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The paper presents a rigorous analytical approach to predicting the load–settlement behavior of axially loaded piles embedded in sandy soils, adopting the advanced SANISAND model. The problem of the soil state around the pile during loading is formulated as a system of first-order ordinary differential equations, which can be solved as an initial value problem. The derived load–settlement (t–z) curve is then implemented into the load-transfer method to determine the pile's load–settlement behavior in sands and the deformation mechanism of the soil around the pile during axial loading. To verify the proposed analytical approach, a FEM simulation is performed with a user-defined subroutine, demonstrating its capacity to capture the dilatancy behavior of sands as the pile moves downwards. Additionally, a parametric analysis is conducted to assess the influence of the initial void ratio on the stress–strain relationship of the sandy soil around the pile during the loading process. The proposed analytical approach is also compared with a well-established finite-element model and a centrifuge test. The results indicate that the present approach can well predict the elastoplastic load–settlement response of the pile and reflect important phenomena observed from pile tests. [ABSTRACT FROM AUTHOR]

AbstractThis paper presents an analytical method to study the lateral response of offshore slender piles near sandy slopes. A slope deformation model is constructed to evaluate the slope displacement induced by the load transfer of a pile at the slope crest. A modified strain wedge (SW) model is developed by considering the slope deformation and the impact of the slope on the effective overburden pressure. A geometric transformation is employed to facilitate the analysis of the edge distance. The efficiency and accuracy of the method are demonstrated through comparisons of its results with those of six centrifuge piles and four model piles. Finally, the effects of the slope angle and edge distance on the pile response are discussed. This method introduces the slope deformation into the analysis of soil-pile interaction, allowing for comprehensive consideration of the combined effects of slope angle and edge distance. [ABSTRACT FROM AUTHOR]

Soils are known to be inherently anisotropic, resulting in complex responses to loading. This paper aims to develop an elastoplastic solution for the undrained expansion of a cylindrical cavity in sands adopting a non‐associated and anisotropic model, SANISAND. The rigorous derivation of the stress‐strain state of the soil element is provided following a standardized solving procedure. The dilatancy and crushing of the soil are invoked in the three‐dimensional cavity expansion solution by adopting the critical state soil mechanics and limiting compression curve, respectively. By combining this with a governing equation that considers the undrained condition, the stress‐strain state of the surrounding soil around the cavity can be determined. A subroutine is then implemented into the ABAQUS FEM simulation to verify the solution. The solutions are also validated against those based on an isotropic model, and anisotropic sand is used to investigate the effects of the initial effective mean stress, at‐rest coefficient of earth pressure, and overconsolidation ratio on the stress distribution, stress path, and boundary surfaces. [ABSTRACT FROM AUTHOR]

Polyethylene glycol (PEG) is an artificial polymer with good biocompatibility and a low cost, which has a wide range of applications. In this study, the dynamic response of PEG single chains to different ion concentrations was investigated from a microscopic point of view based on single-molecule force spectroscopy, revealing unique interactions that go beyond the traditional sensor-design paradigm. Under low concentrations of potassium chloride, PEG single chains exhibit a gradual reduction in rigidity, while, conversely, high concentrations induce a progressive increase in rigidity. This dichotomy serves as the cornerstone for a profound understanding of PEG conformational dynamics under diverse ion environments. Capitalizing on the remarkable sensitivity of PEG single chains to ion concentration shifts, we introduce innovative sensor-design ideas. Rooted in the adaptive nature of PEG single chains, these sensor designs extend beyond the traditional applications, promising advancements in environmental monitoring, healthcare, and materials science. [ABSTRACT FROM AUTHOR]

Objective. PET (Positron Emission Tomography) inherently involves radiotracer injections and long scanning time, which raises concerns about the risk of radiation exposure and patient comfort. Reductions in radiotracer dosage and acquisition time can lower the potential risk and improve patient comfort, respectively, but both will also reduce photon counts and hence degrade the image quality. Therefore, it is of interest to improve the quality of low-dose PET images. Approach. A supervised multi-modality deep learning model, named M3S-Net, was proposed to generate standard-dose PET images (60 s per bed position) from low-dose ones (10 s per bed position) and the corresponding CT images. Specifically, we designed a multi-branch convolutional neural network with multi-self-attention mechanisms, which first extracted features from PET and CT images in two separate branches and then fused the features to generate the final generated PET images. Moreover, a novel multi-modality structure-promoting term was proposed in the loss function to learn the anatomical information contained in CT images. Main results. We conducted extensive numerical experiments on real clinical data collected from local hospitals. Compared with state-of-the-art methods, the proposed M3S-Net not only achieved higher objective metrics and better generated tumors, but also performed better in preserving edges and suppressing noise and artifacts. Significance. The experimental results of quantitative metrics and qualitative displays demonstrate that the proposed M3S-Net can generate high-quality PET images from low-dose ones, which are competable to standard-dose PET images. This is valuable in reducing PET acquisition time and has potential applications in dynamic PET imaging. [ABSTRACT FROM AUTHOR]

Objective: To develop and independently externally validate robust prognostic imaging biomarkers distilled from PET images using deep learning techniques for precise survival prediction in patients with diffuse large B cell lymphoma (DLBCL). Methods: A total of 684 DLBCL patients from three independent medical centers were included in this retrospective study. Deep learning scores (DLS) were generated from PET images using deep convolutional neural network architecture known as VGG19 and DenseNet121. These DLSs were utilized to predict progression-free survival (PFS) and overall survival (OS). Furthermore, multiparametric models were designed based on results from the Cox proportional hazards model and assessed through calibration curves, concordance index (C-index), and decision curve analysis (DCA) in the training and validation cohorts. Results: The DLSPFS and DLSOS exhibited significant associations with PFS and OS, respectively (P<0.05) in the training and validation cohorts. The multiparametric models that incorporated DLSs demonstrated superior efficacy in predicting PFS (C-index: 0.866) and OS (C-index: 0.835) compared to competing models in training cohorts. In external validation cohorts, the C-indices for PFS and OS were 0.760 and. 0.770 and 0.748 and 0.766, respectively, indicating the reliable validity of the multiparametric models. The calibration curves displayed good consistency, and the decision curve analysis (DCA) confirmed that the multiparametric models offered more net clinical benefits. Conclusions: The DLSs were identified as robust prognostic imaging biomarkers for survival in DLBCL patients. Moreover, the multiparametric models developed in this study exhibited promising potential in accurately stratifying patients based on their survival risk. [ABSTRACT FROM AUTHOR]

