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The poor shape of the cavity formed by the planar 5R parallel transplanting mechanism will cause Salvia miltiorrhiza seedlings to tilt while transplanting them. In order to improve the quality of the cavity in Salvia miltiorrhiza planting, this paper analyzed the structural composition and working principle of a planar 5R parallel transplanting mechanism for Salvia miltiorrhiza and established the bidirectional coupling model between the transplanting mechanism and the soil. Based on the model, a regression analysis model and the influence of three factors and five levels were obtained by using the experimental optimization design method, which reflected the relationship between the parameters of the mechanism on the parameters of the cavity. In terms of the optimization objective and regression model, the optimal parameter combination of the transplanting mechanism was obtained by multi-objective parameter optimization. A virtual test of cavity formation was conducted on the transplanting mechanism for Salvia miltiorrhiza with an optimal parameter combination. The results proved that the parameters of cavity output via the regression model and the measurement from the bidirectional coupling model were basically consistent, which verifies the accuracy of our parameter optimization for the transplanting mechanism. This paper provides a new approach to the sustainable improvement of a Salvia miltiorrhiza transplanting mechanism from the perspective of the interaction between the machine and the soil.

Iron-based specimens with boronized layers were prepared by boriding at 800 ℃, 900 ℃ and 1000 ℃ for 3, 5, and 7 hours, respectively. The thickness, microstructure, surface roughness, friction, and wear performance were studied. Results showed that the process parameters such as temperature, the time of boriding have remarkable impact on the thickness of the boronized layer. Dual-phase was generated at 1000 ℃ which lead to increased brittleness, lower surface hardness, and decreased adhesion to the substrate. Compared with specimens boronized at 1000 ℃ and 800 ℃, the surface structure of the boronized layer of specimens boronized at 900 ℃ is denser and uniform, the wear track is not damaged. The average friction coefficient and mass loss by wear of specimens boronized at 900 °C are smaller than that of boronized at 1000 ℃ and 800 ℃, indicating that specimens borided at 900 ℃ behave excellent friction and wear performance.

The UIO-66 membrane-derived ZrO2–In2O3 bimetallic core–shell catalyst exhibits an excellent catalytic performance in the reverse water gas shift reaction.

A geared five-bar transplanting mechanism can meet the agronomic requirements for the vertical planting of Salvia miltiorrhiza. In order to improve the planting quality, this paper analyzed the structural composition and working principle of a transplanting mechanism and established an interactive human–computer auxiliary interface through a kinematic model. With the aid of an auxiliary interface, by taking the parameters of the transplanting mechanism as the factors and the parameters of the absolute trajectory and posture for the planter as the index, an orthogonal experimental design with five factors and five levels was carried out, and the optimal combination of the parameters of the mechanism was obtained. According to the optimal combination of the parameters of the mechanism, the structure of the transplanting mechanism was designed, a geared five-bar transplanting mechanism for Salvia miltiorrhiza prototype was developed, and a test bench system was built. The actual trajectory of the endpoint for the transplanting mechanism’s prototype was obtained using high-speed photographic technology. The bench test results showed that according to a comparison of the actual trajectory, the posture for the planter and the theoretical analysis results were basically consistent, which verified the correctness, rationality, and consistency of the optimal design for the mechanism.

