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The standard modular Equatorial Port Plug (EPP) in ITER is at its final stage of design. It serves as common platforms for different diagnostics systems which are integrated together in three cassettes called Diagnostic Shielding Module (DSM). The equatorial port #12 will host an EPP with six diagnostics: the Visible-Infrared Camera and the H-α Monitor integrated in DSM #1, the Glow Discharge Wall Conditioning, the Radial X-rays Camera and the Hard X-rays Monitor, installed in DSM #2 and the Core Thomson Scattering in DSM #3. The EPP should not only serve as a diagnostic port, but also it has to provide the necessary shielding to allow for maintenance in port interspace and in port cell. This work is devoted to nuclear analyses performed to assess the nuclear loads and the shielding performance of the system. A very detailed neutronic model of EPP #12 has been developed and integrated in a 40° ITER sector MCNP model (C-model). The implemented model has been used to evaluate the neutron and gamma flux distributions, nuclear heating, radiation induced damage, tritium and helium concentration at the ITER end of life in the port plug area.

[EN] A Banach space X has the so-called ball-covering property whenever its unit sphere can be covered by a countable collection of open balls that miss the origin. If 0 < alpha < 1, then X has the alpha-ball covering property if those balls miss alpha B-x. We show that X is separable if and only if X can be renormed such that the dual (X, vertical bar parallel to . parallel to vertical bar)* enjoys the alpha-BCP for some (or all) alpha is an element of (0,1). In contrast with this, we observe that the separability of X does not always imply the BCP of the dual X*. The latter fact follows from a general example: non-separable C(K)* spaces fail the BCP in a major way - they even fail the "(-1)-BCP". (C) 2019 Elsevier Inc. All rights reserved., The first-named author was supported by AEI/FEDER (project MTM2017-83262-C2-2-P of Ministerio de Economía y Competitividad), by Fundación Séneca, Región de Murcia (grant 19368/PI/14), and Universitat Politècnica de València. The second-named author was supported by the Estonian Research Council (grant PUTJD670) and partially by the Estonian Ministry of Education and Research (institutional research funding IUT20-57). The second named author would like to thank the Instituto Universitario de Matemática Pura y Aplicada of the Universitat Politècnica de València for the excellent working conditions during his stay there in 2018. The third-named author was supported by AEI/FEDER (project MTM2017-83262-C2-1-P of Ministerio de Economía y Competitividad) and Universitat Politècnica de València. The authors would like to thank the referee for the comments that improved the paper.

The Diagnostic Shielding Modules (DSM) are secondary containers of the ITER diagnostic Port Plugs where shielding and diagnostics components have to be integrated together. For the development of Equatorial Port DSMs several key requirements have to be met by the Port Integrators. First of all, the total dry Plug weight must not exceed the allowable weight (currently 48 ton) in order to guarantee the consistency with the specification of other interfacing systems involved in the Port Plugs maintenance. Secondly, a shielding capability able to limit Shut-Down Dose Rate in the Interspace Zone (man access corridors) below 100 μSv/h needed to allow the human accessibility for the Port Plug sealing disassembly, the inspection and the maintenance of diagnostic components behind the Plug closure plate and in the interspace. Finally, Remote Handling (RH) compatibility for refurbishment of the Port Plug and maintenance of systems integrated is necessary as well. These operations involve activated components that are processed in the Hot Cell. As a result of these demands, the ITER Port Integration team has developed the so called Modular Equatorial DSM able to answer the weight/shielding/RH requirements described above following the ALARA principle and offering a standard infrastructure for the common DSM integration problems.

This paper presents analysis of neutronic effects carried out with the newly developed MCNP model of the ITER Upper Port (UP) environment integrated into the neutronics C-Model of the ITER tokamak machine. C-Model includes only the standard ITER components and generic port plugs. With a number of other important updates in addition to the description of the UP environment, the new C-Model R180430 has been issued 30/04/2018, and currently is the ITER-reference model to be used in any ITER-related neutronics analysis. One of ITER’s design targets is to maintain a limit of 100 μSv/h for Shut-Down Dose Rate (SDDR) after 12 days of cooling time in the areas of envisaged personnel access with hands-on maintenance. In case of UP, the maintenance access is planned inside of UP duct where Inter-Space Structure (ISS) will be installed. Therefore, neutronics analysis has been focused on estimations of SDDR inside the UP duct and, following the ALARA principle, on finding the UP design solutions for reduction of dose. This task has been accomplished by 3D visualization of the SDDR map at UP duct, and drawing SDDR isosurfaces which revealed areas of dose hot spots and the radiation streaming pathways. Such information allows an understanding of the weak areas of the UP shielding and the formulation of the means for potential improvement of the radiation conditions in the UP duct area. The R2Smesh code has been used in SDDR calculations, with capability to plot distributions of decay gamma sources and revealing which radioactive materials are dominant contributors to SDDR. Comparison with the previous version of the ITER generic model called C-lite V2R150304MOD shows that the newly created C-Model R180430 demonstrated similar SDDR at the UP ISS maintenance corridors.

Highlights • The serum IL-6 level is the best marker for the severity of COVID-19 of those tested. • IL-6 values greater than 35 pg/mL can differentiate between mild and severe COVID-19. • High serum IL-6 values are associated with increased risk of mortality and ICU admission., The clinical presentation of COVID-19 is very heterogeneous, ranging from asymptomatic to severe, which could lead to the need for mechanical ventilation or even death.We analyzed the serum levels of IL-6 in patients with COVID-19 diagnosis and its relationship with the severity of the disease, the need for mechanical ventilation and with patient mortality. We assessed IL-6 in a cohort of 50 patients diagnosed with COVID-19 pneumonia with different degrees of disease severity, and compared it with clinical and laboratory findings. We found higher levels of IL-6 in patients with more severe pneumonia according to CURB-65 scale (p = 0.001), with ICU mechanical ventilation requirements (p = 0.02), and who subsequently died (p = 0.003). Of the clinical and analytical parameters analyzed in the current study, the serum levels of IL-6 was the most effective predictor of disease severity. From the data obtained in ROC curve analysis, we defined a cut-off point for serum IL-6 levels of 35 pg/mL above which both the risk of mortality (OR = 20.00, 95 % CI 4.214-94-912, p = 0.0001) and ICU admission (OR = 12.750, 95 % CI 2,159-75,3,3, p = 0.005) were increased. Starting from blood IL-6 levels 27 out of 50 patients, with high levels and more severe symptoms, were treated with the IL-6 receptor antagonist Tocilizumab. IL-6 serum levels appear to be a useful prognostic biomarker in patients with a diagnosis of COVID-19 pneumonia. A cut-off point of 35 pg/mL could clearly differentiate patients a with more severe disease.

