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Marbofloxacin, a veterinary–exclusive antimicrobial drug of third–generation fluoroquinolone class, exhibits wide spectrum antimicrobial activity against Gram-negative as well as Gram-positive bacteria, and thus, is a promising agent to treat susceptible bacterial infections in poultry. Therefore, the present study was conducted to derive dosage regimen of marbofloxacin based on the results of intravenous and oral pharmacokinetic (PK) trial in sixteen healthy broiler chickens. Plasma concentrations of marbofloxacin were measured by optimized and in-house validated Ultra High Performance Liquid Chromatography (UHPLC) method. The PK parameters were calculated from plasma concentrations versus time data by non-compartmental analysis using ‘PK Solver 2.0’ software. Following oral administration of marbofloxacin at the dose rate of 5 mg/kg body weight, the mean maximal plasma concentration (Cmax: 2.193 µg/ml) was achieved at 1.68 h. Marbofloxacin showed long half-life (6.03 h), high volume of distribution (2.64 L/Kg) and good oral bioavailability (88.10 %). The average plasma concentration of marbofloxacin ≥ 0.32 µg/ml was maintained upto 12 h and 0.10 µg/ml at 24 h. Based on the values of PK-PD integrated indices, it is concluded that oral dose of marbofloxacin @ 5.0 mg/kg body weight, to be repeated at 24 h, would be efficient to treat common bacterial pathogens of broiler chickens having MIC ≤ 0.12 μg/ml.

The recent trends in High Temperature Superconductor (HTS) development and HTS based applications have led to the exploration of various methods for achieving cryogenic temperature suitable for the superconducting cables and magnet characterization. An existing test facility at ITER-India has been augmented to deliver 80 K helium for testing, particularly for thermo-hydraulic characterization of superconducting cables. Such characterization is very important for the prediction of performance during operation to ensure adequate mass flow rate through the cable for heat load removal and to maintain the cable stability. The facility is capable of supporting the test on a superconducting short sample at 80 K with a mass flow rate up to 35 g/s and pressure up to 7 bar(a) using helium as a fluid. The functional acceptance of the developed test facility has been performed with the first experiment conducted on a short coiled shaped mock sample cable-in-conduit conductor (CICC). The longitudinal friction factor obtained from the measurement has been compared with the existing correlations for Reynolds number ranging between 50-400. The wound CICC short sample has been analyzed using Computational Fluid Dynamics (CFD) approach, considering the bundled region as a porous media to cover a wide range of various thermo-hydraulic and geometrical parameters involved in the test sample. A comparison of the experimental and the CFD simulation results is presented.

Purpose: To determine the bronchodilatory effect of ginger on histamine-induced bronchospasm in guinea pigs. Methods: Thirty-six guinea pigs weighing 400 - 700 g were randomly divided into six groups. Group 1 received distilled water, while group 2 was given formoterol (1.55 μg/kg) + budesonide (0.02 mg/kg). Guinea pigs in groups 3 and 4 were given ginger (350 and 700 mg/kg, respectively), while those in groups 5 and 6 received ginger (350 and 700 mg/kg, respectively) in addition to formoterol (1.55 μg/kg) and budesonide (0.02 mg/kg). Pre-convulsion time and percent protection in each group was calculated. Results: There was statistically significant improvement in pre-convulsion times, with values of 156.64 ± 32.93, 299.33 ± 44.20, and 235.99 ± 34.55 s for groups 2, 5 and 6, respectively (p < 0.01). Moreover, statistically significant protection values of 73 and 68 % were obtained for groups 5 and 6, respectively, relative to normal control (p < 0.01). Conclusion: These results indicate that ginger has promising potential for use as an add-on treatment for bronchospasm. Keywords: Zingiber officinale, Histamine, Asthma, Pre-convulsion time

To review the literature using a systematic approach to answer the question: 'Are zirconia dental implants an alternative to titanium dental implants?' This was evaluated by assessing the evidence for survival rate, success rate and marginal bone loss of the two implant materials.Relevant studies were identified after searching PUBMED, EMBASE and the Cochrane library. Two reviewers assessed the papers using the specified inclusion criteria, title and abstracts. Studies that were not related to the outcomes of: survival rate, success rate or marginal bone loss of zirconia dental implants were excluded.From a total of 1617 titles and abstracts, 33 potentially relevant full text papers were identified. Of these, 18 met the criteria for inclusion in the review. The review revealed heterogeneity between the studies in terms of surgical characteristics, implant characteristics, defining success and measuring marginal bone loss therefore making comparisons between studies difficult. However, in the three randomised control studies included in this review, which compared zirconia implants to titanium implants, the survival rate was lower for zirconia implants, but the success rate and marginal bone loss were found to be similar.Overall, initial studies indicate that zirconia dental implants could be a viable alternative to titanium implants but need further well-designed studies need to be carried out to assess their long-term survival rate, success rate and marginal bone loss. At present, zirconia implants should be used with caution but can be an alternative option if a patient has an absolute contraindication to titanium.

