A variety of industrial applications are deployed in underground environments, such as soil condition assessment and pipeline monitoring (PM). Wireless underground sensor networks (WUSNs) are capable ...of continuously monitoring pipelines and promptly alerting any anomaly of entities. However, underground soils significantly influence the traditional WUSNs connectivity success. Long range (LoRa), being a leading low-power wide-area networks (LPWANs) technology, provides a new solution for underground industrial monitoring with its advantages in long-range capability and ultralow power consumption. Nevertheless, the LoRa-based link quality characteristics have not yet been quantitatively evaluated for WUSNs. In this article, the channel models of both the underground-to-aboveground (UG2AG) and aboveground-to-underground (AG2UG) communications are investigated. We experimentally analyze the impact of the propagation direction, burial depth and LoRa physical layer parameters on the in-situ LoRa propagation performance. The received signal strength indictor (RSSI), signal-to-noise ratio (SNR), and packet deliver ratio (PDR) are characterized for both communication channels in LoRa-based WUSNs. The semiempirical path-loss models are successfully verified by our field results, and we demonstrate that the communication range can be greater than 50 m at the burial depth of 0.4 m by adjusting the LoRa transmission/receiving settings. The combination of RSSI and SNR can be a better indicator of PDR than relying on either of them alone. Finally, the frame error rate (FER) is calculated to estimate the link performance with EM interferences. These results successfully demonstrate the advantages of LoRa for PM applications, which serve the first step toward the efficient protocol development of LoRa-based WUSNs.
Abstract The repeated fast radio bursts FRB 121102A and FRB 190520B have been reported, along with a spatially coincident, compact, persistent radio emission. In this paper, we present a ...parameterized one-zone model, with the basic scenario that a relativistic magnetized wind from the pulsar sweeps up the surroundings, e.g., freely expanding supernova ejecta, giving rise to a power-law distribution of electrons between the forward shock and the termination shock. We show that via appropriate adjustment of the model parameters, we can obtain synchrotron radio emission properties from the one-zone model bright enough to account for the observation, simply and analytically fitting the observed spectra well. Through dynamical evolution of the model, we can also obtain time-varying relevant properties. This parameterized model does not depend on concrete physical models such as a central engine; instead, we can constraint the physical model via comparison between parameters and observations, indicating the information about the central engine and surroundings. We also discuss the synchrotron self-Compton emission in our scenario in the end but find no clue about the counterparts at other wave bands.
Despite exceptional experimental efforts to map out the human interactome, the continued data incompleteness limits our ability to understand the molecular roots of human disease. Computational tools ...offer a promising alternative, helping identify biologically significant, yet unmapped protein-protein interactions (PPIs). While link prediction methods connect proteins on the basis of biological or network-based similarity, interacting proteins are not necessarily similar and similar proteins do not necessarily interact. Here, we offer structural and evolutionary evidence that proteins interact not if they are similar to each other, but if one of them is similar to the other's partners. This approach, that mathematically relies on network paths of length three (L3), significantly outperforms all existing link prediction methods. Given its high accuracy, we show that L3 can offer mechanistic insights into disease mechanisms and can complement future experimental efforts to complete the human interactome.
Abstract In this paper, the potential of a broadband metasurface for ground penetrating radar (GPR) signal enhancement is investigated by simulation and experiments. Simulation results show that the ...reflection at the air-MUT interface can be reduced from 35% to 5% over a broad frequency range (relative bandwidth up to 44%) when the broadband metasurface is in place. Measured reflectance is consistent with the simulation results. Meanwhile, the electric field strength measurement results demonstrate that the transmitted electromagnetic signals can be amplified when the reflection is reduced over the same frequency range. GPR experiments verified that clear hyperbolic signals emerged for commonly undetectable pipes when the high-frequency signals are enhanced. The proposed broadband metasurface can be an effective solution for the detection of nonmetallic inclusions in high-lossy media.
Wireless underground sensor networks (WUSNs) have been preliminarily applied in underground infrastructure monitoring (UIM) to alert entities about any anomaly in a timely manner. Some key repeaters ...are deployed along a typical borehole to ensure reliable connectivity with the aboveground gateways. However, the link quality characteristics of the bi-directional communications between the underground repeaters and aboveground devices have not been experimentally analyzed for UIM-WUSNs. To this end, a semi-empirical evaluation of underground-to-aboveground (UG2AG) and aboveground-to-underground (AG2UG) communications are presented in non-backfilled scenarios. In this paper, the effects of burial depth, internode distance, propagation direction, and backfilled condition on link quality are quantitatively investigated by real-life experiments. First, the non-backfilled UG2AG and AG2UG channel model is proposed and verified by the measured data. Then, the symmetry between the UG2AG and AG2UG links is demonstrated in the non-backfilled communication. Finally, the backfilled UG2AG/AG2UG communications show asymmetry behavior, which is largely due to the channel sensitivity to the soil properties. These findings can provide guidelines for the design and development of new communication protocols in UIM-WUSNs.
