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The present work proposes a novel master-alloy pre-hydrogenation powder metallurgy (MAPH) method to fabricate the TC16 (Ti-3Al-5Mo-4.5V) alloy, which overcomes the challenge of low sintering density due to the high percentage of alloying powders (APs) and the presence of Mo element. The relative density of sintered TC16 alloys increases with the Ti-addition in APs, i.e., ∼99.2% and ∼99.4% for sintered TC16 alloys based on pre-hydrogenated 7.5Ti-3Al-5Mo-4.5V (7.5TiMA-Hx) and 12.5Ti-3Al-5Mo-4.5V (12.5TiMA-Hx) powders, respectively. The APs were successfully modified to be brittle and hydrogen-containing, which exhibits similar pressing and sintering characteristics as TiH2powders. The increased relative density could be ascribed to the brittleness of 7.5/12.5TiMA-Hx, in which particles show sharp corners that can form interlocked structures with TiH2particles during pressing. Furthermore, the 7.5/12.5TiMA-Hxand TiH2powder particles release H2and shrink simultaneously during sintering, which minimizes the difference in volume mismatch between particles and promotes elemental diffusion. The sintered TC16-7.5TiMA-Hxalloy achieves excellent mechanical properties, i.e., an ultimate tensile strength of ∼1004.6 MPa, a yield strength of ∼934.2 MPa and an elongation of ∼15.8%, due to the low porosity and acceptable impurity contents. However, the excessive O and N elements in the sintered TC16-12.5TiMA-Hxalloy can induce premature intergranular fracture, resulting in decreased ductility. Therefore, the innovative MAPH technique is promising in obtaining high density sintered Ti alloys with excellent mechanical properties.

Controlled charge flows are fundamental to many areas of science and technology, serving as carriers of energy and information, as probes of material properties and dynamics1and as a means of revealing2,3or even inducing4,5broken symmetries. Emerging methods for light-based current control5–16offer particularly promising routes beyond the speed and adaptability limitations of conventional voltage-driven systems. However, optical generation and manipulation of currents at nanometre spatial scales remains a basic challenge and a crucial step towards scalable optoelectronic systems for microelectronics and information science. Here we introduce vectorial optoelectronic metasurfaces in which ultrafast light pulses induce local directional charge flows around symmetry-broken plasmonic nanostructures, with tunable responses and arbitrary patterning down to subdiffractive nanometre scales. Local symmetries and vectorial currents are revealed by polarization-dependent and wavelength-sensitive electrical readout and terahertz (THz) emission, whereas spatially tailored global currents are demonstrated in the direct generation of elusive broadband THz vector beams17. We show that, in graphene, a detailed interplay between electrodynamic, thermodynamic and hydrodynamic degrees of freedom gives rise to rapidly evolving nanoscale driving forces and charge flows under the extremely spatially and temporally localized excitation. These results set the stage for versatile patterning and optical control over nanoscale currents in materials diagnostics, THz spectroscopies, nanomagnetism and ultrafast information processing.

Exploring dynamic patterns from complex and large-scale networks is a significant and challenging task in graph analysis. One of the most advanced solutions is dynamic graph representation learning, which embeds structural and temporal correlations into a representative vector for each node or subgraph. Existing models have made some successes, such as overcoming the problems of induction for unseen nodes and scalability for large-scale evolving networks. However, these models usually rely on crisp representation learning that is incapable of modeling feature fuzziness and capturing uncertainties in dynamic graphs. While real-world dynamic networks as complex systems always contain non-negligible but inestimable uncertainties in node/link attributes and network topology. These uncertainties may cause the learned representations from crisp models hard to precisely reflect network evolution. To address the issues, we propose a new dynamic graph representation learning model, called FuzzyDGL, which first incorporates fuzzy representation learning to handle the uncertainties in dynamic graphs. Through combining acrlong CDGRL with fuzzy logic, the FuzzyDGL digests both of their advantages. On the one hand, it has flexible model scalability and brilliant inductive capability. On the other hand, it can model feature fuzziness to reduce the impact of uncertainties in dynamic graphs, improving the quality of learned representations. To demonstrate its effectiveness, we conduct two important tasks of network analysis, including link prediction and node classification, over eight real-world datasets. The experimental results show the strong competitiveness and generalization of the FuzzyDGL against a number of baseline models.

The valuation of discounted cash flow (DCF) is one of the most appropriate methods to measure a company’s value, and it is also a fundamental method according to Warren Buffett to value a stock for investment. DCF analysis requires the estimations of the future free cash flow (FCF) and the weighted average cost of capital. However, these factors are often subject to an appraiser’s bias. To obtain a more objective DCF analysis, in this study, we develop a machine learning mechanism: imitation learning, which encompasses a teacher to demonstrate state-action pairs. To facilitate imitation learning, we adopt a guided policy search with the chronological order of a Levy distribution. This distribution can cover the stages of growth, decay, and long fat tail that correspond to a business life cycle. In this way, learning the trajectory of FCF can optimize the fitness between the FCF and the chronological order of a Levy distribution. The fitness achieved allows us to monitor the data by fitting the chronological order for the correct stage. The results show that regarding the Sharpe ratio and precision of DCF valuation, our approach outperforms the popular classification models - random forest and long short-term memory network. Code is available at https://github.com/YuanLongPeng/DCFValuation. Note to Practitioners—Appraisers own knowledge for valuation of stocks to project FCFs and WACC. The knowledge has a broad spectrum, such as prospect of economic growth and competition in the industry. Threat of substitute products. This study proposed a method to automate the process of valuation by learning FCFs and WACC from data. The result of valuation is reproducible and free of the bias of appraisers.

The selective catalytic reduction (SCR) NH3catalyst is mainly used in industrial production and automobile exhaust cleaning. In this study, a novel α%Fe2O3/ZrTiO4(α=0, 8, 12, 15) catalyst was prepared by the coprecipitation impregnation method. The results show that the NOxconversion rate of 12%Fe2O3/ZrTiO4catalyst with the optimal composition is high above 80% at 250−400 °C, close to 100% at 300 °C, and N2selectivity is high above 90% at 200−450 °C. The redox properties, surface acidity, and Oβ/(Oα+ Oβ) ratio of ZrTiO4catalysts are improved after loading Fe2O3on the ZrTiO4surface, which is attributed not only to the porous structure of α%Fe2O3/ZrTiO4catalyst but also to the synergistic interaction between the active component Fe2O3and the support ZrTiO4. In addition, in-situDRIFT reactions show that the NH3-SCR reaction of 12%Fe2O3/ZrTiO4catalyst follows the Eley-Rideal mechanism. A clear reaction mechanism is conducive to a deeper understanding of the reaction process of NOxconversion during SCR. This work provides a feasible strategy for Fe-based SCR catalysts to replace V-based catalysts in the medium temperature range in the future.

