steel Structures and..., ``Aging Management of Stainless Steel Structures and Components in Treated Borated Water,'' which was... Staff Guidance LR-ISG-2011-01, ``Aging Management of Stainless Steel Structures and Components in...

  17. Convergent Synthesis and Structural Confirmation of Phellodonin and Sarcodonin ε

    PubMed Central

    Usui, Ippei; Lin, David W.; Masuda, Takeshi

    2013-01-01

    The first synthesis of members of the sarcodonin family, phellodonin and sarcodonin ε, is reported herein. This verifies that the unprecedented and seemingly unstable N,N-dioxide-containing benzodioxazine framework can be constructed in the laboratory, and lends further support to the proposed structures. The key step in the synthesis involves a biomimetic hetero-Diels–Alder reaction between a pyrazine N-oxide and an ortho-quinone. PMID:23577748

  18. Chemistry of Peptidoglycan in Mycobacterium tuberculosis Life Cycle: An off-the-wall Balance of Synthesis and Degradation.

    PubMed

    Squeglia, Flavia; Ruggiero, Alessia; Berisio, Rita

    2018-02-21

    The cell wall envelope of mycobacteria is structurally distinct from that of both Gram-positive and Gram-negative bacteria. In Mycobacterium tuberculosis, this cell wall has unique structural features and plays a crucial role in drug resistance and macrophage survival under stress conditions. Peptidoglycan is the major constituent of this cell wall, with an important structural role, giving structural strength, and counteracting the osmotic pressure of the cytoplasm. Synthesis of this complex polymer takes place in three stages that occur at three different locations in the cell, from the cytoplasm to the external side of the cell membrane, where polymerization occurs. A fine balance of peptidoglycan synthesis and degradation is responsible for a plethora of molecular mechanisms which are key to the pathogenicity of M. tuberculosis. Enlargement of mycobacterial cells can occur through the synthesis of new peptidoglycan, autolysis of old peptidoglycan, or a combination of both processes. Here, we discuss the chemical aspects of peptidoglycan synthesis and degradation, in relation to metabolic stages of M. tuberculosis. Going from inside the mycobacterial cytoplasm to outside its membrane, we describe the assembly line of peptidoglycan synthesis and polymerization, and continue with its depolymerization events and their consequences on mycobacterial life and resuscitation from dormancy. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Studies of Xenopus laevis mitochondrial DNA: D-loop mapping and characterization of DNA-binding proteins

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cairns, S.S.

    1987-01-01

    In X. laevis oocytes, mitochondrial DNA accumulates to 10/sup 5/ times the somatic cell complement, and is characterized by a high frequency of a triple-stranded displacement hoop structure at the origin of replication. To map the termini of the single strands, it was necessary to correct the nucleotide sequence of the D-loop region. The revised sequence of 2458 nucleotides contains 54 discrepancies in comparison to a previously published sequence. Radiolabeling of the nascent strands of the D-loop structure either at the 5' end or at the 3' end identifies a major species with a length of 1670 nucleotides. Cleavage ofmore » the 5' labeled strands reveals two families of ends located near several matches to an element, designated CSB-1, that is conserved in this location in several vertebrate genomes. Cleavage of 3' labeled strands produced one fragment. The unique 3' end maps to about 15 nucleotides preceding the tRNA/sup Pro/ gene. A search for proteins which may bind to mtDNA in this region to regulate nucleic acid synthesis has identified three activities in lysates of X. laevis mitochondria. The DNA-binding proteins were assayed by monitoring their ability to retard the migration of labeled double- or single-stranded DNA fragments in polyacrylamide gels. The DNA binding preference was determined by competition with an excess of either ds- or ssDNA.« less

  20. Experimental Research on the Dense CFB's Riser and the Simulation Based on the EMMS Model

    NASA Astrophysics Data System (ADS)

    Wang, X. Y.; Wang, S. D.; Fan, B. G.; Liao, L. L.; Jiang, F.; Xu, X.; Wu, X. Z.; Xiao, Y. H.

    2010-03-01

    The flow structure in the CFB (circulating fluidized bed) riser has been investigated. Experimental studies were performed in a cold square section unit with 270 mm×270 mm×10 m. Since the drag force model based on homogeneous two-phase flow such as the Gidaspow drag model could not depict the heterogeneous structures of the gas-solid flow, the structure-dependent energy-minimization multi-scale (EMMS) model based on the heterogenerity was applied in the paper and a revised drag force model based on the EMMS model was proposed. A 2D two-fluid model was used to simulate a bench-scale square cross-section riser of a cold CFB. The typical core-annulus structure and the back-mixing near the wall of the riser were observed and the assembly and fragmentation processes of clusters were captured. By comparing with the Gidaspow drag model, the results obtained by the revised drag model based on EMMS shows better consistency with the experimental data. The model can also depict the difference from the two exit configurations. This study once again proves the key role of drag force in CFD (Computational Fluid Dynamics) simulation and also shows the availability of the revised drag model to describe the gas-solid flow in CFB risers.

  1. Influence of Synthesis Mode of Supplement Based on Calcium Hydrosylicates on the Structure and Properties of Lime Compositions

    NASA Astrophysics Data System (ADS)

    Loganina, V. I.; Pyshkina, I. S.

    2017-11-01

    It was proposed to use synthesized calcium hydrosilicates in finishing lime dry mixes as a modifying supplement. The effect of substances containing amorphous silica which are used for synthesis on the activity of the modifying supplement was established. The effect of the synthesis mode of supplement on the structure formation of lime compositions was illustrated. It was found that the injection of supplements of hydrosilicates accelerates the increase of mechanical strength. The efficiency of the modifying supplements of amorphous silica, such as diatomite, in the synthesis was shown.

  2. Stereoselective heterocycle synthesis through oxidative carbon-hydrogen bond activation.

    PubMed

    Liu, Lei; Floreancig, Paul E

    2010-01-01

    Heterocycles are ubiquitous structures in both drugs and natural products, and efficient methods for their construction are being pursued constantly. Carbon-hydrogen bond activation offers numerous advantages for the synthesis of heterocycles with respect to minimizing the length of synthetic routes and reducing waste. As interest in chiral medicinal leads increases, stereoselective methods for heterocycle synthesis must be developed. The use of carbon-hydrogen bond activation reactions for stereoselective heterocycle synthesis has produced a range of creative transformations that provide a wide array of structural motifs, selected examples of which are described in this review.

  3. Kinematical synthesis of an inversion of the double linked fourbar for morphing wing applications

    NASA Astrophysics Data System (ADS)

    Aguirrebeitia, J.; Avilés, R.; Fernández, I.; Abasolo, M.

    2013-03-01

    This paper presents the kinematical features of an inversion of the double linked fourbar for morphing wing purposes. The structure of the mechanism is obtained using structural synthesis concepts, from an initial conceptual schematic. Then, kinematic characteristics as instant center of rotation, lock positions, dead point positions and uncertainty positions are derived for this mechanism in order to face the last step, the dimensional synthesis; in this sense, two kinds of dimensional synthesis are arranged to guide the wing along two positions, and to fulfill with the second one some aerodynamic and minimum actuation energy related issues.

  4. An improved divergent synthesis of comb-type branched oligodeoxyribonucleotides (bDNA) containing multiple secondary sequences.

    PubMed

    Horn, T; Chang, C A; Urdea, M S

    1997-12-01

    The divergent synthesis of branched DNA (bDNA) comb structures is described. This new type of bDNA contains one unique oligonucleotide, the primary sequence, covalently attached through a comb-like branch network to many identical copies of a different oligonucleotide, the secondary sequence. The bDNA comb structures were assembled on a solid support and several synthesis parameters were investigated and optimized. The bDNA comb molecules were characterized by polyacrylamide gel electrophoretic methods and by controlled cleavage at periodate-cleavable moieties incorporated during synthesis. The developed chemistry allows synthesis of bDNA comb molecules containing multiple secondary sequences. In the accompanying article we describe the synthesis and characterization of large bDNA combs containing all four deoxynucleotides for use as signal amplifiers in nucleic acid quantification assays.

  5. An improved divergent synthesis of comb-type branched oligodeoxyribonucleotides (bDNA) containing multiple secondary sequences.

    PubMed Central

    Horn, T; Chang, C A; Urdea, M S

    1997-01-01

    The divergent synthesis of branched DNA (bDNA) comb structures is described. This new type of bDNA contains one unique oligonucleotide, the primary sequence, covalently attached through a comb-like branch network to many identical copies of a different oligonucleotide, the secondary sequence. The bDNA comb structures were assembled on a solid support and several synthesis parameters were investigated and optimized. The bDNA comb molecules were characterized by polyacrylamide gel electrophoretic methods and by controlled cleavage at periodate-cleavable moieties incorporated during synthesis. The developed chemistry allows synthesis of bDNA comb molecules containing multiple secondary sequences. In the accompanying article we describe the synthesis and characterization of large bDNA combs containing all four deoxynucleotides for use as signal amplifiers in nucleic acid quantification assays. PMID:9365265

  6. An Investigation of Porous Structure of TiNi-Based SHS-Materials Produced at Different Initial Synthesis Temperatures

    NASA Astrophysics Data System (ADS)

    Khodorenko, V. N.; Anikeev, S. G.; Kokorev, O. V.; Yasenchuk, Yu. F.; Gunther, V. É.

    2018-02-01

    An investigation of structural characteristics and behavior of TiNi-based pore-permeable materials manufactured by the methods of selfpropagating high-temperature synthesis (SHS) at the initial synthesis temperatures T = 400 and 600°C is performed. It is shown that depending on the temperature regime, the resulting structure and properties of the material can differ. It is found out that the SHS-material produced at the initial synthesis temperature T = 400°C possesses the largest number of micropores in the pore wall surface structure due to a high phase inhomogeneity of the alloy. The regime of structure optimization of the resulting materials is described and the main stages of formation of the pore wall microporous surfaces are revealed. It is demonstrated that after optimization of the surface structure of a TiNi-based fine-pore alloy by its chemical etching, the fraction of micropores measuring in size less than 50 nm increased from 59 to 68%, while the number of pores larger than 1 μm increased twofold from 11 to 22%. In addition, peculiar features of interaction between certain cell cultures with the surface of the SHS-material manufactured at different initial synthesis temperatures are revealed. It is found out that the dynamics of the cell material integration depends on the pore wall surface morphology and dimensions of macropores.

  7. Component mode synthesis and large deflection vibrations of complex structures. [beams and trusses

    NASA Technical Reports Server (NTRS)

    Mei, C.

    1984-01-01

    The accuracy of the NASTRAN modal synthesis analysis was assessed by comparing it with full structure NASTRAN and nine other modal synthesis results using a nine-bay truss. A NASTRAN component mode transient response analysis was also performed on the free-free truss structure. A finite element method was developed for nonlinear vibration of beam structures subjected to harmonic excitation. Longitudinal deformation and inertia are both included in the formula. Tables show the finite element free vibration results with and without considering the effects of longitudinal deformation and inertia as well as the frequency ratios for a simply supported and a clamped beam subjected to a uniform harmonic force.

  8. Time Dependent Structural Evolution of Porous Organic Cage CC3

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lucero, Jolie; Elsaidi, Sameh; Anderson, Ryther

    Porous organic cage compounds are emerged with remarkable structural diversity and functionality that have applications in gas separation, catalysis and energy storage. Fundamental understanding of nucleation and growth of such materials have significant implications for understanding molecularly directed self-assembly phenomena. Herein we followed the structural evolution of a prototypical type of porous organic cage, CC3 as a function of synthesis time. Three distinctive crystal formation stages were identified: at short synthesis times, a rapid crystal growth stage in which amorphous agglomerates transformed into larger irregular particles was observed. At intermediate synthesis times, a decrease in crystal size over time wasmore » observed presumably due to crystal fragmentation, redissolution and/or homogeneous nucleation led. Finally, at longer synthesis times, a regrowth process was observed in which particles coalesced through Ostwald ripening leading to a continuous increase in crystal size. Molecular simulation studies, based on the construction of in silico CC3 models and simulation of XRD patterns and nitrogen isotherms, confirm the samples at different synthesis times to be a mixture of CC3α and CC3 amorphous phases. The CC3α phase is found to contract at different synthesis times, and the amorphous phase is found to essentially disappear at the longest synthesis time. Nitrogen and carbon dioxide adsorption properties of these CC3 phases were evaluated, and were highly dependent on synthesis time.« less

  9. Synthesis and structural study of N-isopropenylbenzimidazolone

    NASA Astrophysics Data System (ADS)

    Mondieig, D.; Negrier, Ph.; Leger, J. M.; Lakhrissi, L.; El Assyry, A.; Lakhrissi, B.; Essassi, E. M.; Benali, B.; Boucetta, A.

    2015-05-01

    The synthesis and the crystal structure of the N-isopropenylbenzimidazolone (C10H10N2O) are presented. The synthesis was performed by Meth-Cohen method by reaction of o-phenylenediamine with ethyl acetoacetate in refluxed xylene. The single crystal structure was determined at room temperature by means of X-rays diffraction. The crystal system is monoclinic, with space group C2/c and eight molecules per unit cell. The unit cell dimensions are: a = 15.978(1) Å, b = 6.100(2) Å, c = 18.222(2) Å, β = 90.16(1)° and V = 1776.0(6) Å3.

  10. Robust control synthesis for uncertain dynamical systems

    NASA Technical Reports Server (NTRS)

    Byun, Kuk-Whan; Wie, Bong; Sunkel, John

    1989-01-01

    This paper presents robust control synthesis techniques for uncertain dynamical systems subject to structured parameter perturbation. Both QFT (quantitative feedback theory) and H-infinity control synthesis techniques are investigated. Although most H-infinity-related control techniques are not concerned with the structured parameter perturbation, a new way of incorporating the parameter uncertainty in the robust H-infinity control design is presented. A generic model of uncertain dynamical systems is used to illustrate the design methodologies investigated in this paper. It is shown that, for a certain noncolocated structural control problem, use of both techniques results in nonminimum phase compensation.

  11. 78 FR 11572 - Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-19

    ... Revision No. 04-03, dated October 15, 2012, which transmits Unclassified 12-A/AMP-04 ``STRUCTURAL... October 15, 2012, which transmits Unclassified 12-B/AMP-04 ``STRUCTURAL AND COMPONENT LIMITATIONS... Unclassified 12-A/AMP-04 ``STRUCTURAL, COMPONENT AND MISCELLANEOUS--AIRWORTHINESS LIMITATIONS,'' document 12-A...

  12. Structural Revisions of a Class of Natural Products: Scaffolds of Aglycon Analogues of Fusicoccins and Cotylenins Isolated from Fungi.

    PubMed

    Tang, Ying; Xue, Yongbo; Du, Guang; Wang, Jianping; Liu, Junjun; Sun, Bin; Li, Xiao-Nian; Yao, Guangmin; Luo, Zengwei; Zhang, Yonghui

    2016-03-14

    The reisolation and structural revision of brassicicene D is described, and inspired us to reassign the core skeletons of brassicicenes C-H, J and K, ranging from dicyclopenta[a,d]cyclooctane to tricyclo[9.2.1.0(3,7)]tetradecane using quantum-chemical predictions and experimental validation strategies. Three novel, highly modified fusicoccanes, brassicicenes L-N, were also isolated from the fungus Alternaria brassicicola, and their structures were unequivocally established by spectroscopic data, ECD calculations, and crystallography. The reassigned structures represent the first class of bridgehead double-bond-containing natural products with a bicyclo[6.2.1]undecane carbon skeleton. Furthermore, their stabilities were first predicted with olefin strain energy calculations. Collectively, these findings extend our view of the application of computational predictions and biosynthetic logic-based structure elucidation to address problems related to the structure and stability of natural products. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Perfectionism among Chinese Gifted and Nongifted Students in Hong Kong: The Use of the Revised Almost Perfect Scale

    ERIC Educational Resources Information Center

    Chan, David W.

    2011-01-01

    This study investigated the structure of perfectionism based on the almost Perfect Scale-Revised with a sample of 320 gifted students aged 7 to 12 and a sample of 882 nongifted students of similar ages in Hong Kong. Multigroup confirmatory factor analyses across the two student groups supported a common three-dimensional model that included…

  14. Energetics of Amino Acid Synthesis in Alkaline Hydrothermal Environments

    NASA Astrophysics Data System (ADS)

    Kitadai, Norio

    2015-12-01

    Alkaline hydrothermal systems have received considerable attention as candidates for the origin and evolution of life on the primitive Earth. Nevertheless, sufficient information has not yet been obtained for the thermodynamic properties of amino acids, which are necessary components for life, at high temperatures and alkaline pH. These properties were estimated using experimental high-temperature volume and heat capacity data reported in the literature for several amino acids, together with correlation algorithms and the revised Helgeson-Kirkham-Flowers (HKF) equations of state. This approach enabled determination of a complete set of the standard molal thermodynamic data and the revised HKF parameters for the 20 protein amino acids in their zwitterionic and ionization states. The obtained dataset was then used to evaluate the energetics of amino acid syntheses from simple inorganic precursors (CO2, H2, NH3 and H2S) in a simulated alkaline hydrothermal system on the Hadean Earth. Results show that mixing between CO2-rich seawater and the H2-rich hydrothermal fluid can produce energetically favorable conditions for amino acid syntheses, particularly in the lower-temperature region of such systems. Together with data related to the pH and temperature dependences of the energetics of amino acid polymerizations presented in earlier reports, these results suggest the following. Hadean alkaline hydrothermal settings, where steep pH and temperature gradients may have existed between cool, slightly acidic Hadean ocean water and hot, alkaline hydrothermal fluids at the vent-ocean interface, may be energetically the most suitable environment for the synthesis and polymerization of amino acids.

  15. Energetics of Amino Acid Synthesis in Alkaline Hydrothermal Environments.

    PubMed

    Kitadai, Norio

    2015-12-01

    Alkaline hydrothermal systems have received considerable attention as candidates for the origin and evolution of life on the primitive Earth. Nevertheless, sufficient information has not yet been obtained for the thermodynamic properties of amino acids, which are necessary components for life, at high temperatures and alkaline pH. These properties were estimated using experimental high-temperature volume and heat capacity data reported in the literature for several amino acids, together with correlation algorithms and the revised Helgeson-Kirkham-Flowers (HKF) equations of state. This approach enabled determination of a complete set of the standard molal thermodynamic data and the revised HKF parameters for the 20 protein amino acids in their zwitterionic and ionization states. The obtained dataset was then used to evaluate the energetics of amino acid syntheses from simple inorganic precursors (CO2, H2, NH3 and H2S) in a simulated alkaline hydrothermal system on the Hadean Earth. Results show that mixing between CO2-rich seawater and the H2-rich hydrothermal fluid can produce energetically favorable conditions for amino acid syntheses, particularly in the lower-temperature region of such systems. Together with data related to the pH and temperature dependences of the energetics of amino acid polymerizations presented in earlier reports, these results suggest the following. Hadean alkaline hydrothermal settings, where steep pH and temperature gradients may have existed between cool, slightly acidic Hadean ocean water and hot, alkaline hydrothermal fluids at the vent-ocean interface, may be energetically the most suitable environment for the synthesis and polymerization of amino acids.

  16. Guidance on the Technology Performance Level (TPL) Assessment Methodology

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Weber, Jochem; Roberts, Jesse D.; Babarit, Aurelien

    This document presents the revised Technology Performance Level (TPL) assessment methodology. There are three parts to this revised methodology 1) the Stakeholder Needs and Assessment Guidance (this document), 2) the Technical Submission form, 3) the TPL scoring spreadsheet. The TPL assessment is designed to give a technology neutral or agnostic assessment of any wave energy converter technology. The focus of the TPL is on the performance of the technology in meeting the customer’s needs. The original TPL is described in [1, 2] and those references also detail the critical differences in the nature of the TPL when compared to themore » more widely used technology readiness level (TRL). (Wave energy TRL is described in [3]). The revised TPL is particularly intended to be useful to investors and also to assist technology developers to conduct comprehensive assessments in a way that is meaningful and attractive to investors. The revised TPL assessment methodology has been derived through a structured Systems Engineering approach. This was a formal process which involved analyzing customer and stakeholder needs through the discipline of Systems Engineering. The results of the process confirmed the high level of completeness of the original methodology presented in [1] (as used in the Wave Energy Prize judging) and now add a significantly increased level of detail in the assessment and an improved more investment focused structure. The revised TPL also incorporates the feedback of the Wave Energy Prize judges.« less

  17. Design of overhead VMS structures for fatigue loads.

    DOT National Transportation Integrated Search

    2011-07-31

    The 2001 edition of the American Association of State Highway and Transportation Officials (AASHTO) : Standard Specifications for Structural Supports for Highway Signs, Luminaires and Traffic Signals has been : revised in its entirety through a major...

  18. A redefinition of the representation of mammary cells and enzyme activities in a lactating dairy cow model.

    PubMed

    Hanigan, M D; Rius, A G; Kolver, E S; Palliser, C C

    2007-08-01

    The Molly model predicts various aspects of digestion and metabolism in the cow, including nutrient partitioning between milk and body stores. It has been observed previously that the model underpredicts milk component yield responses to nutrition and consequently overpredicts body energy store responses. In Molly, mammary enzyme activity is represented as an aggregate of mammary cell numbers and activity per cell with minimal endocrine regulation. Work by others suggests that mammary cells can cycle between active and quiescent states in response to various stimuli. Simple models of milk production have demonstrated the utility of this representation when using the model to simulate variable milking and nutrient restriction. It was hypothesized that replacing the current representation of mammary cells and enzyme activity in Molly with a representation of active and quiescent cells and improving the representation of endocrine control of cell activity would improve predictions of milk component yield. The static representation of cell numbers was replaced with a representation of cell growth during gestation and early lactation periods and first-order cell death. Enzyme capacity for fat and protein synthesis was assumed to be proportional to cell numbers. Enzyme capacity for lactose synthesis was represented with the same equation form as for cell numbers. Data used for parameter estimation were collected as part of an extended lactation trial. Cows with North American or New Zealand genotypes were fed 0, 3, or 6 kg of concentrate dry matter daily during a 600-d lactation. The original model had root mean square prediction errors of 17.7, 22.3, and 19.8% for lactose, protein, and fat yield, respectively, as compared with values of 8.3, 9.4, and 11.7% for the revised model, respectively. The original model predicted body weight with an error of 19.7% vs. 5.7% for the revised model. Based on these observations, it was concluded that representing mammary synthetic capacity as a function of active cell numbers and revisions to endocrine control of cell activity was meritorious.

  19. An Innovative Electrolysis Approach for the Synthesis of Metal Matrix Bulk Nanocomposites: A Case Study on Copper-Niobium System

    NASA Astrophysics Data System (ADS)

    Shokrvash, Hussein; Rad, Rahim Yazdani; Massoudi, Abouzar

    2018-04-01

    Design and synthesis of a prototype Cu-Nb nanocomposite are presented. Oxygen-free Cu-Nb nanocomposites were prepared using an electrolysis facility with special emphasis on the cathodic deoxidation of Cu and nanometric Nb2O5 blends in a molten NaCl-CaCl2 electrolyte. The as-prepared nanocomposites were characterized by X-ray diffraction and energy-dispersive X-ray spectroscopy. The elemental analysis of the Cu matrix and Nb phase revealed the high solubility of Nb in the Cu structure (0.85 at. pct) and Cu in the Nb structure (10.59 at. pct) over short synthesis times (4-5 hours). Furthermore, precise analysis using field emission scanning electron microscopy and transmission electron microscopy confirmed the unique structure and nanocomposite morphology of the Cu-Nb nanocomposite. The successful synthesis of Cu-Nb nanocomposites offers a new conceptual and empirical outlook on the generation of bulk nanostructures of immiscible bimetals using electro-synthesis.

  20. Divergent Synthesis of Heparan Sulfate Oligosaccharides

    PubMed Central

    2015-01-01

    Heparan sulfates are implicated in a wide range of biological processes. A major challenge in deciphering their structure and activity relationship is the synthetic difficulties to access diverse heparan sulfate oligosaccharides with well-defined sulfation patterns. In order to expedite the synthesis, a divergent synthetic strategy was developed. By integrating chemical synthesis and two types of O-sulfo transferases, seven different hexasaccharides were obtained from a single hexasaccharide precursor. This approach combined the flexibility of chemical synthesis with the selectivity of enzyme-catalyzed sulfations, thus simplifying the overall synthetic operations. In an attempt to establish structure activity relationships of heparan sulfate binding with its receptor, the synthesized oligosaccharides were incorporated onto a glycan microarray, and their bindings with a growth factor FGF-2 were examined. The unique combination of chemical and enzymatic approaches expanded the capability of oligosaccharide synthesis. In addition, the well-defined heparan sulfate structures helped shine light on the fine substrate specificities of biosynthetic enzymes and confirm the potential sequence of enzymatic reactions in biosynthesis. PMID:26574650

  1. A new look at Togo through the eyes of a SLAR

    NASA Technical Reports Server (NTRS)

    Dellwig, L. F.

    1980-01-01

    Imaging of Togo in 1977 with SLAR provided the data required for the production of map controlled radar mosaics at a scale of 1:200,000 with 95 percent of all control points at that scale within + or - 4.0 millimeters of true positions. The moasics served as the base for the generation of a revised geologic map of Togo. Aided by two looks, numerous revisions resulted, not only with the addition of previously unknown structural features, a revision of age relationships, and the refinement of unit boundaries, but also with the repositioning of rock units and the reorientation of major faults.

  2. Recent Developments in Transformational Grammar.

    ERIC Educational Resources Information Center

    Jacobs, Roderick A.

    1969-01-01

    In the years following the appearance of Noam Chomsky's book, "Syntactic Structures," in 1957, transformational grammarians modified and improved his initial model of language. The notion of a deep structure of meaning underlying a sentence's surface structure was revised to embody elements representing negation, command, and interrogation, and to…

  3. The structure of social exchange in self-help support groups: development of a measure.

    PubMed

    Brown, Louis D; Tang, Xiaohui; Hollman, Ruth L

    2014-03-01

    Self-help support groups are indigenous community resources designed to help people manage a variety of personal challenges, from alcohol abuse to xeroderma pigmentosum. The social exchanges that occur during group meetings are central to understanding how people benefit from participation. This paper examines the different types of social exchange behaviors that occur during meetings, using two studies to develop empirically distinct scales that reliably measure theoretically important types of exchange. Resource theory informed the initial measurement development efforts. Exploratory factor analyses from the first study led to revisions in the factor structure of the social exchange scales. The revised measure captured the exchange of emotional support, experiential information, humor, unwanted behaviors, and exchanges outside meetings. Confirmatory factor analyses from a follow-up study with a different sample of self-help support groups provided good model fit, suggesting the revised structure accurately represented the data. Further, the scales demonstrated good convergent and discriminant validity with related constructs. Future research can use the scales to identify aspects of social exchange that are most important in improving health outcomes among self-help support group participants. Groups can use the scales in practice to celebrate strengths and address weaknesses in their social exchange dynamics.

  4. Synthesis of 1-O-methylchlorogenic acid: reassignment of structure for MCGA3 isolated from bamboo (Phyllostachys edulis) leaves

    USDA-ARS?s Scientific Manuscript database

    The first synthesis of 1-O-methylchlorogenic acid is described. The short and efficient synthesis of this compound provides laboratory-scale quantities of the material to investigate its biological properties. The synthesis involved C-1 alkylation of the known (-)-4,5-cyclohexylidenequinic acid lact...

  5. Synthesis of Large-Area 2D Layered Materials and Their Heterostacking Structures

    DTIC Science & Technology

    2017-10-13

    Volume: 6 Pages: 7666 Published: JUL 2015 4. Title: Atomically Thin Heterostructures Based on Single- Layer Tungsten Diselenide and DISTRIBUTION A...AFRL-AFOSR-JP-TR-2017-0070 Synthesis of Large-Area 2D layered Materials and Their Heterostacking Structures Chih-Wei Chu Academia Sinica Final Report...TYPE Final 3. DATES COVERED (From - To) 20 Nov 2014 to 19 Nov 2016 4. TITLE AND SUBTITLE Synthesis of Large-Area 2D layered Materials and Their

  6. Stereoselective Total Synthesis of (±)-5- epi-Cyanthiwigin I via an Intramolecular Pauson-Khand Reaction as the Key Step.

    PubMed

    Chang, Yuanyuan; Shi, Linlin; Huang, Jun; Shi, Lili; Zhang, Zichun; Hao, Hong-Dong; Gong, Jianxian; Yang, Zhen

    2018-05-09

    A convenient approach to the construction of the 5-6-7 tricarbocyclic fused core structure of cyanthiwigins via a Co-mediated Pauson-Khand reaction as a key step has been developed. The cyathane core intermediate obtained by this strategy was used in the concise synthesis of (±)-5- epi-cyanthiwigin I. The developed chemistry paves the way for the total synthesis of structurally diverse cyanthiwigins.

  7. Synthesis, Characterization, and Secondary Structure Determination of a Silk-Inspired, Self-Assembling Peptide: A Laboratory Exercise for Organic and Biochemistry Courses

    ERIC Educational Resources Information Center

    Albin, Tyler J.; Fry, Melany M.; Murphy, Amanda R.

    2014-01-01

    This laboratory experiment gives upper-division organic or biochemistry undergraduate students a comprehensive look at the synthesis, chemical characterization, self-assembly, and secondary structure determination of small, N-acylated peptides inspired by the protein structure of silkworm silk. All experiments can be completed in one 4 h lab…

  8. Effects of Gold Salt Speciation and Structure of Human and Bovine Serum Albumins on the Synthesis and Stability of Gold Nanostructures

    PubMed Central

    Miranda, Érica G. A.; Tofanello, Aryane; Brito, Adrianne M. M.; Lopes, David M.; Albuquerque, Lindomar J. C.; de Castro, Carlos E.; Costa, Fanny N.; Giacomelli, Fernando C.; Ferreira, Fabio F.; Araújo-Chaves, Juliana C.; Nantes, Iseli L.

    2016-01-01

    The present study aimed to investigate the influence of albumin structure and gold speciation on the synthesis of gold nanoparticles (GNPs). The strategy of synthesis was the addition of HAuCl4 solutions at different pH values (3–12) to solutions of human and bovine serum albumins (HSA and BSA) at the same corresponding pH values. Different pH values influence the GNP synthesis due to gold speciation. Besides the inherent effect of pH on the native structure of albumins, the use N-ethylmaleimide (NEM)-treated and heat-denaturated forms of HSA and BSA provided additional insights about the influence of protein structure, net charge, and thiol group approachability on the GNP synthesis. NEM treatment, heating, and the extreme values of pH promoted loss of the native albumin structure. The formation of GNPs indicated by the appearance of surface plasmon resonance (SPR) bands became detectable from 15 days of the synthesis processes that were carried out with native, NEM-treated and heat-denaturated forms of HSA and BSA, exclusively at pH 6 and 7. After 2 months of incubation, SPR band was also detected for all synthesis carried out at pH 8.0. The mean values of the hydrodynamic radius (RH) were 24 and 34 nm for GNPs synthesized with native HSA and BSA, respectively. X-ray diffraction (XRD) revealed crystallites of 13 nm. RH, XRD, and zeta potential values were consistent with GNP capping by the albumins. However, the GNPs produced with NEM-treated and heat-denaturated albumins exhibited loss of protein capping by lowering the ionic strength. This result suggests a significant contribution of non-electrostatic interactions of albumins with the GNP surface, in these conditions. The denaturation of proteins exposes hydrophobic groups to the solvent, and these groups could interact with the gold surface. In these conditions, the thiol blockage or oxidation, the latter probably favored upon heating, impaired the formation of a stable capping by thiol coordination with the gold surface. Therefore, the cysteine side chain of albumins is important for the colloidal stabilization of GNPs rather than as the reducing agent for the synthesis. Despite the presence of more reactive gold species at more acidic pH values, i.e., below 6.0, in these conditions the loss of native albumin structure impaired GNP synthesis. Alkaline pH values (9–12) combined the unfavorable conditions of denaturated protein structure with less reactive gold species. Therefore, an optimal condition for the synthesis of GNPs using serum albumins involves more reactive gold salt species combined with a reducing and negatively charged form of the protein, all favored at pH 6–7. PMID:27066476

  9. Processing of laser formed SiC powder

    NASA Technical Reports Server (NTRS)

    Haggerty, J. S.; Bowen, H. K.

    1985-01-01

    Superior SiC characteristics can be achieved through the use of ideal constituent powders and careful post-synthesis processing steps. High purity SiC powders of approx. 1000 A uniform diameter, nonagglomerated and spherical were produced. This required major revision of the particle formation and growth model from one based on classical nucleation and growth to one based on collision and coalescence of Si particles followed by their carburization. Dispersions based on pure organic solvents as well as steric stabilization were investigated. Although stable dispersions were formed by both, subsequent part fabrication emphasized the pure solvents since fewer problems with drying and residuals of the high purity particles were anticipated. Test parts were made by the colloidal pressing technique; both liquid filtration and consolidation (rearrangement) stages were modeled. Green densities corresponding to a random close packed structure (approx. 63%) were achieved; this highly perfect structure has a high, uniform coordination number (greater than 11) approaching the quality of an ordered structure without introducing domain boundary effects. After drying, parts were densified at temperatures ranging from 1800 to 2100 C. Optimum densification temperatures will probably be in the 1900 to 2000 C range based on these preliminary results which showed that 2050 C samples had experienced substantial grain growth. Although overfired, the 2050 C samples exhibited excellent mechanical properties. Biaxial tensile strengths up to 714 MPa and Vickers hardness values of 2430 kg/sq mm 2 were both more typical of hot pressed than sintered SiC. Both result from the absence of large defects and the confinement of residual porosity (less than 2.5%) to small diameter, uniformly distributed pores.

  10. Integrated Science Assessment (ISA) for Carbon Monoxide ...

    EPA Pesticide Factsheets

    EPA announced that the Second External Review Draft of the Integrated Science Assessment (ISA) for Carbon Monoxide (CO) and related Annexes was made available for independent peer review and public review. This draft ISA document represents a concise synthesis and evaluation of the most policy-relevant science and will ultimately provide the scientific bases for EPA's decision regarding whether the current standards for CO sufficiently protect public health and the environment. Section 108(a) of the Clean Air Act directs the EPA Administrator to identify certain pollutants that “cause or contribute to air pollution which may reasonably be anticipated to endanger public health or welfare” and to issue air quality criteria for them. These air quality criteria are to “accurately reflect the latest scientific knowledge useful in indicating the kind and extent of all identifiable effects on public health or welfare which may be expected from the presence of such pollutant in the ambient air….” Under section 109 of the Act, EPA is to establish national ambient air quality standards (NAAQS) for each pollutant for which EPA has issued criteria. Section 109(d) of the Act requires periodic review and, if appropriate, revision of existing air quality criteria to reflect advances in scientific knowledge on the effects of the pollutant on public health or welfare. EPA is also to revise the NAAQS, if appropriate, based on the revised air quality criteria.

