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Sample records for hindered agostic c-h-m

  1. Simulating the Agostic Interaction in Electron-deficient (16-e) Group ...

    African Journals Online (AJOL)

    A large number of theoretical studies have focused on understanding the molecular features of the agostic interaction in various kinds of molecular environments. However, there is a lack of electronic structure information about the agostic interaction in electron-deficient group (VI)ML6 organometallic complexes. In this ...

  2. Thermochemistry and Molecular Structure of a Remarkable Agostic Interaction in a Heterobifunctional Ruthenium-Boron Complex

    Science.gov (United States)

    Conley, Brian L.; Williams, Travis J.

    2010-01-01

    A boron-pendant ruthenium species forms a unique agostic methyl bridge between the boron and ruthenium atoms in the presence of a ligating solvent, acetonitrile. NMR inversion-recovery experiments enable measurement of the activation and equilibrium thermochemistry for formation of the agostic bridge. The mechanism for bridge formation involves displacement of an acetonitrile ligand; thus, this is a rare example of a case where an agostic C—H ligand competitively displaces another tight-binding ligand from a coordinatively saturated complex. Characterization of this complex gives unique insights into development of C—H activation catalysis based on this ligand-metal bifunctional motif. PMID:20088526

  3. The Agost Basin (Betic Cordillera, Alicante province, Spain): a pull-apart basin involving salt tectonics

    Science.gov (United States)

    Martín-Martín, Manuel; Estévez, Antonio; Martín-Rojas, Ivan; Guerrera, Francesco; Alcalá, Francisco J.; Serrano, Francisco; Tramontana, Mario

    2017-08-01

    The Agost Basin is characterized by a Miocene-Quaternary shallow marine and continental infilling controlled by the evolution of several curvilinear faults involving salt tectonics derived from Triassic rocks. From the Serravallian on, the area experienced a horizontal maximum compression with a rotation of the maximum stress axis from E-W to N-S. The resulting deformation gave rise to a strike-slip fault whose evolution is characterized progressively by three stages: (1) stepover/releasing bend with a dextral motion of blocks; (2) very close to pure horizontal compression; and (3) restraining bend with a sinistral movement of blocks. In particular, after an incipient fracturing stage, faults generated a pull-apart basin with terraced sidewall fault and graben subzones developed in the context of a dextral stepover during the lower part of late Miocene p.p. The occurrence of Triassic shales and evaporites played a fundamental role in the tectonic evolution of the study area. The salty material flowed along faults during this stage generating salt walls in root zones and salt push-up structures at the surface. During the purely compressive stage (middle part of late Miocene p.p.) the salt walls were squeezed to form extrusive mushroom-like structures. The large amount of clayish and salty material that surfaced was rapidly eroded and deposited into the basin, generating prograding fan clinoforms. The occurrence of shales and evaporites (both in the margins of the basin and in the proper infilling) favored folding of basin deposits, faulting, and the formation of rising blocks. Later, in the last stage (upper part of late Miocene p.p.), the area was affected by sinistral restraining conditions and faults must have bent to their current shape. The progressive folding of the basin and deformation of margins changed the supply points and finally caused the end of deposition and the beginning of the current erosive systems. On the basis of the interdisciplinary results

  4. The missing entry in the agostic-anagostic series: Rh(I)-η(1)-C interactions in P(CH)P pincer complexes.

    Science.gov (United States)

    Lepetit, Christine; Poater, Jordi; Alikhani, M Esmail; Silvi, Bernard; Canac, Yves; Contreras-García, Julia; Solà, Miquel; Chauvin, Remi

    2015-03-16

    The missing entry, namely, the "C-anagostic" or η(1)-C interaction, closing the agostic-anagostic series of metal-CH(aryl) interactions is found in a bis(amidiniophosphine) P(CH)P pincer rhodium complex. The three entries, namely, agostic η(2)-(C,H), anagostic (related to hydrogen bonding, thus recoined here as "H-anagostic"), and C-anagostic interactions, are unambiguously characterized by electron localization function (ELF) topological analysis. Other theoretical tools such as noncovalent interaction (NCI) analysis and multicenter electron delocalization indices (MCIs) support the ELF characterization. A η(2)-(C,H) agostic interaction is evidenced by a disynaptic V(C,H) or trisynaptic V(M,C,H) ELF basin with a significant quantum topological atoms in molecules (QTAIM) atomic contribution of the metal M and a large covariance (in absolute value) with the metal core basin C(M). The C-anagostic η(1)-C interaction is characterized by a disynaptic V(M,C) basin, a weak covariance (in absolute value) of V(C,H) and C(M) populations, and a negligible QTAIM atomic contribution of M to V(C,H). The relevance of these ELF signatures is evidenced in a selected series of related rhodium and osmium complexes.

  5. Thorium and Uranium Hydride Phosphorus and Arsenic Bearing Molecules with Single and Double Actinide-Pnictogen and Bridged Agostic Hydrogen Bonds.

    Science.gov (United States)

    Andrews, Lester; Cho, Han-Gook; Thanthiriwatte, K Sahan; Dixon, David A

    2017-03-06

    Thorium atoms from laser ablation react with phosphine during condensation in excess argon to produce two new infrared absorptions at 1467.2 and 1436.6 cm(-1) near weak bands for ThH and ThH2, which increase on annealing to 25 and 30 K, indicating spontaneous reactions. Analogous experiments with uranium produced two similar bands at 1473.4 and 1456.7 cm(-1) above UH at 1423.8 cm(-1) and another absorption at 1388.2 cm(-1). Electronic structure calculations at the coupled cluster CCSD(T) for Th and density functional theory calculations for U as well as their proximity to other actinide hydride absorptions support assignments of these bands to the simplest molecules HP═ThH2, HP═UH2, and PH2-UH. Arsine gave the analogous products HAs═ThH2, HAs═UH2, and AsH2-UH. The HE═AnH2 molecules (E = P, As; An = Th, U) have strong agostic An-H(E) interactions with H-E-An angles in the range of 60-64°. The calculated agostic bond distances are 9% to 12% longer than terminal single An-H bonds, which suggests that these strong agostic bonds can be considered as bridge bonds since similar relationships are found for the dibridged M2H6 molecules (M = Al, Ga, In). The NBO analysis and the molecular orbitals show the presence of a σ and a π bond for HE═AnH2 molecules that are heavily polarized with most of the density on the P or As.

  6. A Cobalt(I) Pincer Complex with an η(2) -C(aryl)-H Agostic Bond: Facile C-H Bond Cleavage through Deprotonation, Radical Abstraction, and Oxidative Addition.

    Science.gov (United States)

    Murugesan, Sathiyamoorthy; Stöger, Berthold; Pittenauer, Ernst; Allmaier, Günter; Veiros, Luis F; Kirchner, Karl

    2016-02-24

    The synthesis and reactivity of a Co(I) pincer complex [Co(ϰ(3) P,CH,P-P(CH)P(NMe) -iPr)(CO)2](+) featuring an η(2)-C(aryl)-H agostic bond is described. This complex was obtained by protonation of the Co(I) complex [Co(PCP(NMe) -iPr)(CO)2]. The Co(III) hydride complex [Co(PCP(NMe) -iPr)(CNtBu)2(H)](+) was obtained upon protonation of [Co(PCP(NMe) -iPr)(CNtBu)2]. Three ways to cleave the agostic C-H bond are presented. First, owing to the acidity of the agostic proton, treatment with pyridine results in facile deprotonation (C-H bond cleavage) and reformation of [Co(PCP(NMe) -iPr)(CO)2]. Second, C-H bond cleavage is achieved upon exposure of [Co(ϰ(3)P,CH,P-P(CH)P(NMe) -iPr)(CO)2](+) to oxygen or TEMPO to yield the paramagnetic Co(II) PCP complex [Co(PCP(NMe) -iPr)(CO)2](+). Finally, replacement of one CO ligand in [Co(ϰ(3) P,CH,P-P(CH)P(NMe) -iPr)(CO)2](+) by CNtBu promotes the rapid oxidative addition of the agostic η(2) -C(aryl)-H bond to give two isomeric hydride complexes of the type [Co(PCP(NMe) -iPr)(CNtBu)(CO)(H)](+). © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Survivors of Downsizing: Helpful and Hindering Experiences

    Science.gov (United States)

    Amundson, Norman E.; Borgen, William A.; Jordan, Sharalyn; Erlebach, Anne C.

    2004-01-01

    Thirty-one downsizing survivors from both the private and public sector were interviewed to determine incidents that either helped or hindered their transition through 1 or more organizational downsizings. A critical incident technique was used to analyze and organize the data around themes that emerged, themes were represented by both positive…

  8. Polyelectrolytes with sterically hindered anionic charges

    Energy Technology Data Exchange (ETDEWEB)

    Yeh, T.F.; Liu, H.; Okamoto, Y.; Lee, H.S.; Skotheim, T.A. (Polytechnic Inst. of Brooklyn, NY (USA); Brookhaven National Lab., Upton, NY (USA))

    1989-01-01

    The central problem in the development of single phase polymer electrolytes with exclusive cation conduction has been inadequate ion mobility due to extensive ion pairing between the mobile cation and the covalently attached anion. We have developed a new class of single ion conducting polymers, or polyelectrolytes, based on highly flexible polysiloxane backbones and attached sterically hindered phenolate anions. The combination of a highly delocalized and sterically enclosed anionic charged separation and consequently enhanced cation mobility. 10 refs., 2 figs.

  9. Non-Markovianity hinders Quantum Darwinism

    Science.gov (United States)

    Galve, Fernando; Zambrini, Roberta; Maniscalco, Sabrina

    2016-01-01

    We investigate Quantum Darwinism and the emergence of a classical world from the quantum one in connection with the spectral properties of the environment. We use a microscopic model of quantum environment in which, by changing a simple system parameter, we can modify the information back flow from environment into the system, and therefore its non-Markovian character. We show that the presence of memory effects hinders the emergence of classical objective reality, linking these two apparently unrelated concepts via a unique dynamical feature related to decoherence factors.

  10. Hindered Glymes for Graphite-Compatible Electrolytes.

    Science.gov (United States)

    Shanmukaraj, Devaraj; Grugeon, Sylvie; Laruelle, Stephane; Armand, Michel

    2015-08-24

    Organic carbonate mixtures are used almost exclusively as lithium battery electrolyte solvents. The linear compounds (dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate) act mainly as thinner for the more viscous and high-melting ethylene carbonate but are the least stable component and have low flash points; these are serious handicaps for lifetime and safety. Polyethers (glymes) are useful co-solvents, but all formerly known representatives solvate Li(+) strongly enough to co-intercalate in the graphite negative electrode and exfoliate it. We have put forward a new electrolyte composition comprising a polyether to which a bulky tert-butyl group is attached ("hindered glyme"), thus completely preventing co-intercalation while maintaining good conductivity. This alkyl-carbonate-free electrolyte shows remarkable cycle efficiency of the graphite electrode, not only at room temperature, but also at 50 and 70 °C in the presence of lithium bis(fluorosulfonimide). The two-ethylene-bridge hindered glyme has a high boiling point and a flash point of 80 °C, a considerable advantage for safety. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Hydrolyzable polyureas bearing hindered urea bonds.

    Science.gov (United States)

    Ying, Hanze; Cheng, Jianjun

    2014-12-10

    Hydrolyzable polymers are widely used materials that have found numerous applications in biomedical, agricultural, plastic, and packaging industrials. They usually contain ester and other hydrolyzable bonds, such as anhydride, acetal, ketal, or imine, in their backbone structures. Here, we report the first design of hydrolyzable polyureas bearing dynamic hindered urea bonds (HUBs) that can reversibly dissociate to bulky amines and isocyanates, the latter of which can be further hydrolyzed by water, driving the equilibrium to facilitate the degradation of polyureas. Polyureas bearing 1-tert-butyl-1-ethylurea bonds that show high dynamicity (high bond dissociation rate), in the form of either linear polymers or cross-linked gels, can be completely degraded by water under mild conditions. Given the simplicity and low cost for the production of polyureas by simply mixing multifunctional bulky amines and isocyanates, the versatility of the structures, and the tunability of the degradation profiles of HUB-bearing polyureas, these materials are potentially of very broad applications.

  12. Overlearned responses hinder S-R binding.

    Science.gov (United States)

    Moeller, Birte; Frings, Christian

    2017-01-01

    Two mechanisms that are important for human action control are the integration of individual action plans (see Hommel, Müsseler, Aschersleben, & Prinz, 2001) and the automatization of overlearned actions to familiar stimuli (see Logan, 1988). In the present study, we analyzed the influence of automatization on action plan integration. Integration with pronunciation responses were compared for response incompatible word and nonword stimuli. Stimulus-response binding effects were observed for nonwords. In contrast, words that automatically triggered an overlearned pronunciation response were not integrated with pronunciation of a different word. That is, automatized response retrieval hindered binding effects regarding the retrieving stimulus and a new response. The results are a first indication of the way that binding and learning processes interact, and might also be a first step to understanding the more complex interdependency of the processes responsible for stimulus-response binding in action control and stimulus-response associations in learning research. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  13. Search for Unified Action Mechanism of Hindered Amine Light Stabilizers

    National Research Council Canada - National Science Library

    大勝, 靖一

    2008-01-01

      Hindered amine light stabilizers (HALS) possess many functions unlike other additives and are frequently used to extend the service life of polymeric materials, but show particular compatibility with certain other additives...

  14. Biostratigraphy and assemblage evolution in Planktic Foraminifera across the Cretaceous-Paleogene transition in low latitude, northern and southern Tethys realm: El Kef GSSP, Elles (Tunisia) and Agost, Caravaca (Betic Cordillera, Spain)

    Science.gov (United States)

    Gallala, N.; Zaghbib-Turki, D.; Turki, M. M.; Arenillas, I.; Arz, J. A.; Molina, E.

    2009-04-01

    The detailed planktic foraminiferal biostratigraphic and quantitative study from the Cretaceous-Paleogene (K-Pg) transition interval of the most expanded and continuous sections located in Spanish (Agost, Caravaca) and Tunisian sections (El Kef and Ellès), allows us to establish the zonation and subzonation of this interval and to distinguish four Acme-stages across the K/Pg transition interval of these low latitude sections. The uppermost Maastrichtian in Tunisian and Spanish sections, is characterized by standard planktic foraminiferal zones: Abathomphalus mayaroensis subdivided into Plummerita hantkeninoides Subzones. This index species is absent at middle and high-latitude twice in Atlantic and Antarctic oceans. Consequently, this species is considered to be restricted to the tropical and subtropical deep seawater. The lower Danian is characterized by Guembelitria cretacea, Parvularugoglobigerina eugubina, and Parasubbotina pseudobulloides biozones. The Guembelitria cretacea Zone was subdivided into the Hedbergella holmdelensis and Parvularugoglobigerina longiapertura Subzones; the Parvularugoglobigerina eugubina Zone into the Parvularugoglobigerina sabina and Eoglobigerina simplicissima Subzones; and the Parasubbotina pseudobulloides Zone into the Eoglobigerina trivialis and Subbotina triloculinoides Subzones. These zones and subzones are less expanded at the Caravaca and Agost sections than in Tunisian sections: El Kef (Global Stratotype Section and Point for the K/Pg) and Ellès, but it is sufficiently expanded to analyze correctly the planktic foraminiferal assemblage evolution across the K-Pg transition. Across this transition, at the Tethys area, we have identified four Acme-stages: Acme-stage 0: is typical of the upper Maastrichtian interval is dominated by cosmopolitan species dwelling surface and intermediate seawater. Acme-stage 1: is typical of the G. cretacea Zone and is dominated by Guembelitria species belonging to "Cretaceous survivors" species

  15. Does genetic diversity hinder parasite evolution in social insect colonies?

    DEFF Research Database (Denmark)

    Hughes, William Owen Hamar; Boomsma, Jacobus Jan

    2006-01-01

    Polyandry is often difficult to explain because benefits of the behaviour have proved elusive. In social insects, polyandry increases the genetic diversity of workers within a colony and this has been suggested to improve the resistance of the colony to disease. Here we examine the possible impact...... hinder the ability of parasites to adapt while cycling within social insect colonies....

  16. What Helps and Hinders Workers in Managing Change

    Science.gov (United States)

    Butterfeld, Lee D.; Borgen, William A.; Amundson, Norman E.; Erlebach, Anne C.

    2010-01-01

    This research responds to calls for increased understanding of workers' experiences of their work and work contexts. Informed by positive psychology, this study focused on a seldom-studied subset of working individuals who self-identified as doing well with change affecting their work and on strategies that helped or hindered them in doing well,…

  17. Reducing school related factors hindering girl-child equality of ...

    African Journals Online (AJOL)

    The problem addressed in this paper is the school based factor such as curriculum bias, sex stereotyping in learning materials, teachers and student factors which hinder girl-child access to quality education. It is observed that these factors impede the girl-child equality of access to quality education. To solve this problem it ...

  18. Challenges hindering female participation in politics as expressed ...

    African Journals Online (AJOL)

    The study challenges hindering female participation in politics as expressed by female politicians in the federal capital territory, Abuja, Nigeria. The research design adopted for this study was descriptive survey. The respondents were 210 female politicians selected from six Area Councils of the FCT using a proportionate ...

  19. SYNTHESIS AND PROPERTIES OF STERICALLY HINDERED WATER SOLUBLE PORPHYRINE

    Directory of Open Access Journals (Sweden)

    Yu. V. Ishkov

    2014-12-01

    Full Text Available 5,10,15,20-(2-methoxy-3-quinolinylporphyrine, which was a mixture of atropisomers, was obtained by condensation of 2-methoxyquinoline-3-carbaldehyde with pyrrole in propionic acid. Quaternization of nitrogen atoms of peripheric substituents in this compound lead to water soluble sterically hindered porphyrine.

  20. Hindered bacterial mobility in porous media flow enhances dispersion

    Science.gov (United States)

    Dehkharghani, Amin; Waisbord, Nicolas; Dunkel, Jörn; Guasto, Jeffrey

    2017-11-01

    Swimming bacteria live in porous environments characterized by dynamic fluid flows, where they play a crucial role in processes ranging from the bioremediation to the spread of infections. We study bacterial transport in a quasi-two-dimensional porous microfluidic device, which is complemented by Langevin simulations. The cell trajectories reveal filamentous patterns of high cell concentration, which result from the accumulation of bacteria in the high-shear regions of the flow and their subsequent advection. Moreover, the effective diffusion coefficient of the motile bacteria is severely hindered in the transverse direction to the flow due to decorrelation of the cells' persistent random walk by shear-induced rotation. The hindered lateral diffusion has the surprising consequence of strongly enhancing the longitudinal bacterial transport through a dispersion effect. These results demonstrate the significant role of the flow and geometry in bacterial transport through porous media with potential implications for understanding ecosystem dynamics and engineering bioreactors. NSF CBET-1511340, NSF CAREER-1554095.

  1. Factors Motivating and Hindering Information and Communication Technologies Action Competence

    Directory of Open Access Journals (Sweden)

    Adile Aşkım Kurt

    2013-01-01

    Full Text Available Information and Communication Technologies Action Competence (ICTAC can be defined as “individuals’ motivation and capacity to voluntarily employ their ICT skills for initiating or taking part in civic actions”. Since academic staff and teachers in ICT related fields have crucial roles in training action-competent individuals, this study aimed to determine the views of preservice teachers and instructors in Computer Education and Instructional Technology (CEIT departments about the motivating and hindering factors regarding ICTAC. Researchers used purposeful sampling technique and identified seven instructors and 16 students attending outlier CEIT departments from four different Turkish state universities. Since there is no contemporary framework on factors motivating or hindering ICTAC, the study was conducted with a qualitative approach and the data were collected through semi-structured interviews. Factors motivating and hindering ICTAC were identified through a content analysis. Findings of the study are believed to guide ICT and ICT education professionals in training students with higher levels of ICTAC and guide the course developers to focus on relevant social responsibility issues

  2. Multiple hindered rotators in a gyroscope-inspired tribenzylamine hemicryptophane.

    Science.gov (United States)

    Khan, Najat S; Perez-Aguilar, Jose Manuel; Kaufmann, Tara; Hill, P Aru; Taratula, Olena; Lee, One-Sun; Carroll, Patrick J; Saven, Jeffery G; Dmochowski, Ivan J

    2011-03-04

    A gyroscope-inspired tribenzylamine hemicryptophane provides a vehicle for exploring the structure and properties of multiple p-phenylene rotators within one molecule. The hemicryptophane was synthesized in three steps in good overall yield using mild conditions. Three rotator-forming linkers were cyclized to form a rigid cyclotriveratrylene (CTV) stator framework, which was then closed with an amine. The gyroscope-like molecule was characterized by (1)H NMR and (13)C NMR spectroscopy, and the structure was solved by X-ray crystallography. The rigidity of the two-component CTV-trismethylamine stator was investigated by (1)H variable-temperature (VT) NMR experiments and molecular dynamics simulations. These techniques identified gyration of the three p-phenylene rotators on the millisecond time scale at -93 °C, with more dynamic but still hindered motion at room temperature (27 °C). The activation energy for the p-phenylene rotation was determined to be ~10 kcal mol(-1). Due to the propeller arrangement of the p-phenylenes, their rotation is hindered but not strongly correlated. The compact size, simple synthetic route, and molecular motions of this gyroscope-inspired tribenzylamine hemicryptophane make it an attractive starting point for controlling the direction and coupling of rotators within molecular systems.

  3. Factors Hindering the Integration of CALL in a Tertiary Institution

    Directory of Open Access Journals (Sweden)

    Izaham Shah Ismail

    2008-12-01

    Full Text Available The field of Computer Assisted Language Learning (CALL is a field that is constantly evolving as it is very much dependent on the advancement of computer technologies. With new technologies being invented almost every day, experts in the field are looking for ways to apply these new technologies in the language classroom. Despite that, teachers are said to be slow at adopting technology in their classrooms and language teachers, whether at schools or tertiary institutions, are no exception. This study attempts to investigate the factors that hinder ESL instructors at an institution of higher learning from integrating CALL in their lessons. Interviews were conducted with five ESL instructors and results revealed that factors which hinder them from integrating CALL in their teaching are universal factors such as knowledge in technology and pedagogy, computer facilities and resources, absence of exemplary integration of CALL, personal beliefs on language teaching, views on the role of a computers as teacher, and evaluation of learning outcomes.

  4. Teamwork in a coronary care unit: facilitating and hindering aspects.

    Science.gov (United States)

    Goulart, Bethania Ferreira; Camelo, Silvia Helena Henriques; Simões, Ana Lúcia de Assis; Chaves, Lucieli Dias Pedreschi

    2016-01-01

    To identify, within a multidisciplinary team, the facilitating and hindering aspects for teamwork in a coronary care unit. A descriptive study, with qualitative and quantitative data, was carried out in the coronary care unit of a public hospital. The study population consisted of professionals working in the unit for at least one year. Those who were on leave or who were not located were excluded. The critical incident technique was used for data collection, by means of semi-structured interviews. For data analysis, content analysis and the critical incident technique were applied. Participants were 45 professionals: 29 nursing professionals; 11 physicians; 4 physical therapists; and 1 psychologist. A total of 49 situations (77.6% with negative references); 385 behaviors (54.2% with positive references); and 182 consequences emerged (71.9% with negative references). Positive references facilitate teamwork, whereas negative references hinder it. A collaborative/communicative interprofessional relationship was evidenced as a facilitator; whereas poor collaboration among agents/inadequate management was a hindering aspect. Despite the prevalence of negative situations and consequences, the emphasis on positive behaviors reveals the efforts the agents make in order to overcome obstacles and carry out teamwork. Identificar, junto à equipe multiprofissional, aspectos facilitadores e dificultadores do trabalho em equipe em Unidade Coronariana. Estudo descritivo, com dados qualitativos e quantitativos, realizado em Unidade Coronariana/Hospital público. População constituída de profissionais atuantes na Unidade há, pelo menos, um ano. Excluídos os afastados do trabalho e os que não foram não localizados. Para a coleta de informações, utilizou-se da Técnica do Incidente Crítico por meio de entrevista semiestruturada. Para a análise dos dados, utilizaram-se da Análise de Conteúdo e Técnica do Incidente Crítico. Participaram 45 profissionais: 29

  5. How Christian Spiritual and Religious Beliefs Help and Hinder Counselors' Empathy toward Clients

    Science.gov (United States)

    Morrison, Marie; Borgen, William A.

    2010-01-01

    The critical incident technique was used to examine how counselors' religion and spirituality help and hinder counselor empathy toward clients. Twelve counselors holding Christian beliefs identified 242 helping and 25 hindering incidents that formed 14 helping and 3 hindering categories. Categories reflected counselors relying on a natural…

  6. Processing fluency hinders subsequent recollection: An electrophysiological study

    Directory of Open Access Journals (Sweden)

    Bingbing eLi

    2015-06-01

    Full Text Available Although many behavioural studies have investigated the effect of processing fluency on subsequent recognition memory, little research has examined the neural mechanism of this phenomenon. The present study aimed to explore the electrophysiological correlates of the effects of processing fluency on subsequent recognition memory by using an event-related potential (ERP approach. The masked repetition priming paradigm was used to manipulate processing fluency in the study phase, and the R/K paradigm was utilised to investigate which recognition memory process (familiarity or recollection was affected by processing fluency in the test phase. Converging behavioural and ERP results indicated that increased processing fluency impaired subsequent recollection. Results from the analysis of ERP priming effects in the study phase indicated that increased perceptual processing fluency of object features, reflected by the N/P 190 priming effect, can hinder encoding activities, reflected by the LPC priming effect, which leads to worse subsequent recollection based recognition memory. These results support the idea that processing fluency can influence subsequent recognition memory and provide a potential neural mechanism underlying this effect. However, further studies are needed to examine whether processing fluency can affect subsequent familiarity.

  7. Personal health records: is rapid adoption hindering interoperability?

    Science.gov (United States)

    Studeny, Jana; Coustasse, Alberto

    2014-01-01

    The establishment of the Meaningful Use criteria has created a critical need for robust interoperability of health records. A universal definition of a personal health record (PHR) has not been agreed upon. Standardized code sets have been built for specific entities, but integration between them has not been supported. The purpose of this research study was to explore the hindrance and promotion of interoperability standards in relationship to PHRs to describe interoperability progress in this area. The study was conducted following the basic principles of a systematic review, with 61 articles used in the study. Lagging interoperability has stemmed from slow adoption by patients, creation of disparate systems due to rapid development to meet requirements for the Meaningful Use stages, and rapid early development of PHRs prior to the mandate for integration among multiple systems. Findings of this study suggest that deadlines for implementation to capture Meaningful Use incentive payments are supporting the creation of PHR data silos, thereby hindering the goal of high-level interoperability.

  8. Is Urban Planning in Australia Hindered by Poor Metropolitan Governance?

    Directory of Open Access Journals (Sweden)

    Paul Burton

    2017-11-01

    Full Text Available There are many calls for urban planning in Australia to be reformed, although often in contradictory ways. For example, some argue it should be capable of delivering greater certainty to developers while others call for more flexibility in processes of urban development regulation; some would like to roll back its regulatory impact while others argue for a renewal of planning’s commitment to promoting social and spatial justice. The Australian planning system is also held to be hindered by a comparative lack of planning at and for the metropolitan scale. This is connected to the absence of well-developed structures of metropolitan governance in what is a three-tier federal system, with most power over planning concentrated at the State and Territory government scale. The paper explores this putative hindrance by considering three important issues in Australian urban policy debates about the efficacy of contemporary multi-level governance arrangements: spatial scale; identity and legitimacy; and efficiency and effectiveness. It includes some analysis of the case made for a more explicit and rigorous national urban policy and how this might relate to lower level planning regimes. The paper focuses on recent urban policy and planning initiatives in South East Queensland, one of Australia’s fastest growing metropolitan regions, and concludes that while incremental but nonetheless significant improvements in planning policy and practice are possible, these are unlikely to satisfy those calling for more radical changes to improve the Australian planning system.

  9. Processing fluency hinders subsequent recollection: an electrophysiological study.

    Science.gov (United States)

    Li, Bingbing; Gao, Chuanji; Wang, Wei; Guo, Chunyan

    2015-01-01

    Although many behavioral studies have investigated the effect of processing fluency on subsequent recognition memory, little research has examined the neural mechanism of this phenomenon. The present study aimed to explore the electrophysiological correlates of the effects of processing fluency on subsequent recognition memory by using an event-related potential (ERP) approach. The masked repetition priming paradigm was used to manipulate processing fluency in the study phase, and the R/K paradigm was utilized to investigate which recognition memory process (familiarity or recollection) was affected by processing fluency in the test phase. Converging behavioral and ERP results indicated that increased processing fluency impaired subsequent recollection. Results from the analysis of ERP priming effects in the study phase indicated that increased perceptual processing fluency of object features, reflected by the N/P 190 priming effect, can hinder encoding activities, reflected by the LPC priming effect, which leads to worse subsequent recollection based recognition memory. These results support the idea that processing fluency can influence subsequent recognition memory and provide a potential neural mechanism underlying this effect. However, further studies are needed to examine whether processing fluency can affect subsequent familiarity.

  10. Does hindered transport theory apply to desalination membranes?

    Science.gov (United States)

    Dražević, Emil; Košutić, Krešimir; Kolev, Vesselin; Freger, Viatcheslav

    2014-10-07

    As reverse osmosis (RO) and nanofiltration polyamide membranes become increasingly used for water purification, prediction of pollutant transport is required for membrane development and process engineering. Many popular models use hindered transport theory (HTT), which considers a spherical solute moving through an array of fluid-filled rigid cylindrical pores. Experiments and molecular dynamic simulations, however, reveal that polyamide membranes have a distinctly different structure of a "molecular sponge", a network of randomly connected voids widely distributed in size. In view of this disagreement, this study critically examined the validity of HTT by directly measuring diffusivities of several alcohols within a polyamide film of commercial RO membrane using attenuated total reflection-FTIR. It is found that measured diffusivities deviate from HTT predictions by as much as 2-3 orders of magnitude. This result indicates that HTT does not adequately describe solute transport in desalination membranes. As a more adequate alternative, the concept of random resistor networks is suggested, with resistances described by models of activated transport in "soft" polymers without a sharp size cutoff and with a proper address of solute partitioning.

  11. Isomerization and fluorescence characteristics of sterically hindered azobenzene derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Han, Mina, E-mail: mrhan@echem.titech.ac.j [Flucto-Order Functions Asian Collaboration Team, RIKEN Advanced Science Institute, RIKEN 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)] [Department of Electronic Chemistry, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502 (Japan); Ishikawa, Daisuke [Department of Electronic Chemistry, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502 (Japan); Muto, Emi [Faculty of Education and Integrated Arts and Sciences, Waseda University, 1-6-1 Nishi-Waseda, Shinjuku, Tokyo 169-8050 (Japan); Hara, Masahiko [Flucto-Order Functions Asian Collaboration Team, RIKEN Advanced Science Institute, RIKEN 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)] [Department of Electronic Chemistry, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502 (Japan)

    2009-10-15

    We report synthesis and isomerization behaviors of sterically hindered azobenzene derivatives (1 and 2) with decyloxy and hydroxy groups, respectively, and their fluorescence enhancement under UV light irradiation characterized by means of absorption and fluorescence spectroscopy measurements. Upon irradiation of as-prepared solution (1) with UV light (approx200 mJ/cm{sup 2}) a cis-rich photostationary state was reached. Obviously different from 2 showing very fast thermal cis-to-trans isomerization within 2 min, slow cis-to-trans thermal back isomerization of 1 with a long alkyl chain at ambient temperature was observed on the time scale of weeks. In contrast to no striking changes in absorption and fluorescence spectra of compound 2, the azobenzene 1 showed green fluorescence upon prolonged irradiation with UV light (about 3-8 J/cm{sup 2} exposure doses), although both the initial trans-rich and cis-rich states of azobenzene molecules were not fluorescent in solution. The stability of fluorescence efficiency caused by drying and redissolving processes was examined.

  12. Personal Health Records: Is Rapid Adoption Hindering Interoperability?

    Science.gov (United States)

    Studeny, Jana; Coustasse, Alberto

    2014-01-01

    The establishment of the Meaningful Use criteria has created a critical need for robust interoperability of health records. A universal definition of a personal health record (PHR) has not been agreed upon. Standardized code sets have been built for specific entities, but integration between them has not been supported. The purpose of this research study was to explore the hindrance and promotion of interoperability standards in relationship to PHRs to describe interoperability progress in this area. The study was conducted following the basic principles of a systematic review, with 61 articles used in the study. Lagging interoperability has stemmed from slow adoption by patients, creation of disparate systems due to rapid development to meet requirements for the Meaningful Use stages, and rapid early development of PHRs prior to the mandate for integration among multiple systems. Findings of this study suggest that deadlines for implementation to capture Meaningful Use incentive payments are supporting the creation of PHR data silos, thereby hindering the goal of high-level interoperability. PMID:25214822

  13. SNARE zippering is hindered by polyphenols in the neuron

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yoosoo [Department of Genetic Engineering and Center for Human Interface Nanotechnology, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Biomedical Research Institute, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Kim, Se-Hyun; Heo, Paul; Kong, Byoungjae; Shin, Jonghyeok; Jung, Young-Hun; Yoon, Keejung; Chung, Woo-Jae [Department of Genetic Engineering and Center for Human Interface Nanotechnology, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Shin, Yeon-Kyun [Biomedical Research Institute, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, IA 50011 (United States); Kweon, Dae-Hyuk, E-mail: dhkweon@skku.edu [Department of Genetic Engineering and Center for Human Interface Nanotechnology, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

    2014-07-18

    Highlights: • Membrane fusion driven by SNARE complex is hindered by several polyphenols. • Distinctive inhibitory effect of each polyphenol on SNARE zippering in neuron was examined. • FRET between fluorescence protein-tagged SNAREs probed well SNARE zippering in PC12 cells. • Delphinidin and cyanidin inhibit N-terminal SNARE nucleation in Ca{sup 2+}-independent manner. • Myricetin inhibits Ca{sup 2+}-dependent transmembrane association of SNARE complex. - Abstract: Fusion of synaptic vesicles with the presynaptic plasma membrane in the neuron is mediated by soluble N-ethylmaleimide-sensitive fusion protein-attachment protein receptor (SNARE) proteins. SNARE complex formation is a zippering-like process which initiates at the N-terminus and proceeds to the C-terminal membrane-proximal region. Previously, we showed that this zippering-like process is regulated by several polyphenols, leading to the arrest of membrane fusion and the inhibition of neuroexocytosis. In vitro studies using purified SNARE proteins reconstituted in liposomes revealed that each polyphenol uniquely regulates SNARE zippering. However, the unique regulatory effect of each polyphenol in cells has not yet been examined. In the present study, we observed SNARE zippering in neuronal PC12 cells by measuring the fluorescence resonance energy transfer (FRET) changes of a cyan fluorescence protein (CFP) and a yellow fluorescence protein (YFP) fused to the N-termini or C-termini of SNARE proteins. We show that delphinidin and cyanidin inhibit the initial N-terminal nucleation of SNARE complex formation in a Ca{sup 2+}-independent manner, while myricetin inhibits Ca{sup 2+}-dependent transmembrane domain association of the SNARE complex in the cell. This result explains how polyphenols exhibit botulinum neurotoxin-like activity in vivo.

  14. Hindered erosion: The biological mediation of noncohesive sediment behavior

    Science.gov (United States)

    Chen, X. D.; Zhang, C. K.; Paterson, D. M.; Thompson, C. E. L.; Townend, I. H.; Gong, Z.; Zhou, Z.; Feng, Q.

    2017-06-01

    Extracellular polymeric substances (EPS) are ubiquitous on tidal flats but their impact on sediment erosion has not been fully understood. Laboratory-controlled sediment beds were incubated with Bacillus subtilis for 5, 10, 16, and 22 days before the erosion experiments, to study the temporal and spatial variations in sediment stability caused by the bacterial secreted EPS. We found the biosedimentary systems showed different erosional behavior related to biofilm maturity and EPS distribution. In the first stage (5 days), the biosedimentary bed was more easily eroded than the clean sediment. With increasing growth period, bound EPS became more widely distributed over the vertical profile resulting in bed stabilization. After 22 days, the bound EPS was highly concentrated within a surface biofilm, but a relatively high content also extended to a depth of 5 mm and then decayed sharply with depth. The biofilm increased the critical shear stress of the bed and furthermore, it enabled the bed to withstand threshold conditions for an increased period of time as the biofilm degraded before eroding. After the loss of biofilm protection, the high EPS content in the sublayers continued to stabilize the sediment (hindered erosion) by binding individual grains, as visualized by electron microscopy. Consequently, the bed strength did not immediately revert to the abiotic condition but progressively adjusted, reflecting the depth profile of the EPS. Our experiments highlight the need to treat the EPS-sediment conditioning as a bed-age associated and depth-dependent variable that should be included in the next generation of sediment transport models.

  15. Social-ecological traps hinder rural development in southwestern Madagascar

    Directory of Open Access Journals (Sweden)

    Hendrik Hänke

    2017-03-01

    Full Text Available The semiarid Mahafaly region in southwestern Madagascar is not only a unique biodiversity hotspot, but also one of the poorest regions in the world. Crop failures occur frequently, and despite a great number of rural development programs, no effective progress in terms of improved yields, agricultural income, or well-being among farming households has been observed. In addition to the severe development challenges in the region, environmental degradation and the loss of biodiversity are prevailing issues. This paper takes a social-ecological systems perspective to analyze why the region appears locked in poverty. Specifically, we address the social-ecological interaction between environmental factors such as low and variable precipitation, the lack of sustainable intensification in agriculture resulting in recalcitrant hunger, and several environmental degradation trends. The study is based on (i longitudinal data from 150 farming households interviewed at high temporal resolution during the course of 2014, and (ii extensive recall surveys from the southwestern Madagascar project region. The analysis reveals a complex interplay of pronounced seasonality in income generation due to recurrent droughts and crop failures making local farmers highly risk averse. This interplay results in a gradual depletion of environmental assets and hinders the accumulation of capital in the hands of smallholder farmers, and improvements in agricultural production even where environmental conditions would allow for it. As a result, households are insufficiently buffered and insured against repetitive income and food security shocks. This can be understood as a set of interacting, partly nested social-ecological traps, which entrench the Mahafalian smallholder population in deep poverty while the productivity of the environment declines. We provide new insights on the interplay between hunger, poverty, and loss of environmental assets in a global biodiversity

  16. Snowmelt onset hinders bromine monoxide heterogeneous recycling in the Arctic

    Science.gov (United States)

    Burd, Justine A.; Peterson, Peter K.; Nghiem, Son V.; Perovich, Don K.; Simpson, William R.

    2017-08-01

    Reactive bromine radicals (bromine atoms, Br, and bromine monoxide, BrO) deplete ozone and alter tropospheric oxidation chemistry during the Arctic springtime (February-June). As spring transitions to summer (May-June) and snow begins to melt, reactive bromine events cease and BrO becomes low in summer. In this study, we explore the relationship between the end of the reactive bromine season and snowmelt timing. BrO was measured by Multi-AXis Differential Optical Absorption Spectrometer at Utqiaġvik (Barrow), AK, from 2012 to 2016 and on drifting buoys deployed in Arctic sea ice from 2011 to 2016, a total of 13 site and year combinations. The BrO seasonal end date (SED) was objectively determined and was compared to surface-air-temperature-derived melt onset date (MOD). The SED was highly correlated with the MOD (N = 13, R2 = 0.983, RMS = 1.9 days), and BrO is only observed at subfreezing temperatures. In subsets of these sites and years where ancillary data were available, we observed that snowpack depth reduced and rain precipitation occurred within a few days of the SED. These data are consistent with snowpack melting hindering BrO recycling, which is necessary to maintain enhanced BrO concentrations. With a projected warmer Arctic, a shift to earlier snowmelt seasons could alter the timing and role of halogen chemical reactions in the Arctic with impacts on ozone depletion and mercury deposition.Plain Language SummaryReactive bromine events in the Arctic are common in spring and deplete ozone and cause mercury deposition. These events are affected by snow and ice, which are changing in the Arctic; therefore, we need to understand how environmental conditions affect reactive bromine chemistry. We find that the reactive bromine season ends when snowpack begins to melt. Through these full seasonal observations, we find that reactive bromine events occur to warmer temperatures than previously reported, with 0°C being the observed threshold above which reactive

  17. Hindered settling and the formation of layered intrusions

    Science.gov (United States)

    Bons, Paul D.; Baur, Albrecht; Elburg, Marlina A.; Lindhuber, Matthias J.; Marks, Michael A. W.; Soesoo, Alvar; van Milligen, Boudewijn P.; Walte, Nicolas P.

    2015-04-01

    Layered intrusions are characterized by (often repetitive) layering on a range of scales. Many explanations for the formation of such layering have been proposed over the past decades. We investigated the formation of "mats" by hindered crystal settling, a model that was first suggested by Lauder (1964). The interaction of sinking and rising crystals leads to the amplification of perturbations in crystal density within a magma chamber, a process similar to the formation of traffic jams in dense traffic (Bons et al., 2015). Once these "crystal traffic jams" form they constitute a barrier for further settling of crystals. Between these barriers, the magma evolves in a semi-closed system in which stratification may develop by gravitational sorting. Barriers, and therefore layers, form sequentially during inward cooling of the magma chamber. Barring later equilibration, mineralogical and geochemical trends within the layers are repetitive, but with variations due to the random process of initial perturbation formation. Layers can form in the transition between two end-member regimes: (1) in a fast cooling and/or viscous magma crystals cannot sink or float a significant distance and minerals are distributed homogeneously throughout the chamber; (2) in a slow cooling and/or low-viscosity magma crystals can quickly settle at the top and bottom of the chamber and crystals concentrations are never high enough to form "traffic jams". As a result, heavy and light minerals get fully separated in the chamber. Between these two end members, crystals can sink and float a significant distance, but not the whole height of the magma chamber before entrapment in "traffic jams". We illustrate the development of layers with numerical models and compare the results with the layered nepheline syenites (kakortokites) of the Ilímaussaq intrusion in SW Greenland. References: Bons, P.D., Baur, A., Elburg, M.A., Lindhuber, M.J., Marks, M.A.W., Soesoo, A., van Milligen, B.P., Walte, N.P. 2015

  18. Relationship structure-antioxidant activity of hindered phenolic compounds

    Directory of Open Access Journals (Sweden)

    Weng, X. C.

    2014-12-01

    Full Text Available The relationship between the structure and the antioxidant activity of 21 hindered phenolic compounds was investigated by Rancimat and DPPH· tests. 3-tert-butyl-5-methylbenzene-1,2-diol is the strongest antioxidant in the Rancimat test but not in the DPPH· test because its two hydroxyl groups have very strong steric synergy. 2,6-Ditert-butyl-4-hydroxy-methylphenol exhibits a strong antioxidant activity as 2,6-ditertbutyl- 4-methoxyphenol does in lard. 2,6-Ditert-butyl-4- hydroxy-methylphenol also exhibits stronger activity than 2-tert-butyl-4- methoxyphenol. The methylene of 2,6-ditert-butyl-4-hydroxy-methylphenol can provide a hydrogen atom to active free radicals like a phenolic hydroxyl group does because it is greatly activated by both the aromatic ring and hydroxyl group. Five factors affect the antioxidant activities of the phenolic compounds: how stable the phenolic compound free radicals are after providing hydrogen atoms; how many hy drogen atoms each of the phenolic compounds can provide; how fast the phenolic compounds provide hydrogen atoms; how easily the phenolic compound free radicals can combine with more active free radicals, and whether or not a new antioxidant can form after the phenolic compound provides hydrogen atoms.La relación entre estructura y la actividad antioxidante de 21 compuestos fenólicos con impedimentos estéricos fue investigado mediante ensayos con Rancimat y DPPH·. El 3-terc-butil-5-metilbenceno-1,2-diol es el antioxidante más potente en los ensayos mediante Rancimat pero no mediante ensayos con DPPH·, porque sus dos grupos hidroxilo tienen una fuerte sinergia estérica. El 2,6-Di-terc-butil-4-hidroxi-metil-fenol mostró una actividad antioxidante tan fuerte como el 2,6-di-ter-butil-4-metoxifenol en ensayos con manteca de cerdo. El 2,6-di-terc-butil-4-hidroxi-metilfenol también mostró una actividad más fuerte que el 2-terc-butil-4-metoxifenol. El grupo metileno del 2,6-di-ter-butil-4-hidroxi

  19. Preparation of metallic cation conducting polymers based on sterically hindered phenols containing polymeric systems

    Science.gov (United States)

    Skotheim, T.A.; Okamoto, Yoshiyuki; Lee, H.S.

    1989-11-21

    The present invention relates to ion-conducting solvent-free polymeric systems characterized as being cationic single ion conductors. The solvent-free polymer electrolytes comprise a flexible polymer backbone to which is attached a metal salt, such as a lithium, sodium or potassium salt, of a sterically hindered phenol. The solid polymer electrolyte may be prepared either by (1) attaching the hindered phenol directly to a flexible polymeric backbone, followed by neutralization of the phenolic OH's or (2) reacting the hindered phenol with a polymer precursor which is then polymerized to form a flexible polymer having phenolic OH's which are subsequently neutralized. Preferably the hindered phenol-modified polymeric backbone contains a polyether segment. The ionic conductivity of these solvent-free polymer electrolytes has been measured to be in the range of 10[sup [minus]4] to 10[sup [minus]7] S cm[sup [minus]1] at room temperature.

  20. Preparation of metallic cation conducting polymers based on sterically hindered phenols containing polymeric systems

    Energy Technology Data Exchange (ETDEWEB)

    Skotheim, T.A.; Okamoto, Yoshiyuki; Lee, H.S.

    1989-11-21

    The present invention relates to ion-conducting solvent-free polymeric systems characterized as being cationic single ion conductors. The solvent-free polymer electrolytes comprise a flexible polymer backbone to which is attached a metal salt, such as a lithium, sodium or potassium salt, of a sterically hindered phenol. The solid polymer electrolyte may be prepared either by (1) attaching the hindered phenol directly to a flexible polymeric backbone, followed by neutralization of the phenolic OH's or (2) reacting the hindered phenol with a polymer precursor which is then polymerized to form a flexible polymer having phenolic OH's which are subsequently neutralized. Preferably the hindered phenol-modified polymeric backbone contains a polyether segment. The ionic conductivity of these solvent-free polymer electrolytes has been measured to be in the range of 10[sup [minus]4] to 10[sup [minus]7] S cm[sup [minus]1] at room temperature.

  1. A protocol for amide bond formation with electron deficient amines and sterically hindered substrates

    DEFF Research Database (Denmark)

    Due-Hansen, Maria E; Pandey, Sunil K; Christiansen, Elisabeth

    2016-01-01

    A protocol for amide coupling by in situ formation of acyl fluorides and reaction with amines at elevated temperature has been developed and found to be efficient for coupling of sterically hindered substrates and electron deficient amines where standard methods failed.......A protocol for amide coupling by in situ formation of acyl fluorides and reaction with amines at elevated temperature has been developed and found to be efficient for coupling of sterically hindered substrates and electron deficient amines where standard methods failed....

  2. U(SMes*)n, (n = 3, 4) and Ln(SMes*)3 (Ln = La, Ce, Pr, Nd): lanthanide(III)/actinide(III) differentiation in agostic interactions and an unprecedented eta3 ligation mode of the arylthiolate ligand, from X-ray diffraction and DFT analysis.

    Science.gov (United States)

    Roger, Mathieu; Barros, Noémi; Arliguie, Thérèse; Thuéry, Pierre; Maron, Laurent; Ephritikhine, Michel

    2006-07-12

    Reaction of U(NEt(2))(4) with HS-2,4,6-(t)Bu(3)C(6)H(2) (HSMes) gave U(SMes)(3)(NEt(2))(py) (1), whereas similar treatment of U[N(SiMe(3))SiMe(2)CH(2)][N(SiMe(3))(2)](2) afforded U(SMes)[N(SiMe(3))(2)](3) (2) and U(SMes)(3)[N(SiMe(3))(2)]. The first neutral homoleptic uranium(IV) thiolate to have been crystallographically characterized, U(SMes)(4) (4), was isolated from the reaction of U(BH(4))(4) and KSMes. The first homoleptic thiolate complex of uranium(III), U(SMes)(3) (5), was synthesized by protonolysis of U[N(SiMe(3))(2)](3) with HSMes in cyclohexane. The crystal structure of 5 exhibits the novel eta(3) ligation mode for the arylthiolate ligand. Comparison of the crystal structure of 5 with those of the isomorphous lanthanide congeners Ln(SMes)(3) (Ln = La, Ce, Pr, and Nd) indicates that the U-S, U-C(ipso)(), and U-C(ortho)() bond lengths are shorter than the corresponding ones in the 4f-element analogues, when taking into account the variation in the ionic radii of the metals. The distance between the uranium and the carbon atoms involved in the U...H-C epsilon agostic interaction of each thiolate ligand is shorter, by approximately 0.05 A, than that expected from a purely ionic bonding model. The lanthanide(III)/actinide(III) differentiation was analyzed by density functional theory (DFT). The nature of the M-S bond is shown to be ionic strongly polarized at the sulfur for M = U and iono-covalent (i.e. strongly ionic with low orbital interaction), for M = Ln. The strength of the U...H-C epsilon agostic interaction is proposed to be controlled by the maximization of the interaction between U(+) and S(-) under steric constraints. The eta(3) ligation mode of the arylthiolate ligand is also obtained from DFT.

  3. Thermal Behaviour of Some Azo Dyes Containing Sterically Hindered and Water-Soluble Groups

    OpenAIRE

    KOCAOKUTGEN, Hasan; HEREN, Zerrin

    1998-01-01

    Thermal behaviour of six azo dyes containing steric hindered groups such as tert-butyl, sec-butyl and isopropyl, were investigated by means of thermogravimetry (TG), differential thermal analysis (DTA) and differential thermogravimetry (DTG). The thermal decomposition points and amount of volatile pyrolysis products, were determined in nitrogen atmosphere using TG, DTA and DTG curves.

  4. On the hindered settling of suspensions of mud and mud-sand mixtures

    NARCIS (Netherlands)

    Dankers, P.J.T.

    2006-01-01

    Highly concentrated suspensions are present in many natural environments. When the concentration becomes large enough, particles start to interfere with each other and their settling velocity reduces. This is called hindered settling. As a result of the reduced settling velocity, particles remain in

  5. Educated Immigrant Women Workers Doing Well with Change: Helping and Hindering Factors

    Science.gov (United States)

    Koert, Emily; Borgen, William A.; Amundson, Norman E.

    2011-01-01

    The authors investigated the strategies that helped or hindered 10 immigrant women workers to do well with change that affected their work. A total of 182 incidents were extracted and grouped into 9 categories: personal beliefs/traits/values, taking action, skills/education, personal challenges, self-care, relationships/support,…

  6. The synthesis of sterically hindered amines by a direct reductive amination of ketones.

    Science.gov (United States)

    Yagafarov, Niyaz Z; Kolesnikov, Pavel N; Usanov, Dmitry L; Novikov, Valentin V; Nelyubina, Yulia V; Chusov, Denis

    2016-01-25

    An atom-economical methodology for the synthesis of sterically hindered tertiary amines was developed, which is based on complementary Rh- and Ru-catalyzed direct reductive amination of ketones with primary and secondary amines using carbon monoxide as a deoxygenating agent.

  7. Helpful and Hindering Multicultural Events in Group Supervision: Climate and Multicultural Competence

    Science.gov (United States)

    Kaduvettoor, Anju; O'Shaughnessy, Tiffany; Mori, Yoko; Beverly, Clyde, III; Weatherford, Ryan D.; Ladany, Nicholas

    2009-01-01

    This study examines the relationship between multicultural events in group supervision, group climate, and supervisee multicultural competence using a mixed qualitative/quantitative design. The discovery-oriented approach yielded 196 helpful and hindering multicultural events among 136 participants. The most common events included multicultural…

  8. Issues promoting and hindering girls' well-being in Northern Finland.

    Science.gov (United States)

    Wiens, Varpu; Kyngäs, Helvi; Pölkki, Tarja

    2017-08-01

    Well-being is a complex concept that includes elements of inequality due to socio-economics, living environment or gender. Every person also encounters unique situations and has different experiences of well-being. This qualitative study aims to describe what issues promote and hinder the well-being of girls aged 13-16 in Northern Finland. A total of 117 girls aged 13-16 living in Northern Finland were asked to write about the issues that hinder and promote their well-being. The girls' responses were analysed using content analysis. After analysis, two combining categories were discovered: issues hindering well-being were a debilitating sphere of life and negative experiences in life, and issues promoting well-being were positive subjective sensations and favourably perceived conditions. The results of this study indicate that girls' well-being is connected to their social and physical environment. As the girls' view of the issues that promote or hinder health are connected and interact with their living environment, there is also a need for health promotion measures to take into account both the individuals and the environment in which they function and live. This view challenges us to see health promotion in a broader way-a way which takes into account structural and political factors, individual consultation and empowerment. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  9. Grafting of Hindered Phenol Groups onto Ethylene/α-Olefin Copolymer by Nitroxide Radical Coupling

    Directory of Open Access Journals (Sweden)

    Serena Coiai

    2017-12-01

    Full Text Available The covalent immobilization of hindered phenol groups, with potential antioxidant activity, onto an ethylene/α-olefin (EOC copolymer was carried out by the nitroxide radical coupling (NRC reaction performed in the melt with a peroxide and the 3,5-di-tert-butyl-4-hydroxybenzoyl-2,2,6,6-tetramethylpiperidine-1-oxyl radical (BHB-T. Functionalized EOC (EOC-g-(BHB-T was exposed to photo- and thermo-oxidation. By comparison with some model compounds bearing the (2,2,6,6-tetramethylpiperidin-1-yloxyl (TEMPO moiety or the hindered phenol unit, it was observed that the grafted BHB-T could effectively help the stabilization of the polymer matrix both under photo- and thermo-oxidation. In addition, the immobilization of BHB-T can effectively increase the service life of the functionalized polymers when polymer films were put in contact with ethanol solution thus simulating a possible application of the modified polymer.

  10. Limitations to teaching children 2 + 2 = 4: typical arithmetic problems can hinder learning of mathematical equivalence.

    Science.gov (United States)

    McNeil, Nicole M

    2008-01-01

    Do typical arithmetic problems hinder learning of mathematical equivalence? Second and third graders (7-9 years old; N= 80) received lessons on mathematical equivalence either with or without typical arithmetic problems (e.g., 15 + 13 = 28 vs. 28 = 28, respectively). Children then solved math equivalence problems (e.g., 3 + 9 + 5 = 6 + _), switched lesson conditions, and solved math equivalence problems again. Correct solutions were less common following instruction with typical arithmetic problems. In a supplemental experiment, fifth graders (10-11 years old; N= 19) gave fewer correct solutions after a brief intervention on mathematical equivalence that included typical arithmetic problems. Results suggest that learning is hindered when lessons activate inappropriate existing knowledge.

  11. Statin Use and Self-Reported Hindering Muscle Complaints in Older Persons: A Population Based Study.

    Directory of Open Access Journals (Sweden)

    Milly A van der Ploeg

    Full Text Available Statins are widely used by older persons in primary and secondary prevention of cardiovascular disease. Although serious adverse events are rare, many statin users report mild muscle pain and/or muscle weakness. It's unclear what impact statins exert on a patient's daily life. Research on statin related side effects in older persons is relatively scarce. We therefore investigated the relation between statin use and self-reported hindering muscle complaints in older persons in the general population.The present research was performed within the Integrated Systematic Care for Older Persons (ISCOPE study in the Netherlands (Netherlands trial register, NTR1946. All registered adults aged ≥ 75 years from 59 participating practices (n = 12,066 were targeted. Information about the medical history and statin use at baseline and after 9 months was available for 4355 participants from the Electronic Patient Records of the general practitioners. In the screening questionnaire at baseline we asked participants: 'At the moment, which health complaints limit you the most in your day-to-day life?' Answers indicating muscle or musculoskeletal complaints were coded as such. No specific questions about muscle complaints were asked.The participants had a median age of 80.3 (IQR 77.6-84.4 years, 60.8% were female and 28.5% had a history of CVD. At baseline 29% used a statin. At follow-up, no difference was found in the prevalence of self-reported hindering muscle complaints in statin users compared to non-statin users (3.3% vs. 2.5%, OR 1.39, 95% CI 0.94-2.05; P = 0.98. Discontinuation of statin use during follow-up was independent of self-reported hindering muscle complaints.Based on the present findings, prevalent statin use in this community-dwelling older population is not associated with self-reported hindering muscle complaints; however, the results might be different for incident users.

  12. Helpful and Hindering Factors in Psychodrama Field Training: A Longitudinal Mixed Methods Study of Student Development

    Directory of Open Access Journals (Sweden)

    Bracha Azoulay

    2018-02-01

    Full Text Available Although the literature indicates that students in mental health professions start to form their professional identity and competence in graduate school, there are few studies on the in-training experience of creative arts therapies students. This mixed methods study examined how five first-year students in a psychodrama master’s degree program in Israel experienced their field training, with the aim of identifying the factors likely to promote or hinder the development of their professional identity and sense of professional ability. Longitudinal data were collected weekly throughout the 20-week field training experience. The students reported qualitatively on helpful and hindering factors and were assessed quantitatively on questionnaires measuring professional identity, perceived demands-abilities fit, client involvement, and therapy session evaluations. A thematic analysis of the students’ reports indicated that a clear and defined setting and structure, observing the instructor as a role model, actively leading parts of the session, and observing fellow students were all helpful factors. The hindering factors included role confusion, issues related to coping with client resistance and disciplinary problems, as well as school end-of-year activities that disrupted the continuity of therapy. The quantitative results indicated that students’ professional identity did not significantly change over the year, whereas a U-shaped curve trajectory characterized the changes in demands-abilities fit and other measures. Students began their field training with an overstated sense of ability that soon declined and later increased. These findings provide indications of which helping and hindering factors should be maximized and minimized, to enhance students’ field training.

  13. A Facile One-Pot Process for the Formation of Hindered Tertiary Amines

    Directory of Open Access Journals (Sweden)

    Jian Sun

    2012-05-01

    Full Text Available A simple and convenient method was developed for the preparation of hindered tertiary amines via direct reductive amination of ketones with secondary aryl amines, using trichlorosilane as reducing agent and tetramethylethylenediamine (TMEDA as organic Lewis base activator. A broad range of ketones were reacted with N-methylaniline to afford the corresponding tertiary amine products in high yield. An open transition model was proposed for the reductive step.

  14. Data versus Spock: lay theories about whether emotion helps or hinders.

    OpenAIRE

    Karnaze, MM; Levine, LJ

    2017-01-01

    The android Data from Star Trek admired human emotion whereas Spock viewed emotion as irrational and maladaptive. The theory that emotions fulfil adaptive functions is widely accepted in academic psychology but little is known about laypeople's theories. The present study assessed the extent to which laypeople share Data's view of emotion as helpful or Spock's view of emotion as a hindrance. We also assessed how help and hinder theory endorsement were related to reasoning, emotion regulation,...

  15. Risk factors for prostate cancer, and motivational and hindering aspects in conducting preventive practices.

    Science.gov (United States)

    Gontijo Gomes, Cássia Regina; Resende Izidoro, Lívia Cristina; Ferreira da Mata, Luciana Regina

    2015-12-01

    Identify risk factors for Prostate Cancer (PC), preventive practices, and hindering and motivating factors for disease prevention among workers of a public university. A descriptive study, conducted with 92 workers who answered a self-administered questionnaire on the variables related to sociodemographic characteristics and clinical risk factors, sources of information about PC, practices related to prevention, and information on the hindering and motivating factors for prevention of the disease. Most (95.0%) participants had one or more risk factors for PC; 68.5% underwent completion of the prostate-specific antigen (PSA) test annually at the request of the university; 50.0% of participants never performed the digital rectal examination (DRE); the main source of information was the media (64.1%); the main complicating factor for realization of the yearly preventive screening test was the lack of request for examination by their doctor; and the main motivating reason was recognition of the severity of the disease. Most participants had risk factors for the disease, do not perform the DRE, presented difficulties in carrying out prevention, and revealed they do not receive information about the disease from healthcare professionals, which could in turn lead to an erroneous understanding, resulting in hindering factors for practices to prevent PC. Thus, health care managers and multidisciplinary teams should engage in preventive health care for men in order to initiate preventive practices, and clarify any doubts about the disease.

  16. What hinders implementation of the WHO FCTC Article 5.3? - The case of South Korea.

    Science.gov (United States)

    Lee, Sungkyu

    2016-10-01

    The aims of this study are to identify what hinders implementation of the WHO Framework Convention on Tobacco Control (FCTC) Article 5.3 in Korea, and to provide suggestions for the implementation of Article 5.3. Official governmental documents on tobacco control were reviewed. We also searched news articles for data triangulation. There were three factors that hindered the implementation of Article 5.3 in Korea. Firstly, there has been legal conflict between two tobacco-related laws, one of which is designed to promote the tobacco industry. The other is designed to promote public health. Secondly, the government has had economic interests in the tobacco industry, and its lack of action to effectively regulate the tobacco industry's corporate social responsibility (CSR) practices has hindered the implementation of Article 5.3. Thirdly, the tobacco industry's lobby and active interference in the policy-making process has been a barrier. To fully implement Article 5.3, this study suggests: defusing legal conflict between tobacco-related laws; not considering tobacco industry as a stakeholder; regulating tobacco industry's CSR activities; raising awareness of tobacco industry interference; securing transparency between the government and tobacco industry; and establishing a core group or a committee under the government to implement Article 5.3.

  17. Synthesis of Hindered Anilines: Three-Component Coupling of Arylboronic Acids, tert-Butyl Nitrite, and Alkyl Bromides.

    OpenAIRE

    Fisher, DJ; Shaum, JB; Mills, CL; Read de Alaniz, J

    2016-01-01

    The synthesis of sterically hindered amines has been a significant challenge in organic chemistry. Herein, we report a modular, three-component coupling that constructs two carbon-nitrogen bonds including a sterically hindered Csp(3)-N bond using commercially available materials. This process uses an earth-abundant copper catalyst and mild reaction conditions, allowing access to a variety of complex aromatic amines.

  18. Facilitating and Hindering Factors in Family Care Giving Process on Iranian Frail Elderly: Female Caregivers Experiences

    Directory of Open Access Journals (Sweden)

    Farahnaz Mohamadi

    2008-01-01

    Full Text Available Objectives: There is worldwide growth in the elderly population. Family care of elderly is key to long term care system and main duty of women at home. Qualitative study about facilitating and hindering factor of family care giving process provide clarified viewpoint on female caregivers need to plan and make effective supportive health policy. Methods & Materials: The present study was conducted by grounded theory. A purposive sample of 12 family caregiver participated in this study and data was gathered by deeply semi-structured interview and observation in the field. All of them were transcribed word by word and were analyzed through open, axial and selective coding according to Strauss and Corbin's approach (1998. Triangulation of the data gathering from different methods, prolonged engagement with caregivers, member check by participants and experts, was used to increase rigor of the study. Results: Female caregivers experience facilitator and hindering factors that affect the care giving process. These factors were categorized in 3 main classes of personal, familial and external factors and 9 subcategories of caregiver's knowledge on elderly care, personal characters of caregiver and care recipient, care giving burden, background of interpersonal relationship between caregiver and care recipient, familial supportive network, family member participation, formal supportive system, context of family care giving at home, and community based health care systems for elder people. Conclusion: Naturally, intervening factors in care giving process can confront caregivers with relief or difficulty Based on caregivers experiences, modifying facilitator and hindering factors by more family participation, psychosocial support, care giving education, improvement of care giving context and establishing appropriate age friendly health care systems would be effective in managing of the process by female caregivers, and could be helpful for them to be

  19. AFAP-1L1-mediated actin filaments crosslinks hinder Trypanosoma cruzi cell invasion and intracellular multiplication.

    Science.gov (United States)

    de Araújo, Karine Canuto Loureiro; Teixeira, Thaise Lara; Machado, Fabrício Castro; da Silva, Aline Alves; Quintal, Amanda Pifano Neto; da Silva, Claudio Vieira

    2016-10-01

    Host actin cytoskeleton polymerization has been shown to play an important role during Trypanosoma cruzi internalization into mammalian cell. The structure and dynamics of the actin cytoskeleton in cells are regulated by a vast number of actin-binding proteins. Here we aimed to verify the impact of AFAP-1L1, during invasion and multiplication of T. cruzi. Knocking-down AFAP-1L1 increased parasite cell invasion and intracellular multiplication. Thus, we have shown that the integrity of the machinery formed by AFAP-1L1 in actin cytoskeleton polymerization is important to hinder parasite infection. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. [Cultural dimensions of dengue that help or hinder its prevention in Mexico].

