Francesco Rea

Restoration of body composition in celiac children after one year of gluten-free diet.

Restoring protein, fat, and bone compartments in celiac children on a gluten-free diet (GFD) is not yet well understood. Hence, anthropometric, biochemical, and bone densitometric assessment was performed in 23 celiac children, 8 boys and 15 girls, aged 1 to 12 years (mean 4.7), at diagnosis and 1 year after GFD. At diagnosis the patients had height, arm muscle area, triceps skinfolds, subscapular skinfolds, fat area index, and bone mineral content significantly lower than in an age- and sex-matched control group. After 1 year on GFD, no significant difference was found between patients and controls in all the parameters studied except in height and arm muscle area, which, however, were very near to the normal expected. Serum hemoglobin, iron, and zinc values were below the normal range in more than one half of patients at diagnosis and within the normal range in almost all of them after 1 year of GFD. Serum hemoglobin, iron, zinc, triglycerides, proteins, albumin, and calcium values significantly rose during the year of GFD. A year of GFD in celiac children allows a virtually complete return in body mass composition.

Weight overgrowth of coeliac children on gluten-free diet

Abstract Linear and weight growth were assessed in 17 coeliac children on gluten-free diet and followed up for 2 to 7 years (mean 3.8). Mean height was −0.85 height standard deviation scores at first visit, −0.19 after one year and 0.03 at last visit. Weight for Height Index (WHI) was 88.8% at first visit, 111.9 after one year and 111.6 at last visit. WHI values of patients at one year and at last visit were significantly higher than the 100% expected, even after excluding the subjects having at least one parent with body mass index >30 and/or at least one sibling with WHI >120%. A dietary recall at the end of the follow-up revealed an excess in caloric, animal protein and lipid intake and an absolute or relative deficit in complex sugars and vegetal proteins. The exclusion of gluten containing foods from the diet of coeliac children carries the risk of intake of hypercaloric foods, which may lead to some degree of obesity.

Effect of gluten-free diet on bone mineral metabolism of celiac children

Abstract Studies on the effects of gluten-free diet (GFD) on bone mineral metabolism have given no univocal results in children and adults with celiac disease. Bone mineral metabolism was assessed in 23 celiac children, aged 1 to 12 years (mean 4.6) at moment of diagnosis (T 0 ) and after 12 months of GFD (T 12 ) without any vitamin D supplementation. At T 0 , calcium, phosphates and alkaline phosphatase values were within the normal range in all but few subjects, but their respective average values significantly rose at T 12 . The percentages of low values of bone mineral density and of osteocalcin at T 0 were significantly higher than those at T 12 and their respective average values significantly increased between T 0 and T 12 . Circulating parathyroid hormone values were within the normal range in all patients at T 0 and T 12 , with no significant difference in average values between T 0 and T 12 . One year of GFD is sufficient to obtain a complete restoration of bone mineral density even without vitamin D supplementation. The normal levels of parathyroid hormone and the reduced osteocalcin at diagnosis suggest that in young celiac children there is no important rise in bone remodeling.

Modal stability assessment for a morphing aileron subjected to actuation system failures: Numerical analysis supported by test evidence

The meaningful growth process and the exponential development related to aircraft industry has currently introduced new requirements concerning the fuel burn reduction and the noise emitted. The awareness on meeting the comfort targets implied a significant evolution of the assessments in aircraft design, aimed at reducing the problems that have emerged in empirical investigations. The aircraft renewal process involves targeted technical choices both to careful observance of safety as to the market requirements. In the current “low-noise” research scenario on a global scale, the morphing technology is playing a dominant role for the many benefits available in the greening of the next generation air transport. The research project CRIAQ-MDO505, born by an intense synergy among industries, research centers and universities has allowed for investigating morphing structures potentials through the design and manufacturing of a variable camber aileron tailored for CS-25 category aircraft applications. In this framework, the authors focused on the setup of an advanced finite element model (FEM) and on its validation through ground resonance tests performed on a true-scale prototype. A very good correlation between numerical and experimental modal parameters was proven thus showing the adequacy of the adopted modelling strategies as well as the reliability of the FEM. Relying upon the validated FEM, sensitivity modal analyses were carried out to evaluate the stability of results with respect to single and combined failures of the actuation line enabling morphing. Modal parameters pertinent to each failure scenario were arranged into a rational database for further studies on the aero-servo-elastic behavior of the morphing system.

Actuation and control of a novel wing flap architecture with bi-modal camber morphing capabilities

Modern aerospace research programs are increasingly oriented towards adaptive wing structures for greening the air transport in the near future. New structural concepts implementing and integrating innovative technologies are mandatory for succeeding in this critical task. Among these, the so-called morphing structures are taken into account in aerospace applications, since they ensure the structural shape control in order to optimize the aerodynamic efficiency during the different flight phases. Among the most ambitious research projects launched in Europe, the JTI - Green Regional Aircraft (GRA) is placed in foreground for the design and the demonstration of a true-scale morphing flap applicable to the Natural Laminar Flow (NLF) wing of a 130-seats reference aircraft belonging to EASA CS25 category. In this framework, the authors intensively worked on the definition of a specific actuation and control system layout properly enabling two flap operational modes: overall camber morphing in deployed configuration, during take-off and landing, to enhance high lift performances; upwards and downwards deflection of the flap trailing edge (nearly the 10% of the local chord) in stowed configuration, to improve wing aerodynamic efficiency in cruise. For this purpose, a digital logic control law was opportunely implemented into controller devices by using LTI DriveManager® software. Obtained results have been presented in terms of controlled morphed shapes, showing an excellent correlation with respect to the target geometries imposed by design requirements.

