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Subtotal coil embolization followed by subsequent flow diversion is often pursued for treatment of acutely ruptured aneurysms. Owing to the need for anti-platelet therapy, the optimal time of safely pursuing flow diversion treatment has not been fully elucidated. In this study, we aim to demonstrate the safety and feasibility of staged treatment of acutely ruptured aneurysms with early coil embolization followed by flow diversion prior to discharge. A retrospective study to evaluate clinical outcomes of patients who presented with aneurysmal subarachnoid hemorrhage and underwent coil embolization followed by subacute flow diversion treatment during the same hospitalization. A total of 18 patients are included in our case series. Eight patients presented with Hunt-Hess (H-H) grade 2 bleed, 6 patients with H-H grade 3, and 2 patients each with H-H grade 4 and H-H grade 1. Eight patients required placement of an external ventricular drain on admission. After initial coil embolization, 12 achieved Raymond-Roy grade 2 occlusion, and 6 attained grade 3a/b occlusion. The mean duration between coil embolization and subsequent flow diversion was 9.83 days (range: 1–30). There were no instances of re-hemorrhage between initial coil embolization and subsequent flow diversion treatment. Sixteen patients had a minimum of 6-month follow-up, of which 15 were found to have complete occlusion, and 1 required subsequent clipping. Subtotal coil embolization followed by definitive treatment using flow diversion during the same hospitalization is feasible and achieves excellent aneurysm occlusion rates while avoiding dual anti-platelet therapy during the initial hemorrhage period. [ABSTRACT FROM AUTHOR]

Endovascular therapy is the first-line treatment for the cavernous sinus dural arteriovenous fistulas, particularly transvenous embolization. This study aimed to assess the trans-superior ophthalmic vein approach to embolization for its safety, efficacy, and viability as a first-line treatment in selected patients, with a description of the microsurgical and endovascular techniques. We retrospectively reviewed patients with cavernous sinus dural arteriovenous fistulas treated using the direct superior ophthalmic vein approach with n-butyl cyanoacrylate and coils as the main embolic materials from 2015 to 2021. The safety and efficacy of the treatment were evaluated based on ocular and neurological improvement, angiographic obliteration, and recurrence. Of the 16 patients, all cases were diagnosed with cavernous sinus dural arteriovenous fistulas. The n-butyl cyanoacrylate was used as the sole embolic material in 12 cases, and coils were used in 4 cases. A direct superior ophthalmic vein approach was selected as the first option in 11 patients. All the patients achieved complete fistula obliteration and good recovery from ocular symptoms, accompanied by excellent cosmetic results. No recurrence was observed at a mean follow-up period of 26 months. Microsurgical dissection for exposure and direct cannulation of the superior ophthalmic vein as a route for fistula obliteration delivers excellent clinical outcomes, with a low rate of complications. Not only is it safe and effective as an alternative approach but it can also serve as first-line treatment in selected patients. [ABSTRACT FROM AUTHOR]

• Magnetorheological fluid concentrations affect mutual inductance between coils. • The frequency response characteristic exists in coil mutual inductance. • The coil mutual inductance exhibits a linear correlation with the concentration. • Multiplexed excitation coils for in-use dampers are practical for health monitoring. Magnetorheological (MR) fluid-based applications have accelerated new approaches for vibration and shock control in civil engineering structures and automobile suspensions. The sedimentation phenomenon happens once the MR fluid keeps static, which limits practical realizations of commercial products. Most existing methods of sedimentation evaluation are still at the laboratory stage, which is helpless in the face of the severe operating conditions of the real damper. Based on the twin-tube MR damper, a mutual inductance-based MR fluids monitoring scheme for in-use dampers was proposed in this paper, meanwhile, being compatible with the MR damper magnetic circuit. It is identified that the scheme effectively measures the concentration of MR fluid from 0% to 45 vol%, without any additional electro-sensitive components inside the cylinder. Also, online sedimentation monitoring experiments have been successfully carried out with MR fluid(10 vol% and 30 vol%) [ABSTRACT FROM AUTHOR]

Coronary artery perforation (CAP) is a rare but potentially life-threatening complication of percutaneous coronary intervention (PCI), however if recognized and managed promptly, its adverse consequences can be minimized. Risk factors for CAP include the use of advanced PCI technique (such as atherectomy and chronic total occlusion interventions) and treatment of severely calcified lesions. There are 3 major types of CAP depending on location: (a) large vessel perforation, (b) distal vessel perforation, and (c) collateral perforation. Large vessel perforation is usually treated with implantation of a covered stent, whereas distal and collateral vessel perforations are usually treated with coil or fat embolization. In this article we provide a state-of-the-art overview of the contemporary management of CAP. [ABSTRACT FROM AUTHOR]

The incidence of traumatic arteriovenous fistula (TAVF) between the middle meningeal artery (MMA) and the petrosal vein (PV) is rare. Although TAVF has been reported involving the MMA several sinus and veins, this is the first incidence of a fistula involving the extracranial MMA and PV. We present a 47-year-old male with sudden onset of weakness of his right limb and speech difficulty a few hours before admission to our facility. He had a 6-month history of mild traumatic head injury. Initial computed tomography revealed midbrain hemorrhage while digital subtraction angiography revealed a TAVF of the left MMA. Enhanced magnetic resonance imaging, however, revealed communication between the MMA and PV. We treated the patient with coil embolization via the transarterial route. This is the first incidence of a fistula connecting the extracranial MMA and PV. We managed the patient with only coil embolization without any further neurologic deficits. [ABSTRACT FROM AUTHOR]

