Water Quality Management in the Nitra River Basin

The Nitra River is a tributary of the Vih which enters the Danube downstream of Bratislava. The watershed area is slightly larger than 5000 km2, and more than 650000 inhabitants live there. The quality of the river is one of the poorest in Slovakia due to numerous municipal and industrial discharges and the low level of wastewater treatment. The ongoing economic transition and shortage of financial resources for environmental management call for the development of regional short-run, least-cost policies. The development of such policies was the main objective of this joint study with the participation of IIASA, the Water Research Institute (VUVH, Bratislava) and the Vih River Basin Authority. The present state of emissions and water quality was evaluated on the basis of available, routine types of information (including observations from the basin-wide water quality monitoring network) and additional data collection. It was found that industrial discharges form problems which can be handled mostly locally with a straight-forward strategy. In contrast, the management of municipal discharges -- representing about 70% of the total BOD5 emission in the catchment -- is a more complex issue requiring the development of a regional policy. The definition of ambient water quality criteria (or the usage of a combination of ambient and effluent criteria) reflecting water use is a pre-requisite of the establishment of a least-cost policy. Thus, the application of water quality models is necessary to relate emissions to receiving water quality (as well as their changes). Due to the nature of the problem, a number of oxygen and nutrient balance models were used, ranging from the traditional Streeter-Phelps model to the latest version of U.S. EPA's QUAL model family. The models were calibrated and validated on the basis of two comprehensive longitudinal water quality profile observations. These observations were gathered under low-flow conditions to correspond with the design requirements of the strategy development. Due to the presence of uncertainties of different origins, the methodology of Hornberger, Spear, and Young (based on the so-called "behavior definition") was applied for parameter estimation of simpler models which then were directly incorporated into an optimization model. This optimization model was based on dynamic programming, utilizing structural features of river basin water pollution problems. Elements of the water quality control policy model or decision support system (including the linked hydraulic and water quality model(s), the parameter estimation and uncertainty analysis routines, the dynamic programming, the database, the graphical user-interface, etc.) were developed in a rather generic fashion to allow a transfer from one watershed to another. This philosophy corresponds to the broader goals of IIASA's Water Resources Project dealing with issues of the management of degraded river basins in Central and Eastern Europe and the development of associated methodologies for which the Nitra River served as a case study. Starting from the existing municipal wastewater treatment facilities, a number of alternatives were developed for each site on the basis of various combinations of well-proven physical, biological, and chemical processes to which different effluent quality (BOD-5, TP, NH4-N, NO3-N, etc.) as well as investment, operation, maintenance, and repair costs belong. The technological alternatives (and their major parameters) serve as input to the management optimization model. A special focus was devoted to phased plant development and innovative, cost-effective upgrading of highly overloaded plants by adding chemicals in low dosage. The issue of upgrading was also experimentally analyzed by jar tests at different treatment plants. The objectives of the policy model were formulated in terms of minimizing the total annual cost or the investment cost. Constraints might incorporate ambient water quality (characterized by DO, BOD-5 and NH4-N), effluent criteria, and/or minimum level of treatment. The derived least-cost policies were compared to policies based strictly on effluent criteria and to those based on the application of "best available technology." The effluent criteria based policy stems from the new Slovakian legislation if its ambient criteria element was excluded (the legislation defines the simultaneous usage of effluent and ambient criteria and an eleven-year long transition period after which more stringent standards should be met). The role of industrial emissions was demonstrated in a sensitivity fashion, while the influence of parameter uncertainty on the developed policies was analyzed by an a posteriori Monte Carlo simulation and a multi-objective assessment. The study shows that significant cost savings are possible in comparison to uniform, effluent standard policies. They also suggest that a long-term strategy should be realized on the basis of a sequence of properly phased least-cost policies corresponding to ambient (or regionally variable) standards to be tightened gradually as financial resources become available

Longitudinal Water Quality Profile Measurements and their Evaluation in the Nitra River basin (Slovakia)

The Nitra River is one of most polluted rivers in the Slovak Republic, due to numerous industrial and municipal emissions, and low level of wastewater treatment. Policy-oriented water quality management study on the basin was undertaken jointly by IIASA, the Water Research Institute in Bratislava (VUVH), and the Vah River Basin Authority. One of the components of the research were the water quality profiles experiments incorporating both emission and river water sampling, followed by an analysis with mass balance method. Two experiments were performed in the basin, in August 1992 and June 1993, respectively. The first experiment was focused on the "conventional" water quality parameters affecting dissolved oxygen balance, such as BOD, COD and nitrogen. The second, although limited only to certain regions of the basin, was aimed at understanding more detailed water quality processes in the river such as sedimentation and hydrolysis of organic material. Rough estimates of the process rates were obtained with mass balance method. The results of the work were used for calibration of water quality models essential for the formulation of economically feasible wastewater treatment policy in the basin based on water quality criteria

Critical magnetic fluctuations induced superconductivity and residual density of states in CeRhIn5CeRhIn_5 superconductor

