31 research outputs found
Impacts of sea spray geoengineering on ocean biogeochemistry
We used an earth system model of intermediate complexity to study the effects of Solar Radiation Management (SRM) by sea spray geoengineering on ocean biogeochemistry. SRM slightly decreased global ocean net primary productivity (NPP) relative to the control run. The lower temperatures in the SRM run decreased NPP directly but also indirectly increased NPP in some regions due to changes in nutrient availability resulting from changes in ocean stratification and circulation. Reduced light availability had a minor effect on global total NPP but a major regional effect near the nutrient rich upwelling region off the coast of Peru, where light availability is the main limiting factor for phytoplankton growth in our model. Unused nutrients from regions with decreased NPP also fueled NPP elsewhere. In the context of RCP4.5 simulation used here, SRM decreased ocean carbon uptake due to changes in atmospheric CO2 concentrations, seawater chemistry, NPP, temperature, and ocean circulation
Standardised spider (Arachnida, Araneae) inventory of Kilpisjarvi, Finland
Background A spider taxonomy and ecology field course was organised in Kilpisjarvi Biological Station, northern Finland, in July 2019. During the course, four 50 x 50 m plots in mountain birch forest habitat were sampled following a standardised protocol. In addition to teaching and learning about spider identification, behaviour, ecology and sampling, the main aim of the course was to collect comparable data from the Kilpisjarvi area as part of a global project, with the purpose of uncovering global spider diversity patterns. New information A total of 2613 spiders were collected, of which 892 (34%) were adults. Due to uncertainty of juvenile identification, only adults are included in the data presented in this paper. The observed adult spiders belong to 51 species, 40 genera and 11 families, of which the Linyphiidae were the most rich and abundant with 28 (55%) species and 461 (52%) individuals. Lycosidae had six species and 286 individuals, Gnaphosidae five species and 19 individuals, Thomisidae four species and 24 individuals, Theridiidae two species and 23 individuals. All other six families had one species and less than 40 individuals. The most abundant species were the linyphiid Agnyphantes expunctus (204) and the lycosids Pardosa eiseni (164) and Pardosa hyperborea (107).Peer reviewe
Glial cell line-derived neurotrophic factor receptor REarranged during transfection agonist supports dopamine neurons in Vitro and enhances dopamine release In Vivo
Background Motor symptoms of Parkinson's disease (PD) are caused by degeneration and progressive loss of nigrostriatal dopamine neurons. Currently, no cure for this disease is available. Existing drugs alleviate PD symptoms but fail to halt neurodegeneration. Glial cell line-derived neurotrophic factor (GDNF) is able to protect and repair dopamine neurons in vitro and in animal models of PD, but the clinical use of GDNF is complicated by its pharmacokinetic properties. The present study aimed to evaluate the neuronal effects of a blood-brain-barrier penetrating small molecule GDNF receptor Rearranged in Transfection agonist, BT13, in the dopamine system. Methods We characterized the ability of BT13 to activate RET in immortalized cells, to support the survival of cultured dopamine neurons, to protect cultured dopamine neurons against neurotoxin-induced cell death, to activate intracellular signaling pathways both in vitro and in vivo, and to regulate dopamine release in the mouse striatum as well as BT13's distribution in the brain. Results BT13 potently activates RET and downstream signaling cascades such as Extracellular Signal Regulated Kinase and AKT in immortalized cells. It supports the survival of cultured dopamine neurons from wild-type but not from RET-knockout mice. BT13 protects cultured dopamine neurons from 6-Hydroxydopamine (6-OHDA) and 1-methyl-4-phenylpyridinium (MPP+)-induced cell death only if they express RET. In addition, BT13 is absorbed in the brain, activates intracellular signaling cascades in dopamine neurons both in vitro and in vivo, and also stimulates the release of dopamine in the mouse striatum. Conclusion The GDNF receptor RET agonist BT13 demonstrates the potential for further development of novel disease-modifying treatments against PD. (c) 2019 International Parkinson and Movement Disorder SocietyPeer reviewe
Copy number loss in SFMBT1 is common among Finnish and Norwegian patients with iNPH
Objective To evaluate the role of the copy number loss in SFMBT1 in a Caucasian population. Methods Five hundred sixty-seven Finnish and 377 Norwegian patients with idiopathic normal pressure hydrocephalus (iNPH) were genotyped and compared with 508 Finnish elderly, neurologically healthy controls. The copy number loss in intron 2 of SFMBT1 was determined using quantitative PCR. Results The copy number loss in intron 2 of SFMBT1 was detected in 10% of Finnish (odds ratio [OR] = 1.9, p = 0.0078) and in 21% of Norwegian (OR = 4.7, p <0.0001) patients with iNPH compared with 5.4% in Finnish controls. No copy number gains in SFMBT1 were detected in patients with iNPH or healthy controls. The carrier status did not provide any prognostic value for the effect of shunt surgery in either population. Moreover, no difference was detected in the prevalence of hypertension or T2DM between SFMBT1 copy number loss carriers and noncarriers. Conclusions This is the largest and the first multinational study reporting the increased prevalence of the copy number loss in intron 2 of SFMBT1 among patients with iNPH, providing further evidence of its role in iNPH. The pathogenic role still remains unclear, requiring further study.Peer reviewe
Ryhmä SO(3) ja sen lineaariset redusoitumattomat esitykset
Ryhmät ovat yksinkertaisina mutta elegantteina algebrallisina rakenteina jo pitkään olleet keskeinen
osa niin puhdasta kuin sovellettuakin matematiikkaa. Erityisesti ryhmät soveltuvat erilaisten
symmetrioiden esittämiseen. Ryhmien esitysteoriassa voidaan ryhmien rakennetta koskevia ongelmia
palauttaa lineaarialgebran ongelmiksi, jotka ovat hyvin ratkaistavissa. Tämä tapahtuu
kuvaamalla ryhmä homomorfisesti lineaarikuvausten ryhmään. Osoittautuu myös mielenkiintoiseksi
tutkia jo itsessään lineaarikuvauksista muodostuvien ryhmien epätriviaaleja lineaarisia
esityksiä.
