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An EAST Articulated Maintenance Arm (EAMA), upgraded based on an articulated inspection arm (AIA), which was successfully operated in Tore Supra in 2008, was developed for the purpose of the inspection and maintenance of damaged internal components during plasma discharges without breaking the East Advanced Superconducting Tokamak (EAST) ultra-high vacuum condition. However, the coupling structure and high redundancy of the EAMA, due to the requirement of coverage ratio and the limitation of the EAST environment, produces a limited accuracy in positioning control. Therefore, the optimal design of the geometric parameters plays a vital role in the EAMA’s performance. In this paper, the main characteristics of the EAMA system are investigated to formulate the optimization into a multi-objective problem. Furthermore, an approach based on the Monte Carlo method, integrated with a dedicated collision detection algorithm in the EAST environment, is elaborated on, which is utilized to calculate the collision-free workspace of the EAMA. With the knowledge of the workspace, the coverage ratio is obtained by a progressive meshing technique. Finally, several groups of geometric parameters are sampled to calculate the corresponding value of the objective functions, and the optimized combination of the geometric parameters is obtained by comparing the results.

The opportunistic infection oropharyngeal candidiasis (OPC; oral thrush) is a common oral infection among the immunocompromised. The oral cavity is a major entry portal to the body and oral health impacts several aspects of host immunity. While much is now known about microbiome dependent Th17 induction and protection against intestinal candidiasis and other Th17 driven responses, our understanding of the role of the microbiome in oral Th17 induction and oral antifungal immunity is rather rudimentary. We demonstrate a direct role for the microbiome in triggering protection against OPC. While wildtype (WT) mice raised under specific pathogen free (SPF) conditions are resistant to OPC, WT germ free (GF) mice succumbed to infection. Reconstitution of WT-GF mice with segmented filamentous bacteria (SFB) was sufficient to restore protection against OPC with associated increase in Th17 cells, neutrophils, and antimicrobial responses in the oral mucosa. Thus, SFB mono-colonization in WT-GF mice triggers oral mucosal Th17 induction to protect against oral thrush and reveals a role of the microbiome in promoting oral mucosal immunity. Supported by R37-DE022550

Additional file of The venom composition of the parasitic wasp Chelonus inanitus resolved by combined expressed sequence tags analysis and proteomic approach

The ITER Ion Cyclotron Resonance Heating (ICRH) system is designed to couple to the plasma 20 MW of RF power from two antennas in the 40-55 MHz frequency range during long pulses of up to 3600 s and under various plasma conditions with Edge Localized Modes. Radio-Frequency (RF) contacts are integrated within the ITER ICRH launcher in order to ensure the RF current continuity and ease the mechanical assembly by allowing the free thermal expansion of the Removable Vacuum Transmission Line coaxial conductors during RF operations or during 250{\textdegree}C baking phases. A material study has been carried out to determine which materials and associated coatings are relevant for RF contacts application in ITER. In parallel, RF tests have been performed with a new prototype of Multi-Contact (r) LA-CUT/0,25/0 contacts made of silver-coated CuCrZr louvers. During these tests on a RF vacuum resonator, currents between 1.2 kA and 1.3 kA peak have been reached a few tens of times in steady-state conditions without any visible damage on the louvers. A final 62MHz pulse ending in a 300s flat top at 1.9kA resulted in severe damage to the contact. In addition, a test bed which performs sliding test cycles has been built in order to reproduce the wear of the contact prototype after 30 000 sliding cycles on a 3 mm stroke at 175{\textdegree}C under vacuum. The silver coating of the louvers is removed after approximately a hundred cycles whilst, to the contrary, damage to the CuCrZr louvers is relatively low., Fusion Engineering and Design, Elsevier, A Para{\^i}tre

Fusion Tokamaks are complex machines which require special conditions for their operation, in particular, high vacuum inside the vessel and high temperature of the vessel walls. During plasma phases, the first wall components are highly stressed and a control is necessary in case of doubt about their condition. To be able to make safely such an inspection in a short period of time is a great advantage. The Articulated Inspection Arm (AIA) developed by the CEA provides the capability for fast inspections of the first wall overall surface keeping the vacuum and temperature conditions of the vessel. The robot prototype was validated in Tore Supra in 2008. In the frame of a joint laboratory, CEA/IRFM and ASIPP have decided to upgrade the existing AIA prototype to use it routinely in the EAST and WEST tokamaks. The robot has followed an important upgrade program in 2013 and 2014. The document presents the various upgrades made on the mechanics, the sensors, the electronics, the control station and the integration adaptation for the operation on EAST. From the AIA experience, thoughts for future inspection robots are given.

