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Relevant bibliographies by topics / Mechanism of 2-methyl-1,3-dioxolane

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Academic literature on the topic 'Mechanism of 2-methyl-1,3-dioxolane'

Author: Grafiati

Published: 4 June 2021

Last updated: 13 February 2022

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Journal articles on the topic "Mechanism of 2-methyl-1,3-dioxolane"

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Schweitzer, L., J. Noblet, E. Ruth, and I. H. Suffet. "The Formation, Stability, and Odor Characterization of 2-ethyl-4-methyl-1,3-dioxolane (2-EMD)." Water Science and Technology 40, no. 6 (September 1, 1999): 293–98. http://dx.doi.org/10.2166/wst.1999.0312.

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A class of compounds which are byproducts of the resin manufacturing process, has been responsible for three different taste and odor episodes in drinking water around the world. One such episode which occurred on the Ohio River, Pennsylvania, USA in 1989 was linked to the chemical, 2-ethyl-4-methyl-1,3-dioxolane (2-EMD). In this study, the mechanism and kinetics of formation of 2-EMD were examined specifically under the conditions which were present in the waste water of a resin manufacturer during the Ohio River event. The stability (fate) of 2-EMD was studied at aqueous pHs of 3, 5, 7, and 9. Hydrolysis occurred on the order of hours at pH 3 and its stability was questionable even at pH 7, but appeared to be stable at pH 9. 2-EMD was synthesized and purified in order to determine odor characteristics and odor thresholds using the method of flavor profile analysis (FPA). The distinctive sweet odor described as “sickening sweet” or “medicinal sweet” was found to have an odor threshold concentration of between 5 and 10 ng/l. The levels of 2-EMD found in drinking water samples from the taste and odor event of the Ohio River were above this odor threshold.

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Kaválek, Jaromír, Vladimír Macháček, Miloš Sedlák, and Vojeslav Štěrba. "Study of Cyclization of 1-Benzoyl-3-methyl-3-(2-methoxycarbonylphenyl)thiourea to 1-Methyl-2-thioxo-4-quinazolone." Collection of Czechoslovak Chemical Communications 58, no. 5 (1993): 1122–32. http://dx.doi.org/10.1135/cccc19931122.

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The reaction mechanism of the title reaction was proposed on the bases of the kinetic study. The reaction takes place in two stages considerably differing in rates. In the first, faster stage, the anion of initial substance cyclizes to 1-methyl-3-benzoyl-2-thioxo-4-quinazolone. The reaction is reversible, the concentration of 1-methyl-3-benzoyl-2-thioxo-4-quinazolone decreases with increasing concentration of methanolate. In the second stage, the benzoyl group rearrangement in the given substance from nitrogen to sulfur and subsequent methanolysis to 1-methyl-2-thioxo-4-quinazolone take place. The rate-determining step is the methanolysis for [CH3O(-)] < 4 . 10-3 mol l-1 and the benzoyl group rearrangement for higher methanolate concentrations.

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Arnold, Donald R., Laurie J. Lamont, and Allyson L. Perrott. "1,n-Radical ions. Photosensitized (electron transfer) carbon–carbon bond cleavage. Formation of 1,6-radical cations." Canadian Journal of Chemistry 69, no. 2 (February 1, 1991): 225–33. http://dx.doi.org/10.1139/v91-036.

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The reactivity of the radical cations of methyl 2,2-diphenylcyclohexyl ether (7), 6,6-diphenyl-1,4-dioxaspiro[4.5]decane (8), methyl cis- and trans-2-phenylcyclohexyl ether (9cis and trans), and 6-phenyl-1,4-dioxaspiro[4.5]decane (10), generated by photosensitized (electron transfer) irradiation, has been studied. Solutions of the ethers and acetals in acetonitrile–methanol (3:1), with 1,4-dicyanobenzene (2) serving as the electron acceptor, were irradiated with a medium-pressure mercury vapour lamp through Pyrex. The diphenyl derivatives 7 and 8 were reactive; 7 gave 6,6-diphenylhexanal dimethyl acetal (11) and 8 gave 2-methoxy-2-(5,5-diphenylpentyl)-1,3-dioxolane (12). These are the products expected from the intermediate 1,6-radical cation, formed upon carbon–carbon bond cleavage of the cyclic radical cation. The monophenyl derivatives 9cis and trans and 10 were stable under these irradiation conditions. The mechanism for the carbon–carbon bond cleavage and for the cis–trans isomerization is discussed. An explanation, based upon conformation, is offered for the lack of reactivity of 9 and 10. Molecular mechanics (MM2) calculations were used to determine the preferred conformation of 9cis and trans, and 10. Key words: photosensitization, electron transfer, radical cation, carbon–carbon bond cleavage, conformation.

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Calmanti, Roberto, Emanuele Amadio, Alvise Perosa, and Maurizio Selva. "Reaction of Glycerol with Trimethyl Orthoformate: Towards the Synthesis of New Glycerol Derivatives." Catalysts 9, no. 6 (June 14, 2019): 534. http://dx.doi.org/10.3390/catal9060534.

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The reactivity of glycerol with trimethyl orthoformate is here described with an emphasis on developing a reliable synthetic approach for glycerol valorization. The glycerol based orthoester 4-(dimethoxymethoxy)methyl)-2-methoxy-1,3-dioxolane (3) was synthesized, under catalytic as well as catalyst-free conditions, by taking advantage of the thermodynamically controlled equilibrium between intermediates. Both Brønsted and Lewis acid catalysts accelerated the attainment of such an equilibrium, particularly Brønsted acidic ionic liquids BSMImHSO4 and BSMImBr were the most effective compounds for this reaction. The kinetic profiles allowed the proposal of a mechanism that accounts for the selectivity of the reaction.

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Popsavin, Velimir, Ljubica Radic, Mirjana Popsavin, and Vera Cirin-Novta. "Unexpected cycloreversion of a tosylated sugar oxetane under E2 conditions: The facile formation of 2-(2-furanyl)-1, 3-dioxolane from a novel 2, 5:4, 6-dianhydro-L-idose derivative (Preliminary commun." Journal of the Serbian Chemical Society 69, no. 2 (2004): 117–22. http://dx.doi.org/10.2298/jsc0402117p.

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2,5:4,6-Dianhydro-3-O-p-toluenesulfonyl-L-idose ethylene acetal (4) was synthesized with the aim of studying its chemical behaviour in the presence of several basic agents (Bu4NF/MeCN, NaOMe/MeOH, KOBut/ButOH/THF, and NaH/DMSO). Treatment of 4 with sodium hydride in dimethyl sulphoxide at room temperature unexpectedly gave the 2-(2-furanyl)-1,3-dioxolane. The mechanism of the process presumably involved the initial conversion of 4 to the corresponding 2,3-unsaturated derivative 5, followed by a facile oxetane ring cycloreversion by the elimination of formaldehyde.

