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In this article, a kind of original bamboo-fiber reinforced phosphogypsum composite wall was proposed. The axial compression tests of eight walls and finite element analysis were carried out. The failure modes and mechanical properties of the walls were explored, the influence of parameters on the axial compression performance of the walls was studied, and the calculation methods of the axial compression capacity and stiffness of the composite walls were proposed. The results show that the phosphogypsum cracked first in the composite walls during the loading process, the cracks gradually spreaded through and widened, and the bamboo tubes inside the composite walls were crushed. The buckling failure occurred in the pure original bamboo wall. The bearing capacity of the composite wall control specimen is 140% and 38.46% higher than that of the pure phosphogypsum wall and the pure original bamboo wall, respectively. The number of dovetail nails has no significant effect on the axial compression performance of the composite wall. The bearing capacity and stiffness of composite wall increase with the increase of bamboo number, wall thickness, bamboo wall thickness and phosphogypsum strength. The calculation method of axial bearing capacity and stiffness of composite wall based on bamboo content is proposed. The finite element simulation results are in good agreement with the experimental and theoretical calculation results. The theoretical calculation method has high accuracy. The composite wall realizes the complementary advantages of original bamboo and phosphogypsum, which provides reference for the development and application of green buildings. [ABSTRACT FROM AUTHOR]

For point clusters, the conflict and crowding of map symbols is an inevitable problem during the transition from large to small scales. The cartographic generalization involved in this problem as a spatial decision-making process is usually related to the analysis of spatial context, the choice of abstraction operators, and the judgment of the resulting data quality. The rules summarized by traditional generalization methods usually require manual setting of conditions or thresholds and sometimes encounter special cases that make it difficult to directly match certain rules or integrate different rules together. An alternative method is using a data-driven strategy under AI technology background to simulate cartographer behaviors through typical sample training, such as deep learning. The integration of cartography domain knowledge and deep learning is a better choice to settle generalization decisions. This study uses a combination of domain knowledge and a data-driven approach to introduce graph neural networks into point cluster generalization. First, we construct a virtual graph structure of point clusters using Delaunay triangulation, secondly, we extract spatial features, contextual features, and attributes of each point separately, and then propose a generalization model based on the TAGCN network. Finally, this model is trained with the manually generalized sample to realize the automatic point cluster generalization. The results demonstrate that the proposed model is valid and efficient for point cluster generalization and that this algorithm can better maintain various characteristics of the point cluster in both the local area and the overall map compared to other methods. [ABSTRACT FROM AUTHOR]

The longitudinal compressive properties and stress–strain relationship of original bamboo at different culm heights were studied by a uniaxial compression experiment. The experimental results show that the failure mode of bamboo is bulging failure, and its ultimate compressive strength increases linearly with the increase of height at the bamboo culm. The longitudinal compressive stress–strain curves of bamboo at different heights are normalized, and the three-stage nonlinear constitutive model and the Boltzmann constitutive model are established. The two models are close to the experimental results and can describe the main stages of bamboo compression. A finite element model of the compression specimen is established to verify the accuracy of the proposed constitutive model, and bamboo column models with different slenderness ratios are established to evaluate the feasibility of the proposed constitutive model in buckling analysis. The results show that the finite element model can well simulate the buckling capacity of the bamboo column after introducing the initial defect of L/500, while the slenderness ratio is greater than 30. This work is expected to be useful for the finite element analysis of bamboo and prediction of buckling capacity of original bamboo columns. [ABSTRACT FROM AUTHOR]

To reasonably determine the design strengths of bamboo, in this work, the tensile strength parallel to particles, compressive strength parallel to particles, tensile strength perpendicular to particles, and compressive strength perpendicular to particles of bamboo were systematically investigated. The tensile strength parallel to the grain of the bamboo material was the highest, and it reached the minimum when perpendicular to the grain. The influence of the functional form of the probability distribution and data points for fitting on the reliability was evaluated by the first and second-moment checking point method. It was recommended to use the fitting results of the first 15% strength data and the 2-P-Weibull probability distribution model to determine the design values of the bamboo strength. On the basis of reliability analysis, the variation rule of reliability index and resistance coefficient of bamboo under different load combination types and load-effect ratios was calculated. The optimum partial resistance coefficient of the bamboo was determined by minimising the sum of squares of error, and the design strength of the bamboo was determined accordingly. [ABSTRACT FROM AUTHOR]

This paper proposes a model to quantify the multiscale representation of a polyline based on iterative head/tail breaks. A polyline is first transformed into a corresponding Fourier descriptor consisting of normalized Fourier-series-expansion coefficients. Then, the most significant finite components of the Fourier descriptor are selected and ranked to constitute the polyline constrained Fourier descriptor. Using Shannon's information theory, information content of the constrained Fourier-descriptor components is defined. Next, head/tail breaks are introduced to iteratively divide the constrained Fourier descriptor into head and tail components according to the heavy-tailed distribution of information contents. Thus, simplified polylines are reconstructed using ordered heads generated from head/tail breaks. Finally, the radical law is introduced and applied to model multiscale polyline representation by quantifying the scale of each simplified polyline. Three experiments are designed and conducted to evaluate the proposed model. The results demonstrate that the proposed model is valid and efficient for quantifying multiscale polyline representation. [ABSTRACT FROM AUTHOR]

Keratin-based drug carriers have attracted great interest due to their intrinsic biocompatibility and tumor micro-environmental responsiveness. In the study, keratin was first extracted from human hair with reduction method. The reduced keratin was successively conjugated with poly(ethylene glycol) (PEG) via thiol Michael addition reaction and iodoacetic acid (IAA) via substitution reaction to impart both physical stability and acidity responsiveness. Subsequently, the conjugated keratin was fabricated into micelles and loaded with doxorubicin (DOX) by self-assembly. The micelles exhibited pH, glutathione (GSH) and enzyme (trypsin) triple-responsiveness as well as charge reversibility under the simulated tumor microenvironment. These drug-loaded micelles exhibited high toxicity against A549 cells with low side effect on normal cells. Furthermore, anticancer efficacy in vivo revealed DOX-loaded micelles presented higher therapeutic efficiency than free DOX. Moreover, these micelles were stable under physiological conditions, and could be internalized through endocytosis without hemolysis. Based on the results, the drug-loaded micelles were satisfactory candidates for drug carriers. [ABSTRACT FROM AUTHOR]

In this essay, the effect of the morphology of the CeO2 support and the Ba promoter on the ammonia synthesis reaction was studied. CeO2 support with {110} and {100} crystal planes and more oxygen vacancies enhanced the catalytic activity of ammonia synthesis. The relatively uniform microspheres structure CeO2 support (CeO2-MS) with {110} and {100} crystal planes was synthesized. The structural functions of the as-synthesized CeO2 support for the Ru-based catalyst were investigated in the ammonia synthesis reaction. The results of catalytic performance showed that the catalytic activity of 2.5%Ru/CeO2-MS catalyst reached 8940 μmol· g−1· h−1 at 450 ℃, 3.8 MPa, H2/N2 = 3 (60 mL∙min−1), which is higher nearly 2.5 times than the 2.5%Ru/CeO2-commercial (CeO2-C). And the catalytic activity of catalysts increased with the increase of reaction temperature. The activity of 6%Ba-2.5%Ru/CeO2-MS (24000 μmol· g−1· h−1) catalyst increased about 268% than that of catalyst without addition of Ba. Their physical and chemical properties were characterized by XRD, BET, HRTEM, H2-TPR, H2-TPD, and XPS analyses. Our results indicate that the 2.5%Ru/CeO2-MS catalyst and catalysts involving promoters (Cs, K, and Ba) exhibit significant support-morphology-dependent catalytic activity for ammonia synthesis. [ABSTRACT FROM AUTHOR]

Keratin is a promising material for building drug carriers due to their biocompatibility, reduction sensitivity, and biodegradability. Herein, we aim to develop acid and glutathione (GSH) dual-responsive keratin-based drug carriers with a one-step strategy. Keratin/DOX complexes were first prepared by means of a simple mixing approach, followed by desolvation and crosslinking to prepare keratin-based drug loaded nanoparticles (KDNPs). The as-prepared KDNPs showed negative-charged surface and globular morphology with the diameter of ca. 129 nm. The drug-loading rate was as high as 14% as a result of electrostatic attraction. Drug delivery profile showed that KDNPs performed pH and GSH dual responsiveness as well as charge reversibility in the simulated tumor microenvironment. MTT assay demonstrated that KDNPs exhibited enhanced inhibitory efficiency against A549 cells. Moreover, CLSM observation suggested that these KDNPs were internalized through endocytosis pathway. All of these results demonstrated that keratin based drug carriers had potential of tumor therapy. [ABSTRACT FROM AUTHOR]

Foam flooding is one of the effective techniques during thermal recovery process in heavy oil reservoir. Nitrogen is generally co-injection with the foaming agent for the generation of foam. However, the mechanism has not been totally understood, thereby requiring further discussion. In this study, a series of sand pack experiments for nitrogen foam steam flooding were designed and conducted. A comparison of influencing factors, including gas-liquid (foaming agent) ratio, permeability, injection scheme, and oil saturation was used to evaluate the stability and blocking mechanisms of foam. The results show that the blocking capacity of the gas-liquid ratio of 1:1 is the greatest in all cases under high-temperature condition. The blocking mechanism of foam is analyzed, which indicates that foam is selective to block larger pores and throats in porous media with high-permeability. And also, the stability of foam becomes worse while meeting oil. This characteristic is favorable for improving the sweep efficiency to enhance oil recovery in developing heavy oil reservoir. [ABSTRACT FROM AUTHOR]