We propose the multiband extension of the spin-fermion model to address the superconducting d-wave pairing due to magnetic interaction near critical point. We solve the unrestricted gap equation with a general d-wave symmetry gap and find that divergent magnetic correlation length $\xi$ leads to the very unharmonic shape of the gap function with shallow gap regions near nodes. These regions are extremely sensitive to disorder. Small impurity concentration induces substantial residual density of states. We argue that we can understand the large $N_{res}(0) = \lim_{T\to 0} C_p(T)/T$ value and its pressure dependence of the recently discovered $CeRhIn_5$ superconductor under pressure within this approach.Comment: 5 figure

Dysfunctional telomeres in primary cells from Fanconi anemia FANCD2 patients

© 2012 Joksic et al. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.This article has been made available through the Brunel Open Access Publishing Fund.Background: Fanconi anemia (FA) is characterized by sensitivity to DNA cross-linking agents, mild cellular, and marked clinical radio sensitivity. In this study we investigated telomeric abnormalities of non-immortalized primary cells (lymphocytes and fibroblasts) derived from FA patients of the FA-D2 complementation group, which provides a more accurate physiological assessment than is possible with transformed cells or animal models. Results: We analyzed telomere length, telomere dysfunction-induced foci (TIFs), sister chromatid exchanges (SCE), telomere sister chromatid exchanges (T-SCE), apoptosis and expression of shelterin components TRF1 and TRF2. FANCD2 lymphocytes exhibited multiple types of telomeric abnormalities, including premature telomere shortening, increase in telomeric recombination and aberrant telomeric structures ranging from fragile to long-string extended telomeres. The baseline incidence of SCE in FANCD2 lymphocytes was reduced when compared to control, but in response to diepoxybutane (DEB) the 2-fold higher rate of SCE was observed. In contrast, control lymphocytes showed decreased SCE incidence in response to DEB treatment. FANCD2 fibroblasts revealed a high percentage of TIFs, decreased expression of TRF1 and invariable expression of TRF2. The percentage of TIFs inversely correlated with telomere length, emphasizing that telomere shortening is the major reason for the loss of telomere capping function. Upon irradiation, a significant decrease of TIFs was observed at all recovery times. Surprisingly, a considerable percentage of TIF positive cells disappeared at the same time when incidence of γ-H2AX foci was maximal. Both FANCD2 leucocytes and fibroblasts appeared to die spontaneously at higher rate than control. This trend was more evident upon irradiation; the percentage of leucocytes underwent apoptosis was 2.59- fold higher than that in control, while fibroblasts exhibited a 2- h delay before entering apoptosis. Conclusion: The results of our study showed that primary cells originating from FA-D2 patients display shorten telomeres, elevated incidence of T-SCEs and high frequency of TIFs. Disappearance of TIFs in early response to irradiation represent distinctive feature of FANCD2 cells that should be examined further.This article is made available through the Brunel Open Access Publishing Fund. This work was supported by the Ministry of Education and Science of the Republic of Serbia (Project No.173046)

Long Term Functional and Esthetic Outcomes After Fibula Free Flap Reconstruction of the Mandible

Objectives: To report functional and esthetic outcomes, after fibula free flap (FFF) reconstruction of the mandible for oral cancer, assessed by physicians, non-clinicians and patients. Materials and Methods: Twenty-five long term survivors from oral cancer after FFF reconstruction were recalled for head and neck examination by surgeons and patient reported outcomes, using EORTC, QLQ C-30, H&N-35 and FACE-Q questionnaires. Results: Physicians reported 64% restoration of functionality compared to normal. Patients reported high scores on QLQ-C30, but lower scores on H&N-35. Esthetic scores were reported higher by clinicians than non-clinicians. The decline in function and appearance was attributed to loss of lower dentition, trismus, mal occlusion, xerostomia and tissue atrophy. Conclusion: To minimize the decline in function and appearance, immediate dental implants in FFF, better reconstruction of the temporomandibular joint, newer methods of radiotherapy to minimize xerostomia and oral exercises to prevent trismus should be considered

Degenerate quantum gases manipulation on AtomChips

The integration of cold atomic sources and electromagnetic field sources in the same device is a major frontier for both fundamental science and advanced technology. In this paper, we discuss the realization of the Bose-Einstein condensate (BEC) on an AtomChip and describe such an experimental configuration realized at LENS. We also concentrate on the realization of a particular integrated matter wave interferometer where coherent coupling between the BECs in different Zeeman states is used to produce a fringe time-population signal at the output. Finally, we discuss the prospects for application of such a device as a multi-path interferometer. 3rd International School and Conference on Photonics, Aug 29-Sep 02, 2011, Belgrade, Serbi

The mechanism of caesium intercalation of graphene

Properties of many layered materials, including copper- and iron-based superconductors, topological insulators, graphite and epitaxial graphene can be manipulated by inclusion of different atomic and molecular species between the layers via a process known as intercalation. For example, intercalation in graphite can lead to superconductivity and is crucial in the working cycle of modern batteries and supercapacitors. Intercalation involves complex diffusion processes along and across the layers, but the microscopic mechanisms and dynamics of these processes are not well understood. Here we report on a novel mechanism for intercalation and entrapment of alkali-atoms under epitaxial graphene. We find that the intercalation is adjusted by the van der Waals interaction, with the dynamics governed by defects anchored to graphene wrinkