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Renewable resources are starting to constitute a growing portion of the total generation mix of the power system. A key difference between renewables and traditional generators is that many renewable resources are managed by individuals, especially in the distribution system. In this paper, we study the capacity investment and pricing problem, where multiple renewable producers compete in a decentralized market. It is known that most deterministic capacity games tend to result in very inefficient equilibria, even when there are a large number of similar players. In contrast, we show that due to the inherent randomness of renewable resources, the equilibria in our capacity game becomes efficient as the number of players grows and coincides with the centralized decision from the social planner's problem. This result provides a new perspective on how to look at the positive influence of randomness in a game framework as well as its contribution to resource planning, scheduling, and bidding. We validate our results by simulation studies using real world data., Appears in IEEE Transactions on Sustainable Computing

Black phosphorus (BP) is one of the most promising visible-near-infrared light-driven photocatalysts with favorite photoelectric properties and unique tunable direct band gap. Nevertheless, the further development of BP is hindered by the fast carrier recombination rate and high Gibbs free energy. Herein, an innovative strategy is developed for the controllable construction of Zn-P bonds induced zinc ferrite/black phosphorus (ZnFe2O4-BP) three dimensions (3D) microcavity structure. The Zn-P bonds serve as an efficient channel to optimize the carrier transport and Gibbs free energy of BP simultaneously. Besides, the unique 3D core-shell microcavity structure maintains the multiple reflections of sunlight inside the catalysts, which greatly improves the sunlight utilization upon photocatalysis. An optimized photocatalytic hydrogen production rate of 560 µmol h-1g-1 under near-infrared light (>820 nm) is achieved. A possible photocatalytic mechanism is proposed based on a series of experimental characterizations and theoretical calculations, this work provides a new sight to design high-quantity BP-based full-spectrum photocatalysts for solar energy conversion.

Background Recent studies have demonstrated that multidrug resistance (MDR) is a critical factor in the low efficacy of cancer chemotherapy. The main mechanism of MDR arises from the overexpression of P-glycoprotein (P-gp), which actively enhances drug efflux and limits the effectiveness of chemotherapeutic agents. Results In this study, we fabricated a “combo” nanoagent equipping with triple synergistic strategies for enhancing antitumor efficacy against MDR cells. Tumor homing-penetrating peptide endows the nanosystem with targeting and penetrating capabilities in the first stage of tumor internalization. The abundant amine groups of polyethylenimine (PEI)-modified nanoparticles then trigger a proton sponge effect to promote endo/lysosomal escape, which enhances the intracellular accumulation and retention of anticancer drugs. Furthermore, copper tetrakis(4-carboxyphenyl)porphyrin (CuTCPP) encapsulated in the nanosystem, effectively scavenges endogenous glutathione (GSH) to reduce the detoxification mediated by GSH and sensitize the cancer cells to drugs, while simultaneously serving as a photoacoustic imaging (PAI) contrast agent for image visualization. Moreover, we also verify that these versatile nanoparticles in combination with PD-1/PD-L1 blockade therapy can not only activate immunological responses but also inhibit P-gp expression to obliterate primary and metastatic tumors. Conclusion This work shows a significant enhancement in therapeutic efficacy against MDR cells and syngeneic tumors by using multiple MDR reversing strategies compared to an equivalent dose of free paclitaxel. Graphic Abstract

We report the detection of quasi-periodic oscillations (QPOs) in the radio light curves at 4.8, 8, and 14.5 GHz of the blazar OT 081, by means of the Weighted Wavelet Z-transform (WWZ) and Lomb–Scargle periodogram (LSP) methods. The LSP diagrams and time-averaged WWZ powers demonstrate several significant claims of QPOs above the 4σ confidence level: QPOs of ∼850 and ∼1500 d in the 4.8-GHz light curve, ∼850, ∼1120, and ∼1540 d in the 8-GHz light curve, ∼850 and ∼1130 d in the 14.5-GHz light curve. The Keplerian orbit parameters in a binary black hole system have been estimated, assuming the QPO of ∼850 d appearing in all three wavebands is a real periodicity. Moreover, a pure geometrical scenario with blobs moving helically inside the jet provides another plausible explanation for the detected QPOs.

Accurate and rapid quantitative detection of pesticide and pollutant levels in the actual sample can aid in protecting food security, environmental security, and human health. A high Raman enhancement factor and good repeatability of the surface-enhanced Raman spectroscopy (SERS) substrates are favorable to quantitative analysis. Herein, a quantitative SERS sensor based on constructed self-assembled plasmonic Au@Ag heterogeneous nanocuboids (Au@Ag NCs) monolayer was developed. The sensor was used to quantitatively detect the trace pesticides extracted from pear surfaces and pollutants in fishpond water. Densely packed Au@Ag NCs fabricated into large-scale monolayer films were chemically functionalized using 4-methyl-thiobenzoic acid (4-MBA) at the organic/aqueous interface, in which plentiful nanogaps contribute to increase hotspots. Their sharp corners and edges make the sensor have high SERS performance through providing abundant "hot spots." The obtained optically SERS-based sensor with uniform liquid-state interfacial nanoparticle arrays appeared to have nice SERS performance and uniformity using crystal violet (CV) as a probe molecule. In particular, the proposed SERS sensor was applied for quantitative detection of thiabendazole (TBZ) extracted from pear surfaces and malachite green (MG) in fishpond water down to levels of 0.0105 nM and 0.87 nM for SERS assay respectively. As a result, our proposed SERS quantitative detection strategy is quite preferred to on-site analysis and supervision of contaminant in food samples.

Semiconductor-based photocatalytic hydrogen evolution is considered to be a promising and cost-effective approach to address the environmental issues and energy crisis. It still remains a great challenge to design highly-efficient semiconductor photocatalysts via a facile method. Herein, hierarchically porous hydrangea-like In2S3/In2O3 heterostructures are successfully synthesized via a simple in situ oxidization process. The formed In2S3/In2O3 heterostructures exhibit superior photocatalytic activity to the counterpart In2S3 and In2O3. The boosted photocatalytic performance is ascribed to the formed heterostructures, which greatly facilitate the interfacial charge transfer. Moreover, the formation of hierarchically porous heterostructures increases the number of active sites and improves the permeability, and thus significantly promotes the photocatalytic H2 evolution activity. This work may provide a new insight for designing In2S3-based heterostructures for efficient solar light conversion.

Plant diseases result in 20-40% of agricultural loss every year worldwide. Timely detection of plant diseases can effectively prevent the development and spread of diseases and ensure the agricultural yield. High-throughput and rapid methods are in great demand. This review investigates the advanced application of Raman spectroscopy (RS) and surface-enhanced Raman spectroscopy (SERS) in the detection of plant diseases. The determination of bacterial diseases and stress-induced diseases, fungal diseases, viral diseases, pests in beans, and mycotoxins related to plant diseases using RS and SERS are discussed in detail. Then, biomarkers for RS and SERS detection are analyzed with regard to plant disease diagnosis. Finally, the advantages and challenges are further illustrated. Additionally, potential alternatives are proposed for the challenges. The review is expected to provide a reference and guidance for the use of RS and SERS in plant disease diagnostics.

