Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 111
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
Ann Behav Med ; 58(3): 167-178, 2024 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-38166169

RESUMEN

BACKGROUND: The Transtheoretical Model (TTM) has been the basis of health promotion programs, which are, for example, used to tailor behavioral interventions according to the stages of change. Empirical studies have shown that the TTM effectively describes the processes of behavioral adaptation to acquire healthier lifestyles; however, it has been argued that TTM-based interventions are not superior to non-TTM-based interventions for promoting physical activity (PA). Evidence has also highlighted some inconsistencies with theoretical assumptions, especially regarding how each process-of-change strategy emerges across the stages. PURPOSE: Therefore, we investigated (a) how well the TTM describes the distributional characteristics of PA levels as well as other relevant variables (e.g., process of change, self-efficacy) across stages, and (b) how predictive the TTM variables are of PA levels within each stage. METHODS: We analyzed data from 20,573 Japanese-speaking adults who completed online questionnaires on PA and TTM variables. RESULTS: The results replicated previous findings that stage membership is associated with PA, the process of change, decisional balance, and self-efficacy, albeit with inconclusive evidence of temptations. Regression analyses revealed that some processes of change (self-reevaluation, reinforcement management, and self-liberation) were more predictive of PA in pre-active stages than in post-action stages; self-efficacy was predictive of PA only in the maintenance stage but not in the other stages. CONCLUSIONS: Overall, the data support the theoretical assumptions of the TTM, but the stage specificity of the active processes may not always be consistent with the theory.


The Transtheoretical Model has been the basis of many behavioral interventions for promoting physical activity. One of the key concepts of the model is the stage of change, which is a framework to help understand the readiness to begin physical activity and exercise. The model assumes five progressive stages of behavior change (e.g., the precontemplation stage, where people have no intention to change behavior; the maintenance stage, where people have continued physical activity for a long enough period), through which individuals acquire an active lifestyle. The model also assumes that different strategies for behavior change are appropriate at different stages and, confidence and attitudes toward physical activity vary dynamically across stages. The current study examined how valid these theoretical assumptions using data from 20,573 Japanese-speaking adults. The data overall supported the assumptions of the Transtheoretical Model, for example, highlighting the importance of enhancing awareness about the causes and (dis)advantages of being (in)active at earlier stages. Although some inconsistencies were identified (some strategies were not as useful as the model assumed), these findings may suggest that the Transtheoretical Model holds universal theoretical value as a descriptive model of behavioral change for active lifestyle across Western and East Asian populations.


Asunto(s)
Ejercicio Físico , Modelo Transteórico , Adulto , Humanos , Estudios Transversales , Japón , Promoción de la Salud/métodos , Autoeficacia , Conductas Relacionadas con la Salud
2.
Psychother Psychosom ; 93(1): 24-35, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38176391

RESUMEN

INTRODUCTION: Schema therapy (ST) reduces depressive symptoms, but clinical trials have not investigated its effectiveness for patients suffering from severe forms of depression and high rates of comorbidities. There is high demand for exploring and improving treatments for this patient group. The objective of the current study was to evaluate whether ST is more effective than individual supportive therapy (IST) and noninferior compared with cognitive behavioral therapy (CBT) in treating depression. METHODS: For this clinical trial, medicated patients were recruited in inpatient and day clinic settings. The major inclusion criteria were age between 18 and 75 years and primary diagnosis of depression without psychotic symptoms. A total of 292 participants were randomized to ST, CBT, or IST and received 7 weeks of psychotherapy (up to 14 individual and 14 group sessions). The primary outcome was change in depression severity after treatment measured by Beck Depression Inventory-II. Primary test for efficacy was superiority of ST over IST. Secondary test was noninferiority of ST compared with CBT. Multilevel modeling was conducted. The results at 6-month follow-up were explored. RESULTS: Across treatment, ST was not superior to IST. Secondary outcome analyses and completer analyses showed similar results. However, ST showed clinically relevant noninferiority compared with CBT. CONCLUSION: ST for depression as part of a psychiatric care program showed clinical noninferiority compared to CBT, without being superior to IST. ST represents a potentially useful addition to the therapeutic repertoire for the treatment of depression but its efficacy, including long-term efficacy, should be evaluated further.


