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1.
Ann Behav Med ; 58(7): 463-473, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38828482

RESUMO

BACKGROUND: Nearly 40% of unplanned pregnancies in the USA are the result of inconsistent or incorrect contraceptive use. Finding ways to increase women's comfort and satisfaction with contraceptive use is therefore critical to public health. One promising pathway for improving patient outcomes is through the use of digital decision aids that assist women and their physicians in choosing a contraceptive option that women are comfortable with. Testing the ability of these aids to improve patient outcomes is therefore a necessary first step toward incorporating this technology into traditional physician appointments. PURPOSE: To evaluate the effectiveness of a novel contraceptive decision aid at minimizing decisional conflict and increasing comfort with contraception among adult women. METHODS: In total, 310 adult women were assigned to use either the Tuune contraceptive decision aid or a control aid modeled after a leading online contraceptive prescriber's patient intake form. Participants then completed self-report measures of decisional conflict, contraceptive expectations, satisfaction, and contraceptive use intentions. Individual between-subjects analysis of variance (ANOVA) models were used to examine these outcomes. RESULTS: Women using the Tuune decision aid (vs. those using the control aid) reported lower decisional conflict, more positive contraceptive expectations, greater satisfaction with the decision aid and recommendation, and more positive contraceptive use intentions. CONCLUSIONS: Use of Tuune improved each of the predicted patient outcomes relative to a control decision aid. Online decision aids, particularly when used alongside physician consultations, may be an effective tool for increasing comfort with contraceptive use. CLINICAL TRIALS REGISTRATION #: NCT05177783, ClinicalTrials.gov, https://clinicaltrials.gov/ct2/show/NCT05177783.


Digital decision aids that help women and their physicians choose contraceptive options that women are most comfortable with present one promising way to improve contraceptive use outcomes, such as avoiding unplanned pregnancies. However, current decision aids have been found to struggle in helping improve women's satisfaction with and confidence in their contraceptive choices. The aim of this study was to test the effectiveness of a new digital decision aid, named Tuune, at helping improve women's confidence and comfort with contraception. Three hundred and ten adult women were randomly assigned to use and then receive a contraceptive recommendation from either the Tuune decision aid or a control aid designed after leading traditional health intake forms. Women's confidence and satisfaction with the aids, as well as their contraceptive recommendation, were then compared between groups. We found good evidence to suggest that women using the Tuune contraceptive decision aid were more satisfied and positive about their contraceptive choices and reported greater intentions to use contraception with increased confidence compared to women who used the control decision aid. New online decision aids, like Tuune, may be an effective tool for increasing women's comfort and experiences using contraception.


Assuntos
Comportamento Contraceptivo , Técnicas de Apoio para a Decisão , Satisfação do Paciente , Humanos , Feminino , Adulto , Comportamento Contraceptivo/psicologia , Adulto Jovem , Anticoncepção/métodos , Adolescente , Tomada de Decisões
2.
J Am Chem Soc ; 144(39): 17939-17954, 2022 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-36130605

RESUMO

The kinetics of hydride transfer from Re(Rbpy)(CO)3H (bpy = 4,4'-R-2,2'-bipyridine; R = OMe, tBu, Me, H, Br, COOMe, CF3) to CO2 and seven different cationic N-heterocycles were determined. Additionally, the thermodynamic hydricities of complexes of the type Re(Rbpy)(CO)3H were established primarily using computational methods. Linear free-energy relationships (LFERs) derived by correlating thermodynamic and kinetic hydricities indicate that, in general, the rate of hydride transfer increases as the thermodynamic driving force for the reaction increases. Kinetic isotope effects range from inverse for hydride transfer reactions with a small driving force to normal for reactions with a large driving force. Hammett analysis indicates that hydride transfer reactions with greater thermodynamic driving force are less sensitive to changes in the electronic properties of the metal hydride, presumably because there is less buildup of charge in the increasingly early transition state. Bronsted α values were obtained for a range of hydride transfer reactions and along with DFT calculations suggest the reactions are concerted, which enables the use of Marcus theory to analyze hydride transfer reactions involving transition metal hydrides. It is notable, however, that even slight perturbations in the steric properties of the Re hydride or the hydride acceptor result in large deviations in the predicted rate of hydride transfer based on thermodynamic driving forces. This indicates that thermodynamic considerations alone cannot be used to predict the rate of hydride transfer, which has implications for catalyst design.


