This paper proposes the use of a novel control method based on interconnection and damping assignment-passivity-based control (IDA-PBC) in order to address the aerial physical interaction (APhI) problem for a quadroto...
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This paper proposes the use of a novel control method based on interconnection and damping assignment-passivity-based control (IDA-PBC) in order to address the aerial physical interaction (APhI) problem for a quadrotor unmanned aerial vehicle (UAV). The apparent physical properties of the quadrotor are reshaped in order to achieve better APhI performances, while ensuring the stability of the interaction through passivity preservation. The robustness of the IDA-PBC method with respect to sensor noise is also analyzed. The direct measurement of the external wrench, needed to implement the control method, is compared with the use of a nonlinear Lyapunov-based wrench observer and advantages/disadvantages of both methods are discussed. The validity and practicability of the proposed APhI method is evaluated through experiments, where for the first time in the literature, a lightweight all-in-one low-cost force/torque (f/T) sensor is used onboard of a quadrotor. Two main scenarios are shown: a quadrotor responding to external disturbances while hovering (physical human-quadrotor interaction), and the same quadrotor sliding with a rigid tool along an uneven ceiling surface (inspection/painting-like task).
As a major active component extracted from traditional Chinese herb Tripterygium wilfordii Hook f, triptolide exhibits multiple pharmacological effects. Autophagy is an evolutionary conserved intracellular catabolic p...
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As a major active component extracted from traditional Chinese herb Tripterygium wilfordii Hook f, triptolide exhibits multiple pharmacological effects. Autophagy is an evolutionary conserved intracellular catabolic process involved in cytoplasmic materials degradation. Autophagic dysfunction contributes to the pathologies of many human diseases, which makes it a promising therapeutic target. Recent studies have shown that triptolide exerts neuroprotection, anti-tumor activities, organ toxicity, and podocyte protection by modulating autophagy. This article highlights the current information on triptolide-modulated autophagy, analyzes the possible pathways involved, and describes the crosstalk between autophagy and apoptosis modulated by triptolide, in hope of providing implications for the roles of autophagy in pharmacological effects of triptolide and expanding its novel usage as an autophagy modulator.
f-18 sodium fluoride is a bone-seeking agent for the scintigrafic imaging of bone metabolism. It was approved for clinical use by the US food- and Drug-Administration (fDA) in 1972. The development of Tc-99m-based rad...
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f-18 sodium fluoride is a bone-seeking agent for the scintigrafic imaging of bone metabolism. It was approved for clinical use by the US food- and Drug-Administration (fDA) in 1972. The development of Tc-99m-based radiotracers for bone scintigrafy and their wide availability forced PET imaging with sodium fluoride to the background. However the global molybdenum shortage emerged to a huge problem for the conventional bone scintigrafy a few years ago and, as the problem has not been solved, we will be probably facing it again in the next years. furthermore, the development of modern hybrid scanners (PET/CT, PET/MR) allows a higher diagnostic accuracy with sodium fluoride than the conventional bone scintigrafy and that is the reason for the rising interest for this tracer. In this article we will be focusing on indications, protocols, interpretation and reporting of sodium fluoride PET and perform a comparison between PET imaging and conventional bone scanning.
Analytic philosophy is often associated with a physicalistic naturalism that privileges natural-scientific modes of explanation. Nevertheless there has since the 1980s been a heterodox, somewhat subterranean trend wit...
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Analytic philosophy is often associated with a physicalistic naturalism that privileges natural-scientific modes of explanation. Nevertheless there has since the 1980s been a heterodox, somewhat subterranean trend within analytic philosophy that seeks to articulate a more expansive, non-reductive conception of nature. This trend can be traced back to P.f. Strawson's 1985 book Skepticism and Naturalism: Some Varieties. However, Strawson has long been ignored in the literature around soft naturalism' - especially in comparison to John McDowell. One of the reasons for this is that Strawson's account of soft naturalism is not often viewed as particularly plausible - it has come in for heavy criticism from the likes of Sebastian Gardner (2007) and Robert Stern (2003). In this paper, I argue that Strawson's soft naturalism ought to be re-assessed: that his critics can be refuted, and that his naturalism remains a compelling alternative to the likes of McDowell's. I attempt this through a radicalisation' of the modest Strawson's position, demonstrating that his naturalism has implicit in it something like Marx's conception of human species-being'.
