1,223 research outputs found
Synthesis Of Novel 2-aryl-3-(2-morpholinoethyl)-1,3-thiazinan-4-ones Via Ultrasound Irradiation
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)This study describes the synthesis of fourteen thiazinanones from a multicomponent reaction of 2-morpholinoehtylamine (as primary amine), arenealdehydes (as carbonyl compound) and the mercaptopropionic acid using both conventional (thermal heating) and ultrasound methodologies. Through thermal heating methodology, the thiazinanones were obtained in 49 to 97% yields for 16 hours and through sonochemistry methodology, the reaction time was reduced for 25 minutes with yields 41 to 88%. The full identification and characterization of unpublished heterocycles were achieved by proton (H-1) and carbon 13 (C-13) nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry and infrared. Some of them were also characterized by elemental analysis.27611091115UFPelFAPERGS [11/2068-7]FAPESP [2013/18203-5]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP
Reversible speed control of one-stimulus-double-response, temperature-sensitive asymmetric hydrogel micromotors
Contains fulltext :
253695.pdf (Publisher’s version ) (Open Access)26 augustus 202
Synthesis of novel 2-aryl-3-(2-morpholinoethyl)-1,3-thiazinan-4-ones via ultrasound irradiation
This study describes the synthesis of fourteen thiazinanones from a multicomponent reaction of 2-morpholinoehtylamine (as primary amine), arenealdehydes (as carbonyl compound) and the mercaptopropionic acid using both conventional (thermal heating) and ultrasound methodologies. Through thermal heating methodology, the thiazinanones were obtained in 49 to 97% yields for 16 hours and through sonochemistry methodology, the reaction time was reduced for 25 minutes with yields 41 to 88%. The full identification and characterization of unpublished heterocycles were achieved by proton (1H) and carbon 13 (13C) nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry and infrared. Some of them were also characterized by elemental analysis27611091115CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DO RIO GRANDE DO SUL - FAPERGS307330/2012-5Sem informação2013/18203-511/2068-
Discovery of spin-phase dependent QPOs in the super-critical accretion regime from the X-ray pulsar RX J0440.9+4431
RX J0440.9+4431 is an accreting X-ray pulsar (XRP) that remained relatively
unexplored until recently, when major X-ray outburst activity enabled more
in-depth studies. Here, we report on the discovery of Hz
quasi-periodic oscillations (QPOs) from this source observed with -GBM.
The appearance of QPOs in RX J0440.9+4431 is thricely transient, that is, QPOs
appear only above a certain luminosity, only at certain pulse phases (namely
corresponding to the peak of its sine-like pulse profile), and only for a few
oscillations at time. We argue that this newly discovered phenomenon
(appearance of thricely transient QPOs -- or ATTO) occurs if QPOs are fed
through an accretion disk whose inner region viscosity is unstable to mass
accretion rate and temperature variations. Such variations are triggered when
the source switches to the super-critical accretion regime and the emission
pattern changes. We also argue that the emission region configuration is likely
responsible for the observed QPOs spin-phase dependence.Comment: 5 + 2 appendix pages. Accepted on A&A. Proofs versio
Induction of ebolavirus cross-species immunity using retrovirus-like particles bearing the Ebola virus glycoprotein lacking the mucin-like domain
<p>Abstract</p> <p>Background</p> <p>The genus <it>Ebolavirus </it>includes five distinct viruses. Four of these viruses cause hemorrhagic fever in humans. Currently there are no licensed vaccines for any of them; however, several vaccines are under development. Ebola virus envelope glycoprotein (GP<sub>1,2</sub>) is highly immunogenic, but antibodies frequently arise against its least conserved mucin-like domain (MLD). We hypothesized that immunization with MLD-deleted GP<sub>1,2 </sub>(GPΔMLD) would induce cross-species immunity by making more conserved regions accessible to the immune system.</p> <p>Methods</p> <p>To test this hypothesis, mice were immunized with retrovirus-like particles (retroVLPs) bearing Ebola virus GPΔMLD, DNA plasmids (plasmo-retroVLP) that can produce such retroVLPs <it>in vivo</it>, or plasmo-retroVLP followed by retroVLPs.</p> <p>Results</p> <p>Cross-species neutralizing antibody and GP<sub>1,2</sub>-specific cellular immune responses were successfully induced.</p> <p>Conclusion</p> <p>Our findings suggest that GPΔMLD presented through retroVLPs may provide a strategy for development of a vaccine against multiple ebolaviruses. Similar vaccination strategies may be adopted for other viruses whose envelope proteins contain highly variable regions that may mask more conserved domains from the immune system.</p
Lithium isotope evidence for enhanced weathering and erosion during the Paleocene-Eocene Thermal Maximum
The Paleocene-Eocene Thermal Maximum (PETM; ~55.9 Ma) was a geologically rapid warming period associated with carbon release, which caused a marked increase in the hydrological cycle. Here, we use lithium (Li) isotopes to assess the global change in weathering regime, a critical carbon drawdown mechanism, across the PETM. We find a negative Li isotope excursion of ~3‰ in both global seawater (marine carbonates) and in local weathering inputs (detrital shales). This is consistent with a very large delivery of clays to the oceans or a shift in the weathering regime toward higher physical erosion rates and sediment fluxes. Our seawater records are best explained by increases in global erosion rates of ~2× to 3× over 100 ka, combined with model-derived weathering increases of 50 to 60% compared to prewarming values. Such increases in weathering and erosion would have supported enhanced carbon burial, as both carbonate and organic carbon, thereby stabilizing climate
Formation of Well-Defined, Functional Nanotubes via Osmotically Induced Shape Transformation of Biodegradable Polymersomes
Contains fulltext :
161997.pdf (publisher's version ) (Open Access
A UML Reuse Framework and Tool for Requirements Engineering
Requirement Engineering (RE) activities are critical by nature and mostly manual. Some automated support for tasks helps requirements engineers to reduce manual labor and, consequently, reduce defects rates and increase reuse and motivation. In this paper, we introduce a UML framework and tool support which automates part of the RE process. Using UML stereotypes as the core of this solution, we created a set of integrated tools composed by: (1) a reusable framework that models RE behavior patterns that are typically present in information system projects; (2) a function that allows the reuse of information provided by entity modeling; (3) a tool that automates the generation of application prototypes; (4) a tool for counting IFPUG Function Points; and (5)a tool that analyzes specific types of defects. Our findings indicate that the framework and the automated support are effective at RE modeling and review. In addition, they increase motivation and promote team engagement, through elimination of repetitive activities.Sociedad Argentina de Informática e Investigación Operativ
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