In this article, two analytical formulas for the calculation of mutual inductance between a circular filament and line segment arbitrarily positioning in the space are derived by using Mutual Inductance Method (MIM) and Babic's Method (BM), respectively. Using the fact that any curve can be interpolated by a set of line segments, a method for calculation of mutual inductance between a circular filament and filament having an arbitrary shape in the space is proposed based on the derived analytical formulas. The derived two formulas and the proposed method (Segmentation Method) were numerically validated by using FastHenry software and reference examples from the literature. In particular, the proposed method was successfully applied to the calculation of mutual inductance between the circular filament and the following special curves such as circle, circular arc, elliptic arc, ellipse, spiral, helices and conical helices. All results of the calculation are in good agreement with the reference examples. • Novel two formulas for calculation of MI between a circle and line are obtained. • These formulas are derived by using methods of MIM and BM. • Segmentation method for calculation of MI between a circle and curve is proposed. [ABSTRACT FROM AUTHOR]

• We describe the design of the MB and PF joints in ITER. • The joints preparation for hydraulic characterization is detailed. • The hydraulic test sequence is explained. • The main results are highlighted. • The consequences on the cryoplant operation are raised. The ITER magnet system will be the largest superconducting magnet system ever built. The system, all inside a cryostat, is mainly composed of a Central Solenoid (CS) split in 6 modules, a set of 18 Toroidal Field (TF) d -shaped coils and 6 Poloidal Field (PF) coils. Each of these coils uses variable type of cable-in-conduit-conductors (CICC) actively cooled by a forced supercritical helium flow. Their electrical supply from the current feedthrough of the cryostat is done with Main Busbars (MB) using similar CICC. The electrical MB to coils as well as internal PF and TF coils connections rely on the twin box concept developed by CEA in the early R&D phase. After electrical validation of joint prototypes for the PF and the MB conductors on full size samples, specific hydraulic characterization tasks were done through the Magnet Infrastructure Facilities for ITER (MIFI) contract between ITER Organization (IO) and CEA devoted to develop, improve and qualify manufactured components and assembly processes. These tasks were done on the samples using the CEA OTHELLO dedicated facility able to operate with gaseous N 2 in a large Reynolds range at room temperature. The paper explains the way followed to get a full hydraulic characterization of the MB and PF5 joints for the two flow directions. The study of the flow distribution between parallel cooling channels inside the PF5 joint revealed a bypass of the active joint region. The paper reports on this hydraulic behaviour in the relevant magnets operating conditions and outlines the design changes in the joints provoked by the results of this study. [ABSTRACT FROM AUTHOR]

• A new analytical formulation for calculation of the mutual inductance is presented. • The formula is derived via a generalisation of the Kalantarov-Zeitlin method. • The obtained formula provides a solution for the singularity issue arising in the Grover and Babic formulas. In this article, we present a new analytical formulation for calculation of the mutual inductance between two circular filaments arbitrarily oriented with respect to each other, as an alternative to Grover (1944) and Babič et al. (2010) expressions reported in 1944 and 2010, respectively. The formula is derived via a generalisation of the Kalantarov-Zeitlin method, which showed that the calculation of mutual inductance between a circular primary filament and any other secondary filament having an arbitrary shape and any desired position with respect to the primary filament is reduced to a line integral. In particular, the obtained formula provides a solution for the singularity issue arising in the Grover and Babič formulas for the case when the planes of the primary and secondary circular filaments are mutually perpendicular. The efficiency and flexibility of the Kalantarov-Zeitlin method allow us to extend immediately the application of the obtained result to a case of the calculation of the mutual inductance between a primary circular filament and its projection on a tilted plane. Newly developed formulas have been successfully validated through a number of examples available in the literature, and by a direct comparison with the results of calculation performed by the FastHenry software. [ABSTRACT FROM AUTHOR]

Highlights • Standard coiling for parent vessel sacrifice is lengthy and expensive due to large number of coils. • Parent vessel sacrifice with the combination of PODs and standard coils appear to be a feasible, safe, and effective alternative to the traditional vessel sacrifice techniques. • Combination of PODs and standard coils require less coils and achieve satisfactory occlusion with reducing procedural and fluoroscopy times. Abstract Purpose The purpose of this study is to describe the use of the Penumbra Occlusion Device (POD), which is a coil with an enhanced anchor segment, along with standard coils for carotid and vertebral artery sacrifice, and to assess its feasibility, safety, and efficacy. Methods This is a retrospective chart review of patients with vessel sacrifices who were treated using POD. For the procedure, a balloon test occlusion was performed prior to permanent arterial sacrifice. Following this, a POD was deployed followed by subsequent angiography to confirm occlusion. Secondary PODs or standard coils were deployed as necessary. Results A total of 5 internal carotid arteries and 5 vertebral arteries were treated in 10 patients. The mean vessel diameter of the vessel sacrificed was 4 mm (range 2.9–7.7 mm). The total mean number of coils required for vessel sacrifice was 7 (range 3–17). The mean number of PODs used for vessel sacrifice was 2.4 (range, 1–6). The mean number of additional standard coils used was 4.1 (range, 0–13). 9/10 (90%) parent arteries were successfully occluded. One patient had slow flow distal to the occluded segment. One (10%) of the patients had a delayed ischemic event. There were no immediate periprocedural complications including coil migrations or vessel dissections. 6/10 patients had follow-up imaging and no patients developed recanalization during the follow-up period. Conclusion Parent vessel sacrifice using a combination of PODs and standard coils appear to be a feasible, safe and effective alternative to the traditional vessel sacrifice techniques. [ABSTRACT FROM AUTHOR]