Mechanical-chemical synergy has been proven efficient in weed control. However, characterizing the state of the weed–soil complex after mechanical weeding and revealing its effects on subsequent herbicide application is still challenging, which restricts the implementation of this technology. This paper first presents a method to characterize the state of the weed–soil complex from the perspectives of the fragmentation and composite characteristics. The regrowth of the weed–soil complex and the effects of complemented herbicide-reduced spraying on weed control efficacy and crop yield were then investigated. The results showed that the typical diameters of the weed–soil complexes were 10.67 cm and 2.82 cm after inter-row hoe shovel and intra-row finger weeding, respectively. There were mainly two and four weed–soil complex states after inter-row and intra-row weeding, respectively. The regrowth rate corresponding to the weed–soil complex state with the largest component proportion after inter-row and intra-row weeding was 76.91% and 18.37%, respectively. The additional chemical herbicide sprayed on the weed–soil complex significantly improved the fresh weight control efficacy of 95.12% for the preposed inter-row mechanical weeding and 138.07% for the preposed intra-row mechanical weeding in the maize silking stage. The maize yield of inter-row mechanical–75% chemical application treatment was 9.27% higher than that of chemical treatment. Mechanical weeding creates a suitable weed–soil complex state for subsequent chemical application and improves the synergistic weeding effect.

Background In general, ZIF-8 tends to undergo ion responsive degradation in ionic solutions, which makes it difficult to maintain its original structure, thus restricting its direct application in biological settings. Methods ZIF-8 was synthesized using one-pot method and the ZIF-8/PCL scaffolds were built by a round mould or printed by melt electrowrittten (MEW) technology. Mineralization performance was evaluated by SEM with EDS-mapping and micro-CT scanning after soaking in simulated body fluid (SBF). The osteogenic activity in vivo or in vitro was assessed using different methods including micro-CT scanning, Alizarin red staining, and immunohistochemical staining. Results Herein, an abnormal phenomenon is reported that ZIF-8 can form large hydroxyapatite-like crystals when getting immersed directly in multi-ion simulated body fluid. The abnormal crystals showed the continuation of rapid growth in 14 days, with its volume increasing by more than ten times. As suggested by the release of Zn2+ and the emergence of new XRD diffraction peaks, ZIF-8 particles might gradually collapse and congregate through competitive coordination and re-nucleation. The above phenomenon is also observable on the surface of ZIF-8/PCL composite materials and MEW printing ZIF-8/PCL scaffolds. ZIF-8 increased the roughness of PCL by altering its surface topography, which significantly improved its biocompatibility and osteoinductivity both in vitro and in vivo. Notably, the capability of pro-biomineralization makes ZIF-8 also applicable in polylactic acid. Conclusions To sum up, the results shown in this study demonstrate that ZIF-8 can serve as a bioactive additive that enables the surface modification to synthetic polymers, which suggests its potential of application for in-situ bone regeneration.

Melatonin is an important phytohormone in plant development and stress responses. However, the functions of melatonin in rice salt tolerance during seed germination is largely undetermined. In this study, we investigated its potential molecular mechanism during rice seed germination under salinity through comprehensive transcriptome sequencing, metabolome profiling, and physiological assays. Transcriptome analysis revealed 4794 differentially expressed genes (DEGs) after melatonin pretreatment under salinity, including 2843 upregulated and 1951 downregulated genes. Functional annotation showed that many DEGs were associated with antioxidative activity and phytohormone biosynthesis and signal transduction. Consistent with the transcriptome results, physiological analysis revealed enhanced activity of antioxidant capacity, increased indole-3-acetic acid (IAA) level, and reduced abscisic acid (ABA) level under melatonin pretreatment. The enhanced antioxidative activity was also supported by metabolome assay that melatonin pretreatment increased the levels of non-enzymatic antioxidant organic acids and amino acids. The results demonstrated that exogenous melatonin can enhance rice seed tolerance to salinity during germination via activating antioxidants and modulating phytohormones.

