Acetoxymaleic Anhydride as Ketene Equivalent in the Diels-Alder Reaction

Acetoxymaleic anhydride (AMA) has been shown to be a versatile ketene equivalent in the Diels-Alder reaction for the conversion of 1,3-dienes into cyclohexanones. The new transformation has been applied to an alternate synthesis of methyl cis-dihydrojasmonate, an important jasmine fragrance, and to several model systems

Strictosidine, the common precursor for monoterpenoid indole alkaloids with 3 α and 3 β configuration

Recently we reported that strictosidine (l> is the key intermediate in the formation of the three classes (ASDidOf3DeIm5, Iboga, Corynanthe) of monoterpenoid indole alkaloids In Catharanthus roseus and a variety of other plant species in cell culture using in vivo and in vitro techniques"2. These results were independently confirmed In Manchester 394 and subsequently also Scott et a1.5 were able to confirm the precursor role of (1) using Catharanthus material. All these results are in accord with reports on the biosynthesis of an alkaloid of taxonomically distant origin, camptothecln, for which strictosidine la&am6 was previously found to be a precursor, and recently7 also (1). The key intermediate in the biosynthesis of the majority of mono-terpenoid alkaloids is therefore (1) with 3 a (2) configuration, rather than vincoside (2) with 3 13 (lX> configuration as had previously been assumeda. However, a generalization of this precursor function of (1

Corpos em transparência: útero-feto-psiquismo: sobre a experiência do ultra-som obstétrico no processo de parentalização

The purpose of this work was to investigate the way in which the visualization of the baby during an obstetric ultrasound exam interferes with the process of parenting during the pregnarcy, as well as, to verify the concepts formed by obstetric ultrasound examiners about their own function, as well as the influence on pregnant women of the exam as an experience. We selected twelve pregnant women, all 19 years of age or older, either primiparous or multiparous. We have followed twelve exams proceeded by three doctors (four exams each). Each patient, as well as the three doctors, was observed during the ultrasound exam, followed by an individual semi-directive interview.O presente trabalho visa verificar de que forma a visualização do bebê durante o exame de ultra-sonografia obstétrica interfere no processo de parentalização da gestante. Foram selecionadas doze gestantes, com idades acima de 19 anos, primíparas ou multíparas. Cada sujeito teve um exame de ultrasom observado, participando em seguida de uma entrevista individual, semidiretiva. Além das gestantes, os três médicos que tiveram seus exames observados foram também entrevistados, no intuito de investigar a compreensão que o ecografista tem sobre sua função na ultra-sonografia obstétrica, e sobre a influência da experiência do exame para a gestante, considerando-se os efeitos do ultra-som para O processo de construção da parentalidade

Replacement Sequence of Events Generator

The soeWINDOW program automates the generation of an ITAR (International Traffic in Arms Regulations)-compliant sub-RSOE (Replacement Sequence of Events) by extracting a specified temporal window from an RSOE while maintaining page header information. RSOEs contain a significant amount of information that is not ITAR-compliant, yet that foreign partners need to see for command details to their instrument, as well as the surrounding commands that provide context for validation. soeWINDOW can serve as an example of how command support products can be made ITAR-compliant for future missions. This software is a Perl script intended for use in the mission operations UNIX environment. It is designed for use to support the MRO (Mars Reconnaissance Orbiter) instrument team. The tool also provides automated DOM (Distributed Object Manager) storage into the special ITAR-okay DOM collection, and can be used for creating focused RSOEs for product review by any of the MRO teams

Oscillations and velocity structure of a long-lived cyclonic spot

Dark brown cyclonic spots ('barges') at 14°N were studied by using Voyager 1 and 2 images of Jupiter. Movie sequences were made to study the spots' behavior over intervals of 50 days and longer. These movies revealed that the length and width vary by ±9% with a period of about 15 days, while the area remains approximately constant. The horizontal velocity field was investigated for an interval of about 1 day. Flow around the largest barge (feature 6) occurs as a ring current. The vorticity inferred is about 2½ times that of the ambient cyclonic zonal circulation, and about one-half the value of the local planetary vorticity. Length and width variations appear to be associated with a nonzero horizontal divergence field. If the oscillations are a natural mode of the system, the 15-day period will provide an important datum for testing models of stable closed vortices

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Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68187/2/10.1177_074171365500600102.pd

The Pre-Biblical Metallurgical Art on the Biblical Territory

The Old Testament describes in detail the metallurgical achievements, both in the period before the conquest and colonization of the promised land (mostly related to the manufacturing of the Tabernacle, in this sense, the gold chandelier with seven branches, also known as the menorah, is an exceptional example), and the period after the conquest and colonization of the promised land (the sea of bronze pillars Boaz and Jachin, the 10 golden candlesticks with seven arms, etc., famous artifacts of Solomon's Temple facilities, are good examples). Question: at that time, did the Jews have the technical and technological knowledge necessary to create things in order to reach the great achievements of the metallurgical processes described in the Old Testament? This article tries to answer this question

Heavy Metal Ions Cu (II), Co (II) and Cr (III) Bifunctionally Improved with Hydroxamic and Amidoxime Groups Chelating Ion Exchangers

Two new types of bifunctional chelating ion exchangers on the basis of ethylacrylate acrylonitrile: divinylbenzene copolymers with hydroxamic acid and amidoxime groups have been evaluated for Cu(II), Co(II) and Cr(III)ions sorption from unbuffered diluted aqueous solutions. To model the retention and to compare the sorption capacity of bifunctional acrylic chelating sorbents for the tested cations the Langmuir and Freundlich isotherm equations have been used. The Langmuir maximum sorption capacities for the sorbent of type A were determined to be 2.081, 1.423 and 1.384 mmole/g for Cu (II), Co (II) and Cr (III), respectively. The increase of cross- linking degree for the bifunctional chelating ion exchanger of type B resulted in the decrease of its sorption capacity toward heavy metal ions under study. The negative values of ΔG in all cases point to the spontaneous character of the sorption process. The kinetics of the Cu (II), Co (II) and Cr (III) sorption follows the Lagergren pseudo – first order model. The results are significant for the future development of the tested sorbents into beneficial materials for industrial and environmental applications

Spectrophotometric Determination of Os(VIII) with Nitroso R Salt as Chromogenic Reagent

Several methods have been reported for the spectrophotometric determination of osmium with various chromogenic reagents. Some of these reagents react slowly with osmium and the conditions for obtaining reproductibile colours are usually empirical. In this context, a simple and sensitive spectrophotometric method for the determination of trace amounts of osmium(VIII) using disodium-1-nitroso-2-hydroxynaphthalene-3,6-disulphonate (Nitroso R salt) is described. The method is based on the formation of an Os–Nitroso R salt complex which exhibits two different colours as function of pH. Linear calibration graphs are obtained up to 60 μg/mL of the analyte at pH = 4.8. The stoichiometry of the complex is found to be 1: 4 by mole ratio method. The method is optimized and different analytical parameters were evaluated. For instance, the calculated values for the molar absorptivity are of 3.645.103 L/mol.cm (pH = 0; λ = 550 nm) and 1.695.103 L/mol.cm (pH = 4.8; λ = 510 nm), respectively. The proposed method should be valuable for the determination of osmium(VIII) with good accuracy and precision