It is the traditional view of psychology that the attributes of sensation show a one-to-one correspondence to the dimensions of the stimulus. Some such view is also implicit in the naïve epistemology of the physicist. He often thinks of pitch as if it were the perception of the frequency of a tone, but that view soon runs into difficulties. Within psychology it was Wundt who originally equipped sensation with two attributes, quality and intensity, thus making sensations mirror the more obvious (...) aspects of stimuli which differ as to kind and in degree. Later it became clear to Külpe that extension must be an attribute of visual and tactual sensations because the retina and the skin are areal organs and because extent enters into perception quite as ‘immediately’ as does intensity. A loud sound is not a congeries of faint sounds, nor is a perceived line a row of sensations. In a similar reaction against Wundtian atomism Külpe also added duration to the list, for a tone that lasts 0.8 sec. yields a different perception from one that lasts 0.6 sec. and yet there is no sense to saying that the first represents a greater number of seried sensations than the second. Thus the four classical attributes of sensation are quality, intensity, extensity and protensity. The conventional view has been that they are respectively correlated with four aspects of the stimulus, and this paper is written with the intention of refuting this view. (shrink)

En este artículo se reconocen los aportes de la flosofía de las prácticas experimentales en torno al debate teoría – práctica y se destaca su infuencia en el papel del experimento en la enseñanza de las ciencias, particularmente en el uso por parte de los libros de texto, tomando como ejemplo un caso en electricidad.

Integrated pest management has emerged as an important means of managing agricultural pests. Since the mid-1980s, the emphasis in IPM has shifted toward biologically-intensive and participatory research and extension approaches. Finding better means for solving pest problems is high on the agenda for most farmers, and farmers often have significant pest management knowledge and interest in IPM experimentation. This paper describes an approach to participatory IPM research that is being implemented by the IPM Collaborative Research Support Program (IPM CSRP). The (...) approach emphasizes on-farm research with an extrapolation domain beyond the single farm, and in some cases beyond the local region or country. It considers many factors beyond the farm and research station that influence the generation and adoption of IPM technologies and strategies. It emphasizes linkages among farmers, scientists, consumers, bankers, marketers/processors, and policy makers in IPM research priority setting, conduct, and evaluation. The interdisciplinary approach described in the paper is illustrated with a case study from the Philippines. Lessons and conclusions draw on its recent application in other sites as well. (shrink)

When rates of transcription from specific genes change, delays of variable length intervene before the corresponding mRNAs and proteins attain new levels. For most mammalian genes, the time required to complete transcription, processing, and transport of mRNA is much shorter than the period needed to achieve a new, steady‐state level of protein. Studies of inducible genes have shown that the period required to attain new levels of individual mRNAs and proteins is related to their unique half‐lives. The basis for this (...) is a physical principle that predicts rates of accumulation of particles in compartmental systems. The minimum period required to achieve a new level is directly proportional to product half‐lives because rates of decay control the ratio between the rate of synthesis and the concentration of gene products at steady state. This kinetic model suggests that sensitivity of gene products to degradation by ribonucleases and proteinases is an important determinant of the time scale of gene expression. (shrink)

We show that the implicational fragment of intuitionism is the weakest logic with a non-trivial probabilistic semantics which satisfies the thesis that the probabilities of conditionals are conditional probabilities. We also show that several logics between intuitionism and classical logic also admit non-trivial probability functions which satisfy that thesis. On the other hand, we also prove that very weak assumptions concerning negation added to the core probability conditions with the restriction that probabilities of conditionals are conditional probabilities are sufficient to (...) trivialize the semantics. (shrink)

Virtue ethics, the authors believe, is distinct and superior to other options because it considers, in the first place, which preferences are worth pursuing, rather than just blindly maximizing preferences, and it takes into account intuitions, emotions and experience, instead of acting solely on abstract universal principles. Moreover, virtue ethics is seen as firmly rooted in human biology and psychology, particularly in our freedom, rationality, and sociability. Work, business, and management are presented as vital areas for the development of virtues, (...) not the least with a view to human flourishing. We conclude by introducing the articles included in this special issue. (shrink)

Virtue ethics, the authors believe, is distinct and superior to other options because it considers, in the first place, which preferences are worth pursuing, rather than just blindly maximizing preferences, and it takes into account intuitions, emotions and experience, instead of acting solely on abstract universal principles. Moreover, virtue ethics is seen as firmly rooted in human biology and psychology, particularly in our freedom, rationality, and sociability. Work, business, and management are presented as vital areas for the development of virtues, (...) not the least with a view to human flourishing. We conclude by introducing the articles included in this special issue. (shrink)