First results from the OSQAR photon regeneration experiment: No light shining through a wall

A new method to amplify the photon-axion conversions in magnetic field is proposed using a buffer gas at a specific pressure. As a first result, new bounds for mass and coupling constant for purely laboratory experiments aiming to detect any hypothetical scalars and pseudo-scalars which can couple to photons were obtained at 95% confidence level, excluding the PVLAS result newly disclaimed.Comment: 4 pages, 5 figure

First Results of the Full-Scale OSQAR Photon Regeneration Experiment

Recent intensive theoretical and experimental studies shed light on possible new physics beyond the standard model of particle physics, which can be probed with sub-eV energy experiments. In the second run of the OSQAR photon regeneration experiment, which looks for the conversion of photon to axion (or Axion-Like Particle), two spare superconducting dipole magnets of the Large Hadron Collider (LHC) have been used. In this paper we report on first results obtained from a light beam propagating in vacuum within the 9 T field of two LHC dipole magnets. No excess of events above the background was detected and the two-photon couplings of possible new scalar and pseudo-scalar particles could be constrained.Comment: 5 pages, 4 figures, Photon 2011 Conference, Submitted to JO

Mycoplasma gallisepticum infection in the grey partridge Perdix perdix: outbreak description, histopathology, biochemistry and antioxidant parameters

<p>Abstract</p> <p>Background</p> <p>The grey partridge is an important game bird in Europe that has declined considerably over the last decades. The production and release of farm-bred birds can be threatened by infectious agents. The objective of this study was to describe the outbreak, pathology, and blood and tissue biochemical responses in a flock of grey partridges naturally infected with <it>Mycoplasma gallisepticum</it>.</p> <p>Results</p> <p>Morbidity and mortality rates were 100% and 60%, respectively. Necropsy revealed an accumulation of caseous exudate within the infraorbital sinuses, tracheitis, pneumonia and airsacculitis. There were significant increases in activities of lactate dehydrogenase, creatine kinase and amylase, and levels of total protein and glucose in <it>Mycoplasma</it>-infected birds when compared to control. Catalase showed significantly lower activity in the heart, lungs, liver and gonads of <it>Mycoplasma</it>-infected birds. Glutathione-S-transferase activity was elevated in the eye and the associated infraorbital sinus and kidneys, and decreased in the liver. Decreased levels of reduced glutathione were found in the heart, kidneys, liver and gonads. The activity of glutathione reductase was lower only in the lungs. Compared to healthy birds, mycoplasmosis in the grey partridge caused significant differences in the level of lipid peroxidation in lungs and plasma (p < 0.05), while the ferric reducing antioxidant power was lower in the heart and kidneys (p < 0.01). Significant correlations among responses of the antioxidant parameters were found namely in the heart, lungs, spleen, liver and plasma. There were also numerous significant inter-tissue correlations of all the studied antioxidant parameters.</p> <p>Conclusions</p> <p>The present study demonstrates the high susceptibility of grey partridges to natural infection by <it>M. gallisepticum</it>, the severity of the disease based on histopathology, and the modulation of blood chemical profiles and oxidative stress-associated parameters in the avian hosts, thus enhancing the understanding of the pathogenesis of mycoplasmosis in birds. Moreover, the reported reference values can be useful for the evaluation of the state of health in grey partridges.</p

Axion Search by Laser-based Experiment OSQAR

International audienceLaser-based experimentOSQAR in CERN is aimed to the search of the axions by twomethods. The photon regeneration experiment is using two LHC dipole magnets of the length 14.3 m and magnetic field 9.5 T equipped with an optical barrier at the end of the first magnet. It looks as light shining through the wall. No excess of events above the background was detected at this arrangement. Nevertheless, this result extends the exclusion region for the axion mass. The second method wants to measure the ultra-fine Vacuum Magnetic Birefringence for the first time. An optical scheme with electro-optical modulator has been proposed, validated and subsequently improved. Cotton-Mouton constant for air was determined in this experiment setup