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Rejňák, Michal, Jiří Klíma, Jiří Svoboda, and Jiří Ludvík. "Synthesis and Electrochemical Reduction of Methyl 3-Halo-1-benzothiophene-2-carboxylates." Collection of Czechoslovak Chemical Communications 69, no. 1 (2004): 242–60. http://dx.doi.org/10.1135/cccc20040242.

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A preparative method of synthesis of the new methyl 3-iodo-1-benzothiophene-2-carboxylate was elaborated. Electrochemical behavior of methyl 3-chloro-, bromo- and iodo-1-benzothiophene-2-carboxylates 1-3, and of their reduction and dimer products 4, 5 in anhydrous dimethylformamide has been investigated at mercury and platinum electrodes using polarography, cyclic voltammetry and voltammetry on a rotating platinum disk electrode. The reduction in divided cells follows the ECE mechanism (electron - chemical step - electron), where the primary radical anion is split into a halide anion and neutral heterocyclic radical, which is immediately reduced by the second electron and protonated. The only reduction product is the methyl 1-benzothiophene-2-carboxylate (5); whereas the EDim mechanism (electron - dimer formation) leading to the dimeric species 4 was not observed under the above conditions. Reduction of 1-3 on platinum causes formation of a blocking film on the electrode. Sonication during electrolysis successfully reactivates the electrode.

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Kaválek, Jaromír, Josef Jirman, and Vojeslav Štěrba. "Kinetics and mechanism of rearrangement and methanolysis of acylphenylthioureas." Collection of Czechoslovak Chemical Communications 50, no. 3 (1985): 766–78. http://dx.doi.org/10.1135/cccc19850766.

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S-Acyl-1-phenylthioureas and their 3-methyl derivatives are rearranged to 1-acyl derivatives of thiourea in methanolic solution. The rearrangement of the 1-acyl-1-phenyl derivative to the thermodynamically more stable 3-acyl derivative is subject to specific base catalysis. The rearrangement of acetyl group is about 2 orders of magnitude slower than that of benzoyl group. 1-Acetyl-l-phenylthiourea undergoes base-catalyzed methanolysis (giving phenylthiourea and methyl acetate) instead of the rearrangement. The methanolysis rates of l-acyl-3-phenylthioureas and their N-methyl derivatives have been measured. The acetylthioureas react at most 3x faster than the benzoyl derivatives. The methyl group at the nitrogen adjacent to acyl group accelerates the solvolysis by almost 2 orders of magnitude; the methyl group at the other nitrogen atom retards the solvolysis by almost 1 order of magnitude. Replacement of hydrogen atom by methyl group at the phenyl-substituted nitrogen increases acidity of the phenylacetylthiourea by 2 orders of magnitude. The same replacement at the benzoyl-substituted nitrogen increases the acidity by 3 orders of magnitude, the increase in the case of the acetyl derivative being as large as 4 orders of magnitude.

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Gu, Zhengxian, Mark A. Wainberg, Nghe Nguyen-Ba, Lucille L’Heureux, Jean-Marc de Muys, Terry L. Bowlin, and Robert F. Rando. "Mechanism of Action and In Vitro Activity of 1′,3′-Dioxolanylpurine Nucleoside Analogues against Sensitive and Drug-Resistant Human Immunodeficiency Virus Type 1 Variants." Antimicrobial Agents and Chemotherapy 43, no. 10 (October 1, 1999): 2376–82. http://dx.doi.org/10.1128/aac.43.10.2376.

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ABSTRACT (−)-β-d-1′,3′-Dioxolane guanosine (DXG) and 2,6-diaminopurine (DAPD) dioxolanyl nucleoside analogues have been reported to be potent inhibitors of human immunodeficiency virus type 1 (HIV-1). We have recently conducted experiments to more fully characterize their in vitro anti-HIV-1 profiles. Antiviral assays performed in cell culture systems determined that DXG had 50% effective concentrations of 0.046 and 0.085 μM when evaluated against HIV-1IIIB in cord blood mononuclear cells and MT-2 cells, respectively. These values indicate that DXG is approximately equipotent to 2′,3′-dideoxy-3′-thiacytidine (3TC) but 5- to 10-fold less potent than 3′-azido-2′,3′-dideoxythymidine (AZT) in the two cell systems tested. At the same time, DAPD was approximately 5- to 20-fold less active than DXG in the anti-HIV-1 assays. When recombinant or clinical variants of HIV-1 were used to assess the efficacy of the purine nucleoside analogues against drug-resistant HIV-1, it was observed that AZT-resistant virus remained sensitive to DXG and DAPD. Virus harboring a mutation(s) which conferred decreased sensitivity to 3TC, 2′,3′-dideoxyinosine, and 2′,3′-dideoxycytidine, such as a 65R, 74V, or 184V mutation in the viral reverse transcriptase (RT), exhibited a two- to fivefold-decreased susceptibility to DXG or DAPD. When nonnucleoside RT inhibitor-resistant and protease inhibitor-resistant viruses were tested, no change in virus sensitivity to DXG or DAPD was observed. In vitro drug combination assays indicated that DXG had synergistic antiviral effects when used in combination with AZT, 3TC, or nevirapine. In cellular toxicity analyses, DXG and DAPD had 50% cytotoxic concentrations of greater than 500 μM when tested in peripheral blood mononuclear cells and a variety of human tumor and normal cell lines. The triphosphate form of DXG competed with the natural nucleotide substrates and acted as a chain terminator of the nascent DNA. These data suggest that DXG triphosphate may be the active intracellular metabolite, consistent with the mechanism by which other nucleoside analogues inhibit HIV-1 replication. Our results suggest that the use of DXG and DAPD as therapeutic agents for HIV-1 infection should be explored.

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Abell, AD, and RA Massy-Westropp. "Mechanism of Acetal Cleavage with Methylmagnesium Iodide." Australian Journal of Chemistry 38, no. 7 (1985): 1031. http://dx.doi.org/10.1071/ch9851031.

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The reaction of methylmagnesium iodide with methyl (1R,3S,5R)-1-(furan- 3′-yl)-5-methyl-2,8-dioxabicyclo[3.2.1]octane-3-carboxylate (2) gives products arising from regioselective carbon-oxygen bond fission and intermolecular transfer of the methyl group of the Grignard reagent to the intermediate oxocarbonium ion, in addition to the usual tertiary alcohol.