    Science.gov (United States)

    Torres López, Teresa M; Guerrero Cordero, Joana Lizeth; Salazar Estrada, José Guadalupe

    2012-03-01

    To describe the cultural dimensions that might help or hinder dengue prevention in two Mexican localities having different experiences related to this disease. A cognitive-cultural anthropological study was conducted involving the participation of 160 adults selected through purposeful sampling. The techniques of free lists and pile-sorting were used for investigating terms associated with the concept "dengue." A consensus analysis was carried out by the factoring of principal components, hierarchical cluster analysis, and multidimensional scaling. Greater consensus was observed among participants from the population having more historical experience with dengue-Santiago Ixcuintla, Nayarit-as well as more structured cultural and complex dimensions than in Guadalajara. In the latter case, participants showed a more fragmented conception of dengue, with insufficient information on its symptoms, mechanisms of transmission, and vector reservoirs. Three cultural dimensions were identified as hindering dengue prevention: confusing and insufficient information, placing responsibility for prevention on other people or on public agencies, and excessive confidence in fumigation as a preventive measure. These obstacles will need to be taken into account in the design and implementation of future prevention campaigns, disseminating information that explains the risks of fumigation and the importance of citizens and authorities jointly participating in the search for a comprehensive and sustainable solution to the dengue problem.

  1. A firoma hindering the neck bending mechanism in a tortoise (class Reptilia, subclass Anapsida, order Testudines (Chelonia

    Directory of Open Access Journals (Sweden)

    Mohamed Mostafa Shokry

    2016-03-01

    Full Text Available A 7-year old tortoise was examined for the presence of a hard swelling, hindering the necessary neck bending mechanism. Surgical removal was the solution to regain the mechanism normality.

  2. Synthesis of Hindered Anilines: Three-Component Coupling of Arylboronic Acids, tert-Butyl Nitrite, and Alkyl Bromides.

    Science.gov (United States)

    Fisher, David J; Shaum, James B; Mills, C Landon; Read de Alaniz, Javier

    2016-10-07

    The synthesis of sterically hindered amines has been a significant challenge in organic chemistry. Herein, we report a modular, three-component coupling that constructs two carbon-nitrogen bonds including a sterically hindered C sp 3 -N bond using commercially available materials. This process uses an earth-abundant copper catalyst and mild reaction conditions, allowing access to a variety of complex aromatic amines.

  3. What Hinders the Implementation of the Supply Chain Risk Management Process Into Practice Organizations?

    DEFF Research Database (Denmark)

    Gredal, Pauline; Panyi, Zsófia; Kinra, Aseem

    2017-01-01

    Supply chain risk management process (SCRMP) is being advanced as a systematic and structured approach for identifying, assessing, mitigating, and monitoring all risks arising from complex supply chains. However, while the literature deems it necessary to implement such a process as the solution...... to the increasing vulnerability companies face, there is a lack of empirical evidence on whether the process model can be implemented. This paper shows possible hindrances in the implementation of SCRMP for companies with global supply chains based on the findings of an in-depth case study. Our empirical findings...... indicate that the unavailability of information and lack of proper data management hinders the implementation of SCRMP in the context global supply chains....

  4. Molecular Simulation of Solubility and Diffusion of Hindered-Amine Light Stabilizers (HALS) in Polyethylene

    Science.gov (United States)

    Nath, Shyamal K.; de Pablo, Juan J.; Debellis, Anthony

    1997-03-01

    Hindered-amine light stabilizers (HALS) are some of the most common additives employed for prevention of photooxidation in polymers. One of the major problems encountered in polymer stabilization is that of physical loss of the additives. Such loss limits the life of the polymer and, more importantly, it can have serious consequences when the polymer is to be used for food packaging and other toxicity-sensitive applications. The loss of additives is related to their solubility and diffusion coefficient in polymers. In this work, a novel Monte Carlo formalism is proposed to determine the solubility of commercially available HALS (Tinuvin 770) in polyethylene. Diffusion coefficients is also determined by conventional molecular dynamics simulations. We report results for the solubility and diffusion of HALS in polyethylene as a function of temperature, pressure and density. We also examine the effects of branching on these quantities, and we use our findings to propose HALS structures with attractive compatibility and diffusive characteristics.

  5. Analytic energy-level densities of separable harmonic oscillators including approximate hindered rotor corrections

    Directory of Open Access Journals (Sweden)

    M. Döntgen

    2016-09-01

    Full Text Available Energy-level densities are key for obtaining various chemical properties. In chemical kinetics, energy-level densities are used to predict thermochemistry and microscopic reaction rates. Here, an analytic energy-level density formulation is derived using inverse Laplace transformation of harmonic oscillator partition functions. Anharmonic contributions to the energy-level density are considered approximately using a literature model for the transition from harmonic to free motions. The present analytic energy-level density formulation for rigid rotor-harmonic oscillator systems is validated against the well-studied CO+O˙H system. The approximate hindered rotor energy-level density corrections are validated against the well-studied H2O2 system. The presented analytic energy-level density formulation gives a basis for developing novel numerical simulation schemes for chemical processes.

  6. IR spectroscopy of an OH hindered rotor in ZnO

    Science.gov (United States)

    Farmer, Ellen; Weiser, Philip; Stavola, Michael; Fowler, W. Beall

    2015-03-01

    An infrared absorption band at 3326 cm-1 has been assigned to H+ in an antibonding configuration in the vicinity of another defect, perhaps Ca. The 3326 cm-1 band has a distinctive dependence on temperature, consisting of several overlapping components whose intensities show thermally activated behavior over the temperature range 4K to 50K. We have measured a series of high-resolution spectra for OH and OD to determine the energy level structure of the 3326 cm-1 center and its dependence on hydrogen isotope. The results of our analysis suggest an OH hindered rotor that is reminiscent of previous results for an off-axis OD-Li center in MgO. * Permanent address: Truman State University Supported by NSF Grant DMR-1160756 and the REU program PHY-1359195.

  7. Factors hindering clinical training of students in selected nursing educational institutions in Southeastern Nigeria.

    Science.gov (United States)

    Anarado, Agnes N; Agu, Grace U; Nwonu, Eunice I

    2016-05-01

    Clinical training is an integral part of professional nursing education as it equips students with the required knowledge, skills, attitudes, and values needed for optimal practice in real-life situations. Inappropriate professional attributes have been observed among nursing graduates, while challenges to acquisition of clinical skills have been understudied in Nigeria. This study investigated system factors related to the provision of infrastructure/equipment, training/supervisory activities, and students' factors that may hinder clinical training of nursing students in two selected institutions in Southeastern Nigeria. This cross-sectional descriptive study purposively enlisted 283 students from a diploma and a degree nursing education program. Data were collected with researchers' developed questionnaire and analyzed in percentages, and means, with a mean decision criterion of students' clinical supervision; non-completion of relevant level classroom instructions and practical demonstrations before each clinical experience, inadequate equipment to practice in the clinical areas, with no preceptors to coach them at each shift (mean scores students had significantly less opportunity for return demonstration under supervision and independent practice in the laboratory; the diploma program students had significantly fewer teachers in their school and patients in their clinical area, clinical nurses as role models were not following the standard procedures in practice and students were not evaluated by supervisors at the end of each clinical experience. Identified factors in these training environments could hinder learners' interest and acquisition of professional attributes. Rectifying these situations could enhance the acquisition and display of appropriate professional performance behavior in practice by nursing graduates. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Synthesis, autoxidation and photooxidation of hindered pyrrole derivatives. Hindered pyrrolic nitroxide radicals; Synthese, autoxydation et photoxidation de pyrroles encombres radicaux nitroxydes pyrroliques encombres

    Energy Technology Data Exchange (ETDEWEB)

    Ramasseul, R. [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1969-07-01

    2,5-di-t-butyl and 2,3,5-tri-t-butyl pyrrole are prepared from pinacoline and their structure is confirmed by comparison with 2,5-di-t-butyl furan and thiophene (I.R., U.V. and N.M.R. {sup 13}C satellites observation giving J{sub 13{sub C-H}} and J{sub H{sub 3}-H{sub 4}}). The sensitized photooxidation of these hindered pyrroles gives corresponding hydroperoxides which most likely structure is determined using physical and chemical methods. Oxidation of 2,5-di-t-butyl and 2,3,5-tri-t-butyl pyrrole by hydrogen peroxide in presence of inorganic per-acid of by p-nitro-perbenzoic acid does not give the pyrrolic nitroxides in contrast with secondary amines. Some N-hydroxypyrroles are then prepared from pinacoline and ethyl pivaloyl-acetate. Their oxidation by lead dioxide gives the corresponding pyrrolic nitroxides. 2,5-di-t-butyl 3,4-di-ethoxycarbonyl pyrryl 1-oxy is isolated and studied spectroscopically (visible and U.V., E.P.R.). In marked contrast with ordinary nitroxides it does not show solvent effect. It can be compared with 2,4-di-t-butyl cyclopentadienone, a carbon analog. For both, the long wave length transition does not show the usual n - {pi}* behaviour; that is confirmed by E.P.R. Using Huckel method for pyrrolic nitroxide skeleton, it is possible to have a good interpretation of experimental data. (author) [French] Les di-t-butyl 2,5 et tri-t-butyl-2,3,5 pyrrole sont synthetises a partir de la pinacoline et leur structure confirmee par comparaison avec les di-t-butyl-2,5 furanne et thiophene (I.R., U.V. et R.M.N.: observation des satellites {sup 13}C conduisant a la mesure des J{sub 13{sub C-H}} et J{sub H{sub 3}{sub -H{sub 4}}). La photoxydation sensibilisee de ces pyrroles encombres conduit aux hydroperoxydes correspondants dont la structure la plus probable est determinee par les methodes physicochimiques. L'oxydation des di-t-butyl-2,5 et tri-t-butyl-2,3,5 pyrrole par l'eau oxygenee en presence de peracide mineral ou par l'acide p

  9. What hinders minority ethnic access to cancer genetics services and what may help?

    Science.gov (United States)

    Allford, Anna; Qureshi, Nadeem; Barwell, Julian; Lewis, Celine; Kai, Joe

    2014-07-01

    Ethnic disparities in use of cancer genetics services raise concerns about equitable opportunity to benefit from familial cancer risk assessment, improved survival and quality of life. This paper considers available research to explore what may hinder or facilitate minority ethnic access to cancer genetics services. We sought to inform service development for people of South Asian, African or Irish origin at risk of familial breast, ovarian, colorectal and prostate cancers in the UK. Relevant studies from the UK, North America and Australasia were identified from six electronic research databases. Current evidence is limited but suggests low awareness and understanding of familial cancer risk among minority ethnic communities studied. Socio-cultural variations in beliefs, notably stigma about cancer or inherited risk of cancer, are identified. These factors may affect seeking of advice from providers and disparities in referral. Achieving effective cross-cultural communication in the complex contexts of both cancer and genetics counselling, whether between individuals and providers, when mediated by third party interpreters, or within families, pose further challenges. Some promising experience of facilitating minority ethnic access has been gained by introduction of culturally sensitive provider and counselling initiatives, and by enabling patient self-referral. However, further research to inform and assess these interventions, and others that address the range of challenges identified for cancer genetics services are needed. This should be based on a more comprehensive understanding of what happens at differing points of access and interaction at community, cancer care and genetic service levels.

  10. Local characterization of hindered Brownian motion by using digital video microscopy and 3D particle tracking

    Energy Technology Data Exchange (ETDEWEB)

    Dettmer, Simon L.; Keyser, Ulrich F.; Pagliara, Stefano [Cavendish Laboratory, University of Cambridge, 19 J J Thomson Avenue, Cambridge CB3 0HE (United Kingdom)

    2014-02-15

    In this article we present methods for measuring hindered Brownian motion in the confinement of complex 3D geometries using digital video microscopy. Here we discuss essential features of automated 3D particle tracking as well as diffusion data analysis. By introducing local mean squared displacement-vs-time curves, we are able to simultaneously measure the spatial dependence of diffusion coefficients, tracking accuracies and drift velocities. Such local measurements allow a more detailed and appropriate description of strongly heterogeneous systems as opposed to global measurements. Finite size effects of the tracking region on measuring mean squared displacements are also discussed. The use of these methods was crucial for the measurement of the diffusive behavior of spherical polystyrene particles (505 nm diameter) in a microfluidic chip. The particles explored an array of parallel channels with different cross sections as well as the bulk reservoirs. For this experiment we present the measurement of local tracking accuracies in all three axial directions as well as the diffusivity parallel to the channel axis while we observed no significant flow but purely Brownian motion. Finally, the presented algorithm is suitable also for tracking of fluorescently labeled particles and particles driven by an external force, e.g., electrokinetic or dielectrophoretic forces.

  11. Whole-depth change in bovine zona pellucida biomechanics after fertilization: how relevant in hindering polyspermy?

    Directory of Open Access Journals (Sweden)

    Massimiliano Papi

    Full Text Available Polyspermy is a common problem in bovine in vitro fertilization (IVF and has a still unclear etiology. In this specie, after IVF, despite the lack of a biochemical post-fertilization hardening, the stiffness of the outer ZP layer is significantly increased. Therefore, polyspermy might be related to an incomplete or insufficient stiffening of the ZP. We obtained, by using atomic force spectroscopy in physiological conditions, a complete characterization of the biomechanical changes of the inner and outer ZP layers occurring during oocyte maturation/fertilization and correlated them to the ultrastructural changes observed by transmission electron microscopy using ruthenium red and saponin technique. In both the inner and outer ZP layers, stiffness decreased at maturation while, conversely, increased after fertilization. Contextually, at the nanoscale, during maturation both ZP layers displayed a fine filaments network whose length increased while thickness decreased. After fertilization, filaments partially recovered the immature features, appearing again shorter and thicker. Overall, the observed biomechanical modifications were substantiated by ultrastructural findings in the ZP filament mesh. In fertilized ZP, the calculated force necessary to displace ZP filaments resulted quite similar to that previously reported as generated by bovine sperm flagellum. Therefore, in bovine IVF biomechanical modifications of ZP appear ineffective in hindering sperm transit, highlighting the relevance of additional mechanisms operating in vivo.

  12. Whole-depth change in bovine zona pellucida biomechanics after fertilization: how relevant in hindering polyspermy?

    Science.gov (United States)

    Papi, Massimiliano; Brunelli, Roberto; Familiari, Giuseppe; Frassanito, Maria Cristina; Lamberti, Luciano; Maulucci, Giuseppe; Monaci, Maurizio; Pappalettere, Carmine; Parasassi, Tiziana; Relucenti, Michela; Sylla, Lakamy; Ursini, Fulvio; De Spirito, Marco

    2012-01-01

    Polyspermy is a common problem in bovine in vitro fertilization (IVF) and has a still unclear etiology. In this specie, after IVF, despite the lack of a biochemical post-fertilization hardening, the stiffness of the outer ZP layer is significantly increased. Therefore, polyspermy might be related to an incomplete or insufficient stiffening of the ZP. We obtained, by using atomic force spectroscopy in physiological conditions, a complete characterization of the biomechanical changes of the inner and outer ZP layers occurring during oocyte maturation/fertilization and correlated them to the ultrastructural changes observed by transmission electron microscopy using ruthenium red and saponin technique. In both the inner and outer ZP layers, stiffness decreased at maturation while, conversely, increased after fertilization. Contextually, at the nanoscale, during maturation both ZP layers displayed a fine filaments network whose length increased while thickness decreased. After fertilization, filaments partially recovered the immature features, appearing again shorter and thicker. Overall, the observed biomechanical modifications were substantiated by ultrastructural findings in the ZP filament mesh. In fertilized ZP, the calculated force necessary to displace ZP filaments resulted quite similar to that previously reported as generated by bovine sperm flagellum. Therefore, in bovine IVF biomechanical modifications of ZP appear ineffective in hindering sperm transit, highlighting the relevance of additional mechanisms operating in vivo.

  13. Synthesis and characterization of copolymers from hindered amines and vinyl monomers

    Directory of Open Access Journals (Sweden)

    Marcelo Aparecido Chinelatto

    2014-01-01

    Full Text Available New copolymers from hindered amines and vinyl monomers were synthesized by radical chain polymerization. To obtain polymeric HALS, acrylamide-(1ATP and acrylate-(4ATP monomers, derivatives from 2,2,6,6-tetramethylpiperidine and 2,2,6,6-tetramethyl-4-piperidinol were synthesized. The radical chain polymerization of 1ATP with styrene (Sty using 1-butanethiol (BTN resulted in a copolymer with 95 units of Sty and 15 units of 1ATP. The radical chain polymerization of 1ATP and vinyl acetate (VAc has produced only 1ATP homopolymer. In the chain polymerization of 4ATP with Sty or VAc, the hydrogen atom bonded to the nitrogen of 4ATP is labile enough to originate another radical at this site. The steric hindrance imposed by methyl groups on this bonding site hampers its reaction with other propagating species and the formation of a copolymer or network structure will be dependent on the size of the pendent group in the vinyl monomer.

  14. iPS cell-derived cardiogenicity is hindered by sustained integration of reprogramming transgenes.

    Science.gov (United States)

    Martinez-Fernandez, Almudena; Nelson, Timothy J; Reyes, Santiago; Alekseev, Alexey E; Secreto, Frank; Perez-Terzic, Carmen; Beraldi, Rosanna; Sung, Hoon-Ki; Nagy, Andras; Terzic, Andre

    2014-10-01

    Nuclear reprogramming inculcates pluripotent capacity by which de novo tissue differentiation is enabled. Yet, introduction of ectopic reprogramming factors may desynchronize natural developmental schedules. This study aims to evaluate the effect of imposed transgene load on the cardiogenic competency of induced pluripotent stem (iPS) cells. Targeted inclusion and exclusion of reprogramming transgenes (c-MYC, KLF4, OCT4, and SOX2) was achieved using a drug-inducible and removable cassette according to the piggyBac transposon/transposase system. Pulsed transgene overexpression, before iPS cell differentiation, hindered cardiogenic outcomes. Delayed in counterparts with maintained integrated transgenes, transgene removal enabled proficient differentiation of iPS cells into functional cardiac tissue. Transgene-free iPS cells generated reproducible beating activity with robust expression of cardiac α-actinin, connexin 43, myosin light chain 2a, α/β-myosin heavy chain, and troponin I. Although operational excitation-contraction coupling was demonstrable in the presence or absence of transgenes, factor-free derivatives exhibited an expedited maturing phenotype with canonical responsiveness to adrenergic stimulation. A disproportionate stemness load, caused by integrated transgenes, affects the cardiogenic competency of iPS cells. Offload of transgenes in engineered iPS cells ensures integrity of cardiac developmental programs, underscoring the value of nonintegrative nuclear reprogramming for derivation of competent cardiogenic regenerative biologics. © 2014 American Heart Association, Inc.

  15. Water Sorption and Hindered Diffusion with Different Chain Stiffness of Superabsorbent Polymer

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Myung-Suk; Lee, Dae-Young [Korea Institute of Science and Technology, Seoul (Korea, Republic of)

    2015-01-15

    Water sorption and diffusion are essential physicochemical properties of a high-performance superabsorbent polymer (SAP). We combine the Park model with the obstruction-scaling model and the water clustering in confined spaces of the polymer hydrogel. Special attention is focused on elucidating the effect of chain stiffness by considering the conformation of the polymer chain. Theoretical model parameters are determined from the best fits by simultaneous nonlinear regressions for both sorption and corrected diffusion data based on previous experiments with poly(acrylamide-co-sodium acrylate) hydrogel. Predictions show that the hindered water diffusivity leads to a sigmoid curve with relative humidity a{sub w}, where it increases monotonically up to aw{sub ≅} 0.6 due to the swelling but decreases at higher a{sub w} caused by water clustering. Water diffusion decreases with increasing chain stiffness, and the larger persistence length provides a smaller opening radius in void spaces regarding the weak elastic deformation of hydrogel under the applied stress.

  16. Natural rubber/nitrile butadiene rubber/hindered phenol composites with high-damping properties

    Directory of Open Access Journals (Sweden)

    Xiuying Zhao

    2015-10-01

    Full Text Available New natural rubber (NR/nitrile butadiene rubber (NBR/hindered phenol (AO-80 composites with high-damping properties were prepared in this study. The morphological, structural, and mechanical properties were characterized by atomic force microscopy (AFM, polarized Fourier transform infrared spectrometer (FTIR, dynamic mechanical thermal analyzer (DMTA, and a tensile tester. Each composite consisted of two phases: the NR phase and the NBR/AO-80 phase. There was partial compatibility between the NR phase and the NBR/AO-80 phase, and the NR/NBR/AO-80 (50/50/20 composite exhibited a co-continuous morphology. Strain-induced crystallization occurred in the NR phase at strains higher than 200%, and strain-induced orientation appeared in the NBR/AO-80 phase with the increase of strain from 100% to 500%. The composites had a special stress–strain behavior and mechanical properties because of the simultaneous strain-induced orientation and strain-induced crystallization. In the working temperature range of a seismic isolation bearing, the composites (especially the NR/NBR/AO-80 (50/50/20 composite presented a high loss factor, high area of loss peak (TA, and high hysteresis energy. Therefore, the NR/NBR/AO-80 rubber composites are expected to have important application as a high-performance damping material for rubber bearing.

  17. Helpful and hindering events in psychotherapy: a practice research network study.

    Science.gov (United States)

    Castonguay, Louis G; Boswell, James F; Zack, Sanno E; Baker, Sally; Boutselis, Mary A; Chiswick, Nancy R; Damer, Diana D; Hemmelstein, Neal A; Jackson, Jeffrey S; Morford, Marolyn; Ragusea, Stephen A; Roper, J Gowen; Spayd, Catherine; Weiszer, Tara; Borkovec, Thomas D; Holtforth, Martin Grosse

    2010-09-01

    This paper presents the findings of a psychotherapy process study conducted within the Pennsylvania Psychological Association Practice Research Network (PPA-PRN). The investigation was the product of a long-term collaborative effort, both in terms of the study design and implementation, between experienced clinicians of various theoretical orientations and full-time psychotherapy researchers. Based on a relatively large sample of clients seen in independent practice settings, close to 1,500 therapeutic events (described by clients and therapists as being particularly helpful or hindering) were collected. These events were coded by three independent observers using a therapy content analysis system. Among the findings, both clients and therapists perceived the fostering of self-awareness as being particularly helpful. The results also point to the importance of paying careful attention to the therapeutic alliance and other significant interpersonal relationships. The merits and difficulties of conducting scientifically rigorous and clinically relevant studies in naturalistic contexts are also discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

  18. Maximizing Community Voices to Address Health Inequities: How the Law Hinders and Helps.

    Science.gov (United States)

    Aoki, Julie Ralston; Peters, Christina; Platero, Laura; Headrick, Carter

    2017-03-01

    This paper highlights the need to apply an equity lens when assessing the impact of preemption and related legal doctrines on community health. Community autonomy to set and pursue public health priorities is an essential part of achieving health equity. Unfortunately, the priorities of organized industry interest groups often conflict with health equity goals. These groups have a history of successfully using law to limit community autonomy to pursue public health measures, most notably through preemption and related legal doctrines. We examine this phenomenon using two examples. First, we look at dental association efforts to block the spread of dental therapists in Indian Country. Native dental therapists have been improving the oral health of native people in Alaska for over a decade; yet the national and state dental associations have sought with mixed success to leverage state and federal laws to hinder other tribal governments from utilizing these providers. We compare these efforts with a restaurant association-led movement to limit what municipal governments can do to address food-based health inequities, focusing on a "model" ALEC bill that started in Ohio. Finally, we discuss how municipalities and Tribes are fighting back and continuing to pursue health equity for their communities.

  19. Hindered spin-transitions in the dissociative adsorption of O{sub 2} on Al(111)

    Energy Technology Data Exchange (ETDEWEB)

    Carbogno, Christian; Gross, Axel [Inst. of Theoretical Chemistry, University of Ulm (Germany); Behler, Joerg [Dept. of Chemistry and Applied Biosciences, ETH Zuerich (Switzerland); Reuter, Karsten [Fritz-Haber-Institut der Max- Planck-Gesellschaft, Berlin (Germany)

    2007-07-01

    The low stick ing probability for thermal O{sub 2} molecules at Al(111) has (DE) recently been related to spin selection rules, which hinder a spin transition from the initial O{sub 2} gas-phase triplet state to the singlet state of the adsorbed O atoms. A constrained density-functional theory (DFT) approach was employed to compute the potential energy surfaces (PESs) of O{sub 2} in different spin-configurations, and the lowered sticking probability was calculated when restricting the O{sub 2} molecule to motion on the spin-triplet PES only. Here, we extend these studies by considering the dissociation dynamics on multiple spin PESs, allowing transitions between them within the quantum-classical fewestswitch algorithm as recently implemented, and calculating the nonadiabatic coupling between the PESs with various quantum chemical methods. The established framework enables us to study the adsorption process in detail, both as a function of the incident kinetic energy and incidence angle. Obtaining good agreement with experiment, we critically discuss the effects of the approximate non-adiabatic couplings and the uncertainties underlying the DFT PESs.

  20. Hindered spin-transitions in the dissociative adsorption of O{sub 2} on Al(111)

    Energy Technology Data Exchange (ETDEWEB)

    Carbogno, Christian; Gross, Axel [Institut fuer Theoretische Chemie, Universitaet Ulm (Germany); Behler, Joerg [Lehrstuhl fuer Theoretische Chemie, Ruhr-Universitaet Bochum (Germany); Reuter, Karsten [Fritz-Haber-Institut der Max-Planck-Gesellschaft, Berlin (Germany)

    2008-07-01

    The low sticking probability for thermal O{sub 2} molecules at Al(111) has recently been related to spin selection rules, which hinder transitions from the initial O{sub 2} gas-phase triplet state to the singlet state of the adsorbed O atoms. A constrained DFT approach was employed to compute potential energy surfaces (PESs) of O{sub 2} in different spin-configurations from the surface, and the experimental sticking probability was qualitatively reproduced when restricting the O{sub 2} molecule to motion on the spin-triplet PES only. Here, we extend these studies by considering the dissociation dynamics on multiple spin PESs, allowing transitions between them within Tully's fewest-switches algorithm as recently implemented. The required non-adiabatic coupling elements have been derived in an ab initio fashion from the comparison between adiabatic and constrained-DFT PESs. Within this framework we obtain both good agreement with experiment for the fundamental features of the system as well as deeper insight into more peculiar characteristics of the dynamics. Based on our results, we propose experiments which can be used for the validation of our approach.

  1. The Heisenberg-Weyl algebra on the circle and a related quantum mechanical model for hindered rotation.

    Science.gov (United States)

    Kouri, Donald J; Markovich, Thomas; Maxwell, Nicholas; Bodmann, Bernhard G

    2009-07-02

    We discuss a periodic variant of the Heisenberg-Weyl algebra, associated with the group of translations and modulations on the circle. Our study of uncertainty minimizers leads to a periodic version of canonical coherent states. Unlike the canonical, Cartesian case, there are states for which the uncertainty product associated with the generators of the algebra vanishes. Next, we explore the supersymmetric (SUSY) quantum mechanical setting for the uncertainty-minimizing states and interpret them as leading to a family of "hindered rotors". Finally, we present a standard quantum mechanical treatment of one of these hindered rotor systems, including numerically generated eigenstates and energies.

  2. What hinders the development of small businesses: the view of the Murmansk Oblast entrepreneurs

    Directory of Open Access Journals (Sweden)

    Tat’yana Igorevna Barasheva

    2014-07-01

    Full Text Available In recent years there has been a slowdown in the growth rate of Russia’s sector of small and medium entrepreneurship; this issue once again brings to the fore the search for new ways and mechanisms in the management of its subjects. A necessary condition for such a search consists in focusing on the problems that hinder the development of this sector and that can be revealed exclusively in the formation of valuable and accurate information – the collective views of its representatives. In this regard, the information base for the analysis was found in the results of several studies initiated by the all-Russian public organization “OPORA Rossii” (Moscow, its regional branch in Murmansk and the Northern Chamber of Commerce and Industry; the results were obtained in the course of the questionnaire survey, which was conducted among entrepreneurs with the purpose of revealing their assessment of the terms of doing business. The generalization of the research results and information obtained by the author in cooperation with representatives of small business and workers of the Prosecutor’s Office has identified the main problems, their causes and consequences of their impact on the activity of the Murmansk Oblast business sector. In the opinion of a significant part of businessmen, such factor as business climate plays a decisive role in the creation and development of the sector in the region. Despite the complexity of the situation, entrepreneurs do not lose hope of solving their problems and see the solution to the problem in efficient work of the regional and municipal authorities. The author’s conclusions may become a reference point for further reforms in the sphere of management of small enterprises in the Murmansk Oblast

  3. Decline of Phosphotransfer and Substrate Supply Metabolic Circuits Hinders ATP Cycling in Aging Myocardium.

    Directory of Open Access Journals (Sweden)

    Emirhan Nemutlu

    Full Text Available Integration of mitochondria with cytosolic ATP-consuming/ATP-sensing and substrate supply processes is critical for muscle bioenergetics and electrical activity. Whether age-dependent muscle weakness and increased electrical instability depends on perturbations in cellular energetic circuits is unknown. To define energetic remodeling of aged atrial myocardium we tracked dynamics of ATP synthesis-utilization, substrate supply, and phosphotransfer circuits through adenylate kinase (AK, creatine kinase (CK, and glycolytic/glycogenolytic pathways using 18O stable isotope-based phosphometabolomic technology. Samples of intact atrial myocardium from adult and aged rats were subjected to 18O-labeling procedure at resting basal state, and analyzed using the 18O-assisted HPLC-GC/MS technique. Characteristics for aging atria were lower inorganic phosphate Pi[18O], γ-ATP[18O], β-ADP[18O], and creatine phosphate CrP[18O] 18O-labeling rates indicating diminished ATP utilization-synthesis and AK and CK phosphotransfer fluxes. Shift in dynamics of glycolytic phosphotransfer was reflected in the diminished G6P[18O] turnover with relatively constant glycogenolytic flux or G1P[18O] 18O-labeling. Labeling of G3P[18O], an indicator of G3P-shuttle activity and substrate supply to mitochondria, was depressed in aged myocardium. Aged atrial myocardium displayed reduced incorporation of 18O into second (18O2, third (18O3, and fourth (18O4 positions of Pi[18O] and a lower Pi[18O]/γ-ATP[18 O]-labeling ratio, indicating delayed energetic communication and ATP cycling between mitochondria and cellular ATPases. Adrenergic stress alleviated diminished CK flux, AK catalyzed β-ATP turnover and energetic communication in aging atria. Thus, 18O-assisted phosphometabolomics uncovered simultaneous phosphotransfer through AK, CK, and glycolytic pathways and G3P substrate shuttle deficits hindering energetic communication and ATP cycling, which may underlie energetic

  4. Decline of Phosphotransfer and Substrate Supply Metabolic Circuits Hinders ATP Cycling in Aging Myocardium.

    Science.gov (United States)

    Nemutlu, Emirhan; Gupta, Anu; Zhang, Song; Viqar, Maria; Holmuhamedov, Ekhson; Terzic, Andre; Jahangir, Arshad; Dzeja, Petras

    2015-01-01

    Integration of mitochondria with cytosolic ATP-consuming/ATP-sensing and substrate supply processes is critical for muscle bioenergetics and electrical activity. Whether age-dependent muscle weakness and increased electrical instability depends on perturbations in cellular energetic circuits is unknown. To define energetic remodeling of aged atrial myocardium we tracked dynamics of ATP synthesis-utilization, substrate supply, and phosphotransfer circuits through adenylate kinase (AK), creatine kinase (CK), and glycolytic/glycogenolytic pathways using 18O stable isotope-based phosphometabolomic technology. Samples of intact atrial myocardium from adult and aged rats were subjected to 18O-labeling procedure at resting basal state, and analyzed using the 18O-assisted HPLC-GC/MS technique. Characteristics for aging atria were lower inorganic phosphate Pi[18O], γ-ATP[18O], β-ADP[18O], and creatine phosphate CrP[18O] 18O-labeling rates indicating diminished ATP utilization-synthesis and AK and CK phosphotransfer fluxes. Shift in dynamics of glycolytic phosphotransfer was reflected in the diminished G6P[18O] turnover with relatively constant glycogenolytic flux or G1P[18O] 18O-labeling. Labeling of G3P[18O], an indicator of G3P-shuttle activity and substrate supply to mitochondria, was depressed in aged myocardium. Aged atrial myocardium displayed reduced incorporation of 18O into second (18O2), third (18O3), and fourth (18O4) positions of Pi[18O] and a lower Pi[18O]/γ-ATP[18 O]-labeling ratio, indicating delayed energetic communication and ATP cycling between mitochondria and cellular ATPases. Adrenergic stress alleviated diminished CK flux, AK catalyzed β-ATP turnover and energetic communication in aging atria. Thus, 18O-assisted phosphometabolomics uncovered simultaneous phosphotransfer through AK, CK, and glycolytic pathways and G3P substrate shuttle deficits hindering energetic communication and ATP cycling, which may underlie energetic vulnerability of aging

  5. Helping or hindering: the role of nurse managers in the transfer of practice development learning.

    Science.gov (United States)

    Currie, Kay; Tolson, Debbie; Booth, Jo

    2007-09-01

    This paper reports selected findings from a recent PhD study exploring how graduates from a BSc Specialist Nursing programme, with an NMC-approved Specialist Practitioner Qualification, engage in practice development during their subsequent careers. The UKCC (1998) defines specialist practice as requiring higher levels of judgement, discretion and decision-making, with leadership in clinical practice development forming a core dimension of this level of practice. However, there is little evidence in the published literature that describes or evaluates the practice development role of graduate specialist practitioners. This study applied a modified Glaserian approach to grounded theory methods. A preliminary descriptive survey questionnaire was posted to all graduates from the programme, response rate of 45% (n=102). From these respondents, theoretical sampling decisions directed the selection of 20 participants for interview, permitting data saturation. The grounded theory generated by this study discovered a basic social process labelled 'making a difference', whereby graduate specialist practitioners are increasingly able to impact in developing patient care at a strategic level by coming to own the identity of an expert practitioner (Currie, 2006). Contextual factors strongly influence the practitioner journey, with organizational position and other people presenting enabling or blocking conditions. The line manager plays a crucial role in helping or hindering graduate specialist practitioners to transfer their learning to the clinical setting and become active in practice development. Recommendations to enhance managerial support for the practice development role of graduate specialist practitioners are proposed. ADDING TO CURRENT KNOWLEDGE: This work adds to currently limited knowledge of the graduate specialist practitioners' role in the leadership of clinical practice development. In addition, the findings emphasize the potential influence of the workplace

  6. Platinum-Catalyzed Selective Hydration of Hindered Nitriles and Nitriles with Acid- or Base-Sensitive Groups

    NARCIS (Netherlands)

    Jiang, Xiao-bin; Minnaard, Adriaan J.; Vries, Johannes G. de; Feringa, Bernard

    2004-01-01

    Hindered tertiary nitriles can be hydrolyzed under neutral and mild conditions to the corresponding amides using platinum(II) catalysts with dimethylphosphine oxide or other secondary phosphine oxides (SPOs, phosphinous acids) as ligands. We have found that this procedure also works well for

  7. Determination of a Polymeric Hindered Amine Light Stabilizer in Polypropylene Formulated with Magnesium Hydroxide Flame Retardant by Reactive Thermal Desorption-Gas Chromatography

    National Research Council Canada - National Science Library

    TAGUCHI, Yoshihiko; ISHIDA, Yasuyuki; OHTANI, Hajime; BEKKU, Hiroyuki; SERA, Masaya

    2004-01-01

    A polymeric hindered amine light stabilizer (HALS), Tinuvin 622 (MW = 4000), in PP materials formulated with a magnesium hydroxide flame retardant was determined by reactive thermal desorption (RTD...

  8. Self-Reported Hindering Health Complaints of Community-Dwelling Older Persons: A Cross-Sectional Study.

    Directory of Open Access Journals (Sweden)

    Sophie C E van Blijswijk

    Full Text Available Proactive care for community-dwelling older persons targeting self-reported hindering health complaints might prevent a decline in function. We investigated the spectrum of self-reported hindering complaints of community-dwelling older persons, the association with functional outcomes, and help-seeking behavior for these complaints.Within the ISCOPE trial, participants (aged ≥75 years received the ISCOPE screening questionnaire, including the open-ended question "At the moment, which health complaints limit you the most in your day-to-day life?". After coding the answers with the ICPC-1-NL, we examined the prevalence and the association between the number and type of complaints and functional outcomes (Groningen Activities Restriction Scale, quality of life measured on Cantril's Ladder, Mini-Mental State Examination, Geriatric Depression Scale-15, and De Jong Gierveld Loneliness Scale. Electronic patient registers were searched for the most reported complaints.7285 participants (median age: 81.0 years [IQR 77.8-85.3], 38.6% males reported 13,524 hindering complaints (median 1, range 0-18; 32.7% reported no complaints. Participants mostly reported problems with walking/standing (22.1%, pain (20.8% or weakness/tiredness (8.5%. These complaints were mentioned in the electronic patient registers in 28.3%, 91.3% and 55.5%, respectively. Higher numbers of hindering complaints were related to poorer scores on the number of domains with problems, Cantril's Ladder for quality of life, Groningen Activities Restriction Scale, Geriatric Depression Scale, and De Jong Gierveld Loneliness Scale. Self-reported weakness, problems with walking/standing, visual limitations, cognitive problems, dyspnea and back complaints were associated with poorer scores on the number of domains with problems, Groningen Activities Restriction Scale, MMSE or Geriatric Depression Scale.One third of the participants reported no hindering complaints. Problems with walking

  9. Registered Nurses' experiences of patient participation in hospital care: supporting and hindering factors patient participation in care.

    Science.gov (United States)

    Oxelmark, Lena; Ulin, Kerstin; Chaboyer, Wendy; Bucknall, Tracey; Ringdal, Mona

    2017-07-04

    Promoting patient participation in care is an international priority identified by the World Health Organization and various national bodies around the world and an important aspect of person-centred care. The aim of this study was to describe Registered Nurses' experiences with patient participation in nursing care including their barriers and facilitators for participation. The study setting was a University Hospital in Sweden. Interviews were conducted with twenty Registered Nurses working at medical wards in 2013. Thematic data analysis was used to analyse the transcribed interview data. Twenty nurses from four wards in two hospitals were included. Five themes emerged from the analysis including listening to the patient, engaging the patient, relinquishing some responsibility, sharing power and partnering with patients. The core theme 'partnering with patients' was enacted when nurses listened to and engaged patients and when they relinquished responsibility and shared power with patients. In addition, hindering and facilitating factors to participation were identified, such as patients wanted to take on a passive role, lack of teamwork which participants understood would enhance interprofessional understanding and improve patient safety. Patient participation was hindered by medical jargon during the ward round, there was a risk of staff talking over patients' heads but sometimes inevitable having conversations at the patient's bedside. However, nurses preferred important decisions to be made away from bedside. It all came down to partnering with the patient and participants described how they made an effort to respect the patients' view and accept patient as a part of the care team. Identified hindering factors for participation were lack of teamwork, patients' taking on passive roles and communication during ward rounds having conversations at the patient's bedside. Nurses wished for a change but lacked strategies on how. Nurses preferred important decisions

  10. An S(N)Ar approach to sterically hindered ortho-alkoxybenzaldehydes for the synthesis of olefin metathesis catalysts.

    Science.gov (United States)

    Engle, Keary M; Luo, Shao-Xiong; Grubbs, Robert H

    2015-04-17

    A three-step procedure has been developed for preparing ortho-alkoxybenzaldehydes from ortho-fluorobenzaldehydes that tolerates the use of sterically hindered sodium alkoxide nucleophiles. The protocol is modular and operationally convenient. The ortho-alkoxybenzaldehyde products can be converted in one additional step to ortho-alkoxystyrenes by a Wittig reaction. These styrenes are precursors to the chelating benzylidene moiety in a proposed series of novel ruthenium complexes for use in olefin metathesis. Chelation with three representative styrenes has been demonstrated.

  11. Origin of Coverage Dependence in Photoreactivity of Carboxylate on TiO2(110): Hindering by Charged Coadsorbed Hydroxyls

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zhitao; Henderson, Michael A.; Lyubinetsky, Igor

    2015-09-30

    The influence of reactant coverage on photochemical activity was explored using scanning tunneling microscopy (STM) and ultraviolet photoelectron spectroscopy (UPS). We observed diminished reactivity of carboxylate species (trimethyl acetate, TMA) on TiO2(110) as a function of increasing coverage. This effect was not linked to intermolecular interactions of TMA but to the accumulation of the coadsorbed bridging hydroxyls (HOb) deposited during (thermal) dissociative adsorption of the parent, trimethylacetic acid (TMAA). Confirmation of the hindering influence of HOb groups was obtained by the observation that HOb species originated from H2O dissociation at O-vacancy sites have a similar hindering effect on TMA photochemistry. Though HOb’s are photoinactive on TiO2(110) under ultrahigh vacuum conditions, UPS results show that these sites trap photoexcited electrons, which in turn likely (electrostatically) attract and neutralize photoexcited holes, thus suppressing the hole-mediated photoreactivity of TMA. This negative influence of surface hydroxyls on hole-mediated photochemistry is likely a major factor in other anaerobic photochemical processes on reducible oxide surfaces.

  12. Facilitating and hindering factors for coping with the experience of having a child with cancer: A Lebanese perspective.

    Science.gov (United States)

    Doumit, Myrna A A; Khoury, May Naifeh

    2017-01-01

    Families with a child with cancer face significant emotional and psychosocial stressors. The frequency of childhood cancer is increasing in Lebanon with more than 282 children diagnosed each year. This condition is reported to evoke a range of challenging emotions for parents, yet no studies have been conducted on the facilitating and hindering factors that affect Lebanese parents coping with a child with cancer. The purpose of the study was to gain an in-depth understanding of factors facilitating and hindering coping methods of Lebanese parents with a child with cancer. The study followed purposeful sampling and saturation principles in which 12 parents (mother or father) of a child were interviewed. Data were analyzed following the Utrecht School of phenomenology. Helpful and harmful experiences emerged through the coding process. The enabling factors were social/family support; talking about it; strong religious beliefs; and the communication style of health workers. On the other hand, the deterring factors were the waiting time and the hospital stay; changes in the couple's relationship; and sibling rivalry. These results could be used as the basis for additional research aimed at developing a structured approach to care that endorses the coping processes of Lebanese parents with a child with cancer. Nursing and medical staff need to be conscious of parents' coping strategies and their impact on family dynamics and the relationship between the family and the health care team.

  13. Factors that hinder community participation in developing and implementing comprehensive council health plans in Manyoni District, Tanzania

    Directory of Open Access Journals (Sweden)

    Emmanuel G. Kilewo

    2015-06-01

    Full Text Available Background: Decentralization of public health planning is proposed to facilitate public participation in health issues. Health Sector Reform in Tanzania places emphasis on the participation of lower level health facilities and community in health planning process. Despite availability of policies, guidelines, and community representative organs, actual implementation of decentralization strategies is poorly achieved. This study intended to find out factors that hinder community participation in developing and implementing Comprehensive Council Health Plan (CCHP. Materials and methods: A qualitative approach was conducted in this study with key informants from Health Facility Governing Committees (HFGC, Council Health Service Board (CHSB, and Council Health Management Team (CHMT. Data were collected using in-depth interviews. Data generated were analyzed for themes and patterns. Results: Factors that hindered community participation included lack of awareness on the CCHP among HFGC members, poor communication and information sharing between CHMT and HFGC, unstipulated roles and responsibilities of HFGC, lack of management capacity among HFGC members, and lack of financial resources for implementing HFGC activities. Conclusions: The identified challenges call for policy makers to revisit the decentralization by devolution policy by ensuring that local governance structures have adequate resources as well as autonomy to participate in planning and managing CCHP in general and health facility plans in particular.

  14. Competitive and hindering effects of natural organic matter on the adsorption of MTBE onto activated carbons and zeolites

    Energy Technology Data Exchange (ETDEWEB)

    Hung, H.W.; Lin, T.F.; Baus, C.; Sacher, F.; Brauch, H.J. [National Cheng Kung University, Tainan (Taiwan). Dept. of Environmental Engineering

    2005-12-15

    Equilibrium and kinetic adsorption of methyl tert-butyl ether (MTBE) onto three coal-based activated carbons, one coconut-based activated carbon, and two zeolites are elucidated in this study. Natural organic matter (NOM) and MTBE competed for the adsorption of activated carbons to different extents. The Ideal Adsorbed Solution Theory (lAST) combined with the equivalent background compound (EBC) model can adequately describe the NOM competition and predict the isotherms of MTBE onto the activated carbons. No competitive adsorption was observed for one of the zeolites, mordenite, due to the molecular effect. Besides, the aperture size, and the SiO{sub 2}/Al{sub 2}O3 ratio of the zeolite may also play an important role in the adsorption of MTBE from the aqueous phase. The surface diffusion model accurately simulated the transport of MTBE within the adsorbents employed in different water matrices. For all the activated carbons tested, the surface diffusivity of MTBE in natural water was nearly equal to that in deionized water, indicating that no apparently hindering effect occurs. A much slower adsorption kinetic of mordenite in natural water was observed since the opening apertures on mordenite may be appreciably hindered and blocked by NOM.

  15. New insights into the mechanism of amine/nitroxide cycling during the hindered amine light stabilizer inhibited oxidative degradation of polymers

    National Research Council Canada - National Science Library

    Gryn’ova, Ganna; Ingold, Keith; Coote, Michelle L

    2012-01-01

    ... of the present work, including that of N-alkyl hindered amine light stabilizer activation. We find that most of the literature nitroxide regeneration cycles should be discarded on either kinetic or thermodynamic grounds...

  16. Hindering factors and suggestions related to organ donation decisions: perspective of the Taiwan Ali-Shan Tsou aboriginal tribe.

    Science.gov (United States)

    Chen, A N; Chen, K F; Chang, P C; Shih, F Jong; Chen, C R; Shih, F-Jin; Huang, C-Y

    2014-05-01

    Ali-San Tsou (AST) is one of leading aboriginal tribes in Taiwan with traditional godly beliefs related to life and death. Lacking related knowledge, health professionals (HPs) often failed to help them reach good dying or organ donation (OD). This study aimed to explore hindering factors and suggestions related to OD for good dying from Taiwan AST's own perspective. An explorative qualitative design was employed using a purposive sample of the AST tribes from Taiwan. Data were collected with AST residents by face-to-face interviews and analyzed by content analysis. Thirty AST residents (16 females and 14 males) with ages ranging from 28 to 78 (mean, 54.5) years completed interviews. Of them, 85% reported various diseases. In this study 73% were Catholics and Christians, 17% held traditional godly believes, and 10% had no religious affiliation. Eight hindering factors were reported: (1) limited information about organs and OD; (2) no qualified organs for donation; (3) worry about lack of forgiveness by ancestors; (4) tribe elders who might not accept concept of OD; (5) intact bodies were required at home during spirit-companion rituals; (6) earth burial with intact bodies was preferred; (7) bodies due to accidental and bad death were impermissible for OD; and (8) worry about possession by the donor's spirit. Seven suggestions were also reported for HPs to enhance AST's OD decisions: (1) starting with friendship and a caring relationship; (2) providing spiritual support from reverent religions; (3) stressing good deeds and honoring tribe folks by OD; (4) avoiding accidental/bad death; (5) providing relevant modern medical knowledge of human organs and OD; (6) introducing OD as part of a good-dying care plan; and (7) demonstrating a respectful discussion mindset about OD. Eight hindering factors and 7 types of suggestions for enhancing AST aboriginal people's OD decisions were first explored in this project. In the future, HPs are encouraged to invite AST to share

  17. GENERAL EQUATION OF THE HYDRAULIC FRICTION LAW FOR HINDERED FALLING OF AN INDIVIDUAL BALL AND FLUID MOTION IN GRANULAR LAYERS

    Directory of Open Access Journals (Sweden)

    M. V. Krautsov

    2015-01-01

    Full Text Available The article presents the results of a research into various hydromechanical processes such as hindered falling of an individual ball in a liquid; suspension of a homogeneous monodispersed granular layer with ascending fluid flow; homogeneous liquid filtration in a porous granular layer. The authors generalize the results of theoretical and experimental studies, employ the theory of similarity, and establish that the laws of hydraulic friction for the mentioned hydromechanical processes share the common ground described by one general equation that provides basis for obtaining the individual formulae computing the studied hydromechanical processes. The formulae appear in dimensionless similitude parameters that reflect correlation of the essential action forces.The presented scientific results contribute to the theory development of the applied hydromechanical phenomena and the new obtained formulae enable enhancement of the calculation procedures for structures and installations that realize the studied hydraumechanical processes. Thus, the research results for the hindered falling of an individual ball in a liquid can apply in viscosimetry techniques and in handling the problems related to calculations of various movement types and separate units in technologies realizing the hydraulic processes of hindered falling of individual balls in liquids.Fluidization processes (pseudo-liquefaction of the granular layers enjoy wide application in various segments of industry for instance in chemical engineering at adsorption, desorption, dissolution, dealkalization, ablution. A new general calculating formula incipiency provides a possibility for technological computations realization under any operational mode. The filtration process is used in industry as well as occurs in nature, for example, in movement of the ground water. At present, the basis for calculating techniques is the monomial Darcy formula defining the filtering rate as function of the

  18. The combination effect of hindered amine light stabilizers with UV absorbers on the radiation resistance of polypropylene

    Science.gov (United States)

    Jia, Haishun; Wang, Huiliang; Chen, Wenxiu

    2007-07-01

    The UV absorber 2-(2'-hydroxy-3',5'-dipentyl-phenyl) benzotriazole (Tinuvin 328) shows excellent stabilizing effectiveness in the γ-ray-induced degradation of polypropylene (PP). Antagonism was observed when hindered amine light stabilizers were used with benzotriazole type UV absorbers. The carbonyl index and hydroxyl index, the hydroperoxide concentration, the mass change and the relative concentration of alkyl free radicals of irradiated samples were measured. Tinuvin 328 could effectively inhibit the formation of alkyl free radicals in PP under γ-irradiation, and it is possibly the fundamental reason for its high stabilizing efficiency. A mechanism of dissipating radiation energy for Tinuvin 328 was proposed. Some reactions yet unknown between the two stabilizers decreased their stabilizing effectiveness.

  19. What community characteristics help or hinder rural communities in becoming age-friendly? Perspectives from a Canadian prairie province.

    Science.gov (United States)

    Spina, John; Menec, Verena H

    2015-06-01

    Age-friendly initiatives are increasingly promoted as a policy solution to healthy aging, The primary objective of this article was to examine older adults' and key stakeholders' perceptions of the factors that either help or hinder a community from becoming age-friendly in the context of rural Manitoba, a Canadian prairie province. Twenty-four older adults and 17 key informants completed a qualitative interview. The findings show that contextual factors including size, location, demographic composition, ability to secure investments, and leadership influence rural communities' ability to become age-friendly. Government must consider the challenges these communities face in becoming more age-friendly and develop strategies to support communities. © The Author(s) 2013.

  20. Direct synthesis of highly substituted 2-cyclohexenones and sterically hindered benzophenones based on a [5C + 1C] annulation.

    Science.gov (United States)

    Fu, Zhenqian; Wang, Mang; Dong, Ying; Liu, Jun; Liu, Qun

    2009-08-21

    The regiospecific [5C + 1C] annulation of readily available alpha-alkenoyl ketene (S,S)-acetals 1 with aryl methyl ketones 2, the less active methylene compounds, has been developed. Upon treatment of 1 with 2 in the presence of t-BuOK in DMF at room temperature, highly substituted 2-cyclohexenones 3 were synthesized in high to excellent diastereoselectivities with high yields. On the basis of this strategy, sterically hindered benzophenones 4 were conveniently prepared via the iodonation-aromatization of 2-cyclohexenones 3 with I(2) in MeONa/MeOH basic medium. Furthermore, benzophenones 4 were also obtained directly from 1 and 2 following a sequential [5 + 1] annulation-iodonation-aromatization procedure in a one-pot operation.

  1. Can Altruism Hinder Cooperation?

    OpenAIRE

    Keisuke Nakao

    2008-01-01

    This note considers the effects of altruism on cooperation in the context of a repeated Prisoner's Dilemma. Altruism has two conflicting impacts on cooperation: One is to reduce the temptation for defection the other is to make the future punishment ineffective. The total effect of altruism hinges on the shape of players'' cost functions.

  2. What factors hinder the decision-making process for women with cancer and contemplating fertility preservation treatment?

    Science.gov (United States)

    Jones, Georgina; Hughes, Jane; Mahmoodi, Neda; Smith, Emily; Skull, Jonathan; Ledger, William

    2017-07-01

    Although fertility preservation (FP) treatment options have increased, the existing evidence suggests that many women with cancer do not feel well supported in making these decisions, but find them stressful and complex and fail to take up fertility care at this crucial time. Whilst existing reviews have all made important contributions to our understanding of the FP decision-making process, none of them examine solely and specifically these processes for women of reproductive age with a diagnosis of any cancer, leaving a gap in the knowledge base. Given the expectation that care is patient-centred, our review aims to address this gap which may be of help to those managing patients struggling to make difficult decisions in the often brief period before potentially sterilizing cancer treatment is started. Underpinning this narrative review was the question 'What factors hinder the decision-making process for women with any cancer and contemplating FP treatment?' Our objectives were to (i) assess and summarize this existing literature, (ii) identify the factors that hinder this decision-making process, (iii) explore to what extent these factors may differ for women choosing different methods of FP and (iv) make recommendations for service delivery and future research. A systematic search of the medical and social science literature from the 1 January 2005 up to the end of January 2016 was carried out using three electronic databases (Web of Science (PubMed), Ovid SP Medline and CINAHL via Ebsco). Included in the review were quantitative, qualitative and mixed-method studies. Reference lists of relevant papers were also hand searched. From the 983 papers identified, 46 papers were included. Quality assessment was undertaken using the Mixed Methods Appraisal Tool and thematic analysis was used to analyse the data. From the analysis, 6 key themes with 15 sub-themes emerged: (i) fertility information provision (lack of information, timing of the information, patient

  3. What hinders teachers in using computer and video games in the classroom? Exploring factors inhibiting the uptake of computer and video games.

    Science.gov (United States)

    Baek, Young Kyun

    2008-12-01

    The purpose of this study is to identify factors inhibiting teachers' use of computer and video games in the classroom setting and to examine the degree to which teaching experience and gender affect attitudes toward using games. Six factors that hinder teachers' use of games in the classroom were discovered: Inflexibility of curriculum, Negative effects of gaming, Students' lack of readiness, Lack of supporting materials, Fixed class schedules, and Limited budgets. Lack of supporting material, Fixed class schedules, and Limited budgets were factors that female teachers believed to be more serious obstacles to game use in the classroom than male teachers did. Experienced teachers, more so than inexperienced teachers, believed that adopting games in teaching was hindered by Inflexibility of curriculum and Negative effects of gaming. On the other hand, inexperienced teachers, more so than experienced teachers, believed that adopting games in teaching is less hindered by Lack of supporting materials and Fixed class schedules.

  4. Excess titanium dioxide nanoparticles on the cell surface induce cytotoxicity by hindering ion exchange and disrupting exocytosis processes

    Science.gov (United States)

    Wang, Yanli; Yao, Chenjie; Li, Chenchen; Ding, Lin; Liu, Jian; Dong, Peng; Fang, Haiping; Lei, Zhendong; Shi, Guosheng; Wu, Minghong

    2015-07-01

    To date, considerable effort has been devoted to determine the potential toxicity of nanoparticles to cells and organisms. However, determining the mechanism of cytotoxicity induced by different types of nanoparticles remains challenging. Herein, typically low toxicity nanomaterials were used as a model to investigate the mechanism of cytotoxicity induced by low toxicity nanomaterials. We studied the effect of nano-TiO2, nano-Al2O3 and nano-SiO2 deposition films on the ion concentration on a cell-free system simulating the cell membrane. The results showed that the ion concentration of K+, Ca2+, Na+, Mg2+ and SO42- decreased significantly following filtration of the prepared deposition films. More specifically, at a high nano-TiO2 concentration (200 mg L-1) and a long nano-TiO2 deposition time (48 h), the concentration of Na+ decreased from 2958.01 to 2775.72, 2749.86, 2757.36, and 2719.82 mg L-1, respectively, for the four types of nano-TiO2 studied. Likewise, the concentration of SO42- decreased from 38.83 to 35.00, 35.80, 35.40, and 35.27 mg L-1, respectively. The other two kinds of typical low toxicity nanomaterials (nano-Al2O3 and nano-SiO2) have a similar impact on the ion concentration change trend. Adsorption of ions on nanoparticles and the hydrated shell around the ions strongly hindered the ions through the nanoparticle films. The endocytosed nanoparticles could be released from the cells without inducing cytotoxicity. Hindering the ion exchange and disrupting the exocytosis process are the main factors that induce cytotoxicity in the presence of excess nano-TiO2 on the cell surface. The current findings may offer a universal principle for understanding the mechanism of cytotoxicity induced by low toxicity nanomaterials.To date, considerable effort has been devoted to determine the potential toxicity of nanoparticles to cells and organisms. However, determining the mechanism of cytotoxicity induced by different types of nanoparticles remains challenging

  5. Student Academic Performance: The Role of Motivation, Strategies, and Perceived Factors Hindering Liberian Junior and Senior High School Students Learning

    Directory of Open Access Journals (Sweden)

    Charles Gbollie

    2017-01-01

    Full Text Available The nature of motivation and learning strategy use is vital to improving student learning outcomes. This study was intended to explore the motivational beliefs and learning strategy use by Liberian junior and senior high school students in connection with their academic performance. It also solicited students’ self-reports about presumed factors hindering their learning. Utilizing a cross-sectional quantitative research design, 323 participants took part in the study from 2 counties. Motivated Strategies for Learning Questionnaire (MSLQ was adapted and 12 potential learning hindrances were identified and used as instruments. Data analyses were conducted using SPSS 17.0. The results showed the motivational belief component of extrinsic goal orientation as the most preferred belief and test anxiety was the least possessed belief. Rehearsal strategies were found to be the most frequently used, while help seeking was reported to be the least strategy considered. The result also showed significant relationships between the two constructs. In addition, the study found some learning hindrances. A number of conclusions as well as some practical recommendations for action relative to the improvement of student performance have been advanced.

  6. Factors hindering acceptance of HIV/AIDS voluntary counseling and testing (VCT) among youth in Kwara State, Nigeria.

    Science.gov (United States)

    Yahaya, L A; Jimoh, A A G; Balogun, O R

    2010-09-01

    HIV/AIDS has become a source of concern all over the world. The concern cannot be isolated from the devastating effects of HIV/AIDS on economic, social, political and technological development of any nation with a high prevalence rate Nigeria is one of the countries with HIV/AIDS prevalence rate of over 4%. Despite this challenge, the patronage of Voluntary Counseling and Testing (VCT) is still very low. This study therefore examined the factors hindering the acceptance of VCT as expressed by youths in Kwara State. A total of 600 youths from the three Senatorial districts in the State were involved in the study. A survey instrument designed by the researchers was used to collect relevant information from the respondents. Among others, the study identified ignorance, poverty, inadequate number of VCT centres, stigma and discrimination as major factors responsible for the low patronage of VCT centres in Kwara State. Gender and religion had no significant influence on the respondents' views while place of residence had significant influence. The implications of the findings to medical practice and counseling were identified and discussed.

  7. Molecular Adsorption, Hindered Rotation, and Species Separation of H2/SrTiO3(001)

    Science.gov (United States)

    Shimizu, Koji; Diño, Wilson Agerico; Nakanishi, Hiroshi; Kasai, Hideaki; Fukutani, Katsuyuki; Yajima, Ayako

    2017-07-01

    We investigated the interaction of H2 with SrTiO3(001) using density functional theory based total energy calculations. We found that the H2 adsorption strongly depends on the polar orientation of the H-H bond, and the preferred configuration determined by the ionic species of the atom at the adsorption site (i.e., cation or anion). From the calculated potential energy surfaces, we determined the corresponding hindered rotational states of the adsorbed H2. The calculated wave functions indicate preferential adsorption on top of the O site of an SrO-terminated surface, with the H-H bond oriented perpendicular to the surface. On a TiO2-terminated surface, the H2 adsorption occurs on top of the Ti site, with the H-H bond oriented parallel to the surface. The differences in the rotational state dependent desorption temperature suggest the possibility of species separation of H2, especially on the SrO-terminated surface.

  8. Oroxylin A inhibits hemolysis via hindering the self-assembly of α-hemolysin heptameric transmembrane pore.

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    Jing Dong

    Full Text Available Alpha-hemolysin (α-HL is a self-assembling, channel-forming toxin produced by most Staphylococcus aureus strains as a 33.2-kDa soluble monomer. Upon binding to a susceptible cell membrane, the monomer self-assembles to form a 232.4-kDa heptamer that ultimately causes host cell lysis and death. Consequently, α-HL plays a significant role in the pathogenesis of S. aureus infections, such as pneumonia, mastitis, keratitis and arthritis. In this paper, experimental studies show that oroxylin A (ORO, a natural compound without anti-S. aureus activity, can inhibit the hemolytic activity of α-HL. Molecular dynamics simulations, free energy calculations, and mutagenesis assays were performed to understand the formation of the α-HL-ORO complex. This combined approach revealed that the catalytic mechanism of inhibition involves the direct binding of ORO to α-HL, which blocks the conformational transition of the critical "Loop" region of the α-HL protein thereby inhibiting its hemolytic activity. This mechanism was confirmed by experimental data obtained from a deoxycholate-induced oligomerization assay. It was also found that, in a co-culture system with S. aureus and human alveolar epithelial (A549 cells, ORO could protect against α-HL-mediated injury. These findings indicate that ORO hinders the lytic activity of α-HL through a novel mechanism, which should facilitate the design of new and more effective antibacterial agents against S. aureus.

  9. Long-term repeated daily use of intragastric gavage hinders induction of oral tolerance to ovalbumin in mice.

    Science.gov (United States)

    Kinder, Jeremy M; Then, Jenny E; Hansel, Patrick M; Molinero, Luciana L; Bruns, Heather A

    2014-10-01

    Oral tolerance is dependent on the complex architecture of the mucosal system of the gastrointestinal tract, its associated lymphoid tissue, and specialized immune cells. Changes in this architecture or the failure of any of its components may hinder the generation of oral tolerance. The larynx and esophagus are the gateway to the gastrointestinal tract, serving as the site of oral antigen introduction to the immune system and may have an important role in establishing tolerance. Intragastric gavage is a common method for precise oral dosing of rodents, particularly in studies examining oral tolerance. However, complications such as esophageal trauma can occur and induce complicating factors that affect experimental outcomes. In this study, we examined the esophageal epithelium for alterations resulting from long-term repeated daily use of intragrastric gavage and its effect on the induction of tolerance. Tolerance to ovalbumin could not be achieved after using intragastric gavage for 14 d or more consecutively to introduce ovalbumin. However, tolerance was achieved when intragastric gavage was used for shorter durations. After 14 d of gavage, disruption of the esophageal mucosal epithelium indicative of an inflammatory pathology, cellular influx into the esophageal tissue, and proinflammatory cytokines in the tissue were absent, and the CD3(+) cell population in the esophageal epithelium decreased. These findings provide initial evidence for the important roles of esophageal integrity and cellular populations in the induction of oral tolerance and suggest possible immunologic sequelae in experiments involving the use of extended, repeated gavage.

  10. Antivertiginous drug therapy does not hinder the efficacy of individualized vibrotactile neurofeedback training for vestibular rehabilitation - a randomized trial.

    Science.gov (United States)

    Basta, Dietmar; Borsellino, Liliana; Ernst, Arne

    2017-12-01

    Vestibular rehabilitation using individualized vibrotactile neurofeedback training (IVNT) can lead to significant improvement in the postural stability of patients with vestibular symptoms of different origins. However, some of these patients have complex, severe dizziness, meaning that a pharmacological pretreatment or parallel (to vestibular rehabilitation) treatment can help them perform the rehabilitation exercises. Hence, the present study investigated the influence of a pharmacological treatment on the efficacy of vibrotactile neurofeedback training in patients with chronic, noncompensated vestibulopathies. All participants performed IVNT for ∼10 min each day for 2 weeks. In addition, every second participant was selected randomly to receive oral medication (20 mg cinnarizine and 40 mg dimenhydrinate per tablet), taking three tables per day. Trunk and ankle sway and postural stability were measured. In addition, the dizziness handicap inventory was evaluated immediately before training on the last day of training and 6 months after training. After the 10-day period of IVNT, both groups showed a statistically significant improvement in all parameters tested. A follow-up analysis after 6 months showed a long-term efficacy for the IVNT, that is, the patients remained significantly improved in their postural stability. The antivertiginous therapy did not hinder the efficacy of the IVNT. The present results indicate that IVNT even in combination with an antivertiginous drug therapy is an effective treatment regime for patients with disabling vertigo of different origins.

  11. Anodal tDCS to Right Dorsolateral Prefrontal Cortex Facilitates Performance for Novice Jazz Improvisers but Hinders Experts.

