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Waste engine oil (WEO) and waste polyethylene (WPE) are two common wastes, which are easy to pollute the environment. As the primary material in road construction, natural asphalt is a non-renewable energy source and asphalt is vulnerable to ultraviolet (UV) radiation during the service life. It results in degradation of asphalt pavement performance. In this paper, 22 wt % to 82 wt % of WEO and WPE were used to modify asphalts and the UV aging simulation experiment was carried out. The physical parameters of asphalts before the UV aging experiment show that the asphalt containing 42 wt % WPE and 62 wt % WEO mixture (42 wt % WPE + 62 wt % WEO) has similar physical properties with that of the matrix asphalt. Besides, gel permeation chromatography (GPC) verifies that the molecular weight distribution of the asphalt containing 42 wt % WPE + 62 wt % WEO is close to that of the matrix asphalt. The storage stability test shows that 42 wt % WPE + 62 wt % WEO has good compatibility with the matrix asphalt. The functional groups and micro-morphology of asphalts before and after the UV aging experiment were investigated by Fourier transform infrared spectroscopy (FTIR) and atomic force microscopy (AFM). FTIR results display that 42 wt % WPE + 62 wt % WEO can effectively reduce the formation of carbonyl and sulfoxide functional groups. AFM shows that 42 wt % WPE + 62 wt % WEO can also retard the formation of a &ldquo, bee-like&rdquo, structure in asphalt after the UV aging experiment. Based on the above results, it can be concluded that WEO and WPE mixture can replace part of asphalt and improve the UV aging resistance of asphalt.

Currently the investigation on recycled cement concrete aggregate has been widely conducted, while the understanding of the recycled polymer concrete aggregate is still limited. This study aims to fill this knowledge gap through the experimental investigation on mechanical and durability performance. Specifically, the remolded polyurethane stabilized Pisha sandstone was collected as the recycled polymer concrete aggregate. The remolded Pisha sandstone was then applied to re-prepare the polyurethane-based composites. After that, the mechanical performance of the prepared composites was first examined with unconfined and triaxial compressive tests. The results indicated that the Pisha sandstone reduces the composite&rsquo, s compressive strength. The reduction is caused by the remained polyurethane material on the surface of the remolded aggregate, which reduces its bond strength with the new polyurethane material. Aiming at this issue, this study applied the ethylene-vinyl acetate (EVA) to enhance the bond performance between the polyurethane and remolded sandstone. The test results indicated both the unconfined and triaxle compressive strength of the polyurethane composites were enhanced with the added EVA content. Furthermore, the durability performance of the EVA-modified composites were examined through freeze-thaw and wet-dry cycle tests. The test results indicated the EVA could enhance the polyurethane composites&rsquo, resistance to both wet-dry and freeze-thaw cycles. Overall, the modification with EVA can compensate for the strength loss of polyurethane composites because of the applied remolded aggregate and enhance its sustainability.

An efficient C-H/N-H functionalization with allenes was enabled via versatile electro-oxidative cobalt catalysis. Thus, electrochemical C-H activations were accomplished with high levels of chemoselectivity and regioselectivity in an operationally simple undivided cell setup. The user-friendly nature of this protocol was highlighted by excellent functional group tolerance, an electro-reductive removable hydrazide directing group and easy scalability. Experimental mechanistic studies were indicative of a facile BIES C-H cobaltation event.

Recent studies have demonstrated the implication of long noncoding RNAs (lncRNAs) in a variety of physiological and pathological processes. However, the majority of lncRNAs are functionally unknown. The current study describes that the lncRNA MALAT1 regulates TGF-β/Smad signaling pathway through formation of a lncRNA-protein complex containing Smads, SETD2 and PPM1A. Our data show that this lncRNA-proteins complex facilitates the dephosphorylation of pSmad2/3 by providing the interaction niche for pSmad2/3 and their specific phosphatase PPM1A, thus terminating TGF-β/Smad signaling in hepatic cells. Based on these mechanistic studies, we performed further experiments to determine whether depletion of MALAT1 would augment cellular TGF-β/Smad signaling. We observed that MALAT1 depletion enhanced TGF-β/Smad signaling response, as reflect by amplification of Smad-mediated differentiation of induced pluripotent stem (iPS) cells to hepatocytes. Our experimental results demonstrate an important role of MALAT1 for regulation of TGF-β/Smad signaling in hepatic cells. Given the diverse functions of TGF-β/Smad pathway in various physiological and pathogenic processes, our results described in the current study will have broad implications for further understanding the role of MALAT1 in TGF-β/Smad pathway in human biology and disease.

