Vertical cultural transmission effects on demic front propagation: Theory and application to the Neolithic transition in Europe

It is shown that Lotka-Volterra interaction terms are not appropriate to describe vertical cultural transmission. Appropriate interaction terms are derived and used to compute the effect of vertical cultural transmission on demic front propagation. They are also applied to a specific example, the Neolithic transition in Europe. In this example, it is found that the effect of vertical cultural transmission can be important (about 30%). On the other hand, simple models based on differential equations can lead to large errors (above 50%). Further physical, biophysical, and cross-disciplinary applications are outlined

Entrevista con Manuel Villegas sobre 'El error de Prometeo. Psico(pato)logía del desarrollo moral'

Entrevista con Manuel Villegas

La educación moral en la enseñanza obligatoria

Quien lea este libro, desde la introducción a las notas o quien conozca la trayectoria y ciertas publicaciones anteriores de su autor, sabrá que esta recensión ha sido escrita desde un lugar en el que la neutralidad y la imparcialidad resultan del todo improbables. La obra de Josep M.ª Puig objeto de la presente reseña tiene como referencia y marco de reflexión fundamentales los trabajos previos del GREM (Grup de Recerca en Educació Moral de la Universitat de Barcelona), equipo del que también forma parte el autor de esta reseña. Resulta asimismo que el autor de estas líneas hace más de veinte años que es amigo y colega del autor del libro. Y que, por si fuera poco, el autor del libro reconoce en su introducción una supuesta 'deuda especial' con el autor de la reseña. Con tales antecedentes, la credibilidad de esta recensión ha de quedar irremediablemente bajo mínimos. Por esta razón, voy a limitarme a señalar los defectos principales que a mi modo de ver tiene la obra.

On the Application of Beam on Elastic Foundation Theory to the Analysis of Stiffened Plate Strips

The main objective of this thesis is to show that plate strips subjected to transverse line loads can be analysed by using the beam on elastic foundation (BEF) approach. It is shown that the elastic behaviour of both the centre line section of a semi infinite plate supported along two edges, and the free edge of a cantilever plate strip can be accurately predicted by calculations based on the two parameter BEF theory. The transverse bending stiffness of the plate strip forms the foundation. The foundation modulus is shown, mathematically and physically, to be the zero order term of the fourth order differential equation governing the behaviour of BEF, whereas the torsion rigidity of the plate acts like pre tension in the second order term. Direct equivalence is obtained for harmonic line loading by comparing the differential equations of Levy's method (a simply supported plate) with the BEF method. By equating the second and zero order terms of the semi infinite BEF model for each harmonic component, two parameters are obtained for a simply supported plate of width B: the characteristic length, 1/ λ, and the normalized sum, n, being the effect of axial loading and stiffening resulting from the torsion stiffness, nlin. This procedure gives the following result for the first mode when a uniaxial stress field was assumed (ν = 0): 1/λ = √2B/π and nlin = 1. For constant line loading, which is the superimposition of harmonic components, slightly differing foundation parameters are obtained when the maximum deflection and bending moment values of the theoretical plate, with v = 0, and BEF analysis solutions are equated: 1 /λ= 1.47B/π and nlin. = 0.59 for a simply supported plate; and 1/λ = 0.99B/π and nlin = 0.25 for a fixed plate. The BEF parameters of the plate strip with a free edge are determined based solely on finite element analysis (FEA) results: 1/λ = 1.29B/π and nlin. = 0.65, where B is the double width of the cantilever plate strip. The stress biaxial, v > 0, is shown not to affect the values of the BEF parameters significantly the result of the geometric nonlinearity caused by in plane, axial and biaxial loading is studied theoretically by comparing the differential equations of Levy's method with the BEF approach. The BEF model is generalised to take into account the elastic rotation stiffness of the longitudinal edges. Finally, formulae are presented that take into account the effect of Poisson's ratio, and geometric non linearity, on bending behaviour resulting from axial and transverse inplane loading. It is also shown that the BEF parameters of the semi infinite model are valid for linear elastic analysis of a plate strip of finite length. The BEF model was verified by applying it to the analysis of bending stresses caused by misalignments in a laboratory test panel. In summary, it can be concluded that the advantages of the BEF theory are that it is a simple tool, and that it is accurate enough for specific stress analysis of semi infinite and finite plate bending problems.

