The c.429_452 duplication of the ARX gene: a unique developmental-model of limb kinetic apraxia:

BACKGROUND: The c.429_452dup24 of the ARX gene is a rare genetic anomaly, leading to X-Linked Intellectual Disability without brain malformation. While in certain cases c.429_452dup24 has been associated with specific clinical patterns such as Partington syndrome, the consequence of this mutation has been also often classified as "non-specific Intellectual Disability". The present work aims at a more precise description of the clinical features linked to the c.429_452dup24 mutation. METHODS: We clinically reviewed all affected patients identified in France over a five-year period, i.e. 27 patients from 12 different families. Detailed cognitive, behavioural, and motor evaluation, as well as standardized videotaped assessments of oro-lingual and gestural praxis, were performed. In a sub-group of 13 ARX patients, kinematic and MRI studies were further accomplished to better characterize the motor impairment prevalent in the ARX patients group. To ensure that data were specific to the ARX gene mutation and did not result from low-cognitive functioning per se, a group of 27 age- and IQ-matched Down syndrome patients served as control. RESULTS: Neuropsychological and motor assessment indicated that the c.429_452dup24 mutation constitutes a recognizable clinical syndrome: ARX patients exhibiting Intellectual Disability, without primary motor impairment, but with a very specific upper limb distal motor apraxia associated with a pathognomonic hand-grip. Patients affected with the so-called Partington syndrome, which involves major hand dystonia and orolingual apraxia, exhibit the most severe symptoms of the disorder. The particular "reach and grip" impairment which was observed in all ARX patients, but not in Down syndrome patients, was further characterized by the kinematic data: (i) loss of preference for the index finger when gripping an object, (ii) major impairment of fourth finger deftness, and (iii) a lack of pronation movements. This lack of distal movement coordination exhibited by ARX patients is associated with the loss of independent digital dexterity and is similar to the distortion of individual finger movements and posture observed in Limb Kinetic Apraxia. CONCLUSION: These findings suggest that the ARX c.429_452dup24 mutation may be a developmental model for Limb Kinetic Apraxia

Failure analysis and lessons learned on LHC experiments crate and power supply equipment

The LHC accelerator's first long shutdown period (LS1), in 2013–2014, has given the experiments the opportunity to perform planned upgrade and maintenance activities on systems and equipment. It has also been the right time to conduct a preventive maintenance campaign on crate and power supply equipment which is foreseen to operate smoothly for another 4 to 8 years. This paper presents the lessons learned during the LS1 power supply preventive maintenance activities as well as an in-depth analysis of the most common failure modes and weaknesses encountered on the power supplies in the LHC experiments over the past years of operation

Grounding, Shielding and Power Distribution in LHCb

The LHC-b collaboration needs some basic rules on grounding, shielding and power distribution to minimize noise susceptibility. The content of this note is to propose some primary guidelines that must be followed by each subsystem. These guidelines will be submitted to the Technical Inspection and Safety Commission (TIS)

Evaluation of a commercial AdvancedTCA board management controller solution (IPMC)

The MicroTCA (MTCA) and AdvancedTCA (ATCA) industry standards have been selected as the hardware platform for the upgrade of the electronic systems of some of the experiments at the Large Hadron Collider (LHC) . In this context, the electronics support group for experiments at CERN is running a project to perform technical evaluations of MTCA and ATCA equipment. As part of this activity, a commercial solution for an Intelligent Platform Management Controller (IPMC), an essential component of any ATCA blade design, is being evaluated. We validated the supported IPMC features, checked the interoperability and adapted the reference design for use on an existing ATCA carrier board

To be or not to be overconnected; from individual difficulties to individual and collective coping mechanisms.

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MicroTCA and AdvancedTCA equipment evaluation and developments for LHC experiments

The MicroTCA (MTCA) and AdvancedTCA (ATCA) industry standards have been selected as the platform for many of the current and planned upgrades of the off-detector electronic systems of two of the LHC experiments at CERN. We present a status update from an ongoing project to evaluate commercial MTCA and ATCA components with particular emphasis on infrastructure equipment such as shelves and power-supplies. Shelves customized for use in the existing LHC rack infrastructure have been tested, and electrical and cooling measurements and simulations were performed. In-house developments for hardware platform management will also be shown

Design of an AdvancedTCA board management controller (IPMC)

The AdvancedTCA (ATCA) standard has been selected as the hardware platform for the upgrade of the back-end electronics of the CMS and ATLAS experiments of the Large Hadron Collider (LHC) . In this context, the electronic systems for experiments group at CERN is running a project to evaluate, specify, design and support xTCA equipment. As part of this project, an Intelligent Platform Management Controller (IPMC) for ATCA blades, based on a commercial solution, has been designed to be used on existing and future ATCA blades. This paper reports on the status of this project presenting the hardware and software developments

MicroTCA and AdvancedTCA equipment evaluation and customization for LHC experiments

The MicroTCA and AdvancedTCA industry standards are candidate modular electronics platforms for the upgrade of the current generation of high energy physics experiments at CERN. The PH-ESE group at CERN launched an xTCA evaluation project with the aim of performing technical evaluations and providing support for commercially available components. Over the past years, different equipment from different vendors has been acquired and evaluated. This paper summarizes our evaluation results of commercial MicroTCA and AdvancedTCA equipment. Special emphasis is put on the component requirements to be defined in view of future equipment procurement. Customized prototypes developed according to these generic specifications are presented for the first time