7-(3-Nitro­phen­yl)-9,10-dihydro-7H-benzo[h]cyclo­penta­[b]quinolin-8(11H)-one

In the title compound, C22H16N2O3, the naphthalene ring, the 1,4-dihydro­pyridine ring and the cyclo­pent-2-enone ring are nearly coplanar, with the dihedral angles between the neighbouring rings being 1.93 (11) and 2.30 (9)°, respectively. The benzene ring group at position 7 and the 1,4-dihydro­pyridine ring form a dihedral angle of 78.75 (4)°. Inter­molecular N—H⋯O hydrogen bonds and C—H⋯π inter­actions stabilize the crystal packing

Kinematics and stiffness of a planar tensegrity parallel mechanism

In this work, the kinematics and stiffness of a planar tensegrity parallel mechanism are investigated. The analytical solutions to the forward and reverse kinematics were found using an energy method. The singular configurations and workspaces were detailed. Afterwards, the stiffness of the mechanism was analyzed. It is demonstrated that the stiffness is at a local maximum when the mechanism is in stable equilibrium and at a local minimum when the mechanism is in unstable equilibrium. The stiffness distributions are approximately symmetric about a certain line inside the actuator and Cartesian workspaces. Large values of the actuator length should be selected for high stiffness applications. The singular configurations, workspaces and stiffness variations inside the actuator and Cartesian workspaces lay a foundation for the use of the mechanism

Study on the Collaborative Design PN-PDDP Model for the Multi-component Coupling Rotor System Based on Petri Nets

AbstractBased on the analysis of the characteristics for the design process in the complex multi-component coupling rotor system, and considering the fact that the multi-components co-design is demanded in the design process of the performance-driven target coupled rotor system, a PN-PDDP (Petri Network for Performance Driven Design Process) model based on the extended Petri nets is presented. The model defines the libraries of the performance and structure characteristics, the traces Token and firing rules. With the model, the flow process of the various coupled information flow is described, and the conflict resolution mechanism for the conflict information is developed. The model also offers guidance on the construction of the related database and design platform, which will provide the important design tools and implementation means for the design of the multi-component coupling turbopump rotor system in the liquid rocket engine

4-(4-Bromo­phen­yl)-3-methyl-1-phenyl-6,7-dihydro-1H-pyrazolo­[3,4-b]thieno[2,3-e]pyridine 5,5-dioxide

In the title compound, C21H16BrN3O2S, the pyrazole and pyridine rings are nearly coplanar, the dihedral angle between their planes being 3.17 (14)°. The 2,3-dihydro­thio­phene ring adopts an envelope conformation. The 4-bromo­phen­yl/pyridine ring and phen­yl/pyrazole rings form dihedral angles of 60.06 (9) and 33.49 (11)°, respectively. There is an intra­molecular C—H⋯N hydrogen bond. The crystal packing is stabilized by inter­molecular C—H⋯O hydrogen bonding and C—H⋯π inter­actions

Kinematics and Dynamics of a Tensegrity-Based Water Wave Energy Harvester

A tensegrity-based water wave energy harvester is proposed. The direct and inverse kinematic problems are investigated by using a geometric method. Afterwards, the singularities and workspaces are discussed. Then, the Lagrangian method was used to develop the dynamic model considering the interaction between the harvester and water waves. The results indicate that the proposed harvester allows harvesting 13.59% more energy than a conventional heaving system. Therefore, tensegrity systems can be viewed as one alternative solution to conventional water wave energy harvesting systems

Kinematics, Singularity, and Workspaces of a Planar 4-Bar Tensegrity Mechanism

Compared with conventional mechanisms, tensegrity mechanisms have many attractive characteristics such as light weight, high ratio of strength to weight, and accuracy of modeling. In this paper, the kinematics, singularity, and workspaces of a planar 4-bar tensegrity mechanism have been investigated. Firstly, the analytical solutions to the forward and inverse kinematic problems are found by using an energy based method. Secondly, the definition of a tensegrity mechanism’s Jacobian is introduced. As a consequence, the singularity analysis of the planar 4-bar tensegrity mechanism has been completed. Thirdly, the actuator and output workspaces are mapped. Finally, some attractive characteristics of the mechanism are concluded

Detecting the QTL-Allele System of Seed Oil Traits Using Multi-Locus Genome-Wide Association Analysis for Population Characterization and Optimal Cross Prediction in Soybean

Soybean is one of the world's major vegetative oil sources, while oleic acid and linolenic acid content are the major quality traits of soybean oil. The restricted two-stage multi-locus genome-wide association analysis (RTM-GWAS), characterized with error and false-positive control, has provided a potential approach for a relatively thorough detection of whole-genome QTL-alleles. The Chinese soybean landrace population (CSLRP) composed of 366 accessions was tested under four environments to identify the QTL-allele constitution of seed oil, oleic acid and linolenic acid content (SOC, OAC, and LAC). Using RTM-GWAS with 29,119 SNPLDBs (SNP linkage disequilibrium blocks) as genomic markers, 50, 98, and 50 QTLs with 136, 283, and 154 alleles (2–9 per locus) were detected, with their contribution 82.52, 90.31, and 83.86% to phenotypic variance, corresponding to their heritability 91.29, 90.97, and 90.24% for SOC, OAC, and LAC, respectively. The RTM-GWAS was shown to be more powerful and efficient than previous single-locus model GWAS procedures. For each trait, the detected QTL-alleles were organized into a QTL-allele matrix as the population genetic constitution. From which the genetic differentiation among 6 eco-populations was characterized as significant allele frequency differentiation on 28, 56, and 30 loci for the three traits, respectively. The QTL-allele matrices were also used for genomic selection for optimal crosses, which predicted transgressive potential up to 24.76, 40.30, and 2.37% for the respective traits, respectively. From the detected major QTLs, 38, 27, and 25 candidate genes were annotated for the respective traits, and two common QTL covering eight genes were identified for further study

Radiomics Signature on Computed Tomography Imaging: Association With Lymph Node Metastasis in Patients With Gastric Cancer

Background: To evaluate whether radiomic feature-based computed tomography (CT) imaging signatures allow prediction of lymph node (LN) metastasis in gastric cancer (GC) and to develop a preoperative nomogram for predicting LN status.Methods: We retrospectively analyzed radiomics features of CT images in 1,689 consecutive patients from three cancer centers. The prediction model was developed in the training cohort and validated in internal and external validation cohorts. Lasso regression model was utilized to select features and build radiomics signature. Multivariable logistic regression analysis was utilized to develop the model. We integrated the radiomics signature, clinical T and N stage, and other independent clinicopathologic variables, and this was presented as a radiomics nomogram. The performance of the nomogram was assessed with calibration, discrimination, and clinical usefulness.Results: The radiomics signature was significantly associated with pathological LN stage in training and validation cohorts. Multivariable logistic analysis found the radiomics signature was an independent predictor of LN metastasis. The nomogram showed good discrimination and calibration.Conclusions: The newly developed radiomic signature was a powerful predictor of LN metastasis and the radiomics nomogram could facilitate the preoperative individualized prediction of LN status