15 research outputs found
Effect of harvest time on seed oil and protein contents and compositions in the oleaginous gourd Lagenaria siceria (Molina) Standl
BACKGROUND: The stage of fruit ripeness at the time of harvest determines the final quality of ripe fruit. In this study, changes in the chemical composition of seed kernels from the oleaginous gourd Lagenaria siceraria (Molina) Standl. during maturation were evaluated to determine the best time to harvest the berries. Two cultivars (round and oval berry) were studied at three maturation stages (30 and 50 days after fruit set (DAFS) and complete plant whiteness (CPW))
Quantitative determination of through-coating porosity in thin ceramic physically vapour-deposited coatings
An experimental method is proposed to determine in a quantitative way the through-coating porosity of thin ceramic coatings deposited on metallic substrates. The method is based on a coulometric measurement performed during potentiodynamic polarization of a coated sample. Since coating and substrate materials may interact electrochemically, a standard addition procedure to derive the porosity index has been worked out. The porosity of different TiN-based physically vapour-deposited coatings has been compared. The porosity values obtained are more realistic in comparison with those obtained by other methods.status: publishe
Learning Aircraft Behavior from Real Air Traffic
International audienceWhat if we could observe the real world to teach our simulation how to work? There would be no need for physics computation, no need to describe what kind of entities exists in the world. Everything would be observed, learned and made usable for simulation. This is the goal of EVAA
The Leir RF System
The lead-lead physics program of LHC relies on major changes of the CERN ion injector chain. In this framework, the conversion of LEAR (low energy antiproton ring) into the Low Energy Ion Ring (LEIR) is central and implies a new accelerating system covering a wide frequency range (0.35 - 5 MHz) with a moderate voltage (4 kV). For this purpose two new wide-bandwidth cavities, loaded with Finemet® magnetic alloy cores, have been built in collaboration with KEK. Two 60 kW RF power amplifiers have also been built and the RF systems are now installed in the LEIR ring. They individually cover the whole frequency range without tuning and allow multi-harmonic operation. The design has been guided by need of safety margins, reliability and ease of maintenance. Some design aspects are presented as well as the performance achieved. The lead-lead physics program of LHC relies on major changes of the CERN ion injector chain. In this framework, the conversion of LEAR (low energy antiproton ring) into the Low Energy Ion Ring (LEIR) is central and implies a new accelerating system covering a wide frequency range (0.35 - 5 MHz,) with a moderate voltage (4 kV). For this purpose two new wide-bandwidth cavities, loaded with Finemet® magnetic alloy cores, have been built in collaboration with KEK. Two 60 kW RF power amplifiers have also been built and the RF systems are now installed in the LEIR ring. They individually cover the whole frequency range without tuning and allow multi-harmonic operation. The design has been guided by need of safety margins, reliability and ease of maintenance. Some design aspects are presented as well as the performance achieved
Oral as compared to intravenous tranexamic acid to limit peri-operative blood loss associated with primary total hip arthroplasty: A randomised noninferiority trial.
peer reviewed[en] BACKGROUND: Oral as compared to intravenous tranexamic acid (TXA) is an attractive option, in terms of cost and safety, to reduce blood loss and transfusion in total hip arthroplasty. Exclusion criteria applied in the most recent randomised trials may have limited the generalisability of oral tranexamic acid in this indication. Larger and more inclusive studies are needed to definitively establish oral administration as a credible alternative to intravenous administration.
OBJECTIVES: To assess the noninferiority of oral to intravenous TXA at reducing intra-operative and postoperative total blood loss (TBL) in primary posterolateral approached total hip arthroplasty (PLTHA).
DESIGN: Noninferiority, single centre, randomised, double-blind controlled study.
SETTING: Patients scheduled for primary PLTHA. Data acquisition occurred between May 2021 and November 2022 at the University Hospital of Liège, Belgium.
PATIENTS: Two hundred and twenty-eight patients, randomised in a 1 : 1 ratio from a computer-generated list, completed the trial.
