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1.
Sleep Health ; 10(2): 229-236, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38233280

RESUMEN

STUDY OBJECTIVES: Although sleep affects a range of waking behaviors, the majority of studies have focused on sleep loss with relatively little attention on sustained periods of adequate sleep. The goal of this study was to use an experimental design to examine the effect of both of these sleep patterns on cognitive performance in healthy adults. METHODS: This study used a randomized crossover design. Participants who regularly slept 7-9 hours/night completed two 6-week intervention conditions, adequate sleep (maintenance of habitual bed/wake times) and insufficient sleep (reduction in sleep of 1.5 hours relative to adequate sleep), separated by a 2-6weeks (median=43days) washout period. Cognitive functioning was evaluated at baseline and endpoint of each intervention using the NIH Toolbox Cognition Battery. General linear models contrasted scores following each condition to the baseline of the first condition; the baseline of the second condition was included to evaluate practice effects. RESULTS: Sixty-five participants (age 35.9 ± 4.9years, 89% women, 52% non-White race/ethnicity) completed study procedures. There was improvement in performance on the List Sorting Working Memory task after the adequate sleep condition that exceeded practice effects. Cognitive performance after insufficient sleep did not reach the level expected with practice and did not differ from baseline. A similar pattern was found on the Flanker Inhibitory Control and Attention task. CONCLUSIONS: These findings contribute to our understanding of the complex interplay between sleep and cognition and demonstrate that consistent, stable sleep of at least 7 hours/night improves working memory and response inhibition in healthy adults. CLINICAL TRIAL REGISTRATION: The manuscript reports on data from two clinical trials: Impact of Sleep Restriction on Performance in Adults (URL: https://clinicaltrials.gov/ct2/show/NCT02960776, ID Number: NCT02960776) and Impact of Sleep Restriction in Women (URL: https://clinicaltrials.gov/ct2/show/NCT02835261, ID Number: NCT02835261).


Asunto(s)
Cognición , Estudios Cruzados , Sueño , Humanos , Femenino , Masculino , Adulto , Privación de Sueño/psicología
2.
Cyberpsychol Behav Soc Netw ; 27(2): 105-110, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38265805

RESUMEN

The objectives of this research were to examine the contextual factors that impact individual's interpretation of their responsibility in the context of Deepfake videos. Using a test/retest methodology, a total of 1,023 respondents participated in a Deepfake survey instrument which measured perceptions of individual responsibility with respect to Deepfakes, individual concern with Deepfakes, and humorous perception of Deepfakes. The results of the study found that individual responsibility is negatively related to individual concern, indicating the externalization of responsibility for difficult to detect fake online videos designed to be convincing. Further, humorous perception and age impact the participants perception of individual responsibility. Younger participants were more likely to find Deepfakes humorous and this increased their perception of their own responsibility, potentially exposing them to greater harm from malicious Deepfakes.


Asunto(s)
Decepción , Humanos
3.
J Am Heart Assoc ; 12(20): e032078, 2023 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-37815115

RESUMEN

Background Insufficient sleep is associated with increased cardiovascular disease risk, but causality is unclear. We investigated the impact of prolonged mild sleep restriction (SR) on lipid and inflammatory profiles. Methods and Results Seventy-eight participants (56 women [12 postmenopausal]; age, 34.3±12.5 years; body mass index, 25.8±3.5 kg/m2) with habitual sleep duration 7 to 9 h/night (adequate sleep [AS]) underwent two 6-week conditions in a randomized crossover design: AS versus SR (AS-1.5 h/night). Total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol, triglycerides, and inflammatory markers (CRP [C-reactive protein], interleukin 6, and tumor necrosis factor-α) were assessed. Linear models tested effects of SR on outcomes in the full sample and by sex+menopausal status (premenopausal versus postmenopausal women+men). In the full sample, SR increased high-density lipoprotein cholesterol compared with AS (ß=1.2±0.5 mg/dL; P=0.03). Sex+menopausal status influenced the effects of SR on change in total cholesterol (P-interaction=0.04), LDL-C (P-interaction=0.03), and interleukin 6 (P-interaction=0.07). Total cholesterol and LDL-C decreased in SR versus AS in premenopausal women (total cholesterol: ß=-4.2±1.9 mg/dL; P=0.03; LDL-C: ß=-6.3±2.0 mg/dL; P=0.002). Given paradoxical effects of SR on cholesterol concentrations, we explored associations between changes in inflammation and end point lipids under each condition. Increases in interleukin 6 and tumor necrosis factor-α during SR tended to relate to lower LDL-C in premenopausal women (interleukin 6: ß=-5.3±2.6 mg/dL; P=0.051; tumor necrosis factor-α: ß=-32.8±14.2 mg/dL; P=0.027). Conclusions Among healthy adults, prolonged insufficient sleep does not increase atherogenic lipids. However, increased inflammation in SR tends to predict lower LDL-C in premenopausal women, resembling the "lipid paradox" in which low cholesterol associates with increased cardiovascular disease risk in proinflammatory conditions. Registration URL: https://www.clinicaltrials.gov; Unique identifiers: NCT02835261, NCT02960776.