We demonstrate a sub-picosecond resolution time-offset comparison over 100 km long fiber between using asynchronized dual-comb linear optical sampling and the time interval counter.

We report the dark matter search results obtained using the full 132 ton$\cdot$day exposure of the PandaX-II experiment, including all data from March 2016 to August 2018. No significant excess of events is identified above the expected background. Upper limits are set on the spin-independent dark matter-nucleon interactions. The lowest 90% confidence level exclusion on the spin-independent cross section is $2.2\times 10^{-46}$ cm$^2$ at a WIMP mass of 30 GeV/$c^2$., Comment: 23 pages, 19 figures, 6 tables, version published in Chinese Physics C

Newly public firms may provide misleading information about their business plans in their initial public offering (IPO) prospectuses. Using textual analysis, we develop a simple measure of such misleading information based on the difference between the emphasis placed on business lines in the main textual description and the corresponding information from the accounting tables. We examine our measure of misleading information using a sample of 1878 IPOs in China from 2010 to 2019. We find that the degree of misleading information is greater when firms find it more difficult to get regulatory approval for an IPO. Furthermore, the amount of misleading information is greater for firms with higher leverage and more segmented businesses. We also find some evidence that the stock returns of firms which present a greater amount of misleading information are lower.

The traction capacity of the mining machine is greatly influenced by the traction rheological properties of the deep-sea sediments. The best simulative soil was prepared for substituting the deep-sea sediment based on the deep-sea sediment collected from the Pacific C-C mining area. Traction rheological properties of the simulative soil were studied by a home-made test apparatus. In order to accurately describe the traction rheological properties and determine traction rheological parameters, the Newtonian dashpot in Maxwell body of Burgers model was replaced by a self-similarity spring-dashpot fractance and a new rheological constitutive model was deduced by fractional derivative theory. The results show the simulative soil has obvious non-attenuate rheological properties. The transient creep and stable creep rate increase with the traction, but they decrease with ground pressure. The fractional derivative Burgers model are better in describing non-attenuate rheological properties of the simulative soil than the classical Burgers model. For the new traction rheological constitutive equation of the simulative soil, the traction rheological parameters can be obtained by fitting the tested traction creep data with the traction creep constitutive equation. The ground contact length of track and walking velocity of the mining machine predicted by the traction rheological constitutive equation can be used to take full advantages of the maximum traction provided by the soil and safely improve mining efficiency.

In this paper, we propose an edge detector based on feature re-extraction (FRE) of a deep convolutional neural network to effectively utilize features extracted from each stage, and design a new loss function. The proposed detector is mainly composed of three modules: backbone, side-output, and feature fusion. The backbone module provides preliminary feature extraction; the side-output module makes network architecture more robustly map features from different stages of the backbone network to edge-pixel space by applying residual learning, and the feature fusion module generates the edge map. Generalization ability on the same distribution is verified using the BSDS500 dataset, achieving optimal dataset scale (ODS) F-score = 0.804. Cross-distribution generalization ability is verified on the NYUDv2 dataset, achieving ODS F-score = 0.701. In addition, we find that freezing backbone network can significantly speed up training process, without much overall accuracy loss (ODS F-score of 0.791 after 5.4k iterations).

Multi-layered media is the most common structure in artificial and natural surroundings, and it is considered as a good candidate for mathematical model. The anisotropic properties and viscoelastic properties of layer materials have been widely used in multi-layered medium. Furthermore, the interlayer condition between the layers also plays an important role in the mechanical behavior of multi-layered medium. Despite many numerical approaches having been applied in these analyses, only few analytical solution were developed to analyze the effects of these three issues at the same time. The objective of this study is to develop an analytical solution that can be used for analyzing the impact of interlayer conditions on the mechanical behavior of anisotropic multi-layered medium overlaying viscoelastic layer subjected to axisymmetric loading, but the anisotropy property was approximated as transversely isotropy. The interlayer condition between the adjacent layers will also be considered. Details of the mathematical derivation, implementation and verification of the proposed analytical solution were presented. Subsequent numerical results demonstrate that both viscoelastic, transverse isotropy and interlayer condition could substantially contribute to the mechanical behavior of the multi-layered medium.