The paper studies the dimensional accuracy of additively manufactured (AM) coil winding structures for small experimental stellarators fabricated under industrial non-laboratory conditions. Insufficient accuracy is one of the main issues hindering the use of additive manufacturing (AM) for coil windings structures (coil casings and coil forms or frames) for stellarators. The dimensional accuracy of one complex modular coil frame and four planar coil casings is studied for different AM techniques and materials, in particular Selective Laser Sintering (SLS) in polyamide, Stereolithography (SLA) in resin, Fused Deposition Modelling (FDM) in ABS and PolyJet in resin. The measurements are performed by a Mitutoyo Coordinate Measuring Machine. The AM parts are hollow for subsequent internal casting with (fibre-reinforced) resin for strength and performance enhancement, method named 3Dformwork. The paper reports the features of the sample parts, the metrology methodology utilised, the performed measurements and the resulting dimensional deviations for each AM technique. Professional AM in FDM showed deviation between nominal dimensions and measurements of ±0.1% (one sigma, 68% of measurements) and PolyJet ±0.15%. Personal web-based AM in SLA exhibited deviation ±0.3% and SLS in polyamide ±0.4% (one sigma). The PolyJet part showed dimensional instability under harsh environment and would require immediate 3Dformwork. The FDM part presented the lower cost for the particular case study among the professional AM. Thus, high quality PolyJet and FDM additive manufacturing in plastics are at the verge of achieving the requirement of 0.1% minimum accuracy for stellarator coil windings. Therefore, AM may contribute to the fabrication of accurate winding structures for stellarators and other accurate components in fusion. [ABSTRACT FROM AUTHOR]

This paper presents a method for calculating the internal voltage transients useful for power transformer winding modelling. The method is based on lumped parameter model of a transformer winding and the transient response is obtained using time-domain analysis. Lumped circuit parameters are calculated using self-developed solvers which are benchmarked using professional finite element method (FEM) software. The results show that the presented approach gives satisfactory results and is computationally very fast. [ABSTRACT FROM AUTHOR]

The following article overviews recent studies regarding heat transfer enhancement methods, explicitly focusing on fins and coils utilization, in phase change material-based latent heat thermal energy storage systems. It discusses the influence of various geometrical and material parameters on the melting and solidification processes, as well as the orientation of the heat transfer surface within the storage tank. Additionally, the article examines the use of a range of phase change materials regarding their melting temperature. Results show that there are research gaps regarding a few ranges of phase change materials of certain previously studied melting points. This paper's main goal was to detect possible research gaps within the phase change studies field. It should be highlighted that a vast amount of numerical studies of both finned and coiled geometries is in need of experimental verification. More than 62% of analyzed studies were performed numerically, while only 37% were performed experimentally. What is more, there were only a few studies concerning experimental investigations for melting temperatures higher than 60 °C. Furthermore, the majority of experimental as well as numerical studies were concerned only with melting phenomena. This paper also advocates for more standardized studies regarding coil geometries using non-dimensional parameters. [ABSTRACT FROM AUTHOR]

This paper presents a fast and precise method for the calculation of internal voltage transients over the voltage instrument transformer windings. Lumped circuit parameters of the transformer winding are calculated using self-developed solvers based on the boundary element method and integral equations approach. A detailed equivalent circuit of the transformer winding is solved in time domain. Test model of the voltage instrument transformer is constructed with a number of measurement points along the windings. Results of the calculation are in a good agreement with the measured voltages. [ABSTRACT FROM AUTHOR]

Objective/Background To evaluate the safety, efficacy, and medium-term outcome of a modified technique of ethanol embolisation of mandibular arteriovenous malformations (AVMs) following a direct percutaneous transvenous approach to the release of coils via a microcatheter. Methods From January 2012 to July 2014, 18 consecutive patients (mean age 20.9 years [range 10–35 years]) with symptomatic AVMs of the mandible were enrolled. A microcatheter was inserted into the lesion via a direct percutaneous puncture needle. Electrolytically detachable coils and 0.018 mm coils were super-selectively placed to decrease the flow and volume of the arteriovenous fistulas via a microcatheter. Absolute ethanol was injected to obliterate the fistulas. Clinical follow-up was performed in all patients. Therapeutic outcomes were determined by evaluating the degree of devascularisation at follow-up angiography and symptoms and signs. Results Transvenous release of coils combined with absolute ethanol embolisation were used in all cases. The amount of ethanol used ranged from 5 to 50 mL (mean 25.7 mL) in a single session. Sixteen of 18 patients were cured, and two had partial remission. Follow-up times ranged from 8 to 26 months (medium 15.7 months), and there was no angiographic recurrence of the lesions. Minor complication occurred in five of the 18 patients. There were no major complications. Conclusion Absolute ethanol embolisation following a direct percutaneous transvenous approach to release coils via a microcatheter is a feasible, safe, and highly effective method for the management of mandibular AVMs. [ABSTRACT FROM AUTHOR]

This paper presents a methodology to estimate internal convective heat transfer coefficients in ducts, using only data available at an exterior boundary. The methodology is based on the reciprocity function approach, which does not require any intrusive measurements and it needs low computational resources because it avoids the use of iterative techniques. The unknown function can be estimated by solving a linear system, where the solution vector is composed of integrals of the boundary data. Numerical results are presented, where the stability of the method is tested against different functions, with high levels of noise. In the final part of the paper, for a real test case, using measurements taken by an infrared camera, the method is analyzed and compared with a traditional technique, showing very good results. The estimate can be performed in less than 3 s, using an inexpensive Raspberry Pi computer (less than US$28), equipped with a Broadcom BCM2835 system on a chip (SoC) processor. [ABSTRACT FROM AUTHOR]

Within the framework of the Broader Approach, the French voluntary contributor represented by CEA awarded a contract for the production of 9 toroidal field coils for the JT-60SA project to Alstom, Belfort, France in mid-2011. A first preparatory phase was led to establish the team, produce the manufacture drawings, define the manufacturing process, procure the required tooling and prepare the quality documentation. In parallel, a qualification phase on the critical major processes has proved Alstom's ability to master the processes and reach the requirements. After reviewing of the qualification results and modification of the processes and tooling to overcome the encountered difficulties, a Production Readiness Review has authorized Alstom to start the production winding. A prototype double pancake was wound as the first of series. In addition to complying with the pancake width all around the D shape, the straightness of the centreline in the critical straight leg part was correct. The production of the successive double pancakes to constitute the first winding pack was then completed and the joints and terminals were manufactured. The paper describes the completion of the last qualifications and the status of the winding production. [ABSTRACT FROM AUTHOR]