Asunto(s)
Terapia Cognitivo-Conductual , Terapia de Esquemas , Humanos , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Depresión/terapia , Pacientes Internos , Terapia Cognitivo-Conductual/métodos , Psicoterapia/métodos , Resultado del Tratamiento
3.
BMC Nephrol ; 25(1): 342, 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-39390382

RESUMEN

BACKGROUND: Hypertensive emergency is a critical disease that causes multiple organ injuries. Although the renin-angiotensin-aldosterone system (RAS) is enormously activated in this disorder, whether the RAS contributes to the development of the organ damage has not been fully elucidated. This cross-sectional study was conducted to characterize the association between RAS and the organ damage in patients with hypertensive emergencies. METHODS: We enrolled 63 patients who visited our medical center with acute severe hypertension and multiple organ damage between 2012 and 2020. Hypertensive target organ damage was evaluated on admission, including severe kidney impairment (eGFR less than 30 mL/min/1.73 m2, SKI), severe retinopathy, concentric left ventricular hypertrophy (c-LVH), thrombotic microangiopathy (TMA), heart failure with reduced ejection fraction (HFrEF) and cerebrovascular disease. Then, whether each organ injury was associated with blood pressure or a plasma aldosterone concentration was analyzed. RESULTS: Among 63 patients, 31, 37, 43 and 8 cases manifested SKI, severe retinopathy, c-LVH and ischemic stroke, respectively. All populations with the organ injuries except cerebral infarction had higher plasma aldosterone concentrations than the remaining subset but exhibited a variable difference in systolic or diastolic blood pressure. Twenty-two patients had a triad of SKI, severe retinopathy and c-LVH, among whom 5 patients manifested TMA. Furthermore, the number of the damaged organs was correlated with plasma aldosterone levels (Spearman's coefficient = 0.50), with a strong association observed between plasma aldosterone (≥ 250 pg/mL) and 3 or more complications (odds ratio = 9.16 [95%CI: 2.76-30.35]). CONCLUSION: In patients with hypertensive emergencies, a higher aldosterone level not only contributed to the development of the organ damage but also was associated with the number of damaged organs in each patient.


Asunto(s)
Aldosterona , Hipertensión , Humanos , Estudios Transversales , Masculino , Femenino , Aldosterona/sangre , Hipertensión/complicaciones , Anciano , Persona de Mediana Edad , Sistema Renina-Angiotensina/fisiología , Urgencias Médicas , Microangiopatías Trombóticas/sangre , Microangiopatías Trombóticas/etiología , Insuficiencia Cardíaca/sangre , Retinopatía Hipertensiva/etiología , Retinopatía Hipertensiva/sangre , Hipertrofia Ventricular Izquierda/etiología , Hipertrofia Ventricular Izquierda/sangre , Insuficiencia Multiorgánica/etiología , Insuficiencia Multiorgánica/sangre , Accidente Cerebrovascular Isquémico/sangre , Insuficiencia Renal/sangre , Crisis Hipertensiva
4.
J Sleep Res ; 32(3): e13776, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36351660

RESUMEN

Nightmares are considerably prevalent in the general population and are known to be closely associated with a variety of mental disorders. However, not much is known about the immediate antecedents and consequences of nightmares. Therefore, we used intensive longitudinal assessments to investigate the night-to-night within-person associations between nightmares on the one hand and fear of sleep, somatic as well as cognitive pre-sleep arousal, and sleep quality on the other hand. Young women with regular nightmares (n = 16) maintained a sleep diary for around 30 days; upon awaking, the participants reported on nightmares and sleep quality during the past night as well as the pre-sleep levels of arousal and fear of sleep (which resulted in 461 observations). Participants also wore an actigraph, which provided objective sleep parameters. Multilevel modeling showed that higher levels of fear of sleep and lower subjective sleep quality were significantly associated with higher levels of nightmare distress. Furthermore, we found individual differences in the strength of these associations, which implies that factors proximate to nightmares may vary across individuals. Pre-sleep arousal, however, did not show expected within-person associations with nightmares or fear of sleep. These findings highlight the crucial role of fear of sleep in the etiology of nightmares and sleep disturbances, while pointing to the importance of pursuing individual, personalised models that explain heterogeneity in the process of triggering nightmares.