ITER is a critical step in the development of fusion energy: its role is to confirm the feasibility of exploiting magnetic confinement fusion for the production of energy for peaceful purposes by providing an integrated demonstration of the physics and technology required for a fusion power plant. Rapid progress is being made in project construction, and the facility is now taking shape at St-Paul-lez-Durance in southern France. In the course of designing and manufacturing of the systems making up the ITER tokamak and the ITER facility, extensive ground-breaking R&D has been implemented by the ITER partners across a wide range of technology and science areas which underpin the achievement of the project’s engineering and fusion plasma performance requirements. Significant developments have been made in the production of high performance Nb3Sn superconducting strand and in magnet technologies supporting the construction of the largest superconducting magnets produced to date. High heat flux plasma facing components have been fabricated which are capable of sustaining quasi-stationary heat loads of up to 10 MW m−2 and transient loads of up to 20 MW m−2. Fusion nuclear technologies such as remote maintenance and tritium breeding have received specific emphasis within the ITER R&D program, since extensive deployment of these technologies is foreseen. Diagnostic systems face particular challenges in the ITER environment, and wide-ranging R&D activities have been implemented to develop novel solutions to ensure an adequate measurement capability in ITER DT operation. Routine and reliable operation in ITER will require a highly effective capability for the detection, avoidance and mitigation of disruptions, and significant science and technology R&D is underway to establish this capability. The overall integration of the control requirements for the ITER plasma and facility, in particular during burning plasma operation, has presented new challenges for fusion control systems, including the need for robust safety and hardware (investment) protection. These challenges are being addressed via the implementation of the most extensive and ambitious control system to date. The paper introduces the ITER project and its major goals in relation to the development of fusion energy and provides an overview of key innovations which have been made in these areas of fusion technology and science in support of ITER construction.

Most of ITER's diagnostics will be provided with viewing lines (optical, microwave, and spectroscopic) for the monitoring of key characteristics of the plasma or for the achievement of physical measurements inside the vacuum vessel. The nature of the physical signal transmitted through the viewing lines requires the implementation of window assemblies incorporating nonmetallic window. Placed at the vacuum boundary, the window assembly shall also ensure the vacuum integrity required for the plasma. Moreover, the diagnostic window assemblies form part of the ITER primary confinement boundary, and thus, directly related to the nuclear safety. This paper gives an overview of their design and related on-going engineering assessments by analysis or tests in the final design phase.

The ITER electron cyclotron emission (ECE) diagnostic system has primary roles in providing measurements of the core electron temperature profile and the electron temperature fluctuation associated with the neoclassical tearing modes. The ITER ECE system includes a radial and oblique line-of-sight. Four 43-meter long low-loss transmission lines (TLs) are designed to transmit millimeter wave power in the frequency range of 70–1000 GHz in both X- and O-mode polarization from the port plug to the ECE instrumentation room in the diagnostic building. The measurement instrumentation includes two Fourier transform spectrometer (FTS) systems and two radiometer systems. The Indian Domestic Agency (IN-DA) and United States Domestic Agency share the responsibility. The IN-DA scope excluding instrumentation and control has passed its preliminary design review and is progressing towards the final design review (FDR). In parallel, the diagnostic integration in different areas is ongoing. Several captive components for the TLs have passed FDR and will be manufactured for installation in the tokamak building soon. A peer review meeting has been held on the prototype hot calibration source, and its integration and new thermal analysis in the diagnostic shield module are continuing. A prototype TL is being tested. A prototype polarizing Martin-Puplett type FTS, operating in the frequency range 70–1000 GHz, features an in-vacuo fast scanning mechanism and a cryo-cooled dual-channel THz detector system. Its performance has been assessed in detail against ITER requirements.

[EN] In Fabian et al. (Arch Math (Basel) 78(6):459-464, 2002) it was proved that, if a Valdivia compact space K has property P a property defined in terms of the Gateaux differentiability of certain norms on C(K)then, under a cardinality condition on the density character, C(K) is a weakly Lindelof determined space, and in particular, K is Corson. We prove here that the result holds in general without cardinality restrictions. Moreover, the proof given here is much simpler than the original one., We thank the referee for suggestions that helped to improve the preliminary version of the manuscript. The first-named author was supported by AEI/FEDER (project MTM2017-83262-C2-2-P of Ministerio de Economia y Competitividad), by Fundacion Seneca, Region de Murcia (grant 19368/PI/14), and Universitat Politecnica de Valencia. The second-named author was supported by the Estonian Research Council (grant PUTJD670) and partially by the Estonian Ministry of Education and Research (institutional research funding IUT20-57). The third-named author was supported by AEI/FEDER (project MTM2017-83262-C2-1-P of Ministerio de Economia y Competitividad) and Universitat Politecnica de Valencia.

The Port Plug handling system aims to insert and remove the ITER Port Plugs installed at the Equatorial and Upper levels of the ITER Tokamak. As the Port Plugs activation and contamination levels prevent hands-on access, their safe transfer is ensured by the Cask and Plug Remote Handling System (CPRHS) between the buildings. The basic principle of the CPRHS is to allow the transfer of the Plug in and out the vessel using passive guiding means permanently attached to the Plug and the Vessel. This handling process has been reproduced on a scaled-down physical mock-up which has partially demonstrated its reliability from a mechanical point of view. In parallel, a campaign of tribology testing has been performed to identify suitable material compatible with the In-Vessel environmental conditions and with which to optimize the coefficient of friction. This paper describes the technical activities performed during handling process development (integration, tolerances, mechanical and neutronic analyses) and the results of performed tests.

In this work, the D1SUNED code has been used to characterize the shutdown dose rate (SDDR) in the ITER Upper Port (UP) interspace due to activation induced by two neutron sources: plasma prompt neutrons and 17N decay neutrons emitted from the activated cooling water conducted through the UP. Furthermore, shielding measures have been proposed to mitigate the SDDR in the UP interspace; a set of conceptual shields has been designed and inserted into the MCNP computational model C-lite v2 covering the Vacuum Vessel UP Stub Extension and the UP Connecting Duct. The results have shown that the integration of proposed shields has significantly decreased the SDDR due to the activation induced by plasma prompt neutrons, while the activation induced by 17N decay neutron has a negligible contribution to the total SDDR in the ITER UP interspace.

