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Virtual Reality (VR) is an evolving wearable technology across many domain applications, including health delivery. Yet, human physiological adoption of VR technology is limited by cybersickness (CS) - a debilitating sensation accompanied by a cluster of symptoms, including nausea, oculomotor issues and dizziness. A leading problem is the lack of automated objective tools to predict or detect CS in individuals, which can then be used for resistance training, timely warning systems or clinical intervention. This paper explores the spatiotemporal brain dynamics and heart rate variability involved in cybersickness, and uses this information to both predict and detect CS episodes. The present study applies deep learning of EEG in a spiking neural network (SNN) architecture with a fusion of sympathetic heart rate variability parameters to predict CS prior to using VR (77.5%) and detect it (75.0%), which is more accurate than using just EEG (75%, 70.3%) or ECG alone (74.2%, 72.6%). The study found that Cz (premotor and supplementary motor cortex) and O2 (primary visual cortex) are key hubs in functionally connected networks associated with both CS events and susceptibility to CS. Consequently, Cz and O2 are presented here as promising targets for therapeutic interventions to alleviate and/or prevent the cybersickness.

Four polyketide-amino acid derivatives, pardinumones A-D (1-4), were isolated from the wild mushroom Tricholoma pardinum. Their structures together with absolute configurations were characterized by means of spectroscopic data analyses, as well as calculated electronic circular dichroism (ECD) and NMR with sorted training set (STS) protocol analysis. Compounds 1-4 exhibited antibacterial activity against Staphylococcus aureus, Staphylococcus epidermidis, and Escherichia coli with MIC values in the range of 6.25-50 μg/mL.

Background Studies have suggested that patients with inflammatory bowel disease (IBD) have an increased risk of rheumatoid arthritis (RA). However, the available data on this association are inconsistent. This meta-analysis aimed to determine the association between IBD and the risk of RA. Methods Observational studies investigating the RA risk among patients with IBD (Crohn disease (CD) and/or ulcerative colitis (UC)) were searched in PubMed, Embase, and Web of Science from the date of inception to December 2019. The methodological quality of the included studies was assessed using the Newcastle-Ottawa Scale. Relative risks (RRs) and corresponding 95% confidential intervals (CIs) were pooled with a random-effects model. Heterogeneity was evaluated using I2 statistics while publication bias was determined using Begg’s and Egger’s tests. Subgroup and sensitivity analyses were performed. Results A total of three cohort studies, three cross-sectional studies, and two case-control studies were included in the meta-analyses. Compared to the non-IBD control or general population, there was a significantly higher risk of RA among patients with IBD (RR = 2.59; 95% CI: 1.93–3.48). Moreover, both CD (RR = 3.14; 95% CI: 2.46–4.01) and UC (RR = 2.29; 95% CI: 1.76–2.97) were associated with a significantly increased risk of RA. However, heterogeneity was substantial across studies and the subgroup analyses failed to identify the potential source of heterogeneity. Conclusions Patients with IBD have a greater risk of developing RA. Rheumatologists should be consulted when patients with IBD present with undifferentiated joint complaints. However, more prospective cohort studies are needed to validate these results.

Seven previously undescribed trichothecenes, named trichothecrotocins M–S (1–7), along with five known compounds, were isolated from rice cultures of the potato-associated fungus Trichothecium crotocinigenum. Their structures and absolute configurations were determined through spectroscopic methods, single-crystal X-ray diffraction, and quantum chemistry calculations on ECD. Compound 1 possesses a rare 6,11-epoxy moiety in the trichothecene family. Compound 6 exhibited strong cytotoxic activity against MCF-7 cancer cell lines with an IC50 value of 2.34 ± 0.45 μM. It promoted apoptosis induction in MCF-7 cells. Moreover, cell cycle analysis showed cell cycle arrest caused by compound 6 at the G2/M phase which resulted to cell proliferation inhibition and pro-apoptotic activity. Further quantitative real-time PCR (qRT-PCR) analysis confirmed that the G2/M arrest was accompanied by upregulation of p21 and down regulation of cyclins B1 in 6-treated MCF-7 cells.

A new homoisoflavonoid, (3R)-5,7-dihydroxy-6-methyl-3-(2′-hydroxy-4′-methoxybenzyl)-chroman-4-one (1), namely polygonatone H, in addition to fourteen known homoisoflavones (2–15) were isolated from the rhizome of Polygonatum Cyrtonema Hua. The structures were identified with the aid of 1D/2D NMR spectroscopic technologies. Compounds 2, 6, 8, 10, 11, 13, and 15 were isolated from P. Cyrtonema for the first time. Compound 1 showed cytotoxicities to human cancer cell lines with IC50 values to comparable those of cisplatin.

S-shaped bend waveguides are indispensable in planar light circuits to realize the lateral displacements and connections. High-density integrated optical circuits require S-shaped bend waveguides to be low loss and compact sized. In this paper, the loss mechanism of the S-shaped bend is briefly analyzed first, and then a novel scheme to optimize the waveguide bends is proposed. Using a modified random direction method, the random orthogonal axial gradient method (ROAGM), the configuration curves of the S-shaped bends fitted by polynomials are optimized. Numerical results show that the insertion losses of the optimized configuration curves are much smaller than those of the conventional cosine functions when the space requirement is strict.

A new organic penta­borate, C4H7N2+·B5O6(OH)4−, has been synthesized under hydro­thermal conditions. Its crystal structure is composed of isolated penta­borate anions and 2-methyl­imidazolium counter-cations. The B5O6(OH)4− units are connected to one another through hydrogen bonds, forming a three-dimensional framework with large channels along the c axis, in which the cations are located.