  11. Integrated Science Assessment (ISA) for Oxides of Nitrogen ...

    EPA Pesticide Factsheets

    EPA is announcing the availability of the First External Review Draft of the Integrated Science Assessment for Oxides of Nitrogen – Health Criteria for public comment and independent peer review. This draft document provides EPA’s evaluation and synthesis of the most policy-relevant science related to the health effects of oxides of nitrogen. When final, it will provide a critical part of the scientific foundation for EPA’s decision regarding the adequacy of the current primary (health-based) national ambient air quality standards for nitrogen dioxide. The Clean Air Act (CAA) requires EPA to periodically review and revise, as appropriate, existing air quality criteria and NAAQS. The CAA also requires an independent scientific committee to review the criteria and to advise the Administrator regarding any recommended revisions to the existing criteria and standards, as may be appropriate. The Clean Air Scientific Advisory Committee (CASAC) of EPA’s Science Advisory Board serves as this independent scientific committee. The ISA is one of the four major elements of the NAAQS review process that will inform the Agency’s final decisions; other components of the process are an integrated plan highlighting the key policy-relevant issues; a risk/exposure assessment if warranted; and an advance notice of proposed rulemaking (ANPRM) reflecting the Agency’s views regarding options to retain or revise the NO2 NAAQS based on the evaluation of key information cont

  12. Effect of synthesis method on structure, band gap and surface morphology of delafossite oxides, CuAlO2 and CuFeO2

    NASA Astrophysics Data System (ADS)

    Shah, Aadil Abass; Azam, Ameer

    2018-04-01

    In this research work we have reported the synthesis of two different delafossites, CuAlO2 and CuFeO2 by two different synthesis methods viz hydrothermal method and the combustion method. The effect of synthesis on structure, band gap and morphology of the synthesized delafossites was carried out using various techniques. The phase and structure of the synthesized delafossites were studied and confirmed using X-ray diffraction and the crystallite size was calculated. FTIR measurements showed the presence of different stretching modes and functional groups in the synthesized oxides. The surface morphology was studied using the scanning electron microscopy. The band gap of the synthesized delafossite oxides was found to be in the range of 2.8 and 3.3 eV.

  13. Synthesis and biological evaluation of manzamine analogues.

    PubMed

    Winkler, Jeffrey D; Londregan, Allyn T; Ragains, Justin R; Hamann, Mark T

    2006-07-20

    [Structure: see text] The synthesis and biological evaluation of a series of analogues of manzamine A, representing partial structures of the pentacyclic ABCDE diamine core, is described. All new compounds were screened against Plasmodium falciparum and demonstrated attenuated antimalarial activity relative to that of manzamine A.

  14. Investigating the impact of automated feedback on students' scientific argumentation

    NASA Astrophysics Data System (ADS)

    Zhu, Mengxiao; Lee, Hee-Sun; Wang, Ting; Liu, Ou Lydia; Belur, Vinetha; Pallant, Amy

    2017-08-01

    This study investigates the role of automated scoring and feedback in supporting students' construction of written scientific arguments while learning about factors that affect climate change in the classroom. The automated scoring and feedback technology was integrated into an online module. Students' written scientific argumentation occurred when they responded to structured argumentation prompts. After submitting the open-ended responses, students received scores generated by a scoring engine and written feedback associated with the scores in real-time. Using the log data that recorded argumentation scores as well as argument submission and revisions activities, we answer three research questions. First, how students behaved after receiving the feedback; second, whether and how students' revisions improved their argumentation scores; and third, did item difficulties shift with the availability of the automated feedback. Results showed that the majority of students (77%) made revisions after receiving the feedback, and students with higher initial scores were more likely to revise their responses. Students who revised had significantly higher final scores than those who did not, and each revision was associated with an average increase of 0.55 on the final scores. Analysis on item difficulty shifts showed that written scientific argumentation became easier after students used the automated feedback.

  15. Acetabular Cup Revision.

    PubMed

    Kim, Young-Ho

    2017-09-01

    The use of acetabular cup revision arthroplasty is on the rise as demands for total hip arthroplasty, improved life expectancies, and the need for individual activity increase. For an acetabular cup revision to be successful, the cup should gain stable fixation within the remaining supportive bone of the acetabulum. Since the patient's remaining supportive acetabular bone stock plays an important role in the success of revision, accurate classification of the degree of acetabular bone defect is necessary. The Paprosky classification system is most commonly used when determining the location and degree of acetabular bone loss. Common treatment options include: acetabular liner exchange, high hip center, oblong cup, trabecular metal cup with augment, bipolar cup, bulk structural graft, cemented cup, uncemented cup including jumbo cup, acetabular reinforcement device (cage), trabecular metal cup cage. The optimal treatment option is dependent upon the degree of the discontinuity, the amount of available bone stock and the likelihood of achieving stable fixation upon supportive host bone. To achieve successful acetabular cup revision, accurate evaluation of bone defect preoperatively and intraoperatively, proper choice of method of acetabular revision according to the evaluation of acetabular bone deficiency, proper technique to get primary stability of implant such as precise grafting technique, and stable fixation of implant are mandatory.

  16. Accessibility of selenomethionine proteins by total chemical synthesis: structural studies of human herpesvirus-8 MIP-II.

    PubMed

    Shao, W; Fernandez, E; Wilken, J; Thompson, D A; Siani, M A; West, J; Lolis, E; Schweitzer, B I

    1998-12-11

    The determination of high resolution three-dimensional structures by X-ray crystallography or nuclear magnetic resonance (NMR) is a time-consuming process. Here we describe an approach to circumvent the cloning and expression of a recombinant protein as well as screening for heavy atom derivatives. The selenomethionine-modified chemokine macrophage inflammatory protein-II (MIP-II) from human herpesvirus-8 has been produced by total chemical synthesis, crystallized, and characterized by NMR. The protein has a secondary structure typical of other chemokines and forms a monomer in solution. These results indicate that total chemical synthesis can be used to accelerate the determination of three-dimensional structures of new proteins identified in genome programs.

  17. Optimal Full Information Synthesis for Flexible Structures Implemented on Cray Supercomputers

    NASA Technical Reports Server (NTRS)

    Lind, Rick; Balas, Gary J.

    1995-01-01

    This paper considers an algorithm for synthesis of optimal controllers for full information feedback. The synthesis procedure reduces to a single linear matrix inequality which may be solved via established convex optimization algorithms. The computational cost of the optimization is investigated. It is demonstrated the problem dimension and corresponding matrices can become large for practical engineering problems. This algorithm represents a process that is impractical for standard workstations for large order systems. A flexible structure is presented as a design example. Control synthesis requires several days on a workstation but may be solved in a reasonable amount of time using a Cray supercomputer.

  18. Room-temperature Electrochemical Synthesis of Carbide-derived Carbons and Related Materials

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gogotsi, Yury

    2015-02-28

    This project addresses room-temperature electrochemical etching as an energy-efficient route to synthesis of 3D nanoporous carbon networks and layered 2D carbons and related structures, as well as provides fundamental understanding of structure and properties of materials produced by this method. Carbide-derived-carbons (CDCs) are a growing class of nanostructured carbon materials with properties that are desirable for many applications, such as electrical energy and gas storage. The structure of these functional materials is tunable by the choice of the starting carbide precursor, synthesis method, and process parameters. Moving from high-temperature synthesis of CDCs through vacuum decomposition above 1400°C and chlorination abovemore » 400°C, our studies under the previous DOE BES support led to identification of precursor materials and processing conditions for CDC synthesis at temperatures as low as 200°C, resulting in amorphous and highly reactive porous carbons. We also investigated synthesis of monolithic CDC films from carbide films at 250-1200°C. The results of our early studies provided new insights into CDC formation, led to development of materials for capacitive energy storage, and enabled fundamental understanding of the electrolyte ions confinement in nanoporous carbons.« less

  19. The Revised Two-Factor Study Process Questionnaire (R-SPQ-2F): Exploratory and Confirmatory Factor Analyses at Item Level

    ERIC Educational Resources Information Center

    Justicia, Fernando; Pichardo, M. Carmen; Cano, Francisco; Berben, A. B. G.; De la Fuente, Jesus

    2008-01-01

    The underlying structure of the Revised Two Factor version of the Study Process Questionnaire (R-SPQ-2F), a 20-item instrument for the evaluation of students' approaches to learning (SAL), was examined at item level using two independent groups of undergraduate students enrolled in the first (n = 314) and last (n = 522) years of their studies. The…

  20. Self-Instructional Module on Time Utilization. D-1 Revising Existing Structures, Document No. 10g, Revised. Independent Study Training Material for Professional Supervisory Competencies.

    ERIC Educational Resources Information Center

    Giesecke, Carol; And Others

    This self-instructional learning packet is one part of a competency-guided program for instructional supervisor preparation developed by the Special Education Supervisor Training (SEST) project. This packet deals with the study and practice of time utilization as it relates to the supervisor; users of the packet have the opportunity to review and…

  1. The Chinese Version of the Revised Creativity Domain Questionnaire (CDQ-R): First Evidence for Its Factorial Validity and Systematic Association with the Big Five

    ERIC Educational Resources Information Center

    Werner, Christian H.; Tang, Min; Kruse, Joachim; Kaufman, James C.; Spörrle, Matthias

    2014-01-01

    The present study examines the factor structure of a Chinese version of the Revised Creativity Domain Questionnaire (CDQ-R; Kaufman, Waterstreet, Ailaouni, Whitcomb, Roe, & Riggs, 2009) as well as its relation to Big Five personality traits within a Chinese sample (N = 787). Analyses indicate the appropriateness of the Chinese version of the…

  2. Enantioselective synthesis of pactamycin, a complex antitumor antibiotic.

    PubMed

    Malinowski, Justin T; Sharpe, Robert J; Johnson, Jeffrey S

    2013-04-12

    Medicinal application of many complex natural products is precluded by the impracticality of their chemical synthesis. Pactamycin, the most structurally intricate aminocyclopentitol antibiotic, displays potent antiproliferative properties across multiple phylogenetic domains, but it is highly cytotoxic. A limited number of analogs produced by genetic engineering technologies show reduced cytotoxicity against mammalian cells, renewing promise for therapeutic applications. For decades, an efficient synthesis of pactamycin amenable to analog derivatizations has eluded researchers. Here, we present a short asymmetric total synthesis of pactamycin. An enantioselective Mannich reaction and symmetry-breaking reduction sequence was designed to enable assembly of the entire carbon core skeleton in under five steps and control critical three-dimensional (stereochemical) functional group relationships. This modular route totals 15 steps and is immediately amenable for structural analog synthesis.

  3. Validity and reliability of the Malay version multidimensional scale of perceived social support (MSPSS-M) among teachers.

    PubMed

    Lee, Soo Cheng; Moy, Foong Ming; Hairi, Noran Naqiah

    2017-01-01

    The multidimensional scale of perceived social support (MSPSS) was developed to measure perceived social support. It has been translated and culturally adapted among natives literate in the Malay language. However, its psychometric properties for teachers who are majority females and married have not been assessed. This was a cross-sectional study conducted among the public secondary school teachers in the central region of Peninsular Malaysia from May to July 2013. A total of 150 and 203 teachers were recruited to perform exploratory factor analysis and confirmatory factor analysis (CFA), respectively. Reliability testing was evaluated on 141 teachers via internal consistency and two-week interval test-retest. The 12-item three-factor structure of MSPSS-M was revised to 8-item two-factor structure. The revised MSPSS-M demonstrated excellent fit in CFA with adequate divergent and convergent validity and good factor loadings (0.80-0.90). The revised MSPSS-M also displayed good internal consistency with Cronbach's alpha of 0.91, 0.93 and 0.92 and good test-retest reliability with intraclass correlation of 0.89, 0.88 and 0.88 in the total scale, family and friends factors, respectively. The revised 8-item MSPSS-M is a reliable and valid tool for assessment of perceived social support among teachers.

  4. Peloruside B, a Potent Antitumor Macrolide from the New Zealand Marine Sponge Mycale hentscheli: Isolation, Structure, Total Synthesis and Bioactivity

    PubMed Central

    Singh, A. Jonathan; Xu, Chun-Xiao; Xu, Xiaoming; West, Lyndon M.; Wilmes, Anja; Chan, Ariane; Hamel, Ernest; Miller, John H.; Northcote, Peter T.; Ghosh, Arun K.

    2009-01-01

    Peloruside B (2), a natural congener of peloruside A (1), was isolated in sub-milligram quantities from the New Zealand marine sponge Mycale hentscheli. Peloruside B promotes microtubule polymerization and arrests cells in the G2M phase of mitosis similar to paclitaxel, and its bioactivity was comparable to that of peloruside A. NMR-directed isolation, structure elucidation, structure confirmation by total synthesis and bioactivity of peloruside B are described in this article. The synthesis features Sharpless dihydroxylation, Brown's asymmetric allylboration reaction, reductive aldol coupling, Yamaguchi macrolactonization and selective methylation. PMID:19957922

  5. 77 FR 1066 - Information Collection Being Reviewed by the Federal Communications Commission

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-09

    ... provide a pending File Number for an Antenna Structure Registration (ASR). Previously ULS would only...: Application for Antenna Structure Registration. Form Number: FCC Form 854. Type of Review: Revision of a... will be archived after being keyed or scanned into the Antenna Structure Registration (ASR) database...

  6. 78 FR 52419 - Airworthiness Directives; The Boeing Company Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-23

    ... trailing edge flap area that qualify as structural significant items (SSIs). This AD requires revising the... detect and correct fatigue cracking of the wing trailing edge structure, which could result in... within the wing trailing edge flap area that qualify as structural significant items (SSI). We are...

  7. Relations between Minuchin's Structural Family Model and Kohut's Self-Psychology Constructs.

    ERIC Educational Resources Information Center

    Perosa, Linda

    1996-01-01

    Examines relationship between structural family model and self-psychology constructs. College women (n=164) completed the Structural Family Interaction Scale-Revised (SFIS-R), the Parental Relations Inventory, and the Goal Instability and Superiority scales from the Self-Expression Inventory. Indicated that women raised in families with strong…

  8. Self-Study and Evaluation Guide/Revised 1979. Section C-1: Function and Structure.

    ERIC Educational Resources Information Center

    National Accreditation Council for Agencies Serving the Blind and Visually Handicapped, New York, NY.

    The self study guide designed for accreditation of programs serving the blind and visually handicapped covers function and structure standards, standards address five areas: basic characteristics of the organization (legal base, planning, consumer rights), governing authority, the Chief administrator, basic administrative structure (fees for…

  9. Discovery and gram-scale synthesis of BMS-593214, a potent, selective FVIIa inhibitor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Priestley, E. Scott; De Lucca, Indawati; Zhou, Jinglan

    A 6-amidinotetrahydroquinoline screening hit was driven to a structurally novel, potent, and selective FVIIa inhibitor through a combination of library synthesis and rational design. An efficient gram-scale synthesis of the active enantiomer BMS-593214 was developed, which required significant optimization of the key Povarov annulation. Importantly, BMS-593214 showed antithrombotic efficacy in a rabbit arterial thrombosis model. A crystal structure of BMS-593214 bound to FVIIa highlights key contacts with Asp 189, Lys 192, and the S2 pocket.

  10. Drug Development of the Antimalarial Agent Artemisinin: Total Synthesis, Analog Synthesis, and Structure-Activity Relationship Studies

    DTIC Science & Technology

    1990-08-15

    16. SUPPLEMENTARY NOTATION 17 COSATi CODES FiELD 07 06 CROUP 03 01 SUB-GROUP IB SUBJECT TERMS (Cont/nu* on rtvtnt if ntctiwy *ne identity b ...number of requisite substituents resulted in the synthesis of ring cleaved analogs and partial structures of artemisinin: (+)-C/D, (+)-A/ B /C, (+)-A/C...in the preparation of the unstable aldehyde 2, and in commendable fashion others have employed an enol ether photo-oxygenation as entry to that

  11. Exploratory and Confirmatory Factor Analyses of the Structured Interview for Disorders of Extreme Stress

    ERIC Educational Resources Information Center

    Scoboria, Alan; Ford, Julian; Lin, Hsiu-ju; Frisman, Linda

    2008-01-01

    Two studies were conducted to provide the first empirical examination of the factor structure of a revised version of the clinically derived Structured Interview for Disorders of Extreme Stress, a structured interview designed to assess associated features of posttraumatic stress disorder (PTSD) thought to be related to early onset, interpersonal,…

  12. Polyrhythmic Tapping: Examining the Effectiveness of the Strategy of Organizing Rhythmic Structures through Synthesis

    ERIC Educational Resources Information Center

    Yokus, Hamit; Yokus, Tuba

    2015-01-01

    In this study the strategy of organizing rhythmic structures through synthesis is named, and defined, and its procedures are described. Its effectiveness for teaching the execution of 3:2, 4:3, 8:3, 5:4, and 3:5 polyrhythmic structures is examined and described. Pre-test and Post-test Control Group Design was employed to test the effectiveness of…

  13. Revision of seismic design codes corresponding to building damages in the ``5.12'' Wenchuan earthquake

    NASA Astrophysics Data System (ADS)

    Wang, Yayong

    2010-06-01

    A large number of buildings were seriously damaged or collapsed in the “5.12” Wenchuan earthquake. Based on field surveys and studies of damage to different types of buildings, seismic design codes have been updated. This paper briefly summarizes some of the major revisions that have been incorporated into the “Standard for classification of seismic protection of building constructions GB50223-2008” and “Code for Seismic Design of Buildings GB50011-2001.” The definition of seismic fortification class for buildings has been revisited, and as a result, the seismic classifications for schools, hospitals and other buildings that hold large populations such as evacuation shelters and information centers have been upgraded in the GB50223-2008 Code. The main aspects of the revised GB50011-2001 code include: (a) modification of the seismic intensity specified for the Provinces of Sichuan, Shanxi and Gansu; (b) basic conceptual design for retaining walls and building foundations in mountainous areas; (c) regularity of building configuration; (d) integration of masonry structures and pre-cast RC floors; (e) requirements for calculating and detailing stair shafts; and (f) limiting the use of single-bay RC frame structures. Some significant examples of damage in the epicenter areas are provided as a reference in the discussion on the consequences of collapse, the importance of duplicate structural systems, and the integration of RC and masonry structures.

  14. Revised American Thyroid Association guidelines for the management of medullary thyroid carcinoma.

    PubMed

    Wells, Samuel A; Asa, Sylvia L; Dralle, Henning; Elisei, Rossella; Evans, Douglas B; Gagel, Robert F; Lee, Nancy; Machens, Andreas; Moley, Jeffrey F; Pacini, Furio; Raue, Friedhelm; Frank-Raue, Karin; Robinson, Bruce; Rosenthal, M Sara; Santoro, Massimo; Schlumberger, Martin; Shah, Manisha; Waguespack, Steven G

    2015-06-01

    The American Thyroid Association appointed a Task Force of experts to revise the original Medullary Thyroid Carcinoma: Management Guidelines of the American Thyroid Association. The Task Force identified relevant articles using a systematic PubMed search, supplemented with additional published materials, and then created evidence-based recommendations, which were set in categories using criteria adapted from the United States Preventive Services Task Force Agency for Healthcare Research and Quality. The original guidelines provided abundant source material and an excellent organizational structure that served as the basis for the current revised document. The revised guidelines are focused primarily on the diagnosis and treatment of patients with sporadic medullary thyroid carcinoma (MTC) and hereditary MTC. The Task Force developed 67 evidence-based recommendations to assist clinicians in the care of patients with MTC. The Task Force considers the recommendations to represent current, rational, and optimal medical practice.

  15. Revised American Thyroid Association Guidelines for the Management of Medullary Thyroid Carcinoma

    PubMed Central

    Asa, Sylvia L.; Dralle, Henning; Elisei, Rossella; Evans, Douglas B.; Gagel, Robert F.; Lee, Nancy; Machens, Andreas; Moley, Jeffrey F.; Pacini, Furio; Raue, Friedhelm; Frank-Raue, Karin; Robinson, Bruce; Rosenthal, M. Sara; Santoro, Massimo; Schlumberger, Martin; Shah, Manisha; Waguespack, Steven G.

    2015-01-01

    Introduction: The American Thyroid Association appointed a Task Force of experts to revise the original Medullary Thyroid Carcinoma: Management Guidelines of the American Thyroid Association. Methods: The Task Force identified relevant articles using a systematic PubMed search, supplemented with additional published materials, and then created evidence-based recommendations, which were set in categories using criteria adapted from the United States Preventive Services Task Force Agency for Healthcare Research and Quality. The original guidelines provided abundant source material and an excellent organizational structure that served as the basis for the current revised document. Results: The revised guidelines are focused primarily on the diagnosis and treatment of patients with sporadic medullary thyroid carcinoma (MTC) and hereditary MTC. Conclusions: The Task Force developed 67 evidence-based recommendations to assist clinicians in the care of patients with MTC. The Task Force considers the recommendations to represent current, rational, and optimal medical practice. PMID:25810047

  16. Sequence-structure mapping errors in the PDB: OB-fold domains

    PubMed Central

    Venclovas, Česlovas; Ginalski, Krzysztof; Kang, Chulhee

    2004-01-01

    The Protein Data Bank (PDB) is the single most important repository of structural data for proteins and other biologically relevant molecules. Therefore, it is critically important to keep the PDB data, as much as possible, error-free. In this study, we have analyzed PDB crystal structures possessing oligonucleotide/oligosaccharide binding (OB)-fold, one of the highly populated folds, for the presence of sequence-structure mapping errors. Using energy-based structure quality assessment coupled with sequence analyses, we have found that there are at least five OB-structures in the PDB that have regions where sequences have been incorrectly mapped onto the structure. We have demonstrated that the combination of these computation techniques is effective not only in detecting sequence-structure mapping errors, but also in providing guidance to correct them. Namely, we have used results of computational analysis to direct a revision of X-ray data for one of the PDB entries containing a fairly inconspicuous sequence-structure mapping error. The revised structure has been deposited with the PDB. We suggest use of computational energy assessment and sequence analysis techniques to facilitate structure determination when homologs having known structure are available to use as a reference. Such computational analysis may be useful in either guiding the sequence-structure assignment process or verifying the sequence mapping within poorly defined regions. PMID:15133161

  17. Natural products as an inspiration in the diversity-oriented synthesis of bioactive compound libraries

    PubMed Central

    Cordier, Christopher; Morton, Daniel; Murrison, Sarah; O'Leary-Steele, Catherine

    2008-01-01

    The purpose of diversity-oriented synthesis is to drive the discovery of small molecules with previously unknown biological functions. Natural products necessarily populate biologically relevant chemical space, since they bind both their biosynthetic enzymes and their target macromolecules. Natural product families are, therefore, libraries of pre-validated, functionally diverse structures in which individual compounds selectively modulate unrelated macromolecular targets. This review describes examples of diversity-oriented syntheses which have, to some extent, been inspired by the structures of natural products. Particular emphasis is placed on innovations that allow the synthesis of compound libraries that, like natural products, are skeletally diverse. Mimicking the broad structural features of natural products may allow the discovery of compounds that modulate the functions of macromolecules for which ligands are not known. The ability of innovations in diversity-oriented synthesis to deliver such compounds is critically assessed. PMID:18663392

  18. Revision shoulder arthroplasty from resurfacing to non-cemented short-stem reverse prosthesis.

    PubMed

    Natera, L; Bruguera, J; Atoun, E; Levy, O

    2016-01-01

    To assess the surgical parameters and the clinical and radiological outcomes of revisions of resurfacing shoulder arthroplasty to non-cemented short-stem reverse total shoulder arthroplasty. A total of 23 revisions from resurfacing shoulder arthroplasty to reverse total shoulder arthroplasty were performed. The mean age was 70.3±11.95 years. The patients included 82.6% (19/23) revised for cuff failure; 13.04% (3/23) cuff failure and aseptic loosening, and 4.35% (1/23) peri-prosthetic fracture. The need for humeral osteotomy or structural allograft, operation length, blood loss, blood transfusions and intraoperative fractures were recorded. Minimum follow-up 25 months. No humeral osteotomy or humeral structural allograft was required, and 2/23 (8.69%) required allograft for glenoid reconstruction. The mean operation time was 113.35±21.30minutes. Intra-operative blood loss was 374±245.09 mls. Blood transfusion was required in one case. Intra-operative fracture occurred in 1 case. The Constant score improved from 17.32 to 59.78 (age/sex adjusted, 84). Overall satisfaction improved from 1.37 to 8.04. The range of motion increased 79.57° in forward elevation; 72.88° in abduction; 38.06° in internal rotation; and 13.57° in external rotation. There was no evidence of radiolucency, subsidence, or bone resorption. Revisions of resurfacing implants to non-cemented short-stem reverse prosthesis show good clinical and radiological outcomes, with minimal intra-operative complexities. IV, case series. Copyright © 2016 SECOT. Published by Elsevier Espana. All rights reserved.

  19. Geologic Map of the Umiat Quadrangle, Alaska

    USGS Publications Warehouse

    Mull, Charles G.; Houseknecht, David W.; Pessel, G.H.; Garrity, Christopher P.

    2004-01-01

    This geologic map of the Umiat quadrangle is a compilation of previously published USGS geologic maps and unpublished mapping done for the Richfield Oil Corporation. Geologic mapping from these three primary sources was augmented with additional unpublished map data from British Petroleum Company. This report incorporates recent revisions in stratigraphic nomenclature. Stratigraphic and structural interpretations were revised with the aid of modern high-resolution color infrared aerial photographs. The revised geologic map was checked in the field during the summers of 2001 and 2002. The geologic unit descriptions on this map give detailed information on thicknesses, regional distributions, age determinations, and depositional environments. The paper version of this map is available for purchase from the USGS Store.

  20. A new species of Brasineura Silva-Neto & García Aldrete (Psocodea, 'Psocoptera', Ptiloneuridae), with comments on morphological variation in B. troglophilica and a revised generic diagnosis.

    PubMed

    Neto, Alberto Moreira Da Silva; Aldrete, Alfonso N García; Rafael, José Albertino

    2016-03-03

    Brasineura serranortensis sp. n. is here described and illustrated. This is the third known species of Brasineura and differs from the other species in the genus in phallosome, hypandrium and paraproct structure. Comments on variation in fore wing venation, and new records for B. troglophilica are included. A revised generic diagnosis is also presented.

  1. Evidence-based surgery: barriers, solutions, and the role of evidence synthesis.

    PubMed

    Garas, George; Ibrahim, Amel; Ashrafian, Hutan; Ahmed, Kamran; Patel, Vanash; Okabayashi, Koji; Skapinakis, Petros; Darzi, Ara; Athanasiou, Thanos

    2012-08-01

    Surgery is a rapidly evolving field, making the rigorous testing of emerging innovations vital. However, most surgical research fails to employ randomized controlled trials (RCTs) and has particularly been based on low-quality study designs. Subsequently, the analysis of data through meta-analysis and evidence synthesis is particularly difficult. Through a systematic review of the literature, this article explores the barriers to achieving a strong evidence base in surgery and offers potential solutions to overcome the barriers. Many barriers exist to evidence-based surgical research. They include enabling factors, such as funding, time, infrastructure, patient preference, ethical issues, and additionally barriers associated with specific attributes related to researchers, methodologies, or interventions. Novel evidence synthesis techniques in surgery are discussed, including graphics synthesis, treatment networks, and network meta-analyses that help overcome many of the limitations associated with existing techniques. They offer the opportunity to assess gaps and quantitatively present inconsistencies within the existing evidence of RCTs. Poorly or inadequately performed RCTs and meta-analyses can give rise to incorrect results and thus fail to inform clinical practice or revise policy. The above barriers can be overcome by providing academic leadership and good organizational support to ensure that adequate personnel, resources, and funding are allocated to the researcher. Training in research methodology and data interpretation can ensure that trials are conducted correctly and evidence is adequately synthesized and disseminated. The ultimate goal of overcoming the barriers to evidence-based surgery includes the improved quality of patient care in addition to enhanced patient outcomes.

  2. Receptor revision in CD4 T cells is influenced by follicular helper T cell formation and germinal-center interactions.

    PubMed

    Higdon, Lauren E; Deets, Katherine A; Friesen, Travis J; Sze, Kai-Yin; Fink, Pamela J

    2014-04-15

    Peripheral CD4 T cells in Vβ5 transgenic (Tg) C57BL/6J mice undergo tolerance to an endogenous superantigen encoded by mouse mammary tumor virus 8 (Mtv-8) by either deletion or T-cell receptor (TCR) revision. Revision is a process by which surface expression of the Vβ5(+) TCR is down-regulated in response to Mtv-8 and recombination activating genes are expressed to drive rearrangement of the endogenous TCRβ locus, effecting cell rescue through the expression of a newly generated, non-self-reactive TCR. In an effort to identify the microenvironment in which revision takes place, we show here that the proportion of T follicular helper cells (Tfh) and production of high-affinity antibody during a primary response are increased in Vβ5 Tg mice in an Mtv-8-dependent manner. Revising T cells have a Tfh-like surface phenotype and transcription factor profile, with elevated expression of B-cell leukemia/lymphoma 6 (Bcl-6), CXC chemokine receptor 5, programmed death-1, and other Tfh-associated markers. Efficient revision requires Bcl-6 and is inhibited by B lymphocyte-induced maturation protein-1. Revision completes less efficiently in the absence of signaling lymphocytic activation molecule-associated protein although initiation proceeds normally. These data indicate that Tfh formation is required for the initiation of revision and germinal-center interactions for its completion. The germinal center is known to provide a confined space in which B-cell antigen receptors undergo selection. Our data extend the impact of this selective microenvironment into the arena of T cells, suggesting that this fluid structure also provides a regulatory environment in which TCR revision can safely take place.

  3. Synthesis, structure and imaging of oligodeoxyribonucleotides with tellurium-nucleobase derivatization.

    PubMed

    Sheng, Jia; Hassan, Abdalla E A; Zhang, Wen; Zhou, Jianfeng; Xu, Bingqian; Soares, Alexei S; Huang, Zhen

    2011-05-01

    We report here the first synthesis of 5-phenyl-telluride-thymidine derivatives and the Te-phosphoramidite. We also report here the synthesis, structure and STM current-imaging studies of DNA oligonucleotides containing the nucleobases (thymine) derivatized with 5-phenyl-telluride functionality (5-Te). Our results show that the 5-Te-DNA is stable, and that the Te-DNA duplex has the thermo-stability similar to the corresponding native duplex. The crystal structure indicates that the 5-Te-DNA duplex structure is virtually identical to the native one, and that the Te-modified T and native A interact similarly to the native T and A pair. Furthermore, while the corresponding native showed weak signals, the DNA duplex modified with electron-rich tellurium functionality showed strong topographic and current peaks by STM imaging, suggesting a potential strategy to directly image DNA without structural perturbation. © The Author(s) 2011. Published by Oxford University Press.

  4. Synthesis, structure and imaging of oligodeoxyribonucleotides with tellurium-nucleobase derivatization

    PubMed Central

    Sheng, Jia; Hassan, Abdalla E. A.; Zhang, Wen; Zhou, Jianfeng; Xu, Bingqian; Soares, Alexei S.; Huang, Zhen

    2011-01-01

    We report here the first synthesis of 5-phenyl–telluride–thymidine derivatives and the Te-phosphoramidite. We also report here the synthesis, structure and STM current-imaging studies of DNA oligonucleotides containing the nucleobases (thymine) derivatized with 5-phenyl-telluride functionality (5-Te). Our results show that the 5-Te-DNA is stable, and that the Te-DNA duplex has the thermo-stability similar to the corresponding native duplex. The crystal structure indicates that the 5-Te-DNA duplex structure is virtually identical to the native one, and that the Te-modified T and native A interact similarly to the native T and A pair. Furthermore, while the corresponding native showed weak signals, the DNA duplex modified with electron-rich tellurium functionality showed strong topographic and current peaks by STM imaging, suggesting a potential strategy to directly image DNA without structural perturbation. PMID:21245037

  5. Synthesis Structure and Imaging of Oligodeoxyribonucleotides with Tellurium-nucleobase Derivatization

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    J Sheng; A Hassan; W Zhang

    2011-12-31

    We report here the first synthesis of 5-phenyl-telluride-thymidine derivatives and the Te-phosphoramidite. We also report here the synthesis, structure and STM current-imaging studies of DNA oligonucleotides containing the nucleobases (thymine) derivatized with 5-phenyl-telluride functionality (5-Te). Our results show that the 5-Te-DNA is stable, and that the Te-DNA duplex has the thermo-stability similar to the corresponding native duplex. The crystal structure indicates that the 5-Te-DNA duplex structure is virtually identical to the native one, and that the Te-modified T and native A interact similarly to the native T and A pair. Furthermore, while the corresponding native showed weak signals, the DNAmore » duplex modified with electron-rich tellurium functionality showed strong topographic and current peaks by STM imaging, suggesting a potential strategy to directly image DNA without structural perturbation.« less

  6. Synthesis, structure and imaging of oligodeoxyribonucleotides with tellurium-nucleobase derivatization

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sheng, J.; Soares, A.; Hassan, A. E. A.

    2011-05-01

    We report here the first synthesis of 5-phenyl-telluride-thymidine derivatives and the Te-phosphoramidite. We also report here the synthesis, structure and STM current-imaging studies of DNA oligonucleotides containing the nucleobases (thymine) derivatized with 5-phenyl-telluride functionality (5-Te). Our results show that the 5-Te-DNA is stable, and that the Te-DNA duplex has the thermo-stability similar to the corresponding native duplex. The crystal structure indicates that the 5-Te-DNA duplex structure is virtually identical to the native one, and that the Te-modified T and native A interact similarly to the native T and A pair. Furthermore, while the corresponding native showed weak signals, the DNAmore » duplex modified with electron-rich tellurium functionality showed strong topographic and current peaks by STM imaging, suggesting a potential strategy to directly image DNA without structural perturbation.« less

  7. Materials and structures for stretchable energy storage and conversion devices.

    PubMed

    Xie, Keyu; Wei, Bingqing

    2014-06-11

    Stretchable energy storage and conversion devices (ESCDs) are attracting intensive attention due to their promising and potential applications in realistic consumer products, ranging from portable electronics, bio-integrated devices, space satellites, and electric vehicles to buildings with arbitrarily shaped surfaces. Material synthesis and structural design are core in the development of highly stretchable supercapacitors, batteries, and solar cells for practical applications. This review provides a brief summary of research development on the stretchable ESCDs in the past decade, from structural design strategies to novel materials synthesis. The focuses are on the fundamental insights of mechanical characteristics of materials and structures on the performance of the stretchable ESCDs, as well as challenges for their practical applications. Finally, some of the important directions in the areas of material synthesis and structural design facing the stretchable ESCDs are discussed. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Fundamental Studies of Crystal Growth of Microporous Materials

    NASA Technical Reports Server (NTRS)

    Singh, Ramsharan; Doolittle, John, Jr.; Payra, Pramatha; Dutta, Prabir K.; George, Michael A.; Ramachandran, Narayanan; Schoeman, Brian J.