• This paper presents a drained expansion solution of a cylindrical cavity with fabric change effect in the sand. • The problem is formulated as a system of first-order differential equations with the known variables. • A user-defined SANISAND model is implemented as a subroutine, which is applied to FEM simulation. Sandy soil exhibits inherently anisotropy due to its microstructure, also known as 'fabric'. However, the drastic change in fabric observed during the dilatant phase is often overlooked in current cavity expansion research. This paper presents a drained expansion solution of a cylindrical cavity with fabric change effect in the sand using a simple non-associated and anisotropic model, SANISAND. The problem is formulated as a set of first-order differential equations with the unknown variables as functions of an auxiliary coordinate, which can be solved as an initial value problem. A subroutine is implemented into the FEM simulation to verify the proposed method. Additionally, cavity expansion solutions in sand are compared with those based on state-dependent dilatancy. The anisotropic fabric of the sand is studied to investigate the impact of the initial void ratio, initial mean stress, and at-rest coefficient on the void ratio path, stress distributions and paths, and bounding surfaces. The proposed solution provides a framework for the potential use of cavity expansion in sand, considering the fabric change effect, and a benchmark for further developments and numerical calculations by using the SANISAND model. [ABSTRACT FROM AUTHOR]

The response of laterally loaded piles installed near the crest of clay slopes is analysed. Three-dimensional finite element analyses are presented for piles at various distances from a slope crest and for different pile shape. The results of these analyses are used to study the variation of the pile displacement, the bending moment of the pile and the soil resistance in relation to pile to slope distance and pile shape. The obtained results show that the proximity of slope significantly affects the lateral load capacity of the piles but not significantly when the piles are placed at 7D (where D is pile diameter) or greater from the slope crest. Furthermore, the lateral soil resistance on the ground surface for circular piles is larger than that for rectangular piles at the same lateral load in level ground. The decrease rate of lateral soil resistance on the ground surface for circular piles gets faster as the slope ratio and load level increase. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the prognostic value of PET radiomics feature in the prognosis of patients with primary gastrointestinal diffuse large B cell lymphoma (PGI-DLBCL) treated with R-CHOP-like regimen.Methods: A total of 140 PGI-DLBCL patients who underwent pre-therapy [18F] FDG PET/CT were enrolled in this retrospective analysis. PET radiomics features obtained from patients in the training cohort were subjected to three machine learning methods and Pearson's correlation test for feature selection. Support vector machine (SVM) was used to build a radiomics signature classifier associated with progression-free survival (PFS) and overall survival (OS). A multivariate Cox proportional hazards regression model was established to predict survival outcomes.Results: A total of 1421 PET radiomics features were extracted and reduced to 5 features to build a radiomics signature which was significantly associated with PFS and OS (p < 0.05). The combined model incorporating radiomics signatures, metabolic metrics, and clinical risk factors showed high C-indices in both the training (PFS: 0.825, OS: 0.834) and validation sets (PFS: 0.831, OS: 0.877). Decision curve analysis (DCA) demonstrated that the combined models achieved the most net benefit across a wider reasonable range of threshold probabilities for predicting PFS and OS.Conclusion: The newly developed radiomics signatures obtained by the ensemble strategy were independent predictors of PFS and OS for PGI-DLBCL patients. Moreover, the combined model with clinical and metabolic factors was able to predict patient prognosis and may enable personalized treatment decision-making.Key Points: • Radiomics signatures generated from the optimal radiomics feature set from the [18F]FDG PET images can predict the survival of PGI-DLBCL patients. • The optimal radiomics feature set is constructed by integrating the feature selection outputs of LASSO, RF, Xgboost, and PC methods. • Combined models incorporating radiomics signatures from18F-FDG PET images, metabolic parameters, and clinical factors outperformed clinical models, and NCCN-IPI. [ABSTRACT FROM AUTHOR]

An image-based gradation calculation method considering crushed stone morphology is proposed in this paper. Eight kinds of crushed stones are prepared to figure out the effect of the particle shape on the gradation. All particles are pictured, and the photos are processed to obtain particle shape indices by using the image-based method. A minimum Feret diameter analysis method is used, which can reflect the influence of the particle shape. Then, the paper proposes a developed overall regularity to describe the morphology of particles, which is calculated by the weight of three shape indices: aspect ratio, convexity, and sphericity. The developed overall regularity is applied on gradation curve equations to provide an image-based gradation calculation method. And the provided method is validated to well fit the actual case. Furthermore, the method is also applied on two examples of gradation designation and the result proves to be feasible and practicable. [ABSTRACT FROM AUTHOR]

Purpose: To develop and externally validate models incorporating a PET radiomics signature (R-signature) obtained by the cross-combination method for predicting the survival of patients with diffuse large B-cell lymphoma (DLBCL). Methods: A total of 383 patients with DLBCL from two medical centres between 2011 and 2019 were included. The cross-combination method was used on three types of PET radiomics features from the training cohort to generate 49 feature selection-classification candidates based on 7 different machine learning models. The R-signature was then built by selecting the optimal candidates based on their progression-free survival (PFS) and overall survival (OS). Cox regression analysis was used to develop the survival prediction models. The calibration, discrimination, and clinical utility of the models were assessed and externally validated. Results: The R-signatures determined by 12 and 31 radiomics features were significantly associated with PFS and OS, respectively (P<0.05). The combined models that incorporated R-signatures, metabolic metrics, and clinical risk factors exhibited significant prognostic superiority over the clinical models, PET-based models, and the National Comprehensive Cancer Network International Prognostic Index in terms of both PFS (C-index: 0.801 vs. 0.732 vs. 0.785 vs. 0.720, respectively) and OS (C-index: 0.807 vs. 0.740 vs. 0.773 vs. 0.726, respectively). For external validation, the C-indices were 0.758 vs. 0.621 vs. 0.732 vs. 0.673 and 0.794 vs. 0.696 vs. 0.781 vs. 0.708 in the PFS and OS analyses, respectively. The calibration curves showed good consistency, and the decision curve analysis supported the clinical utility of the combined model. Conclusion: The R-signature could be used as a survival predictor for DLBCL, and its combination with clinical factors may allow for accurate risk stratification. [ABSTRACT FROM AUTHOR]

Objectives: To demonstrate the effectiveness of automatic segmentation of diffuse large B-cell lymphoma (DLBCL) in 3D FDG-PET scans using a deep learning approach and validate its value in prognosis in an external validation cohort. Methods: Two PET datasets were retrospectively analysed: 297 patients from a local centre for training and 117 patients from an external centre for validation. A 3D U-Net architecture was trained on patches randomly sampled within the PET images. Segmentation performance was evaluated by six metrics, including the Dice similarity coefficient (DSC), Jaccard similarity coefficient (JSC), sensitivity (Se), positive predictive value (PPV), Hausdorff distance 95 (HD 95), and average symmetric surface distance (ASSD). Finally, the prognostic value of predictive total metabolic tumour volume (pTMTV) was validated in real clinical applications. Results: The mean DSC, JSC, Se, PPV, HD 95, and ASSD (with standard deviation) for the validation cohort were 0.78 ± 0.25, 0.69 ± 0.26, 0.81 ± 0.27, 0.82 ± 0.25, 24.58 ± 35.18, and 4.46 ± 8.92, respectively. The mean ground truth TMTV (gtTMTV) and pTMTV were 276.6 ± 393.5 cm3 and 301.9 ± 510.5 cm3 in the validation cohort, respectively. Perfect homogeneity in the Bland–Altman analysis and a strong positive correlation in the linear regression analysis (R2 linear = 0.874, p < 0.001) were demonstrated between gtTMTV and pTMTV. pTMTV (≥ 201.2 cm3) (PFS: HR = 3.097, p = 0.001; OS: HR = 6.601, p < 0.001) was shown to be an independent factor of PFS and OS. Conclusions: The FCN model with a U-Net architecture can accurately segment lymphoma lesions and allow fully automatic assessment of TMTV on PET scans for DLBCL patients. Furthermore, pTMTV is an independent prognostic factor of survival in DLBCL patients. Key Points: •The segmentation model based on a U-Net architecture shows high performance in the segmentation of DLBCL patients on FDG-PET images. •The proposed method can provide quantitative information as a predictive TMTV for predicting the prognosis of DLBCL patients. [ABSTRACT FROM AUTHOR]

