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Concentrations of PBDE and BDE congeners in adipose tissue of East Greenland polar bears (Ursus maritimus)
2007
Dietz, Rune | Rigét, Frank F | Sonne, Christian | Letcher, Robert J | Backus, S | Born, Erik W | Kirkegaard, Maja | Muir, Derek C G
Polybrominated diphenyl ethers (PBDEs) were analysed in adipose tissue from 92 East Greenland polar bears (Ursus maritimus) sampled during 1999-2001. Mean SumPBDE concentrations were 70 ng/g lipid weight (lw) (range: 22-192 ng/g lw) and showed no relationship with age or sex. Of the 32 analysed PBDE congeners; BDE47, BDE153, BDE99 and BDE100 dominated, and comprised 99.6% of the SumPBDE concentration. The SumPBDE concentration had a highly significant correlation with SumPCB, SumCHL, dieldrin, HCB and SumHCH concentrations. We found a seasonal pattern of median SumPBDE concentration with 1.2 to 1.8 times higher concentrations in March to July than the rest of the year. The seasonal variation also provides a clue to the seasonal exposure, bio-availability, toxic exposure and degradation. We suggest that future geographical PBDE data comparisons may not need corrections for sex or age, but such data sets should be corrected for seasonal variability, using the presented correctional trigonometric regression.
Show more [+] Less [-]Artificial neural networks in vehicular pollution modelling
2007
Khare, Mukesh | Nagendra, S. M. Shiva
"Artificial neural networks (ANNs), which are parallel computational models, comprising of interconnected adaptive processing units (neurons) have the capability to predict accurately the dispersive behavior of vehicular pollutants under complex environmental conditions. This book aims at describing step-by-step procedure for formulation and development of ANN based VP models considering meteorological and traffic parameters. The model predictions are compared with existing line source deterministic/statistical based models to establish the efficacy of the ANN technique in explaining frequent dispersion complexities in urban areas. The book is very useful for hardcore professionals and researchers working in problems associated with urban air pollution management and control."--Jacket.
Show more [+] Less [-]Aerobic mesophylic bacteria in bottled waters
2007
Knezevic, P.,Prirodno-matematicki fakultet, Novi Sad (Serbia). Departman za biologiju i ekologiju | Petrovic, O.,Prirodno-matematicki fakultet, Novi Sad (Serbia). Departman za biologiju i ekologiju
There was carried out microbiological analysis of five bottled water of manufacturers from Serbia. Bacteriological quality was estimated using important parameter-aerobic mesophylic bacteria. Two nutrient media were used: standard (PCA) and low nutrient R2A. Plates were incubated at two temperatures (37 deg C and 22 deg C) during 24 hours, 48 hours, 3 days and 5 days. Results show that this group of bacteria is very abudant in bottled waters and their number depends on water types and manufacturers. Moreover, water from different bottles of the same manufacturer has different microbiological quality. Used media, temperatures and period of incubation also have influence on results and R2A medium gives higher values of aerobic mesophylic bacteria.
Show more [+] Less [-]Effects of the preozonation process on trihalomethanes and haloacetic acids precursors content in coagulated water
2007
Tubic, A.,Prirodno-matematicki fakultet, Novi Sad (Serbia) | Agbaba, J.,Prirodno-matematicki fakultet, Novi Sad (Serbia) | Dalmacija, B.,Prirodno-matematicki fakultet, Novi Sad (Serbia) | Watson, M.,Prirodno-matematicki fakultet, Novi Sad (Serbia) | Maletic, S.,Prirodno-matematicki fakultet, Novi Sad (Serbia) | Djurin, Z.,JKP Vodovod i kanalizacija, Zrenjanin (Serbia) | Pusic, I.,JKP Vodovod i kanalizacija, Zrenjanin (Serbia)
One of the biggest problems in drinking water treatment is the presence of a high natural organic matter (NOM) content in water resources. This paper presents the results of a study which aimed mainly to determine a combined coagulation and preozonization process application for trihalomethanes and haloacetic acids precursors content in ground water rich in natural organic matter.
Show more [+] Less [-]Automatic measuring stations for continuous water quality parameters monitoring on main waterstreams in Serbia
2007
Mijovic, S.,Republicki hidrometeoroloski zavod Srbije, Beograd (Serbia) | Palmar, B.,Republicki hidrometeoroloski zavod Srbije, Beograd (Serbia) | Stevanovic, S.,Republicki hidrometeoroloski zavod Srbije, Beograd (Serbia)
It is intended the build up of three automated measurement stations for continuous measurement of water quantity and quality parameters on the rivers Danube and Tisza: water level, temperature, pH, dissolved oxygen, conductivity, turbidity, ammonium ion concentration, nitrates concentration and chlorophyll a. The purpose of continuous measurement was to demonstrate the variability in time and space of the aquatic processes, as well as remote transfer of data to the centre. The large fluctuations of the data from discrete measurements illustrated the importance of continuous measurements for the complete description and modelling of the biological processes in the river.
