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The capture and conversion of carbon dioxide (CO2) into valuable chemical products under mild conditions is an important and challenging approach for contemporary industry. Carboxylic acid ligands are widely used in the development of functionalized metal organic framework materials due to their excellent stability. Herein, a novel mixed-metal organic framework Cu-TCPP(Fe) was assembled from iron-(Fe)-porphyrin ligands, which can efficiently catalyze the reaction of propargylic amines and CO2 to synthesize 2-oxazolidinones. [ABSTRACT FROM AUTHOR]

In this paper, we study a type of p-Laplacian equation - Δ p u = λ u p - 2 u + u q - 2 u , x ∈ R N , with prescribed mass ∫ R N | u | p 1 p = c > 0 , where 1 < p < q < p ∗ : = pN N - p , p < N , λ ∈ R is a Lagrange multiplier. Firstly, we prove the existence of normalized solutions to p-Laplacian equations and provide accurate descriptions; secondly, we discuss the existence of ground states; finally, we study the radial symmetry of normalized solutions in the mass supercritical case. Besides, we also study normalized solutions to p-Laplacian equation with a potential function V(x) - Δ p u + V (x) u p - 2 u = λ u p - 2 u + u q - 2 u , x ∈ R N , under different assumptions on q and the constraint norm c, we prove the existence, nonexistence, concentration phenomenon and exponential decay of normalized solutions. [ABSTRACT FROM AUTHOR]

In this paper, we first investigate the regularity of finite energy solutions to the following Wolff type integral system: { u (x) = R 1 (x) W β , γ (v p u r) (x) , u (x) > 0 , x ∈ R N , v (x) = R 2 (x) W β , γ (u q v s) (x) , v (x) > 0 , x ∈ R N , where γ > 1 , β > 0 , β γ < N , W β , γ is the Wolff potential, R 1 , R 2 are double bounded functions in R N and p , q > max ⁡ { 1 , γ − 1 } , r , s ≥ 0 with p − s ≥ q − r > − γ + 1. We exploit the regularity lifting lemma to obtain the optimal integrability, boundedness and decaying property of finite energy solutions to the system. Secondly, we establish sharp pointwise estimates of positive finite energy solutions to the p -Laplacian and k -Hessian systems related to the above integral system, by using the previous regularity results, the interior Hölder estimates of solutions for the corresponding differential systems and a doubling lemma of Poláčik, Quittner and Souplet (Duke Math. J.,2007). These extend Vétois's decay results (Indiana Univ. Math. J.,2019) on the positive solutions of Laplacian systems to the p -Laplacian and k -Hessian cases. We remark that our methods do not need Harnack type inequalities and it can be applied to deal with the solutions without radial structures. As far as we know, this is the first attempt to derive sharp decay estimates for possibly non-radial solutions involving k -Hessian operators. We also obtain some decay estimates of the gradients at infinity. [ABSTRACT FROM AUTHOR]

Aims: Combining multiple features of UAV-based multispectral images with the stacking ensemble model, to improve the feasibility and accuracy of evaluating water stress in winter wheat. Methods: UAV-based multispectral images of winter wheat with different moisture treatments were acquired, from which the features such as spectrum, texture, and color moments were extracted. The soil moisture content (SMC) as well as fuel moisture content (FMC), plant moisture content (PMC), and above-ground biomass (AGB) were collected for charging the degree of water stress. The basic models were used to build ensemble models such as stacking and weighted stacking (WE-stacking), and we estimated SMC, FMC, PMC and AGB combined with multiple features. The performance of these models was evaluated. Results: The more severe the water stress, the lower values of SMC, FMC, PMC and AGB were obtained with estimation models. The performance of estimation models based on multi-feature fusion outperformed single feature in the evaluation of winter-wheat water stress. In the estimation of SMC, both stacking and WE-stacking models performed better than the basic models. Compared to the stacking model, the WE-stacking model had higher accuracy, with R2 increased between 1.98% and 3.62% at different soil depths. The WE-stacking model with multi-feature fusion still had sufficient stability and high accuracy in FMC, PMC and AGB estimation, with R2 of 0.866, 0.881 and 0.884, respectively. Conclusions: The multi-feature fusion of UAV multispectral images combined with WE-stacking model has great application potential and provides technical support in evaluating crop water stress. [ABSTRACT FROM AUTHOR]

In this paper we study the nonlinear Bose–Einstein condensates Schrödinger system { − Δ u 1 − λ 1 u 1 = μ 1 u 1 3 + β u 1 u 2 2 + κ (x) u 2 in R 3 , − Δ u 2 − λ 2 u 2 = μ 2 u 2 3 + β u 1 2 u 2 + κ (x) u 1 in R 3 , ∫ R 3 u 1 2 = a 1 2 , ∫ R 3 u 2 2 = a 2 2 , where a 1 , a 2 , μ 1 , μ 2 , κ = κ (x) > 0 , β < 0 , and λ 1 , λ 2 are Lagrangian multipliers. We use the Ekeland variational principle and the minimax method on manifold to prove that this system has a solution that is radially symmetric and positive. [ABSTRACT FROM AUTHOR]

By bifurcation and topological methods, we study the existence/nonexistence and multiplicity of one-sign or nodal solutions of the following k-th mean curvature problem in Minkowski spacetime r N − k v ′ 1 − v ′ 2 k ′ = λ N C N k r N − 1 H k (r , v) in (0 , R) , | v ′ | < 1 in (0 , R) , v ′ (0) = v (R) = 0. As a previous step, we investigate the spectral structure of its linearized problem at zero. Moreover, we also obtain a priori bounds and the asymptotic behaviors of solutions with respect to λ. [ABSTRACT FROM AUTHOR]

