Can Electromagnetic Information Theory Improve Wireless Systems? A Channel Estimation Example

Electromagnetic information theory (EIT) is an emerging interdisciplinary subject that integrates classical Maxwell electromagnetics and Shannon information theory. The goal of EIT is to uncover the information transmission mechanisms from an electromagnetic (EM) perspective in wireless systems. Existing works on EIT are mainly focused on the analysis of degrees-of-freedom (DoF), system capacity, and characteristics of the electromagnetic channel. However, these works do not clarify how EIT can improve wireless communication systems. To answer this question, in this paper, we provide a novel demonstration of the application of EIT. By integrating EM knowledge into the classical MMSE channel estimator, we observe for the first time that EIT is capable of improving the channel estimation performace. Specifically, the EM knowledge is first encoded into a spatio-temporal correlation function (STCF), which we term as the EM kernel. This EM kernel plays the role of side information to the channel estimator. Since the EM kernel takes the form of Gaussian processes (GP), we propose the EIT-based Gaussian process regression (EIT-GPR) to derive the channel estimations. In addition, since the EM kernel allows parameter tuning, we propose EM kernel learning to fit the EM kernel to channel observations. Simulation results show that the application of EIT to the channel estimator enables it to outperform traditional isotropic MMSE algorithm, thus proving the practical values of EIT.Comment: Electromagnetic information theory (EIT) is an emerging interdisciplinary subject, aiming at providing a unified analytical framework for wireless systems as well as guiding practical system design. This paper answers the question: "How can we improve wireless communication systems via EIT"

Human milk macronutrients and bioactive molecules and development of regional fat depots in Western Australian infants during the first 12 months of lactation

We investigated associations between intakes of human milk (HM) components (macronutrients and biologically active molecules) and regional fat depots development in healthy term infants (n = 20) across the first year of lactation. Infant limb (mid-arm and mid-thigh) lean and fat areas were assessed by ultrasound imaging at 2, 5, 9 and 12 months of age. Concentrations of HM total protein, whey protein, casein, adiponectin, leptin, lysozyme, lactoferrin, secretory IGA, total carbohydrates, lactose, HM oligosaccharides (total HMO, calculated) and infant 24-h milk intake were measured, and infant calculated daily intakes (CDI) of HM components were determined. This pilot study shows higher 24-h milk intake was associated with a larger mid-arm fat area (p = 0.024), higher breastfeeding frequency was associated with larger mid-arm (p = 0.008) and mid-thigh (p < 0.001) fat areas. Lysozyme (p = 0.001) and HMO CDI (p = 0.004) were time-dependently associated with the mid-arm fat area. Intakes of HM components and breastfeeding parameters may modulate infant limb fat depots development during the first year of age and potentially promote favorable developmental programming of infant body composition; however, further studies are needed to confirm these findings

Contamination of Proteus mirabilis harbouring various clinically important antimicrobial resistance genes in retail meat and aquatic products from food markets in China

Proteus mirabilis is an opportunistic pathogen frequently associated with nosocomial infection and food poisoning cases. Contamination of P. mirabilis in retail meat products may be important transmission routes for human infection with P. mirabilis. In this study a total of 89 P. mirabilis strains were isolated from 347 samples in 14 food markets in China and subjected to whole-genome sequencing. Phylogenetic analysis showed that all 89 strains were divided into 81 different clones (SNPs &gt;5), indicating high genetic diversity of P. mirabilis in food markets. Antimicrobial susceptibility testing showed that 81 (91.01%) strains displayed multidrug resistance profiles. Seventy-three different resistance genes (or variants) were found, including various clinically important antimicrobial resistance genes aac(6′)-Ib-cr (77.53%), blaCTX-M (39.33%), fosA3 (30.34%), as well as multiresistance gene cfr (4.50%), tigecycline resistance gene cluster tmexCD3-toprJ1 (4.50%) and carbapenemase gene blaNDM-1 (1.12%). Diverse genetic elements including Tn7 transposon, plasmid, SXT/R391 integrative conjugative element were associated with the horizontal transfer of cfr. tmexCD3-toprJ1 and blaNDM-1 were located on ICEPmiChnJZ26 and Salmonella genomic island 1, respectively. Our study emphasized high contamination of P. mirabilis harbouring various clinically important antimicrobial resistance genes in retail meat and aquatic products, which might be an important issue in terms of food safety and human health

