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1.
Front Psychol ; 13: 949615, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36033058

RESUMO

Previous evidence has shown that excessive valuing happiness may relate to lower psychological wellbeing across cultures. Considering the lack of data with Spanish population, we examined the relation between tightly holding happiness emotion goals and subjective wellbeing in a sample of Spanish women, and explored the mediation role exerted by psychological inflexibility components (namely, cognitive fusion and experiential avoidance) in the relation between valuing happiness and subjective wellbeing. A female adult sample (n = 168) filled out measures of excessive valuing happiness, psychological inflexibility, positive affect, negative affect, and life satisfaction. Valuing happiness only showed positive total effects on negative affect and strong direct effects on both cognitive fusion and experiential avoidance. Analyses revealed the mediating roles exerted by psychological inflexibility components, with experiential avoidance leading to lower pleasure; and cognitive fusion leading to greater displeasure and lower life satisfaction. Psychological inflexibility components explained between 40 and 80% of the total effect of valuing happiness on our outcome variables. Our findings highlight the need for further research on the benefits of hedonic vs. values-based approaches to happiness.

2.
Chemistry ; 24(7): 1514-1517, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29271511

RESUMO

The mononuclear gold(II) halide complexes [AuCl3 ]- and [AuBr3 ]- are formed in the gas phase by collision-induced homolytic splitting of the only Au-C bond in the monoalkylgold(III) precursors [CF3 AuX3 ]- . The geometries of the whole series of [AuX3 ]- complexes (X=F, Cl, Br, I) have been calculated by DFT methods. It has also been found that the neutral AuX2 molecules behave as unsaturated species, showing significant affinity for an additional X- ligand. Moreover, in the open-shell [AuX3 ]- anions, homolytic splitting of one of the Au-X bonds and formation of the lower-valent [AuX2 ]- anions is favored over non-reducing halide dissociation. They should therefore be prone to disproportionation.

3.
Chemistry ; 23(28): 6919-6929, 2017 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-28317201

RESUMO

The homoleptic compound [PPh4 ][CF3 AuCF3 ] cleanly undergoes photoinduced oxidative addition of CF3 I to afford the organogold(III) derivative [PPh4 ][(CF3 )3 AuI] in good yield and under mild conditions. This compound provides a convenient entry to the chemistry of the perfluorinated (CF3 )3 Au fragment, the properties of which were analyzed with the aid of DFT methods and compared with those of the homologous non-fluorinated (CH3 )3 Au moiety. It was found that reductive elimination of CX3 -CX3 in the former (X=F) requires a much higher energy barrier than in the latter (X=H) and is therefore considerably less favored. This can be considered as one of the main features underlying the significantly higher stability associated to the (CF3 )3 Au fragment and its derivatives. This unsaturated, 14-electron species can be stabilized by coordination of any of the halide ligands, including fluoride. In fact, the whole series of anionic [PPh4 ][(CF3 )3 AuX] complexes (X=F, Cl, Br, I, CN) has now been isolated and conveniently characterized. Evidence for intermolecular decomposition pathways upon thermolysis in the condensed phase is presented.

4.
Chemistry ; 23(7): 1512-1515, 2017 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-27933670

RESUMO

The anionic trifluoromethylgold(I) derivatives [CF3 AuX]- , which have been prepared and isolated as their [PPh4 ]+ salts in good yield, undergo thermally induced difluorocarbene extrusion in the gas phase, giving rise to the mixed gold(I) fluorohalide complexes [F-Au-X]- (X=Cl, Br, I). These triatomic species have been detected by tandem mass spectrometry (MS2) experiments and their properties have been analyzed by DFT methods. The CF2 extrusion mechanism from the Au-CF3 moiety serves as a model for the CF2 insertion into the Au-F bond, since both reactivity channels are connected by the microreversibility principle.

5.
Chem Sci ; 6(10): 5506-5510, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28717445

RESUMO

The hexanuclear gold carbonyl cluster [PPh4]2[Au6(CF3)6Br2(CO)2] (4) has been obtained by spontaneous self-assembly of the following independent units: CF3AuCO (1) and [PPh4][Br(AuCF3)2] (3). The cyclo-Au6 aggregate 4, in which the components are held together by unassisted, fairly strong aurophilic interactions (Au···Au ∼310 pm), exhibits a cyclohexane-like arrangement with chair conformation. These aurophilic interactions also result in significant ν(CO) lowering: from 2194 cm-1 in the separate component 1 to 2171 cm-1 in the mixed aggregate 4. Procedures to prepare the single-bridged dinuclear component 3 as well as the mononuclear derivative [PPh4][CF3AuBr] (2) are also reported.

