Feasibility study of submerged membrane bioreactor (MBR) as an alternative to conventional activated sludge process (CASP) for municipal wastewater treatment: A pilot scale study

The conventional activated sludge processes (CAS) for the treatment of municipal wastewater are going to be outdated gradually due to more stringent environmental protection laws and regulations. The Membrane bioreactors (MBRs) are the most promising modern technology widely accepted in the world of wastewater treatment due to their highly pronounced features such as high quality effluent, less foot print and working under high MLSS concentration. This research project was carried out to investigate the feasibility and effectiveness of MBR technology compare to the CAS process based on the scientific facts and results. The pilot scale MBR pilot plant was run for more than 150 days and the analysis results were evaluated. The prime focus of the project was to evaluate the correlation of permeate flux under different operating MLSS concentrations. The permeate flux was found almost constant regardless of variations in MLSS concentrations. The removal of micropollutant such as heavy metals, PCPPs, PFCs, steroidal hormones was also studied. The micropollutant removal performance of MBR process was found relatively effective than CAS process. Furthermore, the compatibility of submerged membranes within the bioreactor had truly reduced the process footprint.

The biotechnology of lactic acid bacteria with emphasis on applications in food safety and human health

Selostus: Terveyttä ja ruoan turvallisuutta edistävät maitohappobakteerien biotekniset sovellukset

Contribution of modern biotechnology of lactic acid bacteria to development of health-promoting foods

Selostus: Terveysvaikutteisten elintarvikkeiden tuottamista edesauttavat maitohappobakteerien molekyyligeneettiset tutkimukset

Phosphorus content of ditch sediments as indicator of critical source areas

Selostus : Kilpailukykyinen menetelmä pistemäisten fosforikuormitusalueiden paikantamiseen

Use of inoculated lactic acid bacteria in fermenting sour cabbage

Selostus: Maitohappobakteerien hyödyntäminen hapankaalin fermentoinnissa

Removal of Cadmium, Lead and Arsenic from Water by Lactic Acid Bacteria

A number of contaminants such as arsenic, cadmium and lead are released into the environment from natural and anthropogenic sources contaminating food and water. Chronic oral ingestion of arsenic, cadmium and lead is associated with adverse effects in the skin, internal organs and nervous system. In addition to conventional methods, biosorption using inactivated biomasses of algae, fungi and bacteria has been introduced as a novel method for decontamination of toxic metals from water. The aim of this work was to evaluate the applicability of lactic acid bacteria as tools for heavy metal removal from water and characterize their properties for further development of a biofilter. The results established that in addition to removal of mycotoxins, cyanotoxins and heterocyclic amines, lactic acid bacteria have a capacity to bind cationic heavy metals, cadmium and lead. The binding was found to be dependent on the bacterial strain and pH, and occurred rapidly on the bacterial surface, but was reduced in the presence of other cationic metals. The data demonstrates that the metals were bound by electrostatic interactions to cell wall components. Transmission electron micrographs showed the presence of lead deposits on the surface of biomass used in the lead binding studies, indicating involvement of another uptake/binding mechanism. The most efficient strains bound up to 55 mg Cd and 176 mg Pb / g dry biomass. A low removal of anionic As(V) was also observed after chemical modification of the cell wall. Full desorption of bound cadmium and lead using either dilute HNO₃ or EDTA established the reversibility of binding. Removal of both metals was significantly reduced when biomass regenerated with EDTA was used. Biomass regenerated with dilute HNO3 retained its cadmium binding capacity well, but lead binding was reduced. The results established that the cadmium and lead binding capacity of lactic acid bacteria, and factors affecting it, are similar to what has been previously observed for other biomasses used for the same purpose. However, lactic acid bacteria have a capacity to remove other aqueous contaminants such as cyanotoxins, which may give them an additional advantage over the other alternatives. Further studies focusing on immobilization of biomass and the removal of several contaminants simultaneously using immobilized bacteria are required.