The Cold Compressor (CC) is used to lower the saturation temperature of liquid helium (LHe) under varying heat load conditions from the application side, i.e. superconducting magnets and cryopumps for large Tokamak machines. The CC is a key component of a typical cold box, attached to the LHe bath, which compresses and transfers the vapor generated during the heat exchange via heat exchangers as well as the flash generated downstream from the Joule-Thomson (JT) valve connected to the cryoplant. The emphasis of the present paper is a conceptual design and performance assessment of the CC. The CC is designed to pump 0.33 kg/sec of 4.2 K saturated helium vapor at a pressure ratio of 1.39; with an off-design range of 0.2–0.5 kg/sec. Operating speeds are between 10 and 25 krpm, with a speed of 17 krpm at the design point. Due to different heat loads from superconducting magnets and cryopumps, different process pressure and flow rates of the CC for large tokamak machines are expected. Hence, as an important component of the CC, the impeller design with blade profile generation has been carried for the higher thermodynamic efficiency of the CC. Characteristics curves of the CC have been obtained at different speed values. Analysis has been carried out using computational fluid dynamics (CFD) tool to analyze various situations during real operation.

Systemic lupus erythematosus (SLE) can be induced by various medications, such as hydralazine, procainamide, isoniazid, methyldopa, chlorpromazine, quinidine, and minocycline. A patient was admitted complaining of fever with chills and rigor. After being diagnosed with tuberculous meningitis, the patient was given antituberculosis treatment. As the patient did not improve, detailed investigations were conducted, and elevated antinuclear antibody levels were found. The consulting physician diagnosed that the patient was suffering from SLE. As isoniazid is associated with an increased risk of developing SLE, it was suspected as the culprit drug. After withdrawing isoniazid from the antituberculosis treatment regimen, the patient improved and was discharged. Based on the WHO-UMC and Naranjo’s causality assessment criteria, an association between the reaction and isoniazid was deemed probable. The reaction was moderately severe (level 4b) according to the modified Hartwig and Siegel scale.

The ITER superconducting (SC) magnet system, which consists of central solenoid coils, toroidal field (TF) coils, TF structures, and poloidal field and correction coils, is cooled by supercritical helium (SHe) circuits located in dedicated auxiliary cold boxes (ACBs) of the cryodistribution (CD). Due to the increase in the nuclear heat load during the deuterium-tritium plasma phase, the necessary cooling power to maintain the thermal stability of the magnet system can be beyond the presently designed and contracted specification of the cryoplant (LHe and liquid nitrogen plants). Increasing the cryoplant capacity or performance in turn will significantly increase the project cost apart from the impacts on the utility infrastructures (cooling water, electricity, civil works, etc.). In this paper, we will present arrangements within the CD for an efficient and flexible operation. Instead of a common control, which is the present design, by individually controlling the LHe bath temperature of the ACBs, the cooling power can be concentrated to the magnet system in need (reduction in the SHe circuit temperature). In addition to this, a proposal to minimize the heat of compression of the cold rotating machines in order to further allocate the cooling power to the SC magnet system will be introduced.

Superconducting (SC) magnets with Cable in Conduit Superconductor (CICSC) winding, cooled by helium at 4 K temperature are employed for many applications which require high magnetic field and high current densities. The construction of CICSC aims to maintain superconductivity state by optimization of various parameters, i.e., thermal stability, ratio of normal conductor to superconductor material, mechanical strength, low hydraulic impedance, current density, magnetic field, etc. The cryogenic thermal stability of the CICSC is of prime importance for the safe, stable and reliable operation of SC magnets. The prediction of thermal and hydraulic behaviour of CICSC in large SC magnets is difficult due to the complex geometry, variation of fluid properties, various heat in-flux incidences over the long length of CICSC and a complex heat transport phenomenon. Here we present a CFD approach for the thermal hydraulic analysis of a typical CICSC applying the porous media analogy and discuss the suitability for a wider range of operational scenario at higher Reynolds number and for various geometries.