Temperature sensing is an important adaptive mechanism for warm-blooded animals such as humans. ThermoTRP ion channels are activated by distinct but overlapping physiological temperatures. Our previous research demonstrated that sorting nexin 11 (SNX11) regulates lysosomal degradation of plasma membrane TRPV3, one of ThermoTRP ion channel proteins. Here, we found that SNX11, a vesicular trafficking protein, modulates mouse behaviour in response to temperature changes. Snx11-knockout mice exhibit a stronger preference for mild temperatures along with enhanced sensitivity to harmful heat. Mechanistically, keratinocytes from Snx11-knockout mice exhibit a larger temperature-gated TRPV3 membrane current and have enhanced thermoTRPV3 expression in the plasma membrane compared to wild-type keratinocytes. Additionally, Snx11-knockout mice show higher endogenous TRPV3 protein levels in skin tissues than wild-type mice do. Therefore, our results indicate that SNX11 may regulate thermal perception via alteration of functional thermoTRPV3 on the plasma membrane of thermally sensitive cells, which is the first link between vesicular trafficking and thermal transduction.

Unmanned aerial vehicle (UAV) is a power-driven aircraft that is unmanned and reusable. The purpose of this study is to accurately estimate the state of charge (SOC) of lithium-ion batteries for UAVs. A support vector machine (SVM) method, SVM is a type of learning machine based on statistical learning, is used as the input variable of the battery charging discharge data (current, voltage and temperature). The kernel of the radial basis function is the best kernel of authors’ experiment, where the C, [inline-formula] and g values are 1, 0.012 and 0.0125, respectively. The experimental results from the lithium-ion battery data at NASA Ames Prognostics Center of Excellence demonstrate the potential application of the proposed method as an effective tool for battery SOC prediction. The accuracy of the whole experiment is 98.42%. Mean-squared error is 1.783%. The experimental results show that the model has higher accuracy in predicting the discharge capacity of lithium battery SOC-training samples.

Background: Tumor-induced immunosuppression can impede tumor-specific immune responses and limit the effects of cancer immunotherapy. The aim of this study was to investigate the possible effects of sequential chemoimmunotherapeutic strategies to enhance antitumor immune responses. Methods: Using the E7-expressing tumor TC-1 as the tumor model, the treatment groups were divided into the following groups: (1) inactivated allogeneic leukocyte infusion (ALI), (2) ALI + MMC-inactivated TC-1 cell vaccine, and (3) ALI + MMC-inactivated TC-1 cell vaccine + cyclophosphamide (CTX). Results: In our study, we demonstrated that treatment with immune-modulating doses of CTX results in a beneficial tumor microenvironment with the suppression of Tregs. ALI has a limited therapeutic effect, as does the MMC-inactivated TC-1 cell vaccine. Our results showed that CTX preconditioning and persistent ALI treatment along with the MMC-inactivated TC-1 cell vaccine resulted in significant inhibition of tumor growth and extended survival. Conclusion: Our study illustrated the effects of immune-modulating doses of a sequential chemoimmunotherapeutic strategy targeting the tumor and its microenvironment. The results suggest potential clinical effects for the immunotherapy of HPV-associated malignancies. Keywords: Alloantigen, Cyclophosphamide, Immunotherapy, Regulatory T cells, Tumor microenvironment

In deep-sea mining engineering, the compression–shear coupling effect of the sediment on the moving tracked mining vehicle must be considered, since it is proved to be existing in compression–shear...

The 450 and 600 °C isothermal section of the Zn-Al-Ni-Sb quaternary system with Zn being fixed at 93 at.% have been studied experimentally by using x-ray diffraction and scanning electron microscopy coupled with energy dispersive spectroscopy. The solubility of Al in the γ phase is no more than 2.6 and 1.5 at.% at 450 and 600 °C, respectively. As the temperature rises from 450 to 600 °C, the solubility of Zn in the AlSb phase increases from 3.0 to 10.3 at.%. Two four-phase regions and one four-phase region have been confirmed experimentally at 450 and 600 °C. No new ternary and quaternary compounds were found in the study.

