151 resultados para TOTAL PARENTERAL-NUTRITION
Resumo:
The total synthesis of 8-isotestosterone (II) and the corresponding anthracene analogue (III) following the benzohydrindane route is reported. Catalytic hydrogenation of trans-1β-acetoxy-8-methyl-4,5-(3′-methyl-4′-hydroxybenzo)-hydrindane (V) followed by oxidation has furnished two isomeric tricyclic keto acetates, viz. 1β,2α-(3′-acetoxycyclopentano)-2,5-dimethyl-6-keto-1α,2,3,4,4aα,-5α,6,7,8,8aα-decahydronaphthalene (VII) and 1β,2α-(3′-acetoxycyclopentano)-2,5-dimethyl-6-keto-1α,2,3,4,4aβ,5,6,7,8,8aβ-decahydronaphthalene (IX) which are cis-non-steroid and cis-steroid configurations of the same cyclopentano-cis-decalins. A difference in the direction of enolization of the keto acetate (VII) in alkylation reaction and enol acetylation towards the methine and the methylene carbon atoms respectively has been observed.
Resumo:
This study considers the scheduling problem observed in the burn-in operation of semiconductor final testing, where jobs are associated with release times, due dates, processing times, sizes, and non-agreeable release times and due dates. The burn-in oven is modeled as a batch-processing machine which can process a batch of several jobs as long as the total sizes of the jobs do not exceed the machine capacity and the processing time of a batch is equal to the longest time among all the jobs in the batch. Due to the importance of on-time delivery in semiconductor manufacturing, the objective measure of this problem is to minimize total weighted tardiness. We have formulated the scheduling problem into an integer linear programming model and empirically show its computational intractability. Due to the computational intractability, we propose a few simple greedy heuristic algorithms and meta-heuristic algorithm, simulated annealing (SA). A series of computational experiments are conducted to evaluate the performance of the proposed heuristic algorithms in comparison with exact solution on various small-size problem instances and in comparison with estimated optimal solution on various real-life large size problem instances. The computational results show that the SA algorithm, with initial solution obtained using our own proposed greedy heuristic algorithm, consistently finds a robust solution in a reasonable amount of computation time.
Resumo:
Administration of chloromycetin has been found to enhance the oxygen uptake of the gut of the silkworm. The possibility that this increase might have been due to a thinning of the gut wall has been ruled out since the reduction in gut weight set in much later. Although glucose ultilization by the gut has been found to be increased in vitro, increase in oxygen uptake has not been affected in the presence of glucose. The possibility of a hormonal stimulation has been discussed.
Resumo:
Administration of chloromycetin has been found to enhance the oxygen uptake of the gut of the silkworm. The possibility that this increase might have been due to a thinning of the gut wall has been ruled out since the reduction in gut weight set in much later. Although glucose ultilization by the gut has been found to be increased in vitro, increase in oxygen uptake has not been affected in the presence of glucose. The possibility of a hormonal stimulation has been discussed.
Resumo:
The nature and extent of the influence of chloromycetin on larval digestion and utilization of the principal dietary constituents-the proteins, fats, and minerals-was studied. The antibiotic was shown to influence favourably the utilization of all the constituents studied. The results have been discussed in the light of these and other findings.
Resumo:
Although there is some information on the total amounts of proteins in wastewater and sludges1"3 and on the amino acids in them,4-11 especially in activated sludge,12 there is almost no evidence on the nature of the proteins in these materials. A knowledge of the nature of proteins in wastewater, sludges, and similar substances would be useful not only for determining the pollutional effects on the environment and the changes in the protein structures during decomposition or treatment, but also for determining the possible usage of the resulting materials in agriculture,13 includ ing animal nutrition.
Resumo:
Enantioselective formal total syntheses of the marine trisnorsesquiterpenes clavukerin A and isoclavukerin A, starting from (R)-limonene employing an RCM reaction as the key step, are described.
Resumo:
Enantiospecific total synthesis of optical antipode of the sesquiterpene 5-senecioyloxy-10,11-epoxythapsan-10-ol has been described. (R)-Carvone has been employed as the chiral starting material and a combination of intramolecular alkyation and Criegee fragmentation are employed for intramolecular stereospecific transfer of the chirality. An intramolecular diazoketone cyclopropanation and regioselective cyclopropane ring cleavage reactions have been employed or the creation of the three requisite contiguous quaternary carbon atoms.
Resumo:
Faraday rotation data obtained at Delhi, Kurukshetra, Hyderabad, Bangalore, Waltair, Nagpur and Calcutta during the total solar eclipse of 16 February 1980 and at Delhi during the total solar eclipse of 31 July 1981 have been analysed to detect the gravity waves generated by a total solar eclipse as hypothesized by Chimonas and Hines (1970, J. geophys. Res. 75, 875). It has been found that gravity waves can be generated by a total solar eclipse but their detection at ionospheric heights is critically dependent on the location of the observing station in relation to the eclipse path geometry. The distance of the observing station from the eclipse path should be more than 500 km in order to detect such gravity waves.
Resumo:
Enantiospecific total synthesis of (+)-pinguisenol 1, a sesquiterpene containing a cis-1,2,6,7-tetramethylbicyclo[4.3.0]nonane carbon framework incorporating two vicinal quaternary carbon atoms and four cis-oriented methyl groups on four contiguous carbon atoms, isolated from a liverwort, is described. The orthoester Claisen rearrangement of the allyl alcohol 9, obtained from (R)-carvone, generates the ester 12. Intramolecular cyclopropanation of the diazo ketone 13, derived from the ester 12, furnishes the tricyclic ketone 7. Degradation of the isopropenyl group followed by regioselective reductive cyclopropane ring cleavage transforms compound 7 into the hydroxy ketone 21. Wolff–Kishner reduction of the hydroxy ketone 21 followed by oxidation and Grignard reaction furnishes pinguisenol (+)- 1.
Resumo:
A facile synthesis of (+)-lentiginosine is accomplished from L-(+)-tartaric acid. Key transformations in the synthesis include the elaboration of gamma-oxo amide derived from tartaric acid.