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La población actual del departamento del Cauca es el resultado de la mezcla de tres poblaciones parentales (europea, amerindia y africana). En este estudio se determinó la composición genética de 306 residentes del departamento mediante... more
La población actual del departamento del Cauca es el resultado de la mezcla de tres poblaciones parentales (europea, amerindia y africana). En este estudio se determinó la composición genética de 306 residentes del departamento mediante la utilización de 34 variantes autosómicas, 9 variantes en el cromosoma X, 6 en el ADNmt y 8 en el cromosoma Y. Los análisis de las variantes autosómicas y del cromosoma X revelaron que la población europea y la amerindia han contribuido en mayor proporción al actual acervo genético de la población estudiada. Los resultados de las variantes en el ADNmt y del cromosoma Y sugieren un fuerte sesgo sexual (flujo génico asimétrico) en el proceso de mezcla, en el que los cruces interétnicos fueron principalmente entre los colonizadores europeos y las mujeres nativas.
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Neospora caninum causes reproductive disorders in dairy cattle such as repeat breeding, abortion, and anestrus, which are risk factors associated with the seroprevalence of N. caninum in Brazil and worldwide. This study aimed to verify... more
Neospora caninum causes reproductive disorders in dairy cattle such as repeat breeding, abortion, and anestrus, which are risk factors associated with the seroprevalence of N. caninum in Brazil and worldwide. This study aimed to verify the risk factors related to the seroprevalence of Neospora caninum in crossbred dairy cows in the city of Uberlândia, Minas Gerais. During, January to July 2013, 740 blood samples were collected from 57 herds with a history of reproductive disorders and determinations of antibody titers against N. caninum were obtained by ELISA assay. The seroprevalence of N. caninum was 18.4% (136/740). Risk factors for N. caninum were cows greater than 2 years of age (P = 0.034), mechanical milking (P = 0.012), and frequent purchase of animals (P = 0.004), in addition to individual history of abortion (P = 0.007) and repeat breeding (P = 0.030). The highest probability of occurrence of associated risk factors was associated with individual history of abortion and re...
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In this article, the evaluation of a structural model that seeks to identify predictors and mediators of posttraumatic growth (PTG) of people affected by a natural disaster is presented. The sample was composed of 349 adult men and women... more
In this article, the evaluation of a structural model that seeks to identify predictors and mediators of posttraumatic growth (PTG) of people affected by a natural disaster is presented. The sample was composed of 349 adult men and women who experienced the earthquake and tsunami on February 27, 2010 in Chile. A modeling with structural equations was used, contrasting two predictive models of PTG. The latent variables assessed were subjective severity, social sharing of emotion, intrusive rumination, deliberate rumination, problem-focused coping and posttraumatic growth. The best fit was obtained with the model that shows a direct influence of the subjective severity, problem-focused coping, and deliberate rumination in the presence of PTG. Problem-focused coping mediated the relation between subjective severity and social sharing with PTG. In turn, deliberate rumination mediated the relation of problem-focused coping and intrusive rumination with PTG. The results show the relevant ...
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The asymmetric unit of the title compound, C 10 H 16 N + 5 .Cl - , contains two molecules with quite different conformations of the biguanide moiety. The crystal structure determined by Herrnstadt et al. [J. Chem. Soc. Perkin Trans. 2... more
The asymmetric unit of the title compound, C 10 H 16 N + 5 .Cl - , contains two molecules with quite different conformations of the biguanide moiety. The crystal structure determined by Herrnstadt et al. [J. Chem. Soc. Perkin Trans. 2 (1979), pp. 735-740] is properly refined, the H-atom positions on the biguanide moiety are evident and the hydrogen-bonding scheme is clarified. Protonation of the biguanide moiety produces a rearrangement of protons in this part of the molecule. The two independent protonated molecules in the crystal form a hydrogen-bonded dimer through two intermolecular N-H...N hydrogen bonds. In addition, the molecules are held together by van der Waals forces and several N-H...Cl intermolecular interactions.
