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Objectives: Cyproheptadine is a first-generation H1-antihistamine drug first that was distributed in the 1960s. While its orexigenic effect was observed early, cyproheptadine is not yet authorized for this indication in all countries today. There is an increasing medical interest and demand for the orexigenic effect of cyproheptadine, especially in children with poor appetite. As cyproheptadine might be evaluated in future clinical trials, we wanted to assess its safety profile.Methods: Using the French national pharmacovigilance database, we retrospectively analyzed all pediatric and adult reports of adverse effects of cyproheptadine recorded since its first distribution in France. Next, we performed a systematic review of the literature of cyproheptadine adverse effects.Results: Since 1985, 93 adverse effects were reported in the French pharmacovigilance database (adults 81.7%, children 18.3%); these were mainly neurological symptoms (n = 38, adults 71%, children 28.9%), and hepatic complications (n = 15, adults 86.7%, children 13.3%). In the literature, the most frequent adverse effect reported was drowsiness in adults or children, and five case reports noted liver complications in adults. We estimated the frequency of hepatic adverse effects at 0.27 to 1.4/1000, regardless of age.Conclusion: Cyproheptadine can be considered a safe drug. Mild neurological effects appear to be frequent, and hepatotoxicity is uncommon to rare. Randomized controlled trials are needed to evaluate the safety and efficacy of cyproheptadine before authorization for appetite stimulation, especially in young children as studies at this age are lacking. Possible hepatic complications should be monitored, as very rare cases of liver failure have been reported.

IntroductionLow bone mineral density (BMD) is a frequent issue in children and adolescents with inflammatory bowel disease (IBD). Several studies in healthy populations have reported a positive impact of physical activity (PA) on bone health. Recently, an observational study in paediatric patients with IBD showed a significant positive relationship between daily PA and BMD. However, intervention studies investigating a causal relationship between PA and BMD are warranted to confirm these results. The aim of this randomised controlled trial will be to investigate the effect of a PA programme on BMD in paediatric patients with IBD.Methods and analysisThis trial is a multicentre (four centres), randomised, controlled, blinded end-point study. Eighty children with IBD will be randomly assigned in a 1:1 ratio to receive a programme with adapted physical exercises (intervention group) or usual PA (control group) during a 9-month period. The primary outcome is the change from baseline at 9 months (the end of the study) in whole-body BMD assessed by dual-energy X-ray absorptiometry. Secondary efficacy outcomes include the changes from baseline at 9 months in: BMD assessed in the lumbar spine and trochanter; daily PA (time spent in moderate-to-vigorous PA); body composition (fat mass and fat-free mass); fatigue resistance; quality of life and activity of IBD.Ethics and disseminationThe study was approved by the Research Ethics Committee in France (Comité de Protection des Personnes, Sud-Ouest and Outre-Mer III, Bordeaux, France, No 2018/27). All procedures will be performed according to the ethical standards of the Helsinki Declaration of 1975, as revised in 2008, and the European Union’s Guidelines for Good Clinical Practice. Written informed consent will be obtained from the parents or legal guardian and from the children. Research findings will be disseminated in peer-reviewed journals and scientific meetings.Trial registration numberNCT03774329.

International audience; The development and construction of self-scanning capability short-range ultrawideband (UWB) radar is forthcoming for the French Military for Defense. This paper is devoted to the presentation of the self-scanning radar principle and of the development, construction, and tests of the different blocks needed to implement the elementary part of the forthcoming radar. The elementary radiation source is composed of a microstrip line with photoconductive switches, an optical system to trigger the switches, a pulsed modulator used as bias voltage to load the line, and a UWB antenna to radiate high electric fields in a broad frequency band. The main proposed innovations are devoted to the integration of the photoconductive switches within the antenna and to the use of the pulsed modulator as bias source instead of a dc voltage source. This modulator allows considering the increase in the yield of the whole source as well as the increase in the radiation bandwidth. Experimental results are presented in order to compare the switching efficiency with a dc bias source against this pulsed modulator bias source. Finally, photoswitches triggered by an 80-ps/20-μJ laser source are able to generate monopolar or bipolar pulses in the kilovolt range with subnanosecond duration and a 33-MHz pulse repetition frequency. First radiated electric field results of the whole device are also reported. \textcopyright 2017 IEEE.

Optoelectronic devices triggered by a laser ∞ash and operating in linear switching regime allow the generation of short pulses with small time jitters (2ps typically). An Ultra Wide Band antenna array combining as many of this photoswitches as antennas has the advantage to increase the radiation power on one hand and to ofier the agility of the radiation beam on the other hand obtained by time delay of laser illumination. During the step of antenna design, it becomes important to take into account the photoswitch integration in order to increase the peak power and the frequency band of the generated output signal. This paper presents an equivalent model of photoswitch obtained with the transient solver of CST Microwave Studio coupled within CST Design Studio. The second part of this article is dedicated to the integration of a photoswitch even within the antenna.