In this study, sea surface wind speed was retrieved using the Global Precipitation Measurement (GPM) dual-frequency precipitation radar (DPR) Ka-band data. In order to establish the Ka-band model at low incidence angles, the dependence of the DPR Ka-band normalized radar cross section (NRCS) on the wind speed, incidence angle, sea surface temperature (SST), significant wave height (SWH), and sea surface current speed (CSPD) was analyzed first. We confirmed that the normalized radar cross section depends on the wind speed, incidence angle, and SST. Second, an empirical model at low incidence angles was established. This model links the Ka-band NRCS to the incidence angle, wind speed, and SST. Additionally, the wind speed was retrieved by the model and was validated via the GPM Microwave Imager (GMI) wind product. The validation yielded a root mean square error (RMSE) of 1.45 m/s and the RMSE was better at a lower incidence angle and a higher SST. This model may expand the use of GPM DPR data in enriching the sea surface wind speed data set. It is also helpful for other Ka-band spaceborne radars at low incidence angles to measure wind speed in the future. [ABSTRACT FROM AUTHOR]

Rigid piles are prevalent in offshore engineering, and the utilization of the failure envelope approach in foundation design is a burgeoning trend. Nevertheless, in contrast to shallow and skirted foundations, the exploration on the failure envelope for deep-embedded foundations remains comparatively scant. Notably, among the existing failure envelopes for rigid piles, scant attention is paid to the soil strength gradient, which is a pervasive aspect of self-weight consolidated seabed. Therefore, this study endeavors to develop a failure envelope for offshore rigid piles under combined horizontal-moment loading in clay with linearly increasing undrained shear strength. This endeavor is achieved by employing an inclined ellipse framework and separately deriving the characteristic parameters against corresponding failure mechanisms. Subsequently, validation against FELA cases and tests reveals that the proposed equations effectively capture the essential characteristics of the failure envelope and offer fair predictions in terms of bearing capacity. Furthermore, comparative analyses with previous solutions underscores the superiority of the proposed method in scenarios involving rigid piles and linearly increasing soil strength profiles. Additionally, a parametric analysis demonstrates that as the soil strength gradient intensifies, the long axis of the failure envelope presents a notable expansion, emphasizing the imperative of incorporating the soil strength gradient in practical design considerations. • A failure envelope for offshore rigid piles under combined horizontal-moment loading in clay is developed. • The proposed equations can generally capture the main features of the failure envelope. • The proposed method possesses superiority in cases of rigid piles and linearly increasing soil strength profiles. [ABSTRACT FROM AUTHOR]

A modified strain wedge model for analyzing the lateral response of reinforced concrete piles in sand is proposed in this paper. To address the limitations of the strain wedge model, the relationship between the lateral displacement of the pile and the soil strain is modified. This modification comprehensively considers the effects of the global compression of the soil and the local angle of the pile on the soil strain. The validity and accuracy of the proposed model are verified by published centrifuge test results and field test results. Finally, the effects of pile materials, pile geometry, and pile head boundary conditions on the lateral response of reinforced concrete piles in sand are discussed. • A modified SW model is proposed to analyze the plasticity development of RC piles subjected to lateral load in sand. • The model modifies the relationship between pile displacement and soil strain using layer-by-layer area equivalence. • The effects of material, geometry and boundary of piles on the plastic behavior of RC piles are discussed using this model. [ABSTRACT FROM AUTHOR]

Revealing lateral soil bearing mechanism around an offshore monopile is critical for understanding and solving soil-pile interactions. In this paper, the lateral bearing mechanism around an offshore monopile in sand is analyzed and a corresponding analytical method is established. Three soil bearing mechanisms, including wedge-type flow, triaxial extension and volume compression, near mudline under working load level are proposed by analyzing the distribution of the Lode's angle (θ L) and soil displacement vectors. A corresponding analytical method to calculate the lateral response of the monopile is developed based on the strain wedge (SW) model. The proposed model is verified through three pile tests. Finally, the effect of the parameters of Duncan-Chang model on the monopiles in dry and saturated sand is discussed. • Wedge-type flow, triaxial extension, and volume compression around a laterally loaded monopole are clarified. • The reasons for the formation of the three soil bearing mechanisms are explained. • A simplified analytical method considering the three soil bearing mechanisms is established to calculate monopile behaviors. • The clarification of the soil bearing mechanisms is useful for understanding and solving soil-pile interactions. [ABSTRACT FROM AUTHOR]

Piles are inevitably installed on sloping coastlines or inclined seabeds to support offshore wind turbines, offshore bridges, and other structures. The objective of this paper is to develop an analytical method for investigating the lateral response of short piles near clay slopes. The soil-pile interaction is modelled by a two-spring model which is used to describe the soil resistance around the pile and the horizontal shear force at the pile base. Considering the combined effect of slope angle and near-slope distance, the ultimate soil resistance along the pile is divided into three cases based on the nearby soil flow mechanism. The soil-pile-slope surface deformation mechanism is established according to the rotational deformation characteristics of short piles. In contrast to the modification of the initial stiffness, the p-y curve around the pile is constructed by considering the deformation mechanism. The accuracy of the analytical method is verified by comparing its results with two piles on level ground and five piles near slopes. Considering the soil-pile-slope deformation mechanism, the secant stiffness of the p-y curve is automatically adjusted and reduced without the need for additional numerical simulations or pile tests to determine the reduction factor of the initial stiffness. • A method is proposed for the analysis of laterally loaded short piles near clay slopes. • The method considers both the soil flow mechanism and the slope surface deformation mechanism. • The slope surface deformation mechanism is introduced into the framework of the p-y curve. • The framework automatically adjusts and reduces the secant stiffness of the p-y curve. [ABSTRACT FROM AUTHOR]

[Display omitted] • Anisotropic FCG of SLM AISI 420 in two build directions was studied. • FCG resistance is greater for loading direction parallel to the build direction. • FCGR difference between two build directions decreased after post-tempering. • Elongated cellular structure dominated anisotropy of FCG behavior. • Tempered martensite had greater effects on FCGR of perpendicular direction. This study investigated the fatigue crack growth (FCG) behavior of selectively laser-melted AISI 420 martensitic stainless steel built in two directions. The effect of tempering treatment at 400 °C was considered. In both as-built and tempered conditions, the parallel orientation exhibited lower fatigue crack growth rates (FCGRs) than the perpendicular orientation, indicating an anisotropic FCG behavior. Tempering treatment moderately reduced the anisotropy of FCG behavior, as the difference in FCGR between the two build orientations decreased in the tempered state. The anisotropic FCG behavior was attributed to the interaction between the crack path and the elongated cellular structure. Tempered martensite had a greater influence on the FCGR of the perpendicular group over the parallel group in tempered state. [ABSTRACT FROM AUTHOR]

