Symbol-Level Selective Full-Duplex Relaying with Power and Location Optimization

In this paper, a symbol-level selective transmission for full-duplex (FD) relaying networks is proposed to mitigate error propagation effects and improve system spectral efficiency. The idea is to allow the FD relay node to predict the correctly decoded symbols of each frame, based on the generalized square deviation method, and discard the erroneously decoded symbols, resulting in fewer errors being forwarded to the destination node. Using the capability for simultaneous transmission and reception at the FD relay node, our proposed strategy can improve the transmission efficiency without extra cost of signalling overhead. In addition, targeting on the derived expression for outage probability, we compare it with half-duplex (HD) relaying case, and provide the transmission power and relay location optimization strategy to further enhance system performance. The results show that our proposed scheme outperforms the classic relaying protocols, such as cyclic redundancy check based selective decode-and-forward (S-DF) relaying and threshold based S-DF relaying in terms of outage probability and bit-error-rate. Moreover, the performances with optimal power allocation is better than that with equal power allocation, especially when the FD relay node encounters strong self-interference and/or it is close to the destination node.Comment: 34 pages (single-column), 14 figures, 2 tables, accepted pape

Conducción entre la vena pulmonar superior izquierda, la aurícula izquierda y la fibrilación auricular bajo el estímulo del tronco cervico-vagal

Objective: The effect of cervical vagal trunk stimulation on conduction between left superior pulmonary vein and left atria and atria fibrillation have not been systematically studied. We attempted to investigate the electrical conduction between LA and LSPV in dogs with cervical vagal trunk stimulation and evaluate the possible underline substrates for local reentry and initiation and maintenance of AF. Methods:12 mongrel dogs (18-25 kg) underwent cervical vagal trunk stimulation at high-frequency (60 ms, 1-4V) to produce sinus arrest lasting >2 seconds,complete atrioventricularAV blocking or the sinus rate decreasing more than 50%. Left lateral thoracotomy was performed and the heart was exposed in a pericardial cradle. The HRA, LAA, PV-LAJ, LSPVm and LSPVd was locally stimulated (100 ms, 2-8V). ERP of HRA, LAA, PV-LAJ and within LSPV, ERP heterogeneity within LSPV and conduction between left superior pulmonary vein and left atria and atrial fibrillation inducing rate with vagal response was analyzed. Results: 1. During cervical vagal stimulation, the heart rate was reduced significantly from baseline 156±34 bpm to 75±34 bpm (p<0.05, n=12), ERP of HRA, LAA, PV-LAJ, LSPVm and LSPVd sites was shortened locally in all animals, ERP heterogeneity (COV-ERP ) was increased from baseline 3±3% to 30±13% (on average, p<0.05; n=12) and inducibility of AF was increased from baseline 49.9% to 70.9% with S1S1stimulation (100 ms, 2-8V) and from baseline 3.7% to 43.5% with S1S2 (5 ms decremented stepwise S1S2 300/200 ms, 2-8V, n=12; 2. LA and PV potentials at LA, PV-LAJ, LSPVm and LSPVd was overlapped during sinus rate and separated remarkably by stimulating at distal part of LSPV (n=9); 3. Unidirectional and bi-directional conduction(n=9), bi-directional decremented conduction (n=6), delayed conduction from LSPVp to LSPVd (n=12) and slow conduction from stimulating signal to local tissue potential (n=9) before onset of AF were recorded by pacing from both LSPV and LA. Conclusion: Our study strongly suggested that fast ectopic beating, abnormal vagal nerve activation as well as remodeling conduction between left superior pulmonary vein and left atria might are the common underline substrates for local reentry and AF initiation and maintenance. Objetivo: El efecto del estímulo del tronco nervioso cervico-vagal sobre la conducción entre la vena pulmonar superior izquierda (LSPV, siglas en inglés), la aurícula izquierda (LA, siglas en inglés) y la fibrilación auricular (AF, siglas en inglés), no se ha estudiado sistemáticamente. Se intentó investigar la conducción eléctrica entre la LA y la LSPV, con el estímulo del tronco nervioso cervico-vagal y evaluar los posibles substratos subyacentes para la reentrada local, la iniciación y el mantenimiento de la AF. Métodos: En 12 perros sin raza (18-25 kg), se estimuló el tronco cervico-vagal con alta frecuencia (60ms, 1-4V) para producir detenimiento sinusal con duración >2 s, completo bloqueo atrio-ventricular (AV) o un descenso superior a 50% en el ritmo sinusal. Se hizo una toracotomía lateral izquierda y se expuso el corazón en la malla pericárdica. Los HRA, LAA, PV-LAJ, LSPVm y LSPVd se estimularon localmente (100 ms, 2-8V). El de HRA, LAA, PV-LAJ y dentro de la LSPV, la heterogeneidad dentro de la LSPV y la conducción entre la vena pulmonar superior izquierda, la aurícula izquierda y la fibrilación auricular que induce un ritmo con respuesta vagal, también se analizaron. Resultados: 1. Durante el estímulo vago-cervical, el ritmo cardíaco se redujo significativamente desde la línea basal 156±34 bpm a 75±34bpm (p<0.05, n=12); los sitios ERP de HRA, LAA, PV-LAJ, LSPVm y LSPVd se acortaron localmente en todos los animales. La heterogeneidad (COV-ERP) aumentó desde la línea basal 3±3% A 30±13% (en promedio, p<0.05, n012) y la capacidad de ser inducida la AF aumentó desde la línea base 49.8% a 70.9% con un estímulo S1S1 (100 ms, 2-8V) y desde la línea basal 3.7% a 43.5% con S1S2 5ms reducido paso a paso S1S2 300/200ms, 2-8V, n=12. 2. Los potenciales de la LA y la PV en LA, PV-LAJ, LSPVm y LSPVd, se sobrepusieron durante el ritmo sinusal y se separaron notablemente por el estímulo en la porción distal de LSPV (n=9). 3. La conducción uni-direccional y bi-direccional (=9), la conducción disminuida (n=6), la conducción retardada de LSPVp a LSPVD (n=12) y la conducción lenta desde la señal estímulo hasta el potencial tejido local (n=9), antes del comienzo de la AF se registraron paso a paso tanto desde la LSPV como desde la LA. Conclusión: Este estudio sugirió con mucho vigor que los latidos ectópicos, la activación anormal del vago, así como la conducción remodelante entre la vena pulmonar superior izquierda y la aurícula izquierda son substratos comunes subyacentes para el reingreso local, la iniciación y el mantenimiento de la fibrilación auricular

Human Primordial Germ Cells Are Specified from Lineage-Primed Progenitors.

In vitro gametogenesis is the process of making germline cells from human pluripotent stem cells. The foundation of this model is the quality of the first progenitors called primordial germ cells (PGCs), which in vivo are specified during the peri-implantation window of human development. Here, we show that human PGC (hPGC) specification begins at day 12 post-fertilization. Using single-cell RNA sequencing of hPGC-like cells (hPGCLCs) differentiated from pluripotent stem cells, we discovered that hPGCLC specification involves resetting pluripotency toward a transitional state with shared characteristics between naive and primed pluripotency, followed by differentiation into lineage-primed TFAP2A+ progenitors. Applying the germline trajectory to TFAP2C mutants reveals that TFAP2C functions in the TFAP2A+ progenitors upstream of PRDM1 to regulate the expression of SOX17. This serves to protect hPGCLCs from crossing the Weismann's barrier to adopt somatic cell fates and, therefore, is an essential mechanism for successfully initiating in vitro gametogenesis

Application of PBL pedagogy based on virtual reality technology in the teaching of sports anatomy

Purposes To explore the teaching effect and value of virtual reality technology combined with PBL teaching method applied to sports anatomy. Procedures 119 undergraduate students majoring in physical education of Xianyang Normal University were selected as research objects. Randomly divided into experimental group (N=59) and control group (N=60). Methods The experimental group used virtual reality technology combined with PBL teaching method, and the control group used traditional teaching method to teach. At the end of the course, the test scores of the two groups and the evaluation results of self-learning effect were statistically analyzed. Results the test scores of the students in the experimental group were significantly higher than those in the control group (P<0.05); Most of the items in which the experimental students self-evaluated the learning effectiveness were also superior to the control group (P< 0.05), and the difference was statistically significant. Conclusions VR technology combined with PBL teaching method can improve academic performance, enhance students’ learning interest and independent learning ability, and cultivate students’ ability to find and solve problems. It is a teaching method worth promoting

The single t-quark productions via the flavor-changing processes in the topcolor-assisted technicolor model at the hadron colliders

In the framework of topcolor-assisted technicolor(TC2) model, there exist tree-level flavor-changing (FC) couplings which can result in the loop-level FC coupling $tcg$. Such $tcg$ coupling can contribute significant clues at the forthcoming Large Hadron Collider (LHC) experiments. In this paper, based on the TC2 model, we study some single t-quark production processes involving $tcg$ coupling at the Tevatron and LHC: $pp(p\bar{p})\to t\bar{q}(q=u,d,s),tg$. We calculate the cross sections of these processes. The results show that the cross sections at the Tevatron are too small to observe the signal, but at the LHC it can reach a few pb. With the high luminosity, the LHC has considerable capability to find the single t-quark signal produced via some FC processes involving coupling $tcg$. On the other hand, these processes can also provide some valuable information of the coupling $tcg$ with detailed study of the processes and furthermore provide the reliable evidence to test the TC2 model.Comment: 15 pages, 10 figure

T cell immunity rather than antibody mediates cross-protection against Zika virus infection conferred by a live attenuated Japanese encephalitis SA14-14-2 vaccine.

Zika virus (ZIKV) and Japanese encephalitis virus (JEV) are closely related to mosquito-borne flaviviruses. Japanese encephalitis (JE) vaccine SA14-14-2 has been in the Chinese national Expanded Program on Immunization since 2007. The recent recognition of severe disease syndromes associated with ZIKV, and the identification of ZIKV from mosquitoes in China, prompts an urgent need to investigate the potential interaction between the two. In this study, we showed that SA14-14-2 is protective against ZIKV infection in mice. JE vaccine SA14-14-2 triggered both Th1 and Th2 cross-reactive immune responses to ZIKV; however, it was cellular immunity that predominantly mediated cross-protection against ZIKV infection. Passive transfer of immune sera did not result in significant cross-protection but did mediate antibody-dependent enhancement in vitro, though this did not have an adverse impact on survival. This study suggests that the SA14-14-2 vaccine can protect against ZIKV through a cross-reactive T cell response. This is vital information in terms of ZIKV prevention or precaution in those ZIKV-affected regions where JEV circulates or SA14-14-2 is in widespread use, and opens a promising avenue to develop a novel bivalent vaccine against both ZIKV and JEV. KEY POINTS: • JEV SA14-14-2 vaccine conferred cross-protection against ZIKV challenge in mice. • T cell immunity rather than antibody mediated the cross-protection. • It provides important information in terms of ZIKV prevention or precaution

Feasible pickup from intact ossicular chain with floating piezoelectric microphone

<p>Abstract</p> <p>Objectives</p> <p>Many microphones have been developed to meet with the implantable requirement of totally implantable cochlear implant (TICI). However, a biocompatible one without destroying the intactness of the ossicular chain still remains under investigation. Such an implantable floating piezoelectric microphone (FPM) has been manufactured and shows an efficient electroacoustic performance in vitro test at our lab. We examined whether it pick up sensitively from the intact ossicular chain and postulated whether it be an optimal implantable one.</p> <p>Methods</p> <p>Animal controlled experiment: five adult cats (eight ears) were sacrificed as the model to test the electroacoustic performance of the FPM. Three groups were studied: (1) the experiment group (on malleus): the FPM glued onto the handle of the malleus of the intact ossicular chains; (2) negative control group (in vivo): the FPM only hung into the tympanic cavity; (3) positive control group (Hy-M30): a HiFi commercial microphone placed close to the site of the experiment ear. The testing speaker played pure tones orderly ranged from 0.25 to 8.0 kHz. The FPM inside the ear and the HiFi microphone simultaneously picked up acoustic vibration which recorded as .wav files to analyze.</p> <p>Results</p> <p>The FPM transformed acoustic vibration sensitively and flatly as did the in vitro test across the frequencies above 2.0 kHz, whereas inefficiently below 1.0 kHz for its overloading mass. Although the HiFi microphone presented more efficiently than the FPM did, there was no significant difference at 3.0 kHz and 8.0 kHz.</p> <p>Conclusions</p> <p>It is feasible to develop such an implantable FPM for future TICIs and TIHAs system on condition that the improvement of Micro Electromechanical System and piezoelectric ceramic material technology would be applied to reduce its weight and minimize its size.</p

Contextuality, decoherence and quantum trajectories

Here we analyze the relationship between quantum contextuality and decoherence in interference experiments with matter particles by means of a simple reduced quantum-trajectory model, which attempts to simulate the behavior of the projections of multi-dimensional, system-plus-environment Bohmian trajectories onto the subspace of the reduced system. This model allows us to understand the crossing of the subsystem trajectories as a combined effect of interference quenching and erasure of ``which-way'' information, which can be of utility to interpret decoherence effects in many-dimensional systems where full Bohmian treatments become prohibitive computationally.Comment: 15 pages, 3 figure