Problematic online behaviors among adolescents and emerging adults: associations between cyberbullying perpetration, problematic social media use, and psychosocial factors

Over the past two decades, young people's engagement in online activities has grown markedly. The aim of the present study was to examine the relationship between two specific online behaviors (i.e., cyberbullying perpetration, problematic social media use) and their relationships with social connectedness, belongingness, depression, and self-esteem among high school and university students. Data were collected from two different study groups via two questionnaires that included the Cyberbullying Offending Scale, Social Media Use Questionnaire, Social Connectedness Scale, General Belongingness Scale, Short Depression-Happiness Scale, and Single Item Self-Esteem Scale. Study 1 comprised 804 high school students (48% female; mean age 16.20 years). Study 2 comprised 760 university students (60% female; mean age 21.48 years). Results indicated that problematic social media use and cyberbullying perpetration (which was stronger among high school students) were directly associated with each other. Belongingness (directly) and social connectedness (indirectly) were both associated with cyberbullying perpetration and problematic social media use. Path analysis demonstrated that while age was a significant direct predictor of problematic social media use and cyberbullying perpetration among university students, it was not significant among high school students. In both samples, depression was a direct predictor of problematic social media use and an indirect predictor of cyberbullying perpetration. However, majority of these associations were relatively weak. The present study significantly adds to the emerging body of literature concerning the associations between problematic social media use and cyberbullying perpetration

The association between functional status and physical pain with depressive symptoms after a stroke event: A cross-sectional analysis of the China Health and Retirement Longitudinal Study 2018

Background: Stroke is a major cause of mortality and long-term physical and cognitive impairment. This study aims to: (1) examine the prevalence of depressive symptoms, disability and pain among Chinese adults with stroke; (2) test the associations of functional limitations and body pain with occurrence of depressive symptoms; (3) investigate gender and urban-rural disparities in these associations. Methods: This study utilized the data from the China Health and Retirement Longitudinal Study in 2018, involving 969 patients with stroke among 17,970 participants aged ≥ 45 years. Depressive symptoms were assessed using the 10-item Center for Epidemiologic Studies Depression (CES-D) Scale. We performed multivariable logistic regression models to estimate the associations between activities of daily life (ADL), instrumental activities of daily life (IADL) and pain with depressive symptoms. Results: Depressive symptoms were found among 40.2% of stroke patients, with a higher prevalence in females (48.2%) than males (32.7%). Prevalence of ADL limitations, IADL limitations and pain among stroke patients were 39.2, 49.8 and 14.0%, respectively. ADL and IADL limitations and pain were more prevalent among females and residents in rural areas. Multivariable regression analyses showed a significant association between ADL limitation (OR = 1.535, 95% CI = 1.168, 2.018), IADL limitation (OR = 1.666, 95% CI = 1.260, 2.203) and pain (OR = 2.122, 95% CI = 1.466, 3.073) with depressive symptoms. Stratified analyses revealed stronger associations among urban residents. Females had a higher association of ADL and IADL with depressive symptoms but similar in that of pain to the males. The impact of ADL and IADL in male patients is higher than in females, but the impact of pain on depressive symptoms is higher in female patients. Conclusion: Depressive symptoms are common amongst post-stroke patients in China and are significantly associated with functional disability and physical pain. Our findings have implications for practitioners on the early assessment of pain and depression after stroke. Future research should explore effective intervention measures for physical-mental stroke complications

When workplace unionism in global value chains does not function well : exploring the impediments

Improving working conditions at the bottom of global value chains has become a central issue in our global economy. In this battle, trade unionism has been presented as a way for workers to make their voices heard. Therefore, it is strongly promoted by most social standards. However, establishing a well-functioning trade union is not as obvious as it may seem. Using a comparative case study approach, we examine impediments to farm-level unionism in the cut flower industry in Ethiopia. For this purpose, we propose an integrated framework combining two lenses, namely a vertical one (governance and structure of global value chains) and a horizontal one (socio-economic context). We identify 10 impediments that point to three major dimensions contributing to unionisation. These three dimensions include awareness of and interest from workers, legitimacy of trade unions, and capacity of trade unions to act. Furthermore, our results suggest that private social standards may, in certain cases, be counterproductive for the efficient functioning of trade unions. Although we argue that there is no ‘quick fix’ solution to weak workplace unionism at the bottom of global value chains, we stress the importance of considering the dynamics of, and interactions between, the impediments when designing potential support measures that mitigate negative impacts

Fructan and its relationship to abiotic stress tolerance in plants

Numerous studies have been published that attempted to correlate fructan concentrations with freezing and drought tolerance. Studies investigating the effect of fructan on liposomes indicated that a direct interaction between membranes and fructan was possible. This new area of research began to move fructan and its association with stress beyond mere correlation by confirming that fructan has the capacity to stabilize membranes during drying by inserting at least part of the polysaccharide into the lipid headgroup region of the membrane. This helps prevent leakage when water is removed from the system either during freezing or drought. When plants were transformed with the ability to synthesize fructan, a concomitant increase in drought and/or freezing tolerance was confirmed. These experiments indicate that besides an indirect effect of supplying tissues with hexose sugars, fructan has a direct protective effect that can be demonstrated by both model systems and genetic transformation

Computing Highly Correlated Positions Using Mutual Information and Graph Theory for G Protein-Coupled Receptors

G protein-coupled receptors (GPCRs) are a superfamily of seven transmembrane-spanning proteins involved in a wide array of physiological functions and are the most common targets of pharmaceuticals. This study aims to identify a cohort or clique of positions that share high mutual information. Using a multiple sequence alignment of the transmembrane (TM) domains, we calculated the mutual information between all inter-TM pairs of aligned positions and ranked the pairs by mutual information. A mutual information graph was constructed with vertices that corresponded to TM positions and edges between vertices were drawn if the mutual information exceeded a threshold of statistical significance. Positions with high degree (i.e. had significant mutual information with a large number of other positions) were found to line a well defined inter-TM ligand binding cavity for class A as well as class C GPCRs. Although the natural ligands of class C receptors bind to their extracellular N-terminal domains, the possibility of modulating their activity through ligands that bind to their helical bundle has been reported. Such positions were not found for class B GPCRs, in agreement with the observation that there are not known ligands that bind within their TM helical bundle. All identified key positions formed a clique within the MI graph of interest. For a subset of class A receptors we also considered the alignment of a portion of the second extracellular loop, and found that the two positions adjacent to the conserved Cys that bridges the loop with the TM3 qualified as key positions. Our algorithm may be useful for localizing topologically conserved regions in other protein families

Polar Code for Future 60 GHz Millimeter-Wave Communications

With high operating frequencies and high emission power, 60 GHz millimeter communications may suffer seriously from realistic hardware impairments. Among this, nonlinear power amplifier (PA) will significantly degrade its transmission performance. In order to decrease the bits error rate (BER) of 60 GHz millimeter communications, in this investigation a promising polar coding scheme is proposed. Based on the derivation of the general formulas of polar code, a new construction scheme for polar code is proposed. This designed polar code is further applied to 60 GHz systems with nonlinear PA. Experimental simulations verified the proposed coding scheme, which may significantly promote the transmission performance of 60 GHz communications. It is also demonstrated that the proposed polar coding scheme will surpass the popular LDPC code, which hence provides a great promise to practical use