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1.
Chem Sci ; 14(21): 5689-5698, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37265728

RESUMO

We present the synthesis, characterization and radical ring-opening polymerization (rROP) capabilities of thionoisochromanone (TIC), a fungi-derivable thionolactone. TIC is the first reported six-membered thionolactone to readily homopolymerize under free radical conditions without the presence of a dormant comonomer or repeated initiation. Even more, the resulting polymer is fully degradable under mild, basic conditions. Computations providing molecular-level insights into the mechanistic and energetic details of polymerization identified a unique S,S,O-orthoester intermediate that leads to a sustained chain-end. This sustained chain-end allowed for the synthesis of a block copolymer of TIC and styrene under entirely free radical conditions without explicit radical control methods such as reversible addition-fragmentation chain transfer polymerization (RAFT). We also report the statistical copolymerization of ring-retained TIC and styrene, confirmed by elemental analysis and energy-dispersive X-ray spectroscopy (EDX). Computations into the energetic details of copolymerization indicate kinetic drivers for ring-retaining behavior. This work provides the first example of a sustainable feedstock for rROP and provides the field with the first six-membered monomer susceptible to rROP, expanding the monomer scope to aid our fundamental understanding of thionolactone rROP behavior.

2.
Chem Sci ; 14(24): 6806, 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37350818

RESUMO

[This corrects the article DOI: 10.1039/D2SC06040J.].

3.
J Pediatr Psychol ; 47(7): 769-784, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35348738

RESUMO

AIM: Pediatric food allergy represents a significant public health burden. In order to avoid allergen consumption, adequate management requires daily vigilance and involvement from parents, frequently leading to increased parental anxiety. While specific anxiogenic parenting practices (i.e., parenting behaviors which may aid in the development and/or exacerbation of childhood anxiety) have been documented within this population, to this point, these behaviors have not been systematically measured. OBJECTIVES: The current study aimed to develop and examine a parent-report scale designed to measure anxiogenic parenting behaviors related to food allergy. METHODS: Participants included 177 parents of children with food allergy recruited online using Amazon Mechanical Turk (mTurk). An exploratory factor analysis was conducted to determine the factor structure of the newly developed scale. Subsequently, psychometric properties (e.g., construct validity) were examined via correlational analyses. RESULTS: Results indicated a 24-item, 3 factor (Factor 1: Involvement in Food Allergy; Factor 2: Worry about Food Allergy; Factor 3: Autonomy Promotion) scale, which accounted for 53.11% of the total variance. The Kaiser-Meyer-Olkin measure was acceptable, KMO = 0.872 and Bartlett's test of sphericity indicated sufficient correlations between items (χ2(378)=2568.95). All subscales demonstrated strong internal consistency (Involvement in Food Allergy: α = .880; Worry about Food Allergy: α = .892; Autonomy Promotion α = .796) as well as convergent and discriminant validity. CONCLUSIONS: Results support the overall psychometric properties of the scale. Interpretations, limitations, and future directions are discussed.


Assuntos
Ansiedade , Hipersensibilidade Alimentar , Poder Familiar , Ansiedade/diagnóstico , Criança , Análise Fatorial , Hipersensibilidade Alimentar/diagnóstico , Hipersensibilidade Alimentar/psicologia , Humanos , Poder Familiar/psicologia , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários
4.
Res Child Adolesc Psychopathol ; 49(12): 1635-1648, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34236586

RESUMO

Children who experience obsessive-compulsive symptoms (OCS) may be at risk for developing Obsessive-Compulsive Disorder (OCD). The current study aimed to investigate developmental trajectories of OCS, as well as possible predictors, within a community-based sample of children. Children (N = 1147) from the longitudinal NICHD Study of Early Child Care and Youth Development (SECCYD) were assessed for OCS, via the Child Behavioral Checklist - Obsessive-Compulsive Scale (OCS-8), eight times between Pre-Kindergarten (54 months; Pre-K) and High School (15 years of age; HS.) Participants were recruited within the United States and included only maternal caregivers. Preliminary analyses indicated that approximately 3% of the sample was above the diagnostic cutoff score on the OCS-8 at the High School time-point. Latent growth models tested symptom trajectories. Findings demonstrated three groups of OCS trajectories. Most children fell within a low symptomatology group (the No Peak group) with low OCS across all time points. Two additional OCS trajectories were also demonstrated: Pre-K Peak (high to low OCS across time) and HS Peak (low to high OCS across time). Both higher attention problems and greater depression/anxiety symptoms at the Pre-K time point predicted children's membership in the Pre-K Peak or HS Peak groups compared to the No Peak group. Membership within the HS Peak group predicted a high likelihood of children's OCS being above previously established cutoff scores for an OCD diagnosis at age 15 years. Membership within either the Pre-K Peak or No Peak groups predicted a low likelihood. This study provides new evidence for the existence of different developmental trajectories for youth with OCS. From a clinical perspective, these results may have important implications when considering the identification and early intervention of childhood OCS and OCD within the community.