The constantly increasing energy consumption along with the depleting fossil fuel resources as well as owing to the fact that the nuclear fission not being an intrinsically safe method of energy generation, it has become necessary to look for other solutions to fulfil the future energy demands. Nuclear fusion, the source of energy for billions of stars, has attracted the attention of scientists and engineers despite a lot of technical challenges in the replication of the fusion process in laboratories. For fusion to take place in a device, one of the major challenges faced is the strong magnetic confinement of the plasma using large superconducting (SC) magnets, which need efficient cryogenic cooling techniques to maintain the required low temperatures for the superconducting state. In order to maintain the compactness, the SC magnets generally employ Cable in Conduit Conductor (CICC) windings, carrying high current densities, which are cooled by the forced flow of helium at ~4 K temperature to maintain the required superconducting temperatures. The construction of CICC aims to maintain the superconductivity state by optimization of various parameters such as thermal stability, the ratio of normal conductor to SC material, mechanical strength, low hydraulic impedance, current density, magnetic field, etc. The cryogenic thermal stability of the CICC is of prime importance for safe, stable and reliable operation of SC magnets. The prediction of thermal and hydraulic behavior of the CICC in large SC magnets is difficult due to the complex geometry involved, the variation in fluid properties, various heat in-flux incidences over the long length of CICC and a complex heat transport phenomenon. Another application which utilizes a forced flow cryogenic cooling in the fusion devices is a cryo-adsorption pump for creating clean and high vacuum with large pumping speed. This paper presents an overview of the forced flow cryogenic cooling schemes in fusion devices along with a systematic review of the thermal and hydraulic studies related to CICC and cryo-adsorption pump, thereby highlighting the challenges and opportunities for further improvement in their design and performance., Fusion, superconducting magnets, cryogenics, thermo-hydraulic, CICC, cryopump.

Auxiliary Cold Boxes (ACBs) of ITER cryodistribution system has multiple cryogenic process volumes as well as interfaces with cryolines having isolated vacuum spaces. Cryogenic process volumes inside a single vacuum space have different temperature levels, 4 K and 80 K as well as different operating pressure, 5 bar(a) and 18 bar(a). Cryogenic process volumes including interfacing cryolines are protected with safety devices (e.g. Safety Relief Valves (SRVs) and Rupture Discs (RDs)). In an accidental event like Loss of Insulation Vacuum (LIV) of any particular vacuum space, incidental heat load of order of ∼6.5 kW/m2 results in rapid pressurization of cryogenic process volume; considering safety of cryolines excess pressure is to be relieved through SRVs. As per nuclear safety requirements of ITER, maximum helium inventory inside tokamak building is restricted; hence, a common relief header is necessary to collect SRVs discharge and carry it outside tokamak building. Due to long length of relief header, required information regarding backpressure on SRVs is not known in advance. The backpressure is a function of geometric condition of relief header, process condition of relieving process volume and relieving mass flow rate. The estimation of backpressure considering steady-state condition and maximum mass flow rate through all connected SRVs may result in a conservative and unrealistic value. Therefore, a dynamic simulation of safety relief event along with complete model of process volume, boundary conditions as well as geometric detail of relief header is performed using pressure-flow solver model in Aspen HYSYS®. Two simulation approaches are considered for present study to estimate backpressure (i) Steady state maximum mass flow model, which considers maximum relieving mass flows of SRVs computed from code (EN13648-3) (ii) Dynamic mass flow model, which considers the size of SRVs from code and process pressure, mass flow evolve with time based on heat load applied on process volumes. The results of backpressure from two simulation approaches are discussed and outcome of study is summarized.

ITER, an experimental fusion reactor uses solenoid valves to close cryogenic control valves instantly in case of any incidental event in the ITER cryogenic system takes place. Many of these solenoid valves are functioning with the magnetic field environment of the order of ∼25 m T. Since a solenoid valves is an electrically activated valve, presence of the environment magnetic field can lead to partial or non-closing of the valve. In this paper, the effect of magnetic field environment on the performance of 3/2 solenoid valves through simulation and experiment is studied. The variable external magnetic field is generated by supplying variable power from Switched Mode Power Supply (SMPS) to the magnetic coil and magnetic field readings are recorded with a tesla meter. The validation of the magnetic field profile of the magnetic coil is done by comparing the E-mag analysis simulation performed on ANSYS® platform and the experimental results. An experiment setup, inside ITER-India cryogenic laboratory, has been assembled to see the functionality of the 3/2 solenoid valve in the presence of an external magnetic field. A 3/2 solenoid valve is placed in the external magnetic field which has been generated with the help of an air core inductor magnetic coil. The external magnetic field from the coil is varied from 10 m T to 35 m T with the help of a variable power supply and checked the functionality of the solenoid valve in different orientation and different external magnetic fields strengths. The outcome of the study shows that the 3/2 solenoid valve stopped functioning over the external magnetic field strength of 14.29 m T. The paper also concludes the requirement of the magnetic shielding and correct orientation of the solenoid valves to be installed in order to nullify the effect of external magnetic field on the functionality of the 3/2 solenoid valves.