    Science.gov (United States)

    Rosen, David S; Erickson, Brian; Kim, Youngmoo E; Mirman, Daniel; Hamilton, Roy H; Kounios, John

    2016-01-01

    Research on creative cognition reveals a fundamental disagreement about the nature of creative thought, specifically, whether it is primarily based on automatic, associative (Type-1) or executive, controlled (Type-2) processes. We hypothesized that Type-1 and Type-2 processes make differential contributions to creative production that depend on domain expertise. We tested this hypothesis with jazz pianists whose expertise was indexed by the number of public performances given. Previous fMRI studies of musical improvisation have reported that domain expertise is characterized by deactivation of the right-dorsolateral prefrontal cortex (r-DLPFC), a brain area associated with Type-2 executive processing. We used anodal, cathodal, and sham transcranial direct current stimulation (tDCS) applied over r-DLPFC with the reference electrode on the contralateral mastoid (1.5 mA for 15 min, except for sham) to modulate the quality of the pianists' performances while they improvised over chords with drum and bass accompaniment. Jazz experts rated each improvisation for creativity, esthetic appeal, and technical proficiency. There was no main effect of anodal or cathodal stimulation on ratings compared to sham; however, a significant interaction between anodal tDCS and expertise emerged such that stimulation benefitted musicians with less experience but hindered those with more experience. We interpret these results as evidence for a dual-process model of creativity in which novices and experts differentially engage Type-1 and Type-2 processes during creative production.

  12. Anodal tDCS to right dorsolateral prefrontal cortex facilitates performance for novice jazz improvisers but hinders experts

    Directory of Open Access Journals (Sweden)

    David S Rosen

    2016-11-01

    Full Text Available Research on creative cognition reveals a fundamental disagreement about the nature of creative thought, specifically, whether it is primarily based on automatic, associative (Type-1 or executive, controlled (Type-2 processes. We hypothesized that Type-1 and Type-2 processes make differential contributions to creative production that depend on domain expertise. We tested this hypothesis with jazz pianists whose expertise was indexed by the number of public performances given. Previous fMRI studies of musical improvisation have reported that domain expertise is characterized by deactivation of the right-dorsolateral prefrontal cortex (r-DLPFC, a brain area associated with Type-2 executive processing. We used anodal, cathodal, and sham transcranial direct-current stimulation (tDCS applied over r-DLPFC with the reference electrode on the contralateral mastoid (1.5mA for 15 min., except for sham to modulate the quality of the pianists’ performances while they improvised over chords with drum and bass accompaniment. Jazz experts rated each improvisation for creativity, aesthetic appeal, and technical proficiency. There was no main effect of anodal or cathodal stimulation on ratings compared to sham; however, a significant interaction between anodal tDCS and expertise emerged such that stimulation benefitted musicians with less experience but hindered those with more experience. We interpret these results as evidence for a dual-process model of creativity in which novices and experts differentially engage Type-1 and Type-2 processes during creative production.

  13. Domain of the Gods: Do traditional beliefs hinder public acceptance of the human role in climate change?

    Science.gov (United States)

    Donner, S.

    2008-12-01

    Public acceptance of new scientific discoveries like natural selection, plate tectonics, or the human role in climate change naturally lags behind the pace of the discoveries. In the case of climate change, unease or outright rejection of the scientific evidence for the role of human activity in climate change has been a hindrance to mitigation and adaptation efforts. This skepticism is normally attributed to everything from the quality of science education, to disinformation campaigns by representatives of the coal and gas industry, to individual resistance to behavioral change, to the nature of the modern information culture. This skepticism of scientific evidence for climate change, though often inspired by politics, economics and the particular dynamics of climate change, may actually be rooted in ancient beliefs that the climate is beyond the influence of humans. In this presentation, I will outline how the notion that humans control or influence the weather runs contrary to thousands of years of belief in a separation between the earth - the domain of man - and sky - the domain of the gods. Evidence from religious history, traditional villages in the Pacific (Fjij and Kiribati) and from public discourse in North America all indicates that the millennia-old belief in an earth-sky separation hinders people's acceptance that human activity is affecting the climate. The human role in climate change therefore represents a substantial paradigm shift, similar to the role of natural selection in human evolution. These deep roots of climate change skepticism must be factored into public climate change education efforts.

  14. The Role of Organisational Phenomena in Software Cost Estimation: A Case Study of Supporting and Hindering Factors

    Directory of Open Access Journals (Sweden)

    Jurka Rahikkala

    2018-01-01

    Full Text Available Despite the fact that many researchers and practitioners agree that organisational issues are equally important as technical issues from the software cost estimation (SCE success point of view, most of the research focus has been put on the development of methods, whereas organisational factors have received surprisingly little academic scrutiny. This study aims to identify organisational factors that either support or hinder meaningful SCE, identifying their impact on estimation success. Top management’s role is specifically addressed. The study takes a qualitative and explorative case study based approach. In total, 18 semi-structured interviews aided the study of three projects in three organisations. Hence, the transferability of the results is limited. The results suggest that the role of the top management is important in creating prerequisites for meaningful estimation, but their day-to-day participation is not required for successful estimation. Top management may also induce undesired distortion in estimation. Estimation maturity and estimation success seem to have an interrelationship with software process maturity, but there seem to be no significant individual organisational factors, which alone would make estimation successful. Our results validate several distortions and biases reported in the previous studies, and show the SCE research focus has remained on methodologies and technical issues.

  15. Helping and hindering: perceptions of enablers and barriers to collaboration within a rural South Australian mental health network.

    Science.gov (United States)

    Crotty, Mikaila M; Henderson, Julie; Fuller, Jeffrey D

    2012-08-01

    To evaluate clinicians' perceptions of what helps and hinders the delivery of mental health care across a service network in a rural setting. Qualitative, semistructured interviews were conducted with 10 individuals who work in one rural mental health care service network. A regional centre in rural South Australia involving representatives of the mental health team, general practice, hospital, community health and nongovernment organisations. Clinicians' perceptions of barriers and enablers to working within their mental health care network were explored. Participants showed a strong shared commitment to effective mental health care delivery and a good understanding of the services that each offers. Interview data suggested that working relationships between local services could be perceived as stronger when a personal or historical element is recognisable. Similarly, the notion of familiarity and community involvement were perceived as facilitators in this network. A perceived barrier for participants was the failure to attract staff with mental health experience, leading to dependence upon the dedication and commitment of existing service providers. Collaboration is especially necessary in rural areas, where access to health care services is known to be difficult. The informality of relationships between service providers was shown to be the main facilitator in the network. This is both a strength as it promotes the communication between services and service providers that is essential for successful collaboration, yet is also a threat to the sustainability of the network based on the difficulties of staff recruitment and retention to rural settings. © 2012 The Authors. Australian Journal of Rural Health © National Rural Health Alliance Inc.

  16. Low voltage electric potential as a driving force to hinder biofouling in self-supporting carbon nanotube membranes.

    Science.gov (United States)

    Thamaraiselvan, Chidambaram; Ronen, Avner; Lerman, Sofia; Balaish, Moran; Ein-Eli, Yair; Dosoretz, Carlos G

    2017-11-03

    This study aimed at evaluating the contribution of low voltage electric field, both alternating (AC) and direct (DC) currents, on the prevention of bacterial attachment and cell inactivation to highly electrically conductive self-supporting carbon nanotubes (CNT) membranes at conditions which encourage biofilm formation. A mutant strain of Pseudomonas putida S12 was used a model bacterium and either capacitive or resistive electrical circuits and two flow regimes, flow-through and cross-flow filtration, were studied. Major emphasis was placed on AC due to its ability of repulsing and inactivating bacteria. AC voltage at 1.5 V, 1 kHz frequency and wave pulse above offset (+0.45) with 100Ω external resistance on the ground side prevented almost completely attachment of bacteria (>98.5%) with concomitant high inactivation (95.3 ± 2.5%) in flow-through regime. AC resulted more effective than DC, both in terms of biofouling reduction compared to cathodic DC and in terms of cell inactivation compared to anodic DC. Although similar trends were observed, a net reduced extent of prevention of bacterial attachment and inactivation was observed in filtration as compared to flow-through regime, which is mainly attributed to the permeate drag force, also supported by theoretical calculations in DC in capacitive mode. Electrochemical impedance spectroscopy analysis suggests a pure resistor behavior in resistance mode compared to involvement of redox reactions in capacitance mode, as source for bacteria detachment and inactivation. Although further optimization is required, electrically polarized CNT membranes offer a viable antibiofouling strategy to hinder biofouling and simplify membrane care during filtration. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Challenges That Hinder the Translation of Clinical Advances Into Practice: Results From an International Assessment in Colorectal Cancer.

    Science.gov (United States)

    Lazure, Patrice; Marshall, John L; Hayes, Sean M; Murray, Suzanne

    2016-03-01

    Over the past decade, individualization of treatment for colorectal cancer (CRC) has been improved by: (1) approval of several new agents by national agencies such as the US Food and Drug Administration (FDA); and (2) rapid advances in mutation analysis. However, data are sparse on the clinical challenges experienced by oncologists as they address the increased complexity created by the growing potential for individualization of CRC treatment. To identify clinical challenges experienced by oncologists regarding CRC treatment, an international assessment was conducted. A mixed methods approach was used, with the collection and analysis of qualitative (semistructured telephone interviews) and quantitative (online survey) data. Participants were oncologists actively practicing in 1 of 7 targeted countries with a minimum caseload of 10 CRC patients per year. The sample included 358 oncologists from China (n = 68), France (n = 44), Germany (n = 44), Italy (n = 45), Spain (n = 44), the United Kingdom (n = 45), and the United States (n = 68). Mixed methods findings indicated that oncologists' treatment selection is hindered by practice challenges in: (1) mutation analysis and subsequent adaptation of treatment; (2) optimal sequential use of treatment choices; (3) treatment individualization based on patient and tumor profile; (4) management of side effects and toxicities; (5) chemoresistance, cross-resistance, and combinations to overcome resistance; and (6) access to new emerging treatments. In the context of increased complexity created by the approval of new agents and advances in mutation analysis, challenges are experienced by practicing oncologists in the individualization of treatment for CRC patients. Details of these challenges should stimulate dialogue among oncologists, and development of interventions to improve clinical practice. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  18. Treatment with paracetamol, ketorolac or etoricoxib did not hinder alveolar bone healing: a histometric study in rats

    Directory of Open Access Journals (Sweden)

    Ricardo Nogueira Fracon

    2010-12-01

    Full Text Available Prostaglandins control osteoblastic and osteoclastic function under physiological or pathological conditions and are important modulators of the bone healing process. The non-steroidal anti-inflammatory drugs (NSAIDs inhibit cyclooxygenase (COX activity and consequently prostaglandins synthesis. Experimental and clinical evidence has indicated a risk for reparative bone formation related to the use of non-selective (COX-1 and COX-2 and COX-2 selective NSAIDs. Ketorolac is a non-selective NSAID which, at low doses, has a preferential COX-1 inhibitory effect and etoricoxib is a new selective COX-2 inhibitor. Although literature data have suggested that ketorolac can interfere negatively with long bone fracture healing, there seems to be no study associating etoricoxib with reparative bone formation. Paracetamol/acetaminophen, one of the first choices for pain control in clinical dentistry, has been considered a weak anti-inflammatory drug, although supposedly capable of inhibiting COX-2 activity in inflammatory sites. OBJECTIVE: The purpose of the present study was to investigate whether paracetamol, ketorolac and etoricoxib can hinder alveolar bone formation, taking the filling of rat extraction socket with newly formed bone as experimental model. MATERIAL AND METHODS: The degree of new bone formation inside the alveolar socket was estimated two weeks after tooth extraction by a differential point-counting method, using an optical microscopy with a digital camera for image capture and histometry software. Differences between groups were analyzed by ANOVA after confirming a normal distribution of sample data. RESULTS AND CONCLUSIONS: Histometric results confirmed that none of the tested drugs had a detrimental effect in the volume fraction of bone trabeculae formed inside the alveolar socket.

  19. Factors that hinder or enable maternal health strategies to reduce delays in rural and pastoralist areas in Ethiopia.

    Science.gov (United States)

    Jackson, Ruth; Tesfay, Fisaha Haile; Gebrehiwot, Tesfay Gebregzabher; Godefay, Hagos

    2017-02-01

    To document factors that hinder or enable strategies to reduce the first and second delays of the Three Delays in rural and pastoralist areas in Ethiopia. A key informant study was conducted with 44 Health Extension Workers in Afar Region, Kafa Zone (Southern Nation, Nationalities and Peoples' Region), and Adwa Woreda (Tigray Region). Health Extension Workers were trained to interview women and ask for stories about their recent experiences of birth. We interviewed the Health Extension Workers about their experiences referring women for Skilled Birth Attendance and Emergency Obstetric and Newborn Care. Data were analysed using thematic analysis. Themes related to reducing the first delay, such as the tradition of home birth, decision-making, distance and unavailability of transport, did not differ between the three locations. Themes related to reducing the second delay differed substantially. Health Extension Workers in Adwa Woreda were more likely to call ambulances due to support from the Health Development Army and a functioning referral system. In Kafa Zone, some Health Extension Workers were discouraged from calling ambulances as they were used for other purposes. In Afar Region, few Health Extension Workers were called to assist women as most women give birth at home with Traditional Birth Attendants unless they need to travel to health facilities for Emergency Obstetric and Newborn Care. Initiatives to reduce delays can improve access to maternal health services, especially when Health Extension Workers are supported by the Health Development Army and a functioning referral system, but district (woreda) health offices should ensure that ambulances are used as intended. © 2016 John Wiley & Sons Ltd.

  20. CO2 absorption and sequestration as various polymorphs of CaCO3 using sterically hindered amine.

    Science.gov (United States)

    Vinoba, Mari; Bhagiyalakshmi, Margandan; Grace, Andrews Nirmala; Chu, Dae Hyun; Nam, Sung Chan; Yoon, Yeoil; Yoon, Sung Ho; Jeong, Soon Kwan

    2013-12-17

    One aspect of the attempt to restrain global warming is the reduction of the levels of atmospheric CO2 produced by fossil fuel power systems. This study attempted to develop a method that reduces CO2 emissions by investigating the absorption of CO2 into sterically hindered amine 2-amino-2-methyl-1-propanol (AMP), the acceleration of the absorption rate by using the enzyme carbonic anhydrase (CA), and the conversion of the absorption product to stable carbonates. CO2 absorbed by AMP is converted via a zwitterion mechanism to bicarbonate species; the presence of these anions was confirmed with (1)H and (13)C NMR spectral analysis. The catalytic efficiency (kcat/Km), CO2 absorption capacities, and enthalpy changes (ΔHabs) of aqueous AMP in the presence or absence of CA were found to be 2.61 × 10(6) or 1.35 × 10(2) M(-1) s(-1), 0.97 or 0.96 mol/mol, and -69 or -67 kJ/mol, respectively. The carbonation of AMP-absorbed CO2 was performed by using various Ca(2+) sources, viz., CaCl2 (CAC), Ca(OOCCH3)2 (CAA), and Ca(OOCCH2CH3)2 (CAP), to obtain various polymorphs of CaCO3. The yields of CaCO3 from the Ca(2+) sources were found in the order CAP > CAA > CAC as a result of the effects of the corresponding anions. CAC produces pure rhombohedral calcite, and CAA and CAP produce the unusual phase transformation of calcite to spherical vaterite crystals. Thus, AMP in combination with CAA and CAP can be used as a CO2 absorbent and buffering agent for the sequestration of CO2 in porous CaCO3.

  1. Friend or Foe: Variability in How Sea Ice Can Both Hinder and Enhance Phytoplankton Blooms Across the Southern Ocean

    Science.gov (United States)

    Rohr, T.

    2016-02-01

    Globally, a suite of physical and biogeochemical controls govern the structure, size, and timing of seasonal phytoplankton blooms. In the Southern Ocean, the introduction of seasonal sea ice provides an additional constraining factor. From a bottom-up perspective, a reduction in sea ice can both enhance bloom development by permitting greater levels of surface PAR uninhibited by ice and suppress a bloom when reduced fresh melt-water inputs and increased vulnerability to wind stress combine to create deeper mixed layers and decrease depth integrated light availability. Regions along the Western Antarctic Peninsula have already seen a contradictory response to reduced ice cover, with enhanced summertime chlorophyll concentrations in the South, and large declines to the North. This dichotomy is thought to arise from differences in the interannual mean sea ice state, with extensively ice covered regions benefiting from reduced coverage and more sparsely covered regions hindered by further reductions. The questions arises: 1) At what threshold does a reduction in sea ice transition from amplifying blooms to suppressing them? 2) How do additional environmental considerations such as nutrient availability and trophic interactions complicate this transition? Here, we combine remote sensing observations and in-situ data (from PAL LTER) with a hierarchy of 1-D water column and global general circulation (CESM) models to access the variability in how regional differences in mean ice state combine with other environmental forcings to dictate how interannual variability (or long term trends) in ice coverage will affect bloom structure, size and dynamics. In doing so we will gain a better understanding of how predicted changes in sea ice will effect Southern Ocean productivity, which of course will have important consequences in the global carbon cycle and sustainability of healthy marine ecosystems.

  2. Casting a New Light on a Long Shadow: Saskatchewan Aboriginal High School Students Talk about What Helps and Hinders Their Learning

    Science.gov (United States)

    Stelmach, Bonnie; Kovach, Margaret; Steeves, Larry

    2017-01-01

    What do teachers do (or not do) that makes you want to go to school? A team of Saskatchewan researchers asked Saskatchewan Aboriginal high school students this question about the aspects of instructional practice that helps and hinders their learning. While responses pointed to several aspects, teacher relational instincts and capacities were the…

  3. Factors facilitating and hindering the intention to promote pulmonary rehabilitation for patients with COPD among respiratory therapists.

    Science.gov (United States)

    Chen, Yun-Ju; Fan, Jun-Yu; Guo, Su-Er; Hwang, Su-Lun; Yang, Tsung-Ming

    2017-01-01

    Pulmonary rehabilitation (PR) is recognized as the chief non-pharmacologic management approach for patients with COPD, but is clinically under-utilized. In Taiwan, respiratory therapists (RTs) are one of the first-line health care providers who spend vast amounts of time with COPD patients in PR programs. To better enhance patients' knowledge of and participation in PR, it is necessary to understand how PR is viewed by RTs, as well as how these views influence their behavioral intentions toward promoting PR. This study applied the Theory of Planned Behavior (TPB) to investigate both the behavioral intentions and the influential factors surrounding PR in RTs. This cross-sectional study used structured self-administered questionnaires at a national symposium for RTs to collect data on their knowledge, attitudes, subjective norms, perceived behavioral controls, and behavioral intentions with regard to promoting PR. Multiple linear regression analysis was used to identify significant factors affecting the intended promotion of PR by RTs. The response rate after excluding respondents with incomplete data was 88.1% (n=379). A majority of the participants were college graduates, aged over 30 years, and women. The respective percentage scores derived from questionnaires gauging the knowledge, attitudes, subjective norms, self-efficacy, and behavioral intentions components of total PR scores were 63.12%, 71.33%, 68.96%, 66.46%, and 80.29%. The factors significantly affecting RTs' intentions to suggest PR participation to COPD patients or encourage it were attitudes, subjective norms, and self-efficacy. The total model explained 22.5% of the variance in behavioral intentions. The results of the study suggest that RTs strongly intend to promote PR, but are hindered by insufficient knowledge, attitudes, and self-efficacy with regard to it. Applying TPB provided insight into which factors can be addressed, and by whom. For example, enhancing RTs' self-efficacy can be achieved

  4. Autoreactivity and exceptional CDR plasticity (but not unusual polyspecificity hinder elicitation of the anti-HIV antibody 4E10.

    Directory of Open Access Journals (Sweden)

    Kathryn A K Finton

    Full Text Available The broadly-neutralizing anti-HIV antibody 4E10 recognizes an epitope in the membrane-proximal external region of the HIV envelope protein gp41. Previous attempts to elicit 4E10 by vaccination with envelope-derived or reverse-engineered immunogens have failed. It was presumed that the ontogeny of 4E10-equivalent responses was blocked by inherent autoreactivity and exceptional polyreactivity. We generated 4E10 heavy-chain knock-in mice, which displayed significant B cell dysregulation, consistent with recognition of autoantigen/s by 4E10 and the presumption that tolerance mechanisms may hinder the elicitation of 4E10 or 4E10-equivalent responses. Previously proposed candidate 4E10 autoantigens include the mitochondrial lipid cardiolipin and a nuclear splicing factor, 3B3. However, using carefully-controlled assays, 4E10 bound only weakly to cardiolipin-containing liposomes, but also bound negatively-charged, non-cardiolipin-containing liposomes comparably poorly. 4E10/liposome binding was predominantly mediated by electrostatic interactions rather than presumed hydrophobic interactions. The crystal structure of 4E10 free of bound ligands showed a dramatic restructuring of the combining site, occluding the HIV epitope binding site and revealing profound flexibility, but creating an electropositive pocket consistent with non-specific binding of phospholipid headgroups. These results strongly suggested that antigens other than cardiolipin mediate 4E10 autoreactivity. Using a synthetic peptide library spanning the human proteome, we determined that 4E10 displays limited and focused, but unexceptional, polyspecificity. We also identified a novel autoepitope shared by three ER-resident inositol trisphosphate receptors, validated through binding studies and immunohistochemistry. Tissue staining with 4E10 demonstrated reactivity consistent with the type 1 inositol trisphosphate receptor as the most likely candidate autoantigen, but is inconsistent with

  5. Common attributes in retired professional cricketers that may enhance or hinder quality of life after retirement: a qualitative study.

    Science.gov (United States)

    Filbay, Stephanie R; Bishop, Felicity; Peirce, Nicholas; Jones, Mary E; Arden, Nigel K

    2017-07-26

    Retired professional cricketers shared unique experiences and may possess specific psychological attributes with potential to influence quality of life (QOL). Additionally, pain and osteoarthritis can be common in retired athletes which may negatively impact QOL. However, QOL in retired athletes is poorly understood. This study explores the following questions from the personal perspective of retired cricketers: How do retired cricketers perceive and experience musculoskeletal pain and function in daily life? Are there any psychological attributes that might enhance or hinder retired cricketers' QOL? A qualitative study using semistructured interviews, which were subject to inductive, thematic analysis. A data-driven, iterative approach to data coding was employed. All participants had lived and played professional cricket in the UK and were living in the UK or abroad at the time of interview. Eighteen male participants, aged a mean 57±11 (range 34-77) years had played professional cricket for a mean 12±7 seasons and had been retired from professional cricket on average 23±9 years. Fifteen participants reported pain or joint difficulties and all but one was satisfied with their QOL. Most retired cricketers reflected on experiences during their cricket career that may be associated with the psychological attributes that these individuals shared, including resilience and a positive attitude. Additional attributes included a high sense of body awareness, an ability to self-manage pain and adapt lifestyle choices to accommodate physical limitations. Participants felt fortunate and proud to have played professional cricket, which may have further contributed to the high QOL in this group of retired cricketers. Most retired cricketers in this study were living with pain or joint difficulties. Despite this, all but one was satisfied or very satisfied with their QOL. This may be partly explained by the positive psychological attributes that these retired cricketers

  6. Factors facilitating and hindering the intention to promote pulmonary rehabilitation for patients with COPD among respiratory therapists

    Directory of Open Access Journals (Sweden)

    Chen YJ

    2017-09-01

    knowledge, attitudes, subjective norms, self-efficacy, and behavioral intentions components of total PR scores were 63.12%, 71.33%, 68.96%, 66.46%, and 80.29%. The factors significantly affecting RTs’ intentions to suggest PR participation to COPD patients or encourage it were attitudes, subjective norms, and self-efficacy. The total model explained 22.5% of the variance in behavioral intentions.Conclusion: The results of the study suggest that RTs strongly intend to promote PR, but are hindered by insufficient knowledge, attitudes, and self-efficacy with regard to it. Applying TPB provided insight into which factors can be addressed, and by whom. For example, enhancing RTs’ self-efficacy can be achieved through PR training via school curricula, further regular continuing education and/or courses, and practical experience. Keywords: behavioral intention, theory of planned behavior, exercise program, self-efficacy, respiratory therapist, COPD

  7. Determination of a Polymeric Hindered Amine Light Stabilizer in Polypropylene Formulated with Magnesium Hydroxide Flame Retardant by Reactive Thermal Desorption-Gas Chromatography

    OpenAIRE

    Yoshihiko, Taguchi; Yasuyuki, Ishida; Hajime, Ohtani; Hiroyuki, Bekku; Masaya, Sera

    2004-01-01

    A polymeric hindered amine light stabilizer (HALS), Tinuvin 622 (MW = 4000), in PP materials formulated with a magnesium hydroxide flame retardant was determined by reactive thermal desorption (RTD) gas chromatography (GC). Two kinds of the HALS components that were formed through the RTD in the presence of tetramethylammonium hydroxide [(CH3)4NOH, TMAH] were clearly observed in the chromatograms of the PP samples, with negligible interference from the other additives and the PP substrate. He...

  8. Dye stability and performances of dye-sensitized solar cells with different nitrogen additives at elevated temperatures - Can sterically hindered pyridines prevent dye degradation?

    Energy Technology Data Exchange (ETDEWEB)

    Tuyet Nguyen, Phuong; Lund, Torben [Department of Science, Systems and Models, Roskilde University, 4000 Roskilde (Denmark); Rand Andersen, Anders [University of Southern Denmark, Institute of Sensors, Signals and Electrotechnics (SENSE), Niels Bohrs Alle 1, 5230 Odense M (Denmark); Danish Technological Institute, Plastics Technology, Gregersensvej 2630 Taastrup (Denmark); Morten Skou, Eivind [University of Southern Denmark, Department of Chemical Engineering, Biotechnology and Enviromental Technology, Niels Bohrs Alle 1, 5230 Odense M (Denmark)

    2010-10-15

    The homogeneous kinetics of the nucleophilic substitution reactions between the ruthenium dye N719 and eight pyridines and 1-methylbenzimidazole have been investigated in 3-methoxypropionitrile at 100 C. The half lives of N719 with the additives 4-tert-butylpyridine (0.5 M) and 1-methylbenzimidazole (0.5 M) were 57 and 160 h, respectively. Sterically hindered pyridines like 2,6-lutidine did not react with N719. The efficiencies of dye-sensitized solar cells (DSC, area=8.0 cm{sup 2}) prepared with 1-methylbenzimidazole (MBI), 4-tert-butylpyridine (4-TBP), 2,6-lutidine and without any additive were 7.1%, 6.2%, 6.0% and 4.8%, respectively. The cells were stored in dark at 85 C and their I-V curves and impedance spectra were measured at regular time intervals. The N719 dye degradation in the cells were monitored by a new dye extraction protocol combined with analysis of the dye extract by HPLC coupled to mass spectrometry. After 300 h storage in dark at 85 C 40% of the initial amount of N719 dye was degraded in DSC cells prepared with MBI and the efficiency was decreased to 40% of its initial value. DSC cells prepared with 2,6-lutidine or no additives showed smaller thermal dye and efficiency stability at elevated temperatures than DSC cells prepared with the none sterically hindered additives MBI and 4-TBP. In the cells prepared with 2,6-lutidine or no additive higher contents of the iodo products [RuL{sub 2}(NCS)(iodide)]{sup +} and [RuL{sub 2}(3-MPN)(iodide)]{sup +} were found than in cells prepared with 4-TBP and MBI. It is suggested that sterically hindered pyridines have smaller complexation constants with I{sub 3}{sup -} than unsterically hindered additives. This may explain the observed faster nucleophilic substitution rates of uncomplexed I{sub 3}{sup -} with N719 in DSC cells prepared with sterically hindered pyridines. The EIS analysis showed that the lifetime of the injected electrons in the TiO{sub 2}{tau}{sub eff} is reduced by a thermally induced change

  9. Optimising Translational Research Opportunities: A Systematic Review and Narrative Synthesis of Basic and Clinician Scientists' Perspectives of Factors Which Enable or Hinder Translational Research.

    Science.gov (United States)

    Fudge, Nina; Sadler, Euan; Fisher, Helen R; Maher, John; Wolfe, Charles D A; McKevitt, Christopher

    2016-01-01

    Translational research is central to international health policy, research and funding initiatives. Despite increasing use of the term, the translation of basic science discoveries into clinical practice is not straightforward. This systematic search and narrative synthesis aimed to examine factors enabling or hindering translational research from the perspective of basic and clinician scientists, a key stakeholder group in translational research, and to draw policy-relevant implications for organisations seeking to optimise translational research opportunities. We searched SCOPUS and Web of Science from inception until April 2015 for papers reporting scientists' views of the factors they perceive as enabling or hindering the conduct of translational research. We screened 8,295 papers from electronic database searches and 20 papers from hand searches and citation tracking, identifying 26 studies of qualitative, quantitative or mixed method designs. We used a narrative synthesis approach and identified the following themes: 1) differing concepts of translational research 2) research processes as a barrier to translational research; 3) perceived cultural divide between research and clinical care; 4) interdisciplinary collaboration as enabling translation research, but dependent on the quality of prior and current social relationships; 5) translational research as entrepreneurial science. Across all five themes, factors enabling or hindering translational research were largely shaped by wider social, organisational, and structural factors. To optimise translational research, policy could consider refining translational research models to better reflect scientists' experiences, fostering greater collaboration and buy in from all types of scientists. Organisations could foster cultural change, ensuring that organisational practices and systems keep pace with the change in knowledge production brought about by the translational research agenda.

  10. Optimising Translational Research Opportunities: A Systematic Review and Narrative Synthesis of Basic and Clinician Scientists' Perspectives of Factors Which Enable or Hinder Translational Research.

    Directory of Open Access Journals (Sweden)

    Nina Fudge

    Full Text Available Translational research is central to international health policy, research and funding initiatives. Despite increasing use of the term, the translation of basic science discoveries into clinical practice is not straightforward. This systematic search and narrative synthesis aimed to examine factors enabling or hindering translational research from the perspective of basic and clinician scientists, a key stakeholder group in translational research, and to draw policy-relevant implications for organisations seeking to optimise translational research opportunities.We searched SCOPUS and Web of Science from inception until April 2015 for papers reporting scientists' views of the factors they perceive as enabling or hindering the conduct of translational research. We screened 8,295 papers from electronic database searches and 20 papers from hand searches and citation tracking, identifying 26 studies of qualitative, quantitative or mixed method designs. We used a narrative synthesis approach and identified the following themes: 1 differing concepts of translational research 2 research processes as a barrier to translational research; 3 perceived cultural divide between research and clinical care; 4 interdisciplinary collaboration as enabling translation research, but dependent on the quality of prior and current social relationships; 5 translational research as entrepreneurial science. Across all five themes, factors enabling or hindering translational research were largely shaped by wider social, organisational, and structural factors.To optimise translational research, policy could consider refining translational research models to better reflect scientists' experiences, fostering greater collaboration and buy in from all types of scientists. Organisations could foster cultural change, ensuring that organisational practices and systems keep pace with the change in knowledge production brought about by the translational research agenda.

  11. Direct determination of a polymeric hindered amine light stabilizer in polypropylene by thermal desorption-gas chromatography assisted by in-line chemical reaction

    OpenAIRE

    Keiichiro, Kimura; Toshio, Yoshikawa; Yoshihiko, Taguchi; Yasuyuki, Ishida; Hajime, Ohtani; Shin, Tsuge

    2000-01-01

    A method to determine a polymeric hindered amine light stabilizer (HALS), Adekastab LA-68LD, in polypropylene (PP) was developed on the basis of reactive thermal desorption-gas chromatography (RTD-GC) in the presence of an organic alkali, tetramethylammonium hydroxide [(CH3)4NOH, TMAH]. RTD-GC using 25% TMAH methanol solution allowed the sensitive determination of HALS in PP as methylated fragments on the resulting chromatogram with a 4.8% relative standard deviation without the need for an...

  12. Ett kvinnligt sätt att leda : En studie om hur kvinnliga mellanchefer i ett mansdominerat bolag upplever hinder och möjligheter

    OpenAIRE

    Skotte, Ida; Andersson, Jenny

    2009-01-01

    I denna studie analyserar vi kvinnligt ledarskap i en mansdominerad bransch. Genom åtta kvalitativa intervjuer undersöker vi vilka gemensamma egenskaper, strategier samt hinder och möjligheter kvinnliga mellanchefer upplever i sin ledarroll. Vår teoretiska referensram tar utgångspunkt i Hirdmans genussystemteori, vilken bidrar till att förklara hur kvinnlighet och manlighet skapas, samt aspekter kring det maktförhållande som råder mellan kvinnor och män. I den teoretiska referensramen tar vi ...

  13. The Attitude of Math Teachers toward Cooperative Learning and Institutional Elements that May Help or Hinder its Use as a Teaching Methodology

    Directory of Open Access Journals (Sweden)

    Luis Gerardo Meza-Cascante

    2015-01-01

    Full Text Available This paper presents the results of research conducted in high schools in the central region of the Cartago province, Costa Rica. The goal of the research was to determine the attitude of high school math teachers toward cooperative learning in math and identify factors in secondary education institutions that can help or hinder the implementation of cooperative learning as a strategy for teaching mathematics. The research was conducted with 39 secondary education math teachers, who participated in a workshop on cooperative learning in mathematics. The attitude toward this methodology was measured by using semantic differential. This information was triangulated with data obtained from non-participant observation. A combination of in-depth interviews and non-participant observation was used to access data that identifies institutional factors helping or hindering the implementation of math cooperative learning. Findings suggest a positive attitude from teachers toward integrating cooperative work as a teaching strategy to promote math learning and toward the role played by school principals in the adoption of educational innovations. It also reveals that high schools have adequate material conditions to implement the methodology, although the need for training is considered. This finding should be taken into account by the proponents of this methodological option.

  14. Oceanographic station data from bottle casts from the WEST-HINDER and other platforms from multiple Ocean Weather Station (OWS) in the North Atlantic Ocean 02 March 1958 to 24 March 1971 (NODC Accession 7101039)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Oceanographic station data were collected from the WEST-HINDER and other platforms within a 1-mile radius of Ocean Weather Station A (6200N 03300W), B (5630N...

  15. Highly efficient aerobic oxidation of alcohols by using less-hindered nitroxyl-radical/copper catalysis: optimum catalyst combinations and their substrate scope.

    Science.gov (United States)

    Sasano, Yusuke; Kogure, Naoki; Nishiyama, Tomohiro; Nagasawa, Shota; Iwabuchi, Yoshiharu

    2015-04-01

    The oxidation of alcohols into their corresponding carbonyl compounds is one of the most fundamental transformations in organic chemistry. In our recent report, 2-azaadamantane N-oxyl (AZADO)/copper catalysis promoted the highly chemoselective aerobic oxidation of unprotected amino alcohols into amino carbonyl compounds. Herein, we investigated the extension of the promising AZADO/copper-catalyzed aerobic oxidation of alcohols to other types of alcohol. During close optimization of the reaction conditions by using various alcohols, we found that the optimum combination of nitroxyl radical, copper salt, and solution concentration was dependent on the type of substrate. Various alcohols, including highly hindered and heteroatom-rich ones, were efficiently oxidized into their corresponding carbonyl compounds under mild conditions with lower amounts of the catalysts. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Septin 7 reduces nonmuscle myosin IIA activity in the SNAP23 complex and hinders GLUT4 storage vesicle docking and fusion

    Energy Technology Data Exchange (ETDEWEB)

    Wasik, Anita A.; Dumont, Vincent [Department of Pathology, University of Helsinki, 00014 Helsinki (Finland); Tienari, Jukka [Department of Pathology, University of Helsinki and Helsinki University Hospital, 00290 Helsinki, 05850 Hyvinkää (Finland); Nyman, Tuula A. [Institute of Biotechnology, University of Helsinki, 00014 Helsinki (Finland); Fogarty, Christopher L.; Forsblom, Carol; Lehto, Markku [Folkhälsan Institute of Genetics, Folkhälsan Research Center, 00290 Helsinki (Finland); Abdominal Center Nephrology, University of Helsinki and Helsinki University Hospital, 000290 Helsinki (Finland); Diabetes& Obesity Research Program, Research Program´s Unit, 00014 University of Helsinki (Finland); Lehtonen, Eero [Department of Pathology, University of Helsinki, 00014 Helsinki (Finland); Laboratory Animal Centre, University of Helsinki, 00014 Helsinki (Finland); Groop, Per-Henrik [Folkhälsan Institute of Genetics, Folkhälsan Research Center, 00290 Helsinki (Finland); Abdominal Center Nephrology, University of Helsinki and Helsinki University Hospital, 000290 Helsinki (Finland); Diabetes& Obesity Research Program, Research Program´s Unit, 00014 University of Helsinki (Finland); Baker IDI Heart & Diabetes Institute, 3004 Melbourne (Australia); Lehtonen, Sanna, E-mail: sanna.h.lehtonen@helsinki.fi [Department of Pathology, University of Helsinki, 00014 Helsinki (Finland)

    2017-01-15

    Glomerular epithelial cells, podocytes, are insulin responsive and can develop insulin resistance. Here, we demonstrate that the small GTPase septin 7 forms a complex with nonmuscle myosin heavy chain IIA (NMHC-IIA; encoded by MYH9), a component of the nonmuscle myosin IIA (NM-IIA) hexameric complex. We observed that knockdown of NMHC-IIA decreases insulin-stimulated glucose uptake into podocytes. Both septin 7 and NM-IIA associate with SNAP23, a SNARE protein involved in GLUT4 storage vesicle (GSV) docking and fusion with the plasma membrane. We observed that insulin decreases the level of septin 7 and increases the activity of NM-IIA in the SNAP23 complex, as visualized by increased phosphorylation of myosin regulatory light chain. Also knockdown of septin 7 increases the activity of NM-IIA in the complex. The activity of NM-IIA is increased in diabetic rat glomeruli and cultured human podocytes exposed to macroalbuminuric sera from patients with type 1 diabetes. Collectively, the data suggest that the activity of NM-IIA in the SNAP23 complex plays a key role in insulin-stimulated glucose uptake into podocytes. Furthermore, we observed that septin 7 reduces the activity of NM-IIA in the SNAP23 complex and thereby hinders GSV docking and fusion with the plasma membrane. - Highlights: • Septin 7, nonmuscle myosin heavy chain IIA (NMHC-IIA) and SNAP23 form a complex. • Knockdown of septin 7 increases NM-IIA activity in the SNAP23 complex. • Insulin decreases septin 7 level and increases NM-IIA activity in the SNAP23 complex. • Septin 7 hinders GSV docking/fusion by reducing NM-IIA activity in the SNAP23 complex.

  17. Impact of Weak Agostic Interactions in Nickel Electrocatalysts for Hydrogen Oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Klug, Christina M. [Center for Molecular Electrocatalysis, Pacific Northwest National Laboratory, P.O. Box 999, K2-57, Richland, Washington 99352, United States; O’Hagan, Molly [Center for Molecular Electrocatalysis, Pacific Northwest National Laboratory, P.O. Box 999, K2-57, Richland, Washington 99352, United States; Bullock, R. Morris [Center for Molecular Electrocatalysis, Pacific Northwest National Laboratory, P.O. Box 999, K2-57, Richland, Washington 99352, United States; Appel, Aaron M. [Center for Molecular Electrocatalysis, Pacific Northwest National Laboratory, P.O. Box 999, K2-57, Richland, Washington 99352, United States; Wiedner, Eric S. [Center for Molecular Electrocatalysis, Pacific Northwest National Laboratory, P.O. Box 999, K2-57, Richland, Washington 99352, United States

    2017-06-08

    To understand how H2 binding and oxidation is influenced by [Ni(PR2NR'2)2]2+ PR2NR'2 catalysts with H2 binding energies close to thermoneutral, two [Ni(PPh2NR'2)2]2+ (R = Me or C14H29) complexes with phenyl substituents on phosphorous and varying alkyl chain lengths on the pendant amine were studied. In the solid state, [Ni(PPh2NMe2)2]2+ exhibits an anagostic interaction between the Ni(II) center and the α-CH3 of the pendant amine, and DFT and variable-temperature 31P NMR experiments suggest than the anagostic interaction persists in solution. The equilibrium constants for H2 addition to these complexes was measured by 31P NMR spectroscopy, affording free energies of H2 addition (ΔG°H2) of –0.8 kcal mol–1 in benzonitrile and –1.6 to –2.3 kcal mol–1 in THF. The anagostic interaction contributes to the low driving force for H2 binding by stabilizing the four-coordinate Ni(II) species prior to binding of H2. The pseudo-first order rate constants for H2 addition at 1 atm were measured by variable scan rate cyclic voltammetry, and were found to be similar for both complexes, less than 0.2 s–1 in benzonitrile and 3 –6 s–1 in THF. In the presence of exogenous base and H2 , turnover frequencies of electrocatalytic H2 oxidation were measured to be less than 0.2 s–1 in benzonitrile and 4 –9 s–1 in THF. These complexes are slower electrocatalysts for H2 oxidation than previously studied [Ni(PR2NR'2)2]2+ complexes due to a competition between H2 binding and formation of the anagostic interaction. However, the decrease in catalytic rate is accompanied by a beneficial 130 mV decrease in overpotential. This research was supported as part of the Center for Molecular Electrocatalysis, an Energy Frontier Research Center funded by the U.S. Department of Energy (DOE), Office of Science, Office of Basic Energy Sciences. Computational resources were provided at the National Energy Research Scientific Computing Center (NERSC) at Lawrence Berkeley National Laboratory. Mass spectrometry experiments were performed in the William R. Wiley Environmental Molecular Sciences Laboratory, a DOE national scientific user facility sponsored by the DOE’s Office of Biological and Environmental Research and located and the Pacific Northwest National Laboratory (PNNL). The authors thank Dr. Rosalie Chu for mass spectroscopy analysis. PNNL is operated by Battelle for DOE.

  18. Simulating the Agostic Interaction in Electron-deficient (16-e) Group ...

    African Journals Online (AJOL)

    NICO

    tion exist or not is the structure of the complex. The distance that separates the hydrogen atom and the metal is in the range of. 1.8–2.3 Å, while the M-H-C angle is in the range 90–140°. With recent advances in the computational chemistry theoretical methods have became powerful tools in characterizing such interactions.

  19. Facilitating or hindering social cohesion?

    African Journals Online (AJOL)

    feelings of solidarity in black communities. The transition to .... young people and keep them occupied with sports… As you can see across the field, we have so many unemployed boys gambling and getting high on drugs. It is these people that .... February 2016). 10 Malose Langa, Adolescent boys talk about absent fathers,.

  20. Hindered Diphenoquinones: Diradicals of Oxygen

    Energy Technology Data Exchange (ETDEWEB)

    Bourdon, Jean; Calvin, Melvin

    1956-07-10

    Attempts were made to prepare a diphenoquinone having substituents in 2,2'-positions in order to prevent the planarity of the molecule and get a diradical of oxygen. The 2,2'-dimethyl-5,5'-di-t-butyldiphenoquinone was prepared and was shown to be in equilibrium with a small amount of diradical. This compound slowly polymerizes.

  1. HINDERED DIFFUSION OF COAL LIQUIDS

    Energy Technology Data Exchange (ETDEWEB)

    Theodore T. Tsotsis; Muhammad Sahimi; Ian A. Webster

    1996-01-01

    It was the purpose of the project described here to carry out careful and detailed investigations of petroleum and coal asphaltene transport through model porous systems under a broad range of temperature conditions. The experimental studies were to be coupled with detailed, in-depth statistical and molecular dynamics models intended to provide a fundamental understanding of the overall transport mechanisms and a more accurate concept of the asphaltene structure. The following discussion describes some of our accomplishments.

  2. Personal interests hinder Rail Baltica

    Index Scriptorium Estoniae

    2011-01-01

    Läti seimi liige Janis Reirs leiab, et Rail Baltica ehitus on Moskva ja Riia vahelise raudtee ehitusest prioriteetsem, kuna esimest võib potentsiaalselt finantseerida Euroopa Liit. Transpordiminister Uldis Augulis kohtub oma Venemaa kolleegi Igor Levitiniga 7. aprillil. Peaminister Valdis Dombrovskise sõnul vajavad mõlemad projektid majandusanalüüsi

  3. Facilitating or hindering social cohesion?

    African Journals Online (AJOL)

    This article discusses the contribution of the Community Work Programme (CWP) to social cohesion, a ... employment safety net to unemployed people in order ... CWP taught us. We can work together with the community.24. It was evident in the six communities that networks between people increased as a result of the.

  4. Photodegradation of sugarcane bagasse fibers: influence of acetylation or grafting UV-absorber and/or hindered nitroxide radical on their photostability

    Energy Technology Data Exchange (ETDEWEB)

    Ruggiero, Reinaldo; Machado, Antonio E.H. [Universidade Federal de Uberlandia, MG (Brazil). Lab. de Fotoquimica e Quumica de Lignocelulosicos]. E-mail: reinaldo@ufu.br; Hoareau, William; Gardrat, Christian; Nourmamode, Aziz; Grelier, Stephane; Castellan, Alain [Universite Bordeaux 1, Talence (France). Lab. de Chimie des Substances Vegetales]. E-mail: a.castellan@lcsv.u-bordeaux1.fr

    2006-08-15

    Unbleached (SCB) and peroxide bleached (PB-SCB) sugarcane bagasse fibers were grafted with hydroxyphenyl benzotriazole UV absorber (1) and/or hindered nitroxide radical of piperidinyloxy type (3). PB-SCB fibers were also acetylated with acetic anhydride. The photosensitivity of the various fibers to UV light was comparatively evaluated using Lab color coordinates and by monitoring their UV-Visible diffuse reflectance spectra. SCB fibers were found to be photostable whereas PB-SCB fibers presented some sensitivity to UV light. The stability of SCB fibers was attributed to the presence of photostable para-hydroxy phenylpropane units in SCB lignin. The grafted and non-grafted SCB fibers showed similar behaviors against UV-Visible light whereas grafted PB-SCB were photostabilized by the presence of 2 or 4 or both. Acetylation of PB-SCB fibers induced photostabilization in addition to some photobleaching effect. The photobleaching was also revealed by fluorescence emission studies. As a consequence of these observations, SCB fibers might be considered to have a high potential for lignocellulosic materials to be used outdoors. (author)

  5. A new six-dimensional potential energy surface for H2-N2O and its adiabatic-hindered-rotor treatment

    Science.gov (United States)

    Wang, Lecheng; Xie, Daiqian; Le Roy, Robert J.; Roy, Pierre-Nicholas

    2013-07-01

    A six-dimensional ab initio potential energy surface (PES) for H2-N2O which explicitly includes the symmetric and asymmetric vibrational coordinates Q1 and Q3 of N2O is calculated at the coupled-cluster singles and doubles with noniterative inclusion of connected triple level using an augmented correlation-consistent polarized-valence quadruple-zeta basis set together with midpoint bond functions. Four-dimensional intermolecular PESs are then obtained by fitting the vibrationally averaged interactions energies for υ3(N2O) = 0 and 1 to the Morse/long-range analytical form. In the fits, fixing the long-range parameters at theoretical values smoothes over the numerical noise in the ab initio points in the long-range region of the potential. Using the adiabatic hindered-rotor approximation, two-dimensional PESs for hydrogen-N2O complexes with different isotopomers of hydrogen are generated by averaging the 4D PES over the rotation of the hydrogen molecule within the complex. The band-origin shifts for the hydrogen-N2O dimers calculated using both the 4D PESs and the angle-averaged 2D PESs are all in good agreement with each other and with the available experimental observations. The predicted infrared transition frequencies for para-H2-N2O and ortho-D2-N2O are also consistent with the observed spectra.

  6. Sterically hindered C(alpha, alpha)-disubstituted alpha-amino acids: synthesis from alpha-nitroacetate and incorporation into peptides.

    Science.gov (United States)

    Fu, Y; Hammarström, L G; Miller, T J; Fronczek, F R; McLaughlin, M L; Hammer, R P

    2001-10-19

    The preparation of sterically hindered and polyfunctional C(alpha,alpha)-disubstituted alpha-amino acids (alpha alpha AAs) via alkylation of ethyl nitroacetate and transformation into derivatives ready for incorporation into peptides are described. Treatment of ethyl nitroacetate with N,N-diisopropylethylamine (DIEA) in the presence of a catalytic amount of tetraalkylammonium salt, followed by the addition of an activated alkyl halide or Michael acceptor, gives the doubly C-alkylated product in good to excellent yields. Selective nitro reduction with Zn in acetic acid or hydrogen over Raney Ni gives the corresponding amino ester that, upon saponification, can be protected with the fluorenylmethyloxycarbonyl (Fmoc) group. The first synthesis of an orthogonally protected, tetrafunctional C(alpha,alpha)-disubstituted analogue of aspartic acid, 2,2-bis(tert-butylcarboxymethyl)glycine (Bcmg), is described. Also, the sterically demanding C(alpha,alpha)-dibenzylglycine (Dbg) has been incorporated into a peptide using solid-phase synthesis. It was found that once sterically congested Dbg is at the peptide N-terminus, further chain extension becomes very difficult using uronium or phosphonium salts (PyAOP, PyAOP/HOAt, HATU). However, preformed amino acid symmetrical anhydride couples to N-terminal Dbg in almost quantitative yield in nonpolar solvent (dichloroethane-DMF, 9:1).

  7. Hindered rotational energy barriers of BH4- tetrahedra in β-Mg(BH4)2 from quasielastic neutron scattering and DFT calculations

    DEFF Research Database (Denmark)

    Blanchard, Didier; Maronsson, Jon Bergmann; Riktor, M.D.

    2012-01-01

    In this work, hindered rotations of the BH4- tetrahedra in Mg(BH4)2 were studied by quasielastic neutron scattering, using two instruments with different energy resolution, in combination with density functional theory (DFT) calculations. Two thermally activated reorientations of the BH4- units......, around the 2-fold (C2) and 3-fold (C3) axes were observed at temperatures from 120 to 440 K. The experimentally obtained activation energies (EaC2 = 39 and 76 meV and EaC3 = 214 meV) and mean residence times between reorientational jumps are comparable with the energy barriers obtained from DFT...... calculations. A linear dependency of the energy barriers for rotations around the C2 axis parallel to the Mg-Mg axis with the distance between these two axes was revealed by the DFT calculations. At the lowest temperature (120 K) only 15% of the BH4- units undergo rotational motion and from comparison with DFT...

  8. Bassiouney Reem (ed., Arabic and the media. Linguistic analyses and applications, Brill, Leiden-Boston, 2010 in T. Muraoka, C. H. M. Versteegh, A. D. Rubin (eds., Studies in Semitic languages and linguistics, vol. 57, 303 p.

    Directory of Open Access Journals (Sweden)

    Myriam Achour Kallel

    2011-11-01

    Full Text Available Arabic and the Media est le volume 57 de la série « Studies in Semitic Languages and Linguistics » publié chez Brill. L’ouvrage est divisé en trois parties : « Newspaper language », « Arabic variation and the media » et « Applications : approaching media in the classroom ». Le volume se termine par une liste de présentation des auteurs et un index des mots clés. Les quatorze contributions viennent en majorité de spécialistes en linguistique et/ou en langue arabe. Les terrains les plus représe...

  9. Effects of a hindered amine light stabilizer and a UV light absorber used in maxillofacial elastomers on human gingival epithelial cells and fibroblasts.

    Science.gov (United States)

    Tipton, David A; Lewis, J West

    2008-09-01

    Ultraviolet light absorber (UVA) and hindered amine light stabilizer (HALS) retard sun-induced pigment degradation in silicone elastomeric maxillofacial prostheses. HALS inhibits polymer degradation and UVA dissipates UV radiation. Their effects on oral cells are unknown. The purpose of this study was to evaluate the effects of UVA and HALS on membrane integrity, viability, and proliferation of human gingival fibroblasts and epithelial cells. Tinuvin 123 (HALS) and Tinuvin 213 (UVA) were assessed for cytotoxicity, individually and in a 1:1 ratio (used in elastomers; HALS/UVA). The cells were exposed to HALS, UVA, or HALS/UVA (or control media containing only the diluent), and colorimetric assays measured membrane damage, viability, and proliferation. The data (% cytotoxicity or % control) were analyzed using 3-way cross-classified fixed effects ANOVA (alpha=.05). HALS did not negatively affect either cell type. UVA or HALS/UVA (>or= approximately 0.004%) decreased viability by >or=90% in both cell lines; lower concentrations decreased activity in epithelial cells while increasing it in fibroblasts. UVA or HALS/UVA damaged membranes of both cell lines, but epithelial cells were more resistant. UVA or HALS/UVA inhibited proliferation of both cell types similarly. There was a slight synergistic effect of HALS and UVA on membrane damage in both cell lines, but generally not on other parameters. Although it is unknown if HALS or UVA leaches from silicone elastomers in vivo, these data suggest that relative resistance of epithelial cells to UVA-induced membrane damage, and UVA's stimulation of fibroblast viability at some concentrations, might provide some protective effect.

  10. Quantitative analysis of an oligomeric hindered amine light stabilizer in polypropylene by matrix-assisted laser desorption/ionization mass spectrometry using a solid sampling technique.

    Science.gov (United States)

    Taguchi, Yoshihiko; Ishida, Yasuyuki; Matsubara, Hideki; Ohtani, Hajime

    2006-01-01

    A small amount of an oligomeric hindered amine light stabilizer (HALS) (Adekastab LA-68LD) in polypropylene (PP) materials was directly determined by solid sampling matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) using an internal standard method. First the matrix reagent (dithranol), 20 mg, and the empirically selected internal standard, angiotensin I (MW = 1296.5), 5 microg, were premixed in the solid state. The matrix mixture was then co-ground with the PP sample containing the HALS in liquid nitrogen using a freezer mill. The powdered sample mixture was spotted on the sample plate, suspended in ion-exchanged water, dried to adhere on the plate, and subjected to MALDI-MS. Three series of the HALS components accompanied by the oxidized species were clearly observed as their molecular ions (M*+)) along with that of the internal standard in the mass spectra. A fairly good linear relationship (R2 = 0.9991) with a relative standard deviation of ca. 11% was observed between the relative peak intensities of the HALS components and the HALS contents ranging from 0.1-2.5 wt%, which could be used as the calibration line to determine the HALS content in PP composites directly by MALDI-MS. The UV-exposed PP composite samples were evaluated by this method to interpret the photostabilizing action of HALS in the PP materials based on the observed change in the relative abundances of the original and oxidized HALS components as a function of UV-exposure time. Copyright 2006 John Wiley & Sons, Ltd.

  11. Hindered rotor tunneling splittings: an application of the two-dimensional non-separable method to benzyl alcohol and two of its fluorine derivatives.

    Science.gov (United States)

    Alves, Tiago Vinicius; Simón-Carballido, Luis; Ornellas, Fernando Rei; Fernández-Ramos, Antonio

    2016-04-07

    In this work we present a novel application of the two-dimensional non-separable (2D-NS) method to the calculation of torsional tunneling splittings in systems with two hindered internal rotors. This method could be considered an extension of one-dimensional methods for the case of compounds with two tops. The 2D-NS method includes coupling between torsions in the kinetic and potential energy. Specifically, it has been applied to benzyl alcohol (BA) and two of its fluorine derivatives: 3-fluorobenzyl alcohol (3FBA) and 4-fluorobenzyl alcohol (4FBA). These molecules present two torsions, i.e., about the -CH2OH (ϕ1) and -OH (ϕ2) groups. The electronic structure calculations to build the two-dimensional torsional potential energy surface were performed at the DF-LMP2-F12//DF-LMP2/cc-pVQZ level of theory. For BA and 4FBA the calculated ground-state vibrational level splittings are 429 and 453 MHz, respectively, in good agreement with the experimental values of 337.10 and 492.82 MHz, respectively. In these two cases there are four equivalent wells and the tunneling splitting is the result of transitions between the two closer minima along ϕ1. The analysis of the wavefunctions, as well as the previous experimental work on the system, supports this conclusion. For 3FBA the observed ground-state splitting is 0.82 MHz, whereas in this case the calculated value amounts only to 0.02 MHz. The 2D-NS method, through the analysis of the wavefunctions, shows that this tiny tunneling splitting occurs between the two most stable minima of the potential energy surface. Additionally, we predict that the first vibrationally excited tunneling splitting will also be small and exclusively due to the interconversion between the second lowest minima.

  12. Factors hindering the development of small-scale municipal hydropower: a case study of the Black River project in Springfield, Vermont

    Energy Technology Data Exchange (ETDEWEB)

    Peters, E.; Berger, G.; Amlin, J.; Meadows, D.

    1979-03-01

    There are many good reasons to use New England's small-scale hydropower resources to generate electricity. But current production capacity in the three northern states is only 1300 MW, just 35% of the 3710 MW estimated to be available to the states. Though the benefits of properly designed projects seem substantial, many factors combine to hinder their development. The Black River project in Springfield, Vermont, exemplifies the problem. Even after the two has invested over five years and $1 million in its effort to develop 30 MW of capacity, it still has not received either federal or state approval to proceed with construction. The first 4 years of the Springfield experience are described and factors that have greatly increased the cost and planning time for the project are identified. The purpose is to identify changes that could facilitate efforts to develop small-scale hydropower at other acceptable sites. On the basis of this experience it is recommended that: after issuance of a FERC permit, a preliminary determination of the project's impacts should be made by FERC officials; if environmental impacts are solely local or limited, environmental analysis/determination should be placed in the hands of the state; short-form licensing should be used for all run-of-river hydro projects that utilize and do not significantly modify existing water impoundment areas and do not significantly alter downstream flow patterns; and a hydro ombudsman with power at the state level should be established to facilitate governmental inter-agency coordination and project-related information transfer: one-stop licensing. (LCL)

  13. Older adults' mental health function and patient-centered care: does the presence of a family companion help or hinder communication?

    Science.gov (United States)

    Wolff, Jennifer L; Roter, Debra L

    2012-06-01

    Late-life mental health disorders are prevalent, costly, and commonly under-diagnosed and under-treated. To investigate whether family companion presence in routine primary care visits helps or hinders patient-centered processes among older adults with poor mental health function. Observational study of accompanied (n = 80) and unaccompanied (n = 310) primary care patients ages 65 and older. Audio-taped medical visit communication, coded with the Roter Interactional Analysis System, and three process measures: visit duration (in minutes), patient/companion verbal activity, and a ratio of patient-centered communication, adjusted for patient age, gender, race, and physical function. Participants were stratified by SF-36 mental health subscale (MCS) using two approaches (1) standardized population midpoint to delineate "good" (50+) and "poor" health (family companion, patient/companions provided less psychosocial information, physicians engaged in less question-asking and partnership-building, and both patient/companions and physicians contributed more task-oriented, biomedical discussion. Accompanied patients with poor mental health were less likely to experience patient-centered communication relative to unaccompanied patients (aOR = 0.21; 95% CI: 0.06, 0.68); no difference was observed for patients with good mental health (aOR = 1.02; 95% CI: 0.46, 2.27). Verbal activity was comparable for accompanied patients/companions and unaccompanied patients in both mental health strata. Medical visits were 2.3 minutes longer when patients with good mental health were accompanied (b = 2.31; p = 0.006), but was comparable for patients with poor mental health (b = -0.37; p = 0.827). Study findings were amplified in the lowest functioning mental health subgroup (MCS communication was least patient-centered (p = 0.019) when these patients were accompanied. Older adults with poor mental health function may experience more communication

  14. Cardiac troponin C-L29Q, related to hypertrophic cardiomyopathy, hinders the transduction of the protein kinase A dependent phosphorylation signal from cardiac troponin I to C.

    Science.gov (United States)

    Schmidtmann, Anja; Lindow, Christopher; Villard, Sylvie; Heuser, Arnd; Mügge, Andreas; Gessner, Reinhard; Granier, Claude; Jaquet, Kornelia

    2005-12-01

    We investigated structural and functional aspects of the first mutation in TNNC1, coding for the calcium-binding subunit (cTnC) of cardiac troponin, which was detected in a patient with hypertrophic cardiomyopathy [ Hoffmann B, Schmidt-Traub H, Perrot A, Osterziel KJ & Gessner R (2001) Hum Mut17, 524]. This mutation leads to a leucine-glutamine exchange at position 29 in the nonfunctional calcium-binding site of cTnC. Interestingly, the mutation is located in a putative interaction site for the nonphosphorylated N-terminal arm of cardiac troponin I (cTnI) [ Finley NL, Abbott MB, Abusamhadneh E, Gaponenko V, Dong W, Seabrook G, Howarth JW, Rana M, Solaro RJ, Cheung HC et al. (1999) EJB Lett453, 107-112]. According to peptide array experiments, the nonphosphorylated cTnI arm interacts with cTnC around L29. This interaction is almost abolished by L29Q, as observed upon protein kinase A-dependent phosphorylation of cTnI at serine 22 and serine 23 in wild-type troponin. With CD spectroscopy, minor changes are observed in the backbone of Ca2+-free and Ca2+-saturated cTnC upon the L29Q replacement. A small, but significant, reduction in calcium sensitivity was detected upon measuring the Ca2+-dependent actomyosin subfragment 1 (actoS1)-ATPase activity and the sliding velocity of thin filaments. The maximum actoS1-ATPase activity, but not the maximum sliding velocity, was significantly enhanced. In addition, we performed our investigations at different levels of protein kinase A-dependent phosphorylation of cTnI. The in vitro assays mainly showed that the Ca2+ sensitivity of the actoS1-ATPase activity, and the mean sliding velocity of thin filaments, were no longer affected by protein kinase A-dependent phosphorylation of cTnI owing to the L29Q exchange in cTnC. The findings imply a hindered transduction of the phosphorylation signal from cTnI to cTnC.

  15. Synthesis, structure, spectra and reactivity of iron(III) complexes of facially coordinating and sterically hindering 3N ligands as models for catechol dioxygenases.

    Science.gov (United States)

    Sundaravel, Karuppasamy; Dhanalakshmi, Thirumanasekaran; Suresh, Eringathodi; Palaniandavar, Mallayan

    2008-12-28

    A series of 1 : 1 iron(III) complexes of sterically hindered and systematically modified tridentate 3N donor ligands have been isolated and studied as functional models for extradiol-cleaving catechol dioxygenases. All of them are of the type [Fe(L)Cl(3)], where L is N-methyl-N'-(pyrid-2-ylmethyl)ethylenediamine (L1), N-ethyl-N'-(pyrid-2-ylmethyl)ethylenediamine (L2), N-benzyl-N'-(pyrid-2-ylmethyl)ethylenediamine (L3), N,N-dimethyl-N'-(pyrid-2-ylmethyl)ethylenediamine (L4), N'-methyl-N'-(pyrid-2-ylmethyl)-N,N-dimethylethylenediamine (L5), N'-ethyl-N'-(pyrid-2-ylmethyl)-N,N-dimethylethylenediamine (L6) and N'-benzyl-N'-(pyrid-2-ylmethyl)-N,N-dimethylethylenediamine (L7). They have been characterized by elemental analysis and spectral and electrochemical methods. The X-ray crystal structures of the complexes [Fe(L2)Cl(3)] 2, [Fe(L3)Cl(3)] 3 and [Fe(L7)Cl(3)] 7 have been successfully determined. All the three complexes possess a distorted octahedral coordination geometry in which the ligand is facially coordinated to iron(III) and the chloride ions occupy the remaining coordination sites. Upon replacing the N-ethyl group on the terminal nitrogen donor in 2 by the bulky N-benzyl group as in 3, the terminal Fe-N bond distance increases slightly from 2.229(5) A to 2.244(5) A. Upon incorporating the sterically demanding N-benzyl group on the central nitrogen donor in 4 to obtain 7, the central Fe-N(amine) bond distance increases from 2.181(5) A to 2.299(2) A. The catecholate adducts [Fe(L)(DBC)(Cl)] and [Fe(L)(DBC)(Sol)](+), where H(2)DBC is 3,5-di-tert-butylcatechol and Sol = solvent (H(2)O/DMF), have been generated in situ and their spectral and redox properties and dioxygenase activities have been studied in N,N-dimethylformamide and dichloromethane solutions. The adducts [Fe(L)(DBC)(Sol)](+) undergo cleavage of DBC(2-) in the presence of molecular oxygen to afford both intra- and extradiol cleavage products. The extradiol products are higher in dichloromethane than in

  16. What factors help or hinder the achievement of low SES students? An international comparison using TIMSS 2011 8th grade science data

    Science.gov (United States)

    Bruner, Justin L.