Indium droplets were grown on GaAs (001) substrates by droplet epitaxy method. The samples grown at different temperatures were characterized by atomic force microscope (AFM), and the surface morphology was observed. The study illustrates that indium droplets are very sensitive to the substrate temperature. The droplet density decreases with the increase of the substrate temperature, and its size increases with the increase of the substrate temperature. The physical mechanism of indium droplet formation at different substrate temperatures was analyzed, and the reason was explained. According to the relationship between the maximal cluster density and substrate temperature in nucleation theory, the functional relationship between the density of indium droplets and the substrate temperature is calculated as nx =5.17 exp(0.69 eV/kT). [ABSTRACT FROM AUTHOR]

A concave slope is a common type of slope. This paper proposes a simplified method to study the effect of a clay concave slope on laterally loaded piles. The hyperbolic p - y curve model is selected as the lateral pile-soil interaction model of the concave slope. Considering the two angles of the concave slope, the variation of the ultimate soil resistance with depth is divided into two parts, and the ultimate soil resistance varies nonlinearly with depth. The reduction factor method and normalization method are used to obtain the initial stiffness. The theoretical results will be compared with the calculation results of the 3D FE analysis to prove the rationality of this method. Finally, the simplified method is used to analyze the response of laterally loaded piles under different parameters. [ABSTRACT FROM AUTHOR]

A unified description of finite nuclei and equation of state of neutron stars presents both a major challenge and also opportunities for understanding nuclear interactions. Inspired by the Lee–Huang–Yang formula of hard-sphere gases, we develop effective nuclear interactions with an additional high-order density dependent term. While the original Skyrme force SLy4 is widely used in studies of neutron stars, there are not satisfactory global descriptions of finite nuclei. The refitted SLy4' force can improve descriptions of finite nuclei but slightly reduces the radius of neutron star of 1.4M⊙ with M⊙ being the solar mass. We find that the extended SLy4 force with a higher-order density dependence can properly describe properties of both finite nuclei and GW170817 binary neutron stars, including the mass-radius relation and the tidal deformability. This demonstrates the essential role of high-order density dependence at ultrahigh densities. Our work provides a unified and predictive model for neutron stars, as well as new insights for the future development of effective interactions. [ABSTRACT FROM AUTHOR]

This paper proposed a method for analysis of a drilled pile under vertical load at the crest of rock slope. Based on wedge theory, a modified model of normal stiffness of socket wall affected by the slope is obtained. Analyze the shear behaviors of the pile-rock interface, an analytical solution of load transfer of pile at the crest of rock slope is obtained. To evaluate the accuracy of the new method, this method is compared with the results of finite difference analysis. Finally, the method is used to analyze the effect of slope, pile, and rock properties on the unit side resistance and axial force. [ABSTRACT FROM AUTHOR]

Serving as one of the largest rivers in terms of both sediment and organic carbon transport fluxes in the world, the Yellow River plays a crucial role in regional biogeochemical process as well as in the global carbon cycle. However, although a large number of studies have been carried out on the flux, composition, source and seasonal variation of total particulate organic carbon in the Yellow River so far, studies on molecular biomarkers at different spatial and temporal scales are still scarce. In this study, we focus on the molecular and hydrogen isotopic properties of leaf wax n-alkanes among different types of samples which obtained from different seasons (flood vs. non-flood) along the lower Yellow River. The molecular distribution of n-alkanes show that the riparian topsoils are subject to inputs from the overlying vegetation, while the suspended sediments from the flood season are characterized by the mixing of soil materials which originate from various stratigraphy with different ages on the Chinese Loess Plateau. Due to the contrasting hydrodynamic conditions, the n-alkanes in suspended sediments also show distinct molecular composition between flood and non-flood seasons. Additionally, considering the effect of climatic factors, the proportion of monocots in flood-season suspended sediments is calculated from a semi-quantitative perspective using δ2Hwax. Our findings may bring to light new considerations for the interpretation of leaf wax proxies in studies of organic matter sources of Yellow River. [ABSTRACT FROM AUTHOR]

Integrating the merits of different components to construct heterostructures for energy storage and conversion has attracted intensive attention. Herein, taking advantage of bimetallic MOFs and transition bimetal hydroxide, we have successfully used nanoflower-like Ni1−xCox(OH)2 as both the precursor and template to in situ construct three dimensional (3D) NiCo-MOF@Ni1−xCox(OH)2 (denoted as MOF@TMH) hierarchical heterostructures. Benefiting from the optimized composition with hierarchical heterostructures assembled by ultrathin nanosheets, MOF@TMH-2 possesses rich effective active sites and high electrochemical reactivity, delivering superior pseudocapacitor performance with a specific capacitance of 1855.3 F g−1 at 2 A g−1 and good rate performance. Besides, MOF@TMH-2 also exhibits excellent OER activity with small overpotentials of 193 mV and 310 mV at 10 and 100 mA cm−2, respectively. [ABSTRACT FROM AUTHOR]

Background: Bleeding control as one of the major challenges in laparoscopic pancreaticoduodenectomy (LPD) necessitates a considerable anatomical knowledge of the blood supply to the pancreatic head so as to improve the safety of this surgery. This study aimed towards a better understanding of the anatomical features of the dorsal pancreatic artery (DPA), as well as its clinical significance in LPD. Method: Thirteen Chinese cadaveric specimens were used to study the blood supply of the pancreatic head. Twelve of them were perfused with latex, and the other fresh one was used to build the intraorganic structure model of the pancreas by mold casting. Between July 2018 and June 2019, a total of thirty-five consecutive patients without vascular encasement, who underwent LPD in our institute, were performed with computed tomography as a preoperative detection of the DPA. The DPA was ligated prior to uncinate process dissection in seventeen patients ("early DPA ligation" group), as the others were assigned into the control group. Results: In the thirteen cadaveric specimens, the DPA originates, respectively, from the splenic artery (46.1%), superior mesenteric artery (38.5%), common hepatic artery (7.7%) and right gastroepiploic artery (7.7%). The right branch of the DPA gives off terminal arteries to form an "inner ring" in the pancreatic head, which communicates with the pancreaticoduodenal arterial arches by plenty of collateral arteries. As compared to the control group, the "early DPA ligation" group showed a significantly lower mean blood loss (218 ± 111 vs 320 ± 162, P = 0.038), as well as shorter mean resection time (121 ± 23 vs 136 ± 22, P = 0.049). Conclusion: The DPA is one of the major blood supplies to the pancreatic head. A ligation of DPA prior to dissection of the uncinate process can help to completely block the blood supply to the pancreatic head, and therefore improve surgical outcome and safety in LPD. [ABSTRACT FROM AUTHOR]