Fixed drug eruption (FDE) was caused by fixed-dose combination (FDC) of antituberculosis drugs in the form of tablet Forecox® (rifampicin [rifampin] 225 mg + isoniazid 150 mg + pyrazinamide 750 mg + ethambutol 400 mg) in a 40-year-old male patient with a history of drug allergy. The patient developed FDE after taking the third dose of tablet Forecox® for pulmonary tuberculosis. Tablet Forecox® was withdrawn and the patient recovered from the reaction after 15 days of treatment for FDE. As per World Health Organization–Uppsala Monitoring Centre (WHO-UMC) and Naranjo causality assessment criteria, the association between the reaction and tablet Forecox® was possible and probable, respectively. The reaction was moderately (Level 4b) severe according to the Modified Hartwig and Siegel scale. As there is an increased risk of allergic reaction in patients with a history of drug allergy, FDCs should not be used in order to avoid complexity in identifying the culprit drug.

Complex and large cryogenic distribution systems are integral part of a fusion machine having superconducting magnets, cryopumps, etc. The various equipment of the cryogenic distribution system are interconnected via Cryogenic Transfer Lines (CTLs) to distribute cold helium to end users. During nominal operation of the fusion machine, helium inventory in CTLs could be in order of several tons. The cold helium present in CTLs could be released in surrounding volume due to accidental scenario. The present analysis, aims to estimate lowest temperature in the surrounding volume due to accidental scenario. The paper will describe simulation results and the test plan in a simulated condition.

Background Surgical extraction of third molars is associated with postoperative pain and swelling at the extraction site. Pain is commonly managed using non-steroidal anti-inflammatory drugs (NSAIDs). Postoperative pain is usually moderate to severe in the first 12 h postoperatively and lasts for 3–5 days. However, with NSAIDs, these symptoms usually subside within 24 h. Diclofenac sodium and etodolac are NSAIDs, more selectively cyclooxygenase-2 inhibitors, with good analgesic efficacies. Methods We compared the safety and analgesic efficacy of diclofenac sodium with etodolac peroral after surgical extraction of third molars in a double-blind, double-dummy, parallel-group study. The subjective pain improvement and pain relief after 2, 6, 24, 48, and 72 h using the visual analogue scale were measured as the study outcome. Results Etodolac was equivalent to diclofenac sodium in pain alleviation at all postoperative time periods. No significant differences were found between diclofenac sodium and etodolac groups (P > 0.05). Both study medications were well tolerated and safe with mild adverse effects in only a few participants. Conclusion Diclofenac sodium and etodolac are comparable in terms of analgesic efficacy and safety after surgical removal of third molars.

Since the conceptual design of the ITER Cryodistribution many modifications have been applied due to both system optimization and improved knowledge of the clients' requirements. Process optimizations in the Cryoplant resulted in component simplifications whereas increased heat load in some of the superconducting magnet systems required more complicated process configuration but also the removal of a cold box was possible due to component arrangement standardization. Another cold box, planned for redundancy, has been removed due to the Tokamak in-Cryostat piping layout modification. In this proceeding we will summarize the present design status and component configuration of the ITER Cryodistribution with all changes implemented which aim at process optimization and simplification as well as operational reliability, stability and flexibility.

Operation and control of superconducting (SC) magnets in the fusion devices having tokamak configuration opens up the domain of varying peak thermal energy environment as a function of time, commensurate with the plasma pulses. The varied thermal energy environment, thus propagated to upstream of the cooling system, is responsible for the system level instability of the overall cryogenic system. The cryogenic distribution system, the regime of first impact point, therefore, has to be tuned so as to stay at the nearly stable zone of operation. The configuration of the cryogenic distribution system, considered in the present study, involves a liquid helium (LHe) bath as a thermal buffer, LHe submerged heat exchangers and cold circulator apart from the valves for implementations of the precise controls. The cold circulator supplies the forced flow supercritical helium, used for the cooling of SC magnets. The transients of the thermal energy pulses can be attenuated in the cryogenic distribution system by various methodologies. One of the adopted methodologies in the present study is with the precise speed control of the cold circulators. The adopted methodology is applied to various configurations of arrangements of internal components in the distribution system for obtaining system responses with superior attenuation of energy pulses. The process simulation approach, assumptions, considered inputs and constraints, process modeling with different configuration as well as results to accomplish the control scheme for the attenuation of the thermal energy pulses are described.Operation and control of superconducting (SC) magnets in the fusion devices having tokamak configuration opens up the domain of varying peak thermal energy environment as a function of time, commensurate with the plasma pulses. The varied thermal energy environment, thus propagated to upstream of the cooling system, is responsible for the system level instability of the overall cryogenic system. The cryogenic distribution system, the regime of first impact point, therefore, has to be tuned so as to stay at the nearly stable zone of operation. The configuration of the cryogenic distribution system, considered in the present study, involves a liquid helium (LHe) bath as a thermal buffer, LHe submerged heat exchangers and cold circulator apart from the valves for implementations of the precise controls. The cold circulator supplies the forced flow supercritical helium, used for the cooling of SC magnets. The transients of the thermal energy pulses can be attenuated in the cryogenic distribution system by var...