Exploring the potential association between peripheral blood leukocyte counts and breast cancer risk by Mendelian randomization (MR) analysis methods. Genetic data related to peripheral blood sorting counts of leukocytes were collected from a genome-wide association study by Blood Cell Consortium (BCX). Single nucleotide polymorphic loci predicting peripheral blood sorting counts of these leukocytes were selected as instrumental variables according to the correlation assumption, independence assumption and exclusivity assumption of MR. The data on breast cancer and its subtypes were obtained from Breast Cancer Association Consortium (BCAC) and FinnGen Consortium. In this study, the Inverse-Variance Weighted (IVW), Weighted Median, MR-Egger, Maximum Likelihood (ML), MR-PRESSO and Constrained Maximum Likelihood and Model Averaging (cML-MA) methods of random effects models were used for MR analysis. Cochran's Q analysis, and MR-Egger intercept analysis were applied for sensitivity analysis. IVW and cML-MA were considered the primary analytical tools, and the results of the other 4 MRs were used as complementary and validation. The results suggest that there is no significant causal relationship between leukocyte count and breast cancer risk (IVW OR = 0.98 [95% CI: 0.93–1.03], p-value = 0.35; CML-MA OR = 1.01 [95% CI: 0.98–1.05], p-value = 0.51). In addition, we analyzed whether there was a potential correlation between the five main types of categorized leukocyte counts and different breast cancer subtypes. We did not find significant evidence to support a significant correlation between leukocyte counts and breast cancer subtypes. [ABSTRACT FROM AUTHOR]

In this paper, we are concerned with the optimal integrability, regularity and symmetry of integrable solutions for the following Wolff type integral systems: (1.1) { u (x) = R 1 (x) W β , γ (v q) (x) , u (x) > 0 , x ∈ R N , v (x) = R 2 (x) W β , γ (u p) (x) , v (x) > 0 , x ∈ R N , where γ > 2 , β > 0 , β γ < N , p , q > γ − 1 with γ − 1 p + γ − 1 + γ − 1 q + γ − 1 = N − β γ N , R 1 , R 2 are double bounded in R N and W β , γ (h) (x) : = ∫ 0 ∞ [ ∫ B t (x) h (y) d y t N − β γ ] 1 γ − 1 d t t. Firstly, we prove the optimal integrability and boundedness of solutions (u , v) ∈ L p + γ − 1 (R N) × L q + γ − 1 (R N) for system (1.1) , by constructing a nonlinear, contracting operator and applying the regularity lifting lemma of C. Ma, W. Chen and C. Li (2011) [21]. Moreover, we exploit the general regularity lifting theorem to derive the Lipschitz continuity of u and v when R 1 ≡ R 2 ≡ 1 in R N. These extend the above important results of C. Ma, W. Chen and C. Li to γ > 2. We also prove that u and v vanish at infinity. As the corollaries of the above results, we obtain the optimal integrability, boundedness and the property of vanishing at infinity of integrable solutions for the corresponding γ -Laplace and k -Hessian systems. Secondly, we use the method of moving planes in integral forms to prove the symmetry and monotonicity of solutions (u , v) ∈ L p + γ − 1 (R N) × L q + γ − 1 (R N) for system (1.1) when R 1 ≡ R 2 ≡ 1 in R N , which extends the useful result of W. Chen and C. Li (2011) [5] to γ > 2. In comparison with the above two papers, Minkowski's inequality is crucial in our proofs. We believe that our arguments can be used to prove similar results for other Wolff type integral systems when γ > 2. [ABSTRACT FROM AUTHOR]

In this paper, we study the p-Laplacian equation with a L p -norm constraint: âˆ' Î" p u = λ | u | p âˆ' 2 u + ÎĽ | u | q âˆ' 2 u + g (u) in R N , ∫ R N | u | p d x = a p , where N â©ľ 2, a > 0, 1 < p < q â©˝ p ÂŻ â‰" p + p 2 N , ÎĽ ∈ R , g ∈ C (R , R) and λ ∈ R is a Lagrange multiplier, which appears due to the mass constraint ‖ u ‖ p = a. We assume that g is odd and L p -supercritical. When q < p ÂŻ and ÎĽ > 0, we use Schwarz rearrangement and Ekeland variational principle to prove the existence of positive radial ground states for suitable ÎĽ. When q = p ÂŻ and ÎĽ > 0 or q â©˝ p ÂŻ and ÎĽ â©˝ 0, with an additional condition of g, we obtain a positive radial ground state if ÎĽ lies in a suitable range, by the Schwarz rearrangement and minimax theorems. Via a fountain theorem type argument, with suitable ÎĽ ∈ R , we obtain infinitely many radial solutions for any N â©ľ 2 and establish the existence of infinitely many nonradial sign-changing solutions for N = 4 or N â©ľ 6. In any case mentioned above, the range of ÎĽ depends on the value of a : | ÎĽ | can be large if a > 0 is small. [ABSTRACT FROM AUTHOR]

In this paper, we study the p-Laplacian equation with a L p -norm constraint: − Δ p u = λ | u | p − 2 u + μ | u | q − 2 u + g (u) in R N , ∫ R N | u | p d x = a p , where N ⩾ 2, a > 0, 1 < p < q ⩽ p ¯ ≔ p + p 2 N , μ ∈ R , g ∈ C (R , R) and λ ∈ R is a Lagrange multiplier, which appears due to the mass constraint ‖ u ‖ p = a. We assume that g is odd and L p -supercritical. When q < p ¯ and μ > 0, we use Schwarz rearrangement and Ekeland variational principle to prove the existence of positive radial ground states for suitable μ. When q = p ¯ and μ > 0 or q ⩽ p ¯ and μ ⩽ 0, with an additional condition of g, we obtain a positive radial ground state if μ lies in a suitable range, by the Schwarz rearrangement and minimax theorems. Via a fountain theorem type argument, with suitable μ ∈ R , we obtain infinitely many radial solutions for any N ⩾ 2 and establish the existence of infinitely many nonradial sign-changing solutions for N = 4 or N ⩾ 6. In any case mentioned above, the range of μ depends on the value of a : | μ | can be large if a > 0 is small. [ABSTRACT FROM AUTHOR]

This study sought to investigate the association between microRNA-29a (miR-29a) and cardiomyocyte apoptosis in diabetic cardiomyopathy (DCM). DCM rat model was established by treating rats with streptozotocin (STZ), followed by injection of NC or miR-29a-3p mimics into the myocardium of rats. High glucose (HG)-treated H9c2 cells were transfected with NC and miR-29a-3p mimics. DCM rats presented elevated levels of blood glucose, HbA1c, blood pressure, urine output, decreased body weight and cardiac contractile function after modeling. MiR-29a was lowly expressed in STZ-treated rats and HG-treated H9c2 cells. Upregulation of miR-29a improved cardiac structure and function and attenuated, alleviated myocardial histological abnormalities and fibrosis and lowered cardiomyocyte apoptosis in DCM rats. Meanwhile, HG promoted H9c2 cell apoptosis, while miR-29a overexpression attenuated the function of HG. Compared with control group, the protein expression of Bax, cleaved-caspase3 and Bak1 in DCM and HG groups were significantly upregulated, and the expression of Bcl-2 and Mcl-1 was downregulated, while miR-29a overexpression exerted opposite effect. Bioinformatics prediction method and western blot revealed that miR-29a directly targeted Bak1 and downregulated Bak1 expression. Overall, miR-29a regulated STZ- and HG-induced cardiomyocyte apoptosis by targeting Bak1, providing a novel understanding of the pathogenesis of DCM. [ABSTRACT FROM AUTHOR]