Background Sonodynamic therapy (SDT) is an emerging non-invasive therapeutic technique. SDT-based cancer therapy strategies are presently underway, and it may be perceived as a promising approach to improve the efficiency of anti-cancer treatment. In this work, multifunctional theranostic nanoparticles (NPs) were synthesized for synergistic starvation therapy and SDT by loading glucose oxidase (GOx, termed G) and 5,10,15,20-tetrakis (4-chlorophenyl) porphyrin) Cl (T (p-Cl) PPMnCl, termed PMnC) in Poly (lactic-co-glycolic) acid (PLGA) NPs (designated as MG@P NPs). Results On account of the peroxidase-like activity of PMnC, MG@P NPs can catalyze hydrogen peroxide (H2O2) in tumor regions to produce oxygen (O2), thus enhancing synergistic therapeutic effects by accelerating the decomposition of glucose and promoting the production of cytotoxic singlet oxygen (1O2) induced by ultrasound (US) irradiation. Furthermore, the NPs can also serve as excellent photoacoustic (PA)/magnetic resonance (MR) imaging contrast agents, effectuating imaging-guided cancer treatment. Conclusion Multifunctional MG@P NPs can effectuate the synergistic amplification effect of cancer starvation therapy and SDT by hypoxia modulation, and act as contrast agents to enhance MR/PA dual-modal imaging. Consequently, MG@P NPs might be a promising nano-platform for highly efficient cancer theranostics. Graphical Abstract

Rational design and controllable synthesis of multiple metal components according to chemical composition and morphology are essential for obtaining desirable electrochemical performance for efficient hydrogen production because of the morphology and synergistic effects of different components. Herein, we report an approach to facilely fabricate bimetal compounds with a well-defined hollow nanoprism structure using a self-templated strategy to synthesize novel hierarchical NiCo-layered double hydroxide (NiCo-LDH) nanosheets as precursors followed by in situ phosphorization. Among the as-synthesized products of different mole ratios of Ni/Co, the NiCo2-B-P nanoprisms that integrate the advantages of a hollow structure, an optimal Ni-Co synergistic effect, and a unique B-doped CoP/Ni2P bimetallic phosphide derived from NiCo-LDH nanosheets exhibit excellent hydrogen evolution reaction (HER) activity in an alkaline solution at 10 mA cm-2 with the lowest overpotential of 78 mV and long-term stability. This study may offer an appropriate structure and compositional design of bimetallic alkaline HER catalysts.

Liliaceae, distributed mainly across the temperate Northern Hemisphere, are of great horticultural, culinary and medical importance, but are also a family with a long history of taxonomic uncertainty. Challenges in accurate species identification persist and phylogenetic relationships among genera in the family continue to be unresolved and/or weakly supported due to the use of limited molecular markers with insufficient variability. Here, nine newly sequenced plastomes for nine Liliaceae genera have been combined with previously published plastome data for this family, providing a total of 86 complete plastid genome sequences covering all 15 currently recognized genera for analyses. All these plastid genomes (146.9–158.3 kb) possess the typical quadripartite structure with conserved genome arrangement and content. Phylogenomic analyses strongly confirm the recognition of four subfamilies: Tricyrtidoideae with four genera; Medeoloideae with two genera; Lilioideae with eight genera and Calochortoideae, for Calochortus alone, as sister to Medeoloideae and Lilioideae. At least ten intergenic spacer regions that may serve as universal markers were identified in the family and, on a finer scale, nine and seven intergenic spacer regions are especially variable in Lilium and Fritillaria, respectively. The intergenic spacer regions rpoB-trnC, trnS-trnG, trnT-psbD and trnT-trnL, which showed high phylogenetic effectiveness, may be the best choices for future phylogenetic, phylogeographic and population genetic studies.

Climate relicts hold considerable importance because they have resulted from numerous historical changes. However, there are major interspecific variations among the ways by which they survived climate changes. Therefore, investigating the factors and timing that affected population demographics can expand our understanding of how climate relicts responded to historical environmental changes. Here, we examined herbaceous hydrangeas of genus Deinanthe in East Asia, which show limited distributions and a remarkable disjunction between Japan and central China. Chloroplast genome and restriction site-associated DNA sequencing revealed that speciation event occurred in the late Miocene (ca. 7-9 Mya) in response to global climate change. Two lineages apparently remained not branched until the middle Quaternary, and afterwards started to diverge to regional population groups. The narrow endemic species in central China showed lower genetic diversity (He = 0.082), as its population size rapidly decreased during the Holocene due to isolation in montane refugia. Insular populations in the three Japanese islands (He = 0.137-0.160) showed a genetic structure that was inconsistent with sea barriers, indicating that it was shaped in the glacial period when its range retreated to coastal refugia on the exposed sea floor. Demographic modelling by stairway-plot analysis reconstructed variable responses of Japanese populations: some experienced glacial bottlenecks in refugial isolation, while post-glacial range expansion seemingly exerted founder effects on other populations. Overall, this study demonstrated the involvement of not just one, but multiple factors, such as the interplay between climate changes, geography, and other population-specific factors, that determine the demographics of climate relicts.

A two-stage alcoholysis was developed for improved conversion of furfural residue (FR) into levulinic acid (LA) and methyl levulinate (ML). Mixed acids including 0.01 M of H2SO4 and Al2(SO4)3 and methanol/water (50/50 v/v%) were identified as the suitable catalyst and reaction medium. The optimum alcoholysis conditions were 198 °C and 1.5 h for the 1st stage and then 163 °C and 1.3 h for the 2nd stage, and the maximum total yield of LA and ML can reach 25.64%. The reaction kinetics and possible conversion pathways for ML and LA production were proposed. On the basis, HCOOH/H2O2 pretreatment was screened for the pretreatment of FR, which increased the cellulose content of FR from 40.01 to 71.91%. The maximum total yield of LA and ML from pretreated FR was 44.96% under the optimum conditions of 195 °C and 1.9 h for the 1st stage and then 166 °C and 1.1 h for the 2nd stage, which was 16.09% higher than that of isothermal alcoholysis. The reusability tests showed that the Al2(SO4)3 was stable and can be reused at least 5 times. This study developed a new method for high-value utilization of FR and cleaner production of LA and ML.

