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Chemical modification of diamond surfaces generates a negative electron affinity (NEA), which shows great potential in realizing electron emission. In this study, zirconium (Zr) termination on clean and oxidized diamond (100) surfaces is theoretically proposed by using the structure prediction method, and electronic properties of these predicted surfaces are investigated by first-principles calculations. On the oxidized surfaces, the adsorption energy at 0.25 monolayer (ML) Zr coverage reaches a high value of −10.42 eV, further confirmed by the largest integrated crystal orbital Hamiltonian population value of 6.61 eV. For clean and oxidized diamond (100) surfaces, the largest NEA values at 0.25 ML Zr coverage are −3.75 eV and −3.45 eV, respectively. The dynamic stability of these surface structures is demonstrated by calculating phonon dispersion curves. Furthermore, ab initiomolecular dynamics simulations confirm the high thermal stability of the oxidized diamond surface. Therefore, these results indicate that Zr-terminated diamond (100) surfaces possess good thermal stability and higher NEA, making them promising candidate materials for electron emission applications.

The high corrosion sensitivity and the potential bio-toxicity of Mg–Ag alloys limit their wide applications for the production of implanted devices. In the present work, Mn is added into the Mg–Ag alloy to optimize its corrosion behaviour. The corrosion behaviour of Mg–Ag–Mn alloys is investigated with the underlying microstructural factors examined. The Mg–Ag alloy with 2 wt% Mn exhibits the highest corrosion resistance after post-casting heat treatment at 440 °C. The addition of Mn results in α-Mn phase with the incorporation of Fe, which suppresses the cathodic activity of impurity Fe. Further, heat treatment of the cast alloys homogenizes the distribution of Ag and promotes the precipitation of α-Mn phase. The former removes Ag segregations as potential cathodes; the latter promotes a more uniform distribution of cathodes and, therefore, prevents localized corrosion.

The occurrence of different forms of iron and manganese colloids in the subsurface environment has been widely reported. However, their sedimentation kinetics and stability mechanisms have been scarcely addressed. In this study, the effect of pH, electrolytes, and fulvic acid on the 24 h-scale sedimentation kinetics of iron and manganese colloids was investigated, and their mechanisms were described by the classic Derjaguin–Landau–Verwey–Overbeek (DLVO) and extended DLVO (XDLVO) theories. The results indicated that the colloidal sedimentation behavior was not only affected by their structures, but also by their hydrochemical environments. The sedimentation rate of these colloids increased with increasing pH. The electric double layer of colloids was compressed at a higher electrolyte concentration and valence state, further inducing colloidal sedimentation. However, fulvic acid could retard colloidal sedimentation as a result of electrostatic repulsion and a steric hindrance effect. The DLVO and XDLVO theory results suggest that both the total potential energy and the energy barrier decreased with increasing electrolyte concentration or valence state, whereas they increased with increasing fulvic acid concentration. Moreover, the repulsive potential was dominant for iron colloid sedimentation in Na+and Ca2+, whereas the sedimentation of manganese colloids was mainly controlled by the repulsive potential in Na+and the attractive potential in Ca2+. These findings provide a basic reference for understanding the fate and transport of iron and manganese colloids and associated contaminants in various subsurface environments.

Developing selective inhibitors for Janus kinase 1 (JAK1) is a significant focus for improving the efficacy and alleviating the adverse effects in treating immune–inflammatory diseases. Herein, we report the discovery of a series of C-5 pyrazole-modified pyrrolopyrimidine derivatives as JAK1-selective inhibitors. The potential hydrogen bond between the pyrazole group and E966 in JAK1 is the key point that enhances JAK1 selectivity. These compounds exhibit 10- to 20-fold JAK1 selectivity over JAK2 in enzyme assays. Compound 12balso exhibits excellent JAK1 selectivity in Ba/F3-TEL-JAK cellular assays. Metabolism studies and the results of the hair growth model in mice indicate that compound 12bmay be a viable lead compound for the development of highly JAK1-selective inhibitors for immune and inflammatory diseases.