Background Peptic ulcers in pediatric populations are uncommon and can present with upper gastrointestinal bleeding and shock on presentation. An endoscopy is done initially to identify bleeding source. However, definitive treatment is achieved with angiography. The use of coiling is effective in achieving hemorrhagic control in duodenal ulcers or gastric ulcers, particularly in adults. However, the use in pediatric populations is unknown. We present a case of peptic ulcer disease treated with a gastroduodenal artery coil in a pediatric patient that has never been reported in the literature. Case presentation A 15-year-old male with a five-year history of peptic ulcer disease was admitted with an upper gastrointestinal bleed. Angiographic imaging was done to isolate and locate the bleeding, and coil embolization of the gastroduodenal artery was performed. Coils eroded into intestinal lumen but bleeding was controlled. Conclusion Peptic ulcers in pediatric populations are rare and complex in nature. Besides aggressive resuscitation and endoscopy, other methods to control bleeding such as coil embolization can be performed. Further investigations are needed to understand long-term effects of coil embolization in pediatric peptic ulcer patients. Level of evidence 5/Case Report/. [ABSTRACT FROM AUTHOR]

Objective A subarachnoid hemorrhage is neurologically devastating, with 50% of patients becoming disabled or deceased. Advent of Guglielmi detachable coils in 1995 permitted endovascular treatment of cerebral aneurysms. Coiling is efficacious and safe, but durability needs improvement, as nearly 20% of patients require further invasive intervention secondary to aneurysm recurrence. The aim of this study is to develop an in vitro model of endothelial cell (EC) proliferation and differentiation on four types of platinum-based coils, using gene expression profiling to understand EC biology as they colonize and differentiate on coils. Methods Human umbilical vein ECs were grown in vitro on platinum coil segments. Growth patterns were assessed as a function of coil type. Gene expression profiles for coil attached versus coil unattached ECs were determined using immunohistochemistry and gene array analysis. Results ECs showed rapid, robust attachment to all coil types. Some detachment occurred within 24–48 hours. Significant growth of remaining attached cells occurred during the next week, creating a confluence on coils and within coil grooves. Similar growth curve results were obtained with human brain ECs on platinum-based coil surfaces. Differentiation markers in attached cells (α 1 , α 2 , β 1 integrins) were expressed on immunostaining, whereas microarray gene expression revealed 48 up-regulated and 68 down-regulated genes after 24-hour growth on coils. Major pathways affected as a function of time of colonization on coils and coil type included those involved in regulation of cell cycle and cell signaling. Conclusions We developed an in vitro model for evaluating endothelialization of platinum coils to optimize coil design to support robust EC colonization and differentiation. [ABSTRACT FROM AUTHOR]

Geometric complexity of stellarators hampers a straightforward production of conceived optimised magnetic configurations. Integration of the engineering design with new fabrication methods may reduce the production cost and accelerate the production process. A fast cycle production of experimental fusion devices also might result in a faster advance in fusion plasma science. Several different stellarators could be used to test configurations for improved turbulent transport or to validate new divertor configurations. In this framework, and based on the results from the previously built UST_1 stellarator, the present work try to study and validate the feasibility of 3D printing methods (additive manufacturing) for small experimental stellarators. The paper summarises the engineering development, fabrication and validation of a coil frame test sector for the UST_2 stellarator. The definition of the Last Closed Flux Surface and winding surface for the test sector is based on an optimised quasi-isodynamic poloidal stellarator, modified for enhanced in-vessel remote handling manipulation and wide space for divertors. A Filled-sparse coil frame concept is developed to still keep low the cost in spite of the present expensive 3D printing materials and printers. [ABSTRACT FROM AUTHOR]

In this article, formulas for calculation of magnetic force and torque between two circular filaments arbitrarily oriented in space were derived by using Kalantarov–Zeitlin's method. Formulas are presented in an analytical form through integral expressions, whose kernel function is expressed in terms of the elliptic integrals of the first and second kinds, and provide an alternative formulation to Babič's expressions. The derived new formulas were validated via comparison with a series of reference examples. Also, we obtained additional expressions for calculation of force and torque between two circular filaments by means of differentiation of Grover's formula for the mutual inductance between two circular filaments with respect to appropriate coordinates. These additional expressions allow to verifying comprehensively and independently derived new formulas. [Display omitted] • A set of formulas for calculation of magnetic force and torque were derived. • Formulas are presented in an analytical form through integral expressions. • Formulas were derived by using Kalantarov-Zeitlin's method. [ABSTRACT FROM AUTHOR]

Due to its compactness, high heat and mass transfer rate and ease of manufacture, coiled/spiral tube has been widely used in process industries, especially as heat exchangers and chemical reactors. This study addresses the mass-transport enhancement and reaction performance in in-plane spiral reactor with various cross sections geometries, i.e. circular, half-circular, rectangular, square, trapezoidal and triangular, at fixed cross-section area at several Reynolds numbers. The mass transfer performance is compared with those of straight channel counterpart. Laminar flow of gas with catalytic reactions is investigated using a validated three-dimensional computational fluid dynamics (CFD) model. The results suggest that spiral ducts offer better reaction performance as compared to straight duct, especially at higher Reynolds number. However, it imposes higher pressure drop. Amongst various cross-section, the coil reactor with half-circular geometry yields the highest reaction performance. This study can provide insight for design guidelines of high performance coiled reactor. [ABSTRACT FROM AUTHOR]