The key parameter for this device fabrication is to control the thickness of the entire light-emitting device, as a lower thickness would enable the light-emitting device to endure a lower bending radius. The polymer light-emitting electrochemical cell (PLEC) is another type of device that is suitable for making intrinsically stretchable devices, which does not have the high-driving-voltage issue. As a result, the resulting stretchable PLED showed a maximum device brightness of ~7450 cd/m SP 2 sp with a high stretchability of 100% strain. [Extracted from the article]

The Arrhenius equation is generally adopted for the application of accelerated aging in laboratory tests, and activation energy is one of the important parameters in the equation. In most cases, activation energy was determined by obtaining a series of viscosity data at different temperature, which was a complex process. Therefore, this study aimed to analyze the correlation between activation energy for viscous flow (Eη) and molecular characteristics as well as rheological properties and obtain easily measurable properties that can be used to predict Eη. In this study, nine base asphalt binders were subjected to accelerated aging, and their viscosity, rheological properties, and molecular weight distribution were tested. Small molecule size (SMS) content was the most strongly correlated parameter with Eη for unaged asphalt binder compared with medium molecule size (MMS) content and large molecule size (LMS) content from the result of gray relation analysis. The correlation further weakened after considering aging, which indicated that the change in molecular distribution of asphalt binder may not be the decisive parameter in determining the change in Eη of asphalt binder. Single regression analysis showed a significant correlation between rheological performance parameters and Eη. It was feasible to predict Eη based on the failure temperature and obtain the modified Arrhenius equation. The modified equation could be used to calculate the accelerated aging factor and obtain the aging asphalt and accurate aging status of asphalt binders. By verification, the average error in predicting the Eη of the asphalt binder using the modified equation was less than 5%. [ABSTRACT FROM AUTHOR]

Asphalt mixture performance is attributed to morphological interlocking and physiochemical interaction between binder and aggregate. Many studies fostered the adhesion and bonding characteristics of many binders without conferring the interfacial interaction. To realistically understand the binder cohesion strength, this study investigates the impact of interfacial interaction on the binder colloid structure. An innovative experimental method was developed using the pull-off and gel permeation chromatography tests to investigate the binder/aggregate interface interaction from molecular and mechanical standpoints. The results showed success for the developed method to pursue the mechanism of the binder/aggregate interface interaction and evaluate the resulting molecular diffusion. Two mechanisms were distinguished for molecular diffusion, depending on the percentage of light components. The abundant light components can mobilize the heavy fractions, whereas binder colloids with limited light components have a molecular diffusion for light fractions only. The binder film portion near the aggregate surface has higher cohesion strength than the upper portion, where a strong correlation was proven between the decrease in the cohesion strength and the molecular diffusion due to the interfacial interaction. A robust prediction model with R2 of 0.90 was developed for the binder cohesion strength, where both the molecular composition and the molecular mobility due to interfacial interaction have significant impacts. As the accretion of heavy fractions strengthens the cohesion strength, the molecular diffusion mechanism, which mobilizes the heavy fractions toward the interface, further improves the cohesion strength of the binder film portion near the interface. • Interfacial interaction changes the molecular structure of the binder film. • Molecular diffusion mechanism depends on binder molecular composition. • Binder cohesion decreases with the film thickness due to interfacial interaction. • Binder cohesion is correlated to molecular composition and diffusion. • RAP binder addition undermines molecular diffusion under interfacial interaction. [ABSTRACT FROM AUTHOR]

• A real-time online fault diagnosis framework for simultaneous diagnosis of normal resistance alterations and resistance-alteration-based faults is proposed. • Based on the observability of resistance, the layout method of the node wind pressure sensor is proposed. • It is proved that the mine ventilation network can be divided into linear topology and star topology. • A multiple faults diagnosis algorithm for ventilation system with continuous observation and dynamic update is proposed. • The effectiveness of the framework and algorithm is verified in the coal mine ventilation system. Resistance-alteration-based multiple-fault diagnosis of mine ventilation systems is essential to ensuring the safety of mine production. The basic assumptions, definitions, framework, theory, algorithms and experiments regarding the resistance-alteration-based multiple-fault diagnosis of mine ventilation systems are systematically studied here. First, the problems of the single-fault assumption in the conventional ventilation system fault diagnosis framework are analyzed, and a real-time online multiple-fault diagnosis framework is proposed. Then, based on the theory of resistance observability, the sensor layout scheme is optimized, the properties of the ventilation subnetwork are studied, and the interpretable resistance-alteration-based multiple-fault diagnosis (RMFD) algorithm is designed. Finally, a diagnosis experiment with multiple faults was carried out for a real coal mine. The experimental results show that the RMFD algorithm can achieve 100% accuracy of identification and positioning at the ventilation subnetwork level and can perform quantitative resistance-alteration analysis for k − 1 roadways within a k -order star subnetwork, which verifies the effectiveness of the real-time online multiple-fault diagnosis framework and the RMFD algorithm. This study achieves real-time online multiple-fault diagnosis of mine ventilation systems and provides a theoretical reference and technical support for the intelligentization of mine ventilation systems and similar fluid networks. [ABSTRACT FROM AUTHOR]

Time–frequency analysis methods represent an efficacious approach to process data derived from full-waveform acoustic logging. This research proposes a coupled time–frequency analysis method that synergistically incorporates ensemble empirical mode decomposition, fractional Fourier transform, Choi–Williams (CW) distribution and adaptive filtering. This coupled method facilitates the comprehensive analysis of full-waveform acoustic logging signals within rigid geological formations. Specifically, it is designed to explore the time–frequency characteristics of shear wave (S-wave) within the context of igneous reservoirs. The coupled time–frequency analysis method significantly ameliorates the time–frequency coupling phenomenon of full-waveform acoustic logging signal. This coupled method is applied across different wells to confirm its wide-ranging applicability and study the time–frequency characteristics response of S-wave through the information of the peak time of the S-wave, the main frequency and the amplitude of the CW distribution. [ABSTRACT FROM AUTHOR]