Cyclic GMP-AMP synthase (cGAS) serves as a DNA sensor for recognizing and binding microbial or self-DNA molecules in cells. Upon binding DNA, cGAS produces the second messenger cGAMP to activate the stimulator of interferon genes (STING), which mediates the expression of type 1 interferons (IFN-I) and other cytokines. cGAS-STING-mediated signal pathway plays an important role in innate immune reaction against microbial infections as well as autoimmunity, tumor immunology, and cellular senescence. During this process, cGAS regulates DNA damage repair and induces STING-mediated NF-κB and MAPK signal pathways in autophagy and lysosome-dependent cell apoptosis. However, the molecular mechanisms of cGAS-STING-mediated autophagy still need to be explored. Here, we found that cGAS-STING promotes autophagy by influencing multiple autophagy-related signal pathways: First, cGAS-STING promotes autophagy by inhibiting the mTOR signaling pathway; Second, cGAS-STING affects autophagy by regulating autophagy-related proteins that are also involved in cGAS-STING-mediated IFN-I and NF-κB signaling pathways; Third, the Bcl2 can interact with cGAS and STING to induce cGAS-STING-mediated up-regulation of IFN-I signaling pathway and down-regulation of NF-κB. In addition, we also found that USP19 can significantly reduce the K11-linked ubiquitination of STING in the process of autophagy. Our findings unveiled the functional role and the mechanism of cGAS-STING signaling in regulating autophagy.

To investigate the effect of the erbium:yttrium:aluminum garnet (Er:YAG) laser on enamel re-bonding properties. 80 complete premolars and third molars were selected, after treatment, 120 failed ena...

The left-behind children (LBC), separated from their mother/father or parents for a long period of time, have long been discussed as a subject of concern in China. Existing research has concluded that rural children who did not migrate with parents are subject to emotional risks. In the present study, the purpose is to study the impact of parental migration on early emotional understanding. Purposeful sampling was used to recruit 180 children aged five to six years in rural areas of Guangdong province, including LBC and non-left-behind children (NLBC). Their level of emotional understanding (EU) was assessed by the emotional comprehension test (TEC) adapted to the Chinese context. The results showed that, on the three levels (External, Internal, Reflective) of emotional understanding, LBC aged five- to six- years old scored significantly lower than NLBC as counterparts. On the whole, the emotional comprehension ability of preschool LBC was significantly lower than that of NLBC. However, there were no significant differences within LBC nurtured by single parents, grandparents, and other relatives. This study confirmed that parental migration in early childhood considerably impacted rural LBC’s emotional understanding and affectional adjustment, which provided a significant basis for increasing parental care and early childhood companionship in rural areas.

The powder compact was directly sintered by a pack boriding process to prepare a Fe-based material having a boride layer. The boriding process was carried out at 850 °C, 950 °C and 1050 °C for 3, 5...

Seed moisture at harvest is a critical trait affecting maize quality and mechanized production, and is directly determined by the dehydration process after physiological maturity. However, the dynamic nature of seed dehydration leads to inaccurate evaluation of the dehydration process by conventional determination methods. Seed dry weight and fresh weight were recorded at 14 time points after pollination in a recombinant inbred line (RIL) population derived from two inbred lines with contrasting seed dehydration dynamics. The dehydration curves of RILs were determined by fitting trajectories of dry weight accumulation and dry weight/fresh weight ratio change based on a logistic model, allowing the estimation of eight characteristic parameters that can be used to describe dehydration features. Quantitative trait locus (QTL) mapping, taking these parameters as traits, was performed using multiple methods. Single-trait QTL mapping revealed 76 QTL associated with dehydration characteristic parameters, of which the phenotypic variation explained (PVE) was 1.03% to 15.24%. Multiple-environment QTL analysis revealed 21 related QTL with PVE ranging from 4.23% to 11.83%. Multiple-trait QTL analysis revealed 58 QTL, including 51 pleiotropic QTL. Combining these mapping results revealed 12 co-located QTL and the dehydration process of RILs was divided into three patterns with clear differences in dehydration features. These results not only deepen general understanding of the genetic characteristics of seed dehydration but also suggest that this approach can efficiently identify associated genetic loci in maize. Keywords: Maize, Dehydration, Logistic model, Characteristic parameter, QTL