ITER is the world’s largest fusion device currently under construction in the South of France with >50 diagnostic systems to be installed inside the port plugs (PPs), the interspace (IS), or the port cell region of various diagnostic ports. The plasma facing diagnostic first wall (DFW) and its supporting diagnostic shield modules (DSM) are designed to protect front-end diagnostics from plasma neutron and plasma radiation, while providing apertures for diagnostic access to the plasma. The design of ITER port plug structures including the DFW and the DSM is largely driven by the electromagnetic loads included on the PP structural components during plasma major disruptions and the vertical displacement events (VDEs). Unlike DFW and DSM, the design of diagnostic system, however, is likely driven by the steady-state thermal loads from plasma volumetric and surface heating and the dynamic response of the in-port components attached to the port-specific DSM or closure plate under transient loads induced on the vacuum vessel and the port extension during asymmetric VDEs. Three tenant diagnostic systems are integrated into the equatorial port 09. The toroidal interferometer/polarimeter, or TIP system, is installed in the left drawer (DSM3, left looking from plasma) for measuring the plasma density so to control the fuel input. The electron cyclotron emission (ECE) system is installed in the middle drawer (DSM2) to provide the high spatial and temporal resolution measurements of electron temperature evolution and the electron thermal transport inferences. The visible/infrared wide angle viewing system is installed in the right drawer (DSM1) to provide visible and infrared viewing and temperature data of the first wall for its protection in support of machine operation. The port plug integration design and multiphysics analyses are performed following port integration requirements including the weight limit (45 tones total), shut down dose rate limits, the cooling/heating and structural integrity validation. Mass distribution for TIP and ECE DSMs has been optimized to minimize the total weight by a new design of the boron carbide shielding pocket. The lightened DSM maintains its front-end load distribution and the structural stiffness with minimum impact to the DFW so to better protect on-board diagnostics; while still provides sufficient front-end stiffness for its structural integrity as well as the diagnostics function requirements.

In the framework of ITER diagnostics, the visible and infrared equatorial Wide Angle Viewing System (WAVS, referenced as 55.G1.C0 in ITER Plant Breakdown Structure) plays a key role. Indeed, this system is devoted to monitor the surface temperature of the plasma facing components by infrared thermography and to image the edge plasma emission in the visible range. As a consequence, it is mandatory to verify that WAVS components are able to withstand all the foreseen loads and load combinations. This paper is dedicated to present the methods and results of electromagnetic (EM) and Transient Structural (TS) analyses for determining the loads due to Eddy Currents and the associated stresses and displacements in the in-vessel components of WAVS at its Preliminary Design Review (PDR) stage. Specifically, the analysed WAVS in-vessel components comprise First Mirror Units, shutters and Hot Dog Legs of the EPP#12 (Equatorial Port Plug). The selected EM loads derive from the IO-assumed worst EM scenario for EPP#12 (specifically a plasma exponential major disruption). Given the variation maps of the global magnetic field in the regions of interest during the transient, the EM loads have been estimated using a local 3D EM model of the WAVS components by means of the ANSYS Electromagnetics Suite v.19.2, employing the tool ANSYS Maxwell. Successively, the obtained results have been used as inputs to the corresponding TS analyses (carried out using ANSYS Workbench v.19.2). Therefore, the related outcomes can be combined with the set of all other structural studies (i.e. thermal and seismic analyses) to assess the overall mechanical behaviour of the components under study for the WAVS PDR level. Moreover, the results obtained have shown how EM loads are often design driving loads for the WAVS components.

ITER is the world’s largest fusion device currently under construction in South of France with 50+ diagnostic systems installed inside the port plugs, the interspace or the port cell region of various diagnostic ports. The plasma facing Diagnostic First Wall (DFW) and its supporting Diagnostic Shielding Modules (DSM) are designed to protect the front-end diagnostics from plasma neutron and radiation while providing apertures for diagnostic access to the plasma. The design of ITER port plug (PP) structure assembly including the DFWs, DSMs with in-port diagnostics is largely driven by the electromagnetic (EM) loads induced on these passive structural components during plasma disruptions, and the steady-state thermal loads from plasma volumetric and surface heating during normal operations. The design is significantly influenced by the dynamic response of in-port components attached to the port-specific DSM or PP closure plate as a result of transient EM loads induced on the PP assembly, vacuum vessel (VV) and the port extension during asymmetric plasma Vertical Displacement Events (VDEs). We investigate in this study the worst plasma disruption load cases for diagnostic systems of varying size and location, and summarize the steady-state thermal, transient EM and VV inertial loads for ITER diagnostic systems.

During the final design review of Diagnostic Port Plugs, it has been highlighted that the current system of fixation, based on gaps, while it is not harmful for the port plug, it throws large uncertainties over the alignment of the optical systems placed inside the DSMs at the same time that the real mechanical behavior of the assembly is clearly unknown. Because the DSM is not rigidly fixed to the Port Plug structure, the DSM and its internal components suffer, during abnormal events like seismic or electromagnetic disruptions, an important level of amplification on the accelerations induced. This magnification is largely derived from a rattling effect that the DSM is vibrating inside the port plug. This effect produces an increase of the efforts acting on the anchoring components of the port plug at the same time that the final position of the DSM after an abnormal event is unknown and greatly influenced by the manufacturing and assembly tolerances. In order to solve all these issues, a new locking system has been developed based on a rigid configuration. Non-relevant modifications are required in the Port Plug structure or in the DSMs for the implementation of this new system because the interfaces are kept intact. Results based on this new configuration are available and they present an important attenuation of the induced accelerations on components inside the DSMs. In addition, the system permits the individual adjustment of each one of the interfacing component to finally achieve the correct aligned positions. Therefore, this new locking system has been assumed for all IO Diagnostic Port Plugs.

[EN] There is a maybe unexpected connection between three apparently unrelated notions concerning a given w*-dense subspace Y of the dual X* of a Banach space X: (i) The norming character of Y, (ii) the fact that (Y, w*) has the Mazur property, and (iii) the completeness of the Mackey topology mu(X, Y), i.e., the topology on X of the uniform convergence on the family of all absolutely convex w*-compact subsets of Y. To clarify these connections is the purpose of this note. The starting point was a question raised by M. Kunze and W. Arendt and the answer provided by J. Bonet and B. Cascales. We fully characterize mu(X, Y)-completeness or its failure in the case of Banach spaces X with a w*-angelic dual unit ball in particular, separable Banach spaces or, more generally, wealdy compactly generated ones-by using the norming or, alternatively, the Mazur character of Y. We characterize the class of spaces where the original Kunze-Arendt question has always a positive answer. Some other applications are also provided. (C) 2016 Elsevier Inc. All rights reserved., Supported in part by MICINN (Project MTM2014-57838-C2-2-P).