Asunto(s)
Sueños , Trastornos del Sueño-Vigilia , Humanos , Femenino , Sueños/psicología , Estudios Longitudinales , Sueño , Trastornos del Sueño-Vigilia/psicología , Miedo
5.
BMC Psychiatry ; 23(1): 455, 2023 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-37344778

RESUMEN

BACKGROUND: In a parallel randomized controlled trial the effectiveness of the family- and group-based cognitive-behavioural "Gug-Auf" intervention in preventing depression in children of depressed parents was evaluated. We hypothesized that the intervention would be associated with reduced incidence of depression at 15 months as well as with reduced symptom severity at 6, 9, and 15 months. We also explored the role of a number of mediators and moderators. METHODS: Families were included if a parent (n = 100, mean age = 46.06, 61% female) had experienced depression and children (n = 135, aged 8-17 years, 53% female) had no mental illness. Families (91.5% German) were randomly allocated (50:50 block-wise; stratified by child age and parental depression) to the 12-session "GuG-Auf" intervention or no intervention. Outcomes were assessed (on an intention-to-treat basis) at 0-(T1), 6-(T2), 9-(T3) and 15-months (T4) after baseline. Primary outcome (onset of depression; T4) was assessed with standardized (blinded) clinical interviews. Secondary (unblinded) outcome was risk of depression (at T2-T4) indicated by self- and parent-reported symptoms of internalizing, externalizing and depressive disorder. Potential mediators were emotion regulation, attributional style, knowledge of depression and parenting style. Potential moderators were parental depression severity and negative life events. RESULTS: None of the children who received the intervention developed depression, whereas two of those in the control group did. The intervention significantly reduced depression risk (indicated by severity of self-reported internalizing symptoms) at T3 (p = .027, d = -0.45) and T4 (p = .035, d = -0.44). Both groups showed reduced depressive symptoms (p = .029, d = -0.44). Cognitive problem-solving and negative parenting emerged as mediators. There was no evidence that the intervention was associated with parent-reported internalizing symptoms or externalizing symptoms. No adverse events were observed. CONCLUSIONS: Children of parents with depression showed an increase in self-reported (but not parent-reported) internalizing symptoms over time. This increase was not present in children who received the GuG-Auf intervention. The intervention was not associated with changes in externalizing symptoms. Conclusions regarding prevention of the onset of depression were not possible. Despite some limitations in the generalizability, these findings contribute to reducing the burden of youth depression. REGISTRATION: The trial was registered on 16/04/2014 at ClinicalTrials.gov ( NCT02115880 ) and study protocol published in BMC Psychiatry ( https://bmcpsychiatry.biomedcentral.com/articles/10.1186/s12888-014-0263-2 ).


Asunto(s)
Hijo de Padres Discapacitados , Depresión , Adolescente , Humanos , Niño , Femenino , Persona de Mediana Edad , Masculino , Depresión/prevención & control , Depresión/psicología , Padres/psicología , Responsabilidad Parental/psicología , Hijo de Padres Discapacitados/psicología , Conducta Infantil
6.
BMC Nephrol ; 24(1): 68, 2023 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-36949416

RESUMEN

BACKGROUND: Hypertensive emergency is a critical disease that causes multifaceted sequelae, including end-stage kidney disease and cardiovascular disease. Although the renin-angiotensin-aldosterone (RAA) system is enormously activated in this disease, there are few reports that attempt to characterize the effect of early use of RAA inhibitors (RASi) on the temporal course of kidney function. METHODS: This retrospective cohort study was conducted to clarify whether the early use of RASi during hospitalization offered more favorable benefits on short-term renal function and long-term renal outcomes in patients with hypertensive emergencies. We enrolled a total of 49 patients who visited our medical center with acute severe hypertension and multiple organ dysfunction between April 2012 and August 2020. Upon admission, the patients were treated with intravenous followed by oral antihypertensive drugs, including RASi and Ca channel blockers (CCB). Kidney function as well as other laboratory and clinical parameters were compared between RASi-treated and CCB- treated group over 2 years. RESULTS: Antihypertensive treatment effectively reduced blood pressure from 222 ± 28/142 ± 21 to 141 ± 18/87 ± 14 mmHg at 2 weeks and eGFR was gradually restored from 33.2 ± 23.3 to 40.4 ± 22.5 mL/min/1.73m2 at 1 year. The renal effect of antihypertensive drugs was particularly conspicuous when RASi was started in combination with other conventional antihypertensive drugs at the early period of hospitalization (2nd day [IQR: 1-5.5]) and even in patients with moderately to severely diminished eGFR (< 30 mL/min/1.73 m2) on admission. In contrast, CCB modestly restored eGFR during the observation period. Furthermore, renal survival probabilities were progressively deteriorated in patients who had manifested reduced eGFR (< 15 mL/min/1.73 m2) or massive proteinuria (urine protein/creatinine ≥ 3.5 g/gCr) on admission. Early use of RASi was associated with a favorable 2-year renal survival probability (0.90 [95%CI: 0.77-1.0] vs. 0.63 [95%CI: 0.34-0.92] for RASi ( +) and RASi (-), respectively, p = 0.036) whereas no apparent difference in renal survival was noted for CCB. CONCLUSIONS: Early use of RASi contributes to the renal functional recovery from acute reduction in eGFR among patients with hypertensive emergencies. Furthermore, RASi offers more favorable effect on 2-year renal survival, compared with CCB.