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Brown, D. Sean, Jason V. Jollimore, Marcus P. Merrin, Keith Vaughan, and Donald L. Hooper. "Formation of methyl 2-arylhydrazono-3-oxobutanoates and 2-arylhydrazono-3-oxobutanenitriles during the coupling reaction of arenediazonium ions with methyl 3-aminocrotonate and 3-aminocrotononitrile." Canadian Journal of Chemistry 73, no. 2 (February 1, 1995): 169–75. http://dx.doi.org/10.1139/v95-025.

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Reaction of aryldiazonium salts with methyl 3-aminocrotonate (1) affords high yields of the methyl 2-arylhydrazono-3-oxobutanoates (4); analogous diazonium coupling with 3-aminocrotononitrile (2) gives the 2-arylhydrazono-3-oxobutanenitriles (5). The hydrazones are the product of diazonium coupling at the C2-vinylic carbon, concomitant with hydrolysis of the 3-amino substituent to the 3-oxo derivative; there is no evidence for the formation of a triazene (6), which would be the product of N-coupling. All hydrazones (4a–e and 5a–d) have been fully characterized by IR and 1H and 13C NMR spectroscopy; the NMR spectra of the methyl 2-arylhydrazono-3-oxobutanoates (4) suggest the presence of two isomeric intramolecularly H-bonded forms in solution. Selected compounds were further characterized by elemental analysis and mass spectrometry. A mechanism is proposed for the conversion of 1 or 2 into 4 or 5, and these observations are compared with previously reported observations of diazonium coupling reactions with unsaturated systems. Keywords: hydrazone, diazonium, aminocrotonate, aminocrotononitrile, hydrogen bonding.

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Dissertations / Theses on the topic "Mechanism of 2-methyl-1,3-dioxolane"

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Kesaboina, Sirisha R. "Kinetics and Chemical Reactions of Acetaldehyde Stripping and 2-methyl-1,3-dioxolane Generation in Poly(ethylene terephthalate)." University of Toledo / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1304096768.

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Karmal, Said. "Caractérisation des catalyseurs CoMo/Al(2)O(3) sulfurés à l'aide de réactions modèles." Poitiers, 1988. http://www.theses.fr/1988POIT2313.

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Zhou, Xi. "Mechanisms of inhibition of cell proliferation by 1-O-octadecyl-2-O-methyl-sn-glycero-3-phosphocholine in epithelial cancer cell lines." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq23680.pdf.

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BELLOSTA, DECHAVANNE VERONIQUE. "Contribution a l'etude de la reactivite de derives glucidiques vis-a-vis d'organometalliques : nouvelles syntheses stereospecifiques de c-glycosides." Paris 6, 1987. http://www.theses.fr/1987PA066256.

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Deux nouvelles methodes de syntheses stereospecifiques de desoxy-2 c-glucosides possedant une fonction ester d'enol sont presentees : - l'addition conjuguee d'organocuprates cyanes sur des hexeno-1 pyrannuloses-3 peracetyles (l'anhydride acetique piegeant l'enolate intermediaire) permet d'obtenir des aryl-alpha -d-c-glycosides. Cette methode est detendue avec succes en serie furannose; - l'arylation de glycals catalysee par des sels de palladium fournit les composes voulus en une seule etape a partir de derives glucidiques commerciaux. L'etude de la configuration des c-glycosides obtenus est effectuee et de nombreuses donnees structurales sont exposees

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Silva, Carlos Alberto Stechhahn da. "\"Efeito Aharonov-Bohm não-comutativo para partículas relativísticas de spin 1/2\"." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-02042007-125704/.

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Este trabalho destina-se ao estudo de modificações no espalhamento de Aharonov-Bohm para partículas relativísticas com spin 1/2, devido à não comutatividade do espaço, em 2+1 dimensões. As correções para o potencial de Aharonov-Bohm, sendo muito singulares, levam, em geral, ao aparecimento de divergências na expansão perturbativa em torno da teoria livre. Usando, então, como ponto de partida a solução exata da versão comutativa, determinamos, na aproximação de fluxo pequeno, a amplitude invariante, seção de choque diferencial e total, com as divergências eliminadas.
In this work we study modifications in the Aharonov-Bohm effect for relativistic spin 1/2 particles due the non-commutativity of space in 2+1 dimensions. The corrections for the Aharonov-Bohm potential originated from the non-commutativity of the underlying space are very singular, producing the appearance of divergences in the perturbative expansion around the free theory. Working with the pertubation around the exact solution of the commutative version of the problem, we determine then, in the small flux approximation, the invariant amplitude, and the corrections to the differential and total cross sections with all divergences eliminated.

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Wang, Xianyu, and Renu Malhotra. "Mean Motion Resonances at High Eccentricities: The 2:1 and the 3:2 Interior Resonances." IOP PUBLISHING LTD, 2017. http://hdl.handle.net/10150/624905.

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Mean motion resonances (MMRs) play an important role in the formation and evolution of planetary systems and have significantly influenced the orbital properties and distribution of planets and minor planets in the solar system and in. exoplanetary systems. Most previous theoretical analyses have focused on the low- to moderate-eccentricity regime, but with new discoveries of high-eccentricity resonant minor planets and even exoplanets, there is increasing motivation to examine MMRs in the high-eccentricity regime. Here we report on a study of the high-eccentricity regime of MMRs in the circular planar restricted three-body problem. Numerical analyses of the 2: 1 and the 3: 2 interior resonances are carried out for a wide range of planet-to-star mass ratio mu, and for a wide range of eccentricity of the test particle. The surface-of-section technique is used to study the phase space structure near resonances. We find that new stable libration zones appear at higher eccentricity at libration centers that are. shifted from those at low eccentricities. We provide physically intuitive explanations for these transitions in phase space, and we present novel results on the mass and eccentricity dependence of the resonance widths. Our results show that MMRs have sizable libration zones at high eccentricities, comparable to those at lower eccentricities.

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Brumfield, Brian. "Electronic to Vibrational Energy Transfer from Cl* (3 ²P_1/2) to N₂O(ν₁): Failure of a Simple Kinetic Mechanism." Wright State University / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=wright1133802860.

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Mousinho, Kristiana Cerqueira. "Estudo do Potencial AnticÃncer de um Derivado de Chalcona, 1-(4-Nitrofenil)-3-Fenilprop-2-En-1-Ona, In vitro e In vivo." Universidade Federal do CearÃ, 2010. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=10509.