Abstract: Expressions are presented for the inductance of a curved circular spiral coil in free space and the change in impedance when the coil is wrapped around the surface of a magnetic, conductive cylinder. Inductance and impedance measurements of a thin conformable coil on a cylindrical Al-alloy rod were used to test the validity of these expressions. The theoretical predictions are in very good agreement with the experimental measurements over the frequency range 1kHz–10MHz. The findings are compared with previous work using rectangular spiral coils and it was found that the change in normalized impedance at high frequencies for a circular coil was almost identical to that obtained for a similarly-sized square coil. The implications for use in eddy-current nondestructive testing are discussed. [Copyright &y& Elsevier]

Abstract: Background: Embolic coils have been used to treat intracranial aneurysms using an endovascular approach for more than two decades. However, significant aneurysm recanalization rates have been reported specifically in large and giant aneurysms. Adding filaments to bare Platinum coils is considered a modification and has been proposed to achieve higher aneurysm occlusion rates as compared to bare Platinum coils. Quantitative information — in terms of thrombin generation potential of these modifications — is however lacking. Objective: We report here in vitro thrombogenicity of Platinum coils containing Nylon (Axium™ MicroFx™ Nylon coil) and PGLA (Axium™ MicroFx™ PGLA coil) filaments and compare them with equivalent bare Platinum Axium™ coils. Method: We utilize a quantitative method that tracks the formation of thrombin upon exposure of the test samples to human platelet rich plasma using a slow binding fluorogenic substrate. Results: We report a significant increase in the total thrombin turnover, the peak thrombin amount and the rate of thrombin generation for the Axium™ MicroFx™ coils and filaments compared to the Axium™ coils and Platinum wire. Conclusion: Nylon and PGLA filaments added to bare Platinum coils increase thrombogenicity of coils. This study offers a robust quantitative method to compare thrombus formation efficacy of embolic coils under static conditions. [Copyright &y& Elsevier]

Abstract: Following the first conceptual design activity in which the general design of the JT-60SA TF system was defined in agreement with all the participants in the project (CEA, ENEA, F4E), a second phase dealing with the detailed design was engaged by each of the voluntary contributors. For the French part which includes the procurement of 9 of the TF winding packs and their integration in the casing, an industrial contract was signed mid 2011 with Alstom (France). Several actions have been carried out to prepare the manufacturing phase. To precisely define one of the main interfaces which is the temporary electrical connection of the coils to the current leads during cold test in the CEA facility as well as their final connection to the feeders at the Naka site, a design compatible with both requirements was developed by CEA, supported by the previous developments led on the joints and assembly techniques. In addition to prepare the coils manufacture, hydraulic qualification was led on the first conductor qualification length to set the parameters which will be used by the coils manufacturer for conductor acceptance. At last, mechanical characterizations of both the conductor and of the empty compacted jacket were performed in order to define as precisely as possible the elastic and plastic properties of these components. These are crucial properties used during the bending process which is one of the most important operations during the winding pack manufacture. These data will be very helpful for the winding machine parameters settings as well as for designing the local bending tooling needed to shape the conductors extremities at the connection area and at the double pancakes joggles. [Copyright &y& Elsevier]

To fulfill the requirements for ITER in-vessel magnetic diagnostics, several coil prototypes have been developed, aiming at minimizing the disturbing effects of temperature gradients and radiation induced phenomena. As a first step in the radiation resistance testing of these prototypes, an in-situ high dose rate gamma radiation test on a selection of prototypes was performed. The aim of this test was to get a first experimental feedback regarding the behavior of the pick-up coil prototypes under radiation. Five prototypes (a coil wound with glass-insulated copper wire, two LTCC coils and two HTCC coils) were irradiated at a dose rate of 46kGy/h up to a total dose of 72MGy and at a temperature of 50°C. During the irradiation, the continuity resistances and the insulation resistances were continuously measured. Before and after irradiation reference data were recorded as a function of temperature (from 30°C to 130°C). This paper includes the results of the temperature and irradiation tests and a discussion of the behavior of the prototype coils in terms of electrical and mechanical properties. [ABSTRACT FROM AUTHOR]

Usually, electric vehicle systems are based on various modules that should ensure the high power and stability of the vehicle on the track. The majority of these components are linked to the charging mechanism. In this regard, dynamic wireless power transfer is a practical method to solve electric vehicle range anxiety and reduce the cost of onboard batteries. Wireless recharging has long been common with pure electric vehicles and is designed to allow charging even when the vehicle is in motion. However, it is difficult to analyze this method since its operating philosophy is complex, particularly with the existence of several variables and parameters. Also, the state of the vehicle, whether it is in motion or not, defines several parameters such as the vehicle speed as well as the sizes and dimensions of the coil receivers. This paper presents a novel method to improve the performance of the dynamic wireless recharge system. In the proposed system, receiver coils have been added to maximize charging power by offering a dynamic mathematical model that can describe and measure source-to-vehicle power transmission even though it is in motion. In the proposed mathematical model, all physical parameters describing the model were presented and discussed. The results showed the effectiveness of the proposed model. Also, the experimental tests confirmed the validity of the simulation results obtained by providing two coil receivers under the vehicle. [ABSTRACT FROM AUTHOR]