Asunto(s)
Antihipertensivos , Hipertensión , Humanos , Antihipertensivos/farmacología , Renina , Inhibidores de la Enzima Convertidora de Angiotensina/efectos adversos , Angiotensinas/farmacología , Angiotensinas/uso terapéutico , Estudios Retrospectivos , Urgencias Médicas , Riñón , Sistema Renina-Angiotensina , Hipertensión/complicaciones
7.
J Emerg Med ; 63(2): 240-246, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35871989

RESUMEN

BACKGROUND: Current guidelines emphasize the assistance of the emergency dispatcher in bystander cardiopulmonary resusitation (CPR). Its quality, however, has varied across cases. OBJECTIVE: To determine the effect of repetitive coaching by dispatchers using verbal encouragement on the quality of lay-rescuer CPR. METHODS: We conducted a dispatch-assisted CPR (DACPR) simulation study. Participants with no CPR training within the previous year were assigned randomly to 1 of 2 DACPR simulations. One was the No Coaching Group: callers were told to perform CPR and the dispatcher periodically confirmed that the caller was performing CPR. The second group was the Coaching Group: the dispatcher repetitively coached, encouraged, and counted aloud using a metronome. Participants performed CPR for 2 min under instruction from the study dispatcher. Parameters including chest compression depth, rate, and chest compression fraction were recorded by video camera and CPR manikin. RESULTS: Forty-nine participants 20 to 50 years of age were recruited, and 48 completed the simulation (Coaching Group, n = 27; No Coaching Group, n = 21). The chest compression fraction was higher in the Coaching Group (99.4% vs. 93.0%, p = 0.005) and no participants interrupted chest compression more than 10 s in this group. When comparing the average depth of each 30-s period in each group, the depth increased over time in the Coaching Group (40.9 mm, 43.9 mm, 44.1 mm, and 42.8 mm), while it slightly decreased in the No Coaching Group (40.6 mm, 40.1 mm, 39.4 mm, and 39.8 mm). CONCLUSIONS: Repetitive verbal encouragements augmented chest compression depth with less-hands off time. Continuous coaching by dispatchers can optimize lay-rescuer CPR. © 2022 Elsevier Inc.


Asunto(s)
Reanimación Cardiopulmonar , Paro Cardíaco Extrahospitalario , Sistemas de Comunicación entre Servicios de Urgencia , Humanos , Maniquíes , Paro Cardíaco Extrahospitalario/terapia , Presión
8.
Air Med J ; 41(4): 391-395, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35750447

RESUMEN

OBJECTIVE: Few studies have evaluated the effects of helicopter emergency medical services (HEMS) alone. This single-center study compared the changes in vital signs during ground emergency medical services (GEMS), HEMS, and hospital interventions to assess the impact of HEMS interventions. METHODS: This retrospective observational study included 168 trauma patients older than 18 years of age who received HEMS. Patients with cardiac arrest or those who received medical attention before HEMS were excluded. We assessed 3 intervention phases (GEMS, HEMS, and hospital). The changes in heart rate, systolic blood pressure, respiratory rate, and shock index in response to interventions were calculated and divided by the intervention time, and the changes observed during the interventions were compared. RESULTS: No changes in vital signs were observed when receiving GEMS. Systolic blood pressure increased and shock index decreased after HEMS, whereas systolic blood pressure decreased and shock index increased during hospital interventions. Heart rate showed no significant change (P = .12), and respiratory rate showed very little change. Systolic blood pressure increased significantly during HEMS compared with the pre- and postintervention periods. CONCLUSION: Changes in vital signs differed according to the intervention. Systolic blood pressure increased during HEMS but not with GEMS or hospital interventions.