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CoordenaÃÃo de AperfeiÃoamento de NÃvel Superior
A substÃncia 1-(4-Nitrofenil)-3-fenilprop-2-en-1-ona (CG) Ã um derivado de chalcona, sintetizado a partir da reaÃÃo quÃmica entre a acetofenona e para-nitro benzaldeÃdo. Para avaliar o seu potencial anticÃncer foi realizado um estudo farmacolÃgico de suas propriedades antitumorais em vÃrios modelos biolÃgicos in vitro e in vivo. A CG apresentou potente atividade citotÃxica nas 5 linhagens tumorais testadas, inibindo a proliferaÃÃo das cÃlulas tumorais pelo ensaio do MTT e em cÃlulas mononucleares do sangue perifÃrico (PMCB) humano atravÃs do ensaio do Alamar blue. Todas as linhagens mostraram sensibilidade ao tratamento com a CG, e a CI50 variou de 1,18ÂM em HCT-8 a 3,32ÂM em SF-295. O composto apresentou fraca citotoxicidade (CI50 igual a 7,07ÂM) nas cÃlulas PBMC, com exposiÃÃo a CG em 72h, em relaÃÃo Ãs cÃlulas de HL-60, utilizada como modelo nos demais testes biolÃgicos. O tempo de encubaÃÃo com o composto foi de 24h na maioria dos experimentos. Adicionalmente, a CG nÃo induziu efeitos hemolÃticos. O ensaio de exclusÃo por azul de Tripan revelou diminuiÃÃo da viabilidade celular principalmente apÃs 24h na maior concentraÃÃo testada (4ÂM) com 58,4%. Para os testes de atividade antiproliferativa, LA/BE mostrou em sua morfologia cÃlulas em apoptose nas duas maiores concentraÃÃes, enquanto que o BrdU, apresentou incorporaÃÃo do mesmo nas concentraÃÃes testadas. A morfologia analisada por May-Grunwald-Giemsa mostrou reduÃÃo do volume celular, condensaÃÃo da cromatina e fragmentaÃÃo nuclear. Adicionalmente, a CG induziu apoptose em cÃlulas leucÃmicas HL-60, com participaÃÃo das vias intrÃnseca e maior estÃmulo da via extrÃnseca, de maneira concentraÃÃo-dependente, como observado na integridade da membrana citoplasmÃtica, aumento da fragmentaÃÃo do DNA e externalizaÃÃo da fosfatidilserina. Na anÃlise do ciclo celular, foi observado parada na fase G2/M, sendo ativada as caspases 3, 7, 8 e 9 (a Ãltima na maior concentraÃÃo e confirmada pelo teste do Western blot). NÃo houve ativaÃÃo do Citocromo c. A CG nÃo foi capaz de induzir processos genotÃxicos/ mutagÃnicos (testes do cometa e micronÃcleo in vitro). No ensaio de atividade antitumoral in vivo, observou-se inibiÃÃo tumoral nas doses testadas (25 e 50mg/Kg/dia, via oral) de 54,85 e 69,11% respectivamente. As doses de CG causaram tumefaÃÃo celular e o surgimento de focos inflamatÃrios no parÃnquima ou estroma hepÃtico/renal, necrose nefrotÃxica focal, esteatose microvesicular, pigmentos de hemossiderina, hiperplasia das cÃlulas de Kupffer, congestÃo da polpa vermelha e desorganizaÃÃo dos folÃculos linfÃides esplÃnicos. AlÃm disso, os Ãndices bioquÃmicos mostraram aumento do AST e diminuiÃÃo da urÃia (CG 25mg/Kg/dia), diminuiÃÃo do ALT (5-FU e CG 25mg/Kg/dia); as alteraÃÃes hematolÃgicas mostraram leucopenia e plaquetopenia (5-FU), aumento dos leucÃcitos totais (CG 50mg/Kg/dia), aumento de neutrÃfilos e linfÃcitos em todos os grupos tratados. Todos os resultados nos levam a enfatizar que a CG possui grande potencialidade como molÃcula promissora por suas propriedades anticÃncer.
The substance 1- (4-Nitrofenil)-3- fenilprop-2- en-1-ona (CG) is a chalcone derivative, synthesized from a chemical reaction between acetophenone and p-nitro benzaldehyde. To evaluate its anticancer potential a pharmacological study of its antitumor properties in selected biological models in vitro e in vivo. CG presented a powerful cytotoxic activity in the 5 tested tumor lines evaluated, inhibiting cell proliferation of the tumor lines in the MTT assay and human peripheral mononuclear blood cells (PMBC) through the Alamar Blue assay. All cell lines showed sensitivity to the treatment with the CG, and the IC50 varied from 1,18 ÂM in HCT-8 to 3,32 ÂM in SF-295. The sample presented weak cytotoxic effect (IC50 of 7,07 ÂM) in cells PMBC, with 72h exposure to CG, compared to HL-60 cells (leukemic cell line), used in the next biological tests. The sample was incubated with the cells during 24h for the majority of the experiments. Additionally, CG did not induce hemolytic effects. The Tripan Blue assay showed a decrease of the cellular viability especially after 24h of incubation of the higher tested concentration (4 ÂM) with 58,4%. In assays for antiproliferative activity, OA/BE showed in its morphology cells going under apoptosis in the two higher concentrations, whereas the BrdU assay, presented incorporation of the same in the tested concentrations. The morphology analyzed with the May-Grunwald-Giemsa stain showed a decrease of the cellular volume, chromatin condensation and nuclear fragmentation.CG induced apoptosis in HL-60 cells, with participation of the intrinsic pathway and major stimulation of the extrinsic pathway, in a concentration-dependent manner, as observed in the cytoplasmatic membrane integrity, increase of DNA fragmentation and outsourcing of phosphatidylserine. In the cellular cycle analysis, it was observed a stop in the G2/M phase, activating caspases 3, 7, 8 and 9 (the last one in the highest concentration and confirmed by the Western blot assay). It was not observed activation of Cytochrome c. CG was not capable to induce mutagenic/genotoxic processes (comet assay and micronucleus in vitro). In the in vivo antitumor activity assay, tumor inhibition was observed in the tested doses (25 and 50mg/Kg/day, oral intake) of 54,85 and 69,11%, respectively . The doses of CG caused cellular swelling and the arise of inflammatory focus in the parenchyma or hepatic/renal stroma, focal nephrotoxic necrosis, microvesicular steatosis, hemosiderin pigments, hyperplasia of Kupffer cells, congestion of the red pulp and disorganization of the splenic lymphoid follicles. Furthermore, the biochemical indices had shown increase of AST and reduction of urea (25mg/Kg/day of CG), reduction of ALT (25mg/Kg/day of 5-FU and CG); hematologic alterations showed leukopenia and thrombocytopenia (5-FU), increase of total leukocytes (50mg/Kg/day of CG), increase of neutrophils and lymphocytes in all treated groups. All results led us to emphasize that CG possesses great potential as a promising molecule for its anticancer properties.

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Kong, Weixi. "Oxidative DNA Damage and DNA Binding Induced by 2, 2-Bis (Bromomethyl)-1, 3-Propanediol: Possible Mode of Action Implicated in its Carcinogenicity." Diss., The University of Arizona, 2012. http://hdl.handle.net/10150/223375.

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The studies in this dissertation research were conducted to investigate the possible mode of action by which a brominated flame retardant, 2, 2-Bis (bromomethyl)-1, 3-propanediol (BMP) causes genotoxicity. Binding of BMP to DNA and BMP induced DNA strand breaks were investigated in SV-40 immortalized human uroepithelial cells (UROtsa) as an in vitro model for the bladder (a tissue that developed cancer after two year exposure to BMP in rodents). Results showed binding of [¹⁴C]-BMP equivalents to DNA increased with increased exposure time and concentration of [¹⁴C]-BMP. Comet analysis indicated BMP significantly increased the extent of DNA strand breaks at 1 and 3 h of incubation. However, strand breaks were repaired by 6 h of incubation. The DNA damaging effects of BMP at 1 h was concentration dependent. Compared with the parent compound, BMP-glucuronide (the predominant metabolite of BMP) bound less to DNA and produced less DNA strand breaks in UROtsa cells. Evidences that the BMP induced strand breaks were the result of an oxidative stress include: a concentration and time dependent increase in ROS generation; increased expression of Nrf2 and HSP70; complete attenuation of BMP induced DNA strand breaks by the antioxidant, NAC; and the presence of the oxidized base 8-OHguanine. UROtsa cells appear to be target cells for BMP because, as compared to rat hepatocytes (non-target cells), these cells lack the ability to detoxify BMP via glucuronidation and also because they are deficient in glutathione, a major intracellular antioxidant molecule. Both of these genotoxic events, DNA binding and oxidative DNA damage may, in part, contribute to BMP carcinogenicity observed in rodents. The relevance of current results to humans is remained to be established.

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Barbosa, Marco Aurélio Alves. "Termodinâmica da água e dobramento de proteínas: estudo de modelos em rede." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-04032009-172802/.

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Neste trabalho realizamos dois estudos independentes sobre a termodinâmica de modelos de água e o dobramento de proteínas em rede.
On this work we develop two independent studies on lattice models for water thermodynamics and protein folding.

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Books on the topic "Mechanism of 2-methyl-1,3-dioxolane"

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Dankert, Helga. Technische Mechanik: Computerunterstützt mit 3 1/2-HD-Diskette. 2nd ed. Wiesbaden: Vieweg+Teubner Verlag, 1995.

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J, Jennings Terry. How do we know energy exists? Austin, Tex: Raintree Steck-Vaughn, 1995.

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Brackenridge, J. Bruce. The key to Newton's dynamics: The Kepler problem and the Principia : containing an English translation of sections 1, 2, and 3 of book one from the first (1687) edition of Newton's Mathematical principles of natural philosophy. Berkeley: University of California Press, 1995.

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Storey, Elsdon. The Expanded Polyglutamine Tract Spinocerebellar Ataxias. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780199937837.003.0013.

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The spinocerebellar ataxias are dominantly-inherited neurodegenerative disorders whose major clinical feature is incoordination. Although 32 have been described to date, those characterized by (CAG)n repeat expansions resulting in elongated polyglutamine tracts in their respective host proteins (SCAs 1, 2, 3, 6, 7, 17, and in part 8) are the most common and have been subject to the most detailed investigation of their pathogenic mechanisms. All are characterized by polyglutamine tract aggregates, toxicity of which was initially thought to be their pathogenic mechanism. However, recent research has emphasised the importance of host protein context, and the disease-specific mechanisms that this implies.

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Sousa, Ronald de. 3. Desire. Oxford University Press, 2015. http://dx.doi.org/10.1093/actrade/9780199663842.003.0003.

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Love essentially involves desire. But what is desire? And what sorts of desire are characteristic of love? ‘Desire’ explains that some of the things lovers want are features desirable in any friendly relationship: trust, intimacy, emotional resonance, companionship, concern for one another’s welfare. Erotic love adds more specific desires. The full cycle of desire and pleasure has five stages: (1) desire motivates us to pursue a goal; (2) pursuit secures the object of desire; (3) the object of desire causes pleasure; (4) pleasure triggers the reward mechanism; and (5) that mechanism reinforces the desire. The curse of satisfaction, the altruists’ dilemma, and two types of desire—reason-based and reason-free desire—are also considered.

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Tipler, Paul Allen. Physics Vol 1 & Vol 2 & Student Solutions Manual Vol 1 & Vol 2 and 3: Vol. 1: Mechanics, Oscillations and Waves, Thermodynamics. W. H. Freeman, 2002.

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Tipler, Paul Allen. Physics Volume 1 & Volume 2 & Volume 3 & E-Study Book: Vol. 1: Mechanics, Oscillations and Waves, Thermodynamics. W. H. Freeman, 2000.

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Glassy Materials And Disordered Solids An Introduction To Their Statistical Mechanics. World Scientific Publishing Company, 2011.

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PUBLISHER, PRENTICE HALL. Bedford and Fowler Engineering Mechanics: 1. Statics, 2. Dynamics, and 3. Statics and Dynamics. Pearson Education, Limited, 2004.

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Tipler, Paul Allen. Physics Volume 1 & Physics Volume 2 & Physics Volume 3 & Solutions Manual: Vol. 1: Mechanics, Oscillations and Waves, Thermodynamics. W. H. Freeman, 1999.

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Book chapters on the topic "Mechanism of 2-methyl-1,3-dioxolane"

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Ramsay, Rona R., Steven C. Koerber, and Thomas P. Singer. "Stopped-flow studies on the mechanism of the oxidation of N—methyl - 4 - phenyl - 1 , 2 , 3 , 6 - tetrahydropyridine (HPTP) by monoamine oxidase." In Flavins and Flavoproteins 1987, edited by D. E. Edmondson and D. B. McCormick, 705–8. Berlin, Boston: De Gruyter, 1987. http://dx.doi.org/10.1515/9783110884715-118.

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Kittel, Charles, Walter D. Knight, Malvin A. Ruderman, A. Carl Helmholz, and Burton J. Moyer. "(1/r 2)-Kraftgesetz." In Mechanik, 165–82. Berlin, Heidelberg: Springer Berlin Heidelberg, 1991. http://dx.doi.org/10.1007/978-3-642-58195-3_9.