The growing transportation risk of hazardous materials (hazmat) is an important threat to public safety. As an efficient and reliable mode of transportation, the multimodal hub-and-spoke transport network helps to achieve economies of scale and reduce costs. Considering the dual goals of risk and cost management of hazmat transportation, a novel optimization model of a multimodal hub-and-spoke network with detour (MHSNWD) for hazmat on the strategic level is designed. It integrates the planning of hub location and route selection based on the risk quantification for different transportation modes. Additionally, a detour strategy is applied, which allows for more than two hub nodes to be selected to form an optimal path between any supply and demand nodes in a hub-and-spoke network. Then, the risk is taken as the main objective and the cost is converted into a budget constraint to solve the model by using CPLEX. Additionally, a numerical study is conducted based on a CAB dataset to find the influence of the number of hubs and budget constraints on the optimization results. In addition, a counterpart model of the multimodal hub-and-spoke network without detour (MHSNOD) is tested to validate the advantages of the proposed model of MHSNWD. The numerical experiment shows that an appropriate increase in the number of hubs and the cost budget can remarkably reduce network risk. Compared with MHSNOD, the optimal result of MHSNWD can achieve a marginal improvement in risk reduction. This work may provide an informative decision-making reference for planning a hazmat transportation network.

Xiaonan Zhang,1,* Huimin Fang,1,* Zhigang Zeng,1 Kaijun Zhang,1 Zhanyi Lin,1,2 Gang Deng,1 Weiping Deng,1 Lichang Guan,1 Xuebiao Wei,1 Xinyi Li,2 Lei Jiang,1– 3 Lishu Xu1– 3 1Guangdong Provincial Geriatrics Institute, Guangdong Provincial People’s Hospital, Guangdong Academy of Medical Sciences, Guangzhou, 510080, People’s Republic of China; 2School of Medicine, South China University of Technology, Guangzhou, 510641, People’s Republic of China; 3The Second School of Clinical Medicine, Southern Medical University, Guangzhou, 510515, People’s Republic of China*These authors contributed equally to this workCorrespondence: Lei Jiang; Lishu Xu Tel +86-20-83827812; +86-20-13660032429Email jianglei@smu.edu.cn; xulishu70@163.comPurpose: Gastric cancer is a common tumor type associated with nutritional and immune status. The aim of the current study was to investigate the prognostic value of a preoperative prognostic nutritional index (PNI), composed of nutritional factors and immune factors in elderly patients undergoing gastric cancer surgery.Patients and Methods: A total of 454 patients undergoing gastric cancer surgery were divided into two groups based on preoperative PNI scores: ≤ 45.1 (n = 307) and > 45.1 (n = 147). Survival analysis was performed using the Kaplan–Meier method and Log rank tests. Univariate and multivariate analyses were conducted to identify independent prognostic factors using a Cox proportional hazards model.Results: According to the X-tile program, the optimal cutoff value for predicting overall survival (OS) with the PNI was 45.1. The receiver operating characteristic analysis revealed that PNI exhibited 70.6% sensitivity and 56.5% specificity for predicting death during long-term follow-up. The cumulative incidence of postoperative 4-year mortality indicated that the risk of death increased significantly for PNI ≤ 45.1. In multivariate analysis, preoperative PNI was a significant independent predictor of mortality. In the age-stratified subgroup analysis, preoperative PNI was more sensitive for the old elderly subgroup than for the young elderly subgroup.Conclusion: Preoperative PNI is a sensitive and specific prognostic predictor among elderly patients undergoing gastric cancer surgery.Keywords: elderly patients, gastric cancer, prognostic nutritional index, radical gastrectomy