Chapter 10 – Active Metal Structures

Abstract Morphing of metallic wing structures has fascinated generations of researchers; numerous and sometimes bizarre architectures have been proposed, tailored to specific end-applications and aircraft type. Although different for layout, all of them can be categorized in two basic groups: mechanized architectures and compliant mechanisms. Mechanized architectures implement morphing through the rigid-body motion of stiff subcomponents interconnected by suitably designed kinematic chains and actuation leverages. Each subcomponent of the kinematic chain is sized to provide its own contribution to the adsorption of the external solicitations arising in operative conditions; actuators and actuation transmission line are sized to enable the motion of the system and to preserve given shape configurations while counteracting aerodynamic loads with the minimum need of power. Compliant mechanisms involve the deformation of structural elements to enable the required shape-change; mechanical properties of the structure have to be properly distributed in order to assure adequate morphing compliance and adequate stiffness to withstand external loads. In this chapter, the design philosophy behind each type of morphing structure has been presented, together with practical applications to wing trailing edge camber adaptation. By referring to similar end-application, the adopted design strategies and obtained outcomes are compared, thus better highlighting the advantages and weak points of each morphing solution.

Control strategy of an electrically actuated morphing flap for the next generation green regional aircraft

The design and application of adaptive devices are currently ambitious targets in the field of aviation research addressed at new generation aircraft. The development of intelligent structures involves aspects of multidisciplinary nature: the combination of compact architectures, embedded electrical systems and smart materials, allows for developing a highly innovative device. The paper aims to present the control system design of an innovative morphing flap tailored for the next generation regional aircraft, within Clean Sky 2 – Airgreen 2 European Research Scenario. A distributed system of electromechanical actuators (EMAs) has been sized to enable up to three operating modes of a structure arranged in four blocks along the chord-wise direction: •overall camber-morphing; •upwards/downwards deflection and twisting of the final tip segment. A state-of-art feedback logic based on a decentralized control strategy for shape control is outlined, including the results of dynamic stability analysis based on the blocks rational schematization within Matlab/Simulink® environment. Such study has been performed implementing a state-space model, considering also design parameters as the torsional stiffness and damping of the actuation chain. The design process is flowing towards an increasingly “robotized” system, which can be externally controlled to perform certain operations. Future developments will be the control laws implementation as well as the functionality test on a real flap prototype.

Experimental shape reconstruction of a morphing wing trailing edge in simulated operative conditions

The common challenge of all aerospace advancements is greening the air transport. This led the recent research programs towards the study of “metamorphic” wing structures, capable of adapting their geometry to the different conditions of flight. The development of morphing structures allows the reduction of drag and the increase of range, together with the growth of load control effectiveness. In this context, the European research project SARISTU addressed the physical integration of smart and morphing structural concepts, by implementing them on a true scale outer wing belonging to a CS-25 category aircraft finally tested in a large Wind Tunnel. In the framework of SARISTU project, the design of an Adaptive Trailing Edge Device was developed. The morphing skin concept consisted of a segmented skin, with aluminum and silicone foam strips covered by a protective silicone top-layer. A two-bay demonstrator was tested inside the Wind Tunnel at the Department of Industrial Engineering of the University of Naples “Federico II”; experimental analyses were performed in order to verify whether the silicone parts could show out of plane bumps induced by the aerodynamic loads occurring during the Wind Tunnel test campaign. A photogrammetric optic approach was adopted, in order to reach the aforementioned targets in a non-invasive way; such methodology was selected due the high resolution assured at a very low implementation costs. Obtained results allowed to confirm the demonstrator well done design and opened the doors to the next experimental test campaign performed in TsAGI Russian Wind Tunnel, on the outer wing equipped with a five-bay demonstrator of the Adaptive Trailing Edge Device.

Aeroelastic analysis of an adaptive trailing edge with a smart elastic skin

Nowadays, the design choices of the new generation aircraft are moving towards the research and development of innovative technologies, aimed at improving performance as well as to minimize the environmental impact. In the current “greening” context, the morphing structures represent a very attractive answer to such requirements: both aerodynamic and structural advantages are ensured in several flight conditions, safeguarding the fuel consumption at the same time. An aeronautical intelligent system is therefore the outcome of combining complex smart materials and structures, assuring the best functionality level in the flight envelope. The Adaptive Trailing Edge Device (ATED) is a sub-project inside SARISTU (Smart Intelligent Aircraft Structures), an L2 level project of the 7th EU Framework programme coordinated by Airbus, aimed at developing technologies for realizing a morphing wing extremity addressed to improve the general aircraft performance and to reduce the fuel burning up to 5%. This specific stu...