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Deych, Lev I. "Spin 1/2." In Advanced Undergraduate Quantum Mechanics, 273–327. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-71550-6_9.

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Basdevant, Jean-Louis. "Spin 1/2." In Lectures on Quantum Mechanics, 279–311. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-43479-7_12.

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Negishi, Tomoe, Sakae Arimoto, Chiharu Nishizaki, and Hikoya Hayatsu. "Inhibition of the Genotoxicity of 3-Amino-1-Methyl-5H- Pyrido[4,3-b]Indole (Trp-P-2) in Drosophila by Chlorophyll." In Antimutagenesis and Anticarcinogenesis Mechanisms II, 341–44. Boston, MA: Springer US, 1990. http://dx.doi.org/10.1007/978-1-4615-9561-8_29.

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Gallego, Mar Gómez, and Miguel A. Sierra. "Level 1 — Case 2 Sulfenylation of Indole." In Organic Reaction Mechanisms, 7–12. Berlin, Heidelberg: Springer Berlin Heidelberg, 2004. http://dx.doi.org/10.1007/978-3-642-18788-9_2.

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Merlet, Jean-Pierre. "Efficient Kinematics of a 2-1 and 3-1 CDPR with Non-elastic Sagging Cables." In Mechanisms and Machine Science, 3–12. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-75789-2_1.

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Leydesdorff, Loet. "Knowledge-Based Innovations and Social Coordination." In Qualitative and Quantitative Analysis of Scientific and Scholarly Communication, 1–35. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-59951-5_1.

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AbstractThree themes have been central to my research program: (1) the dynamics of science, tech-nology, and innovation; (2) the scientometric operationalization and measurement of these dynamics; and (3) the Triple Helix (TH) of university-industry-government relations. In this introductory chapter, I relate these three themes first from an autobiographical perspective to (i)) Luhmann’s sociological theory about meaning-processing in communications with (ii) information-theoretical operationalizations of the possible synergies in Triple-Helix relations, and with (iii) anticipation as a selection mechanism in cultural evolutions different from “natural selection.” Interacting selection mechanisms can drive the development of redundancy; that is, options that are available, but have not yet been used. An increasing number of options is crucial for the viability of innovation systems more than is past performance. A calculus of redundancy different from and complementary to information calculus is envisaged.

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Gallego, Mar Gómez, and Miguel A. Sierra. "Level 1 — Case 15 Oxazoline N-Oxides as Dipoles in [3+2] Cycloadditions." In Organic Reaction Mechanisms, 101–6. Berlin, Heidelberg: Springer Berlin Heidelberg, 2004. http://dx.doi.org/10.1007/978-3-642-18788-9_15.

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Ynduráin, Francisco J. "Spin 1/2 Particles." In Relativistic Quantum Mechanics and Introduction to Field Theory, 35–66. Berlin, Heidelberg: Springer Berlin Heidelberg, 1996. http://dx.doi.org/10.1007/978-3-642-61057-8_3.

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Conference papers on the topic "Mechanism of 2-methyl-1,3-dioxolane"

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Som, S., Z. Wang, W. Liu, and D. E. Longman. "Comparison of Different Chemical Kinetic Models for Biodiesel Combustion." In ASME 2013 Internal Combustion Engine Division Fall Technical Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/icef2013-19094.

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The current study compares the predictions by four different published mechanisms in literature which have been used for 3 dimensional compression ignition engine simulations. These four mechanisms use two different sets of surrogates: (a) methyl decanoate, methyl 9-decenoate, and n-heptane, (b) methyl butanoate and n-heptane. The mechanisms include: (1) 115 species and 460 reactions [1] using surrogate mixture (a); (2) 77 species and 209 reactions [2] using surrogate mixture (a); (3) 145 species and 869 reactions [3] using surrogate mixture (b); (4) 41 species and 150 reactions [4] using surrogate mixture (b). The different reduction techniques implemented to obtain the reduced mechanisms from the detailed mechanisms are briefly described. The surrogate mixture compositions are then modified to match the cetane number of the real biodiesel fuels. The experimental data for comparison include jet-stirred reactor data for species concentrations for biodiesel derived from rapeseed oil and 3 dimensional constant volume combustion data (for ignition, combustion, and emission characteristics), engine data (for pressure, heat release rate, and emission characteristics) for soy-derived biodiesel. 0-D and 3-D constant volume simulations with all the mechanisms can capture the general experimental trends quite well. Large surrogate models and mechanisms tend to provide better predictions at the expense of increased computational costs. The 115 species and 460 reaction mechanism was observed to perform the best among the mechanisms in predicting the jet-stirred reactor and 3-D constant volume data. It was observed that all the mechanisms are able to qualitatively capture the engine performance and emission characteristics.

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Li, Gang, Gang Liu, and Dao-Bin Zhang. "SYNTHESIS, PHOTOCHROMISM PROPERTIES OF 1-(2-METHYL-1-THIENYL)-2-[2-METHYL-5-(1,3-DIOXOLANE)-3-THIENYL] PERFLUOROCYCLOPENTENE." In 2015 International Conference on Material Engineering and Mechanical Engineering (MEME2015). WORLD SCIENTIFIC, 2016. http://dx.doi.org/10.1142/9789814759687_0166.

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Yang, Junfeng, Monica Johansson, and Valeri Golovitchev. "Engine Performance and Emissions Formation for RME and Conventional Diesel Oil: A Comparative Study." In ASME 2009 Internal Combustion Engine Division Spring Technical Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/ices2009-76121.

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A comparative study on engine performance and emissions (NOx, soot) formation has been carried out for the Volvo D12C diesel engine fueled by Rapeseed Methyl Ester, RME and conventional diesel oil. The combustion models, used in this paper, are the modifications of those described in [1–2]. After the compilation of liquid properties of RME specified as methyl oleate, C19H36O2, making up 60% of RME. The oxidation mechanism has been compiled based on methyl butanoate ester, mb, C5H10O2 oxidation model [3] supplemented by the sub-mechanisms for two proposed fuel constituent components, methyl decanoate, md, C11H22O2, n-heptane, C7H16, and soot and NOx formations reduced and “tuned” by using the sensitivity analysis. A special global reaction was introduced to “crack” the main fuel into constituent components, md, mb and propyne, C3H4, to reproduce accurately the proposed RME chemical formula. The sub-mechanisms were collected in the general one consisting of 99 species participating in 411 reactions. The combustion mechanism was validated using shock-tube ignition-delay data at diesel engine conditions and flame propagation speeds at atmospheric conditions. The engine simulations were carried out for Volvo D12C engine fueled both RME and conventional diesel oil. The numerical results illustrate that in the case of RME, nearly 100% combustion efficiency was predicted when the cumulative heat release, was compared with the RME LHV, 37.2 kJ/g.. To minimize NOx emissions, the effects of 20–30% EGR levels depending on the engine loads and different injection strategies were analyses. To confirm the optimal engine operation conditions, a special technique based on the time-transient parametric φ-T maps [4] has been used.