Vacancy engineering has attracted intensive attention owing to its great influence on the performance of photocatalysts. So far it still remains a big challenge to controllably modulate various vacancies co-existing in a photocatalyst and unveil the resultant influence mechanism. Herein, the model catalysts of ZnS nanoplates with vacancy defects of VS and VZn–VS–VZn are successfully prepared via a facile annealing approach and are systematically investigated by various techniques. The ZnS nanoplates with more VS defects show much higher photoreduction activity than those with more VZn–VS–VZn defects. The detailed mechanism is elucidated based on the influence of different vacancy defects on the adsorption and activation of the reactants and desorption of the reduction products, as well as on the separation of charge carriers. The reason that ZnS with different majority defects exhibits different photoreduction selectivity is explained according to the differences in the adsorption/desorption among CO2, H2O, H2 and CO.

A highly selective and sensitive photoelectrochemical (PEC) detection method has been developed for the analysis of copper (Cu2+) ions using nanoflower-like ZnO@CdS heterojunctions, of which ZnO was first in situ grown onto the indium tin oxide electrodes by a hydrothermal method and then coated with CdS through the chemical bath deposition route. It was discovered that the ZnO@CdS heterojunction so formed could serve as a photosensitive catalyst with improved charge separation for visible-light-driven PEC responses. Enhanced visible-light harvesting of nanocomposites could also be expected with CdS as the visible-light sensitizer. Furthermore, the introduction of Cu2+ ions could cause a rational decrease in the photocurrents of nanocomposites through the specific interaction between CdS and Cu2+ ions. A ZnO@CdS heterojunction-based PEC sensor was thereby developed for the detection of Cu2+ ions in blood in the linear concentrations ranging from 0.50 to 80 nM, with a limit of detection of 0.18 nM. Such a heterojunction-based PEC detection platform constructed using two photocatalytic materials with matched band structures are promising for a wide range of applications for sensing Cu2+ ions in clinical diagnostics, food monitoring, and environmental analysis.

Lightweight, high-strength, and multifunctional polymer composite foams are urgently needed in numerous high-tech areas. Herein, we proposed a facile, clean, and energy-saving strategy to prepare the microcellular polystyrene/carbon nanotube (PS/CNT) composite foams with segregated conductive networks by an ingenious combination of microwave-assisted foaming and welding of expandable PS beads. The properties (e.g., expansion ratio, cellular structure, electrical conductivity, and fusion strength) of composite foams can be readily tailored by changing the CNT content and irradiation parameters. Benefiting from the unique structure of the microporous PS phases embedded in the conductive CNT networks, the 3D geometric PS/CNT foam part with a density of 0.095 g cm−3 showed an ultralow percolation threshold of 0.0014 vol% and a high specific electromagnetic interference shielding effectiveness (EMI SE) of 211.5 dB cm3 g−1 at 12.4 GHz with only 0.046 vol% CNT loading. The material presented an absorption-dominant shielding feature due to the synergistic action of the perfect CNT networks and the microcellular structure in PS beads. More importantly, the intense microwave sintering induced sufficient interdiffusion and entanglement across the interfacial regions among neighboring PS beads, thus providing the composite foams with a significantly enhanced compression stress of 7.1 MPa and a tensile strength of 2.2 MPa. Consequently, this study might offer a promising approach to manufacture high-performance and multifunctional composite foams for wearable electronic applications.

The thermally activated delayed fluorescence (TADF) emitters based on donor-acceptor (D-A) configuration were continuously developed in the past few years, whereas an unsymmetrical TADF emitter with A-D-A' configuration has never been reported. Herein, an A-D-A' type TADF emitter of TRZ-SBA-NAI was firstly developed by simultaneously integrating 2-phenyl-1H-benzo[de]isoquinoline-1,3(2H)-dione and 2,4,6-triphenyl-1,3,5-triazine acceptors into a spirobiacridine donor core. Due to the coexistence of double charge-transfer excited states, TRZ-SBA-NAI displayed dual emission containing a dominant orange-red emission and an anti-Kasha's rule sky-blue emission shoulder in solution. As doped into the host matrix, TRZ-SBA-NAI only exhibited an orange-red emission, together with a high photoluminescence quantum yield of 87%. The linear molecular shape imparted TRZ-SBA-NAI with a high horizontal dipole ratio of 88%. As a result, the TRZ-SBA-NAI based devices achieved a record-high external quantum efficiency of 31.7% with an electroluminescence peak at 593 nm. This finding not only enriches the diversity in TADF molecular design, but also unlocks the huge potential of A-D-A' type TADF emitters for excellent device performance.

A high-throughput and selective fluorimetric platform has been constructed for the analysis of ammonia in blood by using a polymer-stabilized metal-organic framework (MOF) of porous NH2-MIL-125, which was coated onto a wettable microwells array constructed on an indium tin oxide (ITO) substrate. It was found that the nitrogen plasma treatment for the ITO substrate could create a super-hydrophilic interface that combined with the hydrophobic pattern yielded a wettable microwells array, enabling the condensation-based enrichment of targets from the sample droplets. Moreover, the NH2-MIL-125 MOF encapsulated using polymers could be firmly coated onto the microwells to act as fluorescent probes for sensing NH3 with enhanced responses. In addition, the use of the polymer polyvinyl pyrrolidone could protect and stabilize the crystals of NH2-MIL-125 probe in aqueous media, revealing the improved hydrophilicity and significantly depressed signal background. The as-developed fluorimetric platform, containing a MOF-coated microwells array, can enable the detection of ammonia in blood, with concentrations ranging linearly from 0.10 to 300 μM. More importantly, this plasma treatment-based fabrication route may hold promise for designing different wettable microwells arrays for the high-throughput detection of multiple targets in the fields of biomedical analysis and environmental monitoring.

Efficient therapeuic proteins' delivery into mammalian cells and subcellular transport (e.g., fast escape from endolysosomes into cytoplasm) are two key biological barriers that need to be overcome for antigen-based immunotherapy and related biomedical applications. For those purposes, we designed a novel kind of photoresponsive polypeptide-glycosylated poly(amidoamine) (PAMAM) dendron amphiphiles (PGDAs), and their synthesis, UV-responsive self-assembly, and triggered ovalbumin (OVA) release have been fully investigated. The highly anisotropic PGDA4 with a glycosylated second-generation PAMAM dendron self-assembled into stable polypeptide vesicles (polymersomes) within 20-50 wt % water, which exhibited UV-responsive reassembly, dynamic binding with a lectin of concanavalin A, and an accelerated OVA release in vitro. Moreover, upon 365 nm UV irradiation, the self-assembled polymersomes of those glycopolypeptides were transformed into micellar aggregates in aqueous solution at pH 7.4 but disassembled completely at pH 5. The OVA-loaded polymersomes could efficiently deliver OVA into RAW264.7 cells and achieve enhanced endolysosomes escape upon UV irradiation, as revealed by flow cytometry and confocal laser scanning microscopy (CLSM). Furthermore, the enzyme-linked immunosorbent assay (ELISA) showed that the blank sugar-coated polypeptidosomes activated a high level of tumor necrosis factor α (TNF-α) of 468 pg/mL, playing a better role of immune adjuvant for activating the macrophages. Upon the UV irradiation with a dose of 3 J/cm2, the OVA-loaded polymersomes could further stimulate RAW264.7 and enhance the TNF-α level by about 45%. Consequently, this work provides a versatile platform to construct photosensitive and sugar-coated polymersomes of glycopolypeptides that have potential applications for protein delivery, immune adjuvant, and antigen-based immunotherapy.

