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Three new lignan glycosides, piperhancosides A−C (1 − 3), and two known compounds (4 − 5) were isolated from the n -BuOH extract of the stems of Piper hancei Maxim. The planar structures of the new compounds were elucidated by extensive spectroscopic analyses. Their relative and absolute configurations were determined by coupling constants, chemical shift differences, acid hydrolysis, enzymatic hydrolysis, and experimental ECD spectra. All the isolates were evaluated for their antineuroinflammatory and antioxidant activities, and compounds 4 and 5 showed significant DPPH.+ radical scavenging ability with EC 50 value of 14.07 and 16.48 μ M, respectively. [Display omitted] • Three new (1 − 3) and two known (4 − 5) lignan glycosides were isolated from Piper hancei. • Their structures were elucidated by spectroscopic analyses, hydrolysis, and ECD data. • Compounds 4 and 5 showed significant DPPH.+ radical scavenging abilities. [ABSTRACT FROM AUTHOR]

• Fractional exponential moments-based maximum entropy method is applied for reliability analysis. • A novel transformed mixed-degree cubature rule is proposed for fast moment assessment. • A two-step strategy is developed to rationally determine the most appropriate angle. • Numerical examples are studied to validate the effectiveness of the proposed method. Based on the maximum entropy method with fractional exponential moments, a new method is proposed for deriving the probability density function of the limit state function for reliability calculation. Since numerical evaluation of fractional exponential moments is of critical significance, a novel transformed mixed-degree cubature rule is developed. First, the integral related to fractional exponential moment evaluation is transformed over the standard normal space, where the cubature rule can be employed for the numerical evaluation. Then, the spherical and radial rules with different degrees are combined to formulate a novel mixed-degree cubature rule, where the sample size only increases linearly with the dimension. To further enhance and improve the precision, a rotational transformation is performed over the samples produced by the mixed-degree cubature rule to obtain a transformed cubature rule, in which a proper angle needs to be specified. A two-step strategy is then put forward to specify the appropriate angle in the transformed mixed-degree cubature rule, where the standard deviations of input variables and Kullback-Leibler divergence are used to formulate the objective functions. The proposed approach is verified via a set of numerical examples involving different types of problems. [ABSTRACT FROM AUTHOR]

[Display omitted] • We propose a novel decoupled Image and Frequency-domain Spatial-Spectral Framework. • The proposed module extracts multi-scale features from dual domains. • A module can transfer the advantages of convolution to the transformer. • The proposed neural network can achieve better performance. Hyperspectral image classification (HSIC) is a rapidly developing field that utilizes deep learning methods. However, the reliance on convolutional neural networks (CNNs) for spectral–spatial feature extraction presents certain limitations. Specifically, the use of the fixed-position convolutional kernels in CNNs hinders their ability to capture fully the spectral information around the spatial central pixel, thereby overlooking critical differences between features. To address this issue, a decoupled image- and frequency-domain spectral–spatial framework for HSIC was developed in this study. This method incorporates image- and frequency-domain-based multiscale learnable convolutional attention to refine the differentiating features of the different feature distributions. Additionally, a novel frequency-domain information enhancement module was designed to extract the structural shape and texture details under the semantic constraints of the frequency phase, complementing the image domain to improve the extracted feature maps. Furthermore, a simple and efficient hierarchical feature representation module was introduced to extract both local and global information effectively from the fused features. The experimental results obtained using three open datasets and a practical hyperspectral image of the Gaofen-5 satellite demonstrate that the proposed method outperforms other state-of-the-art HSIC methods. [ABSTRACT FROM AUTHOR]

Intervening in college students' environmental behavior is crucial not only to counter the increasing decline in their engagement in pro-environmental actions but also to facilitate a transition toward a more environmentally friendly lifestyle in the future. This study investigates the impact of a common policy instrument, financial incentives, in intervening to promote pro-environmental behavior among college students. Our specific focus is on how financial incentives directly influence behavior and their moderating role on three types of norms (moral norms, injunctive norms, and descriptive norms). The proposed model is empirically tested on 408 college students from four cities in China regarding their waste recycling behavior. Findings suggest that behavior is predominantly influenced by perceived behavioral control, attitude, and moral norms. Financial incentives are found to be insignificantly related to either intention or behavior and may potentially have an undermining effect on the relationship between moral norms and behavior. [ABSTRACT FROM AUTHOR]

Using first-principles calculations, we investigate the ideal shear strengths σ max of L1 2 -Ni 3 Al crystals with various multiple additions of Re and W. A correlation energy function Δ E Re A + W B (d) is adopted to evaluate the interaction between point defects (i.e., Re A and W B ). The results indicate extra addition of Re or W does not change the site preference of Re and W at Al sites, and W in preference to Re occupies Al sites. In this preferred site, σ max of L1 2 -Ni 3 Al crystals with single Re addition is larger than that with single W addition, but the strengthening effect of double Re addition is weak compared with multiple addition of Re and W. Strong repulsion is found to be disadvantageous for the reinforcement of γ′-Ni 3 Al phases, and σ max in Re A + W B complexes decreases with increasing Δ E Re A + W B (d). The analysis of electronic and geometric structures reveals Re/W-addition-induced strengthening mainly originates from stronger Re/W Ni bonding than Al Ni bonding, but a significant increase of σ max in γ′-Ni 3 Al-Re W systems is attributed to a cooperative effect of electronic interaction and local elastic strain energy, and the local elastic strain energy is dominant. Image 1 • Interaction between Re and W does not change their site preferences in Al sublattices. • W in preference to Re occupies Al sites in the case of multiple addition of Re and W. • Extra addition of Re/W can increase σ max in ternary Ni 3 Al-Re/W crystals. • Strong repulsion between Re and W is harmful to the reinforcement of γ′-Ni 3 Al phases. • Local elastic strain energy plays a key role in the detrimental impact of Re W repulsion. [ABSTRACT FROM AUTHOR]

