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关键词： abscisic acid signalling   age inducible Crassulacean acid metabolism   Crassulacean acid metabolism (CAM)   drought stress   genomics   Nanopore sequencings   transcriptomics  

摘要： Despite the increasing number of well-studied plant species with well-annotated genomes across plant life, there are few densely sampled genera with more than a couple of genome sequences representing the diversity of whole genera. Here, we develop an economic approach to full-genome sequencing that could be used to sequence many species within a genus. We made use of the Nanopore rapid sequencing kit to assist in plant genome assembly, dramatically reducing the cost. Here we applied this method to cost-effectively develop genomic resources for Kalancho & euml;blossfeldiana, a commercially important ornamental, in which Crassulacean Acid Metabolism (CAM), a water-conserving mode of photosynthesis can be induced. We present a physiological and biochemical characterisation of Kalanchoe blossfeldiana with its nuclear and chloroplastic genome and a comparative C3, CAM dusk transcriptome. We apply this approach to a complex tetraploid genome, making use of a relative species for chromosomal scaffolding to reduce assembly ploidy, we provide a resource for future gene expression studies. We highlight its limitations, e.g. the need for deeper sequencing to accurately resolve genome structure and haplotypes without using a relative species for scaffolding. T he study demonstrates the merits of K. blossfeldiana as a comparative system for studying C3 and CAM within a plant and has identified substantial changes in the dusk transcriptome between young C3 and mature CAM K. blossfeldiana leaves in response to age-induced CAM, and shows that in the absence of abiotic stress, CAM induction still involves the engagement of drought and abscisic acid (ABA) response pathways.

关键词： small-target detection   Yolov5   BiFormer   CAM  

摘要： Small targets exist in large numbers in various fields. They are broadly used in aerospace, video monitoring, and industrial detection. However, because of its tiny dimensions and modest resolution, the precision of small-target detection is low, and the erroneous detection rate is high. Therefore, based on YOLOv5, an improved small-target detection model is proposed. First, in order to improve the number of tiny targets detected while enhancing small-target detection performance, an additional detection head is added. Second, involution is used between the backbone and neck to increase the channel information of feature mapping. Third, the model introduces the BiFormer, wherein both the global and local feature information are captured simultaneously by means of its double-layer routing attention mechanism. Finally, a context augmentation module (CAM) is inserted into the neck in order to maximize the structure of feature fusion. In addition, in order to consider among the required real frame as well as the prediction frame simultaneously, YOLOv5's original loss function is exchanged. The experimental results using the public dataset VisDrone2019 show that the proposed model has P increased by 13.43%, R increased by 11.28%, and mAP@.5 and mAP@[.5:.95] increased by 13.88% and 9.01%, respectively.

关键词： combined shear loading   cylindrical cavity   loading paths   MCC  

摘要： This paper presents an analytical solution for combined vertical and torsional shear loading of a cylindrical cavity in undrained modified Cam-Clay. The governing partial differential equations for the cylindrical cavity are established in the polar coordinate. The problem is formulated as a set of first-order differential equations by using the axisymmetric condition, equilibrium equations, and elastic-plastic constitutive relationship. The influence of the second shear loading on the initial shear strain is considered in the plastic state. Then the stress-strain distributions can be calculated by integrating within the elastic and plastic zones around the cavity. A finite element method simulation of the cavity under combined shear loading is established to verify the proposed approach, and the results are in good agreement with the proposed analytical solution. Parametric analyses are carried out on the effects of clay overconsolidation ratios and in situ stress coefficients under different loading paths and loading ratios. The results show that the combined shear loading on the cavity wall has a significant effect on the stress distribution of the surrounding soil, and the influence of the loading path cannot be neglected.

