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In this work, a graphene-based planar terahertz electromagnetically induced transparency-like (EIT-like) metamaterial, composed of two horizontally symmetric mono-layer graphene micro-ring resonators (MRR) and a vertical mono-layer graphene micro-strip resonator (MSR), has been proposed. The transparent window was observed in the y polarization direction. By changing the carrier mobility of the graphene, the transparent window could be opened and closed while the position of the EIT-like window remained unchanged. The physical mechanism of the EIT-like effect was explained by the distribution of the electric field on E z and the three-level $\Lambda $ -type system. The theoretical fitting results based on the Lorentz oscillator model and the S-parameter inversion method were consistent with the numerical simulation results. In addition, the performance of the metamaterial for detecting the refractive index of the surrounding medium was analyzed. Numerical simulation showed that when the FOM exceeded 8.0, the sensitivity was 1.6 THz/RIU. Finally, as the graphene carrier mobility increased, the group delay of the device increased. The delay time reached 1.49 ps, and the group index was as high as 400. The proposed design provides a feasible method for the development of optical switches, biochemical molecular detection, and slow light equipment.

We demonstrate a virtual pretreatment patient-specific QA (PSQA) procedure that is capable of quantifying dosimetric effect on patient anatomy for both intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT). A machine learning prediction model was developed to use linear accelerator parameters derived from the DICOM-RT plan to predict delivery discrepancies at treatment delivery (defined as the difference between trajectory log file and DICOM-RT) and was coupled with an independent Monte Carlo dose calculation algorithm for dosimetric analysis. Machine learning models for IMRT and VMAT were trained and validated using 120 IMRT and 206 VMAT fields of prior patients, with 80% assigned for iterative training and testing, and 20% for post-training validation. Various prediction models were trained and validated, with the final models selected for clinical implementation being a boosted tree and bagged tree for IMRT and VMAT, respectively. After validation, these models were then applied clinically to predict the machine parameters at treatment delivery for 7 IMRT plans from various sites (61 fields) and 10 VMAT multi-target intracranial radiosurgery plans (35 arcs) and compared to the dosimetric effect calculated directly from trajectory log files. Dose indices tracked for targets and organs at risk included dose received by 99%, 95%, and 1% of the volume, mean dose, percent of volume receiving 25%-100% of the prescription dose. The average coefficient of determination (r

The emergence of inorganic antimony (Sb)-based perovskite-inspired solar cells simultaneously overcomes the poor stability and toxicity of lead (Pb)-based perovskite solar cells. However, in addition to reducing the toxicity of the device itself, further reducing the toxicity in the preparation process is also a necessary condition for commercialization. Herein, different anti-solvents have been used to precisely regulate the nucleation process and improve the quality of the films. Among them, the film with green anisole as a novel anti-solvent shows a dense surface morphology with good crystallinity and presents better light absorption. As a reward, the power conversion efficiency (PCE) of the champion device can reach 2.07% with low-cost carbon electrodes, which is improved by 470% in comparison with 0.44% for the control device without anti-solvent, and it is one of the top values for inorganic antimony (Sb)-based perovskite-inspired solar cells. In addition, the device exhibits good thermal and air stability without humidity control. This work will provide a new way to prepare highly efficient lead-free antimony-based perovskite-inspired solar cells.