The ITER Vacuum Vessel Sectors have very tight tolerances and high density of welding. Therefore, prediction and reduction of welding distortion are critical to allow the final assembly with the other Vacuum Vessel Sectors without the production of a full scale prototype. In this paper, the effect of the welding sequence in the distortions inside a fixed manufacturing route and in a highly constrained assembly is studied in the poloidal segment named inboard (PS1). This is one of the four poloidal segments (PS) assembled for the sector. Moreover, some restrictions and limitations in the welding sequence related to the manufacturing process are explained. The results obtained show that the effect of the sequence is lower in a highly constrained assembly than in a low constrained one. A prototype manufactured by AMW consortium (PS1 mock-up) is used in order to validate the finite element method welding simulation employed. The obtained results confirmed that for Electron-Beam welds, both the welding simulation and the mock-up show a low value of distortions.

The ITER Electron Cyclotron Emission (ECE) diagnostic is progressing towards its Preliminary Design Review (PDR). In parallel, the diagnostic integration in the Equatorial Port is ongoing. Port Integration has to address the structural integrity to withstand various loads, maintenance and the safety aspects of ECE diagnostic. The ITER ECE system includes radial and oblique lines-of-sight. Recently, a successful peer-review of the in-port plug Hot Calibration Source has taken place and its performance and integration feasibility has been demonstrated. Four 45-meter long low-loss transmission lines are designed to transmit mm-wave power in the frequency range of 70- 1000 GHz in both X- and O-mode polarization from the port plug to the ECE instrumentation room in the diagnostic building. Prototype transmission lines are being tested [1]. A prototype polarizing Martin-Puplett type Fourier Transform Spectrometer (FTS) operating in the frequency range 70-1000 GHz, has a fast scanning mechanism and a cryo-cooled dual-channel THz detector system. Its performance has been tested as per ITER requirements. Assessment of the instrumentation and control requirements, functional and non-functional requirements, operation procedures, plant automation are ongoing for the PDR. The current status of the diagnostic, together with integration activities, is presented.

[EN] We study the class of Banach spaces X such that the locally convex space (X, mu(X,Y)) is complete for every norming and norm-closed subspace Y subset of X*, where mu(X, Y) denotes the Mackey topology on X associated to the dual pair < X, Y >. Such Banach spaces are called fully Mackey complete. We show that fully Mackey completeness is implied by Efremov's property (epsilon) and, on the other hand, it prevents the existence of subspaces isomorphic to l(1)(omega(1)). This extends previous results by Guirao et al. (2017) [9] and Bonet and Cascales (2010) [3]. Further examples of Banach spaces which are not fully Mackey complete are exhibited, like C[0, omega(1)] and the long James space J(omega(1)). Finally, by assuming the Continuum Hypothesis, we construct a Banach space with w*-sequential dual unit ball which is not fully Mackey complete. A key role in our discussion is played by the (at least formally) smaller class of Banach spaces X such that (Y, w*) has the Mazur property for every norming and norm-closed subspace Y subset of X*. (C) 2019 Elsevier Inc. All rights reserved., The authors wish to thank A. Aviles for valuable discussions on the topic of this paper. They are also grateful to the referee for his/her comments and suggestions. A.J. Guirao was supported by projects MTM2017-83262-C2-1-P (AEI/FEDER, UE) and 19368/PI/14 (Fundacion Seneca). G. Martinez-Cervantes and J. Rodriguez were supported by projects MTM2014-54182-P and MTM2017-86182-P (AEI/FEDER, UE) and 19275/PI/14 (Fundacion Seneca).

This is a survey around a property (Property \(\mathscr {P}\)) introduced by M. Fabian, V. Zizler, and the third named author, in terms of differentiability of the norm. Precisely, a Banach space X is said to have property \({\mathscr {P}}\) if for every norming subspace \(N\subset X^*\) there exists an equivalent Gâteaux differentiable norm for which N is 1-norming. Every weakly compactly generated space has property \({\mathscr {P}}\). Applications to measure theory, the classification of compacta, and some other structural properties of compact and Banach spaces are given. Some open problems are listed, too. It is based on an earlier paper by Fabian, Zizler, and the third named author, and a recent one by the authors of the survey.

The generic upper port plug (GUPP) structure in ITER is a 6 m long metal box which deploys diagnostic components into the vacuum vessel. This structure is commonly used for all the diagnostic upper ports. The final design of the GUPP structure, which has successfully passed the final design review in 2013, is described here. The diagnostic port plug is cantilevered to the vacuum vessel with a heavy payload at the front, so called the diagnostic first wall (DFW) and the diagnostic shield module (DSM). Most of electromagnetic (EM) load (∼80%) occurs in DFW/DSM. Therefore, the mounting design to transfer the EM load from DFW/DSM to the GUPP structure is challenging, which should also comply with thermal expansion and tolerance for assembly and manufacturing. Another key design parameter to be considered is the gap between the port plug and the vacuum vessel port. The gap should be large enough to accommodate the remote handling of the heavy port plug (max. 25 t), the structural deflection due to external loads and machine assembly tolerance. At the same time, the gap should be minimized to stop the neutron streaming according to the ALARA (as low as reasonably achievable) principle. With these design constraints, the GUPP structure should also provide space for diagnostic integration as much as possible. This requirement has led to the single wall structure having the gun-drilled water channels inside the structure. Furthermore, intensive efforts have been made on the manufacturing study including material selection, manufacturing codes and French regulation related to nuclear equipment and safety. All these main design and manufacturing aspects are discussed in this paper, including requirements, interfaces, loads and structural assessment and maintenance.

This paper demonstrates structural integrity of the first confinement boundary in Generic Upper Port Plug structures against cracking during service. This constitutes part of the justification to demonstrate that the non-aggression to the confinement barrier requirement may be compatible with the absent of a specific in-service inspections (ISI) program in the trapezoidal section. Since the component will be subjected to 100% volumetric inspections it can be assumed that no defects below the threshold of applied Nondestructive Evaluation techniques will be present before its commissioning. Cracks during service would be associated to defects under Code acceptance limit. This limit can be reasonably taken as 2 mm. Using elastic–plastic fracture mechanics an initial defect is postulated at the worst location in terms of probability and impact on the confinement boundary. Its evolution is simulated through finite element analysis and final dimension at the end of service is estimated. Applying the procedures in RCC-MR 2007 (App-16) the stability of the crack is assessed. As relative high safety margin was achieved, a complementary assessment postulating an initial defect of 6 mm was also conducted. New margin calculated provides a more robust design.

