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241,599 research outputs found

One pot facile synthesis of 5-alkyl-1,2-dihydro-spiro[4H-3, 1-benzoxazine- 2,3'[3H]indol]-4,2'-diones under microwave irradiation

Author: Saxena Anjali
Khanna Pankaj
Gupta Archana
Jain Subhash C
Bhagat Sunita
Publication venue
Publication date: 2006
Field of study

1504-1510A facile synthesis of some novel 5-alkyl-1,2-dihydro-spiro[4H-3, 1-benzoxazine-2,3'[3H]indol]-4,2'-diones, in high yields, has been carried out classically as well as under microwave irradiation in solvent free conditions. Microwave irradiation offers tremendous advantages in the form of shorter reaction time, operational simplicity, cleaner reaction, easy work-up and better yields as compared to the classical method. Besides this, some novel 6-alkylanthranilic acids required for the synthesis of new spiro compounds have also been synthesized. The importance of alkyl substituent at C-6 position in anthranilic acid has been recognized again in such a cyclocondensation reaction, even when it is carried out under microwave irradiation. This is also supported by molecular modeling. </span

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Synergies between processing and memory in children's reading span.

Author: Harvey Katarina
Horton Neil
Towse John N.
Hitch Graham J.
Publication venue
Publication date: 2010
Field of study

Previous research has established the relevance of working memory for cognitive development. Yet the factors responsible for shaping performance in the complex span tasks used to assess working memory capacity are not fully understood. We report a study of reading span in 7- to 11-year old children that addresses several contemporary theoretical issues. We demonstrate that both the timing and the accuracy of recall are affected by the presence or absence of a semantic connection between the processing requirement and the memoranda. Evidence that there can be synergies between processing and memory argues against the view that complex span simply measures the competition between these activities. We also demonstrate a consistent relationship between the rate of completing processing operations (sentence reading) and recall accuracy. At the same time, the shape and strength of this function varies with the task configuration. Taken together, these results demonstrate the potential for reconstructive influences to shape working memory performance among children

Lancaster E-Prints

The Effect of Lane Changing on Long-Span Highway Bridge Traffic Loading

Author: Carey Colm
B Enright
E OBrien
O\u27Brien Eugene J.
C Carey
O'Brien Eugene J.
Enright Bernard
C Caprani
Caprani Colin C.
Publication venue
Publication date: 10/04/2013
Field of study

Bridge Maintenance, Safety, Management, Resilience & Sustainability, Sixth International IABMAS Conference, Stresa, Lake Maggiore, Italy, 8-12 July 2012Maximum loading on long-span bridges typically occurs in congested traffic conditions. As traffic becomes congested car drivers may change lane, increasing the tendency for trucks to travel in platoons. For long-span bridges this phenomenon may increase the regularity and severity of bridge repair programs, with potential significant associated costs. This research investigates the effect of lane changing by car drivers on bridge loading. A Monte Carlo simulation model in which individual car drivers probabilistically decide, based on a lane-changing bias probability, whether or not to change lane has been developed. The sensitivity of bridge loading to this factor is investigated for different bridge lengths and traffic compositions. This research concludes that the lane-changing behavior of car drivers has an effect on bridge loading for long-span bridges, and the magnitude of this effect is quite sensitive to the percentage of trucks in the traffic.Deposited by bulk impor

Crossref

Research Repository UCD

Irish Universities

Steel pedestrian bridge with span 15 m

Author: Picej Mitja
Publication venue
Publication date: 07/08/2013
Field of study

Ta dokument vsebuje statično analizo in dimenzioniranje jeklenega mostu za pešce razpona 15 m in širine 3,5 m skladno z Evrokod standardi. Dokument vsebuje dimenzioniranje vzdolžnih in prečnih jeklenih HEA profilov, armirano-betonskega stebra, temelja in lesene pohodne površine. Na kratko so opisani tudi sestavni deli mostne konstrukcije.This document presents a dimensioning of a steal pedestrian bridge with 15 m span and 3,5 m width. The dimensioning is made in accordance with the Eurocode standards. This document contains dimensioning of steal longitudinal HEA profiles, reinforced concrete pillar and the foundation as well as the wooden walking surface. The main parts of bridge structure are also shortly described

Digital library of University of Maribor

Is ab initio DFT method useful in analyzing sequence specificity of bases in nucleic acid?

