Pollen mother cells of Tradescantia clone 4430 and Tradescantia pallida var. purpurea are equally sensitive to the clastogenic effects of X-rays

The Tradescantia micronucleus test is a sensitive bioassay for mutagenesis that may be employed both under field and laboratory conditions. This test has been standardized mostly on the basis of the results obtained with clone 4430. However, this clone is not well adapted to tropical weather, frequently showing problems with growth and flowering. In addition, it is attacked by parasites and insects, a fact that limits its use in field studies aiming at the biomonitoring of air pollution. In the city of São Paulo, Tradescantia pallida (Rose) Hunt. var. purpurea Boom is widely distributed as an ornamental plant in gardens and along roadsides and streets, mostly because of its natural resistance and its easy propagation. In this report, we present dose-response curves indicating that the sensitivity of T. pallida and clone 4430 to X-radiation (1, 10, 25 and 50 cGy) is similar. The results confirm our previous suggestion that T. pallida represents a good alternative for in situ mutagenesis testing in tropical regions, especially biomonitoring studies in which the exposure conditions may not be fully controllable.

Usean näytön hyödyntäminen Windows-ympäristössä

Tässä kandidaatintyössä luodaan kattava katsaus erilaisiin PC-laiteissa toimiviin usean näytön käyttöönottomenetelmiin, joita on olemassa useita ominaisuuksiltaan ja käyttötarkoituksiltaan erilaisia. Työssä perehdytään Windowsin usean näytön tuen historiaan ja sen kehitykseen eri Windows versioiden välillä tuen alkuajoista 1990-luvulta nykyaikaan aina viimeisimpiin Windows käyttöjärjestelmiin asti. Lopuksi tarkastellaan vielä pelien usean näytön tukea ja kuinka hyödyntää useaa näyttöä sellaisissa peleissä, jotka eivät sitä sisäänrakennetusti tue.

Radioaktiivisen päästön ennustaminen valmiustilanteessa

Ydinvoimaloissa käytetään toiminnallisia syvyyssuuntaisia puolustustasoja ydinturvallisuuden varmistamiseksi. Puolustuksen viidennessä ja viimeisessä tasossa pyritään lieventämään vakavan onnettomuuden ympäristövaikutuksia ja väestöön kohdistuvaa säteilyaltistusta. Suojelutoimien onnistumisen kannalta on tärkeää pystyä arvioimaan etukäteen radioaktiivisen päästön suuruus ja ajankohta mahdollisimman tarkasti. Tässä diplomityössä on esitelty radioaktiivisen päästön suuruuteen ja ajankohtaan vaikuttavat ilmiöt sekä niihin liittyvät merkittävät epävarmuudet. Ydinvoimalaitosten turvallisuusjärjestelmien osalta tarkastelun kohteena ovat suomalaiset käynnissä olevat reaktorit Olkiluoto 1 & 2 sekä Loviisa 1 & 2. Kaikissa Suomen laitoksissa on käytössä vakavan onnettomuuden hallintaan soveltuvia järjestelmiä ja toimintoja. Työssä etsittiin tietoa eri maiden radioaktiivisen päästön ennustamiseen käytettävistä ohjelmista. Eri mailla on eri toimintaperiaatteilla ja laajuuksilla toimivia ohjelmia. Osassa työkaluja käytetään ennalta laskettuja tuloksia ja osassa onnettomuustilanteet lasketaan onnettomuuden aikana. Lisäksi lähivuosina Euroopassa on tavoitteena kehittää yhteistyömaille yhteisiä valmiuskäyttöön soveltuvia ohjelmia. Työssä kehitettiin uusi valmiustyökalu Säteilyturvakeskuksen käyttöön Microsoft Excelin VBAohjelmoinnin avulla. Valmiustyökalu hyödyntää etukäteen laskettujen todennäköisyyspohjaisten analyysien onnettomuussekvenssejä. Tällöin valmiustilanteessa laitoksen tilanteen kehittymistä on mahdollista arvioida suojarakennuksen toimintakyvyn perusteella. Valmiustyökalu pyrittiin kehittämään mahdollisimman helppokäyttöiseksi ja helposti päivitettäväksi.

Mikro-ORC-energianmuuntimen suorituskyvyn todentaminen ja kaupallistaminen

Tässä työssä esitellään yleisesti ORC-prosessi, sen toimintaperiaate ja käyttökohteet. Työn tavoitteena oli todentaa diesel-moottorin savukaasujen lämpöenergian sähköenergiaksi muuntavan mikro-ORC-energianmuuntimen suorituskyky. Suorituskyky pyrittiin toteamaan laskemalla laboratoriomittauksista saadusta datasta koelaitoksen sähköntuotannon hyötysuhde ja vertaamalla sitä mallinnuksessa laskettuun hyötysuhteeseen. Esitys käytännöstä suorituskyvyn todentamiseen kuuluu työn sisältöön. Koelaitoksen suorituskykyä ei pystytty toteamaan turbogeneraattoriin liittyvien ongelmien vuoksi. Tarkasteltavaksi tähän työhön jäi koelaitoksen suorituskykyyn olennaisesti liittyvien laitoskomponenttien toiminta niille tyypillisten mittausdatasta laskettujen tunnuslukujen kautta. Koelaitoksella käytettyjen lämmönsiirrinten todettiin olevan kykeneviä siirtämään tarpeeksi lämpöenergiaa 130 kW jarruteholla toimivan diesel-moottorin savukaasujen lämmöstä sähköenergian tuotantoon. Laitoksen kaupallistamista tarkasteltiin asiakkaan ja valmistajan näkökulmasta. Tarkasteluun sisältyi katsaus kaupalliseen versioon kuuluvista ominaisuuksista, alihankinnasta ja säädöksistä, jotka laitoksen on täytettävä markkinoille päästäkseen.

Uudella liiketoimintamallilla palloiluhalli menestykseen?

Tutkimuksen tarkoituksena on selvittää, voisiko uudella Keravan seudulle mahdollisesti rakennettavalla palloiluhallilla olla mahdollisuuksia erottautua kilpailijoistaan ja sitä kautta menestyä. Tutkimusta varten haastateltiin kolmea eri yritystä jotka toimivat eri puolella Suomea. Palloiluhalliyritykset tuottavat voittoa ja mahdollistavat toiminnan kehittämisen pitkällä aikavälillä. Liiketoimintamalleja ei kuitenkaan ole järjestelmällisesti mietitty, joten sitä kautta on saavutettavissa uusia mahdollisuuksia. Täydellisellä liiketoimintamallilla on mahdollista saada palloiluhalli vielä entistä paremmin tuottavaksi ja sitä kautta menestyväksi.

Operatiivinen säteilysuojelu Posivan kapselointi- ja loppusijoituslaitoksella

Olkiluodon ja Loviisan ydinvoimalaitoksilla syntyvä käytetty ydinpolttoaine tullaan kapseloimaan ja loppusijoittamaan Posiva Oy:n kapselointi- ja loppusijoituslaitoksella, joka rakennetaan Olkiluotoon. Käytetyn polttoaineen käsittelyssä on huomioitava säteilytyöhön liittyviä säteilysuojelunäkökohtia. Kapseloinnissa ja loppusijoituksessa käsitellään vaarallisia säteilylähteitä, joista merkittävimmät ovat käytetty ydinpolttoaine ja täyden loppusijoituskapselin röntgentarkastuslaitteisto. Posivan laitosten käyttötoiminnalle muodostetaan tässä diplomityössä säteilysuojelun vaatimusmäärittely. Kapseloinnin ja loppusijoituksen säteilytyövaiheet käsitellään yksitellen säteilysuojelun näkökulmasta. Työvaiheille määritetään tarpeelliset säteilysuojelutoimenpiteet ja työvaiheiden suorittamisen säteilysuojeluvaatimukset. Molempien laitosten valvonta-aluejärjestelyjä ja säteilyolosuhteiden vyöhykejakoa tarkennetaan. Työssä määritetään vyöhyke- ja aluerajoilla vaadittavat säteilysuojelutoiminnot sekä kontaminaationhallinnan laatuvaatimukset. Työssä käsitellään myös operatiivisen säteilysuojelun toimenpiteiden laatuvaatimuksia ja tarvittavaa säteilysuojelun sisäistä ohjeistoa. Työn tuloksena on kapselointi- ja loppusijoituslaitoksen käyttötoiminnan operatiivisten säteilysuojelutoimenpiteiden kuvaus. Kapselointi- ja loppusijoituslaitosten säteilysuojelua toteutetaan käyttövaiheen työnsuunnittelulla, operatiivisilla säteilysuojelutoimilla ja rakenteellisin keinoin. Työntekijöiden säteilyannokset minimoidaan välttämällä oleskelua kohonneen säteilytason alueilla. Kapselin röntgentarkastuslaitteiston käytön säteilyturvallisuus on varmistettava ja laitosten käyttötoiminta ei saa aiheuttaa työntekijöille sisäistä säteilyannosta. Useista työvaiheista ja käyttötoiminnan poikkeustilanteista on tehtävä jatkoanalyyseja työntekijöiden säteilysuojelun näkökulmasta.