• The estimated performance of 9 global ET products under extreme climatic conditions was evaluated. • Extreme climate includes high temperature, high VPD and drought. • GLEAM_v3.6b and REA perform better under extreme climatic conditions. • The Americas region is most affected by extreme climate. Terrestrial Evapotranspiration (ET) is an important process for understanding regional or global water, energy, and carbon cycles, and with the development of satellite observations and increased research investment, grid ET products covering a broad spatial extent are becoming more readily available. However, as global warming becomes a reality and extreme climate events occur worldwide, existing studies do not go far enough to verify that these grid products can still be used under extreme climate conditions. This study evaluates nine global ET products, including land surface reanalysis products (GLDAS_CLSM, GLDAS_NOAH, ERA5, and FLDAS), remote sensing (RS) products (GLEAM_v3.6b, MOD16A2, and PMLv2), and multi-source data fusion products (REA and Synthesized), using observations from 153 flux towers worldwide. The objective is to evaluate their performance in estimating ET under extreme climatic conditions (high temperature, high vapor pressure deficit (VPD), and drought). The results indicate that the estimation accuracy of all ET products is significantly reduced under extreme climatic conditions, showing high uncertainty, and this impact is most severe in the Americas (AM) region. Overall, multi-source data fusion products showed the best estimation performance and were less affected by extreme climatic conditions. Among the remote sensing modeling products, GLEAM_v3.6b showed the best performance, while MOD16A2 has the lowest estimation accuracy. Land surface reanalysis products were most affected by extreme conditions, with CLSM and NOAH showing similar performance and ERA5 having the largest errors (RMSE_ERA5 = 1.699 mm/d, MAE_ERA5 = 1.294 mm/d). The ET products show significant error fluctuations and overestimation (PBias > 0.5) in most of North America, and there is a decline in simulation accuracy in arid and semi-arid regions near 30°N, with most ET products showing overestimation. The most significant errors were observed in cropland areas (CRO) and deciduous broadleaf forest areas (DBF), with significant overestimation in mixed forest areas (MF). The results of this study provide valuable insights for researchers in selecting ET products under extreme climatic conditions and encourage product developers to consider uncertainty under such conditions, thereby improving product accuracy. [ABSTRACT FROM AUTHOR]

• New texture indices were constructed by texture metrics and effectively used to estimate LAI of maize. • The potential of UAV-based thermal infrared sensor for estimating LAI was proved. • The combination of UAV-based multispectral and thermal infrared data improved the estimation accuracy of LAI. • The RFR model had the strong robustness and achieved the best performance on LAI estimation. Crop leaf area index (LAI) is one of the important indicators to evaluate crop growth and guide field management, and can be used to predict crop yield. Spectral and thermal information extracted by multispectral (MS) and thermal infrared (TIR) sensors mounted on an unmanned aerial vehicle (UAV) can be used for LAI estimation. Image texture is sensitive to the changes in crop surface grayscale or color characteristics, and can be combined with spectral and thermal information to estimate the LAI. But single texture metric has limitations in LAI estimation. Therefore, the purpose of this study is to construct new texture indices based on texture metrics extracted from MS and TIR images, and combined spectral and thermal information to enhance the estimation accuracy of maize LAI. Three replicates of maize experiments under different irrigation treatments were conducted in 2020. The MS and TIR sensors were mounted on a UAV to acquire maize canopy images during critical growth stages and acquire field LAI value of samples synchronously. The LAI estimation models were established using MS data, TIR data, as well as their combination. These models were constructed by Back Propagation Neural Network (BPNN), Partial least squares regression (PLSR), and Random Forest Regression (RFR). Finally, the performance of LAI estimation models was evaluated by the coefficient of determination (R2), root mean square error (RMSE) and relative root mean square error (rRMSE). Results shown that: (i) Among the eight kinds of texture metrics extracted from MS and TIR images, the texture metric mean (MEA) has the best performance. Compared with single texture metrics, texture indices constructed by different metrics has stronger correlation with LAI. (ii) Adding texture indices to estimation models significantly improved model accuracy, especially multispectral three-texture index(MS-TTI) has higher LAI estimation potential than thermal infrared three-texture index(TIR-TTI). (iii) Compared with the use of MS or TIR data alone, the estimation model constructed by combining MS data and TIR data have better performance. The best estimation model obtained by the RFR method (R2 = 0.862, RMSE = 0.246 and rRMSE = 10.20 %) further improved the LAI estimation of maize, with R2 increasing by 6.55 % and 14.48 %, respectively. In conclusion, the combination of MS and TIR data can effectively improve the estimation accuracy of maize LAI, and also provide a feasible method for monitoring crop growth. [ABSTRACT FROM AUTHOR]

We study the normalized solutions of the fractional nonlinear Schrödinger equations with combined nonlinearities (- Δ) s u = λ u + μ | u | q - 2 u + | u | p - 2 u in R N , and we look for solutions which satisfy prescribed mass ∫ R N | u | 2 = a 2 , where N ≥ 2 , s ∈ (0 , 1) , μ ∈ R and 2 < q < p < 2 s ∗ = 2 N / (N - 2 s) . Under different assumptions on q < p , a > 0 and μ ∈ R , we prove some existence and nonexistence results about the normalized solutions. More specifically, in the purely L 2 -subcritical case, we overcome the lack of compactness by virtue of the monotonicity of the least energy value and obtain the existence of ground state solution for μ > 0 . While for the defocusing situation μ < 0 , we prove the nonexistence result by constructing an auxiliary function. We emphasis that the nonexistence result is new even for Laplacian operator. In the purely L 2 -supercritical case, we introduce a fiber energy functional to obtain the boundedness of the Palais–Smale sequence and get a mountain-pass type solution. In the combined-type cases, we construct different linking structures to obtain the saddle type solutions. Finally, we remark that we prove a uniqueness result for the homogeneous nonlinearity ( μ = 0 ), which is based on the Morse index of ground state solutions. [ABSTRACT FROM AUTHOR]