Developing effective strategies to prevent diarrhea and associated-gut disorders in mammals has gained great significance. Owing to the many health benefits provided by the commensal microbiota of the intestinal tract, such as against environmental perturbation, we explored the host phenotype-associated microbes and their probiotic potential. Based on the observations that the chronic heat stress-exposed weaned piglets present as heat stress-susceptible (HS-SUS) or heat stress-resistant (HS-RES) individuals, we confirmed the phenotypic difference between the two on growth performance (P < 0.05), diarrhea index (P < 0.001), intestinal heat shock protein 70 (HSP70) regulation (P < 0.01), and inflammatory responses (P < 0.01). By comparing the gut microbiome using 16S rRNA gene sequencing and KEGG functional analysis, we found that Lactobacillus johnsoniiexhibited significantly higher relative abundance in the HS-RES piglets than in the HS-SUS ones (P < 0.05). Further experiments using a mouse model for chemical-induced inflammation and intestinal injury demonstrated that oral administration of a representative L. johnsoniiN5 (isolated from the HS-RES piglets) ameliorated the clinical and histological signs of colitis while suppressing intestinal pro-inflammatory cytokines TNF-α and IL-6 production (P < 0.05). We found that N5 treatment enhanced tight junction proteins ZO-1 and occludin and cytoprotective HSP70 levels under physiological condition and restored their mucosal expressions in colitis (P < 0.05). In support of the high production of the anti-inflammatory cytokine IL-10, N5 promoted the intestinal Peyer's patches MHCII+and CD103+dendritic cell populations (P < 0.05), increased the regulatory T (Treg) cell numbers (P < 0.05), and decreased the Th17 population and its IL-17a production under physiological condition and during colitis (P < 0.01). Our results shed light on understanding the interaction between commensal Lactobacillusand the host health, and provide L. johnsoniiN5 as an alternative to antibiotics for preventing diarrhea and intestinal diseases.

Clique is one of the most fundamental models for cohesive subgraph mining in network analysis. Existing clique model mainly focuses on unsigned networks. However, in real world, many applications are modeled as signed networks with positive and negative edges. As the signed networks hold their own properties different from the unsigned networks, the existing clique model is inapplicable for the signed networks. Motivated by this, we propose the balanced clique model that considers the most fundamental and dominant theory, structural balance theory, for signed networks. Following the balanced clique model, we study the maximal balanced clique enumeration problem (${\mathsf {MBCE}}$MBCE) which computes all the maximal balanced cliques in a given signed network. Moreover, in some applications, users prefer a unique and representative balanced clique with maximum size rather than all balanced cliques. Thus, we also study the maximum balanced clique search problem (${\mathsf {MBCS}}$MBCS) which computes the balanced clique with maximum size. We show that ${\mathsf {MBCE}}$MBCE problem and ${\mathsf {MBCS}}$MBCS problem are both NP-Hard. For the ${\mathsf {MBCE}}$MBCE problem, a straightforward solution is to treat the signed network as two unsigned networks and leverage the off-the-shelf techniques for unsigned networks. However, such a solution is inefficient for large signed networks. To address this problem, in this paper, we first propose a new maximal balanced clique enumeration algorithm by exploiting the unique properties of signed networks. Based on the new proposed algorithm, we devise two optimization strategies to further improve the efficiency of the enumeration. For the ${\mathsf {MBCS}}$MBCS problem, we first propose a baseline solution. To overcome the huge search space problem of the baseline solution, we propose a new search framework based on search space partition. To further improve the efficiency of the new framework, we propose multiple optimization strategies regarding to redundant search branches and invalid candidates. We conduct extensive experiments on large real datasets. The experimental results demonstrate the efficiency, effectiveness and scalability of our proposed algorithms for ${\mathsf {MBCE}}$MBCE problem and ${\mathsf {MBCS}}$MBCS problem.

A three-dimensional reduced graphene oxide aerogel modified by sulfamic acid and ethylenediamine was prepared via one-step reduction self-assembly under atmospheric pressure within 90 °C heating constantly. The adsorption efficiency of palladium (II) was ~ 97.0% at pH 11 within 50 min by the prepared composite. While the composite exhibited adsorption for platinum (IV) at acid condition, giving a rising to an adsorption efficiency was 61.7% at pH 5. Only 25.8% adsorption efficiency of platinum (IV) was found at pH 11, and 17.0% adsorption efficiency of palladium (II) was obtained at pH 5. The adsorption capacity of the composite for palladium (II) was 80 μg mg−1above, and the adsorption capacity of the composite for platinum (IV) was ~ 160 μg mg−1. The obtained palladium (II) and platinum (IV) can be eluted by urea and surfactant from the surface of the composite, respectively. Understanding the mechanism of the adsorption/desorption between palladium (II)/platinum (IV) and the composite, explored a promising way for recycling and enrichment of noble metal at a low concentration.

In this paper we are concerned with Trefftz discretizations of the time-dependent Maxwell equations in anisotropic media in three-dimensional domains. We propose a class of space–time Trefftz DG methods, which include the Trefftz variational formulation from Egger et al. (2015). We prove the error estimates of the approximate solutions with respect to the meshwidth and the condition number of the coefficient matrices. Furthermore, we propose the global Trefftz DG method combined with local DG methods to solve the time-dependent linear nonhomogeneous Maxwell equations in anisotropic media. The numerical results verify the validity of the theoretical results, and show that the resulting approximate solutions possess high accuracy. [ABSTRACT FROM AUTHOR]

Motivated by the advancing computational capacity of distributed end-user equipment (UE), as well as the increasing concerns about sharing private data, there has been considerable recent interest in machine learning (ML) and artificial intelligence (AI) that can be processed on distributed UEs. Specifically, in this paradigm, parts of an ML process are outsourced to multiple distributed UEs. Then, the processed information is aggregated on a certain level at a central server, which turns a centralized ML process into a distributed one and brings about significant benefits. However, this new distributed ML paradigm raises new risks in terms of privacy and security issues. In this article, we provide a survey of the emerging security and privacy risks of distributed ML from a unique perspective of information exchange levels, which are defined according to the key steps of an ML process, i.e., we consider the following levels: 1) the level of preprocessed data; 2) the level of learning models; 3) the level of extracted knowledge; and 4) the level of intermediate results. We explore and analyze the potential of threats for each information exchange level based on an overview of current state-of-the-art attack mechanisms and then discuss the possible defense methods against such threats. Finally, we complete the survey by providing an outlook on the challenges and possible directions for future research in this critical area.

