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Tobacco (Nicotiana tabacum L.) is an economically important and relatively drought-tolerant crop grown around the world. However, the molecular regulatory mechanisms involved in tobacco root development in response to drought stress are not wellknown. To gain insight into the transcriptome dynamics associated with drought resistance, genome-wide gene expression profiling of roots from a tobacco cultivar (Honghua Dajinyuan, a major flue-cured tobacco cultivar in Southwest China) under 20% PEG6000 treatment for 0, 6 h and 48 h were conducted using Solexa sequencing (Illumina Inc., San Diego, CA, USA). Over five million tags were generated from tobacco roots, including 229,344, 221,248 and 242,065 clean tags in three libraries, respectively. The most differentially expressed tags, with either log2FC > 2.0 for up-regulated genes or log2FC < -2.0 for down regulated genes (p < 0.001), were analyzed further. In comparison to the control, 1476 up-regulated and 1574 down-regulated differentially expressed genes (DEGs) were identified, except for unknown transcripts, which were grouped into 43 functional categories involved in seven significant pathways. The most enriched categories were those that were populated by transcripts involved in metabolism, signal transduction and cellular transport. Many genes and/or biological pathways were found to be common among the three libraries, for example, genes participating in transport, stress response, auxin transport and signaling, etc. Next, the expression patterns of 12 genes were assessed with quantitative real-time PCR, the results of which agreed with the Solexa analysis. In conclusion, we revealed complex changes in the transcriptome during tobacco root development related to drought resistance, and provided a comprehensive set of data that is essential to understanding the molecular regulatory mechanisms involved. These data may prove valuable in future studies of the molecular mechanisms regulating root development in response to drought stress in tobacco and other plants.

Additive manufacturing of AlSi10Mg has obtained increased attention due to its lightweight feature. However, handling of loose powder, efficient usage of feedstock, and powder recycling still remain major open challenges. Herein, a novel additive manufacturing method based on metal additive manufacturing using powder sheet (MAPS) is proposed, which leverages composite flexible films made of the feedstock of metal powder and a polymeric binder, aiming to extend the range of applicability of AlSi10Mg-based additive manufacturing technologies, for example, vehicle components. In situ high-speed imaging is used to explore the underlying manufacturing mechanisms of the proposed MAPS concept and investigate the laser–powder sheet interaction. In addition, a representative computational thermo-mechanical model was used to evaluate the substrate deformation due to the printing process, a critical aspect that must be minimized in order to transfer this technology to larger scale applications. [ABSTRACT FROM AUTHOR]

The article titled "Material incorporation in powder sheet additive manufacturing toward lightweight designs for future mobility" was published in the Journal of Laser Applications. The article originally contained errors in Table I, specifically in the placement of data from the second row, third and fourth columns. The errors were corrected in all online versions of the article on May 23, 2024. The article provides thermophysical properties required by a numerical model for various materials used in additive manufacturing. The authors of the article are Wenyou Zhang, Daniele Pullini, Matteo Alberghini, Andrea Bertinetti, Alessio Tommasi, Asli Coban, Seán McConnell, Himani Naesstroem, Ramesh Padamati Babu, Joerg Volpp, and Rocco Lupoi. [Extracted from the article]

Over-application of chemical fertilizers and continuous cropping obstacles seriously restrict the sustainable development of tobacco production. Localized fertilization of beneficial microbes has potential advantages in achieving higher productivity, but the underlying biological mechanisms of interactions between rhizospheric microorganisms and the related metabolic cycle remain poorly characterized. Here, an integrative analysis of microbiomes with non-targeted metabolomics was performed on 30 soil samples of rhizosphere, root surrounding, and bulk soils from flue-cured tobacco under continuous and non-continuous monocropping systems. The analysis was conducted using UPLC-MS/MS platforms and high-throughput amplicon sequencing targeting the bacterial 16S rRNA gene and fungal ITS gene. The microbial inoculant consisted of Bacillus subtilis , B. velezensis, and B. licheniformis at the ratio of 1:1:1 in effective microbial counts, improved the cured leaf yield and disease resistance of tobacco, and enhanced nicotine and nitrogen contents of tobacco leaves. The bacterial taxa Rhizobium , Pseudomonas , Sphingomonadaceae , and Burkholderiaceae of the phylum Proteobacteria accumulated in high relative abundance and were identified as biomarkers following the application of the microbial inoculant. Under continuous monocropping, metabolomics demonstrated that the application of the microbial inoculant significantly affected the soil metabolite spectrum, and the differential metabolites were significantly enriched to the synthesis and degradation of nicotine (nicotinate and nicotinamide metabolism and biosynthesis of alkaloids derived from nicotinic acid). In addition, microbes were closely related to the accumulation of metabolites through correlation analysis. The interactions between plant roots and rhizospheric microorganisms provide valuable information for understanding how these beneficial microbes affect complex biological processes and the adaption capacity of plants to environments.IMPORTANCEThis study elaborated on how the microbial fertilizer significantly changed overall community structures and metabolite spectrum of rhizospheric microbes, which provide insights into the process of rhizosphere microbial remolding in response to continuous monocropping. we verified the hypothesis that the application of the microbial inoculant in continuous cropping would lead to the selection of distinct microbiota communities by establishing models to correlate biomarkers. Through correlation analysis of the microbiome and metabolome, we proved that rhizospheric microbes were closely related to the accumulation of metabolites, including the synthesis and degradation of nicotine. The interactions between plant roots and rhizospheric microorganisms provide valuable information for understanding how these beneficial microbes affect complex biological processes and the adaption capacity of plants to environments., Competing Interests: The authors declare no conflict of interest.

