Oxidative Stress and Multi-Organel Damage Induced by Two Novel Phytocannabinoids,CBDB and CBDP,in Breast Cancer Cells

Over the last few years, much attention has been paid to phytocannabinoids derived from Cannabis for their therapeutic potential. Δ⁹-tetrahydrocannabinol (Δ⁹-THC) and cannabidiol (CBD) are the most abundant compounds of the Cannabis sativa L. plant. Recently, novel phytocannabinoids, such as cannabidibutol (CBDB) and cannabidiphorol (CBDP), have been discovered. These new molecules exhibit the same terpenophenolic core of CBD and differ only for the length of the alkyl side chain. Roles of CBD homologs in physiological and pathological processes are emerging but the exact molecular mechanisms remain to be fully elucidated. Here, we investigated the biological effects of the newly discovered CBDB or CBDP, compared to the well-known natural and synthetic CBD (nat CBD and syn CBD) in human breast carcinoma cells that express CB receptors. In detail, our data demonstrated that the treatment of cells with the novel phytocannabinoids affects cell viability, increases the production of reactive oxygen species (ROS) and activates cellular pathways related to ROS signaling, as already demonstrated for natural CBD. Moreover, we observed that the biological activity is significantly increased upon combining CBD homologs with drugs that inhibit the activity of enzymes involved in the metabolism of endocannabinoids, such as the monoacylglycerol lipase (MAGL) inhibitor, or with drugs that induces the activation of cellular stress pathways, such as the phorbol ester 12-myristate 13-acetate (PMA).     

Flow Rate Boundary Conditions in Fluid-Dynamics

The defective flow rate problem in fluid-dynamics has been solved in the engineering literature by precribing a proria velocity profile fitting the desired flow rate. Here, we describe an alternative formulation, relying on a constraint minimization problem. We prove some a prioriestimates and we show some numerical results. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)     

Studies on organo-mercury compounds speciation

Four studies on organo-mercury compounds speciation carried out in the analytical chemistry laboratory of the University of Santiago are briefly described and discussed. Search for new methods of separation based on liquid chromatography as well as quality control and application studies have been started and the results obtained up to the end of 1990 are presented.     

Externality and Hamilton-Jacobi equations

The relationship between optimal control problems and Hamilton-Jacobi-Bellman equations is well known [9]. In fact the value function, defined as the infimum of the cost functional, satisfies in the viscosity sense an appropriate Hamilton-Jacobi-Bellman equation. In this paper we consider several control problems such that the cost functional associated to each problem depends explicitly on the value functions of the other problems. This leads to a system of Hamilton-Jacobi-Bellman equations. This is known, in economic context [14] cap XI, as an externality problem. In these problems may occur a lack of uniqueness of the value functions. We give conditions to ensure existence, uniqueness of the value functions and an implicit integral representation formula. Moreover, under uniqueness assumption, we prove that the variational solutions of the associated Hamilton-Jacobi system converge asymptotically to the value functions. We prove also an uniqueness theorem in the case of viscosity solutions of Hamilton-Jacobi-Bellman system.     

SAW characteristics of AlN films sputtered on silicon substrates

This article is focused on the analysis of the electroacoustic response of surface acoustic wave (SAW) filters made of aluminium nitride (AlN) thin films on various types of Si wafers. AlN films with (00.2) orientation were deposited by RF reactive sputtering of an Al target in Ar and N(2) admixtures on Si(100) and (111) wafers with resistivities ranging between 10 and 2000 Omega cm. The electroacoustic response of SAW filters with an acoustic wavelength of 40 microm was analysed by measuring the Sij parameters with a network analyser. We have determined that the out-of-band loss is directly related to the Si substrate resistivity, varying from 26 dB for 10 Omega cm to 55 dB for 2000 Omega cm. The SAW velocity depends on the orientation of the Si wafer, being approximately 4700 m/s for Si(111) and 5100 m/s for Si(100). The electroacoustic responses of the SAW filters were fitted by computations based on a simple circuital model that takes into account parasitic effects such as airborne electromagnetic coupling and conduction through the substrate. This procedure provides accurate values of the electromechanical coupling factor k2 even for devices with poor characteristics. Good quality SAW filters of AlN on high resistivity Si(100) wafers with k2 larger than 0.12% are demonstrated.     

Scattering of solitary waves from interfaces in granular media

The scattering of nonlinear solitary waves from an interface is numerically studied in detail. The interface is created by joining two one-dimensional chains of spherical beads of different radii (masses). Beads are assumed to be in Hertzian contact, without static precompression, and to have identical mechanical properties. In addition to previous findings, it is observed that in both cases, when a solitary wave travels from the light to the heavy system and vice versa, secondary multipulse structures are generated at the interface, being backscattered and forward scattered, respectively.     

Design of a pulse generator and shock tube for measuring hearing protector attenuation of high-amplitude impulsive noise

The effectiveness of hearing protectors against high amplitude impulse noise levels remains the subject of research with objective testing techniques using acoustic test fixtures offering the only realistic method of providing rapid performance data for protector design and qualification. The work presented in this paper examines a prototype test method based on a shock tube and acoustic test fixture for the evaluation of protectors against high-level impulsive noise where established real ear attenuation at threshold methods would be impractical to apply. The results show that the system is capable of producing controlled repeatable high amplitude pressure pulses of variable duration for testing hearing protection devices in a grazing wave type test. A series of pilot tests illustrate how the system can have a sufficient self-insertion loss to reject flanking noise and allow the measurement of protector attenuations of up to 45 dB with little corruption from flanking noise.     

On the Geometry of Orthomodular Spaces over Fields of Power Series

Orthomodular spaces are generalizations ofHilbert spaces with which they share the basic propertyexpressed by the Projection Theorem. We study twoinfinite-dimensional orthomodular spaces, bothconstructed over the same field of power series, but withdifferent inner products. On the first space everybounded, self-adjoint operator decomposes into anorthogonal sum of operators of rank 1 or 2; on thesecond space, in contrast, there exist self-adjointoperators that are undecomposable. These differencesreflect the fact that the underlying geometries aredissimiliar.