The lack of ME in the esophageal distal biopsies of FH patients indicates a limited role of these histological abnormalities in symptom generation in them. ME can be considered as an accurate and reliable diagnostic marker for distinguishing FH patients from GERD patients and has the potential to be used to guide the correct therapy.

Abstract. The world market of mobile robotics is expected to increase substantially in the next 20 yr, surpassing the market of industrial robotics in terms of units and sales. Important fields of application are homeland security, surveillance, demining, reconnaissance in dangerous situations, and agriculture. The design of the locomotion systems of mobile robots for unstructured environments is generally complex, particularly when they are required to move on uneven or soft terrains, or to climb obstacles. This paper sets out to analyse the state-of-the-art of locomotion mechanisms for ground mobile robots, focussing on solutions for unstructured environments, in order to help designers to select the optimal solution for specific operating requirements. The three main categories of locomotion systems (wheeled – W, tracked – T and legged – L) and the four hybrid categories that can be derived by combining these main locomotion systems are discussed with reference to maximum speed, obstacle-crossing capability, step/stair climbing capability, slope climbing capability, walking capability on soft terrains, walking capability on uneven terrains, energy efficiency, mechanical complexity, control complexity and technology readiness. The current and future trends of mobile robotics are also outlined.

Our findings demonstrate that Faringel is well-tolerated and effective in reducing heartburn by modifying esophageal acid exposure time, number of acid refluxes and their proximal migration.

LQT is as sensitive as LBT in detecting lactase deficiency; however, it seems to be more accurate than LBT in predicting the clinical response to a lactose-free diet.

PurposeThe purpose of this paper is to describe the development of a robot for surveillance able to move in structured and unstructured environments and able to overcome obstacles with high energetic efficiency.Design/methodology/approachThe proposed Epi.q‐TG hybrid robot combines wheeled and legged locomotion. It is equipped with four three‐wheeled locomotion units; traction is generated by the two forecarriage units, while the two rear ones have same geometry but are idle. Each front unit is actuated by a single motor with the interposition of an epicyclical gearing, accurately designed in order to suitably switch between wheeled and legged motion. The robot changes locomotion mode from rolling on wheels (advancing mode) to stepping on legs (automatic climbing mode) according to local friction and dynamic conditions.FindingsThe experimental results confirm the design objectives. In advancing mode, the robot behaves like a four‐wheeled vehicle, with high speed and energetic efficiency. In automatic climbing mode, the robot can walk on uneven and soft terrains and overcome steps with remarkable height with respect to its dimensions (up to 84 per cent of the locomotion unit height).Practical implicationsBesides surveillance, Epi.q‐TG can be successfully used in many tasks in which it is useful to combine the advantages of wheeled and legged locomotion, e.g. unmanned inspection of nuclear and chemical sites, minesweeping, and intervention in disaster zones.Originality/valueThe core of the project is the epicyclical mechanism of the locomotion unit, which switches between advancing mode and automatic climbing mode without control action. This solution limits the control and actuation complexity and consequently the robot cost, widening the range of possible applications.

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Abstract\ud Purpose – Aims to discuss how a Cartesian parallel robot with flexure revolute joints can effectively perform miniaturized assembly tasks.\ud Design/methodology/approach – The results of the test and validation phase of a Cartesian parallel robot designed for miniaturized assembly are\ud shown. The workspace volume is a cube with 30mm side and the target accuracy is 1mm. Each of the three robot legs has a prismatic-planar\ud architecture, with a cog-free linear motor and a planar joint realized using ten superelastic flexure revolute joints. Flexure joints are adopted in order to\ud avoid stick-slip phenomena and reach high positioning accuracy; their patented construction is relatively low-cost and allows a quick replacement in\ud case of fatigue failure.\ud Findings – The tests on the prototype are very encouraging: the measured positioning accuracy of the linear motors is ^0.5mm; on the other hand,\ud the effects of unwanted rotations of flexure joints and hysteresis of the superelastic material are not negligible and must be properly compensated for in\ud order to fully exploit the potential performance of the machine.\ud Practical implications – The introduction of this robotic architecture can fulfil the needs of a wide range of industrial miniaturized assembly\ud applications, thanks to its accurate positioning in a relatively large workspace. The cost of the machine is low thanks to its extreme modularity.\ud Originality/value – The combination of Cartesian parallel kinematics, cog-free linear motors and superelastic flexure revolute joints allows one to\ud obtain very good positioning performance

This paper discusses the application of a particular fractional-order control scheme, the PDD1/2, to the position control of a micrometric linear axis. The PDD1/2scheme derives from the classical PD scheme with the introduction of the half-derivative term. The PD and PDD1/2schemes are compared by adopting a nondimensional approach for the sake of generality. The linear model of the closed-loop system is discussed by analysing the pole location in theσ-plane. Then, different combinations of the derivative and half-derivative terms, characterized by the same settling energy in the step response, are experimentally compared in the real mechatronic application, with nonnegligible friction effects and a position set point with trapezoidal speed law. The experimental results are coherent with the nonlinear model of the controlled system and confirm that the introduction of the half-derivative term is an interesting option for reducing the tracking error in the transient state.