Seed filling is a dynamic process that determines seed size and nutritional quality. This time-dependent trait follows a logistic (S-shaped) growth curve that can be described by a logistic function, with parameters of biological relevance. When compared between genotypes, the filling dynamics variations are explained by the differences of parameter values; as such, the parameter estimates can be considered as "traits" for genetic analysis to identify loci that are associated with the seed-filling process. We carried out genetic and genomic analysis of the seed-filling process in maize, using a recombinant inbred line (RIL) population derived from the two inbred lines with contrasting seed-filling dynamics. We recorded seed dry weight at 14 time points after pollination, spanning the early filling phases to the late maturation stages. Fitting these data to a logistic model allowed for estimating 12 characteristic parameters that can be used to meaningfully describe the seed-filling process. Quantitative trait locus (QTL) mapping of these parameters identified a total of 90 nonredundant loci. Using bulked segregant RNA-sequencing (BSR-seq) analysis, we identified eight genes that showed differential gene expression patterns at multiple time points between the extreme pools, and these genes co-localize with the mapped QTL regions. Two of the eight genes, GRMZM2G391936 and GRMZM2G008263, are implicated in starch and sucrose metabolism, and biosynthesis of secondary metabolites that are well known for playing a vital role in seed filling. This study suggests that the logistic model-based approach can efficiently identify genetic loci that regulate dynamic developing traits.

We develop a game model for a supply chain consisting of one e-commerce platform, one supplier from other channels, and one retailer. The platform has a well-known brand that can influence consumers’ purchase decisions, and it provides good-quality products with high prices, while supplier from other channels provides cheaper products but possibly with low quality, and there may even be some serious quality problems, sometimes leading to serious problems such as “free-riding” behavior by the retailer and reducing the profits of the supply chain members. First, we study the decisions of platform and retailer under centralized decision (CD) scenario, decentralized decision (DD) scenario, cost sharing contract (CS) scenario, and minimum order quantity contract (QC) scenario. Second, we found that channel conflicts have a negative impact on supply chain members under DD scenario; however, CS and QC scenarios can make the optimal empowerment level of platform the same as CD scenario and encourage retailer to order more products from platform. Finally, the improvement effect in QC and CS scenarios is affected by the substitutability of the two products, the coefficient of empowerment cost, and the reaction coefficient of product price on goodwill. Furthermore, we found that under QC scenario, only within an appropriate range can the platform and the retailer achieve a win-win situation.

Advances in stem cell biology have posed the challenges in revealing the mechanistic themes underlying whole tissues and organs formation during regeneration. The planarian Dugesia japonica is an ideal model organism for the study of regeneration and stem cell biology. However, the genome resources for this species are still limited. Here, we combined single-molecule real-time DNA sequencing platform Pacific Biosciences (PacBio) sequencing, Illumina paired-end sequencing and 10× Genomics linked reads data to obtain the whole-genome sequence of the planarian D. japonica. The final assembled D. japonica genome is 1.13G with contig N50 of 248.44 kb, and scaffold N50 of 652.52 kb. Repeat elements account for 64.92% of the genome, and 12,031 protein coding genes were annotated, of which 10,114 genes had at least one functional annotation, representing 84.07% of the total genes. We present a highly contiguous genome assembly of D. japonica. The D. japonica genome assembly, together with gene annotation and transcriptome data provide a valuable resource to investigate molecular mechanism of planarian and stem cell research.

Background Cold, an environmental factor, induces many reproductive diseases. It is known that endothelin (ET) is a potent vasoconstrictor, and cold stress can increase the expression of ET and its receptors. The cold stress rat model was developed to examine two parameters: (1) the effects of cold stress on ovarian and uterine morphology, function, and microvascular circulation and (2) possible mechanisms of ET and its receptors involved in cold stress-induced menstruation disorders. Methods The rat cold stress model was prepared with an ice water bath. The estrous cycle was observed by methylene blue and hematoxylin and eosin (H&E) staining. Serum estradiol 2 (E2), testosterone (T), progesterone (P) were detected by radioimmunoassay. Hemorheology indices were measured. The real-time blood flow of auricle and uterine surfaces was measured. Expressions of CD34 and α-SMA in ovarian and uterine tissues were detected by immunohistochemistry. ET-1 contents in serum were tested, and expressions of ET-receptor types A and B (ET-AR and ET-BR) in ovarian tissues were detected via Western blotting. Results Cold stress extended the estrous cycle, thereby causing reproductive hormone disorder, imbalance of local endothelin/nitric oxide expression, and microcirculation disturbance. Cold-stress led to up-regulation of ET-AR expression and protein and down-regulation of ET-BR expression in rats. Conclusions This study suggests that the reason for cold stress-induced dysfunction in reproductive organs may be closely related to the imbalance of ET-1 and its receptor expressions, leading to microvascular circulation disorders in local tissues.

