The evolution of the eutrophication of the Palić Lake (Serbia)

Eutrophication is a world-wide environmental issue. The Palic Lake is a shallow lake typical for the Pannonian plain. The Lake itself was in a very bad condition during the late sixties of the last century; polluted and hypertrophic. Due to inadequate water quality, it was dried out in 1971 and re-established in 1977 and since then its trophicity has been worsening. The lake has recreational purposes but it is also a collector for treated municipal waste waters coming from the lagoons for active sludge water treatment. The sewage discharges from rapidly developing towns in the watershed and the growing use of fertilizers in agriculture increased the nutrient load to the Lake in the last decades. A steady increase of phosphorus loading is the most important factor of the lake  eutrophication. The result of the accelerated eutrophication is the enormous amount of sediment at the bottom of the Palic Lake. Therefore, in the lake that covers an area of 565 ha and volume of 10 million m3, there was 1.900.160 m3 of sediment. The sediment thickness varied from 0.3 to 1.2 m. In summer 2010, the recreational part of the lake (sector IV) was 1.311.356 m3 of sediment, characterized with concentrations of total phosphorus (TP) of 2885 mg/kg, 4300 mg/kg total nitrogen (TN) and 39000 mg/kg total organic carbon TOC. The sediment of the Palic Lake was not loaded with high concentrations of heavy metals. Everything mentioned supports the fact that the restoration of this aquatic system is necessary and applied measures have to be grounded on the principles of ecoremediation technologies.Key words: Eutrophication, Palic Lake, sediment, total N, total P

Isolation of chromium resistant bacteria from a former bauxite mine area and their capacity for Cr (VI) reduction

The Cr (VI) reducing capacity of bacteria has been investigated in many different soils and waters but little or no information is available from soils originating from bauxite mine areas. From soil, mud and rhizospheres of the floating aquatic plant Potamogeton natans L. and the terrestrial plant Carduus acanthoides L., the Cr content was determined and the microbial populations were sampled. The highest total chromium concentration (204.6 mgkg-1) was found in the rhizosphere of C. acanthoides. To determine the numbers and percentages of chromate-resistant bacteria, the autochthonous microbial populations were subjected to different Cr (VI) concentrations (40, 100, 300 and 1000 mM as K2Cr2O7). At 1000 mM Cr (VI) in the medium, about 25% of bacteria from soil and 45% of bacteria from the rhizospheres were resistant. Of 34 bacterial isolates, within 24 h, only Bacillus stearothermophilus 12 ms, Pseudomonas sp. 12 bk3 and Serratia fonticola 7 be were able to reduce 50 μM Cr (VI). Using prolonged 72 h incubation, they were able to reduce 500 μM Cr (VI) concentrations added to the medium. These chromate-resistant bacteria isolated from rhizosphere of plants growing in bauxite mine soil have great potential for bioremediation of Cr (VI)-polluted wastes.Key words: Chromate-resistant bacteria, chromate reduction, bauxite mine, rhizosphere, plant

Polyphenolic Characterisation of Vranac, Kratosija and Cabernet Sauvignon (Vitis vinifera L. cv.) Grapes and Wines from Different Vineyard Locations in Montenegro

In Montenegro, red wines are produced predominantly, and Vranac accounts for nearly 80% of thesewines, followed by Kratosija and Cabernet Sauvignon. In order to characterise polyphenols in red varieties,grapes were sampled from representative vineyards at harvest time during 2011 and 2012. The contentand distribution of extractable anthocyanins, low-molecular mass proanthocyanidins (LMP) and highmolecularmass proanthocyanidins (HMP) in the seeds and skins of the grape berries were evaluated byapplying a five-day extraction method using ethanol:water (12:88) as extraction solvent. On average, thehighest content of LMP (2 006 and 1 690 mg/kg of grape fresh mass in years 2011 and 2012 respectively),HMP (2 705 and 2 805 mg/kg in years 2011 and 2012 respectively) and anthocyanins (1 035 mg/kg in theyear 2011) was found in the Cabernet Sauvignon grapes. The highest content of anthocyanins (1 113 mg/kgin the year 2012) and the lowest content of LMP (1 103 and 846 mg/kg in years 2011 and 2012 respectively)was found in Vranac grapes. Kratosija grapes had the lowest anthocyanin content (456 and 517 mg/kg inyears 2011 and 2012 respectively), and levels of LMP were similar to Vranac. The percentage distributionsof LMP between skins and seeds were 34:66, 39:61 and 49:51, whereas the distributions of HMP betweenskins and seeds were 67:33, 62:38 and 64:36 for Vranac, Kratosija and Cabernet Sauvignon respectively.All varieties had more LMP in the seeds and more HMP in the skins of the grapes. The results obtained areimportant to better understand the polyphenolic potential of Montenegrin red grape varieties

Forward pi^0 Production and Associated Transverse Energy Flow in Deep-Inelastic Scattering at HERA

Deep-inelastic positron-proton interactions at low values of Bjorken-x down to x \approx 4.10^-5 which give rise to high transverse momentum pi^0 mesons are studied with the H1 experiment at HERA. The inclusive cross section for pi^0 mesons produced at small angles with respect to the proton remnant (the forward region) is presented as a function of the transverse momentum and energy of the pi^0 and of the four-momentum transfer Q^2 and Bjorken-x. Measurements are also presented of the transverse energy flow in events containing a forward pi^0 meson. Hadronic final state calculations based on QCD models implementing different parton evolution schemes are confronted with the data.Comment: 27 pages, 8 figures and 3 table

Search for Doubly-Charged Higgs Boson Production at HERA

A search for the single production of doubly-charged Higgs bosons H^{\pm \pm} in ep collisions is presented. The signal is searched for via the Higgs decays into a high mass pair of same charge leptons, one of them being an electron. The analysis uses up to 118 pb^{-1} of ep data collected by the H1 experiment at HERA. No evidence for doubly-charged Higgs production is observed and mass dependent upper limits are derived on the Yukawa couplings h_{el} of the Higgs boson to an electron-lepton pair. Assuming that the doubly-charged Higgs only decays into an electron and a muon via a coupling of electromagnetic strength h_{e \mu} = \sqrt{4 \pi \alpha_{em}} = 0.3, a lower limit of 141 GeV on the H^{\pm\pm} mass is obtained at the 95% confidence level. For a doubly-charged Higgs decaying only into an electron and a tau and a coupling h_{e\tau} = 0.3, masses below 112 GeV are ruled out.Comment: 15 pages, 3 figures, 1 tabl

Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum