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About one hundred magnets of six different types shall be installed in the High Luminosity LHC (HL-LHC) in the years 2026-2028 at CERN. The magnets design, construction and test are based on CERN collaborations with institutes and industrial partners in USA, Spain, Italy, Japan and China. Three types of correctors are based on Nb‒Ti technology and feature conductor peak fields in the 2 to 4 T range: for all of them the prototype phase has been successfully completed. The production is well advanced for the superferric correctors, and is starting for the canted cosine theta correctors and for the nested correctors. The separation and recombination Nb‒Ti dipoles D1 and D2, with a 4.5-6 T bore field range, are both in the prototype phase after the completion of the short model program. The most challenging magnet, the Nb3Sn quadrupole with conductor peak field above 11 T, is in the prototype phase at CERN and halfway through the production phase in the USA. In this paper we will give, for each type of magnet, an overview of the main achievements obtained so far and we will outline the technical points still needing validation from the prototype program.

International audience; For the HL-LHC project, a 90 mm NbTi cos(2θ) double aperture quadrupole magnet with an operating gradient of 120 T/m at 1.9 K has been designed as an option to replace the 70 mm aperture LHC quadrupole MQY. CEA in collaboration with CERN designed and manufactured a single aperture short model magnet with a magnetic length of 1.215 m at 1.9 K called MQYYM. The MQYYM cold test occurred at CEA at 4.2 K in a vertical cryogenic station. During the power test, the operating gradient at 1.9 K has been reached after two training quenches. All along the test, magnetic and mechanical measurements were done using respectively a rotating probe and strain gauges. This paper describes the performance of the MQYYM at 4.2 K and gives an analysis of the data acquired during the test, including training behavior, quench detection, protection and field quality measurements.

The use of pressurized bladders for stress control of superconducting magnets was firstly proposed at Lawrence Berkeley National Laboratory in the early 2000s. Since then, the so-called ‘bladders and keys’ procedure has become one of the reference techniques for the assembly of high-field accelerator magnets and demonstrators. Exploiting the advantages of this method is today of critical importance for Nb$_{3}$Sn-based accelerator magnets, whose production requires the preservation of tight stress targets in the superconducting coils to limit the effects of the strain sensitivity and brittleness of the conductor. The present manuscript reports on the results of an experimental campaign focused on the optimization of the ‘bladders and keys’ assembly process in the MQXFB quadrupoles. These 7.2 m long magnets shall be among the first Nb$_{3}$Sn cryomagnets to be installed in a particle accelerator as a part of the High Luminosity upgrade of the LHC. One of the main practical implications of the bladders technique, especially important when applied to long magnets like MQXFB, is that to insert the loading keys, the opening of a certain clearance in the support structure is required. The procedure used so far for MQXF magnets involved an overstress in the coils during bladder inflation. The work presented here shows that such an overshoot can be eliminated thanks to additional bladders properly positioned in the structure. This optimized method was validated in a short model magnet and in a full-length mechanical model, becoming the new baseline for the series production at CERN Furthermore, the results are supported by numerical predictions using finite element models. The use of pressurized bladders for stress control of superconducting magnets was firstly proposed at Lawrence Berkeley National Laboratory (LBNL) in the early 2000s. Since then, the so-called “bladders and keys” procedure has become one of the reference techniques for the assembly of high-feld accelerator magnets and demonstrators. Exploiting the advantages of this method is today of critical importance for Nb3Sn-based accelerator magnets, whose production requires the preservation of tight stress targets in the superconducting coils to limit the effects of the strain sensitivity and brittleness of the conductor. The present manuscript reports on the results of an experimental campaign focused on the optimization of the “bladders and keys” assembly process in the MQXFB quadrupoles. These 7.2 m long magnets shall be among the frst Nb3Sn cryomagnets to be installed in a particle accelerator as a part of the High Luminosity upgrade of the LHC. One of the main practical implications of the bladders technique, especially important when applied to long magnets like MQXFB, is that to insert the loading keys, the opening of a certain clearance in the support structure is required. The procedure used so far for MQXF magnets involved an overstress in the coils during bladder infation. The work presented here shows that such an overshoot can be eliminated thanks to additional bladders properly positioned in the structure. This optimized method was validated in a short model magnet and in a full-length mechanical model, becoming the new baseline for the series production at CERN. Furthermore, the results are supported by numerical predictions using Finite Element models. The use of pressurized bladders for stress control of superconducting magnets was firstly proposed at Lawrence Berkeley National Laboratory (LBNL) in the early 2000s. Since then, the so-called bladders and keys procedure has become one of the reference techniques for the assembly of high-field accelerator magnets and demonstrators. Exploiting the advantages of this method is today of critical importance for Nb3Sn-based accelerator magnets, whose production requires the preservation of tight stress targets in the superconducting coils to limit the effects of the strain sensitivity and brittleness of the conductor. The present manuscript reports on the results of an experimental campaign focused on the optimization of the bladders and keys assembly process in the MQXFB quadrupoles. These 7.2 m long magnets shall be among the first Nb3Sn cryomagnets to be installed in a particle accelerator as a part of the High Luminosity upgrade of the LHC. One of the main practical implications of the bladders technique, especially important when applied to long magnets like MQXFB, is that to insert the loading keys, the opening of a certain clearance in the support structure is required. The procedure used so far for MQXF magnets involved an overstress in the coils during bladder inflation. The work presented here shows that such an overshoot can be eliminated thanks to additional bladders properly positioned in the structure. This optimized method was validated in a short model magnet and in a full-length mechanical model, becoming the new baseline for the series production at CERN. Furthermore, the results are supported by numerical predictions using Finite Element models.

International audience; In the framework of the HL-LHC project, a NbTi double aperture quadrupole magnet MQYY is being developed as an option to replace the LHC magnet MQY. This 90 mm double aperture cos-2θ quadrupole has an operating gradient of 120 T/m at 1.9 K. To demonstrate the validity of the design, a single aperture short model of 1.2 m called MQYYM has been developed. Designed by CEA and manufactured in collaboration with CERN, the MQYYM magnet is being prepared for cold test at CEA in a dedicated cryogenic station with LHe bath at 1 bar 4.2 K and 23 mbar 1.9 K. First, this paper will summarize the initial and as-built magnet designs based on the assembly at CERN. Second, updated mechanical measurements of collaring and axial pre-loading will be presented. Finally warm magnetic measurements performed at CERN during the assembly and at CEA during test preparation will be detailed.

MQXF is the Nb 3 Sn Low-β quadrupole magnet that the HL-LHC project is planning to install in the LHC interaction regions in 2026 to increase the LHC integrated luminosity. The magnet will be fabricated in two different lengths: 4.2 m for MQXFA, built in the US by the Accelerator Upgrade Project (AUP), and 7.15 m for MQXFB, fabricated by CERN. In order to qualify the magnet design and characterize its performance with different conductors, cable geometries and pre-load configurations, five short model magnets, called MQXFS, were fabricated, assembled and tested. We compare the mechanical behavior of short model magnets using experimental data and new numerical models that take into account the measured coil sizes as a function of position. -MQXF is the Nb3Sn Low-β quadrupole magnet that the HL-LHC project is planning to install in the LHC interaction regions in 2026 to increase the LHC integrated luminosity. The magnet will be fabricated in two different lengths: 4.2 m for MQXFA, built in the US by the Accelerator Upgrade Project (AUP), and 7.15 m for MQXFB, fabricated by CERN. In order to qualify the magnet design and characterize its performance with different conductors, cable geometries and pre-load configurations, five short model magnets, called MQXFS, were fabricated, assembled and tested. We compare the mechanical behavior of short model magnets using experimental data and new numerical models that take into account the measured coil sizes as a function of position.

Lymphoceles are lymphatic fluid collections resulting from lymphatic vessel disruption after surgery or trauma. They are most often described following retroperitoneal surgeries such as cystectomies, prostatectomies, renal transplants, and gynecologic surgeries. Most lymphoceles are asymptomatic and resolve spontaneously without treatment. If persistent, they can become infected or exert mass effect on adjacent structures causing pain, urinary, or lower limb edema particularly for lymphoceles in the pelvis Symptomatic lymphoceles should be treated to relieve symptoms and prevent functional compromise of vital adjacent structures. Although surgery has been traditionally accepted as the gold standard treatment, advances in imaging and interventional technology allow for less invasive, percutaneous treatment. Available minimally invasive treatment options include percutaneous aspiration, catheter drainage, sclerotherapy, and lymphangiography with lymphatic embolization. A review of these treatment options and a suggested algorithm for managing lymphoceles is presented.

For the upgrade of the LHC during the long shutdown 2 and for the HL-LHC upgrade during the long shutdown 3, a few 15 m 8.3 T Nb–Ti main dipole magnets are foreseen to be replaced by two 11 T Nb3Sn dipoles, 5.5 m long each. After the production and test of three single aperture models at CERN, the first 2-m-long twin-aperture model has been tested. The model was used to exploit the limits of the model in terms of quench performance and protection. The protection studies included the heater efficiency studies and hotspot temperature studies. In this paper, the performance of the magnet DP101 in terms of training behavior, detection, and protection, and other cold powering test will be presented and discussed.

Background Coronary heart disease is the leading cause of death in the world. Nowadays, there are still patients with untreatable coronary obstructions and exercise therapy could be an option to improve their quality of life and probably diminish mortality. Cardiac rehabilitation programs are recommended worldwide due its effectiveness and safety. However very high risk patients are often not included. Purpose To evaluate the benefit and safety of exercise therapy as a part of a cardiac rehabilitation program in patients with untreatable severe coronary heart disease. Methods A cohort of patients with coronary heart disease included in a cardiac rehabilitation program were studied. Those with severe coronary heart disease (Syntax score ≥33, group A) were identified. Patients were stratified using clinical records and cardiopulmonary exercise testing. They trained for 30 minutes, five times a week of aerobic exercise (cycle ergometer) and this therapy was complemented with general strength, coordination, balance and flexibility maneuvers. After twenty exercise sessions, a second cardiopulmonary exercise test was performed. Symptom limited cardiopulmonary exercise testing was undertaken using a ramp Balke protocol and cardiopulmonary variables were recorded. These patients were compared with their counterparts without severe coronary heart disease (Control group, group B). Studied variables were presented as frequencies (%), mean (SD), median (range) as appropriate. Comparisons between groups were made using chi square or paired T test as needed. All p values Results From a total of 546 patients, seventy-one had severe coronary heart disease (Syntax score ≥33). There were no significant differences between groups on change of METs value and number of sessions assisted. No major adverse cardiovascular outcome was observed. The percentage of exercise induced arrhythmias was 75% in very high risk group vs 76% in control group, (p>0.05). Results are shown in table 1. Table 1. Characteristics between groups Patients Group A (n=75) Group B (n=471) p value Assisted training sessions 15±7 14±6 ns Increment in MET (ml/kg/min) 1.32±1.34 1.35±1.56 ns Arrhythmias, n (%) 56 (75) 370 (76) ns Angor/ST depression, n (%) 11 (15) 15 (3) Conclusion Exercise training could be performed in an effective and safe manner in patients with very high risk untreated coronary heart disease.

To improve the technology of the new generation of accelerator magnets, prototypes are being manufactured and tested in several laboratories. In parallel, many numerical analyses are being carried out to predict the magnets behaviour and interpret the experimental results. This paper focuses on the quench propagation velocity, which is a crucial parameter as regards the energy dissipation along the magnet conductor. The THELMA code, originally developed for cable-in-conduit conductors for fusion magnets, has been used to study such quench propagation. To this purpose, new code modules have been added to describe the Rutherford cable geometry, the material non-linear thermal properties and to describe the thermal conduction problem in transient regime. THELMA can describe the Rutherford cable at the strand level, modelling both the electrical and thermal contact resistances between strands and enabling the analysis of the effects of local hot spots and quench heaters. This paper describes the model application to a sample of Short Model Coil tested at CERN: a comparison is made between the experimental results and the model prediction, showing a good agreement. A comparison is also made with the prediction of the most common analytical models, which give large inaccuracies when dealing with low n -index cables like Nb 3 Sn cables.

The High Luminosity (HiLumi) Large Hadron Collider (LHC) project has, as the main objective, to increase the LHC peak luminosity by a factor five and the integrated luminosity by a factor ten. This goal will be achieved mainly with a new interaction region layout, which will allow a stronger focusing of the colliding beams. The target will be to reduce the beam size in the interaction points by a factor of two, which requires doubling the aperture of the low-β (or inner triplet) quadrupole magnets. The use of Nb3Sn superconducting material and, as a result, the possibility of operating at magnetic field levels in the windings higher than 11 T will limit the increase in length of these quadrupoles, called MQXF, to acceptable levels. After the initial design phase, where the key parameters were chosen and the magnet's conceptual design finalized, the MQXF project, a joint effort between the U.S. LHC Accelerator Research Program and the Conseil Europeen pour la Recherche Nucleaire (CERN), has now entered the construction and test phase of the short models. Concurrently, the preparation for the development of the full-length prototypes has been initiated. This paper will provide an overview of the project status, describing and reporting on the performance of the superconducting material, the lessons learnt during the fabrication of superconducting coils and support structure, and the fine tuning of the magnet design in view of the start of the prototyping phase.

For the upgrade of the LHC in LS2 and for the High Luminosity upgrade in LS3, a few 15-m Nb–Ti main dipole magnets are foreseen to be replaced by two 5.5-m-long Nb3Sn dipoles each. After a series of dipole models produced and tested by the collaborating partners at FNAL, in 2014 and 2015, the first short dipole model magnets have been produced and tested at CERN in a single aperture configuration. In this paper, the test results and test analyses will be discussed with a focus on training and cold powering performance.

In the framework of the European project EuCARD, the High Field Magnet project, led by a CERN-CEA collaboration, implied the development of a large aperture Nb3Sn dipole magnet called FRESCA2. The magnet uses four double-pancake block-type coils, each about 1.5 m long. In order to characterize strand and cable properties, as well as to qualify the coil fabrication process, CERN started in 2012 the design and fabrication of the Racetrack Model Coil (RMC) magnet, a short model magnet using the same cable as FRESCA2 magnet with only two flat double-pancake coils about 0.8 m long. In 2013, two superconducting coils have been fabricated, making use of two different types of superconductor. In 2014 and 2015, the coils were tested both in a single and in a double-coil configuration in a support structure based on an external aluminum shell pre-loaded with water-pressurized bladders. In this paper, we describe the design of the RMC magnet and its coils, provide the main parameters of the superconductor, and report the results of three powering tests, focusing on quench performance, training, and quench locations.

© 2016 IEEE. Protection heaters are essential elements of a quench protection scheme for high-field accelerator magnets. Various heater designs fabricated by LARP and CERN have been already tested in the LARP high-field quadrupole HQ and presently being built into the coils of the high-field quadrupole MQXF. In order to compare the heat flow characteristics and thermal diffusion timescales of different heater designs, we powered heaters of two different geometries in ambient conditions and imaged the resulting thermal distributions using a high-sensitivity thermal video camera. We observed a peculiar spatial periodicity in the temperature distribution maps potentially linked to the structure of the underlying cable. Two-dimensional numerical simulation of heat diffusion and spatial heat distribution have been conducted, and the results of simulation and experiment have been compared. Imaging revealed hot spots due to a current concentration around high curvature points of heater strip of varying cross sections and visualized thermal effects of various interlayer structural defects. Thermal imaging can become a future quality control tool for the MQXF coil heaters.

The luminosity upgrade of the Large Hadron Collider (HL-LHC) requires the development of a new generation of superconducting magnets based on Nb$_{3}$Sn technology. In order to monitor the magnet thermo-mechanical behaviour during its service life, from the coil fabrication to the magnet operation, reliable sensing systems need to be implemented. In the framework of the FP7 European project EUCARD, Nb$_{3}$Sn racetrack coils are developed as test beds for the fabrication validation, the cable characterization and the instrumentation development. Fiber optic sensors (FOS) based on Fiber Bragg Grating (FBG) technology have been embedded in the coils of the Short Model Coil (SMC) magnet. The FBG sensitivity to both temperature and strain required the development of a solution able to separate the mechanical and temperature effects. This work presents the feasibility study of the implementation of embedded FBG sensors for the temperature and strain monitoring of the 11 T type conductor. We aim to monitor and register these effects during the coil fabrication and cool down in a standalone configuration.

Within the scope of the High-Luminosity LHC project, the collaboration between CERN and U.S. LARP is developing new low- $\beta$ quadrupoles using the Nb3Sn superconducting technology for the upgrade of the LHC interaction regions. The magnet support structure of the first short model was designed, and two units were fabricated and tested at CERN and at LBNL. The structure provides the preload to the collar–coil subassembly by an arrangement of outer aluminum shells pretensioned with water-pressurized bladders. For the mechanical qualification of the structure and the assembly procedure, superconducting coils were replaced with solid aluminum “dummy coils,” and the structure was preloaded at room temperature and then cooled-down to 77 K. The mechanical behavior of the magnet structure was monitored with the use of strain gauges installed on the aluminum shells, the dummy coils, and the axial preload system. This paper reports on the outcome of the assembly and the cooldown tests with dummy coils, which were performed at CERN and at LBNL, and presents the strain gauge measurements compared with the 3-D finite-element model predictions.

In the frame of the high-luminosity upgrade project (HL-LHC) at CERN, a double aperture, independently powered, family of beam orbit corrector magnets will be installed close to the two main LHC experiments Atlas and CMS. These 2.6 T magnets, built using a canted cos-theta design. This paper describes the development of the prototype, full size 2-m-long magnets. We first focus on design and assembly techniques: from coil winding using a CNC machined aluminium former to impregnation, layer-jump, quench protection, and yoke assembly. We then present the power test results at 1.9 K: training, field quality and protection.

FRESCA2 is a dipole magnet dedicated to upgrade the present CERN cable test station FRESCA to a nominal bore field of 13 Tesla (T) in a 100 mm clear aperture. This paper reports on the assembly process and the three cool-down tests to cryogenic temperature of the support structure of FRESCA2. This structure is based on an aluminum alloy shrinking cylinder pre-loaded through the use of water-pressurized bladders. To verify the assembly and loading processes, this structure was assembled using full block aluminum alloy “dummy coils” standing for the Nb 3 Sn coils. Then, the whole assembled structure was cooled-down to 77 K with liquid nitrogen in a dedicated facility at CERN. The mechanical behavior was monitored at all stages by strain gauges located on different components of the structure. Three cryogenic tests were made by increasing the loading gradually up to values corresponding to the ultimate field of 15 T. The expected stresses within the structure after assembly, loading and cool-down were determined from the 3-D finite-element model of the support structure. A comparison of the model predictions with the strain gauge data is presented.

New low-β quadrupole magnets are being developed within the scope of the High Luminosity LHC (HL-LHC) project in collaboration with the US LARP program. The aim of the HLLHC project is to study and implement machine upgrades necessary for increasing the luminosity of the LHC. The new quadrupoles, which are based on the Nb₃Sn superconducting technology, will be installed in the LHC Interaction Regions and will have to generate a gradient of 140 T/m in a coil aperture of 150 mm. In this paper, we describe the design of the short model magnet support structure and discuss results of the detailed 3D numerical analysis performed in preparation for the first short model test.

The luminosity upgrade of the large hadron collider (HL-LHC) requires the development of new type of superconducting cables based on advanced Nb 3 Sn strands. In the framework of the FP7 European project EUCARD, the cables foreseen for the HL-LHC project have been tested recently in a simplified racetrack coil configuration, the so-called Short Model Coil (SMC). In 2013-2014, two SMCs wound with 40-strand (RRP 108/127) cables, with different heat treatment processes, reached during training at 1.9 K a current and peak magnetic field of 15.9 kA, 13.9 T, and 14.3 kA, 12.7 T, respectively. Using the measured signals from the voltage taps, the behavior of the quenches is analyzed in terms of transverse and longitudinal propagation velocity and hot-spot temperature. These measurements are compared with both analytical and numerical calculations from adiabatic models. The coherence of the results from the presented independent methods helps in estimating the relevance of the material properties and the adiabatic assumption for impregnated Nb 3 Sn conductor modeling.

The short model coil (SMC) dipole magnet has been designed and constructed in the framework of the European project EuCARD as a test bed for Nb 3 Sn magnet R&D in terms of coil fabrication technology and testing of Rutherford-type cables. Two pairs of racetrack coils were successfully tested in 2012, obtaining 12.5 T in the winding at 1.9 K, thus demonstrating SMC as a valid magnet design for conductor tests. These successful results prompted a new test campaign of SMC using the cable of the 11-T dipole project. The size of this cable is such that only one double pancake can be accommodated in the mechanical structure. During the latest tests using the 11-T cable, a new record field of 13.5 T was achieved, confirming the excellent capability of SMC to qualify a conductor, providing precise information of the stability and general cable performance, and to test insulation techniques, instrumentation systems, and coil fabrication processes. This paper describes the challenges of this new assembly, indicating novelties in the fabrication technology and reports on the measurements and the performance of SMC using CERN's 11-T-dipole-type conductor.

In exploration wells in shallow waters of Mexico, the challenge of reducing drilling time and enhancing efficiency of well construction had become a problem on a daily basis. The continued use and success of Casing while Drilling (CwD) led the operator and service companies to embark upon a more ambitious project. Using the learning curve of previous 20″ CwD conductor sections, the first 34″ PDC drillable drill bit was designed and the first Casing Running Tool (CRT) for 30″ casing was utilized. These tools were used to apply the technology in the conductor sections of wells targeting Mesozoic formations. A technical feasibility study was performed by the operator and service companies involved to analyze the viability of executing this whilst creating new products. This saw the implementation of CwD using 30″ casing, an integral drilling system using casing as the drill string and a PDC drillable bit that allows drilling and casing of the section to take place simultaneously and eliminates the need to assemble a 36″ drilling BHA and, subsequently run casing. Once the CwD BHA (Casing + Drillable drill bit) reaches the final depth of the section, the hole is already cased and ready to cement. This challenged the service companies' engineering departments to develop the custom made tools for the application. In the first well, the original plan was to drill the 30″ section using a 36″ roller cone bit, drilling from sea bed (+/-78m) to 250 mts. This was the candidate well that the operator chose to utilize an ″unconventional″ drilling system to ensure reaching TD in a single run prior to cementing the casing. The 30″ × 34″ conductor section was drilled and cased at a depth of 256 meters, drilling a total of 178 meters with the PDC drillable drill bit (4 blades + 19 mm cutters) in 9:52 hrs., with an average rate of penetration (ROP) of 18.04 m/hr., and then preparations for cementing the 30″casing began. This entire operation represented a 26.3% time reduction compared with a conventional drilling operation This document will show the methodology and technology used in Mexico Marine Exploratory fields to reduce and mitigate the risk of not setting the casing at TD, focusing on the pre-planning stage, proper bit selection, Torque & Drag (T&D) analysis, casing fatigue life analysis and the use of new technology with a high success ratio on the operations in order to add value and ensure the customer' satisfaction.

The next generation of LHC superconducting magnets is very challenging and must operate in harsh conditions: high radiation doses in a range between 10 and 50 MGy, high voltage environment of 1 to 5 kV during the quench, dynamic high magnetic field up to 12 T, dynamic temperature range 1.8 K to 300 K in 0.6 sec. For magnet performance and long term reliability it is important to study dynamic thermal effects, such as the heat flux through the magnet structure, or measuring hot spot in conductors during a magnet quench with high sampling rates above 200 Hz. Available on the market cryogenic temperature sensors comparison is given. An analytical model for special electrically insulating thermal anchor (Kapton pad) with high voltage insulation is described. A set of instrumentation is proposed for fast monitoring of thermal processes during normal operation, quenches and failure situations. This paper presents the technology applicable for mounting temperature sensors on high voltage superconducting (SC) cables. The temperature measurements of fast heat cross-propagation in MQXC SC cable and FCM dynamic tests are also presented. Novel thermometry has been successfully applied to a few CERN magnet prototypes (MQXC, FCM and FRESCA2).

Over the last five years, the model MQXC quadruple, a 120-mm aperture, 120 T/m, 1.8 m long, Nb-Ti version of the LHC insertion upgrade (due in 2021), has been developed at CERN. The magnet incorporates several novel concepts to extract high levels of heat flux and provide high quality field harmonics throughout the full operating current range. Existing LHC-dipole cable with new, open cable and ground insulation was used. Two, nominally identical 1.8-m-long magnets were built and tested at 1.8 K at the CERN SM18 test facility. This paper compares in detail the two magnet tests and presents: quench performance, internal stresses, heat extraction simulating radiation loading in the superconducting coils, and quench protection measurements. The first set of tests highlighted the conflict between high magnet cooling capability and quench protection. The second magnet had additional instrumentation to investigate further this phenomenon. Finally, we present test results from a new type of superconducting magnet protection system.

The key objective of the High Field Magnet work package of the European Project EuCARD is to design and fabricate the Nb3Sn dipole magnet FRESCA2. It has an aperture of 100 mm and a target bore field of 13 T. The design features four 1.5 m long double-layer coils wound with a 21 mm wide cable. The project has now entered its experimental phase in view of the magnet fabrication. We present the experimental test campaign conducted on cable samples in order to understand and to control better the cable behavior and geometry. One full scale double-layer coil using copper cable with the final dimensions and insulation scheme has been wound and heat treated in order to check the fabrication process. This has given useful feedback on the fabrication procedure and on the expected magnet dimensions, as well as on the tooling itself.

Leptin is a hormone that regulates energy balance. Since its discovery two decades ago, several efforts have been made to fully understand its role in metabolic regulation of feeding behavior, reproduction, glucose homeostasis, immune function, bone formation, lipid metabolism, among others. Its use as a therapeutic option in obese patients is still limited due to the syndrome known as Leptin resistance. In this study, we determined that the treatment of a soluble form of human Leptin (W100E) reduced food intake, body weight and triglycerides levels, but increased HDL-cholesterol levels on obese mice subjected to high-fat/high-fructose diet. In contrast, treatment with soluble human Leptin increased food intake but did not increase body weight and total-cholesterol in mice with normal diet. When stopping the treatment with human W100E-Leptin, it was detected a significant increase in body weight in all groups of mice apart from the control, indicating a rebound effect. The results contribute to the understanding of how to increase Leptin sensitivity and in consequence to overcome Leptin resistance syndrome. This might be relevant in offering more evidence of the potential use of the Leptin in the treatment against obesity and overweight conditions.

© 2015 IEEE. In preparation for the high-luminosity upgrade of the Large Hadron Collider (LHC), the LHC Accelerator Research Program (LARP) in collaboration with CERN is pursuing the development of MQXF: a 150-mm-aperture high-field Nb3Sn quadrupole magnet. The development phase starts with the fabrication and test of several short models (1.2-m magnetic length) and will continue with the development of several long prototypes. All of them are mechanically supported using a shell-based support structure, which has been extensively demonstrated on several RD models within LARP. The first short model MQXFS-AT has been assembled at LBNL with coils fabricated by LARP and CERN. In this paper, we summarize the assembly process and show how it relies strongly on experience acquired during the LARP 120-mm-aperture HQ magnet series. We present comparison between strain gauges data and finite-element model analysis. Finally, we present the implication of the MQXFS-AT experience on the design of the long prototype support structure.

The luminosity upgrade of the Large Hadron Collider (HL -LHC) planned at the European Organizat ion for Nuclear Research (CERN) requires the development of a new generation of superconducting magnets based on Nb 3 Sn technology. The instrumentation required fo r the racetrack coils needs the development of reliable sensing systems able to monitor the magnet thermo -mechanical behavior during its service life, from the coil fabrication to the magnet operation. With this purpose , Fiber Bragg Grating (FBG) sensors have been embedded in the coils of the Short Model Coil (SMC) magnet fabricated at CERN . The FBG sensitivity to both temperature and strain required the development of a solution able to separate mechanical and temperature effects. This work presents for th e first time a feasibility study devoted to the implementation of an embedded FBG sensor for the measurement of the "true " temperature in the impregnated Nb 3 Sn coil during t he fabrication process. Keywords: Fiber Optic sensors, Fiber Bragg gratings, superc onducting magnets , Nb

The low-beta triplets of the Large Hadron Collider were designed and constructed by a world-wide collaboration officially formed in 1998. Over the course of the following years the collaboration worked to produce the triplet components, including four 215 T/m, 70 mm aperture quadrupoles, a DFBX distribution feedbox, and at the low luminosity interaction points a cold D1 beam separation dipole. In 2005 the first triplet was installed in the LHC tunnel, and at the end of 2007 hardware commissioning of the first triplets started. As of August 2008 five triplets have been successfully powered. This paper documents the processes and experience gained during the commissioning phase of the LHC.

Amongst the magnet development program of a large-aperture Nb3Sn superconducting quadrupole for the Large Hadron Collider luminosity upgrade, six quadrupole magnets were built and tested using a shell based key and bladder technology (TQS). The 1 m long 90 mm aperture magnets are part of the US LHC Accelerator Research Program (LARP) aimed at demonstrating Nb3Sn technology by the year 2009, of a 3.6 m long magnet capable of achieving 200 T/m. In support of the LARP program the TQS magnets were tested at three different laboratories, LBNL, FNAL and CERN and while at CERN a technology-transfer and a four days magnet disassembly and reassembly were included. This paper summarizes the fabrication, assembly, cool-down and test results of the six magnets and compares measurements with design expectations.

The LHC insertions are equipped with individually powered superconducting quadrupole assemblies comprising several quadrupole magnets and orbit correctors, and range in length from 5.3Â m to 11.3Â m. Following the initial experience in the assembly of the pre-series cold masses, the production has advanced well and about half of the total of 82 units has been produced at CERN. In this paper we present the experience gained in steering the cold mass production, in particular with respect to the alignment requirements. We also report on the field quality and other measurements made for assuring the quality of the quadrupoles.

Special individually powered superconducting quadrupoles are required for the LHC insertions. These units comprise quadrupole magnets of the MQM and MQY types and range in length from 5.4 m to 11.4 m. In total, 82 insertion quadrupoles will be assembled at CERN. In this paper we present the advance in construction of the magnets and report on the performance of the first series built units, including power tests and alignment of the cold masses.

In the present work, we report the characterization of the partial cDNA sequence of a bile salt-activated lipase (BAL) cDNA from haddock. The predicted polypeptide encoded by the cDNA sequence contains the bile salt-binding site characteristic of all BALs at amino acid positions 36–45, and the lipid-binding site thus far only reported in fish BALs starting at position 345. Other features of BAL are also present including: the active site serine motif at positions 111–117, the catalytic triad formed by the residues S114, D239 and H358, and an N-glycosylation site at position 107. The relative levels of BAL gene expression were determined in haddock larvae during ontogeny by reverse transcription–polymerase chain reaction (RT–PCR) with the earliest detectable transcript levels identified at hatch. Using in situ hybridization, the BAL transcripts were localized consistently in the pancreas of haddock larvae from mouth opening until 401 degree days (DD). Using biochemical techniques, the specific activity of BAL was found to decline significantly over time. Our results also suggest that haddock larvae are capable of digesting lipids at the time of mouth opening.

Energy resource management and energy auditing are two effective methodologies which lead to a rational energy use in the different processes or systems in the industrial sector. This article introduces a methodology focused on energy management through the monitoring of variables as well as the results obtained from its application in “Industrias Alimenticias NOEL S.A., ZENU” plant in Medellin, Colombia. The aim of this methodology is to identify the main sources of energy waste, the way energy is used, and the possibilities for better energy exploitation. The analysis consisted of the periodical measurement of electricity, fuel, water, and propane gas consumption, as well as steam generation, which are then compared to production output (consumption vs. production). Through lineal regression techniques, fixed (baseline) and variable consumption are determined for the comparison. This way, unnecessary consumption and system efficiency data are obtained respectively. By implementing this techniqu...

The partial sequencing of two lipases from winter flounder Pseudopleuronectes americanus, one most closely related to gastric, lingual and lysosomal acid lipase from other vertebrates and one most closely related to bile salt-activated lipase, is reported. Biochemical analyses of enzymatic activity demonstrated the greater contribution made by bile salt-activated lipase relative to neutral bile salt-independent lipase. Using molecular techniques, the tissue-specific expression of bile salt-activated lipase in pancreatic tissue and acid triacylglycerol lipase in a wide variety of organs was demonstrated. Furthermore, the developmental expression of these types of lipase in larval fish was established.

The design, fabrication and tests of a new generation of superconducting magnets for the upgrade of the LHC require the support of an adequate, robust and reliable sensing technology. The use of Fiber Optic Sensors is becoming particularly challenging for applications in extreme harsh environments such as ultra-low temperatures, high electromagnetic fields and strong mechanical stresses offering perspectives for the development of technological innovations in several applied disciplines.

New generation of accelerator magnets for high energy applications currently designed, manufactured and tested at the European Organization for Nuclear Research (CERN) require the implementation of precise cryogenic sensors with long-term robustness and reliability able to withstand cryogenic temperature and to monitor the mechanical stresses affecting the winding during all the stages of his service life, assembly, cool down and powering. Monitoring the mechanical behavior of the magnet from assembly to operation is a critical task which aims to assure the integrity of the magnet and to safely handle the coils made of new brittle material. This contribution deals with the first successful embedding of Fiber Bragg Grating sensors in a subscale Nb$_{3}$Sn dipole magnet in order to monitor the strain developed in the coil during the cool down to 1.9 K, the powering up to 15.8 kA and the warm up, offering new perspectives for the development of a complementary sensing technology based on fiber optic sensors.

This article discusses the results obtained by computing 4 different quantitative metrics for the assessment of the upper limb, using the elbow angle as the datum for the experiment. This angle was obtained from a commercial Motion Tracking system with 19 subjects: 10 with cerebral palsy (CP) and 9 with no neurological impairment. Subjects performed one task, consisting in reaching a small object (elbow extension) and bringing it to their mouths (elbow flexion). A MATLAB toolbox was implemented in order to compute the logarithmic dimensionless jerk metric, the mean arrest period ratio, the spectral arc-length metric and the peaks metric, as well as the maximum peak angle, minimum peak angle, maximum peak velocity, maximum peak acceleration and minimum angular acceleration. Results show the consistency of the spectral arc-length metric to display the differences between CP and healthy subjects, while the peaks metric and the logarithmic dimensionless jerk metric tend to be useful under some restrictions. With this analysis, a preliminary motor impairment assessment can be deducted, by comparing the metrics data from the CP subjects with the control group.

