Occurrence and elimination of cyanobacterial toxins in two Australian drinking water treatment plants

In Australian freshwaters, Anabaena circinalis, Microcystis spp. and Cylindrospermopsis raciborskii are the dominant toxic cyanobacteria. Many of these Surface waters are used as drinking water resources. Therefore, the National Health and Medical Research Council of Australia set a guideline for MC-LR toxicity equivalents of 1.3 mug/l drinking, water. However, due to lack of adequate data, no guideline values for paralytic shellfish poisons (PSPs) (e.g. saxitoxins) or cylindrospermopsin (CYN) have been set. In this spot check. the concentration of microcystins (MCs), PSPs and CYN were determined by ADDA-ELISA, cPPA, HPLC-DAD and/or HPLC-MS/MS, respectively, in two water treatment plants in Queensland/Australia and compared to phytoplankton data collected by Queensland Health, Brisbane. Depending on the predominant cyanobacterial species in a bloom, concentrations of up to 8.0, 17.0 and 1.3 mug/l were found for MCs, PSPs and CYN, respectively. However, only traces (< 1.0 mug/l) of these toxins were detected in final water (final product of the drinking water treatment plant) and tap water (household sample). Despite the low concentrations of toxins detected in drinking water, a further reduction of cyanobacterial toxins is recommended to guarantee public safety. (C) 2004 Elsevier Ltd. All rights reserved.

Rayleigh noise mitigation in DWDM LR-PONs using carrier suppressed subcarrier-amplitude modulated phase shift keying

We demonstrate a novel Rayleigh interferometric noise mitigation scheme for applications in carrier-distributed dense wavelength division multiplexed (DWDM) passive optical networks at 10 Gbit/s using carrier suppressed subcarrier-amplitude modulated phase shift keying modulation. The required optical signal to Rayleigh noise ratio is reduced by 12 dB, while achieving excellent tolerance to dispersion, subcarrier frequency and drive amplitude variations.

More lr saturated L∞ spaces

2000 Mathematics Subject Classification: 05D10, 46B03.

Reach extension of high-capacity LR-PONs in chain configuration of distributed amplifier structure

We show 100-Gb/s single-channel transmission in LR-PONs with at least 512 way split and up to 160 km total distance is feasible by means of "chained" cable with amplifier solutions, and appropriate FIR filter designs. © 2015 OSA.

Quantitative Analysis and Determination of Microcystin in water by Capillary Electrophoresis Mass Spectrometry

The presence of harmful algal blooms (HAB) is a growing concern in aquatic environments. Among HAB organisms, cyanobacteria are of special concern because they have been reported worldwide to cause environmental and human health problem through contamination of drinking water. Although several analytical approaches have been applied to monitoring cyanobacteria toxins, conventional methods are costly and time-consuming so that analyses take weeks for field sampling and subsequent lab analysis. Capillary electrophoresis (CE) becomes a particularly suitable analytical separation method that can couple very small samples and rapid separations to a wide range of selective and sensitive detection techniques. This paper demonstrates a method for rapid separation and identification of four microcystin variants commonly found in aquatic environments. CE coupled to UV and electrospray ionization time-of-flight mass spectrometry (ESI-TOF) procedures were developed. All four analytes were separated within 6 minutes. The ESI-TOF experiment provides accurate molecular information, which further identifies analytes.

Skolan i livet - livet i skolan : Några illitterata invandrarkvinnor lär sig tala, läsa och skriva på svenska som andraspråk