DNA vaccination is an effective way to induce specific immunity. In our study, we used magnetosomes (bacterial magnetic particles, BMPs) as the vehicle of a DNA complex of a secondary lymphoid tissue chemokine, human papillomavirus type E7 (HPV-E7) and Ig-Fc fragment (pSLC-E7-Fc) to produce a gene vaccine (BMP-V) for tumor immunotherapy. In a mouse tumour model, intramuscular injection of BMP-V plus magnetic exposure induced E7- specific immunity eliciting to tumor inhibition. Taken together, these results demonstrated that BMP could be applied as a DNA vehicle to induce specific immune effect.

Mixed allogeneic lymphocyte response has activated considering T lymphocytes and elicit type 1 cytokines which induced antitumor immunity. Using TC-1 cancer model, we demonstrated the response of inactivated allogeneic leukocytes infusion (ALI) to generate antitumor immune response. In TC-1 tumor model, ALI induced a delayed cancer development and a prolonged survival. Our study illustrated that ALI might elicit strong antitumor immune response. The method strategy would be easy and efficient strategy in tumor immunotherapy.

This paper presents a novel 5-tube hollow-core anti-resonant fiber (HC-ARF) that is added a flat glass bar between the nested tubes of hollow-core nested anti-resonant nodeless fiber (1-bar NANF). It realizes the ultra-low loss, wide bandwidth and single-mode transmission by adjusting cladding tube parameters. The confinement loss of 5-tube 1-bar NANF is less than 0.05 dB/km in the range of 1.2–1.7 μ m. And the loss ratio between the minimum high-order mode loss and fundamental mode loss can reach 28000. In addition, the 1-bar NANF is compared with the other optical fibers where anti-resonance tube is consists of three glass layers. The simulation result shows that the performance of the 1-bar NANF is insensitive to the curvature of the second glass layer under specified conditions. The bending performances and the fabrication feasibility of 1-bar NANF are also discussed.

The patterns of thematic progression, greatly influenced by culture-peculiar thinking patterns and language-particular features, reflect the integration of form and meaning in the flow of information in discourse. The economic discourse has its distinct linguistic characteristics and important communicative purposes. Thus, related research on the thematic progression of economic discourse is important for us to understand the language use in the context of economic and financial activities and also has important implications for language learning and teaching, translation, automated language information processing etc. This study first employs CiteSpace, a document visualization tool, to review the existing related studies on the economic discourse in China, and then analyzes the major patterns of thematic progression in the economic discourse based on the English and Chinese reports from The Economist. Through our discussion, we aim to explore universals and peculiarities of thematic progression in English-Chinese economic discourse and discuss the reasons attributing to major distinctions between the two languages in terms of thematic progression.

Ruthenium-catalyzed C−H chalcogenations of anilides with readily available diselenides and disulfides have been achieved. Our strategy features ample substrate scope, affording the mono-ortho selenylated and thiolated anilides with complete site selectivity control and high catalytic efficacy. Detailed mechanistic studies provide strong support for a facile base-assisted internal electrophilic substitution (BIES) metalation event.

Applying waste tire rubber powder to modify the asphalt binder is a promising protocol to achieve sustainable pavement materials. This study aims to examine the feasibility of using Lucobit type asphalt additive in the rubberized asphalt and further enhance its performance. The 90# asphalt binder and the rubber powder with 30 mesh were selected to prepare the rubberized asphalt. Two Lucobit adding ratios (5% and 10%) were then selected for the modification of three types rubberized base binder (Rubber replacement ratios 15%, 20%, and 25%). The modified asphalt binder was prepared under 180 ± 5 ℃ by using the high-speed shear mixer under 5000 rpm for 2 h. Then the FTIR and TGA tests were conducted for the phase analysis of the asphalt co-modified with rubber powder and Lucobit. The test results indicated the modification mainly belong to the physical blending instead of chemical bonding. Further study with DSR test indicated the added Lucobit can further enhance the high-temperature stability of the rubberized asphalt. Further study based on Multiple Stress Creep Recovery (MSCR) test indicated the anti-rutting performance of the asphalt binder would be enhanced while the sensibility of asphalt binder to shear stress would be reduced with the added Lucobit. Finally, the topography analysis on the original and aged binders were analyzed with Atomic Force Microscopy (AFM) test. The results indicated obviously reduced bee-like structure can be observed in the samples with Lucobit, which is in accordance with the measured complex modulus after aging tests. Overall, this study indicates the added Lucobit can further enhance the high-temperature stability, antiaging performance, and reduce shear stress sensitivity of the asphalt binder.