EAST articulated maintenance arm (EAMA) system is being collaboratively developed by ASIPP and CEA-IRFM for the purpose of remote inspection and simple maintenance operations in EAST vacuum vessel during physical experiments without breaking the ultra-high vacuum condition. The EAMA system design is based on a similar articulated inspection arm robot successfully demonstrated in Tore Supra in 2008. In order to better meet EAST configurations and maintenance requirements, optimized mechanisms and dimensions are considered for EAMA robot as upgrades. Besides, the segmented arm is equipped with a 3-DOF wrist end effector and gripper for gripping operation as well as inspection. Some calculations and simulations on statics, kinematics and workspace of EAMA have been presented to validate the feasibility. This paper introduces the overall design of the EAMA robot and presents implementation progress.

An articulated inspection arm (AIA) has been developed by CEA for visual inspection between pulses inside the Tore Supra tokamak vacuum vessel without breaking temperature and vacuum conditions. The eight meters length robot is composed of a shuttle and six articulated segments with a video camera at its end. A demonstration prototype has been achieved in 2008 at Tore Supra (Gargiulo, 2007; Houry, 2008; Perrot, 2003). A project to upgrade the AIA into a fully operational robot has been undertaken by IRFM and ASIPP in an Associated Laboratory. It will be in operation first in the EAST machine and afterwards in Tore Supra in its WEST (W/Tungsten Environment in Steady-state Tokamak) configuration where it is of paramount importance to survey possible degradation of W component surface. The control system of the robot has been extensively upgraded. The effort has been focused on three areas: (1) improvement of the arm position accuracy, (2) increase of the operational robustness, (3) use of a powerful graphical user interface including simulation of trajectories and robot deployment capabilities in a 3D viewer environment. The aim of this paper is to detail the architecture of the AIA control system.

Fusion machine operation requires high-vacuum conditions and does not tolerate water or gas leak in the vacuum vessels, even if they are micrometric. Tore Supra, as a fully actively cooled tokamak, has got a large leak management experience; 34 water leaks occurred since the beginning of its operation in 1988. To handle this issue, after preliminary machine protection phases, the current process for leak localization is based on water or helium pressurization network by network. It generally allows the identification of a set of components where the leakage element is located. However, the unique background of CEA-IRFM laboratory points needs of accuracy and promptness out in the leak localization process. Moreover, in-vessel interventions have to be performed trying to minimize time and risks for the persons. They are linked to access conditions, radioactivity, tracer gas high pressure and vessel conditioning. Remote operation will be one of the ways to improve these points on future fusion machines. In this case, leak sensors would have to be light weight devices in order to be integrated on a carrier or to be located outside with a sniffing process set up. A leak localization program is on-going at CEA-IRFM Laboratory with the first goal of identifying and characterizing relevant concepts to localize helium or water leaks on ITER. In the same time, CEA has developed robotic carrier for effective in-vessel intervention in a hostile environment. Three major tests campaigns with the goal to identify leak sensors have been achieved on several CEA test-beds since 2010. Very promising results have been obtained: relevant scenario of leak localization performed, concepts tested in a high volume test-bed called TITAN, and, in several conditions of pressure and temperature (ultrahigh vacuum to atmospheric pressure and 20–120 °C), “ppm” traces of helium or water have been measured. To improve these first promising results, a new test-bed called ROVE (remote operation vacuum equipment) has been set up in 2012 to qualify leak sensors and remote operation. A list of concepts has been set out from contacts with manufacturers and laboratories. For sniffing solutions it includes laser absorption measurement, mass spectrometer analyses and vibrating quartz. For embeddable concepts thermal conductivity and capacitive sensors are considered. Choice of concepts to detect water or helium traces is based on major criteria, such as weight, high sensibility and fast response time and recovery time. They also have to be operational under primary vacuum conditions or atmospheric pressure and from ambient temperature to 60 °C.

