28 research outputs found
Nuclear charge radii of molybdenum fission fragments
AbstractRadioisotopes of molybdenum have been studied using laser spectroscopy techniques at the IGISOL facility, University of JyvĂ€skylĂ€. Differences in nuclear charge radii have been determined for neutron deficient isotopes 90,91Mo and neutron rich isotopes 102â106,108Mo (and all stable isotopes). A smooth transition in the mean square charge radii is observed as the neutron number increases with no sudden shape change observed in the region around N=60. As N increases, the nuclear deformation appears to go beyond a maximum and a fall off at N=66 is observed. The magnetic moments of the odd isotopes 91,103,105Mo are also determined
New high-sensitivity searches for neutrons converting into antineutrons and/or sterile neutrons at the HIBEAM/NNBAR experiment at the European Spallation Source
The violation of baryon number, B, is an essential ingredient for the preferential creation of matter over antimatter needed to account for the observed baryon asymmetry in the Universe. However, such a process has yet to be experimentally observed. The HIBEAM/NNBAR program is a proposed two-stage experiment at the European Spallation Source to search for baryon number violation. The program will include high-sensitivity searches for processes that violate baryon number by one or two units: free neutron-antineutron oscillation (n -> (n) over bar) via mixing, neutron-antineutron oscillation via regeneration from a sterile neutron state (n -> [n',(n) over bar'] -> (n) over bar), and neutron disappearance (n -> n'); the effective Delta B = 0 process of neutron regeneration (n ->[n',(n) over bar'] -> n) is also possible. The program can be used to discover and characterize mixing in the neutron, antineutron and sterile neutron sectors. The experiment addresses topical open questions such as the origins of baryogenesis and the nature of dark matter, and is sensitive to scales of new physics substantially in excess of those available at colliders. A goal of the program is to open a discovery window to neutron conversion probabilities (sensitivities) by up to three orders of magnitude compared with previous searches. The opportunity to make such a leap in sensitivity tests should not be squandered. The experiment pulls together a diverse international team of physicists from the particle (collider and low energy) and nuclear physics communities, while also including specialists in neutronics and magnetics.Peer reviewe
Gaia Early Data Release 3 Summary of the contents and survey properties
Context. We present the early installment of the third Gaia data release, Gaia EDR3, consisting of astrometry and photometry for 1.8 billion sources brighter than magnitude 21, complemented with the list of radial velocities from Gaia DR2.
Aims. A summary of the contents of Gaia EDR3 is presented, accompanied by a discussion on the differences with respect to Gaia DR2 and an overview of the main limitations which are present in the survey. Recommendations are made on the responsible use of Gaia EDR3 results.
Methods. The raw data collected with the Gaia instruments during the first 34 months of the mission have been processed by the Gaia Data Processing and Analysis Consortium and turned into this early third data release, which represents a major advance with respect to Gaia DR2 in terms of astrometric and photometric precision, accuracy, and homogeneity. Results. Gaia EDR3 contains celestial positions and the apparent brightness in G for approximately 1.8 billion sources. For 1.5 billion of those sources, parallaxes, proper motions, and the (GBP â GRP) colour are also available. The passbands for G, GBP, and GRP are provided as part of the release. For ease of use, the 7 million radial velocities from Gaia DR2 are included in this release, after the removal of a small number of spurious values. New radial velocities will appear as part of Gaia DR3. Finally, Gaia EDR3 represents an updated materialisation of the celestial reference frame (CRF) in the optical, the Gaia-CRF3, which is based solely on extragalactic sources. The creation of the source list for Gaia EDR3 includes enhancements that make it more robust with respect to high proper motion stars, and the disturbing effects of spurious and partially resolved sources. The source list is largely the same as that for Gaia DR2, but it does feature new sources and there are some notable changes. The source list will not change for Gaia DR3.
Conclusions. Gaia EDR3 represents a significant advance over Gaia DR2, with parallax precisions increased by 30 per cent, proper motion precisions increased by a factor of 2, and the systematic errors in the astrometry suppressed by 30â40% for the parallaxes and by a factor ~2.5 for the proper motions. The photometry also features increased precision, but above all much better homogeneity across colour, magnitude, and celestial position. A single passband for G, GBP, and GRP is valid over the entire magnitude and colour range, with no systematics above the 1% leve
International collaboration in mass disasters involving foreign nationals within the EU : medico-legal investigations of Finnish victims of the Milan Linate airport SAS SK 686 aircraft accident on 8 October 2001
Identification of and investigation into the cause of death of foreign nationals in mass disasters are generally conducted according to the jurisdiction of the country in which the disaster occurs. However, such identification can be achieved only through co-operation with the authorities of the victims' countries of residence. On October 8th 2001 at Linate airport in Milan, Italy, an MD87 SAS airplane with 110 crew members and passengers on board collided on the ground with a Cessna Citation II jet with 2 pilots and 2 passengers. The plane then caught fire after having crashed into an airport baggage hangar causing the death of 4 other victims among the groundstaff. The accident claimed a total of 118 victims of 9 nationalities. Based on our experience from investigation of the Finnish victims, we explore how current national legislations of the EU member states and varying compliance with existing recommendations may influence the medico-legal investigation of a mass disaster. Legislative measures and further harmonisation of medico-legal procedures in connection with mass disasters within the EU are needed
Upregulation of inflammatory genes in the nasal mucosa of patients undergoing endonasal dacryocystorhinostomy