Since the conception of balloon-occluded retrograde transvenous obliteration (BRTO) of gastric varices 25 years ago, the placement of an indwelling balloon for hours has been central to the BRTO procedure. Numerous variables and variations of the BRTO procedure have been described, including methods to reduce sclerosant, combining percutaneous transhepatic obliteration, varying sclerosant, and using multiple sclerosants within the same procedure. However, the consistent feature of BRTO has always remained the indwelling balloon. Placing an indwelling balloon over hours for the BRTO procedure is a logistical burden that taxes the interventional radiology team and hospital resources. Substituting the balloon with hardware (coils or Amplatzer vascular plugs [AVPs] or both) is technically feasible and its risks most likely correlate with gastrorenal shunt (GRS) size. The current authors use packed 0.018- or 0.035-in coils or both for small gastric variceal systems (GRS size A and B) and AVPs for GRS sizes up to size E (from size A-E). The current authors recommend an indwelling balloon (no hardware substitute) for very large gastric variceal system (GRS size F). Substituting the indwelling balloon for hardware in size F and potentially size E GRS can also be risky. The current article describes the techniques of placing up to 16-mm AVPs through balloon occlusion guide catheters and then deflating the balloon once it has been substituted with the AVPs. In addition, 22-mm AVPs can be placed through sheaths once the balloon occlusion catheters are removed to further augment the 16-mm Amplatzer occlusion. To date, there are no studies describing, let alone evaluating, the clinical feasibility of performing BRTO without indwelling balloons. The described techniques have been successfully performed by the current authors. However, the long-term safety and effectiveness of these techniques is yet to be determined. [Copyright &y& Elsevier]

Abstract: We investigate the use of 2nd-generation High-Temperature Superconductors (2G-HTSs) in the rotors of electrical motors and generators. For these devices the conductor must be wound into robust impregnated coils, which are operated in vacuum at temperatures around 30K, in strong magnetic fields of about 2T. Differences in thermal contraction between the coil former, conductor constituents, impregnation resin, bandage and heat-sink materials (assembled at room temperature) cause mechanical stresses at operating temperature. Rotating-machine operation adds Lorentz forces and challenging centripetal accelerations up to thousands of g. Second generation-HTS conductors withstand large tensile stresses in axial direction and compression in normal direction. However, shear stresses, axial compression, and tension normal to the conductor can cause degradation in superconducting properties. Such stresses can be mitigated by correct choice of materials, coil lay-out and manufacturing process. A certain stress level will remain, which the conductor must withstand. We have manufactured many impregnated round and race-track coils, using different 2G-HTS conductors, and tested them at temperatures from 25K to 77K. Degradation of the superconductor in early coils was traced to the mentioned differences in thermal contraction, and was completely avoided in coils produced later. We will discuss appropriate coil-winding techniques to assure robust and reliable superconductor performance. [Copyright &y& Elsevier]

Abstract: A numerical approach is carried out to investigate the heat transfer performance of in-plane spiral ducts with various cross sections – rectangular, square, triangular, trapezoidal, circular and half circular. Simulations were carried out at a constant inlet Reynolds number at fixed cross section area for both constant wall temperature and constant wall heat flux conditions. Results are compared to straight ducts of the same cross sections and at the same length as the coiled ducts. The effects of Reynolds number and Prandtl number are also discussed for various geometries. The results are presented and are aimed to determine the advantages, limitations and effects of in-plane spiral ducts of various cross sections on the flow and heat transfer characteristics when the cross section area is fixed. [Copyright &y& Elsevier]

Abstract: The national spherical torus experiment (NSTX) will be upgraded to provide increased toroidal field, plasma current and pulse length. This involves the replacement of the so-called center stack, including the inner legs of the toroidal field (TF) coil, the Ohmic heating (OH) coil, and the inner poloidal field (PF) coils. In addition the increased performance of the upgrade requires qualification of remaining existing components for higher loads. Initial conceptual design efforts were based on worst-case combinations of possible currents that the power supplies could deliver. This proved to be an onerous requirement and caused many of the outer coils support structures to require costly heavy reinforcement. This has led to the planned implementation of a digital coil protection system (DCPS) to reduce design-basis loads to levels that are more realistic and manageable. As a minimum, all components must be qualified for the increase in normal operating loads with headroom. Design features and analysis efforts needed to meet the upgrade loading are discussed. Mission and features of the DCPS are presented. [Copyright &y& Elsevier]

Abstract: Purpose: Tiny intracranial aneurysms pose a significant therapeutic challenge for interventional neuroradiologists. The authors report their preliminary results of endovascular treatment of these aneurysms. Methods: Between January 2002 and December 2009, 52 tiny intracranial aneurysms (defined as ≤3mm in maximum diameter) in 46 patients (22 men; mean age, 57.9years) were treated by endosaccular coil embolisation or sole stent deployment in the parent artery. Of 52 aneurysms, 29 had ruptured and 23 remained unruptured. The initial angiographic results, procedural complications, and clinical outcomes were assessed at discharge. Imaging follow-up was performed with cerebral angiography. Results: One aneurysm coiling procedure failed because of unsuccessful micro-catheterization. Forty-three aneurysms were successfully coil embolized, of which complete occlusion was obtained in 14, subtotal occlusion in 18 and incomplete occlusion in 11. The other 8 aneurysms were treated by sole stent deployment in the parent artery. Procedural complications (2 intraprocedural ruptures and 3 thromboembolic events) occurred in 5 (9.6%) of 52 aneurysms, resulting in permanent morbidity in only 1 (2.2%, 1/46) patient. No rebleeding occurred during clinical follow-up (mean duration, 46.7months). Of the 16 coiled aneurysms that receiving repetitive angiography, 6 initially completely and 3 subtotally occluded aneurysms remained unchanged, 4 initially subtotally and 3 incompletely occluded aneurysms progressed to total occlusion. Five sole stent deployed aneurysms received angiographic follow-up (mean duration, 10.0months), of which 3 remained unchanged, 1 became smaller and 1 progressed to total occlusion. Conclusion: Endovascular treatment of tiny intracranial aneurysms is technical feasible and relatively safe. Coil embolisation seems to be effective in preventing early recanalisation, whereas sole stenting technique needs further investigation to determine its effectiveness. [Copyright &y& Elsevier]

Abstract: Recent results from our group and from literature data are summarized. Emphasis is put on the various supported catalysts that can lead to the formation of helical (or coiled) carbon nanotubes. Detailed analysis of transmission electron microscopy images reveals that not all types of nanotubes – having any type of coil pitch and coil diameter – are equally probable: stability islands can be found in the 3D representation of the number of nanotubes as a function of both coil pitch and coil diameter. In most of the cases the coils are formed by introducing pairs of five-membered and seven-membered rings into the nanotubes containing the basic six-membered rings. Possible applications of the helical carbon nanotubes are discussed. [Copyright &y& Elsevier]

