Isolation, Structural Elucidation and Structure-Activity Studies of Natural Products From Regional Plants of the Asteraceae.

In a biochemical systematic study of the plant family Asteraceae combined with a search for bioactive natural products, the isolation and structural elucidation of secondary metabolites from seven plant species is reported. Investigation of the roots of Solidago canadensis provided six known and one new clerodane diterpenes related to kolavenic acid and five known matricaria ester-type polyacetylenes. The roots and aerial parts of Solidago rugosa afforded the known diterpenes kolavenol, hardwickiic acid, ($-$)-kaur-16-en-19-oic acid, (+)-manool, (+)-3$\beta$-hydroxymanool, manoyl oxide and ent-abietic acid and the new labdane diterpene, (+)-18-tigloyloxymanool, plus four new ent-abietane diterpenes. The isolation of two new and eight known eudesmane-type sesquiterpene cinnamates, and benzyl 2,6-dimethoxybenzoate from the roots of Brintonia discoidea (syn. Solidago discoidea) is reported. The roots of Chrysoma pauciflosculosa (syn. Solidago pauciflosculosa) provided the known polyacetylenes cis,cis- and cis,trans-matricaria esters, a mixture of two isomeric epoxides of matricaria ester, and two known triterpenes, epifriedelinol and friedelin. In addition, the ubiquitous 2,6-dimethoxybenzoquinone and a new benzotropolone were found. The roots of Erigeron philadelphicus afforded, besides the above four polyacetylenes, two isomeric matricaria lactones. The roots of giant ragweed (Ambrosia trifida) afforded thiarubrine B and its related thiophene, as well as a new 1,2-dithia-3,5-cyclohexadiene derivative, 3-(pent-3-yn-1-ynyl)-6-(3,4-epoxy-but-1-ynyl)-1,$2$ -dithiacyclohexa-3,5-diene. The stems of A. trifida gave, besides $\beta$-cubebene and $\alpha$-farnesene, two carotane-type sesquiterpenes, the known lasidiol angelate (1$\alpha$-angeloyloxycarotol) and the new 1$\alpha$-(2\sp\prime-methylbutyroyloxy)-carotol, plus 2,6-dimethoxybenzoquinone and hexadecanal. The aerial parts of Liatris ohlingerae afforded five known and two new heliangolide-type sesquiterpene lactones related to liscunditrin and four known triterpenes, taraxasterol, pseudo-taraxasterol and their acetates. The detailed structure elucidation using spectroscopic methods and chemical transformations is described. In order to demonstrate structure-activity relationships, a series of chemical transformations on sesquiterpene lactones were performed. Epoxidation of costunolide yielded 1,10-epoxycostunolide, parthenolide, and the cyclization products santamarin, reynosin, magnolialide and a 1,4-epoxyeudesmenolide. Reduction of santamarin afforded 11,13-dihydrosantamarin and an eudesmen-triol, while reduction of reynosin provided 11,13-dihydroreynosin and two eudesman-triols. The acid-catalyzed transformation of dihydroparthenolide in methanol afforded two guaianolide derivatives. These sesquiterpenes were tested against Mycobacterium tuberculosis and M. avium and the structure-activity relationships among sesquiterpene lactones are discussed. Polyacetylenes from S. canadensis, C. pauciflosculosa and E. philadelphicus also exhibited significant activity against these two strains of mycobacteria

State Generation Method for Humanoid Motion Planning Based on Genetic Algorithm

A new approach to generate the original motion data for humanoid motion planning is presented in this paper. And a state generator is developed based on the genetic algorithm, which enables users to generate various motion states without using any reference motion data. By specifying various types of constraints such as configuration constraints and contact constraints, the state generator can generate stable states that satisfy the constraint conditions for humanoid robots. To deal with the multiple constraints and inverse kinematics, the state generation is finally simplified as a problem of optimizing and searching. In our method, we introduce a convenient mathematic representation for the constraints involved in the state generator, and solve the optimization problem with the genetic algorithm to acquire a desired state. To demonstrate the effectiveness and advantage of the method, a number of motion states are generated according to the requirements of the motion