The ITER project design foresees Supercritical Helium (SHe) forced flow cooling for the main cryogenic components, namely, the superconducting (SC) magnets and cryopumps (CP). Therefore, cold circulators have been selected to provide the required SHe mass flow rate to cope with specific operating conditions and technical requirements. Considering the availability impacts of such machines, it has been decided to perform evaluation tests of the cold circulators at operating conditions prior to the series production in order to minimize the project technical risks. A proposal has been conceptualized, evaluated and simulated to perform representative tests of the full scale SHe cold circulators. The objectives of the performance tests include the validation of normal operating condition, transient and off-design operating modes as well as the efficiency measurement. A suitable process and instrumentation diagram of the test valve box (TVB) has been developed to implement the tests at the required thermodynamic conditions. The conceptual engineering design of the TVB has been developed along with the required thermal analysis for the normal operating conditions to support the performance evaluation of the SHe cold circulator.

The system of ITER Cryodistribution (CD) and Cryolines (CLs) is an integral interface between the Cryoplant systems and the superconducting (SC) magnets as well as Cryopumps (CPs). The project has progressed from the conceptual stage to the industrial stage. The subsystems are at various stages of design as defined by the project, namely, preliminary design, final design and formal reviews. Significant progresses have been made in the prototypes studies and design validations, such as the CL and cold circulators. While one of the prototype CL is already tested, the other one is in manufacturing phase. Performance test of two cold circulators have been completed. Design requirements are unique due the complexity arising from load specifications, layout constraints, regulatory compliance, operating conditions as well as several hundred interfaces. The present status of the project in terms of technical achievements, implications of the changes and the technical management as well as the risk assessment and its mitigation including path forward towards realization is described.

The cold circulators, the most challenging component of ITER cryo-distribution system, have been designed, manufactured and tested successfully at factory. The design point for the cold circulator has been specified as 2.21 kg/s at 4.3 K inlet temperature having 0.155 MPa pressure head, dedicated for the nominal operation of toroidal field (TF) superconducting magnet of ITER. The expected isentropic efficiency has been defined as 70 % or more suitable to cater the demands of the cryo-distribution system. Two cold circulators for TF superconducting magnet have been installed in the Test Auxiliary Cold Box (TACB) followed by the integration of TACB system with the 5.0 kW at 4.5 K class cryogenic test facility at Japan. Final cold acceptance test of the complete system has been performed in order to validate the design conditions of TACB and cold circulators. Qualification tests of two cold circulators have been executed at closed loop operating condition. The cool-down of cold circulators down to 4.6 K temperature level and normal operating results as well as the experimental validation of performance along with the obtained isentropic efficiencies at the operating conditions have been demonstrated meeting the system level requirements of ITER cryo-distribution.

The test auxiliary cold box (TACB) has been designed for the qualification test of ITER cold circulator. The test loop in the TACB has been designed by incorporating various components and this test loop will undergo different operation modes. The exergy analysis has been performed for the test loop including all involved components to check their thermal performance and Irreversibility. The result shows the contribution of exergy destruction and exergy efficiency for the test loop as well as individual components during nominal operating case; cold circulator inlet pressure ∼0.5 MPa and inlet temperature ∼4.6 K. The analysis result has been captured the loop pressure variation between 0.5 MPa to 2 MPa in order to evaluate the balance between thermodynamically efficient process conditions and actual requirements, even though above 1 MPa pressure is not foreseen during the cold circulator test. The exergy based analysis approach for the cryogenic test loop show a path towards efficient process conditions at higher loop pressure and identify the inefficiencies in the various components.