The subject of the study is the new course of the PRC information policy, which was launched by the Fifth generation of the PRC leaders after the 18th Congress of the Chinese Communist Party in 2012. As a result, after the 18th Congress of the CPC was started the implementation of the Strong cyberpower strategy, which implies not only ensuring cyber security in the country, but also the usage of network resources to develop the national economy. Chinas new information policy was caused by the sharply increased role of information and communication technologies in international processes and the shift in the focus of international relations to the Asia-Pacific region. The PRCs information policy is based on the most advanced technologies in the IT sphere and the cooperation with private companies on regulating external and internal information security. The relevance of the research topic is due to the increasing role of ICT in international processes. In this context, the most important are the positions of the leading countries of the world to regulate this area, as well as the mechanisms and tools used by them. The Peoples Republic of China is one of the leaders in the field of scientific and technical developments and actively uses its achievements to accomplish tasks in the field of domestic and foreign policy. In this regard, the purpose of the study is to analyze and compare the development strategies of the PRC information policy and the resources that are necessary for their implementation. The unique network landscape, which was formed under the influence of government policy on control over published content and the sharing of digital services market among the three largest information corporations (Baidu, Tencent and Alibaba), has become an essential part of the countrys information security system and requires detailed study. The purpose of the article is to identify the evolution of Chinas information policy development strategy and resources for its implementation. This article also discusses the threats to the information security of the Peoples Republic of China and analyzes the approaches to ensuring it. The results of the study are the conclusions that show the role and place of information policy in the PRC foreign policy, the structure of the information security system and strategic approaches to the regulation of international relations in cyberspace.

A terahertz constant frequency reconfigurable metasurface based on tunable electromagnetically induced transparency (EIT)-like property was designed, whose transparency window frequency did not vary with Fermi energy. This structure was composed of two single-layer graphene resonators, namely, left double big rings and right double small rings. An evident transparency window (EIT-like phenomenon) was caused by the near-field coupling between bright modes of the two resonators in the transmission spectrum, in which amplitude over 80% was acquired at 1.98 THz. By individually reconfiguring the Fermi energy of each resonator, the EIT-like effects, transparency window amplitude, modulation speed and group delay could be actively controlled while the frequency of EIT-like window remained constant. Significantly, the transparency window was fully modulated without changing the frequency, and the maximum modulation depth reached 78%. Furthermore, the modulation speed also increased because the total graphene areaAwas effectively reduced in the proposed structure. Compared with other metasurface structures, the modulation properties of the proposed structure showed higher performance while the EIT-like window frequency remained static. This research provides an alternative method for developing constant frequency reconfigurable modulation terahertz devices (such as optical switches and modulators), as well as a potential approach for miniaturization of terahertz devices.

To overcome the effect of analyte thickness and limitation of single wavelength sensing, we propose an ultra-sensitive stereo metamaterial biosensor with double resonance frequencies based on coupling electric resonance and magnetic resonance. The electromagnetic analysis demonstrates that the double resonance coupling, induced by the stereo double-layer structure, can significantly improve sensitive biosensing at the terahertz frequency. The results show that by changing the size of the structure, each resonance frequency can be independently tuned in the range of 0.5–1.8 THz and the maximum refractive index sensitivity is 930.4 GHz/RIU. These results have significant implications for the detection of samples with different frequency points. The proposed ultra-sensitive stereo metamaterial structure has excellent potential for application in biomolecule detection and differentiation.

Different types of ionic liquid-based nanofluids have been studied by the researchers since the last two decades. Most of the studies have focused on the effect of nanoparticles on the enhancement optical properties (absorption, transmittance, scattering, and extinction coefficient) of the corresponding ionic liquid-based nanofluids. However, optical properties of ionic liquid-based fluid have considerable contribution to absorbance in nanofluids. Therefore, it is necessary to study absorption properties of the different ionic liquid-based fluid of corresponding nanofluids to utilize ionic liquid-based nanofluids in solar thermal applications. The effect of the anion and cation radius in the ionic liquid on the enhancement absorption properties of the corresponding nanofluids is investigated. Through the measurement results, we find that as the cation radius or anion radius increases, the transmittances of the corresponding nanofluids decrease sharply, which is beneficial to enhance absorption properties of Fe3O4/ionic liquid nanofluids. At the same time, we also find that the large viscosity increase the stability of ionic liquid nanofluids, which can affect the absorption properties. Understanding the effect of ILs base fluid on enhancement absorption properties of the corresponding nanofluids will pave the road for improving the efficiency for direct absorption solar collectors.