Due to this position close to the plasma, the port plug structure and the diagnostic first wall (DFW) contain water to allow cooling during operation and for heating during bake-out. To remove the heat coming from the plasma due to radiation and neutrons, the pressure inside these structures should be up to 44 bars. On the other hand, the dominant load expected to drive the design of these structures is of electromagnetic origin during the plasma disruption. Description of the loads acting on DFWs and generic port plug structures and the significance of the load due to the water pressure, with implications on the design and inspection, are discussed in this paper.

The ITER Vacuum Vessel (VV) features upper, equatorial and lower ports. The upper and regular equatorial ports are occupied by the port plugs. Although the port design has been overall completed in the past, the design of some remaining interfaces was still in progress: in particular, the Sealing Flange package, which includes the high-vacuum seals and the plug fasteners. As the ITER construction phase has started, the procurement of the VV ports has been launched. The VV upper ports will be procured by the Russian Federation Domestic Agency. The main suppliers were selected and the manufacturing design of the first parts is in full progress now. Since the VV is classified at nuclear level N2, the design and manufacture of its components are to be compliant with the French RCC-MR code and regulations for nuclear pressure equipment in France. These regulations make a strong impact to the port design and manufacturing process.

The purpose of this paper is present an overview of the methodology followed to calculate the dynamic amplification factors applied to the electromagnetic loads acting in the ITER generic port plugs. The methodology used for combining an EM transient event with another kind of load is based in the treated of this dynamic EM event as a static load. As first stage a transient dynamic analysis was performed, at the most demanded electromagnetic event [2] , to determine the dynamic response of the port plugs. In the same way, have been solved all the time steps of the dynamic event as static loads, it means that the inertial effect has been neglected. The response of each time-step at the dynamic solution has been compared with the same time-step solved as a static load. For this purpose some control points were positioned along the structure at the most representative locations. The key of these calculations is the understanding of the deformed modes affecting the port plug in order to obtain a reasonable dynamic amplification factors that permit the characterization of these loads in a realistic way and does not derive in a too conservative approach. Additionally, the fundamental frequencies and vibration modes of the generic port plug, requested for the characterization of the damping effects at the structure, were calculated in a complementary modal analysis performed for this aim.

The ITER equatorial port plugs are submitted to a drained weight limit of 45 T. This limitation can conflict with their radiation shielding demands, although some weight margin is being discussed. The port interspaces are subject to a shutdown dose rate limit of 100 µSv h−1 after 106 s of cooling time. To meet it, the port plugs must show a neutron flux attenuation comparable to their neighborhood, despite considering penetrations to host systems. Most of this task relies on the drawer shield module (DSM). In this work, two DSM concepts are analyzed with this perspective: the box-based DSM and the modular DSM. Regardless the penetrations, the box-based DSM leads to unsatisfactory port plugs to meet both weight and SDDR requirements. On the contrary, the modular DSM shows a performance which allows for the adoption of such DSM concept, or equivalent, a port may comply with both requirements at the same time, provided the penetrations are well designed.

[EN] The Bishop-Phelps-Bollobas property deals with simultaneous approximation of an operator T and a vector x at which T nearly attains its norm by an operator T-o and a vector x(o), respectively, such that T-o attains its norm at x(o). In this note we extend the already known results about the Bishop-Phelps Bollobas property for Asplund operators to a wider class of Banach spaces and to a wider class of operators. Instead of proving a BPB-type theorem for each space separately we isolate two main notions: Gamma-flat operators and Banach spaces with ACK(rho) structure. In particular, we prove a general BPB-type theorem for Gamma-flat operators acting to a space with ACK(rho) structure and show that uniform algebras and spaces with the property beta have ACK(rho) structure. We also study the stability of the ACK(rho) structure under some natural Banach space theory operations. As a consequence, we discover many new examples of spaces Y such that the Bishop-Phelps-Bollobas property for Asplund operators is valid for all pairs of the form (X, Y)., The research of the first, second and third authors was partially supported by MINECO grant MTM2014-57838-C2-1-P and Fundacion Seneca, Region de Murcia grant 19368/PI/14. The research of the third author is done in frames of Ukrainian Ministry of Science and Education Research Program 0115U000481. The research of the fourth author has been partially performed during her stay in University of Murcia in frames of Erasmus+ program. We thank the referee for his/her suggestions that helped to improve the original manuscript.

[EN] We use the smooth variational principle and a standard renorming to give a short direct proof of the classical Bishop-Phelps-Bollobas theorem on the density of norm-attaining functionals for weakly compactly generated Banach spaces. Then we show that a slight adjustment of a known Preiss-Zajfcek differentiability argument provides a simple, useful characterization of individual norms on separable Banach spaces admitting residual sets of norm-attaining functionals in terms of Frechet differentiability of their dual norms., This research was partly supported by MICINN and FEDER Projects MTM2014-57838-C2-1-P, MTM2014-57838-C2-2-P. The first named author was also partly supported by Fundacion Seneca, Region de Murcia grant 19368/PI/14.