6.
Chemistry ; 19(43): 14540-52, 2013 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-24027236

RESUMO

Trifluoromethylation of AuCl3 by using the Me3 SiCF3 /CsF system in THF and in the presence of [PPh4 ]Br proceeds with partial reduction, yielding a mixture of [PPh4 ][Au(I) (CF3 )2 ] (1') and [PPh4 ][Au(III) (CF3 )4 ] (2') that can be adequately separated. An efficient method for the high-yield synthesis of 1' is also described. The molecular geometries of the homoleptic anions [Au(I) (CF3 )2 ](-) and [Au(III) (CF3 )4 ](-) in their salts 1' and [NBu4 ][Au(III) (CF3 )4 ] (2) have been established by X-ray diffraction methods. Compound 1' oxidatively adds halogens, X2 , furnishing [PPh4 ][Au(III) (CF3 )2 X2 ] (X=Cl (3), Br (4), I (5)), which are assigned a trans stereochemistry. Attempts to activate CF bonds in the gold(III) derivative 2' by reaction with Lewis acids under different conditions either failed or only gave complex mixtures. On the other hand, treatment of the gold(I) derivative 1' with BF3 ⋅OEt2 under mild conditions cleanly afforded the carbonyl derivative [Au(I) (CF3 )(CO)] (6), which can be isolated as an extremely moisture-sensitive light yellow crystalline solid. In the solid state, each linear F3 C-Au-CO molecule weakly interacts with three symmetry-related neighbors yielding an extended 3D network of aurophilic interactions (Au⋅⋅⋅Au=345.9(1) pm). The high $\tilde \nu $CO value (2194 cm(-1) in the solid state and 2180 cm(-1) in CH2 Cl2 solution) denotes that CO is acting as a mainly σ-donor ligand and confirms the role of the CF3 group as an electron-withdrawing ligand in organometallic chemistry. Compound 6 can be considered as a convenient synthon of the "Au(I) (CF3 )" fragment, as it reacts with a number of neutral ligands L, giving rise to the corresponding [Au(I) (CF3 )(L)] compounds (L=CNtBu (7), NCMe (8), py (9), tht (10)).

7.
Chemistry ; 19(1): 324-37, 2013 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-23165756

RESUMO

The action of moisture on the homoleptic organoplatinum(II) compound [NBu(4)](2)[Pt(CF(3))(4)] (1) gives rise to the carbonyl derivative [NBu(4)][Pt(CF(3))(3)(CO)] (2), which is itself moisture stable. However, treatment of compound 2 with HCl(aq) results in the formation of [NBu(4)][cis-Pt(CF(3))(2)Cl(CO)] (3), which undergoes degradation of an additional CF(3) group by further treatment with HCl(aq) in large excess, affording [NBu(4)][cis-Pt(CF(3))Cl(2)(CO)] (4). The carbonyl derivatives 2-4 are fairly stable species, in which the CO ligand, however, can be readily extruded by reaction with trimethylamine N-oxide (ONMe(3)). Thus, compound 2 reacts with ONMe(3) in the presence of a number of neutral or anionic ligands affording a series of singly or doubly charged derivatives with the general formulae [NBu(4)][Pt(CF(3))(3)(L)] [L = CNtBu (5), PPh(3) (6), P(o-tolyl)(3) (7), tht (8; tht = tetrahydrothiophene)] and [NBu(4)](2)[Pt(CF(3))(3)X] [X = Cl (9), Br (10), I (11)], respectively. Compound 2 also reacts with ONMe(3) and pyridin-2-thiol (C(5)H(5)NS) giving rise to the five-membered metallacyclic derivative [NBu(4)][Pt(CF(3))(2)(CF(2)NC(5)H(4)S-κC,κS)] (12), which can be viewed as a difluorocarbene species stabilized by intramolecular base coordination. On the other hand, treatment of compound 3 with ONMe(3) in the presence of C(5)H(5)NS yields the four-membered metallacyclic compound [NBu(4)][Pt(CF(3))(2)(NC(5)H(4)S-κN,κS)] (13). The geometries of the metallacycles in compounds 12 and 13 are compared. In the absence of any additional ligand, compound 3 undergoes dimerization producing the dinuclear species [NBu(4)](2)[{Pt(CF(3))(2)}(2)(µ-Cl)(2)] (14). Halide abstraction in the latter compound with AgClO(4) in THF yields the solvento compound cis-[Pt(CF(3))(2)(thf)(2)] (15). The highly labile character of the THF ligands in compound 15 makes this species a convenient synthon of the "cis-Pt(CF(3))(2)" unit.