Author: Kalita Rituraj
Medhi C
Parajuli Raghab
Publication venue
Publication date: 2006
Field of study

782-791The stacking interaction of base pairs in DNA has been studied by using DFT method. The results obtained from DFT study are complementary to those of ab initio and semi-quantitative studies, and subsequently useful for analyzing sequence specificity among various sequences in DNA, The interaction energies of optimum stacked base pairs are higher than those of ab initio and semi-quantitative results, but significant variation of interaction energies of different sequence combination is observed. The stacked models, AT-AT, AT-TA, GC-GC, GC-CG, AT-GC and AT-CG combinations indicate some stabilization at different twist angles. The results obtained from DFT method clearly show some electrostatic interaction energies associated in each stacked model, although provide small interaction energies due to the exclusion of dispersion interaction. </span

NOPR

A new sesguiterpene glycoside from the roots of Pteris multifida Poir

Author: Hu Haobin
Zheng Xudong
Jian Yufeng
Cao Hong
Liu Jianxin
Publication venue
Publication date: 2006
Field of study

1274-1277A new sesquiterpene glycoside, multifidoside C 1, along with four known compounds have been isolated from the roots of Pteris multifida. By spectral evidence, the structure of the new compound has been elucidated as eudesm-4 (15)-ene-1β, 8α-diol 8-O-β-D-xylopyranosyl-(1→6)-β-D-glucopyranoside. The known compounds are identified to be plumbagic acid 2, 1,5,8- trihydroxy-3-methoxyxanthone 8-O-D-glucopyranoside 3, eusiderin 4, and neesiinoside B 5, All compounds except 3 have been initially isolated from Pteris multifida. </span

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Driving in the wrong lane: towards a longer life-span of cars

Author: T Cooper (9861518)
Rodrigues A
Cooper T
A Rodrigues (3216246)
Watkins M
M Watkins (13630186)
Publication venue
Publication date: 01/01/2015
Field of study

Within the context of product longevity, one especially impactful and ubiquitous product demands further research: the car. Car longevity has been addressed in the context of product life extension and product lifetime optimisation but there have been a few studies on car longevity in the context of business and none specifically from an industrial design context. This paper presents initial findings from preliminary interviews with key industry representatives such as car designers and engineers. It discusses the barriers to and opportunities for designing a car with a longer life-span. This and further data will later be analysed in order to produce a design framework to inform car designers on life-span and usage optimization through design. Strategies such as increased longevity or use-intensity can potentially reduce the throughput - and thereafter the consumption - of cars. Such a shift in the automotive sector would support the transition from a linear economy to a more sustainable one. The initial findings, however, suggest that a longer life car is not an uncompromised solution and important concessions would have to be made in order to make this an acceptable product

Nottingham Trent Institutional Repository (IRep)

Sussex Research Online

Pyrazolo-fused quinoline analogues: Synthesis of 1H-pyrazolo [3, 4-b] quinolines and 3-amino-1H-pyrazolo [3, 4-b] quinolines from 3-formyl and 3-cyano-2- <span style="font-size:12.0pt;font-family:"Times New Roman";mso-fareast-font-family: "Times New Roman";mso-bidi-font-family:"Times New Roman";color:black; mso-ansi-language:EN-IN;mso-fareast-language:EN-IN;mso-bidi-language:HI">chloroquinolines

Author: Srivastava Ambika
Singh Mrityunjay K
Singh R M
Publication venue
Publication date: 2006
Field of study

292-296Stepwise synthesis of 1H-pyrazolo [3, 4-b] quinolines 6 has been described from the reactions of 2-chloro-3- formylquinolines 1 with cthyleneglycol and hydrazine hydrate reagents in sequence followed by hydrolysis with BiCI3. However, 3-amino-1H-pyrazolo[3, 4-b]quinolines 7 have been synthesized from 2-chloro-3-cyanoquinolines 2 with excess of hydrazine hydrate in one step. The functional group manipulation of amino group in compounds 7 has also been studied. </span