Occurrence, spatiotemporal variation, sources, and ecological risks of 20 organophosphorus flame retardants (OPFRs) in water and sediments from Hangzhou Bay (HZB) and its adjacent East China Sea (ECS) were investigated in this study. The concentrations of OPFRs (∑OPFR) in water ranged from 0.51 ng/L to 885 ng/L, with chlorinated OPFRs having the highest value. For sediments, ∑OPFR ranged from 2.93 ng/g, dry weight (dw) to 37.8 ng/g, dw. The ∑OPFR in the water and sediments of HZB in summer was significantly (p 0.05) higher than that in autumn. Additionally, the pollution of OPFRs in HZB was higher than that in ECS, and the high-concentration areas appeared in the north and south banks of HZB and near the coast of ECS. Principal component analysis-multiple linear regression showed that the OPFRs in this region were mainly from industrial products (e.g., polyurethane foam/paint/coating/textiles/product processing). In terms of aquatic environments, ecological risks were in a low (∑RQs0.1) to moderate (0.1∑RQs1) level, with regard to median exposure levels, a moderate risk (0.1∑RQs1) was found in the sediments during autumn. This study can provide new insights into the OPFR pollution characteristic and ecological risk in a specific eco-environment.

RNA interference (RNAi) is an across-kingdom gene regulatory and defense mechanism. However, little is known about how organisms sense initial cues to mobilize RNAi. Here, we show that wounding to Nicotiana benthamiana cells during virus intrusion activates RNAi-related gene expression through calcium signaling. A rapid wound-induced elevation in calcium fluxes triggers calmodulin-dependent activation of calmodulin-binding transcription activator-3 (CAMTA3), which activates RNA-dependent RNA polymerase-6 and Bifunctional nuclease-2 (BN2) transcription. BN2 stabilizes mRNAs encoding key components of RNAi machinery, notably AGONAUTE1/2 and DICER-LIKE1, by degrading their cognate microRNAs. Consequently, multiple RNAi genes are primed for combating virus invasion. Calmodulin-, CAMTA3-, or BN2-knockdown/knockout plants show increased susceptibility to geminivirus, cucumovirus, and potyvirus. Notably, Geminivirus V2 protein can disrupt the calmodulin-CAMTA3 interaction to counteract RNAi defense. These findings link Ca2+ signaling to RNAi and reveal versatility of host antiviral defense and viral counter-defense.

Urban residents often use public transit to travel throughout the city yet find it difficult to learn about events in one's neighborhood. Transit rides can also be isolating and routine, despite seeing the same people regularly. As a result, there are opportunities to connect with others on the same route. While digital technologies such as community systems, social media, and public displays have been studied to understand how people engage with each other in their community, little is known about the challenges people face when searching for local information while commuting. Our research explores how one form of technology, location-based games (LBGs), supports urban commuters in digital placemaking. We present a prototype of an LBG, City Explorer, that allows riders to maintain an awareness of location-specific events and to support the sharing of community information. City Explorer is designed for public transit riders in a metropolitan city to collaborate with other riders, supporting community awareness, and facilitating discussions related to places on their transit route.

A surge of breast cancer in health issues has set new challenges to clinical routine. With the help of data and image processing, artificial intelligence is possible to assist or automate doctors in diagnosis. On the basis of Wisconsin Breast Cancer Diagnosis (WDBC) database, this paper concentrated on Support Vector Machine (SVM) classifier and Random Forest (RF) to evaluate the features extracted from the tumor nucleus. Then the conclusion was made that SVM classifier has better prediction effect, with 97% AUC and accuracy. And the worst of the perimeter and concave points are two most important features among all the 30 characters. Hence only a model with 2 features can realize the idea results when the efficiency rate is high and data collection is simple. The outcomes showed that the promising factors to be applied to clinical diagnosis so as to suggest possible results, help laymen interpret pathological examination results, enhance the work efficiency of medical staff and mitigate their pressure.