This study proposes a nonlinear analytical method to predict the response of combined loaded offshore rigid monopiles near sandy slopes. Considering the slope effect, the method discusses the ultimate soil resistance before and behind the pile separately. The method assumes that the subgrade reaction modulus varies nonlinearly with relative density but linearly with depth. The equilibrium equation for the pile-soil system is obtained from the balance of forces and moments. By analyzing four mechanical models of rigid monopiles under combined loading and selecting three of them as the basis, a failure mode determination method is provided. The accuracy of this method is verified by comparing with indoor model test, 3D FEA model test and centrifugal test. [ABSTRACT FROM AUTHOR]

In this paper, a systematic study of the soil – pile interaction of a laterally loaded pile in proximity to undrained clay slope is conducted. The emphasis is on a modified actual displacement of the induced soil resistance in the p – y curve criterion by considering the displacement of the slope surface. On the above basic, the effect of slope on the ultimate soil resistance is also considered. A new p – y curve criterion, which divides the p – y curves in front of the pile into three cases, is proposed. Finally, the accuracy of the new model is verified through a pile test and two hyperbolic p - y curve criterions. The new criterion not only automatically reduces the stiffness of the p - y curve, but also reasonably reveals the effect of slope on the soil-pile interaction. [ABSTRACT FROM AUTHOR]

• This paper presents an analytical approach for predicting laterally loaded pile-soil interaction in saturated soils. • The soil deformation mechanism around the pile is determined using the constitutive model, MCC. • The p-y curve is derived by considering axisymmetric condition, equilibrium equation, and boundary conditions. This paper proposes an application of the cavity expansion theory to predict the load-displacement response of monotonically laterally loaded piles and the effective stress distribution of saturated modified Cam-clay (MCC) soil surrounding the pile. This approach incorporates geometric relationship, equilibrium equation, and boundary conditions to derive governing equations. These equations are subsequently solved to obtain monotonic p-y curves, which encompass the elastic, elastoplastic, and critical processes. To determine the load-displacement behavior and effective stress distribution of the soil, the proposed approach combines the deflection equilibrium differential equation with the finite-difference method. The accuracy and effectiveness of the approach are validated through a comparison with a Finite Element Method (FEM) simulation. Parametric studies are also presented to investigate the effects of overconsolidation ratio, in-situ coefficient, and mean effective stress. The validity and capacity of the proposed model are further demonstrated using model pile tests. The results affirm that this approach can well predict the monotonic load-displacement response of the pile and effectively captures important phenomena observed in pile tests. [ABSTRACT FROM AUTHOR]

In actual pile engineering, the laterally loaded offshore pile built near slope is not embedded in uniform clay or sand seabed, but layered soil seabed of different types and properties. For this purpose, a method is proposed to solve the lateral characteristics of offshore pile installed near layered slope in this paper. Based on the interaction force between layered interfaces and the concept of equivalent depth, an equivalent failure wedge model is constructed to evaluate the ultimate soil resistance of each layer of soil. It is assumed that the horizontal subgrade reaction modulus of sand in each layer changes nonlinearly with depth, while the horizontal subgrade reaction modulus of clay in each layer remains unchanged. And the influence of pile diameter and slope effect on the horizontal subgrade reaction modulus is considered. The results obtained in this paper are compared with the field test results and FE results, and the accuracy of the proposed method is verified. The analysis shows that the smaller diameter has the greater impact on the lateral deflection of pile head under the same growth range of diameter. When the pile diameter changes from 1 D to 1.5 D , the lateral deflection of pile head decreases by 42%. • A method is provided to solve the lateral behavior of offshore pile installed near layered slope with different soil properties. • Based on the concept of equivalent wedge, the failure wedge model is improved and extended to the layered soil to calculate the ultimate soil resistance by considering the layered characteristics of soil, the interaction force of the layered interface and the continuity of soil reaction. • The influence of pile diameter and slope effect on the horizontal subgrade reaction modulus is considered. [ABSTRACT FROM AUTHOR]

A cyclic p − y curve model is proposed to study the lateral response of piles in sand under two-way cyclic loads such as wind and wave. The collapse and densification of the soil around the pile caused by the repeated formation of the gap between the pile and soil during the cyclic loading are considered in the proposed model. Based on the nonlinear strain wedge model, the cyclic p − y curve is preliminarily constructed considering the friction characteristics. A collapse and recompression model of sand is established to account for the variation of the relative density of the caved soil and the characteristics of the pile-soil gap. The densification of sand caused by recompression is evaluated using the stiffness hardening index model. The cyclic p − y curve is modified by considering the collapse and densification of sand and its rationality is verified by comparing the results of calculation and centrifugal model test. Furthermore, the strengthening by the caved soil, the characteristics of the cyclic p − y curve, and the soil resistance are analyzed. • A cyclic p-y model considering the collapse and densification of sand is proposed to study the two-way response of piles. • A collapse and recompression model of sand is constructed to describe the influence of the caved soil. • The cyclic p-y curve model is modified by combining the collapse model and the densification model. [ABSTRACT FROM AUTHOR]

• The paper presents an analytical method for predicting the soil-structure interaction of axially loaded piles in sands incorporating the two-surface plasticity model. • 2-D stress–strain state of the soil-structure interface and the shear band is figured out, and 3-D elastoplastic behavior of soil around the shear band is determined. • A FEM simulation is performed with a user-defined subroutine and parametric study of the initial void ratio is conducted. The paper proposed a novel and practical analytical method for predicting the soil-structure interaction in sands. To well capture the stress softening and soil dilatancy behaviors during loading, a developed two-surface plasticity model for interface shearing is adopted to determine the 2-D stress–strain state of the soil-structure interface and the shear band, while the 3-D elastoplastic behavior of soil around the shear band is determined by another developed two-surface plasticity model for triaxial compression. Following a standardized solving procedure, the rigorous derivation for the stress–strain relationship in plastic zone is formulated as a system of first-order differential equations, which are solved as an initial value problem. Combined with the finite difference method (FDM), the load–displacement response of the axially loaded pile and the stress–strain state around the pile are presented. To verify the proposed analytical approach, a FEM simulation is performed using a user-defined subroutine. The soil with different initial void ratios ranging from very dense to loose is also modeled to demonstrate the effect of the initial void ratio on soil-structure response. The proposed analytical approach is also validated against centrifuge tests and field tests, manifesting the validity and capability of the proposed method. [ABSTRACT FROM AUTHOR]

This study gives two new analytical solutions to the tunnel by high-pressure water in the cavern. Firstly, it deals with the analytical solution for the seepage inflow in unsupported karst aquifer tunnels considering the boundary condition. Secondly, it focuses on the study of the seepage force and gives the reduction coefficient of lining water pressure. A comparison of the analytical solution and the finite element software shows a curve relationship as the relevant permeability coefficient β increases. The results show that the analytical solution and numerical solution are consistent. As d increases, β decreases gradually. β increases as r w increases or the grouting circle and initial support become thinner or the secondary lining becomes thicker. In summary, the analytical solution of β can be used to predict the seepage inflow and the seepage force of the actual engineering. [ABSTRACT FROM AUTHOR]