Titanium dioxide (TiO2) recently has attracted a great deal of attention in different fields, such as renewable energy and pollutant removal, due to its low price and amphoteric nature. Many studies have pointed out that phase composition and oxygen vacancies play a certain role in promoting the performance of TiO2. However, the effect of oxygen vacancy on the phase transformation of TiO2has been ignored, which also influences the phase composition and limits its application under certain conditions. In this paper, by controlling the univariate of oxygen vacancy, the influence of oxygen vacancy on the stability and crystal type of TiO2is clearly pointed out, with the help of variable temperature in situ X-ray diffraction, differential thermal analysis (DTA), and discrete Fourier transform (DFT) theoretical calculations. The formation of oxygen vacancy can reduce the phase-change energy, which must be overcome before rearrangement of the structure, and promote the phase transformation of anatase. Based on these, it also provides a guide for the design of materials with oxygen vacancy.

Osimertinib, an orally administered third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, is widely approved for the first-line and second-line treatment of advanced non-small-cell lung cancer (NSCLC) with EGFRmutations. However, the rapid development of osimertinib resistance renders the unsustainable treatment benefit. Patients with EGFR-mutated NSCLC who develop osimertinib resistance, especially those acquiring relatively rare and ‘off-target’ resistance mutations, still lack effective therapeutic options for postosimertinib therapy. Herein, we reported a 73-year-old woman diagnosed with T1N3M1 lung adenocarcinoma harboring EGFRL858R mutation, who acquired two GNASmutations (R201C and R201H) and lost the EGFRL858R mutation after progression on icotinib and osimertinib. The patient was subsequently treated with trametinib and there was no obvious tumor increase. Our study revealed that GNASR201 can confer the osimertinib resistance in EGFR-positive NSCLC, and present the first report of the prevalence of GNASR201C and R201H mutants in NSCLC which response to trametinib treatment. Our case suggests that trametinib could be a treatment option in NSCLC patients harboring GNAS-activating mutations.

Predicting the dynamic mechanical characteristics of rocks during freeze–thaw cycles (FTC) is crucial for comprehending the damage process of FTC and averting disasters in rock engineering in cold climates. Nevertheless, the conventional mathematical regression approach has constraints in accurately forecasting the dynamic compressive strength (DCS) of rocks under these circumstances. Hence, this study presents an optimized approach by merging the Coati Optimization Algorithm (COA) with Random Forest (RF) to offer a reliable solution for nondestructive prediction of DCS of rocks in cold locations. Initially, a database of the DCS of rocks after a series of FTC was constructed, and these data were obtained by performing the Split Hopkinson Pressure Bar Test on rocks after FTC. The main influencing factors of the test can be summarized into 10, and PCA was employed to decrease the number of dimensions in the dataset, and the microtests were used to explain the mechanism of the main influencing factors. Additionally, the Backpropagation Neural Network and RF are used to construct the prediction model of DCS of rock, and six optimization techniques were employed for optimizing the hyperparameters of the model. Ultimately, the 12 hybrid prediction models underwent a thorough and unbiased evaluation utilizing a range of evaluation indicators. The outcomes of the research concluded that the COA-RF model is most recommended for application in engineering practice, and it achieved the highest score of 10 in the combined score of the training and testing phases, with the lowest RMSE(4.570,8.769), the lowest MAE(3.155,5.653), the lowest MAPE(0.028,0.050), the highest R2(0.983,0.94).

Due to the rarity of primary cervical lymphoma (PCL), the long-term survival of patients with cervical lymphoma and factors influencing survival are unknown. This study aimed to compare the survivals of patients with PCL and those with other cervical tumors and construct a clinical prediction model to assess the prognosis of patients with PCL. Patients with PCL from the Surveillance, Epidemiology, and End Results database were allocated randomly in a 7:3 ratio to the training and validation sets. Cox proportional hazard and Fine-Gray models were used to verify independent factors influencing overall survival (OS) and disease-specific survival (DSS), and nomograms were constructed. Receiver operating characteristic curve analysis and decision curve analysis (DCA) were used to test the performance and clinical utility of the models, respectively. We included 206 patients with PCL. The areas under the curves (AUCs) and DCA showed that all models had clinical benefits; The models constructed in this study had a predictive performance for patients with PCL. It can guide clinicians to rationalize the treatment plan for patients.

