Full-space Cloud of Random Points with a Scrambling Metasurface

Li, Zile,Dai, Qi,Mehmood, Muhammad Q.,Hu, Guangwei,yanchuk, Boris Luk’,Tao, Jin,Hao, Chenglong,Kim, Inki,Jeong, Heonyeong,Zheng, Guoxing,Yu, Shaohua,Alù,, Andrea,Rho, Junsuk,Qiu, Cheng-Wei Nature Publishing Group UK 2018 Light, science & applications Vol.7 No.1

<▼1><P>With the rapid progress in computer science, including artificial intelligence, big data and cloud computing, full-space spot generation can be pivotal to many practical applications, such as facial recognition, motion detection, augmented reality, etc. These opportunities may be achieved by using diffractive optical elements (DOEs) or light detection and ranging (LIDAR). However, DOEs suffer from intrinsic limitations, such as demanding depth-controlled fabrication techniques, large thicknesses (more than the wavelength), Lambertian operation only in half space, etc. LIDAR nevertheless relies on complex and bulky scanning systems, which hinders the miniaturization of the spot generator. Here, inspired by a Lambertian scatterer, we report a Hermitian-conjugate metasurface scrambling the incident light to a cloud of random points in full space with compressed information density, functioning in both transmission and reflection spaces. Over 4044 random spots are experimentally observed in the entire space, covering angles at nearly 90°. Our scrambling metasurface is made of amorphous silicon with a uniform subwavelength height, a nearly continuous phase coverage, a lightweight, flexible design, and low-heat dissipation. Thus, it may be mass produced by and integrated into existing semiconductor foundry designs. Our work opens important directions for emerging 3D recognition sensors, such as motion sensing, facial recognition, and other applications.</P></▼1><▼2><P><B>Metasurfaces: scrambling light for 3D detection and recognition</B></P><P>Firing light at a manufactured 'metasurface'—one carrying patterns at a smaller scale than the wavelength of the light—fills large volumes of space with defined points of light, potentially improving 3-D recognition and sensor applications. Cheng-Wei Qui and colleagues at the National University of Singapore, with co-workers across Asia and in the USA, created their unique metasurface from amorphous silicon. Light is scattered from and transmitted through the material to generate a cloud of data points in the surrounding space in which the structure and motion of objects under study can be analyzed. The initial development work with this “scrambling metasurface” suggests it could improve pattern recognition, including face recognition, motion detection and augmented reality applications. The researchers describe how their innovation overcomes significant limitations of existing methods in these fields.</P></▼2>

Preparation of Nanoflake Bi₂MoO₆ Photocatalyst Using CO(NH₂)₂ as Structure Orientation and Its Visible Light Degradation of Tetracycline Hydrochloride

Hu, Pengwei,Zheng, Dewen,Xian, Yuxi,Hu, Xianhai,Zhang, Qian,Wang, Shanyu,Li, Mingjun,Cheng, Congliang,Liu, Jin,Wang, Ping Materials Research Society of Korea 2021 한국재료학회지 Vol.31 No.6

Bi₂MoO₆ (BMO) via the structure-directing role of CO(NH₂)₂ is successfully prepared via a facile solvothermal route. The structure, morphology, and photocatalytic performance of the nanoflake BMO are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), fluorescence spectrum analysis (PL), UV-vis spectroscopy (UV-vis) and electrochemical test. SEM images show that the size of nanoflake BMO is about 50 ~ 200 nm. PL and electrochemical analysis show that the nanoflake BMO has a lower recombination rate of photogenerated carriers than particle BMO. The photocatalytic degradation of tetracycline hydrochloride (TC) by nanoflake BMO under visible light is investigated. The results show that the nanoflake BMO-3 has the highest degradation efficiency under visible light, and the degradation efficiency reached 75 % within 120 min, attributed to the unique hierarchical structure, efficient carrier separation and sufficient free radicals to generate active center synergies. The photocatalytic reaction mechanism of TC degradation on the nanoflake BMO is proposed.

Bending of a rectangular plate resting on a fractionalized Zener foundation

Cheng-Cheng Zhang,Hong-Hu Zhu,Bin Shi,Guo-Xiong Mei 국제구조공학회 2014 Structural Engineering and Mechanics, An Int'l Jou Vol.52 No.6

