JBRC: Jointly Balanced Routing and Charging Scheme for RF Energy Harvesting Wireless Sensor Networks

Chenyiming Wen,Bingqian Zhu,Yinan Zhu 한국통신학회 2020 한국통신학회 APNOMS Vol.2020 No.09

In radio frequency (RF) energy harvesting wireless sensor networks, employing a mobile charger (MC) is more cost-efficient and flexible to power the sensor nodes than deploying extensive stationary chargers. However, due to limited charging time of MC, the nodes’ residual energy distribution (i.e., energy balance degree) after charging will directly determine the lifetime of sensor networks. To promote the energy balance degree, two important problems required to solve are: how to determine the nodes’ routing scheme and how to schedule the MC to power the nodes. The two problems interact with each other. In this paper, we introduce a practical charging scenario, consider to combine the routing-based charging and charging-based routing, and propose a Jointly Balanced Routing and Charging (JBRC) scheme. Specifically, we propose a balanced routing strategy and a charging time allocation scheme, and iteratively jointly optimize them. Our goal is to achieve the energy balance in WSNs, i.e., maximizing the minimal residual energy among nodes. Additionally, the MC’s moving trajectory is selected and designed. From simulation experiments, we verify the superiority of our proposed JBRC scheme.

3D Printing of Bioinspired Structural Materials with Fibers Induced by Doctor Blading Process

Luquan Ren,Bingqian Li,Zhengyi Song,Qingping Liu,Lei Ren,Xueli Zhou 한국정밀공학회 2019 International Journal of Precision Engineering and Vol.6 No.1

Fiber is a crucial element in biological micro-structural materials. Replication of fiber-reinforced composites with analogous architectures of their natural counterparts has caused widespread academic concern. Recent researches indicate 3D printing technology has the potential to produce biomimetic structural materials. The aim of this study is to develop a process to fabricate fiber-reinforced composites with ordered yet spatially tunable fiber arrangement. Specifically, we present a method to align fibers during the 3D printing of fiber-reinforced composites. A modified slurry-based stereolithography process was developed, and the fibers in the fiber–resin mixture were aligned by Shear force produced during the spreading of slurry. We investigated the influence of relative factors on fiber orientation, and two models were used to uncover the internal mechanism. By controlling the speed and the direction of the moving blade, the patterns that fibers were arranged can be freely programmed. Therefore, we have extracted bioinspired sinusoidal and zigzag design motifs to analyze their mechanical properties compared with non-bioinspired motifs. The proposed method is relatively material agnostic, more efficient and more facile. It thus provides a promising route to fabricate fiber-reinforced composites, and has potential to be adopted in biological structures researches and industrial applications.

Temperature-dependent ferroelectric and piezoelectric response of Yb3+ and Tm3+ co-doped Ba0.95Ca0.05Ti0.90Zr0.10O3 lead-free ceramic

Yongshang Tian,Shuiyun Li,Bingqian Zhang,Yansheng Gong,Peng Liu,Xiongjie Hu,Qiangshan Jing 한양대학교 세라믹연구소 2022 Journal of Ceramic Processing Research Vol.23 No.4

The electrical properties of piezoelectric ceramics are temperature-dependent, which affects their potential for applications inenvironments with temperature variation. In this work, Yb3+ and Tm3+ co-doped Ba0.95Ca0.05Ti0.90Zr0.10O3 (BCTZ-YT) denselead-free ceramic was prepared using a modified polymeric precursor route. On the basis of structural and electricalmeasurements at various temperatures, the mechanism of a lack of oxygen vacancies, small structural defects, and small defectdipoles was deduced. This study reveals that the ferroelectricity and piezoelectricity are temperature-dependent, whereas thecapacitance is essentially unchanged with increasing temperature owing to the presence of a pure orthorhombic phase. Thecapacitance of the BCTZ-YT ceramic was essentially constant at ~4.5 nF, the thermal expansion coefficient was 8.57 × 10−6 K−1below 75 oC, and the piezoelectric response (d33*) was above 416 pm/V in a wide temperature range (-20 to 40 oC), suggestingthe results of this study are expected to inform future research.