Elina Penttilä,1 Juha MT Hyttinen,2 Maria Hytti,2 Anu Kauppinen,2,3 Grigori Smirnov,1,4 Henri Tuomilehto,1,4 Juha Seppä,1 Juhani Nuutinen,1 Kai Kaarniranta2,31Department of Otorhinolaryngology, Kuopio University Hospital, and Institute of Clinical Medicine, University of Eastern Finland, 2Department of Ophthalmology, Institute of Clinical Medicine, University of Eastern Finland, 3Department of Ophthalmology, Kuopio University Hospital, 4Oivauni Sleep Clinic, Kuopio, FinlandBackground: Epiphora is a common complaint of nasolacrimal duct obstruction (NLDO) in adults. The precise pathogenesis of NLDO is still unknown, but inflammatory processes are believed to be predisposing factors. Endoscopic dacryocystorhinostomy (EN-DCR) is an effective surgical technique for treating symptomatic NLDO. The purpose of the procedure is to relieve the patient's symptoms by creating an opening, ie, a rhinostoma, between the lacrimal sac and the nasal cavity. Although the success rates after EN-DCR are high, the procedure sometimes fails due to onset of a fibrotic process at the rhinostomy site. The aim of this prospective comparative study was to investigate inflammation-related gene expression in the nasal mucosa at the rhinostomy site.Methods: Ten participants were consecutively recruited from eligible adult patients who underwent primary powered EN-DCR (five patients) or septoplasty (five controls). Nasal mucosa specimens were taken from the rhinostomy site at the beginning of surgery for analysis of gene expression. Specimens were taken from the same site on the lateral nasal wall for controls. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was performed for the inflammatory genes interleukin (IL)-6, IL-1ß, and CCL2, and because of a clear trend of increased inflammation in the EN-DCR samples, a wider PCR array was performed to compare inflammation-related gene expression in EN-DCR subjects and corresponding controls.Results: Our qRT-PCR results revealed a clear trend of increased transcription of IL-6, IL-1ß, and CCL2 (P=0.03). The same trend was also evident in the PCR array, which additionally revealed notable differences between EN-DCR subjects and controls with regard to expression of several other inflammation-related mediators. At 6-month follow-up, the success rate after primary EN-DCR was 60%, ie, in three of five patients.Conclusion: The present study demonstrates that there is an intense inflammation gene expression response in the nasal mucosa of patients undergoing EN-DCR.Keywords: epiphora, fibrosis, dacryocystorhinostomy, gene expression, inflammation, nasolacrimal duct obstructio
Lack of aldose 1-epimerase in Hypocrea jecorina (anamorph Trichoderma reesei): A key to cellulase gene expression on lactose
The heterodisaccharide lactose (1,4-O-ÎČ-d-galactopyranosyl-d-glucose) induces cellulase formation in the ascomycete Hypocrea jecorina (= Trichoderma reesei). Lactose assimilation is slow, and the assimilation of its ÎČ-d-galactose moiety depends mainly on the operation of a recently described reductive pathway and depends less on the Leloir pathway, which accepts only α-d-galactose. We therefore reasoned whether galactomutarotase [aldose 1-epimerase (AEP)] activity might limit lactose assimilation and thus influence cellulase formation. We identified three putative AEP-encoding genes (aep1, aep2, aep3) in H. jecorina, of which two encoded intracellular protein (AEP1 and AEP2) and one encoded an extracellular protein (AEP3). Although all three were transcribed, only the aep3 transcript was detected on lactose. However, no mutarotase activity was detected in the mycelia, their cell walls, or the extracellular medium during growth on lactose. Therefore, the effect of galactomutarotase activity on lactose assimilation was studied with H. jecorina strains expressing the C-terminal galactose mutarotase part of the Saccharomyces cerevisiae Gal10. These strains showed increased growth on lactose in a gene copy number-dependent manner, although their formation of extracellular ÎČ-galactosidase activity and transcription of the genes encoding the first steps in the Leloir and the reductive pathway was similar to the parental strain QM9414. Cellulase gene transcription on lactose dramatically decreased in these strains, but remained unaffected during growth on cellulose. Our data show that cellulase induction in H. jecorina by lactose requires the ÎČ-anomer of d-galactose and reveal the lack of mutarotase activity during growth on lactose as an important key for cellulase formation on this sugar
CD4(+) T cells mediate antibody-independent acquired immunity to pneumococcal colonization
Acquired immunity to Streptococcus pneumoniae (pneumococcus) has long been assumed to depend on the presence of anticapsular antibodies. We found, however, that colonization with live pneumococci of serotypes 6B, 7F, or 14 protected mice against recolonization by any of the serotypes and that protection from acquisition of a heterologous or homologous strain did not depend on anticapsular antibody. Further, intranasal immunization by live pneumococcal colonization or by a killed, nonencapsulated whole-cell vaccine protected antibody-deficient mice against colonization, suggesting independence of antibodies to any pneumococcal antigens. Protection by intranasal immunization with whole-cell vaccine was completely abrogated in T cell-deficient mice, and in mice that were congenitally deficient in CD4(+) T cells or depleted of these cells at the time of challenge. In contrast, mice congenitally deficient in, or depleted of, CD8(+) T cells were fully protected. Protection in this model was observed beyond 2 months after immunization, arguing against innate or nonspecific immune mechanisms. Thus, we find that immunity to pneumococcal colonization can be induced in the absence of antibody, independent of the capsular type, and this protection requires the presence of CD4(+) T cells at the time of challenge
Precise and accurate determination of the 8B decay spectrum
Accurate measurements of the 8B neutrino spectrum are important for the interpretation of solar neutrino data.
Experimentally, the 8B neutrino spectrum can be obtained from the measurement of the ÎČ-delayed α spectrum.
We report on an α-α coincidence measurement performed at the IGISOL facility in Jyvšaskylša, Finland. Our
measurement allows extensive cross-checks to be performed and gives a more intense neutrino spectrum at high
energies compared to the present standard. The deviation reaches 4% at the end point of the spectrum. Below
11 MeV, the deviation is less than 1%.status: publishe