Loneliness among single and coupled individuals in response to the COVID-19 pandemic: A cross-country analysis

Background/Objective

Research suggests that the COVID-19 pandemic has increased social isolation and loneliness and that, in general, single individuals experience a higher degree of loneliness than coupled individuals. Loneliness may also vary across cultures as a function of social norms and Hofstede's dimensions of national culture. Therefore, the aim of the present study was to examine whether the link between relationship status and loneliness in the context of the COVID-19 pandemic differed across countries as a function of cultural values captured in terms of Hofstede's six dimensions of national culture.

Method

Multilevel modeling was used to analyze the archival data collected in the COVIDiSTRESS Global Survey (41 countries and 102,957 participants) and the COVIDiSTRESS Global Survey - Round II (23 countries and 8227 participants).

Results

The analyses demonstrated the statistical significance of the interactions between relationship status and six Hofstede's dimensions of national culture in the link between relationship status and loneliness. The estimated effect sizes of these interactions were, however, almost zero.

Conclusions

The lack of effect size of the interactions between relationship status and Hofstede's dimensions of national culture for loneliness may have substantive significance. This finding implies that, on average, loneliness as a function of relationship status may be less reactive in the context of the COVID-19 pandemic to the effects of social norms and values across which countries vary.

Group analysis of ongoing EEG data based on fast double-coupled nonnegative tensor decomposition

BACKGROUND

Ongoing EEG data are recorded as mixtures of stimulus-elicited EEG, spontaneous EEG and noises, which require advanced signal processing techniques for separation and analysis. Existing methods cannot simultaneously consider common and individual characteristics among/within subjects when extracting stimulus-elicited brain activities from ongoing EEG elicited by 512-s long modern tango music.

NEW METHOD

Aiming to discover the commonly music-elicited brain activities among subjects, we provide a comprehensive framework based on fast double-coupled nonnegative tensor decomposition (FDC-NTD) algorithm. The proposed algorithm with a generalized model is capable of simultaneously decomposing EEG tensors into common and individual components.

RESULTS

With the proposed framework, the brain activities can be effectively extracted and sorted into the clusters of interest. The proposed algorithm based on the generalized model achieved higher fittings and stronger robustness. In addition to the distribution of centro-parietal and occipito-parietal regions with theta and alpha oscillations, the music-elicited brain activities were also located in the frontal region and distributed in the 4∼11 Hz band.

COMPARISON WITH EXISTING METHOD(S)

The present study, by providing a solution of how to separate common stimulus-elicited brain activities using coupled tensor decomposition, has shed new light on the processing and analysis of ongoing EEG data in multi-subject level. It can also reveal more links between brain responses and the continuous musical stimulus.

CONCLUSIONS

The proposed framework based on coupled tensor decomposition can be successfully applied to group analysis of ongoing EEG data, as it can be reliably inferred that those brain activities we obtained are associated with musical stimulus.

Fixed-time synchronization of coupled memristor-based neural networks with time-varying delays

This paper investigates the fixed-time synchronization of Memristor-based neural networks with time-delayed and coupled. In view of the retarded differential inclusions theory, drive-response concept, the authors give some sufficient conditions to ensure the fixed-time synchronization issue of Memristor-based neural networks. Two novel state-feedback controllers and adaptive controller are designed such that the system can realize fixed-time complete synchronization by means of inequality technique and non-smooth analysis theory. It is worth to point out that, without desiring values of the initial conditions or under the linear growth condition of the controller, the settling time of fixed-time synchronization is estimated. Finally, an example is given to further illustrate the benefits of the proposed switched control approach.

Modeling fully coupled hydraulic-mechanical-chemical processes in a natural clay liner under mechanical and chemico-osmotic consolidation

Clayey material that possesses semipermeable membrane property may experience osmotic consolidation in presence of an osmotic gradient. In this paper, a fully coupled H-M-C model has been presented to study solute transport under the combined influence of mechanical and osmotic consolidations and vice versa. The model has been tested against the results of relevant importance and good agreements have been achieved. The model has been applied to investigate long-term solute transport behavior and consequent deformations/settlements in a natural clay liner. The results suggest, at early stages, solute transport is dominated by mechanical consolidation; however, physicochemical interaction associated with osmotic processes and osmotic consolidation dominates in the long term. Osmotic settlement shows decreasing trend past the maximum deformation of the clay liner indicating reduction of osmotic gradient across the semipermeable membrane. It is also evident that overall soil consolidation and transport of solute are affected by the concentration of the solute at the source or the injection boundary.

Coupled, multi-strain epidemic models of mutating pathogens

We introduce and analyze coupled, multi-strain epidemic models designed to simulate the emergence and dissemination of mutant (e.g. drug-resistant) pathogen strains. In particular, we investigate the mathematical and biological properties of a general class of multi-strain epidemic models in which the infectious compartments of each strain are coupled together in a general manner. We derive explicit expressions for the basic reproduction number of each strain and highlight their importance in regulating the system dynamics (e.g. the potential for an epidemic outbreak) and the existence of nonnegative endemic solutions. Importantly, we find that the basic reproduction number of each strain is independent of the mutation rates between the strains - even under quite general assumptions for the form of the infectious compartment coupling. Moreover, we verify that the coupling term promotes strain coexistence (as an extension of the competitive exclusion principle) and demonstrate that the strain with the greatest reproductive capacity is not necessarily the most prevalent. Finally, we briefly discuss the implications of our results for public health policy and planning.