    2003-01-01

    Microporous materials are framework structures with well-defined porosity, often of molecular dimensions. Zeolites contain aluminum and silicon atoms in their framework and are the most extensively studied amongst all microporous materials. Framework structures with P, Ga, Fe, Co, Zn, B, Ti and a host of other elements have also been made. Typical synthesis of microporous materials involve mixing the framework elements (or compounds, thereof) in a basic solution, followed by aging in some cases and then heating at elevated temperatures. This process is termed hydrothermal synthesis, and involves complex chemical and physical changes. Because of a limited understanding of this process, most synthesis advancements happen by a trial and error approach. There is considerable interest in understanding the synthesis process at a molecular level with the expectation that eventually new framework structures will be built by design. The basic issues in the microporous materials crystallization process include: (a) Nature of the molecular units responsible for the crystal nuclei formation; (b) Nature of the nuclei and nucleation process; (c) Growth process of the nuclei into crystal; (d) Morphological control and size of the resulting crystal; (e) Surface structure of the resulting crystals; and (f) Transformation of frameworks into other frameworks or condensed structures.

  9. ACCESS 1: Approximation Concepts Code for Efficient Structural Synthesis program documentation and user's guide

    NASA Technical Reports Server (NTRS)

    Miura, H.; Schmit, L. A., Jr.

    1976-01-01

    The program documentation and user's guide for the ACCESS-1 computer program is presented. ACCESS-1 is a research oriented program which implements a collection of approximation concepts to achieve excellent efficiency in structural synthesis. The finite element method is used for structural analysis and general mathematical programming algorithms are applied in the design optimization procedure. Implementation of the computer program, preparation of input data and basic program structure are described, and three illustrative examples are given.

  10. German Basic Course. Volume II, Lessons 16-25. Revised.

    ERIC Educational Resources Information Center

    Defense Language Inst., Monterey, CA.

    This is the second volume of the intermediate phase of the German Basic Course. The objective of the intermediate phase is mastery of the structural elements of the German language. Accordingly, each lesson contains the following elements: (1) introduction of new structure through "structure perception drills"; (2) a basic dialog dealing with a…

  11. Manufacturing of Smart Structures Using Fiber Placement Manufacturing Processes

    NASA Technical Reports Server (NTRS)

    Thomas, Matthew M.; Glowasky, Robert A.; McIlroy, Bruce E.; Story, Todd A.

    1996-01-01

    Smart structures research and development, with the ultimate aim of rapid commercial and military production of these structures, are at the forefront of the Synthesis and Processing of Intelligent Cost-Effective Structures (SPICES) program. As part of this ARPA-sponsored program, MDA-E is using fiber placement processes to manufacture integrated smart structure systems. These systems comprise advanced composite structures with embedded fiber optic sensors, shape memory alloys, piezoelectric actuators, and miniature accelerometers. Cost-effective approaches and solutions to smart material synthesis in the fiber-placement process, based upon integrated product development, are discussed herein.

  12. A decentralized linear quadratic control design method for flexible structures

    NASA Technical Reports Server (NTRS)

    Su, Tzu-Jeng; Craig, Roy R., Jr.

    1990-01-01

    A decentralized suboptimal linear quadratic control design procedure which combines substructural synthesis, model reduction, decentralized control design, subcontroller synthesis, and controller reduction is proposed for the design of reduced-order controllers for flexible structures. The procedure starts with a definition of the continuum structure to be controlled. An evaluation model of finite dimension is obtained by the finite element method. Then, the finite element model is decomposed into several substructures by using a natural decomposition called substructuring decomposition. Each substructure, at this point, still has too large a dimension and must be reduced to a size that is Riccati-solvable. Model reduction of each substructure can be performed by using any existing model reduction method, e.g., modal truncation, balanced reduction, Krylov model reduction, or mixed-mode method. Then, based on the reduced substructure model, a subcontroller is designed by an LQ optimal control method for each substructure independently. After all subcontrollers are designed, a controller synthesis method called substructural controller synthesis is employed to synthesize all subcontrollers into a global controller. The assembling scheme used is the same as that employed for the structure matrices. Finally, a controller reduction scheme, called the equivalent impulse response energy controller (EIREC) reduction algorithm, is used to reduce the global controller to a reasonable size for implementation. The EIREC reduced controller preserves the impulse response energy of the full-order controller and has the property of matching low-frequency moments and low-frequency power moments. An advantage of the substructural controller synthesis method is that it relieves the computational burden associated with dimensionality. Besides that, the SCS design scheme is also a highly adaptable controller synthesis method for structures with varying configuration, or varying mass and stiffness properties.

  13. Synthesis-Structure-Activity Relationships in Co3O4 Catalyzed CO Oxidation

    NASA Astrophysics Data System (ADS)

    Mingle, Kathleen; Lauterbach, Jochen

    2018-05-01

    In this work, a statistical design and analysis platform was used to develop cobalt oxide based oxidation catalysts prepared via one pot metal salt reduction. An emphasis was placed upon understanding the effects of synthesis conditions, such as heating regimen and Co2+ concentration on the metal salt reduction mechanism, the resultant nanomaterial properties (i.e. size, crystal structure, and crystal faceting), and the catalytic activity in CO oxidation. This was accomplished by carrying out XRD, TEM, and FTIR studies on synthesis intermediates and products. Additionally, high-throughput experimentation was employed to study the performance of Co3O4 oxidation catalysts over a wide range of reaction conditions using a 16-channel fixed bed reactor equipped with a parallel infrared imaging system. Specifically, Co3O4 nanomaterials of varying properties were evaluated for their performance as CO oxidation catalysts. Figure-of-merits including light-off temperatures and activation energies were measured and mapped back to the catalyst properties and synthesis conditions. Statistical analysis methods were used to elucidate significant property-activity relationships as well as the design rules relevant in the synthesis of active catalysts. It was found that CO oxidation light off temperatures could be decreased to <90°C by utilizing the discovered synthesis-structure-activity relationships.

  14. Methodology for Knowledge Synthesis of the Management of Vaccination Pain and Needle Fear.

    PubMed

    Taddio, Anna; McMurtry, C Meghan; Shah, Vibhuti; Yoon, Eugene W; Uleryk, Elizabeth; Pillai Riddell, Rebecca; Lang, Eddy; Chambers, Christine T; Noel, Melanie; MacDonald, Noni E

    2015-10-01

    A knowledge synthesis was undertaken to inform the development of a revised and expanded clinical practice guideline about managing vaccination pain in children to include the management of pain across the lifespan and the management of fear in individuals with high levels of needle fear. This manuscript describes the methodological details of the knowledge synthesis and presents the list of included clinical questions, critical and important outcomes, search strategy, and search strategy results. The Grading of Assessments, Recommendations, Development and Evaluation (GRADE) and Cochrane methodologies provided the general framework. The project team voted on clinical questions for inclusion and critically important and important outcomes. A broad search strategy was used to identify relevant randomized-controlled trials and quasi-randomized-controlled trials. Quality of research evidence was assessed using the Cochrane risk of bias tool and quality across studies was assessed using GRADE. Multiple measures of the same construct within studies (eg, observer-rated and parent-rated infant distress) were combined before pooling. The standardized mean difference and 95% confidence intervals (CI) or relative risk and 95% CI was used to express the effects of an intervention. Altogether, 55 clinical questions were selected for inclusion in the knowledge synthesis; 49 pertained to pain management during vaccine injections and 6 pertained to fear management in individuals with high levels of needle fear. Pain, fear, and distress were typically prioritized as critically important outcomes across clinical questions. The search strategy identified 136 relevant studies. This manuscript describes the methodological details of a knowledge synthesis about pain management during vaccination and fear management in individuals with high levels of needle fear. Subsequent manuscripts in this series will present the results for the included questions.

  15. Integrated Science Assessment (ISA) for Oxides of Nitrogen ...

    EPA Pesticide Factsheets

    EPA announced the availability of the final report, Integrated Science Assessment (ISA) for Oxides of Nitrogen and Sulfur - Ecological Criteria. This document represents a concise synthesis and evaluation of the most policy-relevant science and will ultimately provide the scientific bases for EPA's decision on retaining or revising the current secondary standards for oxides of nitrogen (NO2 and SO2). The intent of the ISA, according to the CAA, is to “accurately reflect the latest scientific knowledge expected from the presence of [a] pollutant in ambient air” (U.S. Code, 1970a, 1970b). It includes scientific research from atmospheric sciences, exposure and deposition, biogeochemistry, hydrology, soil science, marine science, plant physiology, animal physiology, and ecology conducted at multiple scales (e.g., population, community, ecosystem, landscape levels). Key information and judgments formerly found in the Air Quality Criteria Documents (AQCDs) for NOX and SOX are included; Annexes provide a more detailed discussion of the most pertinent scientific literature. Together, the ISA and Annexes serve to update and revise the last NOX and SOX AQCDs which were published in 1993 and 1982, respectively.

  16. Introducing Risk Management Techniques Within Project Based Software Engineering Courses

    NASA Astrophysics Data System (ADS)

    Port, Daniel; Boehm, Barry

    2002-03-01

    In 1996, USC switched its core two-semester software engineering course from a hypothetical-project, homework-and-exam course based on the Bloom taxonomy of educational objectives (knowledge, comprehension, application, analysis, synthesis, and evaluation). The revised course is a real-client team-project course based on the CRESST model of learning objectives (content understanding, problem solving, collaboration, communication, and self-regulation). We used the CRESST cognitive demands analysis to determine the necessary student skills required for software risk management and the other major project activities, and have been refining the approach over the last 5 years of experience, including revised versions for one-semester undergraduate and graduate project course at Columbia. This paper summarizes our experiences in evolving the risk management aspects of the project course. These have helped us mature more general techniques such as risk-driven specifications, domain-specific simplifier and complicator lists, and the schedule as an independent variable (SAIV) process model. The largely positive results in terms of review of pass / fail rates, client evaluations, product adoption rates, and hiring manager feedback are summarized as well.

  17. Effect of synthesis conditions on the nanopowder properties of Ce{sub 0.9}Zr{sub 0.1}O{sub 2}

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zimicz, M.G.; Fabregas, I.O.; Lamas, D.G.

    Graphical abstract: . The synthesis of nanocrystalline Ce{sub 0.9}Zr{sub 0.1}O{sub 2} powders via the gel-combustion method, using different fuels, and following either stoichiometric or non-stoichiometric pH-controlled routes is investigated. Research highlights: {yields} All samples exhibited the fluorite-type crystal structure, nanometric average crystallite size and negligible carbon content. {yields} Synthesis conditions strongly affect the average crystallite size, the degree of agglomeration, the specific surface area and the pore volume. {yields} Our results indicate that, by controlling the synthesis conditions it is possible to obtain solids with custom-made morphological properties. -- Abstract: In this work, the synthesis of nanocrystalline Ce{sub 0.9}Zr{sub 0.1}O{submore » 2} powders via the gel-combustion method, using different fuels, and following either stoichiometric or non-stoichiometric pH-controlled routes is investigated. The objective is to evaluate the effect of synthesis conditions on the textural and morphological properties, and the crystal structure of the synthesized materials. The solids were characterized by nitrogen physisorption, Scanning Electron Microscopy (SEM), X-ray powder diffraction (XPD), and Carbon-Hydrogen-Nitrogen Elemental Analysis (CHN). All the powders exhibited nanometric crystallite size, fluorite-type structure and negligible carbon content. Synthesis conditions strongly affect the average crystallite size, the degree of agglomeration, the specific surface area and the pore volume. Our results indicate that, by controlling the synthesis conditions it is possible to obtain solids with custom-made morphological properties.« less

  18. Rapid and Convenient Synthesis of the 1,4-Dihydropyridine Privileged Structure

    ERIC Educational Resources Information Center

    Cheung, Lawrence L. W.; Styler, Sarah A.; Dicks, Andrew P.

    2010-01-01

    A short, semi-microscale synthesis of two 1,4-dihydropyridine drug analogues via a Hantzsch reaction is described, which is appropriate for a second-year undergraduate organic laboratory. Products are specifically chosen to highlight the biological relevance of this compound type while introducing the notion of a privileged structure.…

  19. Synthesis of "Meso"-Diethyl-2,2'-Dipyrromethane in Water: An Experiment in Green Organic Chemistry

    ERIC Educational Resources Information Center

    Sobral, Abilio J. F. N.

    2006-01-01

    Dipyrromethanes (or dipyrrilmethanes) are important building blocks for many of the structures of interest in the areas of porphyrins, materials science, optics, and medicine. A variety of conditions have been established for the synthesis of dipyrromethanes of diverse structures, from substituted pyrroles to unsubstituted pyrrole and carbonyl…

  20. Oligomeric flavanoids. Part 26. Structure and synthesis of the first profisetinidins with epifisetinidol constituent units

    Treesearch

    Petrus J. Steynberg; Jan P. Steynberg; E. Vincent Brandt; Daneel Ferreira; Richard W. Hemingway

    1997-01-01

    The natural occurrence of the first oligomeric profisetinidins with (2R,3R}-2,3-cis-epifisetinidol chain extender units is demonstrated in the bark of Pithecellobium dulce (Guamuchil). Semi-synthesis using the appropriate flavan-3-ol and flavan-3,4-diol precursors permits unequivocal structural...

  1. 77 FR 58931 - Technical Corrections Relating to the Rules of Origin for Goods Imported Under the NAFTA and for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-25

    ... from subheading 3502.90; or A change to peptones and their derivatives, other protein substances and..., prostagladins, thromboxanes and leukotrienes, natural or reproduced by synthesis, derivatives and structural..., thromboxanes and leukotrienes, natural or reproduced by synthesis or derivatives, and structural analogues...

  2. Children's high-level writing skills: development of planning and revising and their contribution to writing quality.

    PubMed

    Limpo, Teresa; Alves, Rui A; Fidalgo, Raquel

    2014-06-01

    It is well established that the activity of producing a text is a complex one involving three main cognitive processes: Planning, translating, and revising. Although these processes are crucial in skilled writing, beginning and developing writers seem to struggle with them, mainly with planning and revising. To trace the development of the high-level writing processes of planning and revising, from Grades 4 to 9, and to examine whether these skills predict writing quality in younger and older students (Grades 4-6 vs. 7-9), after controlling for gender, school achievement, age, handwriting fluency, spelling, and text structure. Participants were 381 students from Grades 4 to 9 (age 9-15). Students were asked to plan and write a story and to revise another story by detecting and correcting mechanical and substantive errors. From Grades 4 to 9, we found a growing trend in students' ability to plan and revise despite the observed decreases and stationary periods from Grades 4 to 5 and 6 to 7. Moreover, whereas younger students' planning and revising skills made no contribution to the quality of their writing, in older students, these high-level skills contributed to writing quality above and beyond control predictors. The findings of this study seem to indicate that besides the increase in planning and revising, these skills are not fully operational in school-age children. Indeed, given the contribution of these high-level skills to older students' writing, supplementary instruction and practice should be provided from early on. © 2013 The British Psychological Society.

  3. Synthesis facilitates an understanding of the structural basis for translation inhibition by the lissoclimides

    NASA Astrophysics Data System (ADS)

    Könst, Zef A.; Szklarski, Anne R.; Pellegrino, Simone; Michalak, Sharon E.; Meyer, Mélanie; Zanette, Camila; Cencic, Regina; Nam, Sangkil; Voora, Vamsee K.; Horne, David A.; Pelletier, Jerry; Mobley, David L.; Yusupova, Gulnara; Yusupov, Marat; Vanderwal, Christopher D.

    2017-11-01

    The lissoclimides are unusual succinimide-containing labdane diterpenoids that were reported to be potent cytotoxins. Our short semisynthesis and analogue-oriented synthesis approaches provide a series of lissoclimide natural products and analogues that expand the structure-activity relationships (SARs) in this family. The semisynthesis approach yielded significant quantities of chlorolissoclimide (CL) to permit an evaluation against the National Cancer Institute's 60-cell line panel and allowed us to obtain an X-ray co-crystal structure of the synthetic secondary metabolite with the eukaryotic 80S ribosome. Although it shares a binding site with other imide-based natural product translation inhibitors, CL engages in a particularly interesting and novel face-on halogen-π interaction between the ligand's alkyl chloride and a guanine residue. Our analogue-oriented synthesis provides many more lissoclimide compounds, which were tested against aggressive human cancer cell lines and for protein synthesis inhibitory activity. Finally, computational modelling was used to explain the SARs of certain key compounds and set the stage for the structure-guided design of better translation inhibitors.

  4. Organization of Genes Required for the Oxidation of Methanol to Formaldehyde in Three Type II Methylotrophs

    PubMed Central

    Bastien, C.; Machlin, S.; Zhang, Y.; Donaldson, K.; Hanson, R. S.

    1989-01-01

    Restriction maps of genes required for the synthesis of active methanol dehydrogenase in Methylobacterium organophilum XX and Methylobacterium sp. strain AM1 have been completed and compared. In these two species of pink-pigmented, type II methylotrophs, 15 genes were identified that were required for the expression of methanol dehydrogenase activity. None of these genes were required for the synthesis of the prosthetic group of methanol dehydrogenase, pyrroloquinoline quinone. The structural gene required for the synthesis of cytochrome cL, an electron acceptor uniquely required for methanol dehydrogenase, and the genes encoding small basic peptides that copurified with methanol dehydrogenases were closely linked to the methanol dehydrogenase structural genes. A cloned 22-kilobase DNA insert from Methylsporovibrio methanica 81Z, an obligate type II methanotroph, complemented mutants that contained lesions in four genes closely linked to the methanol dehydrogenase structural genes. The methanol dehydrogenase and cytochrome cL structural genes were found to be transcribed independently in M. organophilum XX. Only two of the genes required for methanol dehydrogenase synthesis in this bacterium were found to be cotranscribed. PMID:16348074

  5. Chemical synthesis and NMR characterization of structured polyunsaturated triacylglycerols.

    PubMed

    Fauconnot, Laëtitia; Robert, Fabien; Villard, Renaud; Dionisi, Fabiola

    2006-02-01

    The chemical synthesis of pure triacylglycerol (TAG) regioisomers, that contain long chain polyunsaturated fatty acids, such as arachidonic acid (AA) or docosahexaenoic acid (DHA), and saturated fatty acids, such as lauric acid (La) or palmitic acid (P), at defined positions, is described. A single step methodology using (benzotriazol-1-yloxy)-tripyrrolidinophosphonium hexafluorophosphate (PyBOP), an activator of carboxyl group commonly used in peptide synthesis and occasionally used in carboxylic acid esterification, has been developed for structured TAG synthesis. Identification of the fatty acyl chains for each TAG species was confirmed by atmospheric pressure chemical ionisation mass spectrometry (APCI-MS) and fatty acid positional distribution was determined by (1)H and (13)C NMR spectra. The generic described procedures can be applied to a large variety of substrates and was used for the production of specific triacylglycerols of defined molecular structures, with high regioisomeric purity. Combination of MS and NMR was shown to be an efficient tool for structural analysis of TAG. In particular, some NMR signals were demonstrated to be regioisomer specific, allowing rapid positional analysis of LC-PUFA containing TAG.

  6. [Management of chronic heart failure - a systematic review of guidelines in the context of the DMP revision].

    PubMed

    Kötter, Thomas; Bartel, Carmen; Schramm, Susanne; Lange, Petra; Höfer, Eva; Hänsel, Michaela; Waffenschmidt, Siw; Waldt, Susanne Ein; Hoffmann-Eßer, Wiebke; Rüther, Alric; Lühmann, Dagmar; Scherer, Martin

    2013-01-01

    Disease Management Programmes (DMPs) are structured treatment programmes for chronic diseases. The DMP requirements are primarily derived from evidence-based guidelines. DMPs are regularly revised to ensure that they reflect current best practice and medical knowledge. The aim of this study was to assess the need for updating the German DMP module on heart failure by comparing it to relevant guidelines and identifying recommendations that should be revised. We systematically searched for clinical guidelines on heart failure published in German, English or French, and extracted relevant guideline recommendations. All included guidelines were assessed for methodological quality. To identify revision needs in the DMP, we performed a synoptic analysis of the extracted guideline recommendations and DMP requirements. 27 guidelines were included. The extracted recommendations covered all aspects of the management of heart failure. The comparison of guideline recommendations with DMP requirements showed that, overall, guideline recommendations were more detailed than DMP requirements, and that the guidelines covered topics not included in the DMP module. The DMP module is largely consistent with current guidelines on heart failure. We did not identify any need for significant revision of the DMP requirements. However, some specific recommendations of the DMP module could benefit from revision. Copyright © 2013. Published by Elsevier GmbH.

  7. Synthesis and Characterisation of Hollow Spherical Nano- and Microparticles with Silica and Magnetite

    NASA Astrophysics Data System (ADS)

    Gorbyk, P. P.; Dubrovin, I. V.; Demchenko, Yu. A.

    The main principles and methods of synthesis of hollow structures with inorganic nanomaterials are described. Synthesis of hollow spherical silica particles was based on hydrolysis of Si(CH3)2Cl2 and SiCl4 in nonpolar solvents at a surface of aerosol drops. To synthesise hollow magnetite nano- and microparticles with magnetite, saturated solution of iron chlorides in acetone was used. Phase and element composition, morphology and structure of samples were studied using XRD, Auger electron spectroscopy, scanning electron and atom force microscopies.

  8. The Structure of Social Exchange in Self-Help Support Groups: Development of a Measure

    PubMed Central

    Brown, Louis D.; Tang, Xiaohui; Hollman, Ruth L.

    2014-01-01

    Self-help support groups are indigenous community resources designed to help people manage a variety of personal challenges, from alcohol abuse to xeroderma pigmentosum. The social exchanges that occur during group meetings are central to understanding how people benefit from participation. This paper examines the different types of social exchange behaviors that occur during meetings, using two studies to develop empirically distinct scales that reliably measure theoretically important types of exchange. Resource theory informed the initial measurement development efforts. Exploratory factor analyses from the first study led to revisions in the factor structure of the social exchange scales. The revised measure captured the exchange of emotional support, experiential information, humor, unwanted behaviors, and exchanges outside meetings. Confirmatory factor analyses from a follow-up study with a different sample of self-help support groups provided good model fit, suggesting the revised structure accurately represented the data. Further, the scales demonstrated good convergent and discriminant validity with related constructs. Future research can use the scales to identify aspects of social exchange that are most important in improving health outcomes among self-help support group participants. Groups can use the scales in practice to celebrate strengths and address weaknesses in their social exchange dynamics. PMID:24398622

  9. Carbon nanopipettes and microtubes for electrochemical sensing and microfluidics

    NASA Astrophysics Data System (ADS)

    Mani, Radhika C.; Bhimarasetti, Gopinath; Lowe, Randall; Sunkara, Mahendra K.

    2004-12-01

    We present the synthesis of two novel morphologies for carbon tubular structures: Nanopipettes and Micropipes. The synthesis procedures for both these structures are both unique and different from each other and the conventional methods used for carbon nanotubes. Carbon nanopipettes, open at both ends, are made up of a central nanotube (~10-20 nm) surrounded by helical sheets of graphite. Thus nanopipettes have an outer conical structure, with a base size of about a micron, that narrows down to about 10-20 nm at the tip. Due to their unique morphology, the outer walls of the nanopipettes continuously expose edge planes of graphite, giving a very stable and reversible electrochemical response for detecting neurological compounds such as dopamine. The synthesis of carbon nanopipettes is based on high temperature nucleation and growth of carbon nanotubes under conditions of hydrogen etching during growth. Carbon micropipes, on the other hand, are tubular structures whose internal diameters range from a few nanometers to a few microns with a constant wall thickness of 10-20 nm. In addition to tuning the internal diameters, the conical angles of these structures could also be changed during synthesis. Due to their larger inner diameters and thin walls, both the straight and conical micro-tubular structures are suitable for microfluidic devices such as throttle valves, micro-reactors, and distribution channels. The synthesis of carbon micro-tubular structures is based on the wetting behavior of gallium with carbon during growth. The contact angle between gallium and the carbon wall determines the conical angle of the structure. By varying the contact angle, one can alter the conical angles from 400 to -150, and synthesize straight tubes using different N2/O2 dosing compositions. An 'n-step' dosing sequence at various stages of growth resulted in 'n-staged' morphologies for carbon micro-tubular structures such as funnels, tube-on-cone, Y-junctions and dumbbells.

  10. Structure tracking aided design and synthesis of Li 3V 2(PO 4) 3 nanocrystals as high-power cathodes for lithium ion batteries

    DOE PAGES

    Wang, Liping; Bai, Jianming; Gao, Peng; ...

    2015-07-30

    In this study, preparing new electrode materials with synthetic control of phases and electrochemical properties is desirable for battery applications but hardly achievable without knowing how the synthesis reaction proceeds. Herein, we report on structure tracking-aided design and synthesis of single-crystalline Li 3V 2(PO 4) 3 (LVP) nanoparticles with extremely high rate capability. A comprehensive investigation was made to the local structural orderings of the involved phases and their evolution toward forming LVP phase using in situ/ex situ synchrotron X-ray and electron-beam diffraction, spectroscopy, and imaging techniques. The results shed light on the thermodynamics and kinetics of synthesis reactions andmore » enabled the design of a cost-efficient synthesis protocol to make nanocrystalline LVP, wherein solvothermal treatment is a crucial step leading to an amorphous intermediate with local structural ordering resembling that of LVP, which, upon calcination at moderate temperatures, rapidly transforms into the desired LVP phase. The obtained LVP particles are about 50 nm, coated with a thin layer of amorphous carbon and featured with excellent cycling stability and rate capability – 95% capacity retention after 200 cycles and 66% theoretical capacity even at a current rate of 10 C. The structure tracking based method we developed in this work offers a new way of designing battery electrodes with synthetic control of material phases and properties.« less

  11. Polyphenylquinoxalines Via Aromatic Nucleophilic Displacement

    NASA Technical Reports Server (NTRS)

    Hergenrother, Paul M.; Connell, John W.

    1991-01-01

    Process for synthesis of polyphenylquinoxalines (PPQ's) involves nucleophilic displacement reactions of di(hydroxyphenyl) quinoxaline monomers with activated aromatic dihalides. New process costs less than other processes for synthesis of PPQ's. Facilitates synthesis of PPQ's of new and varied molecular structures. Useful as adhesives, coatings, films, membranes, and matrices for composites.

  12. The TosMIC approach to 3-(oxazol-5-yl) indoles: application to the synthesis of indole-based IMPDH inhibitors.

    PubMed

    Dhar, T G Murali; Shen, Zhongqi; Fleener, Catherine A; Rouleau, Katherine A; Barrish, Joel C; Hollenbaugh, Diane L; Iwanowicz, Edwin J

    2002-11-18

    A modified approach to the synthesis of 3-(oxazolyl-5-yl) indoles is reported. This method was applied to the synthesis of series of novel indole based inhibitors of inosine monophosphate dehydrogenase (IMPDH). The synthesis and the structure-activity relationships (SARs), derived from in vitro studies, for this new series of inhibitors is given.

  13. Synthesis of the C(18) -norditerpenoid alkaloid neofinaconitine: a lesson in convergent synthesis planning.

    PubMed

    Liu, Xiao-Yu; Chen, David Y-K

    2014-01-20

    Hexacyclic framework: The total synthesis of the complex C18 -norditerpenoid alkaloid neofinaconitine has been achieved by a convergent approach. This remarkable synthesis featured two Diels-Alder cycloadditions and subsequent Mannich-type N-acyliminium and radical cyclizations to establish the unique hexacyclic core structure of the target molecule. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Psychometric Properties of the Persian Version of the Difficulties in Emotion Regulation Scale) DERS-6 & DERS-5- Revised (in an Iranian Clinical Sample.

    PubMed

    Mazaheri, Mina

    2015-04-01

    The purpose of this study was to determine the construct validity and reliability of the two forms of the Persian version of the Difficulties in Emotion Regulation Scale (DERS-6 & DERS-5-revised) in a clinical sample. The clinical sample consisted of 181 patients diagnosed with Functional GI Disorders (FGID) who referred to the digestive psychosomatic clinic in Isfahan in 2012. They were selected by census method (In a given period of time). The Persian version of the DERS, the short form of the DASS, and the TAS-20 were used to collect data. The results of the factor structure or construct validity using principal components analysis with varimax rotation recognized 7 factors for the DERS-6 (Goals, Awarness, Impalse, Non Acceptance, Strategy, Clarity, Recognition), and 6 factors for the DERS-5- revised (Non Acceptance, Goals, Impalse, Strategy, Clarity, Recognition) in the clinical sample. They showed the common variance of 59.51% and 59.15%, respectively. Also, the results showed that the concurrent validity of both forms of the DERS and most of their factors, and their reliability in terms of Cronbach-Alpha were favorable. Considering the factor structure and favorable psychometric properties of the two scales of DERS-6 & DERS-5-revised, the scales can be used in clinical samples.

  15. Cell-free synthesis of membrane subunits of ATP synthase in phospholipid bicelles: NMR shows subunit a fold similar to the protein in the cell membrane

    PubMed Central

    Uhlemann, Eva-Maria E; Pierson, Hannah E; Fillingame, Robert H; Dmitriev, Oleg Y

    2012-01-01

    NMR structure determination of large membrane proteins is hampered by broad spectral lines, overlap, and ambiguity of signal assignment. Chemical shift and NOE assignment can be facilitated by amino acid selective isotope labeling in cell-free protein synthesis system. However, many biological detergents are incompatible with the cell-free synthesis, and membrane proteins often have to be synthesized in an insoluble form. We report cell-free synthesis of subunits a and c of the proton channel of Escherichia coli ATP synthase in a soluble form in a mixture of phosphatidylcholine derivatives. In comparison, subunit a was purified from the cell-free system and from the bacterial cell membranes. NMR spectra of both preparations were similar, indicating that our procedure for cell-free synthesis produces protein structurally similar to that prepared from the cell membranes. PMID:22162071

  16. One-step synthesis and structural features of CdS/montmorillonite nanocomposites.

    PubMed

    Han, Zhaohui; Zhu, Huaiyong; Bulcock, Shaun R; Ringer, Simon P

    2005-02-24

    A novel synthesis method was introduced for the nanocomposites of cadmium sulfide and montmorillonite. This method features the combination of an ion exchange process and an in situ hydrothermal decomposition process of a complex precursor, which is simple in contrast to the conventional synthesis methods that comprise two separate steps for similar nanocomposite materials. Cadmium sulfide species in the composites exist in the forms of pillars and nanoparticles, the crystallized sulfide particles are in the hexagonal phase, and the sizes change when the amount of the complex for the synthesis is varied. Structural features of the nanocomposites are similar to those of the clay host but changed because of the introduction of the sulfide into the clay.

  17. The GEM Global Active Faults Database: The growth and synthesis of a worldwide database of active structures for PSHA, research, and education

    NASA Astrophysics Data System (ADS)

    Styron, R. H.; Garcia, J.; Pagani, M.

    2017-12-01

    A global catalog of active faults is a resource of value to a wide swath of the geoscience, earthquake engineering, and hazards risk communities. Though construction of such a dataset has been attempted now and again through the past few decades, success has been elusive. The Global Earthquake Model (GEM) Foundation has been working on this problem, as a fundamental step in its goal of making a global seismic hazard model. Progress on the assembly of the database is rapid, with the concatenation of many national—, orogen—, and continental—scale datasets produced by different research groups throughout the years. However, substantial data gaps exist throughout much of the deforming world, requiring new mapping based on existing publications as well as consideration of seismicity, geodesy and remote sensing data. Thus far, new fault datasets have been created for the Caribbean and Central America, North Africa, and northeastern Asia, with Madagascar, Canada and a few other regions in the queue. The second major task, as formidable as the initial data concatenation, is the 'harmonization' of data. This entails the removal or recombination of duplicated structures, reconciliation of contrastinginterpretations in areas of overlap, and the synthesis of many different types of attributes or metadata into a consistent whole. In a project of this scale, the methods used in the database construction are as critical to project success as the data themselves. After some experimentation, we have settled on an iterative methodology that involves rapid accumulation of data followed by successive episodes of data revision, and a computer-scripted data assembly using GIS file formats that is flexible, reproducible, and as able as possible to cope with updates to the constituent datasets. We find that this approach of initially maximizing coverage and then increasing resolution is the most robust to regional data problems and the most amenable to continued updates and refinement. Combined with the public, open-source nature of this project, GEM is producing a resource that can continue to evolve with the changing knowledge and needs of the community.

  18. Enhanced Stereoselectivity of a Cu(II) Complex Chiral Auxiliary in the Synthesis of Fmoc-L-γ-carboxyglutamic Acid | Center for Cancer Research

    Cancer.gov

    Bridging bioinorganic chemistry with asymmetric synthesis: a naturally occurring metalloprotein is used for the structure-based evolution of chiral auxiliaries that prove to be effective in the synthesis of Fmoc-L-γ-carboxyglutamic acid.

  19. 76 FR 7818 - Correction to Notice Soliciting Comments on Proposed Voluntary Product Standard PS 2-10 and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-11

    ... ``Performance Standard for Wood-Based Structural-Use Panels,'' and appears in the body of the notice. NIST is... correct title of the proposed standard is ``Performance Standard for Wood-Based Structural-Use Panels... Product Standard (PS) 2-04, Performance Standard for Wood-Based Structural-Use Panels. This revised...

  20. The Cylindrical Structure of the Wechsler Intelligence Scale for Children--IV: A Retest of the Guttman Model of Intelligence

    ERIC Educational Resources Information Center

    Cohen, Arie; Fiorello, Catherine A.; Farley, Frank H.

    2006-01-01

    A previous study on the underlying structure of the Wechsler intelligence test (WISC-R; [Wechsler, D. (1974). Manual WISC-R: Wechsler intelligence scale for children-Revised. New York: Psychological Corporation]), using smallest space analysis (SSA) [Guttman, L., and Levy, S. (1991). Two structural laws for intelligence tests.…

  1. Software Methodology Catalog. Second Edition. Revision

    DTIC Science & Technology

    1989-03-01

    structured design involve characterization of the data flow through graphical representation, identification of the various transform elements, assembling...and graphical diagrams to facilitate communication within the team. The diagrams are consistent with the design language and can be automatically...organization, box structure graphics provide a visual means of client communication. These box structures are used during analysis and design to review

  2. Structure Diversity, Synthesis, and Biological Activity of Cyathane Diterpenoids in Higher Fungi.

    PubMed

    Tang, Hao-Yu; Yin, Xia; Zhang, Cheng-Chen; Jia, Qian; Gao, Jin-Ming

    2015-01-01

    Cyathane diterpenoids, occurring exclusively in higher basidiomycete (mushrooms), represent a structurally diverse class of natural products based on a characteristic 5-6-7 tricyclic carbon scaffold, including 105 members reported to date. These compounds show a diverse range of biological activities, such as antimicrobial, anti-MRSA, agonistic toward the kappa-opioid receptor, antiinflammatory, anti-proliferative and nerve growth factor (NGF)-like properties. The present review focuses on the structure diversity, structure elucidation and biological studies of these compounds, including mechanisms of actions and structure-activity relationships (SARs). In addition, new progress in chemical synthesis of cyathane diterpenoids is discussed.

