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Digital intraoral scanning is a hot topic in the field of oral digital technology. In recent years, digital intraoral scanning has gradually become the mainstream technology in orthodontics, prosthodontics, and implant dentistry. The precision of digital intraoral scanning and the accuracy and stitching of data collection are the keys to the success of the impression. However, the operators are less familiar with the intraoral scanning characteristics, imaging processing, operator scanning method, oral tissue specificity of the scanned object, and restoration design. Thus far, no unified standard and consensus on digital intraoral scanning technology has been achieved at home or abroad. To deal with the problems encountered in oral scanning and improve the quality of digital scanning, we collected common expert opinions and sought to expound the causes of scanning errors and countermeasures by summarizing the existing evidence. We also describe the scanning strategies under different oral impression requirements. The expert consensus is that due to various factors affecting the accuracy of digital intraoral scanning and the reproducibility of scanned images, adopting the correct scanning trajectory can shorten clinical operation time and improve scanning accuracy. The scanning trajectories mainly include the E-shaped, segmented, and S-shaped methods. When performing fixed denture restoration, it is recommended to first scan the abutment and adjacent teeth. When performing fixed denture restoration, it is recommended to scan the abutment and adjacent teeth first. Then the cavity in the abutment area is excavated. Lastly, the cavity gap was scanned after completing the abutment preparation. This method not only meets clinical needs but also achieves the most reliable accuracy. When performing full denture restoration in edentulous jaws, setting markers on the mucosal tissue at the bottom of the alveolar ridge, simultaneously capturing images of the vestibular area, using different types of scanning paths such as Z-shaped, S-shaped, buccal-palatal and palatal-buccal pathways, segmented scanning of dental arches, and other strategies can reduce scanning errors and improve image stitching and overlap. For implant restoration, when a single crown restoration is supported by implants and a small span upper structure restoration, it is recommended to first pre-scan the required dental arch. Then the cavity in the abutment area is excavated. Lastly, scanning the cavity gap after installing the implant scanning rod. When repairing a bone level implant crown, an improved indirect scanning method can be used. The scanning process includes three steps: First, the temporary restoration, adjacent teeth, and gingival tissue in the mouth are scanned; second, the entire dental arch is scanned after installing a standard scanning rod on the implant; and third, the temporary restoration outside the mouth is scanned to obtain the three-dimensional shape of the gingival contour of the implant neck, thereby increasing the stability of soft tissue scanning around the implant and improving scanning restoration. For dental implant fixed bridge repair with missing teeth, the mobility of the mucosa increases the difficulty of scanning, making it difficult for scanners to distinguish scanning rods of the same shape and size, which can easily cause image stacking errors. Higher accuracy of digital implant impressions can be achieved by changing the geometric shape of the scanning rods to change the optical curvature radius. The consensus confirms that as the range of scanned dental arches and the number of data concatenations increases, the scanning accuracy decreases accordingly, especially when performing full mouth implant restoration impressions. The difficulty of image stitching processing can easily be increased by the presence of unstable and uneven mucosal morphology inside the mouth and the lack of relatively obvious and fixed reference objects, which results in insufficient accuracy. When designing restorations of this type, it is advisable to carefully choose digital intraoral scanning methods to obtain model data. It is not recommended to use digital impressions when there are more than five missing teeth.

[Objective] Part of the newly cultivated farmland formed by the “Gully Control and Land Reclamation” project is facing the risk of soil salinization in the loess hilly region. The spatial distribution characteristics of soil water and salt and their influencing factors were studied for preventing and controlling soil salinization, and promoting sustainable utilization of newly cultivated land. [Methods] A typical area of newly cultivated land was selected, and six experimental plots were established along a gully head to the gully mouth, with sampling points numbered sequentially from 1 to 6. The grid method was used to obtain soil samples from the 0—20 and 20—40 cm layers in each plot. The multifractal method was used to analyze the spatial distribution characteristics of soil water and salt. [Results] Soil water content and salt content gradually decreased from the gully head to the gully mouth. The mean soil water contents and salt contents at sampling points 1, 2, and 3 were 17.6% and 0.81 g/kg, respectively, which were 23.0% and 14.1% higher than the respective values at sampling points 4, 5, and 6. Meanwhile, the multifractal parameters D1 of soil water and salt at sampling points 1, 2, and 3 were less than the respective values at sampling points 4, 5, and 6. ΔD values showed the opposite result, indicating that the spatial variability of soil water and salt at sampling points 1, 2, and 3 were higher. The depth of groundwater influence was the main reason for increased accumulation of salt in the surface soil at sampling points 1, 2, and 3 (p

Gas-liquid flow (GLF), especially slug and annular flows in oil and gas gathering and transportation pipelines, become particularly complex inside elbows and can easily exacerbate pipeline corrosion and damage. In this study, FLUENT was used to conduct 3D simulations of slug and annular flow in elbows for different velocities to assess the ensuing changes in terms of pressure. In particular, the multifluid VOF (Volume of Fraction) model was chosen. The results indicate that under both slug and annular flow conditions, the pressure inside the elbow is lower than the outside. As the superficial velocity of liquid and gas increase, the pressure and liquid flow velocity at different positions of the elbow also increase, while the secondary flow weakens. Under annular flow conditions, the liquid film on the outer side of the elbow is thicker than that on the inner side, and the liquid velocity in the main liquid film zone is the lowest. [ABSTRACT FROM AUTHOR]