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The life span development of decision making

Author: Josef A.
Josef Anika K.
Publication venue
Publication date: 01/01/2016
Field of study

Die vorliegende Dissertation setzt sich mit der Lebensspannenentwicklung von Entscheidungsverhalten auseinander. Sie beschäftigt sich insbesondere damit, wie sich das Zusammenspiel von Umwelt und Kognition auf Entscheidungen auswirkt, wenn Personen älter werden. Dabei liegt ein Schwerpunkt auf der Lebensspannenentwicklung der Bereitschaft Risiken einzugehen (drei Manuskripte) und ein weiterer darauf, zu untersuchen, wie sich steigende kognitive Anforderungen beim Treffen von Entscheidungen auf Altersunterschiede der Entscheidungsqualität auswirken (ein Manuskript). Im ersten Manuskript, „Stability and change in risk-taking propensity across the adult lifespan“ wird anhand eines repräsentativen Längsschnittdatensatzes untersucht, wie sich die Bereitschaft Risiken einzugehen in Abhängigkeit des Lebensbereiches und über die Lebensspanne verändert. Die Resultate zeigen, dass die Risikobereitschaft Charakteristika ähnlich zu denen eines Persönlichkeitsmerkmals aufweist: Am unteren und oberen Ende der Lebensspanne ist die individuelle Stabilität über die Zeit hinweg im Vergleich zum mittleren Alter am geringsten. Die Risikobereitschaft nimmt im Mittel jedoch ab und diese Abnahme ist nicht in jedem Lebensbereich gleich. Die individuelle Veränderung der Risikobereitschaft über die Zeit steht mit individuellen Veränderungen anderer Persönlichkeitsmerkmale wie Extraversion und Offenheit für Erfahrungen in Zusammenhang. Das zweite Manuskript „Age differences in risk-taking propensity are related to perceptions of risk and reward but not perceived control“ untersucht mögliche psychologische Mechanismen hinter der alters- und bereichsspezifischen Veränderung der Risikobereitschaft. Anhand eines weiteren repräsentativen Datensatzes wird analysiert, in wie weit altersbedingte Veränderungen in der Wahrnehmung von Risiko, Nutzen, und Kontrolle in verschiedenen Lebensbereichen eine Rolle spielen. Die Resultate zeigen, dass eine veränderte Wahrnehmung von Kosten und Nutzen die Veränderungen erklären können, nicht jedoch eine veränderte Kontrollwahrnehmung. Das dritte Manuskript „Propensity for risk taking across the life span and around the globe“ untersucht, ob die generelle mittlere Abnahme der Risikobereitschaft für Menschen auf der ganzen Welt gültig ist. Die Annahme ist, dass Merkmale wie Armut, Mordrate, und Einkommensungleichheit Einfluss auf die individuelle Risikobereitschaft nehmen, weil Menschen, in Ländern in denen Ressourcen knapp sind, stärker miteinander konkurrieren müssen als Menschen in Ländern, in denen dies nicht der Fall ist. Die Ergebnisse zeigen einen deutlichen Zusammenhang zwischen der Situation in einem Land und der Abnahme der Risikoneigung über die Lebensspanne. Das vierte Manuskript „How cognitive aging affects decision making under increased memory demands“ untersucht, wie sich steigende kognitive Anforderungen beim Treffen von Entscheidungen auf Altersunterschiede in der Entscheidungsqualität und die Strategieselektion auswirken. Gedächtnisfähigkeiten unterliegen einer stetigen Veränderung über die Lebensspanne und insbesondere ältere Personen zeigen Defizite in der Erinnerungsleistung. Die Ergebnisse zeigen, dass mit zunehmenden Gedächtnisanforderungen, Altersunterschiede in der Entscheidungsqualität größer werden. Individuelle Gedächtnisfähigkeiten mediierten diesen Zusammenhang. Die Ergebnisse sind zudem dadurch zu erklären, dass ältere Erwachsene im Vergleich zu jüngeren Erwachsenen in geringerem Maße zu kompensatorischen Entscheidungsstrategien wählen. Insgesamt unterstreichen die Ergebnisse dieser Dissertation, dass für die Untersuchung von Phänomenen menschlicher Entwicklung das Zusammenspiel von Mensch und Umwelt berücksichtigt werden muss. Diese Dissertation zeigt, dass Veränderungen dieser Phänomene, wie zum Beispiel menschliches Entscheidungsverhalten, oft eine Anpassungsleistungen des Menschen an unterschiedliche Lebensbereiche, kulturelle Umwelten, oder an eine sich verändernde kognitive Leistungsfähigkeit sind. Abstract Individuals of all ages are often confronted with situations varying in their complexity and situational characteristics. Normal aging is associated with changes in cognitive capacities such as learning and memory but also notable alterations in physical fitness, health, and the social environment. These changes most likely affect not only the necessary cognitive tools but also the perception of gains and losses in relation to available resources and personal goals when making decisions. This dissertation shows that age differences in decision making cannot be understood without considering the fit between the individual resources and the characteristics of the choice environment. It comprises three papers studying the effect of aging on the propensity to take risks as well as one paper on inference decisions in choice ecologies that differ in memory demand. The first paper investigates longitudinal changes in risk-taking propensity across the life span. It shows that the propensity to take risks varies as a function of age and domain. Interestingly, different conceptions of change suggest that risk-taking propensity has trait-like properties similar to those found in major personality traits such as the Big Five. The second paper studies the psychological mechanisms of age- and domain-differences in risk-taking propensity. It finds that individual differences in the perceptions of costs and benefits, but not control beliefs, account for the prominent age-related but domain-variant change in risk-taking propensity. The third paper presents a cross-cultural investigation of life span changes in risk-taking propensity. It suggests that age-related changes in risk taking are associated with local characteristics: Countries in which hardship (i.e., homicide rate, gross domestic product, income/gender inequality) is largest show least changes in risk-taking propensity over the life span. Finally, the fourth paper summarizes empirical studies on the effects of memory demand on age differences in inference decisions. It displays that individual memory ability is crucial for the maintenance of adequate decision outcomes in choice environments that pose high demands on memory. Overall, these findings emphasize that in order to predict life span changes in decision making, one needs to take the interaction between the individual and the environment into account. Developmental phenomena such as changes in decision making can be understood as individual efforts to adapt one’s performance to both internal and external changes such as in the environment surrounding them or their own motivations and cognitive capacity

