The use of the Internet as a research tool: the nature and characteristics of seasonal affective disorder (SAD) amongst a population of users

Seasonal affective disorder (SAD) is a cyclical syndrome characterized by recurrent episodes of autumn or winter depression and atypical depressive symptoms. This paper describes the characteristics of an international sample of 425 Internet users who responded to newsgroup advertisements seeking people who experienced seasonal changes in mood and behaviour, and completed a modified version of the Seasonal Patterns Assessment Questionnaire. The relationship between SAD and latitude and the relatively novel use of the Internet as a means of data collection are discussed, with emphasis upon the theoretical, methodological and ethical issues encountered during such research.     

The use of the Internet as a research tool: the nature and characteristics of seasonal affective disorder (SAD) amongst a population of users

Seasonal affective disorder (SAD) is a cyclical syndrome characterized by recurrent episodes of autumn or winter depression and atypical depressive symptoms. This paper describes the characteristics of an international sample of 425 Internet users who responded to newsgroup advertisements seeking people who experienced seasonal changes in mood and behaviour, and completed a modified version of the Seasonal Patterns Assessment Questionnaire. The relationship between SAD and latitude and the relatively novel use of the Internet as a means of data collection are discussed, with emphasis upon the theoretical, methodological and ethical issues encountered during such research.     

Prevalence of perceived stress,symptoms of depression and sleep disturbances in relation to information and communication technology (ICT) use among young adults – an explorative prospective study

The aim of this study was to prospectively investigate whether high quantity of information and communication technology (ICT) use is a risk factor for developing psychological symptoms among young ICT users. A cohort of college students responded to a questionnaire at baseline and at 1-year follow-up (n = 1127). Exposure variables, such as different types of ICT use, and effect variables, such as perceived stress, symptoms of depression and sleep disturbances, were assessed. Prevalence ratios were computed, based on symptom-free subjects at baseline and prevalence of symptoms at follow-up. For women, high combined use of computer and mobile phone at baseline was associated with increased risk of reporting prolonged stress and symptoms of depression at follow-up, and number of short message service (SMS) messages per day was associated with prolonged stress. Also online chatting was associated with prolonged stress, and e-mailing and online chatting were associated with symptoms of depression, while Internet surfing increased the risk of developing sleep disturbances. For men, number of mobile phone calls and SMS messages per day were associated with sleep disturbances. SMS use was also associated with symptoms of depression. The findings suggest that ICT may have an impact on psychological health, although causal mechanisms are unclear.     

Workload and musculoskeletal problems: a comparison between welders and office clerks (with reference also to fishermen)

Previous studies have shown that subjective as well as clinical shoulder signs and symptoms are more common among welders than among office clerks. In the present study we wished to further evaluate the influence of different jobs on musculoskeletal problems, as well as the relationship between objective signs and subjective symptoms. This study confirmed that symptoms and signs from the shoulder were more common among the welders, who also had more subjective symptoms and clinical signs from other parts of the musculoskeletal system, Range of motion in different joint systems was, however, similar in the two groups except in external rotation of the shoulder, where welders had a more limited range. The degree of co-existence of subjective symptoms and clinical signs differed between different parts of the musculoskeletal system and was low particularly in the low back, hips, and ankles. This indicates low validity of many common clinical methods for determining musculoskeletal dysfunciion. General health was good in both vocational groups and isometric strength for the welders was intermediate between that of office clerks (who had lower strength) and that of fishermen (who had higher strength, as disclosed in a previous investigation). To a similar degree welders and fishermen also had objective signs from most parts of the musculoskeletal system, whereas subjective symptoms from some parts of the body and medical consultations due to these problems were more common among welders. Atrophied shoulder muscles were more common among welders than among fishermen, whereas crepitations in the shoulder tended to be more common among the fishermen. This indicates that heavy dynamic work and prolonged static work may both induce shoulder injuries, but of different types.     