Grassland degradation can substantially reduce soil carbon sequestration capacity. However, the effects of grassland degradation on soil organic carbon (SOC) density remain unquantified in high‐altitude alpine meadows. In this study, the response and controlling mechanisms of topsoil (0–20 cm) organic carbon were explored in a field survey involving 11 pairs of healthy versus severely degraded plots of high‐altitude (above 4000 m) alpine meadows, as well as three short‐term (3–5 years) fencing restoration projects, across the source of the Yellow River in August of 2020 and 2021. The results showed that 0–20 cm root biomass, SOC content (SCC), and density (SCD) of healthy meadows averaged 533.7 ± 291.9 g/m2 (mean ± S.D), 21.17 ± 9.36 g/kg, and 4.54 ± 1.64 kg C/m2, respectively. Root biomass, SCC, and SCD were markedly reduced by 63.0%, 33.2%, and 17.6% in severely degraded grassland compared with healthy meadows. The SCC and SCD averaged 7.92 ± 2.21 g/kg and 2.2 ± 0.9 kg C/m2 in fencing plots, respectively, and were not significantly different from severely degraded meadows, suggesting a limited improvement in SOC from short‐term fencing restoration. Analysis of a piecewise structural equation model revealed that the effect of degradation on SCD (indicated by the difference in SCD between paired healthy and degraded meadows) was jointly regulated by the differential surface root biomass and site altitude, with a total positive effect of 0.39 and 0.26, respectively. Our findings indicate the losses of topsoil organic carbon stock caused by grassland degradation are root biomass‐ and altitude‐dependent, supporting the notion that antecedent prevention of degradation, more than subsequent restoration, should be the highest priority in the adaptive management of alpine meadows in harsh high‐altitude regions. [ABSTRACT FROM AUTHOR]

Abstract We study the Hénon–Lane–Emden conjecture, which states that there is no non-trivial non-negative solution for the Hénon–Lane–Emden elliptic system whenever the pair of exponents is subcritical. By scale invariance of the solutions and Sobolev embedding on S N − 1 , we prove this conjecture is true for space dimension N = 3 ; which also implies the single elliptic equation has no positive classical solutions in R 3 when the exponent lies below the Hardy–Sobolev exponent, this covers the conjecture of Phan–Souplet [22] for R 3. [ABSTRACT FROM AUTHOR]

• Radar image and spectral images were fused for monitoring soil salinity. • Soil salinity inversion models were built based on Sentinel-1/2 fusion and machine learning. • GS was used to fuse images of Sentinel-1 and Sentinel-2. In the application of satellite remote sensing data to salinity inversion in bare soil, multispectral satellites enjoy richer wavelength bands compared with synthetic aperture radar (SAR), but their vulnerability to cloudy weather limits the inversion accuracy. In contrast, SAR has stronger penetration, is less affected by cloudy weather, and can work around the clock. Therefore, in order to monitor soil salinity over a longer period of time and under various climatic conditions, and to further improve the accuracy of salinity inversion, we fused Sentinel-1 and Sentinel-2 images and investigated the feasibility of SAR and multispectral satellite image fusion in salinity inversion in this paper. And we conducted experiments in Hetao Irrigation Area, Inner Mongolia, China. Gram-Schmidt(GS) was used to fuse Sentinel-1 and Sentinel-2 images at the same time, and maximum-normalization was carried out on the DN value of the fused image. Then some remote indices conducted with the normalized DN, together with high relevant fused single bands were input into Back Propagation(BP), Support Vector Machine(SVM), Random Forest(RF) as independent variables after two-tailed significance test and Variable importance in projection(VIP) selection, for soil salinity inversion model construction. Finally, the inversion results of the study area were evaluated with R2, RMSE, RPD, RSS, and RPIQ. The results of this study showed that the bare soil salinity inversion based on the fusion of VV(Sentinel-1) and Sentinel-2 had a higher accuracy than that on the fusion of VH (Sentinel-1) and Sentinel-2 image and that without the fusion. Among the three machine learning models, random forest (RF) achieved the most satisfying results (R2 = 0.801, RMSE = 0.686), followed by SVM(R2 = 0.624, RMSE = 0.875) and BP(R2 = 0.613, RMSE = 0.918). This study demonstrated the feasibility of fusing Sentinel-1 radar images with Sentinel-2 multispectral images to improve the accuracy of soil salinity inversion, and constructed the soil salinity inversion model based on machine learning and GS fusion. [ABSTRACT FROM AUTHOR]

In this paper, we first prove the uniqueness of positive ground state solution for the following Kirchhoff equation in R 3 with constant coefficients { − ( a + b ∫ R 3 | ∇ u | 2 ) Δ u + c u = d | u | p − 1 u in R 3 , u > 0 , u ∈ H 1 ( R 3 ) , where a , b , c , d > 0 are positive constants, 3 < p < 5 . Then we use the uniqueness result to obtain the existence and concentration theorems of positive ground state solutions to the following Kirchhoff equation with competing potential functions − ( ε 2 a + ε b ∫ R 3 | ∇ u | 2 ) Δ u + V ( x ) u = K ( x ) | u | p − 1 u in R 3 , for a sufficiently small positive parameter ε . [ABSTRACT FROM AUTHOR]

• The 3D internal crack cracking process and propagation path were visualized by 3D Internal Laser-Engraved Crack technology. • The fracture behavior of brittle materials with 3D internal cracks under uniaxial compression is discussed. • The mode I/II/III propagation simulation of 3D internal crack under uniaxial compression is realized based on fracture mechanics theory. Uniaxial compression tests are one of the classic tests of solid mechanics. However, there remain some unsolved problems involving the test methods and numerical simulation. In the present study, in view of the difficulties in the manufacture of real internal cracks, glass, a classical material whose brittleness is quite close to that of natural rock material, is selected to generate pure closed internal cracks using 3D Internal Laser-Engraved Crack (3D-ILC) technology. Through the uniaxial compression test, we observe that the failure of specimens originates from the pre-existing internal crack. First, wing cracks are generated around it, which then propagate. As the load reaches the maximum bearing capacity, the later tensile crack eventually leads to the failure of the specimen. This test method can be used to observe and study the crack propagation process, failure law, failure mode and characteristic load of brittle materials. In the numerical analysis, adaptive grid method is used for grid division and update. The distribution of K I , K II , and K III at the crack tip is obtained by M-Integral, and the crack propagation is simulated in combination with the maximum tensile stress (MTS) criterion. In terms of numerical simulation, the mode I/II/III propagation simulation of 3D internal crack is successfully realized, which is of great significance. At present, the research of 3D crack propagation and internal crack propagation has encountered bottlenecks in theory, experiment and numerical simulation. It is hoped that the experimental and numerical simulation methods in this paper can provide some reference. [ABSTRACT FROM AUTHOR]