Quickest Spectrum Sensing Approaches for Wideband Cognitive Radio Based On STFT and CS

( Qi Zhao ),( Wei Qiu ),( Boxue Zhang ),( Bingqian Wang ) 한국인터넷정보학회 2019 KSII Transactions on Internet and Information Syst Vol.13 No.3

This paper proposes two wideband spectrum sensing approaches: (i) method A, the cumulative sum (CUSUM) algorithm with short-time Fourier transform, taking advantage of the time-frequency analysis for wideband spectrum. (ii)method B, the quickest spectrum sensing with short-time Fourier transform and compressed sensing, shortening the time of perception and improving the speed of spectrum access or exit. Moreover, method B can take advantage of the sparsity of wideband signals, sampling in the sub-Nyquist rate, and it is more suitable for wideband spectrum sensing. Simulation results show that method A significantly outperforms the single serial CUSUM detection for small SNRs, while method B is substantially better than the block detection based spectrum sensing in small probability of the false alarm.

Incomplete autophagy promotes the replication of Mycoplasma hyopneumoniae

Wang Zhaodi,Wen Yukang,Zhou Bingqian,Tian Yaqin,Ning Yaru,Ding Honglei 한국미생물학회 2021 The journal of microbiology Vol.59 No.8

Autophagy is an important cellular homeostatic mechanism for recycling of degradative proteins and damaged organelles. Autophagy has been shown to play an important role in cellular responses to bacteria and bacterial replication. However, the role of autophagy in Mycoplasma hyopneumoniae infection and the pathogenic mechanism is not well characterized. In this study, we showed that M. hyopneumoniae infection significantly increases the number of autophagic vacuoles in host cells. Further, we found significantly enhanced expressions of autophagy marker proteins (LC3-II, ATG5, and Beclin 1) in M. hyopneumoniae-infected cells. Moreover, immunofluorescence analysis showed colocalization of P97 protein with LC3 during M. hyopneumoniae infection. Interestingly, autophagic flux marker, p62, accumulated with the induction of infection. Conversely, the levels of p62 and LC3-II were decreased after treatment with 3-MA, inhibiting the formation of autophagosomes, during infection. In addition, accumulation of autophagosomes promoted the expression of P97 protein and the survival of M. hyopneumoniae in PK- 15 cells, as the replication of M. hyopneumoniae was downregulated by adding 3-MA. Collectively, these findings provide strong evidence that M. hyopneumoniae induces incomplete autophagy, which in turn enhances its reproduction in host cells. These findings provide novel insights into the interaction of M. hyopneumoniae and host.

Removal of Chromium (Ⅵ) by Escherichia coli Cells Expressing Cytoplasmic or Surface-Displayed ChrB: a Comparative Study

( Xiaofeng Zhou ),( Jianghui Li ),( Weilong Wang ),( Fan Yang ),( Bingqian Fan ),( Chenlu Zhang ),( Xiaojun Ren ),( Feng Liang ),( Rong Cheng ),( Fengying Jiang ),( Huaibin Zhou ),( Juanjuan Yang ),( 한국미생물 · 생명공학회 2020 Journal of microbiology and biotechnology Vol.30 No.7