In this paper, double-layered hole transport material (HTM) was designed and fabricated by adding a thin CuInS2 film between perovskite and Spiro-OMeTAD (Spiro) layers. The power conversion efficiency (PCE) of the perovskite solar cells (PSCs) with double-layered HTM of CuInS2/Spiro was improved to 19.63% from 17.97% for the devices with pure Spiro. Moreover, the operational stability of the PSCs with double-layered HTM of CuInS2/Spiro was enhanced. The PCE of the PSCs with CuInS2/Spiro retains 91% of the initial value after 30 days storage in ambient atmosphere. The experimental results indicate that the improved performance could be come from the energy band match between CuInS2 and Spiro, fast hole extraction and transport, and decreased charge recombination in the PSCs with double-layered HTM of CuInS2/Spiro. This work provides a promising prospect to design a low-cost and high stability HTM for commercial PSCs.

The 'zigzag' model formulates some of the fundamental principles underpinning the dynamic interactions between pathogen effectors and plant immunity. As key virulence factors, effectors often exhibit a pattern of rapid evolution, presumably as a result of the host-pathogen arms race. Here, we summarize the current knowledge of mechanisms that may accelerate effector evolution in the highly successful Phytophthora pathogens. Recent findings on epigenetic regulation of effector genes that allows evasion of host recognition and maintenance of cost/benefit balance, and a conserved structural unit in effector proteins that may promote the evolution of virulence activities are highlighted.

An online cryogenic distillation system for the removal of krypton and radon from xenon was designed and constructed for PandaX-4T, a highly sensitive dark matter detection experiment. The krypton content in a commercial xenon product is expected to be reduced by 7 orders of magnitude with 99% xenon collection efficiency at a flow rate of 10 kg/h by design. The same system can reduce radon content in xenon by reversed operation, with an expected radon reduction factor of about 1.8 in PandaX-4T under a flow rate of 56.5 kg/h. The commissioning of this system was completed, with krypton and radon operations tested under respective working conditions. The krypton concentration of the product xenon was measured with an upper limit of 8.0 ppt., Comment: 18 pages, 12 figures

All‐inorganic perovskite quantum dots (QDs) CsPbX3 (X = Cl, Br, and I) have recently emerged as a new promising class of X‐ray scintillators. However, the instability of perovskite QDs and the strong optical scattering of the thick opaque QD scintillator film imped it to realize high‐quality and robust X‐ray image. Herein, the europium (Eu) doped CsPbBr3 QDs are in situ grown inside transparent amorphous matrix to form glass‐ceramic (GC) scintillator with glass phase serving as both matrix and encapsulation for the perovskite QD scintillators. The small amount of Eu dopant optimizes the crystallization of CsPbBr3 QDs and makes their distribution more uniform in the glass matrix, which can significantly reduce the light scattering and also enhance the photoluminescence emission of CsPbBr3 QDs. As a result, a remarkably high spatial resolution of 15.0 lp mm−1 is realized thanks to the reduced light scattering, which is so far a record resolution for perovskite scintillator based X‐ray imaging, and the scintillation stability is also significantly improved compared to the bare perovskite QD scintillators. Those results provide an effective platform particularly for the emerging perovskite nanocrystal scintillators to reduce light scattering and improve radiation hardness., Europium (Eu) doped perovskite QD glass ceramic works as perfect scintillator because of high light yield, superior transparency, and hence significantly suppressed optical crosstalk, as well as the protection of glass matrix. Eventually the record‐high imaging resolution of 15.0 lp mm−1 is achieved, the radiation hardness is also significantly improved.