Accurate determination of crops growth period plays an important role in field management and agricultural decision-making. The current work mostly extracts the crop normalized difference vegetation index curve from multi-temporal data and identifies the crop phenology based on its trend or special nodes. However, these time-series-based identification methods are difficult to be applied to practically crop monitoring tasks. In this paper, the unmanned aerial vehicle remote sensing platform is used to collect the multi-spectral images of the experimental field and identify the sunflower growth period based on the different population features during its different growth periods. According to the actual field management needs, this study obtains the plot-level sunflower growth period result by analyzing statistically the distribution area of different sunflower periods in a field plot. This study uses the data of 2018 in the study area to build the model and test its performance on the data of 2019. Through comparative experiments, PSPNet can achieve a good balance between accuracy and efficiency in this study. Further, given to time-series relationship between the adjacent growth periods classification, this paper proposes an improved loss function to weight different types of misclassification to optimize model performance. The results show that improved PSPNet with proposed weighted loss function achieves the optimal recognition accuracy of 89.01%, which provides a solution for sunflower growth period recognition based on the single-phase data. [ABSTRACT FROM AUTHOR]

This paper is concerned with the Dirichlet problem of the asymptotically linear wave equation in a n-dimensional ball with radius R, where $$n>1$$ and g( t, x, u) is radially symmetric in x and T-periodic in time. An interesting feature is that the solvable of the problem depends on the space dimension n and the arithmetical properties of R and T. Based on the spectral properties of the radially symmetric wave operator, we use the saddle point reduction and variational methods to construct at least three radially symmetric solutions with time period T, when T is a rational multiple of R and g( t, x, u) satisfies some monotonicity and asymptotically linear conditions. [ABSTRACT FROM AUTHOR]

A highly stretchable supercapacitor is developed from a family of nitrogen‐doped core‐sheath carbon nanotube array as an elastic electrode. It displays a specific capacitance of 30.8 mF cm−2 with the strain up to 400%; the specific capacitance can be maintained by 96% after stretching for 1000 cycles. The unique 3D cross‐linked structure in the elastic electrode contributes to the high property. [ABSTRACT FROM AUTHOR]

In this paper, we consider the periodic-Dirichlet problem for a forced nonlinear wave equation with resonance u t t − Δ u = μ u + a ( t , x ) | u | p − 1 u in a n -dimensional ball. Under some suitable assumptions on μ , p and a ( t , x ) , we prove the existence of infinitely many radially symmetric time-periodic solutions for the problem by variational methods. [ABSTRACT FROM AUTHOR]

The emergence of wearable electronics and optoelectronics requires the development of devices that are not only highly flexible but can also be woven into textiles to offer a truly integrated solution. Here, we report a colour-tunable, weavable fibre-shaped polymer light-emitting electrochemical cell (PLEC). The fibre-shaped PLEC is fabricated using all-solution-based processes that can be scaled up for practical applications. The design has a coaxial structure comprising a modified metal wire cathode and a conducting aligned carbon nanotube sheet anode, with an electroluminescent polymer layer sandwiched between them. The fibre shape offers unique and promising advantages. For example, the luminance is independent of viewing angle, the fibre-shaped PLEC can provide a variety of different and tunable colours, it is lightweight, flexible and wearable, and it can potentially be woven into light-emitting clothes for the creation of smart fabrics. [ABSTRACT FROM AUTHOR]

Normalized difference vegetation index (NDVI) can be used as an ideal indicator of how the crops grow, with which the crops in different growing stages, harmful insects and diseases, water and fertilizer, and the yields can be well predicted. However, the accuracy of NDVI does not remain unchanged due to the ever-changing environmental factors, apart from the impact from the crops growing factors in different stages. The article investigates, using GreenSeeker, the soybean NDVI of its three growing stages of seeding, flowering & podding and maturing in successive hours as the testing unit, for a more accurate monitoring of NDVI affected by air temperature, humidity, solar radiation, and wind speed, etc. in different periods of a day. The results show that the soybean NDVI values, being dynamic in different periods of a day, become smaller from 08:00 or 09:00 am in the morning, reach the valley in 14:00 pm in the afternoon, then give a gradual rise, the whole dynamic process is similar to a quasi-parabola. Moreover, the soybean NDVI values demonstrate different daily variation ranges in different soybean growing stages. From 08:00 am to 18:00pm, the biggest daily variation ranges are respectively among 0.13-0.23, 0.08-0.17 and 0.09-0.19, the biggest relative daily variation ranges are respectively among 20%-26%, 9%-19% and 11%-24%. The correlation study of the soybean NDVI values and the environment meteorological factors show that the changes in soybean NDVI values in its three growing stages are upon great influence by the solar radiation, air temperature, humidity and the wind speed. In four meteorological factors, the solar radiation and air temperature have a negative correlation with the soybean NDVI values at three stages (R2 =0.424, 0.503, 0.631 and 0.602, 0.743, 0.757), humidity shows a positive correlation with the soybean NDVI values(R2 =0.281, 0.435 and 0.654), and the wind speed exerts different influences in different soybean growing stages, specifically, a negative correlation in seeding, flowering & podding (R2 = 0.432, 0.218), and in maturing stage(R2 = 0.127). The regression models were set up to test the impact of four meteorological factors on soybean NDVI and analyze the quantitative relations among them, namely Partial Least Squares (PLS), Stepwise Regression and Ridge Regression. It was found that among four meteorological factors affecting soybean NDVI values, the major factors are the solar radiation and the air temperature, while the minor ones are the wind speed and humidity and their influence on soybean NDVI values can be neglected. In significance tests, predictive accuracy of the three regression models for soybean NDVI in all three growing stages are all statistically significant (P<0.01). By contrast, Ridge Regression has a slightly higher coefficient than partial least squares (PLS) and Stepwise Regression, while the latter two models have almost the same correlation. In contrast of the predictive values and the real test results of the three regression models for soybean NDVI, the Ridge Regression ranks the highest on predictive accuracy, with the Root Mean Square Error (RMSE) of 0.034˛0.018 and 0.016 and R2of 0.820, 0.908 and 0.934 in three stages of seeding, flowering & podding and maturating, followed by a less accurate predictive level of Stepwise Regression and the least accuracy of PLS. Regression model can have a better prediction of daily variation trend of soybean NDVI values and a better accuracy of NDVI monitoring. [ABSTRACT FROM AUTHOR]