The study presented in this article belongs within the context of a design of a new kind of short-range Ultra Wide-Band (UWB) Radar with an autonomous scanning capability. The generation of short pulses is performed with an optoelectronic device triggered by a laser flash and operating in linear switching mode. By adding as many optical systems as antennas, we create a transmitting array with increased radiated energy. Each of those elements are fed with bursts composed of UWB optogenerated pulses with a slightly different pulse repetition frequency allowing beam-scanning capability. This article presents in detail all the parts needed to implement the elementary radiation source and offers a mathematical method of calculation to trace back to the generated feeding signal.

A new ultrawide-band (UWB) antenna named the "scissors antenna" has been designed specially for transient ultrawide-band applications. The scissors antenna, which is composed of conducting wires, radiates ultrashort pulses with very low dispersion. The radiation of this antenna has been characterized by a transient measurement method suitable for characterizing UWB antennas with very low dispersion. After a presentation of the scissors antenna, this measurement method is described. The last part of the paper presents a comparison between the radiation characteristics of the scissors antenna obtained by the transient measurements and those obtained by the classical harmonic measurements.

International audience; This paper proposes two studies on a Shark antenna array, working in the frequency band [800MHz - 8GHz], in a configuration including N generators and N antennas. The first study deals with the evaluation of the performances of the array from the analyze of the transient performances of the elementary system "generator + antenna". The second study concerns the comparison of two arrays having the same surface area, but a different number of antennas thanks to a scaling method on the dimensions of the elementary antenna.

International audience; The conception of a novel Ultra-Wideband (UWB) antenna array, designed especially for transient radar applications through the frequency band (300 MHz-3 GHz), is proposed in this paper. For these applications, the elementary antenna must be compact and nondispersive, and the array must be able to steer in two dimensions. The geometry of the elementary antenna and its radiation characteristics are presented. The array beam steering is analyzed and a technique making the increase of the transient front-to-back ratio possible is described.

International audience; An ultra wideband radar system based on a coherent emission of an ultra-wideband antenna array using photoconductive switching devices is proposed. The triggering process is obtained by the excitation of semiconductor samples in linear mode using a picosecond laser source. The emitting antenna system and the receiving antenna developed by the Research Institute XLIM present some specific qualities suitable for radiation and measurement of ultrashort pulses. The optical control of the sources allows to sum the radiated power and to steer the transient radiation beam accurately. The experiments realized with this optoelectronic array validate these two concepts. Another way of improving these systems is proposed. It involves using bipolar pulse generators.

This paper deals with miniaturization techniques and radiating optimization on UWB antenna in order to make an antenna array. The hard point with size reduction of an antenna is the back radiation, the cross polarization and the antenna adaptation. Several methods to keep the antenna adapted to our bandwidth [300 MHz - 3 GHz] are studied. A detailed study of the travelling wave elementary antenna is proposed. Some techniques are applied to reduce back radiation and cross polarization by the use of slots in order to reduce back radiation and resistive loads in order to reduce surface current levels and side cross polarization.

We propose a novel ultrawideband (UWB) antenna designed specially for transient UWB radar applications. This work is a part of a new project concerning an optoelectronic UWB radar demonstrator with an array of four antennas. This project required the development of a new UWB antenna: the Valentine antenna. This antenna must be lighter and more compact in H-plane to allow the assembly of the array. This array must have a volume lower than 1 m3. This antenna, which is composed of curved metallic strips, radiates ultrashort pulses in the frequency band 300 MHz - 3 GHz with very low dispersion, a high gain and a low cross-polarization in the axial direction. The Valentine antenna must support 10kV of peak voltage. This paper describes the Valentine antenna and its main radiation characteristics

The laboratory XLIM has developed an impulse optoelectronic ultra-wide band antenna array for UWB radar applications. This paper presents this system in which photoconductive switches generating high voltage monopolar pulses and UWB antennas are associated. The control of the releasing delay of the sources via optic provides to sum the radiation power and to steer the transient radiation beam accurately. The experiments realized with this optoelectronic array validate these two concepts. We also propose another way of improvement of these systems by using bipolar pulse generators.

PULSAR is an Ultra Wide Band (UWB) short pulse Radar developed by the CELAR (French Technical Center forArmament Electronics) and the IRCOM (Research Institute of Microwave and Optical Communications) in order todetect foliage and ground concealed mines. An instrumentation measurement system has been designed andimplemented, in particular new 2D broad band antennas with a very low pulse distortion. The clutter suppression isbased on background subtraction and wavelet transforms. These data are used to obtain SAR ultra wide band images bytransient methods. The following discussion describes the device, the experimental results and the signal processingcurrently utilized. Future development efforts on this system (generator, acquisition means ) are detailed.At the same time a theoretical study is made to estimate target transient responses captured by the system. So a FDTDcode is modified to simulate buried objects detection by the radar.Keywords : land mine detection, ultra-wide band radar, SAR imagery, electromagnetic modeling, transient antenna.