In the real world, road networks with weight and label on edges can be applied in several application domains. The shortest path query with label restrictions has been receiving increasing attention recently. To efficiently answer such kind of queries, a novel index, namely Contraction Hierarchies with Label Restrictions (CHLR), is proposed in the literature. However, existing studies mainly focus on the static road networks and do not support the CHLR maintenance when the road networks are dynamically changed. Motivated by this, in this paper, we investigate the CHLR maintenance problem in dynamic road networks. We first devise a baseline approach to update CHLR by recomputing the potential affected shortcuts. However, many shortcuts recomputed in baseline do not change in fact, which leads to unnecessary overhead of the baseline. To overcome the drawbacks of baseline, we further propose a novel CHLR maintenance algorithm which can only travel little shortcuts through an update propagate chain with accuracy guarantee. Moreover, an optimization strategy is presented to further improve the efficiency of index maintenance. Considering the frequency of edge changes, we also propose a batch index maintenance algorithm to handle batch edge changes which can process a large number of edge changes at once. Furthermore, a parallel method is proposed to further accelerate calculations. Extensive and comprehensive experiments are conducted on real road networks. The experimental results demonstrate the efficiency and effectiveness of our proposed algorithms.

Repulsive and long-range exciton–exciton interactions are crucial for the exploration of one-dimensional (1D) correlated quantum phases in the solid state. However, the experimental realization of nanoscale confinement of a 1D dipolar exciton has thus far been limited. Here, we demonstrate atomically precise lateral heterojunctions based at transitional-metal dichalcogenides (TMDCs) as a platform for 1D dipolar excitons. The dynamics and transport of the interfacial charge transfer excitons in a type II WSe2–WS1.16Se0.84lateral heterostructure were spatially and temporally imaged using ultrafast transient reflection microscopy. The expansion of the exciton cloud driven by dipolar repulsion was found to be strongly density dependent and highly anisotropic. The interaction strength between the 1D excitons was determined to be ∼3.9 × 10–14eV cm–2, corresponding to a dipolar length of 310 nm, which is a factor of 2–3 larger than the interlayer excitons at two-dimensional van der Waals vertical interfaces. These results suggest 1D dipolar excitons with large static in-plane dipole moments in lateral TMDC heterojunctions as an exciting system for investigating quantum many-body physics.

Transition metal dichalcogenide heterostructures provide a versatile platform to explore electronic and excitonic phases. As the excitation density exceeds the critical Mott density, interlayer excitons are ionized into an electron–hole plasma phase. The transport of the highly non-equilibrium plasma is relevant for high-power optoelectronic devices but has not been carefully investigated previously. Here, we employ spatially resolved pump–probe microscopy to investigate the spatial-temporal dynamics of interlayer excitons and hot-plasma phase in a MoSe2/WSe2twisted bilayer. At the excitation density of ∼1014cm–2, well exceeding the Mott density, we find a surprisingly rapid initial expansion of hot plasma to a few microns away from the excitation source within ∼0.2 ps. Microscopic theory reveals that this rapid expansion is mainly driven by Fermi pressure and Coulomb repulsion, while the hot carrier effect has only a minor effect in the plasma phase.

Mussel-inspired polydopamine (PDA) and its derivative materials have exhibited a huge potential as a facile and versatile route to fabricate multifunctional coatings on virtually any substrate surface. However, their performance and applicability are frequently obstructed by limited optical absorption in visible regions of PDA and poor surface adhesion persistence of dopamine solutions. Herein, we report a facile strategy to improve these problems by rationally regulating the dopamine polymerization pathway through mixed-solvent-mediated periodate oxidation of dopamine. The spectral analysis, ultrahigh-performance liquid chromatography coupled with high-resolution mass spectrometry, and density functional theory simulations systematically demonstrate that the mixed-solvent reaction systems can effectively accelerate the periodate-induced formation of cyclized moieties in the PDA microstructure and inhibit their further oxidative cleavage, thus contributing to narrowing the inherent energy band gap of PDA and improving the long-lasting surface deposition performance of aged dopamine solutions. Moreover, the newly constructed cyclized species-rich PDA coatings have excellent surface uniformity and significantly enhanced chemical stability. Benefiting from these fascinating properties, they have been further used for permanent dyeing of natural gray hair with remarkably improved blackening effect and excellent practicability, which exhibited their promising prospect in real-world applications.

Blue light-emittin g diodes (LEDs) are important components for perovskite electroluminescence applications, which still suffer from insufficient luminescence efficiency and poor stability. In Cl/Br mixed perovskite NCs, surficial defects cause severe light failure and ion migration, the in-depth mechanism of which is also not clear. To gain insights into these issues, we employ the ligand post-addition approach for mixed Cl/Br NCs by using octylammonium hydrobromide (OctBr) ligands, which effectively decrease surficial light loss and block ion migration pathways. The passivated CsPbCl1.5Br1.5NCs exhibit exceptional blue emission with 95% PLQY, and the electroluminescence spectra of LEDs are located at the initial positions at the initial states. The treated NC blue devices show a negligible color shift as the voltage increases, which proves that electric-field-driven ion migration is drastically suppressed. In addition, OctBr-treated CsPbCl1.5Br1.5and CsPbClBr2NC LEDs show high external quantum efficiencies of 2.42 and 3.05% for emission peaks at 456 and 480 nm, respectively. Our work identified the nature of NC surface defects and provided a surficial modification approach to develop high-performance and color-stable blue mixed-halide perovskite LEDs.

This study proposes a method for calculating the landing footprints of re-entry vehicles based on the three-dimensional acceleration profile. Unlike the traditional case in which the reference angle-of-attack profile is given in advance, here, the manoeuvrability of the vehicle is enhanced owing to the release of the constraints of the angle-of-attack profile. Compared with the traditional methods of generating landing footprints, this method is more challenging because it is necessary to adjust the angle-of-attack and the bank angle simultaneously to obtain all feasible trajectories. With the enhancement of manoeuvrability, the traditional landing footprints solving strategy with a fixed bank direction under the premise of a given angle-of-attack is expected to make the footprints of the result locally smaller. Therefore, a layered design based on a three-dimensional profile and lateral priority strategy is proposed to solve the problem. First, a lateral flight corridor considering various path constraints is constructed. Then, the boundary interpolation of the flight corridor is used to generate an initial lateral profile. The longitudinal profile corresponding to the lateral profile is analysed according to the coupling relationship between the longitudinal and lateral profiles, and the corresponding trajectory is then obtained by numerical integration. The tentative landing footprints can be obtained by traversing all feasible profiles in the lateral corridor. Finally, to solve the problem of inaccuracy in the solution of landing footprints, the core innovation of this study is the generation of multiple groups of different lateral flight corridors by adjusting the initial and terminal bank directions. By solving the tentative landing footprints under different flight corridors and merging them, highly accurate landing footprints were obtained. The proposed method is tested with the CAV-H model of Lockheed Martin, and the results are compared with those of traditional methods to verify its effectiveness and feasibility.