The sinkage of a moving tracked mining vehicle is greatly affected by the combined compression-shear rheological properties of soft deep-sea sediments. For test purposes, the best sediment simulant is prepared based on soft deep-sea sediment from a C-C poly-metallic nodule mining area in the Pacific Ocean. Compressive creep tests and shear creep tests are combined to obtain compressive and shear rheological parameters to establish a combined compressive-shear rheological constitutive model and a compression-sinkage rheological constitutive model. The combined compression-shear rheological sinkage of the tracked mining vehicle at different speeds is calculated using the RecurDyn software with a selfprogrammed subroutine to implement the combined compression-shear rheological constitutive model. The model results are compared with shear rheological sinkage and ordinary sinkage (without consideration of rheological properties). These results show that the combined compression-shear rheological constitutive model must be taken into account when calculating the sinkage of a tracked mining vehicle. The combined compression-shear rheological sinkage decrease with vehicle speed and is the largest among the three types of sinkage. The developed subroutine in the RecurDyn software can be used to study the performance and structural optimization of moving tracked mining vehicles.

An efficient cobalt(III)-catalyzed C-2-selective indole C–H hydroarylation of acrolein, enones, and glyoxylates was achieved under mild reaction conditions. The versatile cobalt(III) catalyst displayed excellent positional selectivity with the assistance of pyrimidinyl, pyridyl, and pyrazolyl directing groups, thus overcoming the inherent C-3 selectivity of an electrophilic indole derivatization. This approach provides an expedient route to indolyl-substituted aldehydes, ketones, and esters with wide functional group tolerance. In addition, it also features high step- and atom-economy.

Ruthenium- and silver-catalyzed selective C–H alkenylations, thiolations and selenylations of phenazone (antipyrine) – a non-steroidal anti-inflammatory drug – have been developed. This method features ample substrate scope, affording typically the mono-ortho alkenylated, thiolated and selenylated products in good yields with complete site selectivity control. This strategy offers an efficient protocol for the modification of antipyrine derivatives.

The transition metal-catalyzed transformation of otherwise inert C–H bonds into substituted alkenes offers a versatile tool for the synthesis of value added olefinic molecules. Recent developments in the directing group assisted C–H activation approach ensured high levels of positional selectivity. A vast number of coordinating groups have been utilized in directed C–H alkenylation, which are often not removable after the desired transformation. However, the concept of easily removable or traceless directing group strategy overcomes this limitation and enables site-selective C–H alkenylation of relevance to academia and the practitioners in industry. Various easily removable or transformable directing groups utilized in the transition metal-catalyzed oxidative C–H alkenylations are discussed in this review until February 2017.

Halide perovskite (HP) nanocrystals (NCs) have recently shown great potential for X-ray detection and imaging. However, the practical application still has a long way to go with many technical requirements waiting to be fulfilled, including structure optimization, stability enhancement, and cost reduction. A design principle in this beginning stage is urgently needed but still lacking. Herein, with an "emitter-in-matrix" principle refined from commercial scintillators, CsPbBr

An efficient electro-oxidative C-H/N-H activation with 1,3-diynes has been achieved with a robust earth-abundant cobalt catalyst. The electrochemical C-H functionalization was accomplished with ample scope and remarkable functional group compatibility in a simple undivided cell. This protocol avoids the utilization of stoichiometric and cost-intensive chemical oxidants in C-H activation, thus forming hydrogen as the only byproduct.

Citrus greening, or Huanglongbing (HLB), is currently the most devasting disease of citrus, creating unprecedented crisis for the multibillion-dollar global citrus industry. To-date, there is no effective cure and disease management relies on early detection and removal of infected trees. Thus, it is imperative that accurate, timely, and robust disease detection and diagnosis technologies are available to minimize the spread of disease. This study reports a sensitive and selective label-free biosensor that combines the physical and chemical advantages of carbon nanomaterials like single-walled carbon nanotubes (SWNTs) in a field-effect transistor (FET)/chemiresistor architecture with selective antibodies against Sec-delivered effector 1 (SDE1), a secreted protein biomarker, for the detection of HLB. The biosensor detected SDE1 biomarkers for citrus greening in plant tissue extracts with the dynamic range over three orders of magnitude in the low nanomolar to micromolar concentration range and limit of detection of 5 nM. The study also demonstrated the use of the standard additions assay method with the biosensor to attain a 90-percent signal recovery in concentrated plant tissue extract, allowing for quantitative detection without an external calibration. Adopting the novel detection strategy targeting the secreted protein biomarker, SDE1, addresses some of the challenges faced by current methods of nucleic acid-based assays and symptom-based diagnosis, which have been found prone to false negatives and misdiagnoses, respectively.