Assuntos
Rênio , 2,2'-Dipiridil , Dióxido de Carbono , Cinética , Termodinâmica
3.
Adv Synth Catal ; 362(22): 5062-5078, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33384575

RESUMO

Palladium(II) precatalysts are used extensively to facilitate cross-coupling reactions because they are bench stable and give high activity. As a result, precatalysts such as Buchwald's palladacycles, Organ's PEPPSI species, Nolan's allyl-based complexes, and Yale's 1-tert-butylindenyl containing complexes, are all commercially available. Comparing the performance of the different classes of precatalysts is challenging because they are typically used under different conditions, in part because they are reduced to the active species via different pathways. However, within a particular class of precatalyst, it is easier to compare performance because they activate via similar pathways and are used under the same conditions. Here, we evaluate the activity of different allyl-based precatalysts, such as (η3-allyl)PdCl(L), (η3-crotyl)PdCl(L), (η3-cinnamyl)PdCl(L), and (η3-1-tert-butylindenyl)PdCl(L) in Suzuki-Miyaura reactions. Specifically, we evaluate precatalyst performance as the ancillary ligand (NHC or phosphine), reaction conditions, and substrates are varied. In some cases, we connect relative activity to both the mechanism of activation and the prevalence of the formation of inactive palladium(I) dimers. Additionally, we compare the performance of in situ generated precatalysts with commonly used palladium sources such as tris(dibenzylideneacetone)dipalladium(0) (Pd2dba3), bis(acetonitrile)dichloropalladium(II) (Pd(CH3CN)2Cl2), and palladium acetate. Our results provide information about which precatalyst to use under different conditions.

4.
Sci Rep ; 13(1): 8379, 2023 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-37225722

RESUMO

Many species exhibit seasonal patterns of breeding. Although humans can shield themselves from many season-related stressors, they appear to exhibit seasonal patterns of investment in reproductive function nonetheless, with levels of sex steroid hormones being highest during the spring and summer months. The current research builds on this work, examining the relationship between day length and ovarian function in two large samples of women using data from the Natural Cycles birth control application in each Sweden and the United States. We hypothesized that longer days would predict higher ovulation rates and sexual motivation. Results revealed that increasing day length duration predicts increased ovulation rate and sexual behavior, even while controlling for other relevant factors. Results suggest that day length may contribute to observed variance in women's ovarian function and sexual desire.


Assuntos
Cruzamento , Fotoperíodo , Humanos , Feminino , Anticoncepção , Investimentos em Saúde , Ovulação
5.
Chem Sci ; 13(8): 2391-2404, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35342547

RESUMO

The insertion of carbon dioxide into metal element σ-bonds is an important elementary step in many catalytic reactions for carbon dioxide valorization. Here, the insertion of carbon dioxide into a family of group 10 alkyl complexes of the type (RPBP)M(CH3) (RPBP = B(NCH2PR2)2C6H4 -; R = Cy or t Bu; M = Ni or Pd) to generate κ1-acetate complexes of the form (RPBP)M{OC(O)CH3} is investigated. This involved the preparation and characterization of a number of new complexes supported by the unusual RPBP ligand, which features a central boryl donor that exerts a strong trans-influence, and the identification of a new decomposition pathway that results in C-B bond formation. In contrast to other group 10 methyl complexes supported by pincer ligands, carbon dioxide insertion into (RPBP)M(CH3) is facile and occurs at room temperature because of the high trans-influence of the boryl donor. Given the mild conditions for carbon dioxide insertion, we perform a rare kinetic study on carbon dioxide insertion into a late-transition metal alkyl species using ( t BuPBP)Pd(CH3). These studies demonstrate that the Dimroth-Reichardt parameter for a solvent correlates with the rate of carbon dioxide insertion and that Lewis acids do not promote insertion. DFT calculations indicate that insertion into ( t BuPBP)M(CH3) (M = Ni or Pd) proceeds via an SE2 mechanism and we compare the reaction pathway for carbon dioxide insertion into group 10 methyl complexes with insertion into group 10 hydrides. Overall, this work provides fundamental insight that will be valuable for the development of improved and new catalysts for carbon dioxide utilization.

6.
Organometallics ; 40(14): 2332-2344, 2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35719693

RESUMO

The synthesis of triarylmethanes via Pd-catalyzed Suzuki-Miyaura reactions between diarylmethyl 2,3,4,5,6-pentafluorobenzoates and aryl boronic acids is described. The system operates at mild conditions and has a broad substrate scope, including the coupling of diphenylmethanol derivatives that do not contain extended aromatic substituents. This is significant as these substrates, which result in the types of triarylmethane products that are prevalent in pharmaceuticals, have not previously been compatible with systems for diarylmethyl ester coupling. Further, the reaction can be performed stereospecifically to generate stereo-inverted products. On the basis of DFT calculations, it is proposed that the oxidative addition of the diarylmethyl 2,3,4,5,6-pentafluorobenzoate substrate occurs via an SN2 pathway, which results in the inverted products. Mechanistic studies indicate that oxidative addition of the diarylmethyl 2,3,4,5,6-pentafluorobenzoate substrates to (IPr)Pd(0) results in the selective cleavage of the O-C(benzyl) bond in part because of a stabilizing η3-interaction between the benzyl ligand and Pd. This is in contrast to previously described Pd-catalyzed Suzuki-Miyaura reactions involving phenyl esters, which involve selective cleavage of the C(acyl)-O bond, because there is no stabilizing η3-interaction. It is anticipated that this fundamental knowledge will aid the development of new catalytic systems, which use esters as electrophiles in cross-coupling reactions.

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