Theoretical and experimental research on parameter tracking systems Final report, 15 Jul. 1964 - Aug. 1965

Parameter tracking systems based on equation error approach for mathematical model of unknown plan

On the total curvatures of a tame function

Given a definable function f, enough differentiable, we study the continuity of the total curvature function t --> K(t), total curvature of the level {f=t}, and the total absolute curvature function t-->|K| (t), total absolute curvature of the level {f=t}. We show they admits at most finitely many discontinuities

Trace Metals Bioaccumulation Potentials of Three Indigenous Grasses Grown on Polluted Soils Collected Around Mining Areas in Pretoria, South Africa

The rapid increase in the number of industries may have increased the levels of trace metals in the soil. Phytoremediation of these polluted soils using indigenous grasses is now considered an alternative method in remediating these polluted soils. The present study investigated and compared the ability of three indigenous grasses as bioaccumulators of trace metals from polluted soils. Seeds of these grasses were introduced into pots containing polluted soil samples after the addition of organic manure. The seeds of the grasses were allowed to germinate and grow to maturity before harvesting. The harvested grasses were later separated into shoots and roots and the trace metal contents were determined using ICP –MS. From all the grasses, the concentrations of trace metals in the roots were more than those recorded in the shoot with a significant difference (P < 0.05). The transfer factor (TF) showed that Zn was the most bioaccumulated trace metals by all the grasses followed by Pb, Mn, and Cu respectively. Chromium concentration from the shoot of the grasses was in the order Urochlora moasambicensis > Themeda trianda > Cynodon dactylon. The study concluded that the three grasses used were all able to bioaccumulate trace metals in a similar proportion from the polluted soils. However, since livestock feed on these grasses, they should not be allowed to feed on the grasses used in this study especially when harvested from a polluted soil due to their bioaccumulative potentials

Redox Proteomics and Platelet Activation: Understanding the Redox Proteome to Improve Platelet Quality for Transfusion.

Blood banks use pathogen inactivation (PI) technologies to increase the safety of platelet concentrates (PCs). The characteristics of PI-treated PCs slightly differ from those of untreated PCs, but the underlying reasons are not well understood. One possible cause is the generation of oxidative stress during the PI process. This is of great interest since reactive oxygen species (ROS) act as second messengers in platelet functions. Furthermore, there are links between protein oxidation and phosphorylation, another mechanism that is critical for cell regulation. Current research efforts focus on understanding the underlying mechanisms and identifying new target proteins. Proteomics technologies represent powerful tools for investigating signaling pathways involving ROS and post-translational modifications such as phosphorylation, while quantitative techniques enable the comparison of the platelet resting state versus the stimulated state. In particular, redox cysteine is a key player in platelet activation upon stimulation by different agonists. This review highlights the experiments that have provided insights into the roles of ROS in platelet function and the implications for platelet transfusion, and potentially in diseases such as inflammation and platelet hyperactivity. The review also describes the implication of redox mechanism in platelet storage considerations

Non-classical Photon Statistics For Two-mode Optical Fields

The non-classical property of subpoissonian photon statistics is extended from one to two-mode electromagnetic fields, incorporating the physically motivated property of invariance under passive unitary transformations. Applications to squeezed coherent states, squeezed thermal states, and superposition of coherent states are given. Dependences of extent of non-classical behaviour on the independent squeezing parameters are graphically displayed.Comment: 15 pages, RevTex, 5 figures, available by sending email to [email protected]

The clinical and biological impact of new pathogen inactivation technologies on platelet concentrates.

Since 1990, several techniques have been developed to photochemically inactivate pathogens in platelet concentrates, potentially leading to safer transfusion therapy. The three most common methods are amotosalen/UVA (INTERCEPT Blood System), riboflavin/UVA-UVB (MIRASOL PRT), and UVC (Theraflex-UV). We review the biology of pathogen inactivation methods, present their efficacy in reducing pathogens, discuss their impact on the functional aspects of treated platelets, and review clinical studies showing the clinical efficiency of the pathogen inactivation methods and their possible toxicity

Symplectic quantization, inequivalent quantum theories, and Heisenberg's principle of uncertainty

We analyze the quantum dynamics of the non-relativistic two-dimensional isotropic harmonic oscillator in Heisenberg's picture. Such a system is taken as toy model to analyze some of the various quantum theories that can be built from the application of Dirac's quantization rule to the various symplectic structures recently reported for this classical system. It is pointed out that that these quantum theories are inequivalent in the sense that the mean values for the operators (observables) associated with the same physical classical observable do not agree with each other. The inequivalence does not arise from ambiguities in the ordering of operators but from the fact of having several symplectic structures defined with respect to the same set of coordinates. It is also shown that the uncertainty relations between the fundamental observables depend on the particular quantum theory chosen. It is important to emphasize that these (somehow paradoxical) results emerge from the combination of two paradigms: Dirac's quantization rule and the usual Copenhagen interpretation of quantum mechanics.Comment: 8 pages, LaTex file, no figures. Accepted for publication in Phys. Rev.