Background: Premature ovarian failure (POF) is a type of pathological aging, which seriously interferes with the fertility of affected women. Electroacupuncture (EA) may have a beneficial effect; however, its mechanism of action is unknown. The purpose of this study was to determine the effect of EA on ovarian function in ovarian granulosa cells (OGCs) in a cyclophosphamide (CTX)-induced mouse model of POF.Methods: Mice were divided into three groups: wild type (WT) group, CTX group and CTX + EA group. EA was administered under isoflurane anesthesia at CV4, ST36 and SP6 for 30 min every 2 days, 2–3 times per week for a total of 4 weeks. Effects of EA on ovarian weight and level of estrogen were examined. The mRNA and protein expression levels of cell cycle–associated proteins were detected and mRNA modifications were analyzed.Results: EA significantly increased ovarian weight and reduced the proportion of atretic follicles in mice with CTX-induced POF (p < 0.05). EA increased the level of estrogen in the peripheral blood of mice and inhibited the modification of total mRNA N4-acetylcytidine (ac4C). A significant increase in the expression of P16 and N-acetyltransferase 10 (NAT10) and a significant decrease in the expression of Cyclin D (CCND1) and cyclin-dependent kinase 6 (CDK6) were observed in the OGCs of POF mice (p<0.05). After EA, P16 and NAT10 expression was decreased, and CCND1 and CDK6 expression was increased. Finally, EA reduced the ac4C modification of P16 mRNA-specific sites in the OGCs of POF mice.Conclusion: This study demonstrated that EA promoted the repair of the ovarian microenvironment by inhibiting the ac4C modification of P16 mRNA to decrease its stability and expression intensity, and by altering the activity of the P16/CDK6/CCND1 axis in OGCs.

$k$k-truss model is a typical cohesive subgraph model and has been received considerable attention recently. However, the $k$k-truss model only considers the direct common neighbors of an edge, which restricts its ability to reveal fine-grained structure information of the graph. Motivated by this, in this paper, we propose a new model named $(k, \tau)$(k,τ)-truss that considers the higher-order neighborhood ($\tau$τ hop) information of an edge. Based on the $(k, \tau)$(k,τ)-truss model, we study the higher-order truss decomposition problem which computes the $(k, \tau)$(k,τ)-trusses for all possible $k$k values regarding a given $\tau$τ. Higher-order truss decomposition can be used in the applications such as community detection and search, hierarchical structure analysis, and graph visualization. To address this problem, we first propose a bottom-up decomposition paradigm in the increasing order of $k$k values to compute the corresponding $(k, \tau)$(k,τ)-truss. Based on the bottom-up decomposition paradigm, we further devise three optimization strategies to reduce the unnecessary computation. We evaluate our proposed algorithms on real datasets and synthetic datasets, the experimental results demonstrate the efficiency, effectiveness and scalability of our proposed algorithms.

With the great amount of available data, especially collecting from the ubiquitous Internet of Things (IoT), the issue of privacy leakage arises increasingly concerns recently. To preserve the privacy of IoT datasets, traditional methods usually calibrate random noises on the data values to achieve differential privacy (DP). However, the amount of the calibrating noises should be carefully designed and a heedless value will definitely degrade the availability of datasets. Thus, in this work, we propose a stochastic perturbation method to sanitize the dataset, where the perturbation is obtained from the rest samples in the same dataset. In addition, we derive the expression of the utility level based on its unique framework and prove that the proposed algorithm can achieve the $\epsilon$ε-DP. To show the effectiveness of the proposed algorithm, we conduct extensive experiments on real-life datasets by various functions, such as query answers and machine learning tasks. By comparing with the state-of-the-art methods, our proposed algorithm can achieve a better performance under the same privacy level.

The decomposition family of a family of graphs often helps us to determine the error term in the well-known Erdős–Stone–Simonovits theorem. We study the Turán number of families of nonbipartite graphs such that their decomposition families contain a matching and a star. To be precisely, we prove tight bounds on the Turán number of such families of graphs. Moreover, we find a graph which is a counterexample to an old conjecture of Erdős and Simonovits, while all previous counterexamples are families of graphs.

We propose a design of an open resonator antenna to fulfill the requirements of high gain and low cost at 0.1 THz. A planar cavity with a loaded phase-shifting periodic structure is used to imitate a spherical cavity, which helps to support higher order modes and, hence, widen the bandwidth. The design procedure is introduced in detail. With the help of high-precision three-dimensional printing technology, the periodic structure can be manufactured with a relatively lower cost and complexity. Measurements were carried out to prove that the proposed antenna can achieve a 3 dB gain bandwidth of 13% and a peak gain over 16.8 dBi.

In the field of aviation, the contrate gear is an important component, the material of the contrate gear is the basis for ensuring the reliability and high performance of the aircraft engine, the commonly used material for contrate gear is 20Cr2Ni4A. In order to fully understand the electrolytic machining of the toothed groove of the contrate gear, a multiphysics coupling model of the electric field, the gas-liquid two-phase flow field and the temperature field was established to study the distribution of bubble rate, temperature, conductivity and current density in the processing gap. Simulation results show that the temperature and bubble rate gradually increase along the process direction in the processing gap, the conductivity and current density of the electrolyte gradually decrease.

Two-dimensional transition-metal dichalcogenides (TMDs) are promising as efficient and earth-abundant electrocatalysts for the hydrogen evolution reaction (HER). However, only the edge and defect sites show HER catalytic properties, while the basal plane, which has nonexistent unsaturated sites, is inactive. Herein, we tackle the key challenge of increasing the number of electrocatalytic sites by using a general and facile method for the effective layer-by-layer exfoliation of TMDs in water by using an amino acid, histidine (His), for the scalable production of single-layer TMDs nanosheets, which cannot be achieved using other common amino acids. Besides serving as an effective exfoliating agent, the N of Hiscan also serve as a doping agent to modulate the phase of single-layer TMDs nanosheets for greatly improving their electrocatalytic performance. The exfoliated single-layer MoSe2nanosheets were doped with high surface/bulk ratio Pt nanoparticles (PtNPs) to form MoSe2/PtNPs composites. Detailed electrochemical characterization shows that the MoSe2/PtNPs composite (0.45 at % Pt) exhibited an excellent HER performance with an ultralow overpotential of 198 mV (@100 mA cm–2), a Tafel slope of 24 mV/dec, and long-term electrochemical durability.