We report the Neutrino-less Double Beta Decay (NLDBD) search results from PandaX-II dual-phase liquid xenon time projection chamber. The total live time used in this analysis is 403.1 days from June 2016 to August 2018. With NLDBD-optimized event selection criteria, we obtain a fiducial mass of 219 kg of natural xenon. The accumulated xenon exposure is 242 kg$\cdot$yr, or equivalently 22.2 kg$\cdot$yr of $^{136}$Xe exposure. At the region around $^{136}$Xe decay Q-value of 2458 keV, the energy resolution of PandaX-II is 4.2%. We find no evidence of NLDBD in PandaX-II and establish a lower limit for decay half-life of 2.4 $ \times 10^{23} $ yr at the 90% confidence level, which corresponds to an effective Majorana neutrino mass $m_{\beta \beta} < (1.3 - 3.5)$ eV. This is the first NLDBD result reported from a dual-phase xenon experiment., Comment: Submitted to Chinese Physics C

RNA silencing is an essential gene-regulation mechanism in eukaryotic organisms. Guided by small RNAs (sRNAs) of 20–25 nt in length, RNA silencing broadly governs a wide range of biological processes. In addition to regulating endogenous gene expression and inhibiting viral infection, accumulating evidence suggests that sRNAs can also function as antimicrobial agents against nonviral pathogens and directly silence gene targets in invading pathogen cells. Here, we summarize current understanding of this host-induced gene silencing (HIGS) process as a defense mechanism during natural infection. Specific focuses will be on recent advancement in the sRNA executors of HIGS and their potential delivery mechanisms from the plant host to filamentous eukaryotic pathogens, including fungi and Phytophthora species. Implications of these new findings in the applications of HIGS as a tool for engineering disease resistance is discussed.

Phytophthora are eukaryotic pathogens that cause enormous losses in agriculture and forestry. Each Phytophthora species encodes hundreds of effector proteins that collectively have essential roles in manipulating host cellular processes and facilitating disease development. Here we report the crystal structure of the effector Phytophthora suppressor of RNA silencing 2 (PSR2). PSR2 produced by the soybean pathogen Phytophthora sojae ( Ps PSR2) consists of seven tandem repeat units, including one W-Y motif and six L-W-Y motifs. Each L-W-Y motif forms a highly conserved fold consisting of five α-helices. Adjacent units are connected through stable, directional linkages between an internal loop at the C terminus of one unit and a hydrophobic pocket at the N terminus of the following unit. This unique concatenation results in an overall stick-like structure of Ps PSR2. Genome-wide analyses reveal 293 effectors from five Phytophthora species that have the Ps PSR2-like arrangement, that is, containing a W-Y motif as the “start” unit, various numbers of L-W-Y motifs as the “middle” units, and a degenerate L-W-Y as the “end” unit. Residues involved in the interunit interactions show significant conservation, suggesting that these effectors also use the conserved concatenation mechanism. Furthermore, functional analysis demonstrates differential contributions of individual units to the virulence activity of Ps PSR2. These findings suggest that the L-W-Y fold is a basic structural and functional module that may serve as a “building block” to accelerate effector evolution in Phytophthora .

Plant pathogens employ diverse secreted effector proteins to manipulate host physiology and defense in order to foster diseases. The destructive

Phytophthora pathogens manipulate host innate immunity by secreting numerous RxLR effectors, thereby facilitating pathogen colonization. Predicted single and tandem repeats of WY domains are the most prominent C-terminal motifs conserved across the Phytophthora RxLR superfamily. However, the functions of individual WY domains in effectors remain poorly understood. The Phytophthora sojae effector PSR1 promotes infection by suppressing small RNA biogenesis in plant hosts. We identified one single WY domain following the RxLR motif in PSR1. This domain was required for RNA silencing suppression activity and infection in Nicotiana benthamiana, Arabidopsis and soybean. Mutations of the conserved residues in the WY domain did not affect the subcellular localization of PSR1 but abolished its effect on plant development and resistance to viral and Phytophthora pathogens. This is at least in part due to decreased protein stability of the PSR1 mutants in planta. The identification of the WY domain in PSR1 allows predicts that a family of PSR1-like effectors also possess RNA silencing suppression activity. Mutation of the conserved residues in two members of this family, PpPSR1L from P. parasitica and PcPSR1L from P. capsici, perturbed their biological functions, indicating that the WY domain is critical in Phytophthora PSR1 and PSR1-like effectors.