Technology as a means of teaching mathematical education: an experience with university inicial students

Este trabajo expone el diseño e implementación de una propuesta tecno-pedagógica, cuyo objetivo fue introducir a los ingresantes en el aprendizaje de la matemática superior, a través de un enfoque de resolución de problemas que habilitó sus capacidades de exploración, experimentación, argumentación y reflexión. Trabajamos desde una perspectiva constructivista de la enseñanza y el aprendizaje, sosteniendo que hacer matemática –en este nuevo siglo– se debe acercar al modo de trabajo del matemático, quien indaga, explora, ajusta hipótesis, se contesta lo que no sabe, y así avanza. La propuesta fue desarrollada desde una modalidad semipresencial, con la que buscamos reinterpretar los ritmos de la enseñanza y del aprendizaje a la luz de la influencia tecnológica y redimensionarlos para favorecer procesos críticos y colegiados de apropiación del conocimiento. El registro de las ideas con las que concebimos y construimos la propuesta, junto con lo percibido en el desarrollo de las prácticas pedagógicas, nos permitió una primera reconstrucción a posteriori, que constituyó un segundo plano de análisis, posibilitando nuevas construcciones conceptuales.This work exposes the design and implementation of a techno-pedagogical proposal, whose objective was to introduce the students to the learning of higher mathematics, through a problem-solving approach that enabled their exploration, experimentation, argumentation and reflection capabilities. We worked from a constructivist perspective of teaching and learning, arguing that doing mathematics –in this new century– must approach the mathematician's way of working, who investigates, explores, adjusts hypotheses, answers what he does not know, and thus progresses. The proposal was developed from a blended mode, with which we seek to reinterpret the rhythms of teaching and learning in the light of technological influence and resize them to favor critical and collective processes of appropriation of knowledge. The registration of the ideas with which we conceived and constructed the proposal, together with what was perceived in the development of pedagogical practices, allowed us to find an initial a posteriori reconstruction, which constituted a second plane of analysis, making possible new conceptual constructions.Facultad de Informátic

Technology as a means of teaching mathematical education: an experience with university inicial students

Este trabajo expone el diseño e implementación de una propuesta tecno-pedagógica, cuyo objetivo fue introducir a los ingresantes en el aprendizaje de la matemática superior, a través de un enfoque de resolución de problemas que habilitó sus capacidades de exploración, experimentación, argumentación y reflexión. Trabajamos desde una perspectiva constructivista de la enseñanza y el aprendizaje, sosteniendo que hacer matemática –en este nuevo siglo– se debe acercar al modo de trabajo del matemático, quien indaga, explora, ajusta hipótesis, se contesta lo que no sabe, y así avanza. La propuesta fue desarrollada desde una modalidad semipresencial, con la que buscamos reinterpretar los ritmos de la enseñanza y del aprendizaje a la luz de la influencia tecnológica y redimensionarlos para favorecer procesos críticos y colegiados de apropiación del conocimiento. El registro de las ideas con las que concebimos y construimos la propuesta, junto con lo percibido en el desarrollo de las prácticas pedagógicas, nos permitió una primera reconstrucción a posteriori, que constituyó un segundo plano de análisis, posibilitando nuevas construcciones conceptuales.This work exposes the design and implementation of a techno-pedagogical proposal, whose objective was to introduce the students to the learning of higher mathematics, through a problem-solving approach that enabled their exploration, experimentation, argumentation and reflection capabilities. We worked from a constructivist perspective of teaching and learning, arguing that doing mathematics –in this new century– must approach the mathematician's way of working, who investigates, explores, adjusts hypotheses, answers what he does not know, and thus progresses. The proposal was developed from a blended mode, with which we seek to reinterpret the rhythms of teaching and learning in the light of technological influence and resize them to favor critical and collective processes of appropriation of knowledge. The registration of the ideas with which we conceived and constructed the proposal, together with what was perceived in the development of pedagogical practices, allowed us to find an initial a posteriori reconstruction, which constituted a second plane of analysis, making possible new conceptual constructions.Facultad de Informátic