Early experience with robotic mitral valve repair with intra-aortic occlusion

Objective: To report the learning curve and early results of robotic mitral valve repairs in comparison with propensity score-matched sternotomy controls after the adoption of a robotic mitral valve surgery program in a university teaching hospital. Methods: A total of 142 patients underwent robotic mitral valve repair due to degenerative mitral regurgitation between May 2011 and December 2015. Control patients operated on via the conventional sternotomy approach were selected by the use of propensity score analysis resulting in 2 well-matched study groups. Results: Valve repair rate was 98.6% and 97.9% in the robotic and sternotomy groups, respectively. Operation length, cardiopulmonary bypass, aortic crossclamp, and ventilation times were shorter in the sternotomy group. All of these times were statistically significantly reduced within the robotic group during the learning curve. Even though there was no statistically significant difference in the rate of perioperative complications between the groups, 3 patients in the robotic group required postoperative extracorporeal membrane oxygenation due to low cardiac output, and 1 patient in the robotic group died. In the robotic and sternotomy groups, 86.3% versus 84.7% of patients had grade Conclusions: The present series reports the entire early learning curve related to the introduction of robotic mitral valve repair in our institution. In all, repair rate and early durability were acceptable, but more patients in the robotic group had serious complications. Early major robotic complications that occurred may have been related to the simultaneous use of intra-aortic occlusion.Peer reviewe

Kalvobioreaktori biojätteiden kompostoinnin jätevesille

Kalvobioreaktori on biologisen jätevedenpudistuksen kehittynyt muoto, jossa lietteen erotus puhdistetusta jätevedestä tapahtuu kalvosuodatuksella tavanomaisen selkeytyksen sijasta. Erilaisten biomassojen prosessointi lisääntyy ja jätevedet näistä toiminnoista ovat usein erittäin väkeviä. Tässä tutkimushankkeessa kalvobioreaktorin toimintaa tutkittiin biojätteiden kompostoinnista tulevien jätevesien puhdistukseen. Biologisen typenpoiston eri vaiheiden toimintaedellytykset turvattiin alkalilla (nitrifikaatio) ja hiililähteellä (denitrifikaatio). Prosessialtaaseen upotetuista ultrasuodatuskalvoista (PVDF onttokuidut) aktiivilieteprosessin erotusmenetelmänä saatiin merkittävä positiivinen kokemus toimittaessa kapasiteetin matalalla käyttöasteella. Puhdistustulos biojätteiden kompostoinnin erittäin väkeville jätevesille oli hyvä ja noin 2,5 vuoden tutkimusjakson jälkeen kalvojen alkuperäisestä vuoarvosta oli likaantumisen takia menetetty alle 10 %. Soveltamalla tutkimuksen aikana hyväksi osoittautuneita kalvojen pesumenetelmiä, tätä tulosta voidaan todennäköisesti parantaa. Sekä bioprosessin että kalvoprosessin suhteen tutkimusta ja prosessien optimointia tulee jatkaa korkeampiin kuormitusasteisiin siten, että kalvoerotuksen soveltamisen edut näissä ”ääritilanteissa” tulevat voimakkaammin esille esim. bioprosessin alenevan puhdistustehon osittaisena korvaajana. Lähes kiintoainevapaa vesi kalvobioreaktorista luo edellytykset mm. kustannustehokkaille jatkokäsittelyille kuten UV-desinfioinnille veden vaativaa uudelleen käyttöä varten

Population fluctuations and spatial synchrony in an arboreal rodent

Climatic conditions, trophic links between species and dispersal may induce spatial synchrony in population fluctuations. Spatial synchrony increases the extinction risk of populations and, thus, it is important to understand how synchrony-inducing mechanisms affect populations already threatened by habitat loss and climate change. For many species, it is unclear how population fluctuations vary over time and space, and what factors potentially drive this variation. In this study, we focus on factors determining population fluctuations and spatial synchrony in the Siberian flying squirrel, Pteromys volans, using long-term monitoring data from 16 Finnish populations located 2-400 km apart. We found an indication of synchronous population dynamics on a large scale in flying squirrels. However, the synchrony was not found to be clearly related to distance between study sites because the populations seemed to be strongly affected by small-scale local factors. The regularity of population fluctuations varied over time. The fluctuations were linked to changes in winter precipitation, which has previously been linked to the reproductive success of flying squirrels. Food abundance (tree mast) and predator abundance were not related to population fluctuations in this study. We conclude that spatial synchrony was not unequivocally related to distance in flying squirrels, as has been observed in earlier studies for more abundant rodent species. Our study also emphasises the role of climate in population fluctuations and the synchrony of the species

Population fluctuations and spatial synchrony in an arboreal rodent

Climatic conditions, trophic links between species and dispersal may induce spatial synchrony in population fluctuations. Spatial synchrony increases the extinction risk of populations and, thus, it is important to understand how synchrony-inducing mechanisms affect populations already threatened by habitat loss and climate change. For many species, it is unclear how population fluctuations vary over time and space, and what factors potentially drive this variation. In this study, we focus on factors determining population fluctuations and spatial synchrony in the Siberian flying squirrel, Pteromys volans, using long-term monitoring data from 16 Finnish populations located 2-400 km apart. We found an indication of synchronous population dynamics on a large scale in flying squirrels. However, the synchrony was not found to be clearly related to distance between study sites because the populations seemed to be strongly affected by small-scale local factors. The regularity of population fluctuations varied over time. The fluctuations were linked to changes in winter precipitation, which has previously been linked to the reproductive success of flying squirrels. Food abundance (tree mast) and predator abundance were not related to population fluctuations in this study. We conclude that spatial synchrony was not unequivocally related to distance in flying squirrels, as has been observed in earlier studies for more abundant rodent species. Our study also emphasises the role of climate in population fluctuations and the synchrony of the species.Peer reviewe