  3. Test, revision, and cross-validation of the Physical Activity Self-Definition Model.

    PubMed

    Kendzierski, Deborah; Morganstein, Mara S

    2009-08-01

    Structural equation modeling was used to test an extended version of the Kendzierski, Furr, and Schiavoni (1998) Physical Activity Self-Definition Model. A revised model using data from 622 runners fit the data well. Cross-validation indices supported the revised model, and this model also provided a good fit to data from 397 cyclists. Partial invariance was found across activities. In both samples, perceived commitment and perceived ability had direct effects on self-definition, and perceived wanting, perceived trying, and enjoyment had indirect effects. The contribution of perceived ability to self-definition did not differ across activities. Implications concerning the original model, indirect effects, skill salience, and the role of context in self-definition are discussed.

  4. A template-free solvent-mediated synthesis of high surface area boron nitride nanosheets for aerobic oxidative desulfurization.

    PubMed

    Wu, Peiwen; Zhu, Wenshuai; Chao, Yanhong; Zhang, Jinshui; Zhang, Pengfei; Zhu, Huiyuan; Li, Changfeng; Chen, Zhigang; Li, Huaming; Dai, Sheng

    2016-01-04

    Hexagonal boron nitride nanosheets (h-BNNs) with rather high specific surface area (SSA) are important two-dimensional layer-structured materials. Here, a solvent-mediated synthesis of h-BNNs revealed a template-free lattice plane control strategy that induced high SSA nanoporous structured h-BNNs with outstanding aerobic oxidative desulfurization performance.

  5. New Approach to Synthesis of Powder and Composite Materials by Electron Beam. Part 1. Technological Features of the Process

    NASA Astrophysics Data System (ADS)

    Rudskoy, A. I.; Kondrat'ev, S. Yu.; Sokolov, Yu. A.

    2016-05-01

    Possibilities of electron beam synthesis of structural and tool composite materials are considered. It is shown that a novel process involving mathematical modeling of each individual operation makes it possible to create materials with programmable structure and predictable properties from granules of various specified chemical compositions and sizes.

  6. A preliminary synthesis of structural, stratigraphic, and magnetic data from part of the northwest Adirondacks, New York

    USGS Publications Warehouse

    Foose, M.P.; Brown, C. Ervin

    1976-01-01

    Synthesis of recent work in the NW Adirondacks, New York allows the development of a coherent geologic picture. Mapping of the Precambrian rock units enables the recognition of four major units which are, from bottom to top, 1) Granitic Gneiss (alaskite), 2) Lower Marble, 3) Major Gneiss, and 4) Upper Marble. Additionally, lenses of amphibolite and granite occur as intrusives within this succession. These rock units have been complexly deformed by three major folding episodes, and by two distinctly different styles of faulting. The result has been to produce large northeast-southwest trending dome and basin structures. Patterns of magnetic intensity closely parallel distribution of rock units and provide additional information for a structural and stratigraphic synthesis-.

  7. Microfluidic approach toward continuous and ultrafast synthesis of metal-organic framework crystals and hetero structures in confined microdroplets.

    PubMed

    Faustini, Marco; Kim, Jun; Jeong, Guan-Young; Kim, Jin Yeong; Moon, Hoi Ri; Ahn, Wha-Seung; Kim, Dong-Pyo

    2013-10-02

    Herein, we report a novel nanoliter droplet-based microfluidic strategy for continuous and ultrafast synthesis of metal-organic framework (MOF) crystals and MOF heterostructures. Representative MOF structures, such as HKUST-1, MOF-5, IRMOF-3, and UiO-66, were synthesized within a few minutes via solvothermal reactions with substantially faster kinetics in comparison to the conventional batch processes. The approach was successfully extended to the preparation of a demanding Ru3BTC2 structure that requires high-pressure hydrothermal synthesis conditions. Finally, three different types of core-shell MOF composites, i.e., Co3BTC2@Ni3BTC2, MOF-5@diCH3-MOF-5, and Fe3O4@ZIF-8, were synthesized by exploiting a unique two-step integrated microfluidic synthesis scheme in a continuous-flow mode. The synthesized MOF crystals were characterized by X-ray diffraction, scanning electron microscopy, and BET surface area measurements. In comparison with bare MOF-5, MOF-5@diCH3-MOF-5 showed enhanced structural stability in the presence of moisture, and the catalytic performance of Fe3O4@ZIF-8 was examined using Knoevenagel condensation as a probe reaction. The microfluidic strategy allowed continuous fabrication of high-quality MOF crystals and composites exhibiting distinct morphological characteristics in a time-efficient manner and represents a viable alternative to the time-consuming and multistep MOF synthesis processes.

  8. Synthesis for Structure Rewriting Systems

    NASA Astrophysics Data System (ADS)

    Kaiser, Łukasz

    The description of a single state of a modelled system is often complex in practice, but few procedures for synthesis address this problem in depth. We study systems in which a state is described by an arbitrary finite structure, and changes of the state are represented by structure rewriting rules, a generalisation of term and graph rewriting. Both the environment and the controller are allowed to change the structure in this way, and the question we ask is how a strategy for the controller that ensures a given property can be synthesised.

  9. Synthesis, characterisation and applications of coiled carbon nanotubes.

    PubMed

    Hanus, Monica J; Harris, Andrew T

    2010-04-01

    Coiled carbon nanotubes are helical carbon structures formed when heptagonal and pentagonal rings are inserted into the hexagonal backbone of a 'straight' nanotube. Coiled carbon nanotubes have been reported with both regular and irregular helical structures. In this work the structure, growth mechanism(s), synthesis, properties and potential applications of coiled carbon nanotubes are reviewed. Published data suggests that coiled carbon nanotube synthesis occurs due to nonuniform extrusion of carbon from a catalyst surface. To date, coiled carbon nanotubes have been synthesised using catalyst modification techniques including: (i) the addition of S or P containing compounds during synthesis; (ii) the use of binary or ternary metal catalysts; (iii) the use of microwaves to create a local temperature gradient around individual catalyst particles and; (iv) the use of pH control during catalyst preparation. In most instances coiled carbon nanotubes are produced as a by-product; high yield and/or large-scale synthesis of coiled carbon nanotubes remains problematic. The qualitative analysis of coiled carbon nanotubes is currently hindered by the absence of specific characterisation data in the literature, e.g., oxidation profiles measured by thermogravimetric analysis and Raman spectra of pure coiled carbon nanotube samples.

  10. Regulation of Staphylococcal Penicillinase Synthesis

    PubMed Central

    Imsande, John; Zyskind, Judith W.; Mile, Imre

    1972-01-01

    5-Methyl tryptophan was found to be an efficient inducer of penicillinase synthesis in Staphylococcus aureus. Addition of actinomycin D or tryptophan to the culture medium shuts off the 5-methyl tryptophan-induced synthesis of penicillinase with an apparent half-life of approximately 1 to 2 min, respectively. Hence, in the induction of penicillinase synthesis, 5-methyl tryptophan seems to function as a structural analogue of penicillin rather than by becoming incorporated in proteins and thereby creating faulty penicillinase repressor or antirepressor. This conclusion is supported by similarities in the structures of the two compounds as revealed by solid atomic models. The fact that S. aureus exposed to 14C-penicillin in the absence of protein synthesis failed to synthesize penicillinase at an increased level when cell growth was resumed strongly suggests that a protein involved in the regulation of penicillinase synthesis must be synthesized in the presence of the penicillinase inducer. In turn, this observation suggests that the penicillinase inducer promotes penicillinase synthesis by directing the penicillinase regulatory protein (i.e., the penicillinase antirepressor) to acquire a different conformation when it is synthesized in the presence of the penicillinase inducer. A working model for the regulation of penicillinase synthesis based on these and other data has been constructed and is presented. Images PMID:4333374

  11. The dynamics of coiled bodies in the nucleus of adenovirus-infected cells.

    PubMed Central

    Rebelo, L; Almeida, F; Ramos, C; Bohmann, K; Lamond, A I; Carmo-Fonseca, M

    1996-01-01

    The coiled body is a specific intranuclear structure of unknown function that is enriched in splicing small nuclear ribonucleoproteins (snRNPs). Because adenoviruses make use of the host cell-splicing machinery and subvert the normal subnuclear organization, we initially decided to investigate the effect of adenovirus infection on the coiled body. The results indicate that adenovirus infection induces the disassembly of coiled bodies and that this effect is probably secondary to the block of host protein synthesis induced by the virus. Furthermore, coiled bodies are shown to be very labile structures, with a half-life of approximately 2 h after treatment of HeLa cells with protein synthesis inhibitors. After blocking of protein synthesis, p80 coilin was detected in numerous microfoci that do not concentrate snRNP. These structures may represent precursor forms of the coiled body, which goes through a rapid cycle of assembly/disassembly in the nucleus and requires ongoing protein synthesis to reassemble. Images PMID:8862526

  12. Semiconductor nanowires: A platform for nanoscience and nanotechnology

    PubMed Central

    Lieber, Charles M.

    2012-01-01

    Advances in nanoscience and nanotechnology critically depend on the development of nanostructures whose properties are controlled during synthesis. We focus on this critical concept using semiconductor nanowires, which provide the capability through design and rational synthesis to realize unprecedented structural and functional complexity in building blocks as a platform material. First, a brief review of the synthesis of complex modulated nanowires in which rational design and synthesis can be used to precisely control composition, structure, and, most recently, structural topology is discussed. Second, the unique functional characteristics emerging from our exquisite control of nanowire materials are illustrated using several selected examples from nanoelectronics and nano-enabled energy. Finally, the remarkable power of nanowire building blocks is further highlighted through their capability to create unprecedented, active electronic interfaces with biological systems. Recent work pushing the limits of both multiplexed extracellular recording at the single-cell level and the first examples of intracellular recording is described, as well as the prospects for truly blurring the distinction between nonliving nanoelectronic and living biological systems. PMID:22707850

  13. Reverse transcription of phage RNA and its fragment directed by synthetic heteropolymeric primers

    PubMed Central

    Frolova, L. Yu.; Metelyev, V. G.; Ratmanova, K. I.; Smirnov, V. D.; Shabarova, Z. A.; Prokofyev, M. A.; Berzin, V. M.; Jansone, I. V.; Gren, E. J.; Kisselev, L. L.

    1977-01-01

    DNA synthesis catalysed by RNA-directed DNA-polymerase (reverse transcriptase) was found to proceed on the RNA template of an MS2 phage in the presence of heteropolymeric synthetic octa- and nonadeoxyribonucleotide primers complementary to the intercistronic region (coat protein binding site) and the region of the coat protein cistron, respectively. The product of synthesis consists of discrete DNA fractions of different length, including transcripts longer than 1,000 nucleotides. The coat protein inhibits DNA synthesis if it is initiated at its binding site, but has no effect on DNA synthesis initiated at the coat protein cistron. It has been suggested that, in this system, the initiation of DNA synthesis by synthetic primers is topographically specific. The MS2 coat protein binding site (an RNA fragment of 59 nucleotides) serves as a template for polydeoxyribonucleotide synthesis in the presence of octanucleotide primer and reverse transcriptase. The product of synthesis is homogenous and its length corresponds to the length of the template. The effective and complete copying of the fragment having a distinct secondary structure proves that the secondary structure does not interfere, in principle, with RNA being a template in the system of reverse transcription. PMID:71713

  14. A simple, rapid, high-fidelity and cost-effective PCR-based two-step DNA synthesis method for long gene sequences.

    PubMed

    Xiong, Ai-Sheng; Yao, Quan-Hong; Peng, Ri-He; Li, Xian; Fan, Hui-Qin; Cheng, Zong-Ming; Li, Yi

    2004-07-07

    Chemical synthesis of DNA sequences provides a powerful tool for modifying genes and for studying gene function, structure and expression. Here, we report a simple, high-fidelity and cost-effective PCR-based two-step DNA synthesis (PTDS) method for synthesis of long segments of DNA. The method involves two steps. (i) Synthesis of individual fragments of the DNA of interest: ten to twelve 60mer oligonucleotides with 20 bp overlap are mixed and a PCR reaction is carried out with high-fidelity DNA polymerase Pfu to produce DNA fragments that are approximately 500 bp in length. (ii) Synthesis of the entire sequence of the DNA of interest: five to ten PCR products from the first step are combined and used as the template for a second PCR reaction using high-fidelity DNA polymerase pyrobest, with the two outermost oligonucleotides as primers. Compared with the previously published methods, the PTDS method is rapid (5-7 days) and suitable for synthesizing long segments of DNA (5-6 kb) with high G + C contents, repetitive sequences or complex secondary structures. Thus, the PTDS method provides an alternative tool for synthesizing and assembling long genes with complex structures. Using the newly developed PTDS method, we have successfully obtained several genes of interest with sizes ranging from 1.0 to 5.4 kb.

  15. Effect of Synthesis Parameter on Crystal Structures and Magnetic Properties of Magnesium Nickel Ferrite (Mg0.5Ni0.5Fe2O4) Nanoparticles

    NASA Astrophysics Data System (ADS)

    Maulia, R.; Putra, R. A.; Suharyadi, E.

    2017-05-01

    Mg0.5Ni0.5Fe2O4 nanoparticles have been successfully synthesized by using co-precipitation method and varying the synthesis parameter, i.e. synthesis temperature and NaOH concentration. X-ray Diffraction (XRD) pattern showed that nanoparticles have cubic spinel structures with an additional phase of γ-Fe2O3 and particle size varies within the range of 4.3 - 6.7 nm. This variation is due to the effect of various synthesis parameters. Transmission Electron Microscopy (TEM) image showed that the nanoparticles exhibited agglomeration. The observed diffraction ring from selected area electron diffraction showed that the sample was polycrystalline and confirmed the peak appearing in XRD. The coercivities showed an increasing trend with an increase in particle size from 44.7 Oe to 49.6 Oe for variation of NaOH concentration, and a decreasing trend with an increase in particle size from 46.8 to 45.1 Oe for variation of synthesis temperature. The maximum magnetization showed an increasing trend with an increase in the ferrite phase from 3.7 emu/g to 5.4 emu/g possessed in the sample with variations on NaOH concentration. The maximum magnetization for the sample with variations on synthesis temperature varied from 4.4 emu/g to 5.7 emu/g due to its crystal structures.

  16. What Is Linguistics? ERIC Digest. [Revised].

    ERIC Educational Resources Information Center

    ERIC Clearinghouse on Languages and Linguistics, Washington, DC.

    Linguistics is the study of language, as contrasted with knowledge of a specific language. Formal linguistics is the study of the structures and processes of language, or how it works and is organized. Different approaches to formal linguistics include traditional or prescriptive, structural, and generative or transformational perspectives. Formal…

  17. 78 FR 18535 - Respirator Certification Fees

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-27

    ...) proposes to revise the fee structure currently used by the National Institute for Occupational Safety and... performance through product quality audits; (10) replacing testing equipment; and (11) providing and... structure for certifying respirators were codified by HHS in 42 CFR part 84, which was published in June of...

  18. Robust, nonlinear, high angle-of-attack control design for a supermaneuverable vehicle

    NASA Technical Reports Server (NTRS)

    Adams, Richard J.

    1993-01-01

    High angle-of-attack flight control laws are developed for a supermaneuverable fighter aircraft. The methods of dynamic inversion and structured singular value synthesis are combined into an approach which addresses both the nonlinearity and robustness problems of flight at extreme operating conditions. The primary purpose of the dynamic inversion control elements is to linearize the vehicle response across the flight envelope. Structured singular value synthesis is used to design a dynamic controller which provides robust tracking to pilot commands. The resulting control system achieves desired flying qualities and guarantees a large margin of robustness to uncertainties for high angle-of-attack flight conditions. The results of linear simulation and structured singular value stability analysis are presented to demonstrate satisfaction of the design criteria. High fidelity nonlinear simulation results show that the combined dynamics inversion/structured singular value synthesis control law achieves a high level of performance in a realistic environment.

  19. Synthesis of gold structures by gold-binding peptide governed by concentration of gold ion and peptide.

    PubMed

    Kim, Jungok; Kim, Dong-Hun; Lee, Sylvia J; Rheem, Youngwoo; Myung, Nosang V; Hur, Hor-Gil

    2016-08-01

    Although biological synthesis methods for the production of gold structures by microorganisms, plant extracts, proteins, and peptide have recently been introduced, there have been few reports pertaining to controlling their size and morphology. The gold ion and peptide concentrations affected on the size and uniformity of gold plates by a gold-binding peptide Midas-11. The higher concentration of gold ions produced a larger size of gold structures reached 125.5 μm, but an increased amount of Midas-11 produced a smaller size of gold platelets and increased the yield percentage of polygonal gold particles rather than platelets. The mechanisms governing factors controlling the production of gold structures were primarily related to nucleation and growth. These results indicate that the synthesis of gold architectures can be controlled by newly isolated and substituted peptides under different reaction conditions.

  20. A revised MRCI-algorithm. I. Efficient combination of spin adaptation with individual configuration selection coupled to an effective valence-shell Hamiltonian

    NASA Astrophysics Data System (ADS)

    Strodel, Paul; Tavan, Paul

    2002-09-01

    We present a revised multi-reference configuration interaction (MRCI) algorithm for balanced and efficient calculation of electronic excitations in molecules. The revision takes up an earlier method, which had been designed for flexible, state-specific, and individual selection (IS) of MRCI expansions, included perturbational corrections (PERT), and used the spin-coupled hole-particle formalism of Tavan and Schulten (1980) for matrix-element evaluation. It removes the deficiencies of this method by introducing tree structures, which code the CI bases and allow us to efficiently exploit the sparseness of the Hamiltonian matrices. The algorithmic complexity is shown to be optimal for IS/MRCI applications. The revised IS/MRCI/PERT module is combined with the effective valence shell Hamiltonian OM2 suggested by Weber and Thiel (2000). This coupling serves the purpose of making excited state surfaces of organic dye molecules accessible to relatively cheap and sufficiently precise descriptions.

  1. Epistemic beliefs of non-STEM majors regarding the nature of science: Where they are and what we can do

    NASA Astrophysics Data System (ADS)

    Willoughby, Shannon D.; Johnson, Keith

    2017-06-01

    Students enrolled in introductory astronomy at a mid-sized land grant institution were surveyed at the start and end of each semester for three years regarding their epistemic beliefs about the physical sciences. After collecting data for two years in the control (baseline) course, the course was revised to include regular discussions of the nature of science, practice identifying pseudoscientific claims, and practice with metacognition. Survey data on epistemic beliefs were collected for one more academic year after the course was revised. This work details how the course was structured during the baseline and revised portions of the study. Data from both portions of the study are analyzed as a whole as well as broken down by gender. Negative trends seen in the baseline data are mostly eradicated in the revised portion of the course. The data analysis motivates a discussion of why including content regarding the nature of science should be integrated in classes geared toward non-science majors.

  2. The development and validation of the Physical Appearance Comparison Scale-Revised (PACS-R).

    PubMed

    Schaefer, Lauren M; Thompson, J Kevin

    2014-04-01

    The Physical Appearance Comparison Scale (PACS; Thompson, Heinberg, & Tantleff, 1991) was revised to assess appearance comparisons relevant to women and men in a wide variety of contexts. The revised scale (Physical Appearance Comparison Scale-Revised, PACS-R) was administered to 1176 college females. In Study 1, exploratory factor analysis and parallel analysis using one half of the sample suggested a single factor structure for the PACS-R. Study 2 utilized the remaining half of the sample to conduct confirmatory factor analysis, item analysis, and to examine the convergent validity of the scale. These analyses resulted in an 11-item measure that demonstrated excellent internal consistency and convergent validity with measures of body satisfaction, eating pathology, sociocultural influences on appearance, and self-esteem. Regression analyses demonstrated the utility of the PACS-R in predicting body satisfaction and eating pathology. Overall, results indicate that the PACS-R is a reliable and valid tool for assessing appearance comparison tendencies in women. Copyright © 2014. Published by Elsevier Ltd.

  3. MARIKA - A model revision system using qualitative analysis of simulations. [of human orientation system

    NASA Technical Reports Server (NTRS)

    Groleau, Nicolas; Frainier, Richard; Colombano, Silvano; Hazelton, Lyman; Szolovits, Peter

    1993-01-01

    This paper describes portions of a novel system called MARIKA (Model Analysis and Revision of Implicit Key Assumptions) to automatically revise a model of the normal human orientation system. The revision is based on analysis of discrepancies between experimental results and computer simulations. The discrepancies are calculated from qualitative analysis of quantitative simulations. The experimental and simulated time series are first discretized in time segments. Each segment is then approximated by linear combinations of simple shapes. The domain theory and knowledge are represented as a constraint network. Incompatibilities detected during constraint propagation within the network yield both parameter and structural model alterations. Interestingly, MARIKA diagnosed a data set from the Massachusetts Eye and Ear Infirmary Vestibular Laboratory as abnormal though the data was tagged as normal. Published results from other laboratories confirmed the finding. These encouraging results could lead to a useful clinical vestibular tool and to a scientific discovery system for space vestibular adaptation.

  4. Self-assembled hierarchically structured organic-inorganic composite systems.

    PubMed

    Tritschler, Ulrich; Cölfen, Helmut

    2016-05-13

    Designing bio-inspired, multifunctional organic-inorganic composite materials is one of the most popular current research objectives. Due to the high complexity of biocomposite structures found in nacre and bone, for example, a one-pot scalable and versatile synthesis approach addressing structural key features of biominerals and affording bio-inspired, multifunctional organic-inorganic composites with advanced physical properties is highly challenging. This article reviews recent progress in synthesizing organic-inorganic composite materials via various self-assembly techniques and in this context highlights a recently developed bio-inspired synthesis concept for the fabrication of hierarchically structured, organic-inorganic composite materials. This one-step self-organization concept based on simultaneous liquid crystal formation of anisotropic inorganic nanoparticles and a functional liquid crystalline polymer turned out to be simple, fast, scalable and versatile, leading to various (multi-)functional composite materials, which exhibit hierarchical structuring over several length scales. Consequently, this synthesis approach is relevant for further progress and scientific breakthrough in the research field of bio-inspired and biomimetic materials.

  5. OPTICON: Pro-Matlab software for large order controlled structure design

    NASA Technical Reports Server (NTRS)

    Peterson, Lee D.

    1989-01-01

    A software package for large order controlled structure design is described and demonstrated. The primary program, called OPTICAN, uses both Pro-Matlab M-file routines and selected compiled FORTRAN routines linked into the Pro-Matlab structure. The program accepts structural model information in the form of state-space matrices and performs three basic design functions on the model: (1) open loop analyses; (2) closed loop reduced order controller synthesis; and (3) closed loop stability and performance assessment. The current controller synthesis methods which were implemented in this software are based on the Generalized Linear Quadratic Gaussian theory of Bernstein. In particular, a reduced order Optimal Projection synthesis algorithm based on a homotopy solution method was successfully applied to an experimental truss structure using a 58-state dynamic model. These results are presented and discussed. Current plans to expand the practical size of the design model to several hundred states and the intention to interface Pro-Matlab to a supercomputing environment are discussed.

  6. A modified approach to 2-(N-aryl)-1,3-oxazoles: application to the synthesis of the IMPDH inhibitor BMS-337197 and analogues.

    PubMed

    Dhar, T G Murali; Guo, Junqing; Shen, Zhongqi; Pitts, William J; Gu, Henry H; Chen, Bang-Chi; Zhao, Rulin; Bednarz, Mark S; Iwanowicz, Edwin J

    2002-06-13

    [structure: see text] A modified approach to the synthesis of 2-(N-aryl)-1,3-oxazoles, employing an optimized iminophosphorane/heterocumulene-mediated methodology, and its application to the synthesis of BMS-337197, a potent inhibitor of IMPDH, are described.

  7. A Research Synthesis of the Evaluation Capacity Building Literature

    ERIC Educational Resources Information Center

    Labin, Susan N.; Duffy, Jennifer L.; Meyers, Duncan C.; Wandersman, Abraham; Lesesne, Catherine A.

    2012-01-01

    The continuously growing demand for program results has produced an increased need for evaluation capacity building (ECB). The "Integrative ECB Model" was developed to integrate concepts from existing ECB theory literature and to structure a synthesis of the empirical ECB literature. The study used a broad-based research synthesis method with…

  8. TiO{sub 2} synthesized by microwave assisted solvothermal method: Experimental and theoretical evaluation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Moura, K.F.; Maul, J.; Albuquerque, A.R.

    2014-02-15

    In this study, a microwave assisted solvothermal method was used to synthesize TiO{sub 2} with anatase structure. The synthesis was done using Ti (IV) isopropoxide and ethanol without templates or alkalinizing agents. Changes in structural features were observed with increasing time of synthesis and evaluated using periodic quantum chemical calculations. The anatase phase was obtained after only 1 min of reaction besides a small amount of brookite phase. Experimental Raman spectra are in accordance with the theoretical one. Micrometric spheres constituted by nanometric particles were obtained for synthesis from 1 to 30 min, while spheres and sticks were observed aftermore » 60 min. - Graphical abstract: FE-SEM images of anatase obtained with different periods of synthesis associated with the order–disorder degree. Display Omitted - Highlights: • Anatase microspheres were obtained by the microwave assisted hydrothermal method. • Only ethanol and titanium isopropoxide were used as precursors during the synthesis. • Raman spectra and XRD patterns were compared with quantum chemical calculations. • Time of synthesis increased the short-range disorder in one direction and decreased in another.« less

  9. Advances in engineering science, volume 2

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Papers are presented dealing with structural dynamics; structural synthesis; and the nonlinear analysis of structures, structural members, and composite structures and materials. Applications of mathematics and computer science are included.

  10. Enzymatic Synthesis of Self-assembled Dicer Substrate RNA Nanostructures for Programmable Gene Silencing.

    PubMed

    Jang, Bora; Kim, Boyoung; Kim, Hyunsook; Kwon, Hyokyoung; Kim, Minjeong; Seo, Yunmi; Colas, Marion; Jeong, Hansaem; Jeong, Eun Hye; Lee, Kyuri; Lee, Hyukjin

    2018-06-08

    Enzymatic synthesis of RNA nanostructures is achieved by isothermal rolling circle transcription (RCT). Each arm of RNA nanostructures provides a functional role of Dicer substrate RNA inducing sequence specific RNA interference (RNAi). Three different RNAi sequences (GFP, RFP, and BFP) are incorporated within the three-arm junction RNA nanostructures (Y-RNA). The template and helper DNA strands are designed for the large-scale in vitro synthesis of RNA strands to prepare self-assembled Y-RNA. Interestingly, Dicer processing of Y-RNA is highly influenced by its physical structure and different gene silencing activity is achieved depending on its arm length and overhang. In addition, enzymatic synthesis allows the preparation of various Y-RNA structures using a single DNA template offering on demand regulation of multiple target genes.

  11. Effects of Gold Salt Speciation and Structure of Human and Bovine Serum Albumin on the Synthesis and Stability of Gold Nanostructures

    NASA Astrophysics Data System (ADS)

    Miranda, Érica; Tofanello, Aryane; Brito, Adrianne; Lopes, David; Giacomelli, Fernando; Albuquerque, Lindomar; Costa, Fanny; Ferreira, Fabio; Araujo-Chaves, Juliana; de Castro, Carlos; Nantes, Iseli

    2016-03-01

    The present study aimed to investigate the influence of albumin structure and gold speciation on the synthesis of gold nanoparticles (GNPs). The strategy of synthesis was the addition of HAuCl4 solutions at different pH values (3-12) to solutions of human and bovine serum albumins (HSA and BSA) at the same corresponding pH values. Different pH values influence the GNP synthesis due to gold speciation. Besides the inherent effect of pH on the native structure of albumins, the use N-ethylmaleimide (NEM)-treated and heat-denaturated forms of HSA and BSA provided additional insights about the influence of protein structure, net charge, and thiol group approachability on the GNP synthesis. NEM treatment, heating, and the extreme values of pH promoted loss of the native albumin structure. The formation of GNPs indicated by the appearance of surface plasmon resonance (SPR) bands became detectable from fifteen days of the synthesis processes that were carried out with native, NEM-treated and heat-denaturated forms of HSA and BSA, exclusively at pH 6 and 7. After two months of incubation, SPR band was also detected for all synthesis carried out at pH 8.0. The mean values of the hydrodynamic radius (RH) were 24 and 34 nm for GNPs synthesized with native HSA and BSA, respectively. X-ray diffraction (XRD) revealed crystallites of 13 nm. RH, XRD, and zeta potential values were consistent with GNP capping by the albumins. However, the GNPs produced with NEM-treated and heat-denaturated albumins exhibited loss of protein capping by lowering the ionic strength. This result suggests a significant contribution of non-electrostatic interactions of albumins with the GNP surface, in these conditions. The denaturation of proteins exposes hydrophobic groups to the solvent, and these groups could interact with the gold surface. In these conditions, the thiol blockage or oxidation, the latter probably favored upon heating, impaired the formation of a stable capping by thiol coordination with the gold surface. Therefore, the cysteine side chain of albumins is important for the colloidal stabilization of GNPs rather than as the reducing agent for the synthesis. Despite the presence of more reactive gold species at more acidic pH values, i.e., below

  12. Two chain gallium fluorodiphosphates: synthesis, structure solution, and their transient presence during the hydrothermal crystallisation of a microporous gallium fluorophosphate.

    PubMed

    Millange, Franck; Walton, Richard I; Guillou, Nathalie; Loiseau, Thierry; O'Hare, Dermot; Férey, Gérard

    2002-04-21

    Two novel gallium fluorodiphosphates have been isolated and their structures solved ab initio from powder X-ray diffraction data; the materials readily interconvert under hydrothermal conditions, and are metastable with respect to an open-framework zeolitic gallium fluorophosphate, during the synthesis of which they are present as transient intermediates.

  13. New Synthesis Of Poly(1,3,4-Oxadiazoles)

    NASA Technical Reports Server (NTRS)

    Connell, John W.; Hergenrother, Paul M.; Wolf, Peter

    1992-01-01

    Synthesis via aromatic nucleophilic displacement yields new high-molecular-weight polymers. Polymers exhibited good mechanical and thermal properties. Synthetic route provided high-molecular-weight POX of new chemical structure, potentially more economical. Availability of large variety of activated aromatic dihalides, facilitates variation of chemical structures. Exhibit properties making them useful as films. Also useful in coatings, adhesives, moldings, and composites.

  14. A template-free solvent-mediated synthesis of high surface area boron nitride nanosheets for aerobic oxidative desulfurization

    DOE PAGES

    Wu, Peiwen; Zhu, Wenshuai; Chao, Yanhong; ...

    2015-10-16

    Hexagonal boron nitride nanosheets (h-BNNs) with rather high specific surface area (SSA) are important two-dimensional layer-structured materials. Here in this study, a solvent-mediated synthesis of h-BNNs revealed a template-free lattice plane control strategy that induced high SSA nanoporous structured h-BNNs with outstanding aerobic oxidative desulfurization performance.

  15. Organization of genes required for the oxidation of methanol to formaldehyde in three type II methylotrophs

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bastien, C.; Machlin, S.; Zhang, Y.

    Restriction maps of genes required for the synthesis of active methanol dehydrogenase in Methylobacterium organophilum XX and Methylobacterium sp. strain AM1 have been completed and compared. In these two species of pink-pigmented, type II methylotrophs, 15 genes were identified that were required for the expression of methanol dehydrogenase activity. None of these genes were required for the synthesis of the prosthetic group of methanol dehydrogenase, pyrroloquinoline quinone. The structural gene required for the synthesis of cytochrome c{sub L}, an electron acceptor uniquely required for methanol dehydrogenase, and the genes encoding small basic peptides that copurified with methanol dehydrogenases were closelymore » linked to the methanol dehydrogenase structural genes. A cloned 22-kilobase DNA insert from Methylsporovibrio methanica 81Z, an obligate type II methanotroph, complemented mutants that contained lesions in four genes closely linked to the methanol dehydrogenase structural genes. The methanol dehydrogenase and cytochrome c{sub L} structural genes were found to be transcribed independently in M. organophilum XX. Only two of the genes required for methanol dehydrogenase synthesis in this bacterium were found to be cotranscribed.« less

  16. Recent and Future Enhancements in NDI for Aircraft Structures

    DTIC Science & Technology

    2015-11-30

    accomplish NDI of aircraft structure. This includes improved eddy current probes, improved eddy current instrumentation, as well as other...Aircraft Structures,” which is currently in Revision C [8]. The document divides various inspection methods, such as eddy current and fluorescent...efforts at AFRL to address technology shortfalls include improved eddy current probes, improved eddy current instrumentation, as well as other

  17. Recent and Future Enhancements in NDI for Aircraft Structures (Postprint)

    DTIC Science & Technology

    2015-11-30

    accomplish NDI of aircraft structure. This includes improved eddy current probes, improved eddy current instrumentation, as well as other...Aircraft Structures,” which is currently in Revision C [8]. The document divides various inspection methods, such as eddy current and fluorescent...efforts at AFRL to address technology shortfalls include improved eddy current probes, improved eddy current instrumentation, as well as other

  18. Recent and Future Enhancements in NDI for Aircraft Structures (Postprint)

    DTIC Science & Technology

    2015-11-01

    accomplish NDI of aircraft structure. This includes improved eddy current probes, improved eddy current instrumentation, as well as other...Aircraft Structures,” which is currently in Revision C [8]. The document divides various inspection methods, such as eddy current and fluorescent...efforts at AFRL to address technology shortfalls include improved eddy current probes, improved eddy current instrumentation, as well as other

  19. Recent and Future Enhancements in NDI for Aircraft Structures (POSTPRINT)

    DTIC Science & Technology

    2015-11-16

    accomplish NDI of aircraft structure. This includes improved eddy current probes, improved eddy current instrumentation, as well as other...Aircraft Structures,” which is currently in Revision C [8]. The document divides various inspection methods, such as eddy current and fluorescent...efforts at AFRL to address technology shortfalls include improved eddy current probes, improved eddy current instrumentation, as well as other

  20. Processing structure in language and music: a case for shared reliance on cognitive control.

    PubMed

    Slevc, L Robert; Okada, Brooke M

    2015-06-01

    The relationship between structural processing in music and language has received increasing interest in the past several years, spurred by the influential Shared Syntactic Integration Resource Hypothesis (SSIRH; Patel, Nature Neuroscience, 6, 674-681, 2003). According to this resource-sharing framework, music and language rely on separable syntactic representations but recruit shared cognitive resources to integrate these representations into evolving structures. The SSIRH is supported by findings of interactions between structural manipulations in music and language. However, other recent evidence suggests that such interactions also can arise with nonstructural manipulations, and some recent neuroimaging studies report largely nonoverlapping neural regions involved in processing musical and linguistic structure. These conflicting results raise the question of exactly what shared (and distinct) resources underlie musical and linguistic structural processing. This paper suggests that one shared resource is prefrontal cortical mechanisms of cognitive control, which are recruited to detect and resolve conflict that occurs when expectations are violated and interpretations must be revised. By this account, musical processing involves not just the incremental processing and integration of musical elements as they occur, but also the incremental generation of musical predictions and expectations, which must sometimes be overridden and revised in light of evolving musical input.

  1. Interference-Free and Interference-Dominated Photoionization: Synthesis of Ultrashort and Coherent Single-Electron Wave Packets

    NASA Astrophysics Data System (ADS)

    Cajiao Vélez, F.; Kamiński, J. Z.; Krajewska, K.

