Accurate modelling of small-scale linear ion trap operating mode using He buffer gas to improve sensitivity and resolution for in-the-field mass spectrometry

Improved sensitivity and resolution of a small-scale linear ion trap is observed using He buffer.</p

Analysis of chlorinated hydrocarbons in gas phase using a portable membrane inlet mass spectrometer

A compact portable membrane inlet mass spectrometer (MIMS) has been used for the first time to detect and monitor, both qualitatively and quantitatively, volatile chlorinated hydrocarbons in the gaseous phase.</p

Direct analysis and monitoring of organosulphur compounds in the gaseous phase using portable mass spectrometry

Organosulphides are ubiquitous in the natural world and are important in the agriculture, pharmaceuticals and petrochemical sectors.</p

Body Composition and Somatotype in Elite Handball Players

As the main objective, this research work had to compare pre and post complex training effects on body composition in elite handball players in the Spanish 2nd Division. Eleven players were included in the study. Six of them formed an experimental group, and 5 of them the control group. They have undergone the complex training session which was done once a week. The following parameters were analyzed: BMI (Body Mass Index), somatotype, FM (Fat Mass), MM (Muscle mass), RM (Residual Mass), WHR (Waist to Hip Ratio), BM (Bone Mass). The results have shown that there was a not statistically significant difference after the 6 – week program neither in body composition and somatotypes. Since this program did not have a big influence on body composition we could say that complex training influences body composition should be further researched

Optimised quadrupole mass spectrometer with a dual filter analyser for in-field chemical sniffing of volatile organic compounds

We report a novel portable 17 kg system based on a quadrupole mass spectrometer (QMS) with an electronic power consumption of 24 W. The system can be used for the in-field identification of gases and volatile/semivolatile organic compounds (VOCs/SVOCs). The mass analyser is a custom-made quadrupole mass filter with a Brubaker pre-filter that gives a mass range of m/z 1-500. It is an upgrade of the previous m/z 1-200 range triple filter analyser system. Analyser design was optimized using 3D numerical simulations as a performance trade-off between single and triple filter designs while maintaining high sensitivity and ease of integration. This also required enhanced design of the electronic control unit (ECU) compared to the previous triple filter ECU designs with lower power consumption, size, weight and cost of the overall system. Another major ECU improvement includes high stability of DC voltage control and ultra-low RF drift, which is important for in-field applications that require stable mass peaks for reliable quantitative analysis and continuous monitoring. Experimental results are presented for the perfluorotributylamine (PFTBA) calibrant and acetone to assess the functionality of the instrument. Performance comparison between the dual and triple filter quadrupole analysers has also been done. Mass spectra are given for methyl benzoate (cocaine simulant), piperidine (phencyclidine simulant), cyclohexanone (C4 simulant) and 2-nitrotoluene (TNT simulant) to assess potential capability for the identification of threat compounds. All spectral results show good correlation with the NIST library mass spectra with unit resolution obtained for spectral peaks within a m/z 1-400 mass range

Mobile mass spectrometry for water quality monitoring of organic species present in nuclear waste ponds

This work uses a portable mass spectrometer (MS) for lab-based water quality monitoring of organic compounds, which are present in highly toxic nuclear waste ponds.</p

EphrinB2/EphB4 signaling regulates non-sprouting angiogenesis by VEGF

Vascular endothelial growth factor (VEGF) is the master regulator of angiogenesis, whose best-understood mechanism is sprouting. However, therapeutic VEGF delivery to ischemic muscle induces angiogenesis by the alternative process of intussusception, or vascular splitting, whose molecular regulation is essentially unknown. Here, we identify ephrinB2/EphB4 signaling as a key regulator of intussusceptive angiogenesis and its outcome under therapeutically relevant conditions. EphB4 signaling fine-tunes the degree of endothelial proliferation induced by specific VEGF doses during the initial stage of circumferential enlargement of vessels, thereby limiting their size and subsequently enabling successful splitting into normal capillary networks. Mechanistically, EphB4 neither inhibits VEGF-R2 activation by VEGF nor its internalization, but it modulates VEGF-R2 downstream signaling through phospho-ERK1/2.; In vivo; inhibitor experiments show that ERK1/2 activity is required for EphB4 regulation of VEGF-induced intussusceptive angiogenesis. Lastly, after clinically relevant VEGF gene delivery with adenoviral vectors, pharmacological stimulation of EphB4 normalizes dysfunctional vascular growth in both normoxic and ischemic muscle. These results identify EphB4 as a druggable target to modulate the outcome of VEGF gene delivery and support further investigation of its therapeutic potential

Analysis of Fission Gas Release Kinetics by On-Line Mass Spectrometry

International audienc

Analysis of Fission Gas Release Kinetics by On-Line Mass Spectrometry

Abstract-The release of fission gases (Xe and Kr) and helium out of nuclear fuel materials in normal operation of a nuclear power reactor can constitute a serious limitation of the fuel lifetime. Moreover, radioactive isotopes of Xe and Kr contribute significantly to the global radiological source term released in the primary coolant circuit in case of accidental situations accompanied by loss of fuel rod integrity. As a consequence, fission gas release investigation is of prime importance for the nuclear fuel cycle economy, and is the driving force for numerous R&amp;D programs. In this domain, for understanding current fuel behavior issues, preparing the development of new fuels (e.g., for Gen IV power systems) and for improving modeling prediction capability, there is a marked need for innovations in the instrumentation field, mainly for: • Quantification of very low fission gas concentrations, released from fuel sample and routed in sweeping lines, • Monitoring of quick gas release variations by quantification of elementary release during a short period of time, • Detection of a large range of atomic masses (e.g., H 2 , HT, He, CO, CO 2 , Ne, Ar, Kr, Xe), together with separation of isotopes for Xe and Kr elements, • Coupled measurement of stable and radioactive gas isotopes, by using mass spectrometry and gamma spectrometry techniques in parallel. To fulfill these challenging needs, a common strategy for analysis equipment implementation has been set up thanks to a recently launched collaboration between the CEA and the University of Provence, with the support of the Liverpool University. It aims at developing a chronological series of mass spectrometer devices based upon quadrupole mass filters and 2D/3D ion traps with Fourier transform operating mode. These devices have superior performance to match the previous challenges for out-of-pile and in-pile experiments. The final objective is to install a high performance on-line mass spectrometer coupled to a gamma spectrometer in the fission product laboratory of the future Jules Horowitz Material Test Reactor. An intermediate step will consist of testing prototype equipment on an existing experimental facility in the LECA-STAR Hot Cell Laboratory of the CEA Cadarache. This paper presents the scientific and operational risks linked to fission gas issues and summarizes the current state of art for analyzing them in nuclear facilities. It details the skills gathered through this collaboration and the development approach of the mass spectrometer set-up to overcome technological problems. Finally the paper describes a proposed implementation strategy for the nuclear research facilities of CEA Cadarache. Index Terms-2D/3D ion trap mass spectrometry, in-pile and out-of-pile fission gas release kinetics measurement, material testing reactor, multiphoton ionization, on-line mass filter