Progress of the Laser-based Experiment OSQAR

International audienceOSQAR experiment at CERN is based on two laser methods for search of axions and scalar particles. The light shining through the wall experiment has been using two LHC dipole magnets with an optical barrier, argon laser, and cooled 2D CCD detector for the measuring of expected regenerated photons. The second method wants to measure the Vacuum Magnetic Birefringence. An optical set-up with electro-optical modulator has been proposed, validated and subsequently improved in collaborating institutes. Cotton-Muton effect in nitrogen was measured by this method. Prototype of a one-meter long laser cavity was developed for this experiment

Carbon carrying capacity in primary forests shows potential for mitigation achieving the European Green Deal 2030 target

13 Pág.Carbon accounting in the land sector requires a reference level from which to calculate past losses of carbon and potential for gains using a stock-based target. Carbon carrying capacity represented by the carbon stock in primary forests is an ecologically-based reference level that allows estimation of the mitigation potential derived from protecting and restoring forests to increase their carbon stocks. Here we measured and collated tree inventory data at primary forest sites including from research studies, literature and forest inventories (7982 sites, 288,262 trees, 27 countries) across boreal, temperate, and subtropical Global Ecological Zones within Europe. We calculated total biomass carbon stock per hectare (above- and below-ground, dead biomass) and found it was 1.6 times larger on average than modelled global maps for primary forests and 2.3 times for all forests. Large trees (diameter greater than 60 cm) accounted for 50% of biomass and are important carbon reservoirs. Carbon stock foregone by harvesting of 12–52% demonstrated the mitigation potential. Estimated carbon gain by protecting, restoring and ongoing growth of existing forests equated to 309 megatons carbon dioxide equivalents per year, additional to, and higher than, the current forest sink, and comparable to the Green Deal 2030 target for carbon dioxide removals.We thank the many people involved with the collection and provision of the site data and recognise the significant resources, people and time required to collect this invaluable data. The research for the synthesis, analysis and writing (H.K., Z.K., S.H., B.M.) was supported by a grant from a charitable organisation which neither seeks nor permits publicity for its efforts. The funder had no involvement in the study design, results or publication of the paper. Site data from Spain was funded by the Spanish Ministry of Science, Innovation and Universities [AGL2016-76769-C2-2-R]. C.P.C. was supported by the Spanish Ministry of Science and Innovation [RYC2018-024939-I]. J.A.M.V. was supported by the Ramón Areces Foundation Grants for Postdoctoral Studies. Contribution of D.A., K.K. and P.S. as well as data collection and processing from Czech natural forests was supported by Czech Science Foundation, project no. 24-11119S. D.M.-B. was funded by projects AGL2015-73190-JIN, PID2019-110273RB-I00 and contract RYC-2017-23389 by the Spanish Ministry of Science and Innovation MCIN/AEI. V.B. and I.D. were supported by the FORCLIMIT project funded in the frame of the ERA-NET FACCE ERA-GAS and with national support from Romanian National Authority for Scientific Research and Innovation, CCCDI \u2013 UEFISCDI [grant number 82/2017]. FACCE ERA-GAS has received funding from the European Union\u2019s Horizon 2020 research and innovation programme [grant agreement 696356. T.Z. was funded by The WWF Bulgaria through the project IKEA \u2116 9E0710.05 and by The National Roadmap for Research Infrastructure (2020-2027), Ministry of Education and Science of Republic of Bulgaria, through agreements No DO1-405/18.12.2020 and DO1-163/28.07.2022 (LTER-BG). L.D. was funded by the project of the National Research, Development and Innovation Office NKFIH K 131837. T.N. received support from the Slovenian Research Agency (Project No. J4-1765). For additional assistance with site data, we thank Dr. Ra\u00FAl Sanchez-Salguero and Dr. Andrea Hevia for evaluating the age in the dendrochronological samples in Spain, and Nesibe K\u00F6se, Mehmet Do\u011Fan, Daniel Bishop, Marco Mina, Timothy Thrippleton, Neil Pederson, Guillermo Gea-Izquierdo and Macarena F\u00E9rriz for their help during fieldwork, and Cengiz Cihan and the Turkish General Directorate of Forestry (OGM) in Bor\u00E7ka (Artvin) for their assistance in the field in Turkey.Peer reviewe