Assuntos
Clorofluorcarbonetos de Metano/química , Complexos de Coordenação/química , Compostos Organoplatínicos/química , Cátions Bivalentes/química , Cristalografia por Raios X , Modelos Moleculares , Platina/química , Estereoisomerismo
8.
J Clin Exp Dent ; 4(2): e112-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24558535

RESUMO

OBJECTICS: The evolution of research activity during the last thirty years on regenerative periodontal surgery is studied. RESULTS: A small number of authors are highly productive with more than 10 publications on the subject each. 79,6% of authors have only produced one article on the subject. The co-authorship average is of 2,68 authors per paper, with a collaboration between 2 and 6 authors. Main journals on the field of regenerative periodontal surgery are Journal of Periodontology and Journal of Clinical Periodontology, which are ranked 14th and 1st in their category according to the Journal Citations Reports. The most used language is English, followed by Japanese and Italian, Spanish occupying the eighth position. CONCLUSIONS: A significant increase on scientific literature is observed, similar to the one Dentistry has had. A reduced number of authors account for most production. In the same token, there is a scarce professionalization of researchers in this field, where most of the authors are occasional. On the other hand, there are two very specialized journals on this topic. Key words:Bibliometrics, scientometrics periodontal regeneration, surgical periodontal treatment, scientific literature, scopus, scientific output.

10.
Dalton Trans ; 40(40): 10440-7, 2011 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-21766110

RESUMO

The homoleptic, square-planar trifluoromethylplatinate(II) compound [NBu(4)](2)[Pt(CF(3))(4)] (1) reacts with SOCl(2) undergoing oxidative addition of a S-Cl bond to give the octahedral species [NBu(4)](2)[trans-Pt(CF(3))(4)Cl(SOCl)] (4), that contains the unusual chlorosulfinyl ligand. Compound 4 readily evolves into the dichloro-derivative [NBu(4)](2)[cis-Pt(CF(3))(4)Cl(2)] (2), whereby the "Pt(CF(3))(4)" unit undergoes a stereochemical rearrangement from an initial square-planar (equatorial) geometry to a final sawhorse disposition within the global Pt octahedral environment. Compound 2 is more reactive than the corresponding [NBu(4)](2)[trans-Pt(CF(3))(4)Cl(2)] (3) stereoisomer and thus affords the trichloro-derivative [NBu(4)](2)[fac-Pt(CF(3))(3)Cl(3)] (5) by treatment with the stoichiometrically required amount of HCl(aq). Stereoisomer [NBu(4)](2)[mer-Pt(CF(3))(3)Cl(3)] (6) has been obtained by oxidative addition of Cl(2) to the organoplatinum(II) precursor [NBu(4)](2)[Pt(CF(3))(3)Cl]. All the synthetic procedures described here proceed in high yields and in a stereoselective manner. The optical properties of the cis-/trans-[Pt(CF(3))(4)Cl(2)](2-) and fac-/mer-[Pt(CF(3))(3)Cl(3)](2-) diastereomeric couples (diffuse reflectance) as well as the solid-state geometries of the latter couple (single-crystal X-ray diffraction methods) are conveniently compared.

11.
Chemistry ; 17(29): 8085-97, 2011 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-21647991

RESUMO

The homoleptic, square-planar organoplatinum(II) compound [NBu(4)](2) [Pt(CF(3))(4)] (1) undergoes oxidative addition of CF(3) I under mild conditions to give rise to the octahedral organoplatinum(IV) complex [NBu(4)](2) [Pt(CF(3))(5)I] (2). This highly trifluoromethylated species reacts with Ag(+) salts of weakly coordinating anions in Me(2)CO under a wet-air stream to afford the aquo derivative [NBu(4)][Pt(CF(3))(5) (OH(2))] (4) in around 75% yield. When the reaction of 2 with the same Ag(+) salts is carried out in MeCN, the solvento compound [NBu(4) ][Pt(CF(3))(5)(NCMe)] (5) is obtained in around 80% yield. The aquo ligand in 4 as well as the MeCN ligand in 5 are labile and can be cleanly replaced by neutral and anionic ligands to furnish a series of pentakis(trifluoromethyl)platinate(IV) compounds with formulae [NBu(4)][Pt(CF(3))(5) (L)] (L=CO (6), pyridine (py; 7), tetrahydrothiophene (tht; 8)) and [NBu(4)](2) [Pt(CF(3))(5)X] (X=Cl (9), Br (10)). The unusual carbonyl-platinum(IV) derivative [NBu(4)][Pt(CF(3))(5) (CO)] (6) is thermally stable and has a ν(CO) of 2194 cm(-1). The crystal structures of 2⋅CH(2)Cl(2), 5, [PPh(4) ][Pt(CF(3))(5)(CO)] (6'), and 7 have been established by X-ray diffraction methods. Compound 2 has shown itself to be a convenient entry to the chemistry of highly trifluoromethylated platinum compounds. To the best of our knowledge, compounds 2 and 4-10 are the organoelement compounds with the highest CF(3) content to have been isolated and adequately characterized to date.

