Effects of a online brief modified mindfulness-based stress reduction therapy for anxiety among Chinese adults: A randomized clinical trial.

The COVID-19 pandemic has exacerbated anxiety and related symptoms among the general population. In order to cope with the mental health burden, we developed an online brief modified mindfulness-based stress reduction (mMBSR) therapy. We performed a parallel-group randomized controlled trial to evaluate the efficacy of the mMBSR for adult anxiety with cognitive-behavioral therapy (CBT) as an active control. Participants were randomized to mMBSR, CBT or waitlist group. Those in the intervention arms performed each therapy for 6 sections in 3 weeks. Measurements were conducted at baseline, post-treatment and 6 months post-treatment by Generalized Anxiety Disorder-7, Patient Health Questionnaire-9, Patient Health Questionnaire-15, reverse scored Cohen Perceived Stress scale, Insomnia Severity Index, and Snaith-Hamilton Pleasure Scale. 150 participants with anxiety symptoms were randomized to mMBSR, CBT or waitlist group. Post intervention assessments showed that mMBSR improved the scores of all the six mental problem dimensions (anxiety, depression, somatization, stress, insomnia, and the experience of pleasure) significantly compared to the waitlist group. During 6-month post treatment assessment, the scores of all six mental problem dimensions in the mMBSR group still showed improvement compared to baseline and showed no significant difference with the CBT group. Our results provide positive evidence for the efficacy and feasibility of an online brief modified MBSR program to alleviate anxiety and related symptoms of individuals from the general population, and the therapeutic benefits of mMBSR persisted for up to six months. This low resource-consuming intervention could facilitate the challenges of supplying psychological health therapy to large scale of population.

Simultaneous toughening and strengthening of chitin-based composites via tensile-induced orientation and hydrogen bond reconstruction.

Chitin, an abundant, biodegradable, and biocompatible polysaccharide, is one of the most ideal eco-friendly alternatives to petroleum-based plastics. However, the applications of chitin-based materials are hindered by their low processability and brittleness induced by strong hydrogen bonds. Herein, a tensile-induced orientation and hydrogen bond reconstruction strategy was developed to fabricate a chitin nanowhiskers/poly(vinyl alcohol) composite film with high strength and toughness. After stretching and hydrogen bond reconstruction, the tensile strength and elongation at break of the composite film increased from 38.6 to 115.2 MPa and 9.37% to 40.7%, respectively. Furthermore, strengthening and toughening mechanisms were also studied, which were attributed to the effects of the intra-layer orientation and interlayer sliding, respectively.

Entropy measures, entropy estimators, and their performance in quantifying complex dynamics: Effects of artifacts, nonstationarity, and long-range correlations.

Entropy measures are widely applied to quantify the complexity of dynamical systems in diverse fields. However, the practical application of entropy methods is challenging, due to the variety of entropy measures and estimators and the complexity of real-world time series, including nonstationarities and long-range correlations (LRC). We conduct a systematic study on the performance, bias, and limitations of three basic measures (entropy, conditional entropy, information storage) and three traditionally used estimators (linear, kernel, nearest neighbor). We investigate the dependence of entropy measures on estimator- and process-specific parameters, and we show the effects of three types of nonstationarities due to artifacts (trends, spikes, local variance change) in simulations of stochastic autoregressive processes. We also analyze the impact of LRC on the theoretical and estimated values of entropy measures. Finally, we apply entropy methods on heart rate variability data from subjects in different physiological states and clinical conditions. We find that entropy measures can only differentiate changes of specific types in cardiac dynamics and that appropriate preprocessing is vital for correct estimation and interpretation. Demonstrating the limitations of entropy methods and shedding light on how to mitigate bias and provide correct interpretations of results, this work can serve as a comprehensive reference for the application of entropy methods and the evaluation of existing studies.

Facile construction of the pentacyclic framework of subincanadine B. Synthesis of 20-deethylenylated subincanadine B and 19,20-dihydrosubincanadine B.

[reaction: see text] We describe a facile approach for effectively constructing the pentacyclic framework of subincanadine B. The seven-step assembly of tetracyclic ketone 14 featured Michael addition, Pictet-Spengler cyclization, and Dieckmann condensation. From this key ketone intermediate, two analogues of subincanadine B, i.e., 20-deethylenylated subincanadine B (27) and 19,20-dihydrosubincanadine B (31), were synthesized in four steps, respectively.