• A CoO/Co/TiO 2 was prepared and used in photothermal CO 2 hydrogenation to CH 3 OH. • The CoO semiconductor film was formed with a thickness of 5–6 nm from air oxidation. • Co0 species are stable at the interface of Co NPs with TiO 2. • A Z scheme mechanism was proposed for CH 3 OH formation with 39.6 μmol g cat –1 h–1. Catalytic conversion of CO 2 into methanol is of particular interest as it does not only provide valuable methanol, but also utilize the waste CO 2. In the present work, a CoO/Co/TiO 2 catalyst was developed and utilized in catalyzing CO 2 to methanol under photothermal conditions. From the results of characterization, the supported Co nanoparticles (NPs) were composed of Co0 in the bulk, CoO film formed from air oxidation on the surface, and Co0 at Co NPs-TiO 2 interfaces. This structure provided the possibility for a Z scheme photothermal catalytic system, which revealed a high activity for methanol formation in aqueous media under atmosphere pressure. It was proposed that the light excited electrons from the valence band (VB) of TiO 2 , and the excited electrons could enhance the Co0 catalytic activity under thermal conditions. The present approach will offer a new strategy to design Co based Z scheme catalysts and further improve the conversion efficiency from CO 2 to fuels. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) finite element analysis is used to investigate the vertical and horizontal bearing capacity of internal skirted foundations in normally consolidated uniform clay under undrained condition. The vertical and horizontal bearing capacity analysis has taken the effects of embedment ratio, foundation–soil interface roughness and soil strength heterogeneity into account. In this paper, new equations have been proposed for calculating vertical and horizontal bearing capacities based on the results of the finite element analyses. In the proposed equations, the vertical capacity consists of an end-bear resistance and a skin friction resistance, whereas the horizontal capacity consists of a normal resistance, a radial shear resistance and a base shear resistance. By comparing the numerical results, it shows that the proposed equations properly predicted the bearing capacities of the internal skirted foundations in uniform or non-uniform clay under undrained condition. [ABSTRACT FROM AUTHOR]

This article addresses single machine resource allocation scheduling problems with learning effects, where learning effects mean job-dependent position-based learning effects. For the common due-date assignment (CON) and slack due-date assignment (SLK) methods, a bi-cost analysis of the scheduling cost and the total weighted resource consumption cost is provided. The objective is to determine the optimal job sequence and the resource allocation simultaneously, such that the scheduling cost (the total weighted resource consumption cost) is minimized subject to the total weighted resource consumption cost (the scheduling cost) being limited. Solution procedures are provided for the problems under consideration. [ABSTRACT FROM AUTHOR]

This article addresses proportionate flowshop scheduling problems with position-dependent weights wherein the weight is not related to the job but to the position in which the job is scheduled. Common and slack due date assignment models are discussed under a due date assignment framework. The goal is to determine a feasible schedule for all jobs and due dates of all jobs to minimize a total cost function wherein the objective function is of the minsum type. Optimal properties for the problems are proposed, based on which polynomial time algorithms are provided to solve these two problems optimally. [ABSTRACT FROM AUTHOR]

Ecological restoration efforts to combat soil loss often fail to deliver the expected benefits despite enormous investments. Better understanding the close relationships between climate, vegetation, and non-linear ecosystem dynamics can help restoration activities meet their intended goals. The severely eroded Loess Plateau (LP) was selected for a case study to investigate the underlying drivers of soil retention change and their non-linear constraint impacts. The soil retention function was substantially enhanced during 2000–2015, while the water yield function was weakened. Both the favourable changes in climate conditions (i.e., increasing precipitation and declining evapotranspiration) and governmental policies for soil and water conservation and ecological restoration promoted vegetation restoration and expansion, thereby strengthening the soil retention function. Consequently, water and sediment yields declined significantly. The relationship between water yield and soil retention is non-linear and shows that the two ecosystem functions can be either in synergy or in trade-off according to the level of vegetation cover. We observed that the vegetation cover had an upper threshold (i.e., 50%) for controlling the soil erosion because of the limited water condition (rainfall), which implies that the effect of vegetation on reducing the water erosion reached its maximum capacity when the plant cover was 50%. Considering the limited water conditions in drylands, to minimize the trade-off between the water yield and soil retention and to maximize the effectiveness of ecological restoration programs, it is recommended that the overall vegetation cover in the LP be controlled at approximately 30–40%, i.e., without exceeding 50%. Currently, the non-linear constraint effects of the water condition and vegetation cover on the soil retention are yet to be thoroughly understood. Moreover, practical policy recommendations require further field-based observations and experimental studies. • The soil retention function change during 2000–2015 was assessed. • The non-linear boundary of limited water resources was investigated. • The ecological restoration strategies in degraded drylands were discussed. [ABSTRACT FROM AUTHOR]

The paper proposes a rigorous analytical approach to predict interaction between torsionally loaded piles and saturated clay soils. The soil deformation mechanism around the pile is determined using the non-associated and anisotropic constitutive model, SANICLAY, along with the axisymmetric condition, equilibrium equation, and boundary conditions. By solving the derived governing equations, the hoop shear stress against rotation curve is obtained, including elastic, elastoplastic, and critical state processes. Taking advantage of the finite-difference method, the torque-rotation behavior of the pile and the stress-strain state of the soil around the pile are figured out. The proposed approach is compared with a FEM simulation and a parametric analysis is conducted to investigate the effect of overconsolidation ratio and in-situ coefficient. Model pile tests and field tests are used to manifest the validity and capacity of the model. The results demonstrate that the present approach can well predict the torque-rotation response of the pile and can reflect some important phenomena observed in pile tests. • This paper presents an approach for predicting soil-pile interaction of torsionally loaded piles in saturated soils. • The soil mechanism around the pile is determined using the non-associated and anisotropic constitutive model, SANICLAY. • The stress-rotation curve is derived by considering axisymmetric condition, equilibrium equation, and boundary conditions. [ABSTRACT FROM AUTHOR]

This paper proposes an analytical model for calculating the lateral response of piles in homogeneous sand by considering inhomogeneous disturbance characteristics distribution. The disturbed soil in front of the pile is separated into strain wedge (SW) model elements, with the characteristics of each element calculated through coordinated pile-soil deformation. The limit of the stress level of the SW model element is also considered, and two geometric characteristic distributions are provided. A hyperbolic model is used to calculate the shear stress on the pile side. The proposed model is verified through four pile tests, and the accuracy of the new model is demonstrated by comparison. Additionally, the distributions of soil strain, stress level, fan angle and three critical depths are discussed. The results demonstrate that the model can realistically reveal the inhomogeneous stress–strain status distribution and geometric characteristics of the disturbed soil. [ABSTRACT FROM AUTHOR]