Macroalgal Defenses Against Herbivory: Causes and Consequences of Intraspecific Variation

In marine benthic communities, herbivores consume a considerable proportion of primary producer biomass and, thus, generate selection for the evolution of resistance traits. According to the theory of plant defenses, resistance traits are costly to produce and, consequently, inducible resistance traits are adaptive in conditions of variable herbivory, while in conditions of constant/strong herbivory constitutive resistance traits are selected for. The evolution of resistance plasticity may be constrained by the costs of resistance or lack of genetic variation in resistance. Furthermore, resource allocation to induced resistance may be affected by higher trophic levels preying on herbivores. I studied the resistance to herbivory of a foundation species, the brown alga Fucus vesiculosus. By using factorial field experiments, I explored the effects of herbivores and fish predators on growth and resistance of the alga in two seasons. I explored genetic variation in and allocation costs of resistance traits as well as their chemical basis and their effects on herbivore performance. Using a field experiment I tested if induced resistance spreads via water-borne cues from one individual to another in relevant ecological conditions. I found that in the northern Baltic Sea F. vesiculosus communities, strength of three trophic interactions strongly vary among seasons. The highly synchronized summer reproduction of herbivores promoted their escape from the top-down control of fish predators in autumn. This resulted into large grazing losses in algal stands. In spring, herbivore densities were low and regulated by fish, which, thus,enhanced algal growth. The resistance of algae to herbivory increased with an increase in constitutive phlorotannin content. Furthermore, individuals adopted induced resistance when grazed and when exposed to water-borne cues originating from grazing of conspecific algae both in the laboratory and in field conditions. Induced resistance was adopted to a lesser extent in the presence of fish predators. The results in this thesis indicate that inducible resistance in F. vesiculosus is an adaptation to varying herbivory in the northern Baltic Sea. The costs of resistance and strong seasonality of herbivory have likely contributed to the evolution of this defense strategy. My findings also show that fish predators have positive cascading effects on F. vesiculosus which arise via reduced herbivory but possibly also through reduced resource allocation to resistance. I further found evidence that the spread of resistance via water-borne cues also occurs in ecologically realistic conditions in natural marine sublittoral. Thus, water-borne induction may enable macroalgae to cope with the strong grazing pressure characteristic of marine benthic communities. The results presented here show that seasonality can have pronounced effects on the biotic interactions in marine benthic communities and thereafter influence the evolution of resistance traits in primary producers.

John Marchese

John Marchese was an arts student and was the first Manager of the Brock Student Pub operated out of Alfie's Trough which was our first student center paid for by the students and built in 1969. It had its grand opening in 1970.

Village Expansion

Built in 1989, Village Residences added more units in 1992.