Show more [+] Less [-]Distribution of seaweed Cystoseira barbata in the inner part of the Boka Kotorska bay [Montenegro]
2007
Macic, V.,Institut za biologiju mora, Kotor (Montenegro)
There are just a few data about species and quantities of phytobenthos for the Montenegrin coast, so that us one of the difficulties for the monitoring of changes caused by human impact. With the aim to contribute to the better knowledge of phytobenthos in this area we described distribution of Cystoseira barbata in the inner part of the Boka Kotorska bay and state of the environment in this aquatory.
Show more [+] Less [-]Phytoplankton situation in the inner part of Boka Kotorska bay [Montenegro]
2007
Vuksanovic, N.,Institut za biologiju mora, Kotor (Montenegro) | Krivokapic, S.,Prirodno-matematicki fakultet, Podgorica (Montenegro). Studijska grupa za biologiju | Regner, D.,Institut za biologiju mora, Kotor (Montenegro)
Influence of eutrophication to the phytoplankton community were studied in the inner part of Boka Kotorska Bay (Kotor Bay and Risan Bay) from September 2003 to August 2004. Kotor Bay and Risan Bay is very interesting area because the influence of natural and anthropogenic eutrophication are mixed very often. Microphytoplankton density is high (greater than 10**6 cells/cubic dm) what is characteristic eutrophic area, to the highest eutrophic area (greater than 10**7 cells/cubic dm). These values we stated in the surface, because in this layer were the best conditions. In same time we stated very high values: SiO2, oxygen saturation and chlorophyll a. The conclusion is: Boka Kotorska Bay and especially Kotor Bay (as a part of Boka Kotorska) has to be protected of dangerous consequences such as blooming. It is needed to regulate wastewater, their purification and permanent control physico-chemical and biological parameters, and especially phytoplankton component.
Show more [+] Less [-]Application of stable isotopes of nitrogen and oxygen in groundwater management
2007
Boreli-Zdravkovic, Dj.,Institut za vodoprivredu Jaroslav Cerni, Beograd (Serbia) | Miljevic, N.,Institut za nuklearne nauke Vinca, Beograd (Serbia)
In Serbia, in the most cases, drinking water supply is based on alluvial sources. The appearance of nitrate in some important alluvium aquifer has been observed and an increasing of this problem can be expected with a currently tendency for intensifying the agricultural production. Therefore, the used techniques which are able to identify the source of nitrate in groundwaters and existing processes of its reduction will be more and more requested. Simultaneously determination of both nitrogen and oxygen isotopic fingerprints allows us to make a difference between nitrate from artificial fertilizer and manure or animal waste as well as nitrate formed from nitrification of organic material and consequently the dominant source of the nitrate to be indicated. Once the origin of nitrate in drinking water sources is understood, corrective measures may be taken to prevent or minimize further contamination.
Show more [+] Less [-]Algological research of the Novo Ilje 1 and Novo Ilje 2 near Melenci (Vojvodina, Serbia)
2007
Fuzinato, S.,Univerzitet u Beogradu, Beograd (Serbia). Bioloski fakultet | Fodora, A.,Univerzitet u Beogradu, Beograd (Serbia). Bioloski fakultet | Subakov-Simic, G.,Univerzitet u Beogradu, Beograd (Serbia). Bioloski fakultet | Krizmanic, J.,Univerzitet u Beogradu, Beograd (Serbia). Bioloski fakultet
The puddles Novo Ilje 1 and Novo Ilje 2 are aquatic ecosystems periodically filled with moderate salt and alkaline water. In 2003 and 2004 quantitative analysis show the Euglenophyta domination. Trachelomonas taxa are the most common. The algae in planktonic communities are the most numerous in both puddles in researched years.
Show more [+] Less [-]Impact of hydromorphological alterations on ecological status of nature park Ponjavica [Serbia]
2007
Trifunov, S.,Prirodno-matematicki fakultet, Novi Sad (Serbia) | Planojevic, I.,Prirodno-matematicki fakultet, Novi Sad (Serbia) | Jurca, T.,Prirodno-matematicki fakultet, Novi Sad (Serbia) | Nemes, K.,Prirodno-matematicki fakultet, Novi Sad (Serbia) | Teodorovic, I.,Prirodno-matematicki fakultet, Novi Sad (Serbia)
Ecological status of protected area of Ponjavica water body, evaluated using hydromorphological, basic physico-chemical and selected biological quality elements, can be indicated as very bad. The accerelated eutrophication process this water body (once running now stragnant water) undergoes, leads to hypereutrophic current condition, with clear trend towards dystrophy.
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