    Focusing on science from a cross-country perspective, this study explores the relationship between 8th grade science achievement and student, teacher, and school characteristics. More specifically, this study will pay special attention to low socio-economic status (SES) students and seek to understand why some disadvantaged students are able to have higher than expected achievement in science given their SES while other disadvantaged students are not able to achieve beyond what would be expected given their background. This study will explore the multi-level relationship between the characteristics of students, their teachers, their schools, and student achievement in science. While looking at students in classrooms and in schools, this work will create as precise as possible a measure of student SES by drawing on recommendations of an expert panel commissioned by the National Association of Educational Progress (NAEP) study. The study uses the most recent cycle (2011) of the Trends in International Math and Science Study (TIMSS), to strategically select a six-country sample from the 45 participating countries. This six-country sample was selected by using the country level achievement and the standard deviation of that achievement. This will create a sample that has a range of equality in achievement and strength in achievement. This allows for making comparisons both across and within countries to better understand variations in the factors of student performance, especially for disadvantaged students. This paper builds on the existing research around socio-economic status (SES) and achievement by exploring in more detail the conditions in schools and classrooms around the world that might magnify or reduce the effect of SES on student achievement. The analysis looks at these questions: "What conditions help low SES students achieve higher than what would be expected given their SES?" and "What conditions hinder low SES students to achieve at or below what would

  17. Rapid assembly of the doubly-branched pentasaccharide domain of the immunoadjuvant jujuboside A via convergent B(C6F5)3-catalyzed glycosylation of sterically-hindered precursors.

    Science.gov (United States)

    Karimov, Rashad R; Tan, Derek S; Gin, David Y

    2017-05-30

    A convergent synthesis of the complex, doubly-branched pentasaccharide domain of the natural-product immunoadjuvant jujuboside A is described. The key step is a sterically-hindered glycosylation reaction between a branched trisaccharide trichloroacetimidate glycosyl donor and a disaccharide glycosyl acceptor. Conventional Lewis acids (TMSOTf, BF3·Et2O) were ineffective in this glycosylation, but B(C6F5)3 catalyzed the reaction successfully. Inherent complete diastereoselectivity for the undesired α-anomer was overcome by rational optimization with a nitrile solvent system (1 : 5 t-BuCN/CF3Ph) to provide flexible, effective access to the β-linked pentasaccharide.

  18. Technical Challenges Hindering Development of Robust Wireless ...

    African Journals Online (AJOL)

    Cellular phones have experienced exponential growth over the last two decades, and this growth has continued unabated worldwide, with more than a billion worldwide cell phone users projected in the nearest future. Indeed, cellular phones have become a critical business tool and part of everyday life in most developed ...

  19. Technical Challenges Hindering Development of Robust Wireless ...

    African Journals Online (AJOL)

    PROF. OLIVER OSUAGWA

    2015-12-01

    Dec 1, 2015 ... knowledge, time and determination most of these encryption methods can be cracked and, indeed, several have been compromised. To support applications like electronic commerce and credit card transactions, the wireless network must be secure against such listeners. Wireless networking is also a.

  20. Can Secularism Hinder Democracy? The Turkish Experiment

    National Research Council Canada - National Science Library

    Begüm Burak

    2012-01-01

    ... known that there is another interpretation of secularism in which the state exercises control over religion. The Turkish case represents a unique example in the study of the relationship between secularism and democracy with regard to the dominant role of the state in religious affairs. This study will attempt to analyze the negative impact of the state’s interpretation of secularism on democracy in Turkey.

  1. [What hinders the political participation of women?].

    Science.gov (United States)

    Ramirez, S

    1994-06-01

    Forty years after gaining the right to vote, Colombian women comprise scarcely 8% of persons recently elected to the Colombian Congress. At the municipal and departmental level, women occupy even fewer of the positions. Explanations of women's marginal political participation in terms of stereotypes such as their presumed disinterest or emotionalism reflect androcentric prejudices. Their lack of preparation and social conditioning is also a suspect argument, given that there are no objective forms of measuring preparation for political office, such as examinations or specific requirements. Centers for women's studies have sought explanation in terms of aspects of the social and political organization of society that impede access by women to positions of power. Laws assuring women their political rights have not been sufficient to allow them to participate under equal conditions. The assignment of responsibility for domestic labor exclusively to women is a powerful handicap to their full participation. Moreover, public life has become a costly career in terms of resources, time, and energy. The problem is not that women do not participate in politics, but that they are underrepresented in the centers of power. They comprise half of voters and the majority of members of community and civic associations dealing with problems of everyday life. But the number of women declines as the scale of power increases. Feminists suggest that the problem will not be solved by women assuming the behavior patterns of men. Rather, the governmental and civil elites must overcome norms and practices that perpetuate the subordination of women. Women achieving positions of power should maintain a gender perspective and assist in transforming conditions.

  2. Packaging conditions hindering fungal growth on cheese

    DEFF Research Database (Denmark)

    Nielsen, Per Væggemose; Haasum, Iben

    1997-01-01

    Fungal contamination is one of the most important quality deteriorating factors on cheese. During the last 5 years we have studied in detail the underlying factors controlling these unwanted processes in a collaborative project financed by the Danish Dairy Board and the Ministry of Agriculture...

  3. Solute Partitioning and Hindered Diffusion in Hydrogels

    OpenAIRE

    Liu, David Ezra

    2016-01-01

    Solute uptake and release govern the efficacy of hydrogels in controlled drug delivery, tissue engineering, and chromatographic separations. In soft contact lenses, uptake and release of wetting, packaging, and care-solution agents is extensively employed to improve on-eye lens performance. Key physical parameters are the equilibrium solute partition coefficient and the solute diffusion coefficient in the gel that dictate the amounts and rates of uptake/release, respectively. To investigate t...

  4. Inflammatory monocytes hinder antiviral B cell responses.

    Science.gov (United States)

    Sammicheli, Stefano; Kuka, Mirela; Di Lucia, Pietro; de Oya, Nereida Jimenez; De Giovanni, Marco; Fioravanti, Jessica; Cristofani, Claudia; Maganuco, Carmela G; Fallet, Benedict; Ganzer, Lucia; Sironi, Laura; Mainetti, Marta; Ostuni, Renato; Larimore, Kevin; Greenberg, Philip D; de la Torre, Juan Carlos; Guidotti, Luca G; Iannacone, Matteo

    2016-10-21

    Antibodies are critical for protection against viral infections. However, several viruses, such as lymphocytic choriomeningitis virus (LCMV), avoid the induction of early protective antibody responses by poorly understood mechanisms. Here we analyzed the spatiotemporal dynamics of B cell activation to show that, upon subcutaneous infection, LCMV-specific B cells readily relocate to the interfollicular and T cell areas of the draining lymph node where they extensively interact with CD11b(+)Ly6C(hi) inflammatory monocytes. These myeloid cells were recruited to lymph nodes draining LCMV infection sites in a type I interferon-, CCR2-dependent fashion and they suppressed antiviral B cell responses by virtue of their ability to produce nitric oxide. Depletion of inflammatory monocytes, inhibition of their lymph node recruitment or impairment of their nitric oxide-producing ability enhanced LCMV-specific B cell survival and led to robust neutralizing antibody production. In conclusion, our results identify inflammatory monocytes as critical gatekeepers that prevent antiviral B cell responses and suggest that certain viruses take advantage of these cells to prolong their persistence within the host.

  5. Technical Challenges Hindering Development of Robust Wireless ...

    African Journals Online (AJOL)

    PROF. OLIVER OSUAGWA

    2015-12-01

    Dec 1, 2015 ... currently poised to supplement or replace wired networks in many businesses and campuses. Many new applications, including ... The explosive growth of wireless systems coupled with the proliferation of laptop and palmtop computers ..... electronic commerce and credit card transactions, the wireless ...

  6. Conformation of hindered piperidines: Spectroscopic evidence for ...

    Indian Academy of Sciences (India)

    Administrator

    C NMR; conformational analysis; boat forms. 1. Introduction. Many piperidine derivatives are found to possess pharmacological activity and form an essential part of the molecular structure of important drugs. 1. Most of the piperidine precursors are known to exist in chair conformation. Electron withdrawing groups. (–NO ...

  7. Conformation of hindered piperidines: Spectroscopic evidence for ...

    Indian Academy of Sciences (India)

    At room temperature the (3)-benzyl-(2),(6)-bis(aryl)piperidin-4-ones 1-4 exist in only one isomeric form whereas their -nitroso derivatives 5-8 exist in two isomeric forms. The preferred conformations of both the isomeric forms of nitrosamines were determined by comparison of the spectral data with those of the ...

  8. Toward the understanding of chemical absorption processes for post-combustion capture of carbon dioxide: electronic and steric considerations from the kinetics of reactions of CO2(aq) with sterically hindered amines.

    Science.gov (United States)

    Conway, William; Wang, Xiaoguang; Fernandes, Debra; Burns, Robert; Lawrance, Geoffrey; Puxty, Graeme; Maeder, Marcel

    2013-01-15

    The present study reports (a) the determination of both the kinetic rate constants and equilibrium constants for the reaction of CO(2)(aq) with sterically hindered amines and (b) an attempt to elucidate a fundamental chemical understanding of the relationship between the amine structure and chemical properties of the amine that are relevant for postcombustion capture of CO(2) (PCC) applications. The reactions of CO(2)(aq) with a series of linear and methyl substituted primary amines and alkanolamines have been investigated using stopped-flow spectrophotometry and (1)H NMR measurements at 25.0 °C. The specific mechanism of absorption for each of the amines, that is CO(2) hydration and/or carbamate formation, is examined and, based on the mechanism, the kinetic and equilibrium constants for the formation of carbamic acid/carbamates, including protonation constants of the carbamate, are reported for amines that follow this pathway. A Brønsted correlation relating the kinetic rate constants and equilibrium constants for the formation of carbamic acid/carbamates with the protonation constant of the amine is reported. Such a relationship facilitates an understanding of the effects of steric and electronic properties of the amine toward its reactivity with CO(2). Further, such relationships can be used to guide the design of new amines with improved properties relevant to PCC applications.

  9. Factors that hinder of integrality in dialysis care Factores que dificultan la integralidad del cuidado en hemodiálisis Fatores que dificultam a integralidade no cuidado em hemodiálise

    Directory of Open Access Journals (Sweden)

    Cinthia Dalasta Caetano Fujii

    2011-08-01

    Full Text Available This study analyzes the factors, which from the perspective of the health team and users, hinder the implementation of integrality in care provided by a dialysis facility. This qualitative study collected data through semi-structured interviews held with 16 health professionals and eight users from a university hospital in Rio Grande do Sul, Brazil. Data were analyzed through thematic content analysis. Among the factors that hinder the implementation of integrality in hemodialysis care, the following were highlighted: a deficient service network, delay in accessing diagnostic exams and consultations with specialists, and a reduced number of professionals in the support team. The conclusion is that the health services network needs to be expanded and an effective interface between such networks and dialysis services needs to be established in order to overcome the reported difficulties and contribute to the implementation of integrality in dialysis care.Este artículo tuvo como objetivo analizar, bajo la óptica del equipo de salud y de los usuarios, los factores que pueden dificultar la práctica de la integralidad del cuidado en una unidad de hemodiálisis. Se trata de investigación cualitativa, cuyos datos fueron recolectados, por medio de entrevista semiestructurada, con dieciséis profesionales de salud y ocho usuarios de un hospital de enseñanza de Rio Grande del Sur, habiendo sido, posteriormente, hecho el análisis de contenido temático. Ese análisis sugiere que, entre los factores que dificultan la práctica de la integralidad en el cuidado en hemodiálisis, se destacaron deficiencias en la red de servicios, demora en el acceso a exámenes de diagnóstico y a consultas con médicos especialistas, y reducido número de profesionales en los equipos de apoyo. Se concluye, entonces, que la ampliación en la red de servicios de salud y el establecimiento de una conexión efectiva entre los servicios de hemodiálisis y esa red podr

  10. What are the views of hospital-based generalist palliative care professionals on what facilitates or hinders collaboration with in-patient specialist palliative care teams? A systematically constructed narrative synthesis.

    Science.gov (United States)

    Firn, Janice; Preston, Nancy; Walshe, Catherine

    2016-03-01

    Hospital-based specialist palliative care services are common, yet existing evidence of inpatient generalist providers' perceptions of collaborating with hospital-based specialist palliative care teams has never been systematically assessed. To assess the existing evidence of inpatient generalist palliative care providers' perceptions of what facilitates or hinders collaboration with hospital-based specialist palliative care teams. Narrative literature synthesis with systematically constructed search. PsycINFO, PubMed, Web of Science, Cumulative Index of Nursing and Allied Health Literature and ProQuest Social Services databases were searched up to December 2014. Individual journal, citation and reference searching were also conducted. Papers with the views of generalist inpatient professional caregivers who utilised hospital-based specialist palliative care team services were included in the narrative synthesis. Hawker's criteria were used to assess the quality of the included studies. Studies included (n = 23) represented a variety of inpatient generalist palliative care professionals' experiences of collaborating with specialist palliative care. Effective collaboration is experienced by many generalist professionals. Five themes were identified as improving or decreasing effective collaboration: model of care (integrated vs linear), professional onus, expertise and trust, skill building versus deskilling and specialist palliative care operations. Collaboration is fostered when specialist palliative care teams practice proactive communication, role negotiation and shared problem-solving and recognise generalists' expertise. Fuller integration of specialist palliative care services, timely sharing of information and mutual respect increase generalists' perceptions of effective collaboration. Further research is needed regarding the experiences of non-physician and non-nursing professionals as their views were either not included or not explicitly reported.

  11. Assessment of new limit values for wind turbines. Influence of different limit values on exposure, annoyance and potential development locations; Evaluatie nieuwe normstelling windturbinegeluid. Invloed van verschillende grenswaarden op blootstelling, hinder en mogelijkheden ontwikkelingslocaties

    Energy Technology Data Exchange (ETDEWEB)

    Verheijen, E.; Jabben, J.; Schreurs, E.; Koeman, T.; Van Poll, R.; Du Pon, B.

    2009-07-01

    framework of energy policy targets and the risk of extra noise health effects from exposure to low-frequency noise were evaluated. [Dutch] Ongeveer 1500 omwonenden rondom de huidige windturbines in Nederland hebben kans op ernstige geluidhinder. Een richtwaarde van 40 decibel (dB) in de nieuwe regelgeving voor windturbines kan een verdere toename tot een minimum beperken als nieuwe windturbines worden gerealiseerd. Boven de 45 dB zijn in toenemende mate hinderklachten en gezondheidsproblemen te verwachten. In vergelijking met andere typen geluidbronnen ontstaan bij windturbines eerder hindereffecten voor omwonenden bij een lagere geluidbelasting. De keuze van grenswaarden heeft gevolgen voor de hoeveelheid ruimte op land die beschikbaar is voor nieuwe windturbines. Geschat wordt dat een grenswaarde van 40 dB ruimte biedt voor 7000 megawatt aan duurzame energie via nieuwe windturbines. Een grenswaarde van 45 dB biedt meer ruimte, ongeveer voor 25.000 megawatt. Momenteel is een nieuw wetsvoorstel in voorbereiding dat eisen stelt aan de geluidimmissie van nieuwe windturbines in Nederland. Het wetsvoorstel beoogt de geluidhinder van nieuwe turbines te beperken bij realisatie van de doelstellingen van het kabinet voor duurzame energie. Net als in de wetgeving voor weg- en railverkeersgeluid wordt in het wetsvoorstel een richtwaarde en een maximale grenswaarde voor de geluidbelasting (in Lden) van woningen gesteld. Onder de richtwaarde zijn er geen belemmeringen om nieuwe windturbines te plaatsen; boven de maximale grenswaarde kan het bevoegde gezag geen vergunning verlenen. Tussen deze waarden zullen belangen via een inspraakprocedure worden afgewogen. Het RIVM heeft de mogelijke consequenties bij verschillende grenswaarden onderzocht. Gekeken is naar de kans op geluidhinder, plaatsingsruimte voor nieuwe turbines in relatie tot energiedoelstellingen en risico's op extra hinder door laagfrequent geluid.

  12. Butlletí de prevenció d'errors de medicació de Catalunya - 2003, Volum 01, Número 02, maig - agost

    OpenAIRE

    2003-01-01

    Errors de medicació; Prescripció de medicaments Medication errors; Drug prescription Errores de medicación; Prescripción de medicamentos Mètodes de detecció d'errors de medicació / Errors relacionats amb la forma farmacèutica / Exemples d'errors de forma farmacèutica notificats i mesures de millora / Dades estadístiques del programa de prevenció d’errors de medicació / Bibliografia d’interès sobre errors de medicació Métodos de detección de errores de medicación / Errores relacion...

  13. Silencing of Carbohydrate Sulfotransferase 15 Hinders Murine Pulmonary Fibrosis Development

    Directory of Open Access Journals (Sweden)

    Yoshiro Kai

    2017-03-01

    Full Text Available Pulmonary fibrosis is a progressive lung disorder characterized by interstitial fibrosis, for which no effective treatments are available. Chondroitin sulfate proteoglycan (CSPG has been shown to be a mediator, but the specific component of glycosaminoglycan chains of CSPG has not been explored. We show that chondroitin sulfate E-type (CS-E is involved in fibrogenesis. Small interfering RNA (siRNA targeting carbohydrate sulfotransferase 15 (CHST15 was designed to inhibit CHST15 mRNA and its product, CS-E. CS-E augments cell contraction and CHST15 siRNA inhibits collagen production. We found that bleomycin treatment increased CHST15 expression in interstitial fibroblasts at day 14. CHST15 siRNA was injected intranasally on days 1, 4, 8, and 11, and CHST15 mRNA was significantly suppressed by day 14. CHST15 siRNA reduced lung CSPG and the grade of fibrosis. CHST15 siRNA repressed the activation of fibroblasts, as evidenced by suppressed expression of α smooth muscle actin (αSMA, connective tissue growth factor (CTGF, lysyl oxidase like 2 (LOXL2, and CC-chemokine ligand 2 (CCL2/monocyte chemoattractant protein-1 (MCP-1. Inflammatory infiltrates in the bronchoalveolar lavage fluid (BALF and interstitium were diminished by CHST15 siRNA. These results indicate a pivotal role for CHST15 in fibroblast-mediated lung fibrosis and suggest a possible new therapeutic role for CHST15 siRNA in pulmonary fibrosis.

  14. What Hinders Electron Transfer Dissociation (ETD) of DNA Cations?

    Science.gov (United States)

    Hari, Yvonne; Leumann, Christian J.; Schürch, Stefan

    2017-09-01

    Radical activation methods, such as electron transfer dissociation (ETD), produce structural information complementary to collision-induced dissociation. Herein, electron transfer dissociation of 3-fold protonated DNA hexamers was studied to gain insight into the fragmentation mechanism. The fragmentation patterns of a large set of DNA hexamers confirm cytosine as the primary target of electron transfer. The reported data reveal backbone cleavage by internal electron transfer from the nucleobase to the phosphate linker leading either to a•/w or d/z• ion pairs. This reaction pathway contrasts with previous findings on the dissociation processes after electron capture by DNA cations, suggesting multiple, parallel dissociation channels. However, all these channels merely result in partial fragmentation of the precursor ion because the charge-reduced DNA radical cations are quite stable. Two hypotheses are put forward to explain the low dissociation yield of DNA radical cations: it is either attributed to non-covalent interactions between complementary fragments or to the stabilization of the unpaired electron in stacked nucleobases. MS3 experiments suggest that the charge-reduced species is the intact oligonucleotide. Moreover, introducing abasic sites significantly increases the dissociation yield of DNA cations. Consequently, the stabilization of the unpaired electron by π-π-stacking provides an appropriate rationale for the high intensity of DNA radical cations after electron transfer. [Figure not available: see fulltext.

  15. Facilitating or hindering social cohesion? The impact of the ...

    African Journals Online (AJOL)

    This article discusses the contribution of the Community Work Programme (CWP) to social cohesion, a term that is widely used in post-apartheid South Africa.1 The article is based on a study that examined the contribution of the CWP to violence prevention. The study by researchers from the Centre for the Study of Violence ...

  16. Constraints that help or hinder creative performance : A motivational approach

    NARCIS (Netherlands)

    Roskes, Marieke

    2015-01-01

    Threatening situations, in which people fear negative outcomes or failure, evoke avoidance motivation. Avoidance motivation, in turn, evokes a focused, systematic and effortful way of information processing that has often been linked to reduced creativity. This harmful effect of avoidance motivation

  17. Factors that Hinder Parents from the Communicating of Sexual ...

    African Journals Online (AJOL)

    Parent-adolescent communication about sexual matters is one of the means that encourages adolescents to adopt responsible sexual behaviour ... in communication including reproductive health matters. Despite the efforts by these .... Then, knowledge variables were dichotomized into right or wrong responses and overall ...

  18. Ethnic Minorities’ Impression Management in the Interview: Helping or Hindering?

    OpenAIRE

    Derous, Eva

    2017-01-01

    Cross-cultural impression management (IM) has not been considered much, which is remarkable given the fast rate at which the labor market is becoming multicultural. This study investigated whether ethnic minorities and majorities differed in their preference for IM-tactics and how this affected ethnic minorities’ interview outcomes. A preliminary study (focus groups/survey) showed that ethnic minorities (i.e., Arab/Moroccans) preferred ‘entitlements’ whereas majorities (i.e., Flemish/Belgians...

  19. Does Inward FDI Promote or Hinder Outward FDI?

    DEFF Research Database (Denmark)

    Liu, Ying; Li, Ming Hua; Lu, Jiangyong

    In this paper we evaluate the mechanisms underlying dynamic linkages between inward FDI and outward internationalization in the Chinese automobile industry. While several studies have examined the relationship between outward and inward investment using empirical data, this is among the first to ...... may be more driven to expand internationally while firms with IJVs may face constraints from venturing abroad. Our study further delineates strategies for how automakers without IJVs may rely on external growth to springboard back into the domestic car market.......In this paper we evaluate the mechanisms underlying dynamic linkages between inward FDI and outward internationalization in the Chinese automobile industry. While several studies have examined the relationship between outward and inward investment using empirical data, this is among the first...... to employ a case study approach to investigate how international joint ventures (IJVs) established between foreign and Chinese carmakers can shape their internationalization speed, proclivity, and degree. We discuss some unique features of carmakers with and without IJVs to elucidate how firms without IJVs...

  20. Soil humic substances hinder the propagation of prions

    Science.gov (United States)

    Leita, Liviana; Giachin, Gabriele; Margon, Alja; Narkiewicz, Joanna; Legname, Giuseppe

    2013-04-01

    Prions are infectious pathogens causing fatal neurodegenerative disorders, known as transmissible spongiform encephalopathies (TSEs), or prion diseases, which affect different mammalian species. TSEs include scrapie in sheep, bovine spongiform encephalopathy (BSE) in cattle, chronic wasting disease (CWD) in mule deer, elk, and moose (cervids), and Creutzfeldt-Jakob disease (CJD) in humans. The prominent, if not only, component of prions is a misfolded conformer (PrPSc) of a constitutive sialoglycoprotein, the cellular prion protein (PrPC). A notable feature of prion diseases is horizontal transmission between grazing animals, implying that contaminated soil may serve to propagate the disease. In this respect, it has been reported that grazing animals ingest from tens to hundreds grams of soil per day, either incidentally through the diet, or deliberately in answering salt needs, and that mule deer can develop CWD after grazing in locations that previously housed infected animals. Prions may enter the environment through different routes, including animal excreta and secreta which mainly contribute to soil contamination. Recent studies have proven that prions can be retained in soil, which could act as a carrier of infectivity even several years after the contamination. However, within the large spread of potentially infected lands, prion diseases have become endemic only in geographically limited regions. The reasons for this geographical distribution remain unknown, but it suggests a role of the different kinds of soil in either enhancing or attenuating prion infectivity. The extent of prion transmission from the contaminated environment is unknown. Several studies have tried to address the issue of prion interaction with soil, but, at the present, different approaches show several drawbacks and technical difficulties, as soil is a complex, multi-component system of both mineral and organic interacting substances. Most research has focused on the adsorption capacity of clay minerals; however the contribution of soil organic components in adsorption has so far been neglected, as they represent a minor soil fraction on a weight basis. Among organic molecules, humic substances (HSs) are natural polyanions that result among the most reactive compounds in the soil and possess the largest specific surface area. Humic substances make up a large portion of the dark matter in humus and consist of heterogeneous mixtures of transformed biomolecules exhibiting a supramolecular structure. HSs are classified as humic acids (HAs), which are soluble only in alkaline solutions, and fulvic acids (FAs), which are soluble in both alkaline and acid solutions. The amphiphilic characteristics confer to HAs and FAs great versatility to interact with xenobiotics and reasonably also with prion proteins and/or prions too, leading to the formation of adducts with peculiar chemical and biophysical characteristics, thus affecting the transport, fixation and toxicity of prion. Results from our chemical, biophysical and biochemical investigation will be presented and results on anti-prion activity exerted by HAs and FAs will be provided, thus suggesting that amendment of contaminated soil with humic substances could be a strategy to contrast prion diffusion.

  1. Factors Motivating and Hindering Information and Communication Technologies Action Competence

    Science.gov (United States)

    Kurt, Adile Askim; Akbulut, Yavuz; Odabasi, H. Ferhan; Ceylan, Beril; Kuzu, Elif Bugra; Donmez, Onur; Izmirli, Ozden Sahin

    2013-01-01

    Information and Communication Technologies Action Competence (ICTAC) can be defined as "individuals' motivation and capacity to voluntarily employ their ICT skills for initiating or taking part in civic actions". Since academic staff and teachers in ICT related fields have crucial roles in training action-competent individuals, this…

  2. Congressional Oversight of Homeland Security: Help or Hinderance?

    Science.gov (United States)

    2012-12-01

    207 These committees, however, were not an innovation of the 1946 reorganization of Congress. Prior to 1946, the House and Senate had a Military...Eisenhower took office congressional critics were equally critical of his “New Look” defense strategy , which favored technology over manpower.214 For...1956, the SASC identified what they viewed as a duplication of efforts between the Army and the Air Force. The Army had sought to fund a Nike

  3. Capacity shortfalls hinder the performance of marine protected areas globally

    Science.gov (United States)

    Gill, David A.; Mascia, Michael B.; Ahmadia, Gabby N.; Glew, Louise; Lester, Sarah E.; Barnes, Megan; Craigie, Ian; Darling, Emily S.; Free, Christopher M.; Geldmann, Jonas; Holst, Susie; Jensen, Olaf P.; White, Alan T.; Basurto, Xavier; Coad, Lauren; Gates, Ruth D.; Guannel, Greg; Mumby, Peter J.; Thomas, Hannah; Whitmee, Sarah; Woodley, Stephen; Fox, Helen E.

    2017-03-01

    Marine protected areas (MPAs) are increasingly being used globally to conserve marine resources. However, whether many MPAs are being effectively and equitably managed, and how MPA management influences substantive outcomes remain unknown. We developed a global database of management and fish population data (433 and 218 MPAs, respectively) to assess: MPA management processes; the effects of MPAs on fish populations; and relationships between management processes and ecological effects. Here we report that many MPAs failed to meet thresholds for effective and equitable management processes, with widespread shortfalls in staff and financial resources. Although 71% of MPAs positively influenced fish populations, these conservation impacts were highly variable. Staff and budget capacity were the strongest predictors of conservation impact: MPAs with adequate staff capacity had ecological effects 2.9 times greater than MPAs with inadequate capacity. Thus, continued global expansion of MPAs without adequate investment in human and financial capacity is likely to lead to sub-optimal conservation outcomes.

  4. Hindered internal rotation in some singly methylated trans-stilbenes

    Energy Technology Data Exchange (ETDEWEB)

    Spangler, L.H.; Bosma, W.B.; van Zee, R.D.; Zwier, T.S.

    1988-06-01

    The fluorescence excitation and several dispersed fluorescence spectra for supersonically cooled p-methyl-trans-stilbene and the two m-methyl-trans-stilbenes are presented. Despite significant spectral congestion present in these molecules which contain low frequency modes and internal rotation structure, nearly complete assignments of the excitation spectra are given. One notable transition is assigned as a combination of a nontotally symmetric vibration and a nontotally symmetric level of the methyl rotor. All three species have a ground state barrier to internal rotation of approx.28 cm/sup -1/. Excited state barriers and conformational changes observed on excitation are 150 cm/sup -1/ and 35/sup 0/ for p-Me, and 80 cm/sup -1/ and 60/sup 0/, and 186 cm/sup -1/ and 30/sup 0/ for the two m-Me compounds. The p-Me compound shows a threefold barrier to internal rotation rather than a sixfold one, indicating that the two meta positions are inequivalent. The large differences in barrier height and conformational change on excitation between the two meta isomers, whose origins are separated by 207 cm/sup -1/, confirm this inequivalence.

  5. Quantum Synchronization Blockade: Energy Quantization Hinders Synchronization of Identical Oscillators.

    Science.gov (United States)

    Lörch, Niels; Nigg, Simon E; Nunnenkamp, Andreas; Tiwari, Rakesh P; Bruder, Christoph

    2017-06-16

    Classically, the tendency towards spontaneous synchronization is strongest if the natural frequencies of the self-oscillators are as close as possible. We show that this wisdom fails in the deep quantum regime, where the uncertainty of amplitude narrows down to the level of single quanta. Under these circumstances identical self-oscillators cannot synchronize and detuning their frequencies can actually help synchronization. The effect can be understood in a simple picture: Interaction requires an exchange of energy. In the quantum regime, the possible quanta of energy are discrete. If the extractable energy of one oscillator does not exactly match the amount the second oscillator may absorb, interaction, and thereby synchronization, is blocked. We demonstrate this effect, which we coin quantum synchronization blockade, in the minimal example of two Kerr-type self-oscillators and predict consequences for small oscillator networks, where synchronization between blocked oscillators can be mediated via a detuned oscillator. We also propose concrete implementations with superconducting circuits and trapped ions. This paves the way for investigations of new quantum synchronization phenomena in oscillator networks both theoretically and experimentally.

  6. What Hinders Electron Transfer Dissociation (ETD) of DNA Cations?

    Science.gov (United States)

    Hari, Yvonne; Leumann, Christian J.; Schürch, Stefan

    2017-12-01

    Radical activation methods, such as electron transfer dissociation (ETD), produce structural information complementary to collision-induced dissociation. Herein, electron transfer dissociation of 3-fold protonated DNA hexamers was studied to gain insight into the fragmentation mechanism. The fragmentation patterns of a large set of DNA hexamers confirm cytosine as the primary target of electron transfer. The reported data reveal backbone cleavage by internal electron transfer from the nucleobase to the phosphate linker leading either to a•/ w or d/ z• ion pairs. This reaction pathway contrasts with previous findings on the dissociation processes after electron capture by DNA cations, suggesting multiple, parallel dissociation channels. However, all these channels merely result in partial fragmentation of the precursor ion because the charge-reduced DNA radical cations are quite stable. Two hypotheses are put forward to explain the low dissociation yield of DNA radical cations: it is either attributed to non-covalent interactions between complementary fragments or to the stabilization of the unpaired electron in stacked nucleobases. MS3 experiments suggest that the charge-reduced species is the intact oligonucleotide. Moreover, introducing abasic sites significantly increases the dissociation yield of DNA cations. Consequently, the stabilization of the unpaired electron by π-π-stacking provides an appropriate rationale for the high intensity of DNA radical cations after electron transfer. [Figure not available: see fulltext.

  7. Hindered dissolution of fibrin formed under mechanical stress.

    Science.gov (United States)

    Varjú, I; Sótonyi, P; Machovich, R; Szabó, L; Tenekedjiev, K; Silva, M M C G; Longstaff, C; Kolev, K

    2011-05-01

    Recent data indicate that stretching forces cause a dramatic decrease in clot volume accompanied by gross conformational changes of fibrin structure. The present study attempts to characterize the lytic susceptibility of fibrin exposed to mechanical stress as a model for fibrin structures observed in vivo. The relevance of stretched fibrin models was substantiated by scanning electron microscopic (SEM) evaluation of human thrombi removed during surgery, where surface fibrin fibers were observed to be oriented in the direction of shear forces, whereas interior fibers formed a random spatial meshwork. These structural variations were modeled in vitro with fibrin exposed to adjustable mechanical stress. After two- and three-fold longitudinal stretching (2 × S, 3 × S) the median fiber diameter and pore area in SEM images of fibrin decreased two- to three-fold. Application of tissue plasminogen activator (tPA) to the surface of model clots, which contained plasminogen, resulted in plasmin generation which was measured in the fluid phase. After 30-min activation 12.6 ± 0.46 pmol mm(-2) plasmin was released from the non-stretched clot (NS), 5.5 ± 1.11 pmol mm(-2) from 2 × S and 2.3 ± 0.36 pmol mm(-2) from 3 × S clot and this hampered plasmin generation was accompanied by decreased release of fibrin degradation products from stretched fibrins. Confocal microscopic images showed that a green fluorescent protein-fusion variant of tPA accumulated in the superficial layer of NS, but not in stretched fibrin. Mechanical stress confers proteolytic resistance to fibrin, which is a result of impaired plasminogen activation coupled to lower plasmin sensitivity of the denser fibrin network. © 2011 International Society on Thrombosis and Haemostasis.

  8. Does attitude hinder or help selecting evaluation questions?

    Directory of Open Access Journals (Sweden)

    Behzad Shams

    2015-01-01

    Full Text Available Background: Positive attitude leads to a more successfully implementation of a change. We investigated the effect of attitudes of stakeholders toward a program on their prioritization of the program components for selecting the key question of a theory-driven evaluation with concept mapping method. Materials and Methods: During a brainstorming session, stated statements defined the program components. Then they were sorted and rated regarding the importance and feasibility of them. In addition, the attitudes of participants were assessed by a 30 items questionnaire extracted from a pool named as "50 reasons not to change." We determined and compared the consensus points of participants both with and without of considering their attitudes toward the program. Results: The participants were divided into two groups of high (45% - above the mean and low (55% - below the mean attitude. Brainstorming discussions generated a pool of almost 120 statements which were subsequently refined to 44 statements. Matching the rating scores between two attitude groups yielded a consensus at a higher priority than the other method. Conclusion: In the concept mapping procedure, it is crucial to reach the consensus with respect to the participants′ attitude, rather than the similarity of mean scores of feasibility and importance.

  9. Factors hindering socio-cultural integration of international students ...

    African Journals Online (AJOL)

    The results indicate that many international students suffer psychological feelings and struggling with cross-cultural adjustment. Language barrier, life style and xenophobia were trendy among a myriad of other factors. While some seems very reserved to avoid conflicts, many have high self-efficacy to set goals which are ...

  10. Ethnic Minorities' Impression Management in the Interview: Helping or Hindering?

    Science.gov (United States)

    Derous, Eva

    2017-01-01

    Cross-cultural impression management (IM) has not been considered much, which is remarkable given the fast rate at which the labor market is becoming multicultural. This study investigated whether ethnic minorities and majorities differed in their preference for IM-tactics and how this affected ethnic minorities' interview outcomes. A preliminary study (focus groups/survey) showed that ethnic minorities (i.e., Arab/Moroccans) preferred 'entitlements' whereas majorities (i.e., Flemish/Belgians) preferred 'opinion conformity' as IM-tactics. An experimental follow-up study among 163 ethnic majority raters showed no main effect of IM-tactics on interview ratings. Ethnic minorities' use of IM-tactics only affected interview ratings if rater characteristics were considered. Specifically, interview ratings were higher when ethnic minorities used opinion conformity (i.e., majority-preferred IM-tactic) and lower when minorities used entitlements (i.e., minority-preferred IM-tactic) if recruiters were high in social dominance orientation, and when they felt more experienced/proficient with interviewing. IM-tactics are a human capital factor that might help applicants to increase their job chances on the labor market. It is concluded that ethnic minority applicants' preferences for certain IM-tactics might lead to bias even in structured interview settings, but that this depends on ethnic majority recruiters' interview experience and ingroup/outgroup attitudes. Implications for research and practice are discussed.

  11. Do misconceptions hinder effective inhalation therapy with dry powder inhalers?

    NARCIS (Netherlands)

    De Boer, A.H.; Hagedoorn, P.H.; Frijlink, H.W.F.

    Purpose: It is widely believed that high resistance dry powder inhalers (DPI's) can not be operated adequately by patients with reduced vital capacity and that a constant lung deposition requires a flow rate independent fine particle output (FPF). These beliefs may result in incorrect use and

  12. Ethnic Minorities’ Impression Management in the Interview: Helping or Hindering?

    Science.gov (United States)

    Derous, Eva

    2017-01-01

    Cross-cultural impression management (IM) has not been considered much, which is remarkable given the fast rate at which the labor market is becoming multicultural. This study investigated whether ethnic minorities and majorities differed in their preference for IM-tactics and how this affected ethnic minorities’ interview outcomes. A preliminary study (focus groups/survey) showed that ethnic minorities (i.e., Arab/Moroccans) preferred ‘entitlements’ whereas majorities (i.e., Flemish/Belgians) preferred ‘opinion conformity’ as IM-tactics. An experimental follow-up study among 163 ethnic majority raters showed no main effect of IM-tactics on interview ratings. Ethnic minorities’ use of IM-tactics only affected interview ratings if rater characteristics were considered. Specifically, interview ratings were higher when ethnic minorities used opinion conformity (i.e., majority-preferred IM-tactic) and lower when minorities used entitlements (i.e., minority-preferred IM-tactic) if recruiters were high in social dominance orientation, and when they felt more experienced/proficient with interviewing. IM-tactics are a human capital factor that might help applicants to increase their job chances on the labor market. It is concluded that ethnic minority applicants’ preferences for certain IM-tactics might lead to bias even in structured interview settings, but that this depends on ethnic majority recruiters’ interview experience and ingroup/outgroup attitudes. Implications for research and practice are discussed. PMID:28203211

  13. Do Baseline Requirements Hinder Trades in Water Quality Programs?

    OpenAIRE

    Ghosh, Gaurav; Ribaudo, Marc; Shortle, James

    2009-01-01

    The Environmental Protection Agency and the U.S. Department of Agriculture are promoting point/nonpoint trading as a way of reducing the costs of meeting water quality goals while giving nonpoint sources a larger role in meeting those goals. Farms can create offsets or credits in a point/nonpoint trading program by implementing management practices such as conservation tillage, nutrient management, and buffer strips. To be eligible to sell credits, farmers must first comply with baseline requ...

  14. Do baseline requirements hinder trades in water quality trading programs?

    OpenAIRE

    Ribaudo, Marc; Ghosh, Gaurav S.; Shortle, James S.

    2009-01-01

    The Environmental Protection Agency and the U.S. Department of Agriculture are promoting point/nonpoint trading as a way of reducing the costs of meeting water quality goals while giving nonpoint sources a larger role in meeting those goals. Farms can create offsets or credits in a point/nonpoint trading program by implementing management practices such as conservation tillage, nutrient management, and buffer strips. To be eligible to sell credits, farmers must first comply with baseline requ...

  15. Visual Information Can Hinder Working Memory Processing of Speech

    Science.gov (United States)

    Mishra, Sushmit; Lunner, Thomas; Stenfelt, Stefan; Ronnberg, Jerker; Rudner, Mary

    2013-01-01

    Purpose: The purpose of the present study was to evaluate the new Cognitive Spare Capacity Test (CSCT), which measures aspects of working memory capacity for heard speech in the audiovisual and auditory-only modalities of presentation. Method: In Experiment 1, 20 young adults with normal hearing performed the CSCT and an independent battery of…

  16. Tumor Vessel Compression Hinders Perfusion of Ultrasonographic Contrast Agents1

    Science.gov (United States)

    Galiè, Mirco; D'Onofrio, Mirko; Montani, Maura; Amici, Augusto; Calderan, Laura; Marzola, Pasquina; Benati, Donatella; Merigo, Flavia; Marchini, Cristina; Sbarbati, Andrea

    2005-01-01

    Abstract Contrast-enhanced ultrasound (CEUS) is an advanced approach to in vivo assessment of tumor vascularity and is being increasingly adopted in clinical oncology. It is based on 1- to 10 µm-sized gas microbubbles, which can cross the capillary beds of the lungs and are effective echo enhancers. It is known that high cell density, high transendothelial fluid exchange, and poorly functioning lymphatic circulation all provoke solid stress, which compresses vessels and drastically reduces tumor blood flow. Given their size, we supposed that the perfusion of microbubbles is affected by anatomic features of tumor vessels more than are contrast agents traditionally used in dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). Here, we compared dynamic information obtained from CEUS and DCE-MRI on two experimental tumor models exhibiting notable differences in vessel anatomy. We found that tumors with small, flattened vessels show a much higher resistance to microbubble perfusion than to MRI contrast agents, and appear scarcely vascularized at CEUS examination, despite vessel volume adequate for normal function. Thus, whereas CEUS alone could induce incorrect diagnosis when tumors have small or collapsed vessels, integrated analysis using CEUS and DCE-MRI allows in vivo identification of tumors with a vascular profile frequently associated with malignant phenotypes. PMID:15967105

  17. DNA replication is intrinsically hindered in terminally differentiated myotubes.

    Directory of Open Access Journals (Sweden)

    Deborah Pajalunga

    2010-07-01

    Full Text Available Terminally differentiated (TD cells permanently exit the mitotic cycle while acquiring specialized characteristics. Although TD cells can be forced to reenter the cell cycle by different means, they cannot be made to stably proliferate, as attempts to induce their replication constantly result in cell death or indefinite growth arrest. There is currently no biological explanation for this failure.Here we show that TD mouse myotubes, reactivated by depletion of the p21 and p27 cell cycle inhibitors, are unable to complete DNA replication and sustain heavy DNA damage, which triggers apoptosis or results in mitotic catastrophe. In striking contrast, quiescent, non-TD fibroblasts and myoblasts, reactivated in the same way, fully replicate their DNA, do not suffer DNA damage, and proliferate even in the absence of growth factors. Similar results are obtained when myotubes and fibroblasts are reactivated by forced expression of E1A or cyclin D1 and cdk4.We conclude that the inability of myotubes to complete DNA replication must be ascribed to peculiar features inherent in their TD state, rather than to the reactivation method. On reviewing the literature concerning reactivation of other TD cell types, we propose that similar mechanisms underlie the general inability of all kinds of TD cells to proliferate in response to otherwise mitogenic stimuli. These results define an unexpected basis for the well known incompetence of mammalian postmitotic cells to proliferate. Furthermore, this trait might contribute to explain the inability of these cells to play a role in tissue repair, unlike their counterparts in extensively regenerating species.

  18. Hindered protein dynamics in the presence of a cryoprotecting agent

    Energy Technology Data Exchange (ETDEWEB)

    Koeper, I. [Laboratoire Leon Brillouin, CEA Saclay, 91191 Gif-sur-Yvette (France); Physikdepartment E13, TU Muenchen, 85747 Garching (Germany); Bellissent-Funel, M.C. [Laboratoire Leon Brillouin, CEA Saclay, 91191 Gif-sur-Yvette (France)

    2002-07-01

    We present a study of the influence of trehalose, a well-known cryoprotecting disaccharide, on the dynamics of a protein, the C-phycocyanin. The dynamics is investigated in a time range from some picoseconds to several nanoseconds using different neutron-scattering techniques. Data obtained on samples containing hydrated powders of the protein in the presence of trehalose are compared to that of the protein alone, studied by neutron-scattering techniques as well as by molecular dynamics simulations. The analysis of time-of-flight data gives access to the geometry of the observed motions. These motions can be described via a model of a particle diffusing inside a sphere. We observe a slowing down of the movements of the protein due to the presence of trehalose of one to two orders of magnitude, while the geometry of the motions is conserved. (orig.)

  19. Tumor Vessel Compression Hinders Perfusion of Ultrasonographic Contrast Agents

    Directory of Open Access Journals (Sweden)

    Mirco Galiè

    2005-05-01

    Full Text Available Contrast-enhanced ultrasound (CEUS is an advanced approach to in vivo assessment of tumor vascularity and is being increasingly adopted in clinical oncology. It is based on 1- to 10 μm-sized gas microbubbles, which can cross the capillary beds of the lungs and are effective echo enhancers. It is known that high cell density, high transendothelial fluid exchange, and poorly functioning lymphatic circulation all provoke solid stress, which compresses vessels and drastically reduces tumor blood flow. Given their size, we supposed that the perfusion of microbubbles is affected by anatomic features of tumor vessels more than are contrast agents traditionally used in dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI. Here, we compared dynamic information obtained from CEUS and DCE-MRI on two experimental tumor models exhibiting notable differences in vessel anatomy. We found that tumors with small, flattened vessels show a much higher resistance to microbubble perfusion than to MRI contrast agents, and appear scarcely vascularized at CEUS examination, despite vessel volume adequate for normal function. Thus, whereas CEUS alone could induce incorrect diagnosis when tumors have small or collapsed vessels, integrated analysis using CEUS and DCE-MRI allows in vivo identification of tumors with a vascular profile frequently associated with malignant phenotypes.

  20. The Science of Numbers: Does Language Help or Hinder?

    Science.gov (United States)

    Calude, Andreea S.

    2011-01-01

    This paper examines Roy Harris' discussion of number and the language of science in his book "History, Science and the Limits of Language" in light of recent work in cognitive linguistics. While many of his points are valid, linguistic theory has since addressed some of these concerns by formulating usage-based, cognitive frameworks to explore and…

  1. Justice and legitimacy hindered by uncertainty: The legal status of ...

    African Journals Online (AJOL)

    The Traditional Leadership and Governance Framework Act 2003 provides for the transformation of apartheidera tribal authorities into constitutional-era traditional councils with a role in traditional governance. The process involves reconstituting these councils to meet certain thresholds of women and democratically elected ...

  2. Responding to Suicidal Calls: Does Trait Anxiety Hinder or Help?

    Science.gov (United States)

    Brown, Marceline Moulin; Range, Lillian M.

    2005-01-01

    To see if trait anxiety and suicidality interfered with the ability to respond to suicidal crisis calls, 279 undergraduates completed measures of trait anxiety and suicidality in the past week, and the revised Suicide Intervention Response Inventory (SIRI-2). Unexpectedly, trait anxiety (but not suicidality) correlated with better SIRI-2 scores.…

  3. How context can help and hinder special needs students

    NARCIS (Netherlands)

    van der Steen, Steffie

    2014-01-01

    Testing is an integral part of schooling nowadays and strongly supported by public policy. However, do standardized tests of academic performance measure what they claim? This presentation focuses on two studies conducted in the domain of science and technology. We start with a cross-sectional study

  4. Do Graphical Overviews Facilitate or Hinder Comprehension in Hypertext?

    Science.gov (United States)

    Salmeron, Ladislao; Baccino, Thierry; Canas, Jose J.; Madrid, Rafael I.; Fajardo, Inmaculada

    2009-01-01

    Educational hypertexts usually include graphical overviews, conveying the structure of the text schematically with the aim of fostering comprehension. Despite the claims about their relevance, there is currently no consensus on the impact that hypertext overviews have on the reader's comprehension. In the present paper we have explored how…

  5. Factors that Hinder Parents from the Communicating of Sexual ...

    African Journals Online (AJOL)

    Parent-adolescent communication about sexual matters is one of the means that encourages adolescents to adopt responsible sexual behaviour. However, parents do not discuss sexual matters with adolescents and those who discuss to some extent; little information about sexuality is provided. This study, was, therefore ...

  6. Social Factors and Performance of Elite which Hinder Organizational Development

    Directory of Open Access Journals (Sweden)

    Vladimir Boguslavski

    2009-06-01

    Full Text Available Despite possible differences in official ideology the drawbacks of social organization and the absence of sound approach to social and personal conflicts cause constant demolition of existing formal institutions for the sake of the survival of the system. The neglect of these drawbacks brings about old problems to be transferred to the “new” state. The level of social and human capital and its proper utilization guarantees progressive development. The shifts in organizational policy is also reflected by the consequent shift in the theoretical paradigm, from treatment of a participant of the structure as an object, then as the user and finally as the client. The lack of social capital generates a vicious cycle, which brings about the necessity of object-based relations and the spread of all-pervasive protecting informality to compensate for object-based relations.

  7. Socio-cultural factors Hindering Adoption of Technologies by ...

    African Journals Online (AJOL)

    Agriculture Farmers in Enugu State, Nigeria. ... type of technologies (0s = 3.29) gender-biased land issues (0s= 3.28), institutional problems (finance and marketing) (0s = 3.78 & 3.17) among other problems constituted towards the low adoption level.

  8. Factors Hindering the Accessibility of Agricultural Credit by Farmers ...

    African Journals Online (AJOL)

    In securing credit facilities, the study also identified some problems such as; inadequate credit information, bank stringent conditions, location of lending bank and bureaucratic processes in the bank. These problems were found not to vary with agricultural zones. It is advised that farmers need to develop more cooperative ...

  9. Pain medicine and its models: helping or hindering?

    Science.gov (United States)

    Quintner, John L; Cohen, Milton L; Buchanan, David; Katz, James D; Williamson, Owen D

    2008-10-01

    To identify whether the biopsychosocial framework of illness has overcome the limitations of the biomedical model of disease when applied in the practice of pain medicine. Critical review of the literature concerning the application of biopsychosocial models to the praxis of pain medicine and the concepts of living systems. The biopsychosocial model of illness, formulated by Engel in 1977, has generated the International Association for the Study of Pain (IASP) definition of pain, two major conceptual frameworks in pain medicine, and three putative explanatory models for pain. However, in the absence of a theory that seeks to understand the lived experience of pain as an emergent and unpredictable phenomenon, these progeny of the biopsychosocial model have been caught in circular argument and have been unable to overcome biomedical reductionism or the perpetuation of body-mind dualism. In particular, the implication that pain can be a "thing" separate and distinct from the body bears little relationship to the lived experience of pain. Such marginalizing results when an observer attempts to reduce the experience of the pain of another person. The self-referentiality of living systems (through their qualities of autopoiesis, noncentrality and negentropy) sees pain "emerge" in unpredictable ways that defy any lineal reduction of the lived experience to any particular "thing." Pain therefore constitutes an aporia, a space and presence that defies us access to its secrets. We suggest a project in which pain may be apprehended in the clinical encounter, through the engagement of two autonomous self-referential beings in the intersubjective or so-called third space, from which new therapeutic possibilities can arise.

  10. Enemies at work : can they hinder your career?

    NARCIS (Netherlands)

    Moerbeek, H.H.S.; Need, A.

    2003-01-01

    This paper addresses the question to what extent foes deteriorate a person's labor market position and block persons in their labor market position. We improve upon earlier research by explicitly focusing on the negative effects of social capital. A second way to improve upon earlier findings is to

  11. Focus on ecological weed management : what is hindering adoption?

    NARCIS (Netherlands)

    Bastiaans, L.; Paolini, R.; Baumann, D.T.

    2008-01-01

    Despite increased concerns regarding the heavy reliance of many cropping systems on chemical weed control, adoption of ecological weed management practices is only steadily progressing. For this reason, this paper reflects on both the possibilities and limitations of cultural weed control practices.

  12. Novel sterically hindered cannabinoid CB1 receptor ligands.

    Science.gov (United States)

    Urbani, Paolo; Cascio, Maria Grazia; Ramunno, Anna; Bisogno, Tiziana; Saturnino, Carmela; Di Marzo, Vincenzo

    2008-08-01

    In the present study, 11 novel N-(3,3-diphenyl)propyl-2,2-diphenylacetamide derivatives (4a-d and 9a-g) and six triphenylacetamides (10a-c and 11a-c) were synthesized and tested as ligands of cannabinoid CB(1) and CB(2) receptors. All compounds exhibited affinity for CB(1) and CB(2) receptors. Four compounds (4b, 9a, 9b, and 11a) showed selectivity for CB(1) versus CB(2) receptors, although only the N-(3,3-diphenyl)propyl-2,2-diphenylacetamide (4b) can be considered a potent CB(1) ligand (K(i)=58 nM). It was 140-fold selective over CB(2) receptors (K(i)=7800 nM) and behaved as an inverse agonist by stimulating forskolin-induced cAMP formation in mouse N18TG2 neuroblastoma cells. This compound is the first of a novel class of tetraphenyl CB(1) ligands that, in view of its easy synthesis and high affinity for CB(1) receptors and despite its sterical hindrance, will be useful for the design of new blockers of this therapeutically exploitable receptor type.

  13. Fatores que favorecem e dificultam o trabalho dos enfermeiros nos serviços de atenção à saúde Factores que favorecen y dificultan el trabajo de los enfermeros en los servicios de atención a la salud Factors that favor and hinder the work of nurses in services of health attention

    Directory of Open Access Journals (Sweden)

    Carmem Lúcia Colomé Beck

    2010-09-01

    fortificar las acciones que desarrolla frente al usuario del Sistema Único de Salud y buscar soluciones delante de las necesidades de la comunidad.The nurse faces factors that favor and hinder the performance of his work and interfere with the feelings before work. This is an exploratory-descriptive study with a qualitative approach. It aimed to sociodemographically characterize the nurses of the Services of Health Attention of a town in the State of Rio Grande do Sul and to identify the factors that favor and hinder the performance of the work. The data were collected from March to July 2007 through a survey. The sample was composed by 24 nurses. The data analysis enabled two build two theme axes: factors that favor and hinder the performance of nurse work. The results suggest that nurses perceive satisfaction at work. However, it is necessary to rethink the process of work of this Professional to strength the actions before the user of Single Health System's and search for resolutivity before the necessities of the community.

  14. Citrate-stabilized gold nanoparticles hinder fibrillogenesis of a pathological variant of β2-microglobulin.

    Science.gov (United States)

    Cantarutti, Cristina; Raimondi, Sara; Brancolini, Giorgia; Corazza, Alessandra; Giorgetti, Sofia; Ballico, Maurizio; Zanini, Stefano; Palmisano, Giovanni; Bertoncin, Paolo; Marchese, Loredana; Patrizia Mangione, P; Bellotti, Vittorio; Corni, Stefano; Fogolari, Federico; Esposito, Gennaro

    2017-03-17

    Nanoparticles have repeatedly been shown to enhance fibril formation when assayed with amyloidogenic proteins. Recently, however, evidence casting some doubt about the generality of this conclusion started to emerge. Therefore, to investigate further the influence of nanoparticles on the fibrillation process, we used a naturally occurring variant of the paradigmatic amyloidogenic protein β2-microglobulin (β2m), namely D76N β2m where asparagine replaces aspartate at position 76. This variant is responsible for aggressive systemic amyloidosis. After characterizing the interaction of the variant with citrate-stabilized gold nanoparticles (Cit-AuNPs) by NMR and modeling, we analyzed the fibril formation by three different methods: thioflavin T fluorescence, native agarose gel electrophoresis and transmission electron microscopy. The NMR evidence indicated a fast-exchange interaction involving preferentially specific regions of the protein that proved, by subsequent modeling, to be consistent with a dimeric adduct interacting with Cit-AuNPs. The fibril detection assays showed that AuNPs are able to hamper D76N β2m fibrillogenesis through an effective interaction that competes with protofibril formation or recruitment. These findings open promising perspectives for the optimization of the nanoparticle surface to design tunable interactions with proteins.

  15. Increasing Costs, Competition May Hinder U.S. Position of Leadership in High Energy Physics.

    Science.gov (United States)

    1980-09-16

    powerful in explaining particle interactions at high energies. 116 APPENDIX I APPENDIX I 1962 e Proposal of current algebra , a set of relations which...Current algebra is also playing a role in estimating quark masses and other modern topics. 1963 a Argonne Zero Gradient Synchrotron (ZGS) began...STANFORU LINEAl ACc(LERAIOR CENTER SLAC, P.. .o 4349 Stanford. California 94305 February 27, 1980 Mr. J. Dexter Peach, Director Energy and Minerals

  16. Implementing Human Resources Management (HRM) within Dutch VET schools: Examining the fostering and hindering factors

    NARCIS (Netherlands)

    Runhaar, P.R.; Sanders, K.

    2013-01-01

    Vocational Education and Training (VET) Institutions face serious challenges, like the implementation of competence-based education and upcoming teacher shortages, which urge them to implement Human Resources Management policy and practices (HRM). The implementation of HRM, however, often stagnates.

  17. How Do Families Help or Hinder the Emergence of Early Executive Function?

    Science.gov (United States)

    Hughes, Claire H.; Ensor, Rosie A.

    2009-01-01

    This chapter describes longitudinal findings from a socially diverse sample of 125 British children seen at ages two and four. Four models of social influence on executive function are tested, using multiple measures of family life as well as comprehensive assessments of children's executive functions. Our results confirm the importance of…

  18. Male Primary School Teachers: Helping or Hindering a Move to Gender Equity?

    Science.gov (United States)

    Cushman, Penni

    2010-01-01

    Despite research linking dominant masculinities to the disengagement of some boys from schooling, men teachers appear to be either unaware of the related literature, or reluctant to engage in behaviours that have increased their vulnerability to accusations of sexual abuse or homosexuality. A small study of men teachers in England, Sweden and New…

  19. Prolonging life or hindering death? An Orthodox perspective on death, dying and euthanasia.

    Science.gov (United States)

    Hatzinikolaou, Nikolaos

    2003-01-01

    This article addresses death as a biological event and attempts to approach it as a mystery within the light of the Orthodox Christian theology and tradition. First, the value of the last moments of the life of a human being is analyzed; then the state of living is differentiated from the state of surviving that results, in some extreme cases, from the intrusion of technology in medicine. The article elaborates on the sacred and spiritual character of death which, when viewed within the light of the Christ's resurrection, is transformed into a great blessing. The last part of the article focuses on the newly emerged issue of euthanasia and the reasons behind it. It poses certain vital questions that ought to be answered before legalization gets on its way. Finally, the conclusion summarizes the position of the Orthodox Church of Greece on death, dying and euthanasia.

  20. Muslim Prison Ministry: Hindering the Spread of the Radical, Militant, Violent and Irreconcilable Wing of Islam

    Science.gov (United States)

    2006-05-25

    Brothers, the Muslim Brotherhood or MB) was established in 1928 by Hassan Al-Banna and claimed they wanted to attain their goals by peaceful means.57...fi al-Jihad min akhta’ (Shedding Light on Errors Committed in the Jihad) by Hamdi Abdel-Rahman, Nageh Ibrahim and Ali Al-Sherif; Hormat al-Gholw fi

  1. Thermal stratification hinders gyrotactic micro-organism rising in free-surface turbulence

    Science.gov (United States)

    Lovecchio, Salvatore; Zonta, Francesco; Marchioli, Cristian; Soldati, Alfredo

    2017-05-01

    Thermal stratification in water bodies influences the exchange of heat, momentum, and chemical species across the air-water interface by modifying the sub-surface turbulence characteristics. Turbulence modifications may in turn prevent small motile algae (phytoplankton, in particular) from reaching the heated surface. We examine how different regimes of stable thermal stratification affect the motion of these microscopic organisms (modelled as gyrotactic self-propelling cells) in a free-surface turbulent channel flow. This archetypal setup mimics an environmentally plausible situation that can be found in lakes and oceans. Results from direct numerical simulations of turbulence coupled with Lagrangian tracking reveal that rising of bottom-heavy self-propelling cells depends strongly on the strength of stratification, especially near the thermocline where high temperature and velocity gradients occur: Here hydrodynamic shear may disrupt directional cell motility and hamper near-surface accumulation. For all gyrotactic re-orientation times considered in this study (spanning two orders of magnitude), we observe a reduction of the cell rising speed and temporary confinement under the thermocline: If re-orientation is fast, cells eventually trespass the thermocline within the simulated time span; if re-orientation is slow, confinement lasts much longer because cells align in the streamwise direction and their vertical swimming is practically annihilated.

  2. Information Management in New Motherhood: Does the Internet Help or Hinder?

    Science.gov (United States)

    Barkin, Jennifer L; Jani, Smit

    2016-11-01

    Women are faced with the task of gathering information and making subsequent decisions for themselves and their families as they are often the primary caregivers. The purpose of this study was to elucidate prominent themes related to information management and Internet usage in new motherhood. While the advantages to online support have been explored, triggered anxiety has not been a focus of the literature. A focus group study of 31 adult, postpartum women was held at a large, urban medical center in the Northeastern United States. Data related to information management were extracted and analyzed thematically. Women reported experiencing (a) a forcible, internal drive for information related to family health and (b) a high level of anxiety surrounding health-related Internet searches. Health care providers must be aware that women will consult the Internet for information and that at least a portion of those individuals will experience anxiety as a result. © The Author(s) 2016.

  3. Displaced by development: How the state can hinder or help | CRDI ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    , where a series of mega developments has reshaped the city and its suburbs – and displaced many residents. In their 2015 paper “Changing Cities and Changing Lives: Development Induced Displacement in Kochi, Kerala”, ...

  4. Family relationships and advance care planning: do supportive and critical relations encourage or hinder planning?

    Science.gov (United States)

    Boerner, Kathrin; Carr, Deborah; Moorman, Sara

    2013-03-01

    The effectiveness of advance care planning (ACP) may depend on family members' understanding of patient preferences. However, we know of no studies that explore the association between family relationship dynamics and ACP. ACP includes a living will, durable power of attorney for health care (DPAHC) appointment, and discussions. We evaluated the effects of three aspects of family relations--general family functioning, support and criticism from spouse, and support and criticism from children--on both overall ACP and specific DPAHC designations. Using multinomial logistic regression models and data from a sample of 293 older adults, we estimated the effects of family relationship quality on the likelihood of completing ACP and appointing a spouse or adult child as DPAHC. Analyses controlled for demographic and health characteristics. Better overall family functioning increased the odds of ACP. Higher levels of spousal support increased the odds of holding informal discussions, whereas spousal criticism reduced the odds of naming one's spouse as DPAHC. Both criticism and emotional support from children increased the odds that a child was named as DPAHC. Family dynamics affect ACP in complex ways and should be considered when patients and their families discuss end-of-life care and make DPAHC designations.

  5. Factors That Facilitate Or Hinder Fuel-Saving Initiatives and Technology

    Science.gov (United States)

    2015-12-01

    interviewees 27 believed that outstanding service and high levels of customer satisfaction were another critical factor of FedEx’s success. They...solution to supply chain issues, and it leverages them to develop fuel-savings efficiencies (FedEx Corporation, 2015). FedEx refers to its network of...implement quick 2 changes or to accommodate for fluctuations in a potentially volatile oil market. Time, resources, and devotion are required to

  6. Coping Strategies to Hinder Intention to Leave in Iranian Nurses: A Qualitative Content Analysis

    Directory of Open Access Journals (Sweden)

    Leila Valizadeh

    2015-10-01

    Full Text Available Background: Due to the high clinical challenges, differences in coping strategies, and high workload in nurses, there is a need to develop strategies to keep them in the profession. The aim of the present study was to explore the Iranian nurses’ coping strategies to deal with intention to leave. Methods: A qualitative content analysis was used to obtain rich data. We performed 13 in-depth face-to-face semi-structured interviews with nurses working in hospitals affiliated to Tabriz and Urmia Universities of Medical Sciences in Iran, selected through purposive sampling. Constant comparative method was used for data analysis. Results: Three categories and eleven subcategories emerged during data analysis. The extracted categories and sub-categories consisted of (I Self-empowerment (practical knowledge increase, responsibility, finding identification of the nurse, balancing work and life, seek support and humanitarian interests, (II Self-controlling (tolerance, avoidance, the routine-based performance, and (III Pursuing opportunities for advancement and promotion (community development, planning for higher education. Conclusion: Nurses make attempts to individually manage problems and stressors perceived from bedside that have led them to leave the bedside; these efforts have been effective in some cases but sometimes they are ineffective due to discontinuous training and relative competence in terms of how to manage and deal with problems. It is suggested that nurses should learn strategies scientifically to meet the challenges of bedside. Through enabling and supporting behaviors and creating opportunities for growth and professional development, nursery managers can help nurses to stay and achieve improvement of the quality of cares.

  7. Does Paid Employment Help or Hinder Performance in Secondary School? Insights from US High School Students.

    Science.gov (United States)

    Stern, David; Briggs, Derek

    2001-01-01

    Previous research shows that secondary students with moderate working hours perform better academically than those with no work or longer hours. Essays by working students reveal that many value both school and work as preparation for the future. These attitudes may explain why working does not detract from their school performance. (Contains 22…

  8. Imaging Hindered Rotations of Alkoxy Species on TiO2(110)

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zhenrong; Rousseau, Roger J.; Gong, Jinlong; Kay, Bruce D.; Dohnalek, Zdenek

    2009-12-16

    We present the first study of the rotational dynamics of organic species on any oxide surface. Specifically, variable-temperature scanning tunneling microscopy (STM) and dispersion-corrected density functional theory are used to study the alkyl chain conformational disorder and dynamics of 1-, 2-, 3- and 4-octoxy on rutile TiO2(110). Initially, the geminate pairs of the octoxy and bridging hydroxyl species are created via octanol dissociation on bridging-oxygen (Ob) vacancy defects. The STM images provide time averaged snapshots of octoxy species rotating among multiple energetically nearly-degenerate configurations accessible at a given temperature. In the calculations we find that the underlying corrugated potential energy surface is a result of the interplay between attractive Van der Waals dispersion forces leading to weak attractive C...Ti and repulsive C...Ob interactions which lead to large barriers of 50-70kJmol-1 for the rotation of the octoxy alkyl chains across the Ob rows. In the presence of the germinal hydroxyl groups we find that the relative populations of the various conformations as well as the rotational barriers are perturbed by the presence of geminate hydroxyl due to additional C...hydroxyl repulsions.

  9. From Mammy to Superwoman: Images that Hinder Black Women's Career Development

    Science.gov (United States)

    Reynolds-Dobbs, Wendy; Thomas, Kecia M.; Harrison, Matthew S.

    2008-01-01

    Black women, like other women of color, find themselves at the intersection of both racism and sexism in the workplace. Due to their unique dual status as racial and gender minorities, they encounter unique and unexplored barriers that inhibit their career as well as leadership development. The goal of this article is to highlight the emerging…

  10. Coaching individuals with perfectionistic tendencies When high standards help and hinder

    Directory of Open Access Journals (Sweden)

    Sarah Corrie

    2014-07-01

    Full Text Available Perfectionism has been widely recognised in the clinical field but has received less attention in the coaching psychology literature. Referring to overly high and unforgiving personal standards of performance that are accompanied by harsh self-evaluation when self-imposed standards are not met, perfectionism has the potential to undermine the coachee’s ability to achieve their goals as well as the coaching process itself. In consequence, it is important for practitioners to be able to identify and work effectively with those coachees whose perfectionistic tendencies represent an obstacle to progress. This paper discusses the current literature on perfectionism and provides recommendations on how to work effectively with coachees for whom unremittingly high personal standards are an impediment to personal growth and development.

  11. Does infrastructure provision hinder energy integration? The case of natural gas in the southern cone

    Energy Technology Data Exchange (ETDEWEB)

    Navajas, Fernando

    2010-09-15

    This paper uses evidence on policies, markets and private transactions to discuss the experience of natural gas infrastructure integration in the Southern Cone of Latin America. The argument is that contracts on international exchanges supported by infrastructure may become incomplete due to contingencies related to policy-induced price distortions not anticipated at the moment of writing. Beyond regulatory risk mitigation, it calls for back-up contract provisions designed to cope with aggregate imbalances and for some supranational coordination related to information about market conditions and on energy planning dialogues that test consistency and stress situations in markets where exports originate.

  12. How Hepatitis D Virus Can Hinder the Control of Hepatitis B Virus

    NARCIS (Netherlands)

    Xiridiou, M.; Borkent-Raven, B.; Hulshof, J.; Wallinga, J.

    2009-01-01

    Background: Hepatitis D (or hepatitis delta) virus is a defective virus that relies on hepatitis B virus (HBV) for transmission; infection with hepatitis D can occur only as coinfection with HBV or superinfection of an existing HBV infection. Because of the bond between the two viruses, control

  13. How Hepatitis D Virus Can Hinder the Control of Hepatitis B Virus

    OpenAIRE

    Maria Xiridou; Barbara Borkent-Raven; Joost Hulshof; Jacco Wallinga

    2009-01-01

    BACKGROUND: Hepatitis D (or hepatitis delta) virus is a defective virus that relies on hepatitis B virus (HBV) for transmission; infection with hepatitis D can occur only as coinfection with HBV or superinfection of an existing HBV infection. Because of the bond between the two viruses, control measures for HBV may have also affected the spread of hepatitis D, as evidenced by the decline of hepatitis D in recent years. Since the presence of hepatitis D is associated with suppressed HBV replic...

  14. Beauty Hinders Attention Switch in Change Detection: The Role of Facial Attractiveness and Distinctiveness

    Science.gov (United States)

    Chen, Wenfeng; Liu, Chang Hong; Nakabayashi, Kazuyo

    2012-01-01

    Background Recent research has shown that the presence of a task-irrelevant attractive face can induce a transient diversion of attention from a perceptual task that requires covert deployment of attention to one of the two locations. However, it is not known whether this spontaneous appraisal for facial beauty also modulates attention in change detection among multiple locations, where a slower, and more controlled search process is simultaneously affected by the magnitude of a change and the facial distinctiveness. Using the flicker paradigm, this study examines how spontaneous appraisal for facial beauty affects the detection of identity change among multiple faces. Methodology/Principal Findings Participants viewed a display consisting of two alternating frames of four faces separated by a blank frame. In half of the trials, one of the faces (target face) changed to a different person. The task of the participant was to indicate whether a change of face identity had occurred. The results showed that (1) observers were less efficient at detecting identity change among multiple attractive faces relative to unattractive faces when the target and distractor faces were not highly distinctive from one another; and (2) it is difficult to detect a change if the new face is similar to the old. Conclusions/Significance The findings suggest that attractive faces may interfere with the attention-switch process in change detection. The results also show that attention in change detection was strongly modulated by physical similarity between the alternating faces. Although facial beauty is a powerful stimulus that has well-demonstrated priority, its influence on change detection is easily superseded by low-level image similarity. The visual system appears to take a different approach to facial beauty when a task requires resource-demanding feature comparisons. PMID:22393457

  15. Rebuilding Iraq: Reconstruction Progress Hindered by Contracting, Security, and Capacity Challenges

    National Research Council Canada - National Science Library

    Walker, David M

    2007-01-01

    The Department of Defense (DoD) has relied extensively on contractors to undertake major reconstruction projects and provide support to its deployed forces, but these efforts have not always achieved desired outcomes...

  16. Hindering effects in diffusion of CO2/CH4 mixtures in ZIF-8 crystals

    NARCIS (Netherlands)

    Chmelik, C.; van Baten, J.; Krishna, R.

    2012-01-01

    Cage-type micro-porous materials such as LTA, CHA, SAPO-34, DDR, ERI, ZIF-7, and ZIF-8 have significant potential for use in membrane technologies for CO2 capture. The permeation selectivities are governed by a combination of adsorption and diffusion selectivities, each of which can be separately

  17. Within-host bacterial diversity hinders accurate reconstruction of transmission networks from genomic distance data.

    Science.gov (United States)

    Worby, Colin J; Lipsitch, Marc; Hanage, William P

    2014-03-01

    The prospect of using whole genome sequence data to investigate bacterial disease outbreaks has been keenly anticipated in many quarters, and the large-scale collection and sequencing of isolates from cases is becoming increasingly feasible. While sequence data can provide many important insights into disease spread and pathogen adaptation, it remains unclear how successfully they may be used to estimate individual routes of transmission. Several studies have attempted to reconstruct transmission routes using genomic data; however, these have typically relied upon restrictive assumptions, such as a shared topology of the phylogenetic tree and a lack of within-host diversity. In this study, we investigated the potential for bacterial genomic data to inform transmission network reconstruction. We used simulation models to investigate the origins, persistence and onward transmission of genetic diversity, and examined the impact of such diversity on our estimation of the epidemiological relationship between carriers. We used a flexible distance-based metric to provide a weighted transmission network, and used receiver-operating characteristic (ROC) curves and network entropy to assess the accuracy and uncertainty of the inferred structure. Our results suggest that sequencing a single isolate from each case is inadequate in the presence of within-host diversity, and is likely to result in misleading interpretations of transmission dynamics--under many plausible conditions, this may be little better than selecting transmission links at random. Sampling more frequently improves accuracy, but much uncertainty remains, even if all genotypes are observed. While it is possible to discriminate between clusters of carriers, individual transmission routes cannot be resolved by sequence data alone. Our study demonstrates that bacterial genomic distance data alone provide only limited information on person-to-person transmission dynamics.

  18. Displaced by development: How the state can hinder or help | IDRC ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2016-11-16

    , where a series of mega developments has reshaped the city and its suburbs – and displaced many residents. In their 2015 paper “Changing Cities and Changing Lives: Development Induced Displacement in Kochi, Kerala”, ...

  19. How Approaches to Stuck-in-the-Mud School Funding Hinder Improvement

    Science.gov (United States)

    Lazarín, Melissa

    2013-01-01

    Many state and education leaders continue to support and employ methods that prevent schools and principals from undertaking the efforts that they think are most needed to improve education in their classrooms. The use of state categorical grants--funds to school districts with strict limits on their use--exemplifies this lack of innovation in…

  20. Aneurysmal bone cyst does not hinder the success of kidney transplantation. A case report.

    Science.gov (United States)

    Giordano, Mario; Caloro, Giorgia; Gaeta, Alberto; Vergori, Antonio; Santangelo, Luisa; Giordano, Paolo; Ruggieri, Pietro

    2015-03-01

    Uremic osteodystrophy is an expected complication in subjects with chronic renal insufficiency. It develops gradually and progressively already during the conservative treatment and then during the dialysis treatment. It can present a wide histopathological spectrum including typical alterations (from osteitis fibrosa to osteomalacia and/or mixed lesions) or, more rarely, isolated bone lesions indicative of a brown tumor of the bone. These conditions must be clearly identified in the pretransplant phase, especially if a bone lesion indicative of a pathological condition possibly evolving into a neoplasm is detected fortuitously. We report the case of a 19-yr-old boy with renal insufficiency and candidate for a pre-emptive renal transplantation from a living donor, in whom the diagnosis of ABC of the pubic symphysis - asymptomatic and fortuitously detected while performing instrumental investigations - was suspected through the imaging studies (CT scan, MRI) and was confirmed by the histological examination. This made it possible to perform the renal transplant. The immunosuppressive treatment, which was subsequently administered, was based on steroids, calcineurin inhibitors (tacrolimus), and mycophenolate and did not determine any modification in the radiological aspect of the bone lesion, even after more than one yr from the transplant. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. An Investigation of the Factors Hindering Adults' Participation in Physical Activity

    Science.gov (United States)

    Dinç, Zeynep Filiz

    2017-01-01

    This study focuses on the non-participation of adults in physical activity and the reasons that have been preventing them to participate. The study is carried out with 283 participants (116 men and 167 women) who live in Adana, Turkey. Their ages range from 18-66. The average age of the adult participants is 31.81 ± 10.12. The demographical…

  2. Globalization of authorship in the marketing discipline : Does it help or hinder the field?

    NARCIS (Netherlands)

    Stremersch, S; Verhoef, PC

    2005-01-01

    Marketing scholars have reflected upon the marketing discipline's internal evolution before. However, no prior study has assessed the globalization of authorship in our discipline, let alone assessed its consequences for the field. This paper addresses the following two questions: (1) Is there

  3. The 'grass ceiling': limitations in the literature hinder our understanding of cannabis use and its consequences.

    Science.gov (United States)

    Temple, Elizabeth C; Brown, Rhonda F; Hine, Donald W

    2011-02-01

    To illustrate how limitations in the cannabis literature undermine our ability to understand cannabis-related harms and problems experienced by users and identify users at increased risk of experiencing adverse outcomes of use. Limitations have been organized into three overarching themes. The first relates to the classification systems employed by researchers to categorize cannabis users, their cannabis use and the assumptions on which these systems are based. The second theme encompasses methodological and reporting issues, including differences between studies, inadequate statistical control of potential confounders, the under-reporting of effect sizes and the lack of consideration of clinical significance. The final theme covers differing approaches to studying cannabis use, including recruitment methods. Limitations related to the nature of the data collected by researchers are discussed throughout, with a focus on how they affect our understanding of cannabis use and users. These limitations must be addressed to facilitate the development of effective and appropriately targeted evidence-based public health campaigns, treatment programmes and preventative, early intervention and harm minimization strategies, and to inform cannabis-related policy and legislation. © 2010 The Authors, Addiction © 2010 Society for the Study of Addiction.

  4. Values in organizations as factors that promote or hinder socioeconomic convergence / Rebekka Vedina

    Index Scriptorium Estoniae

    Vedina, Rebekka, 1976-

    2002-01-01

    Bibliogr. lk. 141-142. - Kokkuvõte eesti k. lk. 143. Ülevaade, millised väärtused organisatsioonides soodustavad ja millised takistavad konvergentsi ning millist osa selles täidavad rahvuskultuuri väärtused

  5. The shadows of the socialist past: Lack of self-reliance hinders entrepreneurship

    National Research Council Canada - National Science Library

    Bauernschuster, Stefan; Falck, Oliver; Gold, Robert; Heblich, Stephan

    2012-01-01

    .... Since East Germany adopted the formal institutions of a market economy quasi overnight when reunifying with West Germany, we avoid simultaneity issues regarding current institutions and preferences...

  6. Common contaminants in next-generation sequencing that hinder discovery of low-abundance microbes.

    Directory of Open Access Journals (Sweden)

    Martin Laurence

    Full Text Available Unbiased high-throughput sequencing of whole metagenome shotgun DNA libraries is a promising new approach to identifying microbes in clinical specimens, which, unlike other techniques, is not limited to known sequences. Unlike most sequencing applications, it is highly sensitive to laboratory contaminants as these will appear to originate from the clinical specimens. To assess the extent and diversity of sequence contaminants, we aligned 57 "1000 Genomes Project" sequencing runs from six centers against the four largest NCBI BLAST databases, detecting reads of diverse contaminant species in all runs and identifying the most common of these contaminant genera (Bradyrhizobium in assembled genomes from the NCBI Genome database. Many of these microorganisms have been reported as contaminants of ultrapure water systems. Studies aiming to identify novel microbes in clinical specimens will greatly benefit from not only preventive measures such as extensive UV irradiation of water and cross-validation using independent techniques, but also a concerted effort to sequence the complete genomes of common contaminants so that they may be subtracted computationally.

  7. Hindering and buffering factors for parental sleep in neonatal care. A phenomenographic study.

    Science.gov (United States)

    Edéll-Gustafsson, Ulla; Angelhoff, Charlotte; Johnsson, Ewa; Karlsson, Jenny; Mörelius, Evalotte

    2015-03-01

    To explore and describe how parents of preterm and/or sick infants in neonatal care perceive their sleep. Parents experience many stressful situations when their newborn infant is preterm and/or sick. This affects bonding. By developing more family-centred care units with single-family rooms, parents are given the opportunity to stay and care for their newborn infant(s) 24 hours a day. Lack of sleep may affect new parents' ability to cope with the many challenges they face on a daily basis. A phenomenographic study with an inductive and exploratory design. Semi-structured interviews were conducted with twelve parents of infants in neonatal care between January-March 2012. To describe variations in perception of the phenomenon, data were analysed using phenomenography. Four descriptive categories were identified within the phenomenon sleep in parents of preterm and/or sick infants in neonatal care: impact of stress on sleep; how the environment affects sleep; keeping the family together improves sleep; and, how parents manage and prevent tiredness. Anxiety, uncertainty and powerlessness have a negative influence on sleep. This can be decreased by continuous information, guidance and practical support. Skin-to-skin care was perceived as a stress-reducing factor that improved relaxation and sleep and should be encouraged by the nurse. The parents also mentioned the importance of being together. Having a private place where they could relax and take care of themselves and their newborn infant improved sleep. It was also desirable to involve older siblings in order to decrease feelings of loneliness, sadness and isolation. Improved parental sleep in neonatal care may help the families cope with the situation and facilitate problem-solving, emotional regulation and the transition to parenthood. © 2014 John Wiley & Sons Ltd.

  8. Intersensory Redundancy Hinders Face Discrimination in Preschool Children: Evidence for Visual Facilitation

    Science.gov (United States)

    Bahrick, Lorraine E.; Krogh-Jespersen, Sheila; Argumosa, Melissa A.; Lopez, Hassel

    2014-01-01

    Although infants and children show impressive face-processing skills, little research has focused on the conditions that facilitate versus impair face perception. According to the intersensory redundancy hypothesis (IRH), face discrimination, which relies on detection of visual featural information, should be impaired in the context of…

  9. Comparing Strategies for Health Information Dissemination: Messengers That Can Help or Hinder.

    Science.gov (United States)

    Fishman, Jessica; Greenberg, Patricia; Bagga, Margy Barbieri; Casarett, David; Propert, Kathleen

    2017-01-01

    To test the effects of different messengers on the dissemination of health information. An experimental study exposed participants to 12 news articles pertaining to 1 of 3 health topics framed from the perspective of 4 generic messengers: religious figures, doctors, celebrity patients, or ordinary patients. Participants select as many of the 12 articles as desired. A cancer clinic within a large, urban hospital serving a sociodemographically diverse patient population. Eighty-nine patients with a history of cancer. The primary outcome was the frequency with which each news story was selected. Summary statistics and a general estimating equation model. For each health topic, news articles using celebrity messengers were the least likely to be selected; almost half of the participants (36 [41.4%] of 87) rejected all such articles. Articles linked to religious figures were equally unpopular ( P = .59). Articles that used doctors or ordinary patients as the messenger were very likely to be selected: Nearly all women (84 [96.6%] of 87) selected at least one of these. Furthermore, the odds of choosing articles linked to celebrities or religious leaders were statistically significantly lower than the odds of choosing those linked to ordinary patients or doctors ( P celebrities or religious figures were consistently less likely to be selected than those linked to ordinary patients, or doctors.

  10. The Trouble With Tailings: How Alteration Mineralogy can Hinder Quantitative Phase Analysis of Mineral Waste

    Science.gov (United States)

    Wilson, S. A.; Mills, S. J.; Dipple, G. M.; Raudsepp, M.

    2009-05-01

    Quantitative phase analysis, using the Rietveld method and X-ray powder-diffraction data, has become a standard technique for analysis of mineral waste from mining operations. This method relies upon the availability of well defined crystal structures for all detectable mineral phases in a sample. An even more basic assumption, central to quantitative mineralogy, is that all significant mineral phases can be detected from X-ray diffraction data. This is not always the case, because X-ray amorphous and nanocrystalline mineral phases can develop within geological samples as a result of chemical weathering. The extent of mineral-water interaction to which mine tailings are exposed, during processing and storage, makes these materials particularly susceptible to weathering and alteration. We have used the Rietveld method and X-ray powder-diffraction data to quantify the uptake of atmospheric CO2 into secondary carbonate minerals at two operating mines: the Diavik Diamond Mine, Northwest Territories, Canada, and the Mount Keith Nickel Mine, Western Australia, Australia. At Diavik, nominally anhydrous minerals in kimberlitic mine tailings have been found to contain X-ray amorphous material and hydroxyl groups detectable by Raman spectroscopy. A series of weighed mixtures, prepared to simulate kimberlite mine tailings, has been used to assess the effects of X-ray amorphous material on quantitative phase analysis of Diavik tailings. At Mount Keith, hydrated sulphate minerals and halide minerals develop efflorescent crusts at the surface of the tailings storage facility. Hydrated sulphate minerals in these mine tailings commonly decompose to amorphous substances rather than dehydrating to produce minerals detectable from X-ray powder-diffraction patterns. Nanocrystalline and X-ray amorphous material in mine tailings can affect the accuracy of quantitative determinations of CO2 trapping and abundances of sulphur-bearing minerals associated with redox reactions. Here we assess the impact of amorphous material on quantitative X-ray diffraction results with particular reference to CO2 sequestration and suggest strategies for detection and analysis.

  11. High solar radiation hinders tree regeneration above the alpine treeline in northern Ecuador

    NARCIS (Netherlands)

    Bader, M.; Geloof, van I.; Rietkerk, M.

    2007-01-01

    Many tropical alpine treelines lie below their climatic potential, because of natural or anthropogenic causes. Forest extension above the treeline depends on the ability of trees to establish in the alpine environment. This ability may be limited by different factors, such as low temperatures,

  12. High solar radiation hinders tree regeneration above the alpine treeline in northern Ecuador

    NARCIS (Netherlands)

    Bader, M.Y.; Geloof, I. van; Rietkerk, M.G.

    2007-01-01

    Many tropical alpine treelines lie below their climatic potential, because of natural or anthropogenic causes. Forest extension above the treeline depends on the ability of trees to establish in the alpine environment. This ability may be limited by different factors, such as low

  13. Traveling Companions Add Complexity and Hinder Performance in the Spatial Behavior of Rats

    DEFF Research Database (Denmark)

    Dorfman, Alex; Nielbo, Kristoffer Laigaard; Eilam, David

    2016-01-01

    set of objects in each trip with one of them leading. Whether alone or with a partner, rats continued to revisit the same objects; however, more such revisits occurred with a partner. We argue that revisiting objects is not necessarily an error, since returning to past places is an important aspect...... and feeding in groups is a way of poison avoidance in wild rats. Finally, the addition of a social component added complexity to the environment since the rats organized their spatial behavior in reference to one another in addition to their organization in the physical surrounding. Consequently, when tested...

  14. The Englishnization of Business: Does This Help or Hinder Teaching Global Business?

    Science.gov (United States)

    Cavaliere, Frank J.; Glasscock, Kip; Sen, Kabir C.

    2014-01-01

    Globalization has been one of the most important movements in business since the end of World War II. The business education establishment, as represented by the AACSB accreditation agency, has been struggling to get its member schools to properly prepare their graduates for this new global business environment. It has generally been conceded that…

  15. The Disability Discrimination Act in the UK: helping or hindering employment among the disabled?

    Science.gov (United States)

    Bell, David; Heitmueller, Axel

    2009-03-01

    The enactment of the Americans with Disabilities Act (ADA) in 1990 triggered a substantial academic debate about its consequences on employment rates of disabled people. In contrast, the employment provision of the 1996 Disability Discrimination Act (DDA) in Britain has received little attention. Exploiting both pooled and longitudinal data, this paper provides robust evidence that, similar to the ADA in the USA, the DDA has had no impact on the employment rate of disabled people or possibly worsened it. Possible reasons for this are higher uncertainty around litigation costs, low levels of general awareness about the Act among disabled people and employers, and a lack of financial support.

  16. Some Factors Hindering Acceptance of Three Gamification Solutions in Motivation Systems, in Small and Medium Enterprises

    Directory of Open Access Journals (Sweden)

    Jacek WOŹNIAK

    2017-12-01

    Full Text Available Gamification, understood as a use of chosen game mechanisms for motivating actors in non-game contexts, is increasingly popular and has become one of the “hot topics” of managerial practice and science. Despite its widespread use in HRM, several barriers preventing its progress in certain types of organizations have been identified. Small and medium enterprises (SMEs, where employees are not accustomed to formal procedures are a specific example, as gamification is based on formal procedures. The goal of the text is to analyze employees’ opinions concerning the incorporation of chosen gaming mechanisms into their motivation systems, to check if not being accustomed to formal procedures is a barrier. Beside “typical” SMEs where the entrepreneur is present, direct relations within a team are also characteristic of company departments which achieve their goals almost without contact with the rest of the organization – as in the case of a discount stores chain. The study bases on two samples to check if being accustomed to formal procedures in the small team facilitates acceptance of gamification. Two questionnaires (one on a sample of 100 employees of a discount store chain, and the second on 73 “typical” SME employees asked respondents to declare their preferences for different types of rewards in motivation systems, including readiness to be involved in two gamification-type solutions: based on (i lotteries, or (ii BLAP gaming with non-material and material prizes. The effects of chosen factors: psychological (risk aversion and situational (dissatisfaction with current incentive system on the perception of two different ways of incorporating gamification into motivational systems, were analyzed. The results show that dissatisfaction with the current incentive system and not being risk-averse favor accepting the incorporation of gamification solutions into motivational systems. The responses of discount store employees and SME employees were similar to each other.

  17. Sterically Hindered Square-Planar Nickel(II) Organometallic Complexes: Preparation, Characterization, and Substitution Behavior

    Science.gov (United States)

    Martinez, Manuel; Muller, Guillermo; Rocamora, Merce; Rodriguez, Carlos

    2007-01-01

    The series of experiments proposed for advanced undergraduate students deal with both standard organometallic preparative methods in dry anaerobic conditions and with a kinetic study of the mechanisms operating in the substitution of square-planar complexes. The preparation of organometallic compounds is carried out by transmetallation or…

  18. Nursing curriculums may hinder a career in gerontological nursing: An integrative review.

    Science.gov (United States)

    Garbrah, William; Välimäki, Tarja; Palovaara, Marjo; Kankkunen, Päivi

    2017-09-01

    To investigate what prevents undergraduate nursing students from choosing gerontological nursing as a career option. This study utilised an integrative literature review, which allows the inclusion of previous studies with diverse research designs to gain a broader view of the reasons why nursing students do not choose a gerontological nursing career. An electronic database search of CINAHL (Ebsco), Scopus and Eric elicited 251 scientific peer-reviewed empirical studies, published from 2006 to March 2016 in English. After meeting the inclusion criteria, 97 qualified for closer examination. Following exclusion, the final analysis and synthesis included 21 articles. Four main themes described nursing students' contributing reasons for not selecting gerontological nursing as a career option: socio-demographic factors; experiences, perceptions and knowledge about ageing; perceptions concerning the nature or status of gerontological nursing; and theoretical studies and practical education of nursing curriculum. Lack of positive experiences with older people before and during nursing students' studies led to their disinterest in gerontological nursing as a career option. The nursing curriculum also reinforces the perception of modern nursing as technical, with more emphasis on acute and critical care. The findings emphasise the need to implement an age-friendly curriculum and have nurses that specialise in gerontology to serve as mentors and role models. It is important to assist nursing students in identifying the potentials for career advancement in terms of gerontological nursing. There is also a need for nursing faculties to liaise with other stakeholders to develop or improve upon the clinical atmosphere for nursing students during gerontological nursing placement. Nursing faculties must review their curriculum to ensure that there is sufficient focus on the needs of older people within the curriculum for every student. Furthermore, respected role models who are knowledgeable and enthusiastic about issues related to older people must teach gerontological nursing courses. © 2017 John Wiley & Sons Ltd.

  19. Does hydrotherapy help or hinder adaptation to training in competitive cyclists?

    Science.gov (United States)

    Halson, Shona L; Bartram, Jason; West, Nicholas; Stephens, Jessica; Argus, Christos K; Driller, Matthew W; Sargent, Charli; Lastella, Michele; Hopkins, Will G; Martin, David T

    2014-08-01

    Cold water immersion (CWI) may be beneficial for acute recovery from exercise, but it may impair long-term performance by attenuating the stimuli responsible for adaptation to training. We compared effects of CWI and passive rest on cycling performance during a simulated cycling grand tour. Thirty-four male endurance-trained competitive cyclists were randomized to CWI for four times per week for 15 min at 15°C or control (passive recovery) groups for 7 d of baseline training, 21 d of intensified training, and an 11-d taper. Criteria for completion of training and testing were satisfied by 10 cyclists in the CWI group (maximal aerobic power, 5.13 ± 0.21 W·kg; mean ± SD) and 11 in the control group (5.01 ± 0.41 W·kg). Each week, cyclists completed a high-intensity interval cycling test and two 4-min bouts separated by 30 min. CWI was performed four times per week for 15 min at 15°C. Between baseline and taper, cyclists in the CWI group had an unclear change in overall 4-min power relative to control (2.7% ± 5.7%), although mean power in the second effort relative to the first was likely higher for the CWI group relative to control (3.0% ± 3.8%). The change in 1-s maximum mean sprint power in the CWI group was likely beneficial compared with control (4.4% ± 4.2%). Differences between groups for the 10-min time trial were unclear (-0.4% ± 4.3%). Although some effects of CWI on performance were unclear, data from this study do not support recent speculation that CWI is detrimental to performance after increased training load in competitive cyclists.

  20. Baseline requirements can hinder trades in water quality trading programs: Evidence from the Conestoga watershed.

    Science.gov (United States)

    Ghosh, Gaurav; Ribaudo, Marc; Shortle, James

    2011-08-01

    The U.S. Environmental Protection Agency (USEPA) and the U.S. Department of Agriculture (USDA) are promoting point/nonpoint trading as a way of reducing the costs of meeting water quality goals. Farms can create offsets by implementing management practices such as conservation tillage, nutrient management and buffer strips. To be eligible to sell offsets or credits, farmers must first comply with baseline requirements. USEPA guidance recommends that the baseline for nonpoint sources be management practices that are consistent with the water quality goal. A farmer would not be able to create offsets until the minimum practice standards are met. An alternative baseline is those practices being implemented at the time the trading program starts, or when the farmer enters the program. The selection of the baseline affects the efficiency and equity of the trading program. It has major implications for which farmers benefit from trading, the cost of nonpoint source offsets, and ultimately the number of offsets that nonpoint sources can sell to regulated point sources. We use a simple model of the average profit-maximizing dairy farmer operating in the Conestoga watershed in Pennsylvania to evaluate the implications of baseline requirements on the cost and quantity of offsets that can be produced for sale in a water quality trading market, and which farmers benefit most from trading. Published by Elsevier Ltd.

  1. Hindered diffusion of coal liquids. Quarterly report No. 10, December 18, 1994--March 17, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Tsotsis, T.T.; Sahimi, M. [University of Southern California, Los Angeles, CA (United States). Dept. of Chemical Engineering; Webster, I.A. [UNOCAL Corp., Los Angeles, CA (United States)

    1995-09-01

    The design of industrial catalysts requires that the diffusivity of the reacting species within the catalyst be accurately known. Nowhere is this more important than in the area of coal liquefaction and upgrading of coal liquids. In this area one is faced with the task of processing a number of heavy oils, containing metals and other contaminants, in a variety of process dependent solvents. It is important, therefore, on the basis of predicting catalyst activity, selectivity, and optimizing reactor performance, that the diffusivities of these oil species be accurately known. Throughout the experimental runs we will utilize a high pressure, high temperature diffusion of cell system. This diffusion system has been tested through the measurement of the diffusivity of a number of model coal liquids. The following were accomplished this quarter: During this quarter, we have initiated a series of transport investigations under high temperature (360{degrees}) high pressure (500 psi, H{sub 2}) reactive conditions. We have also continued our studies of formation and precipitation of fractal molecular aggregates in porous media. Small-angle scattering as well as precipitation data are analyzed to delineate the structure of the molecular colloidal aggregates that are formed, when a fluid is injected into the pore space of a porous medium to react with, or displace the in-place fluid. The results suggest that these colloidal structures are diffusion-limited particle and cluster aggregates. This is the first conclusive evidence for fractality of such molecular aggregates, which has important implications for their stability and molecular weight distribution, as well as modelling their flow and precipitation in a porous medium.

  2. Does Scored VET in Schools Help or Hinder Access to Higher Education in Victoria?

    Science.gov (United States)

    Polidano, Cain; Tabasso, Domenico; Zhang, Rong

    2014-01-01

    Despite comprising only a small fraction of all vocational education and training (VET) in Schools enrolments, programs that count towards both national VET qualifications and university entry potentially fill an important role in the upper-secondary school curriculum. The aim of this study is to take a first step in gaining an understanding of…

  3. Reverse transendothelial cell migration in inflammation: to help or to hinder?

    Science.gov (United States)

    Burn, Thomas; Alvarez, Jorge Ivan

    2017-05-01

    The endothelium provides a strong barrier separating circulating blood from tissue. It also provides a significant challenge for immune cells in the bloodstream to access potential sites of infection. To mount an effective immune response, leukocytes traverse the endothelial layer in a process known as transendothelial migration. Decades of work have allowed dissection of the mechanisms through which immune cells gain access into peripheral tissues, and subsequently to inflammatory foci. However, an often under-appreciated or potentially ignored question is whether transmigrated leukocytes can leave these inflammatory sites, and perhaps even return across the endothelium and re-enter circulation. Although evidence has existed to support "reverse" transendothelial migration for a number of years, it is only recently that mechanisms associated with this process have been described. Here we review the evidence that supports both reverse transendothelial migration and reverse interstitial migration within tissues, with particular emphasis on some of the more recent studies that finally hint at potential mechanisms. Additionally, we postulate the biological significance of retrograde migration, and whether it serves as an additional mechanism to limit pathology, or provides a basis for the dissemination of systemic inflammation.

  4. Aligned Incentives: Could the Army’s Award System Inadvertently be Hindering Counterinsurgency Operations

    Science.gov (United States)

    2009-06-01

    proficiency tests prescribed by the US Army Infantry Center Pathfinder Badge 1944 Completion of the Pathfinder course conducted by the US Army Infantry...7 1 1 Bsm 1 0 Oct-05 0 0 0 Carter Lisa 1 4 0 0 Bsm 0 0 May-03 0 0 0 121 Last Name First Name A r m y A i r F o r c e N

  5. Neighing, barking, and drumming horses-object related sounds help and hinder picture naming.

    Science.gov (United States)

    Mädebach, Andreas; Wöhner, Stefan; Kieseler, Marie-Luise; Jescheniak, Jörg D

    2017-09-01

    The study presented here investigated how environmental sounds influence picture naming. In a series of four experiments participants named pictures (e.g., the picture of a horse) while hearing task-irrelevant sounds (e.g., neighing, barking, or drumming). Experiments 1 and 2 established two findings, facilitation from congruent sounds (e.g., picture: horse, sound: neighing) and interference from semantically related sounds (e.g., sound: barking), both relative to unrelated sounds (e.g., sound: drumming). Experiment 3 replicated the effects in a situation in which participants were not familiarized with the sounds prior to the experiment. Experiment 4 replicated the congruency facilitation effect, but showed that semantic interference was not obtained with distractor sounds which were not associated with target pictures (i.e., were not part of the response set). The general pattern of facilitation from congruent sound distractors and interference from semantically related sound distractors resembles the pattern commonly observed with distractor words. This parallelism suggests that the underlying processes are not specific to either distractor words or distractor sounds but instead reflect general aspects of semantic-lexical selection in language production. The results indicate that language production theories need to include a competitive selection mechanism at either the lexical processing stage, or the prelexical processing stage, or both. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  6. Facilitating and hindering factors in Internet-delivered treatment for insomnia and depression

    Directory of Open Access Journals (Sweden)

    Kerstin Blom

    2016-05-01

    Proposed future research hypotheses: 1 A combination of CBT for insomnia and CBT for depression is more effective than only one of the treatments. 2 Additional therapist support increases outcomes for patients with more comorbidities. 3 Acceptance is a mechanism of change in CBT-i.

  7. Tool Use as Distributed Cognition: how tools help, hinder and define manual skill

    Directory of Open Access Journals (Sweden)

    Chris eBaber

    2014-02-01

    Full Text Available Our thesis in this paper is that, in order to appreciate the interplay between cognitive (goal-directed and physical performance in tool use, it is necessary to determine the role that representations play in the use of tools. We argue that rather being solely a matter of internal (mental representation, tool use makes use of the external representations that define the human-environment-tool-object system. This requires the notion of Distributed Cognition to encompass not simply the manner in which artefacts represent concepts but also how they represent praxis. Our argument is that this can be extended to include how artefacts-in-context afford use and how this response to affordances constitutes a particular form of skilled performance. By artefacts-in-context, we do not mean solely the affordances offered by the physical dimensions of a tool but also the interaction between the tool and the object that it is being used on. From this, ‘affordance’ does not simply relate to the physical appearance of the tool but anticipates subsequent actions by the user directed towards the goal of changing the state of the object and this is best understood in terms of the ‘complimentarity’ in the system. This assertion raises two challenges which are explored in this paper. The first is to distinguish ‘affordance’ from the adaptation that one might expect to see in descriptions of motor control; when we speak of ‘affordance’ as a form of anticipation, don’t we just mean the ability to adjust movements in response to physical demands? The second is to distinguish ‘affordance’ from a schema of the tool; when we talk about anticipation, don’t we just mean the ability to call on a schema representing a ‘recipe’ for using that tool for that task? This question of representation, specifically what knowledge needs to be represented in tool use, is central to this paper.don

  8. Identifying barriers that hinder onsite parental involvement in a school-based health promotion program.

    Science.gov (United States)

    Garcia-Dominic, Oralia; Wray, Linda A; Treviño, Roberto P; Hernandez, Arthur E; Yin, Zenong; Ulbrecht, Jan S

    2010-09-01

    We investigated whether barriers to onsite parental involvement in the Bienestar Health Program Parent Component could be identified and whether participation rates could be increased by addressing these barriers. All nonparticipating parents of fourth-grade students of San Antonio Independent School District from 4 schools, which were selected randomly from 20 intervention schools in Bienestar, were invited to take part in this study. A total of 47 of 223 (21%) parents engaged in one of four focus groups offered. Parents identified barriers to their involvement in Bienestar that fit into five descriptive categories: (a) low value, (b) high cost, (c) competing family demands, (d) concerns about the program design, and (e) social role norms. The Bienestar Parent Component was then modified according to the focus group findings, which resulted in a marked increase in parental involvement from 17% to 37% overall. These findings suggest that even when parents are involved in the initial design of parent-friendly and culturally sensitive programs, as was the case for Bienestar, maximizing parental involvement may require additional assessment, identification, and remediation of barriers.

  9. Antibacterial Properties of Dental Luting Agents: Potential to Hinder the Development of Secondary Caries

    Directory of Open Access Journals (Sweden)

    Erik Unosson

    2012-01-01

    Full Text Available A modified direct contact test was used to evaluate the antibacterial properties of four commercially available dental luting agents (RelyX Unicem, Ketac Cem, Ceramir Crown & Bridge and Harvard Cement and two reference materials (glass-ionomer cement and calcium aluminate cement compared to a negative-control material (PMMA. Streptococcus mutans bacteria were placed in direct contact with specimens that had been aged for 10 min, 1 day, and 7 days, in order to test the antibacterial properties of the materials. A metabolic assay containing resazurin was used to quantify the amount of viable bacteria remaining after the direct contact tests. The effects of pH and fluoride on bacteria proliferation were also evaluated. Strongest antibacterial properties were found for calcium aluminate cement, followed by Ceramir Crown & Bridge and RelyX Unicem. Ketac Cem, Harvard Cement, and the reference glass-ionomer cement showed bacteria content either higher than or not significantly different from the PMMA control in all instances. pH levels below 6.3 and above 9.0 were found to have negative effects on bacterial proliferation. No correlation between either acidic materials or fluoride release and antibacterial properties could be seen; rather, basic materials showed stronger antibacterial properties.

  10. Evaluating the predictivity of virtual screening for ABL kinase inhibitors to hinder drug resistance

    DEFF Research Database (Denmark)

    Gani, Osman A B S M; Narayanan, Dilip; Engh, Richard A

    2013-01-01

    Virtual screening methods are now widely used in early stages of drug discovery, aiming to rank potential inhibitors. However, any practical ligand set (of active or inactive compounds) chosen for deriving new virtual screening approaches cannot fully represent all relevant chemical space...... for potential new compounds. In this study, we have taken a retrospective approach to evaluate virtual screening methods for the leukemia target kinase ABL1 and its drug-resistant mutant ABL1-T315I. 'Dual active' inhibitors against both targets were grouped together with inactive ligands chosen from different...... component analyses of chemical properties, can distinguish some decoy sets from active compounds, the addition of target structural information via docking improves enrichment, and explicit consideration of multiple target conformations (i.e. types I and II) achieves best enrichment of active versus...

  11. Erythromycin treatment hinders the induction of oral tolerance to fed ovalbumin

    Directory of Open Access Journals (Sweden)

    Sydney E. Lambert

    2012-07-01

    Full Text Available The mucosal immune system is constantly exposed to antigen, whether it be food antigen, commensal bacteria, or harmful antigen. It is essential that the mucosal immune system can distinguish between harmful and non-harmful antigens, and initiate an active immune response to clear the harmful antigens, while initiating a suppressive immune response (tolerance to non-harmful antigens. Oral tolerance is an immunologic hyporesponsiveness to an orally administered antigen and is important in preventing unnecessary gastrointestinal (GI tract inflammation, which can result in a number of autoimmune and hypersensitivity diseases. Probiotics (beneficial intestinal bacteria, T regulatory cells (Tregs, and dendritic cells (DCs are all essential for generating tolerance. Antibiotics are commonly prescribed to fight infections and often necessary for maintaining health, but they can disrupt the normal intestinal probiotic populations. There is increasing epidemiologic evidence that suggests that antibiotic usage correlates with the development of atopic or irritable bowel disorders, which often result due to a breakdown in immune tolerance. This study investigated the effect of the antibiotic erythromycin on oral tolerance induction to ovalbumin (OVA. The results demonstrated that antibiotic treatment prior to exposure to fed antigen prevents tolerance to that antigen, which may be associated with a reduction in intestinal Lactobacillus populations. Furthermore, antibiotic treatment resulted in a significant decrease in the tolerogenic CD11c+/CD11b+/CD8α- MLN DCs independent of tolerizing treatment. These results provide evidence that antibiotic treatment, potentially through its effects on tolerogenic DCs and intestinal microflora, may contribute to autoimmune and atopic disorders via a breakdown in tolerance and support prior epidemiologic studies correlating increased antibiotic usage with the development of these disorders.

  12. The Achievement Gap among Newcomer Immigrant Adolescents: Life Stressors Hinder Latina/o Academic Success

    Science.gov (United States)

    Patel, Sita G.; Barrera, Alinne Z.; Strambler, Michael J.; Muñoz, Ricardo F.; Macciomei, Erynn

    2016-01-01

    This study compares life stressors and school outcomes among newcomer immigrant adolescents from Latin America, Asia, and the Caribbean. Participants attended a predominantly low-income, urban international public high school in the northeast. The Latina/o students were exposed to more life stressors and had lower attendance and achievement than…

  13. Pitfalls of the Past: Learning Disabilities that Hinder TRADOC’s Institutional Agility

    Science.gov (United States)

    2015-05-23

    Army’s success in World War II. Judith Hicks Stiehm in U.S. Army War College: Military Education in a Democracy examined the history of the AWC...OK: University of Oklahoma Press, 2011), 49; Stiehm, Judith H., In the Wake of War: U.S. Army War College: Military Education in a Democracy...34-38; Robert Coram, Boyd: The Fighter Pilot Who Changed the Art of War (Boston: Brown Little, 2002), 327-44; Peter M. Senge et al., The Fifth

  14. Laptop Multitasking Hinders Classroom Learning for Both Users and Nearby Peers

    Science.gov (United States)

    Sana, Faria; Weston, Tina; Cepeda, Nicholas J.

    2013-01-01

    Laptops are commonplace in university classrooms. In light of cognitive psychology theory on costs associated with multitasking, we examined the effects of in-class laptop use on student learning in a simulated classroom. We found that participants who multitasked on a laptop during a lecture scored lower on a test compared to those who did not…

  15. Differentiation-dependent rearrangements of actin filaments and microtubules hinder apical endocytosis in urothelial cells.

    Science.gov (United States)

    Tratnjek, Larisa; Romih, Rok; Kreft, Mateja Erdani

    2017-08-01

    During differentiation, superficial urothelial cells (UCs) of the urinary bladder form the apical surface, which is almost entirely covered by urothelial plaques containing densely packed uroplakin particles. These urothelial plaques are the main structural components of the blood-urine permeability barrier in the urinary bladder. We have shown previously that endocytosis from the apical plasma membrane decreases during urothelial cell differentiation. Here, we investigated the role of actin filament and microtubule rearrangements in apical endocytosis of differentiating UCs cells using hyperplastic and normoplastic porcine urothelial models. Partially differentiated normal porcine UCs contained actin filaments in the subapical cytoplasm, while microtubules had a net-like appearance. In highly differentiated UCs, actin filaments mostly disappeared from the subapical cytoplasm and microtubules remained as a thin layer close to the apical plasma membrane. Inhibition of actin filament formation with cytochalasin-D in partially differentiated UCs caused a decrease in apical endocytosis. Depolymerisation of microtubules with nocodazole did not prevent endocytosis of the endocytotic marker WGA into the subapical cytoplasm; however, it abolished WGA transport to endolysosomal compartments in the central cytoplasm. Cytochalasin-D or nocodazole treatment did not significantly change apical endocytosis in highly differentiated UCs. In conclusion, we showed that the physiological differentiation-dependent or chemically induced redistribution and reorganization of actin filaments and microtubules impair apical endocytosis in UCs. Importantly, reduced apical endocytosis due to cytoskeletal rearrangements in highly differentiated UCs, together with the formation of rigid urothelial plaques, reinforces the barrier function of the urothelium.

  16. Cruise Missile Penaid Nonproliferation: Hindering the Spread of Countermeasures Against Cruise Missile Defenses

    Science.gov (United States)

    2014-01-01

    flare/chaff dispensers SOURCES: (Left) Thales promotional image; (right) W. Vinten Ltd. promotional image. Penaids of various types may need to be...As of July 28, 2014: http://www.rand.org/pubs/research_reports/RR378.html “ Thales Vicon 78 Series 500,” Jane’s Unmanned Aerial Vehicles and Targets

  17. SISTEM PELAYANAN PERIJINAN HO (HINDER ORDONNANNNTIE UNTUK KEGIATAN USAHA MIKRO, KECIL DAN MENENGAH (UMKM

    Directory of Open Access Journals (Sweden)

    Himawan Estu Bagijo

    2010-01-01

    Full Text Available Economic activities are an important think to support development. For those purpose licensing system is one issues make barrier to promote economic growth relay on Micro, Small and Middle Economic Activities. Base on this problem this article will discuss and find the best way to solve the relationship between licensing system and economic activities. The relation is to protect an environmental by license on the other hand and to promote economic growth for a small business.

  18. The Direct Perception Hypothesis: Perceiving the intention of another’s action hinders its precise imitation

    Directory of Open Access Journals (Sweden)

    Tom eFroese

    2014-02-01

    Full Text Available We argue that imitation is a learning response to unintelligible actions, especially to social conventions. Various strands of evidence are converging on this conclusion, but further progress has been hampered by an outdated theory of perceptual experience. Comparative psychology continues to be premised on the doctrine that humans and nonhuman primates only perceive others’ physical ‘surface behavior’, while mental states are perceptually inaccessible. However, a growing consensus in social cognition research accepts the Direct Perception Hypothesis: primarily we see what others aim to do; we do not infer it from their motions. Indeed, physical details are overlooked – unless the action is unintelligible. On this basis we hypothesize that apes’ propensity to copy the goal of an action, rather than its precise means, is largely dependent on its perceived intelligibility. Conversely, children copy means more often than adults and apes because, uniquely, much adult human behavior is completely unintelligible to unenculturated observers due to the pervasiveness of arbitrary social conventions, as exemplified by customs, rituals, and languages. We expect the propensity to imitate to be inversely correlated with the familiarity of cultural practices, as indexed by age and/or socio-cultural competence. The Direct Perception Hypothesis thereby helps to parsimoniously explain the most important findings of imitation research, including children’s over-imitation and other species-typical and age-related variations.

  19. Hazelnut and neuroprotection: Improved memory and hindered anxiety in response to intra-hippocampal Aβ injection.

    Science.gov (United States)

    Bahaeddin, Zahra; Yans, Asal; Khodagholi, Fariba; Hajimehdipoor, Homa; Sahranavard, Shamim

    2017-07-01

    Corylus avellana L. (hazelnut) is known to be a delicious and nutritious food. This study was carried out to evaluate the use of hazelnut as a therapy for memory impairment because in Iranian traditional medicine, it is recommended for those suffering from a particular type of dementia, with symptoms of Alzheimer's disease. In this study, rats were fed with hazelnut kernel [(without skin) 800 mg/kg/day] during 1 week before stereotaxic surgery to 24 hours before behavioral testing (in general, for 16 consecutive days) and the effect of hazelnut eating on memory, anxiety, neuroinflammation and apoptosis was assessed in the amyloid beta-injected rat. The results of this study showed that feeding with hazelnut improved memory, (which was examined by using Y-maze test and shuttle box apparatus), and reduced anxiety-related behavior, that was evaluated using elevated plus maze. Also, western blotting analysis of cyclooxygenase-2, interleukin-1β, tumor necrosis factor-α, B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein, and caspase-3 showed that hazelnut has an ameliorating effect on the neuroinflammation and apoptosis caused by Aβ. These findings suggest that hazelnut, as a dietary supplement, improves healthy aging and could be a beneficial diet for the treatment of AD.

  20. When does anxiety help or hinder cognitive test performance? The role of working memory capacity.

    Science.gov (United States)

    Owens, Matthew; Stevenson, Jim; Hadwin, Julie A; Norgate, Roger

    2014-02-01

    Cognitive interference theories (e.g. attentional control theory, processing efficiency theory) suggest that high levels of trait anxiety predict adverse effects on the performance of cognitive tasks, particularly those that make high demands on cognitive resources. We tested an interaction hypothesis to determine whether a combination of high anxiety and low working memory capacity (WMC) would predict variance in demanding cognitive test scores. Ninety six adolescents (12- to 14-years-old) participated in the study, which measured self-report levels of trait anxiety, working memory, and cognitive test performance. As hypothesized, we found that the anxiety-WMC interaction explained a significant amount of variance in cognitive test performance (ΔR(2) .07, p .10). In contrast, trait anxiety was negatively related to test performance in adolescents with low WMC (β = -.35, p < .05) and positively related to test performance in those with high WMC (β = .49, p < .01). The results of this study suggest that WMC moderates the relationship between anxiety and cognitive test performance and may be a determinant factor in explaining some discrepancies found in the literature. Further research is needed to fully understand the mechanisms involved. © 2012 The British Psychological Society.

  1. Energy Choices. Efficient Energy Use - possibilities and barriers; Vaegval Energi. Energieffektivisering - moejligheter och hinder

    Energy Technology Data Exchange (ETDEWEB)

    Jagemar, Lennart (CIT Energy Management AB, Goeteborg (Sweden)); Pettersson, Bertil (Chalmers EnergiCentrum, CEC, Chalmers Univ. of Technology, Goeteborg (Sweden))

    2009-02-15

    Sweden's total energy supply in 2006 amounted to a total of 624 TWh and was dominated by crude oil, nuclear fuels, biofuels and hydropower. Different types of losses in the system accounts for one third of the energy. The final energy consumption, i.e. delivery minus losses, was divided in the following way: industry 157 TWh, the habitat of 145 TWh (of which 19 TWh relates to Agriculture, Forestry, Fishery and other service and secondary homes) and transport of 101 TWh. For the transport sector, studies show that combinations of various efficiency measures ideally can achieve an reduction in energy use by between 60 and 75 percent. The Governmental Energy Efficiency Inquiry (EnEff - 2008) estimated that the domestic transport techno-economic efficiency potential up to 2016 is 13 TWh (mainly fuel) of the total delivered energy is 87 TWh under EnEff. The potential about 5 TWh is expected to be completed by current instruments. The study assesses that despite the increased need for transport in 2016 the sector's energy use can remain at the same level or even be reduced. Buildings have a large technical and economic energy efficiency potential. According to EnEff's assessment, the streamlining potential is 33 TWh of which 8 TWh can implemented in 2016 with today's instruments. This compares with the total delivered energy is 151 TWh under EnEff. The total energy efficiency potential for buildings by 2020 is considered to be substantially higher, about 41 TWh, and affect the use of district heating, fuel and electricity. New powerful tools must be implemented for the building sector in order to realize the potential energy efficiency measures. Industry's total energy potential is assessed to be around 13 TWh by 2016. Industry's total energy use is 155 TWh according to EnEff. Only 2 TWh can realistically be saved up to 2016 taking into account a reasonable acceptance factor. The beneficiaries of the carbon emissions trade account for about four-fifths of industry fossil fuel use and therefore has the greatest energy efficiency potential in absolute terms. According Eneffs final report the total energy efficiency potential for that part of the industry is about 7 TWh. Efficiency potential to 2016 for the industry not covered by the emissions trading amounts to just 6 TWh per year. Eneff believe that the industry's total energy use by 2016 may correspond to the present use at an expected increased production output, provided that additional stimulating instruments are deployed. Such a development requires that almost all of the industry's profitable energy efficiency potential (nearly 11 TWh) is realized. Possible energy efficiency potential for the industry, based on previous studies (IVAs Energiframsyn) were 10 and 15 percent, which totals 15 to 20 TWh. Finally in this report, a qualitative analysis is made of the consequences of ambitious energy efficiency measures, mainly the effects on volumes and relative importance of the different energy carriers for a twenty year term

  2. Fermentation broth components influence droplet coalescence and hinder advanced biofuel recovery during fermentation

    NARCIS (Netherlands)

    Heeres, A.S.; Schroën, C.G.P.H.; Heijnen, J.J.; Wielen, van der L.A.M.; Cuellar, M.C.

    2015-01-01

    Developments in synthetic biology enabled the microbial production of long chain hydrocarbons, which can be used as advanced biofuels in aviation or transportation. Currently, these fuels are not economically competitive due to their production costs. The current process offers room for improvement:

  3. Factors That Help and Hinder Scientific Training in Counseling and Clinical Psychology Students

    Science.gov (United States)

    Marks, Margaret M.

    2011-01-01

    The purpose of this dissertation is to better understand scientific training within clinical and counseling psychology doctoral programs. A primary goal is to extend previous research by expanding the scientific training outcome variables from research interest and productivity to include additional characteristics of scientific mindedness such as…

  4. Woontevredenheid en hinder in woonbuurten met industriele bedrijvigheid. Analyse van 'Telefonisch Leefsituatie Onderzoek'-data

    NARCIS (Netherlands)

    Poll R van; Stellato R; Kruize H; Heijsterkamp S; MGO

    2003-01-01

    In many of the Dutch national policy plans, environmental quality is a strong guiding principle. From an environmental science and policy perspective, environmental quality at the local level is affected by sound, odour and air pollution, as well as external safety risks. This study examines the

  5. Turbulence triggers vigorous swimming but hinders motion strategy in planktonic copepods

    Science.gov (United States)

    Michalec, François-Gaël; Souissi, Sami; Holzner, Markus

    2015-01-01

    Calanoid copepods represent a major component of the plankton community. These small animals reside in constantly flowing environments. Given the fundamental role of behaviour in their ecology, it is especially relevant to know how copepods perform in turbulent flows. By means of three-dimensional particle tracking velocimetry, we reconstructed the trajectories of hundreds of adult Eurytemora affinis swimming freely under realistic intensities of homogeneous turbulence. We demonstrate that swimming contributes substantially to the dynamics of copepods even when turbulence is significant. We show that the contribution of behaviour to the overall dynamics gradually reduces with turbulence intensity but regains significance at moderate intensity, allowing copepods to maintain a certain velocity relative to the flow. These results suggest that E. affinis has evolved an adaptive behavioural mechanism to retain swimming efficiency in turbulent flows. They suggest the ability of some copepods to respond to the hydrodynamic features of the surrounding flow. Such ability may improve survival and mating performance in complex and dynamic environments. However, moderate levels of turbulence cancelled gender-specific differences in the degree of space occupation and innate movement strategies. Our results suggest that the broadly accepted mate-searching strategies based on trajectory complexity and movement patterns are inefficient in energetic environments. PMID:25904528

  6. Getting inside the Insider Researcher: Does Race-Symmetry Help or Hinder Research?

    Science.gov (United States)

    Vass, Greg

    2017-01-01

    This article engages with methodological concerns connected to insider education research and the "race-symmetry" shared between the researcher and teacher participants. To do this, race critical reflexive strategies are utilized to show how and why this practice productively contributed to the knowledge about race making constructed in…

  7. Direct observation of hindered eccentric rotation of an individual molecule : Cu-phthalocyanine on C60

    NARCIS (Netherlands)

    Stöhr, Meike; Wagner, T; Gabriel, M; Weyers, B; Moller, R

    2002-01-01

    Individual Cu-phthalocyanine molecules have been investigated by scanning tunnel microscopy on a closed packed film of C-60 at various temperatures. The molecules are found to bind asymmetrically to one C-60. While they remain in one position at low temperature, they can hop between six equivalent

  8. Hindered rotation of a copper phthalocyanine molecule on C60 : Experiments and molecular mechanics calculations

    NARCIS (Netherlands)

    Fendrich, M.; Wagner, Th.; Stöhr, M.; Möller, R.

    2006-01-01

    If copper phthalocyanine (CuPc) molecules are deposited on a Au(111) surface covered with a monolayer of C60, the molecules are found to adsorb individually onto the close-packed layer of C60. As the adsorption site of the CuPc is not symmetric with respect to the underlying C60 layer, the CuPc

  9. Implementing Human Resources Management (HRM) within Dutch VET Institutions: Examining the Fostering and Hindering Factors

    Science.gov (United States)

    Runhaar, Piety; Sanders, Karin

    2013-01-01

    Vocational Education and Training (VET) Institutions face serious challenges, like the implementation of competence-based education and upcoming teacher shortages, which urge them to implement Human Resources Management policy and practices (HRM). The implementation of HRM, however, often stagnates. This paper describes a qualitative study--in…

  10. Reaction of a sterically hindered iron(III porphyrin with peroxyacetic acid: degradation kinetics

    Directory of Open Access Journals (Sweden)

    P. PRAKASH

    2005-09-01

    Full Text Available A kinetic analysis of the reaction between peracetic acid (AcOOH, and tetrakis (pentafluorophenyl - 21H, 23H-porphine iron(III chloride, Fe(F20TPPCl, in acetonitrile showed that the peracetic acid oxidatively destroys Fe(F20TPPCl. This is in contrast to an assumption that the oxidative degradation of metalloporphyrins can be prevented by the introduction of electron-withdrawing substituents into the phenyl groups of the porphyrin ligand. A UV-visible spectroscopic study showed a degree of macro cycle destruction of the tetrapyrrole conjucation of the metalloporphyrin. The degradation takes place via oxoperferryl species. The first step of the reaction mechanism is the reversible formation of an adduct ’X’(k1/k-1 between Fe(F20TPPCl and peracetic acid, followed by an irreversible step (k2 for the formation of oxoperferryl species.

  11. Does the concept of safety culture help or hinder systems thinking in safety?

    Science.gov (United States)

    Reiman, Teemu; Rollenhagen, Carl

    2014-07-01

    The concept of safety culture has become established in safety management applications in all major safety-critical domains. The idea that safety culture somehow represents a "systemic view" on safety is seldom explicitly spoken out, but nevertheless seem to linger behind many safety culture discourses. However, in this paper we argue that the "new" contribution to safety management from safety culture never really became integrated with classical engineering principles and concepts. This integration would have been necessary for the development of a more genuine systems-oriented view on safety; e.g. a conception of safety in which human, technological, organisational and cultural factors are understood as mutually interacting elements. Without of this integration, researchers and the users of the various tools and methods associated with safety culture have sometimes fostered a belief that "safety culture" in fact represents such a systemic view about safety. This belief is, however, not backed up by theoretical or empirical evidence. It is true that safety culture, at least in some sense, represents a holistic term-a totality of factors that include human, organisational and technological aspects. However, the departure for such safety culture models is still human and organisational factors rather than technology (or safety) itself. The aim of this paper is to critically review the various uses of the concept of safety culture as representing a systemic view on safety. The article will take a look at the concepts of culture and safety culture based on previous studies, and outlines in more detail the theoretical challenges in safety culture as a systems concept. The paper also presents recommendations on how to make safety culture more systemic. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Infrared Flares from M Dwarfs: a Hinderance to Future Transiting Exoplanet Studies

    OpenAIRE

    Davenport, James R. A.

    2017-01-01

    Many current and future exoplanet missions are pushing to infrared (IR) wavelengths where the flux contrast between the planet and star is more favorable (Deming et al. 2009), and the impact of stellar magnetic activity is decreased. Indeed, a recent analysis of starspots and faculae found these forms of stellar activity do not substantially impact the transit signatures or science potential for FGKM stars with JWST (Zellem et al. 2017). However, this is not true in the case of flares, which ...

  13. Interactions Between Forms of Memory: When Priming Hinders New Episodic Learning

    OpenAIRE

    Wagner, Anthony D.; Maril, Anat; Schacter, Daniel L.

    2000-01-01

    Human memory consists of multiple forms, including priming and explicit memory. Although considerable evidence indicates that priming and explicit memory are functionally and neuroanatomically distinct, little is know about when and how these different forms of memory interact. Here, behavioral and functional magnetic resonance imaging (fMRI) methods were used to examine a novel and counterintuitive hypothesis: Priming during episodic encoding may be negatively associated with subsequent expl...

  14. Globalization of authorship in the marketing discipline: Does it help or hinder the field?

    NARCIS (Netherlands)

    S. Stremersch (Stefan); P.C. Verhoef (Peter)

    2005-01-01

    textabstractMarketing scholars have reflected upon the marketing discipline's internal evolution before. However, no prior study has assessed the globalization of authorship in our discipline, let alone assessed its consequences for the field. This paper addresses the following two questions: (1) Is

  15. Carbamate Stabilities of Sterically Hindered Amines from Quantum Chemical Methods: Relevance ofr CO2 Capture

    NARCIS (Netherlands)

    Gangarapu, S.; Marcelis, A.T.M.; Zuilhof, H.

    2013-01-01

    The influence of electronic and steric effects on the stabilities of carbamates formed from the reaction of CO2 with a wide range of alkanolamines was investigated by quantum chemical methods. For the calculations, B3LYP, M11-L, MP2, and spin-component-scaled MP2 (SCS-MP2) methods were used, coupled

  16. The influence of environment in palliative care: supporting or hindering experiences of 'at-homeness'.

    Science.gov (United States)

    Rasmussen, Birgit H; Edvardsson, David

    2007-12-01

    Florence Nightingale stated that the art of nursing is to provide an environment in which the patient is in the best position for nature to act upon, and Martha Rogers, in turn, emphasized that one part in nursing is to pattern the environment into a place where healing conditions are optimal. This paper presents a preliminary conceptual framework that describes the influence of environment in palliative care. Based on previously published studies, a conceptual framework describing the influence of environments in palliative care was developed consisting of an atmosphere of hospitality; an atmosphere of safety; and, an atmosphere of 'everydayness'. The framework describes that the atmosphere is created in the meeting between the person's needs/expectations and the environment, an atmosphere that can influence experiential outcomes of 'at-homeness' or homelessness in the palliative care setting. In conclusion, this preliminary conceptual framework may contribute to nursing practice by providing a conceptual basis for actively reflecting on and evaluating the atmosphere in palliative care settings.

  17. Losartan Administration Reduces Fibrosis but Hinders Functional Recovery after Volumetric Muscle Loss Injury

    Science.gov (United States)

    2014-09-25

    to drinking water with or without losartan potassium powder (Santa Cruz Biotechnol- ogy) at 2.5, 10, or 30 mg·kg1·day1 from 3 days postinjury for 7...mal Care and Use Committee. Adult male Lewis rats (Harlan Labo- ratories, Indianapolis, IN) were housed in a vivarium accredited by the Association...nonfat dried milk . Membranes were then incubated overnight at 4°C in TBST containing 5% (wt/vol) bovine serum albumin and primary antibody for collagen

  18. Feedback Both Helps and Hinders Learning: The Causal Role of Prior Knowledge

    Science.gov (United States)

    Fyfe, Emily R.; Rittle-Johnson, Bethany

    2016-01-01

    Feedback can be a powerful learning tool, but its effects vary widely. Research has suggested that learners' prior knowledge may moderate the effects of feedback; however, no causal link has been established. In Experiment 1, we randomly assigned elementary school children (N = 108) to a condition based on a crossing of 2 factors: induced strategy…

  19. Photoinduced Copolymerization of APMP-MMA: The Role of Reactive Hindered Amine APMP

    National Research Council Canada - National Science Library

    Zhang, Ting; Fu, Liuwa; Chen, Zhikang; Cui, Yanyan; Liu, Xiaoxuan

    2016-01-01

    ..., the photoinduced polymerization is a generally economical and convenient technology that offers a number of advantages, including ambient temperature processing, fast curing, and spatial and temporal con...

  20. Fermentation broth components influence droplet coalescence and hinder advanced biofuel recovery during fermentation.

    Science.gov (United States)

    Heeres, Arjan S; Schroën, Karin; Heijnen, Joseph J; van der Wielen, Luuk A M; Cuellar, Maria C

    2015-08-01

    Developments in synthetic biology enabled the microbial production of long chain hydrocarbons, which can be used as advanced biofuels in aviation or transportation. Currently, these fuels are not economically competitive due to their production costs. The current process offers room for improvement: by utilizing lignocellulosic feedstock, increasing microbial yields, and using cheaper process technology. Gravity separation is an example of the latter, for which droplet growth by coalescence is crucial. The aim of this study was to study the effect of fermentation broth components on droplet coalescence. Droplet coalescence was measured using two setups: a microfluidic chip and regular laboratory scale stirred vessel (2 L). Some fermentation broth components had a large impact on droplet coalescence. Especially components present in hydrolysed cellulosic biomass and mannoproteins from the yeast cell wall retard coalescence. To achieve a technically feasible gravity separation that can be integrated with the fermentation, the negative effects of these components on coalescence should be minimized. This could be achieved by redesign of the fermentation medium or adjusting the fermentation conditions, aiming to minimize the release of surface active components by the microorganisms. This way, another step can be made towards economically feasible advanced biofuel production. © 2015 The Authors. Biotechnology Journal published by Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. This is an open access article under the terms of the Creative Commons Attribution-Non-Commercial-NoDerivs Licence, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

  1. Ortho-methylated 3-hydroxypyridines hinder hen egg-white lysozyme fibrillogenesis

    Science.gov (United States)

    Mariño, Laura; Pauwels, Kris; Casasnovas, Rodrigo; Sanchis, Pilar; Vilanova, Bartolomé; Muñoz, Francisco; Donoso, Josefa; Adrover, Miquel

    2015-07-01

    Protein aggregation with the concomitant formation of amyloid fibrils is related to several neurodegenerative diseases, but also to non-neuropathic amyloidogenic diseases and non-neurophatic systemic amyloidosis. Lysozyme is the protein involved in the latter, and it is widely used as a model system to study the mechanisms underlying fibril formation and its inhibition. Several phenolic compounds have been reported as inhibitors of fibril formation. However, the anti-aggregating capacity of other heteroaromatic compounds has not been studied in any depth. We have screened the capacity of eleven different hydroxypyridines to affect the acid-induced fibrillization of hen lysozyme. Although most of the tested hydroxypyridines alter the fibrillation kinetics of HEWL, only 3-hydroxy-2-methylpyridine, 3-hydroxy-6-methylpyridine and 3-hydroxy-2,6-dimethylpyridine completely abolish fibril formation. Different biophysical techniques and several theoretical approaches are combined to elucidate their mechanism of action. O-methylated 3-hydroxypyridines bind non-cooperatively to two distinct but amyloidogenic regions of monomeric lysozyme. This stabilises the protein structure, as evidenced by enhanced thermal stability, and results in the inhibition of the conformational transition that precedes fibril assembly. Our results point to o-methylated 3-hydroxypyridines as a promising molecular scaffold for the future development of novel fibrillization inhibitors.

