Properties and Engineering Applications of a New Goaf Grouting Filling Material

In the treatment of goafs in traffic engineering, technical problems such as those related to large-volume grouting and the precise control of material properties are often encountered. To address these issues, we developed a new composite material comprising cement-fly ash-modified sodium silicate (C-FA-MS). The setting time, fluidity, unconfined compressive strength, and microstructure were varied for different proportions of cement-sodium silicate (C-S) slurry, cement-fly ash-sodium silicate (C-FA-S) slurry, and C-FA-MS slurry, and their performances were compared and analysed. The experimental results showed that the initial setting time of the slurry was the shortest when both the original sodium silicate volume ratio ( V S ) and modified sodium silicate volume ratio ( V MS ) were 0.2. The final setting time of the C-S and C-FA-S slurries tended to decrease but then increased with decrease in V S , while that of the C-FA-MS slurry increased with lower V MS . The fluidity of the C-FA-S and C-FA-MS slurries decreased with decrease in V S or V MS at different fly ash admixture ratios. The consolidation compressive strength of C-S increased with decreasing V S , while that of C-FA-S showed a considerable increase only when V S decreased from 0.4 to 0.2. Meanwhile, the compressive strength of the C-FA-MS concretions first increased and then decreased with decrease in V MS . Microstructural analysis revealed that there were more cracks in the C-S agglomerate, the fly ash in the C-FA-S agglomerate reduced the relative density of the skeletal structure, and the stronger cross-linking in the C-FA-MS agglomerate improved the strength of the agglomerate. Under the condition of unit grouting volume, the cost of the C-FA-MS slurry was approximately 44.7% and 31.3% lower than that of the C-S and C-FA-S slurries, respectively. The new C-FA-MS material was applied for the treatment of the goaf in the Wu Sizhuang coal mine. Core drilling detection and audiofrequency magnetotelluric survey revealed that the goaf was sufficiently filled.

Investigation on the corrosion resistance of laser cladding Fe-based alloy coating against molten zinc

In this paper, laser cladding technology was used to prepare a Fe-based coating on H13 steel substrate and its corrosion behavior in molten zinc was studied. The results show that laser-cladding Fe-based coating can effectively protect the substrate from the corrosion of molten zinc, which is mainly related to its microstructure. The typical microstructure of the coating is composed of α-(Fe, Cr) solid solution matrix and CrFeB eutectic phases continuously distribute around the matrix. When molten zinc contacts with the surface of the coating, it corrodes the α phase matrix preferentially and CrFeB eutectic phases with better corrosion resistance interweave with each other to form a three-dimensional skeletal structure, which can play the role of diffusion barrier and slow down the diffusion rate of liquid zinc. The corrosion by molten zinc leads to the formation of a transition layer and an outer corrosion layer above the coatings. With the prolongation of the corrosion time, a large number of micro cracks are generated inside the transition layer and fracture gradually occurs under the action of thermal stress. The partial spalling of the transition layer and the corrosion of α phase matrix occur at the same time, making the corrosion depth of the coating increase continuously. However, the dense corrosion layer above the coating and the dispersed boride fragments can still function as a barrier to the inward diffusion of molten zinc.

Effect of Salvianolate on Myocardial Ischemia Reperfusion Injury and Its Mechanism

<sec> <title>Background:</title> The paper investigated the H9c2 cardiomyocyte model induced by hypoxia. Cell viability was monitored by real-time unlabeled cell function analyzer to determine the levels of LDH, MDA and SOD in cell supernatant. </sec> <sec> <title>Material and Methods:</title> The cytoskeleton staining was labeled by phalloidin staining. WB was applied to detect the expression of myocardial cytoskeleton microtubuleassociated protein and the expression of HIF-1α protein in each group. After adding AMPK inhibitor Compound C, Hoechst 33342 was employed to detect the apoptosis rate of cardiomyocytes, and WB was applied to detect the expressions of myocardial cytoskeleton-associated protein and p-AMPK. </sec> <sec> <title>Results:</title> Salvianolate can effectively improve cell viability, reduce LDH and MDA levels, increase SOD content, improve skeletal structure damage, reduce nuclear concentration, reduce cell debris, and promote the expressions of microtubule-associated protein, α-tubulin and β-tubulin, MAP4, and microfilament-associated protein MLCK, p-MLC-2 in myocardial cytoskeleton microtubules after ischemia and hypoxia. The addition of AMPK inhibitor can inhibit the expressions of p-AMPK, tubulin MAP4, microfilament protein MLCK and p-MLC-2 up-regulated by Salvianolate. </sec> <sec> <title>Conclusion:</title> Salvianolate can promote the expressions of microtubule-associated protein α-tubulin, β-tubulin,MAP4, microfilament-associated protein MLCK and p-MLC-2 in myocardial cytoskeleton after ischemia and hypoxia, indicating that Salvianolate can protect the myocardial cytoskeleton after ischemia and hypoxia, and may protect the structure and function of microtubules and microfilaments in the myocardial cytoskeleton through the AMPK/MAP4 and AMPK/MLCK pathways. </sec>

4D Structural root architecture modeling from digital twins by X-Ray Computed Tomography