To determine the current status of the patients operated on for hypospadias in our region, in order to adapt the surgical technique to their real needs.A descriptive and observational study. Interviews were conducted with hypospadias surgery patients in our hospital between 1976 and 1996, focusing on their urinary and sexual function and psychological impact. We performed a descriptive statistical analysis and comparisons between types of hypospadias (SPSSv19).566 patients were operated on for hypospadias during the study period, interviewing 100 aged between 18 and 40 years. The 73% were distal and 27% proximal. Of all patients, 30% do not have an orthotopic meatus, 10% have fistula, 18% have some degree of stenosis and 52% have penile curvature. The 13% feel to have had disadvantages in their life. They consider they have a different penis in: size (19%), glans shape (17%), curvature (14%), scars (10%) and lowest hole (7%). Sexual satisfaction was valued at 8.9 on a scale of 1 to 10, with no differences between the types of hypospadias. Proximal hypospadias patients have more ejaculation problems: 42% versus 11% in distal hypospadias. The 68% of the proximal ones would like to improve compared to 20% of the distal in: appearance (17%), size (11%) and way to urinate (11%).Anatomic abnormalities are maintained but the aspects that values the adult patient differ from those persecuted by practiced surgeries. A significant percentage of patients would try to get another surgery. Keeping the size of the penis and natural appearance of the glans should be a priority in hypospadias surgery.Conocer el estado actual de los pacientes intervenidos por hipospadias en nuestra región, para adaptar la técnica quirúrgica a sus necesidades reales.Estudio descriptivo y observacional. Se entrevistó a pacientes intervenidos de hipospadias en nuestro hospital entre 1976 y 1996, incidiendo en su función urinaria, sexual e impacto psicológico. Realizamos análisis estadístico descriptivo y comparaciones entre tipos de hipospadias (SPSSv19).566 pacientes fueron intervenidos de hipospadias en el período estudiado, entrevistándose a 100, con edades entre 18 y 40 años. El 73% fueron distales y 27% proximales. En el 30% el meato no es ortotópico, 10% presenta fístula, 18% presenta algún grado de estenosis y 52% presenta curvatura. El 13% siente haber tenido desventajas en su vida. Consideran su pene diferente en: tamaño (19%), forma glande (17%), curvatura (14%), cicatrices (10%) y orificio más bajo (7%). La satisfacción sexual fue valorada en 8,9 en una escala del 1 al 10, sin diferencias entre los tipos de hipospadias. Los proximales presentan mayores problemas de eyaculación: 42% frente al 11% de los distales. El 68% de los proximales desearían mejorar frente al 20% de los distales, en apariencia (17%), tamaño (11%) y forma de orinar (11%).Se mantienen alteraciones anatómicas pero los aspectos que más valora el paciente adulto difieren de los perseguidos en las cirugías que se practicaban. Un porcentaje importante de pacientes se reoperaría de nuevo. Mantener el tamaño del pene y aspecto natural del glande debe ser un objetivo prioritario durante la cirugía de hipospadias.

The outer vessel steady-state sensors (OVSS) – a subsystem of the ITER magnetic diagnostics – will contribute to the measurement of the plasma current, plasma-wall clearance, and local perturbations of the magnetic flux surfaces near the wall. The diagnostic consists of a poloidal array of sixty sensors welded to the vacuum vessel outer surface. Each OVSS contains a pair of bismuth Hall sensors with the measurement axes parallel (in the poloidal plane) and normal to the vacuum vessel. These Hall sensors were successfully tested in environmental conditions corresponding to those in ITER (neutron irradiation, vacuum vessel bakeout, etc.) and have proven to be capable of measuring the magnetic field up to at least ±7 T. An AC analogue lock-in current spinning signal processing electronics has been developed for the OVSS to eliminate the spurious voltage due to Hall sensor manufacturing imperfections and the planar Hall effect. This paper presents the final design of the OVSS diagnostic, developed jointly by the ITER Organization and the Institute of Plasma Physics in Prague.

Generic Equatorial Diagnostic First Wall (GEDFW) as a plasma facing component of ITER sustains heavy thermal load from plasma radiation and nuclear load. Cooling circuit of GEDFW has been proposed and meanwhile cooling performance is assessed through thermal hydraulic analysis. Heat transfer capability is regarded as an important property in GEDFW design and is usually validated by numerical analyses. Hydraulic analysis and thermal analysis were performed individually and then solved by thermal coupling. Hydraulic analysis was performed to obtain the heat transfer coefficient (HTC) and bulk temperature which were initial conditions in thermal analysis. Thermal analysis provided the wall temperature for the next hydraulic analysis iteration and the thermal hydraulic iteration proceeds until the residual of surface temperature approached preset tolerance. Temperature map obtained through thermal hydraulic analysis which has demonstrated the heat transfer capability of GEDFW.

We study the Bishop–Phelps–Bollobas property for numerical radius within the framework of C ( K ) spaces. We present several sufficient conditions on a compact space K ensuring that C ( K ) has the Bishop–Phelps–Bollobas property for numerical radius. In particular, we show that C ( K ) has such property whenever K is metrizable.

The ITER Vacuum Vessel (VV) primary function is to enclose the plasmas produced by the ITER Tokamak. Since it acts as the first radiological barrier of the plasma, it is classified as a class 2 welded box structure, according to RCC-MR 2007. The VV is made of an inner and an outer D-shape, 60 mm-thick double shell connected through thick massive bars (housings) and toroidal and poloidal structural stiffening ribs. In order to provide neutronic shielding to the ex-vessel components, the space between shells is filled with borated steel plates, called In-Wall Shielding (IWS) blocks, and water. In general, these blocks are connected to the IWS ribs which are connected to adjacent housings. The development of a Finite Element model of the ITER VV including all its components in detail is unaffordable from the computational point of view due to the large number of degrees of freedom it would require. This limitation can be overcome by using submodelling techniques to simulate the behaviour of the bolted ribs assemblies. Submodelling is a Finite Element technique which allows getting more accurate results in a given region of a coarse model by generating an independent, finer model of the region under study. In this paper, the methodology and several simulations of the VV bolted ribs assemblies using submodelling techniques are presented. A stress assessment has been performed for the elements involved in the assembly considering possible types of failure and including stress classification and categorization techniques to analyse the critical sections. In particular, studies to optimise the number of bolts on each specific VV area have been developed to assess the compliance with RCC-MR 2007 requirements. It is shown as well that the submodelling technique is a powerful tool to avoid the current computational limitations.

Absrtract The components located inside the ITER vacuum chamber (in-vessel components – IC), due to their specific nature and the environments they are exposed to (neutron radiation, high heat fluxes, electromagnetic forces, etc.), have specific design criteria which are, in this paper, referred as Structural Design Criteria for In-vessel Components (SDC-IC). The development of these criteria started in the very early phase of the ITER design and followed closely the criteria of the RCC-MR code. Specific rules to include the effect of neutron irradiation were implemented. In 2008 the need of an update of the SDC-IC was identified to add missing specifications, to implement improvements, to modernise rules including recent evolutions in international codes and regulations (i.e. PED). Collaboration was set up between ITER Organization (IO), European (EUDA) and Russian Federation (RFDA) Domestic Agencies to generate a new version of SDC-IC. A Peer Review Group (PRG) composed by members of the ITER Organization and all ITER Domestic Agencies and code experts was set-up to review the proposed modifications, to provide comments, contributions and recommendations.