The oncogene AAMDC links PI3K-AKT-mTOR signaling with metabolic reprograming in estrogen receptor-positive breast cancer

Adipogenesis associated Mth938 domain containing (AAMDC) represents an uncharacterized oncogene amplified in aggressive estrogen receptor-positive breast cancers. We uncover that AAMDC regulates the expression of several metabolic enzymes involved in the one-carbon folate and methionine cycles, and lipid metabolism. We show that AAMDC controls PI3K-AKT-mTOR signaling, regulating the translation of ATF4 and MYC and modulating the transcriptional activity of AAMDC-dependent promoters. High AAMDC expression is associated with sensitization to dactolisib and everolimus, and these PI3K-mTOR inhibitors exhibit synergistic interactions with anti-estrogens in IntClust2 models. Ectopic AAMDC expression is sufficient to activate AKT signaling, resulting in estrogen-independent tumor growth. Thus, AAMDC-overexpressing tumors may be sensitive to PI3K-mTORC1 blockers in combination with anti-estrogens. Lastly, we provide evidence that AAMDC can interact with the RabGTPase-activating protein RabGAP1L, and that AAMDC, RabGAP1L, and Rab7a colocalize in endolysosomes. The discovery of the RabGAP1L-AAMDC assembly platform provides insights for the design of selective blockers to target malignancies having the AAMDC amplification

One-dimensional leaky-wave antenna producing multiple beams

In this paper, far-field pattern of one-dimensional leaky-wave antenna (LWA) is directly synthesized by sinusoidally modulating surface currents of the antenna. Due to the characteristic of light cone in distinguishing surface waves and radiation waves, the numbers of the beams are selectable depending on the modulations. A one-dimensional substrate integrated waveguide (SIW) antenna producing two beams are designed and fabricated. Measurements agree very well with the simulations, indicating the validity of the presented synthesizing method as well as the practicalities of the presented SIW antenna

Development of a global high-resolution marine dynamic environmental forecasting system

A project entitled ‘Development of a Global High-resolution Marine Dynamic Environmental Forecasting System’ has been funded by ‘The Program on Marine Environmental Safety Guarantee’ of The National Key Research and Development Program of China. This project will accomplish its objectives through basic theoretical research, model development and expansion, and system establishment and application, with a focus on four key issues separated into nine tasks. A series of research achievements have already been obtained, including datasets, observations, theories, and model results

Planar bifunctional Luneburg-fisheye lens made of an anisotropic metasurface

Luneburg lens and Maxwell-fisheye lens are well-known microwave and optical devices with distinct focusing properties. Here, a planar bifunctional Luneburg-fisheye lens made of an anisotropic metasurface is presented, which features as a Luneburg along the horizontal optical axis, while as a fisheye along the vertical optical axis. A method to control the inhomogeneous indices of refraction along the two optical axes independently is proposed by designing an anisotropic and nonuniform metasurface, which can provide the required distributions of refractive indices approximately for Luneburg and fisheye lenses viewing from the two optical axes. Experiments in the microwave frequency range demonstrate very good performance of the planar bifunctional Luneburg-fisheye lens. The proposed method opens up an avenue to design other kinds of bifunctional devices using metasurfaces in the microwave, terahertz, and even optical ranges.Accepted versio

Impacts of Liquid Level on Microwave Resonance Sensing with a Flexible Microfluidic Channel

Abstract Permittivity sensing based on resonance tracking lays the fundamental principle for a variety of biochemical sensors, which has found vast applications in cancer biomarker detection, antigen‐antibody analysis, and so on. Driven by continuous promotion of the detection limit, precise environmental control highlights its critical importance. Here, the impacts of liquid level on microwave resonance sensing are investigated, in which a flexible polydimethylsiloxane microfluidic channel and soft tubing are employed to control the liquid under test. The hydraulic pressure affects the effective permittivity of the liquid and the channel material, hence causing extra resonance shift signals. Both contactless and contacting sensing scenarios are studied in numerical simulations and experiments. It is demonstrated that the resonance frequency varies sensitively with the liquid level, and a sensitivity of 343 kHz mm−1 is measured. Meanwhile, a spoof localized surface plasmon resonator and its optimized excitation structure are employed and analyzed for a good figure of merit, addressing the detectability difficulties for high‐permittivity and high‐loss aqueous solutions. These results provide general guidelines for understanding and controlling the resonance sensors in aqueous environments and help to realize further lower detection limits