13.
Chemistry ; 15(26): 6371-82, 2009 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-19449360

RESUMO

Chlorocarbon solvents (solv=CH(2)Cl(2), CHCl(3)) are suggested to play an active role in the oxidative addition of halogens, X(2) (X=Cl, Br, I), to homoleptic d(8) perfluoromethyl and -phenyl platinum(II) species [Pt(R(F))(4)](2-) (R(F)=CF(3), C(6)F(5)). The perfluoromethyl group, CF(3), has been found to be considerably less prone to undergo reductive elimination processes, and is, therefore, more suitable for stabilizing organoplatinum(IV) derivatives (see scheme).The equilibrium geometries of the homoleptic perfluorinated organoplatinate(II) anions [Pt(CF(3))(4)](2-) and [Pt(C(6)F(5))(4)](2-) have been computed at the B3P86/LANL2DZ level of theory. Remarkably good agreement with the experimentally determined structures has been obtained by X-ray diffraction methods. The reactivity of [NBu(4)](2)[Pt(CF(3))(4)] (1) towards halogens (Cl(2), Br(2), and I(2)) has been investigated by using a combined experimental and theoretical approach. The perfluoromethyl derivative 1 has been found to undergo clean oxidative addition of the three halogens under investigation, giving rise to [NBu(4)](2)[trans-Pt(CF(3))(4)X(2)] (X=Cl (7), Br (10), I (13)) in a quantitative and stereoselective way. In the low-temperature reaction of the perfluorophenyl derivative [NBu(4)](2)[Pt(C(6)F(5))(4)] (3) with Cl(2) or Br(2), the corresponding oxidative-addition products [NBu(4)](2)[trans-Pt(C(6)F(5))(4)X(2)] (X=Cl (14), Br (15)) can also be obtained. In the case in which X=Br and working in CHCl(3) at -55 degrees C, it has been possible to detect the formation of an intermediate species to which we assign the formula [trans-Pt(C(6)F(5))(4)Br(ClCHCl(2))](-) (16). The solvento complex 16 is thermally unstable and prone to undergo reductive elimination of C(6)F(5)--C(6)F(5). In the presence of PhCN, complex [NBu(4)][trans-Pt(C(6)F(5))(4)Br(NCPh)] (17) was isolated and structurally characterized. The reaction of 3 with I(2) gave no organoplatinum(IV) compound. Our comparative study reveals that the CF(3) group is especially suited to stabilize organometallic compounds in high oxidation states. This ability can be attributed to a combination of factors: its hardness, its high group electronegativity, its small size, and its reluctance to undergo reductive elimination processes.

14.
J. bras. med ; 86(6): 31-36, jun. 2004. ilus, tab
Artigo em Português | LILACS | ID: lil-401017

RESUMO

Os autores apresentam quatro casos de complicações decorrentes de acessos vasculares para hemodiálise em pacientes renais crônicos: a hipertensão venosa. Em duas situações ficaram bem caracterizadas clinicamente as repercussões hemodinâmicas à montante e à jusante da fístula e nas duas outras somente à jusante. Todos os pacientes desenvolveram sintomatologia que necessitou de algum tipo de intervenção. Em todos os casos, a simples ligadura dos ramos proximais e(ou) distais à fístula, com ou sem a sua interrupção definitiva, foi suficiente para a regressão da sintomatologia em poucos dias. Os pacientes foram operados com sucesso apenas com os achados do exame vascular, que indicavam direção de fluxo (palpação e frêmitos), e com a técnica cirúrgica utilizada para a construção da fístula, sem a utilização de nenhum exame complementar


Assuntos
Humanos , Fístula Arteriovenosa/complicações , Fístula Arteriovenosa/fisiopatologia , Fístula Arteriovenosa/terapia , Pressão Venosa , Doença Crônica/terapia , Insuficiência Renal Crônica/complicações , Diálise Renal
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