Crystal facet engineering provides a promising approach to tailor the performance of catalysts because of the close relationship between the photocatalytic activity and the surface atomic and electronic structures. An in-depth understanding mechanism of crystal facet-dependent CO2 photoreduction is still an open question. Herein, two different types of porous ZnO nanocatalysts are used as model photocatalysts for the investigation, which are, respectively, with exposed {110} and {001} facets. The porous ZnO with an exposed {110} facet exhibits superior photocatalytic activity to the one with the {001} facet. Various influencing factors have been thoroughly studied both theoretically and/or experimentally, including light harvesting (i.e., band gap), reduction capability (potential of conduction band), crystallinity, CO2 adsorption ability, CO2 activation, and charge separation. The major influencing factors are eventually figured out based on the experimental and calculation results. The product selectivity and the influence of the hole scavenger can be explained too. Our work may pave a way for directing the future rational design of efficient photocatalysts for CO2 reduction.

A visible-light photoredox-catalyzed formal [5 + 1] cycloaddition of N-tosyl vinylaziridines with difluoroalkyl halides as unique C1 synthons was developed. The procedure provides an efficient and practical method to synthesize diverse pyridines in moderate to good yields. The reaction underwent a radical-initiated kinetically controlled ring-opening of vinylaziridines and involved a key α,β-unsaturated imine intermediate, followed by an E2 elimination, a 6π electrocyclization, and defluorinated aromatization.

Iron walnut, Juglans sigillata Dode, restricted to southwestern China, has its centre of distribution in Yunnan Province which has a varied climate, geography and rich plant diversity. Yunnan contains abundant J. sigillata germplasm. In this study, a provincial-scale set of walnut germplasm resources (14 populations comprising 1122 individuals) was evaluated for genetic diversity based on 20 simple sequence repeat (SSR) loci. The number of SSR alleles per locus ranged from 7 to 27, with an average of 17.55. Mean allelic richness and mean private allelic richness ranged from 3.40 to 4.62 and 0.11 to 0.36, with average of 3.93 and 0.30, respectively. Expected heterozygosity (He) varied from 0.26 to 0.78, with an average of 0.57. Polymorphism information content ranged from 0.22 to 0.79, with an average of 0.57. Genetic differentiation (FST) was 0.05, indicating that only 5% of total genetic variability was inter-populational, a finding supported by an analysis of molecular variance and STRUCTURE analysis. Relatively high gene flow (Nm = 6.70) was observed between populations. A unweighted pair-group method with arithmetic analysis classified the 14 populations into two major groups. Mantel testing uncovered a significant correlation between geographic distance and genetic distance (r = 0.33, P = 0.04). Overall, the research revealed a moderately high level of genetic diversity in the germplasm and low genetic differentiation among populations, which showed great potential for further development and exploitation of this resource.

Edge computing, an emerging computing paradigm pushing data computing and storing to network edges, enables many applications that require high computing complexity, scalability, and security. In the big data era, one of the most critical applications is multiparty learning or federated learning, which allows different parties to collaborate with each other to obtain better learning models without sharing their own data. However, there are several main concerns about the current multiparty learning systems. First, most existing systems are distributed and need a central server to coordinate the learning process. However, such a central server can easily become a single point of failure and may not be trustworthy. Second, although quite a few schemes have been proposed to study Byzantine attacks, a very common and challenging kind of attack in distributed systems, they generally consider the scenario of learning a global model. However, in fact, all parties in multiparty learning usually have their own local models. The learning methods and security issues, in this case, are not fully explored. In this article, we propose a novel blockchain-empowered decentralized secure multiparty learning system with heterogeneous local models called BEMA. Particularly, we consider two types of Byzantine attacks, and carefully design “off-chain sample mining” and “on-chain mining ” schemes to protect the security of the proposed system. We theoretically prove the system performance bound and resilience under Byzantine attacks. The simulation results show that the proposed system obtains comparable performance with that of conventional distributed systems, and bounded performance in the case of Byzantine attacks.

Band engineering based on the construction of solid solutions is an effective approach to enhance the efficiency of semiconductor photocatalysts, via which the balance between light absorption and driving force can be well achieved by continuously tuning the band structure. Here the ZnS1–xSex nanobelt solid solutions have been prepared via thermal treatment of ZnS1–xSex(en)0.5 precursors. The compositions are adjusted by changing the mole ratio of Se to S powder in the starting materials, resulting in continuously modulating the alignment of energy levels of the obtained solid solutions. The band structure is also studied via theoretical calculation. Accordingly, the light harvesting can be tuned too, as confirmed by the UV-vis absorption spectra. XPS valence spectra are used to determine the valence band maximum. Transient photoluminescence spectra are employed to study the separation of photogenerated charge carriers. BET specific surface area and CO2 adsorption isotherms of different catalysts are measured. The obtained ZnS1–xSex nanobelts exhibit different photocatalytic activity for solar-fuel production, dependent on many factors like the light harvesting and alignment of energy levels. The related mechanism is studied in detail.

Celtis is a Cannabaceae genus of 60–70 species of trees, or rarely shrubs, commonly known as hackberries. This woody genus consists of very valuable forest plants that provide important wildlife habitat for birds and mammals. Although previous studies have identified its phylogenetic position, interspecific relationships within Celtis remain unclear. In this study, we generated genome skimming data from five Celtis species to analyze phylogenetic relationships within the genus and develop genome resources. The plastomes of Celtis ranged in length from 158,989 bp to 159,082 bp, with a typical angiosperm quadripartite structure, and encoded a total of 132 genes with 20 duplicated in the IRs. Comparative analyses showed that plastome content and structure were relatively conserved. Whole plastomes showed no signs of gene loss, translocations, inversions, or genome rearrangement. Six plastid hotspot regions (trnH-psbA, psbA-trnK, trnG-trnR, psbC-trnS, cemA-petA and rps8-rpl14), 4097 polymorphic nuclear SSRs, as well as 62 low or single-copy gene fragments were identified within Celtis. Moreover, the phylogenetic relationships based on the complete plastome sequences strongly endorse the placement of C. biondii as sister to the ((((C. koraiensis, C. sinensis), C. tetrandra), C. julianae), C. cerasifera) clade. These findings and the genetic resources developed here will be conducive to further studies on the genus Celtis involving phylogeny, population genetics, and conservation biology.