The prototype cryoline (PTCL) for ITER is a representative cryoline from the complicated network of all cryolines for the project. The PTCL is being designed with four process pipes at temperature level 4.5 K, two process pipes at 80 K and will be manufactured in a 1:1 scale with a configuration of main line and branch line including vacuum barriers. The test objectives are focused to demonstrate best possible risk free engineering and reliable manufacturing of the cryolines as per the ITER functional requirements. The measured physical parameters will assess the confirmation for acceptable heat loads, stresses and mechanical integrity in normal, off-normal and accident scenarios such as a break of insulation vacuum (BIV). The PTCL will be tested to measure heat load at 4.5 K with scaled mass flow rate having the thermal shield at 80 K. Necessary infrastructure along with the control system have been designed, analyzed and optimized within the imposed constraints to fulfill the test objectives. The system approach along with instrumentations and controls, results of the optimization study, and its usefulness in the present context within the constraints of economics and schedule have been described.

Cryogenic distribution system (CDS) plays a vital role for reliable operation of largescale fusion machines in a Tokamak configuration. Managing dynamic heat loads from the superconducting magnets, namely, toroidal field, poloidal field, central solenoid and supporting structure is the most important function of the CDS along with the static heat loads. Two concepts are foreseen for the configuration of the CDS: singular distribution and collective distribution. In the first concept, each magnet is assigned with one distribution box having its own sub-cooler bath. In the collective concept, it is possible to share one common bath for more than one magnet system. The case study has been performed with an identical dynamic heat load profile applied to both concepts in the same time domain. The choices of a combined system from the magnets are also part of the study without compromising the system functionality. Process modeling and detailed simulations have been performed for both the options using Aspen HY...

The ITER cryo-distribution and cryoline is a part of the in-kind supply for India. The design of the systems is in progress. The topology of torus and neutral beam cryoline is defined as six process pipes along with thermal shield at 80 K and outer vacuum jacket. In order to develop confidence in the concept and to establish the high level of engineering and manufacturing technology, a prototype testing has been proposed. The prototype test will be carried out on 1:1 model in terms of dimension. However, the mass flow rate of the supercritical helium at 4.5 K and gaseous helium at 80 K will be on a 1:10 scale. The prototype cryoline has been designed and analyzed for thermal, structural and hydraulic parameters. The objective of this prototype test is to verify mechanical behavior due to thermal stress and pressure force, thermal and hydraulic performances. The concept of test facility has been realized along with the Piping and Instrumentation (P & I) diagram, instrumentation, controls, data acquisition,...

Thermal performance criterion of the TACB (Test Auxiliary Cold Box) dictates the need for an effective thermal shield between the ambient temperature at 300 K and the cold mass at 4 K, in line with the maximum heat load limitation of the cryoplant at 4 K temperature level. This thermal shield, to be forced flow cooled and maintained at 80 K temperature level will screen direct thermal conduction and radiation heat loads from the ambient to the cold mass. The design objective is to attain cool-down of the shield within a desired time frame with least possible cryogen mass flow rate and pressure drop across the thermalization channel while adhering to the allowable heat load limit at 80 K temperature level. In the present paper, a transient thermal analysis is carried out by varying the process conditions, i.e. pressure and mass flow rate of the cooling fluid to compare time dependent thermal characteristics of the shield during cool-down and decide the optimum flow parameters from the available range.

Safety is important in cryogenic field dealing with liquid or supercritical state helium. Cryolines carrying helium at 4 K temperature level and equipped with thermal compensation devices, like bellows, are prone todevelopment of cracksand its propagation after a number of expansion and contraction. Even after careful design, appropriate material selection and a strict quality control during manufacturing, probability of crack development in the Cryo-line cannot be avoided. An investigative study of failure of process pipe due to the development of crack has been carried out for a long Cryo-line laid in a confined space considering the space between two vacuum barriers is 10 meter. Study shows that minimum temperature of the Outer Vacuum Jacket (OVJ)goes down to 251 K in 540th second andthe minimum temperature of the confined space reaches to 73 K in 37th second. As the crack size reduces, the OVJ pipe temperature approaches to the minimum value in longer time and confined space final temperature increases.

System of Cryoline and Cryo-distribution for ITER has matured to a stage of preliminary design with the advent of industrial associates. Starting from the cold power source, the system of Cryoline and Cryo-distribution transfers the controlled cold power through a large network to the superconducting magnets and cryopumps. The functional responsibility also includes very high reliability and availability with respect to the operation of the ITER machine. Following the completion of conceptual design, it was necessary to perform a detailed engineering study of the complete network of distribution system in totality, before entering in to the industrial phase. This is to ensure the functional responsibility of the system. Value engineering in the area of distribution boxes including interfacing Cryolines has been performed in order to access the integrated reliable performance with respect to the overall cryogenic system, reducing the risk transferred to the industrial partners. These include technical risk assessment, analysis, mitigation plan and implementation with the industrial partners. The paper describes the methodology of technical risk management, value engineering performed to ensure fulfilment of licensing and regulatory obligations, functional reliability, testing and manufacturability by standard industrial processes, so that highly reliable integrated distribution system is delivered for the project.

