Transmission electron microscopy characterization of microstructural features of Al-Li-Cu alloys

A transmission electron microscopy (TEM) examination of aluminum-lithium-copper alloys was conducted. The principal purpose is to characterize the nature, size, and distribution of stringer particles which result from the powder metallurgy (P/M) processing of these alloys. Microstructural features associated with the stringer particles are reported that help explain the stress corrosion susceptibility of the powder metallurgy-processed Al-Li-Cu alloys. In addition, matrix precipitation events are documented for a variety of heat treatments and process variations. Hot rolling is observed to significant alter the nature of matrix precipitation, and the observations are correlated with concomitant mechanical property variations

Mechanisms of induction of regulatory B cells in the tumour microenvironment and their contribution to immunosuppression and pro-tumour responses

The presence of tumour-infiltrating immune cells was originally associated with the induction of anti-tumour responses and good a prognosis. A more refined characterization of the tumour microenvironment has challenged this original idea and evidence now exists pointing to a critical role for immune cells in the modulation of anti-tumour responses and the induction of a tolerant pro-tumour environment. The coordinated action of diverse immunosuppressive populations, both innate and adaptive, shapes a variety of pro-tumour responses leading to tumour progression and metastasis. Regulatory B cells have emerged as critical modulators and suppressors of anti-tumour responses. As reported in autoimmunity and infection studies, Bregs are a heterogeneous population with diverse phenotypes and different mechanisms of action. Here we review recent studies on Bregs from animal models and patients, covering a variety of types of cancer. We describe the heterogeneity of Bregs, the cellular interactions they make with other immune cells and the tumour itself, and their mechanism of suppression that enables tumour escape. We also discuss the potential therapeutic tools that may inhibit Bregs function and promote anti-tumour responses

Proyecto creación de una empresa de organización de fiestas infantiles en la ciudad de Machala de la provincia de “El Oro”, 2010

The game is the most pleasant activity with which counts the human being, since he is born until he has reason use, the game has been and it is the axis that moves its expectations to look for a while of rest and enjoy. The games propitiate the activation of cognitive and motive mechanisms, by means of situations of exploration of the own corporal possibilities and of resolution of motive problems, it is in this stage to contribute to the majority acquisition of patron basic motors with those that new movement options can be built and to develop the motive capacities and the basic abilities correctly. For this context is important to emphasize that the study resides in the implementation of a company that offers a service of infantile parties organization, with good facilities and overalls originals for the children's entertainment that contribute to its development and personal and emotional growth amusement

Proyecto creación de una empresa de organización de fiestas infantiles en la ciudad de Machala de la provincia de “El Oro”, 2010

The game is the most pleasant activity with which counts the human being, since he is born until he has reason use, the game has been and it is the axis that moves its expectations to look for a while of rest and enjoy. The games propitiate the activation of cognitive and motive mechanisms, by means of situations of exploration of the own corporal possibilities and of resolution of motive problems, it is in this stage to contribute to the majority acquisition of patron basic motors with those that new movement options can be built and to develop the motive capacities and the basic abilities correctly. For this context is important to emphasize that the study resides in the implementation of a company that offers a service of infantile parties organization, with good facilities and overalls originals for the children's entertainment that contribute to its development and personal and emotional growth amusement

Stabilization of Physical Systems via Saturated Controllers With Partial State Measurements

This article provides a constructive passivity-based control (PBC) approach to solve the set-point regulation problem for input-affine continuous nonlinear systems while considering bounded inputs. As customary in PBC, the methodology consists of two steps: energy shaping and damping injection. In terms of applicability, the proposed controllers have two advantages concerning other PBC techniques: 1) the energy shaping is carried out without solving partial differential equations and 2) the damping injection is performed without measuring the passive output. As a result, the proposed methodology is suitable to control a broad range of physical systems, e.g., mechanical, electrical, and electromechanical systems, with saturated control signals. We illustrate the applicability of the technique by designing controllers for systems in different physical domains, where we validate the analytical results via simulations and experiments

Tuning of Passivity-Based Controllers for Mechanical Systems

This article describes several approaches for tuning the parameters of a class of passivity-based controllers for standard nonlinear mechanical systems. In particular, we are interested in tuning controllers that preserve the mechanical system structure in the closed loop. To this end, first, we provide tuning rules for stabilization, i.e., the rate of convergence (exponential stability) and stability margin (input-to-state stability). Then, we provide guidelines to remove the overshoot. In addition, we propose a methodology to tune the gyroscopic-related parameters. We also provide remarks on the damping phenomenon to facilitate the practical implementation of our approaches. We conclude this article with experimental results obtained from applying our tuning rules to a fully actuated and an underactuated mechanical system

Systems and Methods for Noise Mitigation for Hybrid and Electric Aircraft

A system and method of noise mitigation for hybrid and electric aircraft, the aircraft having a controllable pitch propeller or rotor(s) with a plurality of blades. The propeller or rotor(s) are driven by a drive system to provide thrust for the aircraft, and the blades of the propeller or rotor(s) are further movable about pivot axis to vary a pitch thereof. A controller on-board the aircraft is operable to cause rotation or movement of the blades of the propeller or rotor(s) about their pivot axis to alter and/or focus at least one aspect of the propeller generated noise to reduce or mitigate such noise while maintaining a substantially constant thrust, altitude, and/or air speed of the aircraft

Systems and Methods for Noise Mitigation for Hybrid and Electric Aircraft

A system and method of noise mitigation for hybrid and electric aircraft, the aircraft having a controllable pitch propeller or rotor(s) with a plurality of blades. The propeller or rotor(s) are driven by a drive system to provide thrust for the aircraft, and the blades of the propeller or rotor(s) are further movable about pivot axis to vary a pitch thereof. A controller on-board the aircraft is operable to cause rotation or movement of the blades of the propeller or rotor(s) about their pivot axis to alter and/or focus at least one aspect of the propeller generated noise to reduce or mitigate such noise while maintaining a substantially constant thrust, altitude, and/or air speed of the aircraft