Examination of Icing Induced Loss of Control and Its Mitigations

Factors external to the aircraft are often a significant causal factor in loss of control (LOC) accidents. In today s aviation world, very few accidents stem from a single cause and typically have a number of causal factors that culminate in a LOC accident. Very often the "trigger" that initiates an accident sequence is an external environment factor. In a recent NASA statistical analysis of LOC accidents, aircraft icing was shown to be the most common external environmental LOC causal factor for scheduled operations. When investigating LOC accident or incidents aircraft icing causal factors can be categorized into groups of 1) in-flight encounter with super-cooled liquid water clouds, 2) take-off with ice contamination, or 3) in-flight encounter with high concentrations of ice crystals. As with other flight hazards, icing induced LOC accidents can be prevented through avoidance, detection, and recovery mitigations. For icing hazards, avoidance can take the form of avoiding flight into icing conditions or avoiding the hazard of icing by making the aircraft tolerant to icing conditions. Icing detection mitigations can take the form of detecting icing conditions or detecting early performance degradation caused by icing. Recovery from icing induced LOC requires flight crew or automated systems capable of accounting for reduced aircraft performance and degraded control authority during the recovery maneuvers. In this report we review the icing induced LOC accident mitigations defined in a recent LOC study and for each mitigation describe a research topic required to enable or strengthen the mitigation. Many of these research topics are already included in ongoing or planned NASA icing research activities or are being addressed by members of the icing research community. These research activities are described and the status of the ongoing or planned research to address the technology needs is discusse

Evaluating GaN Doherty architectures for 4G Picocells, WiMax and microwave backhaul links

This paper evaluates the Doherty power amplifier architecture in terms of linearity, efficiency and design solutions. As case study four different prototypes are presented, one for 4G Picocells at 2.1 GHz, one for WiMax applications at 3.5 GHz and two for point-to-point microwave backhaul radiolinks at 7 GHz. Experimental results together with design guidelines are discussed addressing strengths and weaknesses of the Doherty architectur

A high efficiency 10W MMIC PA for K-b and satellite communications

This paper discusses the design steps and experimental characterization of a monolithic microwave integrated circuit (MMIC) power amplifier developed for the next generation of K-band 17.3–20.2 GHz very high throughput satellites. The technology used is a commercially available 100-nm gate length gallium nitride on silicon process. The chip was developed taking into account the demanding constraints of the spacecraft and, in particular, carefully considering the thermal constraints of such technology, in order to keep the junction temperature in all devices below 160°C in the worst-case condition (i.e., maximum environmental temperature of 85°C). The realized MMIC, based on a three-stage architecture, was first characterized on-wafer in pulsed regime and, subsequently, mounted in a test-jig and characterized under continuous wave operating conditions. In 17.3–20.2 GHz operating bandwidth, the built amplifier provides an output power >40 dBm with a power added efficiency close to 30% (peak >40%) and 22 dB of power gain

The challenge and response to global tourism in the post-modern era: the commodification, reconfiguration and mutual transformation of Habana Vieja, Cuba

There is a growing literature on the symbolic and cultural meanings of tourism and the ways in which cities are increasingly competing for tourists through the promotion of cultural assets and different forms of spectacle in the `tourist bubble'. To date, research on the role and impact of tourism in cities has largely been confined to those in Western, post-industrial economies. This paper examines the growth of cultural tourism in the central area of Havana, Cuba, and explores the range of unique, devolved, state-owned enterprises that are attempting to use tourism as a funding mechanism to achieve improvements in the social and cultural fabric of the city for the benefit of residents. The paper concludes with an assessment of the implications of this example for our understanding of how the pressures for restructuring and commodification can be moderated at the city level. Copyright 2008 SAGE Publications. All rights reserved. Not for commercial use or unauthorized distribution

Persistent homology to analyse 3D faces and assess body weight gain

In this paper, we analyse patterns in face shape variation due to weight gain. We propose the use of persistent homology descriptors to get geometric and topological information about the configuration of anthropometric 3D face landmarks. In this way, evaluating face changes boils down to comparing the descriptors computed on 3D face scans taken at different times. By applying dimensionality reduction techniques to the dissimilarity matrix of descriptors, we get a space in which each face is a point and face shape variations are encoded as trajectories in that space. Our results show that persistent homology is able to identify features which are well related to overweight and may help assessing individual weight trends. The research was carried out in the context of the European project SEMEOTICONS, which developed a multisensory platform which detects and monitors over time facial signs of cardio-metabolic risk

Effect of eplerenone on parathyroid hormone levels in patients with primary hyperparathyroidism: a randomized, double-blind, placebo-controlled trial

<p>Abstract</p> <p>Background</p> <p>Increasing evidence suggests the bidirectional interplay between parathyroid hormone and aldosterone as an important mechanism behind the increased risk of cardiovascular damage and bone disease observed in primary hyperparathyroidism. Our primary object is to assess the efficacy of the mineralocorticoid receptor-blocker eplerenone to reduce parathyroid hormone secretion in patients with parathyroid hormone excess.</p> <p>Methods/design</p> <p>Overall, 110 adult male and female patients with primary hyperparathyroidism will be randomly assigned to eplerenone (25 mg once daily for 4 weeks and 4 weeks with 50 mg once daily after dose titration] or placebo, over eight weeks. Each participant will undergo detailed clinical assessment, including anthropometric evaluation, 24-h ambulatory arterial blood pressure monitoring, echocardiography, kidney function and detailed laboratory determination of biomarkers of bone metabolism and cardiovascular disease.</p> <p>The study comprises the following exploratory endpoints: mean change from baseline to week eight in (1) parathyroid hormone(1–84) as the primary endpoint and (2) 24-h systolic and diastolic ambulatory blood pressure levels, NT-pro-BNP, biomarkers of bone metabolism, 24-h urinary protein/albumin excretion and echocardiographic parameters reflecting systolic and diastolic function as well as cardiac dimensions, as secondary endpoints.</p> <p>Discussion</p> <p>In view of the reciprocal interaction between aldosterone and parathyroid hormone and the potentially ensuing target organ damage, the EPATH trial is designed to determine whether eplerenone, compared to placebo, will effectively impact on parathyroid hormone secretion and improve cardiovascular, renal and bone health in patients with primary hyperparathyroidism.</p> <p>Trial registration</p> <p>ISRCTN33941607</p