Many immigrants in Sweden have not had the chance to learn to read and write, for various reasons. In Sweden, literacy is a prerequisite to being able to function in the cultural community, and for many immigrants this is the first time that they experience their inability to read and write as a handicap or see themselves as “illiterate”. The aim of this study is to use a socio-cultural, second language and gender approach to describe, analyse and understand how a number of adult, illiterate, immigrant women experience their situation when they are expected to simultaneously learn to speak, read and write Swedish. The study focuses on two literacy groups in two Swedish municipalities. In one of the groups I act as both teacher and researcher. The thesis is a case study of the learning process of five illiterate immigrant women in Sweden. The results are based on interviews, carried out with the help of an interpreter, and observation of teaching and texts ritten by the students. The study is based on the assumption that human learning is an activity that takes place in a cultural community in a social context. When learning a language, the language is simultaneously the tool that facilitates social communication and the object of the learning process. The study shows that cultural communities influence the women in different ways. Gender structures are firmly planted in a patriarchal value system, which means that women are seen as inferior to men, and women are expected to “meet the demands of others”. The women have no time to study at home, as their household duties are prioritised. However, there are subtle indications that there is a wish to change the situation in accordance with Swedish values and norms. This can be seen in the Swedish for Immigrants (SFI) lessons. As they have little contact with Swedes, school is the only arena in which they have a chance to use Swedish. They are positive towards teaching and school as an institution. Here they are able to develop an alternative identity. The study also shows that teaching in the literacy groups is to a great extent based on a technical approach, in which the teacher tries to elicit a correct answer from the students. Social interaction involving contemplation and negotiation is either not included or not prioritised. the women’s experience and knowledge is not made use of. There are,however, occasions when collaborative discussions take place between the teacher and students. On these occasions an exchange of experiences takes place. Learning is based on the students’ own experiences and thoughts. Linguistic concepts gain meaning in the collaborative discussion. Initially the concepts may be unclear, but the group works on them together, adapting and adjusting them until they finally make sense. Finally, I conclude that women immigrants bring their own socio-cultural values and experience to the school situation, which affects their learning process to varying degrees. Furthermore, immigrant women need more time at school, as it is the only arena in which they can spend time on studying and personal development. another conclusion is that the school must become a learning community that recognises the immigrants’ cultures, makes use of the students’ experience and allows the students to participate in collaborative discussions, so that they can develop their ability to speak, read and write Swedish.

Alla lär sig något? - Teori möter praktiskt yrkeskunnande

Abstract Akademisk yrkesutbildning ställer särskilda krav på såväl studerande som lärare. I Socionomutbildningen fokuseras på teoretiska perspektiv med användningsbarhet i en praxis som den studerande ska förberedas för och förstå. Dessutom ska en bedömning göras av såväl yrkesrelaterat, som teoretiskt kunnande, hos enskild studerande. Yrkesutbildning som akademisk utbildning innebär många utmaningar där det ibland kan uppstå problem. Syftet med detta paper har varit att beskriva förändringar genomförda i kursmomentet Åldrandets villkor, i socionomprogrammets socialgerontologikurs våren 2012, samt att belysa svårigheter med att bedöma den studerandes kunskaper då studerande har rätt till anonymitet i tentamen, tillika med att läraren inte får kräva obligatorisk närvaro. Texten avser att beskriva genomförandet av ett förändrat kursmoment som kallats Åldrandets villkor.  Detta kursmoment reflekteras dessutom som ett exempel på underlag för bedömningen av de studerandes insatser. Resultatet visade att det förändrade pedagogiska arbetssättet med momentet uppskattades av de flesta studerande. Men frågor kvarstår om hur man skapar underlag för en rättvis bedömning av de studerandes kunskaper och förmågor utifrån lärandemålen för just detta delmoment. Avslutningsvis reflekteras över hur svårt det är att finna bra bedömningsverktyg i kurser som avser skapa förutsättningar för såväl praktiskt yrkeskunnande, som ett teoretiskt reflekterande. Medverkan av praktiker i utbildningen kan vara ett redskap för att sammanfläta teori med praxis.

Interação da cianotoxina microcistina e o nanomaterial de carbono fulereno (C60) em brânquias do peixe Cyprinus carpio (Teleostei: Cyprinidae) sob incidência de radiação UVA

