Development of solute transport model and an application to describe field scale nitrogen processes

Suomessa pintavesiin kulkeutuvasta ihmisperäisestä typpikuormituksesta lähes 60 % on peräisin maataloudesta. Salaojitetuissa savimaissa erilaiset suuret huokoset eli makrohuokoset mahdollistavat nopean veden virtauksen sekä liuenneiden typpifraktioiden kulkeutumisen pellon pintaosista salaojiin. Savipeltojen hydrologiaa ja aineiden kulkeutumista kuvaavia malleja tarvitaan ravinnekuormitukseen vaikuttavien tekijöiden arvioimiseen. Tässä tutkimuksessa kehitettiin geneerinen, kolmiulotteinen, aineiden kulkeutumista kuvaava numeerinen malli. Kehitystyössä käytettiin hydrologista ja veden laadun aineistoa Etelä-Suomessa sijaitsevalta Nummelan koekentältä, joka kuuluu Salaojitustekniikat ja pellon vesitalouden optimointi -hankkeeseen. Kulkeutumismalli integroitiin osaksi kolmiulotteista hydrologista FLUSH-mallia, jolla voidaan kuvata veden virtausta ja eroosiota salaojitetuilla savimailla pohjoisilla leveysasteilla. Kehitetyllä aineiden kulkeutumismallilla voidaan simuloida useiden eri aineiden samanaikaisia prosesseja savimatriisissa ja makrohuokosissa. Simuloitavat aineet kulkeutuvat huokossysteemissä sekä niiden välillä advektio- ja dispersiomekanismien avulla. Pellon pinnalla aineen kulkeutumista kuvataan advektiolla. Maaperässä aineiden pidättymistä maapartikkeleihin voidaan kuvata lineaarisella, Freundlichin tai Langmuirin isotermeillä. Aineiden välille voidaan luoda reaktioketjuja, joissa hajoava aine muuttuu toiseksi aineeksi, ja hajoamisreaktioita voidaan säätää kosteus- ja lämpötilarajoittimilla. Pintakulkeutumista kuvaava osittaisdifferentiaaliyhtälö ratkaistaan iteroimalla. Maaperän kolmiulotteista kulkeutumista kuvaava osittaisdifferentiaaliyhtälöpari ratkaistaan vertikaalisessa suunnassa pentadiagonaalisella matriisialgoritmilla ja horisontaalisessa suunnassa iteroimalla. Kehitetty numeerinen ratkaisu rinnakkaistettiin MPI-rajapinnan avulla. Geneerinen aineiden kulkeutumismalli muokattiin kuvaamaan typen prosesseja. Kehitetyn typpimallin toimintaa arvioitiin soveltamalla sitä kasvukauden jälkeisinä syyskausina (2008 ja 2011) Nummelan koekentän savipeltolohkoille (1,3 ja 3,4 ha). Simulaatioilla tutkittiin ammoniumin- ja nitraattitypen kulkeutumista pinta- salaoja- ja pohjavesivaluntaan 1D maaprofiilissa. Sovelluksessa fraktioiden kulkeutumiseen vaikuttivat mineralisaatio-, nitrifikaatio- ja denitrifikaatioreaktiot sekä ammoniumtypen pidättyminen tasapainotilassa. Mallilla pystyttiin kuvaamaan nitraattitypen pitoisuuksien dynamiikkaa salaojavalunnassa, ja ammoniumtyppipitoisuuksissa saavutettiin mittausten mukainen kertaluokka. Kulkeutumismallin prosessien kuvausta arvioitiin myös herkkyysanalyysillä. Mallin lateraalisten komponenttien toiminnan varmistamiseksi typpimallia sovellettiin myös 3D simulaatioissa koko peltoalueelle (9,2 ha).In Finland, almost 60% of anthropogenic nitrogen (N) load originates from agriculture. In clayey fields, large pores, i.e. macropores, enable preferential flow and transport of dissolved nitrogen fractions from the tillage layer to subsurface drains. Models, which are able to describe hydrology and solute transport in clayey fields, are needed to evaluate factors that affect nutrient loading from cultivated fields. In this study, a new, generic, three-dimensional (3D) numerical model was developed to describe solute transport on the field surface and underlying soil layers. Hydrological and water quality data from the Nummela experimental field in southern Finland was applied in the development phase. The transport model was integrated into the 3D hydrological FLUSH model, which simulates water flow and soil erosion in clayey, subdrained cultivated fields in northern latitudes. The solute transport model can simultaneously describe movement and reactions of several solutes in the soil matrix and macropore systems. Transport of solutes is simulated with advection and dispersion mechanisms in the pore systems, and the same transport processes are applied to depict mass exchange between the pore systems. Solute transport on the field surface is described with advection. Adsorption of solutes in the subsurface system is based on the equilibrium adsorption approach using linear, Freudlich or Langmuir isotherm. It is possible to create reaction chains between solutes, where decaying solute is transformed into another solute in the simulation. The reaction processes can be adjusted with moisture and heat based limiters. The partial differential equation that describes overland transport is solved by iteration. Equations for the 3D transport in the subsurface profile are solved with the pentadiagonal matrix algorithm and horizontal fluxes by iteration. The numerical model was parallelized with the MPI application interface. An N transport model was developed from the generic solute transport model. The model was evaluated by simulating N processes during two autumn periods (2008 and 2011) in clayey field sections (1,3 and 3,4 ha) in the Nummela field. Simulations described transport of ammonium and nitrate in 1D soil profiles. N fractions were lost via tillage layer runoff, drainflow and horizontal groundwater outflow. In the application, transport of nitrogen fractions was affected by mineralisation, nitrification and denitrification reactions together with equilibrium sorption of ammonium. The model was able to simulate the dynamic increase of nitrate concentration in drainflow in the autumns, and the simulated ammonium concentrations in the drainflow were in the same order of magnitude as the concentrations derived from water sample analysis. Processes of the transport model were also evaluated with a sensitivity analysis, and the functioning of the lateral components was tested by conducting 3D simulations of nitrogen transport in the whole Nummela field area (9,2 ha)