Asunto(s)
Ambulancias Aéreas , Servicios Médicos de Urgencia , Aeronaves , Frecuencia Cardíaca , Hospitales , Humanos , Puntaje de Gravedad del Traumatismo , Estudios Retrospectivos
9.
BMC Psychiatry ; 21(1): 540, 2021 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-34717567

RESUMEN

BACKGROUND: Mental disorders are prevalent and cause considerable burden of disease. Exercise has been shown to be efficacious to treat major depressive disorders, insomnia, panic disorder with and without agoraphobia and post traumatic stress disorder (PTSD). METHODS: This pragmatic, two arm, multi-site randomised controlled trial will evaluate the efficacy and cost-effectiveness of the manualized, group-based six-months exercise intervention "ImPuls", among physically inactive patients with major depressive disorders, insomnia, panic disorder, agoraphobia and PTSD within a naturalistic outpatient context in Germany. A minimum of 375 eligible outpatients from 10 different study sites will be block-randomized to either ImPuls in addition to treatment as usual (TAU) or TAU only. ImPuls will be conducted by trained exercise therapists and delivered in groups of six patients. The program will combine (a) moderate to vigorous aerobic exercise carried out two-three times a week for at least 30 min with (b) behavior change techniques for sustained exercise behavior change. All outcomes will be assessed pre-treatment, post-treatment (six months after randomization) and at follow-up (12 months after randomization). Primary outcome will be self-reported global symptom severity assessed with the Brief Symptom Inventory (BSI-18). Secondary outcomes will be accelerometry-based moderate to vigorous physical activity, self-reported exercise, disorder-specific symptoms, quality-adjusted life years (QALY) and healthcare costs. Intention-to-treat analyses will be conducted using mixed models. Cost-effectiveness and cost-utility analysis will be conducted using incremental cost-effectiveness and cost-utility ratios. DISCUSSION: Despite its promising therapeutic effects, exercise programs are currently not provided within the outpatient mental health care system in Germany. This trial will inform service providers and policy makers about the efficacy and cost-effectiveness of the group-based exercise intervention ImPuls within a naturalistic outpatient health care setting. Group-based exercise interventions might provide an option to close the treatment gap within outpatient mental health care settings. TRIAL REGISTRATION: The study was registered in the German Clinical Trials Register (ID: DRKS00024152 , 05/02/2021).


Asunto(s)
Trastorno Depresivo Mayor , Agorafobia , Análisis Costo-Beneficio , Terapia por Ejercicio , Humanos , Estudios Multicéntricos como Asunto , Ensayos Clínicos Pragmáticos como Asunto , Años de Vida Ajustados por Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto
10.
Memory ; 29(1): 1-10, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33135956

RESUMEN

This investigation examined conflicting suggestions regarding the association between problems retrieving specific autobiographical memories and the tendency to retrieve the details of these memories. We also examined whether these tendencies are differentially related to depression symptoms. U.S., Belgian, Hong Kong and Japanese participants retrieved memories related to cue words. Responses were coded for if they referred to a specific event (i.e., an event lasting less than 24 h) and their details (What? Where? Who?). Across sites, and in meta-analyses, the retrieval of more specific memories was associated with retrieval of more details. Memories that were specific included more detail than non-specific memories. Across sites, retrieval of more specific memories and more detail was associated with less severe depression symptoms. Episodic specificity and detailedness are related but separable constructs. Future investigations of autobiographical memory specificity, and methods for alleviating problematic specificity, should consider measures of episodic detailedness.


Asunto(s)
Trastorno Depresivo , Memoria Episódica , Humanos , Recuerdo Mental
11.
Multivariate Behav Res ; 56(5): 768-786, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32431169

RESUMEN

Dynamical interplays in emotions have been investigated using vector autoregressive (VAR) models, whose estimates can be used to cluster participants into unknown groups. The present study evaluated a clustering algorithm, the alternating least square (ALS) algorithm, for accuracy in predicting individual group membership. We systematically manipulated (a) the number of variables in a model, (b) the size of group differences in regression coefficients, and (c) the number of regression coefficients that vary across the groups (i.e., effective features). The ALS algorithm works reliably when there are at least 5 effective features with very large group differences in a 5-variable model; and 9 effective features with very large group differences in a 10-variable model. These findings suggest that the ALS algorithm is sensitive to group differences that are present only in several coefficients of a VAR model, but that the group differences have to be large. We also found that the ALS algorithm outperforms another clustering method, Gaussian mixture modeling. The ALS algorithm was further evaluated with unbalanced sample sizes between groups and with a greater number of groups in data (Study 2). A real data application was provided to illustrate how to interpret the detected group differences (Study 3).