Puhdistetun jäteveden patogeenit ja desinfiointitarve

Turun seudulla kuuden kunnan jätevesien käsittely keskitetään Kakolanmäen kallion sisälle rakennettuun jätevedenpuhdistamoon, joka otetaan käyttöön vuoden 2008 lopulla. Kakolanmäen jätevedenpuhdistamolla on varauduttu tulevaisuudessa kiristyviin lupaehtoihin sekä mahdollisiin puhdistetun jäteveden hygieenistä laatua koskeviin lisämääräyksiin jättämällä tilavaraus puhdistetun jäteveden desinfioimiselle ultraviolettivalolla. Diplomityössä on selvitetty vuoden kestäneessä tutkimusjaksossa 1.9.2006- 31.8.2007 Turun kaupungin keskuspuhdistamolta mereen johdetun puhdistetun jäteveden ja esiselkeytetyn ohitusveden hygieenisen laadun vaihtelua. Jäteveden desinfiointitarvetta on arvioitu tarkastelemalla jätevedenpuhdistamon hygieenistä puhdistustulosta ja jätevesien vaikutusta purkuvesistön hygieeniseen tilaan. Tutkimuksen perusteella virtaama ei vaikuttanut merkittävästi jäteveden ulosteperäisten bakteerien määriin. Sen sijaan jäteveden bakteeripitoisuudet laskivat alhaisissa lämpötiloissa. Lämpötilan vaikutus näkyi selkeämmin esiselkeytetyssä kuin puhdistetussa jätevedessä eli bakteerien poistumiseen aktiivilietevaiheen aikana vaikuttavat muut tekijät. Mitä tehokkaammin aktiivilietevaihe toimi, sitä tehokkaammin myös bakteereja poistui. Taudinaiheuttajabakteerit selvisivät puhdistusprosessista paremmin viileän kauden aikana. Puhdistetun jäteveden hygieeninen laatu ei täyttänyt uimaveden tai kasteluveden laatuvaatimuksia, joten desinfiointitarve olisi perustelua. Jätevesien vaikutus Turun edustan merialueen hygieeniseen tilaan näkyi ajoittain korkeina bakteeripitoisuuksina purkupaikan lähistöllä. Vielä ei ole suoraa näyttöä siitä aiheuttavatko jätevedet purkupaikan lähistön uimarannoilla terveydellisiä riskejä. Jäteveden UV-desinfiointi kannattava toteuttaa vain jos hygieeninen puhdistusvelvoite määrätään. UV-desinfioinnin mitoituksessa Kakolanmäen jätevedenpuhdistamolla tulee ottaa huomioon suurin sallittu hydraulinen painehäviö. Mitoitus voidaan tehdä puhdistamon käyttöönoton jälkeen kun tarvitut prosessimittaustiedot ovat saatavilla.

VIX as a stock market indicator

The goal of this research was to make an overall sight to VIX and how it can be used as a stock market indicator. Volatility index, often referred as the fear index, measures how much does it cost for investor to protect his/hers S&P 500 position from fluctuations with options. Over the relatively short history of VIX it has succesfull timing coordinator and it has told about the market state adding its own psychological view of the amount of fear and greed.

Targeting of caries prevention at preschool children, a practice based study

Aim and design: To evaluate an oral health program directed to expecting families and their children. The intervention was carried out in one of the four health care areas of the city of Turku. Another area acted as a control. Subjects and methods: Children (n = 1217), born between January 1, 1998 and June 30, 1999, in the respective health care areas were screened for mutans streptococci bacteria (MS), and their caretakers were interviewed when the child was 18 months old. MScolonization was used as the child’s risk indicator. Intensified health education and the use of xylitol lozenges targeted at the children at risk were the main elements of the program. Controls and the non-MS-colonized children received routine prevention –examination and education at the ages of three and five years. Altogether 794 subjects were followed for 42 months after receiving consent from their caretakers. Associations of oral-health-related factors with MS colonization and caries increment were studied inside the control group. Results: MS colonization associated with the occupation of the caretaker and ethnicity. The program was effective in white-collar families; prevented fraction being 67 %. In blue-collar families no effect was achieved. At the age of five years, caries increment was strongly related to the occupation of the caretaker, MS at 18 months, child’s sugar use, night feeding, use of thirst quencher at the age of 18 months, and father’s reported oral health. Conclusions: Programs targeted at MS-colonized children can reduce caries in whitecollar families. A program mainly based on activity at home seems to favor white-collar families, whereas different kind of support is needed for the blue-collar families.

Removal of cyanobacterial toxins by strains of probiotic bacteria

Nedbrytning av blågrönalgtoxiner med hälsobefrämjande mjölksyrebakterier Blomningar av cyanobakterier (blågrönalger) har blivit ett världsomfattande fenomen i eutrofierade vattenmiljöer. Cyanobakterier producerar toxiner, både levergifter och nervgifter, vilka utgör en hälsorisk för människan. Exponeringsrutter omfattar både dricksvatten och förorenade matvaror. Rening av dricksvatten från dessa toxiner är således av hög prioritet. Konventionella vatttenreningsprocesser är inte alltid tillräckligt effektiva mot cyanotoxiner. Därför behövs utveckling av nya effektiva biologiska metoder för vattenrening, vilka kunde komplettera de redan existerande metoderna. FM Sonja Nybom har i sin doktorsavhandling undersökt eliminering av cyanotoxiner från dricksvatten med hjälp av probioter. Probiotiska bakterier, såsom mjölksyrebakterier och bifidobakterier, finns i den naturliga tarmfloran och har även visats ha gynnsamma effekter för människans hälsa. I avhandlingen visades flera olika stammar av probiotiska mjölksyrebakterier och bifidobakterier effektivt eliminera cyanotoxiner, såsom levergiftiga microcystiner, från vatten. Elimineringen undersöktes under olika omständigheter och visades vara beroende av bland annat vattentemperatur, pH, celldensitet och närvaro av kolkälla (glukos) för bakterierna. Metaboliskt aktiva, levande bakterier krävdes för effektiv toxineliminering. En kombination av flera probiotstammar resulterade i effektivare nedbrytning av toxiner i jämförelse med enskilda bakteriestammar. Även reaktionstiden var av betydelse för effektiviteten; efter ett dygns inkubering åstadkoms nästan total nedbrytning. Sammanfattningsvis tyder resultaten på att metoder utnyttjande dessa hälsobefrämjande probiotiska bakterier kunde utvecklas till att användas vid rening av dricksvatten från cyanotoxiner samt användas som en personlig skyddsmekanism mot cyanotoxiner i mag-tarmkanalen.