Human myoma tissue-based extracellular matrix models for testing the effects of irradiation on the HPV positive cells

Background This study was designed to investigate the invasion of human papillomavirus (HPV) positive human cervical carcinoma cell lines in human leiomyoma-based extracellular matrices in vitro,and to test the suitability of the model for studying the irradiation effects on the cancer cell invasion. Methods HPV positive cervical carcinoma cell lines SiHa and CaSki, and HPV negative squamous cell carcinoma cell line HSC-3 were used. CaSki cells contain around 600 copies of HPV 16 virus in the genome, whereas SiHa have only 1-2 copies per cell. Cells were analyzed using two different human tumor derived extracellular matrix methods (3D myoma disc model, and Myogel Transwell invasion assay). Cultures were irradiated with 4 Gy. Myoma invasion area and the depth of invasion were measured with ImageJ 1.51j8 software. Statistical analyses were performed with SPSS Statistics (IBM SPSS (R) Statistics 25). Results All cells invaded through Myogel coated Transwell membranes and within myoma discs. In myoma discs, a difference in the invasion depth (p = 0.0001) but not in invasion area (p = 0.310) between the HPV positive cell lines was seen, since SiHa (less HPV) invaded slightly better than CaSki (more HPV). HSC-3 cells (HPV negative) invaded deepest (p = 0.048) than either of the HPV positive cell line cells. No difference was detected in the invasion area (p = 0.892) between HPV positive and HPV negative cells. The ionized radiation significantly reduced the invasion depth of HSC-3 (p = 0.008), SiHa (p = 0.0001) and CaSki (p = 0.005). No significant effect on the invasion area was detected in any of the cell lines. However, a significant difference was observed between SiHa and CaSki in the reduction of the invasion depth after radiation (p = 0.013) as the reduction was greater with SiHa than CaSki. Conclusions Both solid and gelatinous human leiomyoma-based extracellular matrix models were suitable platforms to study the invasion of HPV positive cervical carcinoma cells in vitro. SiHa cells with less HPV copy number cells invaded slightly better and were slightly more sensitive to irradiation than CaSki cells with high HPV copy number. However, there was no drastic differences between the invasion properties of these carcinoma cells.Peer reviewe