Asunto(s)
Algoritmos , Emociones , Análisis por Conglomerados , Humanos , Análisis de los Mínimos Cuadrados , Distribución Normal
12.
Cancer ; 126(18): 4246-4255, 2020 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-32639592

RESUMEN

BACKGROUND: Many breast cancer survivors suffer from cognitive complaints after cancer treatment, affecting their quality of life. The objective of this pilot study was to investigate the effect of a blended-care mindfulness-based intervention (MBI) on chemotherapy-related cognitive impairment and functional brain changes. Furthermore, correlations between changes in cognitive functioning and self-reported behavioral factors were investigated. METHODS: Breast cancer survivors (n = 33) who reported cognitive impairment were randomly allocated to a mindfulness condition (n = 18) or a waitlist control condition (n = 15). Patients completed questionnaires on cognitive impairment, emotional distress, and fatigue; neuropsychological tests; and resting-state functional magnetic resonance imaging before the start of MBI (time 1 [T1]), immediately after the completion of an 8-week MBI program (T2), and 3 months postintervention (T3). Resting-state functional connectivity was estimated in the default mode network, the dorsal and salience attention networks, and the frontoparietal network. Mixed model repeated-measures analysis was performed to test the intervention effect. RESULTS: Patients in the mindfulness condition exhibited significantly higher connectivity between the dorsal and salience attention networks after the mindfulness intervention compared with those in the control condition. MBI participants also had reduced subjective cognitive impairment, emotional distress, and fatigue. No intervention effect was observed on neurocognitive tests. CONCLUSIONS: MBI may induce functional brain changes in networks related to attention and may have a positive effect on subjective measures of cognitive impairment in breast cancer survivors. Therefore, MBI could be a suitable intervention to improve quality of life in this population and deserves further study in this context.


Asunto(s)
Disfunción Cognitiva/psicología , Imagen por Resonancia Magnética/métodos , Atención Plena/métodos , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Adulto Joven
13.
Opt Express ; 28(1): 607-625, 2020 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-32118985

RESUMEN

In this work, shape-dependent mid-infrared properties of novel split ring resonator (SRR) metamaterials composed of single-walled carbon nanotube (CNT) forest are investigated. The introduction of the gap and dip shape to the closed ring geometry reduced the total reflectance by 15%, due to the generation of circular currents and LC resonances in SRRs. The increase of the SRR height reduced the total IR reflectance by 25%. Unique one-dimensional anisotropic electric and photonic properties of CNTs, combined with an artificial refractive index induced in SRR circuits, will stimulate the development of new optoelectronics applications.

14.
J Sleep Res ; 29(1): e12938, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31638298

RESUMEN

Cognitive models of insomnia highlight the role of biased cognition in sleep-related information, which is proposed to underlie pre-sleep worry, which in turn results in both subjective and objective sleep deficits. To test this hypothesis, the current study investigated interpretational bias, which is a tendency to interpret ambiguous stimuli in a threat-related (here: insomnia-related) manner. We specifically hypothesized that interpretational bias would be associated with (a) pre-sleep worry and (b) poor subjective and objective sleep. Interpretational bias was measured using the ambiguous scenario task, in which participants (n = 76, community sample) were presented with two types of scenarios (insomnia and anxiety related) that could be alternatively interpreted in a neutral manner. Participants additionally completed questionnaires to assess global sleep quality and pre-sleep worry, which were followed by 1-week sleep assessments (via diaries and actigraphy) to estimate specific, daily subjective and objective sleep parameters. The results showed that insomnia-related (but not anxiety-related) interpretational bias was positively associated with pre-sleep worry as well as overall sleep quality. However, these associations could be explained by general trait anxiety. We also found no connection to specific subjective or objective parameters of daily sleep, such as sleep onset latency. These findings support the cognitive-hyperarousal mechanism, where biased cognition (together with trait anxiety) underlies pre-sleep worry. The association with overall sleep quality, but not with specific, daily subjective or objective sleep parameters, may suggest that interpretational bias is specifically relevant for how individuals judge and describe their sleep quality.