The long-term performance of plates resting on viscoelastic foundations is a major concern in the analysis of soil-structure interaction. As a powerful mathematical tool, fractional calculus may address these plate-on-foundation problems. In this paper, a fractionalized Zener model is proposed to study the time-dependent behavior of a uniformly loaded rectangular thin foundation plate. By use of the viscoelasticelastic correspondence principle and the Laplace transforms, the analytical solutions were obtained in termsof the Mittag-Leffler function. Through the analysis of a numerical example, the calculated plate deflection, bending moment and foundation reaction were compared to those from ideal elastic and standard viscoelastic models. It is found that the upper and lower bound solutions of the plate response estimated by the proposed model can be determined using the elastic model. Based on a parametric study, the impacts of model parameters on the long-term performance of a foundation plate were systematically investigated. The results show that the two spring stiffnesses govern the upper and lower bound solutions of the plate response. By varying the values of the fractional differential order and the coefficient of viscosity, the timedependent behavior of a foundation plate can be accurately captured. The fractional differential order seems to be dependent on the mechanical properties of the ground soil. A sandy foundation will have a small fractional differential order while in order to simulate the creeping of clay foundation, a larger fractional differential order value is needed. The fractionalized Zener model is capable of accounting for the primary and secondary consolidation processes of the foundation soil and can be used to predict the plateperformance over many decades of time.

Identification of Prostate Cancer LncRNAs by RNA-Seq

Hu, Cheng-Cheng,Gan, Ping,Zhang, Rui-Ying,Xue, Jin-Xia,Ran, Long-Ke Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.21

Purpose: To identify prostate cancer lncRNAs using a pipeline proposed in this study, which is applicable for the identification of lncRNAs that are differentially expressed in prostate cancer tissues but have a negligible potential to encode proteins. Materials and Methods: We used two publicly available RNA-Seq datasets from normal prostate tissue and prostate cancer. Putative lncRNAs were predicted using the biological technology, then specific lncRNAs of prostate cancer were found by differential expression analysis and co-expression network was constructed by the weighted gene co-expression network analysis. Results: A total of 1,080 lncRNA transcripts were obtained in the RNA-Seq datasets. Three genes (PCA3, C20orf166-AS1 and RP11-267A15.1) showed a significant differential expression in the prostate cancer tissues, and were thus identified as prostate cancer specific lncRNAs. Brown and black modules had significant negative and positive correlations with prostate cancer, respectively. Conclusions: The pipeline proposed in this study is useful for the prediction of prostate cancer specific lncRNAs. Three genes (PCA3, C20orf166-AS1, and RP11-267A15.1) were identified to have a significant differential expression in prostate cancer tissues. However, there have been no published studies to demonstrate the specificity of RP11-267A15.1 in prostate cancer tissues. Thus, the results of this study can provide a new theoretic insight into the identification of prostate cancer specific genes.

Age of Information of Two-way Data Exchanging System With Power-Splitting

Cheng Hu,Yunquan Dong 한국통신학회 2019 Journal of communications and networks Vol.21 No.3

We consider a two-way data exchanging system consistingof an access point and a smart device. The access point hasa constant power supply and the smart device does not. The accesspoint simultaneously transmits information and energy to thesmart device over block fading channels, with fixed powers Ptand Pt, respectively. The smart device receives data and energyat the same time, and stores the harvested energy in an energybuffer. Upon collecting enough energy, the smart device performsone block of transmission immediately. We investigate the timelinessand the efficiency of the system in terms of age of information(AoI) and data rate, respectively. We also investigate the trade-offbetween downlink communications and uplink communications byoptimizing the weighted-sum average AoI and weighted-sum datarate. Moreover, we present the optimal power-splitting ratio andthe optimal weighting coefficient w explicitly or via efficient algorithm.

Performance evaluation of soil-embedded plastic optical fiber sensors for geotechnical monitoring

Cheng-Cheng Zhang,Hong-Hu Zhu,Bin Shi,Jun-Kuan She,Dan Zhang 국제구조공학회 2016 Smart Structures and Systems, An International Jou Vol.17 No.2

Based on the distributed fiber optic sensing (DFOS) technique, plastic optical fibers (POFs) are attractive candidates to measure deformations of geotechnical structures because they can withstand large strains before rupture. Understanding the mechanical interaction between an embedded POF and the surrounding soil or rock is a necessary step towards establishing an effective POF-based sensing system for geotechnical monitoring. This paper describes a first attempt to evaluate the feasibility of POF-based soil deformation monitoring considering the POF–soil interfacial properties. A series of pullout tests were performed under various confining pressures (CPs) on a jacketed polymethyl methacrylate (PMMA) POF embedded in soil specimens. The test results were interpreted using a fiber–soil interaction model, and were compared with previous test data of silica optical fibers (SOFs). The results showed that the range of CP in this study did not induce plastic deformation of the POF; therefore, the POF–soil and the SOF–soil interfaces had similar behavior. CP was found to play an important role in controlling the fiber–soil interfacial bond and the fiber measurement range. Moreover, an expression was formulated to determine whether a POF would undergo plastic deformation when measuring soil deformation. The plasticity of POF may influence the reliability of measurements, especially for monitored geo-structures whose deformation would alternately increase and decrease. Taken together, these results indicate that in terms of the interfacial parameters studied here the POF is feasible for monitoring soil deformation as long as the plastic deformation issue is carefully addressed.

