Microcomputer Aided Selection Of Robot Manipulators

This paper presents two programs for microcomputer aided assessment of the performance of robot manipulators. The first program automatically generates robot models based on user-supplied kinematic parameters. The program also derives a kinematic model that relates the motion of manipulator end-effector to the motion of the joints using the inverse kinematic approach. The approach uses a robust inversion technique that can handle singular conditions as well as joint redundancy. A user can optionally select evaluation of kinematic capabilities of the robot manipulator, such as the ability of the end-effector to reach a specified position and orientation in space or the evaluation of the work space. The second program generates dynamic variables, such as forces and torques, based on user-supplied dynamic parameters and equations of motion of the various joints. Both programs are written for implementation on personal computers. Several runs were carried out to demonstrate the capability and execution times of the two program

Dynamic Analysis Of A Novel Manpowered Transportation Vehicle With High Mechanical Efficiency

This paper evaluates the dynamics of a novel manpowered transportation vehicle. The vehicle has a novel mechanism that maximizes the mechanical input work and utilizes the weight of the rider for propulsion. The rider applies reciprocating stepping linear forces to drive chain and ratchet mechanism. The later transfer the reciprocating motion into a unidirectional rotational motion at the rear wheel to propel the vehicle. We analyzed the dynamics of the driving and transmission mechanism and derived the equations of motion, at first. Then, we evaluated the performance of the vehicle. Results show significant advantages of the novel driving mechanism

Flat Cosmology with Coupled Matter and Dark Energies

Three models of a flat universe of coupled matter and dark energies with different low-redshift parameterizations of the dark energy equation of state are considered. The dark energy is assumed to vary with time like the trace of the energy-momentum tensor of cosmic matter. In the radiation-dominated era the models reduce to standard cosmology. In the matter-dominated era they are, for modern values of the cosmological parameters, consistent with data from SNe Ia searches and with the data of Gurvits et al.(1999)for angular sizes of ultra compact radio sources. We find that the angular size-redshift tests for our models offer a higher statistical confidence than that based on SNe Ia data. A comparison of our results with a recent revised analysis of angular size-redshift legacy data is made,and the implications of our models with optimized relativistic beaming in the radio sources is discussed. In particular we find that relativistic beaming implies a Lorentz factor less than 6,in agreement with its values for powerful Active Galactic Nuclei.Comment: Version to appear in The Astronomical Journal, with a modified name- Flat Cosmology with Coupled Matter and Dark Energies. Expanded and Modified conten

Synthesis and Biological activity of 1,3-Thiazolylidenehydrazinylidene ethylpyridiniumbromide monohydrate, 1,3-Thiazolylidenehydraziniumbromide and 1,3-Thiazolylidenehydrazine derivatives

1,3-Thiazolylidenehydrazinylidene ethylpyridinium bromide monohydrate, 1,3-thiazolylidenehydrazinium bromide and 1,3-thiazolylidenehydrazine derivatives were synthesized by heterocyclization of 2-(1-substituted ethylidene) hydrazinecarbothioamides, characterized and screened for their anti-bacterial activities. The structures of synthesized compounds were established by spectroscopic (IR, 1H, 13C-NMR, Mass) and X-ray analyses

Differential roles of EPS8 in carcinogenesis: Loss of protein expression in a subset of colorectal carcinoma and adenoma

Peer reviewe

The Burkholderia Cenocepacia OmpA-Like Protein BCAL2958: Identification, Characterization, and Detection of Anti-BCAL2958 Antibodies in Serum from B. Cepacia Complex-Infected Cystic Fibrosis Patients

Respiratory infections by bacteria of the Burkholderia cepacia complex (Bcc) remain an important cause of morbidity and mortality among cystic fibrosis patients, highlighting the need for novel therapeutic strategies. In the present work we have studied the B. cenocepacia protein BCAL2958, a member of the OmpA-like family of proteins, demonstrated as highly immunogenic in other pathogens and capable of eliciting strong host immune responses. The encoding gene was cloned and the protein, produced as a 6× His-tagged derivative, was used to produce polyclonal antibodies. Bioinformatics analyses led to the identification of sequences encoding proteins with a similarity higher than 96 % to BCAL2958 in all the publicly available Bcc genomes. Furthermore, using the antibody it was experimentally demonstrated that this protein is produced by all the 12 analyzed strains from 7 Bcc species. In addition, results are also presented showing the presence of anti-BCAL2958 antibodies in sera from cystic fibrosis patients with a clinical record of respiratory infection by Bcc, and the ability of the purified protein to in vitro stimulate neutrophils. The widespread production of the protein by Bcc members, together with its ability to stimulate the immune system and the detection of circulating antibodies in patients with a documented record of Bcc infection strongly suggest that the protein is a potential candidate for usage in preventive therapies of infections by Bcc