Assuntos
Transtornos do Comportamento Infantil , Transtorno Obsessivo-Compulsivo , Adolescente , Lista de Checagem , Criança , Humanos , Transtorno Obsessivo-Compulsivo/diagnóstico , Instituições Acadêmicas , Estados Unidos
6.
J Pediatr Psychol ; 45(1): 101-109, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31845999

RESUMO

OBJECTIVE: Pediatric food allergy (FA) is a serious health condition that has become increasingly prevalent. Parents often play a primary role in assessing and managing risk for their child's FAs, making it critical that they remain informed of the most recent guidelines for FA management. This study aimed to examine if diagnostic source (i.e., pediatrician vs. allergist) and child- and parent-level variables predicted parental FA knowledge using a comprehensive measure. METHODS: The Food Allergy Knowledge Test (FAKT) was administered to parents (N = 518) of children aged 3-17 years with (n = 349) and without (n = 169; i.e., control group) FAs using internet-sampling procedures. The sample was further partitioned into parents of children diagnosed by an allergist or a pediatrician, and control group parents who did or did not endorse knowing someone with an FA. RESULTS: Significant group differences were found with respect to the overall FAKT score and diagnostic source. Among the FA group, parental relationship to child, income, identification with a minority status, parental anxiety, and child possession of an emergency action plan were significant predictors of FAKT scores. CONCLUSIONS: Knowledge of FA was poor across all groups. Education for caregivers both with and without food-allergic children is important to ensure FA safety in multiple settings. Future directions and limitations are discussed.


Assuntos
Hipersensibilidade Alimentar , Conhecimentos, Atitudes e Prática em Saúde , Pais , Adolescente , Cuidadores , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Inquéritos e Questionários
7.
Inorg Chem ; 57(6): 3451-3457, 2018 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-29485872

RESUMO

Aluminum alkoxide complexes supported by salen ligands [salen = N, N'-bis(salicylaldimine)-2-methylpropane-1,2-diamine or N, N'-bis(salicylaldimine)-2,2-dimethylpropane-1,3-diamine] with o-adamantyl substituents have been synthesized and investigated for the polymerization of ε-caprolactone. Geometric analysis of the catalysts used for the reaction reveals the metal coordination geometries to be intermediate between square-pyramidal and trigonal-bipyramidal. A detailed kinetic study accompanied by density functional theory modeling of key mechanistic steps of the reaction suggest that, in addition to the length of the backbone linker, the o-aryl substituents have a significant impact on the catalyst's reactivity. Bulky ortho substituents favorably distort the precatalyst geometry and thereby foster the achievement of the rate-limiting transition-state geometry at low energetic cost, thus accelerating the reaction.

8.
Behav Modif ; 42(6): 885-913, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29319333

RESUMO

Although science's understanding (e.g., etiology, maintaining factors, etc.) of pediatric anxiety and related problems has grown substantially over recent years, several aspects to anxiety in youths remain elusive, particularly with relation to executive functioning. To this end, the current study sought to examine several facets to executive functioning (i.e., cognitive flexibility, inhibition, planning, working memory) within a transdiagnostic sample of youths exhibiting varying degrees of anxiety symptoms. One hundred six youths completed a comprehensive battery, including several self-report measures (e.g., Multidimensional Anxiety Scale for Children [MASC] or MASC-2) and an automated neurocognitive battery of several executive functioning tasks (Intradimensional/Extradimensional [IDED], Stop Signal [SST], Spatial Span [SSP], Stockings of Cambridge [SOC] tasks). Regression analyses indicated that youths exhibiting marked anxiety symptoms demonstrated increased planning time and probability of inhibition compared with youths with minimal or no anxiety symptoms. Youths with marked anxiety symptoms similarly demonstrated better cognitive flexibility (i.e., set shifting) compared with youths with minimal anxiety. In addition, analyses indicated a trend such that youths exhibiting marked anxiety symptoms demonstrated poorer working memory compared with youths with no anxiety symptoms. Group classification did not predict remaining outcomes. Limitations and future areas of research are discussed.


Assuntos
Ansiedade/psicologia , Função Executiva , Inibição Psicológica , Memória de Curto Prazo , Adolescente , Criança , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Análise de Regressão
9.
Behav Modif ; 42(6): 864-884, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29254364

RESUMO

Cognitive flexibility (CF), a subdomain of executive functioning (EF), involves abilities such as set shifting and reversal learning. Some variability in CF is normative across youth due to the gradual refinement of broader EF along with the prefrontal cortex. Prior research has suggested that a supportive parenting environment contributes to strong EF, whereas harsh/controlling parenting is associated with deficits. The current investigation explores whether certain parenting practices (e.g., parental accommodation, over-involvement, modeling) are associated with such deficits. Anxiogenic parenting and CF were assessed in 112 youth aged 9 to 17 years, with results demonstrating that parenting practices were not predictive of CF in these youth. Age accounted for the majority of differences in set shifting performance, potentially emphasizing the influence of parenting at different stages of development. Accordingly, future research is necessary to determine the potential impact of anxiogenic parenting at specific points in the development of CF.