Civic Technology and Community Building: Interaction Effects Between Integrated Connectedness to a Storytelling Network (ICSN) and Internet and Mobile Uses on Civic Participation

This study draws on communication infrastructure theory (CIT) to examine the extent to which expressive uses of Internet and mobile devices moderate the relationship between integrated connectedness to a storytelling network (ICSN) and offline and online civic participation. Data collected through a Web survey of a U.S. national online panel (N = 1201) reveal that the relationships of ICSN with offline and online civic participation are conditioned by locality‐oriented expressive uses of Internet and mobile media. With these findings, this study discusses theoretical insights, policy implications, and practical applications.     

Revised photochemical reflectance index (PRI) for predicting light use efficiency of wheat in a growth cycle: validation and comparison

The photochemical reflectance index (PRI) was developed to trace the changes in light use efficiency (LUE) as the two contributing reflectances at 531 nm and 570 nm are closely related to the xanthophyll pigment cycle. In this paper, two revised indices of PRI (PRI_R1 and PRI_R2) are derived for a better prediction of LUE during the growth cycle of wheat. The signal of chlorophyll content (reflectance at 550 nm) to PRI is incorporated so that the revised indices can be used to estimate LUE values at low chlorophyll concentration. A validation was conducted using ground data (reflectance and LUE data) during a growth cycle of wheat in 2007 (17 April, 28 April, 16, 29 May). The results demonstrate that PRI cannot be used as an index for LUE estimation during the growth cycle of wheat as the relationship between PRI and LUE significantly weakened (R² = 0.20) on 29 May when the leaves lost chlorophyll concentration in the senescent period. PRI_R1 and PRI_R2 are more robust than PRI for LUE estimationm, not only with a relatively stable precision (R² = 0.62, 0.76, 0.62, 0.57 for PRI_R1 and R² = 0.62, 0.76, 0.63, 0.59 for PRI_R2) but also with better linearity with LUE (standard error of regression equation between LUE and index is 0.00187, 0.00127, 0.00116, 0.00103 for PRI_R1 and 0.00186, 0.00117, 0.00114, 0.00102 for PRI_R2). The result of the comparison analysis indicates that the revised indices (PRI_R1 and PRI_R2) are more sensitive than PRI to low chlorophyll content and low leaf area index, which means they are more appropriate for LUE interpretation in these situations. Sensitivity of Sun-sensor geometry to all indices implies that all indices exhibit large variations with changes in solar zenith angle and view zenith angle. As solar zenith angle increases, all indices display different sensitivity patterns before and after hotspot positions. All indices vary greatly as the view zenith angle increases. An acceptable precision of all indices can be acquired within a departure of 10° from the nadir view.     

Study of the Radio Frequency (RF) performance of a Wafer-Level Package (WLP) with Through Silicon Vias (TSVs) for the integration of RF-MEMS and micromachined waveguides in the context of 5G and Internet of Things (IoT) applications. Part 2: parameterised 3D model and optimisation

Microsystem Technologies - This study discusses the exploitation of a full-3D methodology for the electromagnetic simulation of a Wafer-Level Packaging solution featuring Through Silicon Vias...     

ISOPAQ,a MATLAB program for stratigraphic and isopach mapping: example application to the French Bajocian (Jurassic) sediments

The three-dimensional reconstruction of basin sediments has become a major topic in earth sciences and is now a necessary step for modeling and understanding the depositional context of sediments. Because data are generally scattered, the construction of any irregular, continuous surface involves the interpolation of a large number of points over a regular grid. However, interpolation is a highly technical specialty that is still somewhat of a black art for most people. The lack of multi-platform contouring software that is easy to use, fast and automatic, without numerous abstruse parameters, motivated the programming of a software, called ISOPAQ. This program is an interactive desktop tool for spatial analysis, interpolation and display (location, contour and surface mapping) of earth science data, especially stratigraphic data. It handles four-dimensional data sets, where the dimensions are usually longitude, latitude, thickness and time, stored in a single text file. The program uses functions written for the MATLAB^® software. Data are managed by the means of a user-friendly graphical interface, which allows the user to interpolate and generate maps for stratigraphic analyses. This program can process and compare several interpolation methods (nearest neighbor, linear and cubic triangulations, inverse distance and surface splines) and some stratigraphic treatments, such as the decompaction of sediments. Moreover, the window interface helps the user to easily change some parameters like coordinates, grid cell size, and equidistance of contour lines and scale between files. Primarily developed for non-specialists of interpolation thanks to the graphical user interface, practitioners can also easily append the program with their own functions, since it is written in MATLAB open language. As an example, the program is applied here to the Bajocian stratigraphic sequences of eastern France.     