The discoveries of Cambrian Lagerstatten, which preserves mineralizing, as well as nonmineralizing organisms has recently reported a new species of the Cambrain arthropod Skania, which has a close resemblance to the organism Parvancornia and hence establishes a Precambrian root for arthropods. The various results and evidences obtained from their comparative study sets up a new calibration point to estimate the divergence time for the last ancestor of arthropods and priapulids on the basis of molecular clock methods.

The development of quantitative models for prediction of drug pharmacokinetics based on in vitro data has transformed early drug discovery. Drug unbound fraction (ƒu) characterization is a key consideration in pharmacokinetic and pharmacodynamic (PK/PD) modeling, assuming only unbound drug can interact with the target, and therefore has direct implications in the efficacy and potential toxicity of the drug. The current study describes the implementation of a hybridization liquid chromatography–tandem mass spectrometry (LC-MS/MS) platform for the direct quantitation of antisense oligonucleotide (ASO) ƒu. The method provides substantial improvements, including minimal matrix effects and high specificity when compared with previously used oligonucleotide ƒudetection methods such as ligand binding assays or liquid scintillation. The hybridization LC-MS/MS platform was integrated with ultracentrifugation, ultrafiltration, and equilibrium dialysis, and method performance for each technique was evaluated. Although ASO protein binding has been previously characterized in plasma, there were no studies that quantitated ASO ƒuin brain or cerebral spinal fluid (CSF). As ASOs continue to undergo clinical trials for neurologic and neuromuscular indications, ƒucharacterization in brain and CSF can provide invaluable information about ASO distribution and target engagement in the central nervous system, therefore providing support for in vivo PK/PD data characterization.SIGNIFICANCE STATEMENTA novel hybridization LC-MS/MS-based approach was successfully developed for the determination of ASO in vitro protein binding in plasma, and for the first time brain and CSF. Ultrafiltration, equilibrium dialysis, and ultracentrifugation were assessed for the separation of unbound ASO from biological matrices. The hybridization LC-MS/MS platform provided unique advantages, including minimal matrix effects and high specificity, compared with traditional ligand binding assays or liquid scintillation approaches, which enabled efficient and reliable in vitro protein binding assay.

Stem cell therapy is widely regarded as a promising strategy in regenerative medicine, yet the therapeutic effects of stem cells in vivo are limited by many factors when applied without additional factors, such as poor cell engraftment, uncontrolled differentiation, and unclear cell fates and niches. The emergence of nanotechnology has provided several solutions for these problems. Nanomaterial-based cell labeling and tracking have been extensively investigated in recent decades, and many innovative and multifunctional nanomaterials have been used to reveal the fate of stem cells, allowing more efficient, sensitive, and accurate imaging/tracking strategies for stem cells to be achieved. Nanomaterials enhance stem cell therapy by incorporating or integrating with stem cells and, as scaffolds or substrates, nanomaterials with antioxidant properties that can be used as graft coatings show great promise for clinical transformation. However, current reviews on the subject tend to focus on the various effects of nanomaterials on stem cells and are less concerned with their application to stem cell therapy. Accordingly, we herein present a review of progress in the application of nanomaterials in stem cell therapy over the last three years, which we hope will be of benefit to a comprehensive understanding of nanomaterial-mediated stem cell therapy from lab to pre-clinical practice.

Recent advances in emerging atomically thin transition metal dichalcogenide semiconductors with strong light–matter interactions and tunable optical properties provide novel approaches for realizing new material functionalities. Coupling two-dimensional semiconductors with all-dielectric resonant nanostructures represents an especially attractive opportunity for manipulating optical properties in both the near-field and far-field regimes. Here, by integrating single-layer WSe2and titanium oxide (TiO2) dielectric metasurfaces with toroidal resonances, we realized robust exciton emission enhancement over 1 order of magnitude at both room and low temperatures. Furthermore, we could control exciton dynamics and annihilation by using temperature to tailor the spectral overlap of excitonic and toroidal resonances, allowing us to selectively enhance the Purcell effect. Our results provide rich physical insight into the strong light–matter interactions in single-layer TMDs coupled with toroidal dielectric metasurfaces, with important implications for optoelectronics and photonics applications.

The bonding quality of bronze/steel bimetallic laminated composite is the key factor to whether it can be used in poor working conditions. In this study, bimetallic billets were prepared by the protective atmosphere casting process. The microstructural characteristics, mechanical properties and interface bonding mechanism of the bronze/steel bimetallic composites were analyzed comprehensively through a series of microstructure analysis (inicluding OM, SEM, and EDS) and mechanical properties tests. The experimental results demonstrate that the vaporization of lead (Pb) element in the bronze is only 0.4% in weight, and alloy elements are diffused into both sides at the interface. Moreover, the hardness in the bronze region exceeds 100.0 HV which indicates excellent wear resistance. Tensile and shear tests indicate that the fractures mainly occur on the bronze side with the interaction of the brittle fracture of Pb particles and the ductile fracture of Cu-Sn solid solution. The maximum tensile strength and shear strength reach 204.0 MPa and 211.0 MPa, respectively. These results demonstrate that the protective atmosphere casting process is applicable for the preparation of bronze/steel bimetallic laminated composite with high quality.

In order to respond to nuclear or radiological emergencies effectively and protect the physical and mental health of the public, the national-, provincial-, municipal- and county-level public health response systems for nuclear or radiological emergencies had been established in China by the end of twentieth century. The health administrative departments at all levels have established professional emergency response teams, continue to improve their own level of emergency response systems and operating mechanisms, enhance the capabilities of radiation injury treatment, radiation monitoring and protection through training and exercises and also pay attention to the logistical support for emergency response. In this article the organizations, management system and capabilities of public health response to nuclear or radiological emergencies in China are briefly introduced. We try to strengthen information exchange and cooperation with foreign counterparts in this field in the future, so as to jointly promote the development of preparedness and response for nuclear or radiological emergencies.

Owing to the advantages of high energy density, low cost, abundant sulfur reserves and environmentally friendly nature, lithium-sulfur batteries (LSBs) were considered as one of the potential candidates of energy storage devices for the next generation. However, the significant challenges in this area stem from the sluggish reaction kinetics of the insoluble Li2S product and the capacity degradation triggered by the severe shuttle effect of polysulfides. It has been firmly established through numerous studies that modifying separators is an effective approach to enhance the properties of LSBs by facilitating the catalytic kinetic conversion and chemical adsorption of lithium polysulfides (LiPSs). In this work, we report a straightforward method for fabrication of the phosphorus doped porous CeO2(P-CeO2) as separator modifier to accelerate the catalytic kinetic conversion of polysulfides and effectively inhibit the shuttle effect in LSBs. Through coin batteries tests, P-CeO2modified PP separator (P-CeO2//PP) exhibits remarkable electrochemical performance. It demonstrates a high initial capacity of 1180 mAh/g at 0.5 C, surpassing the performance of the bare CeO2//PP separator. Furthermore, the P-CeO2//PP separator demonstrates enhanced cycling stability, with a low-capacity fading rate of only 0.048% per cycle over 1000 cycles at 2 C. In compared with bare CeO2//PP, P-CeO2//PP exhibits high redox peak current, enhanced adsorption property of Li2S6and early Li2S precipitation. These results highlight the superior performance of the P-CeO2//PP separator compared to the bare CeO2//PP separator. Hence, this research presents a successful strategy for the modification of LIBs separator with improved electrochemical performance and cycle stability.