Asunto(s)
Actigrafía/métodos , Ansiedad/etiología , Trastornos del Inicio y del Mantenimiento del Sueño/complicaciones , Adolescente , Adulto , Ansiedad/psicología , Sesgo , Femenino , Humanos , Masculino , Trastornos del Inicio y del Mantenimiento del Sueño/psicología , Adulto Joven
15.
Behav Sleep Med ; 17(5): 586-594, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-29424553

RESUMEN

Objective/Background: Sleep can have an important influence on memory. However, it is unclear whether there is any relation between sleep quality and the specificity with which autobiographical memories are retrieved, a key factor associated with vulnerability for, and the presence of, depression and other psychiatric diagnoses. The present study provides the first investigation of the association between sleep quality and autobiographical memory specificity. Participants and Method: Fifty-four unselected community participants completed the Autobiographical Memory Test (AMT) to assess memory specificity, while subjective and objective measures of total sleep time and sleep onset latency were provided through a daily diary and an actigraphy wristwatch worn for a week. Participants also completed questionnaires that measure known correlates of AMT specificity: the Ruminative Response Scale (RRS) and Beck Depression Inventory (BDI-II). Results: Shorter sleep duration, measured using actigraphy, was associated with reduced autobiographical memory specificity. There was no evidence of an association between total sleep time recorded by self-report diaries, or of sleep onset latency recorded using actigraphy or diaries and memory specificity. The relation between actigraphy-assessed total sleep time and memory specificity was independent of the effects of rumination or depressive symptoms on these variables. Conclusions: Shorter sleep duration is associated with reduced memory specificity. Future research examining memory specificity and its association with psychopathology should consider the role of sleep quality around the time of memory recall in specificity.


Asunto(s)
Actigrafía/métodos , Memoria Episódica , Trastornos del Sueño-Vigilia/complicaciones , Adulto , Femenino , Humanos , Masculino , Encuestas y Cuestionarios , Adulto Joven
16.
Memory ; 27(3): 306-313, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30081736

RESUMEN

The Autobiographical Memory Test (AMT) has been central in psychopathological studies of memory dysfunctions, as reduced memory specificity or overgeneralised autobiographical memory has been recognised as a hallmark vulnerability for depression. In the AMT, participants are asked to generate specific memories in response to emotional cue words, and their responses are scored by human experts. Because the manual coding takes some time, particularly when analysing a large dataset, recent studies have proposed computerised scoring algorithms. These algorithms have been shown to reliably discriminate between specific and non-specific memories of English-speaking children and Dutch- and Japanese-speaking adults. The key limitation is that the algorithm is not developed for English-speaking adult memories, which may cover a wider range of vocabulary that the existing algorithm for English-speaking child memories cannot process correctly. In the present study, we trained a new support vector machine to score memories of English-speaking adults. In a performance test (predicting memory specificity against human expert coding), the adult-memory algorithm outperformed the child-memory variant. In another independent performance test, the adult-memory algorithm showed robust performances to score memories that were generated in response to a different set of cues. These results suggest that the adult-memory algorithm reliably scores memory specificity.


Asunto(s)
Algoritmos , Emociones/fisiología , Aprendizaje Automático , Memoria Episódica , Recuerdo Mental/fisiología , Adulto , Cognición , Señales (Psicología) , Femenino , Humanos , Masculino , Estados Unidos
17.
J Med Internet Res ; 21(5): e13333, 2019 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-31094362

RESUMEN

BACKGROUND: The ability to retrieve specific autobiographical memories decreases with cognitive aging. This decline is clinically relevant due to its association with impairments in problem solving, daily functioning, and depression. A therapist-delivered group training protocol, Memory Specificity Training (MeST), has been shown to enhance the retrieval of specific memories while ameliorating the impairments and negative outcomes associated with reduced specificity. The therapist-delivered nature of this intervention means it is relatively expensive to deliver and difficult for people with mobility impairments, such as older people, to receive. OBJECTIVE: The objective of this study was to test if a novel, Web-based computerized version of a group training protocol called Memory Specificity Training, has the potential to increase autobiographical memory specificity and impact associated secondary psychological processes. METHODS: A total of 21 participants (13 female; mean age 67.05, SD 6.55) who experienced a deficit in retrieving specific autobiographical memory were trained with c-MeST. We assessed memory specificity at preintervention and postintervention, as well as secondary processes such as depressive symptoms, rumination, and problem-solving skills. RESULTS: Memory specificity increased significantly after participants completed c-MeST (r=.57). Session-to-session scores indicated that autobiographical memory specificity improved most from the online baseline assessment to the first Web-based session. Symptoms or secondary processes such as problem-solving skills did not change significantly. CONCLUSIONS: A Web-based automated individual version of MeST is a feasible, low-cost intervention for reduced memory specificity in healthy older adults. Future studies should clarify the preventive impact of c-MeST in other at-risk sample populations with longer follow-up times.


