76 research outputs found
Building models of real-time systems from application software
We present a methodology for building timed models of real-time systems by adding time constraints to their application software. The applied constraints take into account execution times of atomic statements, the behavior of the system's external environment, and scheduling policies. The timed models of the application obtained in this manner can be analyzed by using time analysis techniques to check relevant real-time properties. We show an instance of the methodology developed in the TAXYS project for the modeling and analysis of real-time systems programmed in the Esterel language. This language has been extended to describe, by using pragmas, time constraints characterizing the execution platform and the external environment. An analyzable timed model of the real-time system is produced by composing instrumented C-code generated by the compiler. The latter has been re-engineered in order to take into account the pragmas. Finally, we report on applications of TAXYS to several nontrivial examples. © 2003 IEEE
Immune Aspects and Myometrial Actions of Progesterone and CRH in Labor
Progesterone and corticotropin-releasing hormone (CRH) have a critical role in pregnancy and labor, as changes related to these hormones are crucial for the transition from myometrial quiescence to contractility. The mechanisms related to their effect differ between humans and other species, thus, despite extensive research, many questions remain to be answered regarding their mediation in human labor. Immune responses to progesterone and CRH are important for labor. Progesterone acts as an immunomodulator which controls many immune actions during pregnancy, and its withdrawal releases the inhibitory action on inflammatory pathways. In humans, a “functional” progesterone withdrawal occurs with onset of labor through changes in progesterone metabolism, progesterone receptors, and other molecules that either facilitate or antagonize progesterone function. Placental CRH acts on the fetal pituitary-adrenal axis to stimulate adrenal production of androgens and cortisol and also acts directly on myometrial cells via its receptors. CRH also affects inflammatory signals and vice versa. Interactions between progesterone and CRH additionally occur during labor. We describe the role of these two hormones in human myometrium and their interactions with the immune system during labor
Performative Framework and Case Study for Technology-Enhanced Learning Communities
This paper employs the overarching concept of communities to express the social contexts within which human creativity is exercised and learning happens. With the advent of digital technologies, these social contexts, the communities we engage in, change radically. The new landscape brought about by digital technologies is characterized by new qualities, new opportunities for action, new community affordances. The term onlife is adopted from the Onlife Manifesto and used to distinguish the new kind of communities brought about by the modern digital technologies, the onlife communities. Design principles are presented to foster such communities and support their members. These principles constitute a framework that emphasizes the concept of performativity, i.e. knowledge is based on human performance and actions done within certain social contexts, rather than development of conceptual representations. To demonstrate the use of the framework and the corresponding principles, the paper presents how they can be used to analyze, evaluate and reframe a concrete system addressing creativity and learning in the field of cultural heritage (history teaching and learning). One of the most significant results is the adoption of principles that facilitate students’ engagement in rich learning experiences moving from the role of end-user towards the role of expert-user with the support of so called maieuta-designers. The result of this process is the use of the studied software not only to consume ready-made content but the creation of new, student generated content, offering new learning opportunities to the students. As the evaluation shows, these new learning opportunities enable students to develop a deeper understanding of the topics studied
Performative Framework and Case Study for Technology-Enhanced Learning Communities
This paper employs the overarching concept of communities to express the social contexts within which human creativity is exercised and learning happens. With the advent of digital technologies, these social contexts, the communities we engage in, change radically. The new landscape brought about by digital technologies is characterized by new qualities, new opportunities for action, new community affordances. The term onlife is adopted from the Onlife Manifesto and used to distinguish the new kind of communities brought about by the modern digital technologies, the onlife communities. Design principles are presented to foster such communities and support their members. These principles constitute a framework that emphasizes the concept of performativity, i.e. knowledge is based on human performance and actions done within certain social contexts, rather than development of conceptual representations. To demonstrate the use of the framework and the corresponding principles, the paper presents how they can be used to analyze, evaluate and reframe a concrete system addressing creativity and learning in the field of cultural heritage (history teaching and learning). One of the most significant results is the adoption of principles that facilitate students’ engagement in rich learning experiences moving from the role of end-user towards the role of expert-user with the support of so called maieuta-designers. The result of this process is the use of the studied software not only to consume ready-made content but the creation of new, student generated content, offering new learning opportunities to the students. As the evaluation shows, these new learning opportunities enable students to develop a deeper understanding of the topics studied.Bulgarian Ministry of Education and Science under the National Research Programme "Cultural heritage, national memory and development of society" and the National
Scientific Program “Information and Communication Technologies for a Single
Digital Market in Science, Education and Security” approved by DCM №577/17.08.2018;
EVANDE project (contract number ECHO/SUB/2014/693261); Erasmus+
projects DISCOVER (2017-1-BG01-KA202-036327), and MUSILIB (2018-1-FI01-KA201-047196)
Operational Conceptual Modeling in Building and Sustaining Technology Enhanced Learning Communities
This paper presents a systematic approach to building and sustaining technology-enhanced learning communities based on a conceptual model that enables the analysis and enhancement of digital platforms and tools that promote creativity and learning. Two such software systems are presented, and their usage is analyzed. Experimental results are also presented that demonstrate the effectiveness of the conceptual model in enhancing the learning experiences offered
Prenatal diagnosis of Wolf-Hirschhorn syndrome confirmed by comparative genomic hybridization array: report of two cases and review of the literature
Wolf-Hirschhorn syndrome (WHS) is a well known genetic condition caused by a partial deletion of the short arm of chromosome 4. The great variability in the extent of the 4p deletion and the possible contribution of additional genetic rearrangements lead to a wide spectrum of clinical manifestations. The majority of the reports of prenatally diagnosed WHS cases are associated with large 4p deletions identified by conventional chromosome analysis; however, the widespread clinical use of novel molecular techniques such as array comparative genomic hybridization (a-CGH) has increased the detection rate of submicroscopic chromosomal aberrations associated with WHS phenotype. We provide a report of two fetuses with WHS presenting with intrauterine growth restriction as an isolated finding or combined with oligohydramnios and abnormal Doppler waveform in umbilical artery and uterine arteries. Standard karyotyping demonstrated a deletion on chromosome 4 in both cases [del(4)(p15.33) and del(4)(p15.31), respectively] and further application of a-CGH confirmed the diagnosis and offered a precise characterization of the genetic defect. A detailed review of the currently available literature on the prenatal diagnostic approach of WHS in terms of fetal sonographic assessment and molecular cytogenetic investigation is also provided
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