Various genetically engineered microorganisms have been developed for the removal of heavy metal contaminants. Metal biosorption by whole-cell biosorbents can be enhanced by overproduction of metal-binding proteins/peptides in the cytoplasm or on the cell surface. However, few studies have compared the biosorption capacity of whole cells expressing intracellular or surface-displayed metal-adsorbing proteins. In this study, several constructs were prepared for expressing intracellular and surface-displayed Ochrobactrum tritici 5bvl1 ChrB in Escherichia coli BL21(DE3) cells. E. coli cells expressing surface-displayed ChrB removed more Cr(VI) from aqueous solutions than cells with cytoplasmic ChrB under the same conditions. However, intracellular ChrB was less susceptible to variation in extracellular conditions (pH and ionic strength), and more effectively removed Cr(VI) from industrial wastewater than the surface-displayed ChrB at low pH (<3). An adsorptiondesorption experiment demonstrated that compared with intracellular accumulation, cell-surface adsorption is reversible, which allows easy desorption of the adsorbed metal ions and regeneration of the bioadsorbent. In addition, an intrinsic ChrB protein fluorescence assay suggested that pH and salinity may influence the Cr(VI) adsorption capacity of ChrB-expressing E. coli cells by modulating the ChrB protein conformation. Although the characteristics of ChrB may not be universal for all metal-binding proteins, our study provides new insights into different engineering strategies for whole-cell biosorbents for removing heavy metals from industrial effluents.

Encainide, a class Ic anti-arrhythmic agent, blocks voltage-dependent potassium channels in coronary artery smooth muscle cells

Hongliang Li,Yue Zhou,Yongqi Yang,Yiwen Zha,Bingqian Ye,Seo-Yeong Mun,Wenwen Zhuang,Jingyan Liang,Won Sun Park The Korean Society of Pharmacology 2023 The Korean Journal of Physiology & Pharmacology Vol.27 No.4

Voltage-dependent K⁺ (Kv) channels are widely expressed on vascular smooth muscle cells and regulate vascular tone. Here, we explored the inhibitory effect of encainide, a class Ic anti-arrhythmic agent, on Kv channels of vascular smooth muscle from rabbit coronary arteries. Encainide inhibited Kv channels in a concentration-dependent manner with an IC₅₀ value of 8.91 ± 1.75 μM and Hill coefficient of 0.72 ± 0.06. The application of encainide shifted the activation curve toward a more positive potential without modifying the inactivation curve, suggesting that encainide inhibited Kv channels by altering the gating property of channel activation. The inhibition by encainide was not significantly affected by train pulses (1 and 2 Hz), indicating that the inhibition is not use (state)-dependent. The inhibitory effect of encainide was reduced by pretreatment with the Kv1.5 subtype inhibitor. However, pretreatment with the Kv2.1 subtype inhibitor did not alter the inhibitory effects of encainide on Kv currents. Based on these results, encainide inhibits vascular Kv channels in a concentration-dependent and use (state)-independent manner by altering the voltage sensor of the channels. Furthermore, Kv1.5 is the main Kv subtype involved in the effect of encainide.

Molecular Orbital Gating Surface-Enhanced Raman Scattering

Guo, Chenyang,Chen, Xing,Ding, Song-Yuan,Mayer, Dirk,Wang, Qingling,Zhao, Zhikai,Ni, Lifa,Liu, Haitao,Lee, Takhee,Xu, Bingqian,Xiang, Dong American Chemical Society 2018 ACS NANO Vol.12 No.11

<P>One of the promising approaches to meet the urgent demand for further device miniaturization is to create functional devices using single molecules. Although various single-molecule electronic devices have been demonstrated recently, single-molecule optical devices which use external stimulations to control the optical response of a single molecule have rarely been reported. Here, we propose and demonstrate a field-effect Raman scattering (FERS) device with a single molecule, an optical counterpart to field-effect transistors (a key component of modern electronics). With our devices, the gap size between electrodes can be precisely adjusted at subangstrom accuracy to form single molecular junctions as well as to reach the maximum performance of Raman scattering via plasmonic enhancement. Based on this maximum performance, we demonstrated that the intensity of Raman scattering can be further enhanced by an additional ∼40% if the orbitals of the molecules bridged two electrodes were shifted by a gating voltage. This finding not only provides a method to increase the sensitivity of Raman scattering beyond the limit of plasmonic enhancement, but also makes it feasible to realize addressable functional FERS devices with a gate electrode array.</P> [FIG OMISSION]</BR>