Organic-inorganic hybrid materials have drawn increasing attention as photothermal agents in tumor therapy due to the advantages of green synthesis, high loading efficiency of hydrophobic drugs, facile incorporation of theranostic iron, and excellent photothermal efficiency without inert components or additives. Herein, we proposed a strategy for biomimetic engineering-mediated enhancement of photothermal performance in the tumor microenvironment (TME). This strategy is based on the specific characteristics of organic-inorganic hybrid materials and endows these materials with homologous targeting ability and photothermal stability in the TME. The hybrid materials perform the functions of cancer cells to target homolytic tumors (acting as "artificial nanotargeted cells (ANTC)"). Inspired by the pH-dependent disassembly behaviors of tannic acid (TA) and ferric ion (FeIII) and subsequent attenuation of photothermal performance, cancer cell membranes were self-deposited onto the surfaces of protoporphyrin-encapsulated TA and FeIII nanoparticles to achieve ANTC with TME-stable photothermal performance and tumor-specific phototherapy. The resulting ANTC can be used as contrast agents for concurrent photoacoustic imaging, magnetic resonance imaging, and photothermal imaging to guide the treatment. Importantly, the high loading efficiency of protoporphyrin enables the initiation of photodynamic therapy to enhance photothermal therapeutic efficiency, providing antitumor function with minimal side effects.

The hollow morphology of photocatalysts significantly affects the light absorption, scattering, and charge separation ability. However, the mechanism that dictates the interaction between the light...

Saxitoxin (STX) as one of the most harmful and typical paralytic shellfish toxins, is posing a serious threat to environmental and human health, thus it is essential to develop a sensitive and reliable analytical method for STX detection. Herein, we proposed a strategy for rapid and sensitive detection of STX with surface-enhanced Raman spectroscopy (SERS), by employing cysteine modified gold nanoparticles (Cys-AuNPs) as SERS probe to capture STX molecules through electrostatic interactions and multiple hydrogen bonds between Cys and STX molecules. Moreover, the XPS and zeta potential results indicated that Cys could bond to AuNPs through Au-S bonds and the addition of STX could induce the efficient aggregation of Cys-AuNPs owing to the presence of electrostatic interactions and multiple hydrogen bonds between Cys and STX molecules. Furthermore, considering the high sensitivity and stability of the dynamic surface-enhanced Raman spectroscopy (D-SERS) strategy with the formation of a 3D hotspot matrix, the highly sensitive detection of STX was realized to a level of 1 × 10-7 M by using the D-SERS strategy. Consequently, Cys-AuNPs as high affinity substrates can provide high sensitivity for the detection of STX through the D-SERS strategy. Graphical abstract.

Due to high toxicity to mammals and hazard to the ecosystem, parathion has been banned or limited for use in many countries. It is essential to ensure food safety by parathion suspecting. On-site testing, as a critical component of the food chain safe system, plays a major role in the protection of food safety and human health. In this study, based on monoclonal antibody (Mab), a rapid and sensitive quantum dot submicrobead–based immunochromatographic assay (QB-ICA) was developed for the on-site determination of parathion in agricultural products. The established QB-ICA exhibited good linearity over the range of parathion from 0.7 to 13.0 ng mL−1, with half inhibitory concentration (IC50) of 2.48 ng mL−1 and visual detection limits of 6.25 ng mL−1. The testing process could be accomplished within 15 min, and no cross-reactivities with other organophosphorus pesticides were observed. Three kinds of agricultural products (rice, vegetable, and apple) were spiked and analyzed via QB-ICA for method validation; meanwhile, the comparison was conducted between QB-ICA and gas chromatography (GC). The results revealed that the recovery ranged from 85.23 to 111.4%, with the coefficient of variations (CV) less than 11%, suggesting that the developed QB-ICA is practical and reliable for use. This study provides an alternative approach for on-site detection of parathion, which shows great promise to be further used in the surveillance of food and the environment.

We consider the market mechanism to sell two types of products, A and B, to a set of buyers $$I=\{1, 2, \ldots , n\}$$ . The amounts of products are $$m_A$$ and $$m_B$$ respectively. Each buyer i has his information including the budget, the preference and the utility function. On collecting the information from all buyers, the market maker determines the price of each product and allocates some amount of product to each buyer. The objective of the market maker is designing a mechanism to maximize the total utility of the buyers in satisfying the semi market equilibrium. In this paper, we show that this problem is NP-hard and give an iterative algorithm with the approximation ratio 1.5. Moreover, we introduce a PTAS for the problem, which is an ( $$1+\epsilon $$ )-approximation algorithm with the running time $$O(2^{1/\epsilon }+n\log n)$$ for any positive $$\epsilon $$ .

Aenasius bambawalei is one of the most important parasitoids attacking Phenacoccus solenopsis. Studies were conducted to measure and compare its developmental rate, and parasitism using A. bambawal...

Objective To construct prostate-specific membrane antigen (PSMA)-targeting, indocyanine green (ICG)-loaded nanobubbles (NBs) for multimodal (ultrasound, photoacoustic and fluorescence) imaging of prostate cancer. Methods The mechanical oscillation method was used to prepare ICG-loaded photoacoustic NBs (ICG NBs). Then, PSMA-binding peptides were connected to the surface of ICG NBs using the biotin-avidin method to make targeted photoacoustic NBs, namely, PSMAP/ICG NBs. Their particle sizes, zeta potentials, and in vitro ultrasound, photoacoustic and fluorescence imaging were examined. Confocal laser scanning microscopy and flow cytometry were used to detect the binding ability of the PSMAP/ICG NBs to PSMA-positive LNCaP cells, C4-2 cells, and PSMA-negative PC-3 cells. The multimodal imaging effects of PSMAP/ICG NBs and ICG NBs were compared in nude mouse tumor xenografts. Results The particle size of the PSMAP/ICG NBs was approximately 457.7 nm, and the zeta potential was approximately -23.5 mV. Both confocal laser scanning microscopy and flow cytometry confirmed that the PSMAP/ICG NBs could specifically bind to both LNCaP and C4-2 cells, but they rarely bound to PC-3 cells. The ultrasound, photoacoustic and fluorescence imaging intensities of the PSMAP/ICG NBs in vitro positively correlated with their concentrations. The ultrasound and photoacoustic imaging effects of the PSMAP/ICG NBs in LNCaP and C4-2 tumor xenografts were significantly enhanced compared with those in PC-3 tumor xenografts, which were characterized by a significantly increased duration of ultrasound enhancement and heightened photoacoustic signal intensity (P < 0.05). Fluorescence imaging showed that PSMAP/ICG NBs could accumulate in LNCaP and C4-2 tumor xenografts for a relatively long period. Conclusion The targeted photoacoustic nanobubbles prepared in this study can specifically bind to PSMA-positive prostate cancer cells and have the ability to enhance ultrasound, photoacoustic and fluorescence imaging of PSMA-positive tumor xenografts. Photoacoustic imaging could visually display the intensity of the red photoacoustic signal in the tumor region, providing a more intuitive imaging modality for targeted molecular imaging. This study presents a potential multimodal contrast agent for the accurate diagnosis and assessment of prostate cancer.