Cold circulators, part of ITER Cryo-distribution system, have now reached to a stage of final qualification to demonstrate the design to cater the maximum mass flow and operational demands of the toroidal field (TF) superconducting magnet of ITER with a very high isentropic efficiency. The design for the two numbers of TF cold circulators are now complete gratifying additionally the operational requirements of poloidal field & central solenoid superconducting magnet as well as the cryopumps towards the fulfilment of standardization aspects. Management of physical and functional interfaces has been identified as one the most critical aspect towards the performance of cold circulator. All the interfaces of cold circulators have been analysed with the help of optimized interfacing parameters of Test Auxiliary Cold Box (TACB) and cryogenic test facility at JAEA, Japan during the course of design finalization. Testing at the warm conditions after completion of precise manufacturing of cold circulators has been performed before integrating into the TACB to fulfil the Japanese as well as European regulatory requirements simultaneously. The paper elaborates the methodology of interface management and control, analysis performed towards the interface management and preliminary test results towards the qualification test of the ITER cold circulator.

ITER cryolines (CLs) are complex network of vacuum-insulated multi and single process pipe lines, distributed in three different areas at ITER site. The CLs will support different operating loads during the machine life-time; either considered as nominal, occasional or exceptional. The major loads, which form the design basis are inertial, pressure, temperature, assembly, magnetic, snow, wind, enforced relative displacement and are put together in loads specification. Based on the defined load combinations, conceptual estimation of reaction loads have been carried out for the lines located inside the Tokamak building. Adequate numbers of embedded plates (EPs) per line have been defined and integrated in the building design. The finalization of building EPs to support the lines, before the detailed design, is one of the major design challenges as the usual logic of the design may alter. At the ITER project level, it was important to finalize EPs to allow adequate design and timely availability of the Tokamak building. The paper describes the single loads, load combinations considered in load specification and the approach for conceptual load estimation and selection of EPs for Toroidal Field (TF) Cryoline as an example by converting the load combinations in two main load categories; pressure and seismic.

We report the development of an Electron Multiplier Charge Coupled Device (EMCCD) based luminescence dating system. The system enables position sensitive measurements of luminescence for the estimation of spatially resolved distribution of equivalent dose for complex geological samples. The system includes: 1) a sample stimulation unit (with both thermal and optical stimulations), 2) an optics unit that comprises imaging optics and, 3) a data acquisition and processing unit. The system works in a LabVIEW environment with a graphical user interface (GUI). User specified stimulation protocols enable thermal and optical stimulation in any desired combination. The optics unit images the luminescence on to a EMCCD (512 × 512 pixels, each of 16μm × 16μm size) and maintains a unit magnification. This unit has flexible focusing and a filter housing that enables change of filters combinations without disturbing the setup. Time integrated EMCCD images of luminescence from the sample are acquired as a function of programmable dwell time and these images are processed using indigenously developed MATLAB based programs. Additionally, the programs align the acquired images using a set of control points (identifier features on the images) to a single pixel accuracy. The dose evaluation is based on integrated intensity from selected pixels followed by generation of a growth curve giving luminescence as a function of applied beta doses. Development of this EMCCD camera based luminescence system will enable in-situ luminescence measurements of the samples, without the requirement of separating mineral grains from their matrix. It will also allow age estimation of samples such as lithic artifacts/structures via dating of their surfaces, fusion crust of meteorites, pedogenic carbonates, etc and will additionally open up possibilities of application like testing spatial uniformity of doping in artificial luminescence phosphors, dating/dosimetry of inclusions etc.

Cryogenic Cold Circulating Pump (CCP) provides cryogenic cooling of superconducting magnets (SC) and cryopumps in fusion research reactors by forced flow circulation of supercritical helium (SHe) at desired pressure head during various operating modes. The existing operating CCPs for helium have comparatively very less capacity, of the order 1.2 kg/s, than the future requirements of the order of 3 kg/s. Actual performance of CCP deviates from the theoretical ideal performance due to various fluid-dynamic losses involved during the operation. Design of CCP may be improved by prediction of losses through performance analysis. The present work involves performance analysis of the cryogenic CCP with outline of its major geometric dimensions obtained through basic design. Various loss models and its contribution to the head versus flow (H-Q) characteristics curve at different operating speed of CCP, obtained from the MATLAB® program, shows the best operating point with respect to system characteristics.