关键词： aging   CAD/CAM   CAD/CAM materials   dental materials   lithium disilicate   prosthodontics  

摘要： Before clinical trials are initiated, studying the mechanical performance of modern CAD/CAM restorative materials exposed to aging conditions would provide insights on their performance in service. This study evaluated the impact of thermomechanical aging on various resin composite, ceramic, hybrid, and nano-filled resin composite materials after two polymerization modes. Specimens (3 x 4 x 14 mm(3)) were fabricated using (n = 12 per group) a universal composite (Filtek Supreme XTE photo-polymerized for either 40 s or 120 s per layer), hybrid ceramics (BRILLIANT Crios, GC Cerasmart, Lava Ultimate, VITA ENAMIC), glass ceramics (IPS *** CAD, VITA Suprinity PC, Straumann n!ce), or feldspar ceramics (VITABLOCS Mark II, GC Initial LRF). In each group, half of the specimens underwent thermomechanical aging. A three-point bending test was applied to all specimens and the results were statistically analyzed (alpha = 0.05). Glass ceramics and hybrid ceramics presented higher flexural strength values than feldspar ceramics and the universal composite before and after aging (p < 0.05). Thermomechanical cycling affected the flexural strength of all materials (p < 0.05) except Lava Ultimate, Straumann n!ce, and GC Initial (p > 0.05). The highest decrease in flexural strength after aging was found in the universal composite (40 s polymerization) (p < 0.001) and Vita Enamic (p < 0.001), while the lowest decrease was in the hybrid ceramics, Cerasmart and Lava Ultimate (p < 0.05). Extending polymerization duration reduced the aging effect on the universal composite tested. Thermomechanical aging affected the flexural strength of most materials tested. Universal composites and feldspar ceramics presented similar flexural strength values.

关键词： dental materials   CAD-CAM   polymers   resin composites   oral biofilm   indirect restorations  

摘要： Objective: This study aimed to determine the status of the scientific literature on CAD-CAM resin blocks by mapping the available evidence and identifying knowledge gaps. Data/Source: A systematic search of studies investigating CAD-CAM resin blocks was conducted. Risk of bias was assessed, and data on study designs, level of evidence, compositional classification, manufacturer, commercial brand, and properties investigated were extracted. This review followed Arksey and O'Malley's five-stage framework and utilized Medline (OVID), EMBASE, and Scopus (Elsevier) databases. Study Selection: Study selection resulted in 27 studies for data extraction out of 209 studies screened from an initial pool of 529 studies. High sampling bias related to sample size and randomization was observed in almost all studies. Most studies (99%) were conducted in vitro, with low levels of evidence. The most common composition was "nano-ceramic". 3M ESPE was the manufacturer with the most investigated blocks, and their product, 3M (TM) Lava (TM) Ultimate Restorative, was predominant in the selected investigations. Methodological heterogeneity was extensive among the studies, with mechanical properties (38%) and bond strength (35%) being the most commonly investigated outcomes. Conclusion: This scoping review indicates an increasing trend in dental research assessing CAD-CAM resin blocks. However, the overall level of evidence derived from these studies is low, predominantly consisting of in vitro investigations. Clinical Significance: The findings underscore the need for clinical trials to augment the level of evidence and enable long-term assessment of CAD-CAM resin blocks. Dentists should be cautious while interpreting the findings from in vitro studies, as the outcomes may not directly translate to clinical success.

关键词： 2D/3D laser line sensor   profilometry   simulation   point cloud   measurement generation   STL   Matlab  

摘要： The increasing adoption of 2D/3D laser line sensors in industrial and research applications necessitates accurate and efficient simulation tools for tasks such as surface inspection, dimensional verification, and quality control. This paper presents a novel algorithm developed in MATLAB for simulating the measurements of any 2D/3D laser line sensor on STL CAD models. The algorithm uses a modified fast-ray triangular intersection method, addressing challenges such as overlapping triangles in assembly models and incorporating sensor resolution to ensure realistic simulations. Quantitative analysis shows a significant reduction in computation time, enhancing the practical utility of the algorithm. The simulation results exhibit a mean deviation of 0.42 mm when compared to real-world measurements. Notably, the algorithm effectively handles complex geometric features, such as holes and grooves, and offers flexibility in generating point cloud data in both local and global coordinate systems. This work not only reduces the need for physical prototyping, thereby contributing to sustainability, but also supports AI training by generating accurate synthetic data. Future work should aim to further optimize the simulation speed and explore noise modeling to enhance the realism of simulated measurements.

摘要： In the NOTION-3 trial, percutaneous coronary intervention reduced the occurrence of major adverse cardiac events compared with conservative treatment in patients who were undergoing transcatheter aortic valve implantation for severe aortic stenosis and who had stable coronary artery disease.

关键词： Shear Strength   lithium disilicate   recycling  

摘要： Purpose: To investigate the effects of recycling lithium disilicate (LD), surface treatment, and thermocycling on the bond strength to resin cement. Materials and Methods: A total of 72 tablets (10 x 10 x 3 mm) of LD were made according to the recycling cycle with 24 tablets for each strategy: control (conventional sintering), 1R (1 recycling cycle), and 3R (3 recycling cycles). For the recycling groups, tablets were waxed, mounted in a silicone ring, and poured with investment material, and residues of sintered LD tablets were pressed by the lost wax technique. The residual LD was reused as described until it reached 3R. Afterward, the tablets were embedded in acrylic resin, sanded, and divided (n = 15) according to the factors of "surface treatment" (hydrofluoric acid [HF] for 20 seconds [HF20s] and silane, HF for 120 seconds [HF120s] and silane, and Monobond Etch & Prime [MEP]) and thermocycling (TC;with 10,000 cycles and without). After surface treatment, cylinders (diameter: 2 mm) of resin cement were made and submitted to SBS test (100 kgf, 1 mm/minute). Data (MPa) were analyzed by three-way ANOVA, Tukey test (5%), and Weibull analysis. Failure analysis was performed with a stereomicroscope. Results: ANOVA revealed that all factors were significant (P =.000*). The group 3RMEP (105.09 +/- 19.49) presented the highest SBS among the experimental groups. The 1RHF20s(Tc) (7.50 +/- 1.97) group had the lowest SBS, similar to CHF20s(Tc) (15.69 +/- 3.77), 1RHF20s (15.12 +/- 3.03), 1RHF120s(Tc) (14.60 +/- 3.43), and 3RHF20s(Tc)(15.65 +/- 0.97). The Weibull modulus and characteristic strength varied among the experimental groups (P = .0). Failure analysis revealed adhesive and mixed types. Conclusions: The recycling of DL ceramics increases the SBS to resin cement when the ceramic is treated with HF120s and silane or MEP. Intl Prosthodont 2024;37:675-685. doi: 10.11607fijp.8677

关键词： CAD   coupling information   entropy   recurrence plot   CNN   feature selection  

摘要： Early and highly precise detection is essential for delaying the progression of coronary artery disease (CAD). Previous methods primarily based on single-modal data inherently lack sufficient information that compromises detection precision. This paper proposes a novel multi-modal learning method aimed to enhance CAD detection by integrating ECG, PCG, and coupling signals. A novel coupling signal is initially generated by operating the deconvolution of ECG and PCG. Then, various entropy features are extracted from ECG, PCG, and its coupling signals, as well as recurrence deep features also encoded by integrating recurrence plots and a parallel-input 2-D CNN. After feature reduction and selection, final classification is performed by combining optimal multi-modal features and support vector machine. This method was validated on simultaneously recorded standard lead-II ECG and PCG signals from 199 subjects. The experimental results demonstrate that the proposed multi-modal method by integrating all signals achieved a notable enhancement in detection performance with best accuracy of 95.96%, notably outperforming results of single-modal and joint analysis with accuracies of 80.41%, 86.51%, 91.44%, and 90.42% using ECG, PCG, coupling signal, and joint ECG and PCG, respectively. This indicates that our multi-modal method provides more sufficient information for CAD detection, with the coupling information playing an important role in classification.