Background Breakthrough imaging technologies may challenge the plant phenotyping bottleneck regarding marker-assisted breeding and genetic mapping. In this context, X-Ray CT (computed tomography) technology can accurately obtain the digital twin of root system architecture (RSA) but computational methods to quantify RSA traits and analyze their changes over time are limited. RSA traits extremely affect agricultural productivity. We develop a spatial–temporal root architectural modeling method based on 4D data from X-ray CT. This novel approach is optimized for high-throughput phenotyping considering the cost-effective time to process the data and the accuracy and robustness of the results. Significant root architectural traits, including root elongation rate, number, length, growth angle, height, diameter, branching map, and volume of axial and lateral roots are extracted from the model based on the digital twin. Our pipeline is divided into two major steps: (i) first, we compute the curve-skeleton based on a constrained Laplacian smoothing algorithm. This skeletal structure determines the registration of the roots over time; (ii) subsequently, the RSA is robustly modeled by a cylindrical fitting to spatially quantify several traits. The experiment was carried out at the Ag Alumni Seed Phenotyping Facility (AAPF) from Purdue University in West Lafayette (IN, USA). Results Roots from three samples of tomato plants at two different times and three samples of corn plants at three different times were scanned. Regarding the first step, the PCA analysis of the skeleton is able to accurately and robustly register temporal roots. From the second step, several traits were computed. Two of them were accurately validated using the root digital twin as a ground truth against the cylindrical model: number of branches (RRMSE better than 9%) and volume, reaching a coefficient of determination (R2) of 0.84 and a P < 0.001. Conclusions The experimental results support the viability of the developed methodology, being able to provide scalability to a comprehensive analysis in order to perform high throughput root phenotyping.

Ectopic Pregnancy Diagnosed Post Caesarean Surgery in a Three Year Old Boerboel Bitch

A three year old nulliparous Boerboel bitch presented with complaints of fever and inappetence six weeks after an elective caesarean section was diagnosed with an extrauterine foetus. A per-cutaneous abdominal ultrasound revealed a foetal sac showing a well-developed skeletal structure and the absence of foetal movement or heartbeat. During laparotomy, a foetal sac containing a dead foetus was located between the spleen and the stomach. The foetal sac was excised following ligation of its mesenteric attachment to the spleen. The previously operated uterus was observed to have involuted but revealed a small bud observed on the middle portion of the left uterine horn. The histological findings of the foetal sac revealed fibro-adipose tissue with numerous congested vessels. It was concluded that the Boerboel bitch had a secondary abdominal ectopic pregnancy and recommended that owing to the difficulty of diagnosing the condition before or during routine elective caesarean surgery, post-operative abdominal ultrasound would have been instructive.

The Application Status of Nanoscale Cellulose-Based Hydrogels in Tissue Engineering and Regenerative Biomedicine

As a renewable, biodegradable, and non-toxic material with moderate mechanical and thermal properties, nanocellulose-based hydrogels are receiving immense consideration for various biomedical applications. With the unique properties of excellent skeletal structure (hydrophilic functional groups) and micro-nano size (small size effect), nanocellulose can maintain the three-dimensional structure of the hydrogel to a large extent, providing mechanical strength while ensuring the moisture content. Owing to its unique features, nanocellulose-based hydrogels have made excellent progress in research and development on tissue engineering, drug carriers, wound dressings, development of synthetic organs, 3D printing, and biosensing. This review provides an overview of the synthesis of different types of nanocellulose, including cellulose nanocrystals, cellulose nanofibers, and bacterial nanocellulose, and describes their unique features. It further provides an updated knowledge of the development of nanocellulose-based functional biomaterials for various biomedical applications. Finally, it discusses the future perspective of nanocellulose-based research for its advanced biomedical applications.

The influence of edaphic factors on the vital state of large-flowered magnolia (Magnolia grandiflora L.). in the Nikitsky Botanical Gardens

The most widespread magnolia on the Southern coast of the Crimea and, in particular, in the Arboretum of the Nikitsky Botanical Gardens is the evergreen Magnolia grandiflora L., introduced in 1817. Currently, 28 generative specimens of Magnolia grandiflora of different ages grow in the Arboretum, including garden forms with different vital state. There are very few data on the relation of this species to soil conditions. For this reason, we have studied the influence of edaphic factors on the vital state of Magnolia grandiflora growing in the Arboretum of the Nikitsky Botanical Gardens. A number of limiting edaphic factors have been identified, the main of which is the high skeletal structure of the soil. The humus reserves in the soil have a positive effect on the vital state of trees. A high level of agricultural technology is the main method of improving the vital state of Magnolia grandiflora .

Human Recognition Using Joint Coordinate Images (JCIs) with Convolutional Neural Network

Human recognition with skeletal data has the advantage in detecting people without their face characteristic on image. However, the accuracy of recognition by this method is always low because it relies deeply on manual feature selection. We propose a novel human recognition method called Joint Coordinate Images (JCIs) with Convolutional Neural Network (CNN) based on the image generated from skeletal information tracked by KinectV1. In order to represent human physical skeletal characteristic, the coordinate values XYZ of human joint tracked by KinectV1 are firstly created in color image called Joint Coordinate Images (JCIs), in which the relative position of the pixels represents the skeletal structure characteristics of participants with shape in “大” structure. Secondly, a new convolution neural network classifier Lenet-5 model, which always performed well in image classification, was modified to be able to input our JCIs for human recognition. The experimental results show that human recognition using joint coordinate image and Lenet-5 network can reach the highest recognition accuracy of 90.00% on the G3D dataset, which demonstrates the feasibility to transform the skeletal coordinate information into color image for human recognition task and could be used as a complementary method to the well-known application of face recognition.

On the Structure and Properties of AlMgB14-TiB2 Composites Obtained from SHS Powders by Spark Plasma Sintering

AlMgB14-TiB2 composite materials were fabricated by self-propagating high-temperature synthesis (SHS) followed by spark plasma sintering of the obtained SHS products. It was found that, during the SHS, the AlMgB14 phase is formed at a donor (Ti + 2B) to acceptor (Al12Mg17-B) mass ratio of 3:7 and 4:6, respectively. The specimen sintered from the SHS powder with the donor:acceptor mass ratio of 5:5 at a temperature of 1470 °C has a uniform skeletal structure. The average hardness of the obtained specimen is 30.1 GPa.