Bored piles constructed in permafrost regions often need to be socketed into weak and weathered rock strata, such as marl stratum. When these strata are ice-rich, the meltwater caused by construction will form an ice film at the pile-rock interface during refreezing, leading to a reduction in pile bearing capacity. By analyzing the shear mechanism of pile-rock interface with ice film, an interface shear model was proposed in this paper. Based on this model, the load transfer analytical method of rock-socketed bored piles was improved. Finally, the effects of pile-rock interface roughness, ice filling degree, and residual friction angle on skin friction were analyzed. The results show that the shear stress-displacement curve of the ice-containing interface unit exhibits two peaks and can be divided into four stages: ice film shear stage, ice film extrusion stage, concrete-rock relative sliding stage, and interface residual sliding stage. Increasing either the dilation angle or half-wavelength can improve the interface's shear resistance when only one variable is altered. Furthermore, the peak shear strength of the interface decreases as the filling degree increases. The interface residual shear stress is positively correlated with both the residual friction angle of weak rock (ϕ u − r) and ice (ϕ i − r), and increasing the proportion of ice in the residual sliding surface will lead to the reduction of residual shear stress. • In the presence of ice interlayer at pile-rock interface, the shear process can be divided into four stages. • The calculation model of skin friction for rock-socketed piles in ice-rich permafrost regions was improved. • The effects of interface roughness, ice filling degree, and residual friction angle on skin friction were analyzed. [ABSTRACT FROM AUTHOR]

In this paper, a method was developed to assess the vertical response of piles considering crushing characteristics. A load transfer model of a pile is built and the relationship between the crushing characteristics and load transfer function of a pile was analyzed. Based on the analysis results, the transfer equation of load function considering the crushing characteristics was derived using the finite difference method. The ideal side resistance and the load transfer mechanism of a pile can be obtained by the transfer equation of load function. The predicted response of piles with the proposed method is in good agreement with the response observed in some pile tests reported in the literature. Further study was conducted to discuss the effect of the parameters related to the load transfer model considering crushing characteristics on the load-settlement response of a single pile. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A significant decrease in sediment yield during the past six decades was detected. • The contribution of anthropogenic activities to sediment yield was quantified. • The multi-temporal scale flow–sediment relationship was evaluated. • Dam construction played an important role in sediment yield reduction. Abstract The water and sediment yields of rivers are changing substantially under the impacts of climate variability and anthropogenic activities, which are increasingly becoming an important research topic in the field of hydro-environmental science. This study presents a comprehensive investigation of the changes in runoff depth (h), specific sediment yield (SSY), and flow-sediment relationship at multi-temporal scales in the Han River Basin (HRB). The effects of climate variability and anthropogenic activities on SSY were quantified by employing double cumulative curve analysis. The results are as follows: (1) The annual and flood season h and SSY in the midstream (Huangzhuang Station) during the past six decades presented declining trends. The detected change points (i.e., 1968 and 1984) in SSY were linked to the reservoir and dam construction and soil and water conservation programs. The Danjiangkou (DJK) Reservoir impounded water in the flood season and supplied water in the non-flood season, which made the intra-annual distributions of h and SSY more even and the intra-annual variations more moderate in the comparisons between the pre- and post-change periods. (2) The annual and flood-season flow-sediment relationships were fitted with the power function and the sediment productive ability of runoff in the flood season was much greater than that in the non-flood season. The construction and operation of the DJK Reservoir intercepted a significant quantity of sediment; thus, the sediment transported by unit runoff largely declined. (3) The estimated relative contributions of climate variability and anthropogenic activities to the changes in SSY suggested that the anthropogenic activities played a more substantial role in the SSY decline after the transition years. Sustainable development of the HRB will face many challenges as the water and sediment discharges decrease further from the Han River into the Yangtze River. These results will provide a reference for better soil and water resource conservation and draw more attention to strengthen the river basin management. [ABSTRACT FROM AUTHOR]

An analytical solution for the karst water inflow into a lined tunnel in an infinite plane is derived based on conformal mapping. The new solution considers the center distance between the tunnel and the cavern, the radii of the tunnel and the cavern, and the property of the lining, such as the permeability coefficient as well as the lining radius. Numerical models are established and calculated using the finite difference software FLAC3D to compare with the analytical solution of inversion transformation, and a good agreement is found. Then, the parameters of effect are discussed in detail. The results indicate that the karst water inflow shows a curve relationship as the radius of tunnel increase and increases as the lining becomes thinner or the permeability coefficient of the lining increases. Moreover, the pressure head decreases as the tunnel radius and the center distance between the tunnel and the cavern increase. [ABSTRACT FROM AUTHOR]

Highlights • We quantified the soil erosion change in a spatially explicit manner. • We investigated the driving forces of soil erosion change. • The hydrological effects of soil and water conservation were assessed. • The limitations and sustainability of soil and water conservation were discussed. Abstract Land degradation is a global environmental problem that threatens human safety and socioeconomic development. In order to alleviate severe soil erosion, China has implemented historically unprecedented large-scale afforestation. In this study, we selected the most severely eroded Loess Plateau as a case, to assess the effectiveness of soil and water conservation (SWC) efforts based on the Revised Universal Soil Loss Equation. In addition, the underlying drivers for soil erosion changes and hydrological effects of SWC were investigated, and finally the potential policy implications of our findings were discussed. The soil erosion intensity from 2000 to 2015 was weakened largely due to favorable climate conditions and SWC efforts, which promoted vegetation restoration and enhanced soil retention. However, there was a significant trade-off between water provision and soil retention functions. The excessively artificial afforestation reduced sediment yield but depleted surface runoff. Furthermore, artificial afforestation and increasing irrigation water consumption overused groundwater resources and finally lowered groundwater table. The SWC efforts characterized by artificial afforestation induced soil moisture declining, particularly for the conversion type of farmland to forest/shrub. Our results suggested that afforestation might be a poor choice in arid and semiarid regions, because it did not consider local precipitation conditions, and have exacerbated water shortages and offset SWC efforts. Therefore, the future ecological restoration efforts should be transformed from simple species-based measures to optimal plant species combinations to minimize the tradeoff between water yield and soil retention. The strategies for ecological restoration of drylands should also account for water balance to ensure effectiveness and sustainability. [ABSTRACT FROM AUTHOR]

Highlights • Wind erosion status was assessed in the most seriously eroded area of China. • The constraint effects among climate, vegetation, and soil erosion were revealed. • The underlying drivers for wind erosion were investigated. • The implications of constraint effects on land degradation control were discussed. Abstract Soil erosion is a widespread environmental problem, which threatens the environmental sustainability. The northwest arid region (NAR) in China is known as one of the most severe soil loss in the world that suffering from wind erosion. Based on the Revised Wind Erosion Equation (RWEQ), the spatio-temporal change of wind erosion was identified, and the underlying drivers and influencing factors of soil erosion process were investigated. In addition, the implications of constraint effects in soil erosion control were discussed. The results showed that the wind erosion from 1990 to 2013 was substantially lessened, and the government-aided desertification prevention and control programs, as well as increasing precipitation and decreasing wind speed might have contributed to these trends. The constraint line analyses indicated that the vegetation cover had nonlinear and threshold effects on soil erosion through constraining the water condition (precipitation). Specifically, when the precipitation is below the threshold (approximately 50–100 mm yr−1 in the NAR), the precipitation (water condition) is not sufficient to maintain a good vegetation cover (about 20–40%), therefore the vegetation cannot efficiently prevent wind erosion. However, once the precipitation exceeds this threshold, the vegetation's sand retention function will enhance and thereby reducing soil loss substantially. Vegetation cover has a lower and an upper threshold for controlling wind erosion. A plant cover lower than 10% does little to reduce wind velocity at the soil surface. The effect of vegetation on reducing wind erosion basically reaches the maximum when plant cover is 40% or above. The constraint effects of precipitation on vegetation cover in the arid region should be considered to improve the efficiency of afforestation and reforestation efforts aiming at mitigating and preventing soil loss. [ABSTRACT FROM AUTHOR]

This paper considers a single-machine scheduling problem with deteriorating jobs and convex resource allocation. We assume that the actual processing time of a job is a function of its convex resource allocation and its starting time. For the multi-objective single-machine scheduling problem, we show that the problem is polynomially solvable in O (n log n) time, where n is the total number of jobs. [ABSTRACT FROM AUTHOR]

Abstract Soil erosion is a widespread environmental problem that threatens environmental sustainability. The Loess Plateau (LP) in China is one of the most severely eroded areas in the world. In this study, the soil erosion dynamics were assessed by applying the Revised Universal Soil Loss Equation and the Revised Wind Erosion Equation; further, the underlying drivers for soil erosion processes were investigated. In addition, implications of constraint effects in soil erosion control were discussed. The results showed that there was a substantial reduction in both wind and water erosion between 2000 and 2015; it is considered that vegetation restoration (mainly in relation to government-aided ecological restoration programs), increased precipitation, and a decrease in wind speed may have contributed to these trends. Land cover and soil properties contribute to spatial patterns of soil erosion. Thus, ecological restoration programs have promoted improvements in soil properties, leading to an eventual reduction. Constraint line analysis indicates that vegetation cover has a nonlinear and threshold effect on soil erosion through constraining the water condition (i.e., rainfall). With respect to water erosion, when rainfall is below the threshold (approximately 450–500 mm), it is not sufficient to maintain a good vegetation cover (about 30–40%), and vegetation cannot efficiently prevent soil erosion; however, once rainfall exceeds the threshold, the soil retention function of the vegetation is enhanced and soil loss is substantially reduced. In addition, there is a lower (10%) and an upper (40%) threshold at which vegetation can control wind erosion, which implies that plant cover lower than 10% has a minimal effect on reducing the wind velocity at the soil surface, and the effect of vegetation on reducing wind erosion is at its maximum when plant cover is 40% or above. However, if human intervention is removed, the limited amount of rainfall on the LP would be insufficient to support large areas of trees in the long-term; therefore, the constraint effects of the water condition on vegetation cover need to be considered to improve the efficiency of afforestation and reforestation efforts aimed at mitigating and preventing soil loss. Highlights • We quantified the soil erosion change in a spatially explicit manner. • We investigated the driving forces of soil erosion change. • The constraint effect between wind erosion and vegetation cover was quantified. • The implications of constraint effect in soil erosion control were discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Anisotropic fracture toughness of AISI 420 built by selective laser melting is found. • Effects of tempering treatment and microstructure on the anisotropy are studied. • Fracture toughness is greater for loading direction parallel to the build direction. • Elongated cells are mainly responsible for the anisotropic behavior. • Fracture toughness is enhanced by a tempering treatment at 400 °C. Anisotropic fracture toughness of selective laser melted AISI 420 built in two build directions was investigated. Post-process heat treatments were performed at 200 °C and 400 °C to study the tempering effect. The parallel group exhibited better fracture toughness than the perpendicular group in both as-built and tempered states. K IC value of the 400 °C tempered state was superior to that of other states due to a coarser martensite phase. Elongated cellular structure was responsible for the anisotropic behavior because of a build direction effect, while the anisotropy was barely changed by the tempering treatments. [ABSTRACT FROM AUTHOR]

Large-scale plantations of Moringa oleifera Lam. are carrying out in the dry-hot valley of Red River in Yunnan Province to make it the core cultivation area in China. Nevertheless, there is a deficient understanding of detailed pollen flow patterns, which leads to uncertainty in designing and managing seed orchards of M. oleifera to fit the breeding demand. In order to facilitate the design of breeding strategies for inbreeding lines, paternity analysis by SSR (Simple Sequence Repeat) was used to estimate the outcrossing rate and pollen mediated gene flow of M. oleifera . The analysis was carried out in an experimental population domesticated in the dry-hot valley area of Red River with two germplasms (India and Myanmar) of 60 trees, including 12 maternal trees and 60 pollen donors (bisexual flowers, maternal trees were also possible paternal trees in case of selfing). One hundred fifteen seeds out of 288 were confirmed pollen donors by 8 microsatellite loci at 95% strict confidence level. The multilocus outcrossing rate is t m  = 0.797 ± 0.096, and single-locus outcrossing rate is t s  = 0.742 ± 0.058. Pollen dispersal distance varied from 0 m (self-pollination) to 24.7 m, with an average of 11.9 m, and 95% of effective pollen was dispersed within 20 m, indicating that the effective pollen mediated gene flow is restricted to a limited distance. 50.3% of effective pollen was donated by 9 trees. Moreover, there was no apparent correlation between pollen dispersal distance and pollen contribution rate, as well as between germplasm and reproducibility. The maximum pollen dispersal distance between two trees estimated in this experimental stand is highly localized at current 3 × 3 m planting density, indicating that M. oleifera seed orchards and clones could be planted nearer to each other than previously thought (as far as kilometers). [ABSTRACT FROM AUTHOR]

Human demands for natural resources have significantly changed the natural landscape and induced ecological degradation and associated ecosystem services. An understanding of the patterns, interactions, and drivers of ecosystem services is essential for the ecosystem management and guiding targeted land use policy-making. The Losses Plateau (LP) provides ecosystem services including the carbon sequestration and soil retention, and exerts tremendous impacts on the midstream and downstream of the Yellow River. Three dominant ecosystem services between 2000 and 2012 within the LP were presented based on multiple source datasets and biophysical models. In addition, paired ecosystem services interactions were quantified using the correlation analysis and constraint line approach. The main conclusions are as follows. It was observed that the warming and wetting climate and ecological program jointly promoted the vegetation growth and carbon sequestration. The increasing precipitation throughout 2000–2012 was related to the soil retention and hydrological regulation fluctuations. The vegetation restoration played a positive role in the soil retention enhancement, thus substantially reduced water and sediment yields. The relationships between ecosystem services were not only correlations (tradeoffs or synergies), but rather constraint effects. The constraint effects between the three paired ecosystem services could be classified as the negative convex (carbon sequestration vs. hydrological regulation) and hump-shaped (soil retention vs. carbon sequestration and soil retention vs. hydrological regulation), and the coefficients of determination for the entire LP were 0.78, 0.84, and 0.65, respectively. In the LP, the rainfall (water availability) was the key constraint factor that affected the relationships between the paired ecosystem services. The spatially explicit mapping of ecosystem services and interaction analyses utilizing constraint line approach enriched the understanding of connections between ecosystem services and the potential drivers, which had important implications for the land use planning and landscapes services optimizing. [ABSTRACT FROM AUTHOR]