Evaluation of standard and regional satellite chlorophyll-a algorithms for moderate-resolution imaging spectroradiometer (MODIS) in the Bohai and Yellow Seas,China: a comparison of chlorophyll-a magnitude and seasonality

Retrieval of satellite remotely sensed chlorophyll-a (chl-a) concentrations in coastal regions such as the Bohai and Yellow Seas (BYS) is challenging due to their complex oceanic and atmospheric optical properties. The standard OC3M (ocean chl-a three-band algorithm for MODIS (moderate-resolution imaging spectroradiometer)) algorithm has been widely used in the BYS, despite well-known uncertainties about its accuracy in terms of absolute magnitude. This was based on the belief that OC3M chl-a is capable of representing reliable relative spatial and temporal patterns of sea surface chl-a concentrations. In this study, the ability of the standard OC3M chl-a algorithm to reproduce accurate seasonality patterns was evaluated, based on comparisons with in situ chl-a measurements in the BYS. The results quantified the overestimation by the standard OC3M algorithm with a median absolute percentage difference of 98.48% and a median relative difference of 1.13 mg m^?3.More importantly, the seasonality from OC3M chl-a was significantly biased relative to the seasonal patterns of in situ chl-a. In addition, a regional GAM (generalized additive model)-based satellite chl-a algorithm was evaluated and compared with OC3M chl-a. The results showed the GAM chl-a improved accuracy in both magnitude and seasonality when compared with in situ chl-a, relative to that from OC3M chl-a.     

The automation design advisor tool (ADAT): Development and validation of a model‐based tool to support flight deck automation design for nextgen operations

NextGen aviation will require an even greater reliance on automation than current‐day operations. Therefore, systems with problems in human–automation interaction must be identified and resolved early, well before they are introduced into operation. This paper describes a research and software development effort to build a prototype automation design advisor tool (ADAT) for flight deck automation. This tool uses models of human performance to identify perceptual, cognitive, and action‐related inefficiencies in the design of flight management systems. Aviation designers can use the tool to evaluate and compare potential flight deck automation designs and to identify potential human–automation interaction concerns. Designers can compare different flight management systems in terms of specific features and their ability to support pilot performance. ADAT provides specific, research‐based guidance for resolving problematic design issues. It was specifically designed to be flexible enough for both current‐day technologies and revolutionary NextGen designs. © 2012 Wiley Periodicals, Inc.     

RECPAM: a computer program for recursive partition amalgamation for censored survival data and other situations frequently occurring in biostatistics. II. Applications to data on small cell carcinoma of the lung (SCCL)

The RECPAM methodology previously presented in part I (A. Ciampi et al., Comput. Methods Programs Biomed. 26 (1988) 239–256) is applied to the analysis of survival data on small cell carcinoma of the lung (SCCL). It is shown how RECPAM can help answer the following questions which occur frequently in the analysis of clinical data: Is it possible to find a classification of patients with a certain disease into distinct prognostic groups? Given a covariate of special interest, does it have an independent prognostic significance even after confounding is taken into account? Does the prognostic significance of a covariate of special interest vary across patient subgroups? For the SCCL data, a prognostic classification is obtained and the tumor marker is treated as a variable of special interest. Many features of RECPAM are illustrated, including, among others, Forward and Backward (Pruning) Stopping Rules, treatment of missing data, and use of several dissimilarity measures.