A well-defined azido-poly(N-isopropylacrylamide) (PNIPA) was prepared by reversible addition-fragmentation chain transfer polymerization of NIPA and glycidyl methacrylate followed by the azidization of pendant epoxyl groups. Then the polymer was crosslinked via Click chemistry by bis- or tetra-alkynyl terminated compounds, which were synthesized through esterification of 1,3-propanediol and pentaerythritol with propiolic acid and 6-heptynoic acid, to fabricate PNIPA hydrogels. And the swelling properties of obtained hydrogels were studied as functions of crosslinker dosage and species. The results showed that the decrease of crosslinker dosage or increase of chain length thereof could enhance swelling capacities of hydrogels due to bigger free volumes within networks; the functionality of crosslinkers almost had no influence on swelling properties of hydrogels. In addition, no obvious distinction was found for lower critical solution temperature and swelling response to a temperature jump during reswelling and deswelling course, no matter what and how much crosslinker was used. [ABSTRACT FROM PUBLISHER]

Background Noninvasive prenatal testing (NIPT) by massively parallel sequencing (MPS) of the circulating cell free fetal (cff) DNA during the second trimester of pregnancy is now a frontline test for detecting common fetal chromosomal abnormalities. However, the availability of an earlier test result in the first trimester would enable better clinical management of high-risk pregnancies. The aim of the study was to determine the feasibility of early gestational NIPT. Methods Plasma DNA libraries were subjected to MPS and chromosomal read counts normalized to reference. Chromosomal aneuploidy was determined by z -scores (− 3 < z < 3, normal range). The cff DNA fraction in 96 male pregnancies was calculated by the relative proportion of Y chromosomal reads. Results NIPT results were obtained in the first (8–12 weeks) and second (15–18 weeks) trimester for 182 high-risk women. NIPT identified T21, T13 and 45,X in 3 pregnancies that were confirmed by karyotyping, but missed a T15 pregnancy that eventually miscarried. In the remaining 178 pregnancies, results for first and second trimester NIPT were normal. The median fetal fraction in the first trimester was 7.6 ± 4.18% and 15% of samples were identified with a cff fraction below 4%. Different trends of cff DNA fraction change were observed between the first and second trimester, with 59% of pregnancies showing an increase, 17% showing no change and 24% showing a decrease. Conclusions Although NIPT was highly reliable and accurate at an earlier gestational age, clinical implementation should proceed with caution due to a small, but significant, number of pregnancies associated with a low cff DNA fraction. [ABSTRACT FROM AUTHOR]

An all-solid-state, lightweight, flexible, and wearable polymer solar cell (PSC) textile with reasonable photovoltaic performance has been developed. A metal textile electrode made from micrometer-sized metal wires is used as the cathode, and the surfaces of the metal wires are dip-coated with the photoactive layers. Two ultrathin, transparent, and aligned carbon nanotube sheets that exhibit remarkable electronic and mechanical properties were coated onto the modified metal textile at both sides as the anode to produce the desired PSC textile. Because of the designed sandwich structure, the PSC textile displays the same energy conversion efficiencies regardless of which side it is irradiated from. As expected, the PSC textiles are highly flexible, and their energy conversion efficiencies varied by less than 3 % after bending for more than 200 cycles. The PSC textile shows an areal density (5.9 mgcm-2) that is lower than that of flexible filmbased PSCs (31.3 mgcm-2). [ABSTRACT FROM AUTHOR]

An all-solid-state, lightweight, flexible, and wearable polymer solar cell (PSC) textile with reasonable photovoltaic performance has been developed. A metal textile electrode made from micrometer-sized metal wires is used as the cathode, and the surfaces of the metal wires are dip-coated with the photoactive layers. Two ultrathin, transparent, and aligned carbon nanotube sheets that exhibit remarkable electronic and mechanical properties were coated onto the modified metal textile at both sides as the anode to produce the desired PSC textile. Because of the designed sandwich structure, the PSC textile displays the same energy conversion efficiencies regardless of which side it is irradiated from. As expected, the PSC textiles are highly flexible, and their energy conversion efficiencies varied by less than 3% after bending for more than 200 cycles. The PSC textile shows an areal density (5.9 mgcm-2) that is lower than that of flexible film-based PSCs (31.3 mgcm-2). [ABSTRACT FROM AUTHOR]

Novel wire‐shaped polymer solar cells that have high performance are developed by introducing a thin layer of titania nanoparticles that increases the charge separation and transport and an aligned carbon nanotube fiber electrode that increases their stability. These solar cell wires are easily woven into flexible clothes that serve as lightweight and deformable power sources for portable electronic devices. [ABSTRACT FROM AUTHOR]

Ni/In 2 O 3 was confirmed to be active for CO 2 hydrogenation to methanol. Herein, the In 2 O 3 -ZrO 2 solid solution was prepared to support the highly dispersed nickel catalyst by chemical reduction. A CO 2 conversion of 17.9% with a space-time yield (STY) of methanol of 0.63 g MeOH g cat −1 h−1 was achieved at 300 °C and 5 MPa on Ni/In 2 O 3 -ZrO 2 of 5 wt% Ni loading. The STY of methanol has a 43.2% increase, compared to Ni/In 2 O 3. The use of ZrO 2 optimizes the oxygen vacancies for CO 2 activation. The highly dispersed Ni catalyst facilitates hydrogen spillover, which improves hydrogenation ability and the formation of oxygen vacancies. [Display omitted] • The chemical reduction leads to highly dispersed Ni catalyst on In 2 O 3 -ZrO 2. • The highly dispersed Ni catalyst causes an excellent hydrogen spillover. • The use of ZrO 2 optimizes and stabilizes the oxygen vacancies for CO 2 activation. • Ni/In 2 O 3 -ZrO 2 is a highly active catalyst for CO 2 hydrogenation to methanol. • High methanol selectivity is achieved over Ni/In 2 O 3 -ZrO 2. [ABSTRACT FROM AUTHOR]