Impacts of supplementary drainage on the water balance of a poorly drained agricultural field

In northern clay soils, field drainage is needed to ensure suitable moisture conditions for crop growth and farming operations. Supplementary drainage installations improve the efficiency of old drainage systems, but the hydrological impacts of the drainage procedures are not comprehensively understood or quantified. The objective was to simulate the hydrological behavior of a clay field section and to quantify the effects of a supplementary drainage on the water balance of the field section. The study site, in southern Finland, was originally subsurface drained in 1952 with 32 m drain spacing. Supplementary drainage was installed in 2014, decreasing the drain spacing to 10.7 m. Simulations were carried out with a dual-permeability hydrological model and two model parametrizations describing the field hydrology (1) before and (2) after the supplementary drainage installation. The parameterizations were used for simulations of a nine-year period to quantify the hydrological impacts of the supplementary drainage. For the periods without snow on the ground, the modified Nash-Sutcliffe efficiency for daily drain discharge and topsoil layer runoff values ranged from 0.43 to 0.53 and from 0.44 to 0.53, respectively. During the original drainage setup scenario, the average annual drain discharge was lower (7.8% of precipitation) than topsoil layer runoff and groundwater outflow (10.3% and 26.4%, respectively). For the supplementary drainage scenario, most of the water outflow was through drain discharge and groundwater outflow (20.4% and 21.9%, respectively). The supplementary drainage installation increased the average annual drain discharge by a factor of 2.6, while the annual average topsoil layer runoff and groundwater outflow decreased by 75% and 18%, respectively. The supplementary drainage setup was found to expedite the drying of the field section in spring by 8 days on average compared to the original drainage setup.Peer reviewe

Bioreactivity, Guttation and Agents Influencing Surface Tension of Water Emitted by Actively Growing Indoor Mould Isolates

The secretion of metabolites in guttation droplets by indoor moulds is not well documented. This study demonstrates the guttation of metabolites by actively growing common indoor moulds. Old and fresh biomasses of indoor isolates of Aspergillus versicolor, Chaetomium globosum, Penicillium expansum, Trichoderma atroviride, T. trixiae, Rhizopus sp. and Stachybotrys sp. were compared. Metabolic activity indicated by viability staining and guttation of liquid droplets detected in young (6 months old) cultures consisting of dehydrated hyphae and dormant conidia. Fresh

Vesitalouden hallinta vesiensuojelussa (VesiHave)

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Bisfenolijohdannaiset : altistuminen ja terveysriskit rakennusalalla