    2018-04-01

    Ionization of hydrogen-like ions driven by intense, short, and circularly-polarized laser pulses is considered under the scope of the relativistic strong-field approximation. We show that the energy spectra of photoelectrons can exhibit two types of structures, i.e., interference-dominated or interference-free ones. These structures are analyzed in connection to the time-dependent ponderomotive energy of electrons in the laser field. A possibility of synthesis of ultrashort single-electron pulses from those structures is also investigated.

  2. Inhibitors of Fatty Acid Synthase for Prostate Cancer. Revision

    DTIC Science & Technology

    2013-05-01

    the fact that is recognized saturated fat as a substrate. This report summarizes the the immense amount of structure-activity-relationships for new...indazole ring of structure 3a; and coupling of various aldehydes and ,- unsaturated ethers to the 5 position of the quinine under acidic

  3. A Survey of Structural Linguistics.

    ERIC Educational Resources Information Center

    Lepschy, Giulio C.

    This book, a revised and expanded English version of the author's Italian work "La Linguistica strutturale" (1961), is a survey of the main trends in structural linguistics intended not only for the linguist but for specialists in other fields and the general reader as well. The initial chapter, "Introductory Notions," discusses general linguistic…

  4. Identifying Psychopathy Subtypes on the Basis of Personality Structure

    ERIC Educational Resources Information Center

    Hicks, Brian M.; Markon, Kristian E.; Patrick, Christopher J.; Krueger, Robert F.; Newman, Joseph P.

    2004-01-01

    The authors used model-based cluster analysis to identify subtypes of criminal psychopaths on the basis of differences in personality structure. Participants included 96 male prisoners diagnosed as psychopathic, using the Psychopathy Checklist Revised (PCL-R; R. D. Hare, 1991). Personality was assessed using the brief form of the Multidimensional…

  5. Variable dimensionality in the uranium fluoride/2-methyl-piperazine system: Synthesis and structures of UFO-5, -6, and -7; Zero-, one-, and two-dimensional materials with unprecedented topologies

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Francis, R.J.; Halasyamani, P.S.; Bee, J.S.

    Recently, low temperature (T < 300 C) hydrothermal reactions of inorganic precursors in the presence of organic cations have proven highly productive for the synthesis of novel solid-state materials. Interest in these materials is driven by the astonishingly diverse range of structures produced, as well as by their many potential materials chemistry applications. This report describes the high yield, phase pure hydrothermal syntheses of three new uranium fluoride phases with unprecedented structure types. Through the systematic control of the synthesis conditions the authors have successfully controlled the architecture and dimensionality of the phase formed and selectively synthesized novel zero-, one-,more » and two-dimensional materials.« less

  6. Synthesis and structural properties of Ba(1-x)LaxTiO3 perovskite nanoparticles fabricated by solvothermal synthesis route

    NASA Astrophysics Data System (ADS)

    Puli, Venkata Sreenivas; Adireddy, Shiva; Elupula, Ravinder; Molugu, Sudheer; Shipman, Josh; Chrisey, Douglas B.

    2017-05-01

    We report the successful synthesis and structural characterization of barium lanthanum titanate Ba(1-x)LaxTiO3 (x=0.003,0.006,0.010) nanoparticles. The colloidal nanoparticles were prepared with high yield by a solvothermal method at temperatures as low as 150°C for 24h. The as-prepared nanopowders were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), and Raman spectroscopy. The XRD studies revealed pseudo-cubic crystalline structure, with no impurity phases at room temperature. However ferroelectric tetragonal modes were clearly observed using Raman spectroscopy measurements. From TEM measurements, uniformly sized BLT nanoparticles were observed. Selected area diffraction TEM images revealed polycrystalline perovskite ring patterns, identified as corresponding to the tetragonal phase.

  7. Influence of Chemical Conditions on the Nanoporous Structure of Silicate Aerogels

    PubMed Central

    Sinkó, Katalin

    2010-01-01

    Silica or various silicate aerogels can be characterized by highly porous, open cell, low density structures. The synthesis parameters influence the three-dimensional porous structures by modifying the kinetics and mechanism of hydrolysis and condensation processes. Numerous investigations have shown that the structure of porous materials can be tailored by variations in synthesis conditions (e.g., the type of precursors, catalyst, and surfactants; the ratio of water/precursor; the concentrations; the medium pH; and the solvent). The objectives of this review are to summarize and elucidate the effects of chemical conditions on the nanoporous structure of sol-gel derived silicate aerogels.

  8. Design and synthesis of diverse functional kinked nanowire structures for nanoelectronic bioprobes.

    PubMed

    Xu, Lin; Jiang, Zhe; Qing, Quan; Mai, Liqiang; Zhang, Qingjie; Lieber, Charles M

    2013-02-13

    Functional kinked nanowires (KNWs) represent a new class of nanowire building blocks, in which functional devices, for example, nanoscale field-effect transistors (nanoFETs), are encoded in geometrically controlled nanowire superstructures during synthesis. The bottom-up control of both structure and function of KNWs enables construction of spatially isolated point-like nanoelectronic probes that are especially useful for monitoring biological systems where finely tuned feature size and structure are highly desired. Here we present three new types of functional KNWs including (1) the zero-degree KNW structures with two parallel heavily doped arms of U-shaped structures with a nanoFET at the tip of the "U", (2) series multiplexed functional KNW integrating multi-nanoFETs along the arm and at the tips of V-shaped structures, and (3) parallel multiplexed KNWs integrating nanoFETs at the two tips of W-shaped structures. First, U-shaped KNWs were synthesized with separations as small as 650 nm between the parallel arms and used to fabricate three-dimensional nanoFET probes at least 3 times smaller than previous V-shaped designs. In addition, multiple nanoFETs were encoded during synthesis in one of the arms/tip of V-shaped and distinct arms/tips of W-shaped KNWs. These new multiplexed KNW structures were structurally verified by optical and electron microscopy of dopant-selective etched samples and electrically characterized using scanning gate microscopy and transport measurements. The facile design and bottom-up synthesis of these diverse functional KNWs provides a growing toolbox of building blocks for fabricating highly compact and multiplexed three-dimensional nanoprobes for applications in life sciences, including intracellular and deep tissue/cell recordings.

  9. Agreement Between the JCDCG, Revised NCEP-ATPIII, and IDF Definitions of Metabolic Syndrome in a Northwestern Chinese Population.

    PubMed

    Sun, Fei; Gao, Bin; Wang, Li; Xing, Ying; Ming, Jie; Zhou, Jie; Fu, Jianfang; Li, Xiaomiao; Xu, Shaoyong; Liu, Guocai; Ji, Qiuhe

    2018-05-28

    The Joint Committee for Developing Chinese Guidelines (JCDCG) introduced the Chinese definition for metabolic syndrome (MS), which has been verified in southern Chinese people but not in northwestern Chinese people. We evaluated the MS definition proposed by the JCDCG in a northwestern Chinese population, in comparison with those of the revised National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATPIII) and the International Diabetes Federation (IDF). This population-based cross-sectional study was a part of the China National Diabetes and Metabolic Disorders Study conducted in Shaanxi province. We included 3243 participants aged ≥ 20 years. The age-adjusted MS prevalence was assessed per the 2007 Chinese population structure. The agreement between different definitions was assessed by the kappa statistic. The standardized prevalence of JCDCG-MS, revised ATPIII-MS, and IDF-MS was 22.4%, 29.4%, and 24.9%, respectively. Among women, the agreement of the JCDCG definition with the revised ATPIII and the IDF definition was not good (κ = 0.599 and 0.601, respectively); 54.6% of the revised ATPIII-MS and 56% of the IDF-MS were defined as MS according to the JCDCG definition. Among men, the agreement of JCDCG definition with the revised ATPIII and IDF definitions was very good (κ = 0.863) and substantial (κ = 0.741), respectively. The agreement of the JCDCG definition with the revised ATPIII and IDF definitions was insufficient in women. Compared with the other two definitions, the JCDCG definition underestimates MS prevalence in northwestern women.

  10. Reliability and Validity of the Sexual Pressure Scale for Women-Revised

    PubMed Central

    Jones, Rachel; Gulick, Elsie

    2008-01-01

    Sexual pressure among young urban women represents adherence to gender stereotypical expectations to engage in sex. Revision of the original 5-factor Sexual Pressure Scale was undertaken in two studies to improve reliabilities in two of the five factors. In Study 1 the reliability of the Sexual Pressure Scale for Women-Revised (SPSW-R) was tested, and principal components analysis was performed in a sample of 325 young, urban women. A parsimonious 18-item, 4-factor model explained 61% of the variance. In Study 2 the theory underlying sexual pressure was supported by confirmatory factor analysis using structural equation modeling in a sample of 181 women. Reliabilities of the SPSW-R total and subscales were very satisfactory, suggesting it may be used in intervention research. PMID:18666222

  11. Psychometric validation of the revised clinical cultural competency questionnaire.

    PubMed

    Mareno, Nicole; Hart, Patricia L; VanBrackle, Lewis

    2013-01-01

    Growing diversity in health care requires culturally competent care. Assessing nurses' cultural competence is the first step in designing cultural competency education. The Clinical Cultural Competency Questionnaire (CCCQ) is one instrument to assess nurses' cultural competence. The psychometric properties and factor structure of the revised CCCQ-PRE (CCCQ-PRE-R) for nurses was examined. A 1-factor solution was noted for the knowledge and skills subscales. A 2-factor solution was discovered for the comfort and awareness subscales: differentiating between comfort in dealing with positive and negative cross-cultural encounters/situations, and differentiating between importance awareness and self-awareness. Cronbach's alpha coefficients were high for all subscales. The findings support the use of the revised CCCQ-PRE-R with nurses. Further testing in larger, more diverse nursing populations is warranted.

  12. Fearlessness about Death: The psychometric properties and construct validity of the revision to the Acquired Capability for Suicide Scale

    PubMed Central

    Ribeiro, Jessica D.; Witte, Tracy K.; Van Orden, Kimberly A.; Selby, Edward A.; Gordon, Kathryn H.; Bender, Theodore W.; Joiner, Thomas E.

    2014-01-01

    The Interpersonal Theory of Suicide proposes that suicidal behavior is so frightening that in order for an individual to engage in suicidal behavior, desire for suicide must be accompanied by the capability to do so. The capability for suicide is characterized by both a sense of fearlessness about death and elevated physiological pain tolerance. The primary aim of the current project was to reevaluate and revise the Acquired Capability for Suicide Scale (ACSS) and offer a revision to the scale. Expert review of the scale items resulted in retaining seven items assessing fearlessness about death. The recommendation is made to refer to the revised scale as the ACSS-Fearlessness about Death (ACSS-FAD) to reflect its content more specifically. A model with the 7 retained items provided good fit to the data across three independent samples of young adults. Multiple group analyses examining measurement invariance across men and women found that the latent structure of the scale is comparable across gender. Data are also presented demonstrating convergent and discriminant validity for the scale in young adults and an inpatient psychiatric sample. Findings support the viability of the ACSS-FAD, indicating the scale has a replicable factor structure that generalizes across males and females and is substantively related to the construct of fearlessness about death. Taken together, the present work extends our knowledge of the psychometrics of the ACSS-FAD in particular and the nature of fearlessness about death in general. PMID:24274043

  13. Wet-chemical synthesis and applications of non-layer structured two-dimensional nanomaterials

    PubMed Central

    Tan, Chaoliang; Zhang, Hua

    2015-01-01

    Non-layer structured nanomaterials with single- or few-layer thickness have two-dimensional sheet-like structures and possess intriguing properties. Recent years have seen major advances in development of a host of non-layer structured ultrathin two-dimensional nanomaterials such as noble metals, metal oxides and metal chalcogenides. The wet-chemical synthesis has emerged as the most promising route towards high-yield and mass production of such nanomaterials. These nanomaterials are now finding increasing applications in a wide range of areas including catalysis, energy production and storage, sensor and nanotherapy, to name but a few. PMID:26303763

  14. Huygens' optical vector wave field synthesis via in-plane electric dipole metasurface.

    PubMed

    Park, Hyeonsoo; Yun, Hansik; Choi, Chulsoo; Hong, Jongwoo; Kim, Hwi; Lee, Byoungho

    2018-04-16

    We investigate Huygens' optical vector wave field synthesis scheme for electric dipole metasurfaces with the capability of modulating in-plane polarization and complex amplitude and discuss the practical issues involved in realizing multi-modulation metasurfaces. The proposed Huygens' vector wave field synthesis scheme identifies the vector Airy disk as a synthetic unit element and creates a designed vector optical field by integrating polarization-controlled and complex-modulated Airy disks. The metasurface structure for the proposed vector field synthesis is analyzed in terms of the signal-to-noise ratio of the synthesized field distribution. The design of practical metasurface structures with true vector modulation capability is possible through the analysis of the light field modulation characteristics of various complex modulated geometric phase metasurfaces. It is shown that the regularization of meta-atoms is a key factor that needs to be considered in field synthesis, given that it is essential for a wide range of optical field synthetic applications, including holographic displays, microscopy, and optical lithography.

  15. Mechanism for priming DNA synthesis by yeast DNA Polymerase α

    PubMed Central

    Perera, Rajika L; Torella, Rubben; Klinge, Sebastian; Kilkenny, Mairi L; Maman, Joseph D; Pellegrini, Luca

    2013-01-01

    The DNA Polymerase α (Pol α)/primase complex initiates DNA synthesis in eukaryotic replication. In the complex, Pol α and primase cooperate in the production of RNA-DNA oligonucleotides that prime synthesis of new DNA. Here we report crystal structures of the catalytic core of yeast Pol α in unliganded form, bound to an RNA primer/DNA template and extending an RNA primer with deoxynucleotides. We combine the structural analysis with biochemical and computational data to demonstrate that Pol α specifically recognizes the A-form RNA/DNA helix and that the ensuing synthesis of B-form DNA terminates primer synthesis. The spontaneous release of the completed RNA-DNA primer by the Pol α/primase complex simplifies current models of primer transfer to leading- and lagging strand polymerases. The proposed mechanism of nucleotide polymerization by Pol α might contribute to genomic stability by limiting the amount of inaccurate DNA to be corrected at the start of each Okazaki fragment. DOI: http://dx.doi.org/10.7554/eLife.00482.001 PMID:23599895

  16. The Total Synthesis Problem of linear multivariable control. II - Unity feedback and the design morphism

    NASA Technical Reports Server (NTRS)

    Sain, M. K.; Antsaklis, P. J.; Gejji, R. R.; Wyman, B. F.; Peczkowski, J. L.

    1981-01-01

    Zames (1981) has observed that there is, in general, no 'separation principle' to guarantee optimality of a division between control law design and filtering of plant uncertainty. Peczkowski and Sain (1978) have solved a model matching problem using transfer functions. Taking into consideration this investigation, Peczkowski et al. (1979) proposed the Total Synthesis Problem (TSP), wherein both the command/output-response and command/control-response are to be synthesized, subject to the plant constraint. The TSP concept can be subdivided into a Nominal Design Problem (NDP), which is not dependent upon specific controller structures, and a Feedback Synthesis Problem (FSP), which is. Gejji (1980) found that NDP was characterized in terms of the plant structural matrices and a single, 'good' transfer function matrix. Sain et al. (1981) have extended this NDP work. The present investigation is concerned with a study of FSP for the unity feedback case. NDP, together with feedback synthesis, is understood as a Total Synthesis Problem.

  17. Organic Explosives and Related Compounds. Environmental and Health Considerations

    DTIC Science & Technology

    1989-03-01

    compounds used as explosives and in propellant formulations. While a summiary of synthetic processes is included, emphasis is focused on behavior and...INTRODUCTION .......................................................... 3 SYNTHESIS/ PRODUCTION AND USE .......................................... 5...2 , NG PA DEGDN C(CH2 ON02)4 PETN Figure 1. Structures of Explosives and Related Compounds SYNTHESIS/ PRODUCTION AND USE Methods for the synthesis or

  18. On-Line Synthesis and Analysis by Mass Spectrometry

    ERIC Educational Resources Information Center

    Bain, Ryan M.; Pulliam, Christopher J.; Raab, Shannon A.; Cooks, R. Graham

    2015-01-01

    In this laboratory experiment, students learn how to use ESI to accelerate chemical synthesis and to couple it with on-line mass spectrometry for structural analysis. The Hantzsch synthesis of symmetric 1,4-dihydropyridines is a classic example of a one-pot reaction in which multiple intermediates can serve to indicate the progress of the reaction…

  19. Detention of People Lost to Follow-Up on TB Treatment in Kenya

    PubMed Central

    Restoy, Enrique; Kibuchi, Evaline; Holland, Paula; Harries, Anthony D.

    2016-01-01

    Abstract Adherence to treatment is a key element for global TB control. Public health laws can be used to enforce isolation, adherence, and completion of TB treatment. However, the practical application of public health laws can potentially range from voluntary measures to involuntary detention approaches. This paper explores the potential risks and impacts of using detention approaches to enforce TB treatment adherence. In August 2015, we conducted a literature search regarding the application of public health laws to enforce adherence to TB treatment globally, and specifically in Kenya. Texts were analyzed using narrative synthesis. Results indicated that in Kenya, people lost to follow-up on TB treatment were frequently detained in prisons. However, incarceration and detention approaches curtail the rights to health, informed consent, privacy, freedom from non-consensual treatment, freedom from inhumane and degrading treatment, and freedom of movement of people lost to follow-up. Detention could also worsen social inequalities and lead to a paradoxical increase in TB incidence. We suggest the incorporation of less intrusive solutions in legislation and policies. These include strengthening health systems to reduce dependency on prisons as isolation spaces, decentralizing TB treatment to communities, enhancing treatment education, revising the public health laws, and addressing socioeconomic and structural determinants associated with TB incidence and loss to follow-up. PMID:27780998

  20. A review on the synthesis, crystal growth, structure and physical properties of rare earth based quaternary intermetallic compounds

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mumbaraddi, Dundappa; Sarkar, Sumanta; Peter, Sebastian C., E-mail: sebastiancp@jncasr.ac.in

    2016-04-15

    This review highlights the synthesis and crystal growth of quaternary intermetallic compounds based on rare earth metals. In the first part of this review, we highlight briefly about intermetallics and their versatile properties in comparison to the constituent elements. In the next part, we have discussed about various synthesis techniques with more focus on the metal flux technique towards the well shaped crystal growth of novel compounds. In the subsequent parts, several disordered quaternary compounds have been reviewed and then outlined most known ordered quaternary compounds with their complex structure. A special attention has been given to the ordered compoundsmore » with structural description and relation to the parent binary and ternary compounds. The importance of electronic and structural feature is highlighted as the key roles in designing these materials for emerging applications. - Graphical abstract: Rare earth based quaternary intermetallic compounds crystallize in complex novel crystal structures. The diversity in the crystal structure may induce unique properties and can be considered them as future materials. - Highlights: • Crystal growth and crystal structure of quaternary rare earth based intermetallics. • Structural complexity of quaternary compounds in comparison to the parent compounds. • Novel quaternary compounds display unique crystal structure.« less

  1. Total chemical synthesis and X-ray structure of kaliotoxin by racemic protein crystallography.

    PubMed

    Pentelute, Brad L; Mandal, Kalyaneswar; Gates, Zachary P; Sawaya, Michael R; Yeates, Todd O; Kent, Stephen B H

    2010-11-21

    Here we report the total synthesis of kaliotoxin by 'one pot' native chemical ligation of three synthetic peptides. A racemic mixture of D- and L-kaliotoxin synthetic protein molecules gave crystals in the centrosymmetric space group P1 that diffracted to atomic-resolution (0.95 Å), enabling the X-ray structure of kaliotoxin to be determined by direct methods.

  2. 3-cyanoindole-based inhibitors of inosine monophosphate dehydrogenase: synthesis and initial structure-activity relationships.

    PubMed

    Dhar, T G Murali; Shen, Zhongqi; Gu, Henry H; Chen, Ping; Norris, Derek; Watterson, Scott H; Ballentine, Shelley K; Fleener, Catherine A; Rouleau, Katherine A; Barrish, Joel C; Townsend, Robert; Hollenbaugh, Diane L; Iwanowicz, Edwin J

    2003-10-20

    A series of novel small molecule inhibitors of inosine monophosphate dehydrogenase (IMPDH), based upon a 3-cyanoindole core, were explored. IMPDH catalyzes the rate determining step in guanine nucleotide biosynthesis and is a target for anticancer, immunosuppressive and antiviral therapy. The synthesis and the structure-activity relationships (SAR), derived from in vitro studies, for this new series of inhibitors is given.

  3. Screening of ligands for the Ullmann synthesis of electron-rich diaryl ethers.

    PubMed

    Otto, Nicola; Opatz, Till

    2012-01-01

    In the search for new ligands for the Ullmann diaryl ether synthesis, permitting the coupling of electron-rich aryl bromides at relatively low temperatures, 56 structurally diverse multidentate ligands were screened in a model system that uses copper iodide in acetonitrile with potassium phosphate as the base. The ligands differed largely in their performance, but no privileged structural class could be identified.

  4. Aircraft interior noise prediction using a structural-acoustic analogy in NASTRAN modal synthesis

    NASA Technical Reports Server (NTRS)

    Grosveld, Ferdinand W.; Sullivan, Brenda M.; Marulo, Francesco

    1988-01-01

    The noise induced inside a cylindrical fuselage model by shaker excitation is investigated theoretically and experimentally. The NASTRAN modal-synthesis program is used in the theoretical analysis, and the predictions are compared with experimental measurements in extensive graphs. Good general agreement is obtained, but the need for further refinements to account for acoustic-cavity damping and structural-acoustic interaction is indicated.

  5. Kinematic synthesis of bevel-gear-type robotic wrist mechanisms

    NASA Astrophysics Data System (ADS)

    Lin, Chen-Chou

    Bevel-gear-type robotic wrist mechanisms are commonly used in industry. The reasons for their popularity are that they are compact, light-weight, and relatively inexpensive. However, there are singularities in their workspace, which substantially degrade their manipulative performance. The objective of this research is to develop an atlas of three-degree-of-freedom bevel-gear-type wrist mechanisms, and through dimensional synthesis to improve their kinematic performance. The dissertation contains two major parts: the first is structural analysis and synthesis, the other is kinematic analysis and dimensional synthesis. To synthesize the kinematic structures of bevel-gear-type wrist mechanisms, the kinematic structures are separated from their functional considerations. All kinematic structures which satisfy the mobility condition are enumerated in an unbiased, systematic manner. Then the bevel-gear-type wrist mechanisms are identified by applying the functional requirements. Structural analysis shows that a three-degree-of-freedom wrist mechanism usually consists of non-fractionated, two degree-of-freedom epicyclic gear train jointed with the base link. Therefore, the structural synthesis can be simplified into a problem of examining the atlas of non-fractionated, two-degree-of-freedom epicyclic gear trains. The resulting bevel-gear-type wrist mechanism has been categorized and evaluated. It is shown that three-degree-of-freedom, four-jointed wrist mechanisms are promising for further improving the kinematic performance. It is found that a spherical planetary gear train is necessarily imbedded in a three-degree-of-freedom, four-jointed wrist mechanism. Therefore, to study the workspace and singularity problems of three-degree-of-freedom four-jointed spherical wrist mechanisms, we have to study the trajectories of spherical planetary gear trains. The parametric equations of the trajectories and some useful geometric properties for the analysis and synthesis of workplace are derived. The workspace boundary equations can be derived via both geometric consideration and Jacobian analysis. The workspace is divided by inner and outer boundaries into regions of accessibility of zero, two, and four. The design criteria of full workspace and a maximum four-root region are established.

  6. Factor structure of the Bulimia Test--Revised in college women from four ethnic groups.

    PubMed

    Fernandez, Senaida; Malcarne, Vanessa L; Malacrne, Vanessa L; Wilfley, Denise E; McQuaid, John

    2006-07-01

    The factor structure of the Bulimia Test--Revised (BULIT-R) was investigated using confirmatory factor analysis (CFA) and exploratory factor analysis (EFA). The sample consisted of 2,671 female college students (African American, Asian American, Caucasian American, and Latino American). Reliability coefficients were excellent across groups. African Americans scored significantly lower on the BULIT-R than Caucasian Americans. Across groups, CFA and EFA results suggest a six-factor solution is most appropriate. Consistent across groups were factors representing bingeing, body image, purging, and extreme weight loss behaviors, while few differences were observed across groups. These findings suggest that the measure is reliable and valid for use with diverse ethnic groups. Future research should focus on culturally salient psychological correlates of disordered eating in diverse ethnic groups.

  7. Rapid synthesis of triazine inhibitors of inosine monophosphate dehydrogenase.

    PubMed

    Pitts, William J; Guo, Junqing; Dhar, T G Murali; Shen, Zhongqi; Gu, Henry H; Watterson, Scott H; Bednarz, Mark S; Chen, Bang Chi; Barrish, Joel C; Bassolino, Donna; Cheney, Daniel; Fleener, Catherine A; Rouleau, Katherine A; Hollenbaugh, Diane L; Iwanowicz, Edwin J

    2002-08-19

    A series of novel triazine-based small molecule inhibitors (IV) of inosine monophosphate dehydrogenase was prepared. The synthesis and the structure-activity relationships (SAR) derived from in vitro studies are described.

  8. Synthesis of monolithic graphene – graphite integrated electronics

    PubMed Central

    Park, Jang-Ung; Nam, SungWoo; Lee, Mi-Sun; Lieber, Charles M.

    2013-01-01

    Encoding electronic functionality into nanoscale elements during chemical synthesis has been extensively explored over the past decade as the key to developing integrated nanosystems1 with functions defined by synthesis2-6. Graphene7-12 has been recently explored as a two-dimensional nanoscale material, and has demonstrated simple device functions based on conventional top-down fabrication13-20. However, the synthetic approach to encoding electronic functionality and thus enabling an entire integrated graphene electronics in a chemical synthesis had not previously been demonstrated. Here we report an unconventional approach for the synthesis of monolithically-integrated electronic devices based on graphene and graphite. Spatial patterning of heterogeneous catalyst metals permits the selective growth of graphene and graphite, with controlled number of graphene layers. Graphene transistor arrays with graphitic electrodes and interconnects were formed from synthesis. These functional, all-carbon structures were transferrable onto a variety of substrates. The integrated transistor arrays were used to demonstrate real-time, multiplexed chemical sensing, and more significantly, multiple carbon layers of the graphene-graphite device components were vertically assembled to form a three-dimensional flexible structure which served as a top-gate transistor array. These results represent a substantial progress towards encoding electronic functionality via chemical synthesis and suggest future promise for one-step integration of graphene-graphite based electronics. PMID:22101813

  9. Synthesis of monolithic graphene-graphite integrated electronics.

    PubMed

    Park, Jang-Ung; Nam, SungWoo; Lee, Mi-Sun; Lieber, Charles M

    2011-11-20

    Encoding electronic functionality into nanoscale elements during chemical synthesis has been extensively explored over the past decade as the key to developing integrated nanosystems with functions defined by synthesis. Graphene has been recently explored as a two-dimensional nanoscale material, and has demonstrated simple device functions based on conventional top-down fabrication. However, the synthetic approach to encoding electronic functionality and thus enabling an entire integrated graphene electronics in a chemical synthesis had not previously been demonstrated. Here we report an unconventional approach for the synthesis of monolithically integrated electronic devices based on graphene and graphite. Spatial patterning of heterogeneous metal catalysts permits the selective growth of graphene and graphite, with a controlled number of graphene layers. Graphene transistor arrays with graphitic electrodes and interconnects were formed from the synthesis. These functional, all-carbon structures were transferable onto a variety of substrates. The integrated transistor arrays were used to demonstrate real-time, multiplexed chemical sensing and more significantly, multiple carbon layers of the graphene-graphite device components were vertically assembled to form a three-dimensional flexible structure which served as a top-gate transistor array. These results represent substantial progress towards encoding electronic functionality through chemical synthesis and suggest the future promise of one-step integration of graphene-graphite based electronics.

  10. Synthesis and structures of metal chalcogenide precursors

    NASA Technical Reports Server (NTRS)

    Hepp, Aloysius F.; Duraj, Stan A.; Eckles, William E.; Andras, Maria T.

    1990-01-01

    The reactivity of early transition metal sandwich complexes with sulfur-rich molecules such as dithiocarboxylic acids was studied. Researchers recently initiated work on precursors to CuInSe2 and related chalcopyrite semiconductors. Th every high radiation tolerance and the high absorption coefficient of CuInSe2 makes this material extremely attractive for lightweight space solar cells. Their general approach in early transition metal chemistry, the reaction of low-valent metal complexes or metal powders with sulfur and selenium rich compounds, was extended to the synthesis of chalcopyrite precursors. Here, the researchers describe synthesis, structures, and and routes to single molecule precursors to metal chalcogenides.

  11. TiO2 synthesized by microwave assisted solvothermal method: Experimental and theoretical evaluation

    NASA Astrophysics Data System (ADS)

    Moura, K. F.; Maul, J.; Albuquerque, A. R.; Casali, G. P.; Longo, E.; Keyson, D.; Souza, A. G.; Sambrano, J. R.; Santos, I. M. G.

    2014-02-01

    In this study, a microwave assisted solvothermal method was used to synthesize TiO2 with anatase structure. The synthesis was done using Ti (IV) isopropoxide and ethanol without templates or alkalinizing agents. Changes in structural features were observed with increasing time of synthesis and evaluated using periodic quantum chemical calculations. The anatase phase was obtained after only 1 min of reaction besides a small amount of brookite phase. Experimental Raman spectra are in accordance with the theoretical one. Micrometric spheres constituted by nanometric particles were obtained for synthesis from 1 to 30 min, while spheres and sticks were observed after 60 min.

  12. Glycol-modified silanes: novel possibilities for the synthesis of hierarchically organized (hybrid) porous materials.

    PubMed

    Hartmann, Sarah; Brandhuber, Doris; Hüsing, Nicola

    2007-09-01

    The preparation of porous hierarchical architectures that have structural features spanning from the nanometer to micrometer and even larger dimensions and that exhibit certain functionalities is one of the new challenging frontiers in materials chemistry. The sol-gel process is one of the most promising synthesis routes toward such materials because it not only offers the possibility to incorporate organic functions into the porous host but also offers the possibility to deliberately tailor the pore structure. In this Account, the opportunities given by the application of novel diol-modified silanes are discussed for the synthesis of hierarchically organized inorganic and also inorganic-organic porous monoliths.

  13. The synthesis of cadmium sulfide nanoplatelets using a novel continuous flow sonochemical reactor

    DOE PAGES

    Palanisamy, Barath; Paul, Brian; Chang, Chih -hung

    2015-01-21

    A continuous flow sonochemical reactor was developed capable of producing metastable cadmium sulfide (CdS) nanoplatelets with thicknesses at or below 10 nm. The continuous flow sonochemical reactor included the passive in-line micromixing of reagents prior to sonochemical reaction. Synthesis results were compared with those from reactors involving batch conventional heating and batch ultrasound-induced heating. The continuous sonochemical synthesis was found to result in high aspect ratio hexagonal platelets of CdS possessing cubic crystal structures with thicknesses well below 10 nm. The unique shape and crystal structure of the nanoplatelets are suggestive of high localized temperatures within the sonochemical process. Asmore » a result, the particle size uniformity and product throughput are much higher for the continuous sonochemical process in comparison to the batch sonochemical process and conventional synthesis processes.« less

  14. Robotic large-scale application of wheat cell-free translation to structural studies including membrane proteins

    PubMed Central

    Beebe, Emily T.; Makino, Shin-ichi; Nozawa, Akira; Matsubara, Yuko; Frederick, Ronnie O.; Primm, John G.; Goren, Michael A.; Fox, Brian G.

    2010-01-01

    The use of the Protemist XE, an automated discontinuous-batch protein synthesis robot, in cell-free translation is reported. The soluble Galdieria sulphuraria protein DCN1 was obtained in greater than 2 mg total synthesis yield per mL of reaction mixture from the Protemist XE, and the structure was subsequently solved by X-ray crystallography using material from one 10 mL synthesis (PDB ID: 3KEV). The Protemist XE was also capable of membrane protein translation. Thus human sigma-1 receptor was translated in the presence of unilamellar liposomes and bacteriorhodopsin was translated directly into detergent micelles in the presence of all-trans-retinal. The versatility, ease of use, and compact size of the Protemist XE robot demonstrate its suitability for large-scale synthesis of many classes of proteins. PMID:20637905

  15. Synthesis and characterization of nanosized MgxMn1-xFe2O4 ferrites by both sol-gel and thermal decomposition methods

    NASA Astrophysics Data System (ADS)

    De-León-Prado, Laura Elena; Cortés-Hernández, Dora Alicia; Almanza-Robles, José Manuel; Escobedo-Bocardo, José Concepción; Sánchez, Javier; Reyes-Rdz, Pamela Yajaira; Jasso-Terán, Rosario Argentina; Hurtado-López, Gilberto Francisco

    2017-04-01

    This work reports the synthesis of MgxMn1-xFe2O4 (x=0-1) nanoparticles by both sol-gel and thermal decomposition methods. In order to determine the effect of synthesis conditions on the crystal structure and magnetic properties of the ferrites, the synthesis was carried out varying some parameters, including composition. By both methods it was possible to obtain ferrites having a single crystalline phase with cubic inverse spinel structure and a behavior near to that of superparamagnetic materials. Saturation magnetization values were higher for materials synthesized by sol-gel. Furthermore, in both cases particles have a spherical-like morphology and nanometric sizes (11-15 nm). Therefore, these materials can be used as thermoseeds for the treatment of cancer by magnetic hyperthermia.

  16. Why an extended evolutionary synthesis is necessary

    PubMed Central

    2017-01-01

    Since the last major theoretical integration in evolutionary biology—the modern synthesis (MS) of the 1940s—the biosciences have made significant advances. The rise of molecular biology and evolutionary developmental biology, the recognition of ecological development, niche construction and multiple inheritance systems, the ‘-omics’ revolution and the science of systems biology, among other developments, have provided a wealth of new knowledge about the factors responsible for evolutionary change. Some of these results are in agreement with the standard theory and others reveal different properties of the evolutionary process. A renewed and extended theoretical synthesis, advocated by several authors in this issue, aims to unite pertinent concepts that emerge from the novel fields with elements of the standard theory. The resulting theoretical framework differs from the latter in its core logic and predictive capacities. Whereas the MS theory and its various amendments concentrate on genetic and adaptive variation in populations, the extended framework emphasizes the role of constructive processes, ecological interactions and systems dynamics in the evolution of organismal complexity as well as its social and cultural conditions. Single-level and unilinear causation is replaced by multilevel and reciprocal causation. Among other consequences, the extended framework overcomes many of the limitations of traditional gene-centric explanation and entails a revised understanding of the role of natural selection in the evolutionary process. All these features stimulate research into new areas of evolutionary biology. PMID:28839929

  17. Can we Build on Social Movement Theories to Develop and Improve Community-Based Participatory Research? A Framework Synthesis Review.