The vertical root distribution and rooting depth are the main belowground plant functional traits used to indicate drought resistance in arid and semiarid regions. The effects of the slope aspect on the aboveground traits are visible but not the belowground deep root traits. We aimed to investigate the fine root traits of the locust tree (Robinia pseudoacacia L.) planted on southerly and northerly aspects, and the variations in the rooting depth in regions with different rainfall, as well as assessing how deep rooting, might affect the response to drought in a loess region. We selected three study sites with different rainfall amounts, with six sampling plots at each site (three each with southerly and northerly aspects). Soil core samples were collected down to the depth where no roots were present. The locust trees tended to develop deeper fine roots rather than greater heights. The tree height and diameter were greater for locust trees on northerly aspects, whereas trees on southerly aspects had significantly deeper rooting depths. Fine root traits (root length, root area, and root dry weight density) were higher in the southerly aspect for both Changwu and Ansai, but lower in Suide. The ratio of the root front depth tree height ranged from 1.04 to 3.17, which was higher on southerly than northerly aspects, and it increased as the rainfall decreased. Locust tree growth traits (belowground fine root and aboveground tree height) were positively correlated with the mean annual rainfall. The soil moisture content of the topsoil decreased as the rainfall decreased, but the pattern varied in the deep layer. Our results suggest that the variations in the belowground rooting depth under different slope aspects may be related to plant survival strategies. The vertical extension of the rooting depth and tree height may be key functional traits that determine plant growth in drought-prone regions.

Myricaria laxiflora , which grows along the Yangtze River in China, holds ornamental, ecological, and medicinal value. However, its wild population is threatened and currently designated protected as a national priority. The present research was the first to sequence and assemble M. laxiflora's mitochondrial genome and examine its structural characteristics and phylogenetic relationships with other sequenced Caryophyllales species. The mitochondrial double-stranded closed-ring genome of M. laxiflora was found to be 389,949 bp in length, containing numerous repetitive sequences and RNA editing sites, with 34 protein encoding, 21 tRNA, and 3 rRNA genes. Although there are 22 fragments in the mitochondrial genome of M. laxiflora that are homologous to its chloroplast genome, they are incomplete gene fragments. Phylogenetic analysis demonstrated evolutionary associations with related populations and was in agreement with findings on the chloroplast genome. These findings not only lay a foundation for its preservation but also offer valuable insights for evolutionary analysis and plant breeding research. Supplementary Material Supplementary Material File [ABSTRACT FROM AUTHOR]

Objective: Pyrotinib is a novel EGFR/HER2 dual tyrosine kinase inhibitor developed in China, while its role in neoadjuvant therapy of HER2-positive (HER2+) breast cancer lacks evidence. The current study aimed to explore the efficacy and safety of neoadjuvant pyrotinib plus docetaxel/liposomal doxorubicin/cyclophosphamide (TAC) for HER2+ breast cancer. Methods: A total of 27 HER2+ breast cancer patients received neoadjuvant pyrotinib plus TAC for 6 cycles, then surgery was performed. The clinical and pathological responses, and adverse events were evaluated. Results: Complete response rate, objective response rate, and disease control rate were 0.0%, 44.4% and 100.0% after 2 treatment cycles; 0.0%, 37.0%, and 100.0% after 4 treatment cycles; 37.0%, 37.0%, and 96.3% after 6 treatment cycles; as well as 37.0%, 44.4%, and 100.0% based on the best clinical response. Regarding pathological response, there were 1 (2.7%), 3 (11.1%), 8 (29.6%), 5 (18.5%), and 10 (37.0%) patients realizing Miller-Payne grade (G) 1, G2, G3, G4, and G5, respectively; besides, 10 (37.0%) patients achieved total pathological complete response (pCR), 10 (37.0%) patients realized pCR in breast, and 23 (85.2%) patients achieved pCR in lymph node. Additionally, adverse events included diarrhea (81.5%), dental ulcer (7.4%), and hand-foot syndrome (3.7%); meanwhile, grade 3–4 adverse event consisted of only diarrhea (11.1%). Conclusion: Neoadjuvant pyrotinib plus TAC treatment is efficient and safe in HER2+ breast cancer patients, while further validation is needed. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal fungi (AMF) influence plant nitrogen/phosphorus (N/P) by modifying plant N and P uptake, which further affects plant stoichiometric N/P homeostasis. Plant species and community stoichiometric N/P homeostasis can impact plant species and community stability, respectively, in response to variations of soil N and P availabilities. We investigated interspecific plant interactions via AMF in regard to plant and soil microbial N/P stoichiometry across different soil N and P availabilities induced by N and P addition (0 mg N kg−1, 25 mg N kg−1, 50 mg N kg−1, 30 mg P kg−1 and 100 mg P kg−1). We selected one dominant (Bothriochloa ischaemum; C4 grass) and one subordinate (Lespedeza davurica; legume) species in a natural grassland climax community. We examined how AMF influences stoichiometric N/P homeostasis in monoculture and mixed culture systems, and the resulting consequences for temporal stability of plant species and community in response to variations in soil N and P availability. The AMF mitigated the P limitation of soil microbial communities and decreased the degree of stoichiometric N/P homeostasis of host plants in monoculture. Through their resource‐scavenging and soil organic matter mineralisation functions, AMF enhances plant 'luxury consumption', promoting species stability in monoculture in response to soil N and P availability variations. Compared with plants in monoculture, the interaction between B. ischaemum and L. davurica via AMF increased shoot N/P under soil N‐poor conditions, leading to an enhanced degree of stoichiometric N/P homeostasis in both plant species, especially the legume. Our results suggest that interspecific plant interaction between C4 grass and legume mediated by AMF confers an advantage in complementarity in plant N acquisition under N‐poor conditions, leading to increased stability of plant communities and better maintenance of subordinate species (legume) in response to soil N deficiency. [ABSTRACT FROM AUTHOR]