edoc

MPG.PuRe

Synthesis, structure and luminescence behaviour of complexes of type [Cd(dpa)2X2] (dpa = 2,2'-djpyridylamine; X = N3-, NCS-, NCO-)

Author: Ghosh Barindra K
Chowdhury Habibar
Rosair Georgina M
Ghosh Rajarshi
Rahaman Sk Hafijur
Publication venue
Publication date: 2005
Field of study

687-692The synthetic details and characterization data of three mononuclear complexes or the type [Cd(dpa)2X2] (dpa = 2,2'-dipyridylamine; X = N3-, NCS-, 2 and X-NCO-,3) are described. In one case, [Cd(dpa)2(NCS)2 (2), X-ray structure determination has been made for the exact definition of the coordination sphere. Structural analysis reveals that the cadmium(II ) centre is in a distorted octahedral environment with a CdN5S chromophore with two dpa units roughly perpendicular to one another and the two thiocyanates in mutual cis orientation with one in S-bound and the other in N-bound states. The mononuclear unit packs through N-H ... S and N-H- ... N hydrogen bonding to have a one-dimensional (ID) chain. Spectroscopic and other physicochemieal data show that compounds 1 and 3 have the cognate structure. The compounds display high energy intraligand 1(π- π *) fluorescence and intraligand 3(π- π *') phosphorcscence in glassy solutions (DMF at 77 K). A band (near 375 nm) observed for all the complexes in their solid state emission spectra is an excimeric emission. The role of dpa, a tailored diimine with active amine hydrogen and aromatic pyridine ring, is discussed towards functionalisation on crystal engineering and luminescence behaviour. </span

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