•Subclones derived from CT26 cells showed different responses to anti-PD-1 antibody treatment, suggesting that the heterogeneity of CRC may affect the efficacy of anti-PD-1 antibody treatment.•SCC2 group exhibited significant infiltration of T cells within the tumor tissue than the other groups in vivo. However, SCC2 showed resistant to anti-PD-1 therapy, which suggests that other factors may contribute to SCC2 resistance to anti-PD-1 therapy.•Compared with SCC1 and CT26 tumors, SCC2 tumors showed increased expression of GC-related genes (Hsd11b1, Sgk3, Il7r, Tgfbr2). Anti-PD-1 treated SCC2 tumors showed reduced expression of GC-associated genes (Hsd11b1, Il7r). These results suggest that the resistance of SCC2 resistance to anti-PD-1 therapy was associated with elevated expression of genes related to GCs.•No previous studies have been found on the association between SCC2 resistant to anti-PD-1 therapy and the elevated genes associated with glucocorticoids.

The electrochromic devices explored in this study show tremendous promise for energy conservation, enabling active, adaptive control of solar heat and lighting in buildings. However, a majority of existing devices fail to perform optimally in areas with significant temperature fluctuations. Addressing this challenge, we introduce a new aprotic polar electrolyte (APE) for use in a reversible silver deposition electrochromic device. This novel device boasts an impressive ability to switch from a highly transparent state (with light transmittance at 650 nm being equal to or greater than 80%) to a reflective mirror-like state (with light transmittance at 650 nm being equal to or less than 1%) across an extensive temperature range spanning from −40 to 40 °C. The device’s switching threshold decreases with lower temperatures, moving from −1.97 V at 40 °C to −2.37 V at −40 °C. The coloration process completes in as swift as 3.5 s at 40 °C and in 13.6 s at −40 °C, while the bleaching process requires 16.3 s at 40 °C and extends to 71.0 s at −40 °C. Achieving high optical contrast (with a ΔT= 80% at 650 nm) at varied temperatures, the device also demonstrates exceptional durability across numerous cycles.

Inorganic thermochromic materials exhibit a tunable color gamut and a wide chromatic temperature range, indicating their potential for intelligent adaptive applications in thermal warning, temperature indication, thermal regulation, and interactive light-to-thermal energy conversion. However, most metal-oxide-based thermochromic materials show weak chromaticity adaption with the change of temperature, which needs further understanding of the microscopic principle to clarify the potential route to improve the contrast and identifiability for fabricating better thermochromic materials. Using perovskite-structure (AMO3) alkaline earth metal stannate (Ba1–xSrxSnO3, 0.0 ≤ x≤ 1.0) as a model system, this paper reports for the first time the mechanism of the properties of thermally induced defect-enhanced charge transfer-type (CTT) thermochromic materials and the strategy for regulating their thermochromic properties by A-site cations. BaSnO3exhibits continuously reversible thermochromic properties with high contrast from weak light yellow (b* = 11) to strong bright yellow (b* = 58) between room temperature and 550 °C. In-situ high-temperature X-ray diffraction (in-situ XRD), in-situ UV–vis absorption spectroscopy (in-situ UV–vis), thermogravimetric (TG), and electron paramagnetic resonance (EPR) spectra indicate that this excellent thermochromic phenomenon is attributed to the weakening of Sn–O bond hybridization at high temperatures, as well as the formation of a large number of oxygen vacancies at the top of the valence band, and the enhanced charge transfer resulting from the generation of impurity levels in the Sn2+5s2intermediate. Replacing Ba2+by Sr2+in Ba1–xSrxSnO3successfully tuned the thermochromic properties, which is attributed to the Sr2+doping level-directed oxygen defect concentration and deoxygenation rate. The demonstrated defect-enhanced charge transfer behavior promotes a feasible route for lattice oxygen-mediated thermochromic materials and provides a fundamental relationship between thermally induced defects and colorimetry.

Symbiotic nitrogen fixation (SNF) facilitated by the interaction between legumes and rhizobia is a well-documented and eco-friendly alternative to chemical nitrogen fertilizers. Host plants obtain fixed nitrogen from rhizobia by providing carbon and mineral nutrients. These mineral nutrients, which are mostly in the form of metal ions, are implicated in various stages of the SNF process. This review describes the functional roles played by metal ions in nodule formation and nitrogen fixation and specifically addresses their transport mechanisms and associated transporters within root nodules. Future research directions and potential strategies for enhancing SNF efficiency are also discussed.

Thermochromism is a color change phenomenon for a compound when it undergoes a heating/cooling process. The observation of this phenomenon mostly relies on the naked eye, rather than an exact optical technique, which retards better new thermochromic material design and is detrimental to the understanding of its fundamental mechanism. In this paper, we present a facile and noninvasive in situ ellipsometric method to monitor the optical properties evolution of CsPbI3film in its thermochromic process with three notable phase transitions from room temperature to 340 °C. We monitored the in situ structure evolution of CsPbI3film by three techniques, namely, temperature-dependent X-ray diffraction, Raman spectroscopy, and spectroscopic ellipsometry. Four phases of CsPbI3, that is, α, β, γ, and δ, could be detected in temperature-dependent spectroscopic ellipsometry measurement. Especially, we found the most expected “stable” α and γ phases show temperature-dependent bandgap evolution even in their phase-stable temperature region. The in situ spectroscopic ellipsometry therefore could function as a facile and noninvasive technique for detection of phase and band evolution with potential applications in smart windows, semiconductor, and optical devices.