Deeply buried inclusions such as pipes and cables cannot be detected when the air-ground interface suffers severe impedance mismatch, resulting in little electromagnetic (EM) signals penetrating the ...subsurface, even before the scattering and reflection from the buried inclusions occur. Therefore, increasing the penetration depth by effectively enhancing the EM transmission into the lossy subsurface domain is of great importance. In this article, we present our simulation and experimental results of a type of antireflection metasurfaces that can sufficiently enhance the transmission from the air to the subsurface for ground-penetrating radar (GPR) applications. The proposed metasurface design consists of an array of closed ring resonators (CRRs) and metallic mesh on each side of a dielectric spacer, showing near-perfect antireflection. The corresponding enhanced transmission is only limited by the material losses of the metasurface itself. Through the geometry optimizations, three metasurface designs have been numerically and experimentally demonstrated for the dry, medium moist, and wet scenarios. It is discovered that the transmission into the wet foam brick can be increased by up to 50% when the metasurface is in place. The metasurface-based transmission enhancement is also relatively insensitive to the deviation of the permittivity of the material under test (MUT). Our real-world GPR experiments demonstrate that an undetectable buried pipe can be distinguished if the metasurface is placed at the air-ground interface. The proposed metasurface approach provides a promising solution to the impedance matching problems for nondestructive testing applications.
Exosomes are small membrane particles which are widely found in various cell lines and physiological fluids in mammalian. MicroRNAs (miRNAs) enclosed in exosomes have been identified as proper ...signatures for many diseases and response to therapies. However, the composition of exosomes and enclosed miRNAs in fishes has not been investigated. Cynoglossus semilaevis is an important commercial flatfish with ambiguous distinction between males and females before sex maturation, which leads to screening difficulty in reproduction and cultivation. An effective detection method was required for sex differentiation of C. semilaevis. In this work, we successfully identified exosomes in C. semilaevis serum. The analysis of nucleotide composition showed that miRNA dominated in exosomes. Thereafter the miRNA profiles in exosomes from males and females were sequenced and compared to identify the signature miRNAs corresponding to sex differentiation. The functions of signature miRNAs were analyzed by target matching and annotation. Furthermore, 7 miRNAs with high expression in males were selected from signature miRNAs as the markers for sex identification with their expression profiles verified by real time quantitative PCR. Exosomes were first found in fish serum in this work. Investigation of marker miRNAs supplies an effective index for the filtration of male and female C. semilaevis in cultivation.
An iridium(III)‐catalyzed three‐component reaction of enamides, aryldiazonium tetrafluoroborates, and 1,4‐diazabicyclo2.2.2octane bis(sulfur dioxide) (DABSO) for the direct C(sp2)−H arylsulfonylation ...of enamides is developed. This transformation provides a robust and straightforward approach for preparing a diverse array of β‐amidovinyl sulfones in moderate to excellent yields and high stereoselectivities without Light‐emitting diode (LED) radiation. This transformation also features mild conditions, broad substrate scopes, and excellent functional group tolerance.
In this paper, an efficient plastic pipe detecting model is proposed, which combines the ground penetrating radar (GPR) and the electric field method. The model consists of the electric field ...locating model (EFLM) and the GPR B-scan image interpreting (GBII) model. Synchronized electric field and GPR data are collected through a data acquisition device dedicatedly designed for the swift and accurate estimation of buried plastic pipes. The EFLM estimates the approximate locations of underground plastic pipes from the electric field data quickly, separates a GPR B-scan image into segments, keeps the segments that might contain hyperbolas, and discards the irrelevant ones. Then, the GBII model interprets the depth and radius of the buried pipe in the kept segments. Our numerical simulations and experiments prove that by utilizing the EFLM, the 1-D electric field data could be processed quickly and the GPR B-scan image could be segmented with part of irrelevant pixels discarded, while hyperbolas in the kept image segments could be automatically and accurately fitted. With our proposed model, the depth and radius of the buried pipes could be efficiently obtained.
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