Abstract: The concise syntheses of two natural diphyllin glycosides Cleistanthin-A (CA), Cleistanthoside-A (CleA) and its derivative, Cleistanthoside-A tetraacetate (CleT), have been achieved. They were evaluated for their in vitro anti-proliferative activities against MCF-7, HeLa, HepG2, HCT-116, U251 cancer cell lines by MTT assay. Both of CA and CleT were anti-proliferative to these cancer cells at nanomolar concentrations. They have been shown to inhibit the activity of vacuolar H+-ATPase (V-ATPase) in HepG2 cells and neutralize the pH of lysosomes at nanomolar concentrations. [Copyright &y& Elsevier]

It is critically important to develop miniature energy harvesting and storage devices in modern electronics, for example, for portable and foldable electronic facilities. In this review article, novel miniature solar cells, electrochemical capacitors and lithium-ion batteries as well as their integrated devices are carefully summarized. Particular emphasis has been paid to wire-shape energy devices that exhibit unique and promising advantages such as being lightweight and weaveable compared with the conventional planar architecture. Recent new materials and attractive designs are highlighted for these wire-shaped energy devices. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we study the wave equation with sub-linearity in a ball with periodic-Dirichlet conditions. Combining the minimax principle with an approximation argument, we prove the existence of infinitely many time-periodic solutions for the problem. The proof also relies on the structure of the spectrum of the linearized problem. [Copyright &y& Elsevier]

Abstract: A series of thieno[3,2-d]pyrimidines bearing a hydroxamic acid moiety as novel HDAC inhibitors were designed and synthesized. The structures of the new synthesized compounds were confirmed using IR, 1H, 13C NMR spectrum. Compounds 11–13 showed potent inhibitory activities against HDACs with IC50 values at 0.38, 0.49 and 0.61μM. Most of target compounds displayed strong anti-proliferative activity by a MTT assay on three human cancer cell lines including HCT-116, MCF-7 and HeLa. Compound 11, having potent inhibitory activities against HDACs, induced apoptosis and G2/M cell cycle arrest in HCT-116 cell line. [Copyright &y& Elsevier]

Making sense: A novel polyacetylene composite material with incorporated aligned carbon nanotubes shows rapid changes in both fluorescent intensity and color appearance in response to applied electric currents, and these electrochromatic transitions remain reversible even after a thousand cycles. The composite material is anticipated to be suitable for various other sensing applications. [ABSTRACT FROM AUTHOR]

Es grünt so grün: Ein neuartiges Polyacetylen ‐ Kompositmaterial, das ausgerichtete Kohlenstoff ‐ Nanoröhren enthält, verändert rasch seine Fluoreszenzintensität und Farbe als Reaktion auf einen angelegten elektrischen Strom (siehe Bild). Diese elektrochromen Übergänge bleiben selbst nach tausend Zyklen reversibel. Das Kompositmaterial könnte sich für eine Reihe von Sensoranwendungen eignen. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we deal with the global existence of positive solutions for a multi-parameter system of second-order elliptic equations with respect to parameters, by using the fixed point index theory in cones, the sub-supersolutions method, Leray–Schauder degree theory and a priori estimates technique. In addition, for the computation of Leray–Schauder degree on the Cartesian product of two ordered intervals, we also establish a result about Leray–Schauder degree on a strict ordered interval induced by a pair of strict lower and upper solutions for a system of second-order elliptic equations. [Copyright &y& Elsevier]

Abstract: We obtain new results on the existence of nonzero positive weak solutions of systems of -Laplace equations under some sublinear conditions. These sublinear conditions employ the principal eigenvalues of the corresponding homogeneous Dirichlet boundary value problems involving -Laplacian operators. Our results generalize and improve some previous results on the existence of nonzero positive solutions of systems of Laplace equations and on some eigenvalue problems of systems of -Laplace equations. Applications of our results are given to systems of -Laplace equations with specific nonlinearities. [Copyright &y& Elsevier]

A new method for rapidly eliminating pathogenic microorganisms in large air space using spraying •OH radicals is presented in this paper. With a physical method of strong electric-field discharge, large numbers of •OH radicals were produced by the oxygen activated particles of O2+, O( 1D), O( 3P), etc., and the introducing reagent HO2−. The gram-positive bacteriaBacillus subtilis, the gram-negative bacteriaSerratia marcescens, andBacillusspores were used for the eliminating experiments. Results show that the different microorganisms were rapidly killed by •OH radicals with a concentration of 0.8 mg/L and spraying density of 21 μL/m2within 4 sec. Cell morphological changes were also observed under microscope. The cells ofB. subtilisandBacillusspores in their cellular wall, cellular membrane, or cell protoplasm were greatly destroyed when being exposed to a killing dosage of •OH radicals.Implications: Increasing air spread of pathogenic microorganisms has prompted serious concerns for their threat to environmental safety. However, there is no an effective method to rapidly eliminate these harmful microorganisms in large air space. In comparison with conventional disinfectants, advanced oxidation technology (AOT) based on hydroxyl radicals (•OH) has excellent advantages. The main problem of how to produce the •OH radicals with high concentration and large production is solved by a physical method of strong electric-field discharge. A new method for rapidly eliminating pathogenic microorganisms in large air space using spraying •OH radicals is described in this paper. [ABSTRACT FROM PUBLISHER]

So far there is not an effective method to prevent the rapid spread of harmful microorganisms in air space or on the surface of objects. In this paper, a physical method based on strong electric-field discharge was used to produce hydroxyl radicals (\cdot\OH) for biological decontamination and sterilization in air space. Results show that cells of Staphylococcus aureus, Escherichia coli, and Yeast were rapidly killed by the \cdot\OH fogdrops with a concentration of 0.6 mg/L and spray density of 22 \mu\L/m^2 within 4 s. Cell morphological changes were also observed through the microscope. Most of the cells were disrupted and lysed into small debris when being exposed to a killing dosage of \cdot\OH radicals. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we prove some uniqueness and convergence results for a competing system and its singular limit, and an interior measure estimate of the free boundary for the singular limit. [Copyright &y& Elsevier]