3,4-Dichloro-5-(6-chloro-9-(4-fluorobenzyl)-9H-purin-8-yl)isothiazole, a novel purine derivative, was synthesized by the cyclization of pyrimidine amine. Its structure was characterized by 1H NMR, 13C NMR, 19F NMR, H RMS and single-crystal X-ray diffraction. This compound 3is crystallized from a mixed solvent of dichloromethane and n-hexane (1:2, v/v) for structural identification as monoclinic crystal system, space group P21/nwith a =11.66250(10), b =8.21300(10), c =17.77920(10) Å, V =1676.34(3) Å3, Z= 4, Dc=1.643 g/cm3, F(000) = 832.0 and µ =6.301 mm−1. 22315 reflections were measured (8.43≤2θ≤58.10°), of which 3532 were unique (Rint= 0.0311) and used in all calculations. The final R =0.0334 (I> 2σ(I)) and wR =0.0842 (reflections). The title compound showed over 50% of growth inhibition against Botrytis cinereal, Cercospora arachidicola, Gibberella zeae, Rhizoctonia solaniand Sclerotinia sclerotiorumat 50 mg/L, and its EC50value against R. solaniwas 60.44 µmol/L, which was active at the same level as that of positive control diflumetorim with its EC50value of 60.29 µmol/L and less active than YZK-C22with its EC50value of 12.32 µmol/L, respectively. Our studies discovered that the combination of bioactive substructures of isothiazole with purine could be an effective way to novel fungicide development.

Target identification is one of the most important bases for novel pesticide development; pyruvate kinase (PK) was discovered as a potent fungicide target in our previous studies. To continue the PK-based fungicide development, novel isothiazole-purine derivatives were rationally designed and synthesized. Bioassay results showed that compound 5aidisplayed excellent in vitroactivity against Rhizoctonia solaniwith an EC50of 1.5 μg/mL, which was superior to those of positive controls diflumetorim with its EC50of 19.8 μg/mL and PK-based lead YZK-C22with its EC50of 4.2 μg/mL. Compounds 3b(5.2 μg/mL) and 3c(4.5 μg/mL) displayed better activities against Gibberella zeaewith their EC50s falling between 4.0 and 5.5 μg/mL, while YZK-C22showed an EC50of 6.4 μg/mL. In addition, 5ahexhibited promising in vivoactivity against Erysiphe graminisand Puccinia sorghiSchw. with 100% efficacy at 10 μg/mL and 90% efficacy at 2 μg/mL against P. sorghiSchw. Compound 5aishowed good PK inhibitory activity with an IC50of 38.8 μmol/L, and it was well docked into the active site of the target enzyme PK, which was slightly more active than YZK-C22with its IC50of 42.4 μmol/L. Our studies discovered that isothiazole-purines were PK-based fungicidal leads deserving of further study.

A method of modifying the surface of Cu current collector by adjusting polymer side chain to obtain excellent performance of lithium metal battery.

Natural products are one of the resources for discovering novel fungicidal leads. As a natural fungicide, osthole was used as a coumarin-based lead compound for the development of novel fungicides. Here, a series of 3,4-dichloroisothiazole-containing 7-hydroxycoumarins were rationally designed, synthesized, and characterized by introducing a bioactive substructure, 3,4-dichloroisothiazole, into the coumarin skeleton. In vitrobioassay indicated that compound 7gdisplayed good activity against Rhizoctonia solani, Physalospora piricola, Sclerotinia sclerotiorum, and Botrytis cinerea. Its median effective concentration (EC50) value against each of these fungi fell between 0.88 and 2.50 μg/mL, which was much lower than that of osthole against the corresponding pathogen (between 7.38 and 74.59 μg/mL). In vivoscreening validated that 7kexhibited 100%, 60%, and 20% efficacy against R. solaniKühn at 200, 100, and 50 μg/mL, respectively. RNA sequence analysis implied that growth inhibition of R. solaniby 7kmight result from potential disruptions of fungal membrane formation and intracellular metabolism. Furthermore, a field experiment with cucumber plants indicated that 7bshowed 62.73% and 74.03% efficacy against Pseudoperonospora cubensis(Berk. & Curt.) Rostov. at rates of 12.5 g a.i./ha and 25 g a.i./ha, respectively, which showed no significant difference between 7band osthole at 30 g a.i./ha. Our studies suggested that 7b, 7g, and 7kmight be used as fungicidal leads for further optimization.

