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In the literature, machine learning (ML) has been implemented at the base station (BS) and user equipment (UE) to improve the precision of downlink channel state information (CSI). However, ML implementation at the UE can be infeasible for various reasons, such as UE power consumption. Motivated by this issue, we propose a CSI learning mechanism at BS, called CSILaBS, to avoid ML at UE. To this end, by exploiting channel predictor (CP) at BS, a light-weight predictor function (PF) is considered for feedback evaluation at the UE. CSILaBS reduces over-the-air feedback overhead, improves CSI quality, and lowers the computation cost of UE. Besides, in a multiuser environment, we propose various mechanisms to select the feedback by exploiting PF while aiming to improve CSI accuracy. We also address various ML-based CPs, such as NeuralProphet (NP), an ML-inspired statistical algorithm. Furthermore, inspired to use a statistical model and ML together, we propose a novel hybrid framework composed of a recurrent neural network and NP, which yields better prediction accuracy than individual models. The performance of CSILaBS is evaluated through an empirical dataset recorded at Nokia Bell-Labs. The outcomes show that ML elimination at UE can retain performance gains, for example, precoding quality.

Reconfigurable intelligent surface (RIS) is envisioned as the key enabler of a smart wireless environment, offering a nearly energy-neutral solution to control the dynamic propagation of electromagnetic signals. On the other hand, channel prediction can bring promising benefits in various aspects of wireless systems, e.g., reducing channel state information feedback overhead. Prediction of a highly dynamic channel is cumbersome. This letter focuses on enhancing the performance of multiuser channel prediction by introducing time correlation in the composite channel while exploiting quasi-RIS. We show that the intelligently configured RIS improves channel prediction performance while saving sufficient RIS elements for other applications and simplifies machine learning architecture.

The metal thiophosphates (MTP), M2P2S6, are a versatile class of van der Waals materials, which are notable for the possibility of tuning their magnetic properties with the incorporation of different transition-metal cations. Further, they also offer opportunities to probe the independent and synergistic role of the magnetically active cation sublattice when coupled to P2Q6polyhedra. Herein, we report the structural, magnetic, and electronic properties of the series of MTPs, MnxCo2–xP2S6(x= 0.25, 0.5, 1, 1.5, 1.75) synthesized by the P2S5flux method. Structural and elemental analysis indicates a homogeneous stoichiometry in the MnxCo2–xP2S6compounds. We observe that a correlation is apparent between the intensities of specific Raman modes and Raman shifts with respect to the alloying ratio between Mn and Co. Magnetic susceptibility measurements indicate that the alloyed systems adopt an ordered antiferromagnetic (AFM) configuration with a dependence of the Néel temperature on the alloying ratio. A possible magnetic frustration behavior was observed for the composition MnCoP2S6due to magnetic moment compensation as the alloying ratio between Mn and Co approaches parity. Interestingly, mixed oxidation states of the metal cation species are also observed in MnxCo2–xP2S6along with a linear dependence of the work function on the alloying ratio of Mn and Co.

ABSTRACTBackground: No head-to-head studies are currently available comparing pneumococcal non-typeable Haemophilus influenzaeprotein D conjugate vaccine (PHiD-CV) with 13-valent pneumococcal conjugate vaccine (PCV-13). This study explored the feasibility of using network meta-analysis (NMA) to conduct an indirect comparison of the relative efficacy or effectiveness of the two vaccines.Methods: A systematic literature search was conducted for published randomized controlled trials (RCTs) and non-RCT studies reporting data on vaccine efficacy or effectiveness against invasive pneumococcal disease in children aged <5 years receiving 7-valent pneumococcal conjugate vaccine (PCV-7), PHiD-CV or PCV-13. Study quality was evaluated using published scales. NMA feasibility was assessed by considering whether a connected network could be constructed by examining published studies for differences in study or patient characteristics that could act as potential treatment effect modifiers or confounding variables.Results: A total of 26 publications were included; 2 RCTs (4 publications), 7 indirect cohort studies, and 14 case-control studies (15 publications). Study quality was generally good. The RCTs could not be connected in a network as there was no common comparator. The studies differed considerably in design, dose number, administration schedules, and subgroups analyzed. Reporting of exposure status and subject characteristics was inconsistent.Conclusion: NMA to compare the relative efficacy or effectiveness of PHiD-CV and PCV-13 is not feasible on the current evidence base, due to the absence of a connected network across the two RCTs and major heterogeneity between studies. NMA may be possible in future if sufficient RCTs become available to construct a connected network.

Molybdenum disulfide (MoS2), which is one of the representative transition metal dichalcogenides, can be made as an atomically thin layer while preserving its semiconducting characteristics. We fabricated single-, bi-, and multilayer MoS2field-effect transistor (FET) by the mechanical exfoliation method and studied the effect of deep ultraviolet (DUV) light illumination. The thickness of the MoS2layers was determined using an optical microscope and further confirmed by Raman spectroscopy and atomic force microscopy. The MoS2FETs with different number of layers were assessed for DUV-sensitive performances in various environments. The photocurrent response to DUV light becomes larger with increasing numbers of MoS2layers and is significantly enhanced in N2gas environment compared with that in atmospheric environment.

Interleukin‐4 (IL‐4) is a multifunctional cytokine, which is involved in numerous disease states, including atopic asthma. IL‐4 not only induces direct responses in cells but can also prime for secondary responses to stimuli. Little is known about the priming effects of IL‐4 on endothelial cells; therefore, we chose to examine the ability of IL‐4 to prime endothelial cells for platelet‐activating factor (PAF) synthesis and prostaglandin E2(PGE2) release. IL‐4 alone did not enhance PAF synthesis or PGE2release; however, pretreatment with IL‐4 primed for PAF synthesis and PGE2release in response to subsequent stimulation with histamine. In contrast, tumor necrosis factor α (TNF‐α), oncostatin M (OSM), and IL‐1β did not prime endothelial cells for PAF synthesis in response to histamine. The priming effects of IL‐4 occurred without any detectable changes in the requirement for signaling pathways upstream of PGE2release. IL‐4 treatment increased the expression of mRNA for histamine receptor 1 (HR1) and shifted the inhibition curve for pyrilamine, a specific HR1 antagonist. In addition, the dose‐response curve for histamine‐induced elevations in intracellular calcium was shifted following IL‐4 stimulation. Together, these data indicate that HR1 is up‐regulated in IL‐4‐stimulated human umbilical vein endothelial cells (HUVEC) and suggest that this up‐regulation may contribute to the enhanced responsiveness of IL‐4‐stimulated HUVEC to histamine.