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M r = 248.3, orthorhombic, Pbcn, a = 35.934 (5), b = 7 . 5 0 2 (2), c = 10.056 (2)A, V = 2711(2) /~3, Z = 8 , D x = l . 2 2 M g m -3, CuKct, 2 = 1.5418/~, g = 0 . 6 9 7 m m -1, F ( 000 ) = 1056, T = 293 K, final R = 0.050 for 1600... more
M r = 248.3, orthorhombic, Pbcn, a = 35.934 (5), b = 7 . 5 0 2 (2), c = 10.056 (2)A, V = 2711(2) /~3, Z = 8 , D x = l . 2 2 M g m -3, CuKct, 2 = 1.5418/~, g = 0 . 6 9 7 m m -1, F ( 000 ) = 1056, T = 293 K, final R = 0.050 for 1600 observed reflections. The X-ray study confirms that in the solid state the structure of the Z isomer is similar to that inferred on the basis of chemical and spectroscopic evidence. In the crystal the title compound has a non-planar conformation and forms centrosymmetric hydrogen-bonded dimers, O. . .O distance 2.690 (3)A, O H . . . O angle 171 (2) °. There is no conjugation between the phenyl ring and the C(3) double bond. Introduction. As a part of our studies regarding the total synthesis of compounds with anticonvulsant activity, we became interested in designing a synthetic entry into the ),-hydroxy, ?-phenyl caproamide (Carvajal, Russek, Tapia & Massieu, 1964; P6rez de la Mora & Tapia, 1973; Joseph-Nathan, Massieu, Carvajal & Tapia, 1978), molecule (I). Careful analysis of the structural features characteristic of this anticonvulsant molecule suggests the utilization of (II) as a versatile intermediate for this synthesis. The (E and Z) geometric isomers of (II) were obtained from the condensation of acetophenone with diethyl succinate at alkaline pH * Contribution No. 669 of the Instituto de Quimica, UNAM. t To whom correspondence should be addressed. (Stobbe, 1899). Both isomers (IIa, IIb) were characterized on the basis of chemical and spectroscopic methods (Garcia, 1983).
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Different approaches have been followed to model the hydraulic transport of particles, ranging from pure empirical correlations to general models based on fundamental principles. However, these models suffer from uncertainties associated... more
Different approaches have been followed to model the hydraulic transport of particles, ranging from pure empirical correlations to general models based on fundamental principles. However, these models suffer from uncertainties associated with the parameters in the constitutive equations and scarcity of experimental data in the literature. Nonintrusive techniques such as electric impedance tomography (EIT) can be used to circumvent the
Research Interests: Engineering, Mechanical Engineering, Chemical Engineering, Mechanics, Two Phase Flow, and 11 moreFinite element method, Tomography, Electrical Impedance Tomography, Ranging, Sampling Technique, Experimental Data, Electric Field, Constitutive Equation, Data Acquisition System, Generic model, and Electrical Impedance
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An open-ended capillary cell has been developed to measure thermodynamic diffusion coefficients of electrolytes, in aqueous solution, in swelled polymeric membranes. Also a new method to determine the integral diffusion coefficient of... more
An open-ended capillary cell has been developed to measure thermodynamic diffusion coefficients of electrolytes, in aqueous solution, in swelled polymeric membranes. Also a new method to determine the integral diffusion coefficient of water in membranes is presented. In this work we present a description of the methods as well as the experimental results of the diffusion coefficients of potassium chloride
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ABSTRACT The reaction of [{P(μ-NtBu)}2(μ-NH)}5I]−[Li(thf)4]+([1·I]−[Li(thf)4]+) with NaOMe in CH2Cl2 gives the title compound [{P(μ-NtBu)}2(μ-NH)]5(CH2Cl2)2 [1·(CH2Cl2)2] the first adduct containing this type of macrocyclic... more
ABSTRACT The reaction of [{P(μ-NtBu)}2(μ-NH)}5I]−[Li(thf)4]+([1·I]−[Li(thf)4]+) with NaOMe in CH2Cl2 gives the title compound [{P(μ-NtBu)}2(μ-NH)]5(CH2Cl2)2 [1·(CH2Cl2)2] the first adduct containing this type of macrocyclic phosph(III)azane host and a neutral guest.
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... Felipe García 1 ,; Mary McPartlin 1 ,; James V. Morey 1 ,; Daisuke Nobuto 2 ,; Yoshinori Kondo 3 ,; Hiroshi Naka 3 ,; Masanobu Uchiyama 4,5 ... 3 PC Andrikopoulos , DR Armstrong , HRL Barley , W. Clegg , SH Dale , E. Hevia , GW... more
... Felipe García 1 ,; Mary McPartlin 1 ,; James V. Morey 1 ,; Daisuke Nobuto 2 ,; Yoshinori Kondo 3 ,; Hiroshi Naka 3 ,; Masanobu Uchiyama 4,5 ... 3 PC Andrikopoulos , DR Armstrong , HRL Barley , W. Clegg , SH Dale , E. Hevia , GW Honeyman , AR Kennedy , RE Mulvey , J. Am. ...
