Lightweight and Adaptive FDD Massive MIMO CSI Feedback with Deep Equilibrium Learning

In frequency-division duplexing (FDD) massive multiple-input multiple-output (MIMO) systems, downlink channel state information (CSI) needs to be sent from users back to the base station (BS), which causes prohibitive feedback overhead. In this paper, we propose a lightweight and adaptive deep learning-based CSI feedback scheme by capitalizing on deep equilibrium models. Different from existing deep learning-based approaches that stack multiple explicit layers, we propose an implicit equilibrium block to mimic the process of an infinite-depth neural network. In particular, the implicit equilibrium block is defined by a fixed-point iteration and the trainable parameters in each iteration are shared, which results in a lightweight model. Furthermore, the number of forward iterations can be adjusted according to the users' computational capability, achieving an online accuracy-efficiency trade-off. Simulation results will show that the proposed method obtains a comparable performance as the existing benchmarks but with much-reduced complexity and permits an accuracy-efficiency trade-off at runtime.Comment: submitted to IEEE for possible publicatio

Discriminatory Power Evaluation of Nuclear Ribosomal RNA Barcoding Sequences Through Ophiocordyceps sinensis Related Samples

Since the cost of Ophiocordyceps sinensis has increased dramatically and the counterfeits may have adverse effect to health, a rapid and precise species-level DNA barcoding identification system could be a potent approach and significantly enhance the regulatory capacity. The discrimination power of three subunits sequences from nuclear ribosomal RNA gene cluster were determined by Simpson’s index of discrimination using 43 wild O. sinensis fruiting bodies, pure cultures, commercial mycelium fermented powder and counterfeits. The internal transcribed spacer (ITS) sequences showed the highest variance and discrimination power among 43 samples, as determined by Simpson’s index of discrimination (D = 0.972), followed by large subunit (LSU; D = 0.963) and small subunit (SSU; D = 0.921). ITS-2 sequences showed the highest discrimination power for 43 samples among ITS-1, ITS-2, and 5.8S region of ITS sequences. All O. sinensis samples were grouped into a unique ITS sequence cluster under 95% similarity and two O. sinensis samples and six non-O. sinensis samples showed false claims. Our data showed that the ITS region could provide accurate species identification for O. sinensis samples, especially when macroscopic and microscopic method could not be applied in the highly processed commercial products. Since the authentication of O. sinensis related products is essential to ensure its safety and efficacy, identification of O. sinensis through ITS sequence comparison or unique PCR amplification of the species specific target, such as the ITS region, should be considered in the next revision of Chinese pharmacopeia

Malignant B Cells Induce the Conversion of CD4+CD25− T Cells to Regulatory T Cells in B-Cell Non-Hodgkin Lymphoma

Recent evidence has demonstrated that regulatory T cells (Treg) were enriched in the tumor sites of patients with B-cell non-Hodgkin lymphoma (NHL). However, the causes of enrichment and suppressive mechanisms need to be further elucidated. Here we demonstrated that CD4+CD25+FoxP3+CD127lo Treg were markedly increased and their phenotypes were different in peripheral blood (PB) as well as bone marrow (BM) from newly diagnosed patients with B-cell NHL compared with those from healthy volunteers (HVs). Involved lymphatic tissues also showed higher frequencies of Treg than benign lymph nodes. Moreover, the frequencies of Treg were significantly higher in involved lymphatic tissues than those from PB as well as BM in the same patients. Suppression mediated by CD4+CD25+ Treg co-cultured with allogeneic CFSE-labeled CD4+CD25− responder cells was also higher in involved lymphatic tissues from B-cell NHL than that mediated by Treg from HVs. In addition, we found that malignant B cells significantly induced FoxP3 expression and regulatory function in CD4+CD25− T cells in vitro. In contrast, normal B cells could not induce the conversion of CD4+CD25− T cells to Treg. We also showed that the PD-1/B7-H1 pathway might play an important role in Treg induction. Taken together, our results suggest that malignant B cells induce the conversion of CD4+CD25− T cells to Treg, which may play a role in the pathogenesis of B-cell NHL and represent a promising therapeutic target

Differential Gene Expression by RamA in Ciprofloxacin-Resistant Salmonella Typhimurium

Overexpression of ramA has been implicated in resistance to multiple drugs in several enterobacterial pathogens. In the present study, Salmonella Typhimurium strain LTL with constitutive expression of ramA was compared to its ramA-deletion mutant by employing both DNA microarrays and phenotype microarrays (PM). The mutant strain with the disruption of ramA showed differential expression of at least 33 genes involved in 11 functional groups. The study confirmed at the transcriptional level that the constitutive expression of ramA was directly associated with increased expression of multidrug efflux pump AcrAB-TolC and decreased expression of porin protein OmpF, thereby conferring multiple drug resistance phenotype. Compared to the parent strain constitutively expressing ramA, the ramA mutant had increased susceptibility to over 70 antimicrobials and toxic compounds. The PM analysis also uncovered that the ramA mutant was better in utilization of 10 carbon sources and 5 phosphorus sources. This study suggested that the constitutive expression of ramA locus regulate not only multidrug efflux pump and accessory genes but also genes involved in carbon metabolic pathways

Real-time Monitoring for the Next Core-Collapse Supernova in JUNO

Core-collapse supernova (CCSN) is one of the most energetic astrophysical events in the Universe. The early and prompt detection of neutrinos before (pre-SN) and during the SN burst is a unique opportunity to realize the multi-messenger observation of the CCSN events. In this work, we describe the monitoring concept and present the sensitivity of the system to the pre-SN and SN neutrinos at the Jiangmen Underground Neutrino Observatory (JUNO), which is a 20 kton liquid scintillator detector under construction in South China. The real-time monitoring system is designed with both the prompt monitors on the electronic board and online monitors at the data acquisition stage, in order to ensure both the alert speed and alert coverage of progenitor stars. By assuming a false alert rate of 1 per year, this monitoring system can be sensitive to the pre-SN neutrinos up to the distance of about 1.6 (0.9) kpc and SN neutrinos up to about 370 (360) kpc for a progenitor mass of 30$M_{\odot}$ for the case of normal (inverted) mass ordering. The pointing ability of the CCSN is evaluated by using the accumulated event anisotropy of the inverse beta decay interactions from pre-SN or SN neutrinos, which, along with the early alert, can play important roles for the followup multi-messenger observations of the next Galactic or nearby extragalactic CCSN.Comment: 24 pages, 9 figure

CEO advice seeking: An integrative framework and future research agenda

In this paper, we review the burgeoning but dispersed literature on chief executive officer (CEO) advice seeking, which has important effects on strategic decision making, the CEO’s and the board of directors’ effectiveness, and firms’ entrepreneurial orientation, innovativeness, and financial performance. We synthesize research findings about the key features of CEO advice seeking and its antecedents and outcomes across multiple levels of analysis. On the basis of our review, we identify important research gaps and develop a future research agenda that outlines new research questions and empirical foci that extend the current scope of analysis. We also highlight promising new theories and underutilized methods suitable for this area of research. With an integrative review and research agenda, we hope to stimulate cross-fertilization of different lines of inquiry and encourage new research that shines a spotlight on the remaining puzzles of CEO advice-seeking research