ITER will greatly rely on remote-handling operations to accomplish its scientific missions. Robotic systems will also be required to operate inside vacuum vessels in order to limit or replace human access, to intervene quickly between experimental sessions for in-vessel inspections and measurements, and to preserve the machine conditioning and thus improve machine availability. In this prospect, a multipurpose carrier prototype called Articulated Inspection Arm (AIA) was developed by CEA laboratories within the European work program. With an embedded camera, it successfully demonstrated close inspection feasibility inside Tore Supra tokamak. The AIA robot was designed for mini-invasive operations with interchangeable diagnostics to be plugged at its head. This covers various applications for the safety, the operation and the scientific mission (in-vessel inspection, plasma diagnostics calibrations or inner components analysis and treatments). This paper presents recent analysis and results obtain with diagnostics developed by CEA for in-vessel remote-handling intervention.

A multipurpose carrier prototype called Articulated Inspection Arm (AIA) has been developed and demonstrated by CEA laboratories to operate embedded diagnostics or tools into a tokamak vacuum-vessel. The AIA robot with a vision diagnostic has been deployed inside the vacuum-vessel of Tore Supra tokamak and has realized closed inspections of plasma facing components’ under relevant conditions (high vacuum and temperature). CEA is engaged in development of interchangeable diagnostics or tools to be plugged on the front head of the arm. This covers applications such as in-vessel inspections, water leak localization, Plasma Facing Components (PFCs) characterization and treatment. This paper describes R&D activities performed in CEA laboratories to develop diagnostics and tools for in-vessel interventions. The AIA multipurpose carrier to carry such devices is also presented. The first demonstration of a quick intervention for plasma facing components performed in the Tore Supra Facility is described as well.

Robotic operations are one of the major maintenance challenges for ITER and future fusion reactors. CEA has developed a multipurpose carrier able to realize deployments in the plasma vessel without breaking the Ultra High Vacuum (UHV) and temperature conditioning. A 6 years RD its geometry allows a complete close inspection of Plasma Facing Components (PFCs) of the Tore Supra vessel. Different tools are being developed by CEA to be plugged at the front head of the carrier. The diagnostic presently in operation consists in a viewing system offering accurate visual inspection of PFCs. Leak detection of first wall based on helium sniffing and laser compact system for carbon co-deposited layers characterizations or treatments are also considered for demonstration. In April 2008, the AIA robot equipped with its vision diagnostic has realized a complete deployment into Tore Supra and the first closed inspection of the vessel under UHV conditions. During the upcoming experimental campaign, the same operation will be performed under relevant conditions (10 −6 Pa and 120 °C) after a conditioning phase at 200 °C to avoid outgassing pollution of the chamber. This paper describes the different steps of the project development, robot capabilities with the present operations conducted on Tore Supra and future requirements for making the robot a tool for tokamak routine operation.

Robotic operations are one of the major maintenance challenges for ITER and future fusion reactors. In particular, in-vessel inspection operations without loss of conditioning will be mandatory. In this context, an Articulated Inspection Arm (AIA) is currently developed by the CEA within the European work programme framework, which aims at demonstrating the feasibility of a multi-purpose in-vessel Remote Handling inspection system using a long reach, limited payload carrier (up to 10 kg). It is composed of 5 segments with 8 degrees of freedom and a total range of 8 m. The first in situ tests will take place by the end of 2007 on the Tore Supra Tokamak at Cadarache (France). They will validate concepts for operations under ITER relevant vacuum and temperature conditions. After qualification, the arm will constitute a promising tool for various applications. Several processes are already considered for ITER maintenance and will be demonstrated on the AIA robot carrier: • The first embedded process is the viewing system. It is already manufactured and will allow close visual inspection of the complex Plasma Facing Components (PFC) (limiters, neutralisers, RF antenna, diagnostic windows, etc.). • In situ localisation of water leakage based on a helium sniffing system is also being studied to improve and facilitate maintenance operations. • Finally a laser ablation system for PFC detritiation, developed in CEA laboratories, is being fitted to be implemented on the robot for future operation in Tore Supra. This paper deals with the integration of the robot into Tore Supra and the progress in the development of the processes listed above. It also describes the current test campaign aiming to qualify the robot performance and reliability under vacuum and temperature conditions.