    PubMed

    Tremblay, Marie-Claude; Martin, Debbie H; Macaulay, Ann C; Pluye, Pierre

    2017-06-01

    A long-standing challenge in community-based participatory research (CBPR) has been to anchor practice and evaluation in a relevant and comprehensive theoretical framework of community change. This study describes the development of a multidimensional conceptual framework that builds on social movement theories to identify key components of CBPR processes. Framework synthesis was used as a general literature search and analysis strategy. An initial conceptual framework was developed from the theoretical literature on social movement. A literature search performed to identify illustrative CBPR projects yielded 635 potentially relevant documents, from which eight projects (corresponding to 58 publications) were retained after record and full-text screening. Framework synthesis was used to code and organize data from these projects, ultimately providing a refined framework. The final conceptual framework maps key concepts of CBPR mobilization processes, such as the pivotal role of the partnership; resources and opportunities as necessary components feeding the partnership's development; the importance of framing processes; and a tight alignment between the cause (partnership's goal), the collective action strategy, and the system changes targeted. The revised framework provides a context-specific model to generate a new, innovative understanding of CBPR mobilization processes, drawing on existing theoretical foundations. © 2017 The Authors American Journal of Community Psychology published by Wiley Periodicals, Inc. on behalf of Society for Community Research and Action.

  18. Optimal aperture synthesis radar imaging

    NASA Astrophysics Data System (ADS)

    Hysell, D. L.; Chau, J. L.

    2006-03-01

    Aperture synthesis radar imaging has been used to investigate coherent backscatter from ionospheric plasma irregularities at Jicamarca and elsewhere for several years. Phenomena of interest include equatorial spread F, 150-km echoes, the equatorial electrojet, range-spread meteor trails, and mesospheric echoes. The sought-after images are related to spaced-receiver data mathematically through an integral transform, but direct inversion is generally impractical or suboptimal. We instead turn to statistical inverse theory, endeavoring to utilize fully all available information in the data inversion. The imaging algorithm used at Jicamarca is based on an implementation of the MaxEnt method developed for radio astronomy. Its strategy is to limit the space of candidate images to those that are positive definite, consistent with data to the degree required by experimental confidence limits; smooth (in some sense); and most representative of the class of possible solutions. The algorithm was improved recently by (1) incorporating the antenna radiation pattern in the prior probability and (2) estimating and including the full error covariance matrix in the constraints. The revised algorithm is evaluated using new 28-baseline electrojet data from Jicamarca.

  19. Localized synthesis, assembly and integration of silicon nanowires

    NASA Astrophysics Data System (ADS)

    Englander, Ongi

    Localized synthesis, assembly and integration of one-dimensional silicon nanowires with MEMS structures is demonstrated and characterized in terms of local synthesis processes, electric-field assisted self-assembly, and a proof-of-concept nanoelectromechanical system (HEMS) demonstration. Emphasis is placed on the ease of integration, process control strategies, characterization techniques and the pursuit of integrated devices. A top-down followed by a bottom-up integration approach is utilized. Simple MEMS heater structures are utilized as the microscale platforms for the localized, bottom-up synthesis of one-dimensional nanostructures. Localized heating confines the high temperature region permitting only localized nanostructure synthesis and allowing the surroundings to remain at room temperature thus enabling CMOS compatible post-processing. The vapor-liquid-solid (VLS) process in the presence of a catalytic nanoparticle, a vapor phase reactant, and a specific temperature environment is successfully employed locally. Experimentally, a 5nm thick gold-palladium layer is used as the catalyst while silane is the vapor phase reactant. The current-voltage behavior of the MEMS structures can be correlated to the approximate temperature range required for the VLS reaction to take place. Silicon nanowires averaging 45nm in diameter and up to 29mum in length synthesized at growth rates of up to 1.5mum/min result. By placing two MEMS structures in close proximity, 4--10mum apart, localized silicon nanowire growth can be used to link together MEMS structures to yield a two-terminal, self-assembled micro-to-nano system. Here, one MEMS structure is designated as the hot growth structure while a nearby structure is designated as the cold secondary structure, whose role is to provide a natural stopping point for the VLS reaction. The application of a localized electric-field, 5 to 13V/mum in strength, during the synthesis process, has been shown to improve nanowire organization, alignment, and assembly. The integrated nanoelectrormechanical system was found to be mechanically resilient as it proved to successfully withstand a wide variety of post-processing steps, including manipulations and examinations under scanning and transmission electron microscopes and aqueous processing, although a super critical drying step is necessary to preserve the integrated system during the drying process. Electrical characterization of the system proved challenging due to low carrier concentration and possible transport issues at the nano-micro interface. Nonetheless, in a proof-of-concept demonstration, the system was functionalized and tested for a hydrogen sensing application.

  20. Adaptation of the three-dimensional wisdom scale (3D-WS) for the Korean cultural context.

    PubMed

    Kim, Seungyoun; Knight, Bob G

    2014-10-23

    ABSTRACT Background: Previous research on wisdom has suggested that wisdom is comprised of cognitive, reflective, and affective components and has developed and validated wisdom measures based on samples from Western countries. To apply the measurement to Eastern cultures, the present study revised an existing wisdom scale, the three-dimensional wisdom scale (3D-WS, Ardelt, 2003) for the Korean cultural context. Methods: Participants included 189 Korean heritage adults (age range 19-96) living in Los Angeles. We added a culturally specific factor of wisdom to the 3D-WS: Modesty and Unobtrusiveness (Yang, 2001), which captures an Eastern aspect of wisdom. The structure and psychometrics of the scale were tested. By latent cluster analysis, we determined acculturation subgroups and examined group differences in the means of factors in the revised wisdom scale (3D-WS-K). Results: Three factors, Cognitive Flexibility, Viewpoint Relativism, and Empathic Modesty were found using confirmatory factor analysis. Respondents with high biculturalism were higher on Viewpoint Relativism and lower on Empathic Modesty. Conclusion: This study discovered that a revised wisdom scale had a distinct factor structure and item content in a Korean heritage sample. We also found acculturation influences on the meaning of wisdom.

  1. The Rehabilitation Medicine Scientist Training Program

    PubMed Central

    Whyte, John; Boninger, Michael; Helkowski, Wendy; Braddom-Ritzler, Carolyn

    2016-01-01

    Physician scientists are seen as important in healthcare research. However, the number of physician scientists and their success in obtaining NIH funding have been declining for many years. The shortage of physician scientists in Physical Medicine and Rehabilitation is particularly severe, and can be attributed to many of the same factors that affect physician scientists in general, as well as to the lack of well developed models for research training. In 1995, the Rehabilitation Medicine Scientist Training Program (RMSTP) was funded by a K12 grant from the National Center of Medical Rehabilitation Research (NCMRR), as one strategy for increasing the number of research-productive physiatrists. The RMSTP's structure was revised in 2001 to improve the level of preparation of incoming trainees, and to provide a stronger central mentorship support network. Here we describe the original and revised structure of the RMSTP and review subjective and objective data on the productivity of the trainees who have completed the program. These data suggest that RMSTP trainees are, in general, successful in obtaining and maintaining academic faculty positions and that the productivity of the cohort trained after the revision, in particular, shows impressive growth after about 3 years of training. PMID:19847126

  2. Negotiating Intersex: A Case for Revising the Theory of Social Diagnosis

    PubMed Central

    Short, Susan E.

    2017-01-01

    The theory of social diagnosis recognizes two principles: 1) extra-medical social structures frame diagnosis; and 2) myriad social actors, in addition to clinicians, contribute to diagnostic labels and processes. The relationship between social diagnosis and (de)medicalization remains undertheorized, however, because social diagnosis does not account for how social actors can also resist the pathologization of symptoms and conditions—sometimes at the same time as they clamor for medical recognition—thereby shaping societal definitions of disease in different, but no less important, ways. In this article, we expand the social diagnosis framework by adding a third principle, specifically that 3) social actors engage with social structures to both contribute to, and resist, the framing of a condition as pathological (i.e. medicalization and demedicalization). This revised social diagnosis framework allows for the systematic investigation of multi-directional, dynamic processes, formalizing the link between diagnosis and (de)medicalization. It also responds to long-standing calls for more contextualized research in (de)medicalization studies by offering a framework that explicitly accounts for the social contexts in which (de)medicalizing processes operate. To showcase the utility of this revised framework, we use it to guide our analyses of a highly negotiated diagnosis: intersex. PMID:28073070

  3. Solution Synthesis of Atomically Precise Graphene Nanoribbons

    NASA Astrophysics Data System (ADS)

    Shekhirev, Mikhail; Sinitskii, Alexander

    2017-05-01

    Bottom-up fabrication of narrow strips of graphene, also known as graphene nanoribbons or GNRs, is an attractive way to open a bandgap in semimetallic graphene. In this chapter, we review recent progress in solution-based synthesis of GNRs with atomically precise structures. We discuss a variety of atomically precise GNRs and highlight theoretical and practical aspects of their structural design and solution synthesis. These GNRs are typically synthesized through a polymerization of rationally designed molecular precursors followed by a planarization through a cyclodehydrogenation reaction. We discuss various synthetic techniques for polymerization and planarization steps, possible approaches for chemical modification of GNRs, and compare the properties of GNRs that could be achieved by different synthetic methods. We also discuss the importance of the rational design of molecular precursors to avoid isomerization during the synthesis and achieve GNRs that have only one possible structure. Significant attention in this chapter is paid to the methods of material characterization of solution-synthesized GNRs. The chapter is concluded with the discussion of the most significant challenges in the field and the future outlook.

  4. Synthesis and characterization of hexaarylbenzenes with five or six different substituents enabled by programmed synthesis

    NASA Astrophysics Data System (ADS)

    Suzuki, Shin; Segawa, Yasutomo; Itami, Kenichiro; Yamaguchi, Junichiro

    2015-03-01

    Since its discovery in 1825, benzene has served as one of the most used and indispensable building blocks of chemical compounds, ranging from pharmaceuticals and agrochemicals to plastics and those used in organic electronic devices. Benzene has six hydrogen atoms that can each be replaced by different substituents, which means that the structural diversity of benzene derivatives is intrinsically extraordinary. The number of possible substituted benzenes from n different substituents is (2n + 2n2 + 4n3 + 3n4 + n6)/12. However, owing to a lack of general synthetic methods for making multisubstituted benzenes, this potentially huge structural diversity has not been fully exploited. Here, we describe a programmed synthesis of hexaarylbenzenes using C-H activation, cross-coupling and [4+2] cycloaddition reactions. The present method allows for the isolation and structure-property characterization of hexaarylbenzenes with distinctive aryl substituents at all positions for the first time. Moreover, the established protocol can be applied to the synthesis of tetraarylnaphthalenes and pentaarylpyridines.

  5. Force fields for describing the solution-phase synthesis of shape-selective metal nanoparticles

    NASA Astrophysics Data System (ADS)

    Zhou, Ya; Al-Saidi, Wissam; Fichthorn, Kristen

    2013-03-01

    Polyvinylpyrrolidone (PVP) and polyethylene oxide (PEO) are structure-directing agents that exhibit different performance in the polyol synthesis of Ag nanostructures. The success of these structure-directing agents in selective nanostructure synthesis is often attributed to their selective binding to Ag(100) facets. We use first-principles, density-functional theory (DFT) calculations in a vacuum environment to show that PVP has a stronger preference to bind to Ag(100) than to Ag(111), whereas PEO exhibits much weaker selectivity. To understand the role of solvent in the surface-sensitive binding, we develop classical force fields to describe the interactions of the structure-directing (PVP and PEO) and solvent (ethylene glycol) molecules with various Ag substrates. We parameterize the force fields through force-and-energy matching to DFT results using simulated annealing. We validate the force fields by comparisons to DFT and experimental binding energies. Our force fields reproduce the surface-sensitive binding predicted by DFT calculations. Molecular dynamics simulations based on these force fields can be used to reveal the role of solvent, polymer chain length, and polymer concentration in the selective synthesis of Ag nanostructures.

  6. 30 CFR 914.25 - Approval of Indiana abandoned mine land reclamation plan amendments.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., land acquisition, rights of entry, lien consideration, public participation, procurement, accounting systems, endangered and threatened species listing, revised administrative and management structure of the...

  7. Advances on Semisynthesis, Total Synthesis, and Structure-Activity Relationships of Honokiol and Magnolol Derivatives.

    PubMed

    Yang, Chun; Zhi, Xiaoyan; Xu, Hui

    2016-01-01

    Honokiol and magnolol (an isomer of honokiol) are small-molecule polyphenols isolated from the barks of Magnolia officinalis, which have been widely used in traditional Chinese and Japanese medicines. In the last decade, a variety of biological properties of honokiol and magnolol (e.g., anti-oxidativity, antitumor activity, anti-depressant activity, anti-inflammatory activity, neuroprotective activity, anti-diabetic activity, antiviral activity, and antimicrobial activity) have been reported. Meanwhile, certain mechanisms of action of some biological activities were also investigated. Moreover, many analogs of honokiol and magnolol were prepared by structural modification or total synthesis, and some exhibited very potent pharmacological activities with improved water solubility. Therefore, the present review will provide a systematic coverage on recent developments of honokiol and magnolol derivatives in regard to semisynthesis, total synthesis, and structure-activity relationships from 2000 up to now.

  8. Comment on the paper "Synthesis, growth, structural, spectral, thermal, chemical etching, linear and nonlinear optical and mechanical studies of an organic single crystal 4-chloro 4-nitrostilbene (CONS): a potential NLO material" by P.M. Dinakaran, S. Kalainathan [Spectrochim. Acta A 111 (2013) 123-130].

    PubMed

    Srinivasan, Bikshandarkoil R; Dhuri, Sunder N; Nadkarni, V S

    2014-01-03

    We argue that (trans)-4-chloro-4'-nitrostilbene is not a new organic nonlinear optical material as claimed by Dinakaran and Kalainathan [P.M. Dinakaran, S. Kalainathan, Synthesis, growth, structural, spectral, thermal, chemical etching, linear and nonlinear optical and mechanical studies of an organic single crystal 4-Chloro 4-Nitrostilbene (CONS): a potential NLO material, Spectrochim. Acta A 111 (2013) 123-130], but instead a well-known compound whose synthesis, spectral data, single crystal structure and second harmonic generation (SHG) efficiency are well documented in the literature. The title paper is completely erroneous. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Synthesis and biological assessment of 3,7-dihydroxytropolones.

    PubMed

    Hirsch, D R; Schiavone, D V; Berkowitz, A J; Morrison, L A; Masaoka, T; Wilson, J A; Lomonosova, E; Zhao, H; Patel, B S; Datla, S H; Hoft, S G; Majidi, S J; Pal, R K; Gallicchio, E; Tang, L; Tavis, J E; Le Grice, S F J; Beutler, J A; Murelli, R P

    2017-12-19

    3,7-Dihydroxytropolones (3,7-dHTs) are highly oxygenated troponoids that have been identified as lead compounds for several human diseases. To date, structure-function studies on these molecules have been limited due to a scarcity of synthetic methods for their preparation. New synthetic strategies towards structurally novel 3,7-dHTs would be valuable in further studying their therapeutic potential. Here we describe the successful adaptation of a [5 + 2] oxidopyrilium cycloaddition/ring-opening for 3,7-dHT synthesis, which we apply in the synthesis of a plausible biosynthetic intermediate to the natural products puberulic and puberulonic acid. We have also tested these new compounds in several biological assays related to human immunodeficiency virus (HIV), hepatitis B virus (HBV) and herpes simplex virus (HSV) in order to gain insight into structure-functional analysis related to antiviral troponoid development.

  10. "Pruning of biomolecules and natural products (PBNP)": an innovative paradigm in drug discovery.

    PubMed

    Bathula, Surendar Reddy; Akondi, Srirama Murthy; Mainkar, Prathama S; Chandrasekhar, Srivari

    2015-06-21

    The source or inspiration of many marketed drugs can be traced back to natural product research. However, the chemical structure of natural products covers a wide spectrum from very simple to complex. With more complex structures it is often desirable to simplify the molecule whilst retaining the desired biological activity. This approach seeks to identify the structural unit or pharmacophore responsible for the desired activity. Such pharmacophores have been the start point for a wide range of lead generation and optimisation programmes using techniques such as Biology Oriented Synthesis, Diversity Oriented Synthesis, Diverted Total Synthesis, and Fragment Based Drug Discovery. This review discusses the literature precedence of simplification strategies in four areas of natural product research: proteins, polysaccharides, nucleic acids, and compounds isolated from natural product extracts, and their impact on identifying therapeutic products.

  11. Iron Containing Metal-Organic Frameworks: Structure, Synthesis, and Applications in Environmental Remediation.

    PubMed

    Liu, Xiaocheng; Zhou, Yaoyu; Zhang, Jiachao; Tang, Lin; Luo, Lin; Zeng, Guangming

    2017-06-21

    Metal-organic frameworks (MOFs) with Fe content are gradually developing into an independent branch in environmental remediation, requiring economical, effective, low-toxicity strategies to the complete procedure. In this review, recent advancements in the structure, synthesis, and environmental application focusing on the mechanism are presented. The unique structure of novel design proposed specific characteristics of different iron-containing MOFs with potential innovation. Synthesis of typical MILs, NH 2 -MILs and MILs based materials reveal the basis and defect of the current method, indicating the optimal means for the actual requirements. The adsorption of various contamination with multiple interaction as well as the catalytic degradation over radicals or electron-hole pairs are reviewed. This review implied considerable prospects of iron-containing MOFs in the field of environment and a more comprehensive cognition into the challenges and potential improvement.

  12. Synthesis, structure, antimycobacterial and anticancer evaluation of new pyrrolo-phenanthroline derivatives.

    PubMed

    Al Matarneh, Cristina M; Mangalagiu, Ionel I; Shova, Sergiu; Danac, Ramona

    2016-01-01

    A study concerning design, synthesis, structure and in vitro antimycobacterial and anticancer evaluation of new fused derivatives with pyrrolo[2,1-c][4,7]phenanthroline skeleton is described. The strategy adopted for synthesis involves a [3 + 2] dipolar cycloaddition of several in situ generated 4,7-phenanthrolin-4-ium ylides to different substituted alkynes and alkenes. Stereo- and regiochemistry of cycloaddition reactions were discussed. The structure of the new compounds was proven unambiguously, single-crystal X-ray diffraction studies including. The antimycobacterial and anticancer activity of a selection of new synthesized compounds was evaluated against Mycobacterium tuberculosis H37Rv under aerobic conditions and 60 human tumour cell line panel, respectively. Five of the tested compounds possess a moderate antimycobacterial activity, while two of the compounds have a significant antitumor activity against renal cancer and breast cancer.

  13. Integrated Science Assessment (ISA) for Oxides of Nitrogen ...

    EPA Pesticide Factsheets

    This draft ISA document represents a concise synthesis and evaluation of the most policy-relevant science and will ultimately provide the scientific bases for EPA’s decision on retaining or revising the current secondary standards for NO2, SO2, PM 2.5 and PM 10 since the prior release of the assessment. The intent of the ISA, according to the CAA, is to “accurately reflect the latest scientific knowledge expected from the presence of [a] pollutant in ambient air” (U.S. Code, 1970a, 1970b). It includes scientific research from atmospheric sciences, exposure and deposition, biogeochemistry, hydrology, soil science, marine science, plant physiology, animal physiology, and ecology conducted at multiple scales (e.g., population, community, ecosystem, landscape levels). Key information and judgments formerly found in the Air Quality Criteria Documents (AQCDs) for oxides of nitrogen, oxides of nitrogen and particulate matter for ecological effects are included; Appendixes provide additional details supporting the ISA. Together, the ISA and Appendixes serve to update and revise the last oxides of nitrogen and oxides of sulfur ISA which was published in 2008 and the ecological portion of the last particulate matter ISA, which was published in 2009.

  14. Year 3 ASK/FOSS Efficacy Study. CRESST Report 782

    ERIC Educational Resources Information Center

    Osmundson, Ellen; Dai, Yunyun; Herman, Joan

    2011-01-01

    This efficacy study was designed to examine the traditional FOSS curriculum (Delta Publishing, Full Option Science System/FOSS, magnetism and electricity, structures of life, and water modules, 2005), and the new ASK/FOSS curriculum (magnetism and electricity, structures of life, and water modules, 2005), a revised version of the original FOSS…

  15. Units Coordination and the Construction of Improper Fractions: A Revision of the Splitting Hypothesis

    ERIC Educational Resources Information Center

    Hackenberg, Amy J.

    2007-01-01

    This article communicates findings from a year-long constructivist teaching experiment about the relationship between four sixth-grade students' multiplicative structures and their construction of improper fractions. Students' multiplicative structures are the units coordinations that they can take as given prior to activity--i.e., the units…

  16. The Effect of Topical Structure Analysis Instruction on University Students' Writing Quality

    ERIC Educational Resources Information Center

    Liangprayoon, Somlak; Chaya, Walaiporn; Thep-ackraphong, Tipa

    2013-01-01

    Coherence is considered one of the characteristics of effective writing. Topical structure analysis (TSA) has been taught to students as a revision strategy to raise their awareness of importance of textual coherence and helps them clearly understand its concept. This study aimed to investigate the effectiveness of TSA instruction in improving…

  17. 75 FR 3223 - California Independent System Operator Corporation; Midwest Independent Transmission System...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-20

    ... the RTO/ISO stakeholder process and governance structure. First, NASUCA states that it is necessary to...' Council filed a motion to lodge a report on RTO/ISO governance written by the National Association of... wherever possible. Next, NASUCA proposes a revised governance structure that reflects consumer interests at...

  18. WISC-R Factor Structures for Diagnosed Learning Disabled Navajo and Papago Children.

    ERIC Educational Resources Information Center

    Zarske, John A.; And Others

    1981-01-01

    Wechsler Intelligence Scale for Children (Revised) (WISC-R) factor structures were compared for learning disabled Navajo and Papago children. Results support the validity of the WISC-R as a measure of general intellectual functioning, and verbal and performance aspects for both groups, indicating its appropriateness for diverse groups of children.…

  19. Symbols, Relations, and Structural Complexity.

    ERIC Educational Resources Information Center

    Reich, Peter A.

    This paper discusses an alternate formalism for context-free phrase structure grammar. The author feels that if a grammar is stated completely explicitly it can be represented in the form of a relational network of the type proposed by Lamb. He discusses some formal properties of such networks and makes some revisions to Lamb's formulation which…

  20. Writing To Learn in Science: A Curriculum Guide.

    ERIC Educational Resources Information Center

    Chatel, Regina G.

    This curriculum guide supports and gives structure to engaging students in writing-to-learn activities in science classes by delineating writing outcomes and assessment. The guide is structured according to the beliefs that students need models, revision is the key to successful writing, writing is a tool for demonstrating learning, and writing is…

  1. Diversity-Oriented Synthesis as a Strategy for Fragment Evolution against GSK3β

    PubMed Central

    2016-01-01

    Traditional fragment-based drug discovery (FBDD) relies heavily on structural analysis of the hits bound to their targets. Herein, we present a complementary approach based on diversity-oriented synthesis (DOS). A DOS-based fragment collection was able to produce initial hit compounds against the target GSK3β, allow the systematic synthesis of related fragment analogues to explore fragment-level structure–activity relationship, and finally lead to the synthesis of a more potent compound. PMID:27660690

  2. Chemical Synthesis of Proteins

    PubMed Central

    Nilsson, Bradley L.; Soellner, Matthew B.; Raines, Ronald T.

    2010-01-01

    Proteins have become accessible targets for chemical synthesis. The basic strategy is to use native chemical ligation, Staudinger ligation, or other orthogonal chemical reactions to couple synthetic peptides. The ligation reactions are compatible with a variety of solvents and proceed in solution or on a solid support. Chemical synthesis enables a level of control on protein composition that greatly exceeds that attainable with ribosome-mediated biosynthesis. Accordingly, the chemical synthesis of proteins is providing previously unattainable insight into the structure and function of proteins. PMID:15869385

  3. An efficient synthesis strategy for metal-organic frameworks: Dry-gel synthesis of MOF-74 framework with high yield and improved performance

    DOE PAGES

    Das, Atanu Kumar; Vemuri, Rama Sesha; Kutnyakov, Igor; ...

    2016-06-16

    Here, vapor-assisted dry-gel synthesis of MOF-74 structure, specifically NiMOF-74 from its synthetic precursors, was conducted with high yield and improved performance showing promise for gas (CO 2) and water adsorption applications. Unlike conventional synthesis, which takes 72 h, this kinetic study showed that NiMOF-74 forms within 12 h under dry-gel conditions with similar performance characteristics and exhibits the best performance characteristics after 48 h of heating.

  4. Arzanol, an anti-inflammatory and anti-HIV-1 phloroglucinol alpha-Pyrone from Helichrysum italicum ssp. microphyllum.

    PubMed

    Appendino, Giovanni; Ottino, Michela; Marquez, Nieves; Bianchi, Federica; Giana, Anna; Ballero, Mauro; Sterner, Olov; Fiebich, Bernd L; Munoz, Eduardo

    2007-04-01

    An acetone extract of Helichrysum italicum ssp. microphyllum afforded the phloroglucinol alpha-pyrone arzanol (1a) as a potent NF-kappaB inhibitor. Arzanol is identical with homoarenol (2a), whose structure should be revised. The phloroglucinol-type structure of arzanol and the 1,2,4-trihydroxyphenyl-type structure of the base-induced fragmentation product of homoarenol could be reconciled in light of a retro-Fries-type fragmentation that triggers a change of the hydroxylation pattern of the aromatic moiety. On the basis of these findings, the structure of arenol, the major constituent of the clinically useful antibiotic arenarin, should be revised from 2b to 1b, solving a long-standing puzzle over its biogenetic derivation. An alpha-pyrone (micropyrone, 7), the monoterpene rac-E-omega-oleoyloxylinalol (10), four known tremetones (9a-d), and the dimeric pyrone helipyrone (8) were also obtained. Arzanol inhibited HIV-1 replication in T cells and the release of pro-inflammatory cytokines in LPS-stimulated primary monocytes, qualifying as a novel plant-derived anti-inflammatory and antiviral chemotype worth further investigation.

  5. The Structure of Diagnostic and Statistical Manual of Mental Disorders (4th Edition, Text Revision) Personality Disorder Symptoms in a Large National Sample

    PubMed Central

    Trull, Timothy J.; Vergés, Alvaro; Wood, Phillip K.; Jahng, Seungmin; Sher, Kenneth J.

    2013-01-01

    We examined the latent structure underlying the criteria for DSM–IV–TR (American Psychiatric Association, 2000, Diagnostic and statistical manual of mental disorders (4th ed., text revision). Washington, DC: Author.) personality disorders in a large nationally representative sample of U.S. adults. Personality disorder symptom data were collected using a structured diagnostic interview from approximately 35,000 adults assessed over two waves of data collection in the National Epidemiologic Survey on Alcohol and Related Conditions. Our analyses suggested that a seven-factor solution provided the best fit for the data, and these factors were marked primarily by one or at most two personality disorder criteria sets. A series of regression analyses that used external validators tapping Axis I psychopathology, treatment for mental health problems, functioning scores, interpersonal conflict, and suicidal ideation and behavior provided support for the seven-factor solution. We discuss these findings in the context of previous studies that have examined the structure underlying the personality disorder criteria as well as the current proposals for DSM-5 personality disorders. PMID:22506626

  6. Interfacial Effects and Organization of Inorganic-Organic Composite Solids.

    DTIC Science & Technology

    1998-05-20

    SITU NMR STUDY OF THE HYDROTHERMAL SYNTHESIS OF TEMPLATE-MEDIATED MICROPOROUS ALUMINOPHOSPHATE MATERIALS, Conne M Gersrdin, Pnnccton Univ, Dept...quantitatively characterize the hydrothermal medium while the synthesis proceeds can yield to a better description of the different steps of the...Inorganic-Organic Composite Solids," focused on recent applications in materials synthesis that use structure-directing agents and self-assembly

  7. Social science to improve fuels management: a synthesis of research on assessing social acceptability of fuels treatments

    Treesearch

    Terry C. Daniel; Michael Valdiserri; Carrie R. Daniel; Pamela Jakes; Pamela Jakes; Susan Barro

    2005-01-01

    A series of syntheses were commissioned by the USDA Forest Service to aid in fuels mitigation project planning. This synthesis focuses on research for assessing the social acceptability of fuels treatments. The synthesis is structured around six important considerations for any social acceptability assessment: defining the fuels treatments being assessed; representing...

  8. The Synthesis of "N"-Benzyl-2-Azanorbornene via Aqueous Hetero Diels-Alder Reaction: An Undergraduate Project in Organic Synthesis and Structural Analysis

    ERIC Educational Resources Information Center

    Sauvage, Xavier; Delaude, Lionel

    2008-01-01

    The synthesis of "N"-benzyl-2-azanorbornene via aqueous hetero Diels-Alder reaction of cyclopentadiene and benzyliminium chloride formed in situ from benzylamine hydrochloride and formaldehyde is described. Characterization of the product was achieved by IR and NMR spectroscopies. The spectral data acquired are thoroughly discussed. Numerous…

  9. Hanford Site Environmental Restoration Program 1994 fiscal year work plan. Work breakdown structure 2.0: Revision 1

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    Site Management System (SMS) guidance requires a Fiscal Year Work Plan (FYWP) to be prepared for the Environmental Restoration (ER) Mission Area and all related programs. This revision is a complete update to cover the FY 1994 time period. This document describes the overall ER Missions Area and provides FYWP appendices for each of the following five program areas: Remedial Action (RA); Decontamination and Decommissioning (D&D); Project Management and Support (PM&S); Surveillance and Maintenance (S&M); and Disposal Facilities (DF).

  10. Frontiers in Chemistry.

    ERIC Educational Resources Information Center

    Joyce, Robert M., Ed.

    1980-01-01

    This article describes recent progress in chemical synthesis which depends on comparable advances in other areas of chemistry. Analysis and theories of chemical structure and reactions are determinants in progress in chemical synthesis and are described also. (Author/SA)

  11. Benzo[b]fluorenes via indanone dianion annulation: a short synthesis of prekinamycin.

    PubMed

    Birman, Vladimir B; Zhao, Zhufeng; Guo, Lei

    2007-03-29

    [structure: see text]. A rapid construction of benzo[b]fluorenones via reaction of 1-indanone dianions with phthalate diesters is described. Its utility is illustrated with a concise synthesis of prekinamycin.

  12. Challenges and Demands on Automated Software Revision

    NASA Technical Reports Server (NTRS)

    Bonakdarpour, Borzoo; Kulkarni, Sandeep S.

    2008-01-01

    In the past three decades, automated program verification has undoubtedly been one of the most successful contributions of formal methods to software development. However, when verification of a program against a logical specification discovers bugs in the program, manual manipulation of the program is needed in order to repair it. Thus, in the face of existence of numerous unverified and un- certified legacy software in virtually any organization, tools that enable engineers to automatically verify and subsequently fix existing programs are highly desirable. In addition, since requirements of software systems often evolve during the software life cycle, the issue of incomplete specification has become a customary fact in many design and development teams. Thus, automated techniques that revise existing programs according to new specifications are of great assistance to designers, developers, and maintenance engineers. As a result, incorporating program synthesis techniques where an algorithm generates a program, that is correct-by-construction, seems to be a necessity. The notion of manual program repair described above turns out to be even more complex when programs are integrated with large collections of sensors and actuators in hostile physical environments in the so-called cyber-physical systems. When such systems are safety/mission- critical (e.g., in avionics systems), it is essential that the system reacts to physical events such as faults, delays, signals, attacks, etc, so that the system specification is not violated. In fact, since it is impossible to anticipate all possible such physical events at design time, it is highly desirable to have automated techniques that revise programs with respect to newly identified physical events according to the system specification.

  13. Managing uncertainty - a qualitative study of surgeons' decision-making for one-stage and two-stage revision surgery for prosthetic hip joint infection.

    PubMed

    Moore, Andrew J; Blom, Ashley W; Whitehouse, Michael R; Gooberman-Hill, Rachael

    2017-04-12

    Approximately 88,000 primary hip replacements are performed in England and Wales each year. Around 1% go on to develop deep prosthetic joint infection. Between one-stage and two-stage revision arthroplasty best treatment options remain unclear. Our aims were to characterise consultant orthopaedic surgeons' decisions about performing either one-stage or two-stage revision surgery for patients with deep prosthetic infection (PJI) after hip arthroplasty, and to identify whether a randomised trial comparing one-stage with two-stage revision would be feasible. Semi-structured interviews were conducted with 12 consultant surgeons who perform revision surgery for PJI after hip arthroplasty at 5 high-volume National Health Service (NHS) orthopaedic departments in England and Wales. Surgeons were interviewed before the development of a multicentre randomised controlled trial. Data were analysed using a thematic approach. There is no single standardised surgical intervention for the treatment of PJI. Surgeons balance multiple factors when choosing a surgical strategy which include multiple patient-related factors, their own knowledge and expertise, available infrastructure and the infecting organism. Surgeons questioned whether it was appropriate that the two-stage revision remained the best treatment, and some surgeons' willingness to consider more one-stage revisions had increased over recent years and were influenced by growing evidence showing equivalence between surgical techniques, and local observations of successful one-stage revisions. Custom-made articulating spacers was a practice that enabled uncertainty to be managed in the absence of definitive evidence about the superiority of one surgical technique over the other. Surgeons highlighted the need for research evidence to inform practice and thought that a randomised trial to compare treatments was needed. Most surgeons thought that patients who they treated would be eligible for trial participation in instances where there was uncertainty about the best treatment option. Surgeons highlighted the need for evidence to support their choice of revision. Some surgeons' willingness to consider one-stage revision for infection had increased over time, largely influenced by evidence of successful one-stage revisions. Custom-made articulating spacers also enabled surgeons to manage uncertainty about the superiority of surgical techniques. Surgeons thought that a prospective randomised controlled trial comparing one-stage with two-stage joint replacement is needed and that randomisation would be feasible.

  14. Super-secondary structure peptidomimetics: design and synthesis of an α-α hairpin analogue

    PubMed Central

    Nevola, Laura; Rodriguez, Johanna M.; Thompson, Sam; Hamilton, Andrew D.

    2015-01-01

    The α-α helix motif presents key recognition domains in protein-protein and protein-oligonucleotide binding, and is one of the most common super-secondary structures. Herein we describe the design, synthesis and structural characterization of an α-α hairpin analogue based on a tetra-coordinated Pd(II) bis-(iminoisoquinoline) complex as a template for the display of two α-helix mimics. This approach is exemplified by the attachment of two biphenyl peptidomimetics to reproduce the side-chains of the i and i+4 residues of two helices. PMID:26052191

  15. Synthesis and characterization of organic-inorganic polymers from new methacrylate monomers and silane derivatives

    NASA Astrophysics Data System (ADS)

    Nicolescu, F. Adriana; Jerca, Victor V.; Albu, Ana M.; Vasilescu, D. Sorin; Vuluga, D. Mircea

    2009-09-01

    We report the synthesis of five new hybrid polymeric structures obtained by free radical copolymerization of some organic azo-based methacrylate monomers and 3-methacryloxypropyl trimethoxysilane (MEMO). The copolymers are soluble in common solvents like methylene chloride, chloroform, dichlorbenzene, dimethylsulfoxide, dimethylformamide. The copolymeric structures might be interesting from the point of view of nonlinear optical response due to a rich content in chromophoric units determined by H-NMR spectroscopy. The structures were also characterized by FT-IR spectroscopy, TGA and SEC analysis.