To investigate the relationship between symptom patterns of cold coagulation and blood stasis (CCBS) and microcirculation disturbance. In addition, we determined the efficacy of modified Wenjing decoction (WJD) for the treatment of CCBS.CCBS was induced in rats with an ice-water bath treatment. The ovarian function, microvascular and circulatory status of reproductive organs, and function of local microvascular endothelial cells (VECs) and vascular smooth muscle cells (VSMCs) were evaluated.Ovarian dysfunction was observed in the rats with CCBS. It was characterized by the presence of an estrous cycle disorder and a decrease in reproductive hormone levels. Microvascular circulation disorders were associated with an imbalance in vasoconstriction, relaxation substances, nitric oxide, abnormal blood flow in whole blood, and decreased blood flow in the auricle and uterus. VECs were damaged, and VSMCs contracted and proliferated in ovarian and uterine tissues.Our findings suggest that the dysfunctional reproductive organs observed in gynecological CCBS may be closely related to the microcirculation disturbance of local tissues, microvascular contraction, and vascular remodeling. Modified WJD can be used to treat CCBS by improving microcirculation in reproductive organs.

Background Melatonin plays important roles in multiple plant developmental processes and stress responses. However, little is known about the role and putative mechanism of exogenous melatonin in regulating rice seed germination under salt stress. Main Body Here, we revealed that the exogenous application of melatonin can significantly promote rice seed germination under salinity. Its putative molecular mechanisms are further investigated through metabolomic and transcriptomic analyses. The results revealed that the phytohormone concentrations in germinating seeds are reprogrammed, the activities of superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) are enhanced, and the total antioxidant capacity under salinity is activated by exogenous melatonin. In addition, rice seeds pre-treated with melatonin exhibit higher concentrations of glycosides than non-treated seeds under salinity. Furthermore, exogenous melatonin alleviates the accumulation of fatty acids under salinity. Genome-wide transcriptomic profiling is used to identify 7160 transcripts which are differentially expressed under salt (NaCl), salt + melatonin (MT100), and control treatments. Pathway and GO enrichment analyses reveal that the genes involved in the response to oxidative stress, hormone metabolism, heme building, mitochondrion, and tricarboxylic acid transformation are altered after melatonin pre-treatment under salinity. Conclusion This study provides evidence for exogenous melatonin increasing rice seed germination under salt stress, mainly through the activation of antioxidants and modulation of metabolic homeostasis.