The as-welded surfaces of the ITER Vacuum Vessel sectors need to be within a very tight tolerance, without a full-scale prototype. In order to predict welding distortion and optimize the manufacturing sequence, the industrial contract includes extensive computational simulations of the weld processes which can rapidly assess different sequences. The accurate shape prediction, after each manufacturing phase, enables actual distortions to be compared with the welding simulations to generate modified procedures and pre-compensate distortions. While previous mock-ups used heavy welded-on jigs to try to restrain the distortions, this method allows the use of lightweight jigs and yields important cost and rework savings. In order to enable the optimization of different alternative welding sequences, the simulation methodology is improved using condensed computation techniques with ANSYS in order to reduce computational resources. For each welding process, the models are calibrated with the results of coupons and mock-ups. The calibration is used to construct representative models of each segment and sector. This paper describes the application to the construction of the Vacuum Vessel sector of the enhanced simulation methodology with condensed Finite Element computation techniques and results of the calibration on several test pieces for different types of welds.

To analyze clinical and electromyographic treatment outcome of dysfunctional voiding (DV) with animated Biofeedback (Bfb). Clinical or electromyographic variables associated with higher success rate were checked.Cross-sectional study of patients with DV, that in 2010- 2015 followed animated Bfb program. Efficacy was measured with Uroflowmetry, Electromyography (EMG) and validated clinical questionnaire. Inclusion criteria: no myelodysplasia, no anatomical malformations and a minumin of 3 Bfb sessions. Clinical variables: age, number of sessions, daytime leaks, nocturnal enuresis, constipation, UTI, VUR. Flow measurement variables: morphology of curves, electromyogram, flows, and elevated post void residual (PVR).Of 37 patients who received Bfb, 27 girls who met inclusion criteria were selected. Mean age: 7.8 years (2.5). Twelve (44%) had detrusor overactivity on urodynamics concomitantly. Globally, all clinical and flowmetry parameters improved. Clinically 33.5% had complete resolution of symptoms, 37% improved ( 50% of symptoms according to criteria ICCS) and 29% had no improvement. In EMG, 74% achieved normal perineal relaxation. Constipation at baseline is associated with lower rates of success (cure: 13 vs. 58%, p = 0.019; cure + improvement: 60% vs. 83% p 0.05). The absence of RPM at the end of the study was associated with clinical improvement (cure: 66.7% vs. 0%, p = 0.012; cure + improvement: 89% vs. 60%, p 0.05).Bfb in DV provides cure or improvement and electromyographic resolution are 69 and 74% respectively. The absence of constipation is associated with higher success rates. The High RPM correlates with persistence of clinics.Se pretende analizar resultado clínico y electromiográfico del tratamiento de la micción disfuncional (MD) con Biofeedback (Bfb) animado. Además, se estudia si existen variables clínicas o electromiográficas asociadas a mayor tasa de éxito.Se realizó corte transversal de pacientes con MD, que en 2010- 2015 siguieron programa de Bfb animado. El control post-tratamiento se realizó con Uroflujometría más Electromiografía y cuestionario validado. Se excluyeron los pacientes con mielodisplasia, malformaciones anatómicas, y a los que recibieron menos de 3 sesiones. Las variables clínicas estudiadas fueron: edad, número de sesiones, fugas diurnas, enuresis nocturna, estreñimiento, ITU, RVU. Las flujométricas fueron: morfología de curvas, electromiograma, flujos, y residuo postmiccional (RPM) elevado.De 37 pacientes que recibieron Bfb, se seleccionaron 27 niñas que cumplieron criterios de inclusión. Edad media: 7,8 años (DE: 2,5). Doce (44%) presentaron hiperactividad del detrusor asociado a la MD. De manera global, todos los parámetros clínicos y flujométricos mejoraron. Clínicamente 33,5% presentó resolución completa de síntomas y el 37% mejoraron (desaparecieron más del 50% de los síntomas según criterios ICCS). El 29% no presentó mejoría. Electromiográficamente el 74% logró flujometrías normales. El estreñimiento al inicio del estudio se asocia a tasas menores de éxito (curación: 13 vs. 58%, p= 0,019; curación + mejoría: 60% vs. 83% p 0,05). La ausencia de RPM al final del estudio se relacionó con la mejoría clínica (curación: 66,7% vs. 0%, p= 0,012; curación + mejoría: 89% vs. 60%, p 0,05).El Bfb en la micción disfuncional proporciona tasas de curación/mejoría clínica y de resolución electromiográfica del 69 y 74%, respectivamente. La ausencia de estreñimiento se asocia a mayores tasas de éxito. La persistencia de clínica se relaciona con RPM elevado post-tratamiento.

There are few studies on the long term follow up of pyeloplasty. Is there a residual pelvis dilatation in all successful procedures? How is the long term evolution of the ecographic parameters and measures postoperatively (PO)?We reviewed all successful Anderson-Hynes pyeloplasties performed on obstructed renal pelvis with an anterio-posterior diameter15 mm during 2001-2010. Ultrasound controls were made at 3 and 6 months postoperatively and then yearly afterwards. We aimed to describe time course of hydronephrotic changes following unilateral pyeloplasties, using three parameters: pelvic anterior-posterior diameter (APD), pelvis/córtex ratio (P/C R) and the percentage of improvement in APD (PI-APD).41 patientswereincluded. Age at intervention ranged from 2 months to 10.3 years (mean 13 months, 83% were operated in the first year of life). Median of follow up was 4 years (range 1-12 years). Mean APD preoperatively was 25 mm (range 16-54). At the third month PO, PI-APD was 28%. At the sixth month control, it was 51%, and remained stable during the next consecutive yearly controls, without statistically significant variations (50%, 57%, 60%, 51%, 39%, 46%, 38%, 42%). P/C R diminished significantly already in the third month control (4.6 vs. 1.8, p=0.03). We observed complete disappearance of hidronephrosis in 8 patients (19.5%).Although early postoperative ultrasound changes occur, the ultrasound parameters remain often stable during long term follow up. We documented the complete normalization of renal pelvis (no hydronephrosis) in one of every five patients.Hay pocos estudios sobre la evolución postquirúrgica a largo plazo de la estenosis de la unión pieloureteral (EUPU). ¿Existe una dilatación residual en todos los pacientes que presentan resultados satisfactorios tras la cirugía? ¿Cuál es la evolución en los parámetros ecográficos?Revisión retrospectiva de pacientes con EUPU intrínseca, con diámetro anteroposterior (AP) de la pelvis15 mm (e hidronefrosis grado III o superior), y seguidos tras pieloplastia de Anderson-Hynes en el periodo 2001-2010 (10 años), no reintervenidos, asintomáticos y con función renal normal. Los controles ecográficos se hicieron a los 3 y 6 meses postoperatorio (PO) y posteriormente anuales. Se midieron tres parámetros: diámetro AP, ratio pelvis/córtex (R P/C) y porcentaje de mejoría (PM).Se seleccionaron 41 pacientes, intervenidos entre 2 meses y 10,3 años (media 13 meses, 83% en primer año de vida), mediana de seguimiento: 4 años (rango: 1-12). El diámetro AP de la pelvis renal medio pre-quirúrgico fue de 25 mm (rango 16-54). A los 3 meses la disminución media del diámetro AP (o PM) fue del 28% (respecto a diámetro prequirúrgico). A los 6 meses PO, fue del 51%, permaneciendo estable durante los siguientes años: 50%, 57%, 60%, 51%, 39%, 46%, 38%, 42% (controles anuales durante los primeros 8 años). La relación pelvis/córtex disminuyó de manera significativa ya en las ecografías al tercer mes (4,6 vs. 1,8; p= 0,03). En 8 pacientes (19,5%) se pudo objetivar ausencia de dilatación piélica en la evolución.Aunque los cambios ecográficos tras la pieloplastia se pudieron objetivar desde los controles precoces, permanecieron a menudo sin cambios durante los controles posteriores. Sin embargo, en uno de cada cinco pacientes se objetivó la desaparición de la dilatación piélica.