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Research Interests: Geography, Human Geography, Environmental Science, NO, PM, and 5 moreSo, Co, Atmospheric pollution, Ozone, and Air Quality Index
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... Alan Bashalla, Felipe Garcíab, Alexander A. Hopkinsb, Jody A. Woodb, Mary McPartlina, Anthony D. Woods*b and Dominic S. Wright*b. a School of Chemistry, University of North London, London, UK N7 8DB. ... 11, M. Baudler, G.... more
... Alan Bashalla, Felipe Garcíab, Alexander A. Hopkinsb, Jody A. Woodb, Mary McPartlina, Anthony D. Woods*b and Dominic S. Wright*b. a School of Chemistry, University of North London, London, UK N7 8DB. ... 11, M. Baudler, G. Reuschenbach, J. Hellmann and J. Hahn, Z. Anorg ...
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The reaction of [ClP(mu-NtBu)]2 (1) with H2O (1 : 2 equivalents) in the presence of excess Et3N gives the new chain compound [(mu-O)[P(mu-NtBu)2P(H)=O]2] (3), consisting of two P2N2 rings linked by a mu-O atom and terminating in P(V)(H)=O... more
The reaction of [ClP(mu-NtBu)]2 (1) with H2O (1 : 2 equivalents) in the presence of excess Et3N gives the new chain compound [(mu-O)[P(mu-NtBu)2P(H)=O]2] (3), consisting of two P2N2 rings linked by a mu-O atom and terminating in P(V)(H)=O groups. A similar chain species is obtained from the reaction of the lithiate of [(tBuNH)P(mu-NtBu)2P(H)=O] (5) with [ClP(mu-NtBu)2P(NHtBu)] (2), the product being [(mu-O)[P(mu-NtBu)2P(NHtBu)]2] (6). Compounds 3 and 6 are the first examples of O-bridged chain phosphazanes and potential precursors to new phosphorus-nitrogen macrocycles. The syntheses and X-ray structures of 3, 5 and 6 are reported.
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The reaction of 1,2-(NH(2))(2)C(6)H(4) with Sb(NMe(2))(3)/(n)BuLi gives the formally-aromatic heterocyclic anion [C(6)H(4)N(2)Sb](-) which oligomerises into a cyclic tetrameric arrangement in the complex [C(6)H(4)N(2)SbLi.PMDETA](4) ()... more
The reaction of 1,2-(NH(2))(2)C(6)H(4) with Sb(NMe(2))(3)/(n)BuLi gives the formally-aromatic heterocyclic anion [C(6)H(4)N(2)Sb](-) which oligomerises into a cyclic tetrameric arrangement in the complex [C(6)H(4)N(2)SbLi.PMDETA](4) () (PMDETA = {Me(2)NCH(2)CH(2)}(2)NMe) using a donor-acceptor bonding mode that is unique in related main group heterocyclic anions.
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The 1 : 1 reactions of [ClP(mu-NtBu)]2 with the difunctional aromatic amines 1,2-1-YH-2-NH2-C6H4 in the presence of Et3N give the dimeric phosph(III)azane macrocycles [{P(mu-NtBu)2(1-Y-2-HN-C6H4)]2, predominantly as the cis isomer in the... more
The 1 : 1 reactions of [ClP(mu-NtBu)]2 with the difunctional aromatic amines 1,2-1-YH-2-NH2-C6H4 in the presence of Et3N give the dimeric phosph(III)azane macrocycles [{P(mu-NtBu)2(1-Y-2-HN-C6H4)]2, predominantly as the cis isomer in the case of Y=O (1.cis) and as the trans isomer for Y=S (2.trans). Model M.O. calculations suggest that the selection of the cis and trans isomers is not thermodynamically controlled. The alternative isomers 1.trans and 2.cis are generated exclusively by the deprotonation of the model intermediates [(1-Y-2-NH2-C6H4)P(mu-NtBu)]2[Y=O (3), S (4)] with nBuLi followed by cyclisation with [ClP(mu-NtBu)]2. The solid-state structures of 1.cis/trans(50 : 50), 2.cis, 3 and 4 are reported.
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The condensation reactions of the dimer [ClP(micro-NR)](2) with organic diacids [LL(H)(2)], possessing linear orientations of their organic groups, result in the formation of phospha(III)zane macrocyles of the type [{P(mu-NR)}(2)(LL)](n)... more
The condensation reactions of the dimer [ClP(micro-NR)](2) with organic diacids [LL(H)(2)], possessing linear orientations of their organic groups, result in the formation of phospha(III)zane macrocyles of the type [{P(mu-NR)}(2)(LL)](n) of various sizes. The series of macrocycles [{P(mu-N(t)Bu)}(2){1,5-(NH)(2)C(10)H(6)}](3), [{P(mu-NCy)}(2)(1,5-O(2)C(10)H(6))](n) [n = 3; n = 4], [{P(mu-N(t)Bu)}(2){1,4-(NH)(2)C(6)H(4)}](4), [{P(mu-N(t)Bu)}(2)(1,4-O(2)C(6)H(4))], [{P(mu-NCy)}(2)(1,4-O(2)C(6)H(4))](3) and [{P(mu-N(t)Bu)}(2){(NH)C(6)H(4)OC(6)H(4)(NH)}](2) can be related to classical organic frameworks, like calixarenes.
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Research Interests: Chemistry, Crystallography, Halide, Medicine, CHEMICAL SCIENCES, and 4 moreIon, Dimer, Selectivity, and Tetramer
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The two products obtained from the reaction of 1,2-(PH(2))(2)C(6)H(4) with the mixed-metal base (n)BuLi-Sb(NMe(2))(3) in the presence of 12-crown-4, [Li(12-crown-4)(2)]+[C(6)H(4)P(3)]- (1) and {[Li(12-crown-4)(2)]+}3[Sb(11)]3- (2),... more
The two products obtained from the reaction of 1,2-(PH(2))(2)C(6)H(4) with the mixed-metal base (n)BuLi-Sb(NMe(2))(3) in the presence of 12-crown-4, [Li(12-crown-4)(2)]+[C(6)H(4)P(3)]- (1) and {[Li(12-crown-4)(2)]+}3[Sb(11)]3- (2), represent thermodynamic sinks in which P-P and Sb-Sb bonding are maximized at the expense of P-Sb bonding, providing access to the 1,2,3-[C(6)H(4)P(3)]- phospholide anion.
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The hydrolysis of [ClP(mu-NtBu)]2 with H2O-Et3N in thf, followed by in situ lithiation with nBuLi gives the Li13 cage [[[O-P(mu-NtBu)]2Li2]3(LiCl)6Li(Cl/OnBu)0.5(thf)7], containing a [O-P(mu-NtBu)]2(2-) dianion that is isoelectronic with... more
The hydrolysis of [ClP(mu-NtBu)]2 with H2O-Et3N in thf, followed by in situ lithiation with nBuLi gives the Li13 cage [[[O-P(mu-NtBu)]2Li2]3(LiCl)6Li(Cl/OnBu)0.5(thf)7], containing a [O-P(mu-NtBu)]2(2-) dianion that is isoelectronic with ligands of the type [(RN)P(mu-NR)]2(2-).
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The heterometallic Sb(III)/Li cage complex [{Sb(P-t-Bu)3}2Li6·6THF] (1) is obtained by the low-temperature (<0°C) reaction of Sb(NMe2)3 with t-BuPHLi (1:3 equiv) in THF. Thermolysis of this reaction solution leads to the formation of... more
The heterometallic Sb(III)/Li cage complex [{Sb(P-t-Bu)3}2Li6·6THF] (1) is obtained by the low-temperature (<0°C) reaction of Sb(NMe2)3 with t-BuPHLi (1:3 equiv) in THF. Thermolysis of this reaction solution leads to the formation of the bicyclic distibane [(t-BuP)3Sb]2 (2). 31P NMR spectroscopic studies reveal that this process involves initial formation of [(t-BuP)3Sb] and [t-Bu(H)PP-t-Bu] anions. Complexes 1 and 2 have been characterized in the solid state by X-ray diffraction studies.Key words: antimony, lithium, cage.
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The application of superbases, such as the well-known Schlosser base consisting of tBuOK and RLi, in the deprotonation of organic substrates is well established.1 Recently, Mulvey investigated the structural chemistry and applications of... more
The application of superbases, such as the well-known Schlosser base consisting of tBuOK and RLi, in the deprotonation of organic substrates is well established.1 Recently, Mulvey investigated the structural chemistry and applications of related mixed-metal amide reagents.2 These ...
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... 2 ,; Matthew L. Stead 1 ,; Robin S. Stein 1 ,; Dominic S. Wright Dr. 1. Article first published online: 3 AUG 2005. ... 1 R. Snaith, DS Wright in Lithium Chemistry: A Theoretical and Experimental Overview (Eds.: A.-M. Sapse, P. von R.... more
... 2 ,; Matthew L. Stead 1 ,; Robin S. Stein 1 ,; Dominic S. Wright Dr. 1. Article first published online: 3 AUG 2005. ... 1 R. Snaith, DS Wright in Lithium Chemistry: A Theoretical and Experimental Overview (Eds.: A.-M. Sapse, P. von R. Schleyer), Wiley, New York, 1994, chap. 8, p. 227. ...