  16. Synthesis of aircraft structures using integrated design and analysis methods

    NASA Technical Reports Server (NTRS)

    Sobieszczanski-Sobieski, J.; Goetz, R. C.

    1978-01-01

    A systematic research is reported to develop and validate methods for structural sizing of an airframe designed with the use of composite materials and active controls. This research program includes procedures for computing aeroelastic loads, static and dynamic aeroelasticity, analysis and synthesis of active controls, and optimization techniques. Development of the methods is concerned with the most effective ways of integrating and sequencing the procedures in order to generate structural sizing and the associated active control system, which is optimal with respect to a given merit function constrained by strength and aeroelasticity requirements.

  17. Rational growth of Bi2S3 nanotubes from quasi-two-dimensional precursors.

    PubMed

    Ye, Changhui; Meng, Guowen; Jiang, Zhi; Wang, Yinhai; Wang, Guozhong; Zhang, Lide

    2002-12-25

    Synthesis of Bi2S3 nanotubes from rolling of the quasi-two-dimensional (2-D) layered precursor represents new progress in the synthetic approach and adds new members to the present inorganic fullerene family. These nanotubes display multiwalled structures that resemble that of a multiwalled carbon nanotube. The successful synthesis of Bi2S3 nanotubes highlights the feasibility of inorganic fullerene-like structures from other chemicals that possess layered crystalline structures, not only the well-known 2-D family, but possibly also those quasi-2-D members.

  18. Structure of Cu/Ni Nanowires Obtained by Matrix Synthesis

    NASA Astrophysics Data System (ADS)

    Zhigalina, O. M.; Doludenko, I. M.; Khmelenin, D. N.; Zagorskiy, D. L.; Bedin, S. A.; Ivanov, I. M.

    2018-05-01

    The structure of layered Cu/Ni nanowires obtained by template synthesis in 100-nm channels of track membranes has been investigated by transmission and scanning electron microscopy. The phase composition and main structural features of individual nanowires are determined. It is shown that nanowires consist of alternating Ni ( Fm3m) and Cu ( Fm3m) layers with grains up to 100 nm in size. It is found that nanowires contain also copper oxide crystallites up to 20 nm in size. The elemental composition of individual layers and their mutual arrangement are determined.

  19. The jumbo acetabular component for acetabular revision: Curtain Calls and Caveats.

    PubMed

    Lachiewicz, P F; Watters, T S

    2016-01-01

    The 'jumbo' acetabular component is now commonly used in acetabular revision surgery where there is extensive bone loss. It offers high surface contact, permits weight bearing over a large area of the pelvis, the need for bone grafting is reduced and it is usually possible to restore centre of rotation of the hip. Disadvantages of its use include a technique in which bone structure may not be restored, a risk of excessive posterior bone loss during reaming, an obligation to employ screw fixation, limited bone ingrowth with late failure and high hip centre, leading to increased risk of dislocation. Contraindications include unaddressed pelvic dissociation, inability to implant the component with a rim fit, and an inability to achieve screw fixation. Use in acetabulae with < 50% bone stock has also been questioned. Published results have been encouraging in the first decade, with late failures predominantly because of polyethylene wear and aseptic loosening. Dislocation is the most common complication of jumbo acetabular revisions, with an incidence of approximately 10%, and often mandates revision. Based on published results, a hemispherical component with an enhanced porous coating, highly cross-linked polyethylene, and a large femoral head appears to represent the optimum tribology for jumbo acetabular revisions. ©2016 The British Editorial Society of Bone & Joint Surgery.

  20. General synthesis and definitive structural identification of MN 4C 4 single-atom catalysts with tunable electrocatalytic activities

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fei, Huilong; Dong, Juncai; Feng, Yexin

    Single-atom catalysts (SACs) have recently attracted broad research interest as they combine the merits of both homogeneous and heterogeneous catalysts. Rational design and synthesis of SACs are of immense significance but have so far been plagued by the lack of a definitive correlation between structure and catalytic properties. Here, we report a general approach to a series of monodispersed atomic transition metals (for example, Fe, Co, Ni) embedded in nitrogen-doped graphene with a common MNsub>4C 4 moiety, identified by systematic X-ray absorption fine structure analyses and direct transmission electron microscopy imaging. The unambiguous structure determination allows density functional theoretical predictionmore » of MNsub>4C 4 moieties as efficient oxygen evolution catalysts with activities following the trend Ni > Co > Fe, which is confirmed by electrochemical measurements. Determination of atomistic structure and its correlation with catalytic properties represents a critical step towards the rational design and synthesis of precious or nonprecious SACs with exceptional atom utilization efficiency and catalytic activities.« less

  1. Structure-directing effects of ionic liquids in the ionothermal synthesis of metal-organic frameworks.

    PubMed

    Vaid, Thomas P; Kelley, Steven P; Rogers, Robin D

    2017-07-01

    Traditional synthesis of metal-organic frameworks (MOFs) involves the reaction of a metal-containing precursor with an organic linker in an organic solvent at an elevated temperature, in what is termed a 'solvothermal' reaction. More recently, many examples have been reported of MOF synthesis in ionic liquids (ILs), rather than an organic solvent, in 'ionothermal' reactions. The high concentration of both cations and anions in an ionic liquid allows for the formation of new MOF structures in which the IL cation or anion or both are incorporated into the MOF. Most commonly, the IL cation is included in the open cavities of the MOF, countering the anionic charge of the MOF framework itself and acting as a template around which the MOF structure forms. Ionic liquids can also serve other structure-directing roles, for example, when an IL containing a single enantiomer of a chiral anion leads to a homochiral MOF, even though the IL anion is not itself incorporated into the MOF. A comprehensive review of ionothermal syntheses of MOFs, and the structure-directing effects of the ILs, is given.

  2. Structural anatomy of telomere OB proteins.

    PubMed

    Horvath, Martin P

    2011-10-01

    Telomere DNA-binding proteins protect the ends of chromosomes in eukaryotes. A subset of these proteins are constructed with one or more OB folds and bind with G+T-rich single-stranded DNA found at the extreme termini. The resulting DNA-OB protein complex interacts with other telomere components to coordinate critical telomere functions of DNA protection and DNA synthesis. While the first crystal and NMR structures readily explained protection of telomere ends, the picture of how single-stranded DNA becomes available to serve as primer and template for synthesis of new telomere DNA is only recently coming into focus. New structures of telomere OB fold proteins alongside insights from genetic and biochemical experiments have made significant contributions towards understanding how protein-binding OB proteins collaborate with DNA-binding OB proteins to recruit telomerase and DNA polymerase for telomere homeostasis. This review surveys telomere OB protein structures alongside highly comparable structures derived from replication protein A (RPA) components, with the goal of providing a molecular context for understanding telomere OB protein evolution and mechanism of action in protection and synthesis of telomere DNA.

  3. Structural anatomy of telomere OB proteins

    PubMed Central

    Horvath, Martin P.

    2015-01-01

    Telomere DNA-binding proteins protect the ends of chromosomes in eukaryotes. A subset of these proteins are constructed with one or more OB folds and bind with G+T-rich single-stranded DNA found at the extreme termini. The resulting DNA-OB protein complex interacts with other telomere components to coordinate critical telomere functions of DNA protection and DNA synthesis. While the first crystal and NMR structures readily explained protection of telomere ends, the picture of how single-stranded DNA becomes available to serve as primer and template for synthesis of new telomere DNA is only recently coming into focus. New structures of telomere OB fold proteins alongside insights from genetic and biochemical experiments have made significant contributions towards understanding how protein-binding OB proteins collaborate with DNA-binding OB proteins to recruit telomerase and DNA polymerase for telomere homeostasis. This review surveys telomere OB protein structures alongside highly comparable structures derived from replication protein A (RPA) components, with the goal of providing a molecular context for understanding telomere OB protein evolution and mechanism of action in protection and synthesis of telomere DNA. PMID:21950380

  4. General synthesis and definitive structural identification of MN 4C 4 single-atom catalysts with tunable electrocatalytic activities

    DOE PAGES

    Fei, Huilong; Dong, Juncai; Feng, Yexin; ...

    2018-01-08

    Single-atom catalysts (SACs) have recently attracted broad research interest as they combine the merits of both homogeneous and heterogeneous catalysts. Rational design and synthesis of SACs are of immense significance but have so far been plagued by the lack of a definitive correlation between structure and catalytic properties. Here, we report a general approach to a series of monodispersed atomic transition metals (for example, Fe, Co, Ni) embedded in nitrogen-doped graphene with a common MNsub>4C 4 moiety, identified by systematic X-ray absorption fine structure analyses and direct transmission electron microscopy imaging. The unambiguous structure determination allows density functional theoretical predictionmore » of MNsub>4C 4 moieties as efficient oxygen evolution catalysts with activities following the trend Ni > Co > Fe, which is confirmed by electrochemical measurements. Determination of atomistic structure and its correlation with catalytic properties represents a critical step towards the rational design and synthesis of precious or nonprecious SACs with exceptional atom utilization efficiency and catalytic activities.« less

  5. Synthesis and morphogenesis of organic polymer materials with hierarchical structures in biominerals.

    PubMed

    Oaki, Yuya; Kijima, Misako; Imai, Hiroaki

    2011-06-08

    Synthesis and morphogenesis of polypyrrole (PPy) with hierarchical structures from nanoscopic to macroscopic scales have been achieved by using hierarchically organized architectures of biominerals. We adopted biominerals, such as a sea urchin spine and nacreous layer, having hierarchical architectures based on mesocrystals as model materials used for synthesis of an organic polymer. A sea urchin spine led to the formation of PPy macroscopic sponge structures consisting of nanosheets less than 100 nm in thickness with the mosaic interior of the nanoparticles. The morphologies of the resultant PPy hierarchical architectures can be tuned by the structural modification of the original biomineral with chemical and thermal treatments. In another case, a nacreous layer provided PPy porous nanosheets consisting of the nanoparticles. Conductive pathways were formed in these PPy hierarchical architectures. The nanoscale interspaces in the mesocrystal structures of biominerals are used for introduction and polymerization of the monomers, leading to the formation of hierarchically organized polymer architectures. These results show that functional organic materials with complex and nanoscale morphologies can be synthesized by using hierarchically organized architectures as observed in biominerals.

  6. An implementation of the distributed programming structural synthesis system (PROSSS)

    NASA Technical Reports Server (NTRS)

    Rogers, J. L., Jr.

    1981-01-01

    A method is described for implementing a flexible software system that combines large, complex programs with small, user-supplied, problem-dependent programs and that distributes their execution between a mainframe and a minicomputer. The Programming Structural Synthesis System (PROSSS) was the specific software system considered. The results of such distributed implementation are flexibility of the optimization procedure organization and versatility of the formulation of constraints and design variables.

  7. Diagnosing the Quality of High School Students' and Pre-Service Chemistry Teachers' Cognitive Structures in Organic Chemistry by Using Students' Generated Systemic Synthesis Questions

    ERIC Educational Resources Information Center

    Hrin, Tamara; Milenkovic, Dušica; Segedinac, Mirjana

    2018-01-01

    The importance of well elaborated cognitive structures in a science knowledge domain has been noted in many studies. Therefore, the main aim of this particular study was to employ a new diagrammatic assessment approach, students' generated systemic synthesis questions (SSynQs), to evaluate and compare the quality of high school students' and…

  8. 76 FR 82027 - Shipping Coordinating Committee; Notice of Committee Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-29

    ...; --Development of guidelines for use of fiber reinforced plastic (FRP) within ship structures; --Revision of... ships; --Air pollution and energy efficiency; --Reduction of GHG emissions from ships; --Consideration...

  9. Hydrothermal synthesis of a photovoltaic material based on CuIn0.5Ga0.5Se2

    NASA Astrophysics Data System (ADS)

    Castellanos Báez, Y. T.; Fuquen Peña, D. A.; Gómez-Cuaspud, J. A.; Vera-López, E.; Pineda-Triana, Y.

    2017-12-01

    The present work report, the synthesis and characterization of the CuIn0.5Ga0.5Se2 system (abbreviated CIGS), by the implementation of a hydrothermal route, in order to obtain a solid with appropriate properties in terms of surface, morphological and texture properties for potential applications in the design of photovoltaic cells. The synthesis was carried out using the corresponding stoichiometric quantities (Cu:In:Ga:Se 1:0.5:0.5:2), which were mixed in a Teflon vessel under stirring conditions. The homogeneous solution was treated in a steel autoclave at 300°C for 72 hours at the end of which the resulting material was characterized by X-Ray Diffraction (XRD) and Rietveld refinement. The results of the structural characterization allowed to confirm the obtaining of a chalcopyrite type structure, with a I-42 d (122) structure and cell parameters a=0.570, b=0.570, c=1.140nm, α=90, β=90, γ=90° oriented along (1 0 4) facet, detecting the presence of a secondary phases, related with CuInSe and CuIn metallic selenides, derived from synthesis process. The structural refinement allowing to validate the obtaining of a nanometric crystalline material (10-20nm) for potential applications in field of photovoltaic technology.

  10. FWP executive summaries, Basic Energy Sciences Materials Sciences Programs (SNL/NM)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Samara, G.A.

    1997-05-01

    The BES Materials Sciences Program has the central theme of Scientifically Tailored Materials. The major objective of this program is to combine Sandia`s expertise and capabilities in the areas of solid state sciences, advanced atomic-level diagnostics and materials synthesis and processing science to produce new classes of tailored materials as well as to enhance the properties of existing materials for US energy applications and for critical defense needs. Current core research in this program includes the physics and chemistry of ceramics synthesis and processing, the use of energetic particles for the synthesis and study of materials, tailored surfaces and interfacesmore » for materials applications, chemical vapor deposition sciences, artificially-structured semiconductor materials science, advanced growth techniques for improved semiconductor structures, transport in unconventional solids, atomic-level science of interfacial adhesion, high-temperature superconductors, and the synthesis and processing of nano-size clusters for energy applications. In addition, the program includes the following three smaller efforts initiated in the past two years: (1) Wetting and Flow of Liquid Metals and Amorphous Ceramics at Solid Interfaces, (2) Field-Structured Anisotropic Composites, and (3) Composition-Modulated Semiconductor Structures for Photovoltaic and Optical Technologies. The latter is a joint effort with the National Renewable Energy Laboratory. Separate summaries are given of individual research areas.« less

  11. Re-assessment of offshore structures using the revised HSE fatigue guidance

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stacey, A.; Sharp, J.V.

    1995-12-31

    The re-assessment of existing North Sea structures is an increasingly important issue as the age of platforms increases. Over 50 from a total of approximately 180 fixed installations in the UK sector are now over 15 years old. Fatigue damage has been the main reason for repairs to North Sea structures and the risk of this continues. The fatigue guidance of the Offshore Safety Division of the Health and Safety Executive (HSE) has recently been revised and published. Fundamental changes have been made to this guidance with several new recommendations including joint classification, basic design S-N curves for welded joints,more » the thickness effect, the effects of environment and the treatment of low and high stress ranges. To quantify the effects of the new guidance on the fatigue life assessment of offshore strictures, the HSE commissioned a study which included a deep water and a shallow water fixed steel structure and a twin-pontoon semi-submersible. These structures are typical of those operating in the North Sea. These were re-assessed with respect to fatigue lives and the results compared with predictions based on the 1990 guidance. The results and general conclusions are presented in this paper.« less

  12. BUGJEFF311.BOLIB (JEFF-3.1.1) and BUGENDF70.BOLIB (ENDF/B-VII.0) - Generation Methodology and Preliminary Testing of two ENEA-Bologna Group Cross Section Libraries for LWR Shielding and Pressure Vessel Dosimetry

    NASA Astrophysics Data System (ADS)

    Pescarini, Massimo; Sinitsa, Valentin; Orsi, Roberto; Frisoni, Manuela

    2016-02-01

    Two broad-group coupled neutron/photon working cross section libraries in FIDO-ANISN format, dedicated to LWR shielding and pressure vessel dosimetry applications, were generated following the methodology recommended by the US ANSI/ANS-6.1.2-1999 (R2009) standard. These libraries, named BUGJEFF311.BOLIB and BUGENDF70.BOLIB, are respectively based on JEFF-3.1.1 and ENDF/B-VII.0 nuclear data and adopt the same broad-group energy structure (47 n + 20 γ) of the ORNL BUGLE-96 similar library. They were respectively obtained from the ENEA-Bologna VITJEFF311.BOLIB and VITENDF70.BOLIB libraries in AMPX format for nuclear fission applications through problem-dependent cross section collapsing with the ENEA-Bologna 2007 revision of the ORNL SCAMPI nuclear data processing system. Both previous libraries are based on the Bondarenko self-shielding factor method and have the same AMPX format and fine-group energy structure (199 n + 42 γ) as the ORNL VITAMIN-B6 similar library from which BUGLE-96 was obtained at ORNL. A synthesis of a preliminary validation of the cited BUGLE-type libraries, performed through 3D fixed source transport calculations with the ORNL TORT-3.2 SN code, is included. The calculations were dedicated to the PCA-Replica 12/13 and VENUS-3 engineering neutron shielding benchmark experiments, specifically conceived to test the accuracy of nuclear data and transport codes in LWR shielding and radiation damage analyses.

  13. Psychometric properties of the Finnish version of the Women's Health Questionnaire.

    PubMed

    Katainen, Riina E; Engblom, Janne R; Vahlberg, Tero J; Polo-Kantola, Päivi

    2017-08-01

    The Women's Health Questionnaire (WHQ) is a validated and commonly used instrument for measuring climacteric-related symptoms. A revised version was previously developed. However, validation in a Finnish population is lacking. As it is important to use qualified instruments, we performed a validation study of the WHQ in a Finnish population. In all, 3,421 women, aged 41 to 54 years, formed the study population. In the original 36-item WHQ, the items were rated on a 1 to 4 scale and on a binary scale (0-1). The scaling of the revised 23-item WHQ was 0 to 100. We evaluated the psychometric properties (internal consistency, correlations between the symptom domains, factor structure, and sampling adequacy) in all three versions. For the 1 to 4 scale and on the revised version of the WHQ, the internal consistency was acceptable (the Cronbach's α coefficients >0.70) for most of the domains. On the binary scale, the majority of the coefficient values were below the acceptable level. The original symptom domains, especially those on the revised version, were recognizable from the factors in the exploratory factor analysis, but there were some limitations. The Kaiser-Meyer-Olkin values were high. The WHQ is a valid instrument for measuring climacteric-related symptoms in Finnish middle-aged women. The psychometric properties of the revised 23-item WHQ were as good or even better than those of the original 36-item WHQ. Thus, we encourage use of the revised version.

  14. Hierarchical macro-mesoporous structures in the system TiO{sub 2}-Al{sub 2}O{sub 3}, obtained by hydrothermal synthesis using Tween-20 as a directing agent

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Garcia-Benjume, M.L.; Espitia-Cabrera, M.I.; Contreras-Garcia, M.E., E-mail: eucontre@zeus.umich.mx

    2009-12-15

    Macro-mesoporous powders of titania, alumina, and mixed titania-20%alumina systems were obtained by hydrothermal synthesis employing surfactant Tween-20 as structural directing agent in order to promote the textural properties of titania. The effect of the alumina in the titania phase and on textural properties was analyzed. The obtained powders presented a macroporous channel structure that was characterized by X-ray diffractometry, scanning and transmission electron microscopy, N{sub 2} adsorption-desorption analysis, pore size distribution, Fourier transform infrared spectrometry, and thermogravimetric analysis. It was found that alumina content retarded the anatase phase crystallization and increased the Brunauer-Emmet-Teller surface area from 136 to 210 m{supmore » 2}/g. The powders calcined at 400 deg. C are thermally stable and possess an interconnected macro-mesoporous hierarchical structure; the results indicate that this synthesis can be employed to prepare mixed titania-alumina with good textural properties.« less

  15. Carbide-derived carbons - From porous networks to nanotubes and graphene

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Presser, V.; Heon, M.; Gogotsi, Y.

    2011-02-09

    Carbide-derived carbons (CDCs) are a large family of carbon materials derived from carbide precursors that are transformed into pure carbon via physical (e.g., thermal decomposition) or chemical (e.g., halogenation) processes. Structurally, CDC ranges from amorphous carbon to graphite, carbon nanotubes or graphene. For halogenated carbides, a high level of control over the resulting amorphous porous carbon structure is possible by changing the synthesis conditions and carbide precursor. The large number of resulting carbon structures and their tunability enables a wide range of applications, from tribological coatings for ceramics, or selective sorbents, to gas and electrical energy storage. In particular, themore » application of CDC in supercapacitors has recently attracted much attention. This review paper summarizes key aspects of CDC synthesis, properties, and applications. It is shown that the CDC structure and properties are sensitive to changes of the synthesis parameters. Understanding of processing–structure–properties relationships facilitates tuning of the carbon material to the requirements of a certain application.« less

  16. Harnessing cell-to-cell variations to probe bacterial structure and biophysics

    NASA Astrophysics Data System (ADS)

    Cass, Julie A.

    Advances in microscopy and biotechnology have given us novel insights into cellular biology and physics. While bacteria were long considered to be relatively unstructured, the development of fluorescence microscopy techniques, and spatially and temporally resolved high-throughput quantitative studies, have uncovered that the bacterial cell is highly organized, and its structure rigorously maintained. In this thesis I will describe our gateTool software, designed to harness cell-to-cell variations to probe bacterial structure, and discuss two exciting aspects of structure that we have employed gateTool to investigate: (i) chromosome organization and the cellular mechanisms for controlling DNA dynamics, and (ii) the study of cell wall synthesis, and how the genes in the synthesis pathway impact cellular shape. In the first project, we develop a spatial and temporal mapping of cell-cycle-dependent chromosomal organization, and use this quantitative map to discover that chromosomal loci segregate from midcell with universal dynamics. In the second project, I describe preliminary time- lapse and snapshot imaging analysis suggesting phentoypical coherence across peptidoglycan synthesis pathways.

  17. Rapid Synthesis and Formation Mechanism of Core-Shell-Structured La-Doped SrTiO3 with a Nb-Doped Shell

    PubMed Central

    Park, Nam-Hee; Akamatsu, Takafumi; Itoh, Toshio; Izu, Noriya; Shin, Woosuck

    2015-01-01

    To provide a convenient and practical synthesis process for metal ion doping on the surface of nanoparticles in an assembled nanostructure, core-shell-structured La-doped SrTiO3 nanocubes with a Nb-doped surface layer were synthesized via a rapid synthesis combining a rapid sol-precipitation and hydrothermal process. The La-doped SrTiO3 nanocubes were formed at room temperature by a rapid dissolution of NaOH pellets during the rapid sol-precipitation process, and the Nb-doped surface (shell) along with Nb-rich edges formed on the core nanocubes via the hydrothermal process. The formation mechanism of the core-shell-structured nanocubes and their shape evolution as a function of the Nb doping level were investigated. The synthesized core-shell-structured nanocubes could be arranged face-to-face on a SiO2/Si substrate by a slow evaporation process, and this nanostructured 10 μm thick thin film showed a smooth surface. PMID:28793420

  18. DNA-Encoded Solid-Phase Synthesis: Encoding Language Design and Complex Oligomer Library Synthesis.

    PubMed

    MacConnell, Andrew B; McEnaney, Patrick J; Cavett, Valerie J; Paegel, Brian M

    2015-09-14

    The promise of exploiting combinatorial synthesis for small molecule discovery remains unfulfilled due primarily to the "structure elucidation problem": the back-end mass spectrometric analysis that significantly restricts one-bead-one-compound (OBOC) library complexity. The very molecular features that confer binding potency and specificity, such as stereochemistry, regiochemistry, and scaffold rigidity, are conspicuously absent from most libraries because isomerism introduces mass redundancy and diverse scaffolds yield uninterpretable MS fragmentation. Here we present DNA-encoded solid-phase synthesis (DESPS), comprising parallel compound synthesis in organic solvent and aqueous enzymatic ligation of unprotected encoding dsDNA oligonucleotides. Computational encoding language design yielded 148 thermodynamically optimized sequences with Hamming string distance ≥ 3 and total read length <100 bases for facile sequencing. Ligation is efficient (70% yield), specific, and directional over 6 encoding positions. A series of isomers served as a testbed for DESPS's utility in split-and-pool diversification. Single-bead quantitative PCR detected 9 × 10(4) molecules/bead and sequencing allowed for elucidation of each compound's synthetic history. We applied DESPS to the combinatorial synthesis of a 75,645-member OBOC library containing scaffold, stereochemical and regiochemical diversity using mixed-scale resin (160-μm quality control beads and 10-μm screening beads). Tandem DNA sequencing/MALDI-TOF MS analysis of 19 quality control beads showed excellent agreement (<1 ppt) between DNA sequence-predicted mass and the observed mass. DESPS synergistically unites the advantages of solid-phase synthesis and DNA encoding, enabling single-bead structural elucidation of complex compounds and synthesis using reactions normally considered incompatible with unprotected DNA. The widespread availability of inexpensive oligonucleotide synthesis, enzymes, DNA sequencing, and PCR make implementation of DESPS straightforward, and may prompt the chemistry community to revisit the synthesis of more complex and diverse libraries.

  19. Mission-oriented requirements for updating MIL-H-8501: Calspan proposed structure and rationale

    NASA Technical Reports Server (NTRS)

    Chalk, C. R.; Radford, R. C.

    1985-01-01

    This report documents the effort by Arvin/Calspan Corporation to formulate a revision of MIL-H-8501A in terms of Mission-Oriented Flying Qualities Requirements for Military Rotorcraft. Emphasis is placed on development of a specification structure which will permit addressing Operational Missions and Flight Phases, Flight Regions, Classification of Required Operational Capability, Categorization of Flight Phases, and Levels of Flying Qualities. A number of definitions is established to permit addressing the rotorcraft state, flight envelopes, environments, and the conditions under which degraded flying qualities are permitted. Tentative requirements are drafted for Required Operational Capability Class 1. Also included is a Background Information and Users Guide for the draft specification structure proposed for the MIL-H-8501A revision. The report also contains a discussion of critical data gaps and attempts to prioritize these data gaps and to suggest experiments that should be performed to generate data needed to support formulation of quantitative design criteria for the additional Operational Capability Classes 2, 3, and 4.

  20. Integration of nursing assessment concepts into the medical entities dictionary using the LOINC semantic structure as a terminology model.

    PubMed

    Cieslowski, B J; Wajngurt, D; Cimino, J J; Bakken, S

    2001-01-01

    Recent investigations have tested the applicability of various terminology models for the representing nursing concepts including those related to nursing diagnoses, nursing interventions, and standardized nursing assessments as a prerequisite for building a reference terminology that supports the nursing domain. We used the semantic structure of Clinical LOINC (Logical Observations, Identifiers, Names, and Codes) as a reference terminology model to support the integration of standardized assessment terms from two nursing terminologies into the Medical Entities Dictionary (MED), the concept-oriented, metadata dictionary at New York Presbyterian Hospital. Although the LOINC semantic structure was used previously to represent laboratory terms in the MED, selected hierarchies and semantic slots required revisions in order to incorporate the nursing assessment concepts. This project was an initial step in integrating nursing assessment concepts into the MED in a manner consistent with evolving standards for reference terminology models. Moreover, the revisions provide the foundation for adding other types of standardized assessments to the MED.

  1. Integration of nursing assessment concepts into the medical entities dictionary using the LOINC semantic structure as a terminology model.

    PubMed Central

    Cieslowski, B. J.; Wajngurt, D.; Cimino, J. J.; Bakken, S.

    2001-01-01

    Recent investigations have tested the applicability of various terminology models for the representing nursing concepts including those related to nursing diagnoses, nursing interventions, and standardized nursing assessments as a prerequisite for building a reference terminology that supports the nursing domain. We used the semantic structure of Clinical LOINC (Logical Observations, Identifiers, Names, and Codes) as a reference terminology model to support the integration of standardized assessment terms from two nursing terminologies into the Medical Entities Dictionary (MED), the concept-oriented, metadata dictionary at New York Presbyterian Hospital. Although the LOINC semantic structure was used previously to represent laboratory terms in the MED, selected hierarchies and semantic slots required revisions in order to incorporate the nursing assessment concepts. This project was an initial step in integrating nursing assessment concepts into the MED in a manner consistent with evolving standards for reference terminology models. Moreover, the revisions provide the foundation for adding other types of standardized assessments to the MED. PMID:11825165

  2. The Forensic Symptoms Inventory-Revised (FSI-R Adults): Measurement and Structural Invariance Across Gender and Age Groups.

    PubMed

    van Horn, Joan E

    2018-06-01

    This article investigates the measurement and structural invariance of a newly developed self-report questionnaire, the Forensic Symptoms Inventory-Revised, aimed at measuring eight cognitive, emotional, and behavioral deficits (aggression, lack of social support, problematic substance use, lack of concentration, anger, poor self-regulation, impulsivity, and sexual problems) among adult forensic outpatients. The sample consisted of 716 outpatients (603 males, 113 females) with a mean age of 38.19 (SD = 12.47). Multi-Group Confirmatory Factor Analyses supported the measurement and structural invariance with respect to gender and age groups (18-23 years and ≥24 years). Between-group comparisons revealed that, compared to females, male outpatients reported more substance related problems, as well as incapacities to control verbal and/or physical aggression. Compared to adults, young adults displayed more inadequate self-regulation skills and reported more social support. These findings may promote the formulation of gender- and age-specific treatment goals.

  3. Reverse Micelle Based Synthesis of Microporous Materials in Microgravity

    NASA Technical Reports Server (NTRS)

    Dutta, Prabir K.

    2001-01-01

    Microporous materials include a large group of solids of varying chemical composition as well as porosity. These materials are characterized by channels and cavities of molecular dimensions. The framework structure is made up of interconnecting T-O-T' bonds, where T and T' can be Si, Al, P, Ga, Fe, Co, Zn, B and a host of other elements. Materials with Si-O-Al bonding in the framework are called zeolites and are extensively used in many applications. Ion-exchange properties of these materials are exploited in the consumer and environmental industries. Chemical and petroleum industries use zeolites as catalysts in hydrocarbon transform ations. Synthesis of new microporous frameworks has led to the development of new technologies, and thus considerable effort worldwide is expended in their discovery. Microporous materials are typically made under hydrothermal conditions. Influence of nature of starting reactants, structure directing agents, pH, temperature, and aging all have profound influence on the synthesis process. This is primarily because the most interesting open frameworks are not necessarily the stable structures in the reaction medium. Thus, the discovery of new frameworks is often tied to finding the right composition and synthesis conditions that allow for kinetic stabilization of the structure. This complexity of the synthesis process and limited understanding of it has made it difficult to develop directed is of microporous materials and most advances in this field have been made by trial and error. The basic issues in crystal growth of these materials include: (1) Nature of the nucleation process; (2) Molecular structure and assembly of nuclei; (3) Growth of nuclei into crystals; (4) Morphology control; and (5) Transformation of frameworks into other structures. The NASA-funded research described in this paper focuses on all the above issues and has been described in several publications. We present the highlights of our program, especially with the focus on possible experiments in microgravity.

  4. Polymer-directed synthesis of metal oxide-containing nanomaterials for electrochemical energy storage

    NASA Astrophysics Data System (ADS)

    Mai, Yiyong; Zhang, Fan; Feng, Xinliang

    2013-12-01

    Metal oxide-containing nanomaterials (MOCNMs) of controllable structures at the nano-scale have attracted considerable interest because of their great potential applications in electrochemical energy storage devices, such as lithium-ion batteries (LIBs) and supercapacitors. Among many structure-directing agents, polymers and macromolecules, including block copolymers (BCPs) and graphene, exhibit distinct advantages in the template-assisted synthesis of MOCNMs. In this feature article, we introduce the controlled preparation of MOCNMs employing BCPs and graphene as structure-directing agents. Typical synthetic strategies are presented for the control of structures and sizes as well as the improvement of physical properties and electrochemical performance of MOCNMs in LIBs and supercapacitors.

  5. Polymer-directed synthesis of metal oxide-containing nanomaterials for electrochemical energy storage.

    PubMed

    Mai, Yiyong; Zhang, Fan; Feng, Xinliang

    2014-01-07

    Metal oxide-containing nanomaterials (MOCNMs) of controllable structures at the nano-scale have attracted considerable interest because of their great potential applications in electrochemical energy storage devices, such as lithium-ion batteries (LIBs) and supercapacitors. Among many structure-directing agents, polymers and macromolecules, including block copolymers (BCPs) and graphene, exhibit distinct advantages in the template-assisted synthesis of MOCNMs. In this feature article, we introduce the controlled preparation of MOCNMs employing BCPs and graphene as structure-directing agents. Typical synthetic strategies are presented for the control of structures and sizes as well as the improvement of physical properties and electrochemical performance of MOCNMs in LIBs and supercapacitors.

  6. NOTE: On the need to revise the arm structure in stylized anthropomorphic phantoms in lateral photon irradiation geometry

    NASA Astrophysics Data System (ADS)

    Lee, Choonsik; Lee, Choonik; Lee, Jai-Ki

    2006-11-01

    Distributions of radiation absorbed dose within human anatomy have been estimated through Monte Carlo radiation transport techniques implemented for two different classes of computational anthropomorphic phantoms: (1) mathematical equation-based stylized phantoms and (2) tomographic image-based voxel phantoms. Voxel phantoms constructed from tomographic images of real human anatomy have been actively developed since the late 1980s to overcome the anatomical approximations necessary with stylized phantoms, which themselves have been utilized since the mid 1960s. However, revisions of stylized phantoms have also been pursued in parallel to the development of voxel phantoms since voxel phantoms (1) are initially restricted to the individual-specific anatomy of the person originally imaged, (2) must be restructured on an organ-by-organ basis to conform to reference individual anatomy and (3) cannot easily represent very fine anatomical structures and tissue layers that are thinner than the voxel dimensions of the overall phantom. Although efforts have been made to improve the anatomic realism of stylized phantoms, most of these efforts have been limited to attempts to alter internal organ structures. Aside from the internal organs, the exterior shapes, and especially the arm structures, of stylized phantoms are also far from realistic descriptions of human anatomy, and may cause dosimetry errors in the calculation of organ-absorbed doses for external irradiation scenarios. The present study was intended to highlight the need to revise the existing arm structure within stylized phantoms by comparing organ doses of stylized adult phantoms with those from three adult voxel phantoms in the lateral photon irradiation geometry. The representative stylized phantom, the adult phantom of the Oak Ridge National Laboratory (ORNL) series and two adult male voxel phantoms, KTMAN-2 and VOXTISS8, were employed for Monte Carlo dose calculation, and data from another voxel phantom, VIP-Man, were obtained from literature sources. The absorbed doses for lungs, oesophagus, liver and kidneys that could be affected by arm structures in the lateral irradiation geometry were obtained for both classes of phantoms in lateral monoenergetic photon irradiation geometries. As expected, those organs in the ORNL phantoms received apparently higher absorbed doses than those in the voxel phantoms. The overestimation is mainly attributed to the relatively poor representation of the arm structure in the ORNL phantom in which the arm bones are embedded within the regions describing the phantom's torso. The results of this study suggest that the overestimation of organ doses, due to unrealistic arm representation, should be taken into account when stylized phantoms are employed for equivalent or effective dose estimates, especially in the case of an irradiation scenario with dominating lateral exposure. For such a reason, the stylized phantom arm structure definition should be revised in order to obtain more realistic evaluations.

