Depression and cardiac dysautonomia in eating disorders.

PubMed

Jelinek, Herbert F; Spence, Ian; Cornforth, David J; Tarvainen, Mika P; Russell, Janice

2018-06-01

Individuals with eating disorder (ED) are at an increased risk of cardiac arrhythmias due to cardiac dysautonomia, which may be exacerbated if depression is also present. The aim of the study was to use heart rate analysis as a marker for cardiac dysautonomia in patients with eating disorders and depression as a comorbidity. Clinical data, including presence of depression, was obtained from all participants. A three-lead ECG was used to determine interbeat intervals, and these were analyzed using time domain, frequency domain, and nonlinear heart rate variability measures. Thirty ED patients and 44 healthy controls participated in the research. The presence of depression was associated with additional decreased time domain (RMSSD 36.8 ± 26 vs. 22.9 ± 12.3; p < 0.05), frequency domain (HF power 788 ± 1075 vs. 279 ± 261; p < 0.05), and nonlinear domain (DFAα 2 0.82 ± 0.1 vs. 0.97 ± 0.1; p < 0.01) which results in the ED group compared to patients with no depression. The presence of depression in ED patients decreased HRV even further compared to the non-depressed patient group and controls, suggesting that higher vigilance and a holistic treatment approach may be required for these patients to avoid cardiac arrhythmia complications.

Associations between loneliness, depressive symptoms and perceived togetherness in older people.

PubMed

Tiikkainen, P; Heikkinen, R-L

2005-11-01

This study explores the associations of loneliness with depressive symptoms in a five-year follow-up and describes how the six dimensions of perceived togetherness explain loneliness and depressive symptoms at baseline. The data were collected on 207 residents of Jyväskylä, central Finland, who at baseline in 1990 were aged 80; and 133 residents who at follow-up in 1995 were aged 85. Loneliness was assessed using a questionnaire item with four preset response options, perceived togetherness using the Social Provisions Scale, and depressive symptoms using the CES-D scale. A recursive structural equation model showed that in women but not in men, depressive symptoms predicted more experiences of loneliness. Those who were lonely were more depressed (CES-D score 16 or over) and experienced less togetherness than those who were not. Loneliness was explained by reliable alliance, social integration and attachment; and depressive symptoms were explained by guidance, reassurance of worth, reliable alliance and attachment. A common feature in both loneliness and depressive symptoms was a lower level of perceived emotional togetherness in social interaction.

The impact of stress systems and lifestyle on dyslipidemia and obesity in anxiety and depression.

PubMed

van Reedt Dortland, Arianne K B; Vreeburg, Sophie A; Giltay, Erik J; Licht, Carmilla M M; Vogelzangs, Nicole; van Veen, Tineke; de Geus, Eco J C; Penninx, Brenda W J H; Zitman, Frans G

2013-02-01

Dyslipidemia and obesity have been observed in persons with severe anxiety or depression, and in tricyclic antidepressant (TCA) users. This likely contributes to the higher risk of cardiovascular disease (CVD) in anxiety and depressive disorders. We aimed to elucidate whether biological stress systems or lifestyle factors underlie these associations. If so, they may be useful targets for CVD prevention and intervention. Within 2850 Netherlands Study of Depression and Anxiety (NESDA) participants, we evaluated the explaining impact of biological stress systems (i.e., the hypothalamic-pituitary-adrenal [HPA] axis, autonomic nervous system [ANS] and inflammation) and lifestyle factors (i.e., tobacco and alcohol use, and physical activity) on adverse associations of anxiety and depression severity and TCA use with high and low-density lipoprotein cholesterol, triglycerides, body mass index and waist circumference. Through linear regression analyses, percentual change (%Δ) in β was determined and considered significant when %Δ>10. The inflammatory marker C-reactive protein had the most consistent impact (explaining 14-53% of the associations of anxiety and depression severity and TCA use with lipid and obesity levels), followed by tobacco use (explaining 34-43% of the associations with lipids). The ANS mediated all associations with TCA use (explaining 32-61%). The HPA axis measures did not explain any of the associations. Increased dyslipidemia and (abdominal) obesity risk in patients with more severe anxiety disorders and depression may be partly explained by chronic low-grade inflammation and smoking. TCAs may increase metabolic risk through enhanced sympathetic and decreased parasympathetic ANS activity. That the HPA axis had no impact in our sample may reflect the possibility that the HPA axis only plays a role in acute stress situations rather than under basal conditions. Copyright © 2012 Elsevier Ltd. All rights reserved.

The influences of perceived social support and personality on trajectories of subsequent depressive symptoms in Taiwanese youth.

PubMed

Lien, Yin-Ju; Hu, Jhih-Ning; Chen, Chia-Yi

2016-03-01

Little is known about the combined effect of personality and social support on trajectories of depressive symptoms among youth. This study aims to investigate the influence of social support in different contexts on the development of depressive symptoms during adolescence and whether the association is moderated by adolescents' personality. The data using in this study is selected from the Taiwan Educational Panel Survey (TEPS), a longitudinal panel study since the year 2000 (at age 13) and three more waves (at ages 15, 17, and 18). A total of four waves of students' data (N = 4163) are analyzed using the latent growth models. The results indicate that the depressive symptom trajectory of Taiwan adolescents gradually grows in a quadratic curve. Social support in family context rather than school context was associated with depressive symptoms, while only a positive association is found between maternal support and depressive symptoms at the start. Meanwhile, increased extroversion personality is associated with the decreased initial level, increased linear changes, and decreased non-linear quadratic changes of adolescents' depressive symptoms. Further analyses show that a significant interaction between maternal support and extroversion personality is associated with increased non-linear quadratic growth curve of adolescents' depressive symptoms. In conclusion, adolescents' extroversion personality might moderate the effect of maternal support on developmental trajectory of depressive symptoms. Intervention that improves social support should take account for adolescent's personality, which may alter trajectory of psychological distress during adolescence. Copyright © 2016 Elsevier Ltd. All rights reserved.

Suicidal ideation, depression, and conduct disorder in a sample of adolescent and young adult twins

PubMed Central

Linker, Julie; Gillespie, Nathan A; Maes, Hermine; Eaves, Lindon; Silberg, Judy L.

2012-01-01

Background The co-occurrence of suicidal ideation, depression, and conduct disturbance is likely explained in part by correlated genetic and environmental risk factors. Little is known about the specific nature of these associations. Method Structured interviews on 2814 twins from the Virginia Twin Study of Adolescent Behavioral Development (VTSABD) and young adult follow-up (YAFU) yielded data on symptoms of depression, conduct disorder and adolescent and young adult suicidal ideation. Results Univariate analyses revealed that the familial aggregation for each trait was explained by a combination of additive genetic and shared environmental effects. Suicidal ideation in adolescence was explained in part by genetic influences, but predominantly accounted for by environmental factors. A mixture of genetic and shared environmental influences explained ideation occurring in young adulthood. Multivariate analyses revealed that there are genetic and shared environmental effects common to suicidal ideation, depression, and conduct disorder. The association between adolescent suicidal ideation and CD was attributable to the same genetic and environmental risk factors for depression. Conclusions These findings underscore that prevention and intervention strategies should reflect the different underlying mechanisms involving depression and conduct disorder to assist in identifying adolescents at suicidal risk. PMID:22646517

Suicidal ideation, depression, and conduct disorder in a sample of adolescent and young adult twins.

PubMed

Linker, Julie; Gillespie, Nathan A; Maes, Hermine; Eaves, Lindon; Silberg, Judy L

2012-08-01

The co-occurrence of suicidal ideation, depression, and conduct disturbance is likely explained in part by correlated genetic and environmental risk factors. Little is known about the specific nature of these associations. Structured interviews on 2,814 twins from the Virginia Twin Study of Adolescent Behavioral Development (VTSABD) and Young Adult Follow-Up (YAFU) yielded data on symptoms of depression, conduct disorder, and adolescent and young adult suicidal ideation. Univariate analyses revealed that the familial aggregation for each trait was explained by a combination of additive genetic and shared environmental effects. Suicidal ideation in adolescence was explained in part by genetic influences, but predominantly accounted for by environmental factors. A mixture of genetic and shared environmental influences explained ideation occurring in young adulthood. Multivariate analyses revealed that there are genetic and shared environmental effects common to suicidal ideation, depression, and conduct disorder. The association between adolescent suicidal ideation and CD was attributable to the same genetic and environmental risk factors for depression. These findings underscore that prevention and intervention strategies should reflect the different underlying mechanisms involving depression and conduct disorder to assist in identifying adolescents at suicidal risk. © 2012 The American Association of Suicidology.

Explaining ecological clusters of maternal depression in South Western Sydney.

PubMed

Eastwood ED, John; Kemp, Lynn; Jalaludin, Bin

2014-01-24

The aim of the qualitative study reported here was to: 1) explain the observed clustering of postnatal depressive symptoms in South Western Sydney; and 2) identify group-level mechanisms that would add to our understanding of the social determinants of maternal depression. Critical realism provided the methodological underpinning for the study. The setting was four local government areas in South Western Sydney, Australia. Child and Family practitioners and mothers in naturally occurring mothers groups were interviewed. Using an open coding approach to maximise emergence of patterns and relationships we have identified seven theoretical concepts that might explain the observed spatial clustering of maternal depression. The theoretical concepts identified were: Community-level social networks; Social Capital and Social Cohesion; "Depressed community"; Access to services at the group level; Ethnic segregation and diversity; Supportive social policy; and Big business. We postulate that these regional structural, economic, social and cultural mechanisms partially explain the pattern of maternal depression observed in families and communities within South Western Sydney. We further observe that powerful global economic and political forces are having an impact on the local situation. The challenge for policy and practice is to support mothers and their families within this adverse regional and global-economic context.

Short-term depression and transient memory in sensory cortex.

PubMed

Gillary, Grant; Heydt, Rüdiger von der; Niebur, Ernst

2017-12-01

Persistent neuronal activity is usually studied in the context of short-term memory localized in central cortical areas. Recent studies show that early sensory areas also can have persistent representations of stimuli which emerge quickly (over tens of milliseconds) and decay slowly (over seconds). Traditional positive feedback models cannot explain sensory persistence for at least two reasons: (i) They show attractor dynamics, with transient perturbations resulting in a quasi-permanent change of system state, whereas sensory systems return to the original state after a transient. (ii) As we show, those positive feedback models which decay to baseline lose their persistence when their recurrent connections are subject to short-term depression, a common property of excitatory connections in early sensory areas. Dual time constant network behavior has also been implemented by nonlinear afferents producing a large transient input followed by much smaller steady state input. We show that such networks require unphysiologically large onset transients to produce the rise and decay observed in sensory areas. Our study explores how memory and persistence can be implemented in another model class, derivative feedback networks. We show that these networks can operate with two vastly different time courses, changing their state quickly when new information is coming in but retaining it for a long time, and that these capabilities are robust to short-term depression. Specifically, derivative feedback networks with short-term depression that acts differentially on positive and negative feedback projections are capable of dynamically changing their time constant, thus allowing fast onset and slow decay of responses without requiring unrealistically large input transients.

Pathways from education to depression.

PubMed

Lee, Jinkook

2011-06-01

We examine educational gradients in depression and identify underlying mechanisms of how education might affect depression. We use a nationally representative sample of community-residing adults aged 45 and older from the 2006 Korean Longitudinal Study of Aging, which collected information about depressive symptoms and education. Using tobit regression, we estimate the effect of education on depression and examine what can explain the education gradients by controlling for proxy variables of different pathways linking education to depression. We found cognitive ability, economic resources, social status, social network, and health behavior explain all of the education gradients. Education affects depression through different underlying mechanisms, and the single most important pathway is through developing cognitive ability. Through these pathways, educational attainment influences not only depression for an individual but also for one's spouse, particularly for women, and parents.

Sociodemographic, perceived and objective need indicators of mental health treatment use and treatment-seeking intentions among primary care medical patients.

PubMed

Elhai, Jon D; Voorhees, Summer; Ford, Julian D; Min, Kyeong Sam; Frueh, B Christopher

2009-01-30

We explored sociodemographic and illness/need associations with both recent mental healthcare utilization intensity and self-reported behavioral intentions to seek treatment. Data were examined from a community sample of 201 participants presenting for medical appointments at a Midwestern U.S. primary care clinic, in a cross-sectional survey study. Using non-linear regression analyses accounting for the excess of zero values in treatment visit counts, we found that both sociodemographic and illness/need models were significantly predictive of both recent treatment utilization intensity and intentions to seek treatment. Need models added substantial variance in prediction, above and beyond sociodemographic models. Variables with the greatest predictive role in explaining past treatment utilization intensity were greater depression severity, perceived need for treatment, older age, and lower income. Robust variables in predicting intentions to seek treatment were greater depression severity, perceived need for treatment, and more positive treatment attitudes. This study extends research findings on mental health treatment utilization, specifically addressing medical patients and using statistical methods appropriate to examining treatment visit counts, and demonstrates the importance of both objective and subjective illness/need variables in predicting recent service use intensity and intended future utilization.

Comorbidities, medications and depressive symptoms in patients with restless legs syndrome and migraine.

PubMed

Ferreira, Karen S; Eckeli, Alan; Dach, Fabíola; Speciali, José G

2013-02-01

The pathophysiology of migraine and restless legs syndrome (RLS) seems to involve inherited mechanism and dysfunction of the dopaminergic system. Previous articles have shown that the frequency of RLS is higher in migraine patients than in controls. We conducted a study to evaluate comorbidities, medication used and depressive symptoms that can explain the relation between migraine and RLS. A case-control study was performed in which patients with migraine (n=72) and a control group without migraine (n=72) were interviewed. Data including RLS diagnosis, depressive symptoms, comorbidities and drugs used were evaluated. There was a significant association between migraine and RLS (p=0.01), but comorbidities such as diabetes, hypertension, anemia and drugs used did not explain this association. Depression scores, as measured by the Beck Depression Inventory, were higher in migraine patients with RLS (p =0.04). No specific factors explaining the association between migraine and RLS were found. Symptoms of depression were more frequent in patients with migraine and RLS.

The contribution of illness perceptions and metacognitive beliefs to anxiety and depression in adults with diabetes.

PubMed

Purewal, Rebecca; Fisher, Peter L

2018-02-01

Anxiety and depression are highly prevalent in people with diabetes (PwD). The most widely used psychological model to explain anxiety and depression in PwD is the Common-Sense Model, which gives a central role to illness perceptions. The Self-Regulatory Executive Function (S-REF) model proposes metacognitive beliefs are key to understanding the development and maintenance of emotional disorders. To test the potential utility of the S-REF model in PwD, the study explored if metacognitive beliefs explained additional variance in anxiety and depression after controlling for demographic and illness perceptions. 614 adults with either Type 1 (n = 335) or Type 2 (n = 279) diabetes participated in a cross sectional online survey. All participants completed questionnaires on anxiety, depression, illness perceptions and metacognitive beliefs. Regression analyses showed that metacognitive beliefs were associated with anxiety and depression in PwD and explained additional variance in both anxiety and depression after controlling for demographics and illness perceptions. This is the first study to demonstrate that metacognitive beliefs are associated with anxiety and depression in PwD. The clinical implications of the study are illustrated. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

Anhedonia and the Relationship Between Other Depressive Symptoms and Aggressive Behavior.

PubMed

Salem, Taban; Winer, E Samuel; Jordan, D Gage; Nadorff, Michael R; Fanning, Jennifer R; Bryant, Jessica; Berman, Mitchell E; Veilleux, Jennifer C

2018-05-01

Depression has been linked to multiple forms of aggressive behavior in college students; however, it is unclear which aspects of depression explain this connection. Anhedonia, defined as the loss of interest and/or pleasure in previously enjoyed activities, may provide unique information about relationships between depression and aggression. Using cross-sectional data from two independent samples of college students ( N = 747 and N = 736 for Study 1 and Study 2, respectively), we examined whether anhedonia helped explain the relationship between broader depressive symptoms and different forms of aggressive and antisocial behavior. Anhedonia accounted for variance in both self-directed aggression and antisocial behavior independent of gender, hostility, anger, other depressive symptoms, and cognitive distortions (Study 2). In addition, there were significant indirect effects of depressive symptoms on self-directed aggression (Studies 1 and 2) and antisocial behavior (Study 2) via anhedonia. Hypotheses involving other-directed aggression received mixed support, with anhedonia atemporally associated with other-directed aggression independent of broader depressive symptoms in Study 1, but not in Study 2. The current findings suggest that anhedonia is an important individual difference that helps explain the relationship between depression and aggressive and antisocial acts and that anhedonia may be differentially associated with various types of aggressive and antisocial behavior.

New methods of testing nonlinear hypothesis using iterative NLLS estimator

NASA Astrophysics Data System (ADS)

Mahaboob, B.; Venkateswarlu, B.; Mokeshrayalu, G.; Balasiddamuni, P.

2017-11-01

This research paper discusses the method of testing nonlinear hypothesis using iterative Nonlinear Least Squares (NLLS) estimator. Takeshi Amemiya [1] explained this method. However in the present research paper, a modified Wald test statistic due to Engle, Robert [6] is proposed to test the nonlinear hypothesis using iterative NLLS estimator. An alternative method for testing nonlinear hypothesis using iterative NLLS estimator based on nonlinear hypothesis using iterative NLLS estimator based on nonlinear studentized residuals has been proposed. In this research article an innovative method of testing nonlinear hypothesis using iterative restricted NLLS estimator is derived. Pesaran and Deaton [10] explained the methods of testing nonlinear hypothesis. This paper uses asymptotic properties of nonlinear least squares estimator proposed by Jenrich [8]. The main purpose of this paper is to provide very innovative methods of testing nonlinear hypothesis using iterative NLLS estimator, iterative NLLS estimator based on nonlinear studentized residuals and iterative restricted NLLS estimator. Eakambaram et al. [12] discussed least absolute deviation estimations versus nonlinear regression model with heteroscedastic errors and also they studied the problem of heteroscedasticity with reference to nonlinear regression models with suitable illustration. William Grene [13] examined the interaction effect in nonlinear models disused by Ai and Norton [14] and suggested ways to examine the effects that do not involve statistical testing. Peter [15] provided guidelines for identifying composite hypothesis and addressing the probability of false rejection for multiple hypotheses.

An enstrophy-based linear and nonlinear receptivity theory

NASA Astrophysics Data System (ADS)

Sengupta, Aditi; Suman, V. K.; Sengupta, Tapan K.; Bhaumik, Swagata

2018-05-01

In the present research, a new theory of instability based on enstrophy is presented for incompressible flows. Explaining instability through enstrophy is counter-intuitive, as it has been usually associated with dissipation for the Navier-Stokes equation (NSE). This developed theory is valid for both linear and nonlinear stages of disturbance growth. A previously developed nonlinear theory of incompressible flow instability based on total mechanical energy described in the work of Sengupta et al. ["Vortex-induced instability of an incompressible wall-bounded shear layer," J. Fluid Mech. 493, 277-286 (2003)] is used to compare with the present enstrophy based theory. The developed equations for disturbance enstrophy and disturbance mechanical energy are derived from NSE without any simplifying assumptions, as compared to other classical linear/nonlinear theories. The theory is tested for bypass transition caused by free stream convecting vortex over a zero pressure gradient boundary layer. We explain the creation of smaller scales in the flow by a cascade of enstrophy, which creates rotationality, in general inhomogeneous flows. Linear and nonlinear versions of the theory help explain the vortex-induced instability problem under consideration.

Predicting relatedness and self-definition depressive experiences in aging women based on personality traits: a preliminary study.

PubMed

Henriques-Calado, Joana; Duarte-Silva, Maria Eugénia; Campos, Rui C; Sacoto, Carlota; Keong, Ana Marta; Junqueira, Diana

2013-01-01

As part of the research relating personality and depression, this study seeks to predict depressive experiences in aging women according to Sidney Blatt's perspective based on the Five-Factor Model of Personality. The NEO-Five Factor Inventory and the Depressive Experiences Questionnaire were administered. The domains Neuroticism, Agreeableness, and Conscientiousness predicted self-criticism, explaining 68% of the variance; the domains Neuroticism and Extraversion predicted dependency, explaining 62% of the variance. The subfactors Neediness and Connectedness were differently related to personality traits. These findings are relevant to the research relating personality and anaclitic / introjective depressive experiences in late adulthood.

Adolescence and Depression.

ERIC Educational Resources Information Center

Wisconsin Clearinghouse, Madison.

This booklet begins with a poem written by an adolescent undergoing psychotherapy for depression, then goes on to describe what depression is and to examine sex and age differences related to depression. The difference between clinical depression and feeling blue is explained. Various therapies used in the treatment of depression are identified.…

Explaining ecological clusters of maternal depression in South Western Sydney

PubMed Central

2014-01-01

Background The aim of the qualitative study reported here was to: 1) explain the observed clustering of postnatal depressive symptoms in South Western Sydney; and 2) identify group-level mechanisms that would add to our understanding of the social determinants of maternal depression. Methods Critical realism provided the methodological underpinning for the study. The setting was four local government areas in South Western Sydney, Australia. Child and Family practitioners and mothers in naturally occurring mothers groups were interviewed. Results Using an open coding approach to maximise emergence of patterns and relationships we have identified seven theoretical concepts that might explain the observed spatial clustering of maternal depression. The theoretical concepts identified were: Community-level social networks; Social Capital and Social Cohesion; "Depressed community"; Access to services at the group level; Ethnic segregation and diversity; Supportive social policy; and Big business. Conclusions We postulate that these regional structural, economic, social and cultural mechanisms partially explain the pattern of maternal depression observed in families and communities within South Western Sydney. We further observe that powerful global economic and political forces are having an impact on the local situation. The challenge for policy and practice is to support mothers and their families within this adverse regional and global-economic context. PMID:24460690

Nonlinear behaviour of reflectivity of gallium - Silica interface & its applications

NASA Astrophysics Data System (ADS)

Naruka, Preeti; Bissa, Shivangi

2018-05-01

In this paper Optical properties and nonlinear behaviour of Gallium-Silica Interface is studied. Change in reflectivity of gallium film is explained as a function of thickness of metallic layer and intensity of incident light by using non-thermal mechanism. Here variation of dielectric constant of gallium with temperature is also explained on considering Binary nanoshell model of gallium nanoparticles of spherical shape. In the present paper application of structural phase transformation of gallium is explained as a Grating assisted coupler.

Power laws in covariability of anxiety and depression among newly diagnosed patients with major depressive episode, panic disorder and controls.

PubMed

Katerndahl, David A

2009-06-01

Although symptoms of anxiety and depression correlate, they may covary in irregular and unpredictable ways. This non-linear covariation may be important to psychiatric diagnosis, treatment and relapse. This non-linear anxiety-depression interaction suggests that power laws may be observed. Power laws are statistical distributions found when systems vary in complex ways at the interface between chaotic dynamics and periodic dynamics, such that data points vary randomly but are still partially correlated with each other. Such non-linear dynamics and relationships should result in characteristic patterns of interaction among patients, stressors and treatment. This is important because non-linear dynamics could affect our understanding of mental disorders, the need for varied treatment approaches and patterns of early response to treatment. To determine whether the relationships between anxiety and depression levels, changes and rates of change follow power law distributions among patients with newly diagnosed major depressive episode (MDE), panic disorder (PD) and neither disorder (controls). Time series of hourly mood variation. Setting Acute and continuity primary care clinics. Five adult patients presenting each with MDE, PD and controls based on DSM-IV criteria. Four patients in each group completed 30 days of assessments. MAIN AND SECONDARY OUTCOME MEASURES: Hourly self-assessments (while awake) of levels of anxiety and depression using visual analogue scales for a 30-day period. Covariation in level of symptoms, in the change of symptoms and in the rate of change were assessed. Anxiety-depression matrices were prepared for pooled subjects. Power laws were sought using log-log plots of frequency versus order of that frequency. Although visual inspection of plots for symptoms levels, change and rates of change all suggest power laws, statistical assessments provide stronger support for power laws in symptom change than for either symptom levels or rates of change. Adjusted R(2) terms are larger for MDE and PD subjects compared with controls while the inverse slope is about 2.5 for controls and 1.7-1.9 for those with MDE or PD. This study found that power laws may be present in both the symptom change data for all three diagnostic groups. Evidence for power laws in symptom levels and rates of change was less compelling. The inverse slopes suggest that the anxiety-depression relationships among subjects with PD and major depression are similar but differ from those among controls. First, power laws suggest a scale-free relationship; the differences seen in transition from symptom level to change level may reflect that complex events at the level of mood assessment affect change in mood. Second, this covariation may be due to external factors acting on the patient or multiple internal interrelated factors. Third, different factors and populations can yield different slopes. Future research is needed to confirm these preliminary findings and to understand the origin of these dynamics.

Derivation of an applied nonlinear Schroedinger equation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pitts, Todd Alan; Laine, Mark Richard; Schwarz, Jens

We derive from first principles a mathematical physics model useful for understanding nonlinear optical propagation (including filamentation). All assumptions necessary for the development are clearly explained. We include the Kerr effect, Raman scattering, and ionization (as well as linear and nonlinear shock, diffraction and dispersion). We explain the phenomenological sub-models and each assumption required to arrive at a complete and consistent theoretical description. The development includes the relationship between shock and ionization and demonstrates why inclusion of Drude model impedance effects alters the nature of the shock operator. Unclassified Unlimited Release

Do secondary conditions explain the relationship between depression and health care cost in women with physical disabilities?

PubMed

Morgan, Robert O; Byrne, Margaret M; Hughes, Rosemary B; Petersen, Nancy J; Taylor, Heather B; Robinson-Whelen, Susan; Hasche, Jennifer C; Nosek, Margaret A

2008-10-01

To examine the influence of depression on health care utilization and costs among women with disabilities and to determine whether the severity of other secondary health conditions affects this association. A time series of 7 interviews over a 1-year period. Large, southern metropolitan area. Community-dwelling women (N=349) with a self-identified diagnosis of a physical disability. Not applicable. Primary disability, secondary health conditions (Health Conditions Checklist), depressive symptoms (Beck Depression Inventory-Second Edition), and health care utilization (based on the Health and Social Service Utilization Questionnaire and the Stanford Health Assessment Questionnaire). We estimated health care costs using standardized criteria and published average costs. Outpatient and emergency department health care utilization and overall costs were higher in women with depressive symptoms and increased with the frequency and severity of the symptoms. Depressive symptoms were highly correlated with the severity of secondary health conditions. Adjusting for demographics and primary disability, both the presence and severity of depressive symptoms were associated with significantly higher health care costs. However, secondary health condition severity explained the association between depressive symptoms and cost; it also substantially increased the variance in cost that was explained by the multivariate models. Secondary health conditions are significantly associated with depressive symptoms and higher health care costs, with secondary health conditions accounting for the association between depressive symptoms and costs. This association suggests that effective management of secondary health conditions may help reduce both depressive symptomatology and health care costs.

Acculturation, Gender, Depression, and Cigarette Smoking Among U.S. Hispanic Youth: The Mediating Role of Perceived Discrimination

PubMed Central

Unger, Jennifer B.; Ritt-Olson, Anamara; Soto, Daniel; Baezconde-Garbanati, Lourdes

2013-01-01

Hispanic youth are at risk for experiencing depressive symptoms and smoking cigarettes, and risk for depressive symptoms and cigarette use increase as Hispanic youth acculturate to U.S. culture. The mechanism by which acculturation leads to symptoms of depression and cigarette smoking is not well understood. The present study examined whether perceived discrimination explained the associations of acculturation with depressive symptoms and cigarette smoking among 1,124 Hispanic youth (54% female). Youth in Southern California completed surveys in 9th–11th grade. Separate analyses by gender showed that perceived discrimination explained the relationship between acculturation and depressive symptoms for girls only. There was also evidence that discrimination explained the relationship between acculturation and cigarette smoking among girls, but the effect was only marginally significant. Acculturation was associated with depressive symptoms and smoking among girls only. Perceived discrimination predicted depressive symptoms in both genders, and discrimination was positively associated with cigarette smoking for girls but not boys. These results support the notion that, although Hispanic boys and girls experience acculturation and discrimination, their mental health and smoking behaviors are differentially affected by these experiences. Moreover, the results indicate that acculturation, gender, and discrimination are important factors to consider when addressing Hispanic youth’s mental health and substance use behaviors. PMID:21293915

Acculturation, gender, depression, and cigarette smoking among U.S. Hispanic youth: the mediating role of perceived discrimination.

PubMed

Lorenzo-Blanco, Elma I; Unger, Jennifer B; Ritt-Olson, Anamara; Soto, Daniel; Baezconde-Garbanati, Lourdes

2011-11-01

Hispanic youth are at risk for experiencing depressive symptoms and smoking cigarettes, and risk for depressive symptoms and cigarette use increase as Hispanic youth acculturate to U.S. culture. The mechanism by which acculturation leads to symptoms of depression and cigarette smoking is not well understood. The present study examined whether perceived discrimination explained the associations of acculturation with depressive symptoms and cigarette smoking among 1,124 Hispanic youth (54% female). Youth in Southern California completed surveys in 9th-11th grade. Separate analyses by gender showed that perceived discrimination explained the relationship between acculturation and depressive symptoms for girls only. There was also evidence that discrimination explained the relationship between acculturation and cigarette smoking among girls, but the effect was only marginally significant. Acculturation was associated with depressive symptoms and smoking among girls only. Perceived discrimination predicted depressive symptoms in both genders, and discrimination was positively associated with cigarette smoking for girls but not boys. These results support the notion that, although Hispanic boys and girls experience acculturation and discrimination, their mental health and smoking behaviors are differentially affected by these experiences. Moreover, the results indicate that acculturation, gender, and discrimination are important factors to consider when addressing Hispanic youth's mental health and substance use behaviors.

Reinforcement expectations explain the relationship between depressive history and smoking status in college students.

PubMed

McChargue, Dennis E; Spring, Bonnie; Cook, Jessica W; Neumann, Christopher A

2004-07-01

Little is understood about biobehavioral mechanisms that mediate the comorbidity between cigarette smoking and depression. We hypothesized that expectancies about nicotine's reinforcing effects are associated with vulnerability to depression, and may partially explain the relationship between history of depression and smoking. Young adult smokers and never smokers (N=175, mean age=19.9 years, S.D.=3.2) were assessed for history of depression and expectations about the negative (e.g., dispels bad moods) and positive (e.g., increases pleasure) reinforcing effects of smoking. Results are inconsistent with the premise that negative reinforcement expectancies mediate the comorbidity between depression and nicotine dependence. Instead, findings suggest that young adults with a prior history of major depression hold exaggerated expectations about nicotine's positive effects, which could enhance their likelihood of initiating smoking. Copyright 2004 Elsevier Ltd.

Nonlinear digital signal processing in mental health: characterization of major depression using instantaneous entropy measures of heartbeat dynamics.

PubMed

Valenza, Gaetano; Garcia, Ronald G; Citi, Luca; Scilingo, Enzo P; Tomaz, Carlos A; Barbieri, Riccardo

2015-01-01

Nonlinear digital signal processing methods that address system complexity have provided useful computational tools for helping in the diagnosis and treatment of a wide range of pathologies. More specifically, nonlinear measures have been successful in characterizing patients with mental disorders such as Major Depression (MD). In this study, we propose the use of instantaneous measures of entropy, namely the inhomogeneous point-process approximate entropy (ipApEn) and the inhomogeneous point-process sample entropy (ipSampEn), to describe a novel characterization of MD patients undergoing affective elicitation. Because these measures are built within a nonlinear point-process model, they allow for the assessment of complexity in cardiovascular dynamics at each moment in time. Heartbeat dynamics were characterized from 48 healthy controls and 48 patients with MD while emotionally elicited through either neutral or arousing audiovisual stimuli. Experimental results coming from the arousing tasks show that ipApEn measures are able to instantaneously track heartbeat complexity as well as discern between healthy subjects and MD patients. Conversely, standard heart rate variability (HRV) analysis performed in both time and frequency domains did not show any statistical significance. We conclude that measures of entropy based on nonlinear point-process models might contribute to devising useful computational tools for care in mental health.

Perceived Weight Discrimination Mediates the Prospective Relation Between Obesity and Depressive Symptoms in U.S. and U.K. Adults

PubMed Central

2016-01-01

Objective: Obesity has been shown to increase risk of depression. Persons with obesity experience discrimination because of their body weight. Across 3 studies, we tested for the first time whether experiencing (perceived) weight-based discrimination explains why obesity is prospectively associated with increases in depressive symptoms. Method: Data from 3 studies, including the English Longitudinal Study of Ageing (2008/2009–2012/2013), the Health and Retirement Study (2006/2008–2010/2012), and Midlife in the United States (1995/1996–2004/2005), were used to examine associations between obesity, perceived weight discrimination, and depressive symptoms among 20,286 U.S. and U.K. adults. Results: Across all 3 studies, Class II and III obesity were reliably associated with increases in depressive symptoms from baseline to follow-up. Perceived weight-based discrimination predicted increases in depressive symptoms over time and mediated the prospective association between obesity and depressive symptoms in all 3 studies. Persons with Class II and III obesity were more likely to report experiencing weight-based discrimination, and this explained approximately 31% of the obesity-related increase in depressive symptoms on average across the 3 studies. Conclusion: In U.S. and U.K. samples, the prospective association between obesity (defined using body mass index) and increases in depressive symptoms in adulthood may in part be explained by perceived weight discrimination. PMID:27748611

Down or up? Explaining positive and negative emotions in parents of children with Down's syndrome: Goals, cognitive coping, and resources.

PubMed

Van Der Veek, Shelley M C; Kraaij, Vivian; Garnefski, Nadia

2009-09-01

Some studies find that parents of children with Down's syndrome may experience symptoms of depression, while other studies find that parents adapt well. This study aimed to clarify this variability in adaptive strength by investigating a stress-coping model to explain depressive symptoms and positive affect. Questionnaires were completed by 553 parents of children (aged 0-18) with Down's syndrome, containing measures of goal disturbance, cognitive coping, social support, partner bonding, and coping self-efficacy. Different models for positive affect and depressive symptoms were found. The coping strategies of self-blame and rumination were positively related to depressive symptoms, and positive reappraisal was positively related to positive affect. Partner bonding characteristics played relevant roles in both models, as did coping self-efficacy and goal disturbance. Social support seemed mainly relevant in explaining positive affect. Different psychological factors were related to depressive symptoms and positive affect in parents of children with Down's syndrome. Implications are discussed.

Do sex differences in rumination explain sex differences in depression?

PubMed

Shors, Tracey J; Millon, Emma M; Chang, Han Yan M; Olson, Ryan L; Alderman, Brandon L

2017-01-02

It is generally accepted that women tend to ruminate more than men do and these thought patterns are often associated with depressive symptoms (Nolen-Hoeksema et al., ). Based on these findings, we considered whether the relationship between rumination and depression is stronger in women than in men and if so, whether this might explain the higher prevalence of major depressive disorder (MDD) in women and finally, whether the association can be disrupted through a mind/body intervention. Adult men and women, most of whom were clinically depressed, participated in an intervention known as MAP Training, which combines "mental" training with silent meditation and "physical" training with aerobic exercise (Shors et al., ). After eight weeks of training, both men and women reported significantly fewer symptoms of depression and fewer ruminative thoughts (Alderman et al., ). Statistical correlations between depressive symptoms and ruminative thoughts were strong and significant (rho > 0.50; p < 0.05) for both men and women before and after MAP Training. However, only in women did depressive symptoms relate to "reflective" ruminations, which involve analyses of past events, feelings, and behaviors. This is also the only relationship that dissipated after the intervention. In general, these analyses suggest that the strength of the relationship between depressive symptoms and rumination does not necessarily explain sex differences in depression; but because the relationship is strong, targeting rumination through intervention can reduce the incidence of MDD, which is more prevalent among women. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Hopelessness, Depression, Suicidal Ideation, and Clinical Diagnosis of Depression.

ERIC Educational Resources Information Center

Beck, Aaron T.; And Others

1993-01-01

Examined relevance of clinical diagnosis of depression for explaining discrepant relationships of hopelessness and depression with suicidal ideation. Administered Beck Depression Inventory, Hopelessness Scale, and Scale for Suicide Ideation to 1,306 patients with mood disorder and 488 patients without mood disorder. Found that hopelessness was 1.3…

Negative cognitive style and cortisol recovery accentuate the relationship between life stress and depressive symptoms.

PubMed

Quinn, Meghan E; Grant, Kathryn E; Adam, Emma K

2018-03-01

When exposed to stressful life events, a significant number of adolescents will experience depressive symptoms. One model of depression suggests that individuals with a negative cognitive style are most vulnerable to depression following life stress. Alternatively, altered activation of the hypothalamic-pituitary-adrenal axis may explain vulnerability to depression following life stress. Each of these models plausibly explains the emergence of depressive symptoms during adolescence and have been investigated largely independently. The current study recruited a sample of urban adolescents (N = 179) to evaluate whether cortisol response to a laboratory stress induction and negative cognitive style are related and whether they independently interact with exposure to stressful life events to predict symptoms of depression. Negative cognitive style was not associated with cortisol response to the laboratory stressor. Rather, negative cognitive style and cortisol recovery independently interacted with stressful life events to predict current symptoms of depression. Results support a heterogeneous etiology of depression.

Thought Control Ability Is Different from Rumination in Explaining the Association between Neuroticism and Depression: A Three-Study Replication

PubMed Central

Lu, Feng-Ying; Yang, Wen-Jing; Zhang, Qing-Lin; Qiu, Jiang

2017-01-01

Neuroticism is the most common vulnerability factor of depression. However, the mechanism underlying this vulnerability is still unclear. Previous studies suggested that rumination intensifies the negative effect of neuroticism on depression. However, whether cognitive control could explain the association between neuroticism and depression remains unclear to date. Therefore, this study evaluated the indirect effects of rumination and thought control on the relationship between neuroticism and depression. Seven self-report measures were employed among healthy and main depression disorder (MDD) participants. Three studies were used to examine the hypotheses. Results of the three studies showed significant correlations among neuroticism, rumination, thought control, and depression. Rumination mediated the link between neuroticism and depression among healthy young adults, and this finding replicated previous studies. This study provided new evidence that thought control mediates the association between neuroticism and depression in both healthy and MDD populations. In conclusion, rumination increases neuroticism risk for depression, but high-level thought control decreases the effect of neuroticism on depression. This study may serve as a reference to develop effective and focused interventions for MDD patients. PMID:28620326

Electroconvulsive Therapy: A Primer for Mental Health Counselors.

ERIC Educational Resources Information Center

Leinbaugh, Tracy C.

2001-01-01

Electroconvulsive therapy is the treatment of choice for severe depressive episodes. Although little definitive research exists to explain its effectiveness, since its development in 1938 it has proven effective for the treatment of depression with psychotic features and suicidal ideation. Explains the procedure and discusses implications for the…

The dynamics of physical and mental health in the older population.

PubMed

Ohrnberger, Julius; Fichera, Eleonora; Sutton, Matt

2017-06-01

Mental and physical aspects are both integral to health but little is known about the dynamic relationship between them. We consider the dynamic relationship between mental and physical health using a sample of 11,203 individuals in six waves (2002-2013) of the English Longitudinal Study of Ageing (ELSA). We estimate conditional linear and non-linear random-effects regression models to identify the effects of past physical health, measured by Activities of Daily Living (ADL), and past mental health, measured by the Centre for Epidemiological Studies Depression (CES-D) scale, on both present physical and mental health. We find that both mental and physical health are moderately state-dependent. Better past mental health increases present physical health significantly. Better past physical health has a larger effect on present mental health. Past mental health has stronger effects on present physical health than physical activity or education. It explains 2.0% of the unobserved heterogeneity in physical health. Past physical health has stronger effects on present mental health than health investments, income or education. It explains 0.4% of the unobserved heterogeneity in mental health. These cross-effects suggest that health policies aimed at specific aspects of health should consider potential spill-over effects.

Time series with tailored nonlinearities

NASA Astrophysics Data System (ADS)

Räth, C.; Laut, I.

2015-10-01

It is demonstrated how to generate time series with tailored nonlinearities by inducing well-defined constraints on the Fourier phases. Correlations between the phase information of adjacent phases and (static and dynamic) measures of nonlinearities are established and their origin is explained. By applying a set of simple constraints on the phases of an originally linear and uncorrelated Gaussian time series, the observed scaling behavior of the intensity distribution of empirical time series can be reproduced. The power law character of the intensity distributions being typical for, e.g., turbulence and financial data can thus be explained in terms of phase correlations.

Explaining the sex difference in depression with a unified bargaining model of anger and depression

PubMed Central

Hagen, Edward H.; Rosenström, Tom

2016-01-01

Background: Women are twice as likely as men to be depressed, a bias that is poorly understood. One evolutionary model proposes that depression is a bargaining strategy to compel reluctant social partners to provide more help in the wake of adversity. An evolutionary model of anger proposes that high upper body strength predisposes individuals to angrily threaten social partners who offer too few benefits or impose too many costs. Here, we propose that when social partners provide too few benefits or impose too many costs, the physically strong become overtly angry and the physically weak become depressed. The sexual dimorphism in upper body strength means that men will be more likely to bargain with anger and physical threats and women with depression. Methodology: We tested this idea using the 2011–12 National Health and Nutrition Examination Survey (NHANES), a large nationally representative sample of US households that included measures of depression and upper body strength. Results: A 2 SD increase in grip strength decreased the odds of depression by more than half (OR=0.4, P=0.0079), which did not appear to be a consequence of confounds with anthropometric, hormonal or socioeconomic variables, but was partially explained by a confound with physical disability. Nevertheless, upper body strength mediated 63% of the effect of sex on depression, but the mediation effect was unexpectedly moderated by age. Conclusions: Low upper body strength is a risk factor for depression, especially in older adults, and the sex difference in body strength appears to explain much of the perplexing sex difference in depression. PMID:26884416

Microcomputer Simulation of Nonlinear Systems: From Oscillations to Chaos.

ERIC Educational Resources Information Center

Raw, Cecil J. G.; Stacey, Larry M.

1989-01-01

Presents two short microcomputer programs which illustrate features of nonlinear dynamics, including steady states, periodic oscillations, period doubling, and chaos. Logistic maps are explained, inclusion in undergraduate chemistry and physics courses to teach nonlinear equations is discussed, and applications in social and biological sciences…

Can home-monitoring of sleep predict depressive episodes in bipolar patients?

PubMed

Migliorini, M; Mariani, S; Bertschy, G; Kosel, M; Bianchi, A M

2015-08-01

The aim of this study is the evaluation of the autonomic regulations during depressive stages in bipolar patients in order to test new quantitative and objective measures to detect such events. A sensorized T-shirt was used to record ECG signal and body movements during the night, from which HRV data and sleep macrostructure were estimated and analyzed. 9 out of 20 features extracted resulted to be significant (p<;0.05) in discriminating among depressive and non-depressive states. Such features are representation of HRV dynamics in both linear and non-linear domain and parameters linked to sleep modulations.

It Takes Three: Selection, Influence, and De-Selection Processes of Depression in Adolescent Friendship Networks

ERIC Educational Resources Information Center

Van Zalk, Maarten Herman Walter; Kerr, Margaret; Branje, Susan J. T.; Stattin, Hakan; Meeus, Wim H. J.

2010-01-01

The authors of this study tested a selection-influence-de-selection model of depression. This model explains friendship influence processes (i.e., friends' depressive symptoms increase adolescents' depressive symptoms) while controlling for two processes: friendship selection (i.e., selection of friends with similar levels of depressive symptoms)…

Self-control and its relation to joint developmental trajectories of cannabis use and depressive mood symptoms.

PubMed

Otten, Roy; Barker, Edward D; Maughan, Barbara; Arseneault, Louise; Engels, Rutger C M E

2010-12-01

Cannabis use and depressive mood symptoms in adolescence have been found to co-occur. In exploring the nature of this relationship and in the search for mechanisms that explain this link, scholars have postulated the idea for a 'common liability model'. According to this model, the link between cannabis use and depressive symptoms can be explained by an underlying risk factor. One important candidate for this underlying risk factor may be self-control, as a reflection of immature self-regulatory systems in adolescence. In the present study, we will test the extent to which joint development of cannabis use and depressive symptoms can be explained as an expression of self-control. A total of 428 adolescents participated in a five-wave longitudinal design. Main study outcomes were self-reports of self-control (age 12) and cannabis use and depressive symptoms (ages 12-16). We established six trajectories of joint development of cannabis use and depressive symptoms. Conditional probabilities indicated that cannabis use and depressive symptoms were symmetrically related. Levels of self-control were lowest for adolescents following the joint developmental pathway of cannabis use and high depressive symptoms. Low levels of self-control are predictive of joint development of cannabis use and depressive symptoms. Future studies should concentrate on the role of self-control in co-occurrence of other health risk behaviors and on psychological and physiological mechanisms underlying self-control and its relation to co-occurrence. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Parenting and Adolescents' Depressive Symptoms: The Mediating Role of Future Time Perspective.

PubMed

Diaconu-Gherasim, Loredana R; Bucci, Colleen M; Giuseppone, Kathryn R; Brumariu, Laura E

2017-10-03

This study investigated the relations between maternal and paternal rearing practices and adolescents' depressive symptoms, and whether time perspective in adolescence explains these links. The sample included 306 students (158 girls), aged between 10.83 and 14.42 years. Adolescents completed questionnaires assessing their perceptions of maternal and paternal acceptance and psychological control, and of their future time perspective and depressive symptoms. Adolescents who rated their mothers as more accepting and those who rated their fathers as less psychologically controlling also reported lower levels of depressive symptoms and greater future time perspective. Further, adolescents who had greater future time perspective reported lower levels of depressive symptoms. Finally, time perspective partially mediated the relations of maternal and paternal acceptance, and paternal control with depressive symptoms in adolescence. The findings highlight the unique relations of maternal acceptance and paternal psychological control with adolescents' depressive symptoms, and that future time perspective is one mechanism that might explain why parenting strategies are linked with depressive symptoms in adolescence.

The Effects of Gender Differences in Patients with Depression on Their Emotional Working Memory and Emotional Experience

PubMed Central

Li, Mi; Lu, Shengfu; Wang, Gang; Zhong, Ning

2015-01-01

A large amount of research has been conducted on the effects of sex hormones on gender differences in patients with depression, yet research on cognitive differences between male and female patients with depression is insufficient. This study uses emotion pictures to investigate the differences of the emotional working memory ability and emotional experience in male and female patients with depression. Despite identifying that the working memory of patients with depression is impaired, our study found no significant gender differences in emotional working memory. Moreover, the research results revealed that memory effects of mood congruence are produced in both men and women, which may explain why the depression state can be maintained. Furthermore, female patients have more emotional experiences than male patients, which is particularly significant in terms of negative emotional experiences. This result provides cognitive evidence to explain why women suffer from longer terms of depression, are more susceptible to relapse, and can more easily suffer from major depressive disorder in the future. PMID:26578820

Preadolescent Clues to Understanding Depression in Girls

PubMed Central

Keenan, Kate; Hipwell, Alison E.

2010-01-01

Between the ages of 10 and 15, increases in depression among girls result in a rate that is twice as high as the rate of depression in boys. This sex difference remains throughout early and middle adulthood. Prior to early adolescence, there is essentially no sex difference in the rate of depression. The aim of the present review is to examine whether the preadolescent period is a time during which precursors to depression in girls can be identified. First, existing areas of research on explaining sex differences in depression, including cognitive and affiliative style and the socialization of emotion, are reviewed. Second, the hypothesis that for some girls, preadolescent precursors to depression take the form of excessive empathy, compliance and regulation of negative emotions is articulated. Third, ways of building on existing models by including the proposed preadolescent precursors are proposed. Finally, approaches to testing the hypotheses that individual differences in these domains during preadolescence may explain later individual differences in adolescent onset depression are explored. PMID:15984082

Nonlinear modulation of interacting between COMT and depression on brain function.

PubMed

Gong, L; He, C; Yin, Y; Ye, Q; Bai, F; Yuan, Y; Zhang, H; Lv, L; Zhang, H; Zhang, Z; Xie, C

2017-09-01

The catechol-O-methyltransferase (COMT) gene is related to dopamine degradation and has been suggested to be involved in the pathogenesis of major depressive disorder (MDD). However, how this gene affects brain function properties in MDD is still unclear. Fifty patients with MDD and 35 cognitively normal participants underwent a resting-state functional magnetic resonance imaging scan. A voxelwise and data-drive global functional connectivity density (gFCD) analysis was used to investigate the main effects and the interactions of disease states and COMT rs4680 gene polymorphism on brain function. We found significant group differences of the gFCD in bilateral fusiform area (FFA), post-central and pre-central cortex, left superior temporal gyrus (STG), rectal and superior temporal gyrus and right ventrolateral prefrontal cortex (vlPFC); abnormal gFCDs in left STG were positively correlated with severity of depression in MDD group. Significant disease×COMT interaction effects were found in the bilateral calcarine gyrus, right vlPFC, hippocampus and thalamus, and left SFG and FFA. Further post-hoc tests showed a nonlinear modulation effect of COMT on gFCD in the development of MDD. Interestingly, an inverted U-shaped modulation was found in the prefrontal cortex (control system) but U-shaped modulations were found in the hippocampus, thalamus and occipital cortex (processing system). Our study demonstrated nonlinear modulation of the interaction between COMT and depression on brain function. These findings expand our understanding of the COMT effect underlying the pathophysiology of MDD. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Development of computer program NAS3D using Vector processing for geometric nonlinear analysis of structures

NASA Technical Reports Server (NTRS)

Mangalgiri, P. D.; Prabhakaran, R.

1986-01-01

An algorithm for vectorized computation of stiffness matrices of an 8 noded isoparametric hexahedron element for geometric nonlinear analysis was developed. This was used in conjunction with the earlier 2-D program GAMNAS to develop the new program NAS3D for geometric nonlinear analysis. A conventional, modified Newton-Raphson process is used for the nonlinear analysis. New schemes for the computation of stiffness and strain energy release rates is presented. The organization the program is explained and some results on four sample problems are given. The study of CPU times showed that savings by a factor of 11 to 13 were achieved when vectorized computation was used for the stiffness instead of the conventional scalar one. Finally, the scheme of inputting data is explained.

Progression of motor and nonmotor features of Parkinson's disease and their response to treatment

PubMed Central

Vu, Thuy C.; Nutt, John G.; Holford, Nicholas H. G.

2012-01-01

AIMS (i) To describe the progression of the cardinal features of Parkinson's disease (PD); (ii) to investigate whether baseline PD subtypes explain disease progression; and (iii) to quantify the symptomatic and disease-modifying effects of anti-parkinsonian treatments. METHODS Data were available for 795 PD subjects, initially untreated, followed for up to 8 years. Cardinal features [tremor, rigidity, bradykinesia, and postural instability and gait disorder (PIGD)] were derived from the total unified Parkinson's disease rating scale (total UPDRS), cognitive status from the mini-mental status exam score (MMSE) and depression status from the Hamilton depression scale (HAM-D). Analysis was performed using a nonlinear mixed effects approach with an asymptotic model for natural disease progression. Treatment effects (i.e. symptomatic and disease modifying) were evaluated by describing changes in the natural history model parameters. RESULTS Tremor progressed more slowly (half-time of 3.9 years) than all other motor features (half-time 2–3 years). The MMSE progression was negligible, while HAM-D progressed with a half-time of 5 years. Levodopa had marked symptomatic effects on all features, but low potency for effect on PIGD (ED50 of 1237 mg day−1 compared with 7–24 mg day−1 for other motor and nonmotor features). Other anti-parkinsonian treatments had much smaller symptomatic effects. All treatments had disease-modifying effects on the cardinal features of PD. Baseline PD subtypes only explained small differences in disease progression. CONCLUSIONS This analysis indicates that tremor progresses more slowly than other cardinal features and that PIGD is less treatment responsive in early PD patients. There was no evidence of baseline PD subtypes as a clinically useful predictor of disease progression rate. Anti-parkinsonian treatments have symptomatic and disease-modifying effects on all major features of PD. PMID:22283961

Dose–response association of screen time-based sedentary behaviour in children and adolescents and depression: a meta-analysis of observational studies

PubMed Central

Liu, Mingli; Wu, Lang; Yao, Shuqiao

2016-01-01

Background Depression represents a growing public health burden. Understanding how screen time (ST) in juveniles may be associated with risk of depression is critical for the development of prevention and intervention strategies. Findings from studies addressing this question thus far have been inconsistent. Therefore, we conducted a comprehensive systematic review and meta-analysis of data related to this question. Methods The meta-analysis was conducted in accordance with the PRISMA guideline. We searched the electronic databases of PubMed, Web of Science and EBSCO systematically (up to 6 May 2015). OR was adopted as the pooled measurement of association between ST and depression risk. Dose–response was estimated by a generalised least squares trend estimation. Results Twelve cross-sectional studies and four longitudinal studies (including 1 cohort study) involving a total of 127 714 participants were included. Overall, higher ST in preadolescent children and adolescents was significantly associated with a higher risk of depression (OR=1.12; 95% CI 1.03 to 1.22). Screen type, age, population and reference category acted as significant moderators. Compared with the reference group who had no ST, there was a non-linear dose–response association of ST with a decreasing risk of depression at ST<2 h/day, with the lowest risk being observed for 1 h/day (OR=0.88; 95% CI 0.84 to 0.93). Conclusions Our meta-analysis suggests that ST in children and adolescents is associated with depression risk in a non-linear dose–response manner. PMID:26552416

Ageing, social class and common mental disorders: longitudinal evidence from three cohorts in the West of Scotland.

PubMed

Green, M J; Benzeval, M

2011-03-01

Understanding how common mental disorders such as anxiety and depression vary with socio-economic circumstances as people age can help to identify key intervention points. However, much research treats these conditions as a single disorder when they differ significantly in terms of their disease burden. This paper examines the socio-economic pattern of anxiety and depression separately and longitudinally to develop a better understanding of their disease burden for key social groups at different ages. The Twenty-07 Study has followed 4510 respondents from three cohorts in the West of Scotland for 20 years and 3846 respondents had valid data for these analyses. Hierarchical repeated-measures models were used to investigate the relationship between age, social class and the prevalence of anxiety and depression over time measured as scores of 8 or more out of 21 on the relevant subscale of the Hospital Anxiety and Depression Scale (HADS). Social class differences in anxiety and depression widened with age. For anxiety there was a nonlinear decrease in prevalence with age, decreasing more slowly for those from manual classes compared to non-manual, whereas for depression there was a non-linear increase in prevalence with age, increasing more quickly for those from manual classes compared to non-manual. This relationship is robust to cohort, period and attrition effects. The more burdensome disorder of depression occurs more frequently at ages where socio-economic inequalities in mental health are greatest, representing a 'double jeopardy' for older people from a manual class.

Explaining the sex difference in depression with a unified bargaining model of anger and depression.

PubMed

Hagen, Edward H; Rosenström, Tom

2016-01-01

Women are twice as likely as men to be depressed, a bias that is poorly understood. One evolutionary model proposes that depression is a bargaining strategy to compel reluctant social partners to provide more help in the wake of adversity. An evolutionary model of anger proposes that high upper body strength predisposes individuals to angrily threaten social partners who offer too few benefits or impose too many costs. Here, we propose that when social partners provide too few benefits or impose too many costs, the physically strong become overtly angry and the physically weak become depressed. The sexual dimorphism in upper body strength means that men will be more likely to bargain with anger and physical threats and women with depression. We tested this idea using the 2011-12 National Health and Nutrition Examination Survey (NHANES), a large nationally representative sample of US households that included measures of depression and upper body strength. A 2 SD increase in grip strength decreased the odds of depression by more than half ([Formula: see text],[Formula: see text]), which did not appear to be a consequence of confounds with anthropometric, hormonal or socioeconomic variables, but was partially explained by a confound with physical disability. Nevertheless, upper body strength mediated 63% of the effect of sex on depression, but the mediation effect was unexpectedly moderated by age. Low upper body strength is a risk factor for depression, especially in older adults, and the sex difference in body strength appears to explain much of the perplexing sex difference in depression. © The Author(s) 2016. Published by Oxford University Press on behalf of the Foundation for Evolution, Medicine, and Public Health.

A study of depression among Alexandria preparatory school adolescents.

PubMed

Abou Nazel, M W; Fahmy, S I; Younis, I A; Seif el-Din, A G; Abdel Fatah, M; Mokhtar, S; Ayoub, A I

1991-01-01

Using a constructed Arabic version of Children Depression Inventory (CDI), screening of a stratified random sample of 1% (1561) of Alexandria Preparatory school adolescents was carried out. The prevalence of depressive scorers was 10.25% of total sample. A sub-sample of depressed scorers (111 pupils) were compared with controls (non-depressed scorers) matched on age and sex to study a variety of personal, familial, medical and scholastic ecological variables. Pupils neuroticism scorers were most predictive of depressive scorers where they explained 59.79% of the variance. Other ecological factors including peer and sibling relationships, introversive and lie scale scorers and scholastic performance explained an additional 14.87% of the variance. Using Beck Depression Inventory (BDI) and Mother-Father relationship check list, a sub-sample of depressed pupils' mothers were compared with controls of non-depressed pupils' mothers (42 mothers for each). Results indicated a strong positive correlation between pupils, CDI scores and their mothers BDI scores. On the other hand poor mother-father relationship was significantly associated with depressive scores of pupils. Findings, pointed to the need for reconsideration of school mental health program, since the presented medical and social services to depressed pupils were very poor.

Using Exercise to Ward Off Depression.

ERIC Educational Resources Information Center

Nicoloff, George; Schwenk, Thomas L.

1995-01-01

Exercise can be as effective as psychotherapy and antidepressant therapy in treating mild-to-moderate depression, and even more effective when used in conjunction with them. Exercise can also be preventive therapy for those not clinically depressed. The paper explains how best to work exercise into a depressed patient's therapy. (Author/SM)

Different pathways explain alcohol related problems in female and male college students

PubMed Central

Pedrelli, P.; Collado, A.; Shapero, B. G.; Brill, C.; MacPherson, L.

2016-01-01

Objectives Comprehensive models elucidating the intricate associations of depressive symptoms, coping motives, alcohol use, alcohol-related problems (ARP) and gender among young adults have been scarcely examined. This study investigated relationships among these variables and the effect of gender on these pathways. Methods College students (N = 163; 49.7% female) completed self-report measures on alcohol consumption, depressive symptoms, coping motives, and ARPs. Results Structural equation modeling showed that the association between depressive symptoms and ARPs was mediated by coping motives in both females and males. However, frequency of heavy alcohol use mediated the association between depressive symptoms and ARPs in females but not in males. Conclusions Different models explain the association between depressive symptoms and ARPs in male and female college students. Prevention programs aimed at reducing ARPs should focus on increasing alcohol screening among students with depressive symptoms, teaching coping skills, and emphasizing moderation in alcohol consumption. PMID:27219280

Mental state and its psychophysical conditions in patients with acute leukaemia treated with bone marrow transplantation.

PubMed

Warchala, Anna; Wojtyna, Ewa; Krysta, Krzysztof

2015-09-01

Acute leukaemia and bone marrow transplantation (BMT) as a method of its treatment are great psychological stressors, which are responsible for anxiety and depression in the group of patients. The aim of the study was to assess the patients' mental state and its psychophysical predictors before and after BMT. The study was of a longitudinal and self-descriptive character. The questionnaires: LOT-R, AIS, Mini-Mac, CECS, RSCL and HADS were filled by 60 patients with acute leukaemia before and after BMT. There were no essential statistical differences between the severity of anxiety and depression before and after BMT but the pattern and the power of various mental state predictors changed in the course of the hospitalization. Anxiety before transplantation was greater when the psychological stress and the strategy of "anxious preoccupation" were stronger and the strategy of "fighting spirit" and the level of generalized optimism were weaker. The factors explained 51% variations of anxiety before transplantation. After BMT 77% variations of anxiety were explained, which were associated with a high level of distress at the end of the hospitalization, higher level of anxiety before transplantation, weaker strategy of "fighting spirit" before transplantation and stronger strategy of "anxious preoccupation" after BMT. Before transplantation 36% variations of depression were explained and estimated as weaker "fighting spirit" and worse "global life quality". The essential predictors of depressive symptoms after transplantation, explained by 81% variations of depression, were weaker "fighting spirit" before transplantation, stronger "anxious preoccupation" after transplantation, worse "global life quality" after transplantation and higher level of anxious and depressive symptoms on admission to hospital. The psychological and pharmacological interventions, which reduce anxiety, depression and "anxious preoccupation" as well as enhance "fighting spirit", should be introduced before BMT to improve the patients' mental state.

Computation of nonlinear least squares estimator and maximum likelihood using principles in matrix calculus

NASA Astrophysics Data System (ADS)

Mahaboob, B.; Venkateswarlu, B.; Sankar, J. Ravi; Balasiddamuni, P.

2017-11-01

This paper uses matrix calculus techniques to obtain Nonlinear Least Squares Estimator (NLSE), Maximum Likelihood Estimator (MLE) and Linear Pseudo model for nonlinear regression model. David Pollard and Peter Radchenko [1] explained analytic techniques to compute the NLSE. However the present research paper introduces an innovative method to compute the NLSE using principles in multivariate calculus. This study is concerned with very new optimization techniques used to compute MLE and NLSE. Anh [2] derived NLSE and MLE of a heteroscedatistic regression model. Lemcoff [3] discussed a procedure to get linear pseudo model for nonlinear regression model. In this research article a new technique is developed to get the linear pseudo model for nonlinear regression model using multivariate calculus. The linear pseudo model of Edmond Malinvaud [4] has been explained in a very different way in this paper. David Pollard et.al used empirical process techniques to study the asymptotic of the LSE (Least-squares estimation) for the fitting of nonlinear regression function in 2006. In Jae Myung [13] provided a go conceptual for Maximum likelihood estimation in his work “Tutorial on maximum likelihood estimation

The ABCs of Depression: Integrating Affective, Biological, and Cognitive Models to Explain the Emergence of the Gender Difference in Depression

ERIC Educational Resources Information Center

Hyde, Janet Shibley; Mezulis, Amy H.; Abramson, Lyn Y.

2008-01-01

In adulthood, twice as many women as men are depressed, a pattern that holds in most nations. In childhood, girls are no more depressed than boys, but more girls than boys are depressed by ages 13 to 15. Although many influences on this emergent gender difference in depression have been proposed, a truly integrated, developmental model is lacking.…

Sources of Variability in Physical Activity Among Inactive People with Multiple Sclerosis.

PubMed

Uszynski, Marcin K; Herring, Matthew P; Casey, Blathin; Hayes, Sara; Gallagher, Stephen; Motl, Robert W; Coote, Susan

2018-04-01

Evidence supports that physical activity (PA) improves symptoms of multiple sclerosis (MS). Although application of principles from Social Cognitive Theory (SCT) may facilitate positive changes in PA behaviour among people with multiple sclerosis (pwMS), the constructs often explain limited variance in PA. This study investigated the extent to which MS symptoms, including fatigue, depression, and walking limitations combined with the SCT constructs, explained more variance in PA than SCT constructs alone among pwMS. Baseline data, including objectively assessed PA, exercise self-efficacy, goal setting, outcome expectations, 6-min walk test, fatigue and depression, from 65 participants of the Step It Up randomized controlled trial completed in Ireland (2016), were included. Multiple regression models quantified variance explained in PA and independent associations of (1) SCT constructs, (2) symptoms and (3) SCT constructs and symptoms. Model 1 included exercise self-efficacy, exercise goal setting and multidimensional outcomes expectations for exercise and explained ~14% of the variance in PA (R 2 =0.144, p < 0.05). Model 2 included walking limitations, fatigue and depression and explained 20% of the variance in PA (R 2 =0.196, p < 0.01). Model 3 combined models 1 and 2 and explained variance increased to ~29% (R 2 =0.288; p<0.01). In Model 3, exercise self-efficacy (β=0.30, p < 0.05), walking limitations (β=0.32, p < 0.01), fatigue (β = -0.41, p < 0.01) and depression (β = 0.34, p < 0.05) were significantly and independently associated with PA. Findings suggest that relevant MS symptoms improved by PA, including fatigue, depression and walking limitations, and SCT constructs together explained more variance in PA than SCT constructs alone, providing support for targeting both SCT constructs and these symptoms in the multifactorial promotion of PA among pwMS.

Nonlinear Analysis of Motor Activity Shows Differences between Schizophrenia and Depression: A Study Using Fourier Analysis and Sample Entropy

PubMed Central

Hauge, Erik R.; Berle, Jan Øystein; Oedegaard, Ketil J.; Holsten, Fred; Fasmer, Ole Bernt

2011-01-01

The purpose of this study has been to describe motor activity data obtained by using wrist-worn actigraphs in patients with schizophrenia and major depression by the use of linear and non-linear methods of analysis. Different time frames were investigated, i.e., activity counts measured every minute for up to five hours and activity counts made hourly for up to two weeks. The results show that motor activity was lower in the schizophrenic patients and in patients with major depression, compared to controls. Using one minute intervals the depressed patients had a higher standard deviation (SD) compared to both the schizophrenic patients and the controls. The ratio between the root mean square successive differences (RMSSD) and SD was higher in the schizophrenic patients compared to controls. The Fourier analysis of the activity counts measured every minute showed that the relation between variance in the low and the high frequency range was lower in the schizophrenic patients compared to the controls. The sample entropy was higher in the schizophrenic patients compared to controls in the time series from the activity counts made every minute. The main conclusions of the study are that schizophrenic and depressive patients have distinctly different profiles of motor activity and that the results differ according to period length analysed. PMID:21297977

The Role of Marital Power in Depression and Marital Distress.

ERIC Educational Resources Information Center

Halloran, Elizabeth C.

1998-01-01

Drawing on sex-role theory, the learned-helplessness model of depression, and a review of empirical research, this article explores inequity in marital power as a potential third variable that explains how depression and the quality of marriage are related. Aims to generate broad-minded thinking about how marital power, depression, and marital…

The Role of Loneliness in the Relationship between Anxiety and Depression in Clinical and School-Based Youth

ERIC Educational Resources Information Center

Ebesutani, Chad; Fierstein, Matthew; Viana, Andres G.; Trent, Lindsay; Young, John; Sprung, Manuel

2015-01-01

Identifying mechanisms that explain the relationship between anxiety and depression are needed. The Tripartite Model is one model that has been proposed to help explain the association between these two problems, positing a shared component called negative affect. The objective of the present study was to examine the role of loneliness in relation…

Predictors of Depression among Seropositive Batswana Men and Women: A Descriptive Correlational Study.

PubMed

Coleman, Christopher Lance

2016-12-01

The purpose of this descriptive correlational study was to describe predictors of depressive symptoms among N=70 seropositive Botswana men and women residing in Gaborne, Botswana. A demographic questionnaire, the Center for Epidemiologic Studies Depression Scale, (CESD-D), and the SF-36 [Quality of life] were administered. The questionnaires were translated and back translated in Setswana and administered by Batswana men and women. The results of the regression analyses resulted in two calculated models. In the first Model energy/fatigue explained 46% of the variance in depressive symptoms (P=.000), and in the second Model energy/fatigue and role limitations on emotional well-being explained 50% of the variance in depressive symptoms respectively. The study findings underscore the need for mental health services for seropositive Batswana men and women. Copyright © 2016 Elsevier Inc. All rights reserved.

Factors in Outcomes of Short-Term Dynamic Psychotherapy for Chronic vs. Nonchronic Major Depression

PubMed Central

LUBORSKY, LESTER; DIGUER, LOUIS; CACCIOLA, JOHN; BARBER, JACQUES P.; MORAS, KARLA; SCHMIDT, KELLY; DERUBEIS, ROBERT J.

1996-01-01

The benefits, and variables influencing the benefits, of short-term dynamic psychotherapy for chronic major depression versus nonchronic major depression were examined for 49 patients. The two diagnostic groups started at the same level on the Beck Depression Inventory (BDI) and Global Assessment of Functioning Scale (GAF) and benefited similarly. The bases for the benefits were examined by linear models explaining 35% of termination BDI variance and 47% of termination GAF scores. By far the largest contributor to outcome was initial GAF, followed by presence of more than one comorbid Axis I diagnosis. Initial level of depression on the BDI was not a significant predictor of termination BDI. The chronic/ nonchronic distinction accounted for less than 1% of explained variance, and little was added by personality disorder, age, or gender. PMID:22700274

Nonlinear excited waves on the interventricular septum

NASA Astrophysics Data System (ADS)

Bekki, Naoaki; Harada, Yoshifumi; Kanai, Hiroshi

2012-11-01

Using a novel ultrasonic noninvasive imaging method, we observe some phase singularities in propagating excited waves on a human cardiac interventricular septum (IVS) for a healthy young male. We present a possible physical model explaining one-dimensional dynamics of phase singularities in nonlinearly excited waves on the IVS. We show that at least one of the observed phase singularities in the excited waves on the IVS can be explained by the Bekki-Nozaki hole solution of the complex Ginzburg-Landau equation without any adjustable parameters. We conclude that the complex Ginzburg-Landau equation is such a suitable model for one-dimensional dynamics of cardiac phase singularities in nonlinearly excited waves on the IVS.

Why Is Past Depression the Best Predictor of Future Depression? Stress Generation as a Mechanism of Depression Continuity in Girls

ERIC Educational Resources Information Center

Rudolph, Karen D.; Flynn, Megan; Abaied, Jamie L.; Groot, Alison; Thompson, Renee

2009-01-01

This study examined whether a transactional interpersonal life stress model helps to explain the continuity in depression over time in girls. Youth (86 girls, 81 boys; M age = 12.41, SD = 1.19) and their caregivers participated in a three-wave longitudinal study. Depression and episodic life stress were assessed with semistructured interviews.…

Borderline personality features in depressed or anxious patients.

PubMed

Distel, Marijn A; Smit, Johannes H; Spinhoven, Philip; Penninx, Brenda W J H

2016-07-30

Anxiety and depression frequently co-occur with borderline personality disorder. Relatively little research examined the presence of borderline personality features and its main domains (affective instability, identity problems, negative relationships and self-harm) in individuals with remitted and current anxiety and depression. Participants with current (n=597) or remitted (n=1115) anxiety and/or depression and healthy controls (n=431) were selected from the Netherlands Study of Depression and Anxiety. Assessments included the Personality Assessment Inventory - Borderline Features Scale and several clinical characteristics of anxiety and depression. Borderline personality features were more common in depression than in anxiety. Current comorbid anxiety and depression was associated with most borderline personality features. Anxiety and depression status explained 29.7% of the variance in borderline personality features and 3.8% (self-harm) to 31% (identity problems) of the variance in the four domains. A large part of the variance was shared between anxiety and depression but both disorders also explained a significant amount of unique variance. The severity of anxiety and depression and the level of daily dysfunctioning was positively associated with borderline personality features. Individuals with a longer duration of anxiety and depression showed more affective instability and identity problems. These findings suggest that patients with anxiety and depression may benefit from an assessment of personality pathology as it may have implications for psychological and pharmacological treatment. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

A Memory Model of Depression: An Analysis of Cognition, Development and Emotion.

ERIC Educational Resources Information Center

Rehm, Lynn P.; Naus, Mary J.

