6 resultados para NI-CU ALLOYS
em Helda - Digital Repository of University of Helsinki
Resumo:
The goal of this thesis was to examine the ecophysiological responses of Scots pine (Pinus sylvestris L.), with an emphasis on the oxidative enzyme peroxidase and plant phenolics to environmental stresses like elevated levels of nickel (Ni) and copper (Cu), and herbivory. The effects of Ni and Cu were studied in a gradient survey at a sulphur dioxide contaminated site in the Kola Peninsula, and with experiments in which seedlings were exposed to Ni mist or to Ni and Cu amended into the soil. In addition, experimental Ni exposure was combined with disturbance of the natural lichen cover of the forest ground layer. Pine sawfly attack was simulated in the early season defoliation experiment, in which mature Scots pine were defoliated (100 %) during two successive years in a dry, nutrient-poor Scots pine stand. In addition, the effect of previous defoliation on the growth of sawfly (Diprion pini L.) larvae was studied. Apoplastic peroxidase activity was elevated in the needles of pine in a Ni- , Cu- and SO2- polluted environment, which indicated an increased oxidative stress. Increased foliar peroxidase activity due to Ni contamination was shown in the experiment, in which Ni was added as mist. No such response was found in peroxidase acitivity of the roots exposed to elevated Ni and/or Cu in the soil. Elevated Ni in the soil increased the concentration of foliar condensed tannins, which are able to bind heavy metals in the cells. Addition of low levels of Ni in the soil appeared to benefit pine seedlings, which was seen as promoted shoot growth and better condition of the roots. Wet Ni deposition of 2000 mg m-2 reduced growth and survival of pine seedlings, whereas deposition levels 200 mg m-2 or 20 mg m-2 caused no effects in a 2-y lasting experiment. The lichen mat on the forest floor did not act as an effective buffer against the adverse impacts of heavy metals on pine seedlings. However, some evidence was found indicating that soil microbes profited from the lichen mat. Artificial defoliation increased peroxidase activity in the Scots pine needles. In addition, defoliation decreased nitrogen, diamine putrescine and glucose concentrations in the needles and increased the concentrations of several phenolic compounds, starch and sucrose. Previous artificial defoliation led to poor growth of sawfly larvae reared on the pines, suggesting delayed induced resistance in Scots pine. However, there was no consistent relationship between inducibility (proportional increase in a compound following defoliation) and adverse effects on the growth of pine sawfly larvae. The observed inducible responses in needle phenolics due to previous defoliation thus appear to represent non-specific responses against sawflies.
Resumo:
The thesis addresses the problem of Finnish Iron Age bells, pellet bells and bell pendants, previously unexplored musical artefacts from 400–1300 AD. The study, which contributes to the field of music archaeology, aims to provide a gateway to ancient soundworlds and ideas of music making. The research questions include: Where did these metal artefacts come from? How did they sound? How were they used? What did their sound mean to the people of the Iron Age? The data collected at the National Museum of Finland and at several provincial museums covers a total of 486 bells, pellet bells and bell pendants. By means of a cluster analysis, each category was divided into several subgroups. The subgroups, which all seem to have a different dating and geographical distribution, represent a spread of both local and international manufacturing traditions. According to an elemental analysis, the material varies from iron to copper-tin, copper-lead and copper-tin-lead alloys. Clappers, pellets and pebbles prove that the bells and pellet bells were indisputably instruments intended for sound production. Clusters of small bell pendants, however, probably produced sound by jingling against each other. Spectrogram plots reveal that the partials of the still audible sounds range from 1 000 to 19 850 Hz. On the basis of 129 inhumation graves, hoards, barrows and stray finds, it seems evident that the bells, pellet bells and bell pendants were fastened to dresses and horse harnesses or carried in pouches and boxes. The resulting acoustic spaces could have been employed in constructing social hierarchies, since the instruments usually appear in richly furnished graves. Furthermore, the instruments repeatedly occur with crosses, edge tools and zoomorphic pendants that in the later Finnish-Karelian culture were regarded as prophylactic amulets. In the Iron Age as well as in later folk culture, the bell sounds seem to have expressed territorial, social and cosmological boundaries.
Resumo:
The low solubility of iron (Fe) depresses plant growth in calcareous soils. In order to improve Fe availability, calcareous soils are treated with synthetic ligands, such as ethylenediaminetetraacetic acid (EDTA) and ethylenediimi-nobis(2-hydroxyphenyl)acetic acid (EDDHA). However, high expenses may hinder their use (EDDHA), and the recalcitrance of EDTA against biodegra-dation may increase the potential of cadmium (Cd) and lead (Pb) leaching. This study evaluated the ability of biodegradable ligands, i.e. different stereo-isomers of ethylenediaminedisuccinic acid (EDDS), to provide Fe for lettuce (Lactuca sativa L.) and ryegrass (Lolium perenne cv. Prego), their effects on uptake of other elements and solubility in soils and their subsequent effects on the activity of oxygen-scavenging enzymes in lettuce. Both EDTA and EDDHA were used as reference ligands. In unlimed and limed quartz sand both FeEDDS(S,S) and a mixture of stereo-isomers of FeEDDS (25% [S,S]-EDDS, 25% [R,R]-EDDS and 50% [S,R]/[R,S]-EDDS), FeEDDS(mix), were as efficient as FeEDTA and FeEDDHA in providing lettuce with Fe. However, in calcareous soils only FeEDDS(mix) was comparable to FeEDDHA when Fe was applied twice a week to mimic drip irrigation. The Fe deficiency increased the manganese (Mn) concentration in lettuce in both acidic and alkaline growth media, whereas Fe chelates depressed it. The same was observed with zinc (Zn) and copper (Cu) in acidic growth media. EDDHA probably affected the hormonal status of lettuce as well and thus depressed the uptake of Zn and Mn even more. The nutrient concentrations of ryegrass were only slightly affected by the Fe availability. After Fe chelate splitting in calcareous soils, EDDS and EDTA increased the solubility of Zn and Cu most, but only the Zn concentration was increased in lettuce. The availability of Fe increased the activity of oxygen-scavenging enzymes (ascorbate peroxidase, guaiacol peroxidase, catalase). The activity of Cu/ZnSOD (Cu/Zn superoxide dismutase) and MnSOD in lettuce leaves followed the concentrations of Zn and Mn. In acidic quartz sand low avail-ability of Fe increased the cobalt (Co) and nickel (Ni) concentrations in let-tuce, but Fe chelates decreased them. EDTA increased the solubility of Cd and Pb in calcareous soils, but not their uptake. The biodegradation of EDDS was not affected by the complexed element, and [S,S]-EDDS was biodegraded within 28 days in calcareous soils. EDDS(mix) was more recalcitrant, and after 56 days of incubation water-soluble elements (Fe, Mn, Zn, Cu, Co, Ni, Cd and Pb) corresponded to 10% of the added EDDS(mix) concentration.