Assuntos
Adaptação Psicológica , Ansiedade/psicologia , Cognição , Função Executiva , Poder Familiar/psicologia , Reversão de Aprendizagem , Adolescente , Criança , Feminino , Humanos , Masculino
10.
Inorg Chem ; 56(22): 14366-14372, 2017 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-29116765

RESUMO

The ring-opening transesterification polymerization (ROTEP) of rac-lactide (rac-LA) using LXZn catalysts (LX = ligand having phenolate, amine, and pyridine donors with variable para substituents X on the bound phenolate donor; X = NO2, Br, t-Bu, OMe) was evaluated through kinetics experiments and density functional theory, with the aim of determining how electronic modulation of the ligand framework influences polymerization rate, selectivity, and control. After determination that zinc-ethyl precatalysts required 24 h of reaction with benzyl alcohol to convert to active alkoxide complexes, the subsequently formed species proved to be active and fairly selective, polymerizing up to 300 equiv of rac-LA in 6-10 min while yielding isotactic (Pm = 0.72-0.78) polylactide (PLA) with low dispersities: D = 1.06-1.17. In contrast to previous work with aluminum catalysts for which electronic effects of ligand substituents were significant (Hammett ρ = +1.2-1.4), the LXZn systems exhibited much less of an effect (ρ = +0.3). Density functional calculations revealed details of the initiation and propagation steps, enabling insights into the high isotacticity and the insensitivity of the rate on the identity of X.

11.
Obesity (Silver Spring) ; 25(6): 1014-1021, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28437597

RESUMO

OBJECTIVE: To evaluate a commercial online weight loss program and activity tracker, which are popular but have unknown efficacy. METHODS: Two hundred seventy-nine participants with BMI 27 to 40 kg/m2 were randomized to 12 months of the Weight Watchers Online program alone (WWO) or with the ActiveLink® activity tracking device (WWO+AL) or an online newsletter (Control). RESULTS: Weight losses at 3 months were significantly greater in WWO (2.7 kg [95% confidence interval (CI), 2.0-3.5 kg] than Control (1.3 kg [95% CI, 0.5-2.0 kg]; P = 0.01); neither differed from WWO+AL (2.0 kg [95% CI, 1.3-2.7 kg]; Ps > 0.56). Significantly more WWO participants (24.5%) achieved ≥ 5% weight loss at 3 months than Control (9.4%) (P = 0.01); neither differed from WWO+AL (17.6%) (Ps = 0.13-0.28). At 12 months, there were no significant differences between groups in weight loss (Ps > 0.52). WWO (25.5%) continued to have a higher proportion of participants achieving ≥ 5% weight loss than Control (12.9%) (P = 0.04); neither differed from WWO+AL (14.3%) (Ps > 0.10). There were no significant between-group differences in change in physical activity (Ps > 0.17). CONCLUSIONS: WWO produced significantly more weight loss at 3 months relative to Control, but not at 12 months. Significantly more WWO than Control participants lost ≥ 5% at both 3 and 12 months. Participants receiving an activity tracking device did not achieve greater weight loss or physical activity increases than those in a Control condition.


Assuntos
Exercício Físico/fisiologia , Monitores de Aptidão Física/estatística & dados numéricos , Obesidade/terapia , Telemedicina/estatística & dados numéricos , Redução de Peso/fisiologia , Programas de Redução de Peso/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Obes Sci Pract ; 2(1): 75-82, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27812381

RESUMO

OBJECTIVE: The typical Western diet is deficient in omega-3 and high in omega-6 fatty acids (FAs). These FAs may play a role in depressive symptoms via inflammatory processes, especially in the context of obesity, a pro-inflammatory state. This study investigated associations between omega-3 and omega-6 FA intake and depressive symptoms in adults seeking behavioural weight loss treatment (BWLT). METHODS: One hundred eighty-eight persons with overweight or obesity (83.50% women, 93.10% White, 55.01 ± 10.09 years old, body mass index 36.02 ± 15.79 kg/m) seeking BWLT completed the Block Food Frequency Questionnaire, which provides estimates of dietary FA intake, daily total energy intake (TEI) and macronutrient composition of the diet. Depressive symptoms were measured via the Center for Epidemiological Studies Depression Scale. Correlation and linear regression estimated associations between depressive symptoms and FAs. RESULTS: On average, participants reported consuming 1866.2 ± 665.1 kcals/d, with 38% of TEI from fat and an omega-6:3 ratio of 9.2 (13.9 g omega-6 to 1.5 g omega-3). In univariate models, omega-6 intake was associated with depressive symptoms (r = .182, p = .012); however, this association was no longer statistically significant after controlling for TEI. Omega-3 intake was not associated with depressive symptoms. CONCLUSION: The expected association between omega-3 and omega-6 FAs and depressive symptoms was largely unsupported. A robust association between FA intake and depressive symptoms may have been masked by a high level of chronic inflammation in this sample caused by excess weight and overall poor diet. Additional research is needed to determine whether BWLT improves FA intake, and whether associations between FA intake and depressive symptoms are strengthened after successful weight loss and improved diet.

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