Arsenic speciation by ion-exchange chromatography with on- line determination by hydride generation: electronic modification of the D.C. plasma by photon counting

A method using L-cysteine for the determination of arsenous acid (As(III)), arsenic acid (As(V)), monomethylarsonic acid (MMAA), and dimethylarsinic acid (DMAA) by hydride generation was demonstrated. The instrument used was a d.c. plasma atomic emission spectrometer (OCP-AES). Complete recovery was reported for As(III), As(V), and DMAA while 86% recovery was reported for MMAA. Detection limits were determined, as arsenic for the species listed previously, to be 1.2, 0.8, 1.1, and 1.0 ngemL-l, respectively. Precision values, at 50 ngemL-1 arsenic concentration, were f.80/0, 2.50/0, 2.6% and 2.6% relative standard deviation, respectively. The L-cysteine reagent was compared directly with the conventional hydride generation technique which uses a potassium iodide-hydrochloric acid medium. Recoveries using L-cysteine when compared with the conventional method provided the following results: similar recoveries were obtained for As(III), slightly better recoveries were obtained for As(V) and MMAA, and significantly better recoveries for DMAA. In addition, tall and sharp peak shapes were observed for all four species when using L-cysteine. The arsenic speciation method involved separation by ion exchange .. high perfonnance liquid chromatography (HPLC) with on-line hydride generation using the L.. cysteine reagent and measurement byOCP-AES. Total analysis time per sample was 12 min while the time between the start of subsequent runs was approximately 20 min. A binary . gradient elution program, which incorporated the following two eluents: 0.01 and 0.5 mM tri.. sodium citrate both containing 5% methanol (v/v) and both at a pH of approximately 9, was used during the separation by HPLC. Recoveries of the four species which were measured as peak area, and were normalized against As(III), were 880/0, 290/0, and 40% for DMAA, MMAA and As(V), respectively. Resolution factors between adjacent analyte peaks of As(III) and DMAA was 1.1; DMAA and MMAA was 1.3; and MMAA and As(V) was 8.6. During the arsenic speciation study, signals from the d.c. plasma optical system were measured using a new photon-signal integrating device. The_new photon integrator developed and built in this laboratory was based on a previously published design which was further modified to reflect current available hardware. This photon integrator was interfaced to a personal computer through an AID convertor. The .photon integrator has adjustable threshold settings and an adjustable post-gain device.

Elements that contribute to staff nurses' commitment to lifelong professional development

This research explored the elements that contribute to staff nurses' commitment to lifelong professional development. This exploration has been undertaken to provide insights into those factors that motivate individuals to continue their education for professional development and for clinical practice improvement. This study was conducted in an acute care hospital in Southern Ontario, and investigated the thoughts and experiences ofhealth care staffworking within that setting. A qualitative case study was undertaken which involved the collection of interview, document, and class observation data. Two exemplary clinical nurse educators and two motivated, professionally committed staffnurses were interviewed during the study. Teaching document review and observation ofclasses involving the clinical nurse educators were conducted to facilitate triangulation of fmdingswith data sources and strategies. These participants provided rich data that were captured in field notes and coded for conceptual meaning. Emerging from the data were the identification ofthree major elements of influence that contribute to staffnurses' commitment to lifelong professional development. Identified within the three intersecting spheres of influence upon staff nurses' lifelong commitment to professionalleaming were the environment, the clinical nurse educator, and the staff nurse. This research explored the intersecting spheres of influence and the elements within the partnership model ofprofessional education for staff nurses.

Palaeopigment accumulation and implcations for paleolimnology over the lost century for two Ontario lakes