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Fu, Y. L., D. D. Xue, C. B. Fan, and S. Z. Pu. "Synthesis and Application of 1-(3, 5-dimethyl-4-isoxazolyl)-2-{2-methyl-5-[4-(1,3-dioxolane)-phenyl] -3-thienyl} Perfluorocyclopentene." In International Conference on Materials Chemistry and Environmental Protection 2015. Paris, France: Atlantis Press, 2016. http://dx.doi.org/10.2991/meep-15.2016.22.

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Suttie, W. J., A. Cheung, and M. G. Wood. "ENZYMOLOGY OF THE VITAMIN K-DEPENDENT CARBOXYLASE: CURRENT STATUS." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643991.

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The vitamin K-dependent microsomal carboxylase converts glutamyl residues in precursor proteins to γ-carboxyglutamyl (Gla) residues in completed proteins. The enzyme activity is present in significant activities in most non-skeletal tissues but has been studied most extensively in rat and bovine liver. Early studies of the enzyme utilized bound precursors of vitamin K-dependent clotting factors as substrates for the enzyme and demonstrated that the enzyme requires the reduced form of vitamin K (vitamin KH2), O2, and CO2. Subsequent investigations have taken advantage of the observation that the enzyme will carboxylate low-molecular-weight peptide substrates with Glu-Glu sequences. Utilizing a substrate such as Phe-Leu-Glu-Glu-Leu, it has been possible to demonstrate that γ-C-H release from the Glu residue of a substrate is independent of CO2 concentration. The formation of vitamin K 2,3-epoxide can also be demonstrated in a crude microsomal system, and it can be shown that the formation of this metabolite can be stimulated by the presence of a peptide substrate of the carboxylase. These observations have led to the general hypothesis that the mechanism of action of the enzyme involves interaction of vitamin KH2 with O2 to form an oxygenated intermediate that can interact with a substrate Glu residue to abstract a γ-hydrogen and in the process he converted to vitamin K epoxide (KO). The current evidence suggests that, either directly or indirectly, removal of the γ-C-H results in the formation of a carbanion at the γ-position of the Glu residue which can interact with CO2 to form Gla. The Glu residue intermediate which is formed can be demonstrated to partition between accepting a proton in the media to reform Glu, or interacting with CO2 to form Gla. Current data do not distinguish between the direct formation of a carbanion coupled to proton removal, or the participation of a reduced intermediate. Recent studies have demonstrated that the enzyme will carry out a partial reaction, the formation of vitamin K epoxide, at a decreased rate in the absence of a Glu site substrate. Epoxide formation under these conditions has the same for O2 as the carboxylation reaction and is inhibited in the same manner as the carboxylation reaction. In the presence of saturating concentrations of a Glu site substrate and C02, the ratio of KO formed, γ-C-H released, and C02 formed is 1:1:1. However, KO formation can be uncoupled from and proceeds at a higher rate than γ-C-H bond cleavage and Gla formation at low Glu site substrate concentrations. At saturating concentrations of CO2, Gla formation is equivalent to γ-C-H bond cleavage, and this unity is not altered by variations in vitamin KH2 or peptide substrate concentrations. Natural compounds with vitamin K activity are 2-Me-l,4-naphthoquinones with a polyprenyl side chain at the 3-position. Studies of vitamin K analogs have demonstrated that a 2-Me group is essential for activity but that the group at the 3-position can vary significantly. Modification of the aromatic ring of the naphthoquinone nucleus by methyl group substitution can result in alterations of either the rate of the carboxylation reaction or the apparent affinity of the enzyme for the vitamin. Studies of a large number of peptide substrates have failed to reveal any unique primary amino acid sequence which is a signal for carboxylation. However, current evidence from a number of sources suggests that a basic amino acid rich "propeptide" region of the intracellular form of the vitamin K-dependent proteins is an essential recognition site for the enzyme. This region of the precursor is lost in subsequent processing, and the manner in which it directs this posttranslational event is not yet clarified. Supported by NIH grant AM-14881.

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Kong, Xianwen, and Andreas Müller. "A Single-Loop 7R Spatial Mechanism That Has Three Motion Modes With the Same Instantaneous DOF but Different Finite DOF." In ASME 2018 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/detc2018-85125.

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Multi-mode mechanisms, including kinematotropic mechanisms, are a class of reconfigurable mechanisms that can switch motion modes with the same or different DOF (degree-of-freedom). For most of the multi-mode mechanisms reported in the literature, the instantaneous (or differential) DOF and finite DOF in a motion mode are equal. In this paper, we will discuss the construction, reconfiguration analysis, and higher-order mobility analysis of a multi-mode single-loop 7R mechanism that has three motion modes with the same instantaneous DOF but different finite DOF. Firstly, the novel multi-mode single-loop 7R spatial mechanism is constructed by inserting one revolute (R) joint into a plane symmetric Bennett joint-based 6R mechanism for circular translation. The reconfiguration analysis is then carried out in the configuration space by solving a set of kinematic loop equations based on dual quaternions and the natural exponential function substitution using tools from algebraic geometry. The analysis shows that the multi-mode single-loop 7R spatial mechanism has three motion modes, including a 2-DOF planar 5R mode and two 1-DOF spatial 6R modes and can transit between each pair of motion modes through two transition configurations. The higher-order mobility analysis shows that the 7R mechanism has two-instantaneous DOF at a regular configuration of any motion mode and three instantaneous DOF in a transition configuration. The infinitesimal motions that are not tangential to finite motions are of second-order in transition configurations between 2-DOF motion mode 1 and 1-DOF motion modes 2 or 3 or first-order in transition configurations between 1-DOF motion modes 2 and 3.

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Miyazaki, Katsumasa, Kunio Hasegawa, Naoki Miura, Koichi Kashima, and Douglas A. Scarth. "Technical Basis of Proposed New Acceptance Standards for Class 1, 2 and 3 Piping." In ASME 2007 Pressure Vessels and Piping Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/pvp2007-26124.