Background:Since early December 2019, coronavirus disease 2019 (COVID-19) has emerged as a global pandemic and public health crisis. This study aims to explore the relationship between cardiac injury and inflammatory biomarkers in patients with severe COVID-19.Methods:We collected data on 91 patients with a confirmed diagnosis of severe COVID-19 from February 8 to March 31, 2020. Demographic characteristics, clinical data, and in-hospital outcomes were compared. The relationship between cardiac injury and inflammatory biomarkers was analyzed. Logistic regression was used to explore the independent risk factors for cardiac injury.Results:The mean age of all patients was 61 years±14 years. About half of the patients were male. Hypertension and coronary heart disease were more common in the cardiac injury group. The levels of inflammatory biomarkers in patients who experienced cardiac injury were generally higher than the levels of those without cardiac injury, including interleukin-6, interleukin-2 receptor (IL-2R), procalcitonin, and high-sensitivity C-reactive protein. There were positive correlations between the levels of high-sensitivity troponin I and N-terminal prohormone of brain natriuretic peptide and the levels of inflammatory biomarkers. Logistic regression shows that IL-2R (odds ratio 1.001, 95% confidence interval 1.000‐1.002, P=0.045) and comorbidities (odds ratio 4.909, 95% confidence interval 1.231‐19.579, P=0.024) are independent risk factors for cardiac injury in patients with severe COVID-19.Conclusion:High levels of inflammatory biomarkers are associated with higher risk of cardiac injury in patients with severe COVID-19. IL-2R and comorbidities are predictors of cardiac injury.

The wide application of Mg is hindered by its low corrosion resistance, especially for recycled Mg. In this work, a novel plasma electrolytic oxidation (PEO) process was conducted on a recycled Mg alloy with a high content of Al (~  2.3 wt%), which results in a polycrystalline PEO coating. The PEO coating displays a three-layered structure with a uniform elemental distribution. Unlike the outer layer decorated by channels of micrometre scales, the middle layer mainly contains submicron-sized pores associated with plasma discharges, whereas the fine pores originated from oxygen evolution were detected in the inner layer. The electrochemical measurements, hydrogen evolution tests and salt spray tests were conducted, indicating the superior corrosion resistance of PEO-coated recycled Mg alloy. Hence, the purposed PEO method could dramatically enhance the corrosion resistance of recycled Mg, which may broaden its application in the future.

In this work, we designed a LNA probe for the α-HL nanopore to simultaneously discriminate ctDNA and ncDNA with single-base difference. The LNA probe greatly improved the discrimination capability of single-base mismatch up to ˜12.3 times.

The capability of manipulating objects based on vision system are essential to robotic applications. For a vision system, high accuracy and robustness is vital. However, due to external environment and interference influences, as well as to lighting conditions influences, the most existing image-based vision system are limited in applications. In this context, a novel and robust data-driven vision system for recognizing different types of objects in various external situations has been presented in this paper. The system consists of three parts, namely, integrated module based on X2 Ultra-wideband (UWB) radar, deep learning (DL) module and robot controller. Specifically, the introduction of X2 UWB radar aims to (1) capture and process radar echo signals of different objects in various environments; (2) extract Range-Doppler power spectrograms from the processed signals accurately. The second part combines the DL algorithm to take the spectrograms as the input from the former to realize object classification. And the last part is used to control the behavior of the robot based on the classification results. The experimental results show that the proposed vision system achieves very reliable performance in recognizing six types of objects in four kinds of external environment and lighting conditions with three deep learning network models. Besides, by experimental data comparison, the performance of the proposed system achieves higher than that of the image-based system in the same poor conditions and ResNet is the optimal model for our proposed system in all conditions.

Identification of single-base mismatches has found wide applications in disease diagnosis, pharmacogenetics, and population genetics. However, there is still a great challenge in the simultaneous discrimination of single-base mismatch and full match. Combined with a nanopore electrochemical sensor, a shared-stem structure of molecular beacon was designed that did not need the labeling, but achieved an enhanced signal-to-background ratio of ∼104, high thermodynamic stability to bind with target sequences, and a fast hybridization rate. Fully matched and single-base mismatched sequences were simultaneously discriminated at the single-molecule level, which is expected to have potential applications ranging from the quick detection, early clinical diagnostics to point-of-care research.