Using the hybridoma cells 2D3 which secrete anti-Cry1 monoclonal antibody as DNA source, the variable region genes of heavy chain (VH) and light chain (VL) were amplified and assembled as single-chain variable fragment (scFv). The scFv-2D3 genes were cloned into pET-26b vectors for expression and scFv-2D3 expression was identified by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and western blot (WB). The activity of scFv-2D3 was determined by indirect enzyme-linked immune sorbent assay (ELISA). As a result, scFv-2D3 was successfully constructed and expressed, with specific recognition activities to the Cry1 toxins. Homologous modeling and molecular docking results showed that VL was the main combination domain of scFv-2D3 with Cry1 toxins. Therefore, VH and VL were separately expressed and then assayed by indirect ELISA, indicating that both VH and VL could recognize the Cry1 toxin, and the activity of VL was higher than that of VH, which confirming the molecular docking result. Afterward, double light chain antibodies (VL-VL) were designed and produced, and the binding activities of VL-VL against Cry1Aa, Cry1Ab, and Cry1Ac were significantly enhanced with OD450 values improved 1.18, 1.44, and 1.22 times, respectively, compared with scFv-2D3. For VL-VL-based double antibody sandwiched ELISA (DAS-ELISA), the limits of detection (LOD) and limits of quantification (LOQ) were 10.5–16.0 and 12.8–21.5 ng mL−1 for seven Cry1 toxins, respectively, which were lower than scFv-2D3 (14.8–29.2 and 39.0–50.3 ng mL−1). The results were beneficial to developing high-throughput and high-sensitive immune-detecting technology for Cry1 toxins.

Constructing hierarchical superstructures to achieve comparable complexity and functions to proteins with four-level hierarchy is challenging, which relies on the elaboration of novel building blocks with complex structures. We present a series of catenated cages with unique structural complexity and tailorability. The rational design was realized as such: A catenane of two symmetric cages (CSC), CSC-1, with all rigid imine panels was converted to a catenane of two dissymmetric cages (CDC), CDC-1, with two exterior flexible amine panels, and CDC-5 was tailored from CDC-1 by introducing an additional methyl group on each blade to increase lateral hindrance. CDC-1s with the most irregular and flexible configuration formed supramolecular dimers, which self-organized into 3D continuous wavelike plank with a three-level hierarchy, previously undiscovered by conventional building blocks. A drastically different 3D triclinic crystalline phase with a four-level hierarchy and trigonal phase with a three-level hierarchy were constructed of distorted CSC-1s and the most symmetric CDC-5s, respectively. The wavelike plank exhibited the lowest order, and the triclinic phase had a lower order than the trigonal phase which had the highest order. It correlates with the configuration of the primary structures, namely, the most disordered shape of CDC-1, the low-order configuration of CSC-1, and the most ordered geometry of CDC-5. The catenated cages with subtle structural differences therefore provide a promising platform for the search of emerging hierarchical superstructures that might be applied to proton conductivity, ferroelectricity, and catalysis.

Lithium–oxygen (Li–O2) batteries, profiting by their super high theoretical energy density and oxygen-breathing electrodes, have attracted extensive concern. The synthesis of the electrode material...

BACKGROUND: Methyl levulinate (ML) is a promising green candidate for bio‐based diesel fuels and fuel additives. An effective method for synthesizing ML from levulinic acid (LA) catalyzed by cheap metal salt catalyst under mild conditions was developed. A series of metal salts were screened for the synthesis of ML from LA, and aluminum chloride was identified as a suitable catalyst for this process. RESULTS: The effects of catalyst loading, the molar ratio of methanol to LA, reaction temperature and reaction time on LA conversion and ML yield were investigated. The response surface method was used to optimize the process, and the model validation experiment showed that the predicted values corresponded well with the actual ones. Under the optimum conditions of reaction temperature 343 K, reaction time 1.5 h, aluminum chloride 1.14 g and molar ratio of methanol to LA 8:1, a high ML yield of 95.0 mol% could be obtained. Moreover, a kinetic model was proposed to evaluate the reaction process at a temperature range of 30–70 °C. The first‐order pseudo model was considered most suitable (R² > 0.99), and the activation energy of the reaction Eₐ was estimated to be 32.28 kJ mol⁻¹. Investigation of the reuse of the catalyst revealed that it retained good catalytic activity after repeated use for ten times. CONCLUSION: A green and efficient process of ML production from LA catalyzed by the metal salt aluminum chloride was developed. © 2020 Society of Chemical Industry

Heteroatom doping is one of the effective ways to improve the catalytic performances of nanozymes. In the present work, the plasma-assisted controllable doping of nitrogen (N) into MoS2 nanosheets has been initially proposed, resulting in efficient nanozymes. The so-obtained nanozymes were characterized separately by TEM, XRD, XPS, and FTIR. It was discovered that the resulting N-doped MoS2 nanosheets could present dramatically enhanced peroxidase-like catalytic activities depending on the plasma treatment time. Particularly, that with the 2-min treatment could display the highest catalytic activity, which is over 3-fold higher than that of pristine MoS2, that was also demonstrated by the kinetics studies. Herein, the N2 plasma treatment could facilitate the N elements to be doped covalently into MoS2 nanosheets to achieve the increased surface wettability and affinity of nanozymes for the improved access of the electrons and substrates of catalytic reactions. More importantly, the covalent doping of N elements into MoS2 nanosheets with a lower Fermi level, as evidenced by the DFT analysis, could facilitate the promoted electron transferring, resulting in the enhanced catalysis of N-doped MoS2 nanozymes, in addition to the high catalytic stability in water. Such a controllable plasma treatment strategy may open a new door toward the large-scale applications for doping heteroatoms into various nanozymes with improved catalysis performances.

The kinetics, thermodynamics, and volatile products of camphorwood pyrolysis were investigated via thermogravimetry coupled with Fourier transform infrared (FTIR) spectroscopy at multiple heating rates. The kinetic triplets and thermodynamic parameters were estimated via model free combined with the model-fitting approach. The results showed that the pyrolysis of camphorwood in the conversion rate range from 0 to 0.85 might be considered as one-step process. The mean value of the activation energy and pre-exponential factor was 192.63 kJ/mol and 2.38 × 1013 s−1, respectively. The pyrolysis process (0 ≤ α ≤ 0.85) can be described by the three-dimensional diffusion model g(α) = [(1−α)−1/3 – 1]2. Furthermore, the predicted curves of the conversion rate α showed good agreement with the experimental curves. The values of ΔH, ΔG, and ΔS varied little with α and remained positive. In addition, the major gas products released from the camphorwood waste pyrolysis were H2O, methane, CO2, CO, C=O, O–H, C–O–C, and NH3, whose concentration in the order from highest to lowest was C=O > CO2 > O–H > H2O > methane > NH3 > C–O–C > CO. The main conclusions in the present study can provide guidance for the design and optimization of industrial reactor and selection of target biofuels or chemical raw materials.