In recent years a number of models of depression have been proposed. Many of them have incorporated cognitive constructs to explain vulnerability, initiation, maintenance, and recovery from depression. In light of the wealth of experimental and clinical knowledge about depression, these models can be seen as having a limited focus and scope.…

Co-occurrence of social anxiety and depression symptoms in adolescence: differential links with implicit and explicit self-esteem?

PubMed

de Jong, P J; Sportel, B E; de Hullu, E; Nauta, M H

2012-03-01

Social anxiety and depression often co-occur. As low self-esteem has been identified as a risk factor for both types of symptoms, it may help to explain their co-morbidity. Current dual process models of psychopathology differentiate between explicit and implicit self-esteem. Explicit self-esteem would reflect deliberate self-evaluative processes whereas implicit self-esteem would reflect simple associations in memory. Previous research suggests that low explicit self-esteem is involved in both social anxiety and depression whereas low implicit self-esteem is only involved in social anxiety. We tested whether the association between symptoms of social phobia and depression can indeed be explained by low explicit self-esteem, whereas low implicit self-esteem is only involved in social anxiety. Adolescents during the first stage of secondary education (n=1806) completed the Revised Child Anxiety and Depression Scale (RCADS) to measure symptoms of social anxiety and depression, the Rosenberg Self-Esteem Scale (RSES) to index explicit self-esteem and the Implicit Association Test (IAT) to measure implicit self-esteem. There was a strong association between symptoms of depression and social anxiety that could be largely explained by participants' explicit self-esteem. Only for girls did implicit self-esteem and the interaction between implicit and explicit self-esteem show small cumulative predictive validity for social anxiety, indicating that the association between low implicit self-esteem and social anxiety was most evident for girls with relatively low explicit self-esteem. Implicit self-esteem showed no significant predictive validity for depressive symptoms. The findings support the view that both shared and differential self-evaluative processes are involved in depression and social anxiety.

The intergenerational production of depression in South Korea: results from a cross-sectional study.

PubMed

Jeong, B G; Veenstra, G

2017-01-13

Although a number of studies have uncovered relationships between parental capital and the manifestation of depression in their children, little is known about the mechanisms that undergird the relationships. This study investigates the intergenerational effects of the cultural and economic capitals of South Korean parents on depressive symptoms in their adult children and the degree to which the capitals of the adult children explain them. We employed nationally representative cross-sectional survey data from the 2006 Korea Welfare Panel Study. A sample of 11,576 adults over thirty years of age was used to investigate the intergenerational production of depression in South Korea. We applied binary logistic regression modelling to the Center for Epidemiological Studies Depression Scale (CES-D). Parental education (institutionalized cultural capital) manifested an independent and statistically significant inverse association with depressive symptoms [OR = 1.680 (95% CI: 1.118-2.523) for men; OR = 2.146 (95% CI: 1484-3.102) for women]. Childhood economic circumstances (economic capital) had an independent and statistically significant inverse association with depressive symptoms among adult women only [OR = 2.009 (95% CI: 1.531-2.635)]. The education of the adult children themselves was strongly associated with depressive symptoms in the expected direction [OR = 4.202 (95% CI: 2.856-6.181) for men; OR = 4.058 (95% CI: 2.824-5.830)] and the most of the association between parental capitals and depressive symptoms was explained by the educational attainment of the children. Receipt of monetary inheritance from parents had a weak but statistically significant association with depression among men [OR = 1.248 (95% CI: 1.041-1.496)] but was unrelated to depression among women. A large portion of the association between respondent education and depressive symptoms was explained by household income. Finally, childhood economic circumstances were associated with depressive symptoms among women over and above the cultural and economic capitals held by the women themselves [OR = 1.608 (95% CI: 2.08-2.139)]. Our study illuminates the importance of the intergenerational transmission of capitals for the development of depressive symptoms among adults in South Korea.

Depressive symptoms and rates of bone loss at the hip in older men.

PubMed

Diem, S J; Harrison, S L; Haney, E; Cauley, J A; Stone, K L; Orwoll, E; Ensrud, K E

2013-01-01

In this prospective cohort study, depressive symptoms were associated with higher rates of bone loss in older men. Poorer performance on physical function tests partly explained the association between depressive symptoms and bone loss, suggesting that efforts to increase exercise and improve physical performance in depressed men may be beneficial. The aim of this study was to ascertain whether depressive symptoms are associated with increased rates of bone loss at the hip in older men. A population-based prospective cohort study of 2,464 community-dwelling men, aged 68 and older, enrolled in the Osteoporosis in Men Sleep Ancillary Study had depressive symptoms assessed by the Geriatric Depression Scale (GDS). Subjects were categorized as depressed if GDS ≥6 at the initial examination. Bone mineral density (BMD) at the hip was measured using dual-energy X-ray absorptiometry at the initial and follow-up examination (average 3.4 years between exams). Use of antidepressant medications was assessed by interview and verified from medication containers at the two examinations. A computerized dictionary was used to categorize type of medication. In a base model adjusted for age, race/ethnicity, and clinic site, the mean total hip BMD decreased 0.70 %/year in 136 men with a GDS score of ≥6 compared to 0.39 %/year in 2,328 men with a GDS score of <6 (p = 0.001). Walking speed and timed chair stand partly explained the association between depressive symptoms and rates of bone loss. Depression, as defined by a score of 6 or greater on the Geriatric Depression Scale, is associated with an increased rate of bone loss at the hip in this cohort of older men. Adjustment for walking speed and timed chair stand attenuated the strength of the association, suggesting that differences in physical functioning do partially explain the observed association.

Stress and the Development of Cognitive Vulnerabilities to Depression Explain Sex Differences in Depressive Symptoms during Adolescence

PubMed Central

Hamilton, Jessica L.; Stange, Jonathan P.; Abramson, Lyn Y.; Alloy, Lauren B.

2014-01-01

Although cognitive vulnerabilities to depression have received considerable empirical support, little research has evaluated the differential development of cognitive vulnerabilities in adolescent girls and boys. The current study examined the role of stressful life events, as well as sex differences in reactivity and exposure to stress, in the development of negative cognitive style and rumination in a multi-wave study of 382 adolescents. Path analyses indicated that interpersonal dependent stress predicted higher prospective levels of negative cognitive styles and rumination. Additionally, girls’ greater exposure to interpersonal dependent stress explained their higher levels of rumination, which accounted for girls’ higher levels of depressive symptoms than boys. These findings suggest that interpersonal dependent stress is a significant risk factor for the formation of cognitive vulnerabilities to depression during adolescence, and that the sex difference in depressive symptoms may result from girls’ greater exposure to interpersonal dependent stress and ruminative response style than boys. PMID:26509106

Mild Depression Detection of College Students: an EEG-Based Solution with Free Viewing Tasks.

PubMed

Li, Xiaowei; Hu, Bin; Shen, Ji; Xu, Tingting; Retcliffe, Martyn

2015-12-01

Depression is a common mental disorder with growing prevalence; however current diagnoses of depression face the problem of patient denial, clinical experience and subjective biases from self-report. By using a combination of linear and nonlinear EEG features in our research, we aim to develop a more accurate and objective approach to depression detection that supports the process of diagnosis and assists the monitoring of risk factors. By classifying EEG features during free viewing task, an accuracy of 99.1%, which is the highest to our knowledge by far, was achieved using kNN classifier to discriminate depressed and non-depressed subjects. Furthermore, through correlation analysis, comparisons of performance on each electrode were discussed on the availability of single channel EEG recording depression detection system. Combined with wearable EEG collecting devices, our method offers the possibility of cost effective wearable ubiquitous system for doctors to monitor their patients with depression, and for normal people to understand their mental states in time.

Theory of cavitons in complex plasmas.

PubMed

Shukla, P K; Eliasson, B; Sandberg, I

2003-08-15

Nonlinear coupling between Langmuir waves with finite amplitude dispersive dust acoustic perturbations is considered. It is shown that the interaction is governed by a pair of coupled nonlinear differential equations. Numerical results reveal the formation of Langmuir envelope solitons composed of the dust density depression created by the ponderomotive force of bell-shaped Langmuir wave envelops. The associated ambipolar potential is positive. The present nonlinear theory should be able to account for the trapping of large amplitude Langmuir waves in finite amplitude dust density holes. This scenario may appear in Saturn's dense rings, and the Cassini spacecraft should be able to observe fully nonlinear cavitons, as presented herein. Furthermore, we propose that new electron-beam plasma experiments should be conducted to verify our theoretical prediction.

Do Parental Stressors and Avoidance Coping Mediate between Parental Depression and Offspring Depression? A 23-Year Follow-Up

ERIC Educational Resources Information Center

Timko, Christine; Cronkite, Ruth C.; Moos, Rudolf H.

2010-01-01

We examined whether parents' stressors and avoidance coping when offspring were children helped to explain associations between parent depression at baseline and offspring's avoidance coping and depression in adulthood. Self-report data were collected at baseline and 1 year from parents (N = 326) and at 23 years from adult offspring (N = 326).…

Is It More Than the Blues? Children Can Suffer from Depression, Too.

ERIC Educational Resources Information Center

Tuscano, Antoinette

2000-01-01

Explains that children be depressed, though they may express it very differently than adults, noting symptoms to watch for; causes of depression; when to seek help; what to do if a child appears depressed; how to talk to a child about what is wrong; and the importance of finding expert help. Sidebars present resources and tips on finding a…

Comparative Pessimism or Optimism: Depressed Mood, Risk-Taking, Social Utility and Desirability.

PubMed

Milhabet, Isabelle; Le Barbenchon, Emmanuelle; Cambon, Laurent; Molina, Guylaine

2015-03-05

Comparative optimism can be defined as a self-serving, asymmetric judgment of the future. It is often thought to be beneficial and socially accepted, whereas comparative pessimism is correlated with depression and socially rejected. Our goal was to examine the social acceptance of comparative optimism and the social rejection of comparative pessimism in two dimensions of social judgment, social desirability and social utility, considering the attributions of dysphoria and risk-taking potential (studies 2 and 3) on outlooks on the future. In three experiments, the participants assessed either one (study 1) or several (studies 2 and 3) fictional targets in two dimensions, social utility and social desirability. Targets exhibiting comparatively optimistic or pessimistic outlooks on the future were presented as non-depressed, depressed, or neither (control condition) (study 1); non-depressed or depressed (study 2); and non-depressed or in control condition (study 3). Two significant results were obtained: (1) social rejection of comparative pessimism in the social desirability dimension, which can be explained by its depressive feature; and (2) comparative optimism was socially accepted on the social utility dimension, which can be explained by the perception that comparatively optimistic individuals are potential risk-takers.

Rumination, anxiety, depressive symptoms and subsequent depression in adolescents at risk for psychopathology: a longitudinal cohort study.

PubMed

Wilkinson, Paul O; Croudace, Tim J; Goodyer, Ian M

2013-10-08

A ruminative style of responding to low mood is associated with subsequent high depressive symptoms and depressive disorder in children, adolescents and adults. Scores on self-report rumination scales correlate strongly with scores on anxiety and depression symptom scales. This may confound any associations between rumination and subsequent depression. Our sample comprised 658 healthy adolescents at elevated risk for psychopathology. This study applied ordinal item (non-linear) factor analysis to pooled items from three self-report questionnaires to explore whether there were separate, but correlated, constructs of rumination, depression and anxiety. It then tested whether rumination independently predicted depressive disorder and depressive symptoms over the subsequent 12 months, after adjusting for confounding variables. We identified a single rumination factor, which was correlated with factors representing cognitive symptoms of depression, somatic symptoms of depression and anxiety symptoms; and one factor representing adaptive responses to low mood. Elevated rumination scores predicted onset of depressive disorders over the subsequent year (p = 0.035), and levels of depressive symptoms 12 months later (p < 0.0005), after adjustment for prior levels of depressive and anxiety symptoms. High rumination predicts onset of depressive disorder in healthy adolescents. Therapy that reduces rumination and increases distraction/problem-solving may reduce onset and relapse rates of depression.

Repetitive negative thinking predicts depression and anxiety symptom improvement during brief cognitive behavioral therapy.

PubMed

Kertz, Sarah J; Koran, Jennifer; Stevens, Kimberly T; Björgvinsson, Thröstur

2015-05-01

Repetitive negative thinking (RNT) is a common symptom across depression and anxiety disorders and preliminary evidence suggests that decreases in rumination and worry are related to improvement in depression and anxiety symptoms. However, despite its prevalence, relatively little is known about transdiagnostic RNT and its temporal associations with symptom improvement during treatment. The current study was designed to examine the influence of RNT on subsequent depression and anxiety symptoms during treatment. Participants (n = 131; 52% female; 93% White; M = 34.76 years) were patients presenting for treatment in a brief, cognitive behavior therapy based, partial hospitalization program. Participants completed multiple assessments of depression (Center for the Epidemiological Studies of Depression-10 scale), anxiety (the 7-item Generalized Anxiety Disorder Scale), and repetitive negative thinking (Perseverative Thinking Questionnaire) over the course of treatment. Results indicated statistically significant between and within person effects of RNT on depression and anxiety, even after controlling for the effect of time, previous symptom levels, referral source, and treatment length. RNT explained 22% of the unexplained variability in depression scores and 15% of the unexplained variability in anxiety scores beyond that explained by the control variables. RNT may be an important transdiagnostic treatment target for anxiety and depression. Copyright © 2015 Elsevier Ltd. All rights reserved.

Associations of Child Sexual and Physical Abuse with Obesity and Depression in Middle-Aged Women

ERIC Educational Resources Information Center

Rohde, Paul; Ichikawa, Laura; Simon, Gregory E.; Ludman, Evette J.; Linde, Jennifer A.; Jeffery, Robert W.; Operskalski, Belinda H.

2008-01-01

Objective: Examine whether (1) childhood maltreatment is associated with subsequent obesity and depression in middle-age; (2) maltreatment explains the associations between obesity and depression; and (3) binge eating or body dissatisfaction mediate associations between childhood maltreatment and subsequent obesity. Methods: Data were obtained…

Can Reporting Heterogeneity Explain Differences in Depressive Symptoms across Europe?

ERIC Educational Resources Information Center

Kok, Renske; Avendano, Mauricio; d'Uva, Teresa Bago; Mackenbach, Johan

2012-01-01

Depression is one of the leading causes of disability in the developed world. Previous studies have shown varying depression prevalence rates between European countries, and also within countries, between socioeconomic groups. However, it is unclear whether these differences reflect true variations in prevalence or whether they are attributable to…

Depressive Symptoms and Cigarette Smoking in a College Sample

ERIC Educational Resources Information Center

Kenney, Brent A.; Holahan, Charles J.

2008-01-01

Objective and Participants: The authors examined (1) the relationship between depressive symptoms and cigarette smoking in a college sample and (2) the role of smoking self-efficacy (one's perceived ability to abstain from smoking) in explaining the relationship between depressive symptoms and cigarette smoking. Methods: Predominantly first-year…

Visuo-manual tracking: does intermittent control with aperiodic sampling explain linear power and non-linear remnant without sensorimotor noise?

PubMed

Gollee, Henrik; Gawthrop, Peter J; Lakie, Martin; Loram, Ian D

2017-11-01

A human controlling an external system is described most easily and conventionally as linearly and continuously translating sensory input to motor output, with the inevitable output remnant, non-linearly related to the input, attributed to sensorimotor noise. Recent experiments show sustained manual tracking involves repeated refractoriness (insensitivity to sensory information for a certain duration), with the temporary 200-500 ms periods of irresponsiveness to sensory input making the control process intrinsically non-linear. This evidence calls for re-examination of the extent to which random sensorimotor noise is required to explain the non-linear remnant. This investigation of manual tracking shows how the full motor output (linear component and remnant) can be explained mechanistically by aperiodic sampling triggered by prediction error thresholds. Whereas broadband physiological noise is general to all processes, aperiodic sampling is associated with sensorimotor decision making within specific frontal, striatal and parietal networks; we conclude that manual tracking utilises such slow serial decision making pathways up to several times per second. The human operator is described adequately by linear translation of sensory input to motor output. Motor output also always includes a non-linear remnant resulting from random sensorimotor noise from multiple sources, and non-linear input transformations, for example thresholds or refractory periods. Recent evidence showed that manual tracking incurs substantial, serial, refractoriness (insensitivity to sensory information of 350 and 550 ms for 1st and 2nd order systems respectively). Our two questions are: (i) What are the comparative merits of explaining the non-linear remnant using noise or non-linear transformations? (ii) Can non-linear transformations represent serial motor decision making within the sensorimotor feedback loop intrinsic to tracking? Twelve participants (instructed to act in three prescribed ways) manually controlled two systems (1st and 2nd order) subject to a periodic multi-sine disturbance. Joystick power was analysed using three models, continuous-linear-control (CC), continuous-linear-control with calculated noise spectrum (CCN), and intermittent control with aperiodic sampling triggered by prediction error thresholds (IC). Unlike the linear mechanism, the intermittent control mechanism explained the majority of total power (linear and remnant) (77-87% vs. 8-48%, IC vs. CC). Between conditions, IC used thresholds and distributions of open loop intervals consistent with, respectively, instructions and previous measured, model independent values; whereas CCN required changes in noise spectrum deviating from broadband, signal dependent noise. We conclude that manual tracking uses open loop predictive control with aperiodic sampling. Because aperiodic sampling is inherent to serial decision making within previously identified, specific frontal, striatal and parietal networks we suggest that these structures are intimately involved in visuo-manual tracking. © 2017 The Authors. The Journal of Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.

Comorbidity between depression and inflammatory bowel disease explained by immune-inflammatory, oxidative, and nitrosative stress; tryptophan catabolite; and gut-brain pathways.

PubMed

Martin-Subero, Marta; Anderson, George; Kanchanatawan, Buranee; Berk, Michael; Maes, Michael

2016-04-01

The nature of depression has recently been reconceptualized, being conceived as the clinical expression of activated immune-inflammatory, oxidative, and nitrosative stress (IO&NS) pathways, including tryptophan catabolite (TRYCAT), autoimmune, and gut-brain pathways. IO&NS pathways are similarly integral to the pathogenesis of inflammatory bowel disease (IBD). The increased depression prevalence in IBD associates with a lower quality of life and increased morbidity in IBD, highlighting the role of depression in modulating the pathophysiology of IBD.This review covers data within such a wider conceptualization that better explains the heightened co-occurrence of IBD and depression. Common IO&NS underpinning between both disorders is evidenced by increased pro-inflammatory cytokine levels, eg, interleukin-1 (IL-1) and tumor necrosis factor-α, IL-6 trans-signalling; Th-1- and Th-17-like responses; neopterin and soluble IL-2 receptor levels; positive acute phase reactants (haptoglobin and C-reactive protein); lowered levels of negative acute phase reactants (albumin, transferrin, zinc) and anti-inflammatory cytokines (IL-10 and transforming growth factor-β); increased O&NS with damage to lipids, proteinsm and DNA; increased production of nitric oxide (NO) and inducible NO synthase; lowered plasma tryptophan but increased TRYCAT levels; autoimmune responses; and increased bacterial translocation. As such, heightened IO&NS processes in depression overlap with the biological underpinnings of IBD, potentially explaining their increased co-occurrence. This supports the perspective that there is a spectrum of IO&NS disorders that includes depression, both as an emergent comorbidity and as a contributor to IO&NS processes. Such a frame of reference has treatment implications for IBD when "comorbid" with depression.

Neighborhood matters: the impact of Hispanic ethnic density on future depressive symptoms 1-year following an ACS event among Hispanic patients.

PubMed

Denton, Ellen-Ge D; Shaffer, Jonathan A; Alcantara, Carmela; Cadermil, Esteban

2016-02-01

The Ethnic Density hypothesis posits that living around others from similar ethnic backgrounds reduces the risk of adverse mental health outcomes such as depression. Contrary to this hypothesis, previous work has shown that Hispanic ethnic density is cross-sectionally associated with increased depressive symptom severity among patients hospitalized with an acute coronary syndrome (ACS; myocardial infarction or unstable angina pectoris). To date, no study has examined the prospective association of Hispanic ethnic density on long-term depressive symptom severity following an acute medical event. We prospectively assessed the impact of Hispanic ethnic density on depressive symptoms, 1-year following an ACS event, among Hispanic adult patients. We tested the non-linear association between ethnic density and depressive symptoms to account for inconsistent findings on the ethnic density hypothesis. At the time of an index ACS event (i.e., baseline, N = 326) and 1-year later (N = 252), Hispanic patients from the Prescription Usage, Lifestyle, and Stress Evaluation prospective cohort study completed the Beck Depression Inventory as a measure of depressive symptom severity. Hispanic ethnic density was defined by the percentage of Hispanic residents within each patient's census tract using data extracted from the American Community Survey Census (2010-2013). Covariates included baseline demographic factors (age, gender, English fluency, education, nativity status), cardiovascular factors (Charlson comorbidity index, left ventricular ejection fraction, Global Registry of Acute Coronary Events 6-month prognostic risk score), and neighborhood factors (residential density, income, and percentage of households receiving public assistance). In an adjusted multivariable linear regression analysis there was a significant curvilinear association between Hispanic ethnic density and depressive symptom severity at 1 year. As Hispanic ethnic density increased from low to moderate density, there was an increase in depressive symptoms, but depressive symptoms slightly declined in census tracts with the highest density of Hispanics. Furthermore, gender significantly moderated the relation between Hispanic ethnic density and 1-year depressive symptom severity, such that Hispanic ethnic density was significantly associated with increased depressive symptom severity for female Hispanic patients with ACS, but not for male Hispanic patients. Previous research suggests that ethnic density may be protective against depression in Hispanic enclaves; however, our findings suggest a non-linear ethnic density effect and an overall more complex association between ethnic density and depression. These data add to a growing body of literature on the effects of sociodemographic and contextual factors on health.

Neighborhood matters: the impact of Hispanic ethnic density on future depressive symptoms 1-year following an ACS event among Hispanic patients

PubMed Central

Denton, Ellen-ge D.; Shaffer, Jonathan A.; Alcantara, Carmela; Cadermil, Esteban

2015-01-01

The Ethnic Density hypothesis posits that living around others from similar ethnic backgrounds reduces the risk of adverse mental health outcomes such as depression. Contrary to this hypothesis, previous work has shown that Hispanic ethnic density is cross-sectionally associated with increased depressive symptom severity among patients hospitalized with an acute coronary syndrome (ACS; myocardial infarction or unstable angina pectoris). To date, no study has examined the prospective association of Hispanic ethnic density on long-term depressive symptom severity following an acute medical event. We prospectively assessed the impact of Hispanic ethnic density on depressive symptoms, 1-year following an ACS event, among Hispanic adult patients. We tested the non-linear association between ethnic density and depressive symptoms to account for inconsistent findings on the ethnic density hypothesis. At the time of an index ACS event (i.e., baseline, N = 326) and 1-year later (N = 252), Hispanic patients from the Prescription Usage, Lifestyle, and Stress Evaluation prospective cohort study completed the Beck Depression Inventory as a measure of depressive symptom severity. Hispanic ethnic density was defined by the percentage of Hispanic residents within each patient's census tract using data extracted from the American Community Survey Census (2010–2013). Covariates included baseline demographic factors (age, gender, English fluency, education, nativity status), cardiovascular factors (Charlson comorbidity index, left ventricular ejection fraction, Global Registry of Acute Coronary Events 6-month prognostic risk score), and neighborhood factors (residential density, income, and percentage of households receiving public assistance). In an adjusted multivariable linear regression analysis there was a significant curvilinear association between Hispanic ethnic density and depressive symptom severity at 1 year. As Hispanic ethnic density increased from low to moderate density, there was an increase in depressive symptoms, but depressive symptoms slightly declined in census tracts with the highest density of Hispanics. Furthermore, gender significantly moderated the relation between Hispanic ethnic density and 1-year depressive symptom severity, such that Hispanic ethnic density was significantly associated with increased depressive symptom severity for female Hispanic patients with ACS, but not for male Hispanic patients. Previous research suggests that ethnic density may be protective against depression in Hispanic enclaves; however, our findings suggest a non-linear ethnic density effect and an overall more complex association between ethnic density and depression. These data add to a growing body of literature on the effects of sociodemographic and contextual factors on health. PMID:26407692

Investigation of cloud condensation nuclei properties and droplet growth kinetics of the water-soluble aerosol fraction in Mexico City

NASA Astrophysics Data System (ADS)

Padró, Luz T.; Tkacik, Daniel; Lathem, Terry; Hennigan, Chris J.; Sullivan, Amy P.; Weber, Rodney J.; Huey, L. Greg; Nenes, Athanasios

2010-05-01

We present hygroscopic and cloud condensation nuclei (CCN) relevant properties of the water-soluble fraction of Mexico City aerosol collected upon filters during the 2006 Megacity Initiative: Local and Global Research Observations (MILAGRO) campaign. Application of κ-Köhler theory to the observed CCN activity gave a fairly constant hygroscopicity parameter (κ = 0.28 ± 0.06) regardless of location and organic fraction. Köhler theory analysis was used to understand this invariance by separating the molar volume and surfactant contributions to the CCN activity. Organics were found to depress surface tension (10-15%) from that of pure water. Daytime samples exhibited lower molar mass (˜200 amu) and surface tension depression than nighttime samples (˜400 amu); this is consistent with fresh hygroscopic secondary organic aerosol (SOA) condensing onto particles during peak photochemical hours, subsequently aging during nighttime periods of high relative humidity. Changes in surface tension partially compensate for shifts in average molar volume to give the constant hygroscopicity observed, which implies the amount (volume fraction) of soluble material in the parent aerosol is the key composition parameter required for CCN predictions. This finding, if applicable elsewhere, may explain why CCN predictions are often found to be insensitive to assumptions of chemical composition and provides a very simple way to parameterize organic hygroscopicity in atmospheric models (i.e., κorg = 0.28ɛWSOC). Special care should be given, however, to surface tension depression from organic surfactants, as its nonlinear dependence with organic fraction may introduce biases in observed (and predicted) hygroscopicity. Finally, threshold droplet growth analysis suggests the water-soluble organics do not affect activation kinetics.

Actigraphic assessment of motor activity in acutely admitted inpatients with bipolar disorder.

PubMed

Krane-Gartiser, Karoline; Henriksen, Tone Elise Gjotterud; Morken, Gunnar; Vaaler, Arne; Fasmer, Ole Bernt

2014-01-01

Mania is associated with increased activity, whereas psychomotor retardation is often found in bipolar depression. Actigraphy is a promising tool for monitoring phase shifts and changes following treatment in bipolar disorder. The aim of this study was to compare recordings of motor activity in mania, bipolar depression and healthy controls, using linear and nonlinear analytical methods. Recordings from 18 acutely hospitalized inpatients with mania were compared to 12 recordings from bipolar depression inpatients and 28 healthy controls. 24-hour actigraphy recordings and 64-minute periods of continuous motor activity in the morning and evening were analyzed. Mean activity and several measures of variability and complexity were calculated. Patients with depression had a lower mean activity level compared to controls, but higher variability shown by increased standard deviation (SD) and root mean square successive difference (RMSSD) over 24 hours and in the active morning period. The patients with mania had lower first lag autocorrelation compared to controls, and Fourier analysis showed higher variance in the high frequency part of the spectrum corresponding to the period from 2-8 minutes. Both patient groups had a higher RMSSD/SD ratio compared to controls. In patients with mania we found an increased complexity of time series in the active morning period, compared to patients with depression. The findings in the patients with mania are similar to previous findings in patients with schizophrenia and healthy individuals treated with a glutamatergic antagonist. We have found distinctly different activity patterns in hospitalized patients with bipolar disorder in episodes of mania and depression, assessed by actigraphy and analyzed with linear and nonlinear mathematical methods, as well as clear differences between the patients and healthy comparison subjects.

Actigraphic Assessment of Motor Activity in Acutely Admitted Inpatients with Bipolar Disorder

PubMed Central

Krane-Gartiser, Karoline; Henriksen, Tone Elise Gjotterud; Morken, Gunnar; Vaaler, Arne; Fasmer, Ole Bernt

2014-01-01

Introduction Mania is associated with increased activity, whereas psychomotor retardation is often found in bipolar depression. Actigraphy is a promising tool for monitoring phase shifts and changes following treatment in bipolar disorder. The aim of this study was to compare recordings of motor activity in mania, bipolar depression and healthy controls, using linear and nonlinear analytical methods. Materials and Methods Recordings from 18 acutely hospitalized inpatients with mania were compared to 12 recordings from bipolar depression inpatients and 28 healthy controls. 24-hour actigraphy recordings and 64-minute periods of continuous motor activity in the morning and evening were analyzed. Mean activity and several measures of variability and complexity were calculated. Results Patients with depression had a lower mean activity level compared to controls, but higher variability shown by increased standard deviation (SD) and root mean square successive difference (RMSSD) over 24 hours and in the active morning period. The patients with mania had lower first lag autocorrelation compared to controls, and Fourier analysis showed higher variance in the high frequency part of the spectrum corresponding to the period from 2–8 minutes. Both patient groups had a higher RMSSD/SD ratio compared to controls. In patients with mania we found an increased complexity of time series in the active morning period, compared to patients with depression. The findings in the patients with mania are similar to previous findings in patients with schizophrenia and healthy individuals treated with a glutamatergic antagonist. Conclusion We have found distinctly different activity patterns in hospitalized patients with bipolar disorder in episodes of mania and depression, assessed by actigraphy and analyzed with linear and nonlinear mathematical methods, as well as clear differences between the patients and healthy comparison subjects. PMID:24586883

Relationships of diabetes-specific emotional distress, depression, anxiety, and overall well-being with HbA1c in adult persons with type 1 diabetes.

PubMed

Strandberg, Ragnhild Bjarkøy; Graue, Marit; Wentzel-Larsen, Tore; Peyrot, Mark; Rokne, Berit

2014-09-01

Emotional problems are common in adults with diabetes, and knowledge about how different indicators of emotional problems are related with glycemic control is required. The aim was to examine the relationships of diabetes-specific emotional distress, depression, anxiety, and overall well-being with glycosylated hemoglobin (HbA1c). Of the 319 adults with type 1 diabetes attending the endocrinology outpatient clinic at a university hospital in Norway, 235 (74%) completed the Diabetes Distress Scale, the Problem Areas in Diabetes Survey, the Hospital Anxiety and Depression Scale, and the World Health Organization-Five Well-Being Index. Blood samples were taken at the time of data collection to determine HbA1c. Regression analyses examined associations of diabetes-specific emotional distress, anxiety, depression, and overall well-being with HbA1c. The relationship between diabetes-specific emotional distress and HbA1c was tested for nonlinearity. Diabetes-specific emotional distress was related to glycemic control (DDS total: unstandardized coefficient=0.038, P<.001; PAID total: coefficient=0.021, P=.007), but depression, anxiety, and overall well-being were not. On the DDS, only regimen-related distress was independently related to HbA1c (coefficient=0.056, P<.001). A difference of 0.5 standard deviation of baseline regimen distress is associated with a difference of 0.6 in HbA1c. No significant nonlinearity was detected in the relationship between diabetes-specific distress and HbA1c. To stimulate adequate care strategies, health personnel should acknowledge depression and diabetes-specific emotional distress as different conditions in clinical consultations. Addressing diabetes-specific emotional distress, in particular regimen distress, in clinical consultation might improve glycemic control. Copyright © 2014. Published by Elsevier Inc.

Nonlinear dynamics behavior analysis of the spatial configuration of a tendril-bearing plant

NASA Astrophysics Data System (ADS)

Feng, Jingjing; Zhang, Qichang; Wang, Wei; Hao, Shuying

2017-03-01

Tendril-bearing plants appear to have a spiraling shape when tendrils climb along a support during growth. The growth characteristics of a tendril-bearer can be simplified to a model of a thin elastic rod with a cylindrical constraint. In this paper, the connection between some typical configuration characteristics of tendrils and complex nonlinear dynamic behavior are qualitatively analyzed. The space configuration problem of tendrils can be explained through the study of the nonlinear dynamic behavior of the thin elastic rod system equation. In this study, the complex non-Z2 symmetric critical orbits in the system equation under critical parameters were presented. A new function transformation method that can effectively maintain the critical orbit properties was proposed, and a new nonlinear differential equations system containing complex nonlinear terms can been obtained to describe the cross section position and direction of a rod during climbing. Numerical simulation revealed that the new system can describe the configuration of a rod with reasonable accuracy. To adequately explain the growing regulation of the rod shape, the critical orbit and configuration of rod are connected in a direct way. The high precision analytical expressions of these complex non-Z2 symmetric critical orbits are obtained by introducing a suitable analytical method, and then these expressions are used to draw the corresponding three-dimensional configuration figures of an elastic thin rod. Combined with actual tendrils on a live plant, the space configuration of the winding knots of tendril is explained by the concept of heteroclinic orbit from the perspective of nonlinear dynamics, and correctness of the theoretical analysis was verified. This theoretical analysis method could also be effectively applied to other similar slender structures.

Introduction to nonlinear acoustics

NASA Astrophysics Data System (ADS)

Bjørnø, Leif

2010-01-01

A brief review of the basic principles of fluid mechanics needed for development of linear and nonlinear ultrasonic concepts will be given. The fundamental equations of nonlinear ultrasonics will be derived and their physical properties explained. It will be shown how an originally monochromatic finite-amplitude ultrasonic wave, due to nonlinear effects, will distort during its propagation in time and space to form higher harmonics to its fundamental frequency. The concepts of shock formation will be presented. The material nonlinearity, described by the nonlinearity parameter B/A of the material, and the convective nonlinearity, described by the ultrasonic Mach Number, will be explained. Two procedures for determination of B/A will briefly be described and some B/A-values characterizing biological materials will be presented. Shock formation, described by use of the Goldberg Number,and Ultrasonic Saturation will be discussed.. An introduction to focused ultrasonic fields will be given and it will be shown how the ultrasonic intensity will vary axially and laterally in and near the focal region and how the field parameters of interest to biomedical applications may be described by use of the KZK-Model. Finally, an introduction will be given to the parametric acoustic array formed by mixing and interaction of two monochromatic, finite-amplitude ultrasonic waves in a liquid and the potentials of this mixing process in biomedical ultrasound will briefly be mentioned.

When Depression Mediates the Relationship between Entity Beliefs and Performance

ERIC Educational Resources Information Center

Da Fonseca, David; Cury, Francois; Santos, Andreia; Payen, Vincent; Bounoua, Lenda; Brisswalter, Jeannick; Rufo, Marcel; Poinso, Francois; Deruelle, Christine

2009-01-01

The aim of this study was to determine whether depression can explain the negative relationship between academic performance and the belief that intelligence is a fixed trait, i.e., entity belief. A sample of 353 French volunteer adolescents (age 11-16) completed questionnaires assessing entity theory and depressive symptoms (Children Depression…

Age and Gender Differences in Depression across Adolescence: Real or "Bias"?

ERIC Educational Resources Information Center

van Beek, Yolanda; Hessen, David J.; Hutteman, Roos; Verhulp, Esmee E.; van Leuven, Mirande

2012-01-01

Background: Since developmental psychologists are interested in explaining age and gender differences in depression across adolescence, it is important to investigate to what extent these observed differences can be attributed to measurement bias. Measurement bias may arise when the phenomenology of depression varies with age or gender, i.e., when…

Stress and Emotional Reactivity as Explanations for Gender Differences in Adolescents' Depressive Symptoms

ERIC Educational Resources Information Center

Charbonneau, Anna M.; Mezulis, Amy H.; Hyde, Janet Shibley

2009-01-01

In this longitudinal study, we examined whether certain types of stressful events and how individuals respond to these events would explain gender differences in depressive symptoms among adolescents. We hypothesized that certain stressful events would mediate the relationship between gender and depressive symptoms. We also hypothesized that…

Book review: Nonlinear ocean waves and the inverse scattering transform

USGS Publications Warehouse

Geist, Eric L.

2011-01-01

Nonlinear Ocean Waves and the Inverse Scattering Transform is a comprehensive examination of ocean waves built upon the theory of nonlinear Fourier analysis. The renowned author, Alfred R. Osborne, is perhaps best known for the discovery of internal solitons in the Andaman Sea during the 1970s. In this book, he provides an extensive treatment of nonlinear water waves based on a nonlinear spectral theory known as the inverse scattering transform. The writing is exceptional throughout the book, which is particularly useful in explaining some of the more difficult mathematical concepts.  Review info: Nonlinear Ocean Waves and the Inverse Scattering Transform. By Alfred R. Osborne, 2010. ISBN: 978-125286299, 917 pp.

The role of peri-traumatic stress and disruption distress in predicting symptoms of major depression following exposure to a natural disaster.

PubMed

Bell, Caroline J; Boden, Joseph M; Horwood, L John; Mulder, Roger T

2017-07-01

Few studies have examined the contribution of specific disaster-related experiences to symptoms of depression. The aims of this study were to do this by examining the roles of peri-traumatic stress and distress due to lingering disaster-related disruption in explaining linkages between disaster exposure and major depressive disorder symptoms among a cohort exposed to the 2010-2011 Canterbury (New Zealand) earthquakes. Structural equation models were fitted to data obtained from the Christchurch Health and Development Study at age 35 ( n = 495), 20-24 months following the onset of the disaster. Measures included earthquake exposure, peri-traumatic stress, disruption distress and symptoms of major depressive disorder. The associations between earthquake exposure and major depression were explained largely by the experience of peri-traumatic stress during the earthquakes (β = 0.180, p < 0.01) and not by disruption distress following the earthquakes (β = 0.048, p = 0.47). The results suggest that peri-traumatic stress has been under-recognised as a predictor of major depressive disorder.

Childhood Depression: Relation to Adaptive, Clinical and Predictor Variables

PubMed Central

Garaigordobil, Maite; Bernarás, Elena; Jaureguizar, Joana; Machimbarrena, Juan M.

2017-01-01

The study had two goals: (1) to explore the relations between self-assessed childhood depression and other adaptive and clinical variables (2) to identify predictor variables of childhood depression. Participants were 420 students aged 7–10 years old (53.3% boys, 46.7% girls). Results revealed: (1) positive correlations between depression and clinical maladjustment, school maladjustment, emotional symptoms, internalizing and externalizing problems, problem behaviors, emotional reactivity, and childhood stress; and (2) negative correlations between depression and personal adaptation, global self-concept, social skills, and resilience (sense of competence and affiliation). Linear regression analysis including the global dimensions revealed 4 predictors of childhood depression that explained 50.6% of the variance: high clinical maladjustment, low global self-concept, high level of stress, and poor social skills. However, upon introducing the sub-dimensions, 9 predictor variables emerged that explained 56.4% of the variance: many internalizing problems, low family self-concept, high anxiety, low responsibility, low personal self-assessment, high social stress, few aggressive behaviors toward peers, many health/psychosomatic problems, and external locus of control. The discussion addresses the importance of implementing prevention programs for childhood depression at early ages. PMID:28572787

Childhood abuse and late-life depression: Mediating effects of psychosocial factors for early- and late-onset depression.

PubMed

Wielaard, Ilse; Hoyer, Mathijs; Rhebergen, Didi; Stek, Max L; Comijs, Hannie C

2018-03-01

Childhood abuse makes people vulnerable to developing depression, even in late life. Psychosocial factors that are common in late life, such as loneliness or lack of a partner, may explain this association. Our aim was to investigate whether the association between childhood abuse and depression in older adults can be explained by psychosocial factors. Cross-sectional data were derived from the Netherlands Study of Depression in Older Persons (aged 60-93), including 132 without lifetime depression, 242 persons with an early-onset depression (<60 years), and 125 with a late-onset (≥60 years) depression. Childhood abuse (yes/no) and a frequency-based childhood abuse index were included. Multinomial regression and multivariable mediation analyses were used to examine the association between childhood abuse and the onset of depression, and the influence of loneliness, social network, and partner status. Multinomial regression analyses showed a significant association between childhood abuse and the childhood abuse index with early- and late-onset depression. Multivariable mediation analyses showed that the association between childhood abuse and early-onset depression was partly mediated by social network size and loneliness. This was particularly present for emotional neglect and psychological abuse, but not for physical and sexual abuse. No psychosocial mediators were found for the association between childhood abuse and late-onset depression. A smaller social network and feelings of loneliness mediate the association between childhood abuse and early-onset depression in older adults. Our findings show the importance of detecting childhood abuse as well as the age at depression onset and mapping of relevant psychosocial factors in the treatment of late-life depression. Copyright © 2018 John Wiley & Sons, Ltd.

Loss of Resources and Hurricane Experience as Predictors of Postpartum Depression Among Women in Southern Louisiana

PubMed Central

Ehrlich, Matthew; Xiong, Xu; Buekens, Pierre; Pridjian, Gabriella; Elkind-Hirsch, Karen

2010-01-01

Abstract Background After a natural disaster, mental disorders often become a long-term public health concern. Previous studies under smaller-scale natural disaster conditions suggest loss of psychosocial resources is associated with psychological distress. Methods We examined the occurrence of depression 6 and 12 months postpartum among 208 women residing in New Orleans and Baton Rouge, Louisiana, who were pregnant during or immediately after Hurricane Katrina's landfall. Based on the Conservation of Resources (COR) theory, we explored the contribution of both tangible/financial and nontangible (psychosocial) loss of resources (LOR) on the outcome of depression, measured using the Edinburgh Postnatal Depression Scale (EPDS). We also investigated the influence on depression of individuals' hurricane experience through a Hurricane Experience Score (HES) that includes such factors as witnessing death, contact with flood waters, and injury to self or family members. Results Both tangible and nontangible LOR were associated with depression cross-sectionally and prospectively. Severe hurricane exposure (high HES) was also associated with depression. Regression analysis showed LOR-associated depression was explained almost entirely by nontangible rather than tangible factors. Consistent with COR theory, however, nontangible LOR explained some of the association between severe hurricane exposure and depression in our models. A similar result was seen prospectively for depression at 12 months, even controlling for depression symptoms at 6 months. Conclusions These results suggest the need for preventive measures aimed at preserving psychosocial resources to reduce the long-term effects of disasters. PMID:20438305

Superconducting nanowires as nonlinear inductive elements for qubits

NASA Astrophysics Data System (ADS)

Ku, Jaseung; Manucharyan, Vladimir; Bezryadin, Alexey

2011-03-01

We report microwave transmission measurements of superconducting Fabry-Perot resonators, having a superconducting nanowire placed at a supercurrent antinode. As the plasma oscillation is excited, the supercurrent is forced to flow through the nanowire. The microwave transmission of the resonator-nanowire device shows a nonlinear resonance behavior, significantly dependent on the amplitude of the supercurrent oscillation. We show that such amplitude-dependent response is due to the nonlinearity of the current-phase relationship of the nanowire. The results are explained within a nonlinear oscillator model of the Duffing oscillator, in which the nanowire acts as a purely inductive element, in the limit of low temperatures and low amplitudes. The low-quality factor sample exhibits a ``crater'' at the resonance peak at higher driving power, which is due to dissipation. We observe a hysteretic bifurcation behavior of the transmission response to frequency sweep in a sample with a higher quality factor. The Duffing model is used to explain the Duffing bistability diagram. NSF DMR-1005645, DOE DO-FG02-07ER46453.

Temperament and character profiles associated with depression and treatment response in patients with or without comorbid substance abuse.

PubMed

Paavonen, Vesa; Luoto, Kaisa; Koivukangas, Antti; Lassila, Antero; Leinonen, Esa; Kampman, Olli

2016-11-30

There is limited knowledge on the relationship between temperament and character profiles and substance abuse comorbidity in depressed patients. We recruited 127 depressed patients without alcohol use problems (non-AUP) and 89 depressed patients with alcohol use problems (AUP). We assessed all patients using the Temperament and Character Inventory (TCI-R) at baseline and after 6 weeks of treatment. Using univariate general linear models (GLMs), we analyzed differences in TCI-R between AUP and non-AUP. GLMs were also used in analyzing the associations between TCI-R changes and antidepressive treatment responses measured with changes in Montgomery Åsberg Depression Rating Scale score (ΔMADRS). Alcohol use explained independently significant proportions of the variation in Novelty Seeking, Self-Directedness, and Persistence. Reward Dependence score change explained 14.1% of the ΔMADRS in AUP, but was non-significant in non-AUP. Character score changes in Self-Directedness and Self-Transcendence explained together 14.1% of ΔMADRS in non-AUP, whereas they were all non-significant in AUP. AUP compared with non-AUP patients had lower Self-Directedness and Persistence and higher Novelty Seeking scores. Detected changes in Reward Dependence and lower Self-Directedness in AUP patients could be reflective of different biological mechanisms associated with depressive symptomatology in alcohol abuse. Changes in character are associated with acute treatment response in non-AUP. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Anxiety, depression and autonomy-connectedness: The mediating role of alexithymia and assertiveness.

PubMed

Rutten, Elisabeth A P; Bachrach, Nathan; van Balkom, Anton J L M; Braeken, Johan; Ouwens, Machteld A; Bekker, Marrie H J

2016-12-01

Autonomy-connectedness (self-awareness, sensitivity to others, and capacity for managing new situations) reflects the capacity for self-governance, including in social relationships. Evidence showed that autonomy-connectedness is related to anxiety and depression. Little is known about the underlying mechanisms. We hypothesized that alexithymia and assertiveness would mediate the relationships between autonomy-connectedness and anxiety and depression. Relationships among the variables were investigated in 100 patients with a mean age of 42.2 suffering from anxiety and/or depression using a cross-sectional design. The relationship between self-awareness and both anxiety and depression was mediated by alexithymia. For anxiety, there was also a direct effect of sensitivity to others that was not explained by either alexithymia or assertiveness. Assertiveness did not have any mediational effect. The results indicate that particularly alexithymia explains the association of autonomy-connectedness with anxiety and depression. The study confirmed the relevance of autonomy-connectedness in anxiety and depression. In treating symptoms of anxiety, it is advisable to give attention to normalizing the patient's sensitivity to others. Treatment of patients with symptoms of anxiety and depression should include assessment of emotional awareness and, in the case of impaired emotional awareness, should be tailored as to promote increased awareness. © 2015 The British Psychological Society.

Rumination, anxiety, depressive symptoms and subsequent depression in adolescents at risk for psychopathology: a longitudinal cohort study

PubMed Central

2013-01-01

Background A ruminative style of responding to low mood is associated with subsequent high depressive symptoms and depressive disorder in children, adolescents and adults. Scores on self-report rumination scales correlate strongly with scores on anxiety and depression symptom scales. This may confound any associations between rumination and subsequent depression. Methods Our sample comprised 658 healthy adolescents at elevated risk for psychopathology. This study applied ordinal item (non-linear) factor analysis to pooled items from three self-report questionnaires to explore whether there were separate, but correlated, constructs of rumination, depression and anxiety. It then tested whether rumination independently predicted depressive disorder and depressive symptoms over the subsequent 12 months, after adjusting for confounding variables. Results We identified a single rumination factor, which was correlated with factors representing cognitive symptoms of depression, somatic symptoms of depression and anxiety symptoms; and one factor representing adaptive responses to low mood. Elevated rumination scores predicted onset of depressive disorders over the subsequent year (p = 0.035), and levels of depressive symptoms 12 months later (p < 0.0005), after adjustment for prior levels of depressive and anxiety symptoms. Conclusion High rumination predicts onset of depressive disorder in healthy adolescents. Therapy that reduces rumination and increases distraction/problem-solving may reduce onset and relapse rates of depression. PMID:24103296

Parent Mindfulness and Child Outcome: The Roles of Parent Depressive Symptoms and Parenting.

PubMed

Parent, Justin; Garai, Emily; Forehand, Rex; Roland, Erin; Potts, Jennifer; Haker, Kelly; Champion, Jennifer E; Compas, Bruce E

2011-01-01

The purpose of this study was to examine pathways in a model which proposed associations among parent mindfulness, parent depressive symptoms, two types of parenting, and child problem behavior. Participants' data were from the baseline assessment of a NIMH-sponsored Family-Group Cognitive-Behavioral intervention program (FGCB) for the prevention of child and adolescent depression (Compas et al., 2009). Participants consisted of 145 mothers and 17 fathers (mean age = 41.89 yrs, SD = 7.73) with a history of depression and 211 children (106 males) (mean age = 11.49 yrs, SD = 2.00). Analyses showed that (a) positive parenting appears to play a significant role in helping explain how parent depressive symptoms relate to child externalizing problems and (b) mindfulness is related to child internalizing and externalizing problems; however, the intervening constructs examined did not appear to help explain the mindfulness-child problem behavior associations. Suggestions for future research on parent mindfulness and child problem outcome are described.

Parent Mindfulness and Child Outcome: The Roles of Parent Depressive Symptoms and Parenting

PubMed Central

Parent, Justin; Garai, Emily; Roland, Erin; Potts, Jennifer; Haker, Kelly; Champion, Jennifer E.; Compas, Bruce E.

2011-01-01

The purpose of this study was to examine pathways in a model which proposed associations among parent mindfulness, parent depressive symptoms, two types of parenting, and child problem behavior. Participants’ data were from the baseline assessment of a NIMH-sponsored Family-Group Cognitive-Behavioral intervention program (FGCB) for the prevention of child and adolescent depression (Compas et al., 2009). Participants consisted of 145 mothers and 17 fathers (mean age = 41.89 yrs, SD = 7.73) with a history of depression and 211 children (106 males) (mean age = 11.49 yrs, SD = 2.00). Analyses showed that (a) positive parenting appears to play a significant role in helping explain how parent depressive symptoms relate to child externalizing problems and (b) mindfulness is related to child internalizing and externalizing problems; however, the intervening constructs examined did not appear to help explain the mindfulness-child problem behavior associations. Suggestions for future research on parent mindfulness and child problem outcome are described. PMID:21572927

[Depression and neuroplasticity. Interaction of nervous, endocrine and immune systems].

PubMed

Cassano, Paola; Argibay, Pablo

2010-01-01

Clinical depression is a physical and psychic disease that has neuropathological basis, although the clear understanding of its ethiopathology is still missing. There is evidence of a genetic component in depression, however, the participation of environment is crucial. Stress plays an essential role in the onset of depression. The interaction and the response of the endocrine system with the immune and nervous system are altered in depression. The observation of the effect of antidepressants on monoaminergic transmitters leads to the hypothesis of monoamines. However this hypothesis cannot explain many of the mechanisms involved in the action of antidepressants. The new hypothesis proposed to explain the action of antidepressant is the neuro-plasticity hypothesis. This hypothesis suggests that the effects of antidepressants on nervous, immune and endocrine systems are able to induce neuroadaptative changes in the brain. The neuroplasticity have been described as the ability of the brain to reorganize itself and form new neuronal connections throughout life. It is proposed that antidepressants influence neuroplasticity inducing improvements in the symptoms of this illness.

Plasmon resonance enhancement of nonlinear properties of amino acids

NASA Astrophysics Data System (ADS)

de Araujo, Renato E.; Rativa, Diego; Gomes, Anderson S. L.

2007-02-01

Here we analyze the influence of 9 nm (mean diameter) silver particles on the nonlinear properties of intrinsic cell molecules. A novel high sensitivity thermal managed eclipse Z-scan technique with a femtosecond laser system was used to analyze the nonlinear susceptibility of water solution of fluorescent and non-fluorescent amino acids (Tryptophan, Tyrosine, Phenylalanine, Proline and Histidine) with different concentration of silver nanoparticles. The generalized Maxwell Garnett model is used to explain the behavior of the measured nonlinear refractive index with the change of the nanoparticles concentration in the sample.

Nonlinear effects of electromagnetic forces on primary resonance of a levitated elastic bar supported by high- Tc superconducting bearings

NASA Astrophysics Data System (ADS)

Iori, T.; Ogawa, S.; Sugiura, T.

2007-10-01

This research investigates nonlinear dynamics of an elastic body supported at both its ends by electromagnetic forces between superconductors and magnets. We focus on the primary resonance of each eigenmode under vertical excitation of superconducting bulks. Experiment and numerical analysis show the softening tendency in the resonance of the 3rd mode consisting of mainly deflection and slightly translation. This nonlinear response can be theoretically explained only by nonlinear coupling between the 1st and 3rd modes through their quadratic terms.

Depressive status explains a significant amount of the variance in COPD assessment test (CAT) scores

PubMed Central

Miravitlles, Marc; Molina, Jesús; Quintano, José Antonio; Campuzano, Anna; Pérez, Joselín; Roncero, Carlos

2018-01-01

Background COPD assessment test (CAT) is a short, easy-to-complete health status tool that has been incorporated into the multidimensional assessment of COPD in order to guide therapy; therefore, it is important to understand the factors determining CAT scores. Methods This is a post hoc analysis of a cross-sectional, observational study conducted in respiratory medicine departments and primary care centers in Spain with the aim of identifying the factors determining CAT scores, focusing particularly on the cognitive status measured by the Mini-Mental State Examination (MMSE) and levels of depression measured by the short Beck Depression Inventory (BDI). Results A total of 684 COPD patients were analyzed; 84.1% were men, the mean age of patients was 68.7 years, and the mean forced expiratory volume in 1 second (%) was 55.1%. Mean CAT score was 21.8. CAT scores correlated with the MMSE score (Pearson’s coefficient r=−0.371) and the BDI (r=0.620), both p<0.001. In the multivariate analysis, the usual COPD severity variables (age, dyspnea, lung function, and comorbidity) together with MMSE and BDI scores were significantly associated with CAT scores and explained 45% of the variability. However, a model including only MMSE and BDI scores explained up to 40% and BDI alone explained 38% of the CAT variance. Conclusion CAT scores are associated with clinical variables of severity of COPD. However, cognitive status and, in particular, the level of depression explain a larger percentage of the variance in the CAT scores than the usual COPD clinical severity variables. PMID:29563782

Depressive status explains a significant amount of the variance in COPD assessment test (CAT) scores.

PubMed

Miravitlles, Marc; Molina, Jesús; Quintano, José Antonio; Campuzano, Anna; Pérez, Joselín; Roncero, Carlos

2018-01-01

COPD assessment test (CAT) is a short, easy-to-complete health status tool that has been incorporated into the multidimensional assessment of COPD in order to guide therapy; therefore, it is important to understand the factors determining CAT scores. This is a post hoc analysis of a cross-sectional, observational study conducted in respiratory medicine departments and primary care centers in Spain with the aim of identifying the factors determining CAT scores, focusing particularly on the cognitive status measured by the Mini-Mental State Examination (MMSE) and levels of depression measured by the short Beck Depression Inventory (BDI). A total of 684 COPD patients were analyzed; 84.1% were men, the mean age of patients was 68.7 years, and the mean forced expiratory volume in 1 second (%) was 55.1%. Mean CAT score was 21.8. CAT scores correlated with the MMSE score (Pearson's coefficient r =-0.371) and the BDI ( r =0.620), both p <0.001. In the multivariate analysis, the usual COPD severity variables (age, dyspnea, lung function, and comorbidity) together with MMSE and BDI scores were significantly associated with CAT scores and explained 45% of the variability. However, a model including only MMSE and BDI scores explained up to 40% and BDI alone explained 38% of the CAT variance. CAT scores are associated with clinical variables of severity of COPD. However, cognitive status and, in particular, the level of depression explain a larger percentage of the variance in the CAT scores than the usual COPD clinical severity variables.

Burden and Cognitive Appraisal of Stroke Survivors' Informal Caregivers: An Assessment of Depression Model With Mediating and Moderating Effects.

PubMed

Tsai, Yi-Chen; Pai, Hsiang-Chu

2016-04-01

This study proposes and evaluates a model of depression that concerns the role of burden and cognitive appraisal as mediators or moderators of outcomes among stroke survivor caregivers. A total of 105 informal caregivers of stroke survivor completed the self-report measures of Caregiver Burden Inventory, Center for Epidemiologic Studies Depression Scale, and Cognitive Impact of Appraisal Scale. The Glasgow Coma Scale and Barthel Index were used by the researcher to examine the physical functional status of the survivor. Partial least squares (PLS) path modeling was used to estimate the parameters of a depression model that included mediating or moderating effects. The model shows that burden and impact of cognitive appraisal have a significant direct and indirect impact on depression, while survivor physical functional status does not have a direct impact. The model also demonstrates that burden and impact of cognitive appraisal separately play a mediating role between survivor physical functional status and caregiver depression. In addition, cognitive appraisal has a moderating influence on the relationship between burden and depression. Overall, survivor physical functional status, burden, and cognitive appraisal were the predictors of caregiver depression, explaining 47.1% of the variance. This study has shown that burden and cognitive appraisal are mediators that more fully explain the relationship between patient severity and caregiver depression. Copyright © 2015 Elsevier Inc. All rights reserved.

Effects of long-term AA attendance and spirituality on the course of depressive symptoms in individuals with alcohol use disorder.

PubMed

Wilcox, Claire E; Pearson, Matthew R; Tonigan, J Scott

2015-06-01

Alcohol use disorder (AUD) is associated with depression. Although attendance at Alcoholics Anonymous (AA) meetings predicts reductions in drinking, results have been mixed about the salutary effects of AA on reducing depressive symptoms. In this single-group study, early AA affiliates (n = 253) were recruited, consented, and assessed at baseline, 3, 6, 9, 12, 18, and 24 months. Lagged growth models were used to investigate the predictive effect of AA attendance on depression, controlling for concurrent drinking and treatment attendance. Depression was measured using the Beck Depression Inventory (BDI) and was administered at baseline 3, 6, 12, 18, and 24 months. Additional predictors of depression tested included spiritual gains (Religious Background and Behavior questionnaire [RBB]) and completion of 12-step work (Alcoholics Anonymous Inventory [AAI]). Eighty-five percent of the original sample provided follow-up data at 24 months. Overall, depression decreased over the 24 month follow-up period. AA attendance predicted later reductions in depression (slope = -3.40, p = .01) even after controlling for concurrent drinking and formal treatment attendance. Finally, increased spiritual gains (RBB) also predicted later reductions in depression (slope = -0.10, p = .02) after controlling for concurrent drinking, treatment, and AA attendance. In summary, reductions in alcohol consumption partially explained decreases in depression in this sample of early AA affiliates, and other factors such as AA attendance and increased spiritual practices also accounted for reductions in depression beyond that explained by drinking. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

Country- and individual-level socioeconomic determinants of depression: multilevel cross-national comparison.

PubMed

Rai, Dheeraj; Zitko, Pedro; Jones, Kelvyn; Lynch, John; Araya, Ricardo

2013-03-01

The prevalence and correlates of depression vary across countries. Contextual factors such as country-level income or income inequalities have been hypothesised to contribute to these differences. To investigate associations of depression with socioeconomic factors at the country level (income inequality, gross national income) and individual (education, employment, assets and spending) level, and to investigate their relative contribution in explaining the cross-national variation in the prevalence of depression. Multilevel study using interview data of 187 496 individuals from 53 countries participating in the World Health Organization World Health Surveys. Depression prevalence varied between 0.4 and 15.7% across countries. Individual-level factors were responsible for 86.5% of this variance but there was also reasonable variation at the country level (13.5%), which appeared to increase with decreasing economic development of countries. Gross national income or country-level income inequality had no association with depression. At the individual level, fewer material assets, lower education, female gender, economic inactivity and being divorced or widowed were associated with increased odds of depression. Greater household spending, unlike material assets, was associated with increasing odds of depression (adjusted analysis). The variance of depression prevalence attributable to country-level factors seemed to increase with decreasing economic development of countries. However, country-level income inequality or gross national income explained little of this variation, and individual-level factors appeared more important than contextual factors as determinants of depression. The divergent relationship of assets and spending with depression emphasise that different socioeconomic measures are not interchangeable in their associations with depression.

The periodic structure of the natural record, and nonlinear dynamics.

USGS Publications Warehouse

Shaw, H.R.

1987-01-01

This paper addresses how nonlinear dynamics can contribute to interpretations of the geologic record and evolutionary processes. Background is given to explain why nonlinear concepts are important. A resume of personal research is offered to illustrate why I think nonlinear processes fit with observations on geological and cosmological time series data. The fabric of universal periodicity arrays generated by nonlinear processes is illustrated by means of a simple computer mode. I conclude with implications concerning patterns of evolution, stratigraphic boundary events, and close correlations of major geologically instantaneous events (such as impacts or massive volcanic episodes) with any sharply defined boundary in the geologic column. - from Author

Why is past depression the best predictor of future depression? Stress generation as a mechanism of depression continuity in girls.

PubMed

Rudolph, Karen D; Flynn, Megan; Abaied, Jamie L; Groot, Alison; Thompson, Renee

2009-07-01

This study examined whether a transactional interpersonal life stress model helps to explain the continuity in depression over time in girls. Youth (86 girls, 81 boys; M age = 12.41, SD = 1.19) and their caregivers participated in a three-wave longitudinal study. Depression and episodic life stress were assessed with semistructured interviews. Path analysis provided support for a transactional interpersonal life stress model in girls but not in boys, wherein depression predicted the generation of interpersonal stress, which predicted subsequent depression. Moreover, self-generated interpersonal stress partially accounted for the continuity of depression over time. Although depression predicted noninterpersonal stress generation in girls (but not in boys), noninterpersonal stress did not predict subsequent depression.

Sexual orientation and alcohol problem use among U.K. adolescents: an indirect link through depressed mood.

PubMed

Pesola, Francesca; Shelton, Katherine H; van den Bree, Marianne B M

2014-07-01

Sexual minority adolescents are more likely to engage in alcohol use than their heterosexual counterparts; however, the underlying reasons remain unclear and longitudinal research is limited. Owing to evidence that this group also experiences greater depressive symptoms than their peers, we aimed to (i) assess to what extent depressed mood explains the increased likelihood of engaging in alcohol use among sexual minority adolescents, and (ii) explore potential gender-specific patterns. Structural equation modelling was used to test the indirect relationship between sexual orientation and alcohol use through depressed mood, with heterosexuals as the reference group. A total of 3710 adolescents (12% sexual minority), from the Avon Longitudinal Study of Parents and Children (ALSPAC) study, assessed between the ages of 15 and 18 years. Sexual orientation was assessed at age 15, while alcohol use was measured using the Alcohol Use Disorders Identification Test (AUDIT) at age 18. Depressed mood was indexed by the Short Mood and Feelings Questionnaire (SMFQ) at age 16. Sexual minority adolescents were more likely to engage in alcohol problem use compared to their heterosexual counterparts [Btotal  = 0.12, 95% confidence interval (CI) = 0.04-0.20, P = 0.003]. Depressed mood explained 21% of the link between sexual orientation and alcohol use after adjustment for covariates and earlier measures (Z = 3.2, P = 0.001). No gender differences were observed. A higher prevalence of alcohol problem use in adolescents who are gay, lesbian or bisexual is partly explained by increased rates of depression in this group. © 2014 Society for the Study of Addiction.

Social Factors Explaining Children's Subjective Happiness and Depressive Symptoms

ERIC Educational Resources Information Center

Uusitalo-Malmivaara, Lotta; Lehto, Juhani E.

2013-01-01

In this study happiness and depression in 737 12-year-old Finnish children were predicted by relationships with family members and other people, the number of close friends and their experiences of parental fighting and drinking. There were no differences in happiness between the genders, but the girls were more depressed than the boys. Low…

Influences and Mediators of the Effect of Poverty on Young Adolescent Depressive Symptoms.

ERIC Educational Resources Information Center

Eamon, Mary Keegan

2002-01-01

Analyzed data from the mother-child data set of the National Longitudinal Survey of Youth for 898 young adolescents (10-12 years) to study the influences that explain the relations between poverty and depressive symptoms measured 2 years later. Findings show that youth depressive symptoms are multiply determined, and that poverty can adversely…

Heritability of Anxious-Depressive and Withdrawn Behavior: Age-Related Changes during Adolescence

ERIC Educational Resources Information Center

Lamb, Diane J.; Middeldorp, Christel M.; van Beijsterveldt, Catarina E. M.; Bartels, Meike; van der Aa, Niels; Polderman, Tinca J. C.; Boomsma, Dorret I.

2010-01-01

Objective: To explain the differential course of anxiety and depression in individuals from childhood to adulthood by examining age-related changes in the genetic and environmental etiology of anxious and depressive symptoms. Method: A sample of 1470, 1839, and 2023 Dutch twins aged 12, 14, and 16 years reported on symptoms of anxious depression…

Testing a Gender Additive Model: The Role of Body Image in Adolescent Depression

ERIC Educational Resources Information Center

Bearman, Sarah Kate; Stice, Eric

2008-01-01

Despite consistent evidence that adolescent girls are at greater risk of developing depression than adolescent boys, risk factor models that account for this difference have been elusive. The objective of this research was to examine risk factors proposed by the "gender additive" model of depression that attempts to partially explain the increased…

Does Powerlessness Explain the Relationship between Intimate Partner Violence and Depression?

ERIC Educational Resources Information Center

Filson, Jennifer; Ulloa, Emilio; Runfola, Cristin; Hokoda, Audrey

2010-01-01

The current study aimed to test whether relationship power could act as a mediator of the relationship between intimate partner violence and depression. The proposed mediation model was based on the theory of gender and power and on previous research of intimate partner violence and depression. Survey results from a sample of 327 single…

Alone? Perceived social support and chronic interpersonal difficulties in suicidal elders.

PubMed

Harrison, Katrin E; Dombrovski, Alexandre Y; Morse, Jennifer Q; Houck, Patricia; Schlernitzauer, Maryann; Reynolds, Charles F; Szanto, Katalin

2010-05-01

Social networks may protect depressed elders against suicidal behavior. However, conflict in important relationships may undermine the sense of social support, potentially negating the protective effects. Thus, we investigated the role of chronic interpersonal difficulties and perceived social support in depressed elders with and without suicidal thoughts and attempts. 106 individuals aged 60 years and older participated in this cross-sectional, case-control study. They were placed in three groups: suicidal depressed, non-suicidal depressed and non-depressed. Following a detailed clinical characterization, we assessed perceived social support (Interpersonal Support Evaluation List), and chronic interpersonal difficulties (Inventory of Interpersonal Problems). Using general linear models, we explored the relationship between suicidal thoughts/attempts, social support, and chronic interpersonal difficulties. We also examined whether lower perceived social support explained the relationship between chronic interpersonal difficulties and suicidal thoughts/attempts. Suicidal depressed elders reported the lowest levels of perceived social support (belonging, tangible support, and self-esteem) and higher levels of chronic interpersonal difficulties (struggle against others and interpersonal hostility), compared to both non-suicidal depressed and non-depressed elders. The relationship between chronic interpersonal difficulties and suicidal behavior was partially explained by low perceived social support. The experience of strong affects, interpersonal struggle, and hostility in relationships may undermine the sense of social support in depressed elders, possibly leading them to contemplate or attempt suicide. Depressed elders with a history of interpersonal difficulties need to be carefully monitored for suicidal behavior.

Optimism, well-being, depressive symptoms, and perceived physical health: a study among Stroke survivors.

PubMed

Shifren, Kim; Anzaldi, Kristen

2018-01-01

The investigation of the relation of positive personality characteristics to mental and physical health among Stroke survivors has been a neglected area of research. The purpose of this study was to examine the relationship between optimism, well-being, depressive symptoms, and perceived physical health among Stroke survivors. It was hypothesized that Stroke survivors' optimism would explain variance in their physical health above and beyond the variance explained by demographic variables, diagnostic variables, and mental health. One hundred seventy-six Stroke survivors (97 females, 79 males) completed the Revised Life Orientation Test, the Center for Epidemiological Studies Depression Scale, two items on perceived physical health from the 36-item Short Form of the Medical Outcomes study, and the Identity scale of the Illness Perception Questionnaire. Pearson correlations, hierarchical regression analyses, and the PROCESS approach to determining mediators were used to assess hypothesized relations between variables. Stroke survivors' level of optimism explained additional variance in overall health in regression models controlling for demographic and diagnostic variables, and mental health. Analyses revealed that optimism played a partial mediator role between mental health (well-being, depressive symptoms and total score on CES-D) variables and overall health.

Coulomb Blockade in a Two-Dimensional Conductive Polymer Monolayer.

PubMed

Akai-Kasaya, M; Okuaki, Y; Nagano, S; Mitani, T; Kuwahara, Y

2015-11-06

Electronic transport was investigated in poly(3-hexylthiophene-2,5-diyl) monolayers. At low temperatures, nonlinear behavior was observed in the current-voltage characteristics, and a nonzero threshold voltage appeared that increased with decreasing temperature. The current-voltage characteristics could be best fitted using a power law. These results suggest that the nonlinear conductivity can be explained using a Coulomb blockade (CB) mechanism. A model is proposed in which an isotropic extended charge state exists, as predicted by quantum calculations, and percolative charge transport occurs within an array of small conductive islands. Using quantitatively evaluated capacitance values for the islands, this model was found to be capable of explaining the observed experimental data. It is, therefore, suggested that percolative charge transport based on the CB effect is a significant factor giving rise to nonlinear conductivity in organic materials.

Spreading of healthy mood in adolescent social networks

PubMed Central

Hill, E. M.; Griffiths, F. E.; House, T.

2015-01-01

Depression is a major public health concern worldwide. There is evidence that social support and befriending influence mental health, and an improved understanding of the social processes that drive depression has the potential to bring significant public health benefits. We investigate transmission of mood on a social network of adolescents, allowing flexibility in our model by making no prior assumption as to whether it is low mood or healthy mood that spreads. Here, we show that while depression does not spread, healthy mood among friends is associated with significantly reduced risk of developing and increased chance of recovering from depression. We found that this spreading of healthy mood can be captured using a non-linear complex contagion model. Having sufficient friends with healthy mood can halve the probability of developing, or double the probability of recovering from, depression over a 6–12-month period on an adolescent social network. Our results suggest that promotion of friendship between adolescents can reduce both incidence and prevalence of depression. PMID:26290075

Spreading of healthy mood in adolescent social networks.

PubMed

Hill, E M; Griffiths, F E; House, T

2015-08-22

Depression is a major public health concern worldwide. There is evidence that social support and befriending influence mental health, and an improved understanding of the social processes that drive depression has the potential to bring significant public health benefits. We investigate transmission of mood on a social network of adolescents, allowing flexibility in our model by making no prior assumption as to whether it is low mood or healthy mood that spreads. Here, we show that while depression does not spread, healthy mood among friends is associated with significantly reduced risk of developing and increased chance of recovering from depression. We found that this spreading of healthy mood can be captured using a non-linear complex contagion model. Having sufficient friends with healthy mood can halve the probability of developing, or double the probability of recovering from, depression over a 6-12-month period on an adolescent social network. Our results suggest that promotion of friendship between adolescents can reduce both incidence and prevalence of depression. © 2015 The Authors.

Determinants of access to health care for depression in 49 countries: A multilevel analysis.

PubMed

Araya, Ricardo; Zitko, Pedro; Markkula, Niina; Rai, Dheeraj; Jones, Kelvyn

2018-07-01

The relative importance of individual and country-level factors influencing access to diagnosis and treatment for depression across the world is fairly unknown. We analysed cross-national data from the WHO World Health Surveys. Depression diagnosis and access to health care were ascertained using a structured interview. Logistic Bayesian Multilevel analyses were performed to establish individual and country level factors associated with: (1) receiving a diagnosis and (2) accessing treatment for depression if a diagnosis was ascertained. The sample included 7870 individuals from 49 countries who met ICD-10 criteria for depressive episode in the past 12 months. A third (32%) of these individuals had ever been diagnosed with depression in their lifetime. Among those diagnosed with depression, 66% reported to have ever received treatment for depression. Although individual factors were more important determinants of access to treatment for depression, country-level factors explained 27.6% of the variance in access to diagnosis and 24.1% in access to treatment. Access to treatment for depression improved with increasing country income. Female gender, better education, the presence of physical co-morbidity, more material assets, and living in urban areas were individual level determinants of better access. Data on other contextual factors was not available. Unmet need was likely underestimated, since only lifetime treatment data was available. This study highlights major inequalities in access to a diagnosis and treatment of depression. Unlike the prevalence of depression, where contextual factors have shown to have less importance, a significant proportion of the variance in access to depression care was explained by country-level income. Copyright © 2018 Elsevier B.V. All rights reserved.

Internet Gaming Disorder Explains Unique Variance in Psychological Distress and Disability After Controlling for Comorbid Depression, OCD, ADHD, and Anxiety.

PubMed

Pearcy, Benjamin T D; McEvoy, Peter M; Roberts, Lynne D

2017-02-01

This study extends knowledge about the relationship of Internet Gaming Disorder (IGD) to other established mental disorders by exploring comorbidities with anxiety, depression, Attention Deficit Hyperactivity Disorder (ADHD), and obsessive compulsive disorder (OCD), and assessing whether IGD accounts for unique variance in distress and disability. An online survey was completed by a convenience sample that engages in Internet gaming (N = 404). Participants meeting criteria for IGD based on the Personal Internet Gaming Disorder Evaluation-9 (PIE-9) reported higher comorbidity with depression, OCD, ADHD, and anxiety compared with those who did not meet the IGD criteria. IGD explained a small proportion of unique variance in distress (1%) and disability (3%). IGD accounted for a larger proportion of unique variance in disability than anxiety and ADHD, and a similar proportion to depression. Replications with clinical samples using longitudinal designs and structured diagnostic interviews are required.

Neglected children, shame-proneness, and depressive symptoms.

PubMed

Bennett, David S; Sullivan, Margaret Wolan; Lewis, Michael

2010-11-01

Neglected children may be at increased risk for depressive symptoms. This study examines shame-proneness as an outcome of child neglect and as a potential explanatory variable in the relation between neglect and depressive symptoms. Participants were 111 children (52 with a Child Protective Services [CPS] allegation of neglect) seen at age 7. Neglected children reported more shame-proneness and more depressive symptoms than comparison children. Guilt-proneness, in contrast, was unrelated to neglect and depressive symptoms, indicating specificity for shame-proneness. The potential role of shame as a process variable that can help explain how some neglected children exhibit depressive symptoms is discussed.

Impact of oppositional defiant disorder dimensions on the temporal ordering of conduct problems and depression across childhood and adolescence in girls.

PubMed

Hipwell, Alison E; Stepp, Stephanie; Feng, Xin; Burke, Jeff; Battista, Deena R; Loeber, Rolf; Keenan, Kate

2011-10-01

Little is known about the role of oppositional defiant disorder (ODD) dimensions on the temporal unfolding of conduct disorder (CD) and depression in girls between childhood and adolescence. The year-to-year associations between CD and depressive symptomatology were examined using nine waves of annually collected data (ages 8 through 16 years) from 1215 participants of the Pittsburgh Girls Study. A series of autoregressive path models were tested that included ODD-Emotion Dysregulation (ODD-ED) and ODD-Defiance, as time-varying covariates on CD predicting depression severity in the following year, and vice versa. Conduct problems, depression, and ODD dimensions were relatively stable throughout childhood and adolescence, and a moderate degree of covariance was observed between these variables. Path analyses showed that CD often preceded depression across this developmental period, although the effect sizes were small. There was less consistent prediction from depression to CD. The overlap between ODD-ED and CD partially explained the prospective relations from CD to depression, whereas these paths were fully explained by the overlap between ODD-ED and depression. The overlap between ODD-Defiance and CD did not account for the prospective relations from CD to depression. In contrast, the overlap between ODD-Defiance and depression accounted for virtually all paths from CD to depression. Accounting for the overlap between ODD dimensions and both CD and depression eliminated all significant predictive paths. Symptoms of CD tend to precede depression in girls during childhood and adolescence. However, covariance between depression and both ODD-ED and ODD-Defiance accounts for these prospective relations. ODD dimensions should be assessed when evaluating risk for comorbid depression in girls with conduct problems, and emotion dysregulation and defiance aspects of ODD should be identified as targets for treatment in order to prevent depression in the future. © 2011 The Authors. Journal of Child Psychology and Psychiatry © 2011 Association for Child and Adolescent Mental Health.

Paternal depression in the postnatal period and child development: mediators and moderators.

PubMed

Gutierrez-Galve, Leticia; Stein, Alan; Hanington, Lucy; Heron, Jon; Ramchandani, Paul

2015-02-01

To explore potential mediating and moderating factors that influence the association between paternal depression in the postnatal period and subsequent child behavioral and emotional problems. A population-based cohort (N = 13,822) from the Avon Longitudinal Study of Parents and Children (ALSPAC) was recruited during pregnancy. Paternal and maternal depressive symptoms were assessed with the Edinburgh Postnatal Depression Scale at 8 weeks after the birth of the child. Child outcomes were assessed at 3.5 years by using the Rutter revised preschool scales and at 7 years by using the Strengths and Difficulties Questionnaire. Path analysis was used to assess hypothesized mediators (ie, depression in the other parent, couple conflict, and paternal noninvolvement) of the associations between both paternal and maternal depression and child outcomes. We also tested for hypothesized moderators (ie, paternal education and antisocial traits). Family factors (maternal depression and couple conflict) mediated two-thirds of the overall association between paternal depression and child outcomes at 3.5 years. Similar findings were seen when children were 7 years old. In contrast, family factors mediated less than one-quarter of the association between maternal depression and child outcomes. There was no evidence of moderating effects of either parental education or antisocial traits. The majority of the association between depression in fathers postnatally and subsequent child behavior is explained by the mediating role of family environment, whereas the association between depression in mothers and child outcomes appears to be better explained by other factors, perhaps including direct mother-infant interaction. Copyright © 2015 by the American Academy of Pediatrics.

Stigma and Postpartum Depression Treatment Acceptability Among Black and White Women in the First Six-Months Postpartum.

PubMed

Bodnar-Deren, Susan; Benn, E K T; Balbierz, Amy; Howell, E A

2017-07-01

Objective To measure stigma associated with four types of postpartum depression therapies and to estimate the association between stigma and the acceptance of these therapies for black and white postpartum mothers. Methods Using data from two postpartum depression randomized trials, this study included 481 black and white women who gave birth in a large urban hospital and answered a series of questions at 6-months postpartum. Survey items included socio demographic and clinical factors, attitudes about postpartum depression therapies and stigma. The associations between race, stigma, and treatment acceptability were examined using bivariate and multivariate analyses. Results Black postpartum mothers were less likely than whites to accept prescription medication (64 vs. 81%, p = 0.0001) and mental health counseling (87 vs. 93%, p = 0.001) and more likely to accept spiritual counseling (70 vs. 52%, p = 0.0002). Women who endorsed stigma about receipt of postpartum depression therapies versus those who did not were less likely to accept prescription medication, mental health and spiritual counseling for postpartum depression. Overall black mothers were less likely to report stigma associated with postpartum depression therapies. In adjusted models, black women versus white women remained less likely to accept prescription medication for postpartum depression (OR = 0.42, 95% CI 0.24-0.72) and stigma did not explain this difference. Conclusions Although treatment stigma is associated with lower postpartum depression treatment acceptance, stigma does not explain the lower levels of postpartum depression treatment acceptance among black women. More research is needed to understand treatment barriers for postpartum depression, especially among black women.

Depressed mood in breast cancer survivors: associations with physical activity, cancer-related fatigue, quality of life, and fitness level.

PubMed

Galiano-Castillo, Noelia; Ariza-García, Angelica; Cantarero-Villanueva, Irene; Fernández-Lao, Carolina; Díaz-Rodríguez, Lourdes; Arroyo-Morales, Manuel

2014-04-01

One out of five cancer survivors suffer from depression after oncology treatment. The aim of this study was to examine the relationship between depression and quality of life (QoL), cancer-related symptoms, physical activity level, health-related fitness, and salivary flow rate in breast cancer survivors. 108 breast cancer survivors in the year after the conclusion of treatment were included in this cross-sectional study. Demographic and clinically relevant information, cancer-related fatigue (Piper Fatigue Scale), QoL (QLQ-Br23 module), pain intensity VAS scale, salivary flow rate, physical activity level (Minnesota Leisure Time Physical Activity Questionnaire), and health-related fitness were assessed in all participants. Depressed mood was measured with the Profile of Mood States (POMS) Depression subscale. Significant positive correlations between depressed mood and fatigue, systemic side effects, perceived shoulder pain, and breast-arms symptoms (r ranged between .57 and .28, P < .01) were found. In addition, significant negative correlations between depressed mood and body image, future perspective, force handgrip, and physical activity level (r ranged between -.41 and -.19; p < .05) were found. Regression analyses revealed that cancer-related fatigue, physical activity level, systemic side effects, and body image were significant predictors of depressed mood, and when combined, they explained 39.6% of the variance in depressed mood. Cancer-related fatigue, physical activity level, and QoL partially explain the variability of depressed mood in breast cancer survivors. This paper facilitates a better understanding of the relationship between depressed mood and possible factors associated with it. Copyright © 2013 Elsevier Ltd. All rights reserved.

Explaining the relation between pathological gambling and depression: Rumination as an underlying common cause.

PubMed

Krause, Kristian; Bischof, Anja; Lewin, Silvia; Guertler, Diana; Rumpf, Hans-Jürgen; John, Ulrich; Meyer, Christian

2018-05-30

Background and aims Symptoms of pathological gambling (SPG) and depression often co-occur. The nature of this relationship remains unclear. Rumination, which is well known to be associated with depression, might act as a common underlying factor explaining the frequent co-occurrence of both conditions. The aim of this study is to analyze associations between the rumination subfactors brooding and reflection and SPG. Methods Participants aged 14-64 years were recruited within an epidemiological study on pathological gambling in Germany. Cross-sectional data of 506 (80.4% male) individuals with a history of gambling problems were analyzed. The assessment included a standardized clinical interview. To examine the effects of rumination across different levels of problem gambling severity, sequential quantile regression was used to analyze the association between the rumination subfactors and SPG. Results Brooding (p = .005) was positively associated with the severity of problem gambling after adjusting for reflection, depressive symptoms, and sociodemographic variables. Along the distribution of problem gambling severity, findings hold for all but the lowest severity level. Reflection (p = .347) was not associated with the severity of problem gambling at the median. Along the distribution of problem gambling severity, there was an inverse association at only one quantile. Discussion and conclusions Brooding might be important in the development and maintenance of problem gambling. With its relations to depression and problem gambling, it might be crucial when it comes to explaining the high comorbidity rates between SPG and depression. The role of reflection in SPG remains inconclusive.

The implications of reduced metabolic rate in resource-limited corals.

PubMed

Jacobson, Lianne M; Edmunds, Peter J; Muller, Erik B; Nisbet, Roger M

2016-03-01

Many organisms exhibit depressed metabolism when resources are limited, a change that makes it possible to balance an energy budget. For symbiotic reef corals, daily cycles of light and periods of intense cloud cover can be chronic causes of food limitation through reduced photosynthesis. Furthermore, coral bleaching is common in present-day reefs, creating a context in which metabolic depression could have beneficial value to corals. In the present study, corals (massive Porites spp.) were exposed to an extreme case of resource limitation by starving them of food and light for 20 days. When resources were limited, the corals depressed area-normalized respiration to 37% of initial rates, and coral biomass declined to 64% of initial amounts, yet the corals continued to produce skeletal mass. However, the declines in biomass cannot account for the declines in area-normalized respiration, as mass-specific respiration declined to 30% of the first recorded time point. Thus, these corals appear to be capable of metabolic depression. It is possible that some coral species are better able to depress metabolic rates than others; such variation could explain differential survival during conditions that limit resources (e.g. shading). Furthermore, we found that maintenance of existing biomass, in part, supports the production of skeletal mass. This association could be explained if maintenance supplies needed energy (e.g. ATP) or inorganic carbon (i.e. CO2) that otherwise limits the production of skeletal mass. Finally, the observed metabolic depression can be explained as a change in pool sizes, and does not require a change in metabolic rules. © 2016. Published by The Company of Biologists Ltd.

Dynamics of cochlear nonlinearity: Automatic gain control or instantaneous damping?

PubMed

Altoè, Alessandro; Charaziak, Karolina K; Shera, Christopher A

2017-12-01

Measurements of basilar-membrane (BM) motion show that the compressive nonlinearity of cochlear mechanical responses is not an instantaneous phenomenon. For this reason, the cochlear amplifier has been thought to incorporate an automatic gain control (AGC) mechanism characterized by a finite reaction time. This paper studies the effect of instantaneous nonlinear damping on the responses of oscillatory systems. The principal results are that (i) instantaneous nonlinear damping produces a noninstantaneous gain control that differs markedly from typical AGC strategies; (ii) the kinetics of compressive nonlinearity implied by the finite reaction time of an AGC system appear inconsistent with the nonlinear dynamics measured on the gerbil basilar membrane; and (iii) conversely, those nonlinear dynamics can be reproduced using an harmonic oscillator with instantaneous nonlinear damping. Furthermore, existing cochlear models that include instantaneous gain-control mechanisms capture the principal kinetics of BM nonlinearity. Thus, an AGC system with finite reaction time appears neither necessary nor sufficient to explain nonlinear gain control in the cochlea.

Mathematical nonlinear optics

NASA Astrophysics Data System (ADS)

McLaughlin, David W.

1995-08-01

The principal investigator, together with a post-doctoral fellows Tetsuji Ueda and Xiao Wang, several graduate students, and colleagues, has applied the modern mathematical theory of nonlinear waves to problems in nonlinear optics and to equations directly relevant to nonlinear optics. Projects included the interaction of laser light with nematic liquid crystals and chaotic, homoclinic, small dispersive, and random behavior of solutions of the nonlinear Schroedinger equation. In project 1, the extremely strong nonlinear response of a continuous wave laser beam in a nematic liquid crystal medium has produced striking undulation and filamentation of the laser beam which has been observed experimentally and explained theoretically. In project 2, qualitative properties of the nonlinear Schroedinger equation (which is the fundamental equation for nonlinear optics) have been identified and studied. These properties include optical shocking behavior in the limit of very small dispersion, chaotic and homoclinic behavior in discretizations of the partial differential equation, and random behavior.

Association between depressive symptoms and metabolic syndrome is not explained by antidepressant medication: results from the PPP-Botnia Study.

PubMed

Pyykkönen, Antti-Jussi; Räikkönen, Katri; Tuomi, Tiinamaija; Eriksson, Johan G; Groop, Leif; Isomaa, Bo

2012-05-01

To study whether the frequently reported association between depressive symptoms and the metabolic syndrome (MetS) and its individual components are secondary to the use of antidepressant medication and to established diabetes or cardiovascular diseases (CVD). A population-based, random sample of 4,967 women and men aged 18-75 years. MetS was defined according to the new, harmonized criteria. Glucose tolerance was assessed by oral glucose tolerance test (OGTT). CVD, depressive symptoms, and use of antidepressant medication were self-reported. The odds for having the MetS increased over 10%for each standard deviation increase in depressive symptoms. Users of antidepressant medication had more than 50% increased odds for having the MetS. Depressive symptoms were also associated with higher glucose response during the OGTT, higher serum triglyceride and lower HDL-cholesterol concentrations, and higher waist circumference, while use of antidepressant medication was associated with higher triglycerides, waist circumference, and systolic blood pressure. The associations of depressive symptoms were not secondary to use of antidepressant medication and were not explained by established diabetes or CVD. Depressive symptoms, the MetS, and the individual components of MetS are related. These associations are not driven by use of antidepressant medication, established diabetes, or CVD.

Depression in Intimate Partner Violence Victims in Slovenia: A Crippling Pattern of Factors Identified in Family Practice Attendees.

PubMed

Guček, Nena Kopčavar; Selič, Polona

2018-01-26

This multi-centre cross-sectional study explored associations between prevalence of depression and exposure to intimate partner violence (IPV) at any time in patients' adult life in 471 participants of a previous IPV study. In 2016, 174 interviews were performed, using the Short Form Domestic Violence Exposure Questionnaire, the Zung Scale and questions about behavioural patterns of exposure to IPV. Family doctors reviewed patients' medical charts for period from 2012 to 2016, using the Domestic Violence Exposure Medical Chart Check List, for conditions which persisted for at least three years. Depression was found to be associated with any exposure to IPV in adult life and was more likely to affect women. In multivariable logistic regression modelling, factors associated with self-rated depression were identified (p < 0.05). Exposure to emotional and physical violence was identified as a risk factor in the first model, explaining 23% of the variance. The second model explained 66% of the variance; past divorce, dysfunctional family relationships and a history of incapacity to work increased the likelihood of depression in patients. Family doctors should consider IPV exposure when detecting depression, since lifetime IPV exposure was found to be 40.4% and 36.9% of depressed revealed it.

Dehydroepiandrosterone Sulfate Level Varies Nonlinearly with Symptom Severity in Major Depressive Disorder

PubMed Central

Uh, Dasom; Jeong, Hyun-Ghang; Choi, Kwang-Yeon; Oh, So-Young; Lee, Suji; Kim, Seung-Hyun; Joe, Sook-Haeng

2017-01-01

Objective The pathophysiology of major depressive disorder (MDD) is still not well understood. Conflicting results for surrogate biomarkers in MDD have been reported, which might be a consequence of the heterogeneity of MDD patients. Therefore, we aim to investigate how the severity of depression and various symptom domains are related to the levels of dehydroepiandrosterone sulfate (DHEA-s) in MDD patients. Methods We recruited 117 subjects from a general practice. Depressive symptoms were assessed using the Beck Depression Inventory (BDI). Depressive symptoms were divided into three subdomains according to BDI items; somatic symptoms, guilt and failure, and mood and inhibition. Results In subjects with very-mild-to-moderate depression, the DHEA-s level increased as BDI score did. However, the DHEA-s levels in the subjects with severe depression were significantly lower than in subjects with moderate depression (p=0.003). DHEA-s level was correlated with the BDI subscore for guilt and failure in very-mild-to-moderate depression (r=0.365, p=0.006). Conclusion The DHEA-s level appears to be indicative of MDD severity with respect to depressive symptoms, especially regarding guilt and failure. Our findings suggest that the upregulation of DHEA-s may be a part of a compensatory process in very-mild-to-moderate depression, and the failure of this compensation mechanism may underlie the development of severe depression. PMID:28449564

Why is Past Depression the Best Predictor of Future Depression? Stress Generation as a Mechanism of Depression Continuity in Girls

PubMed Central

Rudolph, Karen D.; Flynn, Megan; Abaied, Jamie; Groot, Alison; Thompson, Renee

2009-01-01

This study examined whether a transactional interpersonal life stress model helps to explain the continuity in depression over time in girls. Youth (86 girls, 81 boys; M age = 12.41, SD = 1.19) and their caregivers participated in a three-wave longitudinal study. Depression and episodic life stress were assessed with semi-structured interviews. Path analysis provided support for a transactional interpersonal life stress model in girls but not in boys, wherein depression predicted the generation of interpersonal stress, which predicted subsequent depression. Moreover, self-generated interpersonal stress partially accounted for the continuity of depression over time. Although depression predicted noninterpersonal stress generation in girls (but not in boys), noninterpersonal stress did not predict subsequent depression. PMID:20183635

Relationship Quality Buffers Association Between Co-rumination and Depressive Symptoms Among First Year College Students.

PubMed

Guassi Moreira, João F; Miernicki, Michelle E; Telzer, Eva H

2016-03-01

Co-rumination, the tendency to dwell on negative events and feelings with a relationship partner, is an aspect of relationships that has been associated with socioemotional adjustment tradeoffs and is found to be associated with depressive symptoms. However, depending on the context in which it occurs, co-rumination is not necessarily associated with detriments to mental well-being. Differences in relationship quality within certain relationships may explain why co-rumination is not always associated with depressive symptoms. In the current study, we utilized self-report measures in an ethnically diverse sample (53.5 % non-White) of 307 first term college students (65 % female) in order to elucidate how co-rumination between roommates may be associated with depressive symptoms. We found that the association between co-rumination and depressive symptoms was moderated by relationship quality such that co-rumination in a high quality relationship was not associated with depressive symptoms whereas the opposite was true in low quality relationships. Moreover, we found moderated mediation, such that the variance in the association between co-rumination and depressive symptoms was explained via self-esteem, but only for those co-ruminating within a low quality relationship. These results suggest that relationship quality may impact the extent to which co-rumination is associated with depressive symptoms among first year college students.

Prediction of specific depressive symptom clusters in youth with epilepsy: The NDDI-E-Y versus Neuro-QOL SF.

PubMed

Kellermann, Tanja S; Mueller, Martina; Carter, Emma G; Brooks, Byron; Smith, Gigi; Kopp, Olivia J; Wagner, Janelle L

2017-08-01

Proper assessment and early identification of depressive symptoms are essential to initiate treatment and minimize the risk for poor outcomes in youth with epilepsy (YWE). The current study examined the predictive utility of the Neurological Disorders Depression Inventory-Epilepsy for Youth (NDDI-E-Y) and the Neuro-QOL Depression Short Form (Neuro-QOL SF) in explaining variance in overall depressive symptoms and specific symptom clusters on the gold standard Children's Depression Inventory-2 (CDI-2). Cross-sectional study examining 99 YWE (female 68, mean age 14.7 years) during a routine epilepsy visit, who completed self-report measures of depressive symptoms, including the NDDI-E-Y, CDI-2, and the Neuro-QOL SF. Caregivers completed a measure of seizure severity. All sociodemographic and medical information was evaluated through electronic medical record review. After accounting for seizure and demographic variables, the NDDI-E-Y accounted for 45% of the variance in the CDI-2 Total score and the CDI-2 Ineffectiveness subscale. Furthermore, the NDDI-E-Y predicted CDI-2 Total scores and subscales similarly, with the exception of explaining significantly more variance in the CDI-2 Ineffectiveness subscale compared to the Negative Mood subscale. The NDDI-E-Y explained greater variance compared to Neuro-QOL SF across the Total (48% vs. 37%) and all CDI-2 subscale scores; however, the NDDI-E-Y emerged as a stronger predictor of only CDI-2 Ineffectiveness. Both the NDDI-E-Y and Neuro-QOL SF accounted for the lowest amount of variance in CDI-2 Negative Mood. Sensitivity was poor for the Neuro-QOL SF in predicting high versus low CDI-2 scores. The NDDI-E-Y has strong psychometrics and can be easily integrated into routine epilepsy care for quick, brief screening of depressive symptoms in YWE. Wiley Periodicals, Inc. © 2017 International League Against Epilepsy.

Longitudinal Links between Impulsivity, Gambling Problems and Depressive Symptoms: A Transactional Model from Adolescence to Early Adulthood

ERIC Educational Resources Information Center

Dussault, Frederic; Brendgen, Mara; Vitaro, Frank; Wanner, Brigitte; Tremblay, Richard E.

2011-01-01

Background: Research shows high co-morbidity between gambling problems and depressive symptoms, but the directionality of this link is unclear. Moreover, the co-occurrence of gambling problems and depressive symptoms could be spurious and explained by common underlying risk factors such as impulsivity and socio-family risk. The goals of the…

Correlates of Depressed Mothers' Sensitivity toward Their Infants: The Role of Maternal, Child, and Contextual Characteristics

ERIC Educational Resources Information Center

van Doesum, Karin T. M.; Hosman, Clemens M. H.; Riksen-Walraven, J. Marianne; Hoefnagels, Cees

2007-01-01

Objective: To examine various maternal, child, and contextual characteristics, as well as the number of risk factors present, to distinguish which factors explain variance in the sensitivity of depressed mothers toward their infants. Method: Participants were depressed mothers (n = 84) with their infants ages 1 month up to 1 year. Mothers were…

Possibilities and limitations of rod-beam theories. [nonlinear distortion tensor and nonlinear stress tensors

NASA Technical Reports Server (NTRS)

Peterson, D.

1979-01-01

Rod-beam theories are founded on hypotheses such as Bernouilli's suggesting flat cross-sections under deformation. These assumptions, which make rod-beam theories possible, also limit the accuracy of their analysis. It is shown that from a certain order upward terms of geometrically nonlinear deformations contradict the rod-beam hypotheses. Consistent application of differential geometry calculus also reveals differences from existing rod theories of higher order. These differences are explained by simple examples.

Nonlinear Constitutive Modeling of Piezoelectric Ceramics

NASA Astrophysics Data System (ADS)

Xu, Jia; Li, Chao; Wang, Haibo; Zhu, Zhiwen

2017-12-01

Nonlinear constitutive modeling of piezoelectric ceramics is discussed in this paper. Van der Pol item is introduced to explain the simple hysteretic curve. Improved nonlinear difference items are used to interpret the hysteresis phenomena of piezoelectric ceramics. The fitting effect of the model on experimental data is proved by the partial least-square regression method. The results show that this method can describe the real curve well. The results of this paper are helpful to piezoelectric ceramics constitutive modeling.

The association between attention control, anxiety, and depression: the indirect effects of repetitive negative thinking and mood recovery.

PubMed

Kertz, Sarah J; Stevens, Kimberly T; Klein, Keith P

2017-07-01

Attention control deficits and repetitive negative thinking (RNT; i.e., rumination) may be key factors in the development and persistence of depression and anxiety, although their role in symptom development remains poorly understood. This represents a gap in the literature, as interventions targeting attention control and associated RNT may enhance interventions and prevent costly relapse. The current study was designed to examine the serial indirect effects of transdiagnostic RNT and negative affect recovery following a lab-induced stressor on the association between attention control deficits and trait anxiety and depression. Participants were N = 583 university students who completed validated measures of RNT, anxiety, depression, and mood ratings pre- and post-stressor. Stress was induced using a modified version of the Trier Social Stress Test. Results of cross-sectional indirect effects models indicated that RNT and mood recovery explained the association between attention control deficits and trait anxiety and depression. Results from reversed models indicated that only the indirect effect of RNT was significant. Findings suggest that RNT and mood recovery processes play an important role in explaining anxiety and depression symptoms. Additional work is needed to examine their role in symptom development and maintenance over time.

The Relations of Self-Reported Aggression to Alexithymia, Depression, and Anxiety After Traumatic Brain Injury.

PubMed

Neumann, Dawn; Malec, James F; Hammond, Flora M

To compare self-reported aggression in people with and without traumatic brain injury (TBI) and examine the relations of aggression to alexithymia (poor emotional insight), depression, and anxiety. Rehabilitation hospital. Forty-six adults with moderate to severe TBI who were at least 3 months postinjury; 49 healthy controls (HCs); groups were frequency matched for age and gender. Cross-sectional study using a quasi-experimental design. Aggression (Buss-Perry Aggression Questionnaire); alexithymia (Toronto Alexithymia Scale-20); depression (Patient Health Questionnaire-9); and trait anxiety (State-Trait Anxiety Inventory). Participants with TBI had significantly higher aggression scores than HCs. For participants with TBI, 34.2% of the adjusted variance of aggression was significantly explained by alexithymia, depression, and anxiety; alexithymia accounted for the largest unique portion of the variance in this model (16.2%). Alexithymia, depression, and anxiety explained 46% of the adjusted variance of aggression in HCs; in contrast to participants with TBI, depression was the largest unique contributor to aggression (15.9%). This was the first empirical study showing that poor emotional insight (alexithymia) significantly contributes to aggression after TBI. This relation, and the potential clinical implications it may have for the treatment of aggression, warrants further investigation.

Plasmon assisted enhanced nonlinear refraction of monodispersed silver nanoparticles and their tunability.

PubMed

Lama, Pemba; Suslov, Anatoliy; Walser, Ardie D; Dorsinville, Roger

2014-06-02

Nonlinear optical characterizations were performed on monodispersed silver (Ag) nanoparticles (NPs) of various sizes using a picosecond Z-scan technique with excitation wavelengths of 532 nm and 1064 nm. The Ag NPs were fabricated using a heterogeneous condensation technique in a gas medium. The nonlinear refraction values were higher for the monodispersed Ag NPs whose surface plasmon resonance (SPR) peak is closer to the excitation wavelength. The higher nonlinear optical response is explained in terms of an electric field enhancement near the SPR. Moreover, the fabrication method allows the tailoring of the nonlinear refraction index of the Ag NPs by tuning the SPR peak of the sample. A comparison of the nonlinear refraction index of the monodispersed and polydispersed Ag NPs showed that the nonlinear refractive index of the monodispersed Ag NPs is higher.

Enhanced nonlinear current-voltage behavior in Au nanoparticle dispersed CaCu 3 Ti 4 O 12 composite films

NASA Astrophysics Data System (ADS)

Chen, Cong; Wang, Can; Ning, Tingyin; Lu, Heng; Zhou, Yueliang; Ming, Hai; Wang, Pei; Zhang, Dongxiang; Yang, Guozhen

2011-10-01

An enhanced nonlinear current-voltage behavior has been observed in Au nanoparticle dispersed CaCu 3Ti 4O 12 composite films. The double Schottky barrier model is used to explain the enhanced nonlinearity in I-V curves. According to the energy-band model and fitting result, the nonlinearity in Au: CCTO film is mainly governed by thermionic emission in the reverse-biased Schottky barrier. This result not only supports the mechanism of double Schottky barrier in CCTO, but also indicates that the nonlinearity of current-voltage behavior could be improved in nanometal composite films, which has great significance for the resistance switching devices.

Social Contagion, Adolescent Sexual Behavior, and Pregnancy: A Nonlinear Dynamic EMOSA Model.

ERIC Educational Resources Information Center

Rodgers, Joseph Lee; Rowe, David C.; Buster, Maury

1998-01-01

Expands an existing nonlinear dynamic epidemic model of onset of social activities (EMOSA), motivated by social contagion theory, to quantify the likelihood of pregnancy for adolescent girls of different sexuality statuses. Compares five sexuality/pregnancy models to explain variance in national prevalence curves. Finds that adolescent girls have…

Linear and Non-Linear Thermal Lens Signal of the Fifth C-H Vibrational Overtone of Naphthalene in Liquid Solutions of Hexane

NASA Astrophysics Data System (ADS)

Manzanares, Carlos; Diaz, Marlon; Barton, Ann; Nyaupane, Parashu R.

2017-06-01

The thermal lens technique is applied to vibrational overtone spectroscopy of solutions of naphthalene in n-hexane. The pump and probe thermal lens technique is found to be very sensitive for detecting samples of low composition (ppm) in transparent solvents. In this experiment two different probe lasers: one at 488 nm and another 568 nm were used. The C-H fifth vibrational overtone spectrum of benzene is detected at room temperature for different concentrations. A plot of normalized integrated intensity as a function of concentration of naphthalene in solution reveals a non-linear behavior at low concentrations when using the 488 nm probe and a linear behavior over the entire range of concentrations when using the 568 nm probe. The non-linearity cannot be explained assuming solvent enhancement at low concentrations. A two color absorption model that includes the simultaneous absorption of the pump and probe lasers could explain the enhanced magnitude and the non-linear behavior of the thermal lens signal. Other possible mechanisms will also be discussed.

Superconducting nanowires as nonlinear inductive elements for qubits

NASA Astrophysics Data System (ADS)

Ku, Jaseung; Manucharyan, Vladimir; Bezryadin, Alexey

2010-10-01

We report microwave transmission measurements of superconducting Fabry-Perot resonators, having a superconducting nanowire placed at a supercurrent antinode. As the plasma oscillation is excited, the supercurrent is forced to flow through the nanowire. The microwave transmission of the resonator-nanowire device shows a nonlinear resonance behavior, significantly dependent on the amplitude of the supercurrent oscillation. We show that such amplitude-dependent response is due to the nonlinearity of the current-phase relationship of the nanowire. The results are explained within a nonlinear oscillator model of the Duffing oscillator, in which the nanowire acts as a purely inductive element, in the limit of low temperatures and low amplitudes. The low-quality factor sample exhibits a “crater” at the resonance peak at higher driving power, which is due to dissipation. We observe a hysteretic bifurcation behavior of the transmission response to frequency sweep in a sample with a higher quality factor. The Duffing model is used to explain the Duffing bistability diagram. We also propose a concept of a nanowire-based qubit that relies on the current dependence of the kinetic inductance of a superconducting nanowire.

Anxiety and depression in people with epilepsy: The contribution of metacognitive beliefs.

PubMed

Fisher, Peter L; Noble, Adam J

2017-08-01

Anxiety and depressive disorders frequently occur in people with epilepsy (PWE). An information processing model of psychopathology, the Self-Regulatory Executive Function (S-REF) model specifies that maladaptive metacognitive beliefs and processes play a fundamental role in the development and maintenance of anxiety and depression. This study explored whether metacognitive beliefs would explain additional variance in anxiety and depression after accounting for demographics, physical and/or psychiatric illnesses, epilepsy characteristics and medication issues. The mediational relationships between metacognitive beliefs, worry and anxiety and depression, predicted by the metacognitive model were also explored, METHODS: Three hundred and forty-nine PWE participated in an online survey and completed self-report questionnaires measuring anxiety, depression, metacognitive beliefs and worry. Participants also provided information on epilepsy characteristics, demographics, comorbid physical and/or psychiatric illnesses, number of, and perceived side effects of, anti-epileptic medication. Regression analysis showed that metacognitive beliefs were associated with symptoms of anxiety, depression, and explained additional variance in these outcomes after accounting for the control variables. Furthermore, the fundamental tenet of the metacognitive model was supported; the relationship between negative metacognitive beliefs about uncontrollability and danger of worry and anxious and depressive symptoms was partially mediated by worry. This is the first study to demonstrate that metacognitive beliefs and processes contribute to anxiety and depression beyond variables often associated with emotional distress in PWE. Further research is required to test if modification of metacognitive beliefs and processes using metacognitive therapy would effectively alleviate anxiety and depression in PWE. Copyright © 2017 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

Shame mediates the relationship between depression and addictive behaviours.

PubMed

Bilevicius, Elena; Single, Alanna; Bristow, Lindsay A; Foot, Melody; Ellery, Michael; Keough, Matthew T; Johnson, Edward A

2018-07-01

Alcohol and gambling problems are common in young adults. Self-medication theory states that young adults with depression drink and/or gamble to escape negative emotions. Research shows that depression is a risk factor for drinking/gambling problems, but more work is needed to examine mediators underlying these associations. One potential mediator is shame. Shame is a self-directed emotion that follows a negative life event and is characterized by intense feelings of inferiority, worthlessness, and embarrassment. Depressed individuals are especially susceptible to shame (and associated emotions). Shame has also been implicated in risk for addiction. Accordingly, we predicted that elevated shame would explain why depression is associated with both alcohol and gambling problems. A longitudinal design was used to examine this hypothesis. Undergraduates (N = 210) completed self-reports of depression at baseline (Time 1) and then completed self-reports of shame, alcohol misuse, gambling problems one month later (Time 2). Results showed that individuals with elevated depression at Time 1 endorsed high levels of shame at Time 2, which in turn predicted more gambling (β = .038, 95% CI [.010, .087]) and alcohol problems (β = .249, 95% CI [.123, .435]) at Time 2. We found that increased levels of shame explained the effects of depression on problem drinking and gambling. Study findings improve our understanding of the depressive pathway to addiction by providing evidence for shame as a potential mechanism of this pathway. Reducing shame can be a target of clinical interventions for young adults with depression and alcohol/gambling problems. Copyright © 2018 Elsevier Ltd. All rights reserved.

Cancer-related fatigue and depression in breast cancer patients postchemotherapy: Different associations with optimism and stress appraisals.

PubMed

Levkovich, Inbar; Cohen, Miri; Pollack, Shimon; Drumea, Karen; Fried, Georgeta

2015-10-01

Symptoms of depression and cancer-related fatigue (CRF) are common among breast cancer patients postchemotherapy and may seriously impair quality of life (QoL). This study aimed to assess the relationship between depression and CRF in breast cancer patients postchemotherapy and to examine their relationships to optimism and to threat and challenge appraisals. Participants included 95 breast cancer patients (stages 1-3) 1 to 6 months after completion of chemotherapy. Patients submitted personal and medical details and completed the following: physical symptom questionnaires (EORTC QLQ-C30, and QLQ-BR23), a symptoms of depression questionnaire (CES-D), the Fatigue Symptom Inventory (FSI), the Life Orientation Test (LOT-R), and a stress appraisals questionnaire. We found levels of depression, CRF, and appraisals of cancer as a threat to bemoderate and levels of optimism and appraisals of cancer as a challenge to be high. Depression and CRF were positively associated. A multivariate regression analysis revealed that 51% of the CRF variancewas explained; physical symptoms and threat appraisal were significantly associated with CRF. A 67% of the CRF variance of depression was explained; challenge and threat appraisals were significantly associated with depression [corrected]. Although CRF and depression were often experienced simultaneously and both were found to be higher among individuals who gave higher appraisals of cancer as a threat, only depression was related to optimism and challenge appraisals, while CRF was related mainly to intensity of physical symptoms. The different pattern of associations between optimism and appraisals warrants further clinical attention as well as future study.

Reconstructing baryon oscillations: A Lagrangian theory perspective

NASA Astrophysics Data System (ADS)

Padmanabhan, Nikhil; White, Martin; Cohn, J. D.

2009-03-01

Recently Eisenstein and collaborators introduced a method to “reconstruct” the linear power spectrum from a nonlinearly evolved galaxy distribution in order to improve precision in measurements of baryon acoustic oscillations. We reformulate this method within the Lagrangian picture of structure formation, to better understand what such a method does, and what the resulting power spectra are. We show that reconstruction does not reproduce the linear density field, at second order. We however show that it does reduce the damping of the oscillations due to nonlinear structure formation, explaining the improvements seen in simulations. Our results suggest that the reconstructed power spectrum is potentially better modeled as the sum of three different power spectra, each dominating over different wavelength ranges and with different nonlinear damping terms. Finally, we also show that reconstruction reduces the mode-coupling term in the power spectrum, explaining why miscalibrations of the acoustic scale are reduced when one considers the reconstructed power spectrum.

Archimedes' law explains penetration of solids into granular media.

PubMed

Kang, Wenting; Feng, Yajie; Liu, Caishan; Blumenfeld, Raphael

2018-03-16

Understanding the response of granular matter to intrusion of solid objects is key to modelling many aspects of behaviour of granular matter, including plastic flow. Here we report a general model for such a quasistatic process. Using a range of experiments, we first show that the relation between the penetration depth and the force resisting it, transiently nonlinear and then linear, is scalable to a universal form. We show that the gradient of the steady-state part, K ϕ , depends only on the medium's internal friction angle, ϕ, and that it is nonlinear in μ = tan ϕ, in contrast to an existing conjecture. We further show that the intrusion of any convex solid shape satisfies a modified Archimedes' law and use this to: relate the zero-depth intercept of the linear part to K ϕ and the intruder's cross-section; explain the curve's nonlinear part in terms of the stagnant zone's development.

Depressive symptoms, depression proneness, and outcome expectancies for cigarette smoking.

PubMed

Friedman-Wheeler, Dara G; Ahrens, Anthony H; Haaga, David A F; McIntosh, Elizabeth; Thorndike, Frances P

2007-08-01

The high rates of cigarette smoking among depressed persons may be partially explained by increased positive expectancies for cigarette smoking among this population. In view of theoretical and empirical work on depressed people's negative views of the future, though, it would be expected that depressed smokers would hold particularly negative expectancies about the effects of cigarette smoking. The two current studies examined the relations between depression and smoking outcome expectancies in (a) a general population of adult regular smokers and (b) adult smokers seeking to quit smoking. Depressive symptoms and depression proneness both showed significant positive correlations with positive expectancies for cigarette smoking. Several positive correlations with negative expectancies also emerged. Thus, experiencing depressive symptoms may serve to amplify both favorable and unfavorable expectancies about the effects of smoking.

Women and depression.

PubMed

Betrus, P A; Elmore, S K; Woods, N F; Hamilton, P A

1995-01-01

As Western society increases in complexity and becomes more reliant on technology, women who thrive as integrators in interactional modes will face new dilemmas. Many women will view these changes as challenges, but for many other women, who view these changes as threats, the response will be depression. We lay a foundation to an understanding of depression in women, evaluating the current concept of depression and pointing out its limitations. We then review the traditional theories of women's increased vulnerability to depressive disorders, which have failed to explain adequately this phenomenon. A more recent theory of women's depression, based on the self-in-relation theory of women's development, is offered as an alternative.

Modal method for Second Harmonic Generation in nanostructures

NASA Astrophysics Data System (ADS)

Héron, S.; Pardo, F.; Bouchon, P.; Pelouard, J.-L.; Haïdar, R.

2015-05-01

Nanophotonic devices show interesting features for nonlinear response enhancement but numerical tools are mandatory to fully determine their behaviour. To address this need, we present a numerical modal method dedicated to nonlinear optics calculations under the undepleted pump approximation. It is brie y explained in the frame of Second Harmonic Generation for both plane waves and focused beams. The nonlinear behaviour of selected nanostructures is then investigated to show comparison with existing analytical results and study the convergence of the code.

Higher-order Kerr effect and harmonic cascading in gases.

PubMed

Bache, Morten; Eilenberger, Falk; Minardi, Stefano

2012-11-15

The higher-order Kerr effect (HOKE) has recently been advocated to explain measurements of the saturation of the nonlinear refractive index in gases. Here we show that cascaded third-harmonic generation results in an effective fifth-order nonlinearity that is negative and significant. Higher-order harmonic cascading will also occur from the HOKE, and the cascading contributions may significantly modify the observed nonlinear index change. At lower wavelengths, cascading increases the HOKE saturation intensity, while for longer wavelengths cascading will decrease the HOKE saturation intensity.

Preparation, optical and non-linear optical power limiting properties of Cu, CuNi nanowires

DOE Office of Scientific and Technical Information (OSTI.GOV)

Udayabhaskar, R.; Karthikeyan, B., E-mail: bkarthik@nitt.edu; Ollakkan, Muhamed Shafi

2014-01-06

Metallic nanowires show excellent Plasmon absorption which is tunable based on its aspect ratio and alloying nature. We prepared Cu and CuNi metallic nanowires and studied its optical and nonlinear optical behavior. Optical properties of nanowires are theoretically explained using Gans theory. Nonlinear optical behavior is studied using a single beam open aperture z-scan method with the use of 5 ns Nd: YAG laser. Optical limiting is found to arise from two-photon absorption.

Preparation, optical and non-linear optical power limiting properties of Cu, CuNi nanowires

NASA Astrophysics Data System (ADS)

Udayabhaskar, R.; Ollakkan, Muhamed Shafi; Karthikeyan, B.

2014-01-01

Metallic nanowires show excellent Plasmon absorption which is tunable based on its aspect ratio and alloying nature. We prepared Cu and CuNi metallic nanowires and studied its optical and nonlinear optical behavior. Optical properties of nanowires are theoretically explained using Gans theory. Nonlinear optical behavior is studied using a single beam open aperture z-scan method with the use of 5 ns Nd: YAG laser. Optical limiting is found to arise from two-photon absorption.

Why might poor sleep quality lead to depression? A role for emotion regulation.

PubMed

O'Leary, Kimberly; Bylsma, Lauren M; Rottenberg, Jonathan

2017-12-01

Disordered sleep is strongly linked to future depression, but the reasons for this link are not well understood. This study tested one possibility - that poorer sleep impairs emotion regulation (ER), which over time leads to increased depressive symptoms. Our sample contained individuals with a wide range of depression symptoms (current depression, N = 54, remitted depression, N = 36, and healthy control, N = 53), who were followed clinically over six months and reassessed for changes in depressive symptom levels. As predicted, maladaptive ER mediated both cross-sectional and prospective relationships between poor sleep quality and depression symptoms. In contrast, an alternative mediator, physical activity levels, did not mediate the link between sleep quality and depression symptoms. Maladaptive ER may help explain why sleep difficulties contribute to depression symptoms; implications for interventions are discussed.

Depression: Key to Minority Underachievement.

ERIC Educational Resources Information Center

Rouse, Nancy I.

1980-01-01

This paper explores in depth the possibility that learned helplessness and depression may explain the gap in academic performance between middle-class children and children from minority and poverty backgrounds. Emphasis is placed on Black Americans, because more data is available about this group. (Author/SJL)

Attributional Style and the Freshman Writer.

ERIC Educational Resources Information Center

Gordon, Douglas K.; Mercier, Judith D.

Martin Seligman's psychology research on depression, published in 7 books and hundreds of articles, shows a correlation between attributional style and depression. "Explanatory style" is another term nearly synonymous with attributional style, a habitual way to explain, positively or negatively, external events. A "learned"…

THE FREEZING POINT DEPRESSION OF MAMMALIAN TISSUES AFTER SUDDEN HEATING IN BOILING DISTILLED WATER

PubMed Central

Appelboom, Johannes W. Th.; Brodsky, William A.; Tuttle, William S.; Diamond, Israel

1958-01-01

The calculated freezing point depression of freshly excised boiled mammalian tissue is approximately the same as that of plasma. The boiling procedure was chosen to eliminate the influence of metabolism on the level of the freezing point depression. Problems created by the boiling, such as equilibrium between tissue and diluent, change in activity coefficient by dilution, and loss of CO2 content, are discussed. A frozen crushed tissue homogenate is hypertonic to plasma. Boiling and dilution of such hypertonic homogenate exposed to room temperature for 5 to 15 minutes did not produce significant or unexplicable decreases in its osmotic activity. Moreover, freezing and crushing of a boiled diluted tissue did not produce any increase of the isoosmotic level of freezing point depression. It is possible to explain these data either with the hypothesis of hypertonic cell fluid or with that of isotonic cell fluid. In the case of an assumed isotonic cell fluid, data can be explained with one assumption, experimentally backed. In the case of an assumed hypertonic theory data can be explained only with the help of at least three ad hoc postulates. The data support the validity of the classical concept which holds that cell fluid is isotonic to extracellular fluid. PMID:13563805

Exposure to violence and victimization and depression, hopelessness, and purpose in life among adolescents living in and around public housing.

PubMed

DuRant, R H; Getts, A; Cadenhead, C; Emans, S J; Woods, E R

1995-08-01

This study examines the relationships between exposure to violence and depression, hopelessness, and purpose in life among black adolescents living in or around public housing developments. Black adolescents (N = 225, males = 44%) ages 11 to 19 years in a southern city were administered an anonymous questionnaire. Depression was correlated with the exposure to violence (r = .28), family conflict (r = .29), and corporal punishment (r = .32) scales, perceived probability of being alive at age 25 years (r = -.14), socioeconomic status of head of household (r = .14), anticipated socioeconomic status as an adult (r = .21), and number of sexual partners (r = .22). Based on multiple regression analysis, corporal punishment, family conflict, educational level of head of household, and perceived probability of being alive at age 25 years explained 18% (p < or = .0001) of the variation in depression. Family conflict, corporal punishment, and unemployed head of household explained 11% of the variation in the hopelessness scale. Unemployed head of household, the corporal punishment scale, and number of sexual partners explained 9.7% of the variation in purpose in life. Even when accounting for other social factors, exposure to violence in the home was associated with psychological distress in this sample of adolescents.

Nonlinear simulations of Jupiter's 5-micron hot spots

NASA Technical Reports Server (NTRS)

Showman, A. P.; Dowling, T. E.

2000-01-01

Large-scale nonlinear simulations of Jupiter's 5-micron hot spots produce long-lived coherent structures that cause subsidence in local regions, explaining the low cloudiness and the dryness measured by the Galileo probe inside a hot spot. Like observed hot spots, the simulated coherent structures are equatorially confined, have periodic spacing, propagate west relative to the flow, are generally confined to one hemisphere, and have an anticyclonic gyre on their equatorward side. The southern edge of the simulated hot spots develops vertical shear of up to 70 meters per second in the eastward wind, which can explain the results of the Galileo probe Doppler wind experiment.

Resonant Triad in Boundary-Layer Stability. Part 2; Composite Solution and Comparison with Observations

NASA Technical Reports Server (NTRS)

Mankbadi, Reda R.

1991-01-01

Here, numerical results are computed from an asymptotic near-resonance triad analysis. The analysis considers a resonant triad of instability waves consisting of a plane fundamental wave and a pair of symmetrical oblique subharmonic waves. The relevant scaling ensures that nonlinearity is confined to a distinct critical layer. The analysis is first used to form a composite solution that accounts for both the flow divergence and nonlinear effects. It is shown that the backreaction on the plane Tollmien Schlichting (TS) fundamental wave, although fully accounted for, is of little significance. The observed enhancement at the fundamental frequency disturbance is not in the plane TS wave, but is caused by nonlinearly generated waves at the fundamental frequency that result from nonlinear interactions in the critical layer. The saturation of the oblique waves is caused by their self-interaction. The nonlinear phase-locking phenomenon, the location of resonance with respect to the neutral stability curve, low frequency effects, detuning in the streamwise wave numbers, and nonlinear distortion of the mode shapes are discussed. Nonlinearity modifies the initially two dimensional Blasius profile into a fuller one with spanwise periodicity. The interactions at a wide range of unstable spanwise wave numbers are considered, and the existence of a preferred spanwise wave number is explained by means of the vorticity distribution in the critical layer. Besides presenting novel features of the phenomena and explaining the delicate mechanisms of the interactions, the results of the theory are in excellent agreement with experimental and numerical observations for all stages of the development and for various input parameters.

Kinetic effects on Alfven wave nonlinearity. II - The modified nonlinear wave equation

NASA Technical Reports Server (NTRS)

Spangler, Steven R.

1990-01-01

A previously developed Vlasov theory is used here to study the role of resonant particle and other kinetic effects on Alfven wave nonlinearity. A hybrid fluid-Vlasov equation approach is used to obtain a modified version of the derivative nonlinear Schroedinger equation. The differences between a scalar model for the plasma pressure and a tensor model are discussed. The susceptibilty of the modified nonlinear wave equation to modulational instability is studied. The modulational instability normally associated with the derivative nonlinear Schroedinger equation will, under most circumstances, be restricted to left circularly polarized waves. The nonlocal term in the modified nonlinear wave equation engenders a new modulational instability that is independent of beta and the sense of circular polarization. This new instability may explain the occurrence of wave packet steepening for all values of the plasma beta in the vicinity of the earth's bow shock.

Explaining mental health disparities for non-monosexual women: abuse history and risky sex, or the burdens of non-disclosure?

PubMed

Persson, Tonje J; Pfaus, James G; Ryder, Andrew G

2015-03-01

Research has found that non-monosexual women report worse mental health than their heterosexual and lesbian counterparts. The reasons for these mental health discrepancies are unclear. This study investigated whether higher levels of child abuse and risky sexual behavior, and lower levels of sexual orientation disclosure, may help explain elevated symptoms of depression and anxiety among non-monosexual women. Participants included 388 women living in Canada (Mean age = 24.40, SD = 6.40, 188 heterosexual, 53 mostly heterosexual, 64 bisexual, 32 mostly lesbian, 51 lesbian) who filled out the Beck Depression and Anxiety Inventories as part of an online study running from April 2011 to February 2014. Participants were collapsed into non-monosexual versus monosexual categories. Non-monosexual women reported more child abuse, risky sexual behavior, less sexual orientation disclosure, and more symptoms of depression and anxiety than monosexual women. Statistical mediation analyses, using conditional process modeling, revealed that sexual orientation disclosure and risky sexual behavior uniquely, but not sequentially, mediated the relation between sexual orientation, depression and anxiety. Sexual orientation disclosure and risky sexual behavior were both associated with depression and anxiety. Childhood abuse did not moderate depression, anxiety, or risky sexual behavior. Findings indicate that elevated levels of risky sexual behavior and deflated levels of sexual orientation disclosure may in part explain mental health disparities among non-monosexual women. Results highlight potential targets for preventive interventions aimed at decreasing negative mental health outcomes for non-monosexual women, such as public health campaigns targeting bisexual stigma and the development of sex education programs for vulnerable sexual minority women, such as those defining themselves as bisexual, mostly heterosexual, or mostly lesbian. Copyright © 2014 Elsevier Ltd. All rights reserved.

The role of social support in anxiety and depression among Parkinson's disease patients.

PubMed

Ghorbani Saeedian, Radka; Nagyova, Iveta; Krokavcova, Martina; Skorvanek, Matej; Rosenberger, Jaroslav; Gdovinova, Zuzana; Groothoff, Johan W; van Dijk, Jitse P

2014-01-01

To explore how social support is associated with anxiety and depression in Parkinson's disease (PD) patients controlling for gender, disease duration and disease severity. The sample consisted of 124 patients (52.4% male; mean age 68.1 ± 8.4 years; mean disease duration 6.3 ± 5.5 years). Anxiety and depression were measured with the Hospital Anxiety and Depression Scale, social support with the Multidimensional Scale of Perceived Social Support and disease severity with the Unified Parkinson Disease Rating Scale. Data were analyzed using linear regression. Gender, disease duration, disease severity and social support explained 31% of the total variance in anxiety in younger PD patients but did not significantly contribute to the explanation of depression. In the older group, this model explained 41% of the variance in depression but did not significantly contribute to the explanation of anxiety. PD patients experience the positive influence of social support differently according to age. In the younger group, disease duration plays the primary role regarding anxiety. In the older group, poor social support especially from friends is associated with more depression after controlling for the relevant variables. Implications of Rehabilitation PD is a disease of older age with a neurodegenerative character and treatment should focus on increasing quality of life. Anxiety and depression are common co-morbidities in PD patients. The support network should also be screened regularly and involved in enhancing the quality of life.

Major Depressive Disorder is Associated with Attenuated Cardiovascular Reactivity and Impaired Recovery among Those Free of Cardiovascular Disease

PubMed Central

Salomon, Kristen; Clift, April; Karlsdóttir, Mardís; Rottenberg, Jonathan

2008-01-01

Objective To examine cardiovascular reactivity and recovery to laboratory stress among a naturalistic sample of individuals diagnosed with major depressive disorder (MDD) and healthy control participants. Prospective evidence suggests that MDD confers risk for cardiovascular disease equal to or greater than the risk associated with depressed mood. Enhanced cardiovascular reactivity has been proposed as a mechanism explaining increased risk, but data are inconsistent as to whether depressed individuals exhibit enhanced or attenuated reactivity. Further, few studies have examined appraisal and recovery differences. Design Participants diagnosed with MDD (N = 25) and healthy control participants (N = 25) engaged in a cardiovascular reactivity protocol including two tasks, each followed by a brief recovery period. Main outcome measures Blood pressure, heart rate, pre-ejection period, cardiac output and total peripheral resistance were assessed. Appraisals of tasks were assessed prior to each task. Results Depressed participants exhibited significantly less systolic blood pressure, heart rate and cardiac output reactivity during speech, less heart rate reactivity during mirror tracing and less heart rate recovery after speech and mirror tracing than controls. Depressed participants appraised the tasks as more demanding, threatening, and stressful and reported being less able to cope than controls. Appraisals were related to heart rate reactivity, but appraisals did not mediate the relationship between depression group and reactivity. Conclusion Impaired recovery rather than exaggerated cardiovascular reactivity may partially explain the increased prospective cardiovascular disease risk in depressed individuals. PMID:19290707

Exercise and the Prevention of Depression: Results of the HUNT Cohort Study.

PubMed

Harvey, Samuel B; Øverland, Simon; Hatch, Stephani L; Wessely, Simon; Mykletun, Arnstein; Hotopf, Matthew

2018-01-01

The purpose of the present study was to address 1) whether exercise provides protection against new-onset depression and anxiety and 2) if so, the intensity and amount of exercise required to gain protection and, lastly, 3) the mechanisms that underlie any association. A "healthy" cohort of 33,908 adults, selected on the basis of having no symptoms of common mental disorder or limiting physical health conditions, was prospectively followed for 11 years. Validated measures of exercise, depression, anxiety, and a range of potential confounding and mediating factors were collected. Undertaking regular leisure-time exercise was associated with reduced incidence of future depression but not anxiety. The majority of this protective effect occurred at low levels of exercise and was observed regardless of intensity. After adjustment for confounders, the population attributable fraction suggests that, assuming the relationship is causal, 12% of future cases of depression could have been prevented if all participants had engaged in at least 1 hour of physical activity each week. The social and physical health benefits of exercise explained a small proportion of the protective effect. Previously proposed biological mechanisms, such as alterations in parasympathetic vagal tone, did not appear to have a role in explaining the protection against depression. Regular leisure-time exercise of any intensity provides protection against future depression but not anxiety. Relatively modest changes in population levels of exercise may have important public mental health benefits and prevent a substantial number of new cases of depression.

Similarities in acute phase protein response during hibernation in black bears and major depression in humans: A response to underlying metabolic depression?

USGS Publications Warehouse

Tsiouris, J.A.; Chauhan, V.P.S.; Sheikh, A.M.; Chauhan, A.; Malik, M.; Vaughan, M.R.

2004-01-01

This study investigated the effects of hibernation with mild hypothermia and the stress of captivity on levels of six acute-phase proteins (APPs) in serial samples of serum from 11 wild and 6 captive black bears (Ursus americanus Pallas, 1780) during active and hibernating states. We hypothesize that during hibernation with mild hypothermia, bears would show an APP response similar to that observed in major depression. Enzyme-linked immunoabsorbent assay was used to measure alpha2-macroglobulin and C-reactive protein, and a nephelometer to measure alpha1-antitrypsin, haptoglobin, ceruloplasmin, and transferrin. Levels of all other proteins except ceruloplasmin were significantly elevated during hibernation in both wild and captive bears at the p < 0.05 to p < 0.001 level. Alpha 2-macroglobulin and C-reactive-protein levels were increased in captive versus wild bears in both active and hibernating states at the p < 0.01 to p < 0.0001 level. During hibernation with mild hypothermia, black bears do not show immunosuppression, but show an increased APP response similar to that in patients with major depression. This APP response is explained as an adaptive response to the underlying metabolic depression in both conditions. Metabolic depression in hibernating bears is suggested as a natural model for research to explain the neurobiology of depression.

Course of life satisfaction in patients with depressive and addictive disorders after therapeutic intervention.

PubMed

Büssing, Arndt; Heusser, Peter; Mundle, Götz

2012-05-01

To analyse the course of life satisfaction during the clinic stay of patients with depressive and/or addictive disorders. In a cohort study, 199 patients with depressive and addictive diseases were asked to complete a series of questionnaires at the start and the end of their psychotherapeutic treatment (on average 4.2 ± 2.3 weeks later). The questionnaires were the Brief Multidimensional Life Satisfaction Scale (BMLSS), the Positive Life Construction/Contentedness/Well-Being Scale from the ERDA (Emotional/Rational Disease Acceptance) questionnaire, Beck's Depression Inventory and the revised Symptom Checklist (SCL-90-R). The psychotherapeutic interventions improved the clinical situation of the patients and resulted in strong effects with respect to positive life construction (d = 1.07) and moderate effects on life satisfaction (d = 0.71). Stronger effects were noted in patients with depressive disorders (d = 0.80) than in patients with addictive disorders (d = 0.69). Regression analyses revealed that pre-treatment life satisfaction can be explained negatively by an escape-avoidance strategy (Escape from Illness), and positively by positive life construction. In contrast, post-treatment life satisfaction can be explained negatively by psychological distress and depression, and positively by positive life construction and living with a partner. The hypothesis that life satisfaction changes are associated with the clinical situation of patients was confirmed. In particular, patients with depressive disorders profited from the psychotherapeutic interventions.

Optical polarization based logic functions (XOR or XNOR) with nonlinear Gallium nitride nanoslab.

PubMed

Bovino, F A; Larciprete, M C; Giardina, M; Belardini, A; Centini, M; Sibilia, C; Bertolotti, M; Passaseo, A; Tasco, V

2009-10-26

We present a scheme of XOR/XNOR logic gate, based on non phase-matched noncollinear second harmonic generation from a medium of suitable crystalline symmetry, Gallium nitride. The polarization of the noncollinear generated beam is a function of the polarization of both pump beams, thus we experimentally investigated all possible polarization combinations, evidencing that only some of them are allowed and that the nonlinear interaction of optical signals behaves as a polarization based XOR. The experimental results show the peculiarity of the nonlinear optical response associated with noncollinear excitation, and are explained using the expression for the effective second order optical nonlinearity in noncollinear scheme.

Cooperativity and Heterogeneity in Plastic Crystals Studied by Nonlinear Dielectric Spectroscopy

NASA Astrophysics Data System (ADS)

Michl, M.; Bauer, Th.; Lunkenheimer, P.; Loidl, A.

2015-02-01

The glassy dynamics of plastic-crystalline cyclo-octanol and ortho-carborane, where only the molecular reorientational degrees of freedom freeze without long-range order, is investigated by nonlinear dielectric spectroscopy. Marked differences to canonical glass formers show up: While molecular cooperativity governs the glassy freezing, it leads to a much weaker slowing down of molecular dynamics than in supercooled liquids. Moreover, the observed nonlinear effects cannot be explained with the same heterogeneity scenario recently applied to canonical glass formers. This supports ideas that molecular relaxation in plastic crystals may be intrinsically nonexponential. Finally, no nonlinear effects were detected for the secondary processes in cyclo-octanol.

Association of parental warmth and harsh discipline with developmental trajectories of depressive symptoms among adolescents in Chinese society.

PubMed

Wang, Yu-Chung Lawrence; Chan, Hsun-Yu; Lin, Ching-Wen; Li, Jia-Ru

2015-12-01

This article examines the relationship between parenting styles and the development of depressive symptoms among adolescents. We analyzed a nationally representative longitudinal data set of adolescents aged 12 to 14 in Taiwan. Results from growth mixture modeling revealed a nonlinear increase in the intensity of depressive symptoms between early and middle adolescence. More pronounced depressive symptoms in earlier years were also shown to be associated with more rapid development of similar symptoms later in adolescence. Perceived parenting styles, as manifest in parental warmth and harsh discipline, were categorized into 4 latent heterogeneous classes: attentive, reserved, austere, and conflicting. Adolescents living under austere parenting tend to report the most pronounced depressive symptoms from early to middle adolescence; however, the development of symptoms in this group was the slowest. We also discuss the role of harsh parenting in Chinese culture, as it pertains to the roles traditionally assumed by the father and mother. (c) 2015 APA, all rights reserved).

Mechanisms of Behavior Change in Alcoholics Anonymous: Does AA lead to better alcohol use outcomes by reducing depression symptoms?

PubMed Central

Kelly, John F.; Stout, Robert L.; Magill, Molly; Tonigan, J. Scott; Pagano, Maria E.

2009-01-01

Rationale Indices of negative affect, such as depression, have been implicated in stress-induced pathways to alcohol relapse. Empirically-supported continuing care resources, such as Alcoholics Anonymous (AA), emphasize reducing negative affect to reduce relapse risk, but little research has been conducted to examine putative affective mechanisms of AA’s effects. Method Using lagged, controlled, hierarchical linear modeling and mediational analyses this study investigated whether AA participation mobilized changes in depression symptoms and whether such changes explained subsequent reductions in alcohol use. Alcohol dependent adults (N = 1,706), receiving treatment as part of a clinical trial, were assessed at intake, 3, 6, 9, 12, and 15 months. Results Findings revealed elevated levels of depression compared to the general population, which decreased during treatment and then remained stable over follow-up. Greater AA attendance was associated with better subsequent alcohol use outcomes and decreased depression. Greater depression was associated with heavier and more frequent drinking. Lagged, mediation analyses revealed that the effects of AA on alcohol use was partially mediated by reductions in depression symptoms. However, this salutary effect on depression itself appeared to be explained by AA’s proximal effect on reducing concurrent drinking. Conclusions AA attendance was both concurrently and predictively associated with improved alcohol outcomes. Although AA attendance was additionally associated with subsequent improvements in depression, it did not predict such improvements over and above concurrent alcohol use. AA appears to lead both to improvements in alcohol use and psychological and emotional well-being, which, in turn, may reinforce further abstinence and recovery-related change. PMID:20102345

Factors influencing self-reported vision-related activity limitation in the visually impaired.

PubMed

Tabrett, Daryl R; Latham, Keziah

2011-07-15

The use of patient-reported outcome (PRO) measures to assess self-reported difficulty in visual activities is common in patients with impaired vision. This study determines the visual and psychosocial factors influencing patients' responses to self-report measures, to aid in understanding what is being measured. One hundred visually impaired participants completed the Activity Inventory (AI), which assesses self-reported, vision-related activity limitation (VRAL) in the task domains of reading, mobility, visual information, and visual motor tasks. Participants also completed clinical tests of visual function (distance visual acuity and near reading performance both with and without low vision aids [LVAs], contrast sensitivity, visual fields, and depth discrimination), and questionnaires assessing depressive symptoms, social support, adjustment to visual loss, and personality. Multiple regression analyses identified that an acuity measure (distance or near), and, to a lesser extent, near reading performance without LVAs, visual fields, and contrast sensitivity best explained self-reported VRAL (28%-50% variance explained). Significant psychosocial correlates were depression and adjustment, explaining an additional 6% to 19% unique variance. Dependent on task domain, the parameters assessed explained 59% to 71% of the variance in self-reported VRAL. Visual function, most notably acuity without LVAs, is the best predictor of self-reported VRAL assessed by the AI. Depression and adjustment to visual loss also significantly influence self-reported VRAL, largely independent of the severity of visual loss and most notably in the less vision-specific tasks. The results suggest that rehabilitation strategies addressing depression and adjustment could improve perceived visual disability.

Are Anxiety and Depression Just as Stable as Personality During Late Adolescence? Results From a Three-Year Longitudinal Latent Variable Study

PubMed Central

Prenoveau, Jason M.; Craske, Michelle G.; Zinbarg, Richard E.; Mineka, Susan; Rose, Raphael D.; Griffith, James W.

2012-01-01

Although considerable evidence shows that affective symptoms and personality traits demonstrate moderate to high relative stabilities during adolescence and early adulthood, there has been little work done to examine differential stability among these constructs or to study the manner in which the stability of these constructs is expressed. The present study used a three-year longitudinal design in an adolescent/young adult sample to examine the stability of depression symptoms, social phobia symptoms, specific phobia symptoms, neuroticism, and extraversion. When considering one-, two-, and three-year durations, anxiety and personality stabilities were generally similar and typically greater than the stability of depression. Comparison of various representations of a latent variable trait-state-occasion (TSO) model revealed that whereas the full TSO model was the best representation for depression, a trait stability model was the most parsimonious of the best-fitting models for the anxiety and personality constructs. Over three years, the percentages of variance explained by the trait component for the anxiety and personality constructs (73– 84%) were significantly greater than that explained by the trait component for depression (46%). These findings indicate that symptoms of depression are more episodic in nature, whereas symptoms of anxiety are more similar to personality variables in their expression of stability. PMID:21604827

Depression, family and cellular immunity: Influence of family relationships and cellular immunity on the severity of depression.

PubMed

Zdanowicz, Nicolas; Reynaert, Christine; Jacques, Denis; Tordeurs, David; Lepiece, Brice; Maury, Julien

2015-09-01

Exposure to stress activates the hypothalamic-pituitary-adrenal axis through the release of catecholamines, which modify humoral and cellular immunity. On the one hand, this psycho-immunological theory makes it possible to forge links between immunity and depression. On the other hand, we know that family determinants are an important variable in the model of vulnerability to depression. Our study weighs the influence of cellular immunity and family relations on the severity of depression. 498 inpatients with major depressive disorder were enrolled in an open-label trial. In addition to a socio-demographic questionnaire, they completed Olsen's FACES III and the Beck Depression Inventory (BDI). Flow cytometry was used to assess lymphocyte subsets. In terms of immunity, there are correlations between the BDI and percentages of CD3 (p=0.015; r=-0.112), CD4 (p<0.000; r=-0.175), CD4/CD8 (p=0.045; r=-0.093) and CD16 and 56 (p=0.014; r=0.113). In terms of family relationships, there is a correlation between the BDI and family of origin, both for cohesion (p=0.007; r=-0.169) and adaptability (p=0.035; r=-0.133) measures. With respect to the relationship between family dynamics and immunity, there are correlations between adaptability in the family of origin and CD3 (p=0.04; r=0.094) and CD4 (p=0.044; r=0.093). A logistic regression model for family variables explained 11.4% of the BDI, compared to 12.7% for immune variables, while a model including the two explained 16%. While both the family and immunity can explain the BDI, it is surprising they have a greater effect in combination than individually. This suggests that the psycho-immunological theory should look at the relation between immunity and family life, notably in relation to the family of origin.

Decreased Symptoms of Depression After Mindfulness-Based Stress Reduction: Potential Moderating Effects of Religiosity, Spirituality, Trait Mindfulness, Sex, and Age

PubMed Central

Smoski, Moria J.; Suarez, Edward C.; Brantley, Jeffrey G.; Ekblad, Andrew G.; Lynch, Thomas R.; Wolever, Ruth Quillian

2015-01-01

Abstract Objective: Mindfulness-based stress reduction (MBSR) is a secular meditation training program that reduces depressive symptoms. Little is known, however, about the degree to which a participant's spiritual and religious background, or other demographic characteristics associated with risk for depression, may affect the effectiveness of MBSR. Therefore, this study tested whether individual differences in religiosity, spirituality, motivation for spiritual growth, trait mindfulness, sex, and age affect MBSR effectiveness. Methods: As part of an open trial, multiple regression was used to analyze variation in depressive symptom outcomes among 322 adults who enrolled in an 8-week, community-based MBSR program. Results: As hypothesized, depressive symptom severity decreased significantly in the full study sample (d=0.57; p<0.01). After adjustment for baseline symptom severity, moderation analyses revealed no significant differences in the change in depressive symptoms following MBSR as a function of spirituality, religiosity, trait mindfulness, or demographic variables. Paired t tests found consistent, statistically significant (p<0.01) reductions in depressive symptoms across all subgroups by religious affiliation, intention for spiritual growth, sex, and baseline symptom severity. After adjustment for baseline symptom scores, age, sex, and religious affiliation, a significant proportion of variance in post-MBSR depressive symptoms was uniquely explained by changes in both spirituality (β=−0.15; p=0.006) and mindfulness (β=−0.17; p<0.001). Conclusions: These findings suggest that MBSR, a secular meditation training program, is associated with improved depressive symptoms regardless of affiliation with a religion, sense of spirituality, trait level of mindfulness before MBSR training, sex, or age. Increases in both mindfulness and daily spiritual experiences uniquely explained improvement in depressive symptoms. PMID:25695903

Untangling the Disaster-Depression Knot: The Role of Social Ties After Deepwater Horizon

PubMed Central

Rung, Ariane L.; Gaston, Symielle; Robinson, William T.; Trapido, Edward J.; Peters, Edward S.

2017-01-01

The mental health consequences of disasters, including oil spills, are well known. The goal of this study is to examine whether social capital and social support mediate the effects of exposure to the Deepwater Horizon oil spill on depression among women. Data for the analysis come from the first wave of data collection for the Women and Their Children's Health Study, a longitudinal study of the health effects of women exposed to the oil spill in southern Louisiana, USA. Women were interviewed about their exposure to the oil spill, depression symptoms, structural social capital (neighborhood organization participation), cognitive social capital (sense of community and informal social control), and social support. Structural equation models indicated that structural social capital was associated with increased levels of cognitive social capital, which were associated with higher levels of social support, which in turn were associated with lower levels of depression. Physical exposure to the oil spill was associated with greater economic exposure, which in turn was associated with higher levels of depression. When all variables were taken into account, economic exposure was no longer associated with depression, and social support and cognitive social capital mediated the effect of economic exposure on depression, explaining 67% of the effect. Findings support an extension of the deterioration model of social support to include the additional coping resource of social capital. Social capital and social support were found to be beneficial for depression post-oil spill; however, they were themselves negatively impacted by the oil spill, explaining the overall negative effect of the oil spill on depression. A better understanding of the pathways between the social context and depression could lead to interventions for improved mental health in the aftermath of a disaster. PMID:28152421

Leisure time physical activity, risk of depressive symptoms, and inflammatory mediators: the English Longitudinal Study of Ageing.

PubMed

Hamer, Mark; Molloy, Gerard J; de Oliveira, Cesar; Demakakos, Panayotes

2009-08-01

To examine if inflammatory markers (CRP, fibrinogen) might partly explain the association between physical activity (PA) and risk of depression. The English Longitudinal Study of Ageing, a prospective study of community dwelling older adults. 4323 men and women (aged 63.4+/-9.7 yrs) free from depression at baseline. Self reported leisure time PA levels and depressive symptoms (a score of > or = 4 using the 8-item CES-D scale) were assessed at baseline and 4 yrs follow up. The inflammatory markers, CRP and fibrinogen, were assessed at a 2 yrs intermediate time point between baseline and follow up. At follow up 8% of the sample reported depressive symptomatology. In comparison with participants reporting none or light PA, the odds of depressive symptomatology for those reporting moderate or vigorous PA were 0.71 (95% CI, 0.54-0.95) and 0.58 (0.41-0.81), respectively, after adjustments for baseline CES-D score, age, gender, social-occupational class, smoking, alcohol, and chronic illness. Each standard unit increase in log CRP was associated with higher odds of depressive symptomatology at follow up (1.32, 1.13-1.55) and CRP was inversely associated with physical activity. The association between PA and depressive symptomatology was not, however, substantially modified by further adjustment for CRP (odds for none vs. vigorous PA=0.60, 0.43-0.84). These data suggest that low grade systemic inflammation, as indexed by CRP, is a risk marker for depressive symptomatology, although this mechanism explains only a modest (approximately 5%) amount of the association between PA and risk of depression.

Non-Linear Dynamics of Saturn's Rings

NASA Astrophysics Data System (ADS)

Esposito, L. W.

2016-12-01

Non-linear processes can explain why Saturn's rings are so active and dynamic. Ring systems differ from simple linear systems in two significant ways: 1. They are systems of granular material: where particle-to-particle collisions dominate; thus a kinetic, not a fluid description needed. Stresses are strikingly inhomogeneous and fluctuations are large compared to equilibrium. 2. They are strongly forced by resonances: which drive a non-linear response, that push the system across thresholds that lead to persistent states. Some of this non-linearity is captured in a simple Predator-Prey Model: Periodic forcing from the moon causes streamline crowding; This damps the relative velocity. About a quarter phase later, the aggregates stir the system to higher relative velocity and the limit cycle repeats each orbit, with relative velocity ranging from nearly zero to a multiple of the orbit average. Summary of Halo Results: A predator-prey model for ring dynamics produces transient structures like `straw' that can explain the halo morphology and spectroscopy: Cyclic velocity changes cause perturbed regions to reach higher collision speeds at some orbital phases, which preferentially removes small regolith particles; surrounding particles diffuse back too slowly to erase the effect: this gives the halo morphology; this requires energetic collisions (v ≈ 10m/sec, with throw distances about 200km, implying objects of scale R ≈ 20km).Transform to Duffing Eqn : With the coordinate transformation, z = M2/3, the Predator-Prey equations can be combined to form a single second-order differential equation with harmonic resonance forcing.Ring dynamics and history implications: Moon-triggered clumping explains both small and large particles at resonances. We calculate the stationary size distribution using a cell-to-cell mapping procedure that converts the phase-plane trajectories to a Markov chain. Approximating it as an asymmetric random walk with reflecting boundaries determines the power law index, using results of numerical simulations in the tidal environment. Aggregates can explain many dynamic aspects of the rings and can renew rings by shielding and recycling the material within them, depending on how long the mass is sequestered. We can ask: Are Saturn's rings a chaotic non-linear driven system?

Application of the nonlinear Blinder-Oaxaca decomposition to study racial/ethnic disparities in antiobesity medication use in the United States.

PubMed

Mehta, Hemalkumar B; Rajan, Suja S; Aparasu, Rajender R; Johnson, Michael L

2013-01-01

The nonlinear Blinder-Oaxaca (BO) decomposition method is gaining popularity in health services research because of its ability to explain disparity issues. The present study demonstrates the use of this method for categorical variables by addressing antiobesity medication use disparity. To examine racial/ethnic disparity in antiobesity medication use and to quantify the observed factor contribution behind the disparity using the nonlinear BO decomposition. Medical Expenditure Panel Survey data, 2002-2007, were used in this retrospective cross-sectional study. Adults with body mass index (BMI) >30, or BMI ≥27 and comorbidities such as hypertension, cardiovascular diseases, diabetes, or hyperlipidemia were included in the cohort (N=65,886,625). Multivariable logistic regression was performed to examine racial/ethnic disparity in antiobesity medication use controlling for predisposing, enabling, and need factors. The nonlinear BO decomposition was used to identify the contribution of each predisposing, enabling, and need factors in explaining the racial/ethnic disparity and to estimate the residual unexplained disparity. Non-Hispanic Blacks were 46% (odds ratio [OR]: 0.54; 95% confidence interval [CI]: 0.35-0.83) less likely to use antiobesity drugs compared with non-Hispanic Whites, whereas no difference was observed between Hispanics and non-Hispanic Whites. A 0.22 percentage point of disparity existed between non-Hispanic Whites and Blacks. The nonlinear BO decomposition estimated a decomposition coefficient of -0.0013 indicating that the observed disparity would have been 58% higher (-0.0013/0.0022) if non-Hispanic Blacks had similar observed characteristics as non-Hispanic Whites. Age, gender, marital status, region, and BMI were significant factors in the decomposition model; only marital status explained the racial/ethnic disparity among all observed characteristics. The study revealed that differences in the predisposing, enabling, and need characteristics (except marital status) did not successfully explain the racial/ethnic disparity in antiobesity medication use. Further studies examining racial/ethnic differences in individual beliefs, behavioral patterns, and provider prescription patterns are vital to understand these disparities. Copyright © 2013 Elsevier Inc. All rights reserved.

Non-Linear Dynamics of Saturn’s Rings

NASA Astrophysics Data System (ADS)

Esposito, Larry W.

2015-11-01

Non-linear processes can explain why Saturn’s rings are so active and dynamic. Ring systems differ from simple linear systems in two significant ways: 1. They are systems of granular material: where particle-to-particle collisions dominate; thus a kinetic, not a fluid description needed. We find that stresses are strikingly inhomogeneous and fluctuations are large compared to equilibrium. 2. They are strongly forced by resonances: which drive a non-linear response, pushing the system across thresholds that lead to persistent states.Some of this non-linearity is captured in a simple Predator-Prey Model: Periodic forcing from the moon causes streamline crowding; This damps the relative velocity, and allows aggregates to grow. About a quarter phase later, the aggregates stir the system to higher relative velocity and the limit cycle repeats each orbit.Summary of Halo Results: A predator-prey model for ring dynamics produces transient structures like ‘straw’ that can explain the halo structure and spectroscopy: This requires energetic collisions (v ≈ 10m/sec, with throw distances about 200km, implying objects of scale R ≈ 20km).Transform to Duffing Eqn : With the coordinate transformation, z = M2/3, the Predator-Prey equations can be combined to form a single second-order differential equation with harmonic resonance forcing.Ring dynamics and history implications: Moon-triggered clumping at perturbed regions in Saturn’s rings creates both high velocity dispersion and large aggregates at these distances, explaining both small and large particles observed there. We calculate the stationary size distribution using a cell-to-cell mapping procedure that converts the phase-plane trajectories to a Markov chain. Approximating the Markov chain as an asymmetric random walk with reflecting boundaries allows us to determine the power law index from results of numerical simulations in the tidal environment surrounding Saturn. Aggregates can explain many dynamic aspects of the rings and can renew rings by shielding and recycling the material within them, depending on how long the mass is sequestered. We can ask: Are Saturn’s rings a chaotic non-linear driven system?

Maternal perinatal mental health and offspring academic achievement at age 16: the mediating role of childhood executive function.

PubMed

Pearson, Rebecca M; Bornstein, Marc H; Cordero, Miguel; Scerif, Gaia; Mahedy, Liam; Evans, Jonathan; Abioye, Abu; Stein, Alan

2016-04-01

Elucidating risk pathways for under-achieving at school can inform strategies to reduce the number of adolescents leaving school without passing grades in core subjects. Maternal depression can compromise the quality of parental care and is associated with multiple negative child outcomes. However, only a few small studies have investigated the association between perinatal maternal depression and poor academic achievement in adolescence. The pathways to explain the risks are also unclear. Prospective observational data from 5,801 parents and adolescents taking part in a large UK population cohort (Avon-Longitudinal-Study-of-Parents-and-Children) were used to test associations between maternal and paternal depression and anxiety in the perinatal period, executive function (EF) at age 8, and academic achievement at the end of compulsory school at age 16. Adolescents of postnatally depressed mothers were 1.5 times (1.19, 1.94, p = .001) as likely as adolescents of nondepressed mothers to fail to achieve a 'pass' grade in math; antenatal anxiety was also an independent predictor of poor math. Disruption in different components of EF explained small but significant proportions of these associations: attentional control explained 16% (4%, 27%, p < .001) of the association with postnatal depression, and working memory explained 17% (13%, 30%, p = .003) of the association with antenatal anxiety. A similar pattern was seen for language grades, but associations were confounded by maternal education. There was no evidence that paternal factors were independently associated with impaired child EF or adolescent exams. Maternal postnatal depression and antenatal anxiety are risk factors for adolescents underachieving in math. Preventing, identifying, and treating maternal mental health in the perinatal period could, therefore, potentially increase adolescents' academic achievement. Different aspects of EF partially mediated these associations. Further work is needed, but if these pathways are causal, improving EF could reduce underachievement in math. © 2015 The Authors. Journal of Child Psychology and Psychiatry published by John Wiley & Sons Ltd on behalf of Association for Child and Adolescent Mental Health.

Perfectionism and Ethnicity: Implications for Depressive Symptoms and Self-Reported Academic Achievement.

ERIC Educational Resources Information Center

Castro, Jennifer R.; Rice, Kenneth G.

2003-01-01

Examines ethnic differences in perfectionism among Asian American, African American, and Caucasian American college students. Analyses revealed that Asian American students scored significantly higher than the other groups on perfectionism subscales. Perfectionism explained significant variations in depressive symptoms for Asian Americans and…

Physical activity and common mental disorders.

PubMed

Harvey, Samuel B; Hotopf, Matthew; Overland, Simon; Mykletun, Arnstein

2010-11-01

Previous studies have suggested that physical activity may have antidepressant and/or anti-anxiety effects. To examine the bidirectional relationship between physical activity and common mental disorders and establish the importance of context, type and intensity of activity undertaken. A clinical examination of 40 401 residents of Norway was undertaken. Participants answered questions relating to the frequency and intensity of both leisure-time and workplace activity. Depression and anxiety were measured using the Hospital Anxiety and Depression Scale (HADS). Biological and social data were also collected. There was an inverse relationship between the amount of leisure-time physical activity and case-level symptoms of depression. This cross-sectional association was only present with leisure-time (as opposed to workplace) activity and was not dependent on the intensity of activities undertaken. Higher levels of social support and social engagement were important in explaining the relationship between leisure activity and depression. Biological changes such as alterations to parasympathetic vagal tone (resting pulse) and changes to metabolic markers had a less important role. Individuals who engage in regular leisure-time activity of any intensity are less likely to have symptoms of depression. The context and social benefits of exercise are important in explaining this relationship.

[Impact of attachment style, social support and the number of implantable cardioverter defibrillator (ICD) discharges on psychological strain of ICD patients].

PubMed

Simson, Udo; Perings, Christian; Plaskuda, Ariane; Schäfer, Ralf; Brehm, Michael; Bader, Doris; Tress, Wolfgang; Franz, Matthias

2006-12-01

OBJECTIVE It is well known fact, that the life of ICD patients is often affected by anxiety and depression. The number of ICD discharges is only a contributing factor explaining the variance of anxiety and depression. There have to be other factors that have more influence on the physical strain of ICD patients. In this study we examined the impact of attachment style and social support in addition to the number of ICD discharges. METHODS 119 out-patients at an out-patient ICD unit were examined consecutively with the following self report scales: (1) the State-Trait-Anxiety Inventory (STAI), (2) the Beck Depression Inventory (BDI), (3) a short form of a social support questionnaire (F-SOZU), (4) the Bielefeld Partnership Expectations Questionnaire (BFPE) and (5) a specifically designed questionnaire for the assessment of sociodemografic data. To determine the frequency and timing of the ICD discharges we analysed the ICD data. RESULTS 38 % of the ICD patients reported enhanced anxiety levels and 37 % reported enhanced depression levels. Only 38 % of the ICD patients received discharges at all. Elevated levels of anxiety and depression were found in patients who showed insecure attachment styles, low social support, long-term treatment in hospital and a higher number of ICD discharges. To explain the variance of anxiety we found social support, attachment style, and the number of ICD storms to be contributing factors. To explain the variance of depression we found social support and time spent in hospital in the previous year to be contributing factors. CONCLUSIONS Almost half of the ICD patients suffer considerably from anxiety and/or depression. These patients have to be identified and treated psychotherapeutically. Patients who show insecure attachment styles, receive low social support, undergo long-term treatment in hospital and receive a higher number of discharges, especially so called ICD storms, bear the highest risk to develop psychological strain. Attachment style and social support have even more impact on the development of anxiety and depression than the number of ICD discharges. It has to be shown in future studies whether psychotherapy can improve the quality of life of ICD patients.

Charge of a macroscopic particle in a plasma sheath.

PubMed

Samarian, A A; Vladimirov, S V

2003-06-01

Charging of a macroscopic body levitating in a rf plasma sheath is studied experimentally and theoretically. The nonlinear charge vs size dependence is obtained. The observed nonlinearity is explained on the basis of an approach taking into account different plasma conditions for the levitation positions of different particles. The importance of suprathermal electrons' contribution to the charging process is demonstrated.

Nonlinear Stability and Saturation of Ballooning Modes in Tokamaks*

NASA Astrophysics Data System (ADS)

Ham, C. J.; Cowley, S. C.; Brochard, G.; Wilson, H. R.

2016-06-01

The theory of tokamak stability to nonlinear "ballooning" displacements of elliptical magnetic flux tubes is presented. Above a critical pressure profile the energy stored in the plasma may be lowered by finite (but not infinitesimal) displacements of such tubes (metastability). Above a higher pressure profile, the linear stability boundary, such tubes are linearly and nonlinearly unstable. The predicted saturated flux tube displacement can be of the order of the pressure gradient scale length. Plasma transport from these displaced flux tubes may explain the rapid loss of confinement in some experiments.

The Creative Chaos: Speculations on the Connection Between Non-Linear Dynamics and the Creative Process

NASA Astrophysics Data System (ADS)

Zausner, Tobi

Chaos theory may provide models for creativity and for the personality of the artist. A collection of speculative hypotheses examines the connection between art and such fundamentals of non-linear dynamics as iteration, dissipative processes, open systems, entropy, sensitivity to stimuli, autocatalysis, subsystems, bifurcations, randomness, unpredictability, irreversibility, increasing levels of organization, far-from-equilibrium conditions, strange attractors, period doubling, intermittency and self-similar fractal organization. Non-linear dynamics may also explain why certain individuals suffer mental disorders while others remain intact during a lifetime of sustained creative output.

Impact of initial pulse shape on the nonlinear spectral compression in optical fibre

NASA Astrophysics Data System (ADS)

Boscolo, Sonia; Chaussard, Frederic; Andresen, Esben; Rigneault, Hervé; Finot, Christophe

2018-02-01

We theoretically study the effects of the temporal intensity profile of the initial pulse on the nonlinear propagation spectral compression process arising from nonlinear propagation in an optical fibre. Various linearly chirped input pulse profiles are considered, and their dynamics is explained with the aid of time-frequency representations. While initially parabolic-shaped pulses show enhanced spectral compression compared to Gaussian pulses, no significant spectral narrowing occurs when initially super-Gaussian pulses are used. Triangular pulses lead to a spectral interference phenomenon similar to the Fresnel bi-prism experiment.

Problematic Social Media Use and Depressive Symptoms among U.S. Young Adults: A Nationally-Representative Study

PubMed Central

Shensa, Ariel; Escobar-Viera, César G.; Sidani, Jaime E.; Bowman, Nicholas D.; Marshal, Michael P.; Primack, Brian A.

2017-01-01

Rationale Depression is the leading cause of disability worldwide. The suggested association between social media use (SMU) and depression may be explained by the emerging maladaptive use pattern known as problematic social media use (PSMU), characterized by addictive components. Objective We aimed to assess the association between PSMU and depressive symptoms—controlling for overall time and frequency of SMU—among a large sample of U.S. young adults. Methods In October 2014, participants aged 19–32 (N = 1749) were randomly selected from a nationally-representative U.S. probability-based panel and subsequently invited to participate in an online survey. We assessed depressive symptoms using the validated Patient-Reported Outcomes Measurement Information System (PROMIS) brief depression scale. We measured PSMU using an adapted version of the Bergen Facebook Addiction Scale to encompass broader SMU. Using logistic regression models, we tested the association between PSMU and depressive symptoms, controlling for time and frequency of SMU as well as a comprehensive set of socio-demographic covariates. Results In the multivariable model, PSMU was significantly associated with a 9% increase in odds of depressive symptoms (AOR [adjusted odds ratio] = 1.09; 95% CI [confidence interval]: 1.05, 1.13; p < .001.) Increased frequency of SMU was also significantly associated with increased depressive symptoms, whereas SMU time was not (AOR = 1.01; 95% CI: 1.00, 1.01; p = .001 and AOR = 1.00; 95% CI: 0.999–1.001; p = .43, respectively). Conclusion PSMU was strongly and independently associated with increased depressive symptoms in this nationally-representative sample of young adults. PSMU largely explained the association between SMU and depressive symptom, suggesting that it may be how we use social media, not how much, that poses a risk. Intervention efforts aimed at reducing depressive symptoms, such as screenings for maladaptive SMU, may be most successful if they address addictive components and frequency—rather than time—of SMU. PMID:28446367

Differentials and income-related inequalities in maternal depression during the first two years after childbirth: birth cohort studies from Brazil and the UK.

PubMed

Matijasevich, Alicia; Golding, Jean; Smith, George Davey; Santos, Iná S; Barros, Aluísio Jd; Victora, Cesar G

2009-06-05

Depression is a prevalent health problem among women during the childbearing years. To obtain a more accurate global picture of maternal postnatal depression, studies that explore maternal depression with comparable measurements are needed. The aims of the study are: (1) to compare the prevalence of maternal depression in the first and second year postpartum between a UK and Brazilian birth cohort study; (2) to explore the extent to which variations in the rates were explained by maternal and infant characteristics, and (3) to investigate income-related inequalities in maternal depression after childbirth in both settings. Population-based birth cohort studies were carried out in Avon, UK in 1991 (ALSPAC) and in the city of Pelotas, Brazil in 2004, where 13 798 and 4109 women were analysed, respectively. Self-completion questionnaires were used in the ALSPAC study while questionnaires completed by interviewers were used in the Pelotas cohort study. Three repeated measures of maternal depression were obtained using the Edinburgh Postnatal Depression Scale in the first and second year after delivery in each cohort. Unadjusted and adjusted analyses were carried out. The Relative index of Inequality was used for the analysis of income-relate inequalities so that results were comparable between cohorts. At both the second and third time assessments, the likelihood of being depressed was higher among women from the Pelotas cohort study. These differences were not completely explained by differences in maternal and infant characteristics. Income-related inequalities in maternal depression after childbirth were high and of similar magnitude in both cohort studies at the three time assessments. The burden of maternal depression after childbirth varies between and within populations. Strategies to reduce income-related inequalities in maternal depression should be targeted to low-income women in both developed and developing countries.

Iron and its complexation by phenolic cellular metabolites

PubMed Central

Chobot, Vladimir

2010-01-01

Iron is a transition metal that forms chelates and complexes with various organic compounds, also with phenolic plant secondary metabolites. The ligands of iron affect the redox potential of iron. Electrons may be transferred either to hydroxyl radicals, hydrogen peroxide or molecular oxygen. In the first case, oxidative stress is decreased, in the latter two cases, oxidative stress is increased. This milieu-dependent mode of action may explain the non-linear mode of action of juglone and other secondary metabolites. Attention to this phenomenon may help to explain idiosyncratic and often nonlinear effects that result in biological assays. Current chemical assays are discussed that help to explore these aspects of redox chemistry. PMID:20592800

Pessimism, Trauma, Risky Sex: Covariates of Depression in College Students

ERIC Educational Resources Information Center

Swanholm, Eric; Vosvick, Mark; Chng, Chwee-Lye

2009-01-01

Objective: To explain variance in depression in students (N = 648) using a model incorporating sexual trauma, pessimism, and risky sex. Method: Survey data collected from undergraduate students receiving credit for participation. Results: Controlling for demographics, a hierarchical linear regression analysis [Adjusted R[superscript 2] = 0.34,…

Learning Disability and Depression in Young Adulthood

ERIC Educational Resources Information Center

MacInnes, Maryhelen; Broman, Clifford L.

2013-01-01

It is well established that children and adolescents with learning disabilities are more likely to experience depressed mood than are their peers. Many scholars explain this relationship as resulting from low self-esteem, stress, or social isolation. However, little work has explored whether this relationship continues to exist into young…

Stressful Psychosocial Work Environment, Poor Sleep, and Depressive Symptoms among Primary School Teachers

ERIC Educational Resources Information Center

Gluschkoff, Kia; Elovainio, Marko; Keltikangas-Järvinen, Liisa; Hintsanen, Mirka; Mullola, Sari; Hintsa, Taina

2016-01-01

Introduction: We examined the associations and proportionate contributions of three well-validated models of stressful psychosocial work environment (job strain, effort-reward imbalance, and organizational injustice) in explaining depressive symptoms among primary school teachers. In addition, we tested the mediating role of different types of…

Postnatal Depression. A Review. EUR/HFA Target 8.

ERIC Educational Resources Information Center

World Health Organization, Copenhagen (Denmark). Regional Office for Europe.

This document contains three reports on postnatal depression. The first, "The Maternity Blues," by Flemming Warborg Larsen, presents a literature review on the topic. It concludes that most women look back at the "blues" as an episode that was brief, unpleasant, and difficult to explain. The second report, "Postnatal…

Disruption to the development of maternal responsiveness? The impact of prenatal depression on mother-infant interactions.

PubMed

Pearson, R M; Melotti, R; Heron, J; Joinson, C; Stein, A; Ramchandani, P G; Evans, J

2012-12-01

Both prenatal and postnatal maternal depression are independently associated with an increased risk of adverse infant development. The impact of postnatal depression on infants may be mediated through the effect of depression in reducing maternal responsiveness. However, the mechanisms underlying the effect of prenatal depression are unclear. Using longitudinal data from over 900 mother-infant pairs in a UK birth cohort (ALSPAC), we found that women with high depressive symptom scores during mid pregnancy, but NOT when their infants were 8 months, had a 30% increased risk of low maternal responsiveness when the infant was 12 months compared to women with consistently low depression. This may provide a mechanism to explain the independent association between prenatal depression and poorer infant development. Copyright © 2012 Elsevier Inc. All rights reserved.

The lead-lag relationships between spot and futures prices of natural gas

NASA Astrophysics Data System (ADS)

Zhang, Yahui; Liu, Li

2018-01-01

The lead-lag relationships between spot and futures markets are of great interest for academics. Previous studies neglect the possibility of nonlinear behaviors which may be caused by asymmetry or persistence. To fill this gap, this paper uses the MF-DCCA method and the linear and nonlinear causality tests to explore the causal relationships between natural gas spot and futures prices in the New York Mercantile Exchange. We find that spot and futures prices are positive cross-correlated, the natural gas futures can linearly Granger cause spot price, and there are bidirectional nonlinear causality relationships between natural gas spot and futures prices. Further, we explore the sources of nonlinear causality relationships, and find that the volatility spillover can partly explain the nonlinear causality and affect their cross-correlations.

Religion and the presence and severity of depression in older adults

PubMed Central

Hayward, R. David; Owen, Amy D.; Koenig, Harold G.; Steffens, David C.; Payne, Martha E.

2011-01-01

Objectives To examine the associations of dimensions of religiousness with the presence and severity of depression in older adults. Design Cross-sectional analysis of clinical and interview data. Setting Private university-affiliated medical center in the Southeastern US. Participants Four hundred seventy-six psychiatric patients with a current episode of unipolar major depression, and 167 nondepressed comparison subjects, ages 58 years and older (mean = 70, SD = 7). Measurements Diagnostic Interview Schedule, Montgomery-Åsberg Depression Rating Scale, Duke Depression Evaluation Schedule. Results Presence of depression was related to less frequent worship attendance, more frequent private religious practice, and moderate subjective religiosity. Among the depressed group, less severe depression was related to more frequent worship attendance, less religiousness, and having had a born-again experience. These results were only partially explained by effects of social support and stress buffering. Conclusions Religion is related to depression diagnosis and severity via multiple pathways. PMID:22273738

Religion and the presence and severity of depression in older adults.

PubMed

Hayward, R David; Owen, Amy D; Koenig, Harold G; Steffens, David C; Payne, Martha E

2012-02-01

: To examine the associations of dimensions of religiousness with the presence and severity of depression in older adults. : Cross-sectional analysis of clinical and interview data. : Private university-affiliated medical center in the Southeastern United States. : Four hundred seventy-six psychiatric patients with a current episode of unipolar major depression, and 167 nondepressed comparison subjects, ages 58 years or older (mean = 70 years, SD = 7). : Diagnostic Interview Schedule, Montgomery-Åsberg Depression Rating Scale, and Duke Depression Evaluation Schedule were used in the study. : Presence of depression was related to less frequent worship attendance, more frequent private religious practice, and moderate subjective religiosity. Among the depressed group, less severe depression was related to more frequent worship attendance, less religiousness, and having had a born-again experience. These results were only partially explained by effects of social support and stress buffering. : Religion is related to depression diagnosis and severity via multiple pathways.

Predictors of maternal depression in the first year postpartum: marital status and mediating role of relationship quality.

PubMed

Akincigil, Ayse; Munch, Shari; Niemczyk, Kristen C

2010-01-01

Existing literature has documented the associations between marital status and maternal depression within the first year postpartum. Using data that is representative of urban non-marital births in the United States with a large over-sample of non-marital births, we investigate the association of maternal depression with not only marital status but also relationship quality with the father of the baby. Quality is independently associated with maternal depression after controlling for marital status and other variables that have been documented as risk factors for maternal depression. In addition, relationship quality explains away the associations between marital status and maternal depression. After controlling for relationship quality, single women were no more likely to be depressed compared to married or cohabiting women.

As fathers and felons: explaining the effects of current and recent incarceration on major depression.

PubMed

Turney, Kristin; Wildeman, Christopher; Schnittker, Jason

2012-01-01

Dramatic increases in the American imprisonment rate since the mid-1970s have important implications for the life chances of minority men with low educational attainment, including for their health. Although a large literature has considered the collateral consequences of incarceration for a variety of outcomes, studies concerned with health have several limitations: Most focus exclusively on physical health; those concerned with mental health only consider current incarceration or previous incarceration, but never both; some are cross-sectional; many fail to consider mechanisms; and virtually all neglect the role of family processes, thereby overlooking the social roles current and former prisoners inhabit. In this article, we use stress process theory to extend this research by first considering the association between incarceration and major depression and then considering potential mechanisms that explain this association. Results from the Fragile Families and Child Wellbeing Study (N = 3,107) show current and recent incarceration are substantially associated with the risk of major depression, suggesting both immediate and short-term implications. In addition, consistent with stress proliferation theory, the results show the well-known consequences of incarceration for socioeconomic status and family functioning partly explain these associations, suggesting the link between incarceration and depression depends heavily on the consequences of incarceration for economic and social reintegration, not only the direct psychological consequences of confinement.

Ultra-fast dynamics in the nonlinear optical response of silver nanoprism ordered arrays.

PubMed

Sánchez-Esquivel, Héctor; Raygoza-Sanchez, Karen Y; Rangel-Rojo, Raúl; Kalinic, Boris; Michieli, Niccolò; Cesca, Tiziana; Mattei, Giovanni

2018-03-15

In this work we present the study of the ultra-fast dynamics of the nonlinear optical response of a honeycomb array of silver triangular nanoprisms, performed using a femtosecond pulsed laser tuned with the dipolar surface plasmon resonance of the nanoarray. Nonlinear absorption and refraction, and their time-dependence, were explored using the z-scan and time-resolved excite-probe techniques. Nonlinear absorption is shown to change sign with the input irradiance and the behavior was explained on the basis of a three-level model. The response time was determined to be in the picosecond regime. A technique based on a variable frequency chopper was also used in order to discriminate the thermal and electronic contributions to the nonlinearity, which were found to have opposite signs. All these findings propel the investigated nanoprism arrays as good candidates for applications in advanced ultra-fast nonlinear nanophotonic devices.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kamışlıoğlu, Miraç, E-mail: m.kamislioglu@gmail.com; Külahcı, Fatih, E-mail: fatihkulahci@firat.edu.tr

Nonlinear time series analysis techniques have large application areas on the geoscience and geophysics fields. Modern nonlinear methods are provided considerable evidence for explain seismicity phenomena. In this study nonlinear time series analysis, fractal analysis and spectral analysis have been carried out for researching the chaotic behaviors of release radon gas ({sup 222}Rn) concentration occurring during seismic events. Nonlinear time series analysis methods (Lyapunov exponent, Hurst phenomenon, correlation dimension and false nearest neighbor) were applied for East Anatolian Fault Zone (EAFZ) Turkey and its surroundings where there are about 35,136 the radon measurements for each region. In this paper weremore » investigated of {sup 222}Rn behavior which it’s used in earthquake prediction studies.« less

Explaining risk for suicidal ideation in adolescent offspring of mothers with depression.

PubMed

Hammerton, G; Zammit, S; Thapar, A; Collishaw, S

2016-01-01

It is well-established that offspring of depressed mothers are at increased risk for suicidal ideation. However, pathways involved in the transmission of risk for suicidal ideation from depressed mothers to offspring are poorly understood. The aim of this study was to examine the contribution of potential mediators of this association, including maternal suicide attempt, offspring psychiatric disorder and the parent-child relationship. Data were utilized from a population-based birth cohort (ALSPAC). Three distinct classes of maternal depression symptoms across the first 11 years of the child's life had already been identified (minimal, moderate, chronic-severe). Offspring suicidal ideation was assessed at age 16 years. Data were analysed using structural equation modelling. There was evidence for increased risk of suicidal ideation in offspring of mothers with chronic-severe depression symptoms compared to offspring of mothers with minimal symptoms (odds ratio 3.04, 95% confidence interval 2.19-4.21). The majority of this association was explained through maternal suicide attempt and offspring psychiatric disorder. There was also evidence for an independent indirect effect via the parent-child relationship in middle childhood. There was no longer evidence of a direct effect of maternal depression on offspring suicidal ideation after accounting for all three mediators. The pattern of results was similar when examining mechanisms for maternal moderate depression symptoms. Findings highlight that suicide prevention efforts in offspring of depressed mothers should be particularly targeted at both offspring with a psychiatric disorder and offspring whose mothers have made a suicide attempt. Interventions aimed at improving the parent-child relationship may also be beneficial.

Weight, gender, and depressive symptoms in South Korea

PubMed Central

Han, Seung Yong; SturtzSreetharan, Cindi L.

2017-01-01

Abstract Objectives Obesity consistently predicts depression risk, but the underlying mechanisms are poorly understood. Body concerns are proposed as key. South Korean society is characterized by extremely high levels of explicit weight stigma, possibly the highest globally. Using cross‐sectional Korean 2014 National Health Examination Survey (KNHANES) data, we test this proposition in a nationally representative sample of South Korean adults (N = 5,632). Methods Depressive symptoms (outcome variable), was based on the PHQ‐9. Weight status (predictor variable), was based on direct measures of height and weight converted to BMI. Weight concern was self‐reported. Mediation analyses tested how weight concern mediated the influence of weight status on depressive symptoms for women and men. Results Current weight status influenced depressive symptoms in Korean adults, but not always directly. Concerns of being “fat” mediated that relationship. The effect increased significantly as BMI increased within “normal” and overweight/obese categories for women, and in overweight/obese categories for men. Even though women classified as underweight were significantly more depressed than those in other weight categories, there was no similar mediation effect related to weight concerns. Conclusion For South Koreans, the stress of adhering to social norms and avoiding stigma related to body weight seems to explain the relationship between higher body weight and more depressive symptoms. Women are more vulnerable overall, but men are not immune. This study demonstrates that body concerns help explain why weight predicts depression, and more broadly supports the proposition that widespread weight‐related stigma is a potentially major, if unrecognized, driver of population‐level health disparities. PMID:28161899

Huntingtin gene repeat size variations affect risk of lifetime depression.

PubMed

Gardiner, Sarah L; van Belzen, Martine J; Boogaard, Merel W; van Roon-Mom, Willeke M C; Rozing, Maarten P; van Hemert, Albert M; Smit, Johannes H; Beekman, Aartjan T F; van Grootheest, Gerard; Schoevers, Robert A; Oude Voshaar, Richard C; Roos, Raymund A C; Comijs, Hannie C; Penninx, Brenda W J H; van der Mast, Roos C; Aziz, N Ahmad

2017-12-11

Huntington disease (HD) is a severe neuropsychiatric disorder caused by a cytosine-adenine-guanine (CAG) repeat expansion in the HTT gene. Although HD is frequently complicated by depression, it is still unknown to what extent common HTT CAG repeat size variations in the normal range could affect depression risk in the general population. Using binary logistic regression, we assessed the association between HTT CAG repeat size and depression risk in two well-characterized Dutch cohorts─the Netherlands Study of Depression and Anxiety and the Netherlands Study of Depression in Older Persons─including 2165 depressed and 1058 non-depressed persons. In both cohorts, separately as well as combined, there was a significant non-linear association between the risk of lifetime depression and HTT CAG repeat size in which both relatively short and relatively large alleles were associated with an increased risk of depression (β = -0.292 and β = 0.006 for the linear and the quadratic term, respectively; both P < 0.01 after adjustment for the effects of sex, age, and education level). The odds of lifetime depression were lowest in persons with a HTT CAG repeat size of 21 (odds ratio: 0.71, 95% confidence interval: 0.52 to 0.98) compared to the average odds in the total cohort. In conclusion, lifetime depression risk was higher with both relatively short and relatively large HTT CAG repeat sizes in the normal range. Our study provides important proof-of-principle that repeat polymorphisms can act as hitherto unappreciated but complex genetic modifiers of depression.

The association of minor and major depression with health problem-solving and diabetes self-care activities in a clinic-based population of adults with type 2 diabetes mellitus.

PubMed

Shin, Na; Hill-Briggs, Felicia; Langan, Susan; Payne, Jennifer L; Lyketsos, Constantine; Golden, Sherita Hill

2017-05-01

We examined whether problem-solving and diabetes self-management behaviors differ by depression diagnosis - major depressive disorder (MDD) and minor depressive disorder (MinDD) - in adults with Type 2 diabetes (T2DM). We screened a clinical sample of 702 adults with T2DM for depression, identified 52 positive and a sample of 51 negative individuals, and performed a structured diagnostic psychiatric interview. MDD (n=24), MinDD (n=17), and no depression (n=62) were diagnosed using Diagnostic and Statistical Manual of Mental Disorders IV (DSM-IV) Text Revised criteria. Health Problem-Solving Scale (HPSS) and Summary of Diabetes Self-Care Activities (SDSCA) questionnaires determined problem-solving and T2DM self-management skills, respectively. We compared HPSS and SDSCA scores by depression diagnosis, adjusting for age, sex, race, and diabetes duration, using linear regression. Total HPSS scores for MDD (β=-4.38; p<0.001) and MinDD (β=-2.77; p<0.01) were lower than no depression. Total SDSCA score for MDD (β=-10.1; p<0.01) was lower than for no depression, and was partially explained by total HPSS. MinDD and MDD individuals with T2DM have impaired problem-solving ability. MDD individuals had impaired diabetes self-management, partially explained by impaired problem-solving. Future studies should assess problem-solving therapy to treat T2DM and MinDD and integrated problem-solving with diabetes self-management for those with T2DM and MDD. Copyright © 2017 Elsevier Inc. All rights reserved.

Depression and insomnia are independently associated with satisfaction and enjoyment of life in medication-overuse headache patients.

PubMed

Pompili, Maurizio; Innamorati, Marco; Lamis, Dorian A; Serafini, Gianluca; Ricci, Federica; Migliorati, Monica; Bellini, Samantha; Erbuto, Denise; Mazza, Marianna; Di Nicola, Marco; Janiri, Luigi; Gonda, Xenia; Rihmer, Zoltan; Amore, Mario; Girardi, Paolo; Martelletti, Paolo

2016-07-01

Objective Medication-overuse headache is often comorbid with emotional disturbances and disordered personality traits. The aim of the present study was to determine whether depression and insomnia complaints were associated with satisfaction and enjoyment with one's own life in medication-overuse headache patients, and whether insomnia complaints were able to explain part of the variance of Quality of Life explained by depression. Methods Participants were 187 consecutive adult outpatients admitted to the Regional Referral Headache Centre of the Sant'Andrea Hospital in Rome, Italy. Patients were administered the Quality of Life Enjoyment and Satisfaction Questionnaire, the Beck Depression Inventory - II, and the Athens Insomnia Scale. Results The Beck Depression Inventory was associated with all the dimensions of the Quality of Life Enjoyment and Satisfaction Questionnaire, with more severe depression being associated independently with lower satisfaction and enjoyment with one's own life. The Athens Insomnia Scale was independently and significantly associated only with physical health, such that patients with more insomnia complaints were 3.1 times ( p < 0.001) more likely to report lower physical health satisfaction. Conclusions Our findings confirmed that medication-overuse headache patients has a negative impact on quality of life and suggested that depression and insomnia were independently associated with satisfaction and enjoyment of life in medication-overuse headache patients. The early recognition and appropriate treatment of comorbid psychopathological symptoms are crucial to improve satisfaction and enjoyment of life in medication-overuse headache patients.

Long term effects of childhood trauma on cortisol stress reactivity in adulthood and relationship to the occurrence of depression.

PubMed

Suzuki, Akiko; Poon, Lucia; Papadopoulos, Andrew S; Kumari, Veena; Cleare, Anthony J

2014-12-01

Childhood trauma may have longstanding effects on individuals' propensity to react adversely to stress, and also predisposes individuals to suffer from depression. The current study aimed to examine stress reactivity in individuals with and without a history of childhood trauma by measuring cortisol responses to the passive viewing of stressful images, specifically including images relevant to childhood trauma. In addition, participants with and without a diagnosis of current depression were studied to investigate whether cortisol stress reactivity may underlie resilience or vulnerability to depression. The study involved 17 healthy participants with and 24 without a history of childhood trauma; and 21 depressed patients with and 18 without a history of childhood trauma. Salivary cortisol was measured before, during and after participants were shown affectively laden images, including standardised scenes from the International Affective Picture System and also images suggestive of childhood abuse. Cortisol stress reactivity to the passive image viewing was compared between groups. In those who had experienced childhood trauma, cortisol stress responses were overall low and the same in those who were depressed and those who were not (mean stress reactivity variable - depressed: 0.8 nmol/l; non-depressed: 0.72 nmol/l). In contrast, cortisol stress reactivity was raised in depressed subjects relative to those who were not depressed in those without a history of childhood trauma (mean stress reactivity variable - depressed: 3.75 nmol/l; non-depressed: 0.1 nmol/l). A history of childhood trauma has longstanding effects on adulthood cortisol responses to stress, particularly in that depressed individuals with a history of childhood trauma show blunted cortisol responses. However, there were no differences between abused depressed and abused non-depressed subjects on cortisol stress responses, suggesting that such a finding does not explain subsequent susceptibility to depression. On the other hand, patients who experience depression without a history of childhood trauma show enhanced cortisol stress reactivity, which could help explain the aetiology of their depressive illnesses. Differences between the current findings and those using other pharmacological and stress challenge paradigms may relate to the type of stimuli used and to dysfunction at different levels of the hypothalamic-pituitary-adrenal (HPA) axis. Copyright © 2014 Elsevier Ltd. All rights reserved.

Nonlinear Coherent Structures, Microbursts and Turbulence

NASA Astrophysics Data System (ADS)

Lakhina, G. S.

2015-12-01

Nonlinear waves are found everywhere, in fluids, atmosphere, laboratory, space and astrophysical plasmas. The interplay of nonlinear effects, dispersion and dissipation in the medium can lead to a variety of nonlinear waves and turbulence. Two cases of coherent nonlinear waves: chorus and electrostatic solitary waves (ESWs) and their impact on modifying the plasma medium are discussed. Chorus is a right-hand, circularly-polarized electromagnetic plane wave. Dayside chorus is a bursty emission composed of rising frequency "elements" with duration of ~0.1 to 1.0 s. Each element is composed of coherent subelements with durations of ~1 to 100 ms or more. The cyclotron resonant interaction between energetic electrons and the coherent chorus waves is studied. An expression for the pitch angle transport due to this interaction is derived considering a Gaussian distribution for the time duration of the chorus elements. The rapid pitch scattering can provide an explanation for the ionospheric microbursts of ~0.1 to 0.5 s in bremsstrahlung x-rays formed by ~10-100 keV precipitating electrons. On the other hand, the ESWs are observed in the electric field component parallel to the background magnetic field, and are usually bipolar or tripolar. Generation of coherent ESWs has been explained in terms of nonlinear fluid models of ion- and electron-acoustic solitons and double layers (DLs) based on Sagdeev pseudopotential technique. Fast Fourier transform of electron- and ion-acoustic solitons/DLs produces broadband wave spectra which can explain the properties of the electrostatic turbulence observed in the magnetosheath and plasma sheet boundary layer, and in the solar wind, respectively.

Subjective memory complaints in patients with epilepsy: The role of depression, psychological distress, and attentional functions.

PubMed

Grewe, P; Nikstat, A; Koch, O; Koch-Stoecker, S; Bien, C G

2016-11-01

While objective memory dysfunctions have been thoroughly investigated in patients with epilepsy, assessment of subjective memory complaints (SMC) remains challenging. Former studies have demonstrated an impact of patients' depressive mood on SMC. However, the impact of more general psychological distress and cognitive functioning in non-memory domains on SMC has only received little attention so far. We therefore sought to determine the factors which may particularly predict SMC in a sample of patients with focal epilepsy (n=99) who accomplished (1) a comprehensive neuropsychological assessment, (2) a subjective memory questionnaire, and (3) scales of self-rated depressive mood and psychological distress. General psychological distress (as measured by the Symptom Checklist- 90-Revised) accounted for a high proportion of SMC and, critically, explained more variance than depressive mood as a single factor (as measured by the Beck Depression Inventory II). Furthermore, SMC were predicted by recall measures of a verbal serial learning task, but also by measures of attention, importantly. Hence, our data firstly indicate that beyond the impact of depressive mood, SMC may be more accurately explained by psychological distress in a more general sense. Secondly, our study provides evidence that patients' estimation of subjective memory is not solely based on functioning in memory domains. Attentional resources may also be critical for patients' perception of everyday memory functioning. Copyright © 2016 Elsevier B.V. All rights reserved.

Bidirectional relationship between sleep and optimism with depressive mood as a mediator: A longitudinal study of Chinese working adults.

PubMed

Lau, Esther Yuet Ying; Harry Hui, C; Cheung, Shu-Fai; Lam, Jasmine

2015-11-01

Sleep and optimism are important psycho-biological and personality constructs, respectively. However, very little work has examined the causal relationship between them, and none has examined the potential mechanisms operating in the relationship. This study aimed to understand whether sleep quality was a cause or an effect of optimism, and whether depressive mood could explain the relationship. Internet survey data were collected from 987 Chinese working adults (63.4% female, 92.4% full-time workers, 27.0% married, 90.2% Hong Kong residents, mean age=32.59 at three time-points, spanning about 19 months). Measures included a Chinese attributional style questionnaire, the Pittsburgh Sleep Quality Index, and the Depression Anxiety Stress Scale. Cross-sectional analyses revealed moderate correlations among sleep quality, depressive mood, and optimism. Cross-lagged analyses showed a bidirectional causality between optimism and sleep. Path analysis demonstrated that depressive mood fully mediated the influence of optimism on sleep quality, and it partially mediated the influence of sleep quality on optimism. Optimism improves sleep. Poor sleep makes a pessimist. The effects of sleep quality on optimism could not be fully explained by depressive mood, highlighting the unique role of sleep on optimism. Understanding the mechanisms of the feedback loop of sleep quality, mood, and optimism may provide insights for clinical interventions for individuals presented with mood-related problems. Copyright © 2015 Elsevier Inc. All rights reserved.

Predicting Mood Changes in Bipolar Disorder through Heartbeat Nonlinear Dynamics.

PubMed

Valenza, Gaetano; Nardelli, Mimma; Lanata', Antonio; Gentili, Claudio; Bertschy, Gilles; Kosel, Markus; Scilingo, Enzo Pasquale

2016-04-20

Bipolar Disorder (BD) is characterized by an alternation of mood states from depression to (hypo)mania. Mixed states, i.e., a combination of depression and mania symptoms at the same time, can also be present. The diagnosis of this disorder in the current clinical practice is based only on subjective interviews and questionnaires, while no reliable objective psychophysiological markers are available. Furthermore, there are no biological markers predicting BD outcomes, or providing information about the future clinical course of the phenomenon. To overcome this limitation, here we propose a methodology predicting mood changes in BD using heartbeat nonlinear dynamics exclusively, derived from the ECG. Mood changes are here intended as transitioning between two mental states: euthymic state (EUT), i.e., the good affective balance, and non-euthymic (non-EUT) states. Heart Rate Variability (HRV) series from 14 bipolar spectrum patients (age: 33.439.76, age range: 23-54; 6 females) involved in the European project PSYCHE, undergoing whole night ECG monitoring were analyzed. Data were gathered from a wearable system comprised of a comfortable t-shirt with integrated fabric electrodes and sensors able to acquire ECGs. Each patient was monitored twice a week, for 14 weeks, being able to perform normal (unstructured) activities. From each acquisition, the longest artifact-free segment of heartbeat dynamics was selected for further analyses. Sub-segments of 5 minutes of this segment were used to estimate trends of HRV linear and nonlinear dynamics. Considering data from a current observation at day t0, and past observations at days (t1, t2,...,), personalized prediction accuracies in forecasting a mood state (EUT/non-EUT) at day t+1 were 69% on average, reaching values as high as 83.3%. This approach opens to the possibility of predicting mood states in bipolar patients through heartbeat nonlinear dynamics exclusively.

Anger and depression: evidence of a possible mediating role for rumination.

PubMed

Balsamo, Michela

2010-02-01

Tendency to ruminate may mediate the relationship between anger and depression. In this preliminary study, 353 Italian community participants completed the State-Trait Anger Expression Inventory-2, the Padua Inventory's Tendency to Doubt and to Ruminate subscale, and the Beck Depression Inventory-II. Trait anger and depression were expected to have a positive relationship, and separate relationships with the tendency to ruminate. Theoretically, a new hypothesis was that the tendency to ruminate would mediate the relationship between depression and anger. Zero-order and partial correlations and a path analysis based on Baron and Kenny's method for calculating multiple regression analyses were calculated. Consistent with the hypotheses, anger and depression were strongly associated; the tendency to ruminate was significantly associated with both anger and depression; and the mediation model fit the data. Behaviors related to the tendency to ruminate could help to explain how depression is related to anger.

The depression distress amplification model in adolescents: A longitudinal examination of anxiety sensitivity cognitive concerns, depression and suicidal ideation

PubMed Central

Capron, Daniel W.; Allan, Nicholas P.; Ialongo, Nicholas S.; Leen-Feldner, Ellen; Schmidt, Norman B.

2015-01-01

Adolescents with comorbid anxiety and depression are at significantly increased risk of suicide. The recently proposed depression distress amplification model appears to have promise for explaining the relations between anxiety, depression, and suicidality, but it has not been tested in adolescents. Participants were 524 adolescents followed over two years. Baseline data for the current report were collected by trained interviewers while the adolescents were in eighth grade. Data were obtained in the same manner when the adolescents were in tenth grade. Baseline anxiety sensitivity cognitive concerns significantly predicted suicidal ideation two years later, above and beyond baseline suicidal ideation and depression. Further, consistent with the depression distress amplification model, anxiety sensitivity cognitive concerns interacted with depressive symptoms to predict suicidal ideation. This report extends the empirical and theoretical support for a relationship between anxiety sensitivity cognitive concerns and suicidality. PMID:25754194

Similarity in Depressive Symptoms in Adolescents’ Friendship Dyads: Selection or Socialization?

PubMed Central

Giletta, Matteo; Scholte, Ron H. J.; Burk, William J.; Engels, Rutger C. M. E.; Larsen, Junilla K.; Prinstein, Mitchell J.; Ciairano, Silvia

2012-01-01

This study examined friendship selection and socialization as mechanisms explaining similarity in depressive symptoms in adolescent same-gender best friend dyads. The sample consisted of 1,752 adolescents (51% male) ages 12–16 years (M = 13.77, SD = 0.73) forming 487 friend dyads and 389 nonfriend dyads (the nonfriend dyads served as a comparison group). To test our hypothesis, we applied a multigroup actor–partner interdependence model to 3 friendship types that started and ended at different time points during the 2 waves of data collection. Results showed that adolescents reported levels of depressive symptoms at follow-up that were similar to those of their best friends. Socialization processes explained the increase in similarity exclusively in female dyads, whereas no evidence for friendship selection emerged for either male or female dyads. Additional analyses revealed that similarity between friends was particularly evident in the actual best friend dyads (i.e., true best friends), in which evidence for socialization processes emerged for both female and male friend dyads. Findings highlight the importance of examining friendship relations as a potential context for the development of depressive symptoms. PMID:21639621

Mental Health of Aging Immigrants and Native-Born Men Across 11 European Countries

PubMed Central

2013-01-01

Objectives. Though working-age immigrants exhibit lower mortality compared with those domestic-born immigrants, consequences of immigration for mental health remain unclear. We examine whether older immigrants exhibit a mental advantage and whether factors believed to underlie immigrant vulnerability explain disparities. Method. The sample includes 12,247 noninstitutionalized men more than 50 years in 11 European countries. Multivariate logistic regression models estimated the impact of physical health, health behaviors, availability of social support, social participation, citizenship, time since immigration, socioeconomic status (SES), and employment on the mental health of immigrants. Results. Immigrants face 1.60 increased odds of depression despite a physical health advantage, evidenced by 0.74 lower odds of chronic illness. SES and availability of social support were predictive, though acculturation measures were not. Decomposition analysis revealed that only approximately 20% of the variation in depression rates between immigrants and native-born peers were explained by commonly cited risk factors. Conclusions. Despite physical health advantages, older immigrants suffer substantially higher depression rates. Time since immigration does not appear to mitigate depressive symptoms. PMID:23325505

Nonlinear effective permittivity of field grading composite dielectrics

NASA Astrophysics Data System (ADS)

Yang, Xiao; Zhao, Xiaolei; Li, Qi; Hu, Jun; He, Jinliang

2018-02-01

Field grading composite dielectrics with good nonlinear electrical properties can function as smart materials for electrical field control in a high-voltage apparatus. Besides the well-documented nonlinear conducting behavior, the field-dependent effective permittivity of field grading composites were also reported; however, in-depth research on the mechanism and influencing factors of this nonlinear permittivity are absent. This paper theoretically discusses the origin of the nonlinear effective permittivity, and the mechanism is illustrated through the waveform analysis of the nonlinear response of ZnO microvaristor/silicone rubber composites under a pure AC field. The field-dependent effective permittivity and loss property of the ZnO composites are measured by a dielectric spectrometer in both DC and AC fields under different frequencies. Through comparison of measurement results and theoretical models, the influence of the filler concentration, frequency, and time domain characteristics of the applied field on the nonlinear permittivity of the field grading composites are well explained. This paper provides insight into the nonlinear permittivity of field grading composites, and will be helpful for further tuning the performance of field grading composites.

Boltzmann sampling from the Ising model using quantum heating of coupled nonlinear oscillators.

PubMed

Goto, Hayato; Lin, Zhirong; Nakamura, Yasunobu

2018-05-08

A network of Kerr-nonlinear parametric oscillators without dissipation has recently been proposed for solving combinatorial optimization problems via quantum adiabatic evolution through its bifurcation point. Here we investigate the behavior of the quantum bifurcation machine (QbM) in the presence of dissipation. Our numerical study suggests that the output probability distribution of the dissipative QbM is Boltzmann-like, where the energy in the Boltzmann distribution corresponds to the cost function of the optimization problem. We explain the Boltzmann distribution by generalizing the concept of quantum heating in a single nonlinear oscillator to the case of multiple coupled nonlinear oscillators. The present result also suggests that such driven dissipative nonlinear oscillator networks can be applied to Boltzmann sampling, which is used, e.g., for Boltzmann machine learning in the field of artificial intelligence.

Time-Reversal Generation of Rogue Waves

NASA Astrophysics Data System (ADS)

Chabchoub, Amin; Fink, Mathias

2014-03-01

The formation of extreme localizations in nonlinear dispersive media can be explained and described within the framework of nonlinear evolution equations, such as the nonlinear Schrödinger equation (NLS). Within the class of exact NLS breather solutions on a finite background, which describe the modulational instability of monochromatic wave trains, the hierarchy of rational solutions localized in both time and space is considered to provide appropriate prototypes to model rogue wave dynamics. Here, we use the time-reversal invariance of the NLS to propose and experimentally demonstrate a new approach to constructing strongly nonlinear localized waves focused in both time and space. The potential applications of this time-reversal approach include remote sensing and motivated analogous experimental analysis in other nonlinear dispersive media, such as optics, Bose-Einstein condensates, and plasma, where the wave motion dynamics is governed by the NLS.

Cardiac Vagal Control and Depressive Symptoms in Response to Negative Emotional Stress.

PubMed

Tonhajzerova, I; Visnovcova, Z; Mestanikova, A; Jurko, A; Mestanik, M

We aimed to study complex cardiovagal control using heart rate variability (HRV), linear and nonlinear analyses at rest and during negative emotional stress in healthy students with varying depressive symptoms. ECG recording in 20 students was performed at baseline, negative emotional stress, and recovery period. The HRV parameters evaluated were the following: RR interval, spectral power in high-frequency band (HF-HRV), and symbolic dynamics index 2LV%. The subjects were divided into two groups based on the score of the Beck Depression Inventory (BDI) - normal mood (BDI: 0.6 ± 0.2) and mild mood disturbance (BDI: 14.3 ± 1.4). We found significantly lower logHF-HRV during emotional stress in mild mood disturbance compared with normal mood (p = 0.047). No significant differences were found in the remaining parameters. We conclude that negative emotional stress attenuated the cardiovagal control during mood disturbance, which points to discrete abnormalities in the neurocardiac reflex system associated with depressive symptoms. Hampered cardiovagal control could represent a potential pathomechanism leading to depression-linked cardiovascular complications.

Memory and pattern storage in neural networks with activity dependent synapses

NASA Astrophysics Data System (ADS)

Mejias, J. F.; Torres, J. J.

2009-01-01

We present recently obtained results on the influence of the interplay between several activity dependent synaptic mechanisms, such as short-term depression and facilitation, on the maximum memory storage capacity in an attractor neural network [1]. In contrast with the case of synaptic depression, which drastically reduces the capacity of the network to store and retrieve activity patterns [2], synaptic facilitation is able to enhance the memory capacity in different situations. In particular, we find that a convenient balance between depression and facilitation can enhance the memory capacity, reaching maximal values similar to those obtained with static synapses, that is, without activity-dependent processes. We also argue, employing simple arguments, that this level of balance is compatible with experimental data recorded from some cortical areas, where depression and facilitation may play an important role for both memory-oriented tasks and information processing. We conclude that depressing synapses with a certain level of facilitation allow to recover the good retrieval properties of networks with static synapses while maintaining the nonlinear properties of dynamic synapses, convenient for information processing and coding.

Neighborhood income and major depressive disorder in a large Dutch population: results from the LifeLines Cohort study.

PubMed

Klijs, Bart; Kibele, Eva U B; Ellwardt, Lea; Zuidersma, Marij; Stolk, Ronald P; Wittek, Rafael P M; Mendes de Leon, Carlos M; Smidt, Nynke

2016-08-11

Previous studies are inconclusive on whether poor socioeconomic conditions in the neighborhood are associated with major depressive disorder. Furthermore, conceptual models that relate neighborhood conditions to depressive disorder have not been evaluated using empirical data. In this study, we investigated whether neighborhood income is associated with major depressive episodes. We evaluated three conceptual models. Conceptual model 1: The association between neighborhood income and major depressive episodes is explained by diseases, lifestyle factors, stress and social participation. Conceptual model 2: A low individual income relative to the mean income in the neighborhood is associated with major depressive episodes. Conceptual model 3: A high income of the neighborhood buffers the effect of a low individual income on major depressive disorder. We used adult baseline data from the LifeLines Cohort Study (N = 71,058) linked with data on the participants' neighborhoods from Statistics Netherlands. The current presence of a major depressive episode was assessed using the MINI neuropsychiatric interview. The association between neighborhood income and major depressive episodes was assessed using a mixed effect logistic regression model adjusted for age, sex, marital status, education and individual (equalized) income. This regression model was sequentially adjusted for lifestyle factors, chronic diseases, stress, and social participation to evaluate conceptual model 1. To evaluate conceptual models 2 and 3, an interaction term for neighborhood income*individual income was included. Multivariate regression analysis showed that a low neighborhood income is associated with major depressive episodes (OR (95 % CI): 0.82 (0.73;0.93)). Adjustment for diseases, lifestyle factors, stress, and social participation attenuated this association (ORs (95 % CI): 0.90 (0.79;1.01)). Low individual income was also associated with major depressive episodes (OR (95 % CI): 0.72 (0.68;0.76)). The interaction of individual income*neighborhood income on major depressive episodes was not significant (p = 0.173). Living in a low-income neighborhood is associated with major depressive episodes. Our results suggest that this association is partly explained by chronic diseases, lifestyle factors, stress and poor social participation, and thereby partly confirm conceptual model 1. Our results do not support conceptual model 2 and 3.

Changes in Heart Rate Variability of Depressed Patients after Electroconvulsive Therapy

PubMed Central

Royster, Erica B.; Trimble, Lisa M.; Cotsonis, George; Schmotzer, Brian; Manatunga, Amita; Rushing, Natasha N.; Pagnoni, Giuseppe; Auyeung, S. Freda; Brown, Angelo R.; Schoenbeck, Joel; Murthy, Smitha; McDonald, William M.; Musselman, Dominique L.

2012-01-01

Objective. As few, small studies have examined the impact of electroconvulsive therapy (ECT) upon the heart rate variability of patients with major depressive disorder (MDD), we sought to confirm whether ECT-associated improvement in depressive symptoms would be associated with increases in HRV linear and nonlinear parameters. Methods. After providing consent, depressed study participants (n = 21) completed the Beck Depression Index (BDI), and 15-minute Holter monitor recordings, prior to their 1st and 6th ECT treatments. Holter recordings were analyzed for certain HRV indices: root mean square of successive differences (RMSSD), low-frequency component (LF)/high-frequency component (HF) and short-(SD1) versus long-term (SD2) HRV ratios. Results. There were no significant differences in the HRV indices of RMSDD, LF/HF, and SD1/SD2 between the patients who responded, and those who did not, to ECT. Conclusion. In the short term, there appear to be no significant improvement in HRV in ECT-treated patients whose depressive symptoms respond versus those who do not. Future studies will reveal whether diminished depressive symptoms with ECT are reliably associated with improved sympathetic/parasympathetic balance over the long-term, and whether acute changes in sympathetic/parasympathetic balance predict improved mental- and cardiac-related outcomes. PMID:22966422

Personality traits and psychotic symptoms in recent onset of psychosis patients.

PubMed

Sevilla-Llewellyn-Jones, Julia; Cano-Domínguez, Pablo; de-Luis-Matilla, Antonia; Peñuelas-Calvo, Inmaculada; Espina-Eizaguirre, Alberto; Moreno-Kustner, Berta; Ochoa, Susana

2017-04-01

Personality in patients with psychosis, and particularly its relation to psychotic symptoms in recent onset of psychosis (ROP) patients, is understudied. The aims of this research were to study the relation between dimensional and categorical clinical personality traits and symptoms, as well as the effects that symptoms, sex and age have on clinically significant personality traits. Data for these analyses were obtained from 94 ROP patients. The Millon Clinical Multiaxial Inventory and the Positive and Negative Syndrome Scale were used to assess personality and symptoms. Correlational Analysis, Mann-Whitney test, and, finally, logistic regression were carried out. The negative dimension was higher in patients with schizoid traits. The excited dimension was lower for those with avoidant and depressive traits. The anxiety and depression dimension was higher for patients with dependent traits. The positive dimension was lower for patients with histrionic and higher for patients with compulsive traits. Logistic regression demonstrated that gender and the positive and negative dimensions explained 35.9% of the variance of the schizoid trait. The excited dimension explained 9.1% of the variance of avoidant trait. The anxiety and depression dimension and age explained 31.3% of the dependent trait. Gender explained 11.6% of the histrionic trait, 14.5% of the narcissistic trait and 11.6% of the paranoid trait. Finally gender and positive dimension explained 16.1% of the compulsive trait. The study highlights the importance of studying personality in patients with psychosis as it broadens understating of the patients themselves and the symptoms suffered. Copyright © 2017 Elsevier Inc. All rights reserved.

Unequal depression for equal work? How the wage gap explains gendered disparities in mood disorders.

PubMed

Platt, Jonathan; Prins, Seth; Bates, Lisa; Keyes, Katherine

2016-01-01

Mood disorders, such as depression and anxiety, are more prevalent among women than men. This disparity may be partially due to the effects of structural gender discrimination in the work force, which acts to perpetuate gender differences in opportunities and resources and may manifest as the gender wage gap. We sought to quantify and operationalize the wage gap in order to explain the gender disparity in depression and anxiety disorders, using data from a 2001-2002 US nationally representative survey of 22,581 working adults ages 30-65. Using established Oaxaca-Blinder decomposition methods to account for gender differences in individual-level productivity, our models reduced the wage gap in our sample by 13.5%, from 54% of men's pay to 67.5% of men's pay. We created a propensity-score matched sample of productivity indicators to test if the direction of the wage gap moderated the effects of gender on depression or anxiety. Where female income was less than the matched male counterpart, odds of both disorders were significantly higher among women versus men (major depressive disorder OR: 2.43, 95% CI: 1.95-3.04; generalized anxiety disorder OR: 4.11, 95% CI: 2.80-6.02). Where female income was greater than the matched male, the higher odds ratios for women for both disorders were significantly attenuated (Major Depressive Disorder OR: 1.20; 95% CI: 0.96-1.52) (Generalized Anxiety Disorder OR: 1.5; 95% CI: 1.04-2.29). The test for effect modification by sex and wage gap direction was statistically significant for both disorders. Structural forms of discrimination may explain mental health disparities at the population level. Beyond prohibiting overt gender discrimination, policies must be created to address embedded inequalities in procedures surrounding labor markets and compensation in the workplace. Copyright © 2015 Elsevier Ltd. All rights reserved.

Unequal Depression for Equal Work? How the wage gap explains gendered disparities in mood disorders

PubMed Central

Platt, Jonathan; Prins, Seth; Bates, Lisa; Keyes, Katherine

2016-01-01

Mood disorders, such as depression and anxiety, are more prevalent among women than men. This disparity may be partially due to the effects of structural gender discrimination in the work force, which acts to perpetuate gender differences in opportunities and resources and may manifest as the gender wage gap. We sought to quantify and operationalize the wage gap in order to explain the gender disparity in depression and anxiety disorders, using data from a 2001–2002 US nationally representative survey of 22,581 working adults ages 30–65. Using established Oaxaca-Blinder decomposition methods to account for gender differences in individual-level productivity, our models reduced the wage gap in our sample by 13.5%, from 54% of men’s pay to 67.5% of men’s pay. We created a propensity-score matched sample of productivity indicators to test if the direction of the wage gap moderated the effects of gender on depression or anxiety. Where female income was less than the matched male counterpart, odds of both disorders were significantly higher among women versus men (major depressive disorder OR: 2.43, 95% CI: 1.95–3.04; generalized anxiety disorder OR: 4.11, 95% CI: 2.80–6.02). Where female income was greater than the matched male, the higher odds ratios for women for both disorders were significantly attenuated (Major Depressive Disorder OR: 1.20; 95% CI: 0.96–1.52) (Generalized Anxiety Disorder OR: 1.5; 95% CI: 1.04–2.29). The test for effect modification by sex and wage gap direction was statistically significant for both disorders. Structural forms of discrimination may explain mental health disparities at the population level. Beyond prohibiting overt gender discrimination, policies must be created to address embedded inequalities in procedures surrounding labor markets and compensation in the workplace. PMID:26689629

Perceptual asymmetry in texture perception.

PubMed

Williams, D; Julesz, B

1992-07-15

A fundamental property of human visual perception is our ability to distinguish between textures. A concerted effort has been made to account for texture segregation in terms of linear spatial filter models and their nonlinear extensions. However, for certain texture pairs the ease of discrimination changes when the role of figure and ground are reversed. This asymmetry poses a problem for both linear and nonlinear models. We have isolated a property of texture perception that can account for this asymmetry in discrimination: subjective closure. This property, which is also responsible for visual illusions, appears to be explainable by early visual processes alone. Our results force a reexamination of the process of human texture segregation and of some recent models that were introduced to explain it.

NONLINEAR OPTICAL EFFECTS AND FIBER OPTICS: Modulation of radiation in a fiber Sagnac interferometer induced by an external field

NASA Astrophysics Data System (ADS)

Zakhidov, É. A.; Kasymdzhanov, M. A.; Mirtadzhiev, F. M.; Tartakovskiĭ, G. Kh; Khabibullaev, P. K.

1988-12-01

A study was made of the influence of the Kerr nonlinearity of a fiber waveguide on fluctuations of the output signal from a fiber-optic interferometer. The intensity fluctuations were modeled using the radiation from a pulsed high-power laser with a controlled intensity and pulse profile. Interferograms of the output radiation were obtained for different interferometer configurations. A comparison of the experiment and theory made it possible to explain the observed changes in the signal and to estimate the phase noise due to the Kerr nonlinearity in the investigated fiber waveguide.

A population-based study of anxiety as a precursor for depression in childhood and adolescence.

PubMed

Rice, Frances; van den Bree, Marianne B M; Thapar, Anita

2004-12-13

Anxiety and depression co-occur in children and adolescents with anxiety commonly preceding depression. Although there is some evidence to suggest that the association between early anxiety and later depression is explained by a shared genetic aetiology, the contribution of environmental factors is less well examined and it is unknown whether anxiety itself is a phenotypic risk factor for later depression. These explanations of the association between early anxiety and later depression were evaluated. Anxiety and depressive symptoms were assessed longitudinally in a U.K. population-based sample of 676 twins aged 5-17 at baseline. At baseline, anxiety and depression were assessed by parental questionnaire. Depression was assessed three years later by parental and adolescent questionnaire. Shared genetic effects between early anxiety and later depression were found. A model of a phenotypic risk effect from early anxiety on later depression provided a poor fit to the data. However, there were significant genetic effects specific to later depression, showing that early anxiety and later depression do not index entirely the same genetic risk. Anxiety and depression are associated over time because they share a partly common genetic aetiology rather than because the anxiety phenotype leads to later depression.

Is there an independent association between burnout and increased allostatic load? Testing the contribution of psychological distress and depression.

PubMed

Hintsa, Taina; Elovainio, Marko; Jokela, Markus; Ahola, Kirsi; Virtanen, Marianna; Pirkola, Sami

2016-08-01

Burnout has been suggested to be related to depression. We examined the relationship between burnout and allostatic load, and whether this association is independent of psychological distress and depression. We measured burnout psychological distress, depression, and allostatic load in 3283 participants. Higher burnout (β = 0.06, p =0.003) and cynicism (β = 0.03, p = 0.031) and decreased professional efficacy (β = 0.03, p = 0.007) were related to higher allostatic load independent of age, sex, education, occupation and psychological distress. Depression, however, explained 60 percent of the association. Burnout is related to higher allostatic load, and this association partly overlaps with co-occurring depression. © The Author(s) 2014.

Sex, trauma, stress hormones and depression.

PubMed

Young, E; Korszun, A

2010-01-01

Although few studies dispute that there are gender differences in depression, the etiology is still unknown. In this review, we cover a number of proposed factors and the evidences for and against these factors that may account for gender differences in depression. These include the possible role of estrogens at puberty, differences in exposure to childhood trauma, differences in stress perception between men and women and the biological differences in stress response. None of these factors seem to explain gender differences in depression. Finally, we do know that when depressed, women show greater hypothalamic-pituitary-adrenal (HPA) axis activation than men and that menopause with loss of estrogens show the greatest HPA axis dysregulation. It may be the constantly changing steroid milieu that contributes to these phenomena and vulnerability to depression.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Rumeng; Wang, Lifeng, E-mail: walfe@nuaa.edu.cn

The nonlinear thermal vibration behavior of a single-walled carbon nanotube (SWCNT) is investigated by molecular dynamics simulation and a nonlinear, nonplanar beam model. Whirling motion with energy transfer between flexural motions is found in the free vibration of the SWCNT excited by the thermal motion of atoms where the geometric nonlinearity is significant. A nonlinear, nonplanar beam model considering the coupling in two vertical vibrational directions is presented to explain the whirling motion of the SWCNT. Energy in different vibrational modes is not equal even over a time scale of tens of nanoseconds, which is much larger than the periodmore » of fundamental natural vibration of the SWCNT at equilibrium state. The energy of different modes becomes equal when the time scale increases to the microsecond range.« less

The Role of Nonlinear Gradients in Parallel Imaging: A k-Space Based Analysis.

PubMed

Galiana, Gigi; Stockmann, Jason P; Tam, Leo; Peters, Dana; Tagare, Hemant; Constable, R Todd

2012-09-01

Sequences that encode the spatial information of an object using nonlinear gradient fields are a new frontier in MRI, with potential to provide lower peripheral nerve stimulation, windowed fields of view, tailored spatially-varying resolution, curved slices that mirror physiological geometry, and, most importantly, very fast parallel imaging with multichannel coils. The acceleration for multichannel images is generally explained by the fact that curvilinear gradient isocontours better complement the azimuthal spatial encoding provided by typical receiver arrays. However, the details of this complementarity have been more difficult to specify. We present a simple and intuitive framework for describing the mechanics of image formation with nonlinear gradients, and we use this framework to review some the main classes of nonlinear encoding schemes.

Theory of wing rock

NASA Technical Reports Server (NTRS)

Hsu, C.-H.; Lan, C. E.

1985-01-01

Wing rock is one type of lateral-directional instabilities at high angles of attack. To predict wing rock characteristics and to design airplanes to avoid wing rock, parameters affecting wing rock characteristics must be known. A new nonlinear aerodynamic model is developed to investigate the main aerodynamic nonlinearities causing wing rock. In the present theory, the Beecham-Titchener asymptotic method is used to derive expressions for the limit-cycle amplitude and frequency of wing rock from nonlinear flight dynamics equations. The resulting expressions are capable of explaining the existence of wing rock for all types of aircraft. Wing rock is developed by negative or weakly positive roll damping, and sustained by nonlinear aerodynamic roll damping. Good agreement between theoretical and experimental results is obtained.

How is a specialist depression service effective for persistent moderate to severe depressive disorder?: a qualitative study of service user experience.

PubMed

Thomson, Louise; Barker, Marcus; Kaylor-Hughes, Catherine; Garland, Anne; Ramana, Rajini; Morriss, Richard; Hammond, Emily; Hopkins, Gail; Simpson, Sandra

2018-06-15

A specialist depression service (SDS) offering collaborative pharmacological and cognitive behaviour therapy treatment for persistent depressive disorder showed effectiveness against depression symptoms versus usual community based multidisciplinary care in a randomised controlled trial (RCT) in specialist mental health services in England. However, there is uncertainty concerning how specialist depression services effect such change. The current study aimed to evaluate the factors which may explain the greater effectiveness of SDS compared to Treatment as Usual (TAU) by exploring the experience of the RCT participants. Qualitative audiotaped and transcribed semi-structured interviews were conducted 12-18 months after baseline with 21 service users (12 SDS, 9 TAU arms) drawn from all three sites. Inductive thematic analysis using a grounded approach contrasted the experiences of SDS with TAU participants. Four themes emerged in relation to service user experience: 1. Specific treatment components of the SDS: which included sub-themes of the management of medication change, explaining and developing treatment strategies, setting realistic expectations, and person-centred and holistic approach; 2. Individual qualities of SDS clinicians; 3. Collaborative team context in SDS: which included sub-themes of communication between healthcare professionals, and continuity of team members; 4. Accessibility to SDS: which included sub-themes of flexibility of locations, frequent consultation as reinforcement, gradual pace of treatment, and challenges of returning to usual care. The study uncovered important mechanisms and contextual factors in the SDS that service users experience as different from TAU, and which may explain the greater effectiveness of the SDS: the technical expertise of the healthcare professionals, personal qualities of clinicians, teamwork, gradual pace of care, accessibility and managing service transitions. Usual care in other specialist mental health services may share many of the features from the SDS. "Trial of the Clinical and Cost Effectiveness of a Specialist Expert Mood Disorder Team for Refractory Unipolar Depressive Disorder" was registered in www.ClinicalTrials.gov ( NCT01047124 ) on 12-01-2010 and the ISRCTN registry was registered in www.isrctn.com ( ISRCTN10963342 ) on 25-11-2015 (retrospectively registered).

Antepartum and postpartum exposure to maternal depression: different effects on different adolescent outcomes.

PubMed

Hay, Dale F; Pawlby, Susan; Waters, Cerith S; Sharp, Deborah

2008-10-01

Postpartum depression (PPD) is considered a major public health problem that conveys risk to mothers and offspring. Yet PPD typically occurs in the context of a lifelong episodic illness, and its putative effects might derive from the child's exposure to other episodes, in pregnancy or later childhood. The aim of the study is to test two hypotheses: (1) that the effects of PPD on adolescent outcomes are partly explained by antepartum depression (APD) and (2) that the effects of APD and PPD are both explained by later exposure to the mother's depression. A random sample of 178 antenatal patients was drawn from two general medical practices in South London; 171 gave birth to live infants, and 150 (88%) were assessed at 3 months post partum, with 121 of their offspring (81%) assessed for emotional disorders (ED), disruptive behaviour disorders (DBD) and IQ, at 11 and 16 years of age. When APD and subsequent episodes of depression were taken into account, PPD had a significant effect on adolescent IQ, especially for boys, but did not predict psychopathology. ED and DBD in adolescence were predicted by the extent of exposure to maternal depression after 3 months post partum; a significant effect of APD on ED in girls was accounted for by later exposure to the mother's illness. Mothers' symptoms of anxiety, smoking and alcohol use in pregnancy did not predict adolescent outcomes, once maternal depression was taken into account. Some effects attributed to mothers' mental health problems in pregnancy or post partum may be mediated by cumulative exposure to maternal illness, probably reflecting genetic influence and gene-environment correlation. However, PPD has a direct effect on cognition. Clinicians should endeavour to identify women with depression in pregnancy (31% of this sample) and help them to manage their lifelong illness.

Coffee, tea, caffeine and risk of depression: A systematic review and dose-response meta-analysis of observational studies.

PubMed

Grosso, Giuseppe; Micek, Agnieszka; Castellano, Sabrina; Pajak, Andzrej; Galvano, Fabio

2016-01-01

The aim of the study was to systematically review and analyze results from observational studies on coffee, caffeine, and tea consumption and association or risk of depression. Embase and PubMed databases were searched from inception to June 2015 for observational studies reporting the odds ratios or relative risks (RRs) and 95% confidence intervals (CI) of depression by coffee/tea/caffeine consumption. Random effects models, subgroup analyses, and dose-response analyses were performed. Twelve studies with 23 datasets were included in the meta-analysis, accounting for a total of 346 913 individuals and 8146 cases of depression. Compared to individuals with lower coffee consumption, those with higher intakes had pooled RR of depression of 0.76 (95% CI: 0.64, 0.91). Dose-response effect suggests a nonlinear J-shaped relation between coffee consumption and risk of depression with a peak of protective effect for 400 mL/day. A borderline nonsignificant association between tea consumption and risk of depression was found (RR 0.70, 95% CI: 0.48, 1.01), while significant results were found only for analysis of prospective studies regarding caffeine consumption (RR = 0.84, 95% CI: 0.75, 0.93). This study suggests a protective effect of coffee and, partially, of tea and caffeine on risk of depression. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The mediating role of dichotomous thinking and emotional eating in the relationship between depression and BMI.

PubMed

Antoniou, Evangelia E; Bongers, Peggy; Jansen, Anita

2017-08-01

Obesity and depression have important health implications. Although there is knowledge about the moderators of the depression-obesity association, our understanding of the potential behavioral and cognitive mediators that may explain the relationship between depression and obesity, is scarcely researched. The aim of this study is to investigate the mediating role of emotional eating and dichotomous thinking in the depression-obesity relationship. Data on 205 individuals from a community-based study conducted at Maastricht University, Netherlands were used. Self-reported data on depression, emotional eating and dichotomous thinking were collected and BMI scores were calculated in a cross-sectional research design. Correlations between variables were calculated. The primary analysis tested the hypothesis that depression has an effect on BMI through dichotomous thinking and emotional eating. A two-mediator model was used to predict the direct and indirect effects of emotional eating and dichotomous thinking on the depression-BMI relationship. Depression was positively correlated with BMI (r=0.21, p=0.005), emotional eating (r=0.38, p<0.001) and dichotomous thinking (r=0.49, p<0.001). Dichotomous thinking and emotional eating were positively correlated with BMI (r=0.35, p<0.001; and r=0.45, p<0.001 respectively). Both dichotomous thinking (Z=2.54, p=0.01, 95% confidence intervals=0.01-0.17) and emotional eating (Z=3.92 p<0.001, 95% confidence intervals=0.06-0.19) could explain the depression-BMI relationship. The assessment of emotional eating and dichotomous thinking might be useful in guiding assessment and treatment protocols for weight management. The present study adds to the existing literature on the role of dysfunctional cognitions and emotions on eating behavior, and particularly to the factors that may impede people's ability to control their eating. Copyright © 2017 Elsevier Ltd. All rights reserved.

Nonlinear Transport in Organic Thin Film Transistors with Soluble Small Molecule Semiconductor.

PubMed

Kim, Hyeok; Song, Dong-Seok; Kwon, Jin-Hyuk; Jung, Ji-Hoon; Kim, Do-Kyung; Kim, SeonMin; Kang, In Man; Park, Jonghoo; Tae, Heung-Sik; Battaglini, Nicolas; Lang, Philippe; Horowitz, Gilles; Bae, Jin-Hyuk

2016-03-01

Nonlinear transport is intensively explained through Poole-Frenkel (PF) transport mechanism in organic thin film transistors with solution-processed small molecules, which is, 6,13-bis(triisopropylsilylethynyl) (TIPS) pentacene. We outline a detailed electrical study that identifies the source to drain field dependent mobility. Devices with diverse channel lengths enable the extensive exhibition of field dependent mobility due to thermal activation of carriers among traps.

Periodic nonlinear waves resulting from the contact interaction of a crack

NASA Astrophysics Data System (ADS)

Lee, Sang Eon; Jin, Suyeong; Hong, Jung-Wuk

2017-09-01

When two different inputs of distinct low and high frequencies are applied to a medium, the linear responses are composed of waves of two dominant frequencies. However, microcracks such as fatigue cracks generate nonlinear waves by modulating the characteristics of the incident waves. Although this phenomenon has been observed and used to detect microcracks, the underlying principles have not been thoroughly elucidated. The hysteresis properties were introduced to describe the nonlinear relationship between the stress and strain to explain these phenomena [Van Den Abeele et al., Res. Nondestruct. Eval. 12, 17 (2000) and Nazarov et al., Acoust. Phys. 49, 344 (2003)]. The generation of harmonics was explained by superimposing stress-strain relations that vary with crack width and excitation magnitude. As the crack depth increases, the ratio of magnitudes of the second harmonic to the first harmonic increases, but the increment becomes smaller [Kawashima et al., Ultrasonics 40, 611 (2002)]. Here, we show that the waves affected by the contact motion of the crack surfaces cultivate the nonlinearity in waveforms, resulting in high frequency off-band signals. With the hypothesis that the clapping of cracks might generate nonlinear components close to the high excitation frequency, we prove that the generation of the high frequency off-band peaks is directly affected by the clapping contact interaction of the crack surfaces. The amount of energy transmitted is closely related to the size of the crack width and the magnitudes of low and high frequency excitations.

Adaptation of non-linear mixed amount with zero amount response surface model for analysis of concentration-dependent synergism and safety with midazolam, alfentanil, and propofol sedation.

PubMed

Liou, J-Y; Ting, C-K; Teng, W-N; Mandell, M S; Tsou, M-Y

2018-06-01

The non-linear mixed amount with zero amounts response surface model can be used to describe drug interactions and predict loss of response to noxious stimuli and respiratory depression. We aimed to determine whether this response surface model could be used to model sedation with the triple drug combination of midazolam, alfentanil and propofol. Sedation was monitored in 56 patients undergoing gastrointestinal endoscopy (modelling group) using modified alertness/sedation scores. A total of 227 combinations of effect-site concentrations were derived from pharmacokinetic models. Accuracy and the area under the receiver operating characteristic curve were calculated. Accuracy was defined as an absolute difference <0.5 between the binary patient responses and the predicted probability of loss of responsiveness. Validation was performed with a separate group (validation group) of 47 patients. Effect-site concentration ranged from 0 to 108 ng ml -1 for midazolam, 0-156 ng ml -1 for alfentanil, and 0-2.6 μg ml -1 for propofol in both groups. Synergy was strongest with midazolam and alfentanil (24.3% decrease in U 50 , concentration for half maximal drug effect). Adding propofol, a third drug, offered little additional synergy (25.8% decrease in U 50 ). Two patients (3%) experienced respiratory depression. Model accuracy was 83% and 76%, area under the curve was 0.87 and 0.80 for the modelling and validation group, respectively. The non-linear mixed amount with zero amounts triple interaction response surface model predicts patient sedation responses during endoscopy with combinations of midazolam, alfentanil, or propofol that fall within clinical use. Our model also suggests a safety margin of alfentanil fraction <0.12 that avoids respiratory depression after loss of responsiveness. Copyright © 2018 British Journal of Anaesthesia. Published by Elsevier Ltd. All rights reserved.

The association between Diabetes mellitus and Depression.

PubMed

Bădescu, S V; Tătaru, C; Kobylinska, L; Georgescu, E L; Zahiu, D M; Zăgrean, A M; Zăgrean, L

2016-01-01

Depression occurrence is two to three times higher in people with diabetes mellitus, the majority of the cases remaining under-diagnosed. The purpose of this review was to show the links between depression and diabetes, point out the importance of identifying depression in diabetic patients and identify the possible ways to address both diseases. Possible common pathophysiological mechanisms as stress and inflammation were explained, while emphasis was made on screening for depression in diabetic patients. An important aspect for the diabetic specialist would be the understanding of the common origins of diabetes and depression and the awareness of this quite common comorbidity, in order to improve the outcomes of both diseases. DALYS = disability adjusted life years, DSM-5 = American Psychiatric Association Diagnostic and Statistical Manual of Mental Disorders, DM1 = Type 1 diabetes mellitus, DM2 = Type 2 diabetes mellitus, HPA-axis = hypothalamus - pituitary - adrenal axis, SNS = sympathetic nervous system, BDI = Beck Depression Inventory, CES-D = Centre for Epidemiologic Studies Depression Scale, HADS = Hospital Anxiety and Depression Scale, PHQ = Patient Health Questionnaire.

The Psychosocial Context Impacts Medication Adherence after Acute Coronary Syndrome

PubMed Central

Kronish, Ian M.; Rieckmann, Nina; Burg, Matthew M.; Alcántara, Carmela; Davidson, Karina W.

2013-01-01

Background Depression is associated with poor adherence to medications and worse prognosis in patients with acute coronary syndrome (ACS). Purpose To determine whether cognitive, behavioral, and/or psychosocial vulnerabilities for depression explain the association between depression and medication adherence among ACS patients. Methods 169 ACS patients who agreed to have their aspirin adherence measured using an electronic pill bottle for 3 months were enrolled within 1 week of hospitalization. Linear regression was used to determine whether depression vulnerabilities predicted aspirin adherence after adjustment for depressive symptoms, demographics, and comorbidity. Results Of the depression vulnerabilities, only role transitions (beta = −3.32; p=0.02) and interpersonal conflict (beta −3.78; p=0.03) predicted poor adherence. Depression vulnerabilities did not mediate the association between depressive symptoms and medication adherence. Conclusions Key elements of the psychosocial context preceding the ACS including major role transitions and conflict with close contacts place ACS patients at increased risk for poor medication adherence independent of depressive symptoms. PMID:24163188

Prevalence, Work-Loss Days and Quality of Life of Community Dwelling Subjects with Depressive Symptoms

PubMed Central

Sohn, Jee Hoon; Ahn, Seung Hee; Seong, Su Jeong; Ryu, Ji Min

2013-01-01

The nationwide prevalence of major depressive disorder in Korea is lower than most countries, despite the high suicide rate. To explain this unexpectedly low prevalence, we examined the functional disability and quality of life in community-dwelling subjects with significant depressive symptoms not diagnosable as depressive disorder. A total of 1,029 subjects, randomly chosen from catchment areas, were interviewed with the Center for Epidemiologic Studies Depression scale, Mini International Neuropsychiatric Interview, WHO Quality of Life scale, and the WHO Disability Assessment Schedule. Those with scores over 21 on the depression scale were interviewed by a psychiatrist for diagnostic confirmation. Among community-dwelling subjects, the 1-month prevalence of major depressive disorder was 2.2%, but the 1-month prevalence of depressive symptoms not diagnosable as depressive disorder was 14.1%. Depressive disorders were the cause of 24.7% of work loss days, while depressive symptoms not diagnosable as depressive disorder were the cause of 17.2% of work loss days. These findings support the dimensional or spectrum approach to depressive disorder in the community and might be the missing link between the apparent low prevalence of depressive disorder and high suicide rate in Korea. PMID:23399785

Specific cognitive functions and depressive symptoms as predictors of activities of daily living in older adults with heterogeneous cognitive backgrounds

PubMed Central

de Paula, Jonas J.; Diniz, Breno S.; Bicalho, Maria A.; Albuquerque, Maicon Rodrigues; Nicolato, Rodrigo; de Moraes, Edgar N.; Romano-Silva, Marco A.; Malloy-Diniz, Leandro F.

2015-01-01

Cognitive functioning influences activities of daily living (ADL). However, studies reporting the association between ADL and neuropsychological performance show inconsistent results regarding what specific cognitive domains are related to each specific functional domains. Additionally, whether depressive symptoms are associated with a worse functional performance in older adults is still under explored. We investigated if specific cognitive domains and depressive symptoms would affect different aspects of ADL. Participants were 274 older adults (96 normal aging participants, 85 patients with mild cognitive impairment, and 93 patients probable with mild Alzheimer’s disease dementia) with low formal education (∼4 years). Measures of ADL included three complexity levels: Self-care, Instrumental-Domestic, and Instrumental-Complex. The specific cognitive functions were evaluated through a factorial strategy resulting in four cognitive domains: Executive Functions, Language/Semantic Memory, Episodic Memory, and Visuospatial Abilities. The Geriatric Depression Scale measured depressive symptoms. Multiple linear regression analysis showed executive functions and episodic memory as significant predictors of Instrumental-Domestic ADL, and executive functions, episodic memory and language/semantic memory as predictors of Instrumental-Complex ADL (22 and 28% of explained variance, respectively). Ordinal regression analysis showed the influence of specific cognitive functions and depressive symptoms on each one of the instrumental ADL. We observed a heterogeneous pattern of association with explained variance ranging from 22 to 38%. Different instrumental ADL had specific cognitive predictors and depressive symptoms were predictive of ADL involving social contact. Our results suggest a specific pattern of influence depending on the specific instrumental daily living activity. PMID:26257644

Progressive epicardial coronary blood flow reduction fails to produce ST-segment depression at normal heart rates.

PubMed

de Chantal, Marilyn; Diodati, Jean G; Nasmith, James B; Amyot, Robert; LeBlanc, A Robert; Schampaert, Erick; Pharand, Chantal

2006-12-01

ST-segment depression is commonly seen in patients with acute coronary syndromes. Most authors have attributed it to transient reductions in coronary blood flow due to nonocclusive thrombus formation on a disrupted atherosclerotic plaque and dynamic focal vasospasm at the site of coronary artery stenosis. However, ST-segment depression was never reproduced in classic animal models of coronary stenosis without the presence of tachycardia. We hypothesized that ST-segment depression occurring during acute coronary syndromes is not entirely explained by changes in epicardial coronary artery resistance and thus evaluated the effect of a slow, progressive epicardial coronary artery occlusion on the ECG and regional myocardial blood flow in anesthetized pigs. Slow, progressive occlusion over 72 min (SD 27) of the left anterior descending coronary artery in 20 anesthetized pigs led to a 90% decrease in coronary blood flow and the development of ST-segment elevation associated with homogeneous and transmural myocardial blood flow reductions, confirmed by microspheres and myocardial contrast echocardiography. ST-segment depression was not observed in any ECG lead before the development of ST-segment elevation. At normal heart rates, progressive epicardial stenosis of a coronary artery results in myocardial ischemia associated with homogeneous, transmural reduction in regional myocardial blood flow and ST-segment elevation, without preceding ST-segment depression. Thus, in coronary syndromes with ST-segment depression and predominant subendocardial ischemia, factors other than mere increases in epicardial coronary resistance must be invoked to explain the heterogeneous parietal distribution of flow and associated ECG changes.

Resting-state EEG delta power is associated with psychological pain in adults with a history of depression.

PubMed

Meerwijk, Esther L; Ford, Judith M; Weiss, Sandra J

2015-02-01

Psychological pain is a prominent symptom of clinical depression. We asked if frontal alpha asymmetry, frontal EEG power, and frontal fractal dimension asymmetry predicted psychological pain in adults with a history of depression. Resting-state frontal EEG (F3/F4) was recorded while participants (N=35) sat upright with their eyes closed. Frontal delta power predicted psychological pain while controlling for depressive symptoms, with participants who exhibited less power experiencing greater psychological pain. Frontal fractal dimension asymmetry, a nonlinear measure of complexity, also predicted psychological pain, such that greater left than right complexity was associated with greater psychological pain. Frontal alpha asymmetry did not contribute unique variance to any regression model of psychological pain. As resting-state delta power is associated with the brain's default mode network, results suggest that the default mode network was less activated during high psychological pain. Findings are consistent with a state of arousal associated with psychological pain. Copyright © 2015 Elsevier B.V. All rights reserved.

Temperamental factors in remitted depression: The role of effortful control and attentional mechanisms.

PubMed

Marchetti, Igor; Shumake, Jason; Grahek, Ivan; Koster, Ernst H W

2018-08-01

Temperamental effortful control and attentional networks are increasingly viewed as important underlying processes in depression and anxiety. However, it is still unknown whether these factors facilitate depressive and anxiety symptoms in the general population and, more specifically, in remitted depressed individuals. We investigated to what extent effortful control and attentional networks (i.e., Attention Network Task) explain concurrent depressive and anxious symptoms in healthy individuals (n = 270) and remitted depressed individuals (n = 90). Both samples were highly representative of the US population. Increased effortful control predicted a substantial decrease in symptoms of both depression and anxiety in the whole sample, whereas decreased efficiency of executive attention predicted a modest increase in depressive symptoms. Remitted depressed individuals did not show less effortful control nor less efficient attentional networks than healthy individuals. Moreover, clinical status did not moderate the relationship between temperamental factors and either depressive or anxiety symptoms. Limitations include the cross-sectional nature of the study. Our study shows that temperamental effortful control represents an important transdiagnostic process for depressive and anxiety symptoms in adults. Copyright © 2018 Elsevier B.V. All rights reserved.

The Longitudinal Relationship between the Use of Long-Term Care and Depressive Symptoms in Older Adults

ERIC Educational Resources Information Center

Pot, Anne Margriet; Deeg, Dorly J.H.; Twisk, Jos W.R.; Beekman, Aartjan T.F.; Zarit, Steven H.

2005-01-01

Purpose: The aim of this study was to estimate the longitudinal relationship between transitions in the use of long-term care and older adults' depressive symptoms and to investigate whether this relationship could be explained by markers of older adults' underlying health, or other variables including demographics, personality, and partner…

The Interrelations of Agency, Depression, and Suicidal Ideation among Older Adults

ERIC Educational Resources Information Center

Hobbs, Mitchell; McLaren, Suzanne

2009-01-01

The high rates of suicide among older men are cause for concern, and have prompted the investigation of factors that might explain these elevated rates. The current research examined whether the gender role construct agency was associated with depression and suicidal ideation among older adults. The results, based on self-report data from a sample…

Poverty and Depression among Men: The Social Class Worldview Model and Counseling Implications.

ERIC Educational Resources Information Center

Liu, William M.

This paper outlines a theory for understanding social class in men's lives, and argues that poverty and depression are a function of social class and internalized classism. It begins by defining poverty, then explains the Social Class Worldview Model, which is a subjective social class model, and the Modern Classism Theory, which allows clinicians…

The Applicability of Cognitive Mediational and Moderational Models to Explain Children's Depression Inventory Factor Scores in Urban Youth

ERIC Educational Resources Information Center

Reinemann, Dawn H. S.; Teeter Ellison, Phyllis A.

2004-01-01

This investigation examined whether cognition serves as a direct factor, mediates, or moderates the relationship between stressful life events and Children's Depression Inventory (CDI; Kovacs, 1992) factor scores in urban, ethnic minority youth. Ninety-eight middle school students completed measures of stressful life events, cognition (cognitive…

Suicidal Ideation, Depression, and Conduct Disorder in a Sample of Adolescent and Young Adult Twins

ERIC Educational Resources Information Center

Linker, Julie; Gillespie, Nathan A.; Maes, Hermine; Eaves, Lindon; Silberg, Judy L.

2012-01-01

The co-occurrence of suicidal ideation, depression, and conduct disturbance is likely explained in part by correlated genetic and environmental risk factors. Little is known about the specific nature of these associations. Structured interviews on 2,814 twins from the Virginia Twin Study of Adolescent Behavioral Development (VTSABD) and Young…

Similarity in Depressive Symptoms in Adolescents' Friendship Dyads: Selection or Socialization?

ERIC Educational Resources Information Center

Giletta, Matteo; Scholte, Ron H. J.; Burk, William J.; Engels, Rutger C. M. E.; Larsen, Junilla K.; Prinstein, Mitchell J.; Ciairano, Silvia

2011-01-01

This study examined friendship selection and socialization as mechanisms explaining similarity in depressive symptoms in adolescent same-gender best friend dyads. The sample consisted of 1,752 adolescents (51% male) ages 12-16 years (M = 13.77, SD = 0.73) forming 487 friend dyads and 389 nonfriend dyads (the nonfriend dyads served as a comparison…

Differential Exposure and Reactivity to Interpersonal Stress Predict Sex Differences in Adolescent Depression

ERIC Educational Resources Information Center

Shih, Josephine H.; Eberhart, Nicole K.; Hammen, Constance L.; Brennan, Patricia A.

2006-01-01

This study tested the hypothesis that higher rates of depression in adolescent girls are explained by their greater exposure and reactivity to stress in the interpersonal domain in a large sample of 15-year-olds. Findings indicate that adolescent girls experienced higher levels of total and interpersonal episodic stress, whereas boys experienced…

The Structure of Anxiety and Depression in a Normative Sample of Younger and Older Australian Adolescents

ERIC Educational Resources Information Center

Tully, Phillip J.; Zajac, Ian T.; Venning, Anthony J.

2009-01-01

It has been reported that depression and anxiety have overlapping symptoms and are conceptually interrelated. One of the most prominent theoretical developments that explain this association is Clark and Watson's tripartite model ("Journal of Abnormal Psychology," 100:316-336, 1991) that posits these two disorders and negative emotions…

Landscape characteristics and coho salmon (Oncorhynchus kisutch) distributions: explaining abundance versus occupancy

Treesearch

E.A. Steel; D.W. Jensen; K.M. Burnett; K. Christiansen; J.C. Firman; B.E. Feist; K.J. Anlauf; D.P. Larsen

2012-01-01

Distribution of fishes, both occupancy and abundance, is often correlated with landscape-scale characteristics (e.g., geology, climate, and human disturbance). Understanding these relationships is essential for effective conservation of depressed populations. We used landscape characteristics to explain the distribution of coho salmon (Oncorhynchus kisutch...

A Study of Remitted and Treatment-Resistant Depression Using MMPI and Including Pessimism and Optimism Scales

PubMed Central

Suzuki, Masatoshi; Takahashi, Michio; Muneoka, Katsumasa; Sato, Koichi; Hashimoto, Kenji; Shirayama, Yukihiko

2014-01-01

Background The psychological aspects of treatment-resistant and remitted depression are not well documented. Methods We administered the Minnesota Multiphasic Personality Inventory (MMPI) to patients with treatment-resistant depression (n = 34), remitted depression (n = 25), acute depression (n = 21), and healthy controls (n = 64). Pessimism and optimism were also evaluated by MMPI. Results ANOVA and post-hoc tests demonstrated that patients with treatment-resistant and acute depression showed similarly high scores for frequent scale (F), hypochondriasis, depression, conversion hysteria, psychopathic device, paranoia, psychasthenia and schizophrenia on the MMPI compared with normal controls. Patients with treatment-resistant depression, but not acute depression registered high on the scale for cannot say answer. Using Student's t-test, patients with remitted depression registered higher on depression and social introversion scales, compared with normal controls. For pessimism and optimism, patients with treatment-resistant depression demonstrated similar changes to acutely depressed patients. Remitted depression patients showed lower optimism than normal controls by Student's t-test, even though these patients were deemed recovered from depression using HAM-D. Conclusions The patients with remitted depression and treatment-resistant depression showed subtle alterations on the MMPI, which may explain the hidden psychological features in these cohorts. PMID:25279466

Unmasking materialistic depression as a mental health problem: its effect on depression and materialism in an African-United States undergraduate sample.

PubMed

Azibo, Daudi Ajani ya

2013-09-05

Misdiagnosis of African-U.S. persons is argued to be a built-in characteristic of Western-based assessment requiring augmentation with culture-focused input where possible. Regarding depression, materialistic depression is explained as an African-centered African-U.S. culture-focused construct of masked depression. Materialistic depression symptomatology is presented. Materialism orientation is postulated to necessarily be associated with materialistic depression. 144 undergraduates, 37 male (25.7%) and 107 female (74.3%), average age of 21 completed the Zung Self-rating Depression Scale, the depression subscale of the Symptom Checklist 90-R, the materialism subscale of the Cultural Misorientation Scale, and the Materialistic Depression Quiz. Contrasting high versus lower scoring MDQ groups on both depression scores produced reliable t-tests (p<.017). One-way ANOVA on materialism scores with high, medium, low MDQ groups was reliable (p<.017). The sample precluded generalization to clinically depressed and non-college African-U.S. populations. Using the Materialistic Depression Quiz, high scorers versus medium and low scorers had greater depression scores on two depression measures and greater materialism scores. Materialistic depression appears a masked form of depression not to be overlooked. Copyright © 2013 Elsevier B.V. All rights reserved.

[Predictive factors of depression in adolescents at school: the role of implicit theories of intelligence].

PubMed

Da Fonseca, D; Cury, F; Rufo, M; Poinso, F

2007-10-01

The aim of this study was to complete the identification of predictive factors of depression during adolescence. For some authors, depression is characterized by a style of attribution, which consists essentially in attributing most of the negative outcomes to internal, stable, and uncontrollable factors. It seems that these attributions depend essentially on the type of their beliefs and in particular, those concerning the nature of intelligence. These beliefs called "implicit theories of intelligence", are the entity theory of intelligence and the incremental theory of intelligence. The entity theory of intelligence corresponds to the belief according to which intelligence is the expression of a relatively stable, fixed, and noncontrollable feature, and which we cannot change. In contrast, the incremental theory corresponds to the belief according to which intelligence is a controllable quality, which we can develop through effort and work. Several studies have demonstrated that the adolescents who consider intelligence as a malleable quality explain their bad results by internal, unstable, and controllable factors. Conversely, students who consider intelligence as a fixed capacity tend to strongly attribute their failure to internal, stable, and uncontrollable factors. We have consequently formulated the hypothesis according to which the entity theory should be a predictive factor of depression. We have also tested the fact that anxiety should be a mediating factor within the relation between the entity theory and depression. The sample was composed of 424 adolescents. Using different questionnaires, we measured implicit theories of the intelligence (TIDI), self-esteem (EES), anxiety (STAI-Form Y-B) and depression (CDI). Multiple regression analyses demonstrated that the entity theory of intelligence positively predicts depression. Self-esteem negatively predicts anxiety and depression. Moreover, anxiety is a mediator of the relation between self-esteem and depression, on one hand, and the relation between the entity theory of intelligence and depression, on the other. Finally, the effect of the entity theory of intelligence appears to be modulated by the level of self-esteem. This study explains the mechanisms by which the implicit theories of intelligence engender anxiety and depression. Furthermore, this approach provides interesting perspectives in the prevention and management of adolescents presenting depression.

Problematic social media use and depressive symptoms among U.S. young adults: A nationally-representative study.

PubMed

Shensa, Ariel; Escobar-Viera, César G; Sidani, Jaime E; Bowman, Nicholas D; Marshal, Michael P; Primack, Brian A

2017-06-01

Depression is the leading cause of disability worldwide. The suggested association between social media use (SMU) and depression may be explained by the emerging maladaptive use pattern known as problematic social media use (PSMU), characterized by addictive components. We aimed to assess the association between PSMU and depressive symptoms-controlling for overall time and frequency of SMU-among a large sample of U.S. young adults. In October 2014, participants aged 19-32 (N = 1749) were randomly selected from a nationally-representative U.S. probability-based panel and subsequently invited to participate in an online survey. We assessed depressive symptoms using the validated Patient-Reported Outcomes Measurement Information System (PROMIS) brief depression scale. We measured PSMU using an adapted version of the Bergen Facebook Addiction Scale to encompass broader SMU. Using logistic regression models, we tested the association between PSMU and depressive symptoms, controlling for time and frequency of SMU as well as a comprehensive set of socio-demographic covariates. In the multivariable model, PSMU was significantly associated with a 9% increase in odds of depressive symptoms (AOR [adjusted odds ratio] = 1.09; 95% CI [confidence interval]: 1.05, 1.13; p < 0.001.) Increased frequency of SMU was also significantly associated with increased depressive symptoms, whereas SMU time was not (AOR = 1.01; 95% CI: 1.00, 1.01; p = 0.001 and AOR = 1.00; 95% CI: 0.999-1.001; p = 0.43, respectively). PSMU was strongly and independently associated with increased depressive symptoms in this nationally-representative sample of young adults. PSMU largely explained the association between SMU and depressive symptom, suggesting that it may be how we use social media, not how much, that poses a risk. Intervention efforts aimed at reducing depressive symptoms, such as screenings for maladaptive SMU, may be most successful if they address addictive components and frequency-rather than time-of SMU. Copyright © 2017 Elsevier Ltd. All rights reserved.

Personality and Depression: Explanatory Models and Review of the Evidence

PubMed Central

Klein, Daniel N.; Kotov, Roman; Bufferd, Sara J.

2012-01-01

Understanding the association between personality and depression has implications for elucidating etiology and comorbidity, identifying at-risk individuals, and tailoring treatment. We discuss seven major models that have been proposed to explain the relation between personality and depression, and we review key methodological issues, including study design, the heterogeneity of mood disorders, and the assessment of personality. We then selectively review the extensive empirical literature on the role of personality traits in depression in adults and children. Current evidence suggests that depression is linked to traits such as neuroticism/negative emotionality, extraversion/positive emotionality, and conscientiousness. Moreover, personality characteristics appear to contribute to the onset and course of depression through a variety of pathways. Implications for prevention and prediction of treatment response are discussed, as well as specific considerations to guide future research on the relation between personality and depression. PMID:21166535

Depressive thoughts limit working memory capacity in dysphoria.

PubMed

Hubbard, Nicholas A; Hutchison, Joanna L; Turner, Monroe; Montroy, Janelle; Bowles, Ryan P; Rypma, Bart

2016-01-01

Dysphoria is associated with persistence of attention on mood-congruent information. Longer time attending to mood-congruent information for dysphoric individuals (DIs) detracts from goal-relevant information processing and should reduce working memory (WM) capacity. Study 1 showed that DIs and non-DIs have similar WM capacities. Study 2 embedded depressive information into a WM task. Compared to non-DIs, DIs showed significantly reduced WM capacity for goal-relevant information in this task. Study 3 replicated results from Studies 1 and 2, and further showed that DIs had a significantly greater association between processing speed and recall on the depressively modified WM task compared to non-DIs. The presence of inter-task depressive information leads to DI-related decreased WM capacity. Results suggest dysphoria-related WM capacity deficits when depressive thoughts are present. WM capacity deficits in the presence of depressive thoughts are a plausible mechanism to explain day-to-day memory and concentration difficulties associated with depressed mood.

Coping Strategies and Depression Among College Students Following Child Sexual Abuse in Turkey.

PubMed

Yılmaz Irmak, Türkan; Aksel, Şeyda; Thompson, Dennis

2016-01-01

The objective of this study was to investigate the relationship between type of coping style and depression in college students with child sexual abuse experience. A total of 1,055 college students completed self-report measures to assess depressive symptoms, coping strategies, and child sexual abuse history. This study was conducted with a subset of 125 college students who reported that they had been sexually abused in childhood. They were divided into depressive and nondepressive groups according to their depressive symptoms. Data was collected with the Childhood Sexual Abuse Measurement, the Beck Depression Inventory, and the Coping Styles of Stress Scale. Family characteristics were measured with a demographic questionnaire. Analyses involved multiple regression to test for predictive effects. Among college students with child sexual abuse histories, parental education level and both problem-focused and emotion-focused strategies significantly explained depression scores.

Cardiovascular Disease, Psychosocial Factors, and Genetics: The Case of Depression

PubMed Central

Mulle, Jennifer Gladys; Vaccarino, Viola

2013-01-01

Psychosocial factors are associated with cardiovascular disease, but little is known about the role of genetics in this relationship. Focusing on the well-studied phenotype of depression, current data show that there are shared genetic factors that may give rise to both depression and CVD, and these genetic risks appear to be modified by gender. This pleiotropic effect suggests that a single pathway, when perturbed, gives rise to the dual phenotypes of CVD and depression. The data also suggest that women contribute disproportionately to the depression-CVD comorbidity, and this unbalanced contribution is attributable, in part, to genetic factors. While the underlying biology behind this relationship is unclear, recent data support contributions from inflammatory or serotonergic pathways toward the comorbidity between CVD and depression. Even without knowledge of a specific mechanism, epidemiological observations offer new directions to explain the relationship between depression and CVD that have both research and clinical applications. PMID:23621965

Is major depressive episode related to anxiety disorders in anorexics and bulimics?

PubMed

Godart, Nathalie T; Perdereau, Fabienne; Curt, Florence; Rein, Zoé; Lang, François; Venisse, Jean Luc; Halfon, Olivier; Bizouard, Paul; Loas, Gwenole; Corcos, Maurice; Jeammet, Philippe; Flament, Martine F

2006-01-01

To determine whether the presence of anxiety disorders is related to depressive comorbidity in subjects with eating disorders (ED), while taking into account certain variables that may be related to depression (subjects' age, ED duration, prior incidents of anorexia nervosa in bulimic subjects, inpatient or outpatient status, nutritional state [as measured by body mass index]). We evaluated the frequency of depressive disorders in 271 subjects presenting with a diagnosis of either anorexia nervosa or bulimia, using the Mini International Neuropsychiatric Interview, DSM-IV version. A multivariate analysis reveals that anxiety disorders do not all have the same influence in terms of risk of onset of major depressive episode in anorexics and bulimics when adjusted on variables related to depression. Depression in subjects with ED can be explained in part by comorbidity with obsessive-compulsive disorder, generalized anxiety, social phobia, and panic disorder.

Work environment stressors, social support, anxiety, and depression among secondary school teachers.

PubMed

Mahan, Pamela L; Mahan, Michael P; Park, Na-Jin; Shelton, Christie; Brown, Kathleen C; Weaver, Michael T

2010-05-01

Work environment stress, a salient health and safety issue for secondary school teachers, school administrators, parents, and students, was examined in 168 teachers from two urban and five suburban high schools. The purpose of this study was to examine relationships between ongoing and episodic stressors and anxiety and depression, as well as the extent to which anxiety and depression may be predicted by stressors and coworker and supervisor support. The Ongoing Stressor Scale (OSS) and the Episodic Stressor Scale (ESS), the Coworker and Supervisor Contents of Communication Scales (COCS), the State Anxiety inventory (S-Anxiety), and the Center for Epidemiological Studies Depression Scale (CES-D) were used to measure the variables. Ongoing and episodic stressors were significantly and positively associated with anxiety and depression. Ongoing stressors and coworker support were significant in explaining anxiety and depression among secondary school teachers. Coworker support had an inverse relationship to anxiety and depression.

Diabetes and Depression

PubMed Central

de Groot, Mary; Golden, Sherita Hill

2015-01-01

Diabetes and depression occur together approximately twice as frequently as would be predicted by chance alone. Comorbid diabetes and depression are a major clinical challenge as the outcomes of both conditions are worsened by the other. Although the psychological burden of diabetes may contribute to depression, this explanation does not fully explain the relationship between these 2 conditions. Both conditions may be driven by shared underlying biological and behavioral mechanisms, such as hypothalamic-pituitary-adrenal axis activation, inflammation, sleep disturbance, inactive lifestyle, poor dietary habits, and environmental and cultural risk factors. Depression is frequently missed in people with diabetes despite effective screening tools being available. Both psychological interventions and antidepressants are effective in treating depressive symptoms in people with diabetes but have mixed effects on glycemic control. Clear care pathways involving a multidisciplinary team are needed to obtain optimal medical and psychiatric outcomes for people with comorbid diabetes and depression. PMID:24743941

Influence of laminate sequence and fabric type on the inherent acoustic nonlinearity in carbon fiber reinforced composites.

PubMed

Chakrapani, Sunil Kishore; Barnard, Daniel J; Dayal, Vinay

2016-05-01

This paper presents the study of influence of laminate sequence and fabric type on the baseline acoustic nonlinearity of fiber-reinforced composites. Nonlinear elastic wave techniques are increasingly becoming popular in detecting damage in composite materials. It was earlier observed by the authors that the non-classical nonlinear response of fiber-reinforced composite is influenced by the fiber orientation [Chakrapani, Barnard, and Dayal, J. Acoust. Soc. Am. 137(2), 617-624 (2015)]. The current study expands this effort to investigate the effect of laminate sequence and fabric type on the non-classical nonlinear response. Two hypotheses were developed using the previous results, and the theory of interlaminar stresses to investigate the influence of laminate sequence and fabric type. Each hypothesis was tested by capturing the nonlinear response by performing nonlinear resonance spectroscopy and measuring frequency shifts, loss factors, and higher harmonics. It was observed that the laminate sequence can either increase or decrease the nonlinear response based on the stacking sequence. Similarly, tests were performed to compare unidirectional fabric and woven fabric and it was observed that woven fabric exhibited a lower nonlinear response compared to the unidirectional fabric. Conjectures based on the matrix properties and interlaminar stresses were used in an attempt to explain the observed nonlinear responses for different configurations.

Building Blocks for Reliable Complex Nonlinear Numerical Simulations

NASA Technical Reports Server (NTRS)

Yee, H. C.; Mansour, Nagi N. (Technical Monitor)

2002-01-01

This talk describes some of the building blocks to ensure a higher level of confidence in the predictability and reliability (PAR) of numerical simulation of multiscale complex nonlinear problems. The focus is on relating PAR of numerical simulations with complex nonlinear phenomena of numerics. To isolate sources of numerical uncertainties, the possible discrepancy between the chosen partial differential equation (PDE) model and the real physics and/or experimental data is set aside. The discussion is restricted to how well numerical schemes can mimic the solution behavior of the underlying PDE model for finite time steps and grid spacings. The situation is complicated by the fact that the available theory for the understanding of nonlinear behavior of numerics is not at a stage to fully analyze the nonlinear Euler and Navier-Stokes equations. The discussion is based on the knowledge gained for nonlinear model problems with known analytical solutions to identify and explain the possible sources and remedies of numerical uncertainties in practical computations. Examples relevant to turbulent flow computations are included.

Building Blocks for Reliable Complex Nonlinear Numerical Simulations

NASA Technical Reports Server (NTRS)

Yee, H. C.

2005-01-01

This chapter describes some of the building blocks to ensure a higher level of confidence in the predictability and reliability (PAR) of numerical simulation of multiscale complex nonlinear problems. The focus is on relating PAR of numerical simulations with complex nonlinear phenomena of numerics. To isolate sources of numerical uncertainties, the possible discrepancy between the chosen partial differential equation (PDE) model and the real physics and/or experimental data is set aside. The discussion is restricted to how well numerical schemes can mimic the solution behavior of the underlying PDE model for finite time steps and grid spacings. The situation is complicated by the fact that the available theory for the understanding of nonlinear behavior of numerics is not at a stage to fully analyze the nonlinear Euler and Navier-Stokes equations. The discussion is based on the knowledge gained for nonlinear model problems with known analytical solutions to identify and explain the possible sources and remedies of numerical uncertainties in practical computations.

Building Blocks for Reliable Complex Nonlinear Numerical Simulations. Chapter 2

NASA Technical Reports Server (NTRS)

Yee, H. C.; Mansour, Nagi N. (Technical Monitor)

2001-01-01

This chapter describes some of the building blocks to ensure a higher level of confidence in the predictability and reliability (PAR) of numerical simulation of multiscale complex nonlinear problems. The focus is on relating PAR of numerical simulations with complex nonlinear phenomena of numerics. To isolate sources of numerical uncertainties, the possible discrepancy between the chosen partial differential equation (PDE) model and the real physics and/or experimental data is set aside. The discussion is restricted to how well numerical schemes can mimic the solution behavior of the underlying PDE model for finite time steps and grid spacings. The situation is complicated by the fact that the available theory for the understanding of nonlinear behavior of numerics is not at a stage to fully analyze the nonlinear Euler and Navier-Stokes equations. The discussion is based on the knowledge gained for nonlinear model problems with known analytical solutions to identify and explain the possible sources and remedies of numerical uncertainties in practical computations. Examples relevant to turbulent flow computations are included.

Nonlinear Midinfrared Photothermal Spectroscopy Using Zharov Splitting and Quantum Cascade Lasers.

PubMed

Mertiri, Alket; Altug, Hatice; Hong, Mi K; Mehta, Pankaj; Mertz, Jerome; Ziegler, Lawrence D; Erramilli, Shyamsunder

2014-08-20

We report on the mid-infrared nonlinear photothermal spectrum of the neat liquid crystal 4-octyl-4'-cyanobiphenyl (8CB) using a tunable Quantum Cascade Laser (QCL). The nonequilibrium steady state characterized by the nonlinear photothermal infrared response undergoes a supercritical bifurcation. The bifurcation, observed in heterodyne two-color pump-probe detection, leads to ultrasharp nonlinear infrared spectra similar to those reported in the visible region. A systematic study of the peak splitting as a function of absorbed infrared power shows the bifurcation has a critical exponent of 0.5. The observation of an apparently universal critical exponent in a nonequilibrium state is explained using an analytical model analogous of mean field theory. Apart from the intrinsic interest for nonequilibrium studies, nonlinear photothermal methods lead to a dramatic narrowing of spectral lines, giving rise to a potential new contrast mechanism for the rapidly emerging new field of mid-infrared microspectroscopy using QCLs.

Nonlinear Midinfrared Photothermal Spectroscopy Using Zharov Splitting and Quantum Cascade Lasers

PubMed Central

2015-01-01

We report on the mid-infrared nonlinear photothermal spectrum of the neat liquid crystal 4-octyl-4′-cyanobiphenyl (8CB) using a tunable Quantum Cascade Laser (QCL). The nonequilibrium steady state characterized by the nonlinear photothermal infrared response undergoes a supercritical bifurcation. The bifurcation, observed in heterodyne two-color pump–probe detection, leads to ultrasharp nonlinear infrared spectra similar to those reported in the visible region. A systematic study of the peak splitting as a function of absorbed infrared power shows the bifurcation has a critical exponent of 0.5. The observation of an apparently universal critical exponent in a nonequilibrium state is explained using an analytical model analogous of mean field theory. Apart from the intrinsic interest for nonequilibrium studies, nonlinear photothermal methods lead to a dramatic narrowing of spectral lines, giving rise to a potential new contrast mechanism for the rapidly emerging new field of mid-infrared microspectroscopy using QCLs. PMID:25541620

Nonlinear Landau damping in the ionosphere

NASA Technical Reports Server (NTRS)

Kiwamoto, Y.; Benson, R. F.

1978-01-01

A model is presented to explain the non-resonant waves which give rise to the diffuse resonance observed near 3/2 f sub H by the Alouette and ISIS topside sounders, where f sub H is the ambient electron cyclotron frequency. In a strictly linear analysis, these instability driven waves will decay due to Landau damping on a time scale much shorter than the observed time duration of the diffuse resonance. Calculations of the nonlinear wave particle coupling coefficients, however, indicate that the diffuse resonance wave can be maintained by the nonlinear Landau damping of the sounder stimulated 2f sub H wave. The time duration of the diffuse resonance is determined by the transit time of the instability generated and nonlinearly maintained diffuse resonance wave from the remote short lived hot region back to the antenna. The model is consistent with the Alouette/ISIS observations, and clearly demonstrates the existence of nonlinear wave-particle interactions in the ionosphere.

[The analysis of negative life events, hopelessness and coping strategies among psychotic patients].

PubMed

Perczel Forintos, Dóra; Kiss, Zsófia

2008-01-01

Some theories explaining the background of suicidal attempts emphasise the role of depression, while others emphasise the role of hopelessness in the case of different psychological states, like psychosis. According to researches negative emotions, namely hopelessness predicts suicidal intentions more precisely than depression itself. In our study we measured the suicidal risk of our psychotic patients with hopelessness, depression and life event scales. Our results have implied that suicidal psychotic patient groups showed significantly more serious level of depression and hopelessness and had more negative life events than the non-suicidal group. Indeed, a sub-group could also be distinguished among suicidal psychotic patients in which the level of hopelessness predicts suicidal risk and not depression.

Anxiety/aggression--driven depression. A paradigm of functionalization and verticalization of psychiatric diagnosis.

PubMed

Van Praag, H M

2001-05-01

A new subtype of depression is proposed, named: anxiety/aggression-driven depression. The psychopathological, psychopharmacological and biochemical evidence on which this construct is based, is being discussed. Selective postsynaptic 5-HT1A agonists together with CRH and/or cortisol antagonists are hypothesized to be a specific biological treatment for this depression type, in conjunction with psychological interventions to raise the stressor-threshold and to increase coping skills. The development of this depression construct has been contingent on the introduction of two new diagnostic procedures, called functionalization and verticalization of psychiatric diagnosis. These procedures are explained and it is stressed that they are essential to psychiatric diagnosing, in order to put this process on a scientific footing.

Inbreeding depression in self-incompatible North-American Arabidopsis lyrata: disentangling genomic and S-locus-specific genetic load

PubMed Central

Stift, M; Hunter, B D; Shaw, B; Adam, A; Hoebe, P N; Mable, B K

2013-01-01

Newly formed selfing lineages may express recessive genetic load and suffer inbreeding depression. This can have a genome-wide genetic basis, or be due to loci linked to genes under balancing selection. Understanding the genetic architecture of inbreeding depression is important in the context of the maintenance of self-incompatibility and understanding the evolutionary dynamics of S-alleles. We addressed this using North-American subspecies of Arabidopsis lyrata. This species is normally self-incompatible and outcrossing, but some populations have undergone a transition to selfing. The goals of this study were to: (1) quantify the strength of inbreeding depression in North-American populations of A. lyrata; and (2) disentangle the relative contribution of S-linked genetic load compared with overall inbreeding depression. We enforced selfing in self-incompatible plants with known S-locus genotype by treatment with CO2, and compared the performance of selfed vs outcrossed progeny. We found significant inbreeding depression for germination rate (δ=0.33), survival rate to 4 weeks (δ=0.45) and early growth (δ=0.07), but not for flowering rate. For two out of four S-alleles in our design, we detected significant S-linked load reflected by an under-representation of S-locus homozygotes in selfed progeny. The presence or absence of S-linked load could not be explained by the dominance level of S-alleles. Instead, the random nature of the mutation process may explain differences in the recessive deleterious load among lineages. PMID:22892638

Drinking to Cope With Depressive Symptoms and Ruminative Thinking: A Multiple Mediation Model Among College Students.

PubMed

Bravo, Adrian J; Pearson, Matthew R; Henson, James M

2017-01-02

Understanding the potential psychosocial mechanisms that explain (i.e., mediate) the associations between depressive symptoms and alcohol-related problems can improve interventions targeting college students. The current research examined four distinct facets of rumination (e.g., problem-focused thoughts, counterfactual thinking, repetitive thoughts, and anticipatory thoughts) and drinking to cope motives as potential explanatory mechanisms by which depressive symptoms are associated with increased alcohol-related problems. Participants were undergraduate students from a large, southeastern university in the United States that consumed at least one drink per typical week in the previous month (n = 403). The majority of participants were female (n = 291; 72.2%), identified as being either White, non-Hispanic (n = 210; 52.1%), or African American (n = 110; 27.3%), and reported a mean age of 21.92 (SD = 5.75) years. Structural equation modeling was conducted examining the concurrent associations between depressive symptoms, rumination facets, drinking to cope motives, and alcohol-related problems (i.e., cross-sectional). There was one significant double-mediated association that suggested that increased depressive symptoms is associated with increased problem-focused thoughts, which is associated with higher drinking to cope motives and alcohol-related problems. Conclusions/Importance: Our results suggests that problem-focused thoughts at least partially explains the associations between depression and maladaptive coping (i.e., drinking to cope), which in turn is related to problematic drinking among college students. Limitations and future directions are discussed.

Machine learning approaches for integrating clinical and imaging features in late-life depression classification and response prediction.

PubMed

Patel, Meenal J; Andreescu, Carmen; Price, Julie C; Edelman, Kathryn L; Reynolds, Charles F; Aizenstein, Howard J

2015-10-01

Currently, depression diagnosis relies primarily on behavioral symptoms and signs, and treatment is guided by trial and error instead of evaluating associated underlying brain characteristics. Unlike past studies, we attempted to estimate accurate prediction models for late-life depression diagnosis and treatment response using multiple machine learning methods with inputs of multi-modal imaging and non-imaging whole brain and network-based features. Late-life depression patients (medicated post-recruitment) (n = 33) and older non-depressed individuals (n = 35) were recruited. Their demographics and cognitive ability scores were recorded, and brain characteristics were acquired using multi-modal magnetic resonance imaging pretreatment. Linear and nonlinear learning methods were tested for estimating accurate prediction models. A learning method called alternating decision trees estimated the most accurate prediction models for late-life depression diagnosis (87.27% accuracy) and treatment response (89.47% accuracy). The diagnosis model included measures of age, Mini-mental state examination score, and structural imaging (e.g. whole brain atrophy and global white mater hyperintensity burden). The treatment response model included measures of structural and functional connectivity. Combinations of multi-modal imaging and/or non-imaging measures may help better predict late-life depression diagnosis and treatment response. As a preliminary observation, we speculate that the results may also suggest that different underlying brain characteristics defined by multi-modal imaging measures-rather than region-based differences-are associated with depression versus depression recovery because to our knowledge this is the first depression study to accurately predict both using the same approach. These findings may help better understand late-life depression and identify preliminary steps toward personalized late-life depression treatment. Copyright © 2015 John Wiley & Sons, Ltd.

Multiple-mode nonlinear free and forced vibrations of beams using finite element method

NASA Technical Reports Server (NTRS)

Mei, Chuh; Decha-Umphai, Kamolphan

1987-01-01

Multiple-mode nonlinear free and forced vibration of a beam is analyzed by the finite element method. The geometric nonlinearity is investigated. Inplane displacement and inertia (IDI) are also considered in the formulation. Harmonic force matrix is derived and explained. Nonlinear free vibration can be simply treated as a special case of the general forced vibration by setting the harmonic force matrix equal to zero. The effect of the higher modes is more pronouced for the clamped supported beam than the simply supported one. Beams without IDI yield more effect of the higher modes than the one with IDI. The effects of IDI are to reduce nonlinearity. For beams with end supports restrained from axial movement (immovable cases), only the hardening type nonlinearity is observed. However, beams of small slenderness ratio (L/R = 20) with movable end supports, the softening type nonlinearity is found. The concentrated force case yields a more severe response than the uniformly distributed force case. Finite element results are in good agreement with the solution of simple elliptic response, harmonic balance method, and Runge-Kutte method and experiment.

Directional asymmetry of the nonlinear wave phenomena in a three-dimensional granular phononic crystal under gravity.

PubMed

Merkel, A; Tournat, V; Gusev, V

2014-08-01

We report the experimental observation of the gravity-induced asymmetry for the nonlinear transformation of acoustic waves in a noncohesive granular phononic crystal. Because of the gravity, the contact precompression increases with depth inducing space variations of not only the linear and nonlinear elastic moduli but also of the acoustic wave dissipation. We show experimentally and explain theoretically that, in contrast to symmetric propagation of linear waves, the amplitude of the nonlinearly self-demodulated wave depends on whether the propagation of the waves is in the direction of the gravity or in the opposite direction. Among the observed nonlinear processes, we report frequency mixing of the two transverse-rotational modes belonging to the optical band of vibrations and propagating with negative phase velocities, which results in the excitation of a longitudinal wave belonging to the acoustic band of vibrations and propagating with positive phase velocity. We show that the measurements of the gravity-induced asymmetry in the nonlinear acoustic phenomena can be used to compare the in-depth distributions of the contact nonlinearity and of acoustic absorption.

Challenges to traditional clinical definitions of depression in young black men.

PubMed

Perkins, Danielle E K

2014-01-01

Despite high rates of unemployment, incarceration, violence, and suicide experienced by young Black men in America, research conducted in inner-city environments consistently report nonsignificant levels of depression among Black men. The unique history of social exclusion, stereotyping, and discrimination experienced by Black men has significant implications for the accurate assessment of depression. A review of significant historical and current sociological, educational, and legal-justice circumstances that affect the mental health of young Black men is presented. Barriers and limitations to traditional depression assessment and measurement is discussed and followed by recommendations for advancing knowledge of depression in young Black men. Research and practice that seeks to explore and explain sociocultural variances in traditional definitions of depression among young Black men will improve mental health, mental health outreach, and social function in this population.

Raised by Depressed Parents: Is it an Environmental Risk?

PubMed Central

Natsuaki, Misaki N.; Shaw, Daniel S.; Neiderhiser, Jenae M.; Ganiban, M. Jody; Gordon, T. Harold; Reiss, David; Leve, Leslie D.

2014-01-01

The mechanisms explaining how parental depression compromises healthy child development are complex and multifaceted, with genetic and environmental pathways intertwined. Reexamination of whether and how maternal and paternal depression serve as environmental risk factors is important because such an investigation can be helpful to identify modifiable mechanisms that are accessible to interventions. We review studies that have employed designs that isolate the effects of the environment from genetic influences, including adoption studies and children of twins studies. Findings indicate that maternal depression is an environmental risk factor for the emotional, behavioral, and neurobiological development of children. Although more studies are needed, preliminary findings suggest that paternal depression appears to be a weaker environmental risk as compared to maternal depression, at least during infancy and toddlerhood. Implications for theory and future research are discussed. PMID:24817170

Pressure fluctuations and time scales in turbulent channel flow

NASA Astrophysics Data System (ADS)

Septham, Kamthon; Morrison, Jonathan; Diwan, Sourabh

2015-11-01

Pressure fluctuations in turbulent channel flow subjected to globally stabilising linear feedback control are investigated at Reτ = 400 . The passivity-based control is adopted and explained by the conservative characteristics of the nonlinear terms contributing to the Reynolds-Orr equation (Sharma et al. Phys. Fluids 2011). The linear control operates via vU' ; the maximum forcing is located at y+ ~ 20 , corresponding to the location of the maximum in the mean-square pressure gradient. The responses of the rapid (linear) and slow (nonlinear) pressure fluctuations to the linear control are investigated using the Green's function representations. It demonstrates that the linear control operates via the linear source terms of the Poisson equation for pressure fluctuations. Landahl's timescales of the minimal flow unit (MFU) in turbulent channel flow are examined at y+ = 20 . It shows that the timescales of MFU agree well with the theoretical values proposed by Landahl (1993). Therefore, the effectiveness of the linear control to attenuate wall turbulence is explained by Landahl's theory for timescales, in that the control proceeds via the shear interaction timescale which is significantly shorter than both the nonlinear and viscous timescales.

Coherent current-carrying filaments during nonlinear reconnecting ELMs and VDEs

NASA Astrophysics Data System (ADS)

Ebrahimi, Fatima

2017-10-01

We have examined plasmoid-mediated reconnection in a spherical tokamak using global nonlinear three-dimensional resistive MHD simulations with NIMROD. We have shown that physical current sheets/layers develop near the edge as a peeling component of ELMs or during vertical displacement events (associated with the scrape-off layer currents - halo currents), can become unstable to nonaxisymmetric 3-D current-sheet instabilities (peeling- or tearing-like) and nonlinearly form edge coherent current-carrying filaments. Time-evolving edge current sheets with reconnecting nature in NSTX and NSTX-U configurations are identified. In the case of peeling-like edge localized modes, the longstanding problem of quasiperiodic ELMs cycles is explained through the relaxation of edge current via direct numerical calculations of reconnecting emf terms. For the VDEs during disruption, we show that as the plasma is vertically displaced, edge halo current sheet becomes MHD unstable and forms coherent edge current filament structures, which would eventually bleed into the walls. Our model explains some essential asymmetric physics relevant to the experimental observations. Supported by DOE Grants DE-SC0010565, DE-AC02-09CH11466.

Psychosocial correlates, psychological distress, and quality of life in patients with medically unexplained symptoms: a primary care study in Karachi, Pakistan.

PubMed

Husain, Muhammad Ishrat; Chaudhry, Nasim; Morris, Julie; Zafar, Shehla Naeem; Jaffery, Farhat; Rahman, Raza; Duddu, Venu; Husain, Nusrat

2015-01-01

To examine the psychosocial correlates and association of psychological distress and quality of life (QOL) in patients with medically unexplained symptoms (MUS) compared to those with medically explained symptoms (MES) in a primary care setting in Karachi, Pakistan. A cross-sectional study of 472 patients attending GP clinics between March and August 2009 in Karachi. Participants completed questionnaires to assess demographic details, somatic symptoms, anxiety, depression, and QOL. The patients' GP recorded whether the presenting complaint was medically unexplained or medically explained. MUS subjects in our study were more educated, had better social support and fewer financial problems, were less depressed and had a better QOL than subjects who had medically explained symptoms (non-MUS). Both groups (MUS and non-MUS) were comparable in terms of anxiety and number of somatic symptoms, but non-MUS subjects were more depressed than the MUS group. In a regression analysis, the number of somatic symptoms and lower levels of anxiety predicted poorer QOL in this sample. Whether these symptoms were medically explained (or not) did not seem to contribute significantly to the QOL. Our findings confirm that even in the developing world, patients with MUS are common among primary care attendees. However, patients with MUS in urban Karachi, Pakistan may differ from Western MUS subjects in the role of stress, support, and anxiety in their presentation, and may be reflective of a conceptually different group of difficulties. © 2015, The Author(s).

A study in persons later after stroke of the relationships between social participation, environmental factors and depression.

PubMed

Zhang, Lifang; Sui, Minghong; Yan, Tiebin; You, Liming; Li, Kun; Gao, Yan

2017-03-01

To explore the impacts of social participation and the environment on depression among people with stroke. Cross-sectional survey. Structured interviews in the participants' homes. Community-dwelling persons with stroke in the rural areas of China ( N = 639). Not applicable. Depression (Hamilton Rating Scale for Depression-6), activity and social participation (Chinese version of the World Health Organization's Disability Assessment Schedule 2.0), environmental barriers (Craig Hospital Inventory of Environmental Factors), neurological function (Canadian Neurological Scale). A total of 42% of the variance in depression was explained by the environmental barriers, neurological function, activity, and social participation factors studied. Social participation, services/assistance, and attitudes/support were directly related to depression; their standardized regression coefficients were 0.530, 0.162, and 0.092, respectively ( p ⩽ 0.01). The physical environment, policies, and neurological function indirectly impacted depression. Depression influences social participation in turn, with a standardized regression coefficient of 0.29 ( p ⩽ 0.01). Depression and social participation are inversely related. The physical environment, services/assistance, attitudes/support, and policies all impact post-stroke depression.

An exponential decay model for mediation.

PubMed

Fritz, Matthew S

2014-10-01

Mediation analysis is often used to investigate mechanisms of change in prevention research. Results finding mediation are strengthened when longitudinal data are used because of the need for temporal precedence. Current longitudinal mediation models have focused mainly on linear change, but many variables in prevention change nonlinearly across time. The most common solution to nonlinearity is to add a quadratic term to the linear model, but this can lead to the use of the quadratic function to explain all nonlinearity, regardless of theory and the characteristics of the variables in the model. The current study describes the problems that arise when quadratic functions are used to describe all nonlinearity and how the use of nonlinear functions, such as exponential decay, address many of these problems. In addition, nonlinear models provide several advantages over polynomial models including usefulness of parameters, parsimony, and generalizability. The effects of using nonlinear functions for mediation analysis are then discussed and a nonlinear growth curve model for mediation is presented. An empirical example using data from a randomized intervention study is then provided to illustrate the estimation and interpretation of the model. Implications, limitations, and future directions are also discussed.

An Exponential Decay Model for Mediation

PubMed Central

Fritz, Matthew S.

2013-01-01

Mediation analysis is often used to investigate mechanisms of change in prevention research. Results finding mediation are strengthened when longitudinal data are used because of the need for temporal precedence. Current longitudinal mediation models have focused mainly on linear change, but many variables in prevention change nonlinearly across time. The most common solution to nonlinearity is to add a quadratic term to the linear model, but this can lead to the use of the quadratic function to explain all nonlinearity, regardless of theory and the characteristics of the variables in the model. The current study describes the problems that arise when quadratic functions are used to describe all nonlinearity and how the use of nonlinear functions, such as exponential decay, addresses many of these problems. In addition, nonlinear models provide several advantages over polynomial models including usefulness of parameters, parsimony, and generalizability. The effects of using nonlinear functions for mediation analysis are then discussed and a nonlinear growth curve model for mediation is presented. An empirical example using data from a randomized intervention study is then provided to illustrate the estimation and interpretation of the model. Implications, limitations, and future directions are also discussed. PMID:23625557

Wrinkling of Stretched Films: Shear Stress

NASA Technical Reports Server (NTRS)

Zak, M. A.

1982-01-01

Report presents theoretical investigation on nonlinear shearing characteristics of wrinkling films under applied shear stress. Report helps explain force/deflection characteristic of in-planeboom and solar-array blanket structural combinations.

Sloppy-model universality class and the Vandermonde matrix.

PubMed

Waterfall, Joshua J; Casey, Fergal P; Gutenkunst, Ryan N; Brown, Kevin S; Myers, Christopher R; Brouwer, Piet W; Elser, Veit; Sethna, James P

2006-10-13

In a variety of contexts, physicists study complex, nonlinear models with many unknown or tunable parameters to explain experimental data. We explain why such systems so often are sloppy: the system behavior depends only on a few "stiff" combinations of the parameters and is unchanged as other "sloppy" parameter combinations vary by orders of magnitude. We observe that the eigenvalue spectra for the sensitivity of sloppy models have a striking, characteristic form with a density of logarithms of eigenvalues which is roughly constant over a large range. We suggest that the common features of sloppy models indicate that they may belong to a common universality class. In particular, we motivate focusing on a Vandermonde ensemble of multiparameter nonlinear models and show in one limit that they exhibit the universal features of sloppy models.

Extracting Leading Nonlinear Modes of Changing Climate From Global SST Time Series

NASA Astrophysics Data System (ADS)

Mukhin, D.; Gavrilov, A.; Loskutov, E. M.; Feigin, A. M.; Kurths, J.

2017-12-01

Data-driven modeling of climate requires adequate principal variables extracted from observed high-dimensional data. For constructing such variables it is needed to find spatial-temporal patterns explaining a substantial part of the variability and comprising all dynamically related time series from the data. The difficulties of this task rise from the nonlinearity and non-stationarity of the climate dynamical system. The nonlinearity leads to insufficiency of linear methods of data decomposition for separating different processes entangled in the observed time series. On the other hand, various forcings, both anthropogenic and natural, make the dynamics non-stationary, and we should be able to describe the response of the system to such forcings in order to separate the modes explaining the internal variability. The method we present is aimed to overcome both these problems. The method is based on the Nonlinear Dynamical Mode (NDM) decomposition [1,2], but takes into account external forcing signals. An each mode depends on hidden, unknown a priori, time series which, together with external forcing time series, are mapped onto data space. Finding both the hidden signals and the mapping allows us to study the evolution of the modes' structure in changing external conditions and to compare the roles of the internal variability and forcing in the observed behavior. The method is used for extracting of the principal modes of SST variability on inter-annual and multidecadal time scales accounting the external forcings such as CO2, variations of the solar activity and volcanic activity. The structure of the revealed teleconnection patterns as well as their forecast under different CO2 emission scenarios are discussed.[1] Mukhin, D., Gavrilov, A., Feigin, A., Loskutov, E., & Kurths, J. (2015). Principal nonlinear dynamical modes of climate variability. Scientific Reports, 5, 15510. [2] Gavrilov, A., Mukhin, D., Loskutov, E., Volodin, E., Feigin, A., & Kurths, J. (2016). Method for reconstructing nonlinear modes with adaptive structure from multidimensional data. Chaos: An Interdisciplinary Journal of Nonlinear Science, 26(12), 123101.

Weight loss after head and neck cancer: A dynamic relationship with depressive symptoms

PubMed Central

Van Liew, Julia R.; Brock, Rebecca L.; Christensen, Alan J.; Karnell, Lucy Hynds; Pagedar, Nitin A.; Funk, Gerry F.

2018-01-01

Background Weight loss (WL) and depressive symptoms are critical head and neck cancer (HNC) outcomes, yet their relation over the illness course is unclear. Methods Associations between self-reported depressive symptoms and objective WL across the year following HNC diagnosis were examined using growth curve modeling techniques (N=564). Results A reciprocal covariation pattern emerged—changes in depressive symptoms over time were associated with same-month changes in WL, t (1148) = 2.05, p = .041, and changes in WL were associated with same-month changes in depressive symptoms, t (556) = 2.43, p = .015. To the extent that depressive symptoms increased, patients lost incrementally more weight than was lost due to the passage of time, and vice versa. Results also suggested that pain and eating-related quality of life might explain the reciprocal association between depressive symptoms and WL. Conclusions In HNC, a transactional interplay between depressive symptoms and WL unfolds over time. PMID:27704695

Integrated management of major depression for people with cancer.

PubMed

Walker, Jane; Sharpe, Michael

2014-12-01

Major depression is an important complication of cancer. However, it is frequently inadequately treated. There are challenges both in identifying which cancer patients are depressed, and in ensuring that these patients receive effective treatment for their depression. Integration of depression management into cancer care has been advocated as a way to address these challenges. Such integrated approaches must include both the systematic identification of cases and the delivery of treatment. We describe here a system of depression care that includes both a screening programme to identify patients with depression and a linked treatment programme, based on the collaborative care model, called 'Depression Care for People with Cancer' (DCPC). The system of care was designed to be fully integrated with specialist cancer services and has been robustly evaluated in randomized trials. We describe how the system operates and explain why it is designed as it is. We also summarize the evidence for its effectiveness and cost-effectiveness and discuss its implementation in routine clinical practice.

Natural stiffening increases flaw tolerance of biological fibers

NASA Astrophysics Data System (ADS)

Giesa, Tristan; Pugno, Nicola M.; Buehler, Markus J.

2012-10-01

Many fibers in biomaterials such as tendon, elastin, or silk feature a nonlinear stiffening behavior of the stress-strain relationship, where the rigidity of the material increases severely as the material is being stretched. Here we show that such nonlinear stiffening is beneficial for a fiber's ability to withstand cracks, leading to a flaw tolerant state in which stress concentrations around cracks are diminished. Our findings, established by molecular mechanics and the derivation of a theoretical scaling law, explain experimentally observed fiber sizes in a range of biomaterials and point to the importance of nonlinear stiffening to enhance their fracture properties. Our study suggests that nonlinear stiffening provides a mechanism by which nanoscale mechanical properties can be scaled up, providing a means towards bioinspired fibrous material and structural design.

An Underlying Common Factor, Influenced by Genetics and Unique Environment, Explains the Covariation Between Major Depressive Disorder, Generalized Anxiety Disorder, and Burnout: A Swedish Twin Study.

PubMed

Mather, Lisa; Blom, Victoria; Bergström, Gunnar; Svedberg, Pia

2016-12-01

Depression and anxiety are highly comorbid due to shared genetic risk factors, but less is known about whether burnout shares these risk factors. We aimed to examine whether the covariation between major depressive disorder (MDD), generalized anxiety disorder (GAD), and burnout is explained by common genetic and/or environmental factors. This cross-sectional study included 25,378 Swedish twins responding to a survey in 2005-2006. Structural equation models were used to analyze whether the trait variances and covariances were due to additive genetics, non-additive genetics, shared environment, and unique environment. Univariate analyses tested sex limitation models and multivariate analysis tested Cholesky, independent pathway, and common pathway models. The phenotypic correlations were 0.71 (0.69-0.74) between MDD and GAD, 0.58 (0.56-0.60) between MDD and burnout, and 0.53 (0.50-0.56) between GAD and burnout. Heritabilities were 45% for MDD, 49% for GAD, and 38% for burnout; no statistically significant sex differences were found. A common pathway model was chosen as the final model. The common factor was influenced by genetics (58%) and unique environment (42%), and explained 77% of the variation in MDD, 69% in GAD, and 44% in burnout. GAD and burnout had additive genetic factors unique to the phenotypes (11% each), while MDD did not. Unique environment explained 23% of the variability in MDD, 20% in GAD, and 45% in burnout. In conclusion, the covariation was explained by an underlying common factor, largely influenced by genetics. Burnout was to a large degree influenced by unique environmental factors not shared with MDD and GAD.

Nonlinear cascades in two-dimensional turbulent magnetoconvection.

PubMed

Skandera, Dan; Müller, Wolf-Christian

2009-06-05

The dynamics of spectral transport in two-dimensional turbulent convection of electrically conducting fluids is studied by means of direct numerical simulations in the frame of the magnetohydrodynamic Boussinesq approximation. The system performs quasioscillations between two different regimes of small-scale turbulence: one dominated by nonlinear magnetohydrodynamic interactions; the other governed by buoyancy forces. The self-excited change of turbulent states is reported here for the first time. The process is controlled by the ideal invariant cross helicity, H;{C}=integral_{S}dSv.b. The observations are explained by the interplay of convective driving with the nonlinear spectral transfer of total magnetohydrodynamic energy and cross helicity.

The Great Depression and the Arts. A Unit of Study for Grades 8-12.

ERIC Educational Resources Information Center

Gabrick, Robert; Markham, Barbara; Curtis, James

This teaching unit is based on primary sources, taken from government documents, artifacts, magazines, newspapers, films, and literature from the U.S. historical period under study, which in this case, is the Great Depression of the 1930s and Franklin D. Roosevelt's response to it--the New Deal. The unit explains that the New Deal established the…

The Role of Perceived Control in Explaining Depressive Symptoms Associated with Driving Cessation in a Longitudinal Study

ERIC Educational Resources Information Center

Windsor, Timothy D.; Anstey, Kaarin J.; Butterworth, Peter; Luszcz, Mary A.; Andrews, Gary R.

2007-01-01

Purpose: The purpose of this article was to investigate the role of control beliefs in mediating the relationship between driving cessation and change in depressive symptoms in a population-based sample of older adults. Design and Methods: We report results from a prospective, community-based cohort study that included two waves of data collected…

HPA axis response to social stress is attenuated in schizophrenia but normal in depression: evidence from a meta-analysis of existing studies.

PubMed

Ciufolini, Simone; Dazzan, Paola; Kempton, Matthew J; Pariante, Carmine; Mondelli, Valeria

2014-11-01

We conducted a meta-analysis to investigate the HPA axis response to social stress in studies that used the Trier Social Stress Test (TSST), or comparable distressing paradigms, in individuals with either depression or schizophrenia. Sample size-adjusted effect sizes (Hedge's g statistic) were calculated to estimate the HPA axis stress response to social stress. We used a meta-regression model to take into account the moderating effect of the baseline cortisol level. Participants with depression show an activation pattern to social stress similar to that of healthy controls. Despite a normal cortisol production rate, individuals with schizophrenia have lower cortisol levels than controls both in anticipation and after exposure to social stress. Participants with depression and higher cortisol levels before the task have an increased cortisol production and reached higher cortisol levels during the task. This may be explained by the presence of an impaired negative feedback. The activation pattern present in schizophrenia may explain the reduced ability to appropriately contextualize past experiences shown by individuals with psychosis in social stressful situation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Adaptive enhancement for nonuniform illumination images via nonlinear mapping

NASA Astrophysics Data System (ADS)

Wang, Yanfang; Huang, Qian; Hu, Jing

2017-09-01

Nonuniform illumination images suffer from degenerated details because of underexposure, overexposure, or a combination of both. To improve the visual quality of color images, underexposure regions should be lightened, whereas overexposure areas need to be dimmed properly. However, discriminating between underexposure and overexposure is troublesome. Compared with traditional methods that produce a fixed demarcation value throughout an image, the proposed demarcation changes as local luminance varies, thus is suitable for manipulating complicated illumination. Based on this locally adaptive demarcation, a nonlinear modification is applied to image luminance. Further, with the modified luminance, we propose a nonlinear process to reconstruct a luminance-enhanced color image. For every pixel, this nonlinear process takes the luminance change and the original chromaticity into account, thus trying to avoid exaggerated colors at dark areas and depressed colors at highly bright regions. Finally, to improve image contrast, a local and image-dependent exponential technique is designed and applied to the RGB channels of the obtained color image. Experimental results demonstrate that our method produces good contrast and vivid color for both nonuniform illumination images and images with normal illumination.

Can Neurochemical Changes of Mood Disorders Explain the Increase Risk of Epilepsy or its Worse Seizure Control?

PubMed

Kanner, Andres M

2017-07-01

The existence of a bidirectional relation between mood disorders and epilepsy has been suggested by six population-based studies. Furthermore, three studies have associated a higher risk of treatment-resistant epilepsy with a history of depression preceding the onset of epilepsy. Common pathogenic mechanisms operant in depression and epilepsy may provide a possible explanation of these observations. This article reviews some of the leading pathogenic mechanisms of depression with respect to potential proconvulsant properties that may provide explanations for these phenomena.

On the unsteady gravity-capillary wave pattern found behind a slow moving localized pressure distribution

NASA Astrophysics Data System (ADS)

Masnadi, N.; Duncan, J. H.

2013-11-01

The non-linear response of a water surface to a slow-moving pressure distribution is studied experimentally using a vertically oriented carriage-mounted air-jet tube that is set to translate over the water surface in a long tank. The free surface deformation pattern is measured with a full-field refraction-based method that utilizes a vertically oriented digital movie camera (under the tank) and a random dot pattern (above the water surface). At towing speeds just below the minimum phase speed of gravity-capillary waves (cmin ~ 23 cm/s), an unsteady V-shaped pattern is formed behind the pressure source. Localized depressions are generated near the source and propagate in pairs along the two arms of the V-shaped pattern. These depressions are eventually shed from the tips of the pattern at a frequency of about 1 Hz. It is found that the shape and phase speeds of the first depressions shed in each run are quantitatively similar to the freely-propagating gravity-capillary lumps from potential flow calculations. In the experiments, the amplitudes of the depressions decrease by approximately 60 percent while travelling 12 wavelengths. The depressions shed later in each run behave in a less consistent manner, probably due to their interaction with neighboring depressions.

Detection of Clinical Depression in Adolescents’ Speech During Family Interactions

PubMed Central

Low, Lu-Shih Alex; Maddage, Namunu C.; Lech, Margaret; Sheeber, Lisa B.; Allen, Nicholas B.

2013-01-01

The properties of acoustic speech have previously been investigated as possible cues for depression in adults. However, these studies were restricted to small populations of patients and the speech recordings were made during patients’ clinical interviews or fixed-text reading sessions. Symptoms of depression often first appear during adolescence at a time when the voice is changing, in both males and females, suggesting that specific studies of these phenomena in adolescent populations are warranted. This study investigated acoustic correlates of depression in a large sample of 139 adolescents (68 clinically depressed and 71 controls). Speech recordings were made during naturalistic interactions between adolescents and their parents. Prosodic, cepstral, spectral, and glottal features, as well as features derived from the Teager energy operator (TEO), were tested within a binary classification framework. Strong gender differences in classification accuracy were observed. The TEO-based features clearly outperformed all other features and feature combinations, providing classification accuracy ranging between 81%–87% for males and 72%–79% for females. Close, but slightly less accurate, results were obtained by combining glottal features with prosodic and spectral features (67%–69% for males and 70%–75% for females). These findings indicate the importance of nonlinear mechanisms associated with the glottal flow formation as cues for clinical depression. PMID:21075715

Maternal distress explains the relationship of young African American mothers' violence exposure with their preschoolers' behavior.

PubMed

Mitchell, Stephanie J; Lewin, Amy; Rasmussen, Andrew; Horn, Ivor B; Joseph, Jill G

2011-02-01

Adolescent mothers and their children are particularly susceptible to witnessing or directly experiencing violence. Such violence exposure predicts maternal distress, parenting, and child behavior problems. The current study examined how mothers' depressive symptoms, aggression, harsh disciplinary practices, and home environment independently explain the association between mothers' violence exposure and children's externalizing and internalizing behavior, controlling for their children's violence exposure. Data were collected from 230 African American mothers living in Washington, DC who gave birth as adolescents and whose children were 3 to 5 years old. Path analysis revealed that the effect of mothers' experienced violence on children's externalizing and internalizing behavior was mediated by mothers' depressive symptoms and aggression. However, neither harsh discipline nor stimulation in the home environment acted as significant mediators, and there were no direct or indirect effects of mothers' witnessed violence on child behavior. This study builds on previous work by identifying an association between maternal violence exposure and children's behavior, independent of children's own violence exposure that is explained by mothers' increased distress but not their parenting. These findings suggest that a potential means of preventing behavior problems in minority children born to adolescent mothers is to identify mothers who have been directly exposed to violence and treat their depressive symptoms and aggressive behaviors.

Disclosing HIV serostatus to family members: Effects on psychological and physiological health in minority women living with HIV.

PubMed

Fekete, Erin M; Antoni, Michael H; Durán, Ron; Stoelb, Brenda L; Kumar, Mahendra; Schneiderman, Neil

2009-01-01

Directly disclosing a positive HIV serostatus to family members can have psychological and physiological health benefits. Perceptions that one is in a supportive family environment may enhance these benefits. We examined a mediated moderation model in which we expected interactions between serostatus disclosure to family members and HIV-specific family support to be associated with women's perceived stress, which in turn would explain depressive symptoms and 24-h urinary cortisol in women living with HIV (WLWH). Low-income ethnic minority WLWH (n = 82) reported the percentage of family members they had directly disclosed their serostatus to, perceptions of HIV-related support from family members, perceived stress, and depressive symptoms. Cortisol was measured via 24-h urinary collection. Disclosure to spouses and children coupled with high levels of family support was associated with higher levels of depressive symptoms in women. For disclosure to spouses, this relationship was explained by higher perceived stress. Direct disclosure to mothers in tandem with high support was associated with lower cortisol, and this relationship was explained through higher levels of perceived stress. The effects of serostatus disclosure on perceived stress and health in WLWH may depend, in part, on women's family environment and to whom they disclose to within that environment.

Leader dark traits, workplace bullying, and employee depression: Exploring mediation and the role of the dark core.

PubMed

Tokarev, Alexander; Phillips, Abigail R; Hughes, David J; Irwing, Paul

2017-10-01

A growing body of empirical evidence now supports a negative association between dark traits in leaders and the psychological health of employees. To date, such investigations have mostly focused on psychopathy, nonspecific measures of psychological wellbeing, and have not considered the mechanisms through which these relationships might operate. In the current study (N = 508), we utilized other-ratings of personality (employees rated leaders' personality), psychometrically robust measures, and sophisticated modeling techniques, to examine whether the effects of leaders' levels of narcissism and psychopathy on employee depression are mediated by workplace bullying. Structural equation models provided clear evidence to suggest that employee perceptions of both leader narcissism and psychopathy are associated with increased workplace bullying (25.8% and 41.0% variance explained, respectively) and that workplace bullying fully mediates the effect of leader narcissism and psychopathy on employee depression (21.5% and 20.8% variance explained, respectively). However, when psychopathy and narcissism were modeled concurrently, narcissism did not explain any variance in bullying, suggesting that it is the overlap between psychopathy and narcissism, namely, the "dark core," which primarily accounts for the observed effects. We examined this assertion empirically and explored the unique effects of the subfactors of psychopathy. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

The relationship of social function to depressive and negative symptoms in individuals at clinical high risk for psychosis.

PubMed

Corcoran, C M; Kimhy, D; Parrilla-Escobar, M A; Cressman, V L; Stanford, A D; Thompson, J; David, S Ben; Crumbley, A; Schobel, S; Moore, H; Malaspina, D

2011-02-01

Social dysfunction is a hallmark symptom of schizophrenia which commonly precedes the onset of psychosis. It is unclear if social symptoms in clinical high-risk patients reflect depressive symptoms or are a manifestation of negative symptoms. We compared social function scores on the Social Adjustment Scale-Self Report between 56 young people (aged 13-27 years) at clinical high risk for psychosis and 22 healthy controls. The cases were also assessed for depressive and 'prodromal' symptoms (subthreshold positive, negative, disorganized and general symptoms). Poor social function was related to both depressive and negative symptoms, as well as to disorganized and general symptoms. The symptoms were highly intercorrelated but linear regression analysis demonstrated that poor social function was primarily explained by negative symptoms within this cohort, particularly in ethnic minority patients. Although this study demonstrated a relationship between social dysfunction and depressive symptoms in clinical high-risk cases, this association was primarily explained by the relationship of each of these to negative symptoms. In individuals at heightened risk for psychosis, affective changes may be related to a progressive decrease in social interaction and loss of reinforcement of social behaviors. These findings have relevance for potential treatment strategies for social dysfunction in schizophrenia and its risk states and predict that antidepressant drugs, cognitive behavioral therapy and/or social skills training may be effective.

Avoidance as an obstacle to preventing depression among urban women at high risk for violent trauma.

PubMed

Silverstein, Michael; Kistin, Caroline; Bair-Merritt, Megan; Wiltsey-Stirman, Shannon; Feinberg, Emily; Diaz-Linhart, Yaminette; Sandler, Jenna; Chen, Ning; Cabral, Howard

2016-02-01

The impact of depression interventions is often attenuated in women who have experienced trauma. We explored whether psychological avoidance could explain this phenomenon. We synthesized two pilot randomized trials of problem-solving education (PSE) among a total of 93 urban mothers. Outcomes included depressive symptoms and perceived stress. Mothers with avoidant coping styles experienced an average 1.25 episodes of moderately severe depressive symptoms over 3 months of follow-up, compared to 0.40 episodes among those with non-avoidant coping (adjusted incident rate ratio [aIRR] 2.18; 95 % CI 1.06, 4.48). PSE tended to perform better among mothers with non-avoidant coping. Among mothers with non-avoidant coping, PSE mothers experienced an average 0.24 episodes, compared to 0.58 episodes among non-avoidant controls (aIRR 0.27; 95 % CI 0.05, 1.34). Among mothers with avoidant coping, PSE mothers experienced an average 1.26 episodes, compared to 1.20 episodes among avoidant controls (aIRR 0.76; 95 % CI 0.44, 1.33). This trend toward differential impact persisted when avoidance was measured as a problem-solving style and among traumatized mothers with and without avoidant PTSD symptoms. Further research is warranted to explore the hypothesis that psychological avoidance could explain why certain depression treatment and prevention strategies break down in the presence of trauma.

Crisis of Meaning Predicts Suicidality in Youth Independently of Depression.

PubMed

Schnell, Tatjana; Gerstner, Rebekka; Krampe, Henning

2018-02-23

At times, the question for meaning comes to nothing and a crisis of meaning ensues. This state is very painful, but difficult to account. Both those who suffer from it and care professionals find themselves at a loss for words. This study introduces an operationalization of a crisis of meaning. It aims to distinguish the concept from depression, and to investigate whether a crisis of meaning can explain suicidality beyond the known protective and risk factors self-esteem, family functioning, life-event load, and depression. Final-year school pupils in Ecuador (N = 300) completed questionnaires assessing the above variables. Data were analyzed using chi-square, hierarchic multiple regression, serial mediation, and moderator analyses. Crisis of meaning was distinguished from depression. It explained a significant amount of variance in suicidality beyond the mentioned protective and risk factors. For males, crisis of meaning was the only significant risk factor, and the strongest predictor overall. The acute risk factors depression and crisis of meaning mediated the effects of the baseline factors self-esteem, family functioning, and life-event load on suicidality. The study was cross-sectional; assessed factors predicted variance in suicidal thoughts, plans, and past suicide attempts, while their relevance cannot be generalized to actual future suicide attempts. A crisis of meaning is an important factor to take into account in further research on the prevention and treatment of people at risk of suicide.

Escitalopram plasma levels and antidepressant response.

PubMed

Florio, Vincenzo; Porcelli, Stefano; Saria, Alois; Serretti, Alessandro; Conca, Andreas

2017-09-01

Major Depression Disorder (MDD) has a highly variable treatment response due to the large inter-individual variation in the pharmacokinetics and pharmacodynamics of drug treatments. In detail the correlation between plasma level and efficacy has been much debated. Among first-line drugs for MDD, one of the most used is escitalopram. In the present study we investigated the association between serum concentration of escitalopram (SCE) and antidepressant response (AR). 70 MDD patients treated with escitalopram monotherapy were recruited and followed for three months. Hamilton Depression Rating Scale - 21 (HAMD-21) was administrated at baseline, month 1, and month 3 to assess AR. SCE was measured at steady state. Linear regression analysis and nonlinear least-squares regression were used to estimate association between SCE and AR. We found an association between SCE and AR both at month 1 (p<0.001) and month 3 (p=0.0003), which persists also excluding 3 patients with SCE equal to 0. Interestingly, by excluding patients with SCE < 20ng/mL, i.e. with a SCE lower than the putative therapeutic threshold, these associations disappeared. The curvilinear function AR = a + (SCE-SCE 2 ) explained a higher proportion of variance compared to the linear other models (p<0.001). Our results suggest that for escitalopram the association between SCE and AR likely follows a nearly-asymptotic function, with poor AR at sub-therapeutic SCE and stable AR response at therapeutic SCE. Thus, when a patient reaches the therapeutic SCE range, further increase of escitalopram dosage seems to be useless, although further studies are needed to confirm our findings. Copyright © 2017 Elsevier B.V. and ECNP. All rights reserved.

Assessing the presence of shared genetic architecture between Alzheimer's disease and major depressive disorder using genome-wide association data

PubMed Central

Gibson, J; Russ, T C; Adams, M J; Clarke, T-K; Howard, D M; Hall, L S; Fernandez-Pujals, A M; Wigmore, E M; Hayward, C; Davies, G; Murray, A D; Smith, B H; Porteous, D J; Deary, I J; McIntosh, A M

2017-01-01

Major depressive disorder (MDD) and Alzheimer's disease (AD) are both common in older age and frequently co-occur. Numerous phenotypic studies based on clinical diagnoses suggest that a history of depression increases risk of subsequent AD, although the basis of this relationship is uncertain. Both illnesses are polygenic, and shared genetic risk factors could explain some of the observed association. We used genotype data to test whether MDD and AD have an overlapping polygenic architecture in two large population-based cohorts, Generation Scotland's Scottish Family Health Study (GS:SFHS; N=19 889) and UK Biobank (N=25 118), and whether age of depression onset influences any relationship. Using two complementary techniques, we found no evidence that the disorders are influenced by common genetic variants. Using linkage disequilibrium score regression with genome-wide association study (GWAS) summary statistics from the International Genomics of Alzheimer's Project, we report no significant genetic correlation between AD and MDD (rG=−0.103, P=0.59). Polygenic risk scores (PRS) generated using summary data from International Genomics of Alzheimer's Project (IGAP) and the Psychiatric Genomics Consortium were used to assess potential pleiotropy between the disorders. PRS for MDD were nominally associated with participant-recalled AD family history in GS:SFHS, although this association did not survive multiple comparison testing. AD PRS were not associated with depression status or late-onset depression, and a survival analysis showed no association between age of depression onset and genetic risk for AD. This study found no evidence to support a common polygenic structure for AD and MDD, suggesting that the comorbidity of these disorders is not explained by common genetic variants. PMID:28418403

Disparities in Depressive Distress by Sexual Orientation in Emerging Adults: The Roles of Attachment and Stress Paradigms

PubMed Central

Rosario, Margaret; Reisner, Sari L.; Corliss, Heather L.; Wypij, David; Frazier, A. Lindsay; Austin, S. Bryn

2013-01-01

Lesbian, gay, and bisexual youth have elevated rates of depression compared to heterosexuals. We proposed and examined a theoretical model to understand whether attachment and stress paradigms explain disparities in depressive distress by sexual orientation, using the longitudinal Growing Up Today Study (GUTS) and Nurses’ Health Study II (NHSII). GUTS participants eligible for this analysis reported sexual orientation, childhood gender nonconforming behaviors (GNBs), attachment to mother (all in 2005), and depressive symptoms (in 2007). Mothers of the GUTS participants who are the NHSII participants reported attitudes toward homosexuality (in 2004) and maternal affection (in 2006). The sample had 6,122 participants. Of GUTS youth (M = 20.6 years old in 2005; 64.4% female), 1.7% were lesbian/gay (LG), 1.7% bisexual (BI), 10.0% mostly heterosexual (MH), and 86.7% completely heterosexual (CH). After adjusting for demographic characteristics and sibling clustering, LGs, BIs, and MHs reported more depressive distress than CHs. This relation was partially mediated (i.e., explained) for LGs, BIs, and MHs relative to CHs by less secure attachment. A conditional relation (i.e., interaction) indicated that BIs reported more distress than CHs as GNBs increased for BIs; no comparable relation was found for LGs vs. CHs. Sibling comparisons found that sexual minorities (LGs, BIs, and MHs) reported more depressive distress, less secure attachment, and more childhood GNBs than CH siblings; the mothers reported less affection for their sexual-minority than CH offspring. The findings suggest that attachment and childhood gender nonconformity differentially pattern depressive distress by sexual orientation. Attachment and related experiences are more problematic for sexual minorities than for their CH siblings. PMID:23780518

Disparities in depressive distress by sexual orientation in emerging adults: the roles of attachment and stress paradigms.

PubMed

Rosario, Margaret; Reisner, Sari L; Corliss, Heather L; Wypij, David; Frazier, A Lindsay; Austin, S Bryn

2014-07-01

Lesbian, gay, and bisexual (BI) youth have elevated rates of depression compared to heterosexuals. We proposed and examined a theoretical model to understand whether attachment and stress paradigms explain disparities in depressive distress by sexual orientation, using the longitudinal Growing Up Today Study (GUTS) and Nurses' Health Study II (NHSII). GUTS participants eligible for this analysis reported sexual orientation, childhood gender nonconforming behaviors (GNBs), attachment to mother (all in 2005), and depressive symptoms (in 2007). Mothers of the GUTS participants who are the NHSII participants reported attitudes toward homosexuality (in 2004) and maternal affection (in 2006). The sample had 6,122 participants. Of GUTS youth (M = 20.6 years old in 2005; 64.4 % female), 1.7 % were lesbian/gay (LG), 1.7 % bisexual (BI), 10.0 % mostly heterosexual (MH), and 86.7 % completely heterosexual (CH). After adjusting for demographic characteristics and sibling clustering, LGs, BIs, and MHs reported more depressive distress than CHs. This relation was partially mediated (i.e., explained) for LGs, BIs, and MHs relative to CHs by less secure attachment. A conditional relation (i.e., interaction) indicated that BIs reported more distress than CHs as GNBs increased for BIs; no comparable relation was found for LGs versus CHs. Sibling comparisons found that sexual minorities (LGs, BIs, and MHs) reported more depressive distress, less secure attachment, and more childhood GNBs than CH siblings; the mothers reported less affection for their sexual-minority than CH offspring. The findings suggest that attachment and childhood gender nonconformity differentially pattern depressive distress by sexual orientation. Attachment and related experiences are more problematic for sexual minorities than for their CH siblings.

The Chinese medicine construct "stagnation" in mind-body connection mediates the effects of mindfulness training on depression and anxiety.

PubMed

Lo, Herman H M; Ng, Siu Man; Chan, Cecilia L W; Lam, K F; Lau, Bobo H P

2013-08-01

Previous studies have identified different, but highly correlated variables explaining the effects of mindfulness training. Many of them are limited by tautological explanation. Under the framework of the mind-body connection, mindfulness training cultivates body awareness and promotes self-management of illness. Stagnation, a concept from Chinese medicine, may help explain the mechanism of change in mindfulness training. Individuals with depressive and anxiety symptoms (n=82) were randomized to either a Compassion-Mindfulness Therapy (C-MT) program or a waitlist control condition. The effect of stagnation as a mediator was investigated for dependent variables including depression, anxiety, and other physical and mental health variables. Depression, anxiety, stagnation, physical distress, daily functioning, positive affect, negative affect. Compared with the participants in the control group, those who completed C-MT demonstrated significant decreases in depression, F(1, 78)=15.67, p<.001, anxiety, F(1, 78)=7.72, p<.001, stagnation, F(1, 78)=4.96, p<.001, and other body-mind-spirit well-being measures. After entering the change in stagnation as the mediator, the effect of treatment reduced: depression (.35-.22), anxiety (.33-.05), and same patterns in other three secondary measures. The Sobel test was administered and significant reductions between group and depression (z=2.18, p=.029), anxiety (z=2.21, p=.027), and three secondary other measures (p<.05) were indicated. The study provides initial support for the role of stagnation in mediating changes in mindfulness training. It adds evidence to body-mind nondualism and offers new possibilities in studying treatment process and change mechanism. Copyright © 2013 Elsevier Ltd. All rights reserved.

Gender, position of authority, and the risk of depression and post-traumatic stress disorder among a national sample of U.S. Reserve Component Personnel

PubMed Central

Cohen, Gregory H.; Sampson, Laura A.; Fink, David S.; Wang, Jing; Russell, Dale; Gifford, Robert; Fullerton, Carol; Ursano, Robert; Galea, Sandro

2016-01-01

BACKGROUND Recent United States military operations in Iraq and Afghanistan have seen dramatic increases in the proportion of women serving, and the breadth of their occupational roles. General population studies suggest that women, compared to men, and persons with lower, as compared to higher, social position may be at greater risk of post-traumatic stress disorder (PTSD) and depression. However, these relations remain unclear in military populations. Accordingly, we aimed to estimate the effects of (1) gender, (2) military authority (i.e., rank) and (3) the interaction of gender and military authority upon: (a) risk of most-recent-deployment-related PTSD, and (b) risk of depression since most-recent-deployment. METHODS Using a nationally representative sample of 1024 previously deployed Reserve Component personnel surveyed in 2010, we constructed multivariable logistic regression models to estimate effects of interest. RESULTS Weighted multivariable logistic regression models demonstrated no statistically significant associations between gender or authority, and either PTSD or depression. Interaction models demonstrated multiplicative statistical interaction between gender and authority for PTSD (beta= −2.37;p=0.01), and depression (beta=-1.21; p=0.057). Predicted probabilities of PTSD and depression, respectively, were lowest in male officers (0.06, 0.09), followed by male enlisted (0.07, 0.14), female enlisted (0.07, 0.15), and female officers (0.30, 0.25). CONCLUSIONS Female officers in the Reserve Component may be at greatest risk for PTSD and depression following deployment, relative to their male and enlisted counterparts, and this relation is not explained by deployment trauma exposure. Future studies may fruitfully examine whether social support, family responsibilities peri-deployment, or contradictory class status may explain these findings. PMID:26899583

Assessing the presence of shared genetic architecture between Alzheimer's disease and major depressive disorder using genome-wide association data.

PubMed

Gibson, J; Russ, T C; Adams, M J; Clarke, T-K; Howard, D M; Hall, L S; Fernandez-Pujals, A M; Wigmore, E M; Hayward, C; Davies, G; Murray, A D; Smith, B H; Porteous, D J; Deary, I J; McIntosh, A M

2017-04-18

Major depressive disorder (MDD) and Alzheimer's disease (AD) are both common in older age and frequently co-occur. Numerous phenotypic studies based on clinical diagnoses suggest that a history of depression increases risk of subsequent AD, although the basis of this relationship is uncertain. Both illnesses are polygenic, and shared genetic risk factors could explain some of the observed association. We used genotype data to test whether MDD and AD have an overlapping polygenic architecture in two large population-based cohorts, Generation Scotland's Scottish Family Health Study (GS:SFHS; N=19 889) and UK Biobank (N=25 118), and whether age of depression onset influences any relationship. Using two complementary techniques, we found no evidence that the disorders are influenced by common genetic variants. Using linkage disequilibrium score regression with genome-wide association study (GWAS) summary statistics from the International Genomics of Alzheimer's Project, we report no significant genetic correlation between AD and MDD (r G =-0.103, P=0.59). Polygenic risk scores (PRS) generated using summary data from International Genomics of Alzheimer's Project (IGAP) and the Psychiatric Genomics Consortium were used to assess potential pleiotropy between the disorders. PRS for MDD were nominally associated with participant-recalled AD family history in GS:SFHS, although this association did not survive multiple comparison testing. AD PRS were not associated with depression status or late-onset depression, and a survival analysis showed no association between age of depression onset and genetic risk for AD. This study found no evidence to support a common polygenic structure for AD and MDD, suggesting that the comorbidity of these disorders is not explained by common genetic variants.

Frequency Preference Response to Oscillatory Inputs in Two-dimensional Neural Models: A Geometric Approach to Subthreshold Amplitude and Phase Resonance.

PubMed

Rotstein, Horacio G

2014-01-01

We investigate the dynamic mechanisms of generation of subthreshold and phase resonance in two-dimensional linear and linearized biophysical (conductance-based) models, and we extend our analysis to account for the effect of simple, but not necessarily weak, types of nonlinearities. Subthreshold resonance refers to the ability of neurons to exhibit a peak in their voltage amplitude response to oscillatory input currents at a preferred non-zero (resonant) frequency. Phase-resonance refers to the ability of neurons to exhibit a zero-phase (or zero-phase-shift) response to oscillatory input currents at a non-zero (phase-resonant) frequency. We adapt the classical phase-plane analysis approach to account for the dynamic effects of oscillatory inputs and develop a tool, the envelope-plane diagrams, that captures the role that conductances and time scales play in amplifying the voltage response at the resonant frequency band as compared to smaller and larger frequencies. We use envelope-plane diagrams in our analysis. We explain why the resonance phenomena do not necessarily arise from the presence of imaginary eigenvalues at rest, but rather they emerge from the interplay of the intrinsic and input time scales. We further explain why an increase in the time-scale separation causes an amplification of the voltage response in addition to shifting the resonant and phase-resonant frequencies. This is of fundamental importance for neural models since neurons typically exhibit a strong separation of time scales. We extend this approach to explain the effects of nonlinearities on both resonance and phase-resonance. We demonstrate that nonlinearities in the voltage equation cause amplifications of the voltage response and shifts in the resonant and phase-resonant frequencies that are not predicted by the corresponding linearized model. The differences between the nonlinear response and the linear prediction increase with increasing levels of the time scale separation between the voltage and the gating variable, and they almost disappear when both equations evolve at comparable rates. In contrast, voltage responses are almost insensitive to nonlinearities located in the gating variable equation. The method we develop provides a framework for the investigation of the preferred frequency responses in three-dimensional and nonlinear neuronal models as well as simple models of coupled neurons.

Functional brain abnormalities in major depressive disorder using the Hilbert-Huang transform.

PubMed

Yu, Haibin; Li, Feng; Wu, Tong; Li, Rui; Yao, Li; Wang, Chuanyue; Wu, Xia

2018-02-09

Major depressive disorder is a common disease worldwide, which is characterized by significant and persistent depression. Non-invasive accessory diagnosis of depression can be performed by resting-state functional magnetic resonance imaging (rs-fMRI). However, the fMRI signal may not satisfy linearity and stationarity. The Hilbert-Huang transform (HHT) is an adaptive time-frequency localization analysis method suitable for nonlinear and non-stationary signals. The objective of this study was to apply the HHT to rs-fMRI to find the abnormal brain areas of patients with depression. A total of 35 patients with depression and 37 healthy controls were subjected to rs-fMRI. The HHT was performed to extract the Hilbert-weighted mean frequency of the rs-fMRI signals, and multivariate receiver operating characteristic analysis was applied to find the abnormal brain regions with high sensitivity and specificity. We observed differences in Hilbert-weighted mean frequency between the patients and healthy controls mainly in the right hippocampus, right parahippocampal gyrus, left amygdala, and left and right caudate nucleus. Subsequently, the above-mentioned regions were included in the results obtained from the compared region homogeneity and the fractional amplitude of low frequency fluctuation method. We found brain regions with differences in the Hilbert-weighted mean frequency, and examined their sensitivity and specificity, which suggested a potential neuroimaging biomarker to distinguish between patients with depression and healthy controls. We further clarified the pathophysiological abnormality of these regions for the population with major depressive disorder.

Emotion avoidance in patients with anorexia nervosa: initial test of a functional model.

PubMed

Wildes, Jennifer E; Ringham, Rebecca M; Marcus, Marsha D

2010-07-01

This study aimed to evaluate emotion avoidance in patients with anorexia nervosa (AN) and to examine whether emotion avoidance helps to explain (i.e., mediates) the relation between depressive and anxiety symptoms and eating disorder (ED) psychopathology in this group. Seventy-five patients with AN completed questionnaires to assess study variables. Rates of emotion avoidance were compared to published data, and regression models were used to test the hypothesis that emotion avoidance mediates the relation between depressive and anxiety symptoms and ED psychopathology in AN. Patients with AN endorsed levels of emotion avoidance that were comparable to or higher than other psychiatric populations and exceeded community controls. As predicted, emotion avoidance significantly explained the relations of depressive and anxiety symptoms to ED psychopathology. Findings confirm that emotion avoidance is present in patients with AN and provide initial support for the idea that anorexic symptoms function, in part, to help individuals avoid aversive emotional states. 2009 by Wiley Periodicals, Inc.

Adolescent suicidal ideation.

PubMed

Field, T; Diego, M; Sanders, C E

2001-01-01

Adolescent suicidal ideation and its relationship to other variables was tapped by a self-report questionnaire administered to 88 high school seniors. Eighteen percent responded positively to the statement "sometimes I feel suicidal." Those who reported suicidal ideation were found to differ from those who did not on a number of variables, including family relationships (quality of relationship with mother, intimacy with parents, and closeness to siblings), family history of depression (maternal depression), peer relations (quality of peer relationships, popularity, and number of friends), emotional well-being (happiness, anger, and depression), drug use (cigarettes, marijuana, and cocaine), and grade point average. Stepwise regression indicated that happiness explained 46% of the variance in suicidal ideation, and number of friends, anger, and marijuana use explained an additional 20%, for a total of 66% of the variance. While 34% of the variance remained unexplained, it is suggested that the questions used to measure these four variables be included in global screenings to identify adolescents at risk for suicidal ideation.

Non-Linear Dynamics of Saturn's Rings

NASA Astrophysics Data System (ADS)

Esposito, L. W.

2015-12-01

Non-linear processes can explain why Saturn's rings are so active and dynamic. Some of this non-linearity is captured in a simple Predator-Prey Model: Periodic forcing from the moon causes streamline crowding; This damps the relative velocity, and allows aggregates to grow. About a quarter phase later, the aggregates stir the system to higher relative velocity and the limit cycle repeats each orbit, with relative velocity ranging from nearly zero to a multiple of the orbit average: 2-10x is possible. Summary of Halo Results: A predator-prey model for ring dynamics produces transient structures like 'straw' that can explain the halo structure and spectroscopy: Cyclic velocity changes cause perturbed regions to reach higher collision speeds at some orbital phases, which preferentially removes small regolith particles; Surrounding particles diffuse back too slowly to erase the effect: this gives the halo morphology; This requires energetic collisions (v ≈ 10m/sec, with throw distances about 200km, implying objects of scale R ≈ 20km); We propose 'straw', as observed ny Cassini cameras. Transform to Duffing Eqn : With the coordinate transformation, z = M2/3, the Predator-Prey equations can be combined to form a single second-order differential equation with harmonic resonance forcing. Ring dynamics and history implications: Moon-triggered clumping at perturbed regions in Saturn's rings creates both high velocity dispersion and large aggregates at these distances, explaining both small and large particles observed there. This confirms the triple architecture of ring particles: a broad size distribution of particles; these aggregate into temporary rubble piles; coated by a regolith of dust. We calculate the stationary size distribution using a cell-to-cell mapping procedure that converts the phase-plane trajectories to a Markov chain. Approximating the Markov chain as an asymmetric random walk with reflecting boundaries allows us to determine the power law index from results of numerical simulations in the tidal environment surrounding Saturn. Aggregates can explain many dynamic aspects of the rings and can renew rings by shielding and recycling the material within them, depending on how long the mass is sequestered. We can ask: Are Saturn's rings a chaotic non-linear driven system?

Self-esteem, negative emotionality, and depression as a common temperamental core: a study of mid-adolescent twin girls.

PubMed

Neiss, Michelle B; Stevenson, Jim; Legrand, Lisa N; Iacono, William G; Sedikides, Constantine

2009-04-01

We tested the structure and magnitude of genetic and environmental influences on the overlap among self-esteem, negative emotionality, and major depression symptoms in adolescent girls (N=706) from the Minnesota Twin Family Study. Genetic and environmental influences on all three operated via a general, heritable factor. Genetic influences explained the majority of overlap among the three constructs, as well as most of the variance in self-esteem and negative emotionality. Genetic influences on depression were more modest and largely due to genetic factors specific to depression. These findings support the theory that self-esteem, depression, and neuroticism represent aspects of a common temperamental core. The interrelations among the three constructs in mid-adolescence is consistent with their interrelations in adulthood.

Inbreeding Depression and Male Survivorship in Drosophila: Implications for Senescence Theory

PubMed Central

Swindell, William R.; Bouzat, Juan L.

2006-01-01

The extent to which inbreeding depression affects longevity and patterns of survivorship is an important issue from several research perspectives, including evolutionary biology, conservation biology, and the genetic analysis of quantitative traits. However, few previous inbreeding depression studies have considered longevity as a focal life-history trait. We maintained laboratory populations of Drosophila melanogaster at census population sizes of 2 and 10 male-female pairs for up to 66 generations and performed repeated assays of male survivorship throughout this time period. On average, significant levels of inbreeding depression were observed for median life span and age-specific mortality. For age-specific mortality, the severity of inbreeding depression increased over the life span. We found that a baseline inbreeding load of 0.307 lethal equivalents per gamete affected age-specific mortality, and that this value increased at a rate of 0.046 per day of the life span. With respect to some survivorship parameters, the differentiation of lineages was nonlinear with respect to the inbreeding coefficient, which suggested that nonadditive genetic variation contributed to variation among lineages. These findings provide insights into the genetic basis of longevity as a quantitative trait and have implications regarding the mutation-accumulation evolutionary explanation of senescence. PMID:16204222

Validation of the Center for Epidemiological Studies Depression Scale among Korean Adolescents.

PubMed

Heo, Eun-Hye; Choi, Kyeong-Sook; Yu, Je-Chun; Nam, Ji-Ae

2018-02-01

The Center for Epidemiological Studies Depression Scale (CES-D) is designed to measure the current level of depressive symptomatology in the general population. However, no review has examined whether the scale is reliable and valid among children and adolescents in Korea. The purpose of this study was to test whether the Korean form of the CES-D is valid in adolescents. Data were obtained from 1,884 adolescents attending grades 1-3 in Korean middle schools. Reliability was evaluated by internal consistency (Cronbach's alpha). Concurrent validity was evaluated by a correlation analysis between the CES-D and other scales. Construct validity was evaluated by exploratory factor and confirmatory factor analyses. The internal consistency coefficient for the entire group was 0.88. The CES-D was positively correlated with scales that measure negative psychological constructs, such as the State Anxiety Inventory for Children, the Korean Social Anxiety Scale for Children and Adolescents, and the Reynold Suicidal Ideation Questionnaire, but it was negatively correlated with scales that measure positive psychological constructs, such as the Korean version of the Rosenberg Self-Esteem Scale and the Connor-Davidson Resilience Scale-2. The CES-D was examined by three-dimensional exploratory factor analysis, and the three-factor structure of the scale explained 53.165% of the total variance. The variance explained by factor I was 24.836%, that explained by factor II was 15.988%, and that explained by factor III was 12.341%. The construct validity of the CES-D was tested by confirmatory factor analysis, and we applied the entire group's data using a three-factor hierarchical model. The fit index showed a level similar to those of other countries' adolescent samples. The CES-D has high internal consistency and addresses psychological constructs similar to those addressed by other scales. The CES-D showed a three-factor structure in an exploratory factor analysis. The present findings suggest that the CES-D is a useful and reliable tool for measuring depression in Korean adolescents.

Visual scanning behavior during processing of emotional faces in older adults with major depression.

PubMed

Noiret, Nicolas; Carvalho, Nicolas; Laurent, Éric; Vulliez, Lauriane; Bennabi, Djamila; Chopard, Gilles; Haffen, Emmanuel; Nicolier, Magali; Monnin, Julie; Vandel, Pierre

2015-01-01

Although several reported studies have suggested that younger adults with depression display depression-related biases during the processing of emotional faces, there remains a lack of data concerning these biases in older adults. The aim of our study was to assess scanning behavior during the processing of emotional faces in depressed older adults. Older adults with and without depression viewed happy, neutral or sad portraits during an eye movement recording. Depressed older adults spent less time with fewer fixations on emotional features than healthy older adults, but only for sad and neutral portraits, with no significant difference for happy portraits. These results suggest disengagement from sad and neutral faces in depressed older adults, which is not consistent with standard theoretical proposals on congruence biases in depression. Also, aging and associated emotional regulation change may explain the expression of depression-related biases. Our preliminary results suggest that information processing in depression consists of a more complex phenomenon than merely a general searching for mood-congruent stimuli or general disengagement from all kinds of stimuli. These findings underline that care must be used when evaluating potential variables, such as aging, which interact with depression and selectively influence the choice of relevant stimulus dimensions.

A face a mother could love: depression-related maternal neural responses to infant emotion faces.

PubMed

Laurent, Heidemarie K; Ablow, Jennifer C

2013-01-01

Depressed mothers show negatively biased responses to their infants' emotional bids, perhaps due to faulty processing of infant cues. This study is the first to examine depression-related differences in mothers' neural response to their own infant's emotion faces, considering both effects of perinatal depression history and current depressive symptoms. Primiparous mothers (n = 22), half of whom had a history of major depressive episodes (with one episode occurring during pregnancy and/or postpartum), were exposed to images of their own and unfamiliar infants' joy and distress faces during functional neuroimaging. Group differences (depression vs. no-depression) and continuous effects of current depressive symptoms were tested in relation to neural response to own infant emotion faces. Compared to mothers with no psychiatric diagnoses, those with depression showed blunted responses to their own infant's distress faces in the dorsal anterior cingulate cortex. Mothers with higher levels of current symptomatology showed reduced responses to their own infant's joy faces in the orbitofrontal cortex and insula. Current symptomatology also predicted lower responses to own infant joy-distress in left-sided prefrontal and insula/striatal regions. These deficits in self-regulatory and motivational response circuits may help explain parenting difficulties in depressed mothers.

[Depression status of academic high school students in Seoul: mediating role of entrapment].

PubMed

Park, Young-Joo; Shin, Nah-Mee; Han, Kuem-Sun; Kang, Hyun-Cheol; Cheon, Sook-Hee; Shin, Hyunjeong

2011-10-01

Purpose of this study was to investigate the status of depression in academic high school students and path analysis model for exploring the mediating role of entrapment to depression in relation to academic stress and perceived social support. Measurements were four reliable questionnaires measuring academic stress, social support, entrapment, and depression. Data were collected from students in 17 high schools in Seoul. Students (n=5,346) completing the questionnaires indicated depression & entrapment from academic stress. Depression was more prevalent in girls, those whose parents' household income was less than two million won, who did not live with father or mother or both due to divorce, separation, or death, and those who smoked or used alcohol. Entrapment was more prevalent in students similar to cases of depression and in seniors. According to the proposed path model, 48.6% of depression was explained by academic stress, social support, and entrapment. The indirect effect of entrapment as a mediator between academic stress and depression was verified and larger than the direct effect of academic stress on depression. Considering levels of depression and entrapment demonstrated by these students, better mental health programs with diverse strategies should be developed for their psychological well-being.

Nonlinear analysis of EEGs of patients with major depression during different emotional states.

PubMed

Akdemir Akar, Saime; Kara, Sadık; Agambayev, Sümeyra; Bilgiç, Vedat

2015-12-01

Although patients with major depressive disorder (MDD) have dysfunctions in cognitive behaviors and the regulation of emotions, the underlying brain dynamics of the pathophysiology are unclear. Therefore, nonlinear techniques can be used to understand the dynamic behavior of the EEG signals of MDD patients. To investigate and clarify the dynamics of MDD patients׳ brains during different emotional states, EEG recordings were analyzed using nonlinear techniques. The purpose of the present study was to assess whether there are different EEG complexities that discriminate between MDD patients and healthy controls during emotional processing. Therefore, nonlinear parameters, such as Katz fractal dimension (KFD), Higuchi fractal dimension (HFD), Shannon entropy (ShEn), Lempel-Ziv complexity (LZC) and Kolmogorov complexity (KC), were computed from the EEG signals of two groups under different experimental states: noise (negative emotional content) and music (positive emotional content) periods. First, higher complexity values were generated by MDD patients relative to controls. Significant differences were obtained in the frontal and parietal scalp locations using KFD (p<0.001), HFD (p<0.05), and LZC (p=0.05). Second, lower complexities were observed only in the controls when they were subjected to music compared to the resting baseline state in the frontal (p<0.05) and parietal (p=0.005) regions. In contrast, the LZC and KFD values of patients increased in the music period compared to the resting state in the frontal region (p<0.05). Third, the patients׳ brains had higher complexities when they were exposed to noise stimulus than did the controls׳ brains. Moreover, MDD patients׳ negative emotional bias was demonstrated by their higher brain complexities during the noise period than the music stimulus. Additionally, we found that the KFD, HFD and LZC values were more sensitive in discriminating between patients and controls than the ShEn and KC measures, according to the results of ANOVA and ROC calculations. It can be concluded that the nonlinear analysis may be a useful and discriminative tool in investigating the neuro-dynamic properties of the brain in patients with MDD during emotional stimulation. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Interaction Between Pubertal Timing and Peer Popularity for Boys and Girls: An Integration of Biological and Interpersonal Perspectives on Adolescent Depression.

PubMed

Teunissen, Hanneke A; Adelman, Caroline B; Prinstein, Mitchell J; Spijkerman, Renske; Poelen, Evelien A P; Engels, Rutger C M E; Scholte, Ron H J

2011-04-01

The transition to adolescence marks a time of sharply increased vulnerability to the development of depression, particularly among girls. Past research has examined isolated risk factors from individual theoretical models (e.g., biological, interpersonal, and cognitive) of depression, but few have examined integrative models. This study investigated the conjoint effects of early pubertal timing and popularity in the longitudinal prediction of depressive symptoms. A total of 319 girls and 294 boys (ages 11-14) provided information on their pubertal status, depressive symptoms, and the social status (i.e., popularity) of their peers. Adolescents completed a second measure of depressive symptoms 11 months after the initial time point. Findings supported an integrated biological-interpersonal model in explaining the development of depressive symptoms during adolescence. Early pubertal development was associated with increase in depressive symptoms only when accompanied by low levels of popularity. High levels of popularity buffered the association between early pubertal development and later depressive symptoms. Unexpectedly, these results were significant both for girls and boys. Results are discussed in terms of dynamic systems theories.

Relationship Between Postpartum Depression and Psychological and Biological Variables in the Initial Postpartum Period.

PubMed

Marín-Morales, Dolores; Toro-Molina, Susana; Peñacoba-Puente, Cecilia; Losa-Iglesias, Marta; Carmona-Monge, Francisco Javier

2018-06-01

Objectives The aims of this study were to evaluate the predictive relationship between psychological symptomatology 24 h postpartum and depression 4 months postpartum, and analyze the relationship between estradiol and postpartum mood. Methods Two hundred women participated in an assessment 24 h postpartum and gave a blood sample for estradiol analysis. One hundred eleven of these women completed the second assessment 4 months postpartum. The Beck Depression Inventory II and the Scale of State-Trait Anxiety were used to assess psychological symptoms. Results At 24 h postpartum, symptoms of depression, trait anxiety, and state anxiety were all significantly correlated with each other. Depression at 24 h postpartum was the only significant independent predictor of depression at 4 months postpartum, explaining 28.7% of the variance. No statistically significant relationship was found between levels of estradiol and mood. Symptoms of depression immediately postpartum thus appear to be a predictor of postpartum depression. Conclusions for Practice These results suggest that early postpartum psychological evaluation of the mother, and intervention as warranted, might prevent or lessen postpartum depression.

Theoretical considerations of some nonlinear aspects of hypersonic panel flutter

NASA Technical Reports Server (NTRS)

Mcintosh, S. C., Jr.

1974-01-01

A research project to analyze the effects of hypersonic nonlinear aerodynamic loading on panel flutter is reported. The test equipment and procedures for conducting the tests are explained. The effects of aerodynamic linearities on stability were evaluated by determining constant-initial-energy amplitude-sensitive stability boundaries and comparing them with the corresponding linear stability boundaries. An attempt to develop an alternative method of analysis for systems where amplitude-sensitive instability is possible is presented.

Chaos in World Politics: A Reflection

NASA Astrophysics Data System (ADS)

Ferreira, Manuel Alberto Martins; Filipe, José António Candeias Bonito; Coelho, Manuel F. P.; Pedro, Isabel C.

Chaos theory results from natural scientists' findings in the area of non-linear dynamics. The importance of related models has increased in the last decades, by studying the temporal evolution of non-linear systems. In consequence, chaos is one of the concepts that most rapidly have been expanded in what research topics respects. Considering that relationships in non-linear systems are unstable, chaos theory aims to understand and to explain this kind of unpredictable aspects of nature, social life, the uncertainties, the nonlinearities, the disorders and confusion, scientifically it represents a disarray connection, but basically it involves much more than that. The existing close relationship between change and time seems essential to understand what happens in the basics of chaos theory. In fact, this theory got a crucial role in the explanation of many phenomena. The relevance of this kind of theories has been well recognized to explain social phenomena and has permitted new advances in the study of social systems. Chaos theory has also been applied, particularly in the context of politics, in this area. The goal of this chapter is to make a reflection on chaos theory - and dynamical systems such as the theories of complexity - in terms of the interpretation of political issues, considering some kind of events in the political context and also considering the macro-strategic ideas of states positioning in the international stage.

Episodic memory and executive functioning in currently depressed patients compared to healthy controls.

PubMed

Pauls, Franz; Petermann, Franz; Lepach, Anja Christina

2015-01-01

At present, little is still known about the link between depression, memory and executive functioning. This study examined whether there are memory-related impairments in depressed patients and whether the size of such deficits depends on the age group and on specific types of cognitive measures. Memory performances of 215 clinically depressed patients were compared to the data of a matched control sample. Regression analyses were performed to determine the extent to which executive dysfunctions contributed to episodic memory impairments. When compared with healthy controls, significantly lower episodic memory and executive functioning performances were found for depressed patients of all age groups. Effect sizes appeared to vary across different memory and executive functioning measures. The extent to which executive dysfunctions could explain episodic memory impairments varied depending on the type of measure examined. These findings emphasise the need to consider memory-related functioning of depressed patients in the context of therapeutic treatments.

Gendered portraits of depression in Swedish newspapers.

PubMed

Bengs, Carita; Johansson, Eva; Danielsson, Ulla; Lehti, Arja; Hammarström, Anne

2008-07-01

Mass media are influential mediators of information, knowledge, and narratives of health and illness. In this article, we report on an examination of personal accounts of illness as presented in three Swedish newspapers, focusing on the gendered representation of laypersons' experiences of depression. A database search identified all articles mentioning depression during the year 2002. Twenty six articles focusing on personal experiences of depression were then subjected to a qualitative content analysis. We identified four themes: displaying a successful facade, experiencing a cracking facade, losing and regaining control, and explaining the illness. We found both similarities and differences with regard to gendered experiences. The mediated accounts of depression both upheld and challenged traditional gender stereotypes. The women's stories were more detailed, relational, emotionally oriented, and embodied. The portrayal of men was less emotional and expressive, and described a more dramatic onset of depression, reflecting hegemonic patterns of masculinity.

Temperament and character associated with depressive symptoms in women: analysis of two genetically informative samples.

PubMed

Yuh, Jongil; Neiderhiser, Jenae M; Lichtenstein, Paul; Hansson, Kjell; Cederblad, Marianne; Elthammer, Olle; Reiss, David

2009-09-01

Although previous research has explored associations between personality and depressive symptoms, a limited number of studies have assessed the extent to which genetic and environmental influences explain the association. This study investigated how temperament and character were associated with depressive symptoms in 131 pairs of twin and sibling women in early adulthood, as well as 326 pairs of twin women in middle adulthood. Results indicated that genetic influences accounted for a moderate to substantial percentage of the association between these personality features and depressive symptoms, emphasizing the role of genetic influences. Nonshared environmental influences made important contributions to the association between character and depressive symptoms, particularly in the sample of middle-aged twin women. These findings suggest that unique social experiences and relationships with a partner in adulthood may play an important role in these associations between character and depressive symptoms.

Self-conscious emotions and depression: rumination explains why shame but not guilt is maladaptive.

PubMed

Orth, Ulrich; Berking, Matthias; Burkhardt, Simone

2006-12-01

Feelings of shame and guilt are factors associated with depression. However, studies simultaneously investigating shame and guilt suggest that only shame has a strong unique effect, although it is not yet clear which psychological processes cause shame and not shame-free guilt to be related to depression. The authors hypothesized that shame, in contrast to guilt, elicits rumination, which then leads to depression. Therefore, in this study we investigated event-related shame and guilt, event-related rumination, and depression among 149 mothers and fathers following family breakup due to marital separation. Data were analyzed using latent variable modeling. The results confirm that shame but not guilt has a strong unique effect on depression. Moreover, the results show that the effect of shame is substantially mediated by rumination. The results are discussed against the background of self-discrepancies and self-esteem.

Metacognition in Pathological Gambling and Its Relationship with Anxious and Depressive Symptomatology.

PubMed

Jauregui, Paula; Urbiola, Irache; Estevez, Ana

2016-06-01

Gambling disorder is associated with elevated comorbidity with depressive and anxious disorders, and one variable that might help in the understanding of this association is metacognition. In the present study, the relationship between gambling and metacognition and the mediating role of metacognition in the relationship between gambling and depressive and anxious symptomatology were assessed. The sample comprised 124 pathological gamblers from centers that assist pathological gamblers and 204 participants from the general population. The results showed that pathological gamblers had higher levels of depressive and anxious symptomatology. Additionally, pathological gamblers had higher scores for positive beliefs about worry, negative beliefs of uncontrollability and danger, and beliefs about the need to control thoughts; these factors were also positively correlated with depressive and anxious symptomatology. Metacognition also fully mediated the association between gambling and depressive and anxious symptomatology. These results suggest that metacognition could contribute to explaining gambling disorder and the symptomatology associated with it.

Coffee and caffeine consumption and depression: A meta-analysis of observational studies.

PubMed

Wang, Longfei; Shen, Xiaoli; Wu, Yili; Zhang, Dongfeng

2016-03-01

The results from observation studies on the relationship between coffee intake and risk of depression and the relationship between caffeine consumption and depression remain controversial. We conducted a meta-analysis with a dose-response analysis to quantitatively summarize the evidence about the association between coffee and caffeine intakes and risk of depression. Relevant articles were identified by researching PubMed, Web of Science, China National Knowledge Infrastructure and WANFANG DATA in English or Chinese from 1 January 1980 to 1 May 2015. Case-control, cohort or cross-sectional studies evaluating coffee or caffeine consumption and depression were included. A random-effects model was used to combine study-specific relative risk and 95% confidence interval. Dose-response relationship was assessed by restricted cubic spline functions. Data were obtained from 11 observation articles; 330,677 participants from seven studies in seven articles were included in the coffee-depression analysis, while 38,223 participants from eight studies in seven articles were involved in the caffeine-depression analysis. Compared with the lowest level consumption, the pooled relative risk (95% confidence interval) for coffee-depression and caffeine-depression was 0.757 [0.624, 0.917] and 0.721 [0.522, 0.997], respectively. For dose-response analysis, evidence of a linear association was found between coffee consumption and depression, and the risk of depression decreased by 8% (relative risk = 0.92, 95% confidence interval = [0.87, 0.97], p = 0.002) for each cup/day increment in coffee intake; a nonlinear association was found between caffeine consumption and depression, the risk of depression decreased faster and the association became significant when the caffeine consumption was above 68 mg/day and below 509 mg/day. Coffee and caffeine consumption were significantly associated with decreased risk of depression. © The Royal Australian and New Zealand College of Psychiatrists 2015.

Cortisol and Depressive Symptoms in a Population-Based Cohort of Midlife Women

PubMed Central

Knight, Jennifer M.; Avery, Elizabeth F.; Janssen, Imke; Powell, Lynda H.

2010-01-01

Objective To determine whether there is a relationship between depressive symptoms and cortisol assessed at first morning awakening, 6PM, and 9PM in a population-based sample of midlife women. If this relationship is not linear, we aim to test whether this relationship is nonlinear, only present in those with more severe depressive symptoms, better accounted for by diurnal slope, or only apparent under uncontaminated conditions. Methods We investigated the cross-sectional association between cortisol and depressive symptoms, assessed by the Center for Epidemiological Studies Depression Scale (CES-D) in 408 midlife women (45.7% African-Americans, 54.3% white; mean age = 50.4) participating in the Chicago site of the Study of Women’s Health Across the Nation (SWAN). Results Diurnal cortisol slope is significantly flatter for women with higher CES-D scores than for less depressed women (p<.05 for the interaction). This relationship remains significant even after adjusting for age, smoking status, race, education, income, menopausal status, hormone replacement therapy (HRT), body mass index (BMI), medications, and wake time as well as possibly contaminating factors including physical activity, smoking, eating, or caffeine or alcohol consumption prior to saliva collection. Results using depression assessed categorically (CES-D cutoff ≥ 16) were similar to those using continuous depression in both unadjusted and adjusted analyses (p=.005 for the interaction of CES-D by time). Conclusions In this population-based sample of midlife women, greater depressive symptoms were associated with a significantly flatter diurnal cortisol slope than those with fewer symptoms, even after adjusting for covariates and possibly contaminating behaviors. PMID:20841562

Cortisol and depressive symptoms in a population-based cohort of midlife women.

PubMed

Knight, Jennifer M; Avery, Elizabeth F; Janssen, Imke; Powell, Lynda H

2010-11-01

To determine whether there is a relationship between depressive symptoms and cortisol assessed at first morning awakening, 6 PM, and 9 PM in a population-based sample of midlife women. If this relationship is not linear, we aim to test whether this relationship is nonlinear, only present in those with more severe depressive symptoms, better accounted for by diurnal slope, or only apparent under uncontaminated conditions. We investigated the cross-sectional association between cortisol and depressive symptoms, assessed by the Center for Epidemiological Studies Depression scale (CES-D) in 408 midlife women (45.7% African Americans, 54.3% white; mean age, 50.4 years) participating in the Chicago site of the Study of Women's Health Across the Nation. Diurnal cortisol slope is significantly flatter for women with higher CES-D scores than for less depressed women (p < .05 for the interaction). This relationship remains significant even after adjusting for age, smoking status, race, education, income, menopausal status, hormone replacement therapy, body mass index, medications, and wake time, as well as possibly contaminating factors, including physical activity, smoking, eating, or caffeine or alcohol consumption before saliva collection. Results using depression assessed categorically (CES-D cutoff ≥16) were similar to those using continuous depression in both unadjusted and adjusted analyses (p = .005 for the interaction of CES-D by time). In this population-based sample of midlife women, greater depressive symptoms were associated with a significantly flatter diurnal cortisol slope than those with fewer symptoms, even after adjusting for covariates and possibly contaminating behaviors.

Rumination mediates the relationship between overgeneral autobiographical memory and depression in patients with major depressive disorder.

PubMed

Liu, Yansong; Yu, Xinnian; Yang, Bixiu; Zhang, Fuquan; Zou, Wenhua; Na, Aiguo; Zhao, Xudong; Yin, Guangzhong

2017-03-21

Overgeneral autobiographical memory has been identified as a risk factor for the onset and maintenance of depression. However, little is known about the underlying mechanisms that might explain overgeneral autobiographical memory phenomenon in depression. The purpose of this study was to test the mediation effects of rumination on the relationship between overgeneral autobiographical memory and depressive symptoms. Specifically, the mediation effects of brooding and reflection subtypes of rumination were examined in patients with major depressive disorder. Eighty-seven patients with major depressive disorder completed the 17-item Hamilton Depression Rating Scale, Ruminative Response Scale, and Autobiographical Memory Test. Bootstrap mediation analysis for simple and multiple mediation models through the PROCESS macro was applied. Simple mediation analysis showed that rumination significantly mediated the relationship between overgeneral autobiographical memory and depression symptoms. Multiple mediation analyses showed that brooding, but not reflection, significantly mediated the relationship between overgeneral autobiographical memory and depression symptoms. Our results indicate that global rumination partly mediates the relationship between overgeneral autobiographical memory and depressive symptoms in patients with major depressive disorder. Furthermore, the present results suggest that the mediating role of rumination in the relationship between overgeneral autobiographical memory and depression is mainly due to the maladaptive brooding subtype of rumination.

Nonlinear analysis of EEG in major depression with fractal dimensions.

PubMed

Akar, Saime A; Kara, Sadik; Agambayev, Sumeyra; Bilgic, Vedat

2015-01-01

Major depressive disorder (MDD) is a psychiatric mood disorder characterized by cognitive and functional impairments in attention, concentration, learning and memory. In order to investigate and understand its underlying neural activities and pathophysiology, EEG methodologies can be used. In this study, we estimated the nonlinearity features of EEG in MDD patients to assess the dynamical properties underlying the frontal and parietal brain activity. EEG data were obtained from 16 patients and 15 matched healthy controls. A wavelet-chaos methodology was used for data analysis. First, EEGs of subjects were decomposed into 5 EEG sub-bands by discrete wavelet transform. Then, both the Katz's and Higuchi's fractal dimensions (KFD and HFD) were calculated as complexity measures for full-band and sub-bands EEGs. Last, two-way analyses of variances were used to test EEG complexity differences on each fractality measures. As a result, a significantly increased complexity was found in both parietal and frontal regions of MDD patients. This significantly increased complexity was observed not only in full-band activity but also in beta and gamma sub-bands of EEG. The findings of the present study indicate the possibility of using the wavelet-chaos methodology to discriminate the EEGs of MDD patients from healthy controls.

Impact of Physical and Sexual Abuse on Treatment Response in the Treatment of Resistant Depression in Adolescent Study (TORDIA)

ERIC Educational Resources Information Center

Shamseddeen, Wael; Asarnow, Joan Rosenbaum; Clarke, Gregory; Vitiello, Benedetto; Wagner, Karen Dineen; Birmaher, Boris; Keller, Martin B.; Emslie, Graham; Iyengar, Satish; Ryan, Neal D.; McCracken, James T.; Porta, Giovanna; Mayes, Taryn; Brent, David A.

2011-01-01

Objective: We previously reported that a history of abuse was associated with a poorer response to combination treatment in the Treatment of Resistant Depression in Adolescents study (TORDIA). We now report on the nature and correlates of abuse that might explain these findings. Method: Youth who did not benefit from an adequate selective…

Emotion Dysregulation Mediates the Longitudinal Relation between Peer Rejection and Depression: Differential Effects of Gender and Grade

ERIC Educational Resources Information Center

Fussner, Lauren M.; Luebbe, Aaron M.; Mancini, Kathryn J.; Becker, Stephen P.

2018-01-01

The goal of the current investigation was to test emotion dysregulation as a mechanism explaining the longitudinal association between peer rejection and depressive symptoms across 1 school year in middle childhood and to determine whether this process differed based on gender and grade. Youth in Grades 3 through 6 (N = 131; 71 girls) and their…

How Psychological Resources Mediate and Perceived Social Support Moderates the Relationship between Depressive Symptoms and Help-Seeking Intentions in College Students

ERIC Educational Resources Information Center

Kenny, Rachel; Dooley, Barbara; Fitzgerald, Amanda

2016-01-01

There is a high prevalence of depression among college students, which is linked to lower levels of help-seeking intentions. However, there has been a lack of research examining variables that may help explain this relationship. The present study aimed to address this gap by examining whether psychological resources (optimism and self-esteem)…

Human depression: a new approach in quantitative psychiatry

PubMed Central

2010-01-01

The biomolecular approach to major depression disorder is explained by the different steps that involve cell membrane viscosity, Gsα protein and tubulin. For the first time it is hypothesised that a biomolecular pathway exists, moving from cell membrane viscosity through Gsα protein and Tubulin, which can condition the conscious state and is measurable by electroencephalogram study of the brain's γ wave synchrony. PMID:20525273

Maternal postpartum depressive symptoms and infant externalizing and internalizing behaviors.

PubMed

Vafai, Yassaman; Steinberg, Julia R; Shenassa, Edmond D

2016-02-01

Maternal postpartum depression has been shown to be one of the main predictors of externalizing and internalizing behaviors in toddlers and adolescents. Research suggests that presence of such behaviors can be observed as early as infancy. The current study uses longitudinal data from 247 mothers to examine the relationship between postpartum depressive symptoms at 8 weeks and the infant's externalizing and internalizing behaviors at 12 months. In unadjusted linear regression models, there were associations between postpartum depressive symptoms and infant externalizing behaviors (β=0.082, SE=0.032, p=0.012) and internalizing behaviors (β=0.111, SE=0.037, p=0.003). After controlling for potential confounding factors, including maternal age, race, education, home ownership, smoking status in the postpartum period, marital status, parenting stress, and happiness from becoming a parent, the associations between postpartum depressive symptoms and infant externalizing (β=0.051, SE=0.034, p=0.138) and internalizing behaviors (β=0.077, SE=0.040, p=0.057) were reduced and became non-significant. Furthermore, in these models the total amount of variance explained was 17.2% (p<0.0001) for externalizing behaviors and 10.5% (p<0.01) for internalizing behaviors; the only significant predictor of externalizing behaviors was maternal age (β=-0.074, SE=0.030, p=0.014), and of internalizing behaviors was white non-Hispanic ethnicity (β=-1.33, SE=0.378, p=0.0005). A combined effect of the confounding factors seems to explain the finding of no significant independent association between postpartum depressive symptoms and infant externalizing and internalizing behaviors. Copyright © 2015 Elsevier Inc. All rights reserved.

Which tinnitus-related aspects are relevant for quality of life and depression: results from a large international multicentre sample

PubMed Central

2014-01-01

Background The aim of the present study was to investigate, which aspects of tinnitus are most relevant for impairment of quality of life. For this purpose we analysed how responses to the Tinnitus Handicap Inventory (THI) and to the question “How much of a problem is your tinnitus at present” correlate with the different aspects of quality of life and depression. Methods 1274 patients of the Tinnitus Research Initiative database were eligible for analysis. The Tinnitus Research Initiative database is composed of eight study centres from five countries. We assessed to which extent the Tinnitus Handicap Inventory (THI) and its subscales and single items as well as the tinnitus severity correlate with Beck Depression Inventory (BDI) score and different domains of the short version of the WHO-Quality of Life questionnaire (WHO-QoL Bref) by means of simple and multiple linear regression models. Results The THI explained considerable portions of the variance of the WHO-QoL Physical Health (R2 = 0.39) and Psychological Health (R2 = 0.40) and the BDI (R2 = 0.46). Furthermore, multiple linear regression models which included each THI item separately explained an additional 5% of the variance compared to the THI total score. The items feeling confused from tinnitus, the trouble of falling asleep at night, the interference with job or household responsibilities, getting upset from tinnitus, and the feeling of being depressed were those with the highest influence on quality of life and depression. The single question with regard to tinnitus severity explained 18%, 16%, and 20% of the variance of Physical Health, Psychological Health, and BDI respectively. Conclusions In the context of a cross-sectional correlation analysis, our findings confirmed the strong and consistent relationships between self-reported tinnitus burden and both quality of life, and depression. The single question “How much of a problem is your tinnitus” reflects tinnitus-related impairment in quality of life and can thus be recommended for use in clinical routine. PMID:24422941

Which tinnitus-related aspects are relevant for quality of life and depression: results from a large international multicentre sample.

PubMed

Zeman, Florian; Koller, Michael; Langguth, Berthold; Landgrebe, Michael

2014-01-14

The aim of the present study was to investigate, which aspects of tinnitus are most relevant for impairment of quality of life. For this purpose we analysed how responses to the Tinnitus Handicap Inventory (THI) and to the question "How much of a problem is your tinnitus at present" correlate with the different aspects of quality of life and depression. 1274 patients of the Tinnitus Research Initiative database were eligible for analysis. The Tinnitus Research Initiative database is composed of eight study centres from five countries. We assessed to which extent the Tinnitus Handicap Inventory (THI) and its subscales and single items as well as the tinnitus severity correlate with Beck Depression Inventory (BDI) score and different domains of the short version of the WHO-Quality of Life questionnaire (WHO-QoL Bref) by means of simple and multiple linear regression models. The THI explained considerable portions of the variance of the WHO-QoL Physical Health (R2 = 0.39) and Psychological Health (R2 = 0.40) and the BDI (R2 = 0.46). Furthermore, multiple linear regression models which included each THI item separately explained an additional 5% of the variance compared to the THI total score. The items feeling confused from tinnitus, the trouble of falling asleep at night, the interference with job or household responsibilities, getting upset from tinnitus, and the feeling of being depressed were those with the highest influence on quality of life and depression. The single question with regard to tinnitus severity explained 18%, 16%, and 20% of the variance of Physical Health, Psychological Health, and BDI respectively. In the context of a cross-sectional correlation analysis, our findings confirmed the strong and consistent relationships between self-reported tinnitus burden and both quality of life, and depression. The single question "How much of a problem is your tinnitus" reflects tinnitus-related impairment in quality of life and can thus be recommended for use in clinical routine.

Problems of simulation of large, long-lived vortices in the atmospheres of the giant planets (jupiter, saturn, neptune)

NASA Astrophysics Data System (ADS)

Nezlin, Michael V.; Sutyrin, Georgi G.

1994-01-01

Large, long-lived vortices are abundant in the atmospheres of the giant planets. Some of them survive a few orders of magnitude longer than the dispersive linear Rossby wave packets, e.g. the Great Red Spot (GRS), Little Red Spot (LRS) and White Ovals (WO) of Jupiter, Big Bertha, Brown Spot and Anne's Spot of Saturn, the Great Dark Spot (GDS) of Neptune, etc. Nonlinear effects which prevent their dispersion spreading are the main subject of our consideration. Particular emphasis is placed on determining the dynamical processes which may explain the remarkable properties of observed vortices such as anticyclonic rotation in preference to cyclonic one and the uniqueness of the GRS, the largest coherent vortex, along the perimeter of Jupiter at corresponding latitude. We review recent experimental and theoretical studies of steadily translating solitary Rossby vortices (anticyclones) in a rotating shallow fluid. Two-dimensional monopolar solitary vortices trap fluid which is transported westward. These dualistic structures appear to be vortices, on the one hand, and solitary “waves”, on the other hand. Owing to the presence of the trapped fluid, such solitary structures collide inelastically and have a memory of the initial disturbance which is responsible for the formation of the structure. As a consequence, they have no definite relationship between the amplitude and characteristic size. Their vortical properties are connected with geostrophic advection of local vorticity. Their solitary properties (nonspreading and stationary translation) are due to a balance between Rossby wave dispersion and nonlinear effects which allow the anticyclones, with an elevation of a free surface, to propagate faster than the linear waves, without a resonance with linear waves, i.e. without wave radiation. On the other hand, cyclones, with a depression of a free surface, are dispersive and nonstationary features. This asymmetry in dispersion-nonlinear properties of cyclones and anticyclones is thought to be one of the essential reasons for the observed predominance of anticyclones among the long-lived vortices in the atmospheres of the giant planets and also among the intrathermocline oceanic eddies. The effects of shear flows and differences between the properties of monopolar vortices in planetary flows and various laboratory experiments are discussed. General geostrophic (GG) theory of Rossby vortices is presented. It differs essentially from the traditional quasi-geostrophic (QG) and intermediate-geostrophic (IG) approximations by the account of (i) all scales between the deformation radius and the planetary scale and (ii) the arbitrary amplitudes of vortices. It is shown that, unlike QG- and IG-models, the GG-model allows for explaining the mentioned cyclonic-anticyclonic asymmetry not only in planetary flows, but also in laboratory modeling with vessels of near paraboloidal form.

Psychache and Suicide Ideation among Men Who Are Homeless: A Test of Shneidman's Model

ERIC Educational Resources Information Center

Patterson, Allisha A.; Holden, Ronald R.

2012-01-01

Suicide ideation among the homeless is 10 times more common than in the general population. Cognitive theories of depression and hopelessness propose to explain suicidality; however, as yet, none of these fully account for the phenomenon. Shneidman has suggested a theory of psychache or unbearable psychological pain to explain suicidality. This…

Exploring the relationships among performance-based functional ability, self-rated disability, perceived instrumental support, and depression: a structural equation model analysis.

PubMed

Weil, Joyce; Hutchinson, Susan R; Traxler, Karen

2014-11-01

Data from the Women's Health and Aging Study were used to test a model of factors explaining depressive symptomology. The primary purpose of the study was to explore the association between performance-based measures of functional ability and depression and to examine the role of self-rated physical difficulties and perceived instrumental support in mediating the relationship between performance-based functioning and depression. The inclusion of performance-based measures allows for the testing of functional ability as a clinical precursor to disability and depression: a critical, but rarely examined, association in the disablement process. Structural equation modeling supported the overall fit of the model and found an indirect relationship between performance-based functioning and depression, with perceived physical difficulties serving as a significant mediator. Our results highlight the complementary nature of performance-based and self-rated measures and the importance of including perception of self-rated physical difficulties when examining depression in older persons. © The Author(s) 2014.

Does worry moderate the relation between aggression and depression in adolescent girls?

PubMed

Blain-Arcaro, Christine; Vaillancourt, Tracy

2016-06-01

Aggressive girls, more so than aggressive boys, are at an increased risk for depression. Despite disconcerting outcomes, few researchers have examined factors that may attenuate or exacerbate the relation between aggression and depression. Competing hypotheses for explaining the role of worry in the relation between aggressive behaviour and depressive symptoms, commonly co-occurring problems in girls, have been proposed. In the present study, we examined worry as a possible moderator in the relation between girls nominated as aggressive by their peers and self-reported depressive symptoms in a sample of 226 girls aged 13 (M = 12.92, SD = 1.28) at Time 1. We found that worry exacerbated the risk of depressive symptoms concurrently and one year later for physically aggressive girls, but not relationally aggressive girls. These results suggest that worry plays an important role in the prediction of depression for aggressive girls, which varies by the form aggression takes. Copyright © 2016 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Mechanisms underlying REBT in mood disordered patients: predicting depression from the hybrid model of learning.

PubMed

Jackson, Chris J; Izadikah, Zahra; Oei, Tian P S

2012-06-01

Jackson's (2005, 2008a) hybrid model of learning identifies a number of learning mechanisms that lead to the emergence and maintenance of the balance between rationality and irrationality. We test a general hypothesis that Jackson's model will predict depressive symptoms, such that poor learning is related to depression. We draw comparisons between Jackson's model and Ellis' (2004) Rational Emotive Behavior Therapy and Theory (REBT) and thereby provide a set of testable learning mechanisms potentially underlying REBT. Results from 80 patients diagnosed with depression completed the learning styles profiler (LSP; Jackson, 2005) and two measures of depression. Results provide support for the proposed model of learning and further evidence that low rationality is a key predictor of depression. We conclude that the hybrid model of learning has the potential to explain some of the learning and cognitive processes related to the development and maintenance of irrational beliefs and depression. Copyright © 2011. Published by Elsevier B.V.

Subjective Sleep Quality as a Possible Mediator in the Relationship between Personality Traits and Depressive Symptoms in Middle-Aged Adults

PubMed Central

Peck, Katlyn; Mallya, Sasha; Lupien, Sonia J.

2016-01-01

This study explored the mediating role of sleep in the relationship between personality traits and depressive symptoms in a group of community-dwelling men and women (Mage = 57.92, SD = 4.00). Participants completed the short form NEO Five Factor Inventory (NEO-FFI), Pittsburgh Sleep Quality Index (PSQI), and the Center for Epidemiologic Studies Depression Scale (CES-D). High neuroticism and low conscientiousness was associated with poor sleep, as well as greater depressive symptom severity. Partial indirect mediation effects were found between personality traits (i.e., neuroticism and conscientiousness) and depressive symptoms through self-report sleep measures. An alternative model was also explored, entering depression as the mediator; however a smaller portion of the variance was explained by this model, compared with the hypothesized model. The current study provides preliminary information regarding the mechanisms that influence the relationship between personality traits, sleep, and depression among a group of community-dwelling middle-aged adults. Implications and future directions are discussed. PMID:27285159

Prenatal Depressive Symptoms and Toddler Behavior Problems: The Role of Maternal Sensitivity and Child Sex.

PubMed

Edwards, Renee C; Hans, Sydney L

2016-10-01

Increasing evidence suggests that maternal depression during pregnancy is associated with child behavioral outcomes even after accounting for later maternal depression. The purpose of this study was to examine various mechanisms, including maternal sensitivity, neonatal problems, and concurrent maternal depression, that might explain the association between prenatal maternal depressive symptoms and toddler behavior problems. Young, low income, African American mothers (n = 196) were interviewed during pregnancy and at 24-months postpartum, medical records were collected at the birth, and mother-child interactions were video-recorded at 24 months. Path analyses revealed that the association between prenatal depression and toddler behavior problems was mediated by maternal sensitivity and maternal depressive symptoms at 24 months. No evidence was found for a mediating effect of neonatal problems. Path models examining sex differences suggested that different mediating factors may be important for boys and girls, with boys being particularly susceptible to the effects of maternal sensitivity.

Real world ocean rogue waves explained without the modulational instability.

PubMed

Fedele, Francesco; Brennan, Joseph; Ponce de León, Sonia; Dudley, John; Dias, Frédéric

2016-06-21

Since the 1990s, the modulational instability has commonly been used to explain the occurrence of rogue waves that appear from nowhere in the open ocean. However, the importance of this instability in the context of ocean waves is not well established. This mechanism has been successfully studied in laboratory experiments and in mathematical studies, but there is no consensus on what actually takes place in the ocean. In this work, we question the oceanic relevance of this paradigm. In particular, we analyze several sets of field data in various European locations with various tools, and find that the main generation mechanism for rogue waves is the constructive interference of elementary waves enhanced by second-order bound nonlinearities and not the modulational instability. This implies that rogue waves are likely to be rare occurrences of weakly nonlinear random seas.

Real world ocean rogue waves explained without the modulational instability

PubMed Central

Fedele, Francesco; Brennan, Joseph; Ponce de León, Sonia; Dudley, John; Dias, Frédéric

2016-01-01

Since the 1990s, the modulational instability has commonly been used to explain the occurrence of rogue waves that appear from nowhere in the open ocean. However, the importance of this instability in the context of ocean waves is not well established. This mechanism has been successfully studied in laboratory experiments and in mathematical studies, but there is no consensus on what actually takes place in the ocean. In this work, we question the oceanic relevance of this paradigm. In particular, we analyze several sets of field data in various European locations with various tools, and find that the main generation mechanism for rogue waves is the constructive interference of elementary waves enhanced by second-order bound nonlinearities and not the modulational instability. This implies that rogue waves are likely to be rare occurrences of weakly nonlinear random seas. PMID:27323897

Analytic and computational modelling of super-radiant pulse compression in plasma and comparisons with experiment

NASA Astrophysics Data System (ADS)

Shvets, Gennady; Kalmykov, Serguei; Dreher, Matthias; Meyer-Ter-Vehn, Juergen

2003-10-01

The strongly non-linear regime of Raman backscattering [1,2] holds the promise of compressing long low-intensity laser beams into ultra-short high intensity pulses. As the short pulse is amplified by the long counter-propagating pump via backscattering the pump off the nonlinear plasma wave, its duration shrinks and intensity grows. The increase of the bandwidth of the amplified pulse only occurs in the nonlinear amplification regime, and is its most telling signature. Recent experiments at MPQ carried out in the strongly nonlinear regime reveal two previously unobserved features: (i) bandwidth expansion, and (ii) breakdown of the initially smooth amplified pulse into several spikes. Using semi-analytic model and particle-in-cell simulations, we explain the multiple pulse formation by the synchrotron motion of plasma electrons in the ponderomotive potential. Self-similar solutions consisting of multiple spikes are derived, and their nonlinear frequency shifts evaluated. The nonlinear focusing of the pulse by the pump is predicted and compared with experimental observations. [1] G. Shvets et. al., Phys. Rev. Lett. 81, 4879 (1998). [2] A. Pukhov, Rep. Progr. Phys. 66, 47 (1998).

Econometric testing on linear and nonlinear dynamic relation between stock prices and macroeconomy in China

NASA Astrophysics Data System (ADS)

Borjigin, Sumuya; Yang, Yating; Yang, Xiaoguang; Sun, Leilei

2018-03-01

Many researchers have realized that there is a strong correlation between stock prices and macroeconomy. In order to make this relationship clear, a lot of studies have been done. However, the causal relationship between stock prices and macroeconomy has still not been well explained. A key point is that, most of the existing research adopts linear and stable models to investigate the correlation of stock prices and macroeconomy, while the real causality of that may be nonlinear and dynamic. To fill this research gap, we investigate the nonlinear and dynamic causal relationships between stock prices and macroeconomy. Based on the case of China's stock prices and acroeconomy measures from January 1992 to March 2017, we compare the linear Granger causality test models with nonlinear ones. Results demonstrate that the nonlinear dynamic Granger causality is much stronger than linear Granger causality. From the perspective of nonlinear dynamic Granger causality, China's stock prices can be viewed as "national economic barometer". On the one hand, this study will encourage researchers to take nonlinearity and dynamics into account when they investigate the correlation of stock prices and macroeconomy; on the other hand, our research can guide regulators and investors to make better decisions.

Testing the Temporal Relationship Between Maternal and Adolescent Depressive and Anxiety Symptoms in a Community Sample

PubMed Central

Brown, Ruth C.; Clark, Shaunna L.; Dahne, Jennifer; Stratton, Kelcey J.; MacPherson, Laura; Lejuez, C. W.; Amstadter, Ananda B.

2014-01-01

Objective Transactional models have been used to explain the relationship between maternal depression and child behavioral problems; however, few studies have examined transactional models for maternal depression and adolescent depression and anxiety. Method Using an autoregressive cross-lagged analysis, we examined the longitudinal association between maternal and adolescent depression to determine the extent to which maternal depression influences adolescent depression and anxiety, and vice versa, over the course of a four-year period. Participants were a community sample of 277 mother-adolescent dyads with offspring aged 10–14 at the first year used in the analyses (43.7% female; 35% African American, 2.9% Hispanic/Latino). Depressive symptoms were assessed using maternal self-report (Center for Epidemiological Studies-Depression Scale [CESD]; Radloff, 1977), and adolescent depression and anxiety were assessed by self-report (Revised Child Anxiety and Depression Scale [RCADS]; Chorpita, Yim, Moffitt, Umemoto, & Francis, 2000). Results The final model, χ2 (14) = 23.74, p= .05; TLI= .97; CFI= .98; RMSEA= .05, indicated that maternal depression was significantly associated with adolescent depression two years later. Interestingly, adolescent depression did not significantly predict maternal depression, and the association between maternal and adolescent depression was not moderated by gender, age, or ethnicity. The association between maternal depression and adolescent anxiety was weaker than that observed for adolescent depression. Conclusions Results suggest that the transaction model of maternal depression may not extend to adolescent depression and anxiety. Furthermore, maternal depression can have an enduring effect on adolescent depression and continued research and clinical monitoring over extended periods of time is warranted. PMID:24702257

Depressive Symptoms Among Older Chinese Americans: Examining the Role of Acculturation and Family Dynamics.

PubMed

Sun, Fei; Gao, Xiang; Gao, Shuo; Li, Qilun; Hodge, David R

2018-06-14

This study identified the prevalence of depression and tested the influence of acculturation and family dynamics on depressive symptoms, among a community sample of older Chinese Americans. Data came from a survey of 385 Chinese Americans aged 55 and older (Mage = 72.4 years, SD = 8.7) living in a large metropolitan area in the American Southwest. The survey was administered in 2013 through face-to-face interviews. Depressive symptoms were assessed with the 12-item Center for Epidemiological Studies Depression scale. Approximately 19.5% of the sample reported mild depressive symptoms and an additional 8.5% reported moderate depressive symptoms. Three-step hierarchical regression analyses indicated that smaller family support network size and more family conflict were risk factors for depressive symptoms. The effect of acculturation was not significantly associated with depressive symptoms after controlling for family dynamics. Family support and conflict play a prominent role in explaining depressive symptoms among Chinese American older adults. The effect of acculturation is minimal when older adults have supportive families and good health. Interventions or services aimed at promoting family harmony for members of this population should be considered.

Perievent panic attack and depression after the World Trade Center disaster: a structural equation model analysis.

PubMed

Adams, Richard E; Boscarino, Joseph A

2011-01-01

Research suggests that perievent panic attacks--panic attacks in temporal proximity to traumatic events--are predictive of later mental health status, including the onset of depression. Using a community sample of New York City residents interviewed 1 year and 2 years after the World Trade Center Disaster, we estimated a structural equation model (SEM) using pre-disaster psychological status and post-disaster life events, together with psychosocial resources, to assess the relationship between perievent panic and later onset depression. Bivariate results revealed a significant association between perievent panic and both year-1 and year-2 depression. Results for the SEM, however showed that perievent panic was predictive of year-1 depression, but not year-2 depression, once potential confounders were controlled Year-2 stressors and year-2 psychosocial resources were the best predictors of year-2 depression onset. Pre-disaster psychological problems were directly implicated in year-1 depression, but not year-2 depression. We conclude that a conceptual model that includes pre- and post-disaster variables best explains the complex causal pathways between psychological status, stressor exposure, perievent panic attacks, and depression onset two years after the World Trade Center attacks.

The relationship of depression, anxiety and stress with low bone mineral density in post-menopausal women.

PubMed

Erez, Hany Burstein; Weller, Aron; Vaisman, Nachum; Kreitler, Shulamith

2012-01-01

The goal of the present study was to examine the relationships of depression, anxiety and stress with bone mineral density (BMD). We hypothesized negative relations between those mood variables and BMD in three assessed areas. The study showed association between depression and decreased BMD. The hypothesis regarding anxiety and stress was partially confirmed. In the last decade, the relationship of osteoporosis to psychological variables has been increasingly studied. The accumulating evidence from these studies supports the conclusion that depression is related to decreased BMD. Nevertheless, several studies found no support for this relationship. Moreover, only a small number of studies examined the association between anxiety or stress and decreased BMD. The goal of the present study was to examine the relationships of depression, anxiety and stress with BMD by means of adequate measuring instruments, while controlling for background factors known to be related to BMD decrease (e.g., body mass index, family history). The study included 135 post-menopausal female participants, who arrived for BMD screening, between the years 2006 and 2009. Several days prior to the examination, participants completed a series of questionnaires assessing depression and anxiety. BMD was measured using DXA, in spine, right and left hip. The study showed negative associations between depression and BMD variables in the three assessed areas. There were negative correlations between anxiety, stress and spine BMD, as well as a tendency towards negative relations in the right and left hip BMD. Concurrent hierarchical regressions showed that the addition of the three psychological variables increased the explained variance by 6–8 %. In addition, depression was found to have a unique significant contribution to the explained variance in right and left hip BMD. The findings provide supporting evidence for the existence of associations between mood variables and decreased BMD. Further research is required for gaining deeper insight into these relationships.

Depression: relationships to sleep paralysis and other sleep disturbances in a community sample

PubMed Central

Szklo-Coxe, Mariana; Young, Terry; Finn, Laurel; Mignot, Emmanuel

2009-01-01

SUMMARY Sleep disturbances are important correlates of depression, with epidemiologic research heretofore focused on insomnia and sleepiness. This epidemiologic study’s aim was to investigate, in a community sample, depression’s relationships to other sleep disturbances: sleep paralysis (SP), hypnagogic/hypnopompic hallucinations (HH), cataplexy – considered rapid eye movement-related disturbances – and automatic behavior (AB). Although typical of narcolepsy, these disturbances are prevalent, albeit under-studied, in the population. Cross-sectional analyses (1998–2002), based on Wisconsin Sleep Cohort Study population-based data from 866 participants (mean age 54, 53% male), examined: depression (Zung Self-Rating Depression Scale), trait anxiety (Spielberger State-Trait Anxiety Inventory, STAI-T ≥ 75th percentile), and self-reported sleep disturbances. Descriptive sleep data were obtained by overnight polysomnography. Adjusted logistic regression models estimated depression’s associations with each (>few times ever) outcome – SP, HH, AB, and cataplexy. Depression’s associations with self-reported SP and cataplexy were not explained by anxiety. After anxiety adjustment, severe depression (Zung ≥55), vis-à-vis Zung <50, increased SP odds ~500% (P = 0.0008). Depression (Zung ≥50), after stratification by anxiety given an interaction (P = 0.02), increased self-reported cataplexy odds in non-anxious (OR 8.9, P = 0.0008) but not anxious (OR 1.1, P = 0.82) participants. Insomnia and sleepiness seemed only partial mediators or confounders for depression’s associations with self-reported cataplexy and SP. Anxiety (OR 1.9, P = 0.04) partially explained depression’s (Zung ≥55) association with HH (OR 2.2, P = 0.08). Anxiety (OR 1.6, P = 0.02) was also more related than depression to AB. Recognizing depression’s relationships to oft-neglected sleep disturbances, most notably SP, might assist in better characterizing depression and the full range of its associated sleep problems in the population. Longitudinal studies are warranted to elucidate mediators and causality. PMID:17716279

Traveling wave solutions and conservation laws for nonlinear evolution equation

NASA Astrophysics Data System (ADS)

Baleanu, Dumitru; Inc, Mustafa; Yusuf, Abdullahi; Aliyu, Aliyu Isa

2018-02-01

In this work, the Riccati-Bernoulli sub-ordinary differential equation and modified tanh-coth methods are used to reach soliton solutions of the nonlinear evolution equation. We acquire new types of traveling wave solutions for the governing equation. We show that the equation is nonlinear self-adjoint by obtaining suitable substitution. Therefore, we construct conservation laws for the equation using new conservation theorem. The obtained solutions in this work may be used to explain and understand the physical nature of the wave spreads in the most dispersive medium. The constraint condition for the existence of solitons is stated. Some three dimensional figures for some of the acquired results are illustrated.

Reaction Force of Micro-scale Liquid Droplets Constrained Between Parallel Plates through CFD

NASA Astrophysics Data System (ADS)

Free, Robert; Hekiri, Haider; Hawa, Takumi

2012-02-01

Micro-scale liquid droplets responding to depression between parallel plates are investigated analytically and numerically. The functional dependence of the reaction force accrued in such droplets on droplet size, surface tension, depression amount, and contact angle is explored. For both the 2D and 3D case, an analytical model is developed based on first principles. Computational fluid dynamics is then utilized to evaluate the validity of these models. The reaction force is highly nonlinear, initially increasing very slowly with increasing depression of the droplet, but eventually moving asymptotically to infinity. The force scales linearly with both the droplet free radius and surface tension of the liquid, but has a much more complicated dependence on the contact angle and depression. Explicit expressions for the reaction force have been determined, showing these dependencies. The 3D model has been largely supported by the CFD results. It very accurately predicts the reaction force on the upper plate as the droplet is crushed, accounting for the effect of contact angle, surface tension, and droplet size.

Fluid nonlinear frequency shift of nonlinear ion acoustic waves in multi-ion species plasmas in the small wave number region

NASA Astrophysics Data System (ADS)

Feng, Q. S.; Xiao, C. Z.; Wang, Q.; Zheng, C. Y.; Liu, Z. J.; Cao, L. H.; He, X. T.

2016-08-01

The properties of the nonlinear frequency shift (NFS), especially the fluid NFS from the harmonic generation of the ion-acoustic wave (IAW) in multi-ion species plasmas, have been researched by Vlasov simulation. Pictures of the nonlinear frequency shift from harmonic generation and particle trapping are shown to explain the mechanism of NFS qualitatively. The theoretical model of the fluid NFS from harmonic generation in multi-ion species plasmas is given, and the results of Vlasov simulation are consistent with the theoretical result of multi-ion species plasmas. When the wave number k λD e is small, such as k λD e=0.1 , the fluid NFS dominates in the total NFS and will reach as large as nearly 15 % when the wave amplitude |e ϕ / Te|˜0.1 , which indicates that in the condition of small k λD e , the fluid NFS dominates in the saturation of stimulated Brillouin scattering, especially when the nonlinear IAW amplitude is large.

Fluid nonlinear frequency shift of nonlinear ion acoustic waves in multi-ion species plasmas in the small wave number region.

PubMed

Feng, Q S; Xiao, C Z; Wang, Q; Zheng, C Y; Liu, Z J; Cao, L H; He, X T

2016-08-01

The properties of the nonlinear frequency shift (NFS), especially the fluid NFS from the harmonic generation of the ion-acoustic wave (IAW) in multi-ion species plasmas, have been researched by Vlasov simulation. Pictures of the nonlinear frequency shift from harmonic generation and particle trapping are shown to explain the mechanism of NFS qualitatively. The theoretical model of the fluid NFS from harmonic generation in multi-ion species plasmas is given, and the results of Vlasov simulation are consistent with the theoretical result of multi-ion species plasmas. When the wave number kλ_{De} is small, such as kλ_{De}=0.1, the fluid NFS dominates in the total NFS and will reach as large as nearly 15% when the wave amplitude |eϕ/T_{e}|∼0.1, which indicates that in the condition of small kλ_{De}, the fluid NFS dominates in the saturation of stimulated Brillouin scattering, especially when the nonlinear IAW amplitude is large.

Gamma-ray vortices from nonlinear inverse Thomson scattering of circularly polarized light.

PubMed

Taira, Yoshitaka; Hayakawa, Takehito; Katoh, Masahiro

2017-07-10

Inverse Thomson scattering is a well-known radiation process that produces high-energy photons both in nature and in the laboratory. Nonlinear inverse Thomson scattering occurring inside an intense light field is a process which generates higher harmonic photons. In this paper, we theoretically show that the higher harmonic gamma-ray produced by nonlinear inverse Thomson scattering of circularly polarized light is a gamma-ray vortex, which means that it possesses a helical wave front and carries orbital angular momentum. Our work explains a recent experimental result regarding nonlinear inverse Thomson scattering that clearly shows an annular intensity distribution as a remarkable feature of a vortex beam. Our work implies that gamma-ray vortices should be produced in various situations in astrophysics in which high-energy electrons and intense circularly polarized light fields coexist. Nonlinear inverse Thomson scattering is a promising radiation process for realizing a gamma-ray vortex source based on currently available laser and accelerator technologies, which would be an indispensable tool for exploring gamma-ray vortex science.

A new nonlinear model for pitch perception

NASA Astrophysics Data System (ADS)

Cartwright, Julyan H. E.; González, Diego L.; Piro, Oreste

The ability of the auditory system to perceive the fundamental frequency of a sound even when this frequency is removed from the stimulus is an interesting phenomenon related to the pitch of complex sounds. This capability is known as residue or virtual pitch perception and was first reported last century in the pioneering work of Seebeck. It is residue perception that allows one to listen to music with small transistor radios, which in general have a very poor and sometimes negligible response to low frequencies. The first attempt, due to von Helmholtz, to explain the residue as a nonlinear effect in the ear considered it to originate from difference combination tones. But later experiments showed that the residue does not coincide with a difference combination tone, and nonlinear theories were abandoned. However, in this paper we use recent results from the theory of nonlinear dynamical systems to show that physical frequencies produced by generic nonlinear oscillators acted upon by two independent periodic excitations can reproduce with great precision most of the experimental data about the residue.

Simultaneous Measurements of Harmonic Waves at Fatigue-Cracked Interfaces

NASA Astrophysics Data System (ADS)

Hyunjo, Jeong; Dan, Barnard

2011-08-01

Nonlinear harmonic waves generated at cracked interfaces are investigated theoretically and experimentally. A compact tension specimen is fabricated and the amplitude of the transmitted wave is analyzed as a function of position along the fatigued crack surface. In order to measure as many nonlinear harmonic components as possible, broadband lithium niobate (LiNbO3) transducers are employed together with a calibration technique for making absolute amplitude measurements with fluid-coupled receiving transducers. Cracked interfaces are shown to generate high acoustic nonlinearities, which are manifested as harmonics in the power spectrum of the received signal. The first subharmonic f/2 and the second harmonic 2f waves are found to be dominant nonlinear components for an incident toneburst signal of frequency f. To explain the observed nonlinear behavior, a partially closed crack is modeled by planar half interfaces that can account for crack parameters, such as crack opening displacement and crack surface conditions. The simulation results show reasonable agreement with the experimental results.

Study on Properties of Energy Spectra of the Molecular Crystals

NASA Astrophysics Data System (ADS)

Pang, Xiao-Feng; Chen, Xiang-Rong

The energy-spectra of nonlinear vibration of molecular crystals such as acetanilide have been calculated by using discrete nonlinear Schrödinger equation appropriate to the systems, containing various interactions. The energy levels including higher excited states are basically consistent with experimental values obtained by infrared absorption and Raman scattering in acetanilide. We further give the features of distribution of the energy-spectra for the acetanilide. Using the energy spectra we also explained well experimental results obtained by Careri et al..

Effect of epidemic spreading on species coexistence in spatial rock-paper-scissors games.

PubMed

Wang, Wen-Xu; Lai, Ying-Cheng; Grebogi, Celso

2010-04-01

A fundamental question in nonlinear science and evolutionary biology is how epidemic spreading may affect coexistence. We address this question in the framework of mobile species under cyclic competitions by investigating the roles of both intra- and interspecies spreading. A surprising finding is that intraspecies infection can strongly promote coexistence while interspecies spreading cannot. These results are quantified and a theoretical paradigm based on nonlinear partial differential equations is derived to explain the numerical results.

A cry in the dark: depressed mothers show reduced neural activation to their own infant’s cry

PubMed Central

Ablow, Jennifer C.

2012-01-01

This study investigated depression-related differences in primiparous mothers’ neural response to their own infant’s distress cues. Mothers diagnosed with major depressive disorder (n = 11) and comparison mothers with no diagnosable psychopathology (n = 11) were exposed to their own 18-months-old infant’s cry sound, as well as unfamiliar infant’s cry and control sound, during functional neuroimaging. Depressed mothers’ response to own infant cry greater than other sounds was compared to non-depressed mothers’ response in the whole brain [false discovery rate (FDR) corrected]. A continuous measure of self-reported depressive symptoms (CESD) was also tested as a predictor of maternal response. Non-depressed mothers activated to their own infant’s cry greater than control sound in a distributed network of para/limbic and prefrontal regions, whereas depressed mothers as a group failed to show activation. Non-depressed compared to depressed mothers showed significantly greater striatal (caudate, nucleus accumbens) and medial thalamic activation. Additionally, mothers with lower depressive symptoms activated more strongly in left orbitofrontal, dorsal anterior cingulate and medial superior frontal regions. Non-depressed compared to depressed mothers activated uniquely to own infant greater than other infant cry in occipital fusiform areas. Disturbance of these neural networks involved in emotional response and regulation may help to explain parenting deficits in depressed mothers. PMID:21208990

Rumination and behavioural factors in Parkinson's disease depression.

PubMed

Julien, Camille L; Rimes, Katharine A; Brown, Richard G

2016-03-01

Parkinson's disease is associated with high rates of depression. There is growing interest in non-pharmacological management including psychological approaches such as Cognitive Behaviour Therapy. To date, little research has investigated whether processes that underpin cognitive models of depression, on which such treatment is based, apply in patients with Parkinson's disease. The study aimed to investigate the contribution of core psychological factors to the presence and degree of depressive symptoms. 104 participants completed questionnaires measuring mood, motor disability and core psychological variables, including maladaptive assumptions, rumination, cognitive-behavioural avoidance, illness representations and cognitive-behavioural responses to symptoms. Regression analyses revealed that a small number of psychological factors accounted for the majority of depression variance, over and above that explained by overall disability. Participants reporting high levels of rumination, avoidance and symptom focusing experienced more severe depressive symptoms. In contrast, pervasive negative dysfunctional beliefs did not independently contribute to depression variance. Specific cognitive (rumination and symptom focusing) and behavioural (avoidance) processes may be key psychological markers of depression in Parkinson's disease and therefore offer important targets for tailored psychological interventions. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Explaining Intentions to Seek Help for Depressive Symptoms in the Context of Responsibility Message Framing.

PubMed

Lueck, Jennifer; Yzer, Marco

2018-08-01

U.S. college students are disproportionally affected by depression but typically do not seek help. To advance understanding of the role of health messages in shaping college students' help-seeking intentions, we used a reasoned action approach to experimentally investigate help-seeking intentions for depressive symptoms. Due to negative interpretation biases among those who suffer from depression, scholars have previously warned against attempts to decrease feelings of responsibility for one's depression in health messages. We tested the determinants of help-seeking intentions as a function of exposure to depression help-seeking messages that differed in responsibility cues. Findings revealed that in our sample low responsibility health message framing did not affect determinants of help-seeking intentions. We identified instrumental attitude (β = .53) and descriptive norms (β = .24) as determinants of intentions to seek help (R 2  = .42) across message conditions and across levels of depression. These findings indicate potentially important targets for messages that seek to increase help-seeking among depressed college students.

[Depressive disorders in dementia and mild cognitive impairments: is comorbidity a cause or a risk factor?].

PubMed

Preuss, U W; Siafarikas, N; Petrucci, M; Wong, W M

2009-07-01

Both depression and dementia occur by themselves or together in elderly subjects aged 65 and above. The aim of this review is to discuss several hypotheses which try to explain the frequent co-occurrence exceeding chance alone, based on a systematic literature search. A series of studies revealed potential biological similarities between both disorders which, however, were not found in all investigations. Lifetime history of depression can be considered as a distant risk factor for dementias. Depression occurs most frequently within one year before and after the onset of dementia, in which the association between both disorders is probably strongest. In a subgroup of subjects with more "cognitive reserve", depression was found to be a consequence of patient's realisation of beginning cognitive deficits. Several studies indicate that depression in Alzheimer and other dementia forms can be considered as a separate disease entity, as the clinical syndrome differs from depression in earlier periods of life. Studies on the therapy of depression in dementia have aroused increasing interest in recent years. Herewith, certain guidelines in the treatment of older patients with antidepressants must be followed.

Parent depressive symptomatology moderates the etiology of externalizing behavior in childhood: An examination of gene-environment interaction effects.

PubMed

Clark, D Angus; Klump, Kelly L; Burt, S Alexandra

2018-04-26

Parent depressive symptomatology is robust risk factor for externalizing behavior in childhood (Goodman et al., 2011). Although the precise mechanisms underlying this association have yet to be fully illuminated, there is some evidence that parent depression can impact externalizing behavior via both genetic and environmental pathways. In the current study, we investigated the extent to which genetic and environmental influences on externalizing behavior are moderated by parent depressive symptoms (i.e., genotype-environment interaction) in a sample of 2,060, 6- to 11-year-old twins. Results suggest that genetic influences explain more variance in externalizing behavior as maternal depressive symptoms increase, whereas shared environmental effects decrease. These findings were specific to maternal depressive symptoms, however, and did not extend to not paternal depressive symptoms. Findings are critical for understanding the role of parental depression as a risk factor for problematic child behavior, and informing programs that seek to minimize the impact of this risk factor. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Weight loss after head and neck cancer: A dynamic relationship with depressive symptoms.

PubMed

Van Liew, Julia R; Brock, Rebecca L; Christensen, Alan J; Karnell, Lucy Hynds; Pagedar, Nitin A; Funk, Gerry F

2017-02-01

Weight loss and depressive symptoms are critical head and neck cancer outcomes, yet their relation over the illness course is unclear. Associations between self-reported depressive symptoms and objective weight loss across the year after head and neck cancer diagnosis were examined using growth curve modeling techniques (n = 564). A reciprocal covariation pattern emerged-changes in depressive symptoms over time were associated with same-month changes in weight loss (t [1148] = 2.05; p = .041), and changes in weight loss were associated with same-month changes in depressive symptoms (t [556] = 2.43; p = .015). To the extent that depressive symptoms increased, patients lost incrementally more weight than was lost due to the passage of time and vice versa. Results also suggested that pain and eating-related quality of life might explain the reciprocal association between depressive symptoms and weight loss. In head and neck cancer, a transactional interplay between depressive symptoms and weight loss unfolds over time. © 2016 Wiley Periodicals, Inc. Head Neck 39: 370-379, 2017. © 2016 Wiley Periodicals, Inc.

[Dependency, abuse, and depression by gender in widowed elderly].

PubMed

Kim, Ok-Soo; Yang, Kyoung-Mi; Kim, Kye-Ha

2005-04-01

The purpose of this study was to investigate the effects of dependency and abuse on depression according to gender in widowed elderly. A convenient sample consisted of 246 widowed elderly who were more than 65 years old in four cities. Data was collected using a structured questionnaire from August to September, 2002. A dependency Scale developed by Ahn (1999) was used to measure the level of dependency. Emotional abuse and physical abuse were measured by 10 items for emotional abuse and 7 items for physical abuse selected out of the Conditions Scale of Elder Abuse. The level of depression was measured by the Geriatric Depression Scale (GDS). The SPSS WIN 11.0 version program was used for data analysis. In male widowed elderly, dependency affected depression indirectly through emotional abuse. While in female widowed elderly, dependency affected depression directly and affected emotional abuse indirectly. The study showed that dependency was the most explainable variable on depression in widowed female elderly. Therefore, it dependency should be assessed first in nursing intervention to relieve depression of widowed elderly.

Perinatal Depression – the Fourth Inflammatory Morbidity of Pregnancy? Theory and Literature Review

PubMed Central

Osborne, Lauren M.; Monk, Catherine

2015-01-01

Perinatal depression is one of the leading causes of maternal morbidity and mortality. The biological etiology of this disorder remains in question, despite considerable research into the contributions of hormonal imbalance, the role of monoamines, and dysregulation of the HPA axis. Because inflammation is known to be associated with major depression in men and non-perinatal women as well as with other important morbidities of pregnancy (such as preeclampsia, preterm birth, and gestational diabetes), and because these morbidities may correlate with perinatal depression, inflammation may be a common physiological pathway that can also help explain perinatal depression. In this paper, we review the theoretical background of inflammation in perinatal depression and then review the literature concerning immune and inflammatory factors in the etiology and course of perinatal depression. We close with recommendations for future studies in this still relatively unexplored area. Identification and understanding of a common pathophysiology between other pregnancy morbidities and perinatal depression would link physical and mental well-being, likely leading to better treatment and prevention. PMID:23608136

Differences in quality of life outcomes among depressed spinal cord injury trial participants.

PubMed

Tate, Denise G; Forchheimer, Martin; Bombardier, Charles H; Heinemann, Allen W; Neumann, Holly D; Fann, Jesse R

2015-02-01

To assess the role that treatment response plays in a randomized controlled trial of an antidepressant among people with spinal cord injury (SCI) diagnosed with major depressive disorder (MDD) in explaining quality of life (QOL), assessed both globally as life satisfaction and in terms of physical and mental health-related QOL. Multivariable analyses were conducted, controlling for demographic, neurologic, and participatory factors and perceived functional limitations. Rehabilitation centers. Of the 133 persons who were randomized into the Project to Improve Symptoms and Mood after Spinal Cord Injury randomized controlled trial, 124 participated in this study. All participants were between the ages of 18 and 64 years, at least 1 month post-SCI, met the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, criteria for MDD, and completed the core measures used in this study. Not applicable. The Satisfaction with Life Scale and the physical and mental component summary scores of the Medical Outcomes Study 12-Item Short-Form Health Survey. Reduction in depressive symptoms over the course of a 12-week trial was predictive of increased QOL, which was measured as life satisfaction and mental well-being, within the context of other explanatory factors. However, reduction in symptoms did not explain differences in physical well-being among those with MDD. Perceived functional disability explained all 3 indices of QOL. Greater recognition has been given to QOL outcomes as endpoints of clinical trials because these often reflect participants' reported outcomes. Our findings support the association of QOL to the reduction of depression symptoms among trial participants. This association differs depending on how QOL is defined and measured, with stronger relations observed with life satisfaction and mental well-being among those diagnosed with MDD. The lack of association between depression and physical well-being may be explained by participants' subjective interpretation of physical well-being after SCI and their expectations and perceptions of improved physical health-related QOL based on the use of assistive technology. Consistent with our findings, pain is likely to play a role in decreasing physical QOL among those with incomplete injuries. Practicing caution is suggested in using physical well-being as an endpoint in trials among people with SCI. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Linear Mechanisms and Pressure Fluctuations in Wall Turbulence

NASA Astrophysics Data System (ADS)

Septham, Kamthon; Morrison, Jonathan

2014-11-01

Full-domain, linear feedback control of turbulent channel flow at Reτ <= 400 via vU' at low wavenumbers is an effective method to attenuate turbulent channel flow such that it is relaminarised. The passivity-based control approach is adopted and explained by the conservative characteristics of the nonlinear terms contributing to the Reynolds-Orr equation (Sharma et al .Phys .Fluids 2011). The linear forcing acts on the wall-normal velocity field and thus the pressure field via the linear (rapid) source term of the Poisson equation for pressure fluctuations, 2U'∂v/∂x . The minimum required spanwise wavelength resolution without losing control is constant at λz+ = 125, based on the wall friction velocity at t = 0 . The result shows that the maximum forcing is located at y+ ~ 20 , corresponding to the location of the maximum in the mean-square pressure gradient. The effectiveness of linear control is qualitatively explained by Landahl's theory for timescales, in that the control proceeds via the shear interaction timescale which is much shorter than both the nonlinear and viscous timescales. The response of the rapid (linear) and slow (nonlinear) pressure fluctuations to the linear control is examined and discussed.

Stochastic Erosion of Fractal Structure in Nonlinear Dynamical Systems

NASA Astrophysics Data System (ADS)

Agarwal, S.; Wettlaufer, J. S.

2014-12-01

We analyze the effects of stochastic noise on the Lorenz-63 model in the chaotic regime to demonstrate a set of general issues arising in the interpretation of data from nonlinear dynamical systems typical in geophysics. The model is forced using both additive and multiplicative, white and colored noise and it is shown that, through a suitable choice of the noise intensity, both additive and multiplicative noise can produce similar dynamics. We use a recently developed measure, histogram distance, to show the similarity between the dynamics produced by additive and multiplicative forcing. This phenomenon, in a nonlinear fractal structure with chaotic dynamics can be explained by understanding how noise affects the Unstable Periodic Orbits (UPOs) of the system. For delta-correlated noise, the UPOs erode the fractal structure. In the presence of memory in the noise forcing, the time scale of the noise starts to interact with the period of some UPO and, depending on the noise intensity, stochastic resonance may be observed. This also explains the mixing in dissipative dynamical systems in presence of white noise; as the fractal structure is smoothed, the decay of correlations is enhanced, and hence the rate of mixing increases with noise intensity.

Lifetime victimization, hazardous drinking and depression among heterosexual and sexual minority women

PubMed Central

HUGHES, TONDA L.; JOHNSON, TIMOTHY P.; STEFFEN, ALANA D.; WILSNACK, SHARON C.; EVERETT, BETHANY

2016-01-01

Purpose Substantial research documents sexual-orientation-related mental health disparities, but relatively few studies have explored underlying causes of these disparities. The goals of this paper were to (1) understand how differences in sexual identity and victimization experiences influence risk of hazardous drinking and depression, and (2) describe variations across sexual minority subgroups. Methods We pooled data from the 2001 National Study of Health and Life Experiences of Women (NSHLEW) and the 2001 Chicago Health and Life Experiences of Women (CHLEW) study to compare rates of victimization, hazardous drinking, and depression between heterosexual women and sexual minority women (SMW), and to test the relationship between number of victimization experiences and the study outcomes in each of five sexual identity subgroups. Results Rates of each of the major study variables varied substantially by sexual identity, with bisexual and mostly heterosexual women showing significantly higher risk than heterosexual women on one or both of the study outcomes. Number of victimization experiences explained some, but not all, of the risk of hazardous drinking and depression among SMW. Conclusions Although victimization plays an important role, sexual-minority-specific stressors, such as stigma and discrimination, likely also helps explain substance use and mental health disparities among SMW. PMID:26789712

Determinants of subjective memory complaints in community-dwelling adults with mild-to-moderate traumatic brain injury.

PubMed

Bay, Esther; Kalpakjian, Claire; Giordani, Bruno

2012-01-01

This study sought to determine to what extent chronic stress, depression and neurobehavioural consequences explained post-TBI subjective memory complaints (SMC). An observational, cross-sectional design was used. One hundred and fifty-nine persons who were 1-36 months post-injury provided data using interviews, chart reviews and surveys. Predictor variables included the Center for Epidemiological Studies-Depression Scale (CES-D), Perceived Stress Scale (PSS-14) and sub-scales of the NFI. SMC, according to the Neurobehavioural Functioning Inventory (NFI), was the main outcome variable. SMC could best be explained by increased age, months-since-injury, chronic situational stress and the frequency of somatic and communication difficulties, not depression (R(2)= 0.780, F = 97.39, [8, 152], p < 0.001). These findings suggest that, for persons in the chronic phase of recovery from their TBI, specific determinants other than general adjustment issues may apply. These include: increased chronic stress, age, somatic symptoms and communication difficulties. Self-reported chronic situational stress is positively associated with self-reported memory complaints, as well as somatic and communication difficulties. The causal ordering of these relationships would be best understood with prospective designs using biological correlates of chronic stress to advance understanding of post-TBI depression in older adults.

Identification of Psychological Dysfunctions and Eating Disorders in Obese Women Seeking Weight Loss: Cross-Sectional Study

PubMed Central

Panchaud Cornut, Maude; Szymanski, Jennifer; Marques-Vidal, Pedro; Giusti, Vittorio

2014-01-01

Objective. The aim of this study is to analyse associations between eating behaviour and psychological dysfunctions in treatment-seeking obese patients and identify parameters for the development of diagnostic tools with regard to eating and psychological disorders. Design and Methods. Cross-sectional data were analysed from 138 obese women. Bulimic Investigatory Test of Edinburgh and Eating Disorder Inventory-2 assessed eating behaviours. Beck Depression Inventory II, Spielberger State-Trait Anxiety Inventory, form Y, Rathus Assertiveness Schedule, and Marks and Mathews Fear Questionnaire assessed psychological profile. Results. 61% of patients showed moderate or major depressive symptoms and 77% showed symptoms of anxiety. Half of the participants presented with a low degree of assertiveness. No correlation was found between psychological profile and age or anthropometric measurements. The prevalence and severity of depression, anxiety, and assertiveness increased with the degree of eating disorders. The feeling of ineffectiveness explained a large degree of score variance. It explained 30 to 50% of the variability of assertiveness, phobias, anxiety, and depression. Conclusion. Psychological dysfunctions had a high prevalence and their severity is correlated with degree of eating disorders. The feeling of ineffectiveness constitutes the major predictor of the psychological profile and could open new ways to develop screening tools. PMID:24737999

Physiologic and laboratory correlates of depression, anxiety, and poor sleep in liver cirrhosis.

PubMed

Ko, Fang-Yuan; Yang, Albert C; Tsai, Shih-Jen; Zhou, Yang; Xu, Lie-Ming

2013-01-22

Studies have shown psychological distress in patients with cirrhosis, yet no studies have evaluated the laboratory and physiologic correlates of psychological symptoms in cirrhosis. This study therefore measured both biochemistry data and heart rate variability (HRV) analyses, and aimed to identify the physiologic correlates of depression, anxiety, and poor sleep in cirrhosis. A total of 125 patients with cirrhosis and 55 healthy subjects were recruited. Each subject was assessed through routine biochemistry, 5-minutes ECG monitoring, and psychological ratings of depression, anxiety, and sleep. HRV analysis were used to evaluate autonomic functions. The relationship between depression, sleep, and physiologic correlates was assessed using a multiple regression analysis and stepwise method, controlling for age, duration of illness, and severity of cirrhosis. Reduced vagal-related HRV was found in patients with severe liver cirrhosis. Severity of cirrhosis measured by the Child-Pugh score was not correlated with depression or anxiety, and only had a weak correlation with poor sleep. The psychological distress in cirrhosis such as depression, anxiety, and insomnia were correlated specifically to increased levels of aspartate aminotransferase (AST), increased ratios of low frequency to high frequency power, or reduced nonlinear properties of HRV (α1 exponent of detrended fluctuation analysis). Increased serum AST and abnormal autonomic nervous activities by HRV analysis were associated with psychological distress in cirrhosis. Because AST is an important mediator of inflammatory process, further research is needed to delineate the role of inflammation in the cirrhosis comorbid with depression.

Physiologic and laboratory correlates of depression, anxiety, and poor sleep in liver cirrhosis

PubMed Central

2013-01-01

Background Studies have shown psychological distress in patients with cirrhosis, yet no studies have evaluated the laboratory and physiologic correlates of psychological symptoms in cirrhosis. This study therefore measured both biochemistry data and heart rate variability (HRV) analyses, and aimed to identify the physiologic correlates of depression, anxiety, and poor sleep in cirrhosis. Methods A total of 125 patients with cirrhosis and 55 healthy subjects were recruited. Each subject was assessed through routine biochemistry, 5-minutes ECG monitoring, and psychological ratings of depression, anxiety, and sleep. HRV analysis were used to evaluate autonomic functions. The relationship between depression, sleep, and physiologic correlates was assessed using a multiple regression analysis and stepwise method, controlling for age, duration of illness, and severity of cirrhosis. Results Reduced vagal-related HRV was found in patients with severe liver cirrhosis. Severity of cirrhosis measured by the Child-Pugh score was not correlated with depression or anxiety, and only had a weak correlation with poor sleep. The psychological distress in cirrhosis such as depression, anxiety, and insomnia were correlated specifically to increased levels of aspartate aminotransferase (AST), increased ratios of low frequency to high frequency power, or reduced nonlinear properties of HRV (α1 exponent of detrended fluctuation analysis). Conclusions Increased serum AST and abnormal autonomic nervous activities by HRV analysis were associated with psychological distress in cirrhosis. Because AST is an important mediator of inflammatory process, further research is needed to delineate the role of inflammation in the cirrhosis comorbid with depression. PMID:23339829

Changes in personality traits during treatment with sertraline or citalopram.

PubMed

Ekselius, L; Von Knorring, L

1999-05-01

Recent studies indicate that selective serotonin re-uptake inhibitors (SSRIs) reduce the symptoms accompanying personality disorders and modulate a normal personality. To examine the effect of two SSRIs, sertraline and citalopram, on personality traits in major depressed patients. Personality traits were evaluated at baseline and after six months using the Karolinska Scales of Personality (KSP). After treatment, significant changes in the direction of normalisation were seen in all scales. To determine whether the observed changes could be explained by improved depressive symptoms, multiple stepwise regressions with the separate KSP as dependent variables were performed. Improvements in depressive symptoms only accounted for 0-8.4% of the observed variance. In depressed patients treated with SSRIs significant effects are seen on personality traits measured by the KSP.

The association between negative self-descriptions and depressive symptomology: does culture make a difference?

PubMed

Saint Arnault, Denise; Sakamoto, Shinji; Moriwaki, Aiko

2005-04-01

Research findings that depressed Americans endorse more negative self-related adjectives than controls may be related to a shared self-enhancement cultural frame. This study examines the relationship between negative core self-descriptors and depressive symptoms in 79 Japanese and 50 American women. Americans had more positive self-descriptions and core self-descriptors; however, there were no cultural group differences in number of negative self-descriptors or core self-descriptors. There was a significant correlation between negative core self-descriptor and Beck Depression Inventory (BDI) for Americans only, explaining 10.6% of the BDI variance. Analysis of variance revealed that there was significant BDI group differences for American negative core self-descriptor only. Theoretical possibilities are discussed.

The Association Between Negative Self-Descriptions and Depressive Symptomology: Does Culture Make a Difference?

PubMed Central

Sakamoto, Shinji; Moriwaki, Aiko

2007-01-01

Research findings that depressed Americans endorse more negative self-related adjectives than controls may be related to a shared self-enhancement cultural frame. This study examines the relationship between negative core self-descriptors and depressive symptoms in 79 Japanese and 50 American women. Americans had more positive self-descriptions and core self-descriptors; however, there were no cultural group differences in number of negative self-descriptors or core self-descriptors. There was a significant correlation between negative core self-descriptor and Beck Depression Inventory (BDI) for Americans only, explaining 10.6% of the BDI variance. Analysis of variance revealed that there was significant BDI group differences for American negative core self-descriptor only. Theoretical possibilities are discussed. PMID:15902678

Assessing the prevalence of depression in Punjabi and English primary care attenders: the role of culture, physical illness and somatic symptoms.

PubMed

Bhui, Kamaldeep; Bhugra, Dinesh; Goldberg, David; Sauer, Justin; Tylee, Andre

2004-09-01

Previous studies exploring the prevalence of depression among South Asians reported inconsistent findings. Research artefacts due to sampling bias, measurements errors and a failure to include ethnographic methods may all explain this. We estimated the prevalence of depression, and variations of prevalence with culture, cultural adaptation, somatic symptoms and physical disability in a cross-sectional primary care survey of Punjabi and English attendees. We included a culture specific screening instrument, culturally adapted the instruments and offered bilingual interviews. We found that, compared with their English counterparts, depressive diagnoses were more common among Punjabis, Punjabi women, Punjabis with physical complaints and, contrary to expectation, even Punjabis with low scores for somatic symptoms.

The association of adverse childhood experiences with mid-life depressive symptoms and quality of life among incarcerated males: exploring multiple mediation.

PubMed

Skarupski, Kimberly A; Parisi, Jeanine M; Thorpe, Roland; Tanner, Elizabeth; Gross, Deborah

2016-01-01

To explore the association of experiencing death, trauma, and abuse during childhood with depressive symptoms and quality of life at mid-life among incarcerated men and to understand how current social support and coping strategies mediate the impact of childhood trauma histories on mental health. Study participants were 192 male inmates in a maximum security prison. Participants completed measures of adverse childhood experiences related to death, trauma, and abuse, and depressive symptoms and quality of life. Data were analyzed using multiple mediation modeling. Men who reported having experienced adverse childhood experiences reported more depressive symptoms and lower quality of life than their counterparts. The results showed that in models both unadjusted and adjusted for age, race, education, number of years served, and whether the inmate had a life sentence, the association between adverse childhood experiences and quality of life were partially explained by the total of the indirect effects (point estimate = -.5052; CI.95 = -1.0364, -.0429 and point estimate = -.7792; CI.95 = -1.6369, -.0381), primarily via social support. However, the associations between adverse childhood experiences and depressive symptoms were not explained by social support and coping. Adverse childhood experiences are associated with deleterious mental health effects in later life. Social support and coping partially mediate the association between adverse childhood experiences and quality of life. The high prevalence of childhood trauma among aging prison inmates warrants attention to increasing social support mechanisms to improve mental health.

Differentiating Burnout from Depression: Personality Matters!

PubMed Central

Melchers, Martin Christoph; Plieger, Thomas; Meermann, Rolf; Reuter, Martin

2015-01-01

Stress-related affective disorders have been identified as a core health problem of the twenty-first century. In the endeavor to identify vulnerability factors, personality has been discussed as a major factor explaining and predicting disorders like depression or burnout. An unsolved question is whether there are specific personality factors allowing differentiation of burnout from depression. The present study tested the relation between one of the most prominent, biological personality theories, Cloninger’s Temperament and Character Inventory, and common measures of burnout (Maslach Burnout Inventory General) and depression (Beck Depression Inventory 2) in a sample of German employees (N = 944) and a sample of inpatients (N = 425). Although the same personality traits (harm avoidance and self-directedness) were predominantly associated with burnout and depression, there was a much stronger association to depression than to burnout in both samples. Besides, we observed specific associations between personality traits and subcomponents of burnout. Our results underline differences in the association of burnout vs. depression to personality, which may mirror differences in scope. While symptoms of depression affect all aspects of life, burnout is supposed to be specifically related to the workplace and its requirements. The much stronger association of personality to depression can be important to select appropriate therapy methods and to develop a more specified treatment for burnout in comparison to depression. PMID:26321963

Additive genetic contribution to symptom dimensions in major depressive disorder.

PubMed

Pearson, Rahel; Palmer, Rohan H C; Brick, Leslie A; McGeary, John E; Knopik, Valerie S; Beevers, Christopher G

2016-05-01

Major depressive disorder (MDD) is a phenotypically heterogeneous disorder with a complex genetic architecture. In this study, genomic-relatedness-matrix restricted maximum-likelihood analysis (GREML) was used to investigate the extent to which variance in depression symptoms/symptom dimensions can be explained by variation in common single nucleotide polymorphisms (SNPs) in a sample of individuals with MDD (N = 1,558) who participated in the National Institute of Mental Health Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study. A principal components analysis of items from the Hamilton Rating Scale for Depression (HRSD) obtained prior to treatment revealed 4 depression symptom components: (a) appetite, (b) core depression symptoms (e.g., depressed mood, anhedonia), (c) insomnia, and (d) anxiety. These symptom dimensions were associated with SNP-based heritability (hSNP2) estimates of 30%, 14%, 30%, and 5%, respectively. Results indicated that the genetic contribution of common SNPs to depression symptom dimensions were not uniform. Appetite and insomnia symptoms in MDD had a relatively strong genetic contribution whereas the genetic contribution was relatively small for core depression and anxiety symptoms. While in need of replication, these results suggest that future gene discovery efforts may strongly benefit from parsing depression into its constituent parts. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Prosocial Behavior and Depression: a Case for Developmental Gender Differences.

PubMed

Alarcón, Gabriela; Forbes, Erika E

2017-06-01

Prosocial behavior and depression are related constructs that both increase during adolescence and display gender-specific effects. The current review surveys literature examining the association between depressive symptoms and prosociality, measured with behavioral economic paradigms, across development and proposes a theoretical model explaining a mechanism through which adolescent girls have higher risk for depression than boys. Relative to healthy controls, prosocial behavior is reduced in adults with major depressive disorder (MDD) but may be increased in adolescents with MDD. The relationship between non-clinical levels of depressive symptoms and prosocial behavior remains to be studied experimentally; however, self-reported prosocial behavior is negatively associated with depressive symptoms in non-clinical adolescents, which may suggest a shift in the relation of prosocial behavior and depressive symptoms across the non-clinical (i.e., negative) to clinical range (i.e., positive). The effect of gender on these developmental and clinical status shifts has not been studied but could have important implications for understanding the emergence of higher rates of depression in girls than boys during adolescence. We propose that girls are at heightened risk for depression due to higher social-evaluative concern and other-oriented prosocial motivation that emphasize the needs of others over the self, leading to more altruistic prosocial behavior (despite personal cost) and a higher burden that enables depressive symptoms.

Maternal Depression and Youth Internalizing and Externalizing Symptomatology: Severity and Chronicity of Past Maternal Depression and Current Maternal Depressive Symptoms

PubMed Central

O’Connor, Erin E.; Langer, David A.; Tompson, Martha C.

2017-01-01

Maternal depression is a well-documented risk factor for youth depression, and taking into account its severity and chronicity may provide important insight into the degree of risk conferred. This study explored the degree to which the severity/chronicity of maternal depression history explained variance in youth internalizing and externalizing symptoms above and beyond current maternal depressive symptoms among 171 youth (58% male) ages 8 to 12 over a span of three years. Severity and chronicity of past maternal depression and current maternal depressive symptoms were examined as predictors of parent-reported youth internalizing and externalizing symptomatology, as well as youth self-reported depressive symptoms. Severity and chronicity of past maternal depression did not account for additional variance in youth internalizing and externalizing symptoms at Time 1 beyond what was accounted for by maternal depressive symptoms at Time 1. Longitudinal growth curve modeling indicated that prior severity/chronicity of maternal depression predicted levels of youth internalizing and externalizing symptoms at each time point when controlling for current maternal depressive symptoms at each time point. Chronicity of maternal depression, apart from severity, also predicted rate of change in youth externalizing symptoms over time. These findings highlight the importance of screening and assessing for current maternal depressive symptoms, as well as the nature of past depressive episodes. Possible mechanisms underlying the association between severity/chronicity of maternal depression and youth outcomes, such as residual effects from depressive history on mother–child interactions, are discussed. PMID:27401880

Autistic Traits and Suicidal Thoughts, Plans, and Self-Harm in Late Adolescence: Population-Based Cohort Study.

PubMed

Culpin, Iryna; Mars, Becky; Pearson, Rebecca M; Golding, Jean; Heron, Jon; Bubak, Isidora; Carpenter, Peter; Magnusson, Cecilia; Gunnell, David; Rai, Dheeraj

2018-05-01

To examine the hypothesis that autism spectrum disorders (ASD) diagnosis and traits in childhood are associated with suicidal thoughts, plans and self-harm at 16 years, and that any observed associations are explained by depression at 12 years. We examined associations between ASD diagnosis and 4 dichotomized ASD traits (social communication, pragmatic language, repetitive behavior, and sociability) with suicidal and nonsuicidal self-harm, suicidal thoughts, and suicidal plans at age 16 years in 5,031 members of the United Kingdom-based birth cohort study the Avon Longitudinal Study of Parents and Children. We assessed whether any associations were explained by depressive symptoms in early adolescence measured by the Short Moods and Feelings Questionnaire at 12 years. Children with impaired social communication had a higher risk of self-harm with suicidal intent (relative risk [RR] = 2.14, 95% CI = 1.28-3.58), suicidal thoughts (RR = 1.42, 95% CI = 1.06-1.91), and suicidal plans (RR = 1.95, 95% CI = 1.09-3.47) by age 16 years as compared to those without. There was no evidence for an association between ASD diagnosis and outcomes, although these analyses were imprecise because of small numbers. There was also no evidence of an association between other autism traits and the outcomes. Approximately 32% of the total estimated association between social communication impairment and self-harm was explained by depressive symptoms at 12 years. Social communication impairments are an important autistic trait in relation to suicidality. Early identification and management of depression may be a preventative mechanism, and future research identifying other potentially modifiable mechanisms may lead to interventions against suicidal behavior in this high-risk group. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Somatic symptoms evoked by exam stress in university students: the role of alexithymia, neuroticism, anxiety and depression.

PubMed

Zunhammer, Matthias; Eberle, Hanna; Eichhammer, Peter; Busch, Volker

2013-01-01

The etiology of somatization is incompletely understood, but could be elucidated by models of psychosocial stress. Academic exam stress has effectively been applied as a naturalistic stress model, however its effect on somatization symptoms according to ICD-10 and DSM-IV criteria has not been reported so far. Baseline associations between somatization and personality traits, such as alexithymia, have been studied exhaustively. Nevertheless, it is largely unknown if personality traits have an explanatory value for stress induced somatization. This longitudinal, quasi-experimental study assessed the effects of university exams on somatization - and the reversal of effects after an exam-free period. Repeated-observations were obtained within 150 students, measuring symptom intensity before, during and after an exam period, according to the Screening for Somatoform Symptoms 7-day (SOMS-7d). Additionally, self-reports on health status were used to differentiate between medically explained and medically unexplained symptoms. Alexithymia, neuroticism, trait-anxiety and baseline depression were surveyed using the Toronto-Alexithymia Scale (TAS-20), the Big-Five Personality Interview (NEO-FFI), the State Trait Anxiety Inventory (STAI) and Beck's Depression Inventory (BDI-II). These traits were competitively tested for their ability to explain somatization increases under exam stress. Somatization significantly increased across a wide range of symptoms under exam stress, while health reports pointed towards a reduction in acute infections and injuries. Neuroticism, alexithymia, trait anxiety and depression explained variance in somatization at baseline, but only neuroticism was associated with symptom increases under exam stress. Exam stress is an effective psychosocial stress model inducing somatization. A comprehensive quantitative description of bodily symptoms under exam stress is supplied. The results do not support the stress-alexithymia hypothesis, but favor neuroticism as a personality trait of importance for somatization.

Somatic Symptoms Evoked by Exam Stress in University Students: The Role of Alexithymia, Neuroticism, Anxiety and Depression

PubMed Central

Zunhammer, Matthias; Eberle, Hanna; Eichhammer, Peter; Busch, Volker

2013-01-01

Objective The etiology of somatization is incompletely understood, but could be elucidated by models of psychosocial stress. Academic exam stress has effectively been applied as a naturalistic stress model, however its effect on somatization symptoms according to ICD-10 and DSM-IV criteria has not been reported so far. Baseline associations between somatization and personality traits, such as alexithymia, have been studied exhaustively. Nevertheless, it is largely unknown if personality traits have an explanatory value for stress induced somatization. Methods This longitudinal, quasi-experimental study assessed the effects of university exams on somatization — and the reversal of effects after an exam-free period. Repeated-observations were obtained within 150 students, measuring symptom intensity before, during and after an exam period, according to the Screening for Somatoform Symptoms 7-day (SOMS-7d). Additionally, self-reports on health status were used to differentiate between medically explained and medically unexplained symptoms. Alexithymia, neuroticism, trait-anxiety and baseline depression were surveyed using the Toronto-Alexithymia Scale (TAS-20), the Big-Five Personality Interview (NEO-FFI), the State Trait Anxiety Inventory (STAI) and Beck’s Depression Inventory (BDI-II). These traits were competitively tested for their ability to explain somatization increases under exam stress. Results Somatization significantly increased across a wide range of symptoms under exam stress, while health reports pointed towards a reduction in acute infections and injuries. Neuroticism, alexithymia, trait anxiety and depression explained variance in somatization at baseline, but only neuroticism was associated with symptom increases under exam stress. Conclusion Exam stress is an effective psychosocial stress model inducing somatization. A comprehensive quantitative description of bodily symptoms under exam stress is supplied. The results do not support the stress-alexithymia hypothesis, but favor neuroticism as a personality trait of importance for somatization. PMID:24367700

Cortical spreading depression: An enigma

NASA Astrophysics Data System (ADS)

Miura, R. M.; Huang, H.; Wylie, J. J.

2007-08-01

The brain is a complex organ with active components composed largely of neurons, glial cells, and blood vessels. There exists an enormous experimental and theoretical literature on the mechanisms involved in the functioning of the brain, but we still do not have a good understanding of how it works on a gross mechanistic level. In general, the brain maintains a homeostatic state with relatively small ion concentration changes, the major ions being sodium, potassium, and chloride. Calcium ions are present in smaller quantities but still play an important role in many phenomena. Cortical spreading depression (CSD for short) was discovered over 60 years ago by A.A.P. Leão, a Brazilian physiologist doing his doctoral research on epilepsy at Harvard University, “Spreading depression of activity in the cerebral cortex," J. Neurophysiol., 7 (1944), pp. 359-390. Cortical spreading depression is characterized by massive changes in ionic concentrations and slow nonlinear chemical waves, with speeds on the order of mm/min, in the cortex of different brain structures in various experimental animals. In humans, CSD is associated with migraine with aura, where a light scintillation in the visual field propagates, then disappears, and is followed by a sustained headache. To date, CSD remains an enigma, and further detailed experimental and theoretical investigations are needed to develop a comprehensive picture of the diverse mechanisms involved in producing CSD. A number of mechanisms have been hypothesized to be important for CSD wave propagation. In this paper, we briefly describe several characteristics of CSD wave propagation, and examine some of the mechanisms that are believed to be important, including ion diffusion, membrane ionic currents, osmotic effects, spatial buffering, neurotransmitter substances, gap junctions, metabolic pumps, and synaptic connections. Continuum models of CSD, consisting of coupled nonlinear diffusion equations for the ion concentrations, and a discrete lattice-Boltzmann method approach will be described. Also, we will describe some open problems and remaining challenges.

What predicts depression in cardiac patients: sociodemographic factors, disease severity or theoretical vulnerabilities?

PubMed

Doyle, F; McGee, H M; Conroy, R M; Delaney, M

2011-05-01

Depression is associated with increased cardiovascular risk in acute coronary syndrome (ACS) patients, but some argue that elevated depression is actually a marker of cardiovascular disease severity. Therefore, disease indices should better predict depression than established theoretical causes of depression (interpersonal life events, reinforcing events, cognitive distortions, type D personality). However, little theory-based research has been conducted in this area. In a cross-sectional design, ACS patients (n = 336) completed questionnaires assessing depression and psychosocial vulnerabilities. Nested logistic regression assessed the relative contribution of demographic or vulnerability factors, or disease indices or vulnerabilities to depression. In multivariate analysis, all vulnerabilities were independent significant predictors of depression (scoring above threshold on any scale, 48%). Demographic variables accounted for <1% of the variance of depression status, with vulnerabilities accounting for significantly more (pseudo R² = 0.16, χ²(change) = 150.9, df = 4, p < 0.001). Disease indices accounted for 7% of the variance in depression (pseudo R² = 0.07, χ² = 137.9, p < 0.001). However, adding the vulnerabilities increased the overall variance explained to 22% (pseudo R² = 0.22, χ² = 58.6, df = 4, p < 0.001). Theoretical vulnerabilities predicted depression status better than did either demographic or disease indices. The presence of these proximal causes of depression suggests that depression in ACS patients is not simply a result of cardiovascular disease severity.

Definitions and factors associated with subthreshold depressive conditions: a systematic review

PubMed Central

2012-01-01

Background Subthreshold depressive disorders (minor and subthrehold depression) have been defined in a wide range of forms, varying on the number of symptoms and duration required. Disability associated with these conditions has also been reported. Our aim was to review the different definitions and to determine factors associated with these conditions in order to clarify the nosological implications of these disorders. Methods A Medline search was conducted of the published literature between January 2001 and September 2011. Bibliographies of the retrieved papers were also analysed. Results There is a wide heterogeneity in the definition and diagnostic criteria of minor and subthreshold depression. Minor depression was defined according to DSM-IV criteria. Regarding subthreshold depression, also called subclinical depression or subsyndromal symptomatic depression, between 2 and 5 depressive symptoms were required for the diagnosis, and a minimum duration of 2 weeks. Significant impairment associated with subthreshold depressive conditions, as well as comorbidity with other mental disorders, has been described. Conclusions Depression as a disorder is better explained as a spectrum rather than as a collection of discrete categories. Minor and subthreshold depression are common conditions and patients falling below the diagnostic threshold experience significant difficulties in functioning and a negative impact on their quality of life. Current diagnostic systems need to reexamine the thresholds for depressive disorders and distinguish them from ordinary feelings of sadness. PMID:23110575

Predictors of health-related quality of life in people with amyotrophic lateral sclerosis.

PubMed

Sandstedt, Petter; Johansson, Sverker; Ytterberg, Charlotte; Ingre, Caroline; Holmqvist, Lotta Widén; Kierkegaard, Marie

2016-11-15

Knowledge of factors influencing health-related quality of life (HRQL) in people with amyotrophic lateral sclerosis (ALS) is important because some factors might be amenable to intervention. The aim was to describe and explore the effects of disease severity, fatigue, anxiety, depression, frequency of social and lifestyle activities, coping capacity and mechanical ventilator use on HRQL in people with ALS. Sixty people with ALS were enrolled in this cross-sectional study. Data were collected with questionnaires during home visits. The Sickness Impact Profile and the EuroQol Visual Analogue Scale were used to assess HRQL. Multivariate regression analyses explored associations between HRQL and independent factors. Low frequency of social and lifestyle activities, and severe disease, were associated with worse HRQL, explaining 57% of total variance in the Sickness Impact Profile physical score. Severe disease, weak coping capacity and anxiety and/or depression were associated with worse HRQL, explaining 33% of total variance in Sickness Impact Profile psychosocial score. Fatigue and mechanical ventilator use were associated with worse HRQL, explaining 17% of variance in the EuroQol Visual Analogue Scale. Knowledge and understanding of how frequency of social and lifestyle activities, disease severity, coping capacity, anxiety and/or depression, fatigue and ventilator use contribute to and predict self-rated HRQL can optimize person-centred care and support. Copyright © 2016 Elsevier B.V. All rights reserved.

Association of Depressive Symptoms and Heart Rate Variability in Vietnam War-Era Twins: A Longitudinal Twin Difference Study.

PubMed

Huang, Minxuan; Shah, Amit; Su, Shaoyong; Goldberg, Jack; Lampert, Rachel J; Levantsevych, Oleksiy M; Shallenberger, Lucy; Pimple, Pratik; Bremner, J Douglas; Vaccarino, Viola

2018-05-16

Depressive symptoms are associated with lower heart rate variability (HRV), an index of autonomic dysregulation, but the direction of the association remains unclear. To investigate the temporal association between depression and HRV. A longitudinal, cross-lagged twin difference study, with baseline assessments from March 2002 to March 2006 (visit 1) and a 7-year follow-up (visit 2) at an academic research center with participants recruited from a national twin registry. Twins (n = 166) from the Vietnam Era Twin Registry, who served in the US military during the Vietnam War, and were discordant for depression at baseline were recruited. At both visits, depressive symptoms were measured using the Beck Depression Inventory-II (BDI-II), and HRV was measured through 24-hour electrocardiogram monitoring. To assess the direction of the association, within-pair differences in multivariable mixed-effects regression models were examined, and standardized β coefficients for both pathways were calculated. The associations were evaluated separately in monozygotic and dizygotic twins. In the final analytic sample (N = 146), all participants were men, 138 (95%) were white, and the mean (SD) age was 54 (3) years at baseline. Results showed consistent associations between visit 1 HRV and visit 2 BDI score across all HRV domains and models (β coefficients ranging from -0.14 to -0.29), which were not explained by antidepressants or other participant characteristics. The magnitude of the association was similar in the opposite pathway linking visit 1 BDI score to visit 2 HRV, with β coefficients ranging from 0.05 to -0.30, but it was largely explained by antidepressant use. In stratified analysis by zygosity, significant associations were observed in monozygotic and dizygotic twins for the path linking visit 1 HRV to visit 2 BDI score, although the associations were slightly stronger in dizygotic twins. The association between depression and autonomic dysregulation, indexed by HRV, is bidirectional, with stronger evidence suggesting that autonomic function affects depression risk rather than vice versa. The opposite causal pathway from depression to lower HRV is mostly driven by antidepressant use. These findings highlight an important role of autonomic nervous system in the risk of depression and contribute new understanding of the mechanisms underlying the comorbidity of depression and cardiovascular disease.

