1,850 research outputs found
Teleonomic Entropy: Measuring the Phase-Space of End-Directed Systems
We introduce a novel way of measuring the entropy of a set of values undergoing changes. Such a measure becomes useful when analyzing the temporal development of an algorithm designed to numerically update a collection of values such as artificial neural network weights undergoing adjustments during learning. We measure the entropy as a function of the phase-space of the values, i.e. their magnitude and velocity of change, using a method based on the abstract measure of entropy introduced by the philosopher Rudolf Carnap. By constructing a time-dynamic two-dimensional Voronoi diagram using Voronoi cell generators with coordinates of value- and value-velocity (change of magnitude), the entropy becomes a function of the cell areas. We term this measure teleonomic entropy since it can be used to describe changes in any end-directed (teleonomic) system. The usefulness of the method is llustrated when comparing the different approaches of two search algorithms, a learning artificial neural network and a population of discovering agents
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Thesis Statement
My art is concerned with formalist issues, demonstrating as it does perceptual relationships and contradictions within a context of color, repeating shape, grid-like structure, and the alternate reinforcement of flat surface versus depiction of illusionistic space.</p
A Positive Project Outcome: Lessons from a Non-Dominant Government University-Based Program
This article explores factors contributing to a non-dominant collaboration paradigm in a partnership between a government-based international development agency and a university-based non-governmental organization. Anchored in Wood’s and Gray’s collaborative framework, this article describes how the steeply hierarchical partnership navigated the elements of collaboration – organizational autonomy; shared problem domain; interactive processes; shared rules, norms, and structures; and decision making – to produce non-dominant values and practices deriving from negotiated processes, rules, norms, and structures that produced positive collaboration outcomes. In particular, a history of prior mutually beneficial interactions emerges as a critical precondition for achieving a non-dominant collaboration in this case study’s steeply hierarchical organizational relationship, one in which egalitarianism and equal decision-making regarding the agenda and the goals of the collaboration could have been highly constrained
An assessment of learning gains from educational animated videos versus traditional extension presentations among farmers in Benin*
Article purchasedThis study compared the efficacy of linguistically and dialectically localized animated educational videos (LAV) against traditional learning extension (TLE) presentations for learning gains of knowledge around agricultural- and healthcare-related topics within a rural population in Benin. While both approaches demonstrated learning gains, LAV resulted in significantly higher test scores and more detailed knowledge retention. A key contribution of this research, moreover, involves the use of mobile phone technologies to further disseminate educational information. That is, a majority of participants expressed both a preference for the LAV teaching approach and a heightened interest in digitally sharing the information from the educational animations with others. Because the animations are, by design, readily accessible to mobile phones via Africa’s explosively expanding digital infrastructure, this heightened interest in sharing the animated videos also transforms each study participant into a potential a learning node and point of dissemination for the educational video’s material as well
A Study of Air Temperatures within Croupettes
An experimental study was conducted to find the variations in air temperature which occur within Croupettes during treatment of infants and small children with respiratory infections, and to discover some of the factors which influence change of air temperature. Fifty children, two months to three years of age, all of whom suffered respiratory illness and all of whom received Croupette therapy were included in the study. Data were collected over a test period of two hours and fifteen minutes for each child. The parallel group technique was used in analysis of data. Conclusions drawn were not conclusive because they were based upon limited data but the following trends were indicated: (1) other factors being equal, oxygen at seven liters and forced air at ten pounds pressure may be used interchangeably without altering the temperature of air within the Croupette, (2) other factors being equal, a direct relationship exists between the weight of the child and the temperature of air within the Croupette, (3) other factors being equal, a direct relationship exists between the body temperature of the child and the temperature of air within the Croupette, (4) other factors being equal, a direct relationship exists between the temperature of the room in which therapy is administered and the temperature of air within the Croupette. The hypothesis, that air temperatures within Croupettes may not be constant and may vary due to specific identifiable factors may be accepted. Because statistically significant variations in air temperature within Croupettes were found, it does not necessarily follow that the findings are medically significant. It is recommended that study be given to finding the optimum air temperature for the child suffering specific respiratory illness
Temperature Regulates Transcription in the Zebrafish Circadian Clock
It has been well-documented that temperature influences key aspects of the circadian clock. Temperature cycles entrain the clock, while the period length of the circadian cycle is adjusted so that it remains relatively constant over a wide range of temperatures (temperature compensation). In vertebrates, the molecular basis of these properties is poorly understood. Here, using the zebrafish as an ectothermic model, we demonstrate first that in the absence of light, exposure of embryos and primary cell lines to temperature cycles entrains circadian rhythms of clock gene expression. Temperature steps drive changes in the basal expression of certain clock genes in a gene-specific manner, a mechanism potentially contributing to entrainment. In the case of the per4 gene, while E-box promoter elements mediate circadian clock regulation, they do not direct the temperature-driven changes in transcription. Second, by studying E-box-regulated transcription as a reporter of the core clock mechanism, we reveal that the zebrafish clock is temperature-compensated. In addition, temperature strongly influences the amplitude of circadian transcriptional rhythms during and following entrainment by light–dark cycles, a property that could confer temperature compensation. Finally, we show temperature-dependent changes in the expression levels, phosphorylation, and function of the clock protein, CLK. This suggests a mechanism that could account for changes in the amplitude of the E-box-directed rhythm. Together, our results imply that several key transcriptional regulatory elements at the core of the zebrafish clock respond to temperature
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