  2. Ortho-methylated 3-hydroxypyridines hinder hen egg-white lysozyme fibrillogenesis

    OpenAIRE

    Laura Mariño; Kris Pauwels; Rodrigo Casasnovas; Pilar Sanchis; Bartolomé Vilanova; Francisco Muñoz; Josefa Donoso; Miquel Adrover

    2015-01-01

    Protein aggregation with the concomitant formation of amyloid fibrils is related to several neurodegenerative diseases, but also to non-neuropathic amyloidogenic diseases and non-neurophatic systemic amyloidosis. Lysozyme is the protein involved in the latter, and it is widely used as a model system to study the mechanisms underlying fibril formation and its inhibition. Several phenolic compounds have been reported as inhibitors of fibril formation. However, the anti-aggregating capacity of o...

  3. Ortho-methylated 3-hydroxypyridines hinder hen egg-white lysozyme fibrillogenesis

    National Research Council Canada - National Science Library

    Mariño, Laura; Pauwels, Kris; Casasnovas, Rodrigo; Sanchis, Pilar; Vilanova, Bartolomé; Muñoz, Francisco; Donoso, Josefa; Adrover, Miquel

    2015-01-01

    Protein aggregation with the concomitant formation of amyloid fibrils is related to several neurodegenerative diseases, but also to non-neuropathic amyloidogenic diseases and non-neurophatic systemic amyloidosis...

  4. Could Some Geriatric Characteristics Hinder the Prescription of Anticoagulants in Atrial Fibrillation in the Elderly?

    Directory of Open Access Journals (Sweden)

    Paule Denoël

    2014-01-01

    Full Text Available Several studies have reported underprescription of anticoagulants in atrial fibrillation (AF. We conducted an observational study on 142 out of a total of 995 consecutive ≥75 years old patients presenting AF (14% when admitted in an emergency unit of a general hospital, in search of geriatric characteristics that might be associated with the underprescription of anticoagulation therapy (mostly antivitamin K at the time of the study. The following data was collected from patients presenting AF: medical history including treatment and comorbidities, CHADS2 score, ISAR scale (frailty, Lawton’s scale (ADL, GDS scale (mood status, MUST (nutrition, and blood analysis (INR, kidney function, and albumin. Among those patients for who anticoagulation treatment was recommended (73%, only 61% were treated with it. In the group with anticoagulation therapy, the following characteristics were observed more often than in the group without such therapy: a recent (≤6 months hospitalization and medical treatment including digoxin or based on >3 different drugs. Neither the value of the CHADS2 score, nor the geriatric characteristics could be correlated with the presence or the absence of an anticoagulation therapy. More research is thus required to identify and clarify the relative importance of patient-, physician-, and health care system-related hurdles for the prescription of oral anticoagulation therapy in older patients with AF.

  5. Joint Cooling does not Hinder Athletic Performance during High-intensity Intermittent Exercise.

    Science.gov (United States)

    Kim, H; Lee, D; Choi, H-M; Park, J

    2016-07-01

    We examined the effects of ankle and knee joint cooling on 20-m sprint times and maximal vertical jump heights during high-intensity intermittent exercise. 21 healthy collegiate male basketball (n=14) and handball players (n=7) underwent 3 experimental sessions. Each session consisted of four 15-min quarters of high-intensity intermittent exercises including various intensities of 20-m shuttle running and jumping. A 20-min bilateral joint cooling (ankle, knee, or control-no cooling: in a counterbalanced order) was applied before quarters 1 and 3. After joint cooling, no warm-up activity other than the exercise protocol was given. The 20-m sprint times and maximal vertical jump heights in each experimental session were recorded at baseline (prior to quarter-1) and during each quarter. To test joint cooling effects over time, we performed 3×5 mixed model ANOVAs. Neither ankle nor knee joint cooling changed 20-m sprint times (F8,280=1.45; p=0.18) or maximal vertical jump heights (F8,280=0.76; p=0.64). However, a trend was observed in which joint cooling immediately decreased (quarters 1 and 3) but active warm-up for approximately 20 min improved 20-min sprint times (quarters 2 and 4). Our study suggests that athletic performance such as sprinting and jumping are not altered by joint cooling applied prior to or during high-intensity intermittent exercise. © Georg Thieme Verlag KG Stuttgart · New York.

  6. Does it help or hinder? Promotion of Innovation on the Internet and Citizens’ Right to Privacy

    NARCIS (Netherlands)

    Cave, J.; Bodea, G.; Kool, K.; Lieshout, M. van

    2011-01-01

    This study investigates the interplay between Internet innovation and privacy. We propose working definitions of innovation and privacy and review the literature about their interaction. We interpret the possible tensions and problems in terms of market and system failures and analyse the relevant

  7. Can a glass cockpit display help (or hinder) performance of novices in simulated flight training?

    Science.gov (United States)

    Wright, Stephen; O'Hare, David

    2015-03-01

    The analog dials in traditional GA aircraft cockpits are being replaced by integrated electronic displays, commonly referred to as glass cockpits. Pilots may be trained on glass cockpit aircraft or encounter them after training on traditional displays. The effects of glass cockpit displays on initial performance and potential transfer effects between cockpit display configurations have yet to be adequately investigated. Flight-naïve participants were trained on either a simulated traditional display cockpit or a simulated glass display cockpit. Flight performance was measured in a test flight using either the same or different cockpit display. Loss of control events and accuracy in controlling altitude, airspeed and heading, workload, and situational awareness were assessed. Preferences for cockpit display configurations and opinions on ease of use were also measured. The results revealed consistently poorer performance on the test flight for participants using the glass cockpit compared to the traditional cockpit. In contrast the post-flight questionnaire data revealed a strong subjective preference for the glass cockpit over the traditional cockpit displays. There was only a weak effect of prior training. The specific glass cockpit display used in this study was subjectively appealing but yielded poorer flight performance in participants with no previous flight experience than a traditional display. Performance data can contradict opinion data. The design of glass cockpit displays may present some difficulties for pilots in the very early stages of training. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  8. Exploitation of the complex chemistry of hindered amine stabilizers in effective plastics stabilization

    Czech Academy of Sciences Publication Activity Database

    Pospíšil, Jan; Pilař, Jan; Nešpůrek, Stanislav

    2007-01-01

    Roč. 13, č. 3 (2007), s. 119-132 ISSN 1083-5601. [International Plastics Additives and Modifiers Conference Addcon World /12./. Cologne, 17.10.2006-18.10.2006] R&D Projects: GA AV ČR KAN400720701 Institutional research plan: CEZ:AV0Z40500505 Keywords : HAS mechanism * thermostabilizing effect * HAS deactivation by acids Subject RIV: CA - Inorganic Chemistry Impact factor: 0.685, year: 2007

  9. Electronic Waste: DOD Is Recovering Materials, but Several Factors May Hinder Near-Term Expansion of These Efforts

    Science.gov (United States)

    2016-06-01

    conclusions based on our audit objectives. The Strategic and Critical Materials Stock Piling Act provides for the acquisition and retention of... Strategy for Electronic Stewardship, July 20, 2011. The federal government website on electronics stewardship references this guidance in the context...and other federal agency customers pay to obtain these recovered precious metals are below current market prices; customers are charged only for the

  10. Experimental evidence for helping and hindering by previous offspring in the cooperative-breeding Seychelles warbler Acrocephalus sechellensis

    NARCIS (Netherlands)

    Komdeur, Jan

    1994-01-01

    Prebreeding Seychelles warblers (Acrocephalus sechellensis) frequently act as helpers on their natal territory, aiding in territory defence, predator mobbing, nest-building, incubation (only females) and feeding dependent young of their parents. In some cases helpers could attain breeding status

  11. Sterically hindered electron-withdrawing ligands: the reactions of N-carbazolyl phosphines with rhodium and palladium centres.

    Science.gov (United States)

    Burrows, Andrew D; Mahon, Mary F; Varrone, Maurizio

    2004-10-21

    The series of N-carbazolyl phosphines PPh(3-n)(NC(12)H(8))(n)(n= 1, L1; n= 2, L2; n= 3, L3) has been synthesised using BuLi to generate the N-carbazolyl lithium salt, followed by reaction with the appropriate chlorophosphine. The reactions between [Rh(mu-Cl)(CO)(2)](2) and four equivalents of L1 or L2 gave [RhCl(CO)(L1)(2)] 1 and [RhCl(CO)(L2)(2)] 2, though attempts to synthesise the analogous complex using L3 resulted in the formation of [Rh(mu-Cl)(CO)(L3)](2) 3 instead. The inability of L3 to cleave the chloride bridges can be related to its considerable steric requirements. The electronic properties of L1-3 were assessed by comparison of the nu(CO) values of the [Rh(acac)(CO)(L1-3)] complexes 4-6. The increase in number of N-carbazolyl substituents at the phosphorus atom results in a decrease of the sigma-donor and increase in the pi-acceptor character in the order L1 L2 L1-3 with [PdCl(2)(cod)] only L1 was able to displace cod from the metal centre and form [PdCl(2)(L1)(2)] 7. The use of [PdCl(2)(NCMe)(2)] instead of [PdCl(2)(cod)] resulted in the formation of the complexes [PdCl(2)(L1)(2)] 7 from L1, the cyclometallated complex [Pd(mu-Cl)[P(NC(12)H(8))(2)(NC(12)H(7))-kappa(2)P,C

  12. 21st Century Changes in Precipitation Extremes Over the United States: Can Climate Analogues Help or Hinder?

    Science.gov (United States)

    Gao, X.; Schlosser, C. A.

    2013-12-01

    Global warming is expected to alter the frequency and/or magnitude of extreme precipitation events. Such changes could have substantial ecological, economic, and sociological consequences. However, climate models in general do not correctly reproduce the frequency and intensity distribution of precipitation, especially at the regional scale. In this study, gridded data from a dense network of surface precipitation gauges and a global atmospheric analysis at a coarser scale are combined to develop a diagnostic framework for the large-scale meteorological conditions (i.e. flow features, moisture supply) that dominate during extreme precipitation. Such diagnostic framework is first evaluated with the late 20th century simulations from an ensemble of climate models participating in the Coupled Model Intercomparison Project Phase 5 (CMIP5), and is found to produce more consistent (and less uncertain) total and interannaul number of extreme days with the observations than the model-based precipitation over the south-central United States and the Western United States examined in this study. The framework is then applied to the CMIP5 multi-model projections for two radiative forcing scenarios (Representative Concentration Pathways 4.5 and 8.5) to assess the potential future changes in the probability of precipitation extremes over the same study regions. We further analyze the accompanying circulation features and their changes that may be responsible for shifts in extreme precipitation in response to changed climate. The results from this study may guide hazardous weather watches and help society develop adaptive strategies for preventing catastrophic losses.

  13. How do postgraduate GP trainees regulate their learning and what helps and hinders them? A qualitative study

    Directory of Open Access Journals (Sweden)

    Sagasser Margaretha H

    2012-08-01

    Full Text Available Abstract Background Self-regulation is essential for professional development. It involves monitoring of performance, identifying domains for improvement, undertaking learning activities, applying newly learned knowledge and skills and self-assessing performance. Since self-assessment alone is ineffective in identifying weaknesses, learners should seek external feedback too. Externally regulated educational interventions, like reflection, learning portfolios, assessments and progress meetings, are increasingly used to scaffold self-regulation. The aim of this study is to explore how postgraduate trainees regulate their learning in the workplace, how external regulation promotes self-regulation and which elements facilitate or impede self-regulation and learning. Methods In a qualitative study with a phenomenologic approach we interviewed first- and third-year GP trainees from two universities in the Netherlands. Twenty-one verbatim transcripts were coded. Through iterative discussion the researchers agreed on the interpretation of the data and saturation was reached. Results Trainees used a short and a long self-regulation loop. The short loop took one week at most and was focused on problems that were easy to resolve and needed minor learning activities. The long loop was focused on complex or recurring problems needing multiple and planned longitudinal learning activities. External assessments and formal training affected the long but not the short loop. The supervisor had a facilitating role in both loops. Self-confidence was used to gauge competence.Elements influencing self-regulation were classified into three dimensions: personal (strong motivation to become a good doctor, interpersonal (stimulation from others and contextual (organizational and educational features. Conclusions Trainees did purposefully self-regulate their learning. Learning in the short loop may not be visible to others. Trainees should be encouraged to actively seek and use external feedback in both loops. An important question for further research is which educational interventions might be used to scaffold learning in the short loop. Investing in supervisor quality remains important, since they are close to trainee learning in both loops.

  14. Organizational Cultural Factors Hindering Women Ascending to Top Management Positions in Public Universities in Kenya: A Case of Moi University

    Science.gov (United States)

    Makori, Rebecca S.; Onyango, Maria; Attyang, Judith Miguda; Bantu, Edward; Onderi, Peter Omae

    2016-01-01

    It is observed that the major setback to economic development in Kenya is stagnation in industrial development. To overcome these, Kenya plans to be a middle level income nation by the year 2030. These plans are to be realized through "Vision 2030." To achieve these goals, Kenya requires gender mainstreamed team of highly skilled workers…

  15. Hindered diffusion of asphaltenes at elevated temperature and pressure. [Semi-annual report], September 20, 1995--March 20, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Guin, J.A.

    1996-04-12

    In this study equilibrium adsorption isotherms were determined for two petroleum asphaltenes, AAD-1 and AAK-1, and one coal asphaltene, called No. 97500. Isotherms were determined for three different temperatures, namely 20, 35 and 50{degrees}C. The experimental data for the petroleum asphaltenes were fitted with a Freundlich isotherm. For the coal asphaltene a Freundlich isotherm was used to fit the experimental data for lower concentrations; however, for higher concentrations a linear isotherm fitted the experimental data better. The coal asphaltene showed a tendency to form multilayers on the catalyst surface. Upon comparison of the adsorption isotherms for the three different temperatures, an interesting effect was observed. Although a decrease of the asphaltenes adsorption for higher temperatures was expected, the adsorption as a function of the temperature in fact showed a maximum for the petroleum asphaltenes and a minimum for the coal asphaltenes. This interesting and unexpected behavior was speculated to be due to the formation of micelles in the coal asphaltene solution and the different dependence of micelle formation and adsorption on temperature. Comparing the adsorption isotherms for the three different asphaltenes revealed that the adsorption of the coal asphaltenes was initially lower than the adsorption of the petroleum asphaltenes, but increased more rapidly, finally becoming near and even greater than the adsorption of the petroleum asphaltenes. This was suggested to be due to the tendency of coal asphaltenes for multilayer adsorption on the solid surface.

  16. Aromatic inhibitors derived from ammonia-pretreated lignocellulose hinder bacterial ethanologenesis by activating regulatory circuits controlling inhibitor efflux and detoxification

    Directory of Open Access Journals (Sweden)

    David H. Keating

    2014-08-01

    Full Text Available Efficient microbial conversion of lignocellulosic hydrolysates to biofuels is a key barrier to the economically viable deployment of lignocellulosic biofuels. A chief contributor to this barrier is the impact on microbial processes and energy metabolism of lignocellulose-derived inhibitors, including phenolic carboxylates, phenolic amides (for ammonia-pretreated biomass, phenolic aldehydes, and furfurals. To understand the bacterial pathways induced by inhibitors present in ammonia-pretreated biomass hydrolysates, which are less well studied than acid-pretreated biomass hydrolysates, we developed and exploited synthetic mimics of ammonia-pretreated corn stover hydrolysate (ACSH. To determine regulatory responses to the inhibitors normally present in ACSH, we measured transcript and protein levels in an Escherichia coli ethanologen using RNA-seq and quantitative proteomics during fermentation to ethanol of synthetic hydrolysates containing or lacking the inhibitors. Our study identified four major regulators mediating these responses, the MarA/SoxS/Rob network, AaeR, FrmR, and YqhC. Induction of these regulons was correlated with a reduced rate of ethanol production, buildup of pyruvate, depletion of ATP and NAD(PH, and an inhibition of xylose conversion. The aromatic aldehyde inhibitor 5-hydroxymethylfurfural appeared to be reduced to its alcohol form by the ethanologen during fermentation, whereas phenolic acid and amide inhibitors were not metabolized. Together, our findings establish that the major regulatory responses to lignocellulose-derived inhibitors are mediated by transcriptional rather than translational regulators, suggest that energy consumed for inhibitor efflux and detoxification may limit biofuel production, and identify a network of regulators for future synthetic biology efforts.

  17. Expression of RNA virus proteins by RNA polymerase II dependent expression plasmids is hindered at multiple steps

    Directory of Open Access Journals (Sweden)

    Überla Klaus

    2007-06-01

    Full Text Available Abstract Background Proteins of human and animal viruses are frequently expressed from RNA polymerase II dependent expression cassettes to study protein function and to develop gene-based vaccines. Initial attempts to express the G protein of vesicular stomatitis virus (VSV and the F protein of respiratory syncytial virus (RSV by eukaryotic promoters revealed restrictions at several steps of gene expression. Results Insertion of an intron flanked by exonic sequences 5'-terminal to the open reading frames (ORF of VSV-G and RSV-F led to detectable cytoplasmic mRNA levels of both genes. While the exonic sequences were sufficient to stabilise the VSV-G mRNA, cytoplasmic mRNA levels of RSV-F were dependent on the presence of a functional intron. Cytoplasmic VSV-G mRNA levels led to readily detectable levels of VSV-G protein, whereas RSV-F protein expression remained undetectable. However, RSV-F expression was observed after mutating two of four consensus sites for polyadenylation present in the RSV-F ORF. Expression levels could be further enhanced by codon optimisation. Conclusion Insufficient cytoplasmic mRNA levels and premature polyadenylation prevent expression of RSV-F by RNA polymerase II dependent expression plasmids. Since RSV replicates in the cytoplasm, the presence of premature polyadenylation sites and elements leading to nuclear instability should not interfere with RSV-F expression during virus replication. The molecular mechanisms responsible for the destabilisation of the RSV-F and VSV-G mRNAs and the different requirements for their rescue by insertion of an intron remain to be defined.

  18. Lack of knowledge and availability of diagnostic equipment could hinder the diagnosis of sarcopenia and its management

    NARCIS (Netherlands)

    Reijnierse, Esmee M.; De Van Der Schueren, Marian A.E.; Trappenburg, Marijke C.; Doves, Marjan; Meskers, Carel G.M.; Maier, Andrea B.

    2017-01-01

    Objectives: Sarcopenia is an emerging clinical challenge in an ageing population and is associated with serious negative health outcomes. This study aimed to assess the current state of the art regarding the knowledge about the concept of sarcopenia and practice of the diagnostic strategy and

  19. Hybridization of two biotypes of Lilioceris cheni will not hinder biological control of air potato, Dioscorea bulbifera

    Science.gov (United States)

    Dioscorea bulbifera L. (Dioscoreales: Dioscoreaceae), air potato, is a perennial vine native to Asia and Africa that is invasive in Florida and other parts of the southeastern United States. Air potato vines can grow more than 20 meters long and outcompete native vegetation in a variety of habitats....

  20. Synthesis, spectroscopic properties, and magnetic properties of complexes of VO(II) with salicylaldimines containing sterically hindered phenols

    Energy Technology Data Exchange (ETDEWEB)

    Kasumov, V.T.; Medzhidov, A.A.

    1987-11-01

    Complexes of VO(II) with salicylaldimines obtained from derivatives of salicylaldehyde and 2,6-di-tert-butyl-4 aminophenol have been synthesized. The spectroscopic (IR, ESR, and optical) and magnetic properties have been studied. The IR spectra of the complexes display stretching vibrations of OH, C=N, and V=O groups at 3625-3640, 1608-1615, and 985-990 cm/sup -1/, respectively. The electronic spectra in THF, in contrast to the case of CHCl/sub 3/, do not show a band with a frequency corresponding to 590 nm, and they show a shift to longer wavelengths at 930 nm, apparently due to the interaction of the complexes with THF molecules. The parameters of the spin Hamiltonian have been determined from the ESR spectra. The values found for the magnetic moments (1.66-1.83 Bohr magnetons) indicate that weak ferromagnetism is observed in the polycrystalline stage in cases of disubstituted compounds. When the complexes are oxidized with PbO/sub 2/ in solutions in toluene and CHCl/sub 3/, a decrease in the intensity of the ESR signal of the vanadyl ions and the formation of free phenoxyl radicals are observed.

  1. Factors that may Facilitate or Hinder a Family-Focus in the Treatment of Parents with a Mental Illness

    NARCIS (Netherlands)

    Lauritzen, C.; Reedtz, C.; Doesum, K.T.M. van; Martinussen, M.

    2015-01-01

    Children with mentally ill parents are at risk of developing mental health problems themselves. To enhance early support for these children may prevent mental health problems from being transmitted from one generation to the next. The sample (N = 219) included health professionals in a large

  2. Working-class Filipino women's perspectives on factors that facilitate or hinder prenatal micronutrients supplementation to prevent congenital anomalies.

    Science.gov (United States)

    Daack-Hirsch, Sandra; Gamboa, Henrietta

    2012-11-01

    The study was conducted to plan for a community-health campaign to inform working-class Filipinos about the causes and prevention of orofacial clefting. Prenatal micronutrients may play a role in preventing orofacial clefting. Therefore, women's practices and perspectives on barriers to and facilitators of micronutrient supplementation were elicited. A total of 43 women and 22 health care workers were interviewed. Barriers to taking supplements included side effects, late prenatal care, the view that micronutrients are medications, inadequate supply, and health care workers who were unaware that prenatal vitamin supplements prevent congenital anomalies. The main facilitator was women's understanding that prenatal micronutrients improve the physical well-being of both mother and child. Given that women view having healthy babies as a reason to take micronutrients and that the health care workers lacked knowledge related to the use of micronutrients to prevent congenital anomalies, uptake of prenatal micronutrient supplementation programs may improve by specifically promoting the health benefit of preventing congenital anomalies.

  3. Rescue therapy with Tanshinone IIA hinders transition of acute kidney injury to chronic kidney disease via targeting GSK3β

    Science.gov (United States)

    Jiang, Chunming; Zhu, Wei; Yan, Xiang; Shao, Qiuyuan; Xu, Biao; Zhang, Miao; Gong, Rujun

    2016-01-01

    Acute kidney injury (AKI) remains challenging for clinical practice and poses a risk of developing progressive chronic kidney disease (CKD) with no definitive treatment available yet. Tanshinone IIA, an active ingredient of Chinese herbal Salvia miltiorrhiza, has been widely used in Asia for the remarkable organoprotective activities. Its effect on established AKI, however, remains unknown. In mice with folic acid-induced AKI, delayed treatment with Tanshinone IIA, commenced early or late after injury, diminished renal expression of kidney injury markers, reduced apoptosis and improved kidney dysfunction, concomitant with mitigated histologic signs of AKI to CKD transition, including interstitial fibrosis and tubular atrophy, and with an ameliorated inflammatory infiltration in tubulointerstitium and a favored M2-skewed macrophage polarization. Mechanistically, Tanshinone IIA blunted glycogen synthase kinase (GSK)3β overactivity and hyperactivation of its downstream mitogen-activated protein kinases that are centrally implicated in renal fibrogenesis and inflammation. Inhibition of GSK3β is likely a key mechanism mediating the therapeutic activity of Tanshinone IIA, because sodium nitroprusside, a GSK3β activator, largely offset its renoprotective effect. In confirmatory studies, rescue treatment with Tanshinone IIA likewise ameliorated ischemia/reperfusion-induced kidney destruction in mice. Our data suggest that Tanshinone IIA represents a valuable treatment that improves post-AKI kidney salvage via targeting GSK3β. PMID:27857162

  4. Macrophage-derived osteopontin is fragmented by MMP-9 to hinder angiogenesis in the post-myocardial infarction left ventricle

    DEFF Research Database (Denmark)

    Nielsen, Signe Holm; Flynn, E.R.; Lindsey, M.

    2017-01-01

    Extracellular matrix (ECM) turnover is a key event during remodeling of the left ventricle (LV) following myocardial infarction (MI). Turnover includes ECM degradation of existing ECM to remove necrotic myocytes and synthesis to produce new ECM to form the infarct scar. Matrix metalloproteinases ...

  5. Mechanistic Evaluation of Motion in Redox-Driven Rotaxanes Reveals Longer Linkers Hasten Forward Escape's and Hinder Backward Translations

    DEFF Research Database (Denmark)

    Andersen, S. S.; Share, A. I.; Poulsen, B. L.

    2014-01-01

    Mechanistic understanding of the translational movements in molecular switches is essential for designing machine-like prototypes capable of following set pathways of motion. To this end, we demonstrated that increasing the station-to-station distance will speed up the linear movements forward...

  6. Recombination does not hinder formation or detection of ecological species of Synechococcus inhabiting a hot spring cyanobacterial mat

    Directory of Open Access Journals (Sweden)

    Melanie Crystal Melendrez

    2016-01-01

    Full Text Available Recent studies of bacterial speciation have claimed to support the biological species concept—that reduced recombination is required for bacterial populations to diverge into species. This conclusion has been reached from the discovery that ecologically distinct clades show lower rates of recombination than that which occurs among closest relatives. However, these previous studies did not attempt to determine whether the more-rapidly recombining close relatives within the clades studied may also have diversified ecologically, without benefit of sexual isolation. Here we have measured the impact of recombination on ecological diversification within and between two ecologically distinct clades (A and B´ of Synechococcus in a hot spring microbial mat in Yellowstone National Park, using a cultivation-free, multi-locus approach. Bacterial artificial chromosome (BAC libraries were constructed from mat samples collected at 60°C and 65°C. Analysis of multiple linked loci near Synechococcus 16S rRNA genes showed little evidence of recombination between the A and B´ lineages, but a record of recombination was apparent within each lineage. Recombination and mutation rates within each lineage were of similar magnitude, but recombination had a somewhat greater impact on sequence diversity than mutation, as also seen in many other bacteria and archaea. Despite recombination within the A and B´ lineages, there was evidence of ecological diversification within each lineage. The algorithm Ecotype Simulation identified sequence clusters consistent with ecologically distinct populations (ecotypes, and several hypothesized ecotypes were distinct in their habitat associations and in their adaptations to different microenvironments. We conclude that sexual isolation is more likely to follow ecological divergence than to precede it. Thus, an ecology-based model of speciation appears more appropriate than the biological species concept for bacterial and archaeal diversification.

  7. Implementing family involvement in the treatment of patients with psychosis: a systematic review of facilitating and hindering factors.

    Science.gov (United States)

    Eassom, Erica; Giacco, Domenico; Dirik, Aysegul; Priebe, Stefan

    2014-10-03

    To synthesise the evidence on implementing family involvement in the treatment of patients with psychosis with a focus on barriers, problems and facilitating factors. Systematic review of studies evaluating the involvement of families in tripartite communication between health professionals, 'families' (or other unpaid carers) and adult patients, in a single-family context. A theoretical thematic analysis approach and thematic synthesis were used. A systematic electronic search was carried out in seven databases, using database-specific search strategies and controlled vocabulary. A secondary manual search of grey literature was performed as well as using forwards and backwards snowballing techniques. A total of 43 studies were included. The majority featured qualitative data (n=42), focused solely on staff perspectives (n=32) and were carried out in the UK (n=23). Facilitating the training and ongoing supervision needs of staff are necessary but not sufficient conditions for a consistent involvement of families. Organisational cultures and paradigms can work to limit family involvement, and effective implementation appears to operate via a whole team coordinated effort at every level of the organisation, supported by strong leadership. Reservations about family involvement regarding power relations, fear of negative outcomes and the need for an exclusive patient-professional relationship may be explored and addressed through mutually trusting relationships. Implementing family involvement carries additional challenges beyond those generally associated with translating research to practice. Implementation may require a cultural and organisational shift towards working with families. Family work can only be implemented if this is considered a shared goal of all members of a clinical team and/or mental health service, including the leaders of the organisation. This may imply a change in the ethos and practices of clinical teams, as well as the establishment of working routines that facilitate family involvement approaches. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  8. Smartphones as assistive technology following traumatic brain injury: a preliminary study of what helps and what hinders.

    Science.gov (United States)

    Wong, Dana; Sinclair, Kelly; Seabrook, Elizabeth; McKay, Adam; Ponsford, Jennie

    2017-11-01

    Smartphones have great potential as a convenient, multifunction tool to support cognition and independence following traumatic brain injury (TBI). However, there has been limited investigation of their helpful and less helpful aspects for people with TBI. We aimed to investigate patterns of smartphone use amongst individuals with TBI, identify potential barriers to use, and examine the relationships between smartphone use and daily functioning. Twenty-nine participants with TBI and 33 non-injured participants completed the Smartphone Survey, and measures of subjective and objective cognitive functioning, mood, and community integration. Smartphone use was equally common in both groups, and patterns of app use were similar. More participants with TBI than the comparison group listed using their smartphone as a memory aid as its main benefit. Difficulty in learning how to use the smartphone was identified by participants with TBI, however only 10% had been shown how to use it by a clinician. Those with poorer subjective cognitive function used memory/organisational apps more frequently; and higher communication app use with better social integration, in participants with TBI. These findings suggest that smartphones have potential in improving independence following TBI, but receiving support in using them is vital. Implications for Rehabilitation Smartphones are accessible, acceptable, convenient devices for most individuals with traumatic brain injury (TBI), and are perceived as a useful memory and organizational aid as well as having multiple other helpful functions. Use of communication apps such as text messages and social media is associated with better social and community integration in people with TBI. Direct instruction on how to use smartphone apps is more important for people with TBI than for non-injured individuals. Developers of apps designed for this population should prioritize ease of app use, large displays, and availability of technical support, while maintaining an engaging design and interface.

  9. The Potential of β Carbolin Alkaloids to Hinder Growth and Re¬verse Chloroquine Resistance in Plasmodium falciparum

    Directory of Open Access Journals (Sweden)

    Zaid O IBRAHEEM

    2015-12-01

    Full Text Available Background: Nowadays, scourge of malaria as a fatalistic disease has increased due to emergence of drug resistance and tolerance among different strains of Plasmodium falciparum. Emergence of chloroquine (CQ resistance has worsened the calamity as CQ is still considered the most efficient, safe and cost effective drug among other antimalarials. This urged the scientists to search for other alternatives or sensitizers that may be able to augment CQ action and reverse its resistance. Method: Three β-carbolin derivatives, namely, harmalin, harmol and harmalol were tested for their anti-plasmodial and CQ resistance reversal effects against P. falciparum 3D7 and K1. SYBRE Green-1 based drug sensitivity assay and isobologram analysis were used to screen the mentioned effects respectively. Results: All of them showed moderate anti-plasmodium effect and harmalin was the most effective as compared to the others in reversing CQ resistance and tolerance. Conclusion: The mentioned phytochemicals are not ideal to be used as conven­tional anti-malarials and only harmalin can be suggested to reverse CQ resistance in P. falciparum K1.

  10. Nanomedicines for cancer therapy: state-of-the-art and limitations to pre-clinical studies that hinder future developments

    Science.gov (United States)

    Dawidczyk, Charlene; Russell, Luisa; Searson, Peter

    2014-08-01

    The ability to efficiently deliver a drug or gene to a tumor site is dependent on a wide range of factors including circulation time, interactions with the mononuclear phagocyte system, extravasation from circulation at the tumor site, targeting strategy, release from the delivery vehicle, and uptake in cancer cells. Nanotechnology provides the possibility of creating delivery systems where the design constraints are decoupled, allowing new approaches for reducing the unwanted side effects of systemic delivery, increasing tumor accumulation, and improving efficacy. The physico-chemical properties of nanoparticle-based delivery platforms introduce additional complexity associated with pharmacokinetics and tumor accumulation. To assess the impact of nanoparticle-based delivery systems, we first review the design strategies and pharmacokinetics of FDA-approved nanomedicines. Next we review nanomedicines under development, summarizing the range of nanoparticle platforms, strategies for targeting, and pharmacokinetics. We show how the lack of uniformity in preclinical trials prevents systematic comparison and hence limits advances in the field.

  11. Promoting universal financial protection: evidence from seven low- and middle-income countries on factors facilitating or hindering progress.

    Science.gov (United States)

    McIntyre, Di; Ranson, Michael K; Aulakh, Bhupinder K; Honda, Ayako

    2013-09-24

    Although universal health coverage (UHC) is a global health policy priority, there remains limited evidence on UHC reforms in low- and middle-income countries (LMICs). This paper provides an overview of key insights from case studies in this thematic series, undertaken in seven LMICs (Costa Rica, Georgia, India, Malawi, Nigeria, Tanzania, and Thailand) at very different stages in the transition to UHC.These studies highlight the importance of increasing pre-payment funding through tax funding and sometimes mandatory insurance contributions when trying to improve financial protection by reducing out-of-pocket payments. Increased tax funding is particularly important if efforts are being made to extend financial protection to those outside formal-sector employment, raising questions about the value of pursuing contributory insurance schemes for this group. The prioritisation of insurance scheme coverage for civil servants in the first instance in some LMICs also raises questions about the most appropriate use of limited government funds.The diverse reforms in these countries provide some insights into experiences with policies targeted at the poor compared with universalist reform approaches. Countries that have made the greatest progress to UHC, such as Costa Rica and Thailand, made an explicit commitment to ensuring financial protection and access to needed care for the entire population as soon as possible, while this was not necessarily the case in countries adopting targeted reforms. There also tends to be less fragmentation in funding pools in countries adopting a universalist rather than targeting approach. Apart from limiting cross-subsidies, fragmentation of pools has contributed to differential benefit packages, leading to inequities in access to needed care and financial protection across population groups; once such differentials are entrenched, they are difficult to overcome. Capacity constraints, particularly in purchasing organisations, are a pervasive problem in LMICs. The case studies also highlighted the critical role of high-level political leadership in pursuing UHC policies and citizen support in sustaining these policies.This series demonstrates the value of promoting greater sharing of experiences on UHC reforms across LMICs. It also identifies key areas of future research on health care financing in LMICs that would support progress towards UHC.

  12. Broadening the regulated-river management paradigm: A case study of the forgotten dead zone hindering Pallid Sturgeon recovery

    Science.gov (United States)

    Guy, Christopher S.; Treanor, Hilary B.; Kappenman, Kevin M.; Scholl, Eric A.; Ilgen, Jason E.; Webb, Molly A. H.

    2015-01-01

    The global proliferation of dams within the last half century has prompted ecologists to understand the effects of regulated rivers on large-river fishes. Currently, much of the effort to mitigate the influence of dams on large-river fishes has been focused on downriver effects, and little attention has been given to upriver effects. Through a combination of field observations and laboratory experiments, we tested the hypothesis that abiotic conditions upriver of the dam are the mechanism for the lack of recruitment in Pallid Sturgeon (Scaphirhynchus albus), an iconic large-river endangered species. Here we show for the first time that anoxic upriver habitat in reservoirs (i.e., the transition zone between the river and reservoir) is responsible for the lack of recruitment in Pallid Sturgeon. The anoxic condition in the transition zone is a function of reduced river velocities and the concentration of fine particulate organic material with high microbial respiration. As predicted, the river upstream of the transition zone was oxic at all sampling locations. Our results indicate that transition zones are an ecological sink for Pallid Sturgeon. We argue that ecologists, engineers, and policy makers need to broaden the regulated-river paradigm to consider upriver and downriver effects of dams equally to comprehensively mitigate altered ecosystems for the benefit of large-river fishes, especially for the Pallid Sturgeon.

  13. The New Juan Crow in Education: Revealing Panoptic Measures and Inequitable Resources That Hinder Latina/o Postsecondary Pathways

    Science.gov (United States)

    Madrigal-Garcia, Yanira I.; Acevedo-Gil, Nancy

    2016-01-01

    This qualitative study examined the distribution of inequitable resources, a culture of control, and implications for postsecondary pathways for Latinas/os in five California high schools. This study integrated critical race theory in education, school culture, and the concept of "panopticon" to examine school structures, climate, and…

  14. Nanomedicines for cancer therapy: state-of-the-art and limitations to pre-clinical studies that hinder future developments

    Directory of Open Access Journals (Sweden)

    Charlene eDawidczyk

    2014-08-01

    Full Text Available The ability to efficiently deliver a drug or gene to a tumor site is dependent on a wide range of factors including circulation time, interactions with the mononuclear phagocyte system, extravasation from circulation at the tumor site, targeting strategy, release from the delivery vehicle, and uptake in cancer cells. Nanotechnology provides the possibility of creating delivery systems where the design constraints are decoupled, allowing new approaches for reducing the unwanted side effects of systemic delivery, increasing tumor accumulation, and improving efficacy. The physico-chemical properties of nanoparticle-based delivery platforms introduce additional complexity associated with pharmacokinetics and tumor accumulation. To assess the impact of nanoparticle-based delivery systems, we first review the design strategies and pharmacokinetics of FDA-approved nanomedicines. Next we review nanomedicines under development, summarizing the range of nanoparticle platforms, strategies for targeting, and pharmacokinetics. We show how the lack of uniformity in preclinical trials prevents systematic comparison and hence limits advances in the field.

  15. Repairing nerve gaps by vein conduits filled with lipoaspirate-derived entire adipose tissue hinders nerve regeneration.

    Science.gov (United States)

    Papalia, Igor; Raimondo, Stefania; Ronchi, Giulia; Magaudda, Ludovico; Giacobini-Robecchi, Maria G; Geuna, Stefano

    2013-05-01

    In spite of great recent advancements, the definition of the optimal strategy for bridging a nerve defect, especially across long gaps, still remains an open issue since the amount of autologous nerve graft material is limited while the outcome after alternative tubulization techniques is often unsatisfactory. The aim of this study was to investigate a new tubulization technique based on the employment of vein conduits filled with whole subcutaneous adipose tissue obtained by lipoaspiration. In adult rats, a 1cm-long defect of the left median nerve was repaired by adipose tissue-vein-combined conduits and compared with fresh skeletal muscle tissue-vein-combined conduits and autologous nerve grafts made by the excised nerve segment rotated by 180°. Throughout the postoperative period, functional recovery was assessed using the grasping test. Regenerated nerve samples were withdrawn at postoperative month-6 and processed for light and electron microscopy and stereology of regenerated nerve fibers. Results showed that functional recovery was significantly slower in the adipose tissue-enriched group in comparison to both control groups. Light and electron microscopy showed that a large amount of adipose tissue was still present inside the vein conduits at postoperative month-6. Stereology showed that all quantitative morphological predictors analyzed performed significantly worse in the adipose tissue-enriched group in comparison to the two control groups. On the basis of this experimental study in the rat, the use of whole adipose tissue for tissue engineering of peripheral nerves should be discouraged. Pre-treatment of adipose tissue aimed at isolating stromal vascular fraction and/or adipose derived stem/precursor cells should be considered a fundamental requisite for nerve repair. Copyright © 2012 Elsevier GmbH. All rights reserved.

  16. Exploring primary school English language teachers’ perceptions of INSET in Malaysia : factors which promoted and hindered professional development

    OpenAIRE

    Pang, Elaine L. L.; Wray, David

    2016-01-01

    The national concern to improve the level of education in Malaysia prompted the Ministry of Education to conduct a comprehensive review of the education system and introduce the Malaysia Education Blueprint (2013-2025) to transform the education system. One of the aims was to upgrade the quality of in-service teacher training for teachers. This has resulted in a reshaping of the type of courses and delivery mode for in-service education for teachers (INSET) into a top-down, national priority ...

  17. Staying awake: a genetic region that hinders α2 adrenergic receptor agonist-induced loss of consciousness

    NARCIS (Netherlands)

    Gelegen, C.; Gent, T.C.; Ferretti, V.; Zhang, Z.; Yustos, R.; Lan, F.; Yang, Q.; Overington, D.W.U.; Vyssotsky, A.L.; van Lith, H.A.|info:eu-repo/dai/nl/091342422; Wisden, W.; Franks, N.P.

    2014-01-01

    How external stimuli prevent the onset of sleep has been little studied. This is usually considered to be a non-specific type of phenomenon. However, the hypnotic drug dexmedetomidine, an agonist at a2 adrenergic receptors, has unusual properties that make it useful for investigating this question.

  18. Contextual attributes promote or hinder self-regulated learning: A qualitative study contrasting rural physicians with undergraduate learners in Japan.

    Science.gov (United States)

    Matsuyama, Yasushi; Nakaya, Motoyuki; Okazaki, Hitoaki; Leppink, Jimmie; van der Vleuten, Cees

    2017-11-26

    Previous studies support the notion that East Asian medical students do not possess sufficient self-regulation for postgraduate clinical training. However, some East Asian physicians who are employed in geographically isolated and educationally underserved rural settings can self-regulate their study during the early phase of their postgraduate career. To explore the contextual attributes that contribute to self-regulated learning (SRL), we examined the differences in self-regulation between learning as an undergraduate and in a rural context in East Asia. We conducted interviews and diary data collection among rural physicians (n = 10) and undergraduates (n = 11) in Japan who undertook self-study of unfamiliar diseases. We analyzed three domains of Zimmerman's definition of SRL: learning behaviors, motivation, and metacognition using constructivist grounded theory. Rural physicians recognized their identity as unique, and as professionals with a central role of handling diseases in the local community by conducting self-study. They simultaneously found themselves being at risk of providing inappropriate aid if their self-study was insufficient. They developed strategic learning strategies to cope with this high-stakes task. Undergraduates had a fear of being left behind and preferred to remain as one of the crowd with students in the same school year. Accordingly, they copied the methods of other students for self-study and used monotonous and homogeneous strategies. Different learning contexts do not keep East Asian learners from being self-regulated. Awareness of their unique identity leads them to view learning tasks as high-stakes, and to initiate learning strategies in a self-regulated manner. Teacher-centered education systems cause students to identify themselves as one of the crowd, and tasks as low-stakes, and to accordingly employ non-self-regulated strategies.

  19. Uncertainty of measurement and clinical value of semen analysis: has standardisation through professional guidelines helped or hindered progress?

    Science.gov (United States)

    Tomlinson, M J

    2016-09-01

    This article suggests that diagnostic semen analysis has no more clinical value today than it had 25-30 years ago, and both the confusion surrounding its evidence base (in terms of relationship with conception) and the low level of confidence in the clinical setting is attributable to an associated high level of 'uncertainty'. Consideration of the concept of measurement uncertainty is mandatory for medical laboratories applying for the ISO15189 standard. It is evident that the entire semen analysis process is prone to error every step from specimen collection to the reporting of results and serves to compound uncertainty associated with diagnosis or prognosis. Perceived adherence to published guidelines for the assessment of sperm concentration, motility and morphology does not guarantee a reliable and reproducible test result. Moreover, the high level of uncertainty associated with manual sperm motility and morphology can be attributed to subjectivity and lack a traceable standard. This article describes where and why uncertainty exists and suggests that semen analysis will continue to be of limited value until it is more adequately considered and addressed. Although professional guidelines for good practice have provided the foundations for testing procedures for many years, the risk in following rather prescriptive guidance to the letter is that unless they are based on an overwhelmingly firm evidence base, the quality of semen analysis will remain poor and the progress towards the development of more innovative methods for investigating male infertility will be slow. © 2016 American Society of Andrology and European Academy of Andrology.

  20. Potato virus Y infection hinders potato defence response and renders plants more vulnerable to Colorado potato beetle attack.

    Science.gov (United States)

    Petek, Marko; Rotter, Ana; Kogovšek, Polona; Baebler, Spela; Mithöfer, Axel; Gruden, Kristina

    2014-11-01

    In the field, plants are challenged by more than one biotic stressor at the same time. In this study, the molecular interactions between potato (Solanum tuberosum L.), Colorado potato beetle (Leptinotarsa decemlineata Say; CPB) and Potato virus Y(NTN) (PVY(NTN) ) were investigated through analyses of gene expression in the potato leaves and the gut of the CPB larvae, and of the release of potato volatile compounds. CPB larval growth was enhanced when reared on secondary PVY(NTN) -infected plants, which was linked to decreased accumulation of transcripts associated with the antinutritional properties of potato. In PVY(NTN) -infected plants, ethylene signalling pathway induction and induction of auxin response transcription factors were attenuated, while no differences were observed in jasmonic acid (JA) signalling pathway. Similarly to rearing on virus-infected plants, CPB larvae gained more weight when reared on plants silenced in JA receptor gene (coi1). Although herbivore-induced defence mechanism is regulated predominantly by JA, response in coi1-silenced plants only partially corresponded to the one observed in PVY(NTN) -infected plants, confirming the role of other plant hormones in modulating this response. The release of β-barbatene and benzyl alcohol was different in healthy and PVY(NTN) -infected plants before CPB larvae infestation, implicating the importance of PVY(NTN) infection in plant communication with its environment. This was reflected in gene expression profiles of neighbouring plants showing different degree of defence response. This study thus contributes to our understanding of plant responses in agro-ecosystems. © 2014 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.

  1. Factors Hindering the Deployment of Female Teachers to Headship Positions in Public Primary Schools in Nambale Sub-County, Kenya

    Science.gov (United States)

    Mukolwe, Joseph O.; Okwara, Michael; Ajowi, O. Jack

    2016-01-01

    Worldwide, women representation in management and leadership positions is marginal. Despite immense academic advancement by women, few of them do advance to management positions. In Kenya, women make up a critical portion of human resource base. However, they are grossly underrepresented at leadership positions. This situation is reflected in…

  2. What Helps and Hinders Indigenous Student Success in Higher Education Health Programmes: A Qualitative Study Using the Critical Incident Technique

    Science.gov (United States)

    Curtis, Elana; Wikaire, Erena; Kool, Bridget; Honey, Michelle; Kelly, Fiona; Poole, Phillippa; Barrow, Mark; Airini; Ewen, Shaun; Reid, Papaarangi

    2015-01-01

    Tertiary institutions aim to provide high quality teaching and learning that meet the academic needs for an increasingly diverse student body including indigenous students. "Tatou Tatou" is a qualitative research project utilising Kaupapa "Maori" research methodology and the Critical Incident Technique interview method to…

  3. Photosensitized electron transfer from sterically hindered amines to the benzophenone triplet and its reversion in solvents of different polarity

    Science.gov (United States)

    Kluge, T.; Brede, O.

    1998-06-01

    The reductive quenching of the benzophenone triplet by 2,2,6,6-tetramethyl- and 1,2,2,6,6-pentamethyl-piperidine was studied by laser flash photolysis. The rate constants for the quenching process were obtained in solvents of different polarity, acetonitrile, methanol, acetone, n-butanol, t-butanol, butyl chloride, chloroform, 1,4-dioxane, cyclohexane and benzene. The contact ion pair primarily formed, decays by proton transfer under the formation of the benzophenone ketyl radical, back electron transfer and charge separation. In our experiments no indication for the free solvated anion radical was found. The ketyl radical yields vary with solvent polarity, showing a minimum for the solvent butyl chloride. We explain this behaviour in terms of the solvent dependence of the back electron transfer process. Rate constants were determined for all reactions studied.

  4. What hinders the uptake of computerized decision support systems in hospitals? A qualitative study and framework for implementation.

    Science.gov (United States)

    Liberati, Elisa G; Ruggiero, Francesca; Galuppo, Laura; Gorli, Mara; González-Lorenzo, Marien; Maraldi, Marco; Ruggieri, Pietro; Polo Friz, Hernan; Scaratti, Giuseppe; Kwag, Koren H; Vespignani, Roberto; Moja, Lorenzo

    2017-09-15

    Advanced Computerized Decision Support Systems (CDSSs) assist clinicians in their decision-making process, generating recommendations based on up-to-date scientific evidence. Although this technology has the potential to improve the quality of patient care, its mere provision does not guarantee uptake: even where CDSSs are available, clinicians often fail to adopt their recommendations. This study examines the barriers and facilitators to the uptake of an evidence-based CDSS as perceived by diverse health professionals in hospitals at different stages of CDSS adoption. Qualitative study conducted as part of a series of randomized controlled trials of CDSSs. The sample includes two hospitals using a CDSS and two hospitals that aim to adopt a CDSS in the future. We interviewed physicians, nurses, information technology staff, and members of the boards of directors (n = 30). We used a constant comparative approach to develop a framework for guiding implementation. We identified six clusters of experiences of, and attitudes towards CDSSs, which we label as "positions." The six positions represent a gradient of acquisition of control over CDSSs (from low to high) and are characterized by different types of barriers to CDSS uptake. The most severe barriers (prevalent in the first positions) include clinicians' perception that the CDSSs may reduce their professional autonomy or may be used against them in the event of medical-legal controversies. Moving towards the last positions, these barriers are substituted by technical and usability problems related to the technology interface. When all barriers are overcome, CDSSs are perceived as a working tool at the service of its users, integrating clinicians' reasoning and fostering organizational learning. Barriers and facilitators to the use of CDSSs are dynamic and may exist prior to their introduction in clinical contexts; providing a static list of obstacles and facilitators, irrespective of the specific implementation phase and context, may not be sufficient or useful to facilitate uptake. Factors such as clinicians' attitudes towards scientific evidences and guidelines, the quality of inter-disciplinary relationships, and an organizational ethos of transparency and accountability need to be considered when exploring the readiness of a hospital to adopt CDSSs.

  5. An epoxide hydrolase secreted by Pseudomonas aeruginosa decreases mucociliary transport and hinders bacterial clearance from the lung.

    Science.gov (United States)

    Hvorecny, Kelli L; Dolben, Emily; Moreau-Marquis, Sophie; Hampton, Thomas H; Shabaneh, Tamer B; Flitter, Becca A; Bahl, Christopher D; Bomberger, Jennifer M; Levy, Bruce D; Stanton, Bruce A; Hogan, Deborah A; Madden, Dean R

    2018-01-01

    The opportunistic pathogen Pseudomonas aeruginosa colonizes the lungs of susceptible individuals by deploying virulence factors targeting host defenses. The secreted factor Cif (cystic fibrosis transmembrane conductance regulator inhibitory factor) dysregulates the endocytic recycling of CFTR and thus reduces CFTR abundance in host epithelial membranes. We have postulated that the decrease in ion secretion mediated by Cif would slow mucociliary transport and decrease bacterial clearance from the lungs. To test this hypothesis, we explored the effects of Cif in cultured epithelia and in the lungs of mice. We developed a strategy to interpret the "hurricane-like" motions observed in reconstituted cultures and identified a Cif-mediated decrease in the velocity of mucus transport in vitro. Presence of Cif also increased the number of bacteria recovered at two time points in an acute mouse model of pneumonia caused by P. aeruginosa. Furthermore, recent work has demonstrated an inverse correlation between the airway concentrations of Cif and 15-epi-lipoxin A4, a proresolving lipid mediator important in host defense and the resolution of pathogen-initiated inflammation. Here, we observe elevated levels of 15-epi-lipoxin A4 in the lungs of mice infected with a strain of P. aeruginosa that expresses only an inactive form of cif compared with those mice infected with wild-type P. aeruginosa. Together these data support the inclusion of Cif on the list of virulence factors that assist P. aeruginosa in colonizing and damaging the airways of compromised patients. Furthermore, this study establishes techniques that enable our groups to explore the underlying mechanisms of Cif effects during respiratory infection.

  6. En California dos pioneros: Uno en el pasado y otro en el presente

    OpenAIRE

    Mauricio Bermúdez

    2002-01-01

    Agost on Haraszthy buscando un clima para alivio de su enfermedad arribó en 1849 al sur de California donde se convirtió en el pionero al importar, sembrar y producir vino con Zinfandel, una entre otras muchas vides europeas. Construyó el viñedo Buena Vista diseñado para esa época con las mejores facilidades, no obstante, la empresa estaba destinada al colapso financiero por el incumplimiento del Estado de California; la vida de Agost on fue una aventura y tras su muerte una leyenda. En 1976 ...

  7. Filling quality of the reports of adverse drug reactions received at the Pharmacovigilance Centre of São Paulo (Brazil): missing information hinders the analysis of suspected associations.

    Science.gov (United States)

    Ribeiro, Adalton; Lima, Silvana; Zampieri, Maria-Elisa; Peinado, Mirtes; Figueras, Albert

    2017-12-01

    The completeness and accuracy of the reports of suspected adverse drug reactions is important in pharmacovigilance. The aim of the present study was to analyze the quality of the information included in the reports sent to the Pharmacovigilance Centre of São Paulo (Brazil). A sample of 999 reports received from January 2013 to December 2014 was selected. The quality of the filled information was evaluated according to a 'sufficiency' criterion to apply the Karch-Lasagna causality algorithm. There were 820 reports from manufacturers and 179 from health centres. Only 4.4% (44) were fully filled, thus allowing the adequate analysis of the causal relationship between the suspected medication and the adverse event. In 30% of the reports from manufacturers, the information about the critical variables was lacking or incomplete, preventing the adequate evaluation of the report. It was also noted that the reports' poor filling quality was not related with less severity or with old and well-known medicines. The poor quality of the information included in the reports received by this centre, especially those sent by pharmaceutical manufacturers, hampers the identification of potential safety signals. Measures to improve the quality of the reports must be urgently adopted.

  8. Disadvantaged by Degrees? How Widening Participation Students Are Not Only Hindered in Accessing HE, but Also during--and after--University

    Science.gov (United States)

    Budd, Richard

    2017-01-01

    There is no shortage of literature addressing the range of reasons why more disadvantaged groups are underrepresented in higher education--and particularly elite universities--in the UK, and it is clear that this has little to do with any real deficiency in terms of ability. This paper begins with an overview of this issue but then extends the…

  9. An internal focus of attention is not always as bad as its reputation: how specific aspects of internally focused attention do not hinder running efficiency.

    Science.gov (United States)

    Schücker, Linda; Knopf, Christian; Strauss, Bernd; Hagemann, Norbert

    2014-06-01

    The aim of this study was to examine differentiated effects of internally focused attention in endurance sports. Thirty-two active runners ran 24 min on a treadmill at a fixed speed of moderate intensity. For each 6-min block, participants had to direct their attention on different internal aspects (movement execution, breathing, or feeling of the body) or received no instructions. Oxygen consumption (VO2) was measured continuously to determine running economy. Results revealed that the different internal focus instructions had differentiated effects on VO2: A focus on breathing as well as a focus on the running movement led to higher VO2 than a focus on feeling of the body which showed similar VO2 as the control condition. We conclude that an internal focus of attention is solely detrimental to performance when directed to highly automated processes (e.g., breathing or movement). However, an internal focus on how the body feels during exercise does not disrupt movement efficiency.

  10. Efficient hydrolytic cleavage of plasmid DNA by chloro-cobalt(II) complexes based on sterically hindered pyridyl tripod tetraamine ligands: synthesis, crystal structure and DNA cleavage.

    Science.gov (United States)

    Massoud, Salah S; Perkins, Richard S; Louka, Febee R; Xu, Wu; Le Roux, Anne; Dutercq, Quentin; Fischer, Roland C; Mautner, Franz A; Handa, Makoto; Hiraoka, Yuya; Kreft, Gabriel L; Bortolotto, Tiago; Terenzi, Hernán

    2014-07-14

    Four new cobalt(ii) complexes [Co(6-MeTPA)Cl]ClO4/PF6 (2/2a), [Co(6-Me2TPA)Cl]ClO4/PF6 (3/3a), [Co(BPQA)Cl]ClO4/PF6 (4/4a) and [Co(BQPA)Cl]ClO4/PF6 (5/5a) as well as [Co(TPA)Cl]ClO4 (1) where TPA = tris(2-pyridylmethyl)amine, 6-MeTPA = ((6-methyl-2-pyridyl)methyl)bis(2-pyridylmethyl)amine, 6-Me2TPA = bis(6-methyl-2-pyridyl)methyl)-(2-pyridylmethyl)amine, BPQA = bis(2-pyridylmethyl)-(2-quinolylmethyl)-amine and BQPA = bis(2-quinolylmethyl)-(2-pyridylmethyl)amine were synthesized and structurally characterized. Single crystal X-ray crystallography confirmed the distorted trigonal bipyramidal geometries of complexes 2a-5a. Spectrophotometric titrations and conductivity measurements of the complexes in the CH3CN-H2O mixture showed that the chloro complexes exist in equilibrium with the corresponding hydrolyzed aqua species, [Co(L)(H2O)](2+). The pKa values of the coordinated H2O in aqua complexes vary from 8.4 to 8.7 (37 °C). The interactions of the complexes (1-5) with DNA have been investigated at pH = 7.0 and 9.0 (10 mM Tris-HCl buffer) and 37 °C where very high catalytic cleavage was observed. Under pseudo Michaelis-Menten kinetic conditions, the catalytic rate constants, kcat, decrease in the order 4>2>5>1>3. At pH 7.0 (10 mM Tris-HCl buffer) and 37 °C, the kcat value for complex 4 (6.02 h(-1)), where [Co(BPQA)(H2O)](2+) is the major species, corresponds to 170 million rate enhancement over the non-catalyzed DNA. Electrophoretic experiments conducted in the presence and absence of radical scavengers (DMSO, KI, NaN3) ruled out the oxidative mechanistic pathway of the reaction and suggested that the hydrolytic mechanism is the preferred one. This finding was in agreement with the observed increase in the kcat values at pH 9.0 compared to the corresponding values at pH 7.0 as a result of the increased concentration of the reactive hydroxo species, [Co(L)(OH)](+). The reactivity of the synthesized complexes in catalyzing the DNA cleavage is discussed in relation to the steric effect imposed by the coordinated pyridyl ligand around the central cobalt(ii) center.

  11. Family Influences on Self-Management Among Functionally Independent Adults with Diabetes or Heart Failure: Do Family Members Hinder As Much As They Help?

    Science.gov (United States)

    Rosland, Ann-Marie; Heisler, Michele; Choi, HwaJung; Silveira, Maria J.; Piette, John D

    2013-01-01

    Objectives Among functionally independent patients with diabetes or heart failure, we examined family member support and family-related barriers to self-care. We then identified patient characteristics associated with family support and family barriers and how each was associated with self-management adherence. Methods Cross-sectional survey of 439 patients with diabetes or heart failure (74% response rate). Results 75% of respondents reported supportive family involvement in self-care, however 25% reported frequent family-related barriers to self-care. Women reported family support less often (64% vs. 77%) and family barriers to self-care more often (30% vs. 21%) than men. 78% of respondents reported involved family members nagged or criticized them about illness care. In multivariate models, low health literacy, partnered status, and higher family function were associated with higher family support levels, while female gender, older age, higher education, and more depression symptoms were associated with family barriers to self-care. Family barriers were associated with lower disease care self-efficacy (pself-management adherence (both pself-care of these higher-functioning patients. Interventions should help patients with chronic illness overcome family barriers to self-care and help families use positive and effective support techniques. PMID:20308348

  12. "Are You Done?" Child Care Providers' Verbal Communication at Mealtimes that Reinforce or Hinder Children's Internal Cues of Hunger and Satiation

    Science.gov (United States)

    Ramsay, Samantha A.; Branen, Laurel J.; Fletcher, Janice; Price, Elizabeth; Johnson, Susan L.; Sigman-Grant, Madeleine

    2010-01-01

    Objective: To explore the verbal communication of child care providers regarding preschool children's internal and non-internal hunger and satiation cues. Methods: Video observation transcripts of Head Start staff (n=29) at licensed child care centers in Colorado, Idaho, and Nevada were analyzed for common themes. Results: Adults' verbal…

  13. Does obesity hinder radiotherapy in endometrial cancer patients? The implementation of new techniques in adjuvant radiotherapy – focus on obese patients

    OpenAIRE

    Małgorzata Moszyńska-Zielińska; Justyna Chałubińska-Fendler; Leszek Gottwald; Leszek Żytko; Ewelina Bigos; Jacek Fijuth

    2014-01-01

    The increasing incidence of obesity in Poland and its relation to endometrioid endometrial cancer (EEC) is resulting in the increasing necessity of treating obese women. Treatment of an overweight patient with EEC may impede not only the surgical procedures but also radiotherapy, especially external beam radiotherapy (EBRT). The problems arise both during treatment planning and when delivering each fraction due to the difficulty of positioning such a patient ? it implies the danger of underdo...

  14. Dossier Autarky. Own energy first. Without the net. Bureaucracy hinders self supply; Het Dossier Autarkie. Eigen energie eerst. Los van het net. Bureaucratie belemmert zelfvoorziening

    Energy Technology Data Exchange (ETDEWEB)

    Zeilmaker, R.

    2010-08-20

    Autarky in the field of energy is technically feasible and economically increasingly more attractive. The government makes it difficult for citizens to generate decentralized renewable energy with its bureaucracy and legislation. [Dutch] Autarkie op energiegebied is technisch mogelijk en ook economisch steeds aantrekkelijker bij stijgende rekeningen voor nutsvoorzieningen. De overheid maakt het burgers met bureaucratie en wetgeving echter lastig om decentraal duurzame energie op te wekken.

  15. In vitro antioxidant effects of estrogens with a hindered 3-OH function on the copper-induced oxidation of low density lipoprotein.

    Science.gov (United States)

    Miller, C P; Jirkovsky, I; Hayhurst, D A; Adelman, S J

    1996-05-01

    Estrogens with some bulky alkyl substituents in both the 2- and 4-positions have been synthesized and evaluated for the ability to inhibit the in vitro oxidation of low density lipoprotein as determined by the thiobarbituric reactive substances method. The present compounds with bulky groups in either the 2- or the 4-position (but not both the 2- and 4-) were especially effective as antioxidants, having IC50 values lower than either estradiol or probucol; however, they do not bind to the estrogen receptor with any great affinities (RBA role played by estrogens.

  16. The lack of adequate quality assurance/quality control data hinders the assessment of potential forest degradation in a national forest inventory

    Science.gov (United States)

    Thomas Brandeis; Stanley Zarnoch; Christopher Oswalt; Jeffery Stringer

    2017-01-01

    Hardwood lumber harvested from the temperate broadleaf and mixed broadleaf/conifer forests of the east-central United States is an important economic resource. Forest industry stakeholders in this region have a growing need for accurate, reliable estimates of high-quality wood volume. While lower-graded timber has an increasingly wide array of uses, the forest products...

  17. Social Impact of Stigma Regarding Tuberculosis Hindering Adherence to Treatment: A Cross Sectional Study Involving Tuberculosis Patients in Rajshahi City, Bangladesh.

    Science.gov (United States)

    Chowdhury, Md Rocky Khan; Rahman, Md Shafiur; Mondal, Md Nazrul Islam; Sayem, Abu; Billah, Baki

    2015-01-01

    Stigma, considered a social disease, is more apparent in developing societies which are driven by various social affairs, and influences adherence to treatment. The aim of the present study was to examine levels of social stigma related to tuberculosis (TB) in sociodemographic context and identify the effects of sociodemographic factors on stigma. The study sample consisted of 372 TB patients. Data were collected using stratified sampling with simple random sampling techniques. T tests, chi-square tests, and binary logistic regression analysis were performed to examine correlations between stigma and sociodemographic variables. Approximately 85.9% of patients had experienced stigma. The most frequent indicator of the stigma experienced by patients involved problems taking part in social programs (79.5%). Mean levels of stigma were significantly higher in women (55.5%), illiterate individuals (60.8%), and villagers (60.8%) relative to those of other groups. Chi-square tests revealed that education, monthly family income, and type of patient (pulmonary and extrapulmonary) were significantly associated with stigma. Binary logistic regression analysis demonstrated that stigma was influenced by sex, education, and type of patient. Stigma is one of the most important barriers to treatment adherence. Therefore, in interventions that aim to reduce stigma, strong collaboration between various institutions is essential.