Objective We aimed to review our experience in the diagnosis and surgical management of patients diagnosed with inferior vena cava leiomyomatosis (IVL). Methods We retrospectively evaluated all patients diagnosed with IVL between 1999 and 2015. Patient demographics, diagnostic imaging, operative techniques, and perioperative outcomes were reviewed. Results Over the study period, 16 patients with an IVL diagnosis were identified. In all patients, the diagnosis was made with ultrasound and magnetic resonance imaging. In 15 patients who underwent operative intervention, we observed three tumor extension routes from the uterus to the inferior vena cava: (i) via the internal iliac vein, (ii) via the ovarian vein, and (iii) via the anterior sacral vein. Complete tumor removal was achieved in all patients who underwent a one-stage operation (12 patients). Among these patients, antegrade tumor extraction from the right atrium was performed in nine patients, and retrograde extraction from iliac veins was performed in three. A two-stage operation with direct tumor transection and resection was necessary in a subset of patients to facilitate complete resection in one patient, and near-complete resection in two patients. Preoperative imaging and intraoperative findings demonstrated four distinct types of gross tumor morphologies: (i) type A solid cast (43.8%), (ii) type B hallow tube-like (12.5%), (iii) type C thread-like (18.7%), and (iv) type D mixed morphology (25%). Types A and B were the easiest tumor types to extract, and types C and D tumors were more difficult to remove given their fragility. Postoperative surgical pathology confirmed the diagnosis of IVL. All patients recovered successfully with no major complications; there were no deaths. One patient early in our experience had an incomplete resection and developed a recurrence that required re-intervention at 26 months from the initial operation. Conclusions IVL can be accurately diagnosed with ultrasound and magnetic resonance imaging. Surgical tumor resection with a one-stage operation can lead to reasonable outcomes and successful cure rates. The surgical plan can be tailored to the type of tumor morphology observed on preoperative imaging.

The origin and evolution of land plants was an important event in the history of life and initiated the establishment of modern terrestrial ecosystems. From water to terrestrial environments, plants needed to overcome the enhanced ultraviolet (UV) radiation and many other DNA-damaging agents. Evolving new genes with the function of DNA repair is critical for the origin and radiation of land plants. In bacteria, the DNA-3-methyladenine glycosylase (MAG) recognizes of a variety of base lesions and initiates the process of the base excision repair for damaged DNA. The homologs of MAG gene are present in all major lineages of streptophytes, and both the phylogenic and sequence similarity analyses revealed that green plant MAG gene originated through an ancient horizontal gene transfer (HGT) event from bacteria. Experimental evidence demonstrated that the expression of the maize ZmMAG gene was induced by UV and zeocin, both of which are known as DNA-damaging agents. Further investigation revealed that Streptophyta MAG genes had undergone positive selection during the initial evolutionary period in the ancestor of land plants. Our findings demonstrated that the ancient HGT of MAG to the ancestor of land plants probably played an important role in preadaptation to DNA-damaging agents in terrestrial environments.

Following a rice or wheat harvest, a large amount of crop residue (straw) is retained in fields. The straw is often incorporated into the soil in order to increase the soil organic carbon storage and to reduce soil erosion. However, it has become apparent that the incorporated straw can significantly alter soil shear properties, which can dramatically affect energy inputs for tilling and other soil management practices. In this study, laboratory-remolded wheat straw-soil samples were compared with field-collected straw-soil samples; we found high correlations for the cohesion (R2=0.9084) and internal friction angle (R2=0.9548) properties of the samples. Shear tests on rice and wheat straw with different moisture content levels clearly demonstrated the relatively higher shear strength of wheat straw compared to rice straw. The cohesion of remolded rice and wheat straw-soil samples exhibited an increasing linear trend with an increase in densities, whereas the internal friction angle data for these samples exhibited a quadratic trend. Overlapping the cohesion curves revealed that the wheat straw-soil and rice straw-soil samples had the same cohesion at a straw density of 0.63%. Similar results were obtained when the internal fraction angle curves overlapped; the resultant point of intersection was observed at a straw density of 0.46%. As a whole, the remolded sample methodology was found suitable to simulate the shear properties of soils sampled directly from fields.

Background Impaired wound healing might be associated with many issues, especially overactive of reactive oxygen species (ROS), deficiency of blood vessels and immature of epidermis. N-acetylcysteine (NAC), as an antioxidant, could solve these problems by inhibiting overreactive of ROS, promoting revascularization and accelerating re-epithelialization. How to deliver NAC in situ with a controllable releasing speed still remain a challenge. Materials and Methods In this study, we combined collagen (Col) with N-acetylcysteine to perform the characteristics of sustained release and chemically crosslinked Col/NAC composite with polyamide (PA) nanofibers to enhance the mechanical property of collagen and fabricated this multi-layered scaffold (PA-Col/NAC scaffold). The physical properties of the scaffolds such as surface characteristics, water absorption and tensile modulus were tested. Meanwhile, the ability to promote wound healing in vitro and in vivo were investigated. Results These scaffolds were porous and performed great water absorption. The PA-Col/NAC scaffold could sustainably release NAC for at least 14 days. After cell implantation, PA-Col/NAC scaffold showed better cell proliferation and cell migration than the other groups. In vivo, PA-Col/NAC scaffolds could promote wound healing best among all the groups. Conclusion The multi-layered scaffolds could obviously accelerate the process of wound healing and exert better and prolonged effects.