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Acceptance Standards in Section XI of the ASME Boiler and Pressure Vessel Code have an important role as the first step in the flaw evaluation procedure. When a flaw size is within the allowable flaw size in the Acceptance Standard, the flaw is acceptable and analytical evaluation is not required. Although ASME Section XI has Acceptance Standards for Class 1 piping in IWB-3500, there are no Acceptance Standards for Class 2 and 3 piping. Furthermore, the development of the current Acceptance Standards for Class 1 piping was based on flaw detectability by ultrasonic inspection and consideration of fracture mechanics. In this paper, the development of proposed new Acceptance Standards for Class 2 and 3 piping, as well as for Class 1 piping, is described. The development methodology is based on a fracture mechanics approach. For Class 1 piping with high fracture toughness, the allowable flaw sizes were determined by limit load solution. For Class 1 piping, the intent was to maintain overall consistency with the current Acceptance Standards. Proposed Acceptance Standards for Class 2 and 3 austenitic piping were also developed by the methodology used to develop the proposed new Acceptance Standards for Class 1 piping. Allowable flaw sizes for both surface flaws and subsurface flaws for preservice and inservice examinations were developed.

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Tapang. "An alternative matching mechanism: getting rid of attentional gain control and its consequent 2/3 rule in ART-1." In International Joint Conference on Neural Networks. IEEE, 1989. http://dx.doi.org/10.1109/ijcnn.1989.118399.

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He, Chuan-Hua, Chun Geun Lee, Charles Dela Cruz, Wei Liu, Farida Ahangari, and Jack A. Elias. "Chitinase 3-Like-1 (Chi3l1) Stimulates The Wnt/²-Catenin Pathway Via An IL-13 Receptor Alpha 2 Dependent Mechanism." In American Thoracic Society 2012 International Conference, May 18-23, 2012 • San Francisco, California. American Thoracic Society, 2012. http://dx.doi.org/10.1164/ajrccm-conference.2012.185.1_meetingabstracts.a5524.

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Sirimamilla, P. Abhiram, Jevan Furmanski, and Clare M. Rimnac. "Effect of Non-Uniform Material De-Cohesion on Crack Initiation From Notches in Crosslinked UHMWPE." In ASME 2011 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2011. http://dx.doi.org/10.1115/sbc2011-54012.

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Ultra High Molecular Weight Polyethylene (UHMWPE) has been successfully used as a bearing material in total joint arthroplasty for the last 4 decades [1] but about 5%–10% of the implants undergo revision surgery in the first 10 years of implantation [2]. Crack initiation from a stress-concentration design feature (e.g., a sharp corner of a locking mechanism on an acetabular component) has been observed to lead to catastrophic failure in-vivo [3]. Therefore, it is important to understand crack initiation from clinically relevant notches to mitigate the risk of component fracture. UHMWPE is a semi-crystalline polymer and little is known about the physical mechanisms governing crack tip phenomena. The time dependent theoretical expression of fracture mechanics indicates that the critical fracture energy (Jc) varies with crack initiation time (ti) with an exponent ‘n’ (Equation 1).

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Reports on the topic "Mechanism of 2-methyl-1,3-dioxolane"

1

Kim, G. M., and G. H. Meier. Breakdown mechanisms of Al/sub 2/O/sub 3/, Cr/sub 2/O/sub 3/ and SiO/sub 2/ scales in H/sub 2//H/sub 2/O/H/sub 2/S environments: Final report, Volume 1. Office of Scientific and Technical Information (OSTI), January 1989. http://dx.doi.org/10.2172/5976591.

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Lavadenz, Magaly, and Gisela O’Brien. District Administrators' Perspectives on the Impact of The Local Control Funding Formula on English Learners. Loyola Marymount University, 2017. http://dx.doi.org/10.15365/ceel.policy.6.

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Two years into implementation, this policy brief examines how California’s Local Control Funding Formula (LCFF) and its accompanying Local Control Accountability Plan (LCAP) meet the needs of English Learners (ELs). Researchers seek to understand district administrator perspectives on the impact of LCFF for ELs through interviews and focus groups with administrators that represent districts from Northern, Central, and Southern California. Findings reveal that although the LCAP serves as a mechanism to increase personnel and PD efforts to address EL needs, it is still largely viewed as a compliance document that requires alignment with other strategic documents and is sensitive to changes in leadership. The following policy recommendations are made as a result of these findings: 1) re-design the LCAP to support districts in specifying EL learning goals, services, assessments and expected outcomes; 2) differentiate support for district administrators; and 3) invest (long-term) in district-level and site-level professional development with a focus on EL success.

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Thompson, John, Thompson, John, Njuguna Ndung’u, Miguel Albacete, Abid Q. Suleri, Junaid Zahid, and Rubab Aftab. The Impact of Covid-19 on Livelihoods and Food Security. Institute of Development Studies (IDS), June 2021. http://dx.doi.org/10.19088/core.2021.002.

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Studies of livelihoods and food systems since the start of the global pandemic in 2020 have shown a consistent pattern: the primary risks to food and livelihood security are at the household level. Covid-19 is having a major impact on households’ production and access to quality, nutritious food, due to losses of income, combined with increasing food prices, and restrictions to movements of people, inputs and products. The studies included in this Research for Policy and Practice Report and supported by the Covid-19 Responses for Equity (CORE) Programme span several continents and are coordinated by leading research organisations with a detailed understanding of local food system dynamics and associated equity and livelihood issues in their regions: (1) the impact of the Covid-19 pandemic on livelihoods in sub-Saharan Africa; (2) supporting small and medium enterprises, food security, and evolving social protection mechanisms to deal with Covid-19 in Pakistan; and (3) impact of Covid-19 on family farming and food security in Latin America: evidence-based public policy responses.

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Thompson, John, Thompson, John, Njuguna Ndung’u, Miguel Albacete, Abid Q. Suleri, Junaid Zahid, and Rubab Aftab. The Impact of Covid-19 on Livelihoods and Food Security. Institute of Development Studies (IDS), June 2021. http://dx.doi.org/10.19088/core.2021.001.

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Studies of livelihoods and food systems since the start of the global pandemic in 2020 have shown a consistent pattern: the primary risks to food and livelihood security are at the household level. Covid-19 is having a major impact on households’ production and access to quality, nutritious food, due to losses of income, combined with increasing food prices, and restrictions to movements of people, inputs and products. The studies included in this Research for Policy and Practice Report and supported by the Covid-19 Responses for Equity (CORE) Programme span several continents and are coordinated by leading research organisations with a detailed understanding of local food system dynamics and associated equity and livelihood issues in their regions: (1) the impact of the Covid-19 pandemic on livelihoods in sub-Saharan Africa; (2) supporting small and medium enterprises, food security, and evolving social protection mechanisms to deal with Covid-19 in Pakistan; and (3) impact of Covid-19 on family farming and food security in Latin America: evidence-based public policy responses.

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