Asunto(s)
Estudios Controlados Antes y Después/métodos , Memoria Episódica , Anciano , Envejecimiento , Femenino , Voluntarios Sanos , Humanos , Masculino
18.
Opt Lett ; 43(8): 1658-1661, 2018 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-29652333

RESUMEN

Substantial enhancement of terahertz magnetic near field achieved by the combination of a tapered metallic waveguide and a micro-split-ring resonator is demonstrated. The magnetic near field is probed directly via the magneto-optic sampling with a Tb3Ga5O12 crystal. The incident terahertz wave with a half-cycle waveform is generated by using the pulse-front tilting method. The magnetic near field at the resonant frequency is enhanced by more than 30 times through the combination of the waveguide and the resonator. The peak amplitude of the magnetic field with a damped oscillation waveform in the time domain is up to 0.4 T. The resonant frequency can be tuned by adopting different resonator designs. The mechanism of the enhancement is analyzed by performing calculations based on the finite element method. The strong terahertz magnetic near field enables the excitation of large-amplitude spin dynamics and can be utilized for an ultrafast spin control.

19.
Cogn Emot ; 32(3): 658-665, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-28361569

RESUMEN

The underlying mechanisms of the effectiveness of mindfulness-based interventions for emotional well-being remain poorly understood. Here, we examined the potential mediating effects of cognitive reactivity and self-compassion on symptoms of depression, anxiety and stress using data from an earlier randomised controlled school trial. A moderated time-lagged mediation model based on multilevel modelling was used to analyse the data. The findings showed that post-treatment changes in cognitive reactivity and self-coldness, an aspect of self-compassion, mediated subsequent changes in symptoms of depression, anxiety and stress. These results suggest that cognitive reactivity and self-coldness may be considered as transdiagnostic mechanisms of change of a mindfulness-based intervention programme for youth.


Asunto(s)
Cognición , Empatía , Trastornos Mentales/terapia , Atención Plena/métodos , Servicios de Salud Escolar , Autoimagen , Adolescente , Trastornos de Ansiedad/psicología , Trastornos de Ansiedad/terapia , Trastorno Depresivo/psicología , Trastorno Depresivo/terapia , Femenino , Humanos , Masculino , Trastornos Mentales/psicología , Evaluación de Programas y Proyectos de Salud/métodos , Estrés Psicológico/psicología , Estrés Psicológico/terapia , Resultado del Tratamiento
20.
Behav Res Methods ; 49(3): 835-852, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-27338931

RESUMEN

In the present study, we explored the linguistic nature of specific memories generated with the Autobiographical Memory Test (AMT) by developing a computerized classifier that distinguishes between specific and nonspecific memories. The AMT is regarded as one of the most important assessment tools to study memory dysfunctions (e.g., difficulty recalling the specific details of memories) in psychopathology. In Study 1, we utilized the Japanese corpus data of 12,400 cue-recalled memories tagged with observer-rated specificity. We extracted linguistic features of particular relevance to memory specificity, such as past tense, negation, and adverbial words and phrases pertaining to time and location. On the basis of these features, a support vector machine (SVM) was trained to classify the memories into specific and nonspecific categories, which achieved an area under the curve (AUC) of .92 in a performance test. In Study 2, the trained SVM was tested in terms of its robustness in classifying novel memories (n = 8,478) that were retrieved in response to cue words that were different from those used in Study 1. The SVM showed an AUC of .89 in classifying the new memories. In Study 3, we extended the binary SVM to a five-class classification of the AMT, which achieved 64%-65% classification accuracy, against the chance level (20%) in the performance tests. Our data suggest that memory specificity can be identified with a relatively small number of words, capturing the universal linguistic features of memory specificity across memories in diverse contents.


Asunto(s)
Lingüística , Memoria Episódica , Máquina de Vectores de Soporte , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Adulto Joven
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA