48 research outputs found

    Review of Inverse Laplace Transform Algorithms for Laplace-Space Numerical Approaches

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    A boundary element method (BEM) simulation is used to compare the efficiency of numerical inverse Laplace transform strategies, considering general requirements of Laplace-space numerical approaches. The two-dimensional BEM solution is used to solve the Laplace-transformed diffusion equation, producing a time-domain solution after a numerical Laplace transform inversion. Motivated by the needs of numerical methods posed in Laplace-transformed space, we compare five inverse Laplace transform algorithms and discuss implementation techniques to minimize the number of Laplace-space function evaluations. We investigate the ability to calculate a sequence of time domain values using the fewest Laplace-space model evaluations. We find Fourier-series based inversion algorithms work for common time behaviors, are the most robust with respect to free parameters, and allow for straightforward image function evaluation re-use across at least a log cycle of time

    Gender Differences in Attitudes towards Prevention and Intervention Messages for Digital Addiction

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    It has been suggested that excessive use of the internet and digital devices can lead to digital addiction (DA). In contrast to other industries such as the alcohol industry there appears to be very little expectation on the software industry to position itself as a primary actor in the development of DA; even though software providers have unique capabilities to engage with users in real time and in a personalised way through multi-modal interactive and intelligent prevention and intervention messages. One aspect of personalisation that has been demonstrated to be of importance in relation to DA and other compulsive behaviours is gender. This study consisted of a series of initial exploratory interviews followed by a survey of 150 respondents and several same-sex focus groups, the latter of which was recruited from a university student sample. Thematic and quantitative analyses were then conducted on the data gathered. Overall participants welcomed the idea of DA prevention and intervention messages, although they also demonstrated a clear preference for any DA prevention and intervention messages system to be adaptive and context aware. Some gender differences were evident, such as in terms for acceptance of messages generated by friends or the preference for graphical messages. The results of this study suggest that DA prevention and intervention messages may be useful to and welcomed by individuals who use digital technologies excessively. However, these users also appear to have expectations of what a successful DA prevention and intervention messages system should be able to achieve. Further research is needed on this emergent topic

    Factors Relating to Managerial Stereotypes: The Role of Gender of the Employee and the Manager and Management Gender Ratio

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    Several studies have shown that the traditional stereotype of a "good" manager being masculine and male still exists. The recent changes in the proportion of women and female managers in organizations could affect these two managerial stereotypes, leading to a stronger preference for feminine characteristics and female leaders. This study examines if the gender of an employee, the gender of the manager, and the management gender ratio in an organization are related to employees' managerial stereotypes. 3229 respondents working in various organizations completed an electronic questionnaire. The results confirm our hypotheses that, although the general stereotype of a manager is masculine and although most prefer a man as a manager, female employees, employees with a female manager, and employees working in an organization with a high percentage of female managers, have a stronger preference for feminine characteristics of managers and for female managers. Moreover, we find that proximal variables are much stronger predictors of these preferences than more distal variables. Our study suggests that managerial stereotypes could change as a result of personal experiences and changes in the organizational context. The results imply that increasing the proportion of female managers is an effective way to overcome managerial stereotyping. This study examines the influence on managerial stereotypes of various proximal and distal factors derived from theory among a large group of employees (in contrast to students)

    The Netherlands study of depression in older persons (NESDO); a prospective cohort study