Asunto(s)
Enfermedades Cardiovasculares , Masculino , Adulto , Humanos , Femenino , Adulto Joven , Persona de Mediana Edad , LDL-Colesterol , Privación de Sueño , Interleucina-6 , Factor de Necrosis Tumoral alfa , Ensayos Clínicos Controlados Aleatorios como Asunto , Colesterol , Triglicéridos , HDL-Colesterol , Inflamación
4.
Nutrients ; 13(3)2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33807690

RESUMEN

Poor sleep is a determinant of obesity, with overconsumption of energy contributing to this relationship. Eating behavior characteristics are predictive of energy intake and weight change and may underlie observed associations of sleep with weight status and obesity risk factors. However, relationships between sleep and dimensions of eating behavior, as well as possible individual differences in these relations, are not well characterized. Therefore, the aim of this study was to evaluate whether sleep behaviors, including duration, timing, quality, and regularity relate to dietary restraint, disinhibition, and tendency towards hunger and to explore whether these associations differ by sex. This cross-sectional study included 179 adults aged 20-73 years (68.7% women, 64.8% with BMI ≥ 25 kg/m2). Sleep was evaluated by accelerometry over 2 weeks. Eating behavior dimensions were measured with the Three-Factor Eating Questionnaire. Prolonged wake after sleep onset (WASO) (0.029 ± 0.011, p = 0.007), greater sleep fragmentation index (0.074 ± 0.036, p = 0.041), and lower sleep efficiency (-0.133 ± 0.051, p = 0.010) were associated with higher dietary restraint. However, higher restraint attenuated associations of higher WASO and sleep fragmentation with higher BMI (p-interactions < 0.10). In terms of individual differences, sex influenced associations of sleep quality measures with tendency towards hunger (p-interactions < 0.10). Stratified analyses showed that, in men only, higher sleep fragmentation index, longer sleep onset latency, and lower sleep efficiency were associated with greater tendency towards hunger (ß = 0.115 ± 0.037, p = 0.003, ß = 0.169 ± 0.072, p = 0.023, ß = -0.150 ± 0.055, p = 0.009, respectively). Results of this analysis suggest that the association of poor sleep on food intake could be exacerbated in those with eating behavior traits that predispose to overeating, and this sleep-eating behavior relation may be sex-dependent. Strategies to counter overconsumption in the context of poor quality sleep should be evaluated in light of eating behavior traits.


Asunto(s)
Conducta Alimentaria/fisiología , Hiperfagia/fisiopatología , Obesidad/etiología , Trastornos del Inicio y del Mantenimiento del Sueño/fisiopatología , Sueño , Actigrafía , Adulto , Anciano , Índice de Masa Corporal , Peso Corporal , Estudios Transversales , Encuestas sobre Dietas , Ingestión de Energía , Femenino , Humanos , Hambre , Hiperfagia/complicaciones , Masculino , Persona de Mediana Edad , Obesidad/fisiopatología , Factores de Riesgo , Factores Sexuales , Trastornos del Inicio y del Mantenimiento del Sueño/complicaciones , Encuestas y Cuestionarios , Factores de Tiempo , Adulto Joven
5.
Cyberpsychol Behav Soc Netw ; 24(3): 164-172, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33760667

RESUMEN

A 61 question survey was used to examine issues around "deepfake" technology. In total, 319 respondents answered questions around awareness, concerns, and the responsibility of online platforms around deepfakes. Awareness of deepfakes varies by intensity and type of social media use. Concerns about deepfakes are pronounced, but not uniform. A regression model examines the factors impacting the perceived responsibility of online platforms to regulate deepfakes. General concerns and the impacts people believe deepfakes will make are significant. However, the more humorous aspects of deepfakes and a perception of individual responsibility negatively impact the perceived need for platforms to address the risks of deepfakes. There is little confidence in the ability of technology to solve the problem of deepfakes, but this does not reduce the desire for online platforms to implement a deepfake identification technology. This research has implications for users of social media, social media platforms, technology developers, and broader society.


Asunto(s)
Decepción , Conducta Social , Medios de Comunicación Sociales/estadística & datos numéricos , Responsabilidad Social , Grabación en Video , Femenino , Humanos , Masculino , Encuestas y Cuestionarios
6.
J Phys Chem B ; 117(46): 14557-67, 2013 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-24195584

RESUMEN

Thermally convertible organic materials are useful for the fabrication of multilayered thin film electronic devices such as solar cells. However, substantial changes in molecular ordering can occur during the conversion process that may lead to multiple polymorphs having differing electronic properties. In-situ grazing incidence wide-angle X-ray scattering with 2-D detection (2-D GIWAXS) was used to study the changes in the thin film crystal structure, texture, and crystallite size of a convertible small-molecule electron donor, tetrabenzoporphyrin (BP), during thermal conversion from the precursor bicycloporphyrin (CP) and the resulting crystal-crystal phase transition from a metastable phase (phase I) to a stable phase (phase II). The annealing temperature and the presence of an underlying BP layer both affect the phase-transition behavior. Phase II has a much weaker degree of crystalline texture than phase I, attributed to changes in molecular packing to achieve a herringbone arrangement. The unit cell for phase I was determined by electron diffraction and GIWAXS, and the thin film structure of phase II matched the previously determined bulk structure. The texture of crystallites in phase II was characterized by the simulation of the GIWAXS pattern. Transmission electron microscopy revealed differences in the morphology, grain size, and film coverage of the two polymorphs. Peak shape analysis with corrections for geometric smearing and paracrystalline disorder showed an increase in crystallite size from phase I to phase II. These results demonstrate the utility of in-situ 2-D GIWAXS in revealing polymorphic phases during the structural transition of thermally convertible organic semiconductors, the presence of which may impact the performance of solar cells.

7.
J Am Chem Soc ; 134(38): 16040-6, 2012 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-22970828

RESUMEN

A novel strategy for the synthesis of fully conjugated donor-acceptor block copolymers, in a single reaction step employing Stille coupling polymerization of end-functional polythiophene and AA + BB monomers, is presented. The unique donor-acceptor structure of these block copolymers provides a rich self-assembly behavior, with the first example of a fully conjugated donor-acceptor block copolymer having two separate crystalline domains being obtained.

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