Design principles in housing for people with complex physical and cognitive disability: towards an integrated framework for practice

To develop a research-based environmental framework to guide the design and construction of suitable residential dwellings for individuals with complex disability. An environmental approach to housing design and development recognises that there are physical, psychological and social components relating to housing design, dwelling location and the neighbourhood context, and that these elements interact to affect the physical, psychological, and social wellness of individuals. Following theoretical review and synthesis, a comprehensive set of design features that are conducive to residents’ wellness and quality of life are described. It is clear that housing design and development for people with complex disability ought to consider the physical, social, natural, symbolic, and care environment in relation to housing design, dwelling location, and the neighbourhood context for improved housing outcomes. An integrated housing design and development framework is presented. It is hoped this practical matrix/evaluative tool will inform future inclusive housing design and development decisions in Australia and internationally. The application of this framework is especially relevant to political climates striving to achieve design innovation to increase housing choice for people with complex disability

C-reactive protein reference percentiles among pre-adolescent children in Europe based on the IDEFICS study population

OBJECTIVES: C-reactive protein (CRP) is involved in a wide range of diseases. It is a powerful marker for inflammatory processes used for diagnostic and monitoring purposes. We aimed to establish reference values as data on the distribution of serum CRP levels in young European children are scarce. SUBJECTS: Reference values of high-sensitivity CRP concentrations were calculated for 9855 children aged 2.0-10.9 years, stratified by age and sex. The children were recruited during the population-based European IDEFICS study (Identification and prevention of Dietary-and lifestyle-induced health Effects in Children and infantS) with 18 745 participants recruited from 2007 to 2010. RESULTS: In 44.1 % of the children, CRP values were below or equal the detection limit of 0.2 mg/l. Median CRP concentrations showed a slight negative age trend in boys and girls, whereas serum CRP values were slightly higher in girls than in boys across all age groups. CONCLUSIONS: Our population-based reference values of CRP may guide paediatric practice as elevated values may require further investigation or treatment. Therefore, the presented reference values represent a basis for clinical evaluation and for future research on risk assessment of diseases associated with increased CRP levels among children

Surface and interface investigation of a 15th century wall painting using Multispectral Imaging and Pulse-Compression Infrared Thermography

Before starting the restoration of an artwork, good practice involves the evaluation of the item healthiness possibly carried out through non-invasive techniques. In the specific case of painting inspection, hyper- and multi- spectral techniques are commonly used to analyze the outer layers (varnish, pictorial, and drawing), while X-ray, tomography, and many others can be employed to investigate its inner structure. Although highly desirable, a single technique providing all the information about a painting is still not available. Thus, it is of great interest to define the analysis’ protocols that could optimally exploit the complementarities of a minimal set of techniques. To this aim, the present paper shows the combined use of the hypercolorimetric multispectral imaging and pulse-compression thermography on a 15th century wall painting attributed to the Italian artist Antonio del Massaro, also known as Pastura, representing the Madonna with the Child and the Saints Jerome and Francis. The capabilities and the complementarities of the two techniques, whose information can also be fused through post-processing, are illustrated in detail in this paper. In addition, a false-colour imaging approach is proposed to improve the readability and analysis of the thermography results

Imaging diagnostics coupled with non-invasive and micro-invasive analyses for the restoration of ethnographic artifacts from French Polynesia

In this paper, two different objects from the ethnographic collection of the museum of the Congregation of the Sacred Hearts of Jesus and Mary (Rome), a Polynesian barkcloth (tapa) and a Polynesian headdress in feathers (pa’e ku’a), were investigated to characterize the materials, to evaluate their state of conservation and address the restoration activities. Imaging methods such as multispectral imaging, 3D ultraviolet induced fluorescence and scanning electron microscopy have been integrated with analytical techniques such as X-ray fluorescence spectroscopy, Fourier transform infrared and surface enhanced Raman spectroscopy. Imaging investigations allowed us to differentiate constitutive materials and study their distribution, such as the yellow dye in the tapa used to trace the geometrical pattern and the psittacofulvins responsible for the feathers’ colors in the headdress. The combination of molecular spectroscopy, supported by observation under a scanning electron microscope, allowed us to propose a characterization of the organic painting materials (Morinda citrifolia, Curcuma longa) used for the tapa, and of the type of feathers (from Vini kuhlii bird) and vegetal fibers (Cocos nucifera L.) used to realize the headdress, as well as enabling the identification of degradation products and microorganisms affecting the artifacts before restoration. Fourier transform infrared spectroscopy detected the organic materials used as adhesives for the tapa and headdress: a polysaccharide, probably starch, for the tapa and a natural rubber from Cerbera manghas L. for the headdress. The results of the multi-analytic diagnostic campaign enabled the choice of proper restoration materials, compatible with the original ones, and helped us develop effective protocols for the artifacts’ conservation, such as laser cleaning of the feathers