The SEC14 gene encodes a phosphatidylinositol/phosphatidylcholine transfer protein essential for secretion and growth in yeast (1). Mutations (cki1, cct1, and cpt1) in the CDP-choline pathway for phosphatidylcholine synthesis suppress the sec14 growth defect (2), permitting sec14(ts) cki1, sec14(ts) cct1, and sec14(ts) cpt1 strains to grow at the sec14(ts) restrictive temperature. Previously, we reported that these double mutant strains also excrete the phospholipid metabolites, choline and inositol (3). We now report that these choline and inositol excretion phenotypes are eliminated when the SPO14 (PLD1) gene encoding phospholipase D1 is deleted. In contrast to sec14(ts) cki1 strains, sec14(ts) cki1 pld1 strains are not viable at the sec14(ts) restrictive temperature and exhibit a pattern of invertase secretion comparable with sec14(ts) strains. Thus, the PLD1 gene product appears to play an essential role in the suppression of the sec14(ts) defect by CDP-choline pathway mutations, indicating a role for phospholipase D1 in growth and secretion. Furthermore, sec14(ts) strains exhibit elevated Ca2+-independent, phophatidylinositol 4,5-bisphosphate-stimulated phospholipase D activity. We also propose that phospholipase D1-mediated phosphatidylcholine turnover generates a signal that activates transcription of INO1, the structural gene for inositol 1-phosphate synthase.

International audience; Proteases regulate numerous physiological functions in all living organisms. Because of their contribution to βAPP processing, α-, β- and γ-secretases have focused particular attention of researchers in the field of Alzheimer's disease (AD) during the past 20 years. Whereas the β-secretase BACE1 and the heterotetrameric presenilin-dependent γ- secretase complex were identified between 1995 and 2002, α-secretase activity was attributed to previously described ADAM10 and ADAM17, two members of the type I integral membrane protein family called ADAMs (A Disintegrin And Metalloprotease). ADAM10 and/or ADAM17 target numerous substrates through various modes of action. This review focuses on the complex physiology of these α-secretases and will document their contribution to cancers, diabetes, rheumatoid arthritis, and prion diseases besides their well characterized role in Alzheimer's disease.

Recent estimates of the welfare cost of consumption volatility find that it is significant in developing nations, where it may reach an equivalent of reducing consumption by 10 percent per year. Hence, examining the determinants of consumption volatility is of utmost relevance. Based on cross-country data for the period 1960-2005, the paper explains consumption volatility using three sets of variables: one refers to the volatility of income and the persistence of income shocks; the second set of variables refers to policy volatility, considering the volatility of public spending and the size of government; while the third set captures the ability of agents to smooth shocks, and includes the depth of the domestic financial markets as well as the degree of integration to international capital markets. To allow for potential endogenous regressors, in particular the volatility of fiscal policy and the size of government, the system is estimated using the instrumental variables method. The results indicate that, besides income volatility, the variables with the largest and most robust impact on consumption volatility are government size and the volatility of public spending. Results also show that deeper and more stable domestic financial markets reduce the volatility of consumption, and that more integrated financial markets to the international capital markets are associated with lower volatility of consumption.

In yeast, mutations in the CDP-choline pathway for phosphatidylcholine biosynthesis permit the cell to grow even when the SEC14 gene is completely deleted (Cleves, A., McGee, T., Whitters, E., Champion, K., Aitken, J., Dowhan, W., Goebl, M., and Bankaitis, V. (1991) Cell 64, 789-800). We report that strains carrying mutations in the CDP-choline pathway, such as cki1, exhibit a choline excretion phenotype due to production of choline during normal turnover of phosphatidylcholine. Cells carrying cki1 in combination with sec14(ts), a temperature-sensitive allele in the gene encoding the phosphatidylinositol/phosphatidylcholine transporter, have a dramatically increased choline excretion phenotype when grown at the sec14(ts)-restrictive temperature. We show that the increased choline excretion in sec14(ts) cki1 cells is due to increased turnover of phosphatidylcholine via a mechanism consistent with phospholipase D-mediated turnover. We propose that the elevated rate of phosphatidylcholine turnover in sec14(ts) cki1 cells provides the metabolic condition that permits the secretory pathway to function when Sec14p is inactivated. As phosphatidylcholine turnover increases in sec14(ts) cki1 cells shifted to the restrictive temperature, the INO1 gene (encoding inositol-1-phosphate synthase) is also derepressed, leading to an inositol excretion phenotype (Opi-). Misregulation of the INO1 gene has been observed in many strains with altered phospholipid metabolism, and the relationship between phosphatidylcholine turnover and regulation of INO1 and other co-regulated genes of phospholipid biosynthesis is discussed.

Authors’ original file for figure 1

Authors’ original file for figure 1