Trajectory planning of jumping over an obstacle for one-legged jumping robot

For one-legged passive jumping robot, a trajectory planning strategy is developed to jump over an obstacle integrating three various dynamics among jumping process. Manipulability ellipsoids are effective tools to perform task space analysis and motion optimization of redundant manipulators. Jumping robot can be considered as a redundant manipulator with a load held at the end-effector. The concept of inertia matching ellipsoid and directional manipulability is extended to optimize the take-off posture of jumping robot, and the optimized results have been used to plan jumping trajectory. Aimed at the sensitivity of a trajectory to constraint conditions on point-to-point motion planning, the 6th order polynomial function is proposed to plan jumping motion having a better robustness to the parameters change of constraint conditions than traditional 5th order polynomial function. In order to lift the foot over the obstacle, correction functions are constructed under unchanged boundary constraint conditions. Furthermore, the body posture is controlled based on internal motion dynamics and steady-state consecutive jumping motion principle. A prototype model is designed, and the effectiveness of the proposed method is confirmed via simulations performed on parameters of designed prototype

DPHL: A DIA Pan-human Protein Mass Spectrometry Library for Robust Biomarker Discovery

To address the increasing need for detecting and validating protein biomarkers in clinical specimens, mass spectrometry (MS)-based targeted proteomic techniques, including the selected reaction monitoring (SRM), parallel reaction monitoring (PRM), and massively parallel data-independent acquisition (DIA), have been developed. For optimal performance, they require the fragment ion spectra of targeted peptides as prior knowledge. In this report, we describe a MS pipeline and spectral resource to support targeted proteomics studies for human tissue samples. To build the spectral resource, we integrated common open-source MS computational tools to assemble a freely accessible computational workflow based on Docker. We then applied the workflow to generate DPHL, a comprehensive DIA pan-human library, from 1096 data-dependent acquisition (DDA) MS raw files for 16 types of cancer samples. This extensive spectral resource was then applied to a proteomic study of 17 prostate cancer (PCa) patients. Thereafter, PRM validation was applied to a larger study of 57 PCa patients and the differential expression of three proteins in prostate tumor was validated. As a second application, the DPHL spectral resource was applied to a study consisting of plasma samples from 19 diffuse large B cell lymphoma (DLBCL) patients and 18 healthy control subjects. Differentially expressed proteins between DLBCL patients and healthy control subjects were detected by DIA-MS and confirmed by PRM. These data demonstrate that the DPHL supports DIA and PRM MS pipelines for robust protein biomarker discovery. DPHL is freely accessible at https://www.iprox.org/page/project.html?id=IPX0001400000

Dynamics Analysis of Close-coupling Multiple Helicopters System

AbstractThe particularity and practicality of harmony operations of close-coupling multiple helicopters indicate that the researches on it are urgent and necessary. Using the model that describes two hovering helicopters carrying one heavy load, an inertia coordinate system and body coordinate systems of each sub-system are established. A nonlinear force model is established too. The equilibrium computation results can be regarded as the reference control inputs of the flight control system under hovering or low-speed flight condition. After the establishment of a translation kinematics model and a posture kinematics model, a coupling dynamics model of the multiple helicopter system is set up. The results can also be regarded as the base to analyze stabilization and design a controller for a close-coupling multiple helicopters harmony operation system

State Generation Method for Humanoid Motion Planning Based on Genetic Algorithm

A new approach to generate the original motion data for humanoid motion planning is presented in this paper. And a state generator is developed based on the genetic algorithm, which enables users to generate various motion states without using any reference motion data. By specifying various types of constraints such as configuration constraints and contact constraints, the state generator can generate stable states that satisfy the constraint conditions for humanoid robots.To deal with the multiple constraints and inverse kinematics, the state generation is finally simplified as a problem of optimizing and searching. In our method, we introduce a convenient mathematic representation for the constraints involved in the state generator, and solve the optimization problem with the genetic algorithm to acquire a desired state. To demonstrate the effectiveness and advantage of the method, a number of motion states are generated according to the requirements of the motion

Study on State Transition Method Applied to Motion Planning for a Humanoid Robot

This paper presents an approach of motion planning for a humanoid robot using a state transition method. In this method, motion planning is simplified by introducing a state-space to describe the whole motion series. And each state in the state-space corresponds to a contact state specified during the motion. The continuous motion is represented by a sequence of discrete states. The concept of the transition between two neighboring states, that is the state transition, can be realized by using some traditional path planning methods. Considering the dynamical stability of the robot, a state transition method based on search strategy is proposed. Different sets of trajectories are generated by using a variable 5th-order polynomial interpolation method. After quantifying the stabilities of these trajectories, the trajectories with the largest stability margin are selected as the final state transition trajectories. Rising motion process is exemplified to validate the method and the simulation results show the proposed method to be feasible and effective