Surgical site infection (SSI) has a considerable impact on neonatal morbidity. There are known risk factors such type of surgery (clean/contaminated), prematurity, surgical length, hypoalbuminemia, previous infection, prolonged mechanical ventilation, and so on. Many perioperative factors have not been studied, opposite to adults. We have developed a survey on intraoperative attitudes and measures, as surgical wound management in Neonates among pediatric surgeons, to seek for a wider consense.Multi-response survey with 22 items, based on the Surgical Infection Society NIH 2008 clinical guideline. Each item poses a question on perioperative attitudes, surgical aspects and wound management. Each question is subdivided in two categories, depending on urgency and type of surgery (clean/contaminated).159 surveys were sent. Among those, we received back 51 (32%). 69% of the interviewed surgeons use clorhexidin to prepare surgical field, 25% use Iodine solutions. 69% never use diathermy to incise skin. There was no agreement on the use of sterile plastic adhesive drapes, intra-cavity lavage, changing surgical gloves/material, or wound irrigation during closure. 82% never use cyanocrilate dressing. Intracuticular skin suture and simple stitches were used indistinctly. Wound management and dressings were not uniform and depended on each pediatric unit.The survey reflects the lack of consensus regarding prophylactic measures and wound management among pediatric surgeons who care after surgical neonates.La infección de herida quirúrgica (IHQ) es una causa frecuente de morbimortalidad en Neonatología. Existen factores de riesgo conocidos: tipo de cirugía (sucia/contaminada/limpia), prematuridad, duración de intervención, hipoalbuminemia, infección previa, ventilación mecánica prolongada y contaminación de vía central. Otros factores perioperatorios no han sido estudiados en neonatos, sí en adultos. Desarrollamos una encuesta sobre las actitudes y las medidas, intraoperatorias y de manejo de herida. Pretendemos dilucidar si existe consenso sobre la profilaxis de IHQ neonatal.Encuesta con 22 ítems, basada en la guía de prevención de la IHQ en adultos (Surgical Infection Society, 2008). Cada ítem cuestiona temas sobre hábitos perioperatorios, intra y postoperatorios, relacionados con el manejo de la herida quirúrgica en el neonato, y consta de dos preguntas, según sea cirugía sucia/urgente o limpia/contaminada. Las opciones de respuesta son 4: siempre, con frecuencia, raramente y nunca. Enviamos la encuesta a cirujanos pediátricos españoles mediante correo electrónico en el primer trimestre del 2012.Se enviaron 159 encuestas. 51 (32%) respondieron. 69% emplean clorhexidina para preparar campo, 25% usan povidona iodada. Solo el 51% refirió dejar actuar siempre un minuto el antiséptico. 69% nunca usan bisturí eléctrico en piel para ampliar herida. No hubo respuestas unánimes en cuanto al uso de paños adhesivos protectores del campo, la irrigación de planos con suero o antisépticos durante el cierre, el empleo de drenajes, cambio de guantes y/o material al iniciar el cierre (cirugía sucia). El 72% y el 82% nunca emplean cianocrilato como cierre o apósito en neonatos, respectivamente. En cirugía sucia, 43% suturan piel con intradérmica y 49% con puntos sueltos.La distribución de respuestas refleja la falta de consenso sobre los aspectos de la técnica quirúrgica y el manejo perioperatorio que podrían estar relacionados con la profilaxis de IHQ neonatal.

In the historical series, the diagnostic yield of lumbosacral magnetic resonance imaging to rule out occult spinal dysraphism (or occult myelodysplasia), requested by paediatric urology, ranged from 2% to 15%. The aim of this study was to define our cost-effectiveness in children with urinary symptoms and to define endpoints that increase the possibility of finding occult spinal dysraphism.A screening was conducted on patients with urinary dysfunction for whom an magnetic resonance imaging was requested by the paediatric urology clinic, for persistent symptoms after treatment, voiding dysfunction or other clinical or urodynamic findings. We analysed clinical (UTI, daytime leaks, enuresis, voiding dysfunction, urgency, renal ultrasonography, lumbosacral radiography, history of acute urine retention, skin stigma and myalgia) and urodynamic endpoints (hyperactivity or areflexia, voiding dysfunction, interrupted pattern, accommodation value and maximum flow). A univariate analysis was conducted with SPSS 20.0.We analysed 21 patients during the period 2011-2015. The median age was 6 years (3-10). Three patients (14.3%) had occult spinal dysraphism: one spinal lipoma, one filum lipomatosus and one caudal regression syndrome with channel stenosis. The endpoints with statistically significant differences were the myalgias and the history of acute urine retention (66.7% vs. 5.6%, P=.04; OR= 34; 95%CI: 1.5-781 for both endpoints).The diagnostic yield of magnetic resonance imaging requested for children with urinary dysfunctions without skin stigma or neuro-orthopaedic abnormalities is low, although nonnegligible. In this group, the patients with a history of acute urine retention and muscle pain (pain, «cramps») can experience a greater diagnostic yield or positive predictive value.