Detecting depression among adolescents in Santiago, Chile: sex differences.

PubMed

Araya, Ricardo; Montero-Marin, Jesus; Barroilhet, Sergio; Fritsch, Rosemarie; Gaete, Jorge; Montgomery, Alan

2013-04-23

Depression among adolescents is common but most cases go undetected. Brief questionnaires offer an opportunity to identify probable cases but properly validated cut-off points are often unavailable, especially in non-western countries. Sex differences in the prevalence of depression become marked in adolescence and this needs to be accounted when establishing cut-off points. This study involved adolescents attending secondary state schools in Santiago, Chile. We compared the self-reported Beck Depression Inventory-II with a psychiatric interview to ascertain diagnosis. General psychometric features were estimated before establishing the criterion validity of the BDI-II. The BDI-II showed good psychometric properties with good internal consistency, a clear unidimensional factorial structure, and good capacity to discriminate between cases and non-cases of depression. Optimal cut-off points to establish caseness for depression were much higher for girls than boys. Sex discrepancies were primarily explained by differences in scores among those with depression rather than among those without depression. It is essential to validate scales with the populations intended to be used with. Sex differences are often ignored when applying cut-off points, leading to substantial misclassification. Early detection of depression is essential if we think that early intervention is a clinically important goal.

Depressive symptoms predict head and neck cancer survival: Examining plausible behavioral and biological pathways.

PubMed

Zimmaro, Lauren A; Sephton, Sandra E; Siwik, Chelsea J; Phillips, Kala M; Rebholz, Whitney N; Kraemer, Helena C; Giese-Davis, Janine; Wilson, Liz; Bumpous, Jeffrey M; Cash, Elizabeth D

2018-03-01

Head and neck cancers are associated with high rates of depression, which may increase the risk for poorer immediate and long-term outcomes. Here it was hypothesized that greater depressive symptoms would predict earlier mortality, and behavioral (treatment interruption) and biological (treatment response) mediators were examined. Patients (n = 134) reported depressive symptomatology at treatment planning. Clinical data were reviewed at the 2-year follow-up. Greater depressive symptoms were associated with significantly shorter survival (hazard ratio, 0.868; 95% confidence interval [CI], 0.819-0.921; P < .001), higher rates of chemoradiation interruption (odds ratio, 0.865; 95% CI, 0.774-0.966; P = .010), and poorer treatment response (odds ratio, 0.879; 95% CI, 0.803-0.963; P = .005). The poorer treatment response partially explained the depression-survival relation. Other known prognostic indicators did not challenge these results. Depressive symptoms at the time of treatment planning predict overall 2-year mortality. Effects are partly influenced by the treatment response. Depression screening and intervention may be beneficial. Future studies should examine parallel biological pathways linking depression to cancer survival, including endocrine disruption and inflammation. Cancer 2018;124:1053-60. © 2018 American Cancer Society. © 2018 American Cancer Society.

Observability and Controllability of Networks: Symmetry in Representations of Brains and Controllers for Epidemics

NASA Astrophysics Data System (ADS)

Schiff, Steven

Observability and controllability are essential concepts to the design of predictive observer models and feedback controllers of networked systems. We present a numerical and group representational framework, to quantify the observability and controllability of nonlinear networks with explicit symmetries that shows the connection between symmetries and nonlinear measures of observability and controllability. In addition to the topology of brain networks, we have advanced our ability to represent network nodes within the brain using conservation principles and more accurate biophysics that unifies the dynamics of spikes, seizures, and spreading depression. Lastly, we show how symmetries in controller design can be applied to infectious disease epidemics. NIH Grants 1R01EB014641, 1DP1HD086071.

Observation of ion acoustic multi-Peregrine solitons in multicomponent plasma with negative ions

NASA Astrophysics Data System (ADS)

Pathak, Pallabi; Sharma, Sumita K.; Nakamura, Y.; Bailung, H.

2017-12-01

The evolution of the multi-Peregrine soliton is investigated in a multicomponent plasma and found to be critically dependent on the initial bound state. Formation and splitting of Peregrine soliton, broadening of the frequency spectra provide clear evidence of nonlinear-dispersive focusing due to modulational instability, a generic mechanism for rogue wave formation in which amplitude and phase modulation grow as a result of interplay between nonlinearity and anomalous dispersion. We have shown that initial perturbation parameters (amplitude & temporal length) critically determine the number of solitons evolution. It is also found that a sufficiently long wavelength perturbation of high amplitude invoke strong nonlinearity to generate a supercontinuum state. Continuous Wavelet Transform (CWT) and Fast Fourier Transform (FFT) analysis of the experimental time series data clearly indicate the spatio-temporal localization and spectral broadening. We consider a model based on the frame work of Nonlinear Schrodinger equation (NLSE) to explain the experimental observations.

On the instability of a three-dimensional attachment-line boundary layer - Weakly nonlinear theory and a numerical approach

NASA Technical Reports Server (NTRS)

Hall, P.; Malik, M. R.

1986-01-01

The instability of a three-dimensional attachment-line boundary layer is considered in the nonlinear regime. Using weakly nonlinear theory, it is found that, apart from a small interval near the (linear) critical Reynolds number, finite-amplitude solutions bifurcate subcritically from the upper branch of the neutral curve. The time-dependent Navier-Stokes equations for the attachment-line flow have been solved using a Fourier-Chebyshev spectral method and the subcritical instability is found at wavenumbers that correspond to the upper branch. Both the theory and the numerical calculations show the existence of supercritical finite-amplitude (equilibrium) states near the lower branch which explains why the observed flow exhibits a preference for the lower branch modes. The effect of blowing and suction on nonlinear stability of the attachment-line boundary layer is also investigated.

On the instability of a 3-dimensional attachment line boundary layer: Weakly nonlinear theory and a numerical approach

NASA Technical Reports Server (NTRS)

Hall, P.; Malik, M. R.

1984-01-01

The instability of a three dimensional attachment line boundary layer is considered in the nonlinear regime. Using weakly nonlinear theory, it is found that, apart from a small interval near the (linear) critical Reynolds number, finite amplitude solutions bifurcate subcritically from the upper branch of the neutral curve. The time dependent Navier-Stokes equations for the attachment line flow have been solved using a Fourier-Chebyshev spectral method and the subcritical instability is found at wavenumbers that correspond to the upper branch. Both the theory and the numerical calculations show the existence of supercritical finite amplitude (equilibrium) states near the lower branch which explains why the observed flow exhibits a preference for the lower branch modes. The effect of blowing and suction on nonlinear stability of the attachment line boundary layer is also investigated.

Roles Played by Electrostatic Waves in Producing Radio Emissions

NASA Technical Reports Server (NTRS)

Cairns, Iver H.

2000-01-01

Processes in which electromagnetic radiation is produced directly or indirectly via intermediate waves are reviewed. It is shown that strict theoretical constraints exist for electrons to produce nonthermal levels of radiation directly by the Cerenkov or cyclotron resonances. In contrast, indirect emission processes in which intermediary plasma waves are converted into radiation are often favored on general and specific grounds. Four classes of mechanisms involving the conversion of electrostatic waves into radiation are linear mode conversion, hybrid linear/nonlinear mechanisms, nonlinear wave-wave and wave-particle processes, and radiation from localized wave packets. These processes are reviewed theoretically and observational evidence summarized for their occurrence. Strong evidence exists that specific nonlinear wave processes and mode conversion can explain quantitatively phenomena involving type III solar radio bursts and ionospheric emissions. On the other hand, no convincing evidence exists that magnetospheric continuum radiation is produced by mode conversion instead of nonlinear wave processes. Further research on these processes is needed.

Quality of life in patients with depression, panic syndrome, other anxiety syndrome, alcoholism and chronic somatic diseases: a longitudinal study in Slovenian primary care patients.

PubMed

Cerne, Anja; Rifel, Janez; Rotar-Pavlic, Danica; Svab, Igor; Selic, Polona; Kersnik, Janko

2013-01-01

To analyse the correlates between the quality of life and chronic diseases and socio-demographic characteristics of patients in family medicine with a special emphasis on depression, panic syndrome, other anxiety syndrome and alcoholism. In a longitudinal study, the data set of 516 family practice attendees recruited from 60 family practices was analysed. Depression, panic syndrome, other anxiety syndrome and alcoholism were diagnosed using appropriate diagnostic interviews. Quality of life was assessed using the SF-12 questionnaire, measuring a mental health score and a physical health score. Data about the number of chronic somatic diseases were obtained from the patients' medical records. Physical health score was negatively associated with higher age (β = -0.25, p < 0.001), depression (β = -0.20, p < 0.001) and number of chronic somatic diseases (β = -0.10, p < 0.016) and positively associated with higher education level (β = 0.21, p < 0.001), single marital status (β = 0.09, p < 0.022) and better financial status (β = 0.14, p < 0.001). Linear regression explained 31.8 % of the variance (R(2) = 0.318; p < 0.001). Similarly, mental health score was negatively associated with depression (β = -0.45, p < 0.001) and panic syndrome (β = -0.07, p < 0.001) and positively associated with male gender (β = 0.10, p < 0.015) and better financial status (β = 0.13, p < 0.001). Linear regression explained 45.5 % of the variance (R (2) = 0.455; p < 0.001). In family medicine, special attention should be directed to major depression, panic syndrome and number of chronic somatic diseases as they are associated with poorer quality of life.

Variables associated with sleep quality in chronic tension-type headache: A cross-sectional and longitudinal design.

PubMed

Benito-González, Elena; Palacios-Ceña, Maria; Fernández-Muñoz, Juan J; Castaldo, Matteo; Wang, Kelun; Catena, Antonella; Arendt-Nielsen, Lars; Fernández-de-Las-Peñas, César

2018-01-01

To investigate variables associated at baseline (cross-sectional design) and at one year (longitudinal design) with the quality of sleep in chronic tension-type headache (CTTH). One hundred and eighty (n = 180) and 135 individuals with CTTH participated in the cross-sectional and longitudinal design respectively. Clinical features were collected with a 4-weeks headache diary at baseline and one-year follow-up. Sleep quality was assessed at baseline and 1-year follow-up with the Pittsburgh Sleep Quality Index. Anxiety and depression (Hospital Anxiety and Depression Scale-HADS), burden of headache (Headache Disability Inventory-HDI), quality of life (SF-36 questionnaire), and pressure pain thresholds (PPTs) at trigeminal, extra-trigeminal and widespread area were assessed at baseline. Hierarchical regression analyses were conducted to determine the associations between variables at baseline and 1-year follow-up with sleep quality. At baseline positive correlations between sleep quality and headache intensity, headache frequency, headache duration, emotional and physical burden of headache and depression were observed. The regression analyses found that depression and emotional burden of headache explained 27.5% of the variance in sleep quality at baseline (r2 = .262; F = 23.72 P < .001). At one-year, sleep quality was significantly associated with baseline burden of headache, depression, widespread PPTs, vitality and mental health domains. Regression analyses revealed that vitality, PPT over the second metacarpal and PPT over the neck explained 30.0% of the variance of sleep quality at one-year (r2 = .269, F = 9.71, P < .001). It seems that sleep quality exhibits a complex interaction in individuals with CTTH since depression and the emotional burden were associated with sleep quality at baseline, but vitality and PPTs over extra-trigeminal areas were associated with the quality of sleep at one-year.

Gender-Specific Trends in Educational Attainment and Self-Rated Health, 1972–2002

PubMed Central

Hill, Terrence D.; Needham, Belinda L.

2006-01-01

Objectives. We tested whether self-rated health has improved over time (1972–2002) for women and men. We also considered the degree to which historical gains in educational attainment help to explain any observed trends. Methods. Using 21 years of repeated cross-sectional data from the General Social Survey, we estimated a series of ordered logistic regression models predicting self-rated health. Results. Our results show that women’s health status has steadily improved over the 30-year period under study, and these improvements are largely explained by gains in educational attainment. We also found that the health trend for men is nonlinear, suggesting significant fluctuations in health status over time. Conclusions. Based on the linear health status trend and strong mediation pattern for women, and the nonlinear health status trend for men, women have benefited more than men, in terms of self-rated health, from increased educational attainment. PMID:16735623

Predicting the changes in depressive symptomatology in later life: how much do changes in health status, marital and caregiving status, work and volunteering, and health-related behaviors contribute?

PubMed

Choi, Namkee G; Bohman, Thomas M

2007-02-01

This study examined the unique effects of four variable groups on changes in older adults' depressive symptoms for a 2-year period: (1) baseline health and disability status, (2) changes in health and disability since baseline, (3) stability and changes in marital and caregiving status and in work and volunteering, and (4) stability and changes in health-related behaviors. With data from the 1998 and 2000 interview waves of the Health and Retirement Study, the authors used gender-separate multistep (hierarchical) residualized regression analyses in which the Center for Epidemiological Studies Depression scale (CES-D) score at follow-up is modeled as a function of the effect of each group of independent variables. As hypothesized, changes in health, disability, marital, and caregiving status explained a larger amount of variance than the existing and stable conditions, although each group of variables explained a relatively small amount (0.3-3.4%) of variance in the follow-up CES-D score.

Symptom clusters in patients with high-grade glioma.

PubMed

Fox, Sherry W; Lyon, Debra; Farace, Elana

2007-01-01

To describe the co-occurring symptoms (depression, fatigue, pain, sleep disturbance, and cognitive impairment), quality of life (QoL), and functional status in patients with high-grade glioma. Correlational, descriptive study of 73 participants with high-grade glioma in the U.S. Nine brief measures were obtained with a mailed survey. Participants were recruited from the online message board of The Healing Exchange BRAIN TRUST, a nonprofit organization dedicated to improving quality of life for people with brain tumors. Two symptom cluster models were examined. Four co-occurring symptoms were significantly correlated with each other and explained 29% of the variance in QoL: depression, fatigue, sleep disturbance, and cognitive impairment. Depression, fatigue, sleep disturbance, cognitive impairment, and pain were significantly correlated with each other and explained 62% of the variance in functional status. The interrelationships of the symptoms examined in this study and their relationships with QoL and functional status meet the criteria for defining a symptom cluster. The differences in the models of QoL and functional status indicates that symptom clusters may have unique characteristics in patients with gliomas.

Developmental pathways to depressive symptoms in adolescence: A multi-wave prospective study of negative emotionality, stressors, and anxiety

PubMed Central

Barrocas, Andrea L.; Hankin, Benjamin L.

2014-01-01

This study examined two potential developmental pathways through which the temperament risk factor of negative emotionality (NE) leads to prospective increases in depressive symptoms through the mediating role of stressors and anxious symptoms in a sample of early to middle adolescents (N=350, 6th–10th graders). The primary hypothesized model was that baseline NE leads to increased stressors, which results in increases in anxious arousal, which culminates with elevated depressive symptoms. An alternate model hypothesized that baseline NE leads to increased anxious arousal, which results in increases in stressors, and this culminates in elevated depressive symptoms. Youth completed self-report measures of NE, stressors, anxious arousal, and depressive symptoms at four time-points. Path analysis supported the primary model and showed that the mediating influence of stressors and anxious arousal explained 78% of the association between NE and prospective elevations in depressive symptoms. The alternate model was not supported. Neither gender nor age were moderators. PMID:21249517

Schizophrenia and Depression Co-Morbidity: What We have Learned from Animal Models

PubMed Central

Samsom, James N.; Wong, Albert H. C.

2015-01-01

Patients with schizophrenia are at an increased risk for the development of depression. Overlap in the symptoms and genetic risk factors between the two disorders suggests a common etiological mechanism may underlie the presentation of comorbid depression in schizophrenia. Understanding these shared mechanisms will be important in informing the development of new treatments. Rodent models are powerful tools for understanding gene function as it relates to behavior. Examining rodent models relevant to both schizophrenia and depression reveals a number of common mechanisms. Current models which demonstrate endophenotypes of both schizophrenia and depression are reviewed here, including models of CUB and SUSHI multiple domains 1, PDZ and LIM domain 5, glutamate Delta 1 receptor, diabetic db/db mice, neuropeptide Y, disrupted in schizophrenia 1, and its interacting partners, reelin, maternal immune activation, and social isolation. Neurotransmission, brain connectivity, the immune system, the environment, and metabolism emerge as potential common mechanisms linking these models and potentially explaining comorbid depression in schizophrenia. PMID:25762938

Major Depressive Disorder and Dysthymia at the Intersection of Nativity and Racial-Ethnic Origins.

PubMed

Szaflarski, Magdalena; Cubbins, Lisa A; Bauldry, Shawn; Meganathan, Karthikeyan; Klepinger, Daniel H; Somoza, Eugene

2016-08-01

Immigrants often have lower rates of depression than US-natives, but longitudinal assessments across multiple racial-ethnic groups are limited. This study examined the rates of prevalent, acquired, and persisting major depression and dysthymia by nativity and racial-ethnic origin while considering levels of acculturation, stress, and social ties. Data from the National Epidemiologic Survey on Alcohol and Related Conditions were used to model prevalence and 3-year incidence/persistence of major depression and dysthymia (DSM-IV diagnoses) using logistic regression. Substantive factors were assessed using standardized measures. The rates of major depression were lower for most immigrants, but differences were noted by race-ethnicity and outcome. Furthermore, immigrants had higher prevalence but not incidence of dysthymia. The associations between substantive factors and outcomes were mixed. This study describes and begins to explain immigrant trajectories of major depression and dysthymia over a 3-year period. The continuing research challenges and future directions are discussed.

Interactions between Depression and Facilitation within Neural Networks: Updating the Dual-Process Theory of Plasticity

PubMed Central

Prescott, Steven A.

1998-01-01

Repetitive stimulation often results in habituation of the elicited response. However, if the stimulus is sufficiently strong, habituation may be preceded by transient sensitization or even replaced by enduring sensitization. In 1970, Groves and Thompson formulated the dual-process theory of plasticity to explain these characteristic behavioral changes on the basis of competition between decremental plasticity (depression) and incremental plasticity (facilitation) occurring within the neural network. Data from both vertebrate and invertebrate systems are reviewed and indicate that the effects of depression and facilitation are not exclusively additive but, rather, that those processes interact in a complex manner. Serial ordering of induction of learning, in which a depressing locus precedes the modulatory system responsible for inducing facilitation, causes the facilitation to wane. The parallel and/or serial expression of depression and waning facilitation within the stimulus–response pathway culminates in the behavioral changes that characterize dual-process learning. A mathematical model is presented to formally express and extend understanding of the interactions between depression and facilitation. PMID:10489261

The interplay of loneliness and depressive symptoms across adolescence: exploring the role of personality traits.

PubMed

Vanhalst, Janne; Klimstra, Theo A; Luyckx, Koen; Scholte, Ron H J; Engels, Rutger C M E; Goossens, Luc

2012-06-01

Based on current theories of depression, reciprocal links between loneliness and depressive symptoms are expected to occur. However, longitudinal studies on adolescent samples are scarce and have yielded conflicting results. The present five-wave longitudinal study from mid- to late adolescence (N=428, M age at T1=15.22 years; 47% female) examined the direction of effect between loneliness and depressive symptoms, using cross-lagged path analysis. In addition, the robustness of these prospective associations was tested by examining the role of the Big Five personality traits (i.e., extraversion, conscientiousness, agreeableness, neuroticism, and openness) as explaining factors and moderators. Results indicated that loneliness and depressive symptoms influenced one another reciprocally, and these reciprocal associations were not attributable to their mutual overlap with personality traits. In addition, neuroticism was found to be a moderator, in that the bidirectional effects between loneliness and depressive symptoms were only found in adolescents high in neuroticism. Practical implications are discussed, and suggestions for future research are outlined.

Attachment Status Affects Heart Rate Responses to Experimental Ostracism in Inpatients with Depression

PubMed Central

De Rubeis, Jannika; Sütterlin, Stefan; Lange, Diane; Pawelzik, Markus; van Randenborgh, Annette; Victor, Daniela; Vögele, Claus

2016-01-01

Depression is assumed to be both a risk factor for rejection and a result of it, and as such constitutes an important factor in rejection research. Attachment theory has been applied to understand psychological disorders, such as depression, and can explain individual differences in responses to rejection. Research on autonomic nervous system activity to rejection experiences has been contradictory, with opposing strings of argumentation (activating vs. numbing). We investigated autonomic nervous system-mediated peripheral physiological responses (heart rate) to experimentally manipulated ostracism (Cyberball) in 97 depressed patients with organized (n = 52) and disorganized attachment status (n = 45). Controlling for baseline mean heart rate levels, depressed patients with disorganized attachment status responded to ostracism with significantly higher increases in heart rate than depressed patients with organized attachment status (p = .029; ηp2 = .051). These results suggest that attachment status may be a useful indicator of autonomic responses to perceived social threat, which in turn may affect the therapeutic process and the patient-therapist relationship. PMID:26943924

Oxytocin receptor gene and depressive symptoms associated with physiological reactivity to infant crying.

PubMed

Riem, Madelon M E; Pieper, Suzanne; Out, Dorothée; Bakermans-Kranenburg, Marian J; van Ijzendoorn, Marinus H

2011-06-01

Both the oxytocin receptor (OXTR) gene and depressive symptoms have been associated with parenting behaviour. The OXTR GG genotype has been suggested to be related to more sensitive parenting, whereas depressive symptoms may affect sensitivity negatively. We examined the role of OXTR and the influence of depressive symptoms in explaining differences in physiological reactivity to infant crying. Heart rate responses of 40 healthy females without children (age 19-47 years, randomly selected half of twin pairs) were measured during the presentation of three episodes of infant cry sounds. Participants with the presumably more efficient variant of the oxytonergic system gene (OXTR GG) had more pronounced physiological reactivity to repeated cry sounds, except when they showed more symptoms of depression. Results were replicated in the second half of the twin sample. This is the first study to suggest effects of OXTR genotype on physiological reactivity to infant crying. Depressive symptoms may however suppress the effect of the OXTR GG genotype.

Parenting Influences on Latino Children’s Social Competence in the First Grade: Parental Depression and Parent Involvement at Home and School

PubMed Central

Valdez, Carmen R.; Shewakramani, Vansa; Goldberg, Simon; Padilla, Brian

2013-01-01

Although it is widely accepted that parental depression is associated with problems with children’s socioemotional adjustment, the pathways by which parental depression influences children’s adjustment, particularly in low-income Latino children are not fully understood. In our investigation of 1,462 low-income Latino children in the first grade and their Spanish- and English-dominant parents, a factor analysis revealed three main pathways of possible influence of parent involvement in children’s social development: emotional involvement and educational involvement at home and at school. The findings from multigroup structural equation modeling revealed that whereas the first two pathways mediated the effect of parental depression on child social competence for Spanish-dominant parents, only emotional involvement explained parental depression effects for English-dominant parents. Parent educational involvement at school did not mediate parental depression effects for either Spanish- or English-dominant Latino parents. Discussion and implications of findings with respect to research, practice, and policy with Latinos follow. PMID:23325021

Parenting influences on Latino children's social competence in the first grade: parental depression and parent involvement at home and school.

PubMed

Valdez, Carmen R; Shewakramani, Vansa; Goldberg, Simon; Padilla, Brian

2013-10-01

Although it is widely accepted that parental depression is associated with problems with children's socioemotional adjustment, the pathways by which parental depression influences children's adjustment, particularly in low-income Latino children are not fully understood. In our investigation of 1,462 low-income Latino children in the first grade and their Spanish- and English-dominant parents, a factor analysis revealed three main pathways of possible influence of parent involvement in children's social development: emotional involvement and educational involvement at home and at school. The findings from multigroup structural equation modeling revealed that whereas the first two pathways mediated the effect of parental depression on child social competence for Spanish-dominant parents, only emotional involvement explained parental depression effects for English-dominant parents. Parent educational involvement at school did not mediate parental depression effects for either Spanish- or English-dominant Latino parents. Discussion and implications of findings with respect to research, practice, and policy with Latinos follow.

[Influence of childbirth experience and postpartum depression on quality of life in women after birth].

PubMed

Yeo, Jung Hee; Chun, Nami

2013-02-01

The purpose of this study was to identify influence of childbirth experience and postpartum depression on quality of life in women after birth. Two hundred and eleven postpartum women were asked to complete the questionnaires on their childbirth experience during their admission and on their postpartum depression and quality of life between one to three weeks after birth. Initial data were collected from February 1 to May 30, 2011 at two obstetric hospitals in Busan, Korea. Data were analyzed using t-test, ANOVA, Pearson correlation coefficients, and hierarchical multiple regression. The women's childbirth experience and postpartum depression were identified as factors influencing quality of life after birth. The model explained 50% of the variables. Results suggest that childbirth educators should include strategies to increase a positive childbirth experience and to decrease postpartum depression in their education programs in order to improve women's quality of life.

The price of soliciting and receiving negative feedback: self-verification theory as a vulnerability to depression theory.

PubMed

Joiner, T E

1995-05-01

The hypothesis that people who seek and receive negative feedback are vulnerable to increases in depressed symptoms was tested among 100 undergraduates and their roommates. Students and roommates completed questionnaires on their views of each other and on their own levels of negative feedback seeking, depressed and anxious symptoms, negative and positive affect, and self-esteem. Three weeks later, students and roommates completed the same questionnaires. Results were, in general, consistent with prediction. Students who reported an interest in their roommates' negative feedback and who lived with a roommate who viewed them negatively were at heightened risk for increases in depressed symptoms. These results could not be explained in terms of the variables' relations to trait self-esteem. The symptom specificity of the effect was moderately supported. Implications for work on interpersonal vulnerability to depression are discussed.

Perfectionism and depression among low-income chronically ill African American and White adolescents and their maternal parent.

PubMed

Rice, Kenneth G; Tucker, Carolyn M; Desmond, Frederic F

2008-09-01

Most research on perfectionism is based on convenience samples of university students or clinically distressed samples, and therefore relatively less is known about the development and implications of perfectionism for other groups. In this study, we examined perfectionism and depression in low-income African American (n = 39) and White (n = 55) adolescents with chronic illnesses (most with diabetes, asthma, and/or hypertension) and their primary parents. We specifically examined the association between parent and child perfectionism, and the link between perfectionism and depression in both groups. The African American adolescents reported significantly more maladaptive perfectionism than did the White adolescents, and the African American parents reported significantly higher scores on depression than did the White parents. Correlations and regression analyses revealed similarities and differences in perfectionism-depression associations that might be explained in light of cultural differences and the unique physical and emotional challenges faced by youth with chronic illnesses.

Induction of depressed mood: a test of opponent-process theory.

PubMed

Ranieri, D J; Zeiss, A M

1984-12-01

Solomon's (1980) opponent-process theory of acquired motivation has been used to explain many phenomena in which affective or hedonic contrasts appear to exist, but has not been applied to the induction of depressed mood. The purpose of this study, therefore, was to determine whether opponent-process theory can be applied to this area. Velten's (1968) mood-induction procedure was used and subjects were assigned either to a depression-induction condition or to one of two control groups. Self-report measures of depressed mood were taken before, during, and at several points after the mood induction. Results were not totally consistent with a rigorous set of criteria for supporting an opponent-process interpretation. This suggests that the opponent-process model may not be applicable to induced depressed mood. Possible weaknesses in the experimental design, along with implications for opponent-process theory, are discussed.

Physiological reactivity during autobiographical narratives in older adults: the roles of depression and anxiety.

PubMed

Robertson, Sarah M C; Swickert, Rhonda J; Connelly, Kathryn; Galizio, Ann

2015-01-01

Physiological reactivity (PR) describes the change in physiological functioning (e.g., heart rate, blood pressure, pulse pressure) that occurs after the induction of a stressful task. This study aims to understand the influence of mental health symptoms on patterns of PR during autobiographical narratives in an older adult sample. Eighty older adults completed self-report measures regarding their symptoms of depression and anxiety. Next, their blood pressure was recorded while they completed two verbal autobiographical narratives. During the positive narrative, anxiety was positively associated with increased PR while depression was negatively associated with PR. During the negative narrative, a significant interaction occurred whereby anxiety was significantly positively associated with PR for those participants low in depression. The above results are explained in the context of the Tripartite Model of Depression and Anxiety, which predicts different patterns of PR as a function of mental health symptoms. Limitations and future directions are also discussed.

Adaptation to Portuguese of the Depression, Anxiety and Stress Scales (DASS).

PubMed

Apóstolo, João Luís Alves; Mendes, Aida Cruz; Azeredo, Zaida Aguiar

2006-01-01

To adapt to Portuguese, of Portugal, the Depression, Anxiety and Stress Scales, a 21-item short scale (DASS 21), designed to measure depression, anxiety and stress. After translation and back-translation with the help of experts, the DASS 21 was administered to patients in external psychiatry consults (N=101), and its internal consistency, construct validity and concurrent validity were measured. The DASS 21 properties certify its quality to measure emotional states. The instrument reveals good internal consistency. Factorial analysis shows that the two-factor structure is more adequate. The first factor groups most of the items that theoretically assess anxiety and stress, and the second groups most of the items that assess depression, explaining, on the whole, 58.54% of total variance. The strong positive correlation between the DASS 21 and the Hospital Anxiety and Depression scale (HAD) confirms the hypothesis regarding the criterion validity, however, revealing fragilities as to the divergence between theoretically different constructs.

EXPLANATIONS FOR EDUCATION GRADIENTS IN DEPRESSION—THE CASE OF KOREA

PubMed Central

2013-01-01

Objectives We examine gender differences in educational gradients in depressive symptoms of married couples and identify what accounts for education gradients for husbands and wives. Methods We use a nationally representative sample of married couples from the 2006 Korean Longitudinal Study of Aging, which collected information about depressive symptoms and risk factors for both spouses. Results For married couples, we find significant education gradients in depressive symptoms for both husbands and wives. Economic resources, physical health, children, and the relationship of spouse explain educational gradients of both husbands and wives. On the other hand, work and organized social activities are important pathways for husbands, but not for wives. In contrast, spouse’s educational attainment accounts for wives’ educational gradient, but not husbands’. Conclusions Education is a strong predictor of depressive symptoms, but the pathways linking education to depressive symptoms differ between men and women. PMID:23645947

Parental divorce, parental depression, and gender differences in adult offspring suicide attempt.

PubMed

Lizardi, Dana; Thompson, Ronald G; Keyes, Katherine; Hasin, Deborah

2009-12-01

Research suggests parental divorce during childhood increases risk of suicide attempt for male but not female offspring. The negative impact on offspring associated with parental divorce may be better explained by parental psychopathology, such as depression. We examined whether adult offspring of parental divorce experience elevated risk of suicide attempt, controlling for parental history of depression, and whether the risk varies by the gender of the offspring. Using the 2001 to 2002 National Epidemiologic Survey on Alcohol and Related Conditions (NESARC), the sample consists of respondents who experienced parental divorce (N = 4895). Multivariable regressions controlled for age, race/ethnicity, income, marital status, and parental history of depression. Females living with their fathers were significantly more likely to report lifetime suicide attempts than females living with their mothers, even after controlling for parental depression. Findings suggest that childhood/adolescent parental divorce may have a stronger impact on suicide attempt risk in female offspring than previously recognized.

The Relationship Between Problem-Solving Ability and Self-Harm Amongst People with Mild Intellectual Disabilities.

PubMed

Rees, Joanna; Langdon, Peter E

2016-07-01

The purpose of this study was to investigate the relationship between depression, hopelessness, problem-solving ability and self-harming behaviours amongst people with mild intellectual disabilities (IDs). Thirty-six people with mild IDs (77.9% women, Mage  = 31.77, SD = 10.73, MIQ  = 62.65, SD = 5.74) who had a history of self-harm were recruited. Participants were asked to complete measures of depression, hopelessness and problem-solving ability. Cutting was most frequently observed, and depression was prevalent amongst the sample. There was a significant positive relationship between depression and hopelessness, while there was no significant relationship between self-harm and depression or hopelessness. Problem-solving ability explained 15% of the variance in self-harm scores. Problem-solving ability appears to be associated with self-harming behaviours in people with mild IDs. © 2015 John Wiley & Sons Ltd.

Positive affect promotes well-being and alleviates depression: The mediating effect of attentional bias.

PubMed

Xu, Yuanyuan; Yu, Yongju; Xie, Yuanjun; Peng, Li; Liu, Botao; Xie, Junrun; Bian, Chen; Li, Min

2015-08-30

The present study tested whether the relationships among positive affect, psychological well-being, life satisfaction and depression could be explained by positive and negative attentional bias. Structural equation modeling and mediation analyses were conducted based on 565 medical freshmen in China. The model of attentional bias as a mediator between positive affect promoting well-being and decreasing depression fit the data. Finding showed positive affect significantly related to positive and negative attentional biases. People who had higher level of positive affect held more positive attentional bias and less negative attentional bias, and reported higher levels of psychological well-being, life satisfaction and lower levels of depression. The utility of the attentional bias as the mechanism through which positive affect enhances well-being and alleviates depression was supported. Applications in cultivating positive affect and regulating attentional bias in counseling and education are discussed. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Understanding climate impacts on vegetation using a spatiotemporal non-linear Granger causality framework

NASA Astrophysics Data System (ADS)

Papagiannopoulou, Christina; Decubber, Stijn; Miralles, Diego; Demuzere, Matthias; Dorigo, Wouter; Verhoest, Niko; Waegeman, Willem

2017-04-01

Satellite data provide an abundance of information about crucial climatic and environmental variables. These data - consisting of global records, spanning up to 35 years and having the form of multivariate time series with different spatial and temporal resolutions - enable the study of key climate-vegetation interactions. Although methods which are based on correlations and linear models are typically used for this purpose, their assumptions for linearity about the climate-vegetation relationships are too simplistic. Therefore, we adopt a recently proposed non-linear Granger causality analysis [1], in which we incorporate spatial information, concatenating data from neighboring pixels and training a joint model on the combined data. Experimental results based on global data sets show that considering non-linear relationships leads to a higher explained variance of past vegetation dynamics, compared to simple linear models. Our approach consists of several steps. First, we compile an extensive database [1], which includes multiple data sets for land surface temperature, near-surface air temperature, surface radiation, precipitation, snow water equivalents and surface soil moisture. Based on this database, high-level features are constructed and considered as predictors in our machine-learning framework. These high-level features include (de-trended) seasonal anomalies, lagged variables, past cumulative variables, and extreme indices, all calculated based on the raw climatic data. Second, we apply a spatiotemporal non-linear Granger causality framework - in which the linear predictive model is substituted for a non-linear machine learning algorithm - in order to assess which of these predictor variables Granger-cause vegetation dynamics at each 1° pixel. We use the de-trended anomalies of Normalized Difference Vegetation Index (NDVI) to characterize vegetation, being the target variable of our framework. Experimental results indicate that climate strongly (Granger-)causes vegetation dynamics in most regions globally. More specifically, water availability is the most dominant vegetation driver, being the dominant vegetation driver in 54% of the vegetated surface. Furthermore, our results show that precipitation and soil moisture have prolonged impacts on vegetation in semiarid regions, with up to 10% of additional explained variance on the vegetation dynamics occurring three months later. Finally, hydro-climatic extremes seem to have a remarkable impact on vegetation, since they also explain up to 10% of additional variance of vegetation in certain regions despite their infrequent occurrence. References [1] Papagiannopoulou, C., Miralles, D. G., Verhoest, N. E. C., Dorigo, W. A., and Waegeman, W.: A non-linear Granger causality framework to investigate climate-vegetation dynamics, Geosci. Model Dev. Discuss., doi:10.5194/gmd-2016-266, in review, 2016.

Optical Random Riemann Waves in Integrable Turbulence

NASA Astrophysics Data System (ADS)

Randoux, Stéphane; Gustave, François; Suret, Pierre; El, Gennady

2017-06-01

We examine integrable turbulence (IT) in the framework of the defocusing cubic one-dimensional nonlinear Schrödinger equation. This is done theoretically and experimentally, by realizing an optical fiber experiment in which the defocusing Kerr nonlinearity strongly dominates linear dispersive effects. Using a dispersive-hydrodynamic approach, we show that the development of IT can be divided into two distinct stages, the initial, prebreaking stage being described by a system of interacting random Riemann waves. We explain the low-tailed statistics of the wave intensity in IT and show that the Riemann invariants of the asymptotic nonlinear geometric optics system represent the observable quantities that provide new insight into statistical features of the initial stage of the IT development by exhibiting stationary probability density functions.

Nonlinear dynamics of a two-dimensional Wigner solid on superfluid helium

NASA Astrophysics Data System (ADS)

Monarkha, Yu. P.

2018-04-01

Nonlinear dynamics and transport properties of a 2D Wigner solid (WS) on the free surface of superfluid helium are theoretically studied. The analysis is nonperturbative in the amplitude of the WS velocity. An anomalous nonlinear response of the liquid helium surface to the oscillating motion of the WS is shown to appear when the driving frequency is close to subharmonics of the frequency of a capillary wave (ripplon) whose wave vector coincides with a reciprocal-lattice vector. As a result, the effective mass of surface dimples formed under electrons and the kinetic friction acquire sharp anomalies in the low-frequency range, which affects the mobility and magnetoconductivity of the WS. The results obtained here explain a variety of experimental observations reported previously.

Possible limitations of the classical model of orientational optical nonlinearity in nematics

NASA Astrophysics Data System (ADS)

Sierakowski, Marek; Teterycz, Małgorzata

2008-09-01

Orientational nonlinearity is the major mechanism of nonlinear optical phenomena observed in liquidcrystalline phase while it does not appear to such extent in any other materials. It is caused by distortion of initial molecular arrangement of an anisotropic medium induced by optical field. Deformation of the anisotropic structure means spatial changes of refractive index of the medium. This effect has been studied in earnest since the 1980s as its application became more apparent. In this paper, some results of experimental examination of molecular reorientation in nematics by optical field are presented, which are not explained in frame of existing Oseen-Frank model and Erickson-Leslie continuous theory. Possible reasons of this discordance are considered and a way of explanation is suggested.

On neural networks in identification and control of dynamic systems

NASA Technical Reports Server (NTRS)

Phan, Minh; Juang, Jer-Nan; Hyland, David C.

1993-01-01

This paper presents a discussion of the applicability of neural networks in the identification and control of dynamic systems. Emphasis is placed on the understanding of how the neural networks handle linear systems and how the new approach is related to conventional system identification and control methods. Extensions of the approach to nonlinear systems are then made. The paper explains the fundamental concepts of neural networks in their simplest terms. Among the topics discussed are feed forward and recurrent networks in relation to the standard state-space and observer models, linear and nonlinear auto-regressive models, linear, predictors, one-step ahead control, and model reference adaptive control for linear and nonlinear systems. Numerical examples are presented to illustrate the application of these important concepts.

Experimental investigation of the effect of pump incoherence on nonlinear pump spectral broadening and continuous-wave supercontinuum generation

NASA Astrophysics Data System (ADS)

Martin-Lopez, S.; Carrasco-Sanz, A.; Corredera, P.; Abrardi, L.; Hernanz, M. L.; Gonzalez-Herraez, M.

2006-12-01

The development of high-power cw fiber lasers has triggered a great interest in the phenomena of nonlinear pump spectral broadening and cw supercontinuum generation. These effects have very convenient applications in Raman amplification, optical fiber metrology, and fiber sensing. In particular, it was recently shown that pump incoherence has a strong impact in these processes. We study experimentally the effect of pump incoherence in nonlinear pump spectral broadening and cw supercontinuum generation in optical fibers. We show that under certain experimental conditions an optimum degree of pump incoherence yields the best performance in the broadening process. We qualitatively explain these results, and we point out that these results may have important implications in cw supercontinuum optimization.

Testing Components of a Self-Management Theory in Adolescents With Type 1 Diabetes Mellitus.

PubMed

Verchota, Gwen; Sawin, Kathleen J

The role of self-management in adolescents with type 1 diabetes mellitus is not well understood. The purpose of the research was to examine the relationship of key individual and family self-management theory, context, and process variables on proximal (self-management behaviors) and distal (hemoglobin A1c and diabetes-specific health-related quality of life) outcomes in adolescents with type 1 diabetes. A correlational, cross-sectional study was conducted to identify factors contributing to outcomes in adolescents with Type 1 diabetes and examine potential relationships between context, process, and outcome variables delineated in individual and family self-management theory. Participants were 103 adolescent-parent dyads (adolescents ages 12-17) with Type 1 diabetes from a Midwest, outpatient, diabetes clinic. The dyads completed a self-report survey including instruments intended to measure context, process, and outcome variables from individual and family self-management theory. Using hierarchical multiple regression, context (depressive symptoms) and process (communication) variables explained 37% of the variance in self-management behaviors. Regimen complexity-the only significant predictor-explained 11% of the variance in hemoglobin A1c. Neither process variables nor self-management behaviors were significant. For the diabetes-specific health-related quality of life outcome, context (regimen complexity and depressive symptoms) explained 26% of the variance at step 1; an additional 9% of the variance was explained when process (self-efficacy and communication) variables were added at step 2; and 52% of the variance was explained when self-management behaviors were added at Step 3. In the final model, three variables were significant predictors: depressive symptoms, self-efficacy, and self-management behaviors. The individual and family self-management theory can serve as a cogent theory for understanding key concepts, processes, and outcomes essential to self-management in adolescents and families dealing with Type 1 diabetes mellitus.

Gonadal hormone levels and platelet tryptophan and serotonin concentrations in perimenopausal women with or without depressive symptoms.

PubMed

Flores-Ramos, Mónica; Moreno, Julia; Heinze, Gerhard; Aguilera-Pérez, Rafael; Pellicer Graham, Francisco

2014-03-01

The etiology of depressive symptoms associated with the transition to menopause is still unknown; hormonal changes, serotonergic system or insomnia, could be a trigger to depressive symptomatology. The aim of the present study was to evaluate gonadal hormonal levels, platelet serotonin concentrations and platelet tryptophan concentrations in a group of depressed perimenopausal women and their healthy counterparts. A total of 63 perimenopausal women between 45 and 55 years old were evaluated; of these, 44 were depressed patients, and 19 were perimenopausal women without depression. The instruments that were applied included the Center for Epidemiologic Studies Depression Scale (CES-D), the Hamilton Depression Rating Scale (HDRS) and the Green Climacteric Scale (GCS); gonadal hormone levels and platelet tryptophan and serotonin concentrations were measured in all participants. Differences in hormonal levels and tryptophan and serotonin concentrations were evaluated with respect to specific symptoms, such as insomnia, hot flashes, nervousness, depressed mood and loss of interest. No differences between groups were observed with respect to hormonal levels and tryptophan and serotonin concentrations; mean sleep hours and insomnia were significantly correlated with platelet tryptophan concentrations. In this sample, all symptoms of depression could not be explained by platelet tryptophan and serotonin concentrations and hormonal levels; differences were observed only when we evaluated insomnia and hot flashes.

Parenting intervention effects on parental depressive symptoms: examining the role of parenting and child behavior.

PubMed

Wong, Jessie J; Gonzales, Nancy A; Montaño, Zorash; Dumka, Larry; Millsap, Roger E

2014-06-01

Parental depression is a major risk factor in child development. Growing research suggests parenting programs can positively impact parental depressive symptoms, although the specific mechanisms that explain these effects are unknown. The current study examined parenting mediated effects of a parenting program on mothers' and fathers' depressive symptoms, as well as the role of child behavior in linking parenting to reductions in depressive symptoms. The study samples included 494 mothers and 288 fathers of Mexican origin adolescents who participated in a randomized trial of the Bridges to High School Program/Proyecto Puentes a la Secundaria, a universal prevention and promotion intervention that included parent training but did not directly target parental depressive symptoms. Parenting mediator models tested program effects on parental depressive symptoms through changes in harsh and supportive parenting. Results showed a significant indirect intervention effect on maternal depressive symptoms through changes in mothers' harsh parenting. Next, child behavior models revealed a partial mediation effect of harsh parenting and a full mediation effect of supportive parenting on maternal depressive symptoms through mothers' reports of child externalizing symptoms. Indirect effects of fathers' harsh and supportive parenting on paternal depressive symptoms were also found through fathers' reports of child behavior. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Does caregiver well-being predict stroke survivor depressive symptoms? A mediation analysis.

PubMed

Grant, Joan S; Clay, Olivio J; Keltner, Norman L; Haley, William E; Wadley, Virginia G; Perkins, Martinique M; Roth, David L

2013-01-01

Studies suggest that family caregiver well-being (ie, depressive symptoms and life satisfaction) may affect stroke survivor depressive symptoms. We used mediation analysis to assess whether caregiver well-being might be a factor explaining stroke survivor depressive symptoms, after controlling for demographic factors and stroke survivor impairments and problems. Caregiver/stroke participant dyads (N = 146) completed measures of stroke survivor impairments and problems and depressive symptoms and caregiver depressive symptoms and life satisfaction. Mediation analysis was used to examine whether caregiver well-being mediated the relationship between stroke survivor impairments and problems and stroke survivor depressive symptoms. As expected, more stroke survivor problems and impairments were associated with higher levels of stroke survivor depressive symptoms (P < .0001). After controlling for demographic factors, we found that this relationship was partially mediated by caregiver life satisfaction (29.29%) and caregiver depressive symptoms (32.95%). Although these measures combined to account for 40.50% of the relationship between survivor problems and impairments and depressive symptoms, the direct effect remained significant. Findings indicate that stroke survivor impairments and problems may affect family caregivers and stroke survivors and a high level of caregiver distress may result in poorer outcomes for stroke survivors. Results highlight the likely importance of intervening with both stroke survivors and family caregivers to optimize recovery after stroke.

Women's experiences of health visitor delivered listening visits as a treatment for postnatal depression: a qualitative study.

PubMed

Turner, Katrina M; Chew-Graham, Carolyn; Folkes, Liz; Sharp, Deborah

2010-02-01

To explore women's experiences of health visitor delivered listening visits as a treatment for postnatal depression. In-depth interviews with 22 women who had received listening visits as a treatment for postnatal depression. All the women reported the visits as beneficial, although many of them had required additional intervention to manage their symptoms. Women who had a previous history of depression and women whose depression was not attributed to events in the postnatal period perceived the listening visits to be less beneficial. Receiving visits from a research health visitor, rather than their practice health visitor, was felt to be advantageous. Women with postnatal depression may report listening visits as helpful but insufficient to manage their depression. The extent to which women report listening visits as beneficial appears to be linked to the causes of their depression, the way in which the visits are delivered and by whom. Practitioners managing women with postnatal depression should discuss possible causes and previous episodes of depression before suggesting listening visits as a treatment. They need to explain what the visits will entail, ensure that additional types of treatment remain available and encourage women to utilise other forms of support. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.

The need for cognition mediates and moderates the association between depressive symptoms and impaired effortful control.

PubMed

Nishiguchi, Yuki; Takano, Keisuke; Tanno, Yoshihiko

2016-07-30

Previous studies have shown a negative correlation between effortful control (EC) and depressive symptoms. EC is defined as the efficiency of executive attention, which may be reduced by the attentional impairment associated with depression. However, the mechanism underlying this correlation is still unclear. We investigated the relationship between EC and depressive symptoms with the hypothesis that cognitive motivation, or need for cognition (NfC), is a possible mediator of this relationship. Participants were 178 Japanese university students. Each completed the Zung Self-Rating Depression Scale, Effortful Control Scale, and Need for Cognition Scale at baseline and follow-up assessments. Supporting our hypothesis, mediation analyses revealed a significant indirect effect of depressive symptoms on EC that was mediated by NfC. In addition, our data demonstrated a direct effect of depressive symptoms on EC. Longitudinal analysis indicated that an increase in depression and a decrease in NfC occurred synchronously, while NfC predicted an increase in EC over time. Depressive symptoms may decrease executive functioning and effortful control both directly and indirectly, the latter effect being mediated by motivation. These findings imply that a motivational deficit may partially explain the decreased EC found in people suffering from depression. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

New Treatment Strategies of Depression: Based on Mechanisms Related to Neuroplasticity

PubMed Central

Lane, Hsien-Yuan

2017-01-01

Major depressive disorder is a severe and complex mental disorder. Impaired neurotransmission and disrupted signalling pathways may influence neuroplasticity, which is involved in the brain dysfunction in depression. Traditional neurobiological theories of depression, such as monoamine hypothesis, cannot fully explain the whole picture of depressive disorders. In this review, we discussed new treatment directions of depression, including modulation of glutamatergic system and noninvasive brain stimulation. Dysfunction of glutamatergic neurotransmission plays an important role in the pathophysiology of depression. Ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, has rapid and lasting antidepressive effects in previous studies. In addition to ketamine, other glutamatergic modulators, such as sarcosine, also show potential antidepressant effect in animal models or clinical trials. Noninvasive brain stimulation is another new treatment strategy beyond pharmacotherapy. Growing evidence has demonstrated that superficial brain stimulations, such as transcranial magnetic stimulation, transcranial direct current stimulation, cranial electrotherapy stimulation, and magnetic seizure therapy, can improve depressive symptoms. The antidepressive effect of these brain stimulations may be through modulating neuroplasticity. In conclusion, drugs that modulate neurotransmission via NMDA receptor and noninvasive brain stimulation may provide new directions of treatment for depression. Furthermore, exploring the underlying mechanisms will help in developing novel therapies for depression in the future. PMID:28491480

Cognitive bias in back pain patients attending osteopathy: testing the enmeshment model in reference to future thinking.

PubMed

Read, Jessica; Pincus, Tamar

2004-12-01

Depressive symptoms are common in chronic pain. Previous research has found differences in information-processing biases in depressed pain patients and depressed people without pain. The schema enmeshment model of pain (SEMP) has been proposed to explain chronic pain patients' information-processing biases. Negative future thinking is common in depression but has not been explored in relation to chronic pain and information-processing models. The study aimed to test the SEMP with reference to future thinking. An information-processing paradigm compared endorsement and recall bias between depressed and non-depressed chronic low back pain patients and control participants. Twenty-five depressed and 35 non-depressed chronic low back pain patients and 25 control participants (student osteopaths) were recruited from an osteopathy practice. Participants were asked to endorse positive and negative ill-health, depression-related, and neutral (control) adjectives, encoded in reference to either current or future time-frame. Incidental recall of the adjectives was then tested. While the expected hypothesis of a recall bias by depressed pain patients towards ill-health stimuli in the current condition was confirmed, the recall bias was not present in the future condition. Additionally, patterns of endorsement and recall bias differed. Results extend understanding of future thinking in chronic pain within the context of the SEMP.

Immune and hormonal activity in adults suffering from depression.

PubMed

Nunes, S O V; Reiche, E M V; Morimoto, H K; Matsuo, T; Itano, E N; Xavier, E C D; Yamashita, C M; Vieira, V R; Menoli, A V; Silva, S S; Costa, F B; Reiche, F V; Silva, F L V; Kaminami, M S

2002-05-01

An association between depression and altered immune and hormonal systems has been suggested by the results of many studies. In the present study we carried out immune and hormonal measurements in 40 non-medicated, ambulatory adult patients with depression determined by CID-10 criteria and compared with 34 healthy nondepressed subjects. The severity of the condition was determined with the Hamilton Depression Rating Scale. Of 40 depressed patients, 31 had very severe and 9 severe or moderate depression, 29 (72.5%) were females and 11 (27.5%) were males (2.6:1 ratio). The results revealed a significant reduction of albumin and elevation of alpha-1, alpha-2 and beta-globulins, and soluble IL-2 receptor in patients with depression compared to the values obtained for nondepressed subjects (P<0.05). The decrease lymphocyte proliferation in response to a mitogen was significantly lower in severely or moderately depressed patients when compared to control (P<0.05). These data confirm the immunological disturbance of acute phase proteins and cellular immune response in patients with depression. Other results may be explained by a variety of interacting factors such as number of patients, age, sex, and the nature, severity and/or duration of depression. Thus, the data obtained should be interpreted with caution and the precise clinical relevance of these findings requires further investigation.

The role of neuroinflammation and neurovascular dysfunction in major depressive disorder.

PubMed

Jeon, Sang Won; Kim, Yong-Ku

2018-01-01

Although depression has generally been explained with monoamine theory, it is far more multifactorial, and therapies that address the disease's pathway have not been developed. In this context, an understanding of neuroinflammation and neurovascular dysfunction would enable a more comprehensive approach to depression. Inflammation is in a sense a type of allostatic load involving the immune, endocrine, and nervous systems. Neuroinflammation is involved in the pathophysiology of depression by increasing proinflammatory cytokines, activating the hypothalamus-pituitary-adrenal axis, increasing glucocorticoid resistance, and affecting serotonin synthesis and metabolism, neuronal apoptosis and neurogenesis, and neuroplasticity. In future, identifying the subtypes of depression with increased vulnerability to inflammation and testing the effects of inflammatory modulating agents in these patient groups through clinical trials will lead to more concrete conclusions on the matter. The vascular depression hypothesis is supported by evidence for the association between vascular disease and late-onset depression and between ischemic brain lesions and distinctive depressive symptoms. Vascular depression may be the entity most suitable for studies of the mechanisms of depression. Pharmacotherapies used in the prevention and treatment of cerebrovascular disease may help prevent vascular depression. In future, developments in structural and functional imaging, electrophysiology, chronobiology, and genetics will reveal the association between depression and brain lesions. This article aims to give a general review of the existing issues examined in the literature pertaining to depression-related neuroinflammatory and vascular functions, related pathophysiology, applicability to depression treatment, and directions for future research.

The role of neuroinflammation and neurovascular dysfunction in major depressive disorder

PubMed Central

Jeon, Sang Won; Kim, Yong-Ku

2018-01-01

Although depression has generally been explained with monoamine theory, it is far more multifactorial, and therapies that address the disease’s pathway have not been developed. In this context, an understanding of neuroinflammation and neurovascular dysfunction would enable a more comprehensive approach to depression. Inflammation is in a sense a type of allostatic load involving the immune, endocrine, and nervous systems. Neuroinflammation is involved in the pathophysiology of depression by increasing proinflammatory cytokines, activating the hypothalamus–pituitary–adrenal axis, increasing glucocorticoid resistance, and affecting serotonin synthesis and metabolism, neuronal apoptosis and neurogenesis, and neuroplasticity. In future, identifying the subtypes of depression with increased vulnerability to inflammation and testing the effects of inflammatory modulating agents in these patient groups through clinical trials will lead to more concrete conclusions on the matter. The vascular depression hypothesis is supported by evidence for the association between vascular disease and late-onset depression and between ischemic brain lesions and distinctive depressive symptoms. Vascular depression may be the entity most suitable for studies of the mechanisms of depression. Pharmacotherapies used in the prevention and treatment of cerebrovascular disease may help prevent vascular depression. In future, developments in structural and functional imaging, electrophysiology, chronobiology, and genetics will reveal the association between depression and brain lesions. This article aims to give a general review of the existing issues examined in the literature pertaining to depression-related neuroinflammatory and vascular functions, related pathophysiology, applicability to depression treatment, and directions for future research. PMID:29773951

Does reverse causality explain the relationship between diet and depression?

PubMed

Jacka, Felice N; Cherbuin, Nicolas; Anstey, Kaarin J; Butterworth, Peter

2015-04-01

Observational studies have repeatedly demonstrated relationships between habitual diet quality and depression. However, whilst reverse causality has not been the identified mechanism for these associations in prospective studies, the relationship between diet and depression is likely complex and bidirectional. Thus explicit investigation of the reverse causality hypothesis is warranted. Data were drawn from the Personality and Total Health (PATH) Through Life Study, a longitudinal community survey following three age cohorts from Australia. Analyses evaluated the relationships between past depression and treatment, current depressive symptoms and dietary patterns. Individuals with current depression had lower scores on a healthy dietary pattern; however, those who had been previously depressed and sought treatment had higher scores on the healthy dietary pattern at the later baseline assessment. Moreover, those who had reported prior, but not current, depression also had lower scores on the western dietary pattern than those without prior depression, regardless of whether they had been previously treated for their symptoms. Self-report data and possible recall bias limit our conclusions. In this study, prior depression was associated with better quality diets at the later time point. Thus, while current depression is associated with poorer dietary habits, a history of depression may prompt healthier dietary behaviours in the long term. Given the demonstrated relationships between diet quality and depressive illness, clinicians should advocate dietary improvement for their patients with depression and should not be pessimistic about the likelihood of adherence to such recommendations. Copyright © 2015 Elsevier B.V. All rights reserved.

We should be using nonlinear indices when relating heart-rate dynamics to cognition and mood

PubMed Central

Young, Hayley; Benton, David

2015-01-01

Both heart rate (HR) and brain functioning involve the integrated output of a multitude of regulatory mechanisms, that are not quantified adequately by linear approximations such as means and standard deviations. It was therefore considered whether non-linear measures of HR complexity are more strongly associated with cognition and mood. Whilst resting, the inter-beat (R-R) time series of twenty-one males and twenty-four females were measured for five minutes. The data were summarised using time, frequency and nonlinear complexity measures. Attention, memory, reaction times, mood and cortisol levels were assessed. Nonlinear HR indices captured additional information, enabling a greater percentage of the variance in behaviour to be explained. On occasions non-linear indices were related to aspects for behaviour, for example focused attention and cortisol production, when time or frequency indices were not. These effects were sexually dimorphic with HR complexity being more strongly associated with the behaviour of females. It was concluded that nonlinear rather than linear methods of summarizing the HR times series offers a novel way of relating brain functioning and behaviour. It should be considered whether non-linear measures of HR complexity can be used as a biomarker of the integrated functioning of the brain. PMID:26565560

Chaos theory for clinical manifestations in multiple sclerosis.

PubMed

Akaishi, Tetsuya; Takahashi, Toshiyuki; Nakashima, Ichiro

2018-06-01

Multiple sclerosis (MS) is a demyelinating disease which characteristically shows repeated relapses and remissions irregularly in the central nervous system. At present, the pathological mechanism of MS is unknown and we do not have any theories or mathematical models to explain its disseminated patterns in time and space. In this paper, we present a new theoretical model from a viewpoint of complex system with chaos model to reproduce and explain the non-linear clinical and pathological manifestations in MS. First, we adopted a discrete logistic equation with non-linear dynamics to prepare a scalar quantity for the strength of pathogenic factor at a specific location of the central nervous system at a specific time to reflect the negative feedback in immunity. Then, we set distinct minimum thresholds in the above-mentioned scalar quantity for demyelination possibly causing clinical relapses and for cerebral atrophy. With this simple model, we could theoretically reproduce all the subtypes of relapsing-remitting MS, primary progressive MS, and secondary progressive MS. With the sensitivity to initial conditions and sensitivity to minute change in parameters of the chaos theory, we could also reproduce the spatial dissemination. Such chaotic behavior could be reproduced with other similar upward-convex functions with appropriate set of initial conditions and parameters. In conclusion, by applying chaos theory to the three-dimensional scalar field of the central nervous system, we can reproduce the non-linear outcome of the clinical course and explain the unsolved disseminations in time and space of the MS patients. Copyright © 2018 Elsevier Ltd. All rights reserved.

Cognitive Performance in Suicidal Depressed Elderly: Preliminary Report

PubMed Central

Dombrovski, Alexandre Y.; Butters, Meryl A.; Reynolds, Charles F.; Houck, Patricia R.; Clark, Luke; Mazumdar, Sati; Szanto, Katalin

2009-01-01

Objective Deficits in executive functions may play an important role in late-life suicide; however the association is understudied. This study examined cognitive function in general and executive functioning specifically in depressed elderly with and without suicidal ideation and attempts. Design Case-control study. Setting University-affiliated psychiatric hospital. Participants We compared 32 suicidal depressed participants aged 60 and older with 32 non-suicidal depressed participants equated for age, education, and gender. Measurements We assessed global cognitive function and executive function with the Dementia Rating Scale (DRS) and the Executive Interview (EXIT25), respectively. Results Suicidal and non-suicidal depressed groups were comparable in terms of severity of depression and burden of physical illness. Suicidal participants performed worse on the EXIT25, and on the DRS total scale, as well as on Memory and Attention subscales. The differences were not explained by the presence of dementia, substance use, medication exposure, or brain injury from suicide attempts. Conclusions Poor performance on tests of executive function, attention, and memory is associated with suicidal behavior in late-life depression. PMID:18239196

[Depressive realism: happiness or objectivity].

PubMed

Birinci, Fatih; Dirik, Gülay

2010-01-01

Realism is described as objective evaluations and judgments about the world; however, some research indicates that judgments made by "normal" people include a self-favored, positive bias in the perception of reality. Additionally, some studies report that compared to normal people, such cognitive distortions are less likely among depressive people. These findings gave rise to the depressive realism hypothesis. While results of several studies verify the notion that depressive people evaluate reality more objectively, other studies fail to support this hypothesis. Several causes for these inconsistent findings have been proposed, which can be characterized under 3 headings. One proposed explanation suggests that what is accepted as "realistic" in these studies is not quite objective and is in fact ambiguous. According to another perspective, the term "depressive" used in these studies is inconsistent with the criteria of scientific diagnostic methods. Another suggests that the research results can only be obtained under the specific experimental conditions. General negativity and limited processing are popular approaches used for explaining the depressive realism hypothesis. Nowadays, the debate over this hypothesis continues. The present review focuses on frequently cited research related to depressive realism and discusses the findings.

[Depression in children at the beginning of school education. Prevalence of the phenomenon and its relation to the child's adaptive capacity].

PubMed

Bomba, J; Jaklewicz, H

1990-01-01

Depression in children has an unfavourable influence on the psychosocial development of the individual, therefore it requires suitable therapeutic and prophylactic approach. The dependencies between school-age immaturity and the prevalence of depression in children were evaluated in the prospective study. The school maturity, and one year later the prevalence of depression were studied in a representative sample of 502 "0"-grade children from the large urban population. The school immaturity was found in 10.56% of probands. More common symptoms were: withdrawal and antisocial behaviour. Depression was found in 32.79% of first-grade students, more frequent children with adaptation difficulties, especially among school-immature boys. The premature biological development, the symptoms of organic brain damage, and low I.Q. do not explain sufficiently neither the school-immaturity nor the prevalence of depression in children. It was found that emotional and social immaturity to the school duties facilitates the onset of depression among I grade students, while the role of the family and school in the genesis of both phenomena studied requires further investigations.

The role of neuroticism and extraversion in the stress-anxiety and stress-depression relationships.

PubMed

Uliaszek, Amanda A; Zinbarg, Richard E; Mineka, Susan; Craske, Michelle G; Sutton, Jonathan M; Griffith, James W; Rose, Raphael; Waters, Allison; Hammen, Constance

2010-07-01

Though there is a considerable amount of research supporting the association between stressful life events and major depression, there is a paucity of research concerning a range of other life stress constructs, non-depressive disorders, the role of stable personality traits, and gender differences. This study addresses these deficits by: (a) focusing on the association between interpersonal and non-interpersonal chronic life stress (CLS) and both depressive and anxiety disorders; (b) examining the roles of neuroticism and low extraversion in these associations; and (c) assessing gender differences. Participants were 603 adolescents from a study examining risk factors for emotional disorders. Depression and social phobia were associated with interpersonal CLS (IP-CLS), with neuroticism partially accounting for these associations. Low extraversion partially accounted for the association between social phobia and IP-CLS. Depression was also associated with non-interpersonal CLS (NI-CLS), but only in females. This study provides preliminary evidence for the importance of personality variables in explaining shared associations between stress and depression. Additionally, the stress-social phobia relationship is highlighted with no evidence supporting an association between other anxiety disorders and CLS.

Parametric and nonparametric Granger causality testing: Linkages between international stock markets

NASA Astrophysics Data System (ADS)

De Gooijer, Jan G.; Sivarajasingham, Selliah

2008-04-01

This study investigates long-term linear and nonlinear causal linkages among eleven stock markets, six industrialized markets and five emerging markets of South-East Asia. We cover the period 1987-2006, taking into account the on-set of the Asian financial crisis of 1997. We first apply a test for the presence of general nonlinearity in vector time series. Substantial differences exist between the pre- and post-crisis period in terms of the total number of significant nonlinear relationships. We then examine both periods, using a new nonparametric test for Granger noncausality and the conventional parametric Granger noncausality test. One major finding is that the Asian stock markets have become more internationally integrated after the Asian financial crisis. An exception is the Sri Lankan market with almost no significant long-term linear and nonlinear causal linkages with other markets. To ensure that any causality is strictly nonlinear in nature, we also examine the nonlinear causal relationships of VAR filtered residuals and VAR filtered squared residuals for the post-crisis sample. We find quite a few remaining significant bi- and uni-directional causal nonlinear relationships in these series. Finally, after filtering the VAR-residuals with GARCH-BEKK models, we show that the nonparametric test statistics are substantially smaller in both magnitude and statistical significance than those before filtering. This indicates that nonlinear causality can, to a large extent, be explained by simple volatility effects.

Non-Linear Approach in Kinesiology Should Be Preferred to the Linear--A Case of Basketball.

PubMed

Trninić, Marko; Jeličić, Mario; Papić, Vladan

2015-07-01

In kinesiology, medicine, biology and psychology, in which research focus is on dynamical self-organized systems, complex connections exist between variables. Non-linear nature of complex systems has been discussed and explained by the example of non-linear anthropometric predictors of performance in basketball. Previous studies interpreted relations between anthropometric features and measures of effectiveness in basketball by (a) using linear correlation models, and by (b) including all basketball athletes in the same sample of participants regardless of their playing position. In this paper the significance and character of linear and non-linear relations between simple anthropometric predictors (AP) and performance criteria consisting of situation-related measures of effectiveness (SE) in basketball were determined and evaluated. The sample of participants consisted of top-level junior basketball players divided in three groups according to their playing time (8 minutes and more per game) and playing position: guards (N = 42), forwards (N = 26) and centers (N = 40). Linear (general model) and non-linear (general model) regression models were calculated simultaneously and separately for each group. The conclusion is viable: non-linear regressions are frequently superior to linear correlations when interpreting actual association logic among research variables.

Stable scalable control of soliton propagation in broadband nonlinear optical waveguides

NASA Astrophysics Data System (ADS)

Peleg, Avner; Nguyen, Quan M.; Huynh, Toan T.

2017-02-01

We develop a method for achieving scalable transmission stabilization and switching of N colliding soliton sequences in optical waveguides with broadband delayed Raman response and narrowband nonlinear gain-loss. We show that dynamics of soliton amplitudes in N-sequence transmission is described by a generalized N-dimensional predator-prey model. Stability and bifurcation analysis for the predator-prey model are used to obtain simple conditions on the physical parameters for robust transmission stabilization as well as on-off and off-on switching of M out of N soliton sequences. Numerical simulations for single-waveguide transmission with a system of N coupled nonlinear Schrödinger equations with 2 ≤ N ≤ 4 show excellent agreement with the predator-prey model's predictions and stable propagation over significantly larger distances compared with other broadband nonlinear single-waveguide systems. Moreover, stable on-off and off-on switching of multiple soliton sequences and stable multiple transmission switching events are demonstrated by the simulations. We discuss the reasons for the robustness and scalability of transmission stabilization and switching in waveguides with broadband delayed Raman response and narrowband nonlinear gain-loss, and explain their advantages compared with other broadband nonlinear waveguides.

Stress, coping, and depression: testing new hypotheses in a prospectively studied general population sample of U.S. born Whites and Blacks

PubMed Central

Keyes, K.M.; Barnes, D.; Bates, L.M.

2010-01-01

The scarcity of empirically supported explanations for the Black/White prevalence difference in depression in the U.S. is a conspicuous gap in the literature. Recent evidence suggests that the paradoxical observation of decreased risk of depression but elevated rates of physical illness among Blacks in the U.S. compared with Whites may be accounted for by the use of coping behaviors (e.g., alcohol and nicotine consumption, overeating) among Blacks exposed to high stress levels. Such coping behaviors may mitigate deleterious effects of stressful exposures on mental health while increasing the risk of physical ailments. The racial patterning in mental and physical health outcomes could therefore be explained by this mechanism if a) these behaviors were more prevalent among Blacks than Whites and/or b) the effect of these behavioral responses to stress was differential by race. The present study challenges this hypothesis using longitudinal, nationally-representative data with comprehensive DSM-IV diagnoses. Data are drawn from 34,653 individuals sampled in Waves 1 (2001-2002) and 2 (2004-2005) as part of the US National Epidemiologic Survey on Alcohol and Related Conditions. Results showed that a) Blacks were less likely to engage in alcohol or nicotine consumption at low, moderate, and high levels of stress compared to Whites, and b) there was a significant three-way interaction between race, stress, and coping behavior for BMI only (F=2.11, df=12, p=0.03), but, contrary to the hypothesis, elevated BMI was protective against depression in Blacks at low, not high, levels of stress. Further, engagement in unhealthy behaviors, especially at pathological levels, did not protect against depression in Blacks or in Whites. In sum, the impact of stress and coping processes on depression do not appear to operate differently in Blacks versus Whites. Further research testing innovative hypotheses that would explain the difference in Black/White depression prevalence is warranted. PMID:21227557

Stress, coping, and depression: testing a new hypothesis in a prospectively studied general population sample of U.S.-born Whites and Blacks.

PubMed

Keyes, K M; Barnes, David M; Bates, L M

2011-03-01

The scarcity of empirically supported explanations for the Black/White prevalence difference in depression in the U.S. is a conspicuous gap in the literature. Recent evidence suggests that the paradoxical observation of decreased risk of depression but elevated rates of physical illness among Blacks in the U.S. compared with Whites may be accounted for by the use of coping behaviors (e.g., alcohol and nicotine consumption, overeating) among Blacks exposed to high stress levels. Such coping behaviors may mitigate deleterious effects of stressful exposures on mental health while increasing the risk of physical ailments. The racial patterning in mental and physical health outcomes could therefore be explained by this mechanism if a) these behaviors were more prevalent among Blacks than Whites and/or b) the effect of these behavioral responses to stress was differential by race. The present study challenges this hypothesis using longitudinal, nationally-representative data with comprehensive DSM-IV diagnoses. Data are drawn from 34,653 individuals sampled in Waves 1 (2001-2002) and 2 (2004-2005) as part of the US National Epidemiologic Survey on Alcohol and Related Conditions. Results showed that a) Blacks were less likely to engage in alcohol or nicotine consumption at low, moderate, and high levels of stress compared to Whites, and b) there was a significant three-way interaction between race, stress, and coping behavior for BMI only (F = 2.11, df = 12, p = 0.03), but, contrary to the hypothesis, elevated BMI was protective against depression in Blacks at low, not high, levels of stress. Further, engagement in unhealthy behaviors, especially at pathological levels, did not protect against depression in Blacks or in Whites. In sum, the impact of stress and coping processes on depression does not appear to operate differently in Blacks versus Whites. Further research testing innovative hypotheses that would explain the difference in Black/White depression prevalence is warranted. Copyright © 2010 Elsevier Ltd. All rights reserved.