Laser beam powder bed fusion (PBF-LB) is a leading technique among metal additive manufacturing (AM), and it has a wide range of applications in aerospace and medical devices. Most of the existing PBF-LB process modeling is mainly based on the fabrication of a single part on a large build plate, which is not reflective of the practical multipart PBF-LB manufacturing. The effects of batch size on the thermal and mechanical behavior of additively manufactured parts have not been investigated. In this work, the multipart PBF-LB thermomechanical modeling framework was proposed for the first time. The effects of sample numbers (1, 2, and 4) on temperature and residual stress (RS) of part-scale components were computationally investigated. It is found that RS within the parts decreased with increasing number of components per build. Parts located at the central areas of the build plate had larger RS than at the border. These findings can be beneficial for informing AM designers and operators of the optimum printing setup to minimize RS of metal parts in PBF-LB., Competing Interests: No competing financial interests exist., (Copyright 2023, Mary Ann Liebert, Inc., publishers.)

Aims : Berberine (BBR) improves beta-cell function in Type 2 diabetes (T2D) because of its anti-apoptotic activity, and our laboratory developed a new preparation named Huang-Gui Solid Dispersion (HGSD) to improve the oral bioavailability of BBR. However, the mechanism by which BBR inhibits beta-cell apoptosis is unclear. We hypothesized that the Group VIA Ca 2+ -Independent Phospholipase A 2 (iPLA 2 β)/Cardiolipin(CL)/Opa1 signaling pathway could exert a protective role in T2D by regulating beta-cell apoptosis and that HGSD could inhibit β-cell apoptosis through iPLA 2 β/CL/Opa1 upregulation. Methods : We examined how iPLA 2 β and BBR regulated apoptosis and insulin secretion through CL/Opa1 in vivo and in vitro . In in vitro studies, we developed Palmitate(PA)-induced apoptotic cell death model in mouse insulinoma cells (MIN6). iPLA 2 β overexpression and silencing technology were used to examine how the iPLA 2 β/CL/Opa1 interaction may play an important role in BBR treatment. In in vivo studies, db/db mice were used as a diabetic animal model. The pancreatic islet function and morphology, beta-cell apoptosis and mitochondrial injury were examined to explore the effects of HGSD. The expression of iPLA 2 β/CL/Opa1 was measured to explore whether the signaling pathway was damaged in T2D and was involved in HGSD treatment. Results : The overexpression of iPLA 2 β and BBR treatment significantly attenuated Palmitate- induced mitochondrial injury and apoptotic death compared with Palmitate-treated MIN6 cell. In addition, iPLA 2 β silencing could simultaneously partly abolish the anti-apoptotic effect of BBR and decrease CL/Opa1 signaling in MIN6 cells. Moreover, HGSD treatment significantly decreased beta-cell apoptosis and resulted in the upregulation of iPLA 2 β/CL/Opa1 compared to those of the db/db mice. Conclusion : The results indicated that the regulation of iPLA 2 β/CL/Opa1 by HGSD may prevent beta-cell apoptosis and may improve islet beta-cell function in Type 2 diabetic mice and in palmitate-treated MIN6 cells., Competing Interests: Competing Interests: The authors have declared that no competing interest exists.

Objective: To solve the fixation problem between ligament grafts and host bones in ligament reconstruction surgery by using ligament-bone composite scaffolds to repair the ligaments, to explore the fabrication method for ligament-bone composite scaffolds based on three-dimensional (3-D) printing technique, and to investigate their mechanical and biological properties in animal experiments., Methods: The model of bone scaffolds was designed using CAD software, and the corresponding negative mould was created by boolean operation. 3-D printing techinique was employed to fabricate resin mold. Ceramic bone scaffolds were obtained by casting the ceramic slurry in the resin mould and sintering the dried ceramics-resin composites. Ligament scaffolds were obtained by weaving degummed silk fibers, and then assembled with bone scaffolds and bone anchors. The resultant ligament-bone composite scaffolds were implanted into 10 porcine left anterior cruciate ligament rupture models at the age of 4 months. Mechanical testing and histological examination were performed at 3 months postoperatively, and natural anterior cruciate ligaments of the right sides served as control., Results: Biomechanical testing showed that the natural anterior cruciate ligament of control group can withstand maximum tensile force of (1 384 +/- 181) N and dynamic creep of (0.74 +/- 0.21) mm, while the regenerated ligament-bone scaffolds of experimental group can withstand maximum tensile force of (370 +/- 103) N and dynamic creep of (1.48 +/- 0.49) mm, showing significant differences (t = 11.617, P = 0.000; t = 2.991, P = 0.020). In experimental group, histological examination showed that new bone formed in bone scaffolds. A hierarchical transition structure regenerated between ligament-bone scaffolds and the host bones, which was similar to the structural organizations of natural ligament-bone interface., Conclusion: Ligament-bone composite scaffolds based on 3-D printing technique facilitates the regeneration of biomimetic ligament-bone interface. It is expected to achieve physical fixation between ligament grafts and host bone.