Considerable efforts have been made to increase the topological complexity of mechanically interlocked molecules over the years. Three-dimensional catenated structures composed of two or several (usually symmetrical) cages are one representative example. However, owing to the lack of an efficient universal synthetic strategy, interlocked structures made up of dissymmetric cages are relatively rare. Since the space volume of the inner cavity of an interlocked structure is smaller than that outside it, we developed a novel synthetic approach with the voluminous reductant NaBH(OAc)3 that discriminates this space difference, and therefore selectively reduces the outer surface of a catenated dimer composed of two symmetric cages, thus yielding the corresponding catenane with dissymmetric cages. Insight into the template effect that facilitates the catenation of cages was provided by computational and experimental techniques.

Two novel series of chalcone-based homoserine lactones were synthesized and their quorum sensing (QS) inhibitory activity was evaluated against Pseudomonas aeruginosa in vitro. Furthermore these compounds’ capacity for modulation of the LasR-dependent quorum sensing system of P. aeruginosa was identified. Among these compounds, (S)-2-((4-(3-(4-bromo-2-fluorophenyl) acryloyl) phenyl) amino)-N-(2-oxotetrahydrofuran-3-yl)acetamide exerted the inhibition of LasR-dependent QS system of P. aeruginosa in contrast to brominated furanone C30. Worthy of particular note, this research has delivered novel potent quorum sensing inhibitors (QSIs), which strongly inhibit the production of virulence factors in a wild type strain of this pathogenic bacterium.

Plant litter can be incorporated into topsoil by a natural process, affecting the soil erosion process. This is a widespread phenomenon in erosion‐prone areas. This study was conducted to investigate the effect of litter incorporation on the process of soil detachment on the Loess Plateau, China. Four common plant litters (Bothriochloa ischaemum L. Keng., Artemisia sacrorum Ledeb., Setaria viridis L. Beauv., and Artemisia capillaris Thunb.) were collected, then incorporated into the silt loam soil at five rates (0.1, 0.4, 0.7, 1.0, and 1.3 kg m⁻²) on the basis of our field investigation. Twenty litter–soil treatments and one bare soil control were prepared. After 50 days of natural stabilization, 30 soil samples of each treatment were collected. We used a flume test to scour the soil samples under six flow shear stress conditions (5.66, 8.31, 12.21, 15.55, 19.15, and 22.11 Pa). The results showed that the different incorporated litter masses and morphological characteristics, such as litter tissue density (ranging from 0.52 to 0.68 g cm⁻³), length density (2.34 to 91.00 km m⁻³), surface area density (LSAD; 27.9 to 674.2 m² m⁻³), and volume ratio (0.003 to 0.050 m³ m⁻³), caused varied soil detachment capacities (0.043 to 4.580 kg·m⁻²·s⁻¹), rill erodibilities (0.051 to 0.237 s m⁻¹), and critical shear stresses (2.02 to 6.83 Pa). The plant litter incorporated within the soil reduced the soil detachment capacities by 38%–59%, lowered the rill erodibilities by 32%–46%, and increased the critical shear stresses by 98%–193% compared with the bare soil control. The soil containing B. ischaemum (L.) Keng. litter was more resistant to erosion. By comparing different parameters, we found that the contact area between the litter and soil was the main factor affecting the soil detachment process. The soil erosion resistance increased with the increasing contact area between the soil and litter. Furthermore, the litter incorporation effect on rill erodibility can be comprehensively reflected by LSAD (R² = .93; Nash–Sutcliffe efficiency = 0.79), which could be used to adjust the rill erodibility parameter in physical process‐based soil erosion models.

Hybridization chain reaction (HCR) was a significant discovery for the development of nanoscale materials and devices. One key challenge for HCR is the vulnerability to background leakage in the absence of the initiator. Here, we systematically analyze the sources of leakage and refine leak-resistant rule by using molecular thermodynamics and dynamics, biochemical and biophysical methods. Transient melting of DNA hairpin is revealed to be the underlying cause of leakage and that this can be mitigated through careful consideration of the sequence thermodynamics. The transition threshold of the energy barrier is proposed as a testing benchmark of leak-resistance DNA hairpins. The universal design of DNA hairpins is illustrated by the analysis of hsa-miR-21-5p as biomarker when used in conjunction with surface-enhanced Raman spectroscopy. We further extend the strategy for specific signal amplification of miRNA homologs. Significantly, it possibly provides a practical route to improve the accuracy of DNA self-assembly for signal amplification, and that could facilitate the development of sensors for the sensitive detection of interest molecules in biotechnology and clinical medicine.

Transparent polymer electrolytes such as poly(vinyl alcohol)-based H+, Li+, K+, and Na+ gels have been widely used as both an electrolyte and a separator for flexible transparent supercapacitors (FTSCs). However, these gels sandwiched between the electrodes in FTSCs are easily compressed under bending and compression due to their viscous flow behavior, resulting in the deformation of electrode spacing and the unstable capacitance performance. To resolve this issue, herein, we introduce monodispersed polystyrene (PS) microspheres into PVA-LiCl polymer gel electrolytes as spacers to precisely control the electrode spacing during the assembly of FTSCs using single-walled carbon nanotubes/indium tin oxide-polyethylene terephthalate (ITO-PET) or MnO2/multiwalled carbon nanotubes/ITO-PET as transparent electrodes. The electrode spacing could be tuned by varying the diameter of PS microspheres, for example, 20, 40, and 80 μm. More importantly, the PS microsphere spacers protect the gel electrolyte from the squeeze when bending takes place, allowing the stable performance output by FTSCs under a bending state. After repeating bending tests, the capacitance remains 95.6%, indicating the high stability and flexibility of the devices with the assistance of PS microsphere spacers.

Machine learning models are vulnerable to a variety of data perturbation. Recent research mainly focuses on the vulnerability of model training and proposes various model-oriented defense methods to achieve robust machine learning. However, most of the existing research overlooks the vulnerability of model capacity, which is more fundamental for model performance. In this paper, we study an adversarial vulnerability of model capacity caused by the poisoning on the estimation of model hyper-parameters. We further implement this vulnerability catering for the polynomial regression model, on which the evading of model-oriented detection is challenging, to illustrate the effectiveness of the adversarial vulnerability. Extensive experiments on one synthetic and three real-world data sets demonstrate that the vulnerability can effectively mislead the hyper-parameter estimation of the polynomial regression model by poisoning a few numbers of camouflage samples that cannot be detected by model-oriented defense methods.

