Design of an active helicopter control experiment at the Princeton Rotorcraft Dynamics Laboratory

In an effort to develop an active control technique for reducing helicopter vibrations stemming from the main rotor system, a helicopter model was designed and tested at the Princeton Rotorcraft Dynamics Laboratory (PRDL). A description of this facility, including its latest data acquisition upgrade, are given. The design procedures for the test model and its Froude scaled rotor system are also discussed. The approach for performing active control is based on the idea that rotor states can be identified by instrumenting the rotor blades. Using this knowledge, Individual Blade Control (IBC) or Higher Harmonic Control (HHC) pitch input commands may be used to impact on rotor dynamics in such a way as to reduce rotor vibrations. Discussed here is an instrumentation configuration utilizing miniature accelerometers to measure and estimate first and second out-of-plane bending mode positions and velocities. To verify this technique, the model was tested, and resulting data were used to estimate rotor states as well as flap and bending coefficients, procedures for which are discussed. Overall results show that a cost- and time-effective method for building a useful test model for future active control experiments was developed. With some fine-tuning or slight adjustments in sensor configuration, prospects for obtaining good state estimates look promising

Spectral observations at the CILBO observatory: calibration and data sets

Stars and planetary system

Opera and poison : a secret and enjoyable approach to teaching and learning chemistry

The storyline of operas, with historical or fictional characters, often include potions and poisons. This has prompted a study of the chemistry behind some operatic plots. The results were originally presented as a lecture given at the University of Minho in Portugal, within the context of the International Year of Chemistry. The same lecture was subsequently repeated at other universities as an invited lecture for science students and in public theaters for wider audiences. The lecture included a multimedia and interactive content that allowed the audience to listen to arias and to watch video clips with selected scenes extracted from operas. The present article, based on the lecture, demonstrates how chemistry and opera can be related and may also serve as a source of motivation and inspiration for chemistry teachers looking for alternative pedagogical approaches. Moreover, the lecture constitutes a vehicle that transports chemistry knowledge to wider audiences through examples of everyday molecules, with particular emphasis on natural products.The author is pleased to express his gratitude to Jorge Calado and Michael John Smith for useful discussions. The author also thanks the reviewers of the manuscript for their helpful comments and suggestions. Thanks are due to the Foundation for Science and Technology (FCT,Portugal), QREN and FEDER/EU for financial support through the research centers, CQ/UM PEst-C/QUI/UI0686/2011. Ciencia Viva, Portugal, is also acknowledged for financial support of the activities organized by the University of Minho during the International Year of Chemistry. The author also expresses his gratitude to Ana Paula Ferreira and Andre Cunha Leal from RTP Antena 2 who contributed immensely to the popularization of the lecture on which this paper is based on

Vascular risk factors in glaucoma: the results of a national survey

Background The role of vascular risk factors in glaucoma is still being debated. To assess the importance of vascular risk factors in patients with primary open-angle glaucoma (POAG), data from the medical history of 2,879 POAG patients and 973 age-matched controls were collected and analyzed. Methods Design: observational survey. Setting: 35 Italian academic centers. Study population: POAG patients and age-matched controls. In order to reduce bias consecutive patients were included. Observation procedures: data concerning vascular risk factors were collected for all patients with a detailed questionnaire. A complete ophthalmological examination with assessment of intraocular pressure (IOP), visual field, optic disc, and systemic blood pressure was performed. Main outcome measures: the ESH-ESC (European Society of Hypertension-European Society of Cardiology) guidelines were used to calculate the level of cardiovascular risk. Crude and adjusted estimates of the odds ratios (OR) were calculated for all cardiovascular risk factors in POAG and controls. Results The study included 2,879 POAG patients and 973 controls. POAG cases had a significantly higher systolic and diastolic blood pressure (p=0.001) and systolic perfusion pressure (p=0.02) as compared with controls. Also mean IOP was significantly higher in the POAG group (p=0.01), while diastolic perfusion pressure was not significantly different in the two groups. Myopia was more prevalent in the POAG group (23 vs 18%, p=0.005) as well as a positive family history for glaucoma (26 vs 12%, p= 0.004). POAG patients tended to have a higher cardiovascular risk than controls: 63% of glaucoma cases vs 55% of controls (OR: 1.38, p=0.005) had a “high” or “very high” cardiovascular risk. Conclusions The level of cardiovascular risk was significantly higher in glaucoma patients than in controls

Bowel management for the treatment of pediatric fecal incontinence

Fecal incontinence is a devastating underestimated problem, affecting a large number of individuals all over the world. Most of the available literature relates to the management of adults. The treatments proposed are not uniformly successful and have little application in the pediatric population. This paper presents the experience of 30 years, implementing a bowel management program, for the treatment of fecal incontinence in over 700 pediatric patients, with a success rate of 95%. The main characteristics of the program include the identification of the characteristics of the colon of each patient; finding the specific type of enema that will clean that colon and the radiological monitoring of the process

Self-Consciousness as a Construction All the Way Down

Contemporary mind and brain sciences provide theories and data that seem to confirm a hypothesis about human nature that we might formulate as follows. Human life is conditioned by a need that is no less important than elementary biological needs (such as survival and reproduction) or universal forms of social competition: the need to build and, indeed, defend a subjective identity whose solidity and clarity are the foundation of our intra- and inter-personal equilibrium and therefore of psychological well-being and mental health. In this article, distancing ourselves from a neo- Cartesian position still prevalent in the philosophy of mind and approaching instead the outcomes of contemporary cognitive sciences, we sketch the complex interweaving of the cognitive, emotional, and affective elements that are constitutive of subjective identity, with a focus on the role played in self-identity construction by Theory-of-Mind abilities. We will suggest that, at every stage of self-construction, individuals engage in processes of understanding others that have a largely innate basis. In this perspective, a mature self-awareness is somewhat secondary to the knowledge of others, an evolutionarily refined acquisition primarily serving as a defense mechanism

Il problema della coscienza sullo sfondo delle scienze della mente e del cervello

Nell’indagare la soggettività, le scienze della mente e del cervello hanno seguito la lezione anti-idealistica di Darwin, procedendo "dal basso verso l’alto", sforzandosi cioè di spiegare come le funzioni psicologiche complesse che sono alla base dell’autoconoscenza introspettiva dell’adulto, evolvono da funzioni più basilari. Il punto di approdo di questo rovesciamento metodologico è una critica della soggettività, che ci rivela che il mondo fenomenologico della coscienza non possiede un carattere primario e fondante rispetto al resto della vita psichica. È questo il tema del presente scritto