  18. The Special Case of Disadvantaged Young People in Germany: How Stakeholder Interests Hinder Reform Proposals in Favour of a Training Guarantee

    Science.gov (United States)

    Granato, Mona; Krekel, Elisabeth M.; Ulrich, Joachim Gerd

    2015-01-01

    Every year, tens of thousands of young people in Germany fail to find access to dual vocational education and training (VET), because they cannot find a company to hire them as apprentices. This particularly affects persons with poor school leaving qualifications, socially deprived persons or people with a migrant background. In order to improve…

  19. Hindered Gamow-Teller Decay to the Odd-Odd N=Z Ga62: Absence of Proton-Neutron T =0 Condensate in A =62

    Science.gov (United States)

    Grodner, E.; Gadea, A.; Sarriguren, P.; Lenzi, S. M.; Grębosz, J.; Valiente-Dobón, J. J.; Algora, A.; Górska, M.; Regan, P. H.; Rudolph, D.; de Angelis, G.; Agramunt, J.; Alkhomashi, N.; Amon Susam, L.; Bazzacco, D.; Benlliure, J.; Benzoni, G.; Boutachkov, P.; Bracco, A.; Caceres, L.; Cakirli, R. B.; Crespi, F. C. L.; Domingo-Pardo, C.; Doncel, M.; Dombrádi, Zs.; Doornenbal, P.; Farnea, E.; Ganioǧlu, E.; Gelletly, W.; Gerl, J.; Gottardo, A.; Hüyük, T.; Kurz, N.; Leoni, S.; Mengoni, D.; Molina, F.; Morales, A. I.; Orlandi, R.; Oktem, Y.; Page, R. D.; Perez, D.; Pietri, S.; Podolyák, Zs.; Poves, A.; Quintana, B.; Rinta-Antila, S.; Rubio, B.; Nara Singh, B. S.; Steer, A. N.; Verma, S.; Wadsworth, R.; Wieland, O.; Wollersheim, H. J.

    2014-08-01

    Search for a new kind of superfluidity built on collective proton-neutron pairs with aligned spin is performed studying the Gamow-Teller decay of the T=1, Jπ=0+ ground state of Ge62 into excited states of the odd-odd N =Z nucleus Ga62. The experiment is performed at GSI Helmholtzzentrum für Shwerionenforshung with the Ge62 ions selected by the fragment separator and implanted in a stack of Si-strip detectors, surrounded by the RISING Ge array. A half-life of T1/2=82.9(14) ms is measured for the Ge62 ground state. Six excited states of Ga62, populated below 2.5 MeV through Gamow-Teller transitions, are identified. Individual Gamow-Teller transition strengths agree well with theoretical predictions of the interacting shell model and the quasiparticle random phase approximation. The absence of any sizable low-lying Gamow-Teller strength in the reported beta-decay experiment supports the hypothesis of a negligible role of coherent T =0 proton-neutron correlations in Ga62.

  20. Hindered Gamow-Teller decay to the odd-odd N=Z (62)Ga: absence of proton-neutron T=0 condensate in A=62.

    Science.gov (United States)

    Grodner, E; Gadea, A; Sarriguren, P; Lenzi, S M; Grebosz, J; Valiente-Dobón, J J; Algora, A; Górska, M; Regan, P H; Rudolph, D; de Angelis, G; Agramunt, J; Alkhomashi, N; Amon Susam, L; Bazzacco, D; Benlliure, J; Benzoni, G; Boutachkov, P; Bracco, A; Caceres, L; Cakirli, R B; Crespi, F C L; Domingo-Pardo, C; Doncel, M; Dombrádi, Zs; Doornenbal, P; Farnea, E; Ganioğlu, E; Gelletly, W; Gerl, J; Gottardo, A; Hüyük, T; Kurz, N; Leoni, S; Mengoni, D; Molina, F; Morales, A I; Orlandi, R; Oktem, Y; Page, R D; Perez, D; Pietri, S; Podolyák, Zs; Poves, A; Quintana, B; Rinta-Antila, S; Rubio, B; Nara Singh, B S; Steer, A N; Verma, S; Wadsworth, R; Wieland, O; Wollersheim, H J

    2014-08-29

    Search for a new kind of superfluidity built on collective proton-neutron pairs with aligned spin is performed studying the Gamow-Teller decay of the T=1, J(π)=0+ ground state of (62)Ge into excited states of the odd-odd N=Z nucleus (62)Ga. The experiment is performed at GSI Helmholtzzentrum für Shwerionenforshung with the (62)Ge ions selected by the fragment separator and implanted in a stack of Si-strip detectors, surrounded by the RISING Ge array. A half-life of T1/2=82.9(14)  ms is measured for the (62)Ge ground state. Six excited states of (62)Ga, populated below 2.5 MeV through Gamow-Teller transitions, are identified. Individual Gamow-Teller transition strengths agree well with theoretical predictions of the interacting shell model and the quasiparticle random phase approximation. The absence of any sizable low-lying Gamow-Teller strength in the reported beta-decay experiment supports the hypothesis of a negligible role of coherent T=0 proton-neutron correlations in (62)Ga.

  1. The role of stimulus cross-splicing in an event-related potentials study. Misleading formant transitions hinder automatic phonological processing.

    Science.gov (United States)

    Steinberg, Johanna; Truckenbrodt, Hubert; Jacobsen, Thomas

    2012-04-01

    The mental organization of linguistic knowledge and its involvement in speech processing can be investigated using the mismatch negativity (MMN) component of the auditory event-related potential. A contradiction arises, however, between the technical need for strict control of acoustic stimulus properties and the quest for naturalness and acoustic variability of the stimuli. Here, two methods of preparing speech stimulus material were compared. Focussing on the automatic processing of a phonotactic restriction in German, two corresponding sets of various vowel-fricative syllables were used as stimuli. The former syllables were naturally spoken while the latter ones were created by means of cross-splicing. Phonetically, natural and spliced syllables differed with respect to the appropriateness of coarticulatory information about the forthcoming fricative within the vowels. Spliced syllables containing clearly misleading phonetic information were found to elicit larger N2 responses compared to their natural counterparts. Furthermore, MMN results found for the natural syllables could not be replicated with these spliced stimuli. These findings indicate that the automatic processing of the stimuli was considerably affected by the stimulus preparation method. Thus, in spite of its unquestioned benefits for MMN experiments, the splicing technique may lead to interference effects on the linguistic factors under investigation.

  2. Will economic growth and fossil fuel scarcity help or hinder climate stabilization? Overview of the RoSE multi-model study

    NARCIS (Netherlands)

    Kriegler, Elmar; Mouratiadou, Ioanna; Luderer, Gunnar; Bauer, Nico; Brecha, Robert J.; Calvin, Katherine; De Cian, Enrica; Edmonds, Jae; Jiang, Kejun; Tavoni, Massimo; Edenhofer, Ottmar

    We investigate the extent to which future energy transformation pathways meeting ambitious climate change mitigation targets depend on assumptions about economic growth and fossil fuel availability. The analysis synthesizes results from the RoSE multi-model study aiming to identify robust and

  3. CD4 down regulation and raft dissociation by the non-depleting YTS177 antibody hinder murine T helper cell activities

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Cheng-Jang [Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan (China); Division of Biological Sciences, University of California, San Diego, La Jolla, CA, 92093 (United States); Lu, Chun-Hao [Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan (China); Chen, Li-Chen [Division of Allergy, Asthma, and Rheumatology, Department of Pediatrics, Chang Gung Memorial Hospital, Tao-Yuan, Taiwan (China); Nguyen, Duc T. [Division of Biological Sciences, University of California, San Diego, La Jolla, CA, 92093 (United States); Huang, Yi-Shu [Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan (China); Lin, Hsi-Hsien [Department of Microbiology and Immunology, Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan (China); Chang Gung Immunology Consortium, Chang Gung Memorial Hospital and Chang Gung University, Tao-Yuan, Taiwan (China); Department of Anatomic Pathology, Chang Gung Memorial Hospital, Tao-Yuan, Taiwan (China); Lin, Chun-Yen [Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan (China); Chang Gung Immunology Consortium, Chang Gung Memorial Hospital and Chang Gung University, Tao-Yuan, Taiwan (China); Department of Hepatogastroenterology, Chang Gung Memorial Hospital, Tao-Yuan, Taiwan (China); Kuo, Ming-Ling, E-mail: mingling@mail.cgu.edu.tw [Department of Microbiology and Immunology, Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan (China); Division of Allergy, Asthma, and Rheumatology, Department of Pediatrics, Chang Gung Memorial Hospital, Tao-Yuan, Taiwan (China); Chang Gung Immunology Consortium, Chang Gung Memorial Hospital and Chang Gung University, Tao-Yuan, Taiwan (China)

    2016-05-13

    Non-depleting YTS177 anti-CD4 monoclonal antibody (MoAb) has been reported to lead to antigen-specific immunotolerance in allograft transplantation and autoimmune diabetes, as well as possibly to inhibition of allergic inflammation in mice. However, the molecular mechanisms underlying hyporesponsive T cell responses induced by YTS177 MoAb remain elusive. Herein, we demonstrate that the YTS177 MoAb increases the levels of anergy factors p27{sup kip1} and Cbl-b, inhibits IL-2 production, and impairs calcium mobilization in activated T cells in vitro. YTS177 MoAb suppresses OVA-driven proliferation of DO11.10 CD4{sup +} T cells in vivo as well. Mechanistically, YTS177 MoAb induces tolerance by causing CD4 down-regulation through clathrin-dependent and raft dissociation. The results obtained in this study lead us to propose novel protective or curative approaches to CD4 T cell-mediated diseases.

  4. Novel 6FDA-based polyimides derived from sterically hindered Tröger's base diamines: Synthesis and gas permeation properties

    KAUST Repository

    Ghanem, Bader

    2016-04-30

    Two novel Tröger\\'s base-based di-o-substituted diamine monomers were synthesized and used to prepare two intrinsically microporous 6FDA-based polyimides (PIM-PI-TB-1 and PIM-PI-TB-2) with high molecular weight, high thermal stability and excellent solubility in common organic solvents. Compared to previously reported methods for preparing TB-based diamines, which are based on reduction of dimerized nitro-substituted anilines or condensation of phenylenediamine derivatives with dianhydrides, the novel protocol can be used to prepare different functionalized TB-based diamine monomers from a wide variety of aniline derivatives. PIM-PI-TB-1 (made from 6FDA and dibromo-tetramethyl-substituted TB diamine) and PIM-PI-TB-2 (made from 6FDA and tetramethyl-substituted TB diamine) are intrinsically microporous polymers with high BET surface areas of 440 m2/g and 580 m2/g, respectively. Pure-gas permeability coefficients of He, H2, N2, O2, CH4, and CO2 were measured at 35 °C and 2 bar for fresh and 180 days aged films. Both TB-based polyimides exhibited high gas permeability with moderate selectivity. The gas permeability dropped significantly coupled with a moderate increase in selectivity after long-term physical aging of 180 days.

  5. Does obesity hinder radiotherapy in endometrial cancer patients? The implementation of new techniques in adjuvant radiotherapy – focus on obese patients

    Directory of Open Access Journals (Sweden)

    Małgorzata Moszyńska-Zielińska

    2014-05-01

    Full Text Available The increasing incidence of obesity in Poland and its relation to endometrioid endometrial cancer (EEC is resulting in the increasing necessity of treating obese women. Treatment of an overweight patient with EEC may impede not only the surgical procedures but also radiotherapy, especially external beam radiotherapy (EBRT. The problems arise both during treatment planning and when delivering each fraction due to the difficulty of positioning such a patient – it implies the danger of underdosing targets and overdosing organs at risk. Willingness to use dynamic techniques in radiation oncology has increased for patients with EEC, even those who are obese. During EBRT careful daily verification is necessary for both safety and treatment accuracy. The most accurate method of verification is cone beam computed tomography (CBCT with soft tissue assessment, although it is time consuming and often requires a radiation oncologist. In order to improve the quality of such treatment, the authors present the practical aspects of planning and treatment itself by means of dynamic techniques in EBRT. The authors indicate the advantages and disadvantages of different types of on-board imaging (OBI verification images. Considering the scanty amount of literature in this field, it is necessary to conduct further research in order to highlight proper planning and treatment of obese endometrial cancer patients. The review of the literature shows that all centres that wish to use EBRT for gynaecological tumours should develop their own protocols on qualification, planning the treatment and methods of verifying the patients’ positioning.

  6. Implementation of new Healthy Conversation Skills to support lifestyle changes - what helps and what hinders? Experiences of Sure Start Children's Centre staff.

    Science.gov (United States)

    Tinati, Tannaze; Lawrence, Wendy; Ntani, Georgia; Black, Christina; Cradock, Sue; Jarman, Megan; Pease, Anna; Begum, Rufia; Inskip, Hazel; Cooper, Cyrus; Baird, Janis; Barker, Mary

    2012-07-01

    Effective communication is necessary for good relationships between healthcare practitioners and clients. This study examined barriers and facilitators to implementing new communication skills. One hundred and ten Sure Start Children's Centre staff attended one of 13 follow-up workshops in Southampton, UK between May 2009 and February 2011 to reflect on the use of new skills following a training course in communication, reflection and problem-solving. Barriers and facilitators were assessed with an adapted Problematic Experiences of Therapy scale (PETS). Staff reported frequency of skill use, and described what made it more difficult or easier to use the skills. Complete data were available for 101 trainees. The PETS indicated that staff had confidence in using the skills, but felt that there were practical barriers to using them, such as lack of time. Skills were used less often when staff perceived parents not to be engaging with them (Spearman's correlation r(s) = -0.42, P PETS, content analysis of free text responses suggested that the main barrier was a perceived lack of time to implement new skills. Facilitators included seeing the benefits of using the skills, finding opportunities and having good relationships with parents. Understanding the range of barriers and facilitators to implementation is essential when developing training to facilitate ongoing support and sustain skill use. Special attention should be given to exploring trainees' perceptions of time, to be able to address this significant barrier to skill implementation. Staff training requires a multi-faceted approach to address the range of perceived barriers. © 2012 Blackwell Publishing Ltd.

  7. Hindering the strand passage reaction of human topoisomerase IIalpha without disturbing DNA cleavage, ATP hydrolysis, or the operation of the N-terminal clamp

    DEFF Research Database (Denmark)

    Oestergaard, Vibe H; Giangiacomo, Laura; Bjergbaek, Lotte

    2004-01-01

    DNA topoisomerase II is an essential enzyme that releases a topological strain in DNA by introduction of transient breaks in one DNA helix through which another helix is passed. While changing DNA topology, ATP is required to drive the enzyme through a series of conformational changes dependent...

  8. Iontophoretic permeability of polyethylene glycols through hairless rat skin: application of hydrodynamic theory for hindered transport through liquid-filled pores.

    Science.gov (United States)

    Ruddy, S B; Hadzija, B W

    1992-02-01

    The electrically-assisted transport of a homologous series of polyethylene glycols (PEGs) through hairless rat skin (HRS) was examined in order to determine the relationship between the iontophoretic permeability of flexible macromolecules and their size and conformation in free solution. Using fully hydrated HRS, the anodic transport of 26 low molecular weight oligomers of PEG was studied over a 14 hour period at a current density of 0.50 mA/cm2. Analysis of the data revealed a distinct sigmoidal relationship between iontophoretic permeability and molecular size. In addition, the reflection of a relatively small molecular weight species was significant. Accordingly, a hydrodynamic model relating the convective transport of flexible macrosolutes through cylindrical pores was fit to the data generated from the iontophoretic transport of PEGs ranging in weight from 282 to 1382 daltons. A nonlinear least squares analysis of the data demonstrated that the 'effective' mean diameter of aqueous channels within HRS is approximately 36 A.

  9. Striving for Excellence Sometimes Hinders High Achievers: Performance-Approach Goals Deplete Arithmetical Performance in Students with High Working Memory Capacity.

    Directory of Open Access Journals (Sweden)

    Marie Crouzevialle

    Full Text Available We tested whether the goal to attain normative superiority over other students, referred to as performance-approach goals, is particularly distractive for high-Working Memory Capacity (WMC students-that is, those who are used to being high achievers. Indeed, WMC is positively related to high-order cognitive performance and academic success, a record of success that confers benefits on high-WMC as compared to low-WMC students. We tested whether such benefits may turn out to be a burden under performance-approach goal pursuit. Indeed, for high achievers, aiming to rise above others may represent an opportunity to reaffirm their positive status-a stake susceptible to trigger disruptive outcome concerns that interfere with task processing. Results revealed that with performance-approach goals-as compared to goals with no emphasis on social comparison-the higher the students' WMC, the lower their performance at a complex arithmetic task (Experiment 1. Crucially, this pattern appeared to be driven by uncertainty regarding the chances to outclass others (Experiment 2. Moreover, an accessibility measure suggested the mediational role played by status-related concerns in the observed disruption of performance. We discuss why high-stake situations can paradoxically lead high-achievers to sub-optimally perform when high-order cognitive performance is at play.

  10. Striving for Excellence Sometimes Hinders High Achievers: Performance-Approach Goals Deplete Arithmetical Performance in Students with High Working Memory Capacity.

    Science.gov (United States)

    Crouzevialle, Marie; Smeding, Annique; Butera, Fabrizio

    2015-01-01

    We tested whether the goal to attain normative superiority over other students, referred to as performance-approach goals, is particularly distractive for high-Working Memory Capacity (WMC) students-that is, those who are used to being high achievers. Indeed, WMC is positively related to high-order cognitive performance and academic success, a record of success that confers benefits on high-WMC as compared to low-WMC students. We tested whether such benefits may turn out to be a burden under performance-approach goal pursuit. Indeed, for high achievers, aiming to rise above others may represent an opportunity to reaffirm their positive status-a stake susceptible to trigger disruptive outcome concerns that interfere with task processing. Results revealed that with performance-approach goals-as compared to goals with no emphasis on social comparison-the higher the students' WMC, the lower their performance at a complex arithmetic task (Experiment 1). Crucially, this pattern appeared to be driven by uncertainty regarding the chances to outclass others (Experiment 2). Moreover, an accessibility measure suggested the mediational role played by status-related concerns in the observed disruption of performance. We discuss why high-stake situations can paradoxically lead high-achievers to sub-optimally perform when high-order cognitive performance is at play.

  11. Delegering: möjligheter och hinder : hur delegering till icke-legitimerad personal påverkar sjuksköterskans professionsutövning

    OpenAIRE

    Kindberg Jönsson, Caroline; Rosén, Moana

    2013-01-01

    Bakgrund: Delegering av hälso- och sjukvårdsuppgifter från legitimerad sjuksköterska till icke-legitimerad personal är vanlig. Tidigare forskning har visat att delegering kan leda till att sjuksköterskans roll blir otydlig. Syfte: Att undersöka hur sjuksköterskors professionsutövning påverkas av att delegering till icke-legitimerad personal förekommer. Metod: Tio vetenskapliga artiklar studerades enligt metod för kvalitativ innehållsanalys. Resultat: Tre huvudteman framstod: ”Sjuksköterskor o...

  12. Hypercoordinate β-carbon in Grubbs and Schrock olefin metathesis metallacycles.

    Science.gov (United States)

    Remya, Premaja R; Suresh, Cherumuttathu H

    2015-10-28

    Metallacyclobutane (MCB) intermediates of Grubbs and Schrock olefin metathesis catalysts are well-known for their unusually short single bond-like metal to Cβ distance and unusually long CαCβ distances. From the analysis of structural, bond order, electron density and (13)C NMR data of a large variety of MCB systems, we show that the Cβ of the metallacycle possesses pentacoordinate geometry due to the agostic type interaction of the metal with the CαCβ bonds. The pentacoordination of Cβ to the metal center is characterized by a catastrophe ring critical point (RCP) in the quantum theory of atoms-in-molecule (QTAIM) analysis. Fine tuning of the ligand environment changes the catastrophe point to a fifth bond critical point (BCP) which is clearly brought out in the case of two ruthenium olefin metathesis systems. Several Ru and W agostic MCB complexes exhibiting pentacoordinate Cβ as well as their non-agostic isomers have been reported at the BP86/def2-TZVPP level of DFT. The agostic systems showed a significant bond order between metal and Cβ (0.17-0.36), single bond-like electron density values at the catastrophe RCP/BCP and a significantly large difference in (13)C NMR chemical shift values between Cα and Cβ atoms.

  13. Neutron Diffraction Characterization of C–H···Li Interactions in a Lithium Aluminate Polymer

    Energy Technology Data Exchange (ETDEWEB)

    Cole, Jacqueline M.; Waddell, Paul G.; Wheatley, Andrew E. H.; McIntyre, Garry J.; Peel, Andrew J.; Tate, Christopher W.; Linton, David J.

    2014-08-11

    The reaction of AlMe3 with tBuLi in the presence of trimethylacetonitrile affords the bimetallic complex [tBu(Me)Al(μ-Me)2Li·NC(tBu)]∞ (1). Pseudotetrahedral Al centers form by the nucelophilic addition of tBuLi to AlMe3.The alkali-metal center is stabilized through coordination of the unreacted nitrile and polymer formation via the construction of Al(μ-Me)nLi (n = 1, 2) motifs. Neutron diffraction evidences agostic interactions in the bridging methyl group to give further stabilization. There is only one previous report of a neutron structure of a lithium aluminate compound. This work therefore offers an important structural example of agostic interactions and the precise nature of Al(μ-Me)2Li bridging.

  14. Health system’s barriers hindering implementation of public-private partnership at the district level: a case study of partnership for improved reproductive and child health services provision in Tanzania

    Directory of Open Access Journals (Sweden)

    Denice Kamugumya

    2016-10-01

    Full Text Available Abstract Background Public-private partnership (PPP has been suggested as a tool to assist governments in lower to middle income countries fulfil their responsibilities in the efficient delivery of health services. In Tanzania, although the idea of PPP has existed for many years in the health sector, there has been limited coordination, especially at a district level – which has contributed to limited health gains or systems strengthening obviously seen as a result of PPP. Methods This case study was conducted in the Bagamoyo district of Tanzania, and employed in-depth interviews, document reviews, and observations methods. A stakeholder analysis was conducted to understand power distribution and the interests of local actors to engage non-state actors. In total 30 in-depth interviews were conducted with key informants that were identified from a stakeholder mapping activity. The initial data analysis guided further data collection in an iterative process. The provision of Reproductive and Child Health Services was used as a context. This study draws on the decision-space framework. Results Study findings reveal several forms of informal partnerships, and the untapped potential of non-state actors. Lack of formal contractual agreements with private providers including facilities that receive subsidies from the government is argued to contribute to inappropriate distribution of risk and reward leading to moral hazards. Furthermore, findings highlight weak capacity of governing bodies to exercise oversight and sanctions, which is acerbated by weak accountability linkages and power differences. Disempowered Council Health Services Board, in relation to engaging non-state actors, is shown to impede PPP initiatives. Conclusion Effective PPP policy implementation at a local level depends on the capacity of local government officials to make choices that would embrace relational elements dynamics in strategic plans. Orientation towards collaborative efforts that create value and enable its distribution is argued to facilitate healthy partnership, and in return, strengthen a district health system. This study highlights a need for new social contracts that will support integrative collaboration at the local level and bring all non-state actors to the centre of the district health system.

  15. Las organizaciones ¿favorecen o dificultan una práctica enfermera basada en la evidencia? Health care organizations: favouring or hindering the practise of evidence based nursing?

    Directory of Open Access Journals (Sweden)

    Joan Ernest de Pedro Gómez

    2004-06-01

    Full Text Available El Artículo pretende desde una mirada crítica reflexionar sobre la posición e influencia de las organizaciones, respecto al desarrollo en la práctica clínica de los cuidados enfermeros. Es mucha la evidencia y son muchas las razones para demandar de las organizaciones, un posicionamiento que favorezca el cambio en los Modelos de Práctica Enfermera (MPE. Dada la influencia que tienen los cuidados en los resultados del proceso clínico (morbi-moratlidad y entendiendo éste como el objetivo de las organizaciones sanitarias, parece lógico intentar que las estructuras organizativas abandonen procesos asistenciales totalmente desfasados, para ofrecer los mejores servicios de salud. Para ello es necesario aplicar los resultados de investigación, tanto en la dotación de enfermeras como en la definición de servicios y cuidados enfermeros. Son las organizaciones las que deben establecer las condiciones para que las Enfermeras actúen en un plano de colaboración con otros profesionales y no de sumisión, posición desde la cual no pueden desarrollar su potencial profesional, el cual resulta necesario para un cambio de la prestación de servicios, adaptando éste a las demandas existentes. Sin la adecuada gestión, encaminada a la utilización del conocimiento enfermero como valor organizacional, será imposible adaptar las necesidades de cuidados a las demandas de servicios. Las organizaciones deben optar por un servicio en el que el MPE permita la inclusión de aquellos resultados de investigación con notables efectos en la calidad de sus procesos, las organizaciones deben asumir la responsabilidad de actuar bajo un modelo, que a todas luces no puede ser otro que el de aplicar en la práctica clínica las evidencias producidas por la investigación.This paper is intended to provide a critical reflection about how organizations influence the nursing clinical practice development. There is an increasing evidence in nursing science and a positioning of Health care Organizations is needed for promoting a statement in order to change the current nursing practice models, because of their impact on health outcomes. Health Organizations have to leave out of date practice models that do not help to excellence in nursing. Research results implementation is a crucial issue in this purpose, for a better defining of nursing services and human resources. Health Organizations must establish the conditions for an integrated care model, with symmetric collaboration among professionals. If this position is not reached, the nursing potential can be underestimated and underdeveloped, precisely, in a continuous changing environment, with raising demands on health and dependency. Health Organizations must be directed to nursing practice models implementation research-orientated, supported in evidence-based nursing, as essential component of quality of care.

  16. What helps and hinders midwives in engaging with pregnant women about stopping smoking? A cross-sectional survey of perceived implementation difficulties among midwives in the North East of England

    Directory of Open Access Journals (Sweden)

    Beenstock Jane

    2012-04-01

    Full Text Available Abstract Background Around 5,000 miscarriages and 300 perinatal deaths per year result from maternal smoking in the United Kingdom. In the northeast of England, 22% of women smoke at delivery compared to 14% nationally. Midwives have designated responsibilities to help pregnant women stop smoking. We aimed to assess perceived implementation difficulties regarding midwives’ roles in smoking cessation in pregnancy. Methods A self-completed, anonymous survey was sent to all midwives in northeast England (n = 1,358 that explores the theoretical explanations for implementation difficulties of four behaviours recommended in the National Institute for Health and Clinical Excellence (NICE guidance: (a asking a pregnant woman about her smoking behaviour, (b referring to the stop-smoking service, (c giving advice about smoking behaviour, and (d using a carbon monoxide monitor. Questions covering Michie et al.’s theoretical domain framework (TDF, describing 11 domains of hypothesised behavioural determinants (i.e., ‘knowledge’, ‘skills’, ‘social/professional role/identity’, ‘beliefs about capabilities’, ‘beliefs about consequences’, ‘motivation and goals’, ‘memory’, ‘attention and decision processes’, ‘environmental context and resources’, ‘social influences’, ‘emotion’, and ‘self-regulation/action planning’, were used to describe perceived implementation difficulties, predict self-reported implementation behaviours, and explore relationships with demographic and professional variables. Results The overall response rate was 43% (n = 589. The number of questionnaires analysed was 364, following removal of the delivery-unit midwives, who are not directly involved in providing smoking-cessation services. Participants reported few implementation difficulties, high levels of motivation for all four behaviours and identified smoking-cessation work with their role. Midwives were less certain about the consequences of, and the environmental context and resources available for, engaging in this work relative to other TDF domains. All domains were highly correlated. A principal component analysis showed that a single factor (‘propensity to act’, derived from all domains, explained 66% of variance in theoretical domain measures. The ‘propensity to act’ was predictive of the self-reported behaviour ‘Refer all women who smoke……to NHS Stop Smoking Services’ and mediated the relationship between demographic variables, such as midwives’ main place of work, and behaviour. Conclusions Our findings advance understanding of what facilitates and inhibits midwives’ guideline implementation behaviours in relation to smoking cessation and will inform the development of current practice and new interventions. Using the TDF as a self-completion questionnaire is innovative, and this study supports previous research that the TDF is an appropriate tool to understand the behaviour of healthcare professionals.

  17. Sterically hindered complexes of platinum(II) with planar heterocyclic nitrogen donors. A novel complex with 1-methyl-cytosine has a spectrum of activity different from cisplatin and is able of overcoming acquired cisplatin resistance.

    Science.gov (United States)

    Margiotta, Nicola; Natile, Giovanni; Capitelli, Francesco; Fanizzi, Francesco P; Boccarelli, Angelina; De Rinaldis, Pietro; Giordano, Domenico; Coluccia, Mauro

    2006-11-01

    A very interesting series of water soluble platinum compounds violating some of the classical structure-activity relationships, but still showing antitumor activity, was reported by Hollis and collaborators some 25 years ago [L.S. Hollis, A.R. Amundsenm, E.W. Stern. J. Med. Chem. 32 (1989) 128-136]. The compounds, having formula [PtClA(2)L](+) (A(2)=two monodentate or a bidentate amine, L=a secondary or tertiary amine or a N-donor heterocycle), were characterized by a positive charge and three non-labile N-donor ligands. We have extended the investigation to analogous compounds in which 2,9-dimethyl-1,10-phenanthroline has taken the place of the A(2) ligand(s) and L is 2-picoline (1), 6-amino-2-picoline (2), or 1-methyl-cytosine (3). The X-ray analysis of 2 has revealed a bow-like distortion of the phenanthroline plane, a sloping of the phenanthroline plane with respect to the coordination plane, and an overall shielding of the metallic core by the ortho substituents of the phenanthroline and pyridine ligands. In vitro grow inhibition assays have been performed on the most water soluble complex 3. The results indicate that this complex is characterized by a potent growth inhibitory activity with mean IC(50) value (in a panel of 11 human tumor cell lines) of 1.1 microM to be compared with a mean value of 3.8 microM for cisplatin. The same compound also appears to completely overcome the acquired cisplatin resistance stemming from reduced uptake or a multifocal mechanism, thus pointing to a mechanism of action distinctly different from that of cisplatin.

  18. What are some of the cognitive, psychological, and social factors that facilitate or hinder licensed vocational nursing students' acquisition of problem-solving skills involved with medication-dosage calculations?

    Science.gov (United States)

    Allen, Arthur William

    The purpose of this study was to examine the cognitive and psychological factors that either enhanced or inhibited Licensed Vocational Nurse (LVN) students' abilities to solve medication-dosage calculation problems. A causal-comparative approach was adopted for use in this study which encompassed aspects of both qualitative and quantitative data collection. A purposive, maximum-variation sample of 20 LVN students was chosen from among a self-selected population of junior college LVN students. The participants' views and feelings concerning their training and clinical experiences in medication administration was explored using a semi-structured interview. In addition, data revealing the students' actual competence at solving sample medication-dosage calculation problems was gathered using a talk-aloud protocol. Results indicated that few participants anticipated difficulty with medication-dosage calculations, yet many participants reported being lost during much of the medication-dosage problem solving instruction in class. While many participants (65%) were able to solve the medication-dosage problems, some (35%) of the participants were unable to correctly solve the problems. Successful students usually spent time analyzing the problem and planning a solution path, and they tended to solve the problem faster than did unsuccessful participants. Successful participants relied on a formula or a proportional statement to solve the problem. They recognized conversion problems as a two-step process and solved the problems in that fashion. Unsuccessful participants often went directly from reading the problem statement to attempts at implementing vague plans. Some unsuccessful participants finished quickly because they just gave up. Others spent considerable time backtracking by rereading the problem and participating in aimless exploration of the problem space. When unsuccessful participants tried to use a formula or a proportion, they were unsure of the formula's or the proportion's format. A few unsuccessful participants lacked an understanding of basic algebraic procedures and of metric measurements. Even participants who had great difficulty solving medication-dosage calculation problems could expeditiously solve more complex problems if the medication used in the problem was well known to them.

  19. Anti-HER3 Domain 1 and 3 Antibodies Reduce Tumor Growth by Hindering HER2/HER3 Dimerization and AKT-Induced MDM2, XIAP, and FoxO1 Phosphorylation

    Directory of Open Access Journals (Sweden)

    Yassamine Lazrek

    2013-03-01

    Full Text Available Blockade of the human epidermal growth factor receptor 3 (HER3 and of the downstream phosphatidylinositide 3-kinase (PI3K/AKT pathway is a prerequisite for overcoming drug resistance and to develop novel treatments for cancers that are not eligible for the currently approved targeted therapies. To this end, we generated specific antibodies (Abs against domain 1 (D1 and domain 3 (D3 of HER3 that recognize epitopes that do not overlap with the neuregulin-binding site. The fully human H4B-121 Ab and the mouse monoclonal Abs 16D3-C1 and 9F7-F11 inhibited tumor growth in nude mice xenografted with epidermoid, pancreatic, or triple-negative breast cancer cells. The combination of one anti-HER3 Ab and trastuzumab improved tumor growth inhibition in mice xenografted with HER2low cancer cell lines, for which trastuzumab alone shows no or moderate efficiency. Ab-induced disruption of tumor growth was associated with G1 cell cycle arrest, proliferation inhibition, and apoptosis of cancer cells. Anti-HER3 Abs blocked HER2/HER3 heterodimerization and HER3 phosphorylation at the cell membrane, leading to inhibition of phosphorylation of the downstream AKT targets murine double minute 2, X-linked inhibitor of apoptosis, and forkhead box O1. This study demonstrates that anti-HER3 D1 and D3 Abs could represent a new option for immunotherapy of pancreatic and triple-negative breast cancers.

  20. Investigacion educativa. El sistema escolar en sus diferentes niveles, factores que favorecen o frenan su eficacia y medidas de superacion (Educational Research. The Educational System at Different Levels; Factors Promoting or Hindering Its Efficiency; Possible Improvements.

    Science.gov (United States)

    Jimenez Lozano, Blanca; And Others

    This document is an English-language abstract (Approximately 1,500 words) of a study on educational research in Mexico. Chapter one discusses the importance of educational research, in terms of its role both in scientific and technical development; it should use scientific methods so that it will have solid foundations. Chapter two is a survey of…

  1. Lack of political leadership hinders energy transition. The necessity of cooperation between market parties. Special on Energy Transition; Gemis aan politiek leiderschap belemmert energietransitie. Samenwerking tussen marktpartijen noodzakelijk. Themanummer Energietransitie

    Energy Technology Data Exchange (ETDEWEB)

    Van Mil, R. (ed.)

    2008-10-15

    Energy use in the Netherlands must be reduced significantly and the use of sustainable energy increased quickly in order to realize the ambitious targets of 20% sustainable energy in 2020, among other things. Five experts who are involved in the energy transition trajectory consider the targets feasible, but they miss government leadership. [mk]. [Dutch] Het energiegebruik in Nederland moet sterk omlaag en het gebruik van duurzame energie snel omhoog om de ambitieuze doelstellingen van onder meer 20 procent duurzame energie in 2020 te realiseren. Vijf experts die betrokken zijn bij het energietransitietraject vinden de doelstellingen haalbaar, maar missen leiderschap van de overheid.

  2. Noninnocent Proton-Responsive Ligand Facilitates Reductive Deprotonation and Hinders CO2 Reduction Catalysis in [Ru(tpy)(6DHBP)(NCCH3)](2+) (6DHBP = 6,6'-(OH)2bpy).

    Science.gov (United States)

    Duan, Lele; Manbeck, Gerald F; Kowalczyk, Marta; Szalda, David J; Muckerman, James T; Himeda, Yuichiro; Fujita, Etsuko

    2016-05-02

    Ruthenium complexes with proton-responsive ligands [Ru(tpy)(nDHBP)(NCCH3)](CF3SO3)2 (tpy = 2,2':6',2″-terpyridine; nDHBP = n,n'-dihydroxy-2,2'-bipyridine, n = 4 or 6) were examined for reductive chemistry and as catalysts for CO2 reduction. Electrochemical reduction of [Ru(tpy)(nDHBP)(NCCH3)](2+) generates deprotonated species through interligand electron transfer in which the initially formed tpy radical anion reacts with a proton source to produce singly and doubly deprotonated complexes that are identical to those obtained by base titration. A third reduction (i.e., reduction of [Ru(tpy)(nDHBP-2H(+))](0)) triggers catalysis of CO2 reduction; however, the catalytic efficiency is strikingly lower than that of unsubstituted [Ru(tpy)(bpy)(NCCH3)](2+) (bpy = 2,2'-bipyridine). Cyclic voltammetry, bulk electrolysis, and spectroelectrochemical infrared experiments suggest the reactivity of CO2 at both the Ru center and the deprotonated quinone-type ligand. The Ru carbonyl formed by the intermediacy of a metallocarboxylic acid is stable against reduction, and mass spectrometry analysis of this product indicates the presence of two carbonates formed by the reaction of DHBP-2H(+) with CO2.

  3. Mechanism for the exchange processes observed in the compounds [M({eta}-C{sub 5}H{sub 5}){sub 2}({eta}-RCH=CH{sub 2})H] (M = Nb, Ta)

    Energy Technology Data Exchange (ETDEWEB)

    Green, M.L.H.; Wong, Luet-Lok [Inorganic Chemistry Lab., Oxford (United Kingdom); Sella, A. [Univ. College, London (United Kingdom)

    1992-07-01

    The fluxional processes in the compounds exo-[M({eta}-C{sub 5}H{sub 5}){sub 2}({eta}CH{sub 3}CH=CH{sub 2})H] (M = Nb, Ta) have been investigated by magnetization and spin-saturation transfer and two-dimensional exchange NMR techniques. Rate constants for three separate processes have been determined. A mechanism involving agostic {eta}{sup 2}-alkyl ligands is proposed. 62 refs., 11 figs., 2 tabs.

  4. Stratigraphic and paleogeographic correlation between the Tethys and the Atlantic realms across the Cretaceous-Paleogene transition: Tunisia, Spain and France

    Science.gov (United States)

    Gallala, N.; Zaghbib-Turki, D.; Turki, M. M.; Arenillas, I.; Arz, J. A.; Molina, E.

    2009-04-01

    Based on the high resolution biostratigraphical analysis, the El Kef (K/Pg boundary stratotype section and GSSP point) and Ellès sections (Tunisia) and the Agost and Caravaca sections (Betic cordillera, Spain), located at Tethyan realms, are showing a complete section in its Cretaceous-Paleogene transition interval may be compared with their neighbors in the Atlantic realm (Bidart section, SW France). At the Tethys realm, all the biozones and subzones are easily recognized by their biomarkers. Even the uppermost Maastrichtian is developed and indicated by P. hantkeninoides. This biomarker is absent at the Atlantic section of middle latitude: (Bidart, SW France). This later are characterized by P. hariaensis biomarker which have larger paleogeographic extension, it is why we have choose to consider this late species as indicator of the uppermost Cretaceous subzone at Atlantic realm and the P. hantkeninoides as indicator of Tethys realm. At El Kef section, the G. cretacea biozone spans 55 cm. It is more expanded than at Agost (12,5 cm), Caravaca (15 cm) relative to the Tethys realm, and to Bidart (10 cm) relative to Atlantic realm but it is nearly expanded than at Ellès section in Tunisia (66 cm). In spite of the reduced G. cretacea biozone expansion at El Kef K/Pg boundary stratotype and the auxiliary sections, Caravaca and Agost sections (Spain), like as elsewhere, at the Bidart (France) and the Ellès section (Tunisia), the Pv. longiapertura FAD is observed at the upper part of the relevant biozone. At the El Kef section the Pv. eugubina zone spans 5.7 m, it is largely expanded than at Caravaca and Agost sections spanning respectively (42 cm and 65 cm), it is also more expanded than at Bidart section (SW France) spanning 107 cm. But it is approximately equivalent than Elles (5.8 m). This zone is subdivided into Pv. sabina and E. simplicissima subzones. The deposition thickness of the zones and subzones are less expanded than at El Kef and Elles sections. This

  5. Estudio de la inactivación por ultra alta presión de homogeneización de microorganismos en alimentos líquidos valoración de los procesos de limpieza y desinfección del equipo /

    OpenAIRE

    Briñez Zambrano, Wilfido José

    2006-01-01

    Descripció del recurs: el 31 d'agost 2006 Consultable des del TDX El objetivo principal de esta Tesis Doctoral fue evaluar la inactivación bacteriana usando Ultra Alta Presión de Homogeneización (UHPH) a 300 + 30 MPa de las cepas Listeria innocua ATCC 33090, Escherichia coli ATCC 10536, Escherichia coli O157:H7 CCUG 44857, Staphylococcus aureus ATCC 13565 y Staphylococcus carnosus CECT 4491 inoculadas en leche entera, leche desnatada y zumo de naranja. También, intentamos estudiar el ef...

  6. Efecto de la implantación angulada o transversa con flexión de las agujas transfixiantes sobre la cicatrización de osteotomias tibiales en perro reducidas mediante fijadores externos

    OpenAIRE

    Franch Serracanta, Jordi

    2008-01-01

    Descripció del recurs: el 26 d'agost de 2008 Consultable des del TDX Títol obtingut de la portada digitalitzada Se ha realizado un trabajo experimental en veintidós perros en los que se estudio la cicatrización de osteotomias tibiales. Los objetivos principales eran evaluar el efecto que tenían sobre la cicatrización, la implantación angulada o transversal de los fijadores así como el desplazamiento lateral de éstos. Se controló el proceso de cicatrización ósea por radiología, gammag...

  7. Avances en el desarrollo de bioprocesos: adición aldólica catalizada por ramnulosa-1-fosfato aldolasa recombinante

    OpenAIRE

    Ardao Palacios, Inés

    2009-01-01

    Descripció del recurs: el 10 d'agost de 2010 En la actualidad existe un creciente interés en el desarrollo de procesos industriales biocatalíticos eficientes desde el punto de vista económico y medioambiental. Uno de los procesos más prometedores para la industria es la biocatálisis de la formación de enlaces C-C para la producción de compuestos de estereoquímica definida, de aplicación en diversos campos y, en especial, en la industria farmacéutica. El presente trabajo de Tesis Doctoral e...

  8. En California dos pioneros: Uno en el pasado y otro en el presente

    Directory of Open Access Journals (Sweden)

    Mauricio Bermúdez

    2002-11-01

    Full Text Available Agost on Haraszthy buscando un clima para alivio de su enfermedad arribó en 1849 al sur de California donde se convirtió en el pionero al importar, sembrar y producir vino con Zinfandel, una entre otras muchas vides europeas. Construyó el viñedo Buena Vista diseñado para esa época con las mejores facilidades, no obstante, la empresa estaba destinada al colapso financiero por el incumplimiento del Estado de California; la vida de Agost on fue una aventura y tras su muerte una leyenda. En 1976 Peter Haywood decide cambiar su vida dedicada a las finanzas, deja Nueva York y viaja a California, allí compra un terreno para adecuarlo como viñedo; en 1980 obtiene su primera producción comercial y gracias a la fuerte demanda se vio obligado a incrementar su producción. El Zinfandel producido en el viñedo los Chamizales de la casa Haywood ha sido galardonado y declarado como el mejor. ¿Cuáles serán las caracte-rísticas del vino para lograr esa gran acogida?

  9. A DFT Study on Selected Physical Organic Aspects of the Fischer Carbene Intermediates [(M(CO4(C(OMeMe

    Directory of Open Access Journals (Sweden)

    Tareq Irshaidat

    2010-01-01

    Full Text Available Fischer carbenes are important starting materials for C-C bond formation via coupling reactions between carbene and wide variety of substituted alkenes or alkynes. This DFT study shed light on unique fundamental organic/organometallic aspects for the C(OMeMe carbene in the free form and in case of bonding with M(CO4 (M= Cr, Mo, W. The data illustrate that the structures of the title intermediates include a unique structure stabilizing intramolecular M…C-H interaction (agostic interaction. This conclusion was made based on calculated NMR data (for carbon and hydrogen, structural parameters, energy calculations of conformers (C-C conformation, selected IR stretching frequencies (C-O, C-C, and C-H, and atomic charges. The agostic interaction is most efficient in case of chromium and in general is described as an overlap between the σ-bond electron pair of C-H with an empty d-orbital of the metal. These characterized examples are new addition to the orbital interaction theory.

  10. Gas-phase reactivity of lactones: structure and stability of their Cu+ complexes

    Science.gov (United States)

    Esseffar, M.; Mó, O.; Yáñez, M.

    2003-01-01

    The structure and relative stability of different lactone-Cu+ complexes, including cycles changing from four to six-membered rings, have been investigated through the use of density functional theory methods. The geometries and vibrational frequencies were calculated at the B3LYP/6-311G(d,p) level. Final energies were obtained in single point calculations carried out at the B3LYP/6-311 + G(2df,2p) level of theory. Upon interaction with Cu+ in the gas phase, lactones behave in a rather similar way as they do in protonation processes. Systematically the global minimum of the potential energy surface corresponds to the attachment of the metal cation to the carbonyl oxygen cis with respect to the ether-like oxygen. Also, similarly to proton affinities, the calculated Cu+ binding energies increase with the size of the system. The unsaturated compounds are found to be only slightly more basic than the saturated counterparts. Cu+ attachment leads to significant bond activation and bond reinforcement effects, reflected in redshiftings and blueshiftings of the stretching frequencies, respectively. Cu+ is able to form agostic bonds with some of the CH2 groups of the lactone moiety. These agostic complexes can be good precursors for the unimolecular loss of H2, which very likely should be observed in the mass spectra.

  11. Use and Access of Grey Literature in Special Libraries may be Hindered by Lack of Visibility and Cataloguing. A review of: Ranger, Sara L. “Grey Literature in Special Libraries: Access in Use.” Publishing Research Quarterly 21.1 (Spring 2005: 53-63.

    Directory of Open Access Journals (Sweden)

    David Hook

    2006-03-01

    Full Text Available Objective – To examine the barriers to making grey literature (literature not controlled by commercial publishers easier to access in special libraries. Design – Interviews. Setting – Variety of special libraries (government, corporate and specialized academic in the United States. Subjects – Sixteen librarians from fourteen organizations in Washington, Michigan and Texas were interviewed. Four of the organizations were government libraries, four were corporate libraries and five were specialized academic libraries. One of the interviews was not used because the organization did not maintain a collection of paper‐based grey literature. Methods – Librarians were selected as possible interview subjects via three methods: some were previously familiar with the author; some were referred to the author by friends, family and colleagues; two candidates volunteered in response to a presentation of the project at a professional meeting. Interviews were conducted between February 2002 and May 2003. A standard set of seven questions were used, but often followed with further questions. The interviews were conducted either in the library or the librarian’s office. The interviews were tape‐recorded and the answers were written down. Interviews typically lasted between fifteen and thirty minutes and asked about the current state, holdings, access and use of grey literature in the special library. Main Results – Results from the interviews suggest a wide variance in the percentage of users that access grey literature. Grey literature was used less in the corporate libraries than the academic and government libraries. The percentage of the collection made up of grey literature also varied widely between the different libraries. Reports were found to be the most popular form of grey literature, although most of the libraries reported owning conference proceedings and newsletters in addition to reports. One interesting observation found during the interviews was that most of the users of grey literature are also producers of grey literature. The librarians surveyed reported that some of the reasons for using grey literature included use in research, to write (often more grey literature, interest in the topic, for class assignments, as records of previous practices, for localized studies, and for creating models and practices. Results found that for the libraries surveyed, much of the grey literature remains uncatalogued and what has been catalogued was done using a variety of methods. Over half of the libraries surveyed had their grey literature accessible online. Conclusion – Two main reasons were cited as explanations for why grey literature was not used as much as it should be: lack of cataloguing and visibility. In many of the libraries surveyed, much of the grey literature had not been catalogued, making it difficult to find and use the resources. Reasons cited for not cataloguing grey literature include lack of time, funds and/or knowledge. As well, in many of the libraries surveyed, it was found that the holdings of grey literature were not readily visible to the users, so users were not even aware that it existed. To improve the awareness and accessibility of grey literature, the author recommends regional depositories for grey literature, international standards for cataloguing and more cooperation between special libraries.

  12. Språk och minne – hinder eller verktyg? : En studie om pedagogers förhållningssätt till elever med språkstörning i lärandesituationer, med fokus på arbetsminne

    OpenAIRE

    Karlberg, Anna

    2015-01-01

    The purpose of this study is to generate knowledge about how teachers relate to students with language impairment in learning situations, with particular focus on working memory. The questions are: What kind of knowledge do teachers have regarding language impairment and working memory?, What experience do teachers have regarding lack of working memory abilities among students with language impairment and which consequences do the teachers believe such defects may have for the students? and H...

  13. X-ray crystal structures of the pheromone-binding domains of two quorum-hindered transcription factors, YenR of Yersinia enterocolitica and CepR2 of Burkholderia cenocepacia: KIM et al.

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Youngchang [Midwest Center for Structural Genomics, Biosciences, Argonne National Laboratory, Argonne Illinois 60439; Structural Biology Center, Biosciences, Argonne National Laboratory, Argonne Illinois 60439; Chhor, Gekleng [Midwest Center for Structural Genomics, Biosciences, Argonne National Laboratory, Argonne Illinois 60439; Tsai, Ching-Sung [Department of Microbiology, Cornell University, Ithaca New York 14853; Fox, Gabriel [Department of Microbiology, Cornell University, Ithaca New York 14853; Chen, Chia-Sui [Department of Microbiology, Cornell University, Ithaca New York 14853; Winans, Nathan J. [Department of Microbiology, Cornell University, Ithaca New York 14853; Jedrzejczak, Robert [Structural Biology Center, Biosciences, Argonne National Laboratory, Argonne Illinois 60439; Joachimiak, Andrzej [Midwest Center for Structural Genomics, Biosciences, Argonne National Laboratory, Argonne Illinois 60439; Structural Biology Center, Biosciences, Argonne National Laboratory, Argonne Illinois 60439; Department of Biochemistry and Molecular Biology, University of Chicago, Chicago Illinois 60637; Winans, Stephen C. [Department of Microbiology, Cornell University, Ithaca New York 14853

    2017-07-24

    The ability of LuxR-type proteins to regulate transcription is controlled by bacterial pheromones, N-acylhomoserine lactones (AHLs). Most LuxR-family proteins require their cognate AHLs for activity, and some of them require AHLs for folding and stability, and for protease-resistance. However, a few members of this family are able to fold, dimerize, bind DNA, and regulate transcription in the absence of AHLs; moreover, these proteins are antagonized by their cognate AHLs. One such protein is YenR of Yersinia enterocolitica, which is antagonized by N-3-oxohexanoyl-l-homoserine lactone (OHHL). This pheromone is produced by the OHHL synthase, a product of the adjacent yenI gene. Another example is CepR2 of Burkholderia cenocepacia, which is antagonized by N-octanoyl-l-homoserine lactone (OHL), whose synthesis is directed by the cepI gene of the same bacterium. Here, we describe the high-resolution crystal structures of the AHL binding domains of YenR and CepR2. YenR was crystallized in the presence and absence of OHHL. While this ligand does not cause large scale changes in the YenR structure, it does alter the orientation of several highly conserved YenR residues within and near the pheromone-binding pocket, which in turn caused a significant movement of a surface-exposed loop.

  14. Vibrationally Resolved Spectra of C2-C11 by Anion Photoelectron Spectroscopy

    Science.gov (United States)

    1991-07-01

    Chem. Phys. Let. 173, 164 (1990). 17. (a) R. J. van Zee, R. F. Ferrante, K. J. Zeringue, W. Welmer , Jr., and D. W. Ewing, 3. Chem. Phys. 88, 3465 (1988...b) R. J. van Zee, R. F. Ferrante, K. J. Zeringue, and W. Welmer Jr., J. Chem. Phys. 86, 5212 (1987); (c) H. M. Cheung and W. R. M. Graham, J. Chem

  15. Industrial ecology as a discipline for the analysis and design of sustainable urban settlements

    OpenAIRE

    Oliver i Solà, Jordi

    2009-01-01

    Descripció del recurs: el 11 d'agost de 2010 Malgrat representar només el 2,7% de la superfície del planeta, les ciutats del món són responsables del 75% del consum d'energia, i el 80% de les emissions de gasos d'efecte hivernacle. Encara que el focus d'atenció per mitigar el canvi climàtic s'ha centrat en els combustibles alternatius, vehicles, i la generació d'electricitat; la millora del disseny urbà, representa una oportunitat important que sovint no es valora prou. Aquesta tesi estén ...

  16. De la perifèria al centre: el cas de 'Ferdydurke' de Witold Gombrowicz

    OpenAIRE

    Zaboklicka, Bozena

    2012-01-01

    Witold Gombrowicz arribà a Buenos Aires a bord del vaixell Chrobry el 22 d'agost de 1939. Uns dies després l'Alemanya nazi envaïa Polònia i Gombrowicz decidia quedar-se a l'Argentina, on romandria gairebé 24 anys. L'any 1947, després d'haver passat gairebé 10 anys sense escriure pràcticament res, decideix explicar la seva atípica arribada al país i les setmanes que seguiren. Però aquell Trans-Atlantyk ràpidament agafarà una altra destinació i retornarà l'autor cap a la seva terra nativa, conv...

  17. WITOLD GOMBROWICZ’S TRANS-ATLANTYK, A READING GUIDE FOR NON-POLISH READERS

    OpenAIRE

    FREIXA TERRADAS, PAU

    2013-01-01

    Witold Gombrowicz arribà a Buenos Aires a bord del vaixell Chrobry el 22 d’agost de 1939. Uns dies després l’Alemanya nazi envaïa Polònia i Gombrowicz decidia quedar-se a l’Argentina, on romandria gairebé 24 anys. L’any 1947, després d’haver passat gairebé 10 anys sense escriure pràcticament res, decideix explicar la seva atípica arribada al país i les setmanes que seguiren. Però aquell Trans-Atlantyk ràpidament agafarà una altra destinació i retornarà l’autor cap a la seva terra nativa, conv...

  18. Trans-Atlantyk de Witold Gombrowicz, guia de lectura per a no-polonesos

    OpenAIRE

    Freixa Terradas, Pau

    2012-01-01

    Witold Gombrowicz arribà a Buenos Aires a bord del vaixell Chrobry el 22 d'agost de 1939. Uns dies després l'Alemanya nazi envaïa Polònia i Gombrowicz decidia quedar-se a l'Argentina, on romandria gairebé 24 anys. L'any 1947, després d'haver passat gairebé 10 anys sense escriure pràcticament res, decideix explicar la seva atípica arribada al país i les setmanes que seguiren. Però aquell Trans-Atlantyk ràpidament agafarà una altra destinació i retornarà l'autor cap a la seva terra nativa, conv...

  19. Carbons and hydrogen by persistent metal radicals. Final report, April 1, 1993--October 31, 1994

    Energy Technology Data Exchange (ETDEWEB)

    1995-12-31

    The synthesis of complexed rhenium radicals is demonstrated from the reaction of sterically demanding phosphine with the triphenylmethyl complex [n{sup 5}-CPh{sub 3}]Re(CO){sub 3}. Low yields are experienced unless high concentrations of phosphine ligands are employed with the mechanism of this reaction yet unknown. A complexed rhenium dimer is also synthesized, but in low yield. X-ray crystallography reveals that the sixth coordination site of the electron deficient rhenium cation (an extremely strong Lewis acid) is occupied by an agostic interaction with one of the pendant C-H bonds of the cyclohexyl ring of the complex. Preliminary results show that the rhenium complexes have a significantly different chemistry from similar tungsten analogs in reactivity and isotope exchange rates. It is hypothesized that the rhenium complexes would be useful in catalyzing the isotope exchange between water and hydrogen.

  20. Caracterización fitosanitaria a roya café (Puccinia melanocephala) y carbón (Ustilago scitaminea) de 63 clones de caña de azúcar, en fases avanzadas de selección en México.

    OpenAIRE

    Hernández Soriano, José Luis

    2012-01-01

    Se llevó a cabo una caracterización fitosanitaria de 63 clones de caña de azúcar (Saccharum officinarum L.) en fases avanzadas de selección en México, fueron valoradas a las enfermedades de la roya café y carbón, bajo un diseño de bloques completos al azar con tres repeticiones y un surco de 5 m de largo sembrado a 1.4 m entre surcos como unidad experimental. La evaluación del experimento se realizó bajo condiciones de infección natural en campo, en ciclo plantilla (Agosto 2010) y soca (Agost...

  1. Alterações decorrentes do envelhecimento podem impedir a indetificação de indivíduos submetidos a radiografias da coluna lombar? Potencial contribuição da avaliação radiológica para a atividade forense Can changes associated with aging hinder the identification of individuals submitted to lumbar spine radiography? A potential contribution of radiology to the forensic activity

    Directory of Open Access Journals (Sweden)

    Sílvia Falcão de Oliveira

    2007-10-01

    Full Text Available OBJETIVO: O objetivo deste trabalho foi avaliar a possibilidade de o exame radiológico da coluna lombar determinar a identificação correta dos indivíduos, apesar das alterações evolutivas do envelhecimento. MATERIAIS E MÉTODOS: Foi constituída amostra com 60 pares de radiografias de coluna lombar, feitas em épocas distintas, com intervalo mínimo de três anos, de pacientes de ambos os sexos, adultos e com idades diversas. Os pares foram misturados para que dois experientes radiologistas os reconstituíssem. As vértebras de cada par foram comparadas em relação a semelhanças e diferenças de detalhes anatômicos, sendo estabelecido, como critério de pareamento, o encontro de uma variação anatômica ou de uma particularidade específica, ou o encontro de duas ou mais igualdades entre os detalhes anatômicos, sem pontos de divergência. RESULTADOS: O correto pareamento de todas as radiografias foi alcançado por ambos os observadores, os quais apresentaram inúmeros pontos de coincidência em suas análises. O estudo estatístico demonstrou que a concordância entre os dois observadores foi considerada de boa a perfeita. CONCLUSÃO: A comparação radiográfica da coluna lombar é capaz de determinar a correta identificação dos indivíduos, apesar das alterações evolutivas do envelhecimento. Dessa forma, as radiografias representam potencial instrumento para uso em perícias de identificação forense.OBJECTIVE: The present study was aimed at evaluating the possibility of a radiological study of the lumbar spine determining the correct identification of an individual despite the changes associated with aging. MATERIALS AND METHODS: The study sample included 60 pairs of lumbar spine radiographic images of both male and female, adult patients of different ages, acquired at different times, at three-year minimum intervals. The pairs of images were mixed up so two experienced radiologists could put them back together. The vertebrae of each pair were compared for similarities and differences in anatomical details. Pairing criteria adopted were finding a specific anatomical variation or detail, or finding two or more similarities among anatomical details, with no point of divergence. RESULTS: Correct pairing of radiographs of the whole sample was achieved by both observers, who presented countless coincidence points in their analyses. The statistical analysis demonstrated a good-to-perfect interobserver agreement. CONCLUSION: Comparison between radiographic images of lumbar spine can determine a correct identification of individuals, despite changes associated with aging. Therefore, radiography represents a potential tool to be utilized in forensic identification studies.

  2. The Roles of Discourse, Legitimacy and Power in Enabling and Hindering Institutional Change towards Sustainability : A dissertation submitted in partial fulfillment of the requirements for the degree of PHD in business administration and docteur en sciences de gestion de l'école doctorale EM2P - économie, management, mathématiques et physique n° 405 from Essec Business School

    OpenAIRE

    Etchanchu, Helen

    2016-01-01

    Despite increasing awareness and agreements to mitigate climate change, countries are slow to decrease their fossil fuel consumption. For example, the global financial crisis in 2008 led to a fall of natural gas consumption in OECD countries. However, the exploitation of unconventional hydrocarbon resources, such as shale gas, in the United States has significantly increased gas consumption again, showing strong economic, environmental, and political implications that challenge the energy sec...

  3. The ’New’ Law of the Sea and the Law of Armed Conflict at Sea

    Science.gov (United States)

    1992-10-01

    I The "New" Law of the Sea and The Law of Anned Conflict at Sea Horace B. Robertson, Jr. NAVAL WAR COLLEGE Newport, Rhode Island CENTER FOR...XIII and the LOS Convention. While acknowledging that the French text of the LOS Convention uses the tenns droit souverain and juridiction to...34 Northwestem Univ. LAw Review, V. 52, p. 320 Quly-August 1 957) . See also, C.H.M. Waldock, "The Release of the Altmark Prisoners , " British

  4. Trivalent metallocene chemistry of some uranium, titanium, and zirconium complexes

    Energy Technology Data Exchange (ETDEWEB)

    Lukens, Jr., Wayne Wendell [Univ. of California, Berkeley, CA (United States)

    1995-05-01

    Dicyclopentadienyluranium halide dimers have been prepared and their solution behavior examined. These molecules exist as dimers in solution, and the halide ligands undergo rapid site exchange on the NMR timescale above 50 C. Analogous dicyclopentadienyluranium hydroxide dimers have also been prepared; they oxidatively eliminate hydrogen to give the corresponding oxide dimers. Mechanism of this reaction is consistent with αmigration of one of the hydroxide hydrogen atoms to a uranium center followed by elimination of hydrogen. Ground state of [(Me3Si)2C5H3]3M M = Nd, U and their base adducts has been examined by variable temperature magnetic susceptibility and EPR spectroscopy. The ground state is found to be 4I9/2 with a crystal field state consisting largely of Jz = 1/2 lowest, in agreement with previous studies on tris-cyclopentadienylneodymium complexes. The zirconium metallocene Cp3Zr has been prepared, characterized crystallographically, and its reactivity studied. Its chemical behavior is controlled by presence of an electron in the non-bonding, dz2 orbital which prevents formation of base adducts Of Cp3Zr, but allows Cp3Zr to abstract atoms from other molecules. Electonic and EPR spectra of Cp*2TiX complexes, where Cp* is Me5C5 and X is a monodentate, anionic ligand such as halide, have been studied. A π-bonding spectrochemical series is developed, and trends in π-bonding ability are found similar to those in other inorganic complexes. The β-agostic interactions in Cp*2TiN(Me)Ph have been examined using variable temperature EPR spectroscopy, and the enthalpy/entropy of the interaction determined. In Cp*2TiEt, enthalpy of the β-agostic interaction is -1.9 kcal/mol. The titanocene anion, Cp*2TiLi(TMEDA) (TMEDA is N,N,N`,N`-tetramethylethylenediamine), has been

  5. La Esfinge en las Monedas de Cástulo

    Directory of Open Access Journals (Sweden)

    María Paz GARCÍA-BELLIDO

    2009-10-01

    Full Text Available RESUMEN: La esfinge alada y marchando es el tipo constante en las monedas de Cástuio. En las primeras emisiones el tocado de la esfinge es vano: Mitra, Klaft y Uraeus; para el resto de las acuñaciones, casco con dos alitas. Un estudio a través de los campos culturales con iconografías de esfinges similares, nos llevan a descartar una influencia romano-griega para estas monedas de fines del siglo III b.C. Las esfinges aparecidas en la Penínsuh son de estirpe clásica: sentadas sobre sus cuartos traseros, la de Agost, Salobral, etc. La nuestra mantiene una iconografía típicamente oriental'zante, pasada de moda en el mundo clásico hacía cuatro siglos y cuya pervivencia sólo se explica dentro del ámbito púnico, tradicional en sus representaciones pero tan influido por el estilo heleníst'co en época bárquida. Ni los tocado,, de la esfinge ni la iconografía en general pueden haber nacido bajo auspicios romanos.ABSTRACT: The winged and walking Sphinx is the constant type on the coins of Cástulo. In the first issues, the headdress can vary: mitra, klaft and uraeus. Very soon, this headdress becomes constant in all the rest of issues: a helmet with two winglets. A study through the cultural fields of the iconography of similar sphinxes, leads us to discard any roman-greek influence, in these coins of the end of the third century B.C. The sphinxes which appeared in the Peninsula are of classical lineage: seated on their rear legs, the one of Agost, Salobral, etc... Ours, maintains an iconography typically orientalizing, which had been outdated for four centuries in the classical world and whose survivorship can only be explained within a punie milieu, traditional in its representations but influenced by the helenistic style in the barquida era. Neithere the headdresses of the sphinxes nor the iconography in general can have been born under roman auspices.

  6. Structures of the dehydrogenation products of methane activation by 5d transition metal cations.

    Science.gov (United States)

    Lapoutre, V J F; Redlich, B; van der Meer, A F G; Oomens, J; Bakker, J M; Sweeney, A; Mookherjee, A; Armentrout, P B

    2013-05-23

    The activation of methane by gas-phase transition metal cations (M(+)) has been studied extensively, both experimentally and using density functional theory (DFT). Methane is exothermically dehydrogenated by several 5d metal ions to form [M,C,2H](+) and H2. However, the structure of the dehydrogenation product has not been established unambiguously. Two types of structures have been considered: a carbene structure where an intact CH2 fragment is bound to the metal (M(+)-CH2) and a carbyne (hydrido-methylidyne) structure with both a CH and a hydrogen bound to the metal separately (H-M(+)-CH). For metal ions with empty d-orbitals, an agostic interaction can occur that could influence the competition between carbene and carbyne structures. In this work, the gas phase [M,C,2H](+) (M = Ta, W, Ir, Pt) products are investigated by infrared multiple-photon dissociation (IR-MPD) spectroscopy using the Free-Electron Laser for IntraCavity Experiments (FELICE). Metal cations are formed in a laser ablation source and react with methane pulsed into a reaction channel downstream. IR-MPD spectra of the [M,C,2H](+) species are measured in the 300-3500 cm(-1) spectral range by monitoring the loss of H (2H in the case of [Ir,C,2H](+)). For each system, the experimental spectrum closely resembles the calculated spectrum of the lowest energy structure calculated using DFT: for Pt, a classic C(2v) carbene structure; for Ta and W, carbene structures that are distorted by agostic interactions; and a carbyne structure for the Ir complex. The Ir carbyne structure was not considered previously. To obtain this agreement, the calculated harmonic frequencies are scaled with a scaling factor of 0.939, which is fairly low and can be attributed to the strong redshift induced by the IR multiple-photon excitation process of these small molecules. These four-atomic species are among the smallest systems studied by IR-FEL based IR-MPD spectroscopy, and their spectra demonstrate the power of IR

  7. Organometallic polymers assembled from cation-pi interactions: use of ferrocene as a ditopic linker within the homologous series [{(Me3Si)2NM}2.(Cp2Fe)]infinity (M=Na, K, Rb, Cs; Cp=cyclopentadienyl).