To improve the refractive index sensitivity of a localized surface plasmon resonance (LSPR) sensor, we employ a new interparticle hybridization plasmon coupled resonance in a semiconductor-metal (Cu

Nonalcoholic Fatty Liver Disease (NAFLD) is the most common chronic liver disease in the world, which is characterized by liver fat accumulation unrelated to excessive drinking. Indeed, it attracts growing attention and becomes a global health problem. Due to the complexity of the NAFLD pathogenic mechanism, no related drugs were approved by Food and Drug Administration (FDA) till now. However, it is encouraging that a series of candidate drugs have entered the clinical trial stage with expectation to treat NAFLD. In this review, we summarized the main pathways and pathogenic mechanisms of NAFLD, as well as introduced the main potential therapeutic targets and the corresponding compounds involved in metabolism, inflammation and fibrosis. Furthermore, we also discuss the progress of these compounds, such as drug design and optimization, the choice of pharmacological properties and druglikeness, and the analysis of structure-activity relationship. This review offers a medium on future drug design and development, to be beneficial to relevant studies.

In plants, RNA-directed DNA methylation (RdDM)-mediated transcriptional gene silencing (TGS) is a natural antiviral defense against geminiviruses. Several geminiviral proteins have been shown to target the enzymes related to the methyl cycle or histone modification; however, it remains largely unknown whether and by which mechanism geminiviruses directly inhibit RdDM-mediated TGS. In this study, we showed that Cotton leaf curl Multan virus (CLCuMuV) V2 directly interacts with Nicotiana benthamiana AGO4 (NbAGO4) and that the L76S mutation in V2 (V2(L76S)) abolishes such interaction. We further showed that V2, but not V2(L76S), can suppresses RdDM and TGS. Silencing of NbAGO4 inhibits TGS, reduces the viral methylation level, and enhances CLCuMuV DNA accumulation. In contrast, the V2(L76S) substitution mutant attenuates CLCuMuV infection and enhances the viral methylation level. These findings reveal that CLCuMuV V2 contributes to viral infection by interaction with NbAGO4 to suppress RdDM-mediated TGS in plants. IMPORTANCE In plants, the RNA-directed DNA methylation (RdDM) pathway is a natural antiviral defense mechanism against geminiviruses. However, how geminiviruses counter RdDM-mediated defense is largely unknown. Our findings reveal that Cotton leaf curl Multan virus V2 contributes to viral infection by interaction with NbAGO4 to suppress RNA-directed DNA methylation-mediated transcriptional gene silencing in plants. Our work provides the first evidence that a geminiviral protein is able to directly target core RdDM components to counter RdDM-mediated TGS antiviral defense in plants, which extends our current understanding of viral counters to host antiviral defense.

To improve the refractive index sensitivity of a localized surface plasmon resonance (LSPR) sensor, we employ a new interparticle hybridization plasmon coupled resonance in a semiconductor-metal (Cu2-xS@Au) core-shell nanoparticle dimer (SMCSND), where the refractive index sensitivity can be improved by the generation of a tunable dual-band absorption spectrum at visible and near-infrared wavelengths. Owing to two LSPRs in different wavelength regions supported by the metal shell and semiconductor core, for the first time, we theoretically demonstrate that the new interparticle hybridization plasmon coupled mechanism in semiconductor-metal core-shell nanoparticle dimer depends not only on interparticle separation gap, but also on the nanoparticle shell thickness t. Electromagnetic model analysis reveals that there are two plasmon modes (Mode A and Mode C) associated with the interparticle hybridization plasmon coupled resonance, where the Mode C shows high sensitivity and figure of merit (FoM) to changes in the background dielectric medium. The tunability of the induced interparticle hybridization plasmon coupled resonance with different the separation distance and shell thickness can change the sensitivity and FoM of LSPR sensor in the visible to near-infrared region, which has broad application prospects.

