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91.
Männikkö Niko Ruotsalainen Heidi Tolvanen Asko Kääriäinen Maria 《International journal of mental health and addiction》2020,18(4):993-1007
International Journal of Mental Health and Addiction - The objective of this work was to examine the connections between problematic digital gaming and various health-related behavior... 相似文献
92.
Size matters: effects of stimulus size, duration and eccentricity on the visual gamma-band response.
Niko A Busch Stefan Debener Cornelia Kranczioch Andreas K Engel Christoph S Herrmann 《Clinical neurophysiology》2004,115(8):1810-1820
OBJECTIVE: The effects of stimulus size, duration and eccentricity on the visual gamma-band response (GBR) in human EEG were investigated and compared to visual evoked potentials (VEPs) in order to differentiate in future (and past) experiments whether changes in GBRs are due to stimulus-related (exogenous) or cognitive effects. METHODS: EEG was recorded from 23 subjects while they performed a simple choice reaction time task requiring discrimination of squares and circles. In separate blocks stimulus size, duration, and eccentricity were manipulated. EEG was recorded from 64 electrodes. A wavelet transform based on Morlet wavelets was employed for the analysis of gamma-band activity. RESULTS: Amplitude of the GBR was diminished for small and peripheral stimuli. With short stimulus durations ON and OFF responses of the GBR merged into one peak. In comparison, VEP amplitudes were less susceptible to stimulus features. In contrast to VEP latencies, however, GBR latency did not show a lateralization for eccentric stimuli. CONCLUSIONS: In addition to previous experiments which have shown a modulation of the GBR by various cognitive processes, the present results demonstrate the susceptibility of the GBR in human EEG to exogenous factors, as numerous intracortical recordings in non-human primates have shown before. The results suggest that the human GBR resides in early visual areas. SIGNIFICANCE: The demonstration of the susceptibility of the GBR to stimulus properties implies that studies aimed at exploring the involvement of the GBR in information processing have to be designed carefully. It also constrains the localization of the human GBR. 相似文献
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Niko Männikkö Heidi Ruotsalainen Zsolt Demetrovics Olatz Lopez-Fernandez Laura Myllymäki Jouko Miettunen 《Behavioral medicine (Washington, D.C.)》2018,44(4):324-334
Multiplatform digital media use and gaming have been increased in recent years. The aim of this study was to examine associations between sociodemographics and digital gaming behavior characteristics (i.e., gaming time, medium, and genres) with problematic gaming behavior in adolescents. A convenience sample of Finnish junior high school students (n = 560; mean age 14 years, ranging from 12 to 16 years) participated in the cross-sectional survey, of which, 83% (n = 465) reported having played digital games regularly. Sociodemographic data, different forms of digital media use, gaming behavior characteristics and problematic gaming behavior was assessed. Study participants spent on average one hour per day playing digital games; casual games (23.9%), shooting games (19.8%), and sport games (12.9%), were the most popular games among participants. By using regression analysis, a blended family structure and gaming time related positively to problematic gaming behavior. Preferences for game genres such as solo, Massively Multiplayer Online Role-Playing and strategy-management games were also positively associated with problematic use of digital games. These findings provide knowledge that can be utilized in the prevention of the possible negative consequences of digital gaming. 相似文献
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There is need to enable different superimposed part structure solutions as part of the design process and identify these solution
options to support configuration of life-cycle phases and change management. This requirement is one of the important needs
of integrated structure configurations in modular product architectures in commercial marine product platforms. The solution
of the study is part of a model definition that enables superimposed solution structure definition in away that part and document
definition is managed through change process effectively in product data management systems. 相似文献
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Pattern‐mixture models (PMM) and selection models (SM) are alternative approaches for statistical analysis when faced with incomplete data and a nonignorable missing‐data mechanism. Both models make empirically unverifiable assumptions and need additional constraints to identify the parameters. Here, we first introduce intuitive parameterizations to identify PMM for different types of outcome with distribution in the exponential family; then we translate these to their equivalent SM approach. This provides a unified framework for performing sensitivity analysis under either setting. These new parameterizations are transparent, easy‐to‐use, and provide dual interpretation from both the PMM and SM perspectives. A Bayesian approach is used to perform sensitivity analysis, deriving inferences using informative prior distributions on the sensitivity parameters. These models can be fitted using software that implements Gibbs sampling. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Esa Pitk?nen Tatiana Cajuso Riku Katainen Eevi Kaasinen Niko V?lim?ki Kimmo Palin Jussi Taipale Lauri A. Aaltonen Outi Kilpivaara 《Oncotarget》2014,5(3):853-859
L1 element retrotranspositions have been found to alter expression of genes neighboring the insertion sites, potentially involving them in tumorigenesis and tumor progression. In colorectal cancer (CRC), L1 insertions have been found to target genes with a role in tumorigenesis. Structural changes such as L1 insertions are identifiable by whole genome sequencing (WGS). In this study, we observed frequent somatic L1 retrotranspositions originating from TTC28 using deep coverage WGS data from 92 CRC tumor-normal sample pairs. In two cases the event had targeted NOVA1 gene (p=0.025). In addition, a germline retrotransposition event from TTC28 to GABRA4 was found to be a common polymorphism in the Finnish population. Thus while some events may be tumorigenic, others are likely to be neutral. Our data contradict a recent study where a similar signal in TTC28 was interpreted as a common inactivating translocation. While much work remains to be performed to understand the biological significance of retrotranspositions in cancer, accurate identification of these events is a prerequisite for success. 相似文献