Työterveyslaitoksen toteuttamassa ja Työsuojelurahaston rahoittamassa tutkimushankkeessa selvitettiin rakennusalan työntekijöiden altistumista epoksihartseissa käytetyille bisfenoliyhdisteille. Tutkimukseen osallistui 15 miespuolista työntekijää kahdesta eri työpaikasta, jotka tekivät viemäriputkien sukitusta ja lattiapinnoitusta. Työntekijöiltä kerättiin virtsanäytteitä viitenä eri ajankohtana (nollanäyte vapaan jälkeen, aamunäyte ennen työvuoroa, työvuoron jälkeen, työpäivän iltanäyte ja aamunäyte ennen seuraavaa työvuoroa), jotta kemikaalien poistumista elimistöstä pystyttiin paremmin arvioimaan. Virtsanäytteistä mitattiin seuraavia kemikaaleja: bisfenoli A (BPA), bisfenoli F (BPF), bisfenoli A diglysidyylieetteri (BADGE) ja bisfenoli F diglysidyylieetteri (BFDGE) sekä kahden jälkimmäisen aineenvaihduntatuotteita [bisfenoli A (2,3-dihydroksipropyyli) glysidyylieetteri (BADGE·H2O), bisfenoli A bis(2,3-dihydroksipropyyli) eetteri (BADGE·2H2O), bisfenoli A (3-kloori-2-hydroksipropyyli) (2,3-dihydroksipropyyli) eetteri (BADGE·HCl·H2O), bisfenoli A (3-kloori-2-hydroksipropyyli) glysidyylieetteri (BADGE·HCl), ja bisfenoli A bis(3-kloori- 2-hydroksipropyyli) eetteri (BADGE·2HCl) sekä bisfenoli F bis(2,3-dihydroksipropyyli) eetteri (BFDGE·2H2O), ja bisfenoli F bis(3-kloori-2-hydroksipropyyli) eetteri (BFDGE·2HCl)]. Työntekijöiden mittaustuloksia verrattiin työssään altistumattoman vertailuryhmän mittaustuloksiin. Vertailuhenkilöiltä kerättiin yksi virtsanäyte, joka otettiin aamulla. Työntekijöiltä kerättiin myös hengitysvyöhykeilmanäytteitä sekä käsienpyyhintänäytteitä. Kaikki mittausmenetelmät kehitettiin tässä hankkeessa. Työpaikoilla käytetyissä epoksipohjaisissa aineissa ei ollut mukana BPA:ta eikä BPF:ä, vaan ne koostuivat BADGE- ja BFDGE-pohjaisista epoksihartseista. Näin ollen työntekijöiden virtsanäytteiden BPA- ja BPF-pitoisuudet olivat samaa luokkaa kuin vertailuväestön vastaavat pitoisuudet. Sen sijaan osasta työntekijöiden virtsanäytteistä löytyi korkeampia BADGE- ja BFDGE-aineenvaihduntatuotteiden pitoisuuksia kuin vertailuryhmän näytteistä. Tämä viittaa työperäiseen altistumiseen BADGE:lle ja BFDGE:lle. Myös seuraavana päivänä kerätyistä näytteistä mitattiin selkeästi koholla olevia kemikaalipitoisuuksia, mikä viittaa ihon kautta tapahtuneeseen altistumiseen. Molemmilla työpaikoilla käytettiin koostumukseltaan suurin piirtein samanlaisia epoksivalmisteita. Tämä näkyy myös mittaustuloksissa, sillä molempien työpaikkojen työntekijöiden mittaustulokset olivat hyvin saman suuntaisia. Koska kyse on ihoa pienillä pitoisuuksilla herkistävistä aineista, näiden aineiden pääsy iholle ja imeytyminen elimistöön ihon läpi tulisi estää. Nyt saadut tulokset korostavat ennestään ihon kunnollisen suojaamisen tärkeyttä epoksitöissä. Turvallisesta epoksituotteiden käytöstä pinnoitustyössä on Työterveyslaitos tuottanut aiemmin ns. Epoksikansion, josta löytyy ohjeistusta mm. käsineiden valintaan epoksityössä (www.ttl.fi/epoksikansio). Tässä tutkimuksessa mitatut virtsapitoisuudet olivat sen verran matalia, että muut terveyshaitat aineiden imeytymisestä johtuen eivät ole nykytiedon valossa todennäköisiä. Altistumisen seurantaan tulee jatkossakin kiinnittää huomiota jo pelkästään senkin takia, että tämän tutkimuksen otos oli varsin kapea. Biomonitorointi tarjoaa altistumisen arviointiin hyvän työkalun. Työntekijöiden hengitysvyöhykkeeltä kerätyistä ilmanäytteistä pystyttiin mittaamaan BADGE:a ja BFDGE:tä, mutta pitoisuudet olivat matalia. Käsienpyyhintänäytteistä löytyi myös BADGE:a ja BFDGE:tä, varsinkin lattiapinnoitustyöpaikan näytteistä, mikä viittaisi myös siihen, että altistuminen on tapahtunut ainakin osittain ihon kautta. Tässä tutkimushankkeessa saatuja tuloksia voidaan jatkossa hyödyntää työperäisen bisfenolialtistumisen lisäksi myös kemikaaliturvallisuuteen liittyvässä viranomaistyössä esim. uusia altistumisen raja-arvoja asetettaessa sekä harkittaessa mahdollisia rajoituksia näiden aineiden käytölle

Chaetomium and Chaetomium-like Species from European Indoor Environments Include Dichotomopilus finlandicus sp. nov.