Plants evolved an array of disease resistance genes (R genes) to fight pathogens. In the absence of pathogen infection, NBS-LRR genes, which comprise a major subfamily of R genes, are suppressed by a small RNA cascade involving microRNAs (miRNAs) that trigger the biogenesis of phased siRNAs (phasiRNAs) from R gene transcripts. However, whether or how R genes influence small RNA biogenesis is unknown. In this study, we isolate a mutant with global defects in the biogenesis of miRNAs and phasiRNAs in Arabidopsis thaliana and trace the defects to the over accumulation and nuclear localization of an R protein SNC1. We show that nuclear SNC1 represses the transcription of miRNA and phasiRNA loci, probably through the transcriptional corepressor TPR1. Intriguingly, nuclear SNC1 reduces the accumulation of phasiRNAs from three source R genes and concomitantly, the expression of a majority of the ~170R genes is up-regulated. Taken together, this study suggests an R gene-miRNA-phasiRNA regulatory module that amplifies plant immune responses., A small RNA-based signaling cascade prevents the induction of plant resistance genes (R-genes) in the absence of pathogen challenge. Here Cai et al. show that nuclear accumulation of the R protein SNC1 can activate immunity by suppressing small RNA production and releasing R-gene repression.

RNA silencing (RNAi) has a well-established role in anti-viral immunity in plants. The destructive eukaryotic pathogen Phytophthora encodes suppressors of RNAi (PSRs), which enhance plant susceptibility. However, the role of small RNAs in defense against eukaryotic pathogens is unclear. Here, we show that Phytophthora infection of Arabidopsis leads to increased production of a diverse pool of secondary small interfering RNAs (siRNAs). Instead of regulating endogenous plant genes, these siRNAs are found in extracellular vesicles and likely silence target genes in Phytophthora during natural infection. Introduction of a plant siRNA in Phytophthora leads to developmental deficiency and abolishes virulence, while Arabidopsis mutants defective in secondary siRNA biogenesis are hypersusceptible. Notably, Phytophthora effector PSR2 specifically inhibits secondary siRNA biogenesis in Arabidopsis and promotes infection. These findings uncover the role of siRNAs as antimicrobial agents against eukaryotic pathogens and highlight a defense/counter-defense arms race centered on trans-kingdom gene silencing between hosts and pathogens.

We report a search for new physics signals using the low energy electron recoil events in the complete data set from PandaX-II, in light of the recent event excess reported by XENON1T. The data correspond to a total exposure of 100.7 ton⋅day with liquid xenon. With robust estimates of the dominant background spectra, we perform sensitive searches on solar axions and neutrinos with enhanced magnetic moment. It is found that the axion-electron coupling g Ae < 4.6 × 10–12 for an axion mass less than 0.1 keV/c 2 and the neutrino magnetic moment μν < 4.9 × 10–11 μ B at 90 % confidence level. The observed excess from XENON1T is within our experimental constraints.

Small RNAs are central players of RNA silencing in eukaryotes. These short RNA molecules (20-25 nucleotides in length) repress target gene expression based on sequence complementarity. While small RNAs are well-known for their essential function in regulating growth and development, recent research has revealed that they also influence plant immunity. Extensive changes in small RNA accumulation have been observed during infection. This review focuses on specific small RNA changes that are involved in plant responses to filamentous eukaryotic pathogens including fungi and oomycetes. We describe how changes in small RNA accumulation influence plant immunity and summarize the cellular processes affected by these small RNAs. In particular, we discuss secondary small interfering RNAs that directly modulate the expression of defense-related genes.

Filamentous eukaryotic pathogens including fungi and oomycetes are major threats of plant health. During the co-evolutionary arms race with the hosts, these pathogens have evolved a large repertoire of secreted virulence proteins, called effectors, to facilitate colonization and infection. Many effectors are believed to directly manipulate targeted processes inside the host cells; and a fundamental function of the effectors is to dampen immunity. Recent evidence suggests that the destructive oomycete pathogens in the genus Phytophthora encode RNA silencing suppressors. These effectors play an important virulence role during infection, likely through their inhibitory effect on host small RNA-mediated defense.