Crawford Lake is a meromictic lake, which is 24 m deep and has an area of 2.5 ha, and has never been reported to have mixed below 16 m. Lady Evelyn Lake, which became a reservoir when a dam was built in 1916, is dimictic with a maximum depth of about 35 m. 1 My research proved that both native chlorophylls and the ratio of chlorophyll derivatives to total carotenoids were better preserved in the shallower lake (Crawford Lake) because it was meromictic. Thus the anaerobic conditions in Crawford Lake below 16 m (monimolimnion) provide excellent conditions for pigment preservation. Under such conditions, the preservation of both chlorophylls and carotenoids, including oscillaxanthin and myxoxanthophyll, are extremely good compared with those of Lady Evelyn Reservoir, in which anaerobic conditions are rarely encountered at the mud-water interface. During the period from 1500 to 1900 A. D. in Crawford Lake, the accumulation rates of oscillaxanthin and myxoxanthophyll were extremely high, but those of chlorophyll derivatives and total carotenoids were relatively low. This was correlated with the presence of a dense benthic mat of cyanobacteria near the lake's chemocline. Competition for light between the deep dwelling cyanobacteria and overlying phytoplankton in this meromictic lake would have been intensified as the lake became more and more eutrophic (1955-1991 A. D.). During the period from 1955 to 1991 A. D., the accumulation rates of chlorophyll derivatives and total carotenoids in the sediment core from Crawford Lake (0-7.5 cm, 1955-present) increased. During this same period, the accumulation rates of cyanobacterial pigments (Le. oscillaxanthin and myxoxanthophyll) declined as the lake became more eutrophic. Because the major cyanobacteria in Crawford Lake are benthic mat forming Lyngbya and Oscillatoria and not phytoplankton, eutrophication resulted in a decline of the mat forming algal pigments. This is important because in previous palaeolimnological studies the concentrations of oscillaxanthin and myxoxanthophyll have been used as correlates with lake trophic levels. The results of organic carbon a13c analysis on the Crawford Lake sediment core supported the conclusions from the pigment study as noted above. High values of a13c at the depth of 34-48 cm (1500-1760 A. D.) were related to a dense population of benthic Oscillatoria and Lyngbya living on the bottom of the lake during that period. The Oscillatoria and Lyngbya utilized the bicarbonate, which had a high a 13C value. Very low values were found at 0-7 cm in the Crawford sediment core. At this time phytoplankton was the main primary producer, which enriched 12C by photosynthetic assimilation.

Rapid [Gamma]-amino acid synthesis and the inhibition of the growth and development of oblique banded leaf-roller larvae

The hypothesis that rapid y-aminobutyric acid (GABA) accumulation is a plant defense against phytophagous insects was investigated. Simulation of mechanical damage resulting from phytophagous insect activity increased soybean (Glycine max L.) leaf GABA 10- to 25-fold within 1 to 4 min. Pulverizing leaf tissue resulted in a value of 2. 15 (±O. 11 SE) ~mol GABA per gram fresh weight. Increasing the GABA levels in a synthetic diet from 1.6 to 2.6 Jlffiol GABA per gram fresh weight reduced the growth rates, developmental rates, total biomass (50% reduction), and survival rates (30% reduction) of cultured Oblique banded leaf-roller (OBLR) (Choristonellra rosacealla Harris) larvae. In field experiments OBLR larvae were found predominantly on young terminal leaves which have a reduced capacity to produce GABA in response to mechanical damage. Glutamate decarboxylase (GAD) is a cytosolic enzyme which catalyses the decarboxylation of L-Glu to GABA. GAD is a calmodulin binding enzyme whose activity is stimulated dramatically by increased cytosolic H+ or Ca2 + ion concentrations. Phytophagous insect activity will disrupt the cellular compartmentation of H+ and Ca2 +, activate GAD and subsequent GABA accumulation. In animals GABA is a major inhibitory neurotransmitter. The possible mechanisms resulting in GABA inhibited growth and development of insects are discussed.

Chapman Park Hotel, Wilshire Boulevard, Los Angeles, 1934.

Chapman Park Hotel, Wilshire Boulevard between Mariposa and Alexandria Avenue, Los Angeles, 1934. Formerly named the Alexandria Hotel, it was built in 1906 and enlarged in 1909. The Santa Ysabel Land Company, controlled by Charles C. Chapman and his son, Stanley Chapman, purchased the hotel in 1930. It housed the United States women for the 1932 Olympics in Los Angeles.

Chapman Park Hotel, Wilshire Boulevard, Los Angeles, 1934

Chapman Park Hotel, Wilshire Boulevard between Mariposa and Alexandria Avenue, Los Angeles, 1934. Formerly named the Alexandria Hotel, it was built in 1906 and enlarged in 1909. The Santa Ysabel Land Company, controlled by Charles C. Chapman and his son, Stanley Chapman, purchased the hotel in 1930. It housed the United States women for the 1932 Olympics in Los Angeles.