Cold circulating pumps (CCP) in ITER-Cryodistribution system has been evaluated as the most technology critical component. Test Auxiliary Cold Box (TACB) is a valve box to perform the pre-series test of CCPs of ITER. The operating conditions of the CCPs installed in TACB during the test demands for detailed design of instrumentation and control system including physical and functional interfaces with subsystems of the test facility. Control system of TACB consists of a programmable logic controller (PLC) at the system level and two dedicated controllers for CCPs at component level, integrated together using various control and handshaking signals. Local Controllers at component level are capable of standalone local operation of respective CCPs. This paper describes the control system design using system level PLC, local controllers, associated network system, interface definition controller programming and data acquisition considering all the operating scenarios of the TACB during the pre-series test.

The torus & cryostat cryoline of ITER cryodistribution system has been designed as per the process specifications. The cryoline is an ensemble of six process pipes, thermal shield, fixed, sliding support and outer jacket. The fixed support (FS), which also acts as the anchor for the bellows, is one of the most important part of the cryoline. The FS has to withstand the static weight of pipes as well as the spring and thrust forces arising from the bellows. The FS design has been optimized for the thermal, structural and for combined loads with thermal optimization criteria; less than 8 Watt at 100 K and less than 1.5 Watt at 4.5 K. ANSYS 10.0 has been used for the analysis and CATIA V5 R16 has been used for the modelling as well as geometry optimization. In order to bring the Von-Mises stress within the acceptable limit of 115 MPa, a detailed mesh sensitivity study has been carried out along with design optimization. The iterative process of mesh refinement continued till stress convergence is achieved. The stress analysis has been carried out for optimized mesh size. The paper will present the design methodology, construction details and the results of the analysis.

Large and complicated network of cryo-lines are required for the ITER cryogenic system, connecting cryo-plant, cryo-distribution system and applications. Fixed support, sliding support and vacuum barrier are the integral part of the design of the cryo-lines. These supports, apart from the purpose of supporting the dead weight of internal process pipes, take care of different forces generated due to the thrust, spring and the thermal load. Therefore, stresses are generated on them. In order to have a measurement of the stress, experiments are done with strain gages mounted on these components. For the proto-type cryo-line of ITER, stress analysis has been carried out and the contours of stress on these components are available. The measurement with strain gages will be done to validate the design as well as to get the idea of the absolute values of the stresses expected to generate. The temperature zones will be in the range of 4.5 K to 80 K. Therefore, special strain gage and its measurement have been planned for this purpose. The paper will discuss mounting process of the strain gages, the basis of deciding the location of gages, measurement procedure with error compensation and correction as well as data acquisition techniques.

Objectives. TARGET randomised 376 children with persistent OME to 3 regimens: watchful waiting (WW), ventilation-tubes only (VTO), and ventilation tubes-adenoidectomy (VTA). At 2-year follow-up, the demonstrated greater benefits of VTA than VTO in terms of respiratory problems and hearing thresholds were still present. Records from the largest centre were examined to determine how long benefits of +adenoidectomy continue beyond 2 years. Methods. Retrospective records analyses of Leicester children captured consultations and treatments outside the TARGET protocol, plus pure-tone-average (0.5–4 kHz) at latest clinical entry. Results. Ninety-four of 95 notes (99%) were available, with time-lags of 7.5–11.6 years. On intention-to-treat analysis, children receiving treatment additional to allocation comprised 61% of WW, 59% of VTO, and 44% of VTA, with average surgical procedures numbering 1.0, 2.1, and 1.7. Proportions of children requiring >1 additional procedure were 13%, 34%, and 15%. Differences (VTO-VTA) for consultations, operations and combined were marginal for this single centre but consistent with the significant all-centre data for 3–6 years from randomisation. Mean latest pure-tone-averages were 15.84, 11.73, and 12.44 dBHL. Conclusions. (1) Additional adenoidectomy has enduring benefits over VTO, although most clinical benefit appears to arise in the early years. (2) The two fifths of children randomised to WW not requiring surgery merit detailed epidemiological characterisation. (3) The benefits of surgery in OME are modest, requiring large-number trials, but are genuine.

Supercritical helium cold circulators operating at unprecedented high mass flow rates are required to maintain the ITER magnet and cryopump system at operating conditions. The qualification test plan has been developed for the two cold circulators installed in the Test Auxiliary Cold Box in compliance with the Japan Atomic Energy Agency cryogenic test facility consisting of a cryoplant of ∼ 5 kW at 4.5 K. The process modelling for test modes such as cool-down/warm-up, nominal and 10% higher speed operation, including test approach, assumptions made, and expected results using the control strategies to be implemented during the test are described.