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    <p>Abstract</p> <p>Background</p> <p>To study late-life depression and its unfavourable course and co morbidities in The Netherlands.</p> <p>Methods</p> <p>We designed the Netherlands Study of Depression in Older Persons (NESDO), a multi-site naturalistic prospective cohort study which makes it possible to examine the determinants, the course and the consequences of depressive disorders in older persons over a period of six years, and to compare these with those of depression earlier in adulthood.</p> <p>Results</p> <p>From 2007 until 2010, the NESDO consortium has recruited 510 depressed and non depressed older persons (≥ 60 years) at 5 locations throughout the Netherlands. Depressed persons were recruited from both mental health care institutes and general practices in order to include persons with late-life depression in various developmental and severity stages. Non-depressed persons were recruited from general practices. The baseline assessment included written questionnaires, interviews, a medical examination, cognitive tests and collection of blood and saliva samples. Information was gathered about mental health outcomes and demographic, psychosocial, biological, cognitive and genetic determinants. The baseline NESDO sample consists of 378 depressed (according to DSM-IV criteria) and 132 non-depressed persons aged 60 through 93 years. 95% had a major depression and 26.5% had dysthymia. Mean age of onset of the depressive disorder was around 49 year. For 33.1% of the depressed persons it was their first episode. 41.0% of the depressed persons had a co morbid anxiety disorder. Follow up assessments are currently going on with 6 monthly written questionnaires and face-to-face interviews after 2 and 6 years.</p> <p>Conclusions</p> <p>The NESDO sample offers the opportunity to study the neurobiological, psychosocial and physical determinants of depression and its long-term course in older persons. Since largely similar measures were used as in the Netherlands Study of Depression and Anxiety (NESDA; age range 18-65 years), data can be pooled thus creating a large longitudinal database of clinically depressed persons with adequate power and a large set of neurobiological, psychosocial and physical variables from both younger and older depressed persons.</p

    Plasma biomarkers of depressive symptoms in older adults

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    The pathophysiology of negative affect states in older adults is complex, and a host of central nervous system and peripheral systemic mechanisms may play primary or contributing roles. We conducted an unbiased analysis of 146 plasma analytes in a multiplex biochemical biomarker study in relation to number of depressive symptoms endorsed by 566 participants in the Alzheimer's Disease Neuroimaging Initiative (ADNI) at their baseline and 1-year assessments. Analytes that were most highly associated with depressive symptoms included hepatocyte growth factor, insulin polypeptides, pregnancy-associated plasma protein-A and vascular endothelial growth factor. Separate regression models assessed contributions of past history of psychiatric illness, antidepressant or other psychotropic medicine, apolipoprotein E genotype, body mass index, serum glucose and cerebrospinal fluid (CSF) τ and amyloid levels, and none of these values significantly attenuated the main effects of the candidate analyte levels for depressive symptoms score. Ensemble machine learning with Random Forests found good accuracy (∼80%) in classifying groups with and without depressive symptoms. These data begin to identify biochemical biomarkers of depressive symptoms in older adults that may be useful in investigations of pathophysiological mechanisms of depression in aging and neurodegenerative dementias and as targets of novel treatment approaches

    The emerging modern face of mood disorders: a didactic editorial with a detailed presentation of data and definitions

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    The present work represents a detailed description of our current understanding and knowledge of the epidemiology, etiopathogenesis and clinical manifestations of mood disorders, their comorbidity and overlap, and the effect of variables such as gender and age. This review article is largely based on the 'Mood disorders' chapter of the Wikibooks Textbook of Psychiatry http://en.wikibooks.org/wiki/Textbook_of_Psychiatry/Mood_Disorders

    Company-level family policies: Who has access to it and what are some of its outcomes

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    Despite the increase in number of studies that examine the cross-national variation in the policy configuration that allow a better work-family integration, very few look beyond the national levels. It is also crucial to examine occupational level welfare since companies may restrict or expand the existing national level regulations, defining the “final availability” workers actual have towards various arrangements. In addition, companies may provide various additional arrangements through occupational policies which are not set out in the national level agreements that are crucial in addressing reconciliation needs of workers. This chapter examines what types of arrangements are provided at the company level to address work-family demands of workers. It further provides a synthesis of studies that examine both national level contexts and individual level characteristics that explain who gets access to company level family-friendly policies, which is linked to the possible outcomes of these policies

    Leveraging the macro-level environment to balance work and life: an analysis of female entrepreneurs' job satisfaction

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    This study investigates the interactive effect of female entrepreneurs’ experience of work–life imbalance and gender-egalitarian macro-level conditions on their job satisfaction, with the prediction that the negative linear relationship between work–life imbalance and job satisfaction may be buffered by the presence of women-friendly action resources, emancipative values, and civic entitlements. Data pertaining to 7,392 female entrepreneurs from 44 countries offer empirical support for these predictions. Female entrepreneurs who are preoccupied with their ability to fulfill both work and life responsibilities are more likely to maintain a certain level of job satisfaction, even if they experience significant work–life imbalances, to the extent that they operate in supportive macro-level environments
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