Performance of Joint Channel and Physical Network Coding Based on Alamouti STBC

This work considers the protograph-coded physical network coding (PNC) based on Alamouti space-time block coding (STBC) over Nakagami-fading two-way relay channels, in which both the two sources and relay possess two antennas. We first propose a novel precoding scheme at the two sources so as to implement the iterative decoder efficiently at the relay. We further address a simplified updating rule of the log-likelihood-ratio (LLR) in such a decoder. Based on the simplified LLR-updating rule and Gaussian approximation, we analyze the theoretical bit-error-rate (BER) of the system, which is shown to be consistent with the decoding thresholds and simulated results. Moreover, the theoretical analysis has lower computational complexity than the protograph extrinsic information transfer (PEXIT) algorithm. Consequently, the analysis not only provides a simple way to evaluate the error performance but also facilitates the design of the joint channel-and-PNC (JCNC) in wireless communication scenarios.Comment: 6 pages, 4 figures, accpete

2-(Dibromo­meth­yl)benzoic acid

In the crystal structure of the title compound, C8H6Br2O2, the carboxyl groups are involved in pairs of O—H⋯O hydrogen bonds, which link the mol­ecules into inversion dimers

Endocytic recycling and vesicular transport systems mediate transcytosis of Leptospira interrogans across cell monolayer.

Many bacterial pathogens can cause septicemia and spread from the bloodstream into internal organs. During leptospirosis, individuals are infected by contact with Leptospira-containing animal urine-contaminated water. The spirochetes invade internal organs after septicemia to cause disease aggravation, but the mechanism of leptospiral excretion and spreading remains unknown. Here, we demonstrated that Leptospira interrogans entered human/mouse endothelial and epithelial cells and fibroblasts by caveolae/integrin-β1-PI3K/FAK-mediated microfilament-dependent endocytosis to form Leptospira (Lep)-vesicles that did not fuse with lysosomes. Lep-vesicles recruited Rab5/Rab11 and Sec/Exo-SNARE proteins in endocytic recycling and vesicular transport systems for intracellular transport and release by SNARE-complex/FAK-mediated microfilament/microtubule-dependent exocytosis. Both intracellular leptospires and infected cells maintained their viability. Leptospiral propagation was only observed in mouse fibroblasts. Our study revealed that L. interrogans utilizes endocytic recycling and vesicular transport systems for transcytosis across endothelial or epithelial barrier in blood vessels or renal tubules, which contributes to spreading in vivo and transmission of leptospirosis

Gender-Differential Associations between Attention Deficit and Hyperactivity Symptoms and Youth Health Risk Behaviors

Attention deficit and hyperactivity disorder (ADHD) is one of the common developmental disorders that generally receives clinical attention at learning ages, and some symptoms may persist in young adulthood.1 Past research has demonstrated a consistent association between ADHD and youth health risk behaviors (e.g., cigarette smoking), which often develop during adolescence and contribute to early morbidity and mortality among young adults.2 However, ADHD symptoms are not routinely screened in adolescents and emerging adults during their visits to healthcare providers.3 The six-item Adult Self-Report Scale (ASRS-6) for ADHD has been validated in the young population for screening purposes.4 This short form is time-saving and also provides a comparable predictivity of ADHD diagnosis as that of the original long version.5 Although accumulating evidence has demonstrated the association between ADHD symptoms and youth health risk behaviors, this issue has scarcely been explored in the Taiwanese youth population.6 Therefore, this study was conducted to validate the psychometric property of the Chinese version of ASRS-6 and examine the gender-stratified association between ADHD symptoms and youth health risk behaviors