Resumo:
Työ on uskontososiologian tutkimusalaan lukeutuva laadullinen tapaustutkimus, joka perustuu argumentatiiviseen haastatteluaineistoon ja sosiaalisen identiteetin teoriaan. Tutkimuskysymys liittyy sosiaalisen identiteettiin. Miten suomenuskoinen hahmottaa oman yhteisönsä ja sen jäsenyyden? Mitä merkitystä yhteisöllä on suomenuskoiselle? Tutkimuksen aihepiiri on suomalainen uuspakanuus ja sen eräs suuntaus, suomenusko. Työn eräänä tarkoituksena on määritellä suomenuskon käsitettä ja sijoittaa suomenuskoinen suuntaus nykyajan suomalaisen uuspakanuuden kentälle. Hypoteesin mukaan suomenusko on uusiin uskontoihin lukeutuva uuspakanallinen liike. Se kuuluu ásatrún tavoin etnopakanuuden luokkaan, eli kansallisista muinaisperinteistä inspiraationsa ammentaviin suuntauksiin. Suomenuskolle on omalaatuista esikristillisten suomalaisten uskontoperinteiden sekä suomalaisen kansanuskon korostaminen lähteinä. Suomenuskon muut ominaispiirteet vastaavat tyypillistä uuspakanuutta: Luonnon ja perinteiden kunnioitus sekä epädogmaattisuus ja tasavertaisuus ovat keskeisiä arvoja. Työ tehtiin puolistrukturoituna haastattelututkimuksena. Seitsemää suomenuskoista haastateltiin laadullisen asennetutkimuksen menetelmän mukaisesti. Menetelmä on uudehko ja kiinnostava. Se perustuu argumentatiivisen haastatteluaineiston tuottamiseen väittämäkorttien avulla. Analyysissä haastatteluaineistosta paikannetaan asenteita, eli subjektin ilmaisemaa jonkin kohteen arvottamista. Asenteista pyrittiin löytämään ulkoryhmiin kohdistuvia vertailuja ja retorisia erottautumisia. Työn teoreettisena tukirankana on Henri Tajfelin ja John C. Turnerin kehittämä sosiaalisen identiteetin teoria. Teorian mukaan sosiaalista identiteettiä on mahdollista tutkia ainoastaan sosiaalisten ryhmien keskinäisen vertailun asetelmassa. Omia sisäryhmiä vertaillaan aina ulkoryhmiin siten, että oma ryhmä näyttäytyy voittajana. Tämä takaa yksilölle myönteisen omanarvontunnon. Karmela Liebkindin mukaan vähemmistöryhmät vertailevat itseään valtakulttuurin enemmistöryhmiin. Heikki Pesosen ja Elina Huhdan mukaan vähemmistöuskonnot pyrkivät oikeuttamaan omaa uskontoaan tekemällä omalle ryhmälle suotuisia vertailuja. Tutkimuksessa havaittiin haastateltavien tekemiä retorisia erottautumisia ulkoryhmistä sekä heidän ilmaisemiaan asenteita, jotka liittyvät suomenuskoisten sisäryhmän dynamiikkaan. Tulosten perusteella haastatellut suomenuskoiset erottautuvat ryhmänä muusta uuspakanuudesta ja vielä selvemmin New Agesta ja satanismista, jotka eivät ole uuspakanuutta. Lisäksi haastateltavat korostavat eroa dogmaattisiin valtauskontoihin, varsinkin evankelis-luterilaisen valtionkirkon enemmistöryhmään. Suomenuskoisten yhteisöön liittymisen prosessin havaittiin muistuttavan sosiaalista itsekategorisointia yhteisön jäsenyydessä ratkaiseva tekijä on oman jäsenyyden tajuaminen itse. Teorian mukaan tämä johtaa sosiaalisen identiteetin muodostumiseen ja siten ryhmäkäyttäytymiseen. Haastateltavilla oli havaittavissa vahva sosiaalinen identiteetti. Uuspakanuuden kenttään suhteutettuna se oli poikkeuksellisen yhtenäinen. Lisäksi selvisi, että suomenuskoiset suunnittelevat uskonnolliseksi yhdyskunnaksi rekisteröitymistä.