Two New Phenolic Glycosides from Hypoxis aurea Lour

Cheng, Zhong-Quan,Yang, Dan,Liu, Yu-Qing,Hu, Jiang-Miao,Jiang, He-Zhong,Wang, Peng-Cheng,Li, Ning,Zhou, Jun,Zhao, You-Xing Korean Chemical Society 2009 Bulletin of the Korean Chemical Society Vol.30 No.10

Organic Thin-Film-Transistor Arrays for Active-Matrix Display on Flexible Substrate

Cheng-Chung Lee,Hsiang-Yuan Cheng,Jia-Chong Ho,Tarng-Shiang Hu 한국물리학회 2006 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.48 No.I

Differently from a traditional inorganic transistor, the organic thin-film transistor can be fabricated at low temperature, so we can choose a light, thin, and cheap plastic substrate to replace glass substrate. Here, an organic thin-film transistor (OTFT) has been formed on plastic substrate. An active-matrix back plate with 64 × 128 pixels has been fabricated to drive a TNLCD. We achieved a field-effect mobility of 0.03 cm2/V·s and on/off current ratio of about 105 for the pentacene OTFT on plastic substrate. Besides vacuum deposition, these properties offer potential methods to fabricate OTFT on flat panel displays, such as spin coating, ink-jet printing, and even a roll-to-roll process.

MiR-1224-5p modulates osteogenesis by coordinating osteoblast/osteoclast differentiation via the Rap1 signaling target ADCY2

Hu Liangcong,Xie Xudong,Xue Hang,Wang Tiantian,Panayi Adriana C.,Lin Ze,Xiong Yuan,Cao Faqi,Yan Chengcheng,Chen Lang,Cheng Peng,Zha Kangkang,Sun Yun,Liu Guodong,Yu Chenyan,Hu Yiqiang,Tao Ranyang,Zhou 생화학분자생물학회 2022 Experimental and molecular medicine Vol.54 No.-

MicroRNAs (miRNAs) broadly regulate normal biological functions of bone and the progression of fracture healing and osteoporosis. Recently, it has been reported that miR-1224-5p in fracture plasma is a potential therapy for osteogenesis. To investigate the roles of miR-1224-5p and the Rap1 signaling pathway in fracture healing and osteoporosis development and progression, we used BMMs, BMSCs, and skull osteoblast precursor cells for in vitro osteogenesis and osteoclastogenesis studies. Osteoblastogenesis and osteoclastogenesis were detected by ALP, ARS, and TRAP staining and bone slice resorption pit assays. The miR-1224-5p target gene was assessed by siRNA-mediated target gene knockdown and luciferase reporter assays. To explore the Rap1 pathway, we performed high-throughput sequencing, western blotting, RT-PCR, chromatin immunoprecipitation assays and immunohistochemical staining. In vivo, bone healing was judged by the cortical femoral defect, cranial bone defect and femoral fracture models. Progression of osteoporosis was evaluated by an ovariectomy model and an aged osteoporosis model. We discovered that the expression of miR-1224-5p was positively correlated with fracture healing progression. Moreover, in vitro, overexpression of miR-1224-5p slowed Rankl-induced osteoclast differentiation and promoted osteoblast differentiation via the Rap1-signaling pathway by targeting ADCY2. In addition, in vivo overexpression of miR-1224-5p significantly promoted fracture healing and ameliorated the progression of osteoporosis caused by estrogen deficiency or aging. Furthermore, knockdown of miRNA-1224-5p inhibited bone regeneration in mice and accelerated the progression of osteoporosis in elderly mice. Taken together, these results identify miR-1224-5p as a key bone osteogenic regulator, which may be a potential therapeutic target for osteoporosis and fracture nonunion.

Low power resistive random access memory using interfaceengineered dielectric stack of SiOx/a-Si/TiOy with 1D1R-like structure

Chun-Hu Cheng,K.I. Chou,Zhi-Wei Zheng,Hsiao-Hsuan Hsu 한국물리학회 2014 Current Applied Physics Vol.14 No.1

In this study, we report a resistive random access memory (RRAM) using trilayer SiOx/a-Si/TiOy film structure. The low switching energy of <10 pJ, highly uniform current distribution (<13% variation), fast 50-ns speed and stable cycling endurance for 106 cycles are simultaneously achieved in this RRAM device. Such good performance can be ascribed to the use of interface-engineered dielectric stack with 1D1R-like structure. The SiOx tunnel barrier in contact with top Ni electrode to form diode-like rectifying element not only lowers self-compliance switching currents, but also improves cycling endurance, which is favorable for the application of high-density 3D memory.