Various nanoparticles have been developed for tumor-targeted drug delivery. However, nanoparticles with effective targeting and intelligent release capacity are still deficient. Herein, we present new pH-responsive and neutral charged nanoparticles for tumor-targeted anticancer drug delivery. Oxidized starch was synthesized and simultaneously modified by cholesterol and imidazole to obtain amphiphilic cholesterol/imidazole modified oxidized-starch (Cho-Imi-OS). Cho-Imi-OS easily self-assembled into nanoparticles by dialysis. Curcumin was selected as model drug to be encapsulated into the hydrophobic core of nanoparticles. The results showed that curcumin would effectively accumulate in cancer cells by encapsulating into the nanoparticles owing to the nano-sized structure and near neutral charged property of nanoparticles. Curcumin was released faster at pH 5.5 than that at pH 7.4 from the curcumin-loaded nanoparticles (Cur-NPs), indicating the pH-triggered release capacity of Cur-NPs after endocytosis by endosomes since the pH is low to 5.0∼6.0 in endosomes. Naturally, Cur-NPs showed significantly strong inhibitory effect on cancer cells.

Exploratory visual analysis is an iterative process, where analysts often start from an overview of the data. Subsequently, they often pursue different hypotheses through multiple rounds of interaction and analysis. Commercial visualization packages support mostly a model with a single analysis path, where the system view represents only the final state of the users' current analysis. In this paper, we investigate the benefit of using multiple workspaces to support alternative analyses, enabling users to create different workspaces to pursue multiple analysis paths at the same time. We implemented a prototype for multiple workspaces using a multi-tab design in a visual analytics system. The results of our user studies show that multiple workspaces: enable analysts to work on concurrent tasks, work well for organizing an analysis, and make it easy to revisit previous parts of their work.

Many people use public transit on a recurring basis to travel for work, school, or other activities. Yet rides can be isolating despite encountering the same people on a regular basis. We designed City Explorer, a city exploration transit game, to provide transit riders with a channel to strengthen the sense of community. In City Explorer, players collect points as they ride public transit. They can complete route-specific challenges and collaborate with other riders to multiply points by riding the same route. Players can also create geo-tagged posts to describe and share community-related information. We share our design requirements, followed by details of game features, and our implementation of City Explorer.

Orthogonal Frequency Division Multiplexing (OFDM) has recently been proposed as a modulation technique. For optical networks, because of its good spectral efficiency, flexibility, and tolerance to impairments, optical OFDM is much more flexible compared to traditional WDM systems, enabling elastic bandwidth transmissions, and optical networking is the future trend of development. In OFDM-based optical network the research of blocking rate has very important significance for network assessment. Current research for WDM network is basically based on a fixed bandwidth, in order to accommodate the future business and the fast-changing development of optical network, our study is based on variable bandwidth OFDM-based optical networks. We apply the mathematical analysis and theoretical derivation, based on the existing theory and algorithms, research blocking probability of the variable bandwidth of optical network, and then we will build a model for blocking probability.

Flexible bandwidth networking has recently been proposed as a spectrally efficient networking technology that effectively supports dynamically varying traffic demands [1]. This networking technology provides an opportunity to maximize spectral efficiency for each of many arbitrary bandwidth channels generated using one of many possible modulation formats [2]. Path Computation Element (PCE) is first introduced for dynamic routing and spectrum assignment problem in elastic optical network. We proposed three centralized and distributed routing and spectrum assignment solutions. They are Centralized Routing and Distributed Spectrum Assignment (CR+DSA), Centralized Routing and Centralized Spectrum Assignment (CR+CSA) and Distributed Routing and Distributed Spectrum Assignment (DR+DSA). The two centralized proposals both own PCE in its architecture. The performance of three proposed centralized and distributed routing and spectrum assignment solutions have been analyzed and compared. For the experimental evaluation, the performance of Centralized Routing and Centralized Spectrum Assignment is the most adaptable RSA strategy for the whole bandwidth-variable optical networks with dynamic traffic.