Erityisen tarkastelun kohteena tutkielmassa on klassinen matriisiryhmä SO(3), joka siis koostuu
avaruuden ℝ3 rotaatiokuvauksista. Ryhmä SO(3) muiden klassisten matriisiryhmien tapaan
on erityisesti ns. Lien ryhmä, ts. sileä monisto siten, että ryhmän operaatio ja käänteisalkion
muodostaminen ovat vastaavassa mielessä sileitä kuvauksia (Sophus Lie, 1842-1899). Monistoja
puolestaan voidaan luonnehtia käyrien ja pintojen yleistyksiksi. Tarkemmin ilmaistuna monisto
on topologinen avaruus, joka on lokaalisti euklidinen, ts. jokaisella pisteellä on ympäristö, joka
on homeomorfinen jonkin euklidisen avaruuden ℝn avoimen joukon ts. kartan kanssa. Monisto
on sileä, jos siirtymät karttojen välillä ovat avaruuden ℝn sileitä kuvauksia.
Lien ryhmät ovat merkillisiä monistoja siinäkin mielessä, että niiden geometria on pitkälti kuvattavissa
algebrallisesti ns. Lien algebran avulla. Osoittautuu, että tämä Lien ryhmää vastaava
Lien algebra saadaan aina moniston tangenttiavaruudesta neutraalialkiolle. Riittävän siistissä
tapauksessa koko ryhmän geometria määräytyy pelkästään sitä vastaavasta Lien algebrasta.
Kuitenkin aina neutraalialkion sisältävä yhtenäinen komponentti määräytyy Lien ryhmää vastaavasta
Lien algebrasta.
Lien ryhmien esitysteoria eroaa hieman äärellisten ryhmien esitysteoriasta, sillä ryhmän rakenteen
säilymisen homomorfismissa lisäksi vaaditaan moniston sileän struktuurin säilymistä.
Lisäksi useat Lien ryhmät, kuten SO(3), ovat kompakteja. Tämä tarkoittaa puolestaan sitä,
että käyttöön saadaan myös kompaktien topologisten ryhmien esitysteorian tulokset, kuten unitaaristen
esitysten olemassaolo ja Peterin ja Weylin lause (Hermann Weyl, 1885-1955 sekä
hänen oppilaansa Fritz Peter, 1899-1949). Nämä perustuvat pohjimmiltaan ns. Haarin mitan
(Alfréd Haar, 1885-1933) olemassaoloon kaikilla lokaalisti kompakteilla topologisilla ryhmillä,
joita kompaktit ryhmät tietysti ovat.
Tutkielman päätuloksena esitetään ryhmän SO(3) redusoitumattomien esitysten konstruktio,
sekä todistus sille, että kaikki muut redusoitumattomat esitykset ovat ekvivalentteja tälle konstruktiolle.
Konstruktiossa päädytään ns. palloharmonisiin funktioihin.</p
Development of a Native Cross-Platform iRODS GUI Client
This paper describes activities on the research IT infrastructure development project at the University of Jyväskylä.
The main contribution is a cross-platform iRODS client application with a rich graphical user interface. The client
application is fully native and builds from a single C++ codebase on all of the platforms on which iRODS 4.0 is
supported. The application has a responsive UI with native look & feel and enables drag & drop integration to the
desktop. This is made possible by basing the development of the client application on top of the Qt 5 framework
and an object-oriented C++ framework for iRODS which is being developed with the client application. The objectoriented
framework wraps around the native iRODS 4.0 C/C++ client API library and provides object-oriented
interfaces to iRODS protocol operations e.g. a fully object-oriented iRODS General Query (GenQuery) interface
used by the client application has been implemented in this C++ framework. By developing on top of the native
C/C++ iRODS API library, the plugin architecture of iRODS 4.0 can be fully leveraged in authentication (e.g.
Kerberos) and network transport (e.g. SSL) modules without any additional complexity.nonPeerReviewe