The genus Chaetomium is a frequently occurring fungal taxon world-wide. Chaetomium and Chaetomium-like species occur in indoor environments, where they can degrade cellulose-based building materials, thereby causing structural damage. Furthermore, several species of this genus may also cause adverse effects on human health. The aims of this research were to identify Chaetomium and Chaetomium-like strains isolated from indoor environments in Hungary and Finland, two geographically distant regions of Europe with drier and wetter continental climates, respectively, and to study their morphological and physiological properties, as well as their extracellular enzyme activities, thereby comparing the Chaetomium and Chaetomium-like species isolated from these two different regions of Europe and their properties. Chaetomium and Chaetomium-like strains were isolated from flats and offices in Hungary, as well as from schools, flats, and offices in Finland. Fragments of the translation elongation factor 1α (tef1α), the second largest subunit of RNA polymerase II (rpb2) and β-tubulin (tub2) genes, as well as the internal transcribed spacer (ITS) region of the ribosomal RNA gene cluster were sequenced, and phylogenetic analysis of the sequences performed. Morphological examinations were performed by stereomicroscopy and scanning electron microscopy. Thirty-one Chaetomium sp. strains (15 from Hungary and 16 from Finland) were examined during the study. The most abundant species was Ch. globosum in both countries. In Hungary, 13 strains were identified as Ch. globosum, 1 as Ch. cochliodes, and 1 as Ch. interruptum. In Finland, 10 strains were Ch. globosum, 2 strains were Ch. cochliodes, 2 were Ch. rectangulare, and 2 isolates (SZMC 26527, SZMC 26529) proved to be representatives of a yet undescribed phylogenetic species from the closely related genus Dichotomopilus, which we formally describe here as the new species Dichotomopilus finlandicus. Growth of the isolates was examined at different temperatures (4, 15, 20, 25, 30, 37, 35, 40, and 45 °C), while their extracellular enzyme production was determined spectrophotometrically

Chaetomium and Chaetomium-like Species from European Indoor Environments Include Dichotomopilus finlandicus sp. nov.

The genus Chaetomium is a frequently occurring fungal taxon world-wide. Chaetomium and Chaetomium-like species occur in indoor environments, where they can degrade cellulose-based building materials, thereby causing structural damage. Furthermore, several species of this genus may also cause adverse effects on human health. The aims of this research were to identify Chaetomium and Chaetomium-like strains isolated from indoor environments in Hungary and Finland, two geographically distant regions of Europe with drier and wetter continental climates, respectively, and to study their morphological and physiological properties, as well as their extracellular enzyme activities, thereby comparing the Chaetomium and Chaetomium-like species isolated from these two different regions of Europe and their properties. Chaetomium and Chaetomium-like strains were isolated from flats and offices in Hungary, as well as from schools, flats, and offices in Finland. Fragments of the translation elongation factor 1α (tef1α), the second largest subunit of RNA polymerase II (rpb2) and β-tubulin (tub2) genes, as well as the internal transcribed spacer (ITS) region of the ribosomal RNA gene cluster were sequenced, and phylogenetic analysis of the sequences performed. Morphological examinations were performed by stereomicroscopy and scanning electron microscopy. Thirty-one Chaetomium sp. strains (15 from Hungary and 16 from Finland) were examined during the study. The most abundant species was Ch. globosum in both countries. In Hungary, 13 strains were identified as Ch. globosum, 1 as Ch. cochliodes, and 1 as Ch. interruptum. In Finland, 10 strains were Ch. globosum, 2 strains were Ch. cochliodes, 2 were Ch. rectangulare, and 2 isolates (SZMC 26527, SZMC 26529) proved to be representatives of a yet undescribed phylogenetic species from the closely related genus Dichotomopilus, which we formally describe here as the new species Dichotomopilus finlandicus. Growth of the isolates was examined at different temperatures (4, 15, 20, 25, 30, 37, 35, 40, and 45 °C), while their extracellular enzyme production was determined spectrophotometrically