Atrazine has been widely used as a synthetic herbicide in many countries. Due to its persistence and mobility, atrazine is difficult to eliminate by conventional treatment processes or biodegradation and may cause varying degrees of harm to untargeted organisms and threaten environmental sustainability. In recent years, microbubble ozonation has been reported to accelerate the removal of persistent organic pollutants, but there has been little research on the removal of atrazine using this approach. In this study, microbubble ozonation was shown to enhance the degradation of atrazine under a variety of pH conditions compared to macrobubble ozonation using the same concentration of aqueous ozone. The microbubble surface is usually negatively charged and hydroxyl ions accumulating at the gas–liquid interface can promote the self-decomposition of ozone and the formation of hydroxyl radicals. This promotion of ozone decomposition by microbubbles, together with the effect of microbubble collapse, were the major reasons for the enhanced degradation of atrazine. Common background components in water include organic humic acids, metal ions and inorganic ions. When low concentrations of humic acid or ferrous iron at concentrations similar to residual levels from coagulation processes were added into a pure water system, they exerted a positive effect on removal of atrazine, while the presence of bicarbonate in natural water may inhibit the degradation of atrazine in water treatment plants.

Rapid industrialization and urbanization have contributed to eutrophication of urban landscape water in China. As an important part of aquatic ecosystems, macrophytes have many advantages in controlling eutrophication and algal blooms. In recent years, micro-nanobubble (MNB) aeration has increasingly been used for restoring natural waters suffering from eutrophication, which may affect the growth of macrophytes and thereby affect ecological restoration, but the effect of MNBs on macrophytes has not drawn great attention. In this study, three common species of macrophytes (Echinodorus amazonicus or EA, Echinodorus quadricostatus or EQ and Microsorum pteropus or MP) were grown for 60 days in water aerated with MNBs and their growth was compared to that of the same plants grown with standard macrobubble aeration. The growth of EA and EQ was significantly inhibited by MNB aeration, and was accompanied by various symptoms of senescence (yellowing and chlorophyll degradation, the decrease of photosynthesis rate, carbon fixation and plant growth, and the decline of respiration rate). However, the growth of MP plants was not significantly affected under the same conditions. The final fresh weights (FFWs) of EA, EQ and MP in the presence of high MNB levels were 0.75, 0.83 and 1.05 times those in the macrobubble aeration system; we designate this parameter ratioFFW. We found the initial total antioxidant capacity (T-AOC) of EA and EQ to be 48.00 and 64.67 U mL−1, respectively, markedly lower than that of MP (617.33 U mL−1). The ratioFFW values and other growth indexes of the three plant species were positively correlated with their T-AOC. Macrophytes use their antioxidant defense mechanisms to prevent oxidative damage by ROS, while still allowing exogenous ROS to function as signalling molecules to regulate plant growth and senescence. Premature senescence is a protective mechanism employed when plants are stressed and their growth is consequently inhibited. Our results suggest that instead of positively promoting the growth of dense macrophytes, the MNBs potentially induce damage to water ecosystem.

Earthquake prediction is a very important problem in seismology, the success of which can potentially save many human lives. Various kinds of technologies have been proposed to address this problem, such as mathematical analysis, machine learning algorithms like decision trees and support vector machines, and precursors signal study. Unfortunately, they usually do not have very good results due to the seemingly dynamic and unpredictable nature of earthquakes. In contrast, we notice that earthquakes are spatially and temporally correlated because of the crust movement. Therefore, earthquake prediction for a particular location should not be conducted only based on the history data in that location, but according to the history data in a larger area. In this paper, we employ a deep learning technique called long short-term memory (LSTM) networks to learn the spatio-temporal relationship among earthquakes in different locations and make predictions by taking advantage of that relationship. Simulation results show that the LSTM network with two-dimensional input developed in this paper is able to discover and exploit the spatio-temporal correlations among earthquakes to make better predictions than before.

Lipophilicity, as evaluated by the n-octanol/buffer solution distribution coefficient at pH = 7.4 (log D7.4), is a major determinant of various absorption, distribution, metabolism, elimination, and toxicology (ADMET) parameters of drug candidates. In this study, we developed several quantitative structure–property relationship (QSPR) models to predict log D7.4 based on a large and structurally diverse data set. Eight popular machine learning algorithms were employed to build the prediction models with 43 molecular descriptors selected by a wrapper feature selection method. The results demonstrated that XGBoost yielded better prediction performance than any other single model (RT2 = 0.906 and RMSET = 0.395). Moreover, the consensus model from the top three models could continue to improve the prediction performance (RT2 = 0.922 and RMSET = 0.359). The robustness, reliability, and generalization ability of the models were strictly evaluated by the Y-randomization test and applicability domain analysis. Mor...

A nickel-catalyzed transformation of diazoacetates to α-carbonyl methylene radicals has been disclosed in the presence of hyperoxide using ethanol as a hydrogen source and solvent. This strategy is successfully applied in the formation of indolin-2-ones or 1,4-dicarbonyl compounds from acrylamides or enamides in moderate to good yields. These reactions undergo radical addition onto C-C double bonds followed by a cyclization/oxidation or an oxidation/hydrolysis process, respectively.

Autophagy acts as a pivotal innate immune response against infection. Some virulence effectors subvert the host autophagic machinery to escape the surveillance of autophagy. The mechanism by which pathogens interact with host autophagy remains mostly unclear. However, traditional strategies often have difficulty identifying host proteins that interact with effectors due to the weak, dynamic, and transient nature of these interactions. Here, we found that Enteropathogenic Escherichia coli (EPEC) regulates autophagosome formation in host cells dependent on effector NleE. The 26S Proteasome Regulatory Subunit 10 (PSMD10) was identified as a direct interaction partner of NleE in living cells by employing genetically incorporated crosslinkers. Pairwise chemical crosslinking revealed that NleE interacts with the N-terminus of PSMD10. We demonstrated that PSMD10 homodimerization is necessary for its interaction with ATG7 and promotion of autophagy, but not necessary for PSMD10 interaction with ATG12. Therefore, NleE-mediated PSMD10 in monomeric state attenuates host autophagosome formation. Our study reveals the mechanism through which EPEC attenuates host autophagy activity.

It has been suggested that irreversible adsorption at the gas/liquid interface of bulk nanobubbles will reduce the Laplace pressure, leading to their stability. However, most previous studies have focused on the stability of individual nanobubbles. Bulk nanobubbles are polydispersed suspensions, and gas molecules can diffuse between bubbles, leading to their collective dynamics, which may be crucial to understanding their formation process and stability. In this study, we proposed a mean-field theory for computing the evolution of the size-distribution function of bulk nanobubbles with size-dependent surface tension. We applied this theory to investigate the evolution of bulk nanobubbles with insoluble surfactants pinned at their gas/water interface. The results show that Ostwald ripening can be suppressed when enough surfactants are adsorbed. Bulk nanobubbles can be produced by the shrinkage of microbubbles in an air-saturated solution. The mean stable size is controlled by the amount of surfactants and the initial microbubble concentration; these predictions are qualitatively consistent with the experimental results of micro/nanobubbles produced using the microfluidic method.