Search results for "Axis"

Non-Conventional Tunable Spatial Filtering

1987

A virtual display of the Fraunhofer diffraction pattern of any object is formed in the transverse source plane by theyirtual diffracted rays extqn0ing in the region to the left of the screen containing the transparencyl),2). Except for a few cases '')"°), the concept of virtual Fourier transform appears not to have been made use of. The main idea of this paper is, bearing in mind the property referred to in the above paragraph, to describe a novel spatial filtering technique. In this way, one can obtain different filtered images, by simply moving the point source along the optical axis. The basic theory is described below.

Analytical prediction of ultimate moment and curvature of RC rectangular sections in compression

2013

This paper presents closed form expressions linking the ultimate bearing capacity to the ultimate curvature of rectangular RC sections subjected to axial load and bending moment acting in one of the two symmetry planes of the section. With respect to possible simplified formulations the following effects are also considered: confinement of the concrete, hardening of the longitudinal reinforcement, and presence of reinforcing bars distributed orthogonally to the neutral axis. The formulation is proposed in dimensional terms after a preliminary definition of the geometrical and mechanical parameters governing the structural response of the class of sections considered. The analytical expressi…

Neuroendocrine responses in neonatal mother-deprived rabbits.

2009

To study both short- and long-term adaptation mechanisms activated by rabbits which were separated from their mothers (DLS) for 48 h between postnatal days 9 and 11, we examined plasma corticosterone concentrations before, during, and after DLS as well as the expression of glucocorticoid receptor (GR) in the hippocampus and the adrenal axis responses to a mild stress stimuli or exogenous ACTH injection. At postnatal day 10, plasma corticosterone concentration of DLS rabbits was similar to that of controls, but rose two-fold at day 11 (17.7 + or - 1.3 vs. 9.3 + or - 1.2 microg/dl, P0.01) and then decreased at day 12, when suckling was allowed again, to match those of controls with no differe…

Prophylaxis of hemicrania continua: two new cases effectively treated with topiramate.

2007

Hemicrania continua (HC) is an uncommon and under-recognized primary headache disorder characterized by a strictly unilateral continuous headache of moderate intensity with possible exacerbations and associated with ipsilateral autonomic features. HC has generally a prompt and enduring response to indomethacin although 25% to 50% of treated patients develop gastrointestinal side effects. These cases pose a difficult management challenge as no other drug is consistently effective in HC. Recently 2 HC patients responsive to topiramate treatment have been reported. Here we describe 2 more patients effectively treated with topiramate. Neither reported any side effects and one had persisting res…

Venous thromboembolism prophylaxis in elderly patients admitted to Italian internal medicine wards

2013

Above-bandgap ordinary optical properties of GaSe single crystal

2009

We report above-bandgap ordinary optical properties of ε-phase GaSe single crystal. Reference-quality pseudodielectric function 〈ε(E)〉 = 〈ε1(E)〉+i〈ε2(E)〉 and pseudorefractive index 〈N(E)〉 = 〈n(E)〉+i〈k(E)〉 spectra were measured by spectroscopic ellipsometry from 0.73 to 6.45 eV at room temperature for the light polarization perpendicular to the optic axis (math⊥math). The 〈ε〉 spectrum exhibited several interband-transition critical-point structures. Analysis of second-energy derivatives calculated numerically from the measured data yielded the critical-point energy values. Carmen.Martinez-Tomas@uv.es

Early asymmetric cues triggering the dorsal/ventral gene regulatory network of the sea urchin embryo

2014

Dorsal/ventral (DV) patterning of the sea urchin embryo relies on a ventrally-localized organizer expressing Nodal, a pivotal regulator of the DV gene regulatory network. However, the inceptive mechanisms imposing the symmetry-breaking are incompletely understood. In Paracentrotus lividus, the Hbox12 homeodomain-containing repressor is expressed by prospective dorsal cells, spatially facing and preceding the onset of nodal transcription. We report that Hbox12 misexpression provokes DV abnormalities, attenuating nodal and nodal-dependent transcription. Reciprocally, impairing hbox12 function disrupts DV polarity by allowing ectopic expression of nodal. Clonal loss-of-function, inflicted by b…

The pleiotropic effects of antiplatelet therapies

2019

Percutaneous coronary intervention is the most often used method for coronary revascularization. Stenting restores blood perfusion to ischemic areas, but it also causes mechanical disruption of the atheromatous plaque and the nearby endothelium, stimulating the activation of platelets. In a similar way, platelets are activated by thrombin exposure in the setting of plaque rupture. The interaction between platelets, oxidative stress and inflammation is an important factor determining the extent and severity of vascular dysfunction observed in these settings. Platelets activated by the vessel trauma release inflammatory and mitogenic mediators into the vascular microenvironment, activating le…

Decision-making Tool for Moving from 3-axes to 5-axes CNC Machine-tool

2016

Abstract Nowadays most of the parts within machine-building industry are machines on CNC machine-tools. According to their mechanical and kinematic structure, CNC machine-tools can be divided into 3-axes and 5-axes ones. Each type has its advantages and drawbacks and choosing between them could be a very difficult process. This paper presents a decision support tool for aiding the process of selecting between using and/or buying either a 3-axes CNC milling machine or a 5-axes milling machine, based upon fuzzy logic. The tool was built using the Fuzzy Logic Toolbox and the fuzzy graphical user interface (GUI) within Matlab software package.

Nonlinear analysis of cylindrical and conical hysteretic whirl motions in rotor-dynamics

2014

Abstract The internal friction of a rotor–shaft-support system is mainly due to the shaft structural hysteresis and to some possible shrink-fit release of the assembly. The experimentation points out the destabilizing effect of the internal friction in the over-critical rotor running. Nevertheless, this detrimental influence may be efficiently counterbalanced by other external dissipative sources located in the supports or by a proper anisotropic configuration of the support stiffness. The present analysis considers a rotor–shaft system which is symmetric with respect to the mid-span and is constrained by viscous-flexible supports with different stiffness on two orthogonal planes. The cylin…