Thermodynamics of Decaying Vacuum Cosmologies

The thermodynamic behavior of vacuum decaying cosmologies is investigated within a manifestly covariant formulation. Such a process corresponds to a continuous irreversible energy flow from the vacuum component to the created matter constituents. It is shown that if the specific entropy per particle remains constant during the process, the equilibrium relations are preserved. In particular, if the vacuum decays into photons, the energy density $\rho$ and average number density of photons $n$ scale with the temperature as $\rho \sim T^{4}$ and $n \sim T^{3}$. The temperature law is determined and a generalized Planckian type form of the spectrum, which is preserved in the course of the evolution, is also proposed. Some consequences of these results for decaying vacuum FRW type cosmologies as well as for models with ``adiabatic'' photon creation are discussed.Comment: 21 pages, uses LATE

Synthesis of New Fluorine Substituted Heterocyclic Nitrogen Systems Derived from p-Aminosalicylic Acid as Antimycobacterial Agents

Some new fluorine substituted heterocyclic nitrogen systems 2-17 have been synthesized from ring closure reactions of substituted p-amino salicylic acids (PAS). The Schiffs base of PAS was cyclized with chloroacetyl chloride and mercaptoacetic acid to give azetidinone 2, thiazolidinone 3, and spiro-fluoroindolothiazoline-dione 10. However, PAS when reacted directly with 4-fluorobenzoyl chloride and 5-oxazolinone yielded derivatives 4, 5, and 7. Aminomethylation of PAS using formaldehyde and piperidine or piperazine formed N-alkyl and N,N -dialkyl derivatives (11 and 12 respectively) upon fluorinated benzoylation gave compounds 13 and 14. Similarly, treatment of PAS with thiosemicarbazide 15 and subsequent cyclization with diethyl oxalate yielded the fluorinated heterocycle 17. The structures of the fluorinated heterocyclic systems have been established on the basis of elemental analysis, 1 H NMR, 13 C NMR, and MS spectral data. Some of the targets exhibited a high inhibition towards Mycobacterium strain with favorable log P values

Causal Bulk Viscous Dissipative Isotropic Cosmologies with Variable Gravitational and Cosmological Constants

We consider the evolution of a flat Friedmann-Robertson-Walker Universe, filled with a causal bulk viscous cosmological fluid, in the presence of variable gravitational and cosmological constants. The basic equation for the Hubble parameter, generalizing the evolution equation in the case of constant gravitational coupling and cosmological term, is derived, under the supplementary assumption that the total energy of the Universe is conserved. By assuming that the cosmological constant is proportional to the square of the Hubble parameter and a power law dependence of the bulk viscosity coefficient, temperature and relaxation time on the energy density of the cosmological fluid, two classes of exact solutions of the field equations are obtained. In the first class of solutions the Universe ends in an inflationary era, while in the second class of solutions the expansion of the Universe is non-inflationary for all times. In both models the cosmological "constant" is a decreasing function of time, while the gravitational "constant" increases in the early period of evolution of the Universe, tending in the large time limit to a constant value.Comment: 14 pages, 15 figure

Gradients of orientation, composition and hydration of proteins for efficient light collection by the cornea of the horseshoe crab

The lateral eyes of the horseshoe crab, Limulus polyphemus, are the largest compound eyes within recent Arthropoda. While this visual system has been extensively described before, the precise mechanism allowing vision has remained controversial. Correlating quantitative refractive index (RI) mapping and detailed structural analysis, we demonstrate how gradients of RI in the cornea result from the hierarchical organization of chitin-protein fibers, heterogeneity in protein composition and bromine doping, as well as spatial variation in water content. Combining the realistic cornea structure and measured RI gradients with full-wave optical modelling and ray-tracing approaches, we show that the light collection mechanism depends on both refraction-based graded index (GRIN) optics and total internal reflection. The optical properties of the cornea are governed by different mechanisms at different hierarchical levels, demonstrating the remarkable versatility of arthropod cuticle.One-sentence summary Structural hierarchy and protein hydration determine the optical performance of the cornea of L. polyphemus.Competing Interest StatementTS and MAKAR are employed by TELIGHT. All other authors declare that they have no competing interests