Objective Our study was performed to investigate whether micro-223 promotes diabetic Osteoarthritis (OA) progression by regulating cartilage degeneration and subchondral bone remodeling.Methods The expression of miR-223 in human normal cartilage, OA cartilage, and subchondral bone tissue with or without DM was detected by real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR). miR-223 mimic or inhibitor was transfected into chondrocytes. Cell viability and apoptosis were assessed by 3-(4,5)-dimethylthiahiazo(-2)-3,5-diphenyltetrazolium bromide (MTT) and Terminal Deoxynucleotidyl Transferase(TdT)-mediated dUTP nick end labeling (TUNEL) assay, respectively.Results miR-223 was significantly higher in human diabetic OA cartilage and subchondral bone compared with normal OA and healthy control. Overexpression of miR-223 accelerated cartilage degeneration and subchondral bone sclerosis in diabetic OA mice, whereas miR-223 inhibition had the opposite effect. In vitroupregulation of miR-223 decreased proliferation and enhanced apoptosis of chondrocytes. Meanwhile, downregulation of miR-223 promoted glycosaminoglycan (GAG) production in chondrocytes.Conclusion miR-223 promotes diabetic OA progression by regulating cartilage degeneration and subchondral bone remodeling both in vitroand in vivo.

Colin James Oliver Harrison was a well-known ornithologist, who was remembered for his various contributions into understanding different aspects of bird behavior and to rejuvenate interest in the study of avian fossils. He was a very intelligent, generous and social man and did a great job by finding out the origin of the Recent Palaearctic bird species and by presenting his great works in the form of several books.

The present study investigated how mild moxibustion treatment affects the intestinal microbiome and expression of NLRP3-related immune factors in a rat model of intestinal mucositis (IM) induced with 5-fluorouracil (5-Fu).

The brown planthopper (BPH), Nilaparvata lugens,an important rice insect pest, can enhance its virulence to BPH-resistant rice within as short a span as several generations. Here, we cloned a pancreatic triglyceride lipase (PTL) gene (NlPTL) in N. lugens,and found that its mRNA level was higher in the high virulence population (fed on variety Rathu Heenati, P-RH) than in the low virulence population (fed on variety Taichung Native 1, P-TN1). Knocking down NlPTLcaused BPH individuals to spend more time in non-penetration and the pathway phases and less time feeding on the phloem of rice plants; these changes consequently decreased food intake, lipid content, survival rate, and fecundity in the insects. These findings reveal for the first time that PTL in BPH is involved in its virulence to rice plants.

The nanoscale periodic potentials introduced by moiré patterns in semiconducting van der Waals heterostructures have emerged as a platform for designing exciton superlattices. However, our understanding of the motion of excitons in moiré potentials is still limited. Here we investigated interlayer exciton dynamics and transport in WS2–WSe2heterobilayers in time, space and momentum domains using transient absorption microscopy combined with first-principles calculations. We found that the exciton motion is modulated by twist-angle-dependent moiré potentials around 100 meV and deviates from normal diffusion due to the interplay between the moiré potentials and strong exciton–exciton interactions. Our experimental results verified the theoretical prediction of energetically favourable K–Q interlayer excitons and showed exciton-population dynamics that are controlled by the twist-angle-dependent energy difference between the K–Q and K–K excitons. These results form a basis to investigate exciton and spin transport in van der Waals heterostructures, with implications for the design of quantum communication devices.

. Electrochemical etching is widely used to process refractory metals such as tungsten and molybdenum. Flow field is one of the crucial factors that influence the surface quality in electrochemical etching. In this paper, the electrochemical etching flow field was analyzed via FLUENT, the characteristics of flow field in electrochemical etching are studied, furthermore, the effects of four different outlet forms of electrolyte on flow field uniformity, electrolyte velocity and pressure distribution are investigated. Under the same electrolyte flow rate, the flow field characteristics of different outlet forms are analyzed by velocity vector diagram, pressure distribution nephogram, velocity and pressure curve diagram. The simulation results indicate that stable electrolyte velocity and uniform pressure distribution of flow field are obtained when the outlet form of electrolyte adopts the optimized flat. Finally, the fixture for this outlet form is designed and fabricated, and experimental verification is carried out, which shown that the flow field is uniform and the crystal plane of the workpiece is well-distributed which according with the process requirements.

In this communication, we report two feasible routes to controllably synthesize Bi-based perovskite structure superconductor crystals with tunable shapes that expose well-defined crystal facets. The shape of as-synthesized crystals is determined by the relative growing speed along <001> and <111> crystallographic directions that correlate to the ratio of the propagation tendency of the A-O layer to BiO6octahedral units. We have found two routes to control this process by either decreasing the growing speed of the A-O layer (NH4+route) or increasing that of the BO6octahedral units (Bi(V)/Bi(III) route). The crystal growth and shape formation mechanism were analyzed based on the E–pH diagrams and crystal structure characteristics according to thermodynamic data of the Bi–Ba–K–Na–H2O system and the Bravais–Friedel–Donnay–Harker (BFDH) theory. The temperature-dependent magnetization measurement indicates that the diamagnetic and superconductive performance of the samples is determined by the crystal shape and their exposed facets. Truncated cubic shape crystals show the highest transition temperature (∼30 K), while cubic shape crystals show the largest shielding volume fraction (up to 49.2%). The increasing exposed ratio of {111} facets on the surface of crystals reduces the shielding volume fraction.

A photonic crystal fiber based on a surface plasmon resonance sensor coated with segmented silver-titanium dioxide (${\rm Ag} \text{-} {{\rm TiO}_2}$Ag-TiO_2) film is proposed for microfluid refractive index sensing. The sensing properties of the designed sensor are analyzed numerically by the full-vectorial finite element method. The results display that the wavelength sensitivity can be tuned by the thickness of the ${{\rm TiO}_2}$TiO_2 film and segmented number and angle of the ${\rm Ag} \text{-} {{\rm TiO}_2}$Ag-TiO_2 film. It is observed that an average sensitivity of 6329 nm/RIU for refractive indexes ranging from 1.330 to 1.360, and a maximum wavelength sensitivity of 10600 nm/RIU with a high wavelength resolution of ${9.43} \times {{10}^{ - 6}}\;{\rm RIU}$9.43×10^−6RIU, can be achieved in the sensing range of 1.350 to 1.355. In addition, it also shows a maximum amplitude sensitivity of ${633.4001}\;{{\rm RIU}^{ - 1}}$633.4001RIU^−1, and the maximum figure of merit is 303 with ${n_a}$n_a varying from 1.330 to 1.360, which can be applied to the field of chemical and biological analysis.