The representation and analysis of building patterns are critical for characterizing urban scenes and making decisions in urban planning. The evaluation of building patterns is a difficult spatial analysis problem that exhibits properties of symbolization, homogeneity and regularity. Open issues in this field include the development of approaches for representing building patterns and vector-based methods for computing various pattern metrics. In the image analysis domain, there are many methods for pattern recognition (e.g., texture analysis), but there are few corresponding solutions for vector data. The aim of this research is to develop several building pattern metrics and offer a texton co-occurrence matrix (TCM)-based method to quantitatively evaluate the features of building patterns. The procedure first constructs a spatial field based on a Delaunay triangulation skeleton to partition a set of buildings into a set of tessellation cells. The tessellations of building clusters have a similar structure as image representations, in that each cell corresponds to an image pixel. We then use the texton analysis to establish a matrix to describe the tessellation structure, including the neighboring relationships and individual attribute information. Finally, a set of feature descriptors is obtained from the TCM to capture the texture-related information of building groups. Through experiments on building pattern analysis and spatial queries, we show that the results of TCM-based evaluation of building patterns are consistent with those of human cognition. [ABSTRACT FROM PUBLISHER]

Automatic generation of multi-scale representations from the same spatial data source has been the research focus in map generalization for a long time. Based on the Fourier technique, this paper proposes a continuous, multi-scale representation model for progressive transformation of cartographic curves on the Internet. In our method, all the curves, whether closed or open, are depicted as periodical functions which are further expressed as Fourier series. The convergence degrees of the Fourier series are explored for different kinds of curves, and truncating frequencies are derived based on the similarity between the original and reconstructed curves. Using information theory and the Radical Law in cartography, the relationship between map scales and Fourier frequencies is established. Based on the proposed multi-scale model, we also introduce the principles and implementation of a progressive transmission method. Our method is evaluated using the contours from a topographic map. The results show that our model is a valid approach to multi-scale representation of cartographic curves. [ABSTRACT FROM AUTHOR]

Bone morphogenetic protein-2 (BMP-2) is a multi-functional growth factor belonging to the transforming growth factor β superfamily that has a broad range of activities that affect many different cell types. BMP-2 induces odontoblastic differentiation of human dental pulp cells (DPCs), but the underlying mechanism remains unclear. In this study, we investigated the potential role of the JNK mitogen-activated protein kinases (MAPK) pathway in BMP-2-induced odontoblastic differentiation of DPCs. The levels of phosphorylated and unphosphorylated JNK MAPK were quantified by Western blot analysis following treatment with BMP-2 and the JNK inhibitor SP600125. The role of JNK MAPK in the BMP-2-induced odontoblastic differentiation of DPCs was determined by measuring alkaline phosphatase (ALP) activity and by examining the expression of odontoblastic markers using quantitative real-time polymerase chain reaction analysis. The effect of JNK MAPK silencing on odontoblastic differentiation was also investigated. BMP-2 upregulated the phosphorylation of JNK in DPCs in a dose- and time-dependent manner. Early markers of odontoblastic differentiation, including ALP activity, osteopontin and dentin matrix protein-1, were not inhibited by the JNK inhibitor. However, the JNK inhibitor, SP600125, significantly inhibited late-stage differentiation of odontoblasts, including the gene expression of osteocalcin, dentin sialophosphoprotein and bone sialoprotein, and also reduced the formation of mineralized nodules in BMP-2-treated DPCs. Consistent with this observation, silencing of JNK MAPK also decreased late-stage odontoblastic differentiation. Taken together, these findings suggest that JNK activity is required for late-stage odontoblastic differentiation induced by BMP-2. [ABSTRACT FROM AUTHOR]

Reconstructing highly comminuted articular fractures poses a difficult surgical challenge, akin to solving a complicated three-dimensional (3D) puzzle. Preoperative planning using computed tomography (CT) is critically important, given the desirability of less invasive surgical approaches. The goal of this work is to advance 3D puzzle-solving methods towards use as a preoperative tool for reconstructing these complex fractures. A methodology for generating typical fragmentation/dispersal patterns was developed. Five identical replicas of human distal tibia anatomy were machined from blocks of high-density polyetherurethane foam (bone fragmentation surrogate), and were fractured using an instrumented drop tower. Pre- and post-fracture geometries were obtained using laser scans and CT. A semi-automatic virtual reconstruction computer program aligned fragment native (non-fracture) surfaces to a pre-fracture template. The tibiae were precisely reconstructed with alignment accuracies ranging from 0.03 to 0.4 mm. This novel technology has the potential to significantly enhance surgical techniques for reconstructing comminuted intra-articular fractures, as illustrated for a representative clinical case. [ABSTRACT FROM AUTHOR]