Highlights • Laser-MIG hybrid welding of aluminum alloy with Ar-He shielding gas mixture. • Ar-He shielding gas mixture exerted great effect on physical properties of plasma. • Volume ratio of He enough for improving welding characteristics was 50%. • Effective laser power density increased with the increasing He volume ratio. • Keyhole fluctuation was suppressed while using Ar-He shielding gas mixture. Abstract During laser or laser-arc hybrid welding process of aluminum alloy, laser power waste and keyhole fluctuation are drastic due to the shielding effect of dense plasma. Consequently, small weld penetration depth and numerous weld porosity defects are produced. In the present work, Ar-He shielding gas mixture was used to improve the weld quality of fiber laser-metal inert gas (MIG) hybrid welded aluminum alloy. The influences of Ar-He shielding gas mixtures with various He volume ratios on plasma temperature, electron density, weld penetration depth and porosity defect were investigated, respectively. The He volume ratio enough for improving the weld penetration depth and suppressing the porosity defect was 50%. The effective laser power density increased with the increasing He volume ratio, which contributed to the increase of weld penetration depth. The weld porosity defects were suppressed efficiently, since the stability of the keyhole was improved while using Ar-He shielding gas mixture. [ABSTRACT FROM AUTHOR]

Atomic interactions and phase stability in Ni-rich Ni-W alloys have been investigated by using first-principles methods and statistical thermodynamic simulations. First-principles methods have been employed to explore lattice expansion, enthalpies of formation, atomic interactions, and ordering energies of ordered as well as random structures in Ni-rich Ni-W alloys with consideration of the corresponding temperature-dependent magnetic states. It is found that atomic interactions in Ni-rich Ni-W alloys depend on alloy composition, atomic volume, and magnetic state. Nevertheless, the magnetic state of Ni greatly affects the formation enthalpies, which leads to a diverse phase separation behavior at finite temperature in Ni-rich Ni-W alloys. By using atomic interactions that reproduce the ordering energies obtained in the direct total energy calculations, our statistical thermodynamic simulations of chemical short-range order results show that fcc-based ordered D1 a , D0 22 , and Pt 2 Mo phases can be observed in Ni-20 at.% W, Ni-25 at.% W, and Ni-33 at.% W alloys, respectively. Moreover, the short-range order diffuse intensity and atomic stacking for aforementioned ordered phases have been analyzed, the order–disorder transition behaviors have been also investigated in detail for the Ni-rich Ni-W alloys up to 35 at.% W with comparison of current experimental results. Both magnetic state and alloy composition have the potential to induce the formation of distinct ordered phases, offering promising avenues for designing Ni-based alloys. The methodologies we used in this study can be applied to investigate the atomic interactions as well as phase stability in other alloy systems. [Display omitted] [ABSTRACT FROM AUTHOR]

Twelve pairs of sesquineolignan enantiomers (1a / 1b − 6a / 6b and 1c / 1d − 6c / 6d), including twenty one undescribed and three known (2b , 3b , and 4b) sesquineolignans were isolated from an ethanol extract of the stems and leaves of Neoshirakia japonica (Euphorbiaceae). The successful separation of twelve pairs of enantiomers with mirror image-like electronic circular dichroism (ECD) curves and opposite specific rotation values, as one of the most important steps in compound isolation, was carried out by chiral HPLC columns. The absolute configurations of all undescribed sesquineolignans were elucidated by comprehensive analysis of their experimental ECD spectra. The effects of all the isolates on antineuroinflammatory and radical scavenging activity were evaluated. Compared with the positive control minocycline (IC 50 = 1.2 μM), compounds 1a / 1b / 1c / 1d − 6a / 6b / 6c / 6d with IC 50 values being greater than 50 μM displayed almost no effect on the inhibition of NO production in LPS-induced BV-2 microglial cells. The results of DPPH-radical scavenging activity for them showed that compound 3c had moderate radical scavenging ability (EC 50 = 48.47 μM), while the EC 50 value of positive control vitamin C was 18.21 μM. Twelve pairs of sesquineolignan enantiomers, including twenty one undescribed and three known sesquineolignans were isolated from Neoshirakia japonica. The effects of all the sesquineolignans on antineuroinflammatory and antioxidant activities were evaluated. [Display omitted] • Twelve pairs of sesquineolignan enantiomers were isolated from Neoshirakia japonica. • The separation of these enantiomers were carried out successfully by chiral HPLC columns. • The absolute configurations of all sesquineolignans were established by analysis of their ECD spectra. [ABSTRACT FROM AUTHOR]