A produção mundial de nanomateriais tem aumentado nos últimos anos, em função de suas variadas aplicações tecnológicas e, como consequência do seu crescente uso e demanda, poderão existir riscos ambientais sendo a água o ambiente onde muitas destas substâncias podem exercer efeitos deletérios. Um dos nanomaterias de carbono mais utilizados é o fulereno, um composto orgânico lipofílico que pode se comportar como carreador de moléculas tóxicas, potencializando a entrada de contaminantes ambientais em órgãos específicos, fenômeno conhecido como “cavalo de Troia”. As microcistinas (MC) são cianotoxinas produzidas por cianobactérias durante episódios de floração, afetando aos organismos aquáticos e ao ser humano. Diversos estudos demonstram que organismos expostos tanto às MCs quanto ao fulereno podem causar produção excessiva de espécies ativas de oxigênio e alterar os níveis de antioxidantes. Além disso, outro fator que pode vir a intensificar o potencial tóxico de ambos é a incidência de radiação UVA. Sendo assim, procurou-se avaliar os efeitos em parâmetros de estresse oxidativo da co-exposição ex vivo da cianotoxina microcistina-LR (MC-LR) e o nanomaterial de carbono fulereno em brânquias do peixe Cyprinus carpio sob incidência de radiação UVA. Os resultados mostraram que: (a) houve uma perda da capacidade antioxidante no tratamento com MC-LR (baixa concentração) quando coexposta com fulereno no UVA em relação com o tratamento realizado sem co-exposição com fulereno; (b) o fulereno no UV diminuiu a atividade da enzima glutationa-Stransferase (GST) quando comparado com o controle no UV; (c) a MC-LR (alta concentração) co-exposta com fulereno foi capaz de diminuir as concentrações do antioxidante glutationa (GSH) quando comparado com o mesmo tratamento tanto no UVA quanto no escuro sem a co-exposição ao fulereno; (d) o tratamento MC-LR (baixa concentração) com UVA aumentou o dano oxidativo lipídico quando comparado com o controle UVA; (e) o fulereno não causou uma maior bioacumulação da microcistina no tecido. Sendo assim, pode-se concluir que o fulereno não apresentou o potencial de carregador de moléculas nessas concentrações de microcistina, porém, a co-exposição dos compostos diminuem tanto capacidade antioxidante total, como a concentração da GSH, podendo gerar problemas a longo prazo na detoxificação da toxina.

Applications of perceptron techniques to the submarine classification problem. Policy agreement project no. 208-LR-40. Combined progress and final report. Period: 1 June 1961 to 1 June 1962.

Cover title.

Cyanobacteria and Cyanotoxin in the Billings Reservoir (São Paulo, SP, Brazil)

The Billings Complex and the Guarapiranga System are important strategic reservoirs for the city of São Paulo and surrounding areas because the water is used among other things, for the public water supply. They produce 19,000 liters of water per second and Supply water to 5.4 million people. Crude water is transferred from the Taquacetuba branch of the Billings Complex to the Guarapiranga Reservoir to regulate the water level of the reservoir. The objective of this study was to evaluate the water quality in the Taquacetuba branch, focusing on cyanobacteria and cyanotoxins. Surface water samples were collected in February (summer) and July (winter) of 2007. Analyses were conducted of physical, chemical, and biological variables of he water, cyanobacteria richness and density, and the presence of cyanotoxins. The water was classified as eutrophic-hypereutrophic. Cyanobacteria blooms were observed in both collection periods. The cyanobacteria bloom was most significant in July, reflecting lower water transparency and higher levels of total solids, suspended organic matter, chlorophyll-a, and cyanobacteria density in the surface water. Low richness and elevated dominance of the cyanobacteria were found in both periods. Cylindrospermopsis raciborskii was dominant in February, with 352 661.0 cel mL(-1), and Microcystis panniformis was dominant in July, with 1 866 725.0 cel mL(-1). Three variants of microcystin were found in February (MC-RR, MC-LR, MC-YR), as well as saxitoxin. The same variants of microcystin were found in July, but no saxitoxin was detected. Anatoxin-a and cylindropermopsin were not detected in either period. These findings are of great concern because the water in the Taquacetuba branch, which is transferred into the Guarapiranga Reservoir, is not treated nor managed. It is recommended that monitoring be intensified and more effective measures be taken by the responsible agencies to prevent the process of eutrophication and the consequent development of the cyanobacteria and their toxins.

Leva som man lär? : En studie av spänningsfältet mellan genusvetande och genusgörande

Practice as you preach? Gender scholars’ reflections on practising gender theory Being a gender scholar – to what extent is it possible to practice as you preach? This study investigates how gender scholars relate to using and practicing theoretical knowledge on gender.Ten in-depth interviews are conducted with gender scholars at Swedish universities. A semi-structured interview guide, based on ambitions, possibilities and obstacles regarding using theoretical knowledge in practice, is used. The results indicate that being a gender scholar is a highly reflective project, since it involves turning your gender theoretical gaze towards yourself. Practicing as you preach seems to be interpreted as undoing gender. Attempts to undo gender are said to be hindered by gender normative structures rendering gender scholar women and gender scholar men different possibilities to practice the undoing of gender. The analysis show that gender scholars perform a balancing act by adding some expressions for the opposite gender to their everyday doings and their physical appearance, thus combining a doing with an undoing of gender. The pace and force of change in these doings and undoings are rather small. Nevertheless, small as they may be, these steps are interpreted as part of a strategy to change gender normative structures, making possible yet other and freer gender performances.