INTERVENTIONS: Administration of 2 g of oral TXA 2 h before total hip arthroplasty and 4 h after incision (Group oral) was compared to the intravenous administration of 1 g of TXA 30 min before surgery and 4 h after incision (Group i.v.).
MAIN OUTCOME MEASURES: TBL (measured intra-operative and drainage blood loss up to 48 h after surgery, primary outcome), decrease in haemoglobin concentration, D-Dimer at day 1 and day 3, transfusion rate (secondary outcomes).
RESULTS: Analyses were performed on 108 out of 114 participants (Group i.v.) and 104 out of 114 participants (Group oral). Group oral was noninferior to Group i.v. with regard to TBL, with a difference between medians (95% CI) of 35 ml (-103.77 to 33.77) within the noninferiority margins. Median [IQR] of estimated TBL was 480 ml [350 to 565] and 445 ml [323 to 558], respectively. No significant interaction between group and time was observed regarding the evolution of TBL and haemoglobin over time.
CONCLUSIONS: TXA as an oral premedication before PLTHA is noninferior to its intravenous administration regarding peri-operative TBL.
TRIAL REGISTRATION: European Clinical Trial Register under EudraCT-number 2020-004167-29 (https://www.clinicaltrialsregister.eu/ctr-search/trial/2020-004167-29/BE)
Degradation and Recovery of the LHC RF Cryomodule Performance Using the Helium Processing Technique
The LHC RF cryomodule "Asia" suffered an accidental influx of about 0.5 l of tunnel air during the leak checks of the pumping manifolds. The resulting risk of particle contamination was difficult to assess, and could not be excluded with certainty. If one or more cavities were contaminated, a severe impact on beam operations in the LHC machine was to be expected. In order to minimize the risks, the Asia cryomodule has been replaced with a spare unit. Subsequently, the cryomodule was tested in the SM18 test facility without intermediate venting, and showed high levels of radiation due to field emission above 1.8 MV in one of the cavities. The other cavities were less strongly affected, but clear signs of contamination were observed. The helium processing technique was used to improve the performance of the SRF cavity with respect to field emission. This paper will discuss the results of the above-mentioned test
CERN’s bulk niobium high gradient SRF programme: developments and recent cold test results
Recent results from the bulk niobium high-gradient cavity development program at CERN are presented, with particular focus on test results for the 704 MHz bulk niobium 5-cell elliptical cavity prototypes produced for the Superconducting Proton Linac (SPL) project. Successive cold tests of bare cavities have been used to refine the cavity preparation and testing process, with all steps done in-house at CERN. Current performance results are discussed with reference to observables such as ambient magnetic field, field emission levels, and quenches
Diagnostic developments at CERN’s SRF testing facility
As part of CERN’s re-establishment of an SRF cold testing facility for bulk niobium cavities, diagnostic instrumentation and testing procedures on our vertical cryostat have been upgraded, with particular attention given to quench location, ambient magnetic field control, thermometry and thermal cycling techniques. In addition, preparation and measurement procedures have been addressed, allowing for improved measurement of cavity properties and detailed study of transient effects during the course of cavity testing
Successful RF and Cryogenic Tests of the SOLEIL Cryomodule
In the Storage Ring (SR) of the Synchrotron SOLEIL light source, two cryomodules will provide the maximum power of 600 kW required at the nominal energy of 2.75 GeV with the full beam current of 500 mA and all the insertion devices. A cryomodule prototype, housing two 352 MHz superconducting single-cell cavities with strong damping of the Higher Order Modes has been built and successfully tested in the ESRF. Even though the achieved performance (3 MV and 380 kW) does meet the SOLEIL requirement for the first year of operation, it was decided to upgrade the cryomodule prototype before its implementation in the SR. Modifications of the internal cryogenic system as well as the input power and dipolar HOM couplers required complete disassembling, reassembling and testing of the cryomodule, which were carried out at CERN. This refurbishment program, which was achieved in the framework of a collaboration between SOLEIL, CEA and CERN, is reported in this paper. A second cryomodule, similar to the modified prototype, is under manufacturing and will be implemented in the SR by the end of 2006