Are the nearby groups of galaxies gravitationally bound objects?

We have compared numerical simulations to observations for the nearby (< 40 Mpc) groups of galaxies (Huchra & Geller 1982 and Ramella et al. 2002). The group identification is carried out using a group-finding algorithm developed by Huchra and Geller (1982). Using cosmological N-body simulation code with the LambdaCDM cosmology, we show that the dynamical properties of groups of galaxies identified from the simulation data are, in general, in a moderate, within 2sigma, agreement with the observational catalogues of groups of galaxies. As simulations offer more dynamical information than observations, we used the N-body simulation data to calculate whether the nearby groups of galaxies are gravitationally bound objects by using their virial ratio. We show that in a LambdaCDM cosmology about 20 per cent of nearby groups of galaxies, identified by the same algorithm as in the case of observations, are not bound, but merely groups in a visual sense. This is quite significant, specifically because estimations of group masses in observations are often based on an assumption that groups of galaxies found by the friends-of-friends algorithm are gravitationally bound objects. Simulations with different resolutions show the same results. We also show how the fraction of gravitationally unbound groups varies when the apparent magnitude limit of the sample and the value of the cosmological constant is changed. In general, a larger value of the Omega_Lambda generates slightly more unbound groups.Comment: 13 figures and 7 tables, Accepted 2007 September 19. Received 2007 September 19; in original form 2007 April

Russian orthography and learning to read

The unique structure of Russian orthography may influence the organization and acquisition of reading skills in Russian. The present review examines phonemic-graphemic correspondences in Russian orthography and discusses its grain-size units and possible difficulties for beginning readers and writers. Russian orthography is governed by a hierarchical, relatively regular 3-tier system of rules, complicated by numerous exceptions. Many theorists find that the key to this regularised complexity lies in Russian morphology. This review presents the perspectives of prominent Russian linguists on what linguistic units Russian orthography represents, and it evaluates and analyses their relevance for contemporary reading research

The parthenogenetic mite Labidostomma luteum (Acarina Actinotrichida: Labidostommidae) in Finland

Labidostommidae represents the only well sclerotized group of actinedid (prostigmatid) mites in Finland. This study confirms the presence of Labidostomma luteum Kramer, 1879 in southernmost Finland. This species has previously been reported in the nests of forest-dwelling singing birds without locality data, though the records were most probably based on misidentifications. Although it has not been found in arboreal nests, its known habitats in Finland indicate a wide ecological range within the SW archipelago. It has a patchy distribution and has been found in less than 8% of Berlese samples from suitable habitats in the SW archipelago. Only parthenogenetic populations of this species have been reported from Central Europe, with a limited area of bisexual populations in southern France. The 44 Finnish parthenogenetic populations have been mainly found in the SW archipelago on 29 islands. We report two mainland records from Sauvo in SW Finland with a widely separated record from Ylämaa, SE-Finland. This review of the total range of the species is based on a parallel revisional study of Labidostommidae. All stages of the parthenogenetic L. luteum are redescribed and SEM micrographs are presented for the most important diagnostic characters. L. luteum repetitor Grandjean, 1942 is raised to specific rank, and L. jacquemarti Coineau, 1964 is considered its junior synonym

Waste heat recovery : bottoming cycle alternatives

fi=vertaisarvioimaton|en=nonPeerReviewed

Simulation training streamlines the real-life performance in endovascular repair of ruptured abdominal aortic aneurysms

Objective: Difficulties in distributing endovascular experience among all operating room (OR) personnel prevented full-scale use of endovascular aneurysm repair (EVAR) in emergencies. To streamline the procedure of EVAR for ruptured aneurysm (rEVAR) and to provide this method even to unstable patients, we initiated regular simulation training sessions. Methods: This is an observational study of 29 simulation sessions performed between January 2015 and December 2017. We analyzed the development of time from OR door to aortic balloon occlusion during simulations and OR door to needle times in real-life rEVARs as well as the outcome of the 185 ruptured abdominal aortic aneurysm (rAAA) patients who arrived at the university hospital between January 2013 and December 2017. A questionnaire was sent for simulation attendants before and after the simulation session. Results: In the first simulations, the door to occlusion time was 20 to 35 minutes. After adding a hemodynamic collapse to the simulation protocol, the time decreased to 10 to 13 minutes in the 10 recent simulations, including a 5-minute cardiopulmonary resuscitation (P = .01). The electronic questionnaire performed for attendees before and after the simulation session showed significant improvement in both confidence and knowledge of the OR staff regarding rEVAR procedure. In the real-life rEVARs, 75 of the 185 patients with rAAAs underwent EVAR. Among rEVAR patients, the median OR door to needle time was 65 minutes before and 16 minutes after the onset of simulations (P = .000). The overall 30-day mortality among all rAAA patients was 44.8% and 30.6% accordingly (P = .046). When patients who were turned down from the emergency surgery were excluded, the 30-day operative mortality was 39.2% and 25.1% during the periods, respectively (P = .051). The 30-day mortality was 16.2% after rEVAR and 40.6% after open surgery (P = .001). Conclusions: Simulation training for rEVAR significantly improves the treatment process in real-life patients and may enhance the outcome of rAAA patients.Peer reviewe

Effects of long-range transported air pollution from vegetation fires on daily mortality and hospital admissions in the Helsinki metropolitan area, Finland

Introduction: Fine particulate matter (PM2.5) emissions from vegetation fires can be transported over long distances and may cause significant air pollution episodes far from the fires. However, epidemiological evidence on health effects of vegetation-fire originated air pollution is limited, particularly for mortality and cardiovascular outcomes. Objective: We examined association between short-term exposure to long-range transported PM2.5 from vegetation fires and daily mortality due to non-accidental, cardiovascular, and respiratory causes and daily hospital admissions due to cardiovascular and respiratory causes in the Helsinki metropolitan area, Finland. Methods: Days significantly affected by smoke from vegetation fires between 2001 and 2010 were identified using air quality measurements at an urban background and a regional background monitoring station, and modelled data on surface concentrations of vegetation-fire smoke. Associations between daily PM2.5 concentration and health outcomes on i) smoke-affected days and ii) all other days (i.e. non smoke days) were analysed using Poisson time series regression. All statistical models were adjusted for daily temperature and relative humidity, influenza, pollen, and public holidays. Results: On smoke-affected days, 10 mu g/m(3) increase in PM2.5 was associated with a borderline statistically significant increase in cardiovascular mortality among total population at a lag of three days (12.4%, 95% CI -0.2% to 26.5%), and among the elderly (>= 65 years) following same-day exposure (13.8%, 95% CI -0.6% to 30.4%) and at a lag of three days (11.8%, 95% CI -2.2% to 27.7%). Smoke day PM2.5 was not associated with non-accidental mortality or hospital admissions due to cardiovascular causes. However, there was an indication of a positive association with hospital admissions due to respiratory causes among the elderly, and admissions due to chronic obstructive pulmonary disease or asthma among the total population. In contrast, on non-smoke days PM2.5 was generally not associated with the health outcomes, apart from suggestive small positive effects on non-accidental mortality at a lag of one day among the elderly and hospital admissions due to all respiratory causes following same-day exposure among the total population. Conclusions: Our research provides suggestive evidence for an association of exposure to long-range transported PM2.5 from vegetation fires with increased cardiovascular mortality, and to a lesser extent with increased hospital admissions due to respiratory causes. Hence, vegetation-fire originated air pollution may have adverse effects on public health over a distance of hundreds to thousands of kilometres from the fires. (C) 2016 The Authors. Published by Elsevier Inc.Peer reviewe