Ètica per aixecar la Moral : Problemes ètics als serveis socials bàsics en temps de crisi

Els riscos ètics als serveis socials en temps de crisi es multipliquen i s’intensifiquen, però en essència no es tracta de riscos nous ni diferents dels que es podien produir en temps de bonança econòmica i social. No obstant, la cruesa del context dels serveis socials bàsics (freqüència de les situacions límit que s'han d'atendre, les qüestions internes i externes de la pràctica professional, el malestar i desencant dels professionals) pot suposar una oportunitat de visibilitat i prendre consciència d'aquests riscos ètics. A la vegada, l'anàlisi i l'abordatge d'aquest nou context des d'una perspectiva ètica pot suposar un antídot que permeti ressituar la pràctica professional (amb els seus límits, però també amb les seves possibilitats), millorar-ne la qualitat i la transparència, i, de retruc, trencar amb la dinàmica de cronificació de la insatisfacció i queixa professional. És a dir, la perspectiva ètica pot ajudar a aixecar la moral dels professionals. Així doncs, amb aquesta recerca pretenem assolir els següents objectius: Identificar els riscos ètics de la intervenció als serveis socials bàsics en relació als efectes i l'impacte de la crisi econòmica; analitzar els diferents riscos ètics identificats i efectuar propostes d'abordatge i minimització d'aquests riscos ètics

Retrieval of kinetic rates in reactions with semi batch liquid phase using ill-posed inverse problem theory

A neural network procedure to solve inverse chemical kinetic problems is discussed in this work. Rate constants are calculated from the product concentration of an irreversible consecutive reaction: the hydrogenation of Citral molecule, a process with industrial interest. Simulated and experimental data are considered. Errors in the simulated data, up to 7% in the concentrations, were assumed to investigate the robustness of the inverse procedure. Also, the proposed method is compared with two common methods in nonlinear analysis; the Simplex and Levenberg-Marquardt approaches. In all situations investigated, the neural network approach was numerically stable and robust with respect to deviations in the initial conditions or experimental noises.

A brief introduction to molecular orbital theory of simple polyatomic molecules for undergraduate chemistry students

A simple, four-step method for better introducing undergraduate students to the fundamentals of molecular orbital (MO) theory of the polyatomic molecules H2O, NH3, BH3 and SiH4 using group theory is reported. These molecules serve to illustrate the concept of ligand group orbitals (LGOs) and subsequent construction of MO energy diagrams on the basis of molecular symmetry requirements.

Evaluation of group electronegativities and hardness (softness) of group 14 elements and containing functional groups through density functional theory and correlation with NMR spectra data

Quantum Chemical calculations for group 14 elements of Periodic Table (C, Si, Ge, Sn, Pb) and their functional groups have been carried out using Density Functional Theory (DFT) based reactivity descriptors such as group electronegativities, hardness and softness. DFT calculations were performed for a large series of tetracoordinated Sn compounds of the CH3SnRR'X type, where X is a halogen and R and R' are alkyl, halogenated alkyl, alkoxy, or alkyl thio groups. The results were interpreted in terms of calculated electronegativity and hardness of the SnRR'X groups, applying a methodology previously developed by Geerlings and coworkers (J. Phys. Chem. 1993, 97, 1826). These calculations allowed to see the regularities concerning the influence of the nature of organic groups RR' and inorganic group X on electronegativities and hardness of the SnRR'X groups; in this case, it was found a very good correlation between the electronegativity of the fragment and experimental 119Sn chemical shifts, a property that sensitively reflects the change in the valence electronic structure of molecules. This work was complemented with the study of some compounds of the EX and ER types, where E= C, Si, Ge, Sn and R= CH3, H, which was performed to study the influence that the central atom has on the electronegativity and hardness of molecules, or whether these properties are mainly affected for the type of ligand bound to the central atom. All these calculations were performed using the B3PW91 functional together with the 6-311++G** basis set level for H, C, Si, Ge, F, Cl and Br atoms and the 3-21G for Sn and I atoms.

Leibniz's theory of bodies: monadic aggregates, phenomena, or both?

Leibniz's conception of bodies seems to be a puzzling theory. Bodies are seen as aggregates of monads and as wellfounded phenomena. This has initiated controversy and unending discussions. The paper attempts to resolve the apparent inconsistencies by a new and formally spirited reconstruction of Leibniz's theory of monads and perception, on the one hand, and a (re-)formulation and precisation of his concept of preestablished harmony, on the other hand. Preestablished harmony is modelled basically as a covariation between the monadic and the ideal realm.

Hume, liberty and the object of moral evaluation

Hume's project concerning the conflict between liberty and necessity is ";reconciliatory";. But what is the nature of Hume's project? Does he solve a problem in metaphysics only? And when Hume says that the dispute between the doctrines of liberty and necessity is merely verbal, does he mean that there is no genuine metaphysical dispute between the doctrines? In the present essay I argue for: (1) there is room for liberty in Hume's philosophy, and not only because the position is pro forma compatibilist, even though this has importance for the recognition that Hume's main concern when discussing the matter is with practice; (2) the position does not involve a ";subjectivization"; of every form of necessity: it is not compatibilist because it creates a space for the claim that the operations of the will are non-problematically necessary through a weakning of the notion of necessity as it applies to external objects; (3) Hume holds that the ordinary phenomena of mental causation do not preempt the atribuition of moral responsibility, which combines perfectly with his identification of the object of moral evaluation: the whole of the character of a person, in relation to which there is, nonetheless, liberty. I intend to support my assertions by a close reading of what Hume states in section 8 of the first Enquiry.