In the present study, the establishment and validation of an ovarian biopsy method for in vivo assessment of oocyte maturation in the snook, Centropomus medius Gunther, is described. Diameter and morphological characteristics of intra-ovarian oocytes siphoned with a polyethylene cannula were analysed fresh, preserved with 1% formalin in 0.7% NaCl solution and also cleared with Serra solution. There were no effects detected of the preservative solution on the opaque oocytes within the 24-h interval of the test. The clearing solution allowed excellent visibility of the membrane thickness, yolk appearance and germinal vesicle. Oocytes from each of the five ovarian sites of all examined females were in different prematuration stages and those on the tertiary yolk globule stage had a unimodal diameter frequency distribution and their diameter means were not significantly different among sites (P > 0.01) on eight females. In vivo and in vitro samples of the eight females examined were not significantly different (P > 0.05). As samples obtained with the polyethylene cannula are representative of the ovary central portion, an estimate of the coefficient of variation corrected for bias (P

We argue that a description of supersymmetric extended objects from a unified geometric point of view requires an enlargement of superspace. To this aim we study in a systematic way how superspace groups and algebras arise from Grassmann spinors when these are assumed to be the only primary entities. In the process, we recover generalized spacetime superalgebras and extensions of supersymmetry found earlier. The enlargement of ordinary superspace with new parameters gives rise to extended superspace groups, on which manifestly supersymmetric actions may be constructed for various types of p-branes, including D-branes (given by Chevalley-Eilenberg cocycles) with their Born-Infeld fields. This results in a field/extended superspace democracy for superbranes: all brane fields appear as pull-backs from a suitable target superspace. Our approach also clarifies some facts concerning the origin of the central charges for the different p-branes., Latex file, 31 pgs. Version to appear in NPB

After defining cohomologically higher order BRST and anti-BRST operators for a compact simple algebra {\cal G}, the associated higher order Laplacians are introduced and the corresponding supersymmetry algebra $\Sigma$ is analysed. These operators act on the states generated by a set of fermionic ghost fields transforming under the adjoint representation. In contrast with the standard case, for which the Laplacian is given by the quadratic Casimir, the higher order Laplacians $W$ are not in general given completely in terms of the Casimir-Racah operators, and may involve the ghost number operator. The higher order version of the Hodge decomposition is exhibited. The example of su(3) is worked out in detail, including the expression of its higher order Laplacian W., Comment: 31 pages, two figures, latex2e file. Replacement (May 14, 1999): a comment and references added. To appear in JMP

It is shown that the family of deformed algebras has a different bicrossproduct structure for each in analogy to the undeformed case.

Acid soils severely reduce maize (Zea mays L.) yield in the tropics. Breeding for tolerance to soil acidity provides a permanent, environmentally friendly, and inexpensive solution to the problem. This study was carried out to determine the relative importance of additive, dominant, and epistatic effects on maize grain-yields in different tropical genotypes. Divergent selection in three populations (SA4, SA5, and SA7) provided inbred lines tolerant or sensitive to acid soils. The tolerant and sensitive lines from each population were used to obtain the F1, F2, F3, back-crosses, second back-crosses, and selfed back-cross generations. In addition, the tolerant lines from SA4 and SA5 were crossed with a sensitive line from the Tuxpeno Sequia population, from which the same generations were also derived. All generations from each of the five sets of crosses were evaluated in three acid-soil environments and one non-acid-soil environment. A generation-mean analysis was performed on each set for yield. The sequential sum of squares associated with additive, dominance, and digenic epistatic effects were used to estimate the relative importance of each genetic effect. Epistasis was not important in any set in the non-acid-soil environment, with dominance accounting for 80.76% of the total variation among generation means across sets. In acid-soil environments, epistasis was more important. The relative importance of digenic epistasis was greater in those evaluations with large experimental errors. The tolerant line from population SA5 was prone to severe root lodging, suggesting a very poor root system. Apparently, the tolerance to soil acidity in this line is not associated with a large root system.

The structure and electric conductivity of glasses in the system R NO 3 –Zn(NO 3 ) 2 –KHSO 4 –P 2 O 5 ( R = Na, K) obtained at different temperatures were investigated by IR and impedance spectroscopy. Glasses fused at 250–350 °C demonstrated an increase of their ionic conductivity in 10 3 times in comparison with the same compositions fused at 550 °C. The influence of the chemical composition on the structure and properties of the obtained glasses was analyzed. It is proposed that the high ionic conductivity of glasses obtained at low temperatures is related to the incorporation of the nitrate ions between long (PO 3 ) n chains, similar to the iodide ions; this resulted in a maximal coordination of the local conduction space for the cation associated with a disordered glass network.