A kind of L 2 -convergence theorems for the state dependent branching processes with continuous state and discrete time is studied and a group of sufficient conditions is obtained. [ABSTRACT FROM AUTHOR]

In recent years, Xingnan development zone have totally gone into high water cut stages and high recovery degree reserves from the partial period, facing with a stern fact that it transitions from a basic injected and produced fluid balance to a serious imbalance. Therefore, it is of important practical significance for predicting the production of remaining oil and improving recovery efficiency that strengthen the research of diminishing prediction of each well pattern. In this paper, by using a series means of graphical method, try and error method, curvilinear dislocation, type curve matching method and binary regression analysis, we comprehensively judged the production decline types of different well patterns, and calculate the production decline rate of each set of well pattern..

In this paper, an experimental research on the influence of the biomimetic surface morphology on the bending fatigue resistance of gear is carried out. The biomimetic surface morphology was prepared on the gear surface by a 4.5-kW Nd:YAG pulsed laser. The results showed that the fatigue lives of all of the biomimetic gears were much longer than that of the as-received gear. The bending fatigue resistance was improved by the biomimetic surface morphology. The bending fatigue resistant mechanism of biomimetic gear is discussed.

The purpose of this investigation was to explore the influence of the biomimetic surface morphology on the modal properties of gear. Firstly, a involute cylinder gear model had been created, and the biomimetic surface morphology had been established on the gear tooth flanks. Secondly, the modal analysis of the ordinary gear and biomimetic gear has been investigated separately through FEM method. Results showed that the maximum amplitudes and the ten natural frequencies of biomimetic gear were obviously lower than that of the ordinary gear, but the modal shape of the two kinds of gears were almost the same. The biomimetic surface morphology could improve the dynamic characteristics and reliability of gear in the future.

The flywheel energy storage technology is a kind of method that converts electrical energy into kinetic energy in store. The flywheel energy storage system (FESS) is usually used for renewable energy system such as wind turbine generator system (WTGS) to adjust the quality of output power. Droop control is a kind of control technology to regulate the active power and reactive power in micro-grid. In this paper, we introduced a method to combine the droop control with FESS and designed the control topology. The droop control method was applied to control the part of inverter in FESS. By controlling the output frequency and the voltage amplitude of WTGS-FESS system, we can regulate the output of the inverter as a promotion in smoother active power and reactive power.

Based on the experimental optimal designing method, the experimental plan was set up. In order to study anti-fatigue capability of the gear, the laser engraving technology was applied to process the grid type bionic micro-morphology texture on the gear teeth surface. Different anti-fatigue characteristics of the bionic samples were obtained through analyzing the fatigue tests results. The results showed that the pitting ratio of the gear specimens with the grid micro-morphology had been decreased obviously. The grid bionic surface micro-morphology on the gear had improved the anti-fatigue capability of the gear to 139%, and mechanism of anti-fatigue of the bionic gear was ascribed to “Dam Effect”, laser strengthen and changing of lubrication.

Job scheduling and AGV scheduling in FMS are regarded as two independent problems by most researchers. Their isolation ignores AGV’s use conflicts in the job scheduling and leads to low average equipment utilization. We point out the necessity for the job scheduling to integrate with AGV scheduling through analyzing scheduling problem of a specific type of FMS with single AGV and single buffer area. Then a corresponding mathematic model for integrated scheduling is presented based on the problem description and constraints for scheduling. A specific FMS is adopted to validate this integrated scheduling model. Based on data from this FMS, the model is performed through genetic algorithm with appropriate parameters. And job’s processing sequences as well as AGV’s moving path are obtained from the optimal gene order. The experiment result of this scheduling model adopting genetic algorithm shows good computing efficiency and equipment utilization.

Deformability and compact energy density are urgently needed for power supplies to cater to today's increasingly multifunctional consumer electronics. Here, a flexible and self-supporting composite electrode, in which manganese oxide directly grows on surfaces of the reduced graphene oxide and the interconnected porous framework of the hydrogel is retained, was fabricated by electrochemical deposition of manganese dioxide in graphene hydrogel. Thanks to the contribution of pseudocapacitance and the unchanged volume of the hydrogel, the introduction of manganese oxide helps to lift the volumetric capacitance of the electrode by more than 400%, from 103.6 to 417.8 F cm−3. The solid-state asymmetric supercapacitor, composed of an activated carbon electrode and an as-prepared composite electrode, has a capacitance of 67.7 F cm−3. The series connected supercapacitor not only successfully illuminates a white light-emitting diode bulb, but also works steadily under deformation conditions.