A novel metal preloading route is proposed to prepare Pt/SAPO-11 bifunctional catalysts. The addition of platinum brings about an increase in catalyst product yield with a growth rate of 87% attributed to chemical adsorption between Pt and the lone pair of electrons in the nitrogen atom of the structure-directing agent. More interestingly, it can be concluded from the HAADF-STEM, SE-STEM images and DRIFTS data on CO adsorption, there are small Pt nanoparticles confined inside the SAPO-11 molecular sieve, while the big Pt nanoparticles are dispersed on the surface. The synergistic effect between the metal sites and acid sites can be improved by the enhancement of metal–acid balance, by adjusting the nPt/nAratio. A better metal–acid balance property is achieved and the carbenium ion can quickly go through the hydrogenating reaction on Pt nanoparticles, hence shortening the time it is trapped in the acid sites upon n-dodecane hydroisomerization. Consequently, the cracking reaction can be effectively avoided and liquid yield as high as 99% and isomer yield up to 84% is produced, much superior than the Pt/SAPO-11 catalyst synthesized viathe traditional impregnation method of Pt with the maximum isomer yield of 52%. Moreover, more multi-branched isomers are produced and can further help improve the low-temperature rheology when used as lubricant base oil.

Separating the active units while maintaining the majority of the functions of enzymes seems to be a paradox and therefore challenging, not to mention also improving the adaptability to harsh conditions simultaneously. In this paper, we demonstrate that a well-designed hexapeptide molecule, deuterohemin-β-Ala-His-Thr-Val-Glu-Lys (DhHP-6), adapted from cytochrome c, shows superior peroxidase activity over a wide pH and temperature range. The activity of DhHP-6 was first assessed viathree substrates (i.e., 2,2′azinodi(3-ethylbenzthiazoline)-6-sulfonate (ABTS), 1,2,3-trihydroxybenzene (THB) and phenol) with reference to the classically studied examples microperoxidase (MP-11) and horseradish peroxidase (HRP). The environmental adaptability was assessed viathree factors: pH, temperature, and the polarity of solvents. In the phenol substrate model reaction, DhHP-6 shows superior specific activity (749.73 U mg−1) and adaptability compared to HRP (311.32 U mg−1). Under the optimum solvent conditions (15% methanol by volume ratio), the enzymatic efficiency (Vm/Km) of DhHP-6 reached 27.9 × 10−3s−1, 16-times higher than that of HRP (1.81 × 10−3s−1). The methanol concentration dependent electron paramagnetic spectra show an axial-promoted intermediate process for the phenol catalytic reaction. This work provides a protocol and feasible methodology for the design and fabrication of natural enzyme mimicking small molecules that maintain most of their native activity for better biocatalytic applications in organic pollutant remediation and other related processes.

The synthesis of intermetallic antimonides usually depends on either the high-temperature alloying technique from high-purity metals or the flux method in highly poisonous Pb-melt. In this paper, we introduced a soft-chemical method to synthesize intermetallic antimonides from ternary chalcogenide precursors under an argon atmosphere below 200 °C. Powder X-ray diffraction and compositional analysis clearly indicate that a new phase of the Ag3Sb nanocrystal was synthesized from the Ag3SbS3precursors. Three types of trialkylphosphines (TAPs) were applied as desulfurization agents, and the transformation mechanism was elucidated. The capability of the desulfurization agent follows the sequence of triphenylphosphine (TPP) > tributylphosphine (TBP) > trioctylphosphine (TOP). Besides, this TAP-driven desulfurization route to synthesize the intermetallic phase could also be possible for AgSbSe2and Sb2S3. Therefore, this paper provides an efficient and mild technique for the fabrication of intermetallic nanocrystals.

Superlattices in crystals, particularly in perovskite oxides with strong correlation effects, can create new states of matter and produce peculiar physicochemical phenomena. However, the newfangled perovskite superlattices depend on physical deposition with unit-cell precision. It has been challenging to explore a new suitable chemical method to tailor perovskite superlattices. Herein, we present a new bottom-up strategy to precisely prepare atomic-scale oxide superlattices of (LaMnO3)1-(La1-x-yCaxKyMnO3)2in a monodispersed perovskite La0.66Ca0.29K0.05MnO3(LCKMO). The special atomic-scale perovskite superlattices are demonstrated using SAED, HAADF-STEM, XRD, and atomic-resolution elemental mapping. Our experiments reveal that the perovskite superlattices can be fabricated under extreme hydrothermal conditions utilizing ultra-high concentrations of KOH. An approximate molten salt system in the hydrothermal process can induce the disproportionation reaction of MnO2solids, which is vital to the growth of ordered perovskite superlattices. This work not only clarifies the hydrothermal growth process of perovskite oxides in extreme conditions, but also proposes a novel engineering route toward perovskite superlattices.

Purpose: Early evaluation of the efficacy of first-line chemotherapy combined with bevacizumab in patients with colorectal cancer liver metastasis (CRLM) remains challenging. This study used 2-month post-chemotherapy spectral computed tomography (CT) to predict the overall survival (OS) and response of CRLM patients with bevacizumab-containing therapy. Method: This retrospective analysis was performed in 104 patients with pathologically confirmed CRLM between April 2017 and October 2021. Patients were treated with 5-fluorouracil, leucovorin, oxaliplatin or irinotecan with bevacizumab. Portal venous phase spectral CT was performed on the target liver lesion within 2 months of commencing chemotherapy to demonstrate the iodine concentration (IoD) of the target liver lesion. The patients were classified as responders (R +) or non-responders (R −) according to the Response Evaluation Criteria in Solid Tumors (RECIST) v1.1 at 6 months. Multivariate analysis was performed to determine the relationships of the spectral CT parameters, tumor markers, morphology of target lesions with OS and response. The differences in portal venous phase spectral CT parameters between the R + and R − groups were analyzed. Receiver operating characteristic (ROC) curves were used to evaluate the predictive power of spectral CT parameters. Results: Of the 104 patients (mean age ± standard deviation: 57.73 years ± 12.56; 60 men) evaluated, 28 (26.9%) were classified as R + . Cox multivariate analysis identified the iodine concentration (hazard ratio [HR]: 1.238; 95% confidence interval [95% CI]: 1.089–1.408; P&lt; 0.001), baseline tumor longest diameter (BLD) (HR: 1.022; 95% CI: 1.005–1.038, P= 0.010), higher baseline CEA (HR: 1.670; 95% CI: 1.016–2.745, P= 0.043), K-RAS mutation (HR: 2.027; 95% CI: 1.192–3.449; P= 0.009), and metachronous liver metastasis (HR: 1.877; 95% CI: 1.179–2.988; P= 0.008) as independent risk factors for patient OS. Logistic multivariate analysis identified the IoD (Odds Ratio [OR]: 2.243; 95% CI: 1.405–4.098; P= 0.002) and clinical N stage of the primary tumor (OR: 4.998; 95% CI: 1.210–25.345; P= 0.035) as independent predictor of R + . Using IoD cutoff values of 4.75 (100ug/cm3) the area under the ROC curve was 0.916, sensitivity and specificity were 80.3% and 96.4%, respectively. Conclusions: Spectral CT IoD can predict the OS and response of patients with CRLM after 2 months of treatment with bevacizumab-containing therapy.