Background The heterotrimeric G protein β subunit RGB1 plays an important role in plant growth and development. However, the molecular mechanisms underlying the regulation of rice growth by RGB1 remain elusive. Results Here, the rgb1 mutants rgb1–1 (+ 1 bp), rgb1–2 (− 1 bp), and rgb1–3 (− 11 bp) were isolated using the CRISPR/Cas9 system, and they were arrested at 1 day after germination and ultimately exhibited seedling lethality. The dynamic anatomical characteristics of the embryos of the rgb1 seedlings and WT during early postgermination and according to TUNEL assays showed that the suppressed growth of the rgb1 mutants was caused by cell death. In addition to the limited shoot and root development, the development of the embryo shoot-root axis was suppressed in the rgb1 mutants. RGB1 was expressed mainly in the root epidermal and vascular tissues of the embryo. Moreover, transcript profiling analysis revealed that the expression of a large number of auxin-, cytokinin-, and brassinosteroid-inducible genes was upregulated or downregulated in the rgb1 mutant compared to the wild type during seedling development. Conclusions Overall, the rgb1 mutants provide an ideal material for exploring the molecular mechanism underlying rice seedling formation during early postgermination development by G proteins. Significance statement The heterotrimeric G protein β subunit RGB1 acts as a crucial factor in promoting early postgermination seedling development in rice. Electronic supplementary material The online version of this article (10.1186/s12284-019-0313-y) contains supplementary material, which is available to authorized users.

Colonization of the land by plants was a critical event in the establishment of modern terrestrial ecosystems, and many characteristics of land plants originated during this process, including the emergence of rosette terminal cellulose-synthesizing complexes. Cellulases are non-homologous isofunctional enzymes, encoded by glycosyl hydrolase (GH) gene families. Although the plant GH5_11 gene subfamily is presumed to encode a cell-wall degrading enzyme, its evolutionary and functional characteristics remain unclear. In the present study, we report the evolution of the land plant GH5_11 subfamily, and the functions of its members in terms of cellulase activity, through comprehensive phylogenetic analyses and observation of Arabidopsis mutants. Phylogenetic and sequence similarity analyses reveal that the ancestor of land plants acquired the GH5_11 gene from fungi through a horizontal gene transfer (HGT) event. Subsequently, positive selection with massive gene duplication and loss events contributed to the evolution of this subfamily in land plants. In Arabidopsis and rice, expression of GH5_11 genes are regulated by multiple abiotic stresses, the duplicated genes showing different patterns of expression. The Arabidopsis mutants atgh5_11a and atgh5_11c display low levels of cellulase and endoglucanase activities, with correspondingly high levels of cellulose, implying that the encoded proteins may function as endoglucanases. However, atgh5_11a and atgh5_11c also display an enlarged rosette leaf phenotype, and atgh5_11c is late-flowering under short photoperiods. These observations suggest that plant GH5_11s possess more functions beyond being endonucleases. To summarize, we demonstrate that the ancestor of land plants has acquired GH5_11 gene through HGT, which extends the cellulose degradation complexity. Our investigations illuminate features of part of the molecular framework underlying the origin of land plants and provide a focus on the cellulose degradation pathway.

Table S1. Oligonucleotide primers and probe sequences used. (DOC 113 kb)