    Science.gov (United States)

    Morris, J Jacob; Noll, Bruce C; Honeyman, Gordon W; O'Hara, Charles T; Kennedy, Alan R; Mulvey, Robert E; Henderson, Kenneth W

    2007-01-01

    Addition of ferrocene to solutions of alkali metal hexamethyldisilazides M(HMDS) in arenes (in which M=Na, K, Rb, Cs) allows the subsequent crystallization of the homologous series of compounds [{(Me(3)Si)(2)NM}(2) (Cp(2)Fe)](infinity) (1-4). Similar reactions using LiHMDS led to the recrystallization of the starting materials. The crystal structures of 1-4 reveal the formation of one-dimensional chains composed of dimeric [{M(HMDS)}(2)] aggregates, which are bridged through neutral ferrocene molecules by eta(5)-cation-pi interactions. In addition, compounds 3 and 4 also contain interchain agostic M--C interactions, producing two-dimensional 4(4)-nets. Whereas 1 and 2 were prepared from toluene, the syntheses of 3 and 4 required the use of tert-butylbenzene as the reaction media. The attempted crystallization of 3 and 4 from toluene resulted in formation of the mixed toluene/ferrocene solvated complexes [{(Me(3)Si)(2)NM)(2)}(2) (Cp(2)Fe)(x)(Tol)(y)](infinity) (in which M=Rb, x=0.6, y=0.8, 5; M=Cs, x=0.5, y=1, 6). The extended solid-state structures of 5 and 6 are closely related to the 4(4)-sheets 3 and 4, but are now assembled from a combination of cation-pi, agostic, and pi-pi interactions. The charge-separated complex [K{(C(6)H(6))(2)Cr}(1.5)(Mes)][Mg(HMDS)(3)] (15) was also structurally characterized and found to adopt an anionic two-dimensional 6(3)-network through doubly eta(3)-coordinated bis(benzene)chromium molecules. DFT calculations at the B3 LYP/6-31G* level of theory indicate that the binding energies of both ferrocene and toluene to the M(HMDS) dimers increases in the sequence Li

  8. Interaction of acetonitrile with platinum (111): more properties of the η 2(C,N) state and new species in the submonolayer

    Science.gov (United States)

    Ou, E. C.; Young, P. A.; Norton, P. R.

    1992-10-01

    The interaction of CH 3CN on Pt(111) was studied with infrared reflection absorption spectroscopy (IRRAS), temperature programmed desorption (TPD) and work function change (Δφ). Submonolayer, monolayer and multilayer states are distinguished. Measurements at submonolayer coverages are consistent with an orientation of adsorbed acetonitrile which is parallel to the surface. No infrared absorption attributable to the CN bond at around 2200 cm -1 or 1600 cm -1 could be detected by IRRAS, consistent with an η 2(C,N) state for the monolayer, as suggested by Sexton and Avery. In addition, IRRAS data showed that there was a red shift of the C-H stretches of the methyl group with the absence of methyl bends. Agostic bonding involving the β-hydrogen is proposed to explain this observation. We denote this state as η 2∗(C,N) to emphasize the involvement of the β-hydrogen in chemisorption. For monolayer coverage, IR activity for all bands present in the submonolayer spectrum decreased in intensity. The magnitude of this effect seems too large to be attributed solely to screening by neighbouring dipoles. The multilayer showed IR bands in good agreement with those in the vapour phase spectrum. When the crystal was annealed to remove the multilayer and part of the monolayer, IRRAS detected two species with the CN dipole having a component normal to the surface. These are the terminal and bridge bonded acetonitrile adsorbed via the nitrogen atom. Implications for chemical vapour deposition using cyanide containing precursors are discussed.

  9. Mechanisms and dynamics of protonation and lithiation of ferrocene.

    Science.gov (United States)

    Sharma, Nishant; Ajay, Jayanth K; Venkatasubbaiah, Krishnan; Lourderaj, Upakarasamy

    2015-09-14

    By elucidating the mechanism of the simplest electrophilic substitution reaction of ferrocene, it was found that the verification of the protonation reaction has been a difficulty. In the work reported here, ab initio chemical dynamics simulations were performed at B3LYP/DZVP level of theory to understand the atomic level mechanisms of protonation and lithiation of ferrocene. Protonation of ferrocene resulted in the agostic and metal-protonated forms. Trajectory calculations revealed that protonation of ferrocene occurs by exo and endo mechanisms, with exo being the major path. H(+) was found to be mobile and hopped from the Cp ring to the metal center and vice versa after the initial attack on ferrocene, with the metal-complex having a shorter lifetime. These results remove the ambiguity surrounding the mechanism, as proposed in earlier experimental and computational studies. Lithiation of ferrocene resulted in the formation of cation-π and metal-lithiated complexes. Similar to protonation, trajectory results revealed that both exo and endo paths were followed, with the exo path being the major one. In addition, lithiated-ferrocene exhibited planetary motion. The major path (exo) followed in the protonation and lithiation of ferrocene is consistent with the observations in earlier experimental studies for other hard electrophiles.

  10. Theoretical evidence for bond stretch isomerism in Grubbs olefin metathesis.

    Science.gov (United States)

    Remya, Premaja R; Suresh, Cherumuttathu H

    2017-07-15

    A comprehensive density functional theory study on the dissociative and associative mechanisms of Grubbs first and second generation olefin metathesis catalysis reveals that ruthenacyclobutane intermediate (RuCB) observed in the Chauvin mechanism is not unique as it can change to a non-metathetic ruthenacyclobutane (RuCB') via the phenomenon of bond stretch isomerism (BSI). RuCB and RuCB' differ mainly in RuCα , RuCβ , and Cα Cβ bond lengths of the metallacycle. RuCB is metathesis active due to the agostic type bonding-assisted simultaneous activation of both Cα Cβ bonds, giving hypercoordinate character to Cβ whereas an absence of such bonding interactions in RuCB' leads to typical CC single bond distances and metathesis inactivity. RuCB and RuCB' are connected by a transition state showing moderate activation barrier. The new mechanistic insights invoking BSI explains the non-preference of associative mechanism and the requirement of bulky ligands in the Grubbs catalyst design. The present study lifts the status of BSI from a concept of largely theoretical interest to a phenomenon of intense importance to describe an eminent catalytic reaction. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  11. A DFT study on the effect of hydrogen in ethylene and propylene polymerization using a Ti-based heterogeneous Ziegler–Natta catalyst

    KAUST Repository

    Bahri-Laleh, Naeimeh

    2012-11-01

    Hydrogenolysis of a series of model Ziegler-Natta (Z-N) catalysts to form Ti-H bond was studied within DFT. We focused our efforts on Ti species attached to the (110) lateral cut of MgCl 2 which exist as different centres including Ti-C 2H 5, Ti-CH 2CH(CH 3) 2, and Ti-CH(CH 3)CH 2CH 3 in ethylene and propylene polymerization. In the next step, reactivity of Ti-H bond towards ethylene and propylene (1,2- and 2,1-) insertion was investigated. Results showed that insertion of ethylene and propylene into Ti-H bond has less barrier, in comparison with their insertion in Ti-C bond, however, ethylene and propylene 2,1- insertion lead to Ti-C 2H 5 and Ti-CH(CH 3) 2 centres respectively, which were stable due to strong β-agostic interactions. Finally, by considering different possible reactions of active centre, activity depression in ethylene polymerization and activity increase in propylene polymerization were explained in detail. © 2012 Elsevier B.V.

  12. Solid-state molecular organometallic chemistry. Single-crystal to single-crystal reactivity and catalysis with light hydrocarbon substrates.

    Science.gov (United States)

    Chadwick, F Mark; McKay, Alasdair I; Martinez-Martinez, Antonio J; Rees, Nicholas H; Krämer, Tobias; Macgregor, Stuart A; Weller, Andrew S

    2017-08-01

    Single-crystal to single-crystal solid/gas reactivity and catalysis starting from the precursor sigma-alkane complex [Rh(Cy2PCH2CH2PCy2)(η2η2-NBA)][BArF4] (NBA = norbornane; ArF = 3,5-(CF3)2C6H3) is reported. By adding ethene, propene and 1-butene to this precursor in solid/gas reactions the resulting alkene complexes [Rh(Cy2PCH2CH2PCy2)(alkene) x ][BArF4] are formed. The ethene (x = 2) complex, [Rh(Cy2PCH2CH2PCy2)(ethene)2][BArF4]-Oct, has been characterized in the solid-state (single-crystal X-ray diffraction) and by solution and solid-state NMR spectroscopy. Rapid, low temperature recrystallization using solution methods results in a different crystalline modification, [Rh(Cy2PCH2CH2PCy2)(ethene)2][BArF4]-Hex, that has a hexagonal microporous structure (P6322). The propene complex (x = 1) [Rh(Cy2PCH2CH2PCy2)(propene)][BArF4] is characterized as having a π-bound alkene with a supporting γ-agostic Rh···H3C interaction at low temperature by single-crystal X-ray diffraction, variable temperature solution and solid-state NMR spectroscopy, as well as periodic density functional theory (DFT) calculations. A fluxional process occurs in both the solid-state and solution that is proposed to proceed via a tautomeric allyl-hydride. Gas/solid catalytic isomerization of d3-propene, H2C 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000

  13. Solid-state molecular organometallic chemistry. Single-crystal to single-crystal reactivity and catalysis with light hydrocarbon substrates† †Electronic supplementary information (ESI) available: Full details of experimental details, spectroscopic and other analytical data, X-ray crystallography, catalytic conditions, and computational studies. CCDC 1539832–1539836. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c7sc01491k Click here for additional data file. Click here for additional data file. Click here for additional data file.

    Science.gov (United States)

    Chadwick, F. Mark; McKay, Alasdair I.; Martinez-Martinez, Antonio J.; Rees, Nicholas H.; Krämer, Tobias

    2017-01-01

    Single-crystal to single-crystal solid/gas reactivity and catalysis starting from the precursor sigma-alkane complex [Rh(Cy2PCH2CH2PCy2)(η2η2-NBA)][BArF4] (NBA = norbornane; ArF = 3,5-(CF3)2C6H3) is reported. By adding ethene, propene and 1-butene to this precursor in solid/gas reactions the resulting alkene complexes [Rh(Cy2PCH2CH2PCy2)(alkene)x][BArF4] are formed. The ethene (x = 2) complex, [Rh(Cy2PCH2CH2PCy2)(ethene)2][BArF4]-Oct, has been characterized in the solid-state (single-crystal X-ray diffraction) and by solution and solid-state NMR spectroscopy. Rapid, low temperature recrystallization using solution methods results in a different crystalline modification, [Rh(Cy2PCH2CH2PCy2)(ethene)2][BArF4]-Hex, that has a hexagonal microporous structure (P6322). The propene complex (x = 1) [Rh(Cy2PCH2CH2PCy2)(propene)][BArF4] is characterized as having a π-bound alkene with a supporting γ-agostic Rh···H3C interaction at low temperature by single-crystal X-ray diffraction, variable temperature solution and solid-state NMR spectroscopy, as well as periodic density functional theory (DFT) calculations. A fluxional process occurs in both the solid-state and solution that is proposed to proceed via a tautomeric allyl-hydride. Gas/solid catalytic isomerization of d3-propene, H2C 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000

  14. Terminal parent phosphanide and phosphinidene complexes of zirconium(IV)

    Energy Technology Data Exchange (ETDEWEB)

    Stafford, Hannah; Rookes, Thomas M.; Wildman, Elizabeth P.; Wooles, Ashley J.; Liddle, Stephen T. [School of Chemistry, The University of Manchester (United Kingdom); Balazs, Gabor; Scheer, Manfred [Institute of Inorganic Chemistry, University of Regensburg (Germany)

    2017-06-19

    The reaction of [Zr(Tren{sup DMBS})(Cl)] [Zr1; Tren{sup DMBS}=N(CH{sub 2}CH{sub 2}NSiMe{sub 2}Bu{sup t}){sub 3}] with NaPH{sub 2} gave the terminal parent phosphanide complex [Zr(Tren{sup DMBS})(PH{sub 2})] [Zr2; Zr-P=2.690(2) Aa]. Treatment of Zr2 with one equivalent of KCH{sub 2}C{sub 6}H{sub 5} and two equivalents of benzo-15-crown-5 ether (B15C5) afforded an unprecedented example (outside of matrix isolation) of a structurally authenticated transition-metal terminal parent phosphinidene complex [Zr(Tren{sup DMBS})(PH)][K(B15C5){sub 2}] [Zr3; Zr=P=2.472(2) Aa]. DFT calculations reveal a polarized-covalent Zr=P double bond, with a Mayer bond order of 1.48, and together with IR spectroscopic data also suggest an agostic-type Zr..HP interaction [ angle {sub ZrPH}=66.7 ] which is unexpectedly similar to that found in cryogenic, spectroscopically observed phosphinidene species. Surprisingly, computational data suggest that the Zr=P linkage is similarly polarized, and thus as covalent, as essentially isostructural U=P and Th=P analogues. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  15. Control of Chain Walking by Weak Neighbouring Group Interac-tions in Unsymmetric Catalysts

    KAUST Repository

    Falivene, Laura

    2017-12-20

    A combined theoretical and experimental study shows how weak attractive interactions of a neighbouring group can strongly promote chain walking and chain transfer. This accounts for the previously observed very different micro-structures obtained in ethylene polymerization by [κ2-N,O-{(2,6-(3\\',5\\'-R2C6H3)2C6H3-N=C(H)-(3,5-X,Y2-2-O-C6H2)}]NiCH3(pyridine)], namely hyperbranched oligomers for remote substituents R = CH3 versus. high molecular weight polyethylene for R = CF3. From a full mechanistic consideration the alkyl olefin complex with the growing chain cis to the salicylaldiminato oxygen donor is identified as the key species. Alternative to ethylene chain growth by insertion in this species, decoordination of the monomer to form a cis ß-agostic complex provides an entry into branching and chain transfer pathways. This release of monomer is promoted and made competitive by a weak η2-coordination of the distal aryl rings to the metal center, operative only for the case of sufficiently electron rich aryls. This concept for controlling chain walking is underlined by catalysts with other weakly coordinating furane and thio-phene motifs, which afford highly branched oligomers with > 120 branches per 1000 carbon atoms.

  16. Phosphinodi(benzylsilane) PhP{(o-C6H4CH2)SiMe2H}2: a versatile "PSi2Hx" pincer-type ligand at ruthenium.

    Science.gov (United States)

    Montiel-Palma, Virginia; Muñoz-Hernández, Miguel A; Cuevas-Chávez, Cynthia A; Vendier, Laure; Grellier, Mary; Sabo-Etienne, Sylviane

    2013-09-03

    The synthesis of the new phosphinodi(benzylsilane) compound PhP{(o-C6H4CH2)SiMe2H}2 (1) is achieved in a one-pot reaction from the corresponding phenylbis(o-tolylphosphine). Compound 1 acts as a pincer-type ligand capable of adopting different coordination modes at Ru through different extents of Si-H bond activation as demonstrated by a combination of X-ray diffraction analysis, density functional theory calculations, and multinuclear NMR spectroscopy. Reaction of 1 with RuH2(H2)2(PCy3)2 (2) yields quantitatively [RuH2{[η(2)-(HSiMe2)-CH2-o-C6H4]2PPh}(PCy3)] (3), a complex stabilized by two rare high order ε-agostic Si-H bonds and involved in terminal hydride/η(2)-Si-H exchange processes. A small free energy of reaction (ΔrG298 = +16.9 kJ mol(-1)) was computed for dihydrogen loss from 3 with concomitant formation of the 16-electron species [RuH{[η(2)-(HSiMe2)-CH2-o-C6H4]PPh[CH2-o-C6H4SiMe2]}(PCy3)] (4). Complex 4 features an unprecedented (29)Si NMR decoalescence process. The dehydrogenation process is fully reversible under standard conditions (1 bar, 298 K).

  17. Web-based experiments for the study of collective social dynamics in cultural markets

    National Research Council Canada - National Science Library

    Salganik, Matthew J; Watts, Duncan J

    2009-01-01

    .... However, this process is hindered by the difficulty of experimentally studying how individual behavioral tendencies lead to collective social dynamics in large groups of people interacting over time...

  18. High pressure-induced changes in milk proteins and possible applications in dairy technology

    National Research Council Canada - National Science Library

    López-Fandiño, Rosina

    2006-01-01

    .... These events influence rennet coagulation properties of milk, with micellar disintegration favoring coagulation and whey protein denaturation hindering the aggregation of renneted micelles and enhancing cheese yield...

  19. OPTIMIZATION OF CELL DISRUPTION IN RAPHIDOCELIS SUBCAPITATA AND CHLORELLA VULGARIS FOR BIOMARKER EVALUATION

    National Research Council Canada - National Science Library

    Adeolu Aderemi; Colin Hunter; Ole Pahl; Xinhua Shu

    2015-01-01

      Raphidocelis subcapitata and Chlorella vulgaris are bioassay microalgae with rigid cellulosic cell wall which can hinder the release of intracellular proteins often studied as toxicity biomarkers...

  20. Biosafety Data as Confidential Business Information: e1001499

    National Research Council Canada - National Science Library

    Kaare M Nielsen

    2013-01-01

      Unfortunately, lack of stringent standards, international harmonization, and transparency, as well as remaining claims of confidentiality on biosafety-relevant data generate consumer distrust, hinder...

  1. Molecular Mechanisms of ZnO Nanoparticle Dispersion in Solution: Modeling of Surfactant Association, Electrostatic Shielding and Counter Ion Dynamics

    National Research Council Canada - National Science Library

    Duchstein, Patrick; Milek, Theodor; Zahn, Dirk

    2015-01-01

    .... While dangling poly-ethylene oxide chains provide only a limited degree of sterical hindering to nanoparticle agglomeration, the key mechanism of surface stabilization is electrostatic shielding...

  2. The High School as Workplace.

    Science.gov (United States)

    Siegel, Janice

    1999-01-01

    Studied six northern California high schools implementing various educational reforms involving alternative organizational structures, and how their facilities helped or hindered their implementation. (EV)

  3. Linking social and pathogen transmission networks using microbial genetics in giraffe (Giraffa camelopardalis)

    National Research Council Canada - National Science Library

    VanderWaal, Kimberly L; Atwill, Edward R; Isbell, Lynne. A; McCowan, Brenda; Altizer, Sonia

    2014-01-01

    Although network analysis has drawn considerable attention as a promising tool for disease ecology, empirical research has been hindered by limitations in detecting the occurrence of pathogen transmission...

  4. New insights into landslide processes around volcanic islands from Remotely Operated Vehicle (ROV) observations offshore Montserrat

    National Research Council Canada - National Science Library

    Watt, S. F. L; Jutzeler, M; Talling, P. J; Carey, S. N; Sparks, R. S. J; Tucker, M; Stinton, A. J; Fisher, J. K; Wall‐Palmer, D; Hühnerbach, V; Moreton, S. G

    2015-01-01

    Submarine landslide deposits have been mapped around many volcanic islands, but interpretations of their structure, composition, and emplacement are hindered by the challenges of investigating deposits directly...

  5. Applicability of the Compensatory Encoding Model in Foreign Language Reading: An Investigation with Chinese College English Language Learners

    National Research Council Canada - National Science Library

    Feifei Han

    2017-01-01

    ...; the Compensatory Encoding Model maintains that slow word recognition and small working memory do not normally hinder reading comprehension, as readers are able to operate metacognitive strategies...

  6. Direct-bandgap light-emitting germanium in tensilely strained nanomembranes

    National Research Council Canada - National Science Library

    Jose R. Sánchez-Pérez; Cicek Boztug; Feng Chen; Faisal F. Sudradjat; Deborah M. Paskiewicz; RB Jacobson; Max G. Lagally; Roberto Paiella

    2011-01-01

    .... This basic materials property has so far hindered the development of group-IV photonic active devices, including diode lasers, thereby significantly limiting our ability to integrate electronic...

  7. Computation provides chemical insight into the diverse hydride NMR chemical shifts of [Ru(NHC)4(L)H]0/+ species (NHC = N-heterocyclic carbene; L = vacant, H2, N2, CO, MeCN, O2, P4, SO2, H-, F- and Cl-) and their [Ru(R2PCH2CH2PR2)2(L)H]+ congeners.

    Science.gov (United States)

    Häller, L Jonas L; Mas-Marzá, Elena; Cybulski, Mateusz K; Sanguramath, Rajashekharayya A; Macgregor, Stuart A; Mahon, Mary F; Raynaud, Christophe; Russell, Christopher A; Whittlesey, Michael K

    2017-02-28

    Relativistic density functional theory calculations, both with and without the effects of spin-orbit coupling, have been employed to model hydride NMR chemical shifts for a series of [Ru(NHC)4(L)H]0/+ species (NHC = N-heterocyclic carbene; L = vacant, H2, N2, CO, MeCN, O2, P4, SO2, H-, F- and Cl-), as well as selected phosphine analogues [Ru(R2PCH2CH2PR2)2(L)H]+ (R = iPr, Cy; L = vacant, O2). Inclusion of spin-orbit coupling provides good agreement with the experimental data. For the NHC systems large variations in hydride chemical shift are shown to arise from the paramagnetic term, with high net shielding (L = vacant, Cl-, F-) being reinforced by the contribution from spin-orbit coupling. Natural chemical shift analysis highlights the major orbital contributions to the paramagnetic term and rationalizes trends via changes in the energies of the occupied Ru dπ orbitals and the unoccupied σ*Ru-H orbital. In [Ru(NHC)4(η2-O2)H]+ a δ-interaction with the O2 ligand results in a low-lying LUMO of dπ character. As a result this orbital can no longer contribute to the paramagnetic shielding, but instead provides additional deshielding via overlap with the remaining (occupied) dπ orbital under the Lz angular momentum operator. These two effects account for the unusual hydride chemical shift of +4.8 ppm observed experimentally for this species. Calculations reproduce hydride chemical shift data observed for [Ru(iPr2PCH2CH2PiPr2)2(η2-O2)H]+ (δ = -6.2 ppm) and [Ru(R2PCH2CH2PR2)2H]+ (ca. -32 ppm, R = iPr, Cy). For the latter, the presence of a weak agostic interaction trans to the hydride ligand is significant, as in its absence (R = Me) calculations predict a chemical shift of -41 ppm, similar to the [Ru(NHC)4H]+ analogues. Depending on the strength of the agostic interaction a variation of up to 18 ppm in hydride chemical shift is possible and this factor (that is not necessarily readily detected experimentally) can aid in the interpretation of hydride chemical shift

  8. Experimental electron density studies as key for understanding the chemical and physical properties in selected model systems; Experimentelle Elektronendichtestudien als Schluessel zum Verstaendnis chemischer und physikalischer Eigenschaften in ausgewaehlten Modellsystemen

    Energy Technology Data Exchange (ETDEWEB)

    Hauf, Christoph

    2014-12-17

    The topological analysis of experimentally determined electron density distributions, employing the quantum theory of atoms in molecules developed by Richard FW Bader, was used in this thesis to study chemically or physically motivated questions in appropriate model systems. First, transition metal complexes with activated C-H bonds or Si-H bonds were examined which led to a better understanding of agostic interactions. An important tool during these investigations is the so called atomic graph, which describes the characteristic spatial arrangement of the critical points of the Laplacefield of the electron density distribution in the valence shell of the relevant atoms. It reveals zones with a locally concentrated or depleted electron density distribution. This leads to the empirical rule, that a strong activation of C-H bonds or Si-H bonds is only observed when the hydrogen atom faces a pronounced charge depletion zone at the transition metal atom. In addition, the quasi one-dimensional rare-earth transition metal carbides Sc{sub 3}FeC{sub 4}, Sc{sub 3}CoC{sub 4} and Sc{sub 3}NiC{sub 4} were examined. Although all three compounds are isotypic at room temperature, it was revealed during this thesis, that only Sc{sub 3}CoC{sub 4} undergoes a structural phase transition at a temperature of ∝ 70 K and becomes superconducting below a critical temperature of 4.5 K. The main reason for this behaviour is the variation of the valence electrons through the exchange of Fe by Co or Ni. This results in the occupation of progressively higher energy electronic states and a raising of the Fermi level. The change in the nature of the electronic states at the Fermi level is in turn reflected by the different atomic graphs of the transition metal atoms and the distinct physical properties of these three compounds.

  9. Elucidating the Link between NMR Chemical Shifts and Electronic Structure in d(0) Olefin Metathesis Catalysts.

    Science.gov (United States)

    Halbert, Stéphanie; Copéret, Christophe; Raynaud, Christophe; Eisenstein, Odile

    2016-02-24

    The nucleophilic carbon of d(0) Schrock alkylidene metathesis catalysts, [M] = CHR, display surprisingly low downfield chemical shift (δ(iso)) and large chemical shift anisotropy. State-of-the-art four-component relativistic calculations of the chemical shift tensors combined with a two-component analysis in terms of localized orbitals allow a molecular-level understanding of their orientations, the magnitude of their principal components (δ11 > δ22 > δ33) and associated δ(iso). This analysis reveals the dominating influence of the paramagnetic contribution yielding a highly deshielded alkylidene carbon. The largest paramagnetic contribution, which originates from the coupling of alkylidene σ(MC) and π*(MC) orbitals under the action of the magnetic field, is analogous to that resulting from coupling σ(CC) and π*(CC) in ethylene; thus, δ11 is in the MCH plane and is perpendicular to the MC internuclear direction. The higher value of carbon-13 δ(iso) in alkylidene complexes relative to ethylene is thus due to the smaller energy gap between σ(MC) and π*(MC) vs this between σ(CC) and π*(CC) in ethylene. This effect also explains why the highest value of δ(iso) is observed for Mo and the lowest for Ta, the values for W and Re being in between. In the presence of agostic interaction, the chemical shift tensor principal components orientation (δ22 or δ33 parallel or perpendicular to π(MX)) is influenced by the MCH angle because it determines the orientation of the alkylidene CHR fragment relative to the MC internuclear axis. The orbital analysis shows how the paramagnetic terms, understood with a localized bond model, determine the chemical shift tensor and thereby δ(iso).

  10. Unprecedented Reaction Pathway of Sterically Crowded Calcium Complexes: Sequential C-N Bond Cleavage Reactions Induced by C-H Bond Activations.

    Science.gov (United States)

    Yang, Yang; Wang, Haobing; Ma, Haiyan

    2017-01-17

    Five bis(quinolylmethyl)-(1H-indolylmethyl)amine (BQIA) compounds, that is, {(quinol-8-yl-CH2 )2 NCH2 (3-Br-1H-indol-2-yl)} (L(1) H) and {[(8-R(3) -quinol-2-yl)CH2 ]2 NCH(R(2) )[3-R(1) -1H-indol-2-yl]} (L(2-5) H) (L(2) H: R(1) =Br, R(2) =H, R(3) =H; L(3) H: R(1) =Br, R(2) =H, R(3) =iPr; L(4) H: R(1) =H, R(2) =CH3 , R(3) =iPr; L(5) H: R(1) =H, R(2) =nBu, R(3) =iPr) were synthesized and used to prepare calcium complexes. The reactions of L(1-5) H with silylamido calcium precursors (Ca[N(SiMe2 R)2 ]2 (THF)2 , R=Me or H) at room temperature gave heteroleptic products (L(1, 2) )CaN(SiMe3 )2 (1, 2), (L(3, 4) )CaN(SiHMe2 )2 (3 a, 4 a) and homoleptic complexes (L(3, 5) )2 Ca (D3, D5). NMR and X-ray analyses proved that these calcium complexes were stabilized through Ca⋅⋅⋅C-Si, Ca⋅⋅⋅H-Si or Ca⋅⋅⋅H-C agostic interactions. Unexpectedly, calcium complexes ((L(3-5) )CaN(SiMe3 )2 ) bearing more sterically encumbered ligands of the same type were extremely unstable and underwent C-N bond cleavage processes as a consequence of intramolecular C-H bond activation, leading to the exclusive formation of (E)-1,2-bis(8-isopropylquinol-2-yl)ethane. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Synthesis and structural characterization of scandium SALEN complexes.

    Science.gov (United States)

    Meermann, Christian; Sirsch, Peter; Törnroos, Karl W; Anwander, Reiner

    2006-02-28

    A series of heteroleptic scandium SALEN complexes, [(SALEN)Sc(mu-Cl)]2 and (SALEN)Sc[N(SiHMe2)2] is obtained via amine elimination reactions using [Sc(N(i)Pr2)2(mu-Cl)(THF)]2 and Sc[N(SiHMe2)2]3(THF) as metal precursors, respectively. H(2)SALEN ligand precursors comprising H2Salen [(1,2-ethandiyl)bis(nitrilomethylidyne)bis(2,4-di-tert-butyl)phenol], H2Salpren [(2,2-dimethylpropanediyl)bis(nitrilomethylidyne)bis(2,4-di-tert-butyl)phenol], H2Salcyc [(1R,2R)-(-)-1,2-cyclohexanediyl)bis(nitrilomethylidyne)bis(2,4-di-tert-butyl)phenol] and H2Salphen [((1S,2S)-(-)-1,2-diphenylethandiyl)bis(nitrilomethylidyne)bis(2,4-di-tert-butyl)phenol] are selected according to solubility and ligand backbone variation ("=N-(R)-N=" bite angle) criteria. Consideration is given to the feasibility of [Cl --> NR2] and [N(SiHMe2)2--> OSiR3] secondary ligand exchange reactions. X-ray crystal structure analyses of donor-free (Salpren)Sc(N(i)Pr2), (R,R)-(Salcyc)Sc[N(SiHMe2)2], (Salen)Sc(OSi(t)BuPh2) and (Salphen)Sc(OSiH(t)Bu2) reveal (i) a very short Sc-N bond distance of 2.000(3) A, (ii) weak beta(Si-H)(amido)-Sc agostic interactions and (iii) an exclusive intramolecularly tetradentate and intrinsically bent coordination mode of the SALEN ligands with angle(Ph,Ph) dihedral angles and Sc-[N(2)O(2)] distances in the 124.27(9)-127.7(3) degrees and 0.638(1)-0.688(1) A range, respectively.

  12. Cationic rare-earth metal SALEN complexes.

    Science.gov (United States)

    Liu, Qiancai; Meermann, Christian; Görlitzer, Hans W; Runte, Oliver; Herdtweck, Eberhardt; Sirsch, Peter; Törnroos, Karl W; Anwander, Reiner

    2008-11-28

    Complexes (Salpren(tBu,tBu))Y[N(SiHMe2)2](thf) and (SALEN(tBu,tBu))La[N(SiHMe2)2](thf) (SALEN(tBu,tBu) = Salcyc(tBu,tBu) and Salpren(tBu,tBu)) were prepared from Ln[N(SiHMe2)2]3(thf)2 and H2SALEN(tBu,tBu). The yttrium complex was characterized by X-ray crystallography revealing intrinsic solid-state structural features: the metal centre is displaced by 1.05 angstroms from the [N2O2] least squares plane of a highly bent Salpren(tBu,tBu) ligand (angle(Ph,Ph) dihedral angle of 80.4(1) degrees ) and is coordinated asymmetrically by the silylamide ligand exhibiting one significant Y---(HSi) beta-agostic interaction (Y-N1-Si1, 106.90(9) degrees; Y---Si1, 3.2317(6) angstroms). Complexes (SALEN(tBu,tBu))Ln[N(SiHMe2)2](thf)n (n = 1, Sc; n = 2, Y, La) react with ammonium tetraphenylborate to form the ion pairs [(SALEN(tBu,tBu))Ln(thf)n][BPh4]. The cationisation was proven by X-ray crystal structure analyses of [(Salpren(tBu,tBu))Sc(thf)2][B(C6H5)4].2(thf) and [(Salpren(tBu,tBu))Ln(thf)3][B(C6H5)4].4(thf) (Ln = Y, La), showing an octahedral and pentagonal-bipyramidal coordination geometry, respectively.

  13. Seen but not heard: School-based professionals’ oversight of autism in children from ethnic minority groups

    NARCIS (Netherlands)

    Burke, D.A.; Koot, H.M.; Begeer, S.M.

    2015-01-01

    Previous studies have shown that ethnic background hinders clinician detection of autistic features in children from non-western minority groups. The use of a structured instrument during evaluation of these children can reduce the risk of hindered detection. The aims of the current studies were to

  14. 77 FR 1877 - Medicare Program; Medicare Advantage and Prescription Drug Benefit Programs: Negotiated Pricing...

    Science.gov (United States)

    2012-01-12

    ... hinder the design of, the offering of, or enrollment in an RDS plan. II. Provisions of the Rules and... to report drug costs on a pass-through or lock-in basis, and could choose to report rebates and other..., would hinder the offering of, design of, or enrollment in, RDS plans. 1. Legal Theory 1: Interpretation...

  15. Constructing a bit string universe. Progress report

    Energy Technology Data Exchange (ETDEWEB)

    Noyes, H.P.; Manthey, M.J.; Gefwert, C.

    1984-02-01

    We present a case for discrete, constructive physics that generates four scale constants, a connection to laboratory events and scattering theory that ties these to the dimensional constants c, h, m/sub p/, and G, and a tentative quantum number assignment consistent with standard model for leptons and quarks with three generations. Current first approximations from the theory are dirac constant c/e/sup 2/ = 137 +- O(1/137), dirac constant c/Gm/sup 2//sub p/ - 2/sup 127/ + 136 approx. = 1.7 x 10/sup 38/(1 +- 0(1/137)), and m/sub p//m/sub e/ = 1836.151497... +-. Our understanding of wave-particle dualism and observational cosmology creates no more experimental paradoxes than currently accepted views - perhaps fewer. 19 references.

  16. Efficient EMD-based Similarity Search in Multimedia Databases via Flexible Dimensionality Reduction

    DEFF Research Database (Denmark)

    Wichterich, Marc; Assent, Ira; Philipp, Kranen

    2008-01-01

    to medium dimensionality. However, multimedia applications commonly exhibit high-dimensional feature representations for which the computational complexity of the EMD hinders its adoption. An efficient query processing approach that mitigates and overcomes this effect is crucial. We propose novel...

  17. Iran's Economic Conditions: U.S. Policy Issues

    National Research Council Canada - National Science Library

    Ilias, Shayerah

    2009-01-01

    .... Since 2000, Iran has enjoyed broad-based economic growth. However, strong economic performance has been hindered by high levels of inflation and unemployment and low levels of foreign investment...

  18. Development and evaluation of an in vitro vaginal model for assessment of drug's biopharmaceutical properties: curcumin

    National Research Council Canada - National Science Library

    Berginc, Katja; Skalko-Basnet, Nataša; Basnet, Purusotam; Kristl, Albin

    2012-01-01

    Vaginal administration is a promising alternative to the per-oral route in achieving systemic or local therapeutic effects, when intestinal drug absorption is hindered by problematic biopharmaceutical drug properties...

  19. Fiber optic monitoring methods for composite steel-concrete structures based on determination of neutral axis and deformed shape.

    Science.gov (United States)

    2014-01-01

    Structural Health Monitoring has great potential to provide valuable information about the actual structural condition and can help optimize the management activities. However, few effective and robust monitoring methods exist which hinders a nationw...

  20. On-Board Pressurization Systems for Sample Return Missions Project

    Data.gov (United States)

    National Aeronautics and Space Administration — To-date, the realization of high-performance liquid bipropellant rocket engines for ascent vehicle and sample return applications has largely been hindered by the...

  1. Microspectroscopic Confocal Raman and Macroscopic Biophysical Measurements in the in vivo Assessment of the Skin Barrier: Perspective for Dermatology and Cosmetic Sciences

    NARCIS (Netherlands)

    Falcone, D.; Uzunbajakava, N.E.; Varghese, B.; Aquino Santos, G.R. de; Richters, R.J.H.; Kerkhof, P.C.M. van de; Erp, P.E.J. van

    2015-01-01

    Skin barrier function, confined to the stratum corneum, is traditionally evaluated using established, noninvasive biophysical methods like transepidermal water loss, capacitance and conductance. However, these methods neither measure skin molecular composition nor its structure, hindering the actual

  2. A Novel Pressure Indicator for Continuous Flow PCR Chip Using Micro Molded PDMS Pillar Arrays

    National Research Council Canada - National Science Library

    Zhao, Yi; Zhang, Xin

    2005-01-01

    .... Continuous flow PCR chip releases biologists from their laborious exercises. The use of such chip is, however, hindered by costly expense of the syringe pump, which is used to maintain a constant flow rate...

  3. A BIOPSY PROCEDURE FOR DETERMINING FILET AND PREDICTING WHOLE-FISH MERCURY CONCENTRATION

    Science.gov (United States)

    Although mercury contamination of fish is a widespread phenomenon, its regional evaluation is hindered by the reluctance of permitting agencies to grant collection permits, securing adequate freezer space, and processing whole, large fish or filets. We evaluated Hg concentration...

  4. CONCEPTUALIZATION OF MENTAL ILLNESS WITHIN ARAB CULTURES: MEETING CHALLENGES IN CROSS-CULTURAL SETTINGS

    National Research Council Canada - National Science Library

    Sayed, Mohamed A

    2003-01-01

    .... The paper also attempts to delineate some of the cultural barriers that may be significant in explaining a set of mechanisms that facilitate or hinder the seeking of psychological help by Arab...

  5. Author Details

    African Journals Online (AJOL)

    Insight into the Utilization of Cloud and Mobile Computing in a service oriented world. Abstract PDF · Vol ... Technical Challenges Hindering Development of Robust Wireless Network Platforms to Support Emerging Applications. Abstract PDF.

  6. GENDER INEQUALITY IN THE LABOR MARKET: THE PRINCIPLE OF EQUALITY FOR THE REALIZATION OF THE PRINCIPLE OF NON- DISCRIMINATION AGAINST WOMEN

    National Research Council Canada - National Science Library

    L. R. Rita Lima; S. F. S. Félix Moraes; T. M. S. Maria Nodari

    2016-01-01

    .... The discrimination and the culture of factors hinder the participation of women in equal or higher level of men in the labor market, however women have higher levels of study than men, which proves...

  7. Stepping out of history : Mindfulness improves insight problem solving

    NARCIS (Netherlands)

    Ostafin, B.D.; Kassman, K.T.

    Insight problem solving is hindered by automated verbal-conceptual processes. Because mindfulness meditation training aims at "nonconceptual awareness" which involves a reduced influence of habitual verbal-conceptual processes on the interpretation of ongoing experience, mindfulness may facilitate

  8. Concentration and Quantification of Somatic and F+ Coliphage from Recreational Waters

    Science.gov (United States)

    Somatic and F+ coliphages are promising alternative fecal indicators, but current detection methods are hindered by lower levels of coliphages in surface waters compared to traditional bacterial fecal indicators. We evaluated the ability of dead-end hollow fiber ultrafiltration (...

  9. A re-evaluation of the size of the white shark (Carcharodon carcharias) population off California, USA

    National Research Council Canada - National Science Library

    Burgess, George H; Bruce, Barry D; Cailliet, Gregor M; Goldman, Kenneth J; Grubbs, R Dean; Lowe, Christopher G; MacNeil, M Aaron; Mollet, Henry F; Weng, Kevin C; O'Sullivan, John B

    2014-01-01

    White sharks are highly migratory and segregate by sex, age and size. Unlike marine mammals, they neither surface to breathe nor frequent haul-out sites, hindering generation of abundance data required to estimate population size...

  10. Factors influencing work participation of adults with developmental dyslexia : a systematic review

    NARCIS (Netherlands)

    de Beer, Joost; Engels, Josephine; Heerkens, Yvonne; van der Klink, Jac

    2014-01-01

    Background: Evidence has been synthesized to determine hindering and facilitating factors associated with the work participation of adults with developmental dyslexia (DD), classified according to the International Classification of Functioning, Disability and Health (ICF). Methods: A systematic

  11. Description and Initial Evaluation of a Text Message Based Reporting Method for Marine Recreational Anglers

    National Research Council Canada - National Science Library

    M. Scott Baker Jr; Ian Oeschger

    2009-01-01

    ... and to increase angler participation and confidence in the fisheries management process. Limitations to self-reported data aside, the lack of a portable, electronic reporting device for the average angler has hindered development of new survey methods...

  12. "The Lord's Will Be Done": A Study of Organization in the U.S. Army Chaplaincy During the Civil War

    National Research Council Canada - National Science Library

    Weddle, Donna

    1999-01-01

    This paper examines the background, organization, and duties of U.S. Army chaplains during the Civil War to determine factors which helped or hindered their efforts to provide religious support to soldiers...

  13. Molecular phylogenetics and character evolution of morphologically diverse groups, Dendrobium section Dendrobium and allies

    National Research Council Canada - National Science Library

    Takamiya, Tomoko; Wongsawad, Pheravut; Sathapattayanon, Apirada; Tajima, Natsuko; Suzuki, Shunichiro; Kitamura, Saki; Shioda, Nao; Handa, Takashi; Kitanaka, Susumu; Iijima, Hiroshi; Yukawa, Tomohisa

    2014-01-01

    .... The genus Dendrobium, one of the largest genera in the Orchidaceae, includes ∼1100 species, and enormous morphological diversification has hindered the establishment of consistent classification systems covering all major groups of this genus...

  14. Magnetic levitation of single cells

    National Research Council Canada - National Science Library

    Naside Gozde Durmus; H. Cumhur Tekin; Sinan Guven; Kaushik Sridhar; Ahu Arslan Yildiz; Gizem Calibasi; Ionita Ghiran; Ronald W. Davis; Lars M. Steinmetz; Utkan Demirci

    2015-01-01

    .... Although magnetic levitation has previously been used for macroscale objects, its use in life sciences has been hindered by the inability to levitate microscale objects and by the toxicity of metal...

  15. How do Experts Assess Usability Problems? An Empirical Analysis of cognitive Shortcuts

    NARCIS (Netherlands)

    Lentz, Leo; de Jong, Menno D.T.

    2009-01-01

    Discusses the cognitive shortcuts that may hinder technical communicators in empathizing with readers. Explores the issue of judging the severity of problems detected in a document evaluation. Demonstrates how cognitive shortcuts may affect technical communicators' capability to assess the

  16. Humans copy rapidly increasing choices in a multiarmed bandit problem

    NARCIS (Netherlands)

    Toelch, U.; Bruce, M.J.; Meeus, M.T.H.; Reader, S.M.

    2010-01-01

    Conformist social learning, the tendency to acquire the most common trait in a group, allows individuals to rapidly acquire established beneficial traits from a multitude of options. However, conformist strategies hinder acquisition of novel advantageous behavior patterns, because such innovations

  17. NATIONAL CONFERENCE ON TOOLS FOR URBAN WATER RESOURCE MANAGEMENT AND PROTECTION: PROCEEDINGS, CHICAGO, IL, FEBRUARY 7-10, 2000

    Science.gov (United States)

    A wide array of effective water quality management and protection tools have been developed for urban environments, but implementation is hindered by a shortage of technology transfer opportunities. This National Conference on Tools for Urban Water Resource Management and Protec...

  18. Industrial upgrade and economic governance in the Pearl River Delta—a case study of Dongguan city

    National Research Council Canada - National Science Library

    Wang, Zhifeng; Xu, Xiaoming; Liang, Zhiqing

    2016-01-01

    The Pearl River Delta, one of the main regions of China’s export-oriented economy, has benefited from its traditional economic structure for three decades which in turn appeared to hinder further economic development recently...

  19. Multi-sensor sheets based on large-area electronics for advanced structural health monitoring of civil infrastructure.

    Science.gov (United States)

    2014-09-01

    Structural Health Monitoring has a great potential to provide valuable information about the actual structural : condition and can help optimize the management activities. However, few eective and robust monitoring technology exist which hinders a...

  20. Operationalization of biopsychosocial case complexity in general health care : the INTERMED project

    NARCIS (Netherlands)

    de Jonge, P; Huyse, FJ; Slaets, JPJ; Sollner, W; Stiefel, FC

    Objective: Lack of operationalization of the biopsychosocial model hinders its effective application to the increasingly prevalent problems of comorbidities in clinical presentations. Here, we describe the INTERMED, an instrument to assess biopsychosocial case complexity in general health care, and

  1. Male-biased sex ratios in laboratory rearings of gypsy moth parasitoids

    Science.gov (United States)

    Roger W. Fuester; Kenneth S. Swan; Philip B. Taylor; Keith R. Hopper; Paul Ode

    2003-01-01

    Male-biased sex ratios in laboratory colonies of parasitic wasps used in biological control are harmful because they can prevent the establishment of introduced species or hinder commercial production of species used for augmentative control.

  2. Developmental Links Between Disobedient Behavior and Social Classroom Relationships in Boys With Psychiatric Disorders in Special Education

    NARCIS (Netherlands)

    Breeman, L.D.; van Lier, P.A.C.; Wubbels, T.; Verhulst, F.C.; van der Ende, J.; Maras, A.; Hopman, J.A.B.; Tick, N.T.

    2015-01-01

    In mainstream education, positive relationships with teachers and peers have been found to positively influence children’s behavioral development. However, high levels of classroom behavior problems may hinder the formation of such positive relationships. Therefore, findings from mainstream

  3. A highly efficient polysulfide mediator for lithium-sulfur batteries

    National Research Council Canada - National Science Library

    Liang, Xiao; Hart, Connor; Pang, Quan; Garsuch, Arnd; Weiss, Thomas; Nazar, Linda F

    2015-01-01

    The lithium-sulfur battery is receiving intense interest because its theoretical energy density exceeds that of lithium-ion batteries at much lower cost, but practical applications are still hindered...

  4. Intratumor Heterogeneity and Branched Evolution Revealed by Multiregion Sequencing

    DEFF Research Database (Denmark)

    Gerlinger, Marco; Rowan, Andrew J.; Horswell, Stuart

    2012-01-01

    BACKGROUND: Intratumor heterogeneity may foster tumor evolution and adaptation and hinder personalized-medicine strategies that depend on results from single tumor-biopsy samples.METHODSTo examine intratumor heterogeneity, we performed exome sequencing, chromosome aberration analysis, and ploidy ...

  5. Perspectives of hospitalized patients with mental disorders and their clinicians on vocational goals, barriers, and steps to overcome barriers

    NARCIS (Netherlands)

    Knaeps, J.; Neyens, I.; van Weeghel, Jaap; Van Audenhove, C.

    2015-01-01

    Background: People with mental disorders experience difficulties with finding competitive jobs. In countries with longer psychiatric hospitalization periods, the vocational rehabilitation process can start during hospitalization. Yet, rehabilitation can be hindered by a lack of focus by clinicians

  6. Power dynamics among PWDs during adult learning processes ...

    African Journals Online (AJOL)

    owner

    esteem and self-confidence. (WHO, 2010a). ... impairment is an excuse for oppressive practices and society's rewards for conformity hinder PWDs' struggle against ..... Hornby, A. S. (Ed.) (2010) Oxford advanced learner's dictionary of current English.

  7. Temperature, salinity, nutrient, and primary production collected by bottle and CTD in the North Atlantic Ocean from 8/25/1903 - 11/14/1997 (NODC Accession 0000101)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile, algal species, and other data were collected using water bottle or CTD casts in the North Atlantic Ocean from WEST-HINDER and other platforms....

  8. Comparison of Phytoscreening and Direct-Push- Based Site Investigation at a Rural Megasite Contaminated with Chlorinated Ethenes

    DEFF Research Database (Denmark)

    Rein, Arno; Holm, Olaf; Trapp, Stefan

    2015-01-01

    The reliable characterization of subsurface contamination of spatially extended contaminated sites is a challenging task, especially with an unknown history of land use. Conventional technologies often fail due to temporal and financial constraints and thus hinder the redevelopment of abandoned...

  9. Counselor Treatment of Coexisting Domestic Violence and Substance Abuse: A Qualitative Study.

    Science.gov (United States)

    Chartas, Nicole D.; Culbreth, John R.

    2001-01-01

    This study explored the philosophical issues hindering the linkage of substance abuse and domestic violence treatment. Results suggest that counselors tend to use treatment models that could not concurrently assign responsibility and address either present or past victimization. (Author)

  10. Does leaf chemistry differentially affect breakdown in tropical versus temperate streams? Importance of standardized analytical techniques to measure leaf chemistry

    Science.gov (United States)

    Marcelo Ardon; Catherine M. Pringle; Susan L. Eggert

    2009-01-01

    Comparisons of the effects of leaf litter chemistry on leaf breakdown rates in tropical vs temperate streams are hindered by incompatibility among studies and across sites of analytical methods used to...

  11. The importance of social identities in the management of and recovery from ‘Diabulimia’: A qualitative exploration

    National Research Council Canada - National Science Library

    Hastings, Amy; McNamara, Niamh; Allan, Jacqueline; Marriott, Mike

    2016-01-01

    ... (and the associated identities) both contribute to and hinder recovery in this cohort. Method: Transcripts from five online focus groups with 13 members of an online support group for individuals with ‘Diabulimia...

  12. Public and Private Investment and Economic Growth in Namibia ...

    African Journals Online (AJOL)

    lasting effects. Public capital .... increase in private investment matched by a cut in public investment will assist or hinder the rate of growth of output. ..... Public Infrastructure: Evidence from State High Ways, International Tax and Public Finance,.

  13. Can massive stars be formed by accretion?

    Science.gov (United States)

    Yorke, H. W.

    2000-01-01

    Radiative effects strongly hinder the formation of massive stars. A necessary condition for accretion growth of a hydrostatic object up to high masses is the formation of and accretion through a circumstellar disk.

  14. Holistic Nursing of Forensic Patients: A Focus on Spiritual Care

    National Research Council Canada - National Science Library

    Annamaria Bagnasco; Giuseppe Aleo; Barbara Delogu; Gianluca Catania; Loredana Sasso

    2016-01-01

    .... This discussion paper focuses on understanding how nurses deliver spiritual care in Italian prisons where there are often limited resources and where organizational priorities hinder the provision of holistic nursing...

  15. "Peace to Learn"-- A Discourse Analysis of Pupils' Perceptions

    Science.gov (United States)

    Paaso, E.; Uusiautti, S.; Maatta, K.

    2013-01-01

    Peace to learn refers to a peaceful state that makes meaningful and productive learning possible--in other words, the conditions that allow or hinder pupils to work peacefully in the classroom. How pupils perceive their

  16. Design and Implementation of the International Genetics and Translational Research in Transplantation Network

    NARCIS (Netherlands)

    Asselbergs, Folkert; van Setten, Jessica; de Jonge, Nicolaas; Otten, HG; de Weger, RA; van de Graaf, Ed. A.; Kluin, Jolanda; de Bakker, Paul I W

    2015-01-01

    BACKGROUND: Genetic association studies of transplantation outcomes have been hampered by small samples and highly complex multifactorial phenotypes, hindering investigations of the genetic architecture of a range of comorbidities which significantly impact graft and recipient life expectancy. We

  17. Using Enterprise Ontology as a basis for Requirements for Cross-Organizationally Usable Applications

    NARCIS (Netherlands)

    Krouwel, M.; Op 't Land, M.

    2012-01-01

    Developing cross-organizationally usable applications is becoming increasingly important. However, actually re-using business applications has been hindered in practice often by implicit assumptions about organizational and IT implementation. We propose a method to gather requirements for cross-

  18. Prevalence of asthenopia in children: a systematic review with meta‐analysis

    Directory of Open Access Journals (Sweden)

    Manuel A.P. Vilela

    2015-07-01

    Conclusion: Although asthenopia is a frequent and relevant clinical problem in childhood, with potential consequences for learning, the scarcity of studies about the prevalence and clinical impact of asthenopia hinders the effective planning of public health measures.

  19. Project Evaluation: A Mixed-Method Study into Dilemmas in Continuation Decisions

    NARCIS (Netherlands)

    Arviansyah, A.; ter Halle, Yvette; Spil, Antonius A.M.; van Hillegersberg, Jos

    2015-01-01

    Project evaluations are highly crucial for organizations to manage their information systems and technology project portfolios. This study postulates equivocal situations as the source of dilemmas hindering stakeholders to achieve proper evaluation and purposeful decisions. We examine three factors

  20. The Exclusive Group - Expatriates Working against Corporate Goals

    DEFF Research Database (Denmark)

    Lauring, Jakob

    2004-01-01

    as destructive towards overall corporate aims to internationalise and develop managerial and organisational competencies. Specifically excluding behaviour and cultural boundary creation of the expatriate group hindered the necessary cross-cultural communication and thereby working against corporate strategy...

  1. Proposal for a Candidate Core Set of Fitness and Strength Tests for Patients with Childhood or Adult Idiopathic Inflammatory Myopathies

    NARCIS (Netherlands)

    van der Stap, Djamilla K D; Rider, Lisa G; Alexanderson, Helene; Huber, Adam M; Gualano, Bruno; Gordon, Patrick; van der Net, Janjaap; Mathiesen, Pernille; Johnson, Liam G; Ernste, Floranne C; Feldman, Brian M; Houghton, Kristin M; Singh-Grewal, Davinder; Kutzbach, Abraham Garcia; Munters, Li Alemo; Takken, Tim

    OBJECTIVE: Currently there are no evidence-based recommendations regarding fitness and strength tests for patients with childhood or adult idiopathic inflammatory myopathies (IIM). This hinders clinicians and researchers in choosing the appropriate fitness- or muscle strength-related outcome

  2. Libraries: Key to National Development | Alemna | Ghana Library ...

    African Journals Online (AJOL)

    . These include the provision of educational, political, social, economic and health information. The barriers hindering these provisions such as illiteracy, lack of trained personnel, resources, poor distribution of libraries and financial constraints ...

  3. How well do ecosystem indicators communicate the effects of anthropogenic eutrophication?

    NARCIS (Netherlands)

    McQuatters-Gollop, A.; Gilbert, A.J.; Mee, L.; Vermaat, J.E.; Artioli, Y.; Humborg, C.; Wulff, F.

    2009-01-01

    Anthropogenic eutrophication affects the Mediterranean, Black, North and Baltic Seas to various extents. Responses to nutrient loading and methods of monitoring relevant indicators vary regionally, hindering interpretation of ecosystem state changes and preventing a straightforward pan-European

  4. 27 CFR 19.456 - Adding denaturants.

    Science.gov (United States)

    2010-04-01

    ... Denaturation § 19.456 Adding denaturants. Denaturants and spirits shall be mixed in packages, tanks, or bulk... methods of mixing denaturants and spirits if he deems such denaturation will not hinder effective...

  5. Income Increase and Moving to a Better Neighbourhood : Income Increase and Moving to a Better Neighbourhood

    NARCIS (Netherlands)

    Vaalavuo, M.; van Ham, M.; Kauppinen, T.M.

    2017-01-01

    Concentration to disadvantaged neighbourhoods may hinder immigrants’ opportunities for social integration, so equal chances of translating available economic resources into mobility to less disadvantaged neighbourhoods are important. This paper adds to existing research on exits from poor

  6. Deutero-learning in organizations: A review and a reformulation

    NARCIS (Netherlands)

    Visser, M.

    2007-01-01

    Higher-order learning in and by organizations is often conceptualized in the literature as deutero-learning. However, current definitions and descriptions of this concept suffer from conceptual confusion and terminological ambiguity, impeding a proper theoretical understanding and hindering

  7. Implications of system usability on intermodal facility design.

    Science.gov (United States)

    2010-08-01

    Ensuring good design of intermodal transportation facilities is critical for effective and : satisfactory operation. Passenger use of the facilities is often hindered by inadequate space, a poor : layout, or lack of signage. This project aims to impr...

  8. Acute Effects of Stretching on Flexibility, Power and Sport Specific Performance in Fencers

    National Research Council Canada - National Science Library

    Tsolakis, Charilaos; Douvis, Andreas; Tsigganos, George; Zacharogiannis, Elias; Smirniotou, Athanasia

    2010-01-01

    Elite athletes are eager to perform to the best of their ability, regardless of different warm-up stretching techniques used before training or competition which actually help or hinder specific performance variables...

  9. Small, Light-Weight Pump Technology for On-Board Pressurization of Propellants in a Mars Ascent Vehicle Project

    Data.gov (United States)

    National Aeronautics and Space Administration — To-date, the realization of high-performance liquid bipropellant rocket engines in the micro-scale has largely been hindered by the inability to obtain "on-board"...

  10. Proximate and Mineral Composition of the Pulp of Chrysophyllum ...

    African Journals Online (AJOL)

    MBI

    2014-11-13

    , calcium .... bioavailability by hindering their hydrolytic ... of the pulp of Chrysophyllum albidum (mg/100g). ELEMENTS. PULP (mg/100g). Potassium. 256.57+5.77. Sodium. 40.00+0.00. Phosphorus. 2.21+0.03. Calcium.

  11. Space-charge effects in ultrahigh current electron bunches generated by laser-plasma accelerators

    National Research Council Canada - National Science Library

    Grüner, F. J; Schroeder, C. B; Maier, A. R; Becker, S; Mikhailova, J. M

    2009-01-01

    ...) generated in laser-plasma accelerators. At low electron energies such peak currents are expected to cause space-charge effects such as bunch expansion and induced energy variations along the bunch, potentially hindering the FEL process...

  12. Price promotions and marketing within points of sale around high schools in Greece during the 2012 economic crisis

    Directory of Open Access Journals (Sweden)

    Charis Girvalaki

    2015-12-01

    Price promotions were noted within the majority of POS close to schools. Aggressive promotional activities may hinder efforts to de-normalize tobacco use, especially during financial crisis when price promotions may pose as more attractive to potential consumers.

  13. Design and Implementation of the International Genetics and Translational Research in Transplantation Network

    NARCIS (Netherlands)

    Keating, Brendan J.; van Setten, Jessica; Jacobson, Pamala A.; Holmes, Michael V.; Verma, Shefali S.; Chandrupatla, Hareesh R.; Nair, Nikhil; Gao, Hui; Li, Yun R.; Chang, Bao-Li; Wong, Chanel; Phillips, Randy; Cole, Brian S.; Mukhtar, Eyas; Zhang, Weijia; Cao, Hongzhi; Mohebnasab, Maede; Hou, Cuiping; Lee, Takesha; Steel, Laura; Shaked, Oren; Garifallou, James; Miller, Michael B.; Karczewski, Konrad J.; Akdere, Abdullah; Gonzalez, Ana; Lloyd, Kelsey M.; McGinn, Daniel; Michaud, Zach; Colasacco, Abigail; Lek, Monkol; Fu, Yao; Pawashe, Mayur; Guettouche, Toumy; Himes, Aubree; Perez, Leat; Guan, Weihua; Wu, Baolin; Schladt, David; Menon, Madhav; Zhang, Zhongyang; Tragante, Vinicius; de Jonge, Nicolaas; Otten, Henny G.; de Weger, Roel A.; van de Graaf, Ed A.; Baan, Carla C.; Manintveld, Olivier C.; De Vlaminck, Iwijn; Piening, Brian D.; Strehl, Calvin; Shaw, Mary; Snieder, Harold; Klintmalm, Goran B.; O'Leary, Jacqueline G.; Amaral, Sandra; Goldfarb, Samuel; Rand, Elizabeth; Rossano, Joseph W.; Kohli, Utkarsh; Heeger, Peter; Stahl, Eli; Christie, Jason D.; Fuentes, Maria Hernandez; Levine, John E.; Aplenc, Richard; Schadt, Eric E.; Stranger, Barbara E.; Kluin, Jolanda; Potena, Luciano; Zuckermann, Andreas; Khush, Kiran; Alzahrani, Alhusain J.; Al-Muhanna, Fahad A.; Al-Ali, Amein K.; Al-Ali, Rudaynah; Al-Rubaish, Abdullah M.; Al-Mueilo, Samir; Byrne, Edna M.; Miller, David; Alexander, Stephen I.; Onengut-Gumuscu, Suna; Rich, Stephen S.; Suthanthiran, Manikkam; Tedesco, Helio; Saw, Chee L.; Ragoussis, Jiannis; Kfoury, Abdallah G.; Horne, Benjamin; Carlquist, John; Gerstein, Mark B.; Reindl-Schwaighofer, Roman; Oberbauer, Rainer; Wijmenga, Cisca; Palmer, Scott; Pereira, Alexandre C.; Segovia, Javier; Alonso-Pulpon, Luis A.; Comez-Bueno, Manuel; Vilches, Carlos; Jaramillo, Natalia; de Borst, Martin H.; Naesens, Maarten; Hao, Ke; MacArthur, DanielG.; Balasubramanian, Suganthi; Conlon, Peter J.; Lord, Graham M.; Ritchie, Marylyn D.; Snyder, Michael; Olthoff, Kim M.; Moore, Jason H.; Petersdorf, Effie W.; Kamoun, Malek; Wang, Jun; Monos, Dimitri S.; de Bakker, Paul I. W.; Hakonarson, Hakon; Murphy, Barbara; Lankree, Matthew B.; Garcia-Pavia, Pablo; Oetting, William S.; Birdwell, Kelly A.; Bakker, Stephan J. L.; Israni, Ajay K.; Shaked, Abraham; Asselbergs, Folkert W.

    2015-01-01

    Background. Genetic association studies of transplantation outcomes have been hampered by small samples and highly complex multifactorial phenotypes, hindering investigations of the genetic architecture of a range of comorbidities which significantly impact graft and recipient life expectancy. We

  14. Structural Conditions for Collaboration and Learning in Innovation Networks: Using an Innovation System Performance Lens to Analyse Agricultural Knowledge Systems

    NARCIS (Netherlands)

    Hermans, F.; Klerkx, L.W.A.; Roep, D.

    2015-01-01

    Purpose: We investigate how the structural conditions of eight different European agricultural innovation systems can facilitate or hinder collaboration and social learning in multidisciplinary innovation networks. Methodology: We have adapted the Innovation System Failure Matrix to investigate the

  15. Data-driven subtypes of major depressive disorder : a systematic review

    NARCIS (Netherlands)

    van Loo, Hanna M.; de Jonge, Peter; Romeijn, Jan-Willem; Kessler, Ronald C.; Schoevers, Robert A.

    2012-01-01

    Background: According to current classification systems, patients with major depressive disorder (MDD) may have very different combinations of symptoms. This symptomatic diversity hinders the progress of research into the causal mechanisms and treatment allocation. Theoretically founded subtypes of

  16. Windturbines: invloed op de beleving en gezondheid van omwonenden : GGD Informatieblad medische milieukunde Update 2013

    NARCIS (Netherlands)

    van Kamp I; Dusseldorp A; van den Berg GP; Hagens WI; Slob MJA; MNS; M&V

    2014-01-01

    Mensen die dichtbij windturbines wonen, hebben vooral last van het geluid dat windturbines met zich meebrengen. Sommige mensen ervaren hinder (zoals irritatie, boosheid en onbehagen) als zij het gevoel hebben dat hun omgevingsof levenskwaliteit verslechtert door de plaatsing van windturbines.

  17. Otolith output - Project to study alternative life history types of fall Chinook based on otoliths

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The life-history complexity of Snake River fall Chinook salmon has hindered efforts to manage the ESU. In particular, the existence of an overwintering behavior in a...

  18. Identification of epileptic high frequency oscillations in the time domain by using MEG beamformer-based virtual sensors

    NARCIS (Netherlands)

    Van Klink, Nicole; Hillebrand, Arjan; Zijlmans, Maeike

    2016-01-01

    Objective: High frequency oscillations (HFOs, >80. Hz) are biomarkers for epileptogenic cortex in invasive and non-invasive electroencephalography (EEG). Identification of HFOs in magnetoencephalography (MEG) is hindered by noise. Computing spatial filters using beamforming to reconstruct time

  19. Analysis of archaeal communities in Gulf of Mexico dead zone sediments.

    Science.gov (United States)

    Sediments may contribute significantly to Louisiana continental shelf “dead zone” hypoxia but limited information hinders comparison of sediment biogeochemistry between norm-oxic and hypoxic seasons. Dead zone sediment cores collected during hypoxia (September 2006) had higher l...

  20. Eco-Governmentality: A Discursive Analysis of State-NGOs-Youth Relations in Singapore

    National Research Council Canada - National Science Library

    Peili Pey; Md Saidul Islam

    2017-01-01

    ...; state, NGOs and youths. By using eco-governmentality as a framework and through discursive analysis, we argue that state-society cooperation in environmentalism is hindered by lack of clear and effective communication...