This essay introduces texts written in the 1950s and 1960s that left behind conceptual traces of the pressing questions that were raised for various authors from their experiences of exile under colonialism in Hong Ko...
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This essay introduces texts written in the 1950s and 1960s that left behind conceptual traces of the pressing questions that were raised for various authors from their experiences of exile under colonialism in Hong Kong. The primary focus was a comprehensive investigation into China's recent history and the working out of broader theoretical frameworks inspired by contemporary thinkers (mostly from Europe and the United States). The critical appropriation of liberal values became an important starting point in the theoretical writings of Lao Sze-kwang (??? 1927-2012). Intertwining the historical contexts of migration, exile, and Cold War colonialism with the development of Lao's thought will reveal his explicit concern with establishing open value systems. Exile in the form of a specific colonial liberal environment provided him with a space where he could reappropriate and communicate ideas related to the Confucian tradition, as well as critically comment on the contemporary liberalism off. A. Hayek (1899-1992).
The article draws attention to the forgotten ancestry of the four steps of comparison model (description - interpretation - juxtaposition - comparison). Comparativists largely attribute this to George *** [1964. Compa...
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The article draws attention to the forgotten ancestry of the four steps of comparison model (description - interpretation - juxtaposition - comparison). Comparativists largely attribute this to George *** [1964. Comparative Method in Education. NewYork: Holt, Rinehart and Winston], but among German scholars, it is mostly attributed to franz Hilker [1962. Vergleichende Padagogik. Munchen: Max Hueber]. Who, then, is the rightful author of the model? This article attempts to answer this question. The methodological approaches of the two authors will be compared and contextualised in respect to their academic lives, especially through the 1950s and 1960s. Hilker and Bereday both referred to each other's publications on several occasions, which indicates a close communication between them. In contrast to the Anglophone dominance of scientific journals today, their way of practising comparative education was multilingual. Their cooperation with the nascent national academic associations of those times is also examined. finally, the epistemological characteristics of the four steps model, including its limitations, and value for the field of comparative education today, are evaluated.
Most societies throughout history have instituted ways of dealing with criminals, including the penalty of death. How such a penalty is carried out or wherever it ought to be carried out at all is an ongoing discourse...
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Most societies throughout history have instituted ways of dealing with criminals, including the penalty of death. How such a penalty is carried out or wherever it ought to be carried out at all is an ongoing discourse. My research provides an understanding of how cultural practices, such as capital punishments, emerge from a people’s worldview by focusing on one particular indigenous African execution practice called Toko Atolia. Toko atolia, now defunct, was practiced by an ethnolinguistic community in pre-mid nineteenth century Ghana – West Africa – known as the Anlo-Ewes. Toko atolia took the form of burying recalcitrant miscreants alive in a ritualized manner. Toko atolia has been judged barbaric by modern externally imposed notions of justice and punishment. I offer an appreciation of the worldview that shaped toko atolia, and argue, contrarily, that this seemingly barbaric practice makes sense within the worldview of the pre-mid nineteenth century Anlo-Ewes. My ethnographic fieldwork and archival research provide a wealth of perspectives from which I have developed an analysis of the relationship people today have with toko atolia. My research seeks to advance intercultural understanding by showing how externally imposed judgments overlook deeper meanings in cultural practices. (for example, how does America deal with external perceptions of its justice system, especially with regard to the now practice of lethal injection behind closed doors?)
Based on the analysis of primary sources, the study documents the genesis of teacher education in Trnava, from the establishment of the teacher training in 1857 until 1950, when the teacher training institutes were ab...
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Based on the analysis of primary sources, the study documents the genesis of teacher education in Trnava, from the establishment of the teacher training in 1857 until 1950, when the teacher training institutes were abolished. It focuses on research into music education and music practice in teacher training institutes. At the same time, it profiles music teachers in these teacher training institutions and their influence on the quality of music education.
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