  7. Geologic framework, structure, and hydrogeologic characteristics of the Knippa Gap area in eastern Uvalde and western Medina Counties, Texas

    USGS Publications Warehouse

    Clark, Allan K.; Pedraza, Diana E.; Morris, Robert R.

    2013-01-01

    By using data that were compiled and collected for this study and previous studies, a revised map was constructed depicting the geologic framework, structure, and hydrogeologic characteristics of the Knippa Gap area in eastern Uvalde and western Medina Counties, Tex. The map also shows the interpreted structural dip directions and interpreted location of a structural low (trough) in the area known as the Knippa Gap.

  8. Investigation of innovative synthesis of biologically active compounds on the basis of newly developed reactions.

    PubMed

    Honda, Toshio

    2012-01-01

    Synthesis of biologically active compounds, including natural products and pharmaceutical agents, is an important and interesting research area since the large structural diversity and complexity of bioactive compounds make them an important source of leads and scaffolds in drug discovery and development. Many structurally and also biologically interesting compounds, including marine natural products, have been isolated from nature and have also been prepared on the basis of a computational design for the purpose of developing medicinal chemistry. In order to obtain a wide variety of derivatives of biologically active compounds from the viewpoint of medicinal chemistry, it is essential to establish efficient synthetic procedures for desired targets. Newly developed reactions should also be used for efficient synthesis of desired compounds. Thus, recent progress in the synthesis of biologically active compounds by focusing on the development of new reactions is summarized in this review article.

  9. Utilization of plasmas for graphene synthesis

    NASA Astrophysics Data System (ADS)

    Shashurin, Alexey; Keidar, Michael

    2013-10-01

    Graphene is a one-atom-thick planar sheet of carbon atoms that are densely packed in a honeycomb crystal lattice. Grapheen has tremendous range of potential applications ranging from high-speed transistors to electrochemical energy storage devices and biochemical sensors. Methods of graphene synthesis include mechanical exfoliation, epitaxial growth on SiC, CVD and colloidal suspensions. In this work the utilization of plasmas in synthesis process is considered. Types of carbonaceous structures produced by the anodic arc and regions of their synthesis were studied. Ultimate role of substrate temperature and transformations occurring with various carbonaceous structures generated in plasma discharge were considered. Formation of graphene film on copper substrate was detected at temperatures around the copper melting point. The film was consisted of several layers graphene flakes having typical sizes of about 200 nm. Time required for crystallization of graphene on externally heated substrates was determined. This work was supported by National Science Foundation (NSF Grant No. CBET-1249213).

  10. High-throughput continuous hydrothermal synthesis of nanomaterials (part II): unveiling the as-prepared CexZryYzO2-δ phase diagram.

    PubMed

    Quesada-Cabrera, Raul; Weng, Xiaole; Hyett, Geoff; Clark, Robin J H; Wang, Xue Z; Darr, Jawwad A

    2013-09-09

    High-throughput continuous hydrothermal flow synthesis was used to manufacture 66 unique nanostructured oxide samples in the Ce-Zr-Y-O system. This synthesis approach resulted in a significant increase in throughput compared to that of conventional batch or continuous hydrothermal synthesis methods. The as-prepared library samples were placed into a wellplate for both automated high-throughput powder X-ray diffraction and Raman spectroscopy data collection, which allowed comprehensive structural characterization and phase mapping. The data suggested that a continuous cubic-like phase field connects all three Ce-Zr-O, Ce-Y-O, and Y-Zr-O binary systems together with a smooth and steady transition between the structures of neighboring compositions. The continuous hydrothermal process led to as-prepared crystallite sizes in the range of 2-7 nm (as determined by using the Scherrer equation).

  11. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Neal, J.T.; Magorian, T.R.; Ahmad, S.

    This report revises the original report that was published in 1980. Some of the topics covered in the earlier report were provisional and it is now practicable to reexamine them using new or revised geotechnical data and that obtained from SPR cavern operations, which involves 16 new caverns. Revised structure maps and sections show interpretative differences as compared with the 1980 report and more definition in the dome shape and caprock structural contours, especially a major southeast-northwest trending anomalous zone. The original interpretation was of westward tilt of the dome, this revision shows a tilt to the southeast, consistent withmore » other gravity and seismic data. This interpretation refines the evaluation of additional cavern space, by adding more salt buffer and allowing several more caverns. Additional storage space is constrained on this nearly full dome because of low-lying peripheral wetlands, but 60 MMBBL or more of additional volume could be gained in six or more new caverns. Subsidence values at Bryan Mound are among the lowest in the SPR system, averaging about 11 mm/yr (0.4 in/yr), but measurement and interpretation issues persist, as observed values are about the same as survey measurement accuracy. Periodic flooding is a continuing threat because of the coastal proximity and because peripheral portions of the site are at elevations less than 15 ft. This threat may increase slightly as future subsidence lowers the surface, but the amount is apt to be small. Caprock integrity may be affected by structural features, especially the faulting associated with anomalous zones. Injection wells have not been used extensively at Bryan Mound, but could be a practicable solution to future brine disposal needs. Environmental issues center on the areas of low elevation that are below 15 feet above mean sea level: the coastal proximity and lowland environment combined with the potential for flooding create conditions that require continuing surveillance.« less

  12. Confirmatory factor analysis of the Child Oral Health Impact Profile (Korean version).

    PubMed

    Cho, Young Il; Lee, Soonmook; Patton, Lauren L; Kim, Hae-Young

    2016-04-01

    Empirical support for the factor structure of the Child Oral Health Impact Profile (COHIP) has not been fully established. The purposes of this study were to evaluate the factor structure of the Korean version of the COHIP (COHIP-K) empirically using confirmatory factor analysis (CFA) based on the theoretical framework and then to assess whether any of the factors in the structure could be grouped into a simpler single second-order factor. Data were collected through self-reported COHIP-K responses from a representative community sample of 2,236 Korean children, 8-15 yr of age. Because a large inter-factor correlation of 0.92 was estimated in the original five-factor structure, the two strongly correlated factors were combined into one factor, resulting in a four-factor structure. The revised four-factor model showed a reasonable fit with appropriate inter-factor correlations. Additionally, the second-order model with four sub-factors was reasonable with sufficient fit and showed equal fit to the revised four-factor model. A cross-validation procedure confirmed the appropriateness of the findings. Our analysis empirically supported a four-factor structure of COHIP-K, a summarized second-order model, and the use of an integrated summary COHIP score. © 2016 Eur J Oral Sci.

  13. Analysis on pseudo excitation of random vibration for structure of time flight counter

    NASA Astrophysics Data System (ADS)

    Wu, Qiong; Li, Dapeng

    2015-03-01

    Traditional computing method is inefficient for getting key dynamical parameters of complicated structure. Pseudo Excitation Method(PEM) is an effective method for calculation of random vibration. Due to complicated and coupling random vibration in rocket or shuttle launching, the new staging white noise mathematical model is deduced according to the practical launch environment. This deduced model is applied for PEM to calculate the specific structure of Time of Flight Counter(ToFC). The responses of power spectral density and the relevant dynamic characteristic parameters of ToFC are obtained in terms of the flight acceptance test level. Considering stiffness of fixture structure, the random vibration experiments are conducted in three directions to compare with the revised PEM. The experimental results show the structure can bear the random vibration caused by launch without any damage and key dynamical parameters of ToFC are obtained. The revised PEM is similar with random vibration experiment in dynamical parameters and responses are proved by comparative results. The maximum error is within 9%. The reasons of errors are analyzed to improve reliability of calculation. This research provides an effective method for solutions of computing dynamical characteristic parameters of complicated structure in the process of rocket or shuttle launching.

  14. Precursor routes to quaternary intermetallics: Synthesis, crystal structure, and physical properties of clathrate-II Cs8Na16Al24Si112

    NASA Astrophysics Data System (ADS)

    Wei, Kaya; Dong, Yongkwan; Nolas, George S.

    2016-05-01

    A new quaternary clathrate-II composition, Cs8Na16Al24Si112, was synthesized by kinetically controlled thermal decomposition (KCTD) employing both NaSi and NaAlSi as the precursors and CsCl as a reactive flux. The crystal structure and composition of Cs8Na16Al24Si112 were investigated using both Rietveld refinement and elemental analysis, and the temperature dependent transport properties were investigated. Our results indicate that KCTD with multiple precursors is an effective method for the synthesis of multinary inorganic phases that are not easily accessible by traditional solid-state synthesis or crystal growth techniques.

  15. Aminosilane functionalizations of mesoporous oxidized silicon for oligonucleotide synthesis and detection

    PubMed Central

    De Stefano, Luca; Oliviero, Giorgia; Amato, Jussara; Borbone, Nicola; Piccialli, Gennaro; Mayol, Luciano; Rendina, Ivo; Terracciano, Monica; Rea, Ilaria

    2013-01-01

    Direct solid phase synthesis of peptides and oligonucleotides (ONs) requires high chemical stability of the support material. In this work, we have investigated the passivation ability of porous oxidized silicon multilayered structures by two aminosilane compounds, 3-aminopropyltriethoxysilane and 3-aminopropyldimethylethoxysilane (APDMES), for optical label-free ON biosensor fabrication. We have also studied by spectroscopic reflectometry the hybridization between a 13 bases ON, directly grown on the aminosilane modified porous oxidized silicon by in situ synthesis, and its complementary sequence. Even if the results show that both devices are stable to the chemicals (carbonate/methanol) used, the porous silica structure passivated by APDMES reveals higher functionalization degree due to less steric hindrance of pores. PMID:23536541

  16. Cyclic azole-homologated peptides from Marine sponges.

    PubMed

    Molinski, Tadeusz F

    2017-12-19

    This review discusses the chemistry of cyclic azole-homologated peptides (AHPs) from the marine sponges, Theonella swinhoei, other Theonella species, Calyx spp. and Plakina jamaicensis. The origin, distribution of AHPs and molecular structure elucidations of AHPs are described followed by their biosynthesis, bioactivity, and synthetic efforts towards their total synthesis. Reports of partial and total synthesis of AHPs extend beyond peptide coupling reactions and include creative construction of the non-proteinogenic amino acid components, mainly the homologated heteroaromatic and α-keto-β-amino acids. A useful conclusion is drawn regarding AHPs: despite their rarity, exotic structures and the potent protease inhibitory properties of some members, their synthesis is under-developed and beckons solutions for outstanding problems towards their efficient assembly.

  17. Molecular Modeling in Drug Design for the Development of Organophosphorus Antidotes/Prophylactics.

    DTIC Science & Technology

    1986-06-01

    multidimensional statistical QSAR analysis techniques to suggest new structures for synthesis and evaluation. C. Application of quantum chemical techniques to...compounds for synthesis and testing for antidotal potency. E. Use of computer-assisted methods to determine the steric constraints at the active site...modeling techniques to model the enzyme acetylcholinester-se. H. Suggestion of some novel compounds for synthesis and testing for reactivating

  18. Raman Spectrometer for the Characterization of Advanced Materials and Nanomaterials

    DTIC Science & Technology

    2016-04-18

    Capannelli, F. Canepa, M. Napoletano, M.R. Cimberle, et al., Synthesis and magnetic characterization of Ni nanoparticles and Ni nanoparticles in...Hennig, R.D. Robinson, Unintended phosphorus doping of nickel nanoparticles during synthesis with TOP: a discovery through structural analysis...Davar, Z. Fereshteh, M. Salavati-Niasari, Nanoparticles Ni and NiO: Synthesis , characterization and magnetic properties, J. Alloys Compd. 476 (2009) 797–801.

  19. Acta Aeronautica et Astronautica Sinica,

    DTIC Science & Technology

    1983-07-28

    substructural analysis in modal synthesis - two improved substructural assembling techniques 49 9-node quadrilateral isoparametric element 64 Application of laser...Time from Service Data, J. Aircraft, Vol. 15, No. 11, 1978. 48 MULTI-LEVEL SUBSTRUCTURAL ANALYSIS IN MODAL SYNTHESIS -- TWO IMPROVED SUBSTRUCTURAL...34 Modal Synthesis in Structural Dynamic Analysis ," Naching Institute of Aeronautics and Astronautics, 1979. 62a 8. Chang Te-wen, "Free-Interface Modal

  20. Fe-based Fischer Tropsch Synthesis of biomass-derived syngas: Effect of synthesis method

    Treesearch

    Khiet Mai; Thomas Elder; Les Groom; James J. Spivey

    2015-01-01

    Two 100Fe/4Cu/4K/6Zn catalysts were prepared using two different methods: coprecipitation or impregnation methods. The effect of the preparation methods on the catalyst structure, catalytic properties, and the conversion of biomass-derived syngas via Fischer–Tropsch synthesis was investigated. Syngas was derived from gasifying Southern pine woodchips and had the...

  1. The Structure-Preserving Constraint and the Universal Base Hypothesis

    ERIC Educational Resources Information Center

    Kravif, Diane

    1973-01-01

    Revised version of a paper supported by a National Science Foundation graduate fellowship. The universal base hypothesis states that all natural languages utilize the same base component in their transformational grammars. (DD)

  2. Correction to the Alfven-Lawson criterion for relativistic electron beams

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dodin, I. Y.; Fisch, N. J.

    2006-10-15

    The Alfven-Lawson criterion for relativistic electron beams is revised. The parameter range is found, in which a stationary beam can carry arbitrarily large current, regardless of its transverse structure.

  3. Standardization of the Hare Psychopathy Checklist-Revised in a Spanish prison sample.

    PubMed

    Moltó, J; Poy, R; Torrubia, R

    2000-01-01

    This investigation examined the reliability, validity, and factor structure of the Hare Psychopathy Checklist-Revised (PCL-R) in male adult Spanish prison populations (n = 117). The interrater reliability and internal consistency coefficients were high, and similar to those obtained in other countries. This data provides support for the homogeneity and unidimensionality of the psychopathy construct in Spanish male prison samples. The analysis of factor structure also replicated the two factor solution of previous studies. The two factors showed different patterns of intercorrelations with several self-report measures of personality, demographic, and criminal history variables, which confirmed the construct validity of PCL-R. The results confirm the psychometric properties of the PCL-R as a measure of psychopathy in Spanish male inmates, and suggest that psychopathy is a construct also observed in Southern European countries.

  4. Factor Structure of Scores from the Conners’ Rating Scales–Revised Among Nepali Children

    PubMed Central

    Pendergast, Laura L.; Vandiver, Beverly J.; Schaefer, Barbara A.; Cole, Pamela M.; Murray-Kolb, Laura M.; Christian, Parul

    2014-01-01

    This study used exploratory and confirmatory factor analyses to examine the structures of scores from the Conners’ Teacher and Parent Rating Scales–Revised (CTRS-R and CPRS-R, respectively; Conners, 1997). The scales were administered to 1,835 parents and 1,387 teachers of children in Nepal's Sarlahi district – a region where no other measures of child psychopathology have been studied. With a Nepali sample, the findings indicate that reduced two factor models for the Conners’ scales are superior to the models identified in the scale development research. The hyperactivity and inattention factors were comparable to what has been identified in prior research, while other factors (e.g., social problems) differed substantially. Implications for use of the Conners’ scales in Nepal and cross cultural issues in the assessment of ADHD symptoms are discussed. PMID:25574454

  5. Usher Syndrome Type III: Revised Genomic Structure of the USH3 Gene and Identification of Novel Mutations

    PubMed Central

    Fields, Randall R.; Zhou, Guimei; Huang, Dali; Davis, Jack R.; Möller, Claes; Jacobson, Samuel G.; Kimberling, William J.; Sumegi, Janos

    2002-01-01

    Usher syndrome type III is an autosomal recessive disorder characterized by progressive sensorineural hearing loss, vestibular dysfunction, and retinitis pigmentosa. The disease gene was localized to 3q25 and recently was identified by positional cloning. In the present study, we have revised the structure of the USH3 gene, including a new translation start site, 5′ untranslated region, and a transcript encoding a 232–amino acid protein. The mature form of the protein is predicted to contain three transmembrane domains and 204 residues. We have found four new disease-causing mutations, including one that appears to be relatively common in the Ashkenazi Jewish population. We have also identified mouse (chromosome 3) and rat (chromosome 2) orthologues, as well as two human paralogues on chromosomes 4 and 10. PMID:12145752

  6. [Difference analysis among majors in medical parasitology exam papers by test item bank proposition].

    PubMed

    Jia, Lin-Zhi; Ya-Jun, Ma; Cao, Yi; Qian, Fen; Li, Xiang-Yu

    2012-04-30

    The quality index among "Medical Parasitology" exam papers and measured data for students in three majors from the university in 2010 were compared and analyzed. The exam papers were formed from the test item bank. The alpha reliability coefficients of the three exam papers were above 0.70. The knowledge structure and capacity structure of the exam papers were basically balanced. But the alpha reliability coefficients of the second major was the lowest, mainly due to quality of test items in the exam paper and the failure of revising the index of test item bank in time. This observation demonstrated that revising the test items and their index in the item bank according to the measured data can improve the quality of test item bank proposition and reduce the difference among exam papers.

  7. A bias-adjusted evidence synthesis of RCT and observational data: the case of total hip replacement.

    PubMed

    Schnell-Inderst, Petra; Iglesias, Cynthia P; Arvandi, Marjan; Ciani, Oriana; Matteucci Gothe, Raffaella; Peters, Jaime; Blom, Ashley W; Taylor, Rod S; Siebert, Uwe

    2017-02-01

    Evaluation of clinical effectiveness of medical devices differs in some aspects from the evaluation of pharmaceuticals. One of the main challenges identified is lack of robust evidence and a will to make use of experimental and observational studies (OSs) in quantitative evidence synthesis accounting for internal and external biases. Using a case study of total hip replacement to compare the risk of revision of cemented and uncemented implant fixation modalities, we pooled treatment effect estimates from OS and RCTs, and simplified existing methods for bias-adjusted evidence synthesis to enhance practical application. We performed an elicitation exercise using methodological and clinical experts to determine the strength of beliefs about the magnitude of internal and external bias affecting estimates of treatment effect. We incorporated the bias-adjusted treatment effects into a generalized evidence synthesis, calculating both frequentist and Bayesian statistical models. We estimated relative risks as summary effect estimates with 95% confidence/credibility intervals to capture uncertainty. When we compared alternative approaches to synthesizing evidence, we found that the pooled effect size strongly depended on the inclusion of observational data as well as on the use bias-adjusted estimates. We demonstrated the feasibility of using observational studies in meta-analyses to complement RCTs and incorporate evidence from a wider spectrum of clinically relevant studies and healthcare settings. To ensure internal validity, OS data require sufficient correction for confounding and selection bias, either through study design and primary analysis, or by applying post-hoc bias adjustments to the results. © 2017 The Authors. Health Economics published by John Wiley & Sons, Ltd. © 2017 The Authors. Health Economics published by John Wiley & Sons, Ltd.

  8. Synthesis of Optimal Constant-Gain Positive-Real Controllers for Passive Systems

    NASA Technical Reports Server (NTRS)

    Mao, Y.; Kelkar, A. G.; Joshi, S. M.

    1999-01-01

    This paper presents synthesis methods for the design of constant-gain positive real controllers for passive systems. The results presented in this paper, in conjunction with the previous work by the authors on passification of non-passive systems, offer a useful synthesis tool for the design of passivity-based robust controllers for non-passive systems as well. Two synthesis approaches are given for minimizing an LQ-type performance index, resulting in optimal controller gains. Two separate algorithms, one for each of these approaches, are given. The synthesis techniques are demonstrated using two numerical examples: control of a flexible structure and longitudinal control of a fighter aircraft.

  9. Microwave-assisted synthesis of medicinally relevant indoles.

    PubMed

    Patil, S A; Patil, R; Miller, D D

    2011-01-01

    Indoles represent an important structural class in medicinal chemistry with broad spectrum of biological activities. The synthesis of indoles, therefore, has attracted enormous attention from synthetic chemists. Microwave methods for the preparation of indole analogs have been developed to speed up the synthesis, therefore, microwave assisted organic synthesis (MAOS) in controlled conditions is an invaluable technique for medicinal chemistry. In this review, indole forming classical reactions such as Fischer, Madelung, Bischler-Mohlau, Batcho-Leimgruber, Hemetsberger-Knittel, Graebe-Ullmann, Diels-Alder and Wittig type reactions using microwave radiation has been summarized. In addition, metal mediated cyclizations along with solid phase synthesis of indoles have been discussed. © 2011 Bentham Science Publishers Ltd.

  10. Macro-cellular silica foams: synthesis during the natural creaming process of an oil-in-water emulsion.

    PubMed

    Sen, T; Tiddy, G J T; Casci, J L; Anderson, M W

    2003-09-07

    The room-temperature synthesis of a macro-mesoporous silica material during the natural creaming process of an oil-in-water emulsion is reported. The material has 3-dimensional interconnected macropores with a strut-like structure similar to meso-cellular silica foams with mesoporous walls of worm-hole structure. The material has very high surface area (approximately 800 m2 g(-1)) with narrow mesopore size distribution.

  11. Structure and Reactivity of Perfluorinated Annulenes and their Relatives.

    DTIC Science & Technology

    1986-11-22

    out before the beginning of the AFOSR grant) Dailey, W. P.; Lemal, D. M. " Perfluorotropilidene Valence Isomers and the Perfluorotropylium Ion", J. Am... Perfluorosemibullvalene : Synthesis of 1 -Bromo-1,2-dichlorodifluoroethane", 1986 Raymond, J. F., "Toward the Synthesis of a Polyfluorinated Bicyclo[2...A176 954 STRUCTURE AND REACTIVITY OF PERFLUORINATED ANNULENES 1l/ AND THEIR RELRTIVES(U) DARTMOUTH COLL HRNOVER N N DEPT OF CHEMISTRY D M LEMAL 22

  12. Controlled Synthesis and Magnetic Properties of Uniform Hierarchical Polyhedral α-Fe2O3 Particles

    NASA Astrophysics Data System (ADS)

    Long, Nguyen Viet; Yang, Yong; Thi, Cao Minh; Phuc, Le Hong; Nogami, Masayuki

    2017-06-01

    The controlled synthesis of uniform hierarchical polyhedral iron (Fe) micro-/nanoscale oxide particles with the α-Fe2O3 structure is presented. The hierarchical polyhedral iron oxide particles were synthesized by modified polyol methods with sodium borohydride as a powerful and efficient reducing agent. A critical heat treatment process used during the synthesis allowed for the interesting formation of α-Fe2O3 hematite with a micro-/nanoscale structure. The structure and weak ferromagnetism of the α-Fe2O3 particles were investigated by x-ray diffraction with whole pattern fitting and Rietveld refinement, scanning electron microscopy, and by vibrating sample magnetometry. The as-prepared α-Fe2O3 particles and the three dimensional models presented have promising practical applications for energy storage and conversion in batteries, capacitors, and fuel cells, and related spintronic devices and technologies.

  13. Polycatenar Ligand Control of the Synthesis and Self-Assembly of Colloidal Nanocrystals.

    PubMed

    Diroll, Benjamin T; Jishkariani, Davit; Cargnello, Matteo; Murray, Christopher B; Donnio, Bertrand

    2016-08-24

    Hydrophobic colloidal nanocrystals are typically synthesized and manipulated with commercially available ligands, and surface functionalization is therefore typically limited to a small number of molecules. Here, we report the use of polycatenar ligands derived from polyalkylbenzoates for the direct synthesis of metallic, chalcogenide, pnictide, and oxide nanocrystals. Polycatenar molecules, branched structures bearing diverging chains in which the terminal substitution pattern, functionality, and binding group can be independently modified, offer a modular platform for the development of ligands with targeted properties. Not only are these ligands used for the direct synthesis of monodisperse nanocrystals, but nanocrystals coated with polycatenar ligands self-assemble into softer bcc superlattices that deviate from conventional harder close-packed structures (fcc or hcp) formed by the same nanocrystals coated with commercial ligands. Self-assembly experiments demonstrate that the molecular structure of polycatenar ligands encodes interparticle spacings and attractions, engineering self-assembly, which is tunable from hard sphere to soft sphere behavior.

  14. Ribozyme-catalysed RNA synthesis using triplet building blocks.

    PubMed

    Attwater, James; Raguram, Aditya; Morgunov, Alexey S; Gianni, Edoardo; Holliger, Philipp

    2018-05-15

    RNA-catalyzed RNA replication is widely believed to have supported a primordial biology. However, RNA catalysis is dependent upon RNA folding, and this yields structures that can block replication of such RNAs. To address this apparent paradox we have re-examined the building blocks used for RNA replication. We report RNA-catalysed RNA synthesis on structured templates when using trinucleotide triphosphates (triplets) as substrates, catalysed by a general and accurate triplet polymerase ribozyme that emerged from in vitro evolution as a mutualistic RNA heterodimer. The triplets cooperatively invaded and unraveled even highly stable RNA secondary structures, and support non-canonical primer-free and bidirectional modes of RNA synthesis and replication. Triplet substrates thus resolve a central incongruity of RNA replication, and here allow the ribozyme to synthesise its own catalytic subunit '+' and '-' strands in segments and assemble them into a new active ribozyme. © 2018, Attwater et al.

  15. Synthesis of Ultra-incompressible sp 3 -Hybridized Carbon Nitride with 1:1 Stoichiometry

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stavrou, Elissaios; Lobanov, Sergey; Dong, Huafeng

    Search of materials with C-N composition hold a great promise in creating materials which would rival diamond hardness due to the very strong and relatively low-ionic C-N bond. Early experimental and theoretical works on C-N compounds were based on structural similarity with binary A 3B 4 structural types; however, the synthesis of C 3N 4 remains elusive. Here we explored an unbiased synthesis from the elemental materials at high pressures and temperatures. Using in situ synchrotron X-ray diffraction and Raman spectroscopy we demonstrate the synthesis of highly incompressible Pnnm CN compound with sp 3 hybridized carbon above 55 GPa andmore » 7000 K. This result is supported by first principles evolutionary search, which finds that Pnnm CN is the most stable compound above 10.9 GPa. On pressure release below 6 GPa the synthesized CN compound amorphizes reattaining its 1:1 stoichiometry as confirmed by Energy-Dispersive X-ray Spectroscopy. Here, this work underscores the importance of understanding of novel high-pressure chemistry rules and it opens a new route for synthesis of superhard materials.« less

  16. Synthesis of Ultra-incompressible sp 3 -Hybridized Carbon Nitride with 1:1 Stoichiometry

    DOE PAGES

    Stavrou, Elissaios; Lobanov, Sergey; Dong, Huafeng; ...

    2016-10-11

    Search of materials with C-N composition hold a great promise in creating materials which would rival diamond hardness due to the very strong and relatively low-ionic C-N bond. Early experimental and theoretical works on C-N compounds were based on structural similarity with binary A 3B 4 structural types; however, the synthesis of C 3N 4 remains elusive. Here we explored an unbiased synthesis from the elemental materials at high pressures and temperatures. Using in situ synchrotron X-ray diffraction and Raman spectroscopy we demonstrate the synthesis of highly incompressible Pnnm CN compound with sp 3 hybridized carbon above 55 GPa andmore » 7000 K. This result is supported by first principles evolutionary search, which finds that Pnnm CN is the most stable compound above 10.9 GPa. On pressure release below 6 GPa the synthesized CN compound amorphizes reattaining its 1:1 stoichiometry as confirmed by Energy-Dispersive X-ray Spectroscopy. Here, this work underscores the importance of understanding of novel high-pressure chemistry rules and it opens a new route for synthesis of superhard materials.« less

  17. A Better Understanding of Protein Structure and Function by the Synthesis and Incorporation of Selenium- and Tellurium Containing Tryptophan Analogs

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Helmey, Sherif Samir; Rice, Ambrose Eugene; Hatch, Duane Michael

    Unnatural heavy metal-containing amino acid analogs have shown to be very important in the analysis of protein structure, using methods such as X-ray crystallography, mass spectroscopy, and NMR spectroscopy. Synthesis and incorporation of selenium-containing methionine analogs has already been shown in the literature however with some drawbacks due to toxicity to host organisms. Thus synthesis of heavy metal tryptophan analogs should prove to be more effective since the amino acid tryptophan is naturally less abundant in many proteins. For example, bioincorporation of β-seleno[3,2-b]pyrrolyl-L-alanine ([4,5]SeTrp) and β-selenolo[2,3-b]pyrrolyl-L-alanine ([6,7]SeTrp) has been shown in the following proteins without structural or catalytic perturbations: humanmore » annexin V, barstar, and dihydrofolate reductase. The reported synthesis of these Se-containing analogs is currently not efficient for commercial purposes. Thus a more efficient, concise, high-yield synthesis of selenotryptophan, as well as the corresponding, tellurotryptophan, will be necessary for wide spread use of these unnatural amino acid analogs. This research will highlight our progress towards a synthetic route of both [6,7]SeTrp and [6,7]TeTrp, which ultimately will be used to study the effect on the catalytic activity of Lignin Peroxidase (LiP).« less

  18. Library design practices for success in lead generation with small molecule libraries.

    PubMed

    Goodnow, R A; Guba, W; Haap, W

    2003-11-01

    The generation of novel structures amenable to rapid and efficient lead optimization comprises an emerging strategy for success in modern drug discovery. Small molecule libraries of sufficient size and diversity to increase the chances of discovery of novel structures make the high throughput synthesis approach the method of choice for lead generation. Despite an industry trend for smaller, more focused libraries, the need to generate novel lead structures makes larger libraries a necessary strategy. For libraries of a several thousand or more members, solid phase synthesis approaches are the most suitable. While the technology and chemistry necessary for small molecule library synthesis continue to advance, success in lead generation requires rigorous consideration in the library design process to ensure the synthesis of molecules possessing the proper characteristics for subsequent lead optimization. Without proper selection of library templates and building blocks, solid phase synthesis methods often generate molecules which are too heavy, too lipophilic and too complex to be useful for lead optimization. The appropriate filtering of virtual library designs with multiple computational tools allows the generation of information-rich libraries within a drug-like molecular property space. An understanding of the hit-to-lead process provides a practical guide to molecular design characteristics. Examples of leads generated from library approaches also provide a benchmarking of successes as well as aspects for continued development of library design practices.

  19. The effect of variation in physical properties of porous bioactive glass on the expression and maintenance of the osteoblastic phenotype

    NASA Astrophysics Data System (ADS)

    Effah Kaufmann, Elsie Akosua Biraa

    Revision surgery to replace failed hip implants is a significant health care issue that is expected to escalate as life expectancy increases. A major goal of revision surgery is to reconstruct femoral intramedullary bone-stock loss. To address this problem of bone loss, grafting techniques are widely used. Although fresh autografts remain the optimal material for all forms of surgery seeking to restore structural integrity to the skeleton, it is evident that the supply of such tissue is limited. In recent years, calcium phosphate ceramics have been studied as alternatives to autografts and allografts. The significant limitations associated with the use of biological and synthetic grafts have led to a growing interest in the in vitro synthesis of bone tissue. The approach is to synthesize bone tissue in vitro with the patient's own cells, and use this tissue for the repair of bony defects. Various substrates including metals, polymers, calcium phosphate ceramics and bioactive glasses, have been seeded with osteogenic cells. The selection of bioactive glass in this study is based on the fact that this material has shown an intense beneficial biological effect which has not been reproduced by other biomaterials. Even though the literature provides extensive data on the effect of pore size and porosity on in vivo bone tissue ingrowth into porous materials for joint prosthesis fixation, the data from past studies cannot be applied to the use of bioactive glass as a substrate for the in vitro synthesis of bone tissue. First, unlike the in vivo studies in the literature, this research deals with the growth of bone tissue in vitro. Second, unlike the implants used in past studies, bioactive glass is a degradable and resorbable material. Thus, in order to establish optimal substrate characteristics (porosity and pore size) for bioactive glass, it was important to study these parameters in an in vitro model. We synthesized porous bioactive glass substrates (BG) with varying pore sizes and porosity and determined the effect of substrate properties on the expression and maintenance of the osteoblastic phenotype, using an in vitro culture of osteoblast-like cells. Our data showed that porous bioactive glass substrates support the proliferation and maturation of osteoblast-like cells. Within the conditions of the experiment, we also found that at a given porosity of 44% the pore size of bioactive glass neither directs nor modulates the in vitro expression of the osteoblastic phenotype. On the other hand, at an average pore size of 92 mum, when cultures are maintained for 14 days, cell activity is greatly affected by the substrate porosity. As the porosity increases from 35% to 59%, osteoblast activity is adversely affected. (Abstract shortened by UMI.)

  20. Structural and Biochemical Characterization of Chlamydia trachomatis Hypothetical Protein CT263 Supports That Menaquinone Synthesis Occurs through the Futalosine Pathway*

    PubMed Central

    Barta, Michael L.; Thomas, Keisha; Yuan, Hongling; Lovell, Scott; Battaile, Kevin P.; Schramm, Vern L.; Hefty, P. Scott

    2014-01-01

    The obligate intracellular human pathogen Chlamydia trachomatis is the etiological agent of blinding trachoma and sexually transmitted disease. Genomic sequencing of Chlamydia indicated this medically important bacterium was not exclusively dependent on the host cell for energy. In order for the electron transport chain to function, electron shuttling between membrane-embedded complexes requires lipid-soluble quinones (e.g. menaquionone or ubiquinone). The sources or biosynthetic pathways required to obtain these electron carriers within C. trachomatis are poorly understood. The 1.58Å crystal structure of C. trachomatis hypothetical protein CT263 presented here supports a role in quinone biosynthesis. Although CT263 lacks sequence-based functional annotation, the crystal structure of CT263 displays striking structural similarity to 5′-methylthioadenosine nucleosidase (MTAN) enzymes. Although CT263 lacks the active site-associated dimer interface found in prototypical MTANs, co-crystal structures with product (adenine) or substrate (5′-methylthioadenosine) indicate that the canonical active site residues are conserved. Enzymatic characterization of CT263 indicates that the futalosine pathway intermediate 6-amino-6-deoxyfutalosine (kcat/Km = 1.8 × 103 m−1 s−1), but not the prototypical MTAN substrates (e.g. S-adenosylhomocysteine and 5′-methylthioadenosine), is hydrolyzed. Bioinformatic analyses of the chlamydial proteome also support the futalosine pathway toward the synthesis of menaquinone in Chlamydiaceae. This report provides the first experimental support for quinone synthesis in Chlamydia. Menaquinone synthesis provides another target for agents to combat C. trachomatis infection. PMID:25253688

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