A small scale remote cooling system for a superconducting cyclotron magnet

Through a technology transfer program CERN is involved in the R&D of a compact superconducting cyclotron for future clinical radioisotope production, a project led by the Spanish research institute CIEMAT. For the remote cooling of the LTc superconducting magnet operating at 4.5 K, CERN has designed a small scale refrigeration system, the Cryogenic Supply System (CSS). This refrigeration system consists of a commercial two-stage 1.5 W @ 4.2 K GM cryocooler and a separate forced flow circuit. The forced flow circuit extracts the cooling power of the first and the second stage cold tips, respectively. Both units are installed in a common vacuum vessel and, at the final configuration, a low loss transfer line will provide the link to the magnet cryostat for the cooling of the thermal shield with helium at 40 K and the two superconducting coils with two-phase helium at 4.5 K. Currently the CSS is in the testing phase at CERN in stand-alone mode without the magnet and the transfer line. We have added a "validation unit" housed in the vacuum vessel of the CSS representing the thermo-hydraulic part of the cyclotron magnet. It is equipped with electrical heaters which allow the simulation of the thermal loads of the magnet cryostat. A cooling power of 1.4 W at 4.5 K and 25 W at the thermal shield temperature level has been measured. The data produced confirm the design principle of the CSS which could be validated

EVALUATING THE ENERGY DEMANDS OF EXERCISING WITH A NEW TYPE OF WHOLE BODY EXERCISE EQUIPMENT

Whole body exercise has been repeatedly described as an effective tool for enhancing cardio-respiratory (CRV) function, preventing CRV disease, and improving performance of activities of daily living. PURPOSE: This study sought to better understand the energetic demands of using a new whole body type of exercise equipment (PMXT) that emphasizes independent use of both upper and lower limbs. The PMXT was compared directly with an elliptical exercise machine (EEM) by evaluating both aerobic and anaerobic energy expenditure (EE) contributions. METHODS: 12 physically active adults (6 men + 6 women (Mean±SD) 36±12 yrs, 22.7±2.6 kg/m2) each completed easy and moderate intensity 3-min submaximal stages using both the PMXT and the EEM, as well as 4 mins of structured PMXT intervals to exhaustion (5 total test stages). Subjects wore a portable metabolic measurement system to assess Aerobic EE (kcals/min). Fingertip blood lactate (BL) was collected at the end of each stage to determine Anaerobic EE (kcals/min), which was calculated from each BL measurement using a standard conversion of 3.0 ml/kg/min/1.0 mmol BL. Total EE, calculated as Aerobic EE + Anaerobic EE, was then determined for each testing stage. Values for Aerobic and Total EE were then compared using a 1-factor (Stages) RM ANOVA and Sheffe\u27s post hoc test (α = 0.05). RESULTS: Aerobic EE was highest for the PMXT intervals (14.0±1.3 kcals/min; P\u3c0.05), but similar between the PMXT and EEM for both easy (8.6±0.5 vs 8.6±0.7 kcals/min) and moderate intensity (10.8±0.7 vs 11.3±1.0 kcals/min) 3-min stages. All Aerobic EE values were equivalent to 6.7-10.8 METs, which are all considered vigorous intensities. Total EE for PMXT intervals (25.3±1.6 kcals/min) and the moderate intensity PMXT stage (17.2±1.2 kcals/min) differed statistically from all other stages (P\u3c0.05), while the other stages were statistically similar (10.8-13.4 kcals/min; P\u3e0.05). Thus, Anaerobic EE caused a 20-24% increase in Total EE for the submaximal EEM stages, a 40-53% increase for the PMXT stages, and an 81% increase for the PMXT intervals. CONCLUSIONS: When comparing a standard elliptical machine (EEM) to the new equipment (PMXT), the PMXT elicited significantly higher Total EE during highest intensity exercise bouts, but similar Aerobic EE during the submaximal bouts. Thus, the PMXT requires high aerobic and anaerobic EE demands when compared with the EEM. Further research should compare the PMXT to other types of fitness equipment (e.g., rowing machines, stair climber) to broadly compare the EE demands of the PMXT to a variety of fitness training devices

A small scale remote cooling system for a superconducting cyclotron magnet

Through a technology transfer program CERN is involved in the R&D; of a compact superconducting cyclotron for future clinical radioisotope production, a project led by the Spanish research institute CIEMAT. For the remote cooling of the LTc superconducting magnet operating at 4.5 K, CERN has designed a small scale refrigeration system, the Cryogenic Supply System (CSS). This refrigeration system consists of a commercial two-stage 1.5 W @ 4.2 K GM cryocooler and a separate forced flow circuit. The forced flow circuit extracts the cooling power of the first and the second stage cold tips, respectively. Both units are installed in a common vacuum vessel and, at the final configuration, a low loss transfer line will provide the link to the magnet cryostat for the cooling of the thermal shield with helium at 40 K and the two superconducting coils with two-phase helium at 4.5 K. Currently the CSS is in the testing phase at CERN in stand-alone mode without the magnet and the transfer line. We have added a "validation unit" housed in the vacuum vessel of the CSS representing the thermo-hydraulic part of the cyclotron magnet. It is equipped with electrical heaters which allow the simulation of the thermal loads of the magnet cryostat. A cooling power of 1.4 W at 4.5 K and 25 W at the thermal shield temperature level has been measured. The data produced confirm the design principle of the CSS which could be validated