Abstract: The performance of electromagnetic-thermal non-destructive inspection is investigated experimentally by eddy current thermography. The experiments concerned the detection of the crack in ten square aluminum plates at various positions and orientations. For the excitation are employed two circular coils with an outer diameter either smaller or comparable to the plate side. Crack detection is based not only on the thermograms, but on data processing techniques as well. Despite the fact that the performance of the infrared camera used is relatively low and the exciting frequency was only 50Hz, the coil with small section detected effectively the nine cracks out of the ten while the coil with large section detected effectively seven out of ten. [Copyright &y& Elsevier]

Abstract: The JT-60SA is a fusion experiment designed to contribute to the early realization of fusion energy by addressing key physics issues for ITER and by investigating how best to optimize the operation of the fusion power plants. The superconducting magnet system of JT-60SA consists of three sub-systems: a Central Solenoid split in four segments, a set of six Equilibrium Field coils and a set of eighteen Toroidal Field coils. Such systems are connected each other by means of a series of flexible and kinematic mechanical attachments, with the Toroidal Field magnet acting as the backbone of the whole magnet system. A detailed finite element model, representing a 40 degrees sector of the superconducting magnet system of JT-60SA, has been developed and a complete set of analyses were carried out to obtain the distribution of magnetic forces acting on the three magnet sub-systems, to predict the corresponding deformations, to estimate the stress levels in the magnets’ mechanical structures and to verify the integrity of the system and its fatigue life, in agreement with the applicable Codes and Standards and in consideration of the expected lifespan of the machine. This paper illustrates the details of the modeling strategy which lead to the production of the finite element model and provides a comprehensive report and a critical analysis of the most relevant results obtained in the calculations carried out so far. [Copyright &y& Elsevier]

Abstract: In an attempt to learn more about molecular mechanisms and thermodynamic preconditions of development of spatial structures of starch systems, the authors analyzed the kinetics of structuralization processes in the temperature function of the course of these processes. The method of dynamic-mechanical analysis (DMA) was employed in the performed investigations. On the basis of empirical values of G1 and G2, the energetic status of the gel network as well as changes in this status during the structuralization process was determined. In the state of complete hydration, the retrogradation mechanism of the examined starch systems consisted in the bundle–coil transition. This transition required a decline in the temperature of the system below temperature θ determined by the ratio of the enthalpy to entropy transition: ΔH/ΔS ≈ 322 K ≈ 49 °C. This transition is a cooperative transformation of two fragments of neighboring chains in a condition of chaotic confrontation to a state of bihelical associated molecules. The bihelical association of starch chains is the main source of stabilization of the spatial structure of starch hydrogels below the θ transition temperature. [Copyright &y& Elsevier]

Abstract: This paper is focused on the design, simulation and optimisation of the ITER divertor magnetic tangential coils. The most critical issue for the divertor coils is to minimise RITES and TIEMF [R. Vila, E.R. Hodson, Thermally induced EMF in unirradiated MI cables, J. Nucl. Mater. 367–370 (Part 2) (2007) 1044–1047] by combining a proper choice of conductor with low temperature variation in the coil. Instead of mineral insulated cable (MIC), which was foreseen as the preferred winding, a winding made of ceramic-coated steel wire was recently proposed [G. Chitarin, L. Grando, S. Peruzzo, C. Tacconet, Design developments for the ITER in-vessel equilibrium Halo current sensors, 24th SOFT Conference, Warsaw, Poland, September 2006, Fusion Eng. Design, in press]. It is thought that, for this wire, maintaining a temperature variation in the wiring below 10K will be sufficient to allow long-pulse operation. Variations of the divertor coil design have been simulated with the help of ANSYS. The aim was to keep the temperature variation in the winding pack within this limit. The optimisation of the coil based only on a cooling by conduction was not sufficient to meet the 10K target. Therefore, an actively water-cooled coil was designed which finally met these requirements. [Copyright &y& Elsevier]

Abstract: Background: An internal carotid artery (ICA) injury is an uncommon but potentially fatal complication of transsphenoidal surgery. Case Description: We report a 61-year-old male patient with a right cavernous ICA injury sustained during transsphenoidal surgery and who underwent endovascular Stent graft placement. The ICA trapping was not indicated because of the absence of the left A1 on preoperative magnetic resonance angiography. During Stent graft placement, the ICA wall could not be completely fit with a stent due to its stiff nature and the carotid curve. The gap between the stent and the ICA wall was filled using a coiling procedure on the first postoperative day. Conclusions: Endovascular Stent graft placement for posttranssphenoidal carotid artery injury is a useful technical adjunct to the management strategy and has the potential to minimize the risk of having to sacrifice the ICA. In cases of incomplete reconstruction of the Stent graft placement due to its stiff nature and the carotid curve, an additional coiling procedure could be helpful to obliterate the gap between the stent and the ICA wall. To avoid carotid injury during transsphenoidal surgery, careful preoperative evaluation of vascular structures and meticulous surgical technique are necessary. [Copyright &y& Elsevier]

Abstract: In this paper it is shown the design and characterization of a differential electromagnetic sensor. In absence of the sample the output signal of the sensor is null. There will only be an output signal in the presence of a magnetic material or a conductive sample in which eddy currents are generated, producing an external magnetic field. This working principle is non invasive and improves greatly the possibilities for signal conditioning. The sensor has been tested with a copper sample and for detection of variations in the blood glucose concentration, showing high sensitivity and potentialities for other applications. [Copyright &y& Elsevier]

Abstract: The central solenoid (CS) of the ITER tokamak contributes to the inductive flux to drive the plasma, to the shaping of the field lines in the divertor region and to vertical stability control. It is made of 6 independent coils, using a Nb3Sn cable-in-conduit superconducting conductor, held together by a vertical precompression structure. This design enables ITER to access a wide operating window of plasma parameters, up to 17MA and covering inductive and non-inductive operation. Each coil is based on a stack of multiple pancake winding units to minimise joints. A glass–polyimide electrical insulation, impregnated with epoxy resin, is giving a high voltage operating capability, tested up to 29kV. The CS performance is fatigue driven mainly by the stress levels in the conductor jacket and in the precompression structure needed to keep the modules in contact during the repulsive forces which can arise in operation. A rigid connection to the TF coils provided at one end and a centering support at the other end allow to resist net vertical forces as well as unbalanced radial forces while avoiding torsion transmission from the TF Coils to the CS assembly. [Copyright &y& Elsevier]

Abstract: An experimental investigation regarding two-phase diabatic pressure drops inside a helically coiled heat exchanger have been carried out at SIET thermo-hydraulics labs in Piacenza (Italy). The experimental campaign is part of a wide program of study of the IRIS innovative reactor steam generator. The test section consists of an AISI 316 stainless steel tube, 32m length, 12.53mm inner diameter, curved in helical shape with a bend radius of 0.5m and a helix pitch of 0.8m, resulting in a total height of the steam generator tube of 8m. The explored operating conditions for two-phase flow experiences range from 192 to 824kg/m2 s for the mass flux, from 0 to 1 for the quality, from 1.1 to 6.3MPa for the pressure, from 50 to 200kW/m2 for the heat fluxes. A frictional two-phase pressure drops correlation, based on an energy balance of the two-phase mixture and including the 940 experimental points, is proposed. Comparison with existing correlations shows the difficulty in predicting two-phase pressure drops in helical coil steam generators. [Copyright &y& Elsevier]

Abstract: A method for making weighted linear combinations of the spectra acquired by a phased-array coil is described. Unlike most previous combination methods, no special reference points in the data are chosen to represent the coil weights. Instead, all the data points are used, which results in optimal signal-to-noise ratio more reliable estimation. The method uses singular value decomposition to identify the coil weights and extract the principal component of variation in the signal. Subsequent processing of the combined signal (e.g., Fourier transform, baseline correction, phasing) may proceed as per a single coil acquisition. [Copyright &y& Elsevier]

Abstract: Industrial studies have been carried out in Europe to prepare the manufacture of the five poloidal field (PF) coils, which will be manufactured on the ITER site. A first study, carried out by Ansaldo Superconduttori, addressed the manufacturing sequence, assuming the manufacture of the PF coils inside the two buildings which will further host the cryogenic system. A second study, carried out by Alstom investigated how to achieve the manufacture of some crucial points. A new layout of the manufacturing line was proposed, aiming at manufacture of the PF2–6 coils within 36 months. A recent study performed by Alstom, assumes the manufacture of the PF coils in a single dedicated building, releasing so the constraint of meeting the deadline fixed in ITER reference scheme by the starting point of installation of the cryogenic components. [Copyright &y& Elsevier]

Abstract: Since 2001 when magnesium diboride (MgB2) was first reported to have a transition temperature of 39K, conductor development has progressed to where MgB2 superconductor wire in kilometer-long piece-lengths has been demonstrated in magnets and coils. Work has started on demonstrating MgB2 wire in superconducting devices now that the wire is available commercially. MgB2 superconductors and coils have the potential to be integrated in a variety of commercial applications such as magnetic resonance imaging, fault current limiters, transformers, motors, generators, adiabatic demagnetization refrigerators, magnetic separation, magnetic levitation, energy storage, and high energy physics applications. This paper discusses the progress on MgB2 conductor and coil development in the last several years at Hyper Tech Research, Inc. [Copyright &y& Elsevier]

Abstract: The present paper reports results from an investigation of the air side thermal performance of fin-and-tube coils with herringbone-wavy and convex-louver fins. The tube diameter of the tested coils was 12.7mm. Coils with different fin pitch and tube rows have been tested in order to determine their effect over the thermal performance. In addition, the performance of the convex-louver fins has been evaluated with respect to that of the wavy fins according to the Webb VG1 procedure. The collar diameter Reynolds number covered in the tests varied from 1000 to 6000, corresponding to face velocities of 1–6m/s. It has been found that the fin pitch affects lightly the heat transfer coefficient, its value being incremented of the order of 10% by reducing the fin pitch from 3.17mm to 1.81mm. Opposite trends have been found for the friction factor of wavy and louver fins regarding the effect of the fin pitch. The thermal performance is not affected by the number of tube rows in either of the fin configurations in coils for more than two rows. One and two row coils present non-negligible differences either with respect to the Colburn or friction factors. It has been found that area reductions in louver with respect to wavy fins can attain values of the order of 30% for Reynolds number of the order of 1000 and fin pitch of 3.17mm. [Copyright &y& Elsevier]

Abstract: The international thermonuclear experimental reactor (ITER) toroidal field (TF) magnet system consists of 18 superconducting coils using a 68kA Nb3Sn conductor. In order to guarantee the performances of these coils prior to their installation, the test of at least one prototype coil at liquid helium temperature and full current is required. The test of all coils in the two-coil test configuration, with successive charging of each coil to nominal current is recommended. This requires a large test facility. [Copyright &y& Elsevier]

This article outlines the tools used by interventional neuroradiologists to treat giant aneurysms. The basic philosophy and techniques, including recent advances, are discussed in some detail. In particular, the relatively new stent technologies offer an additional weapon in the armentarium for treating these challenging lesions. Stent-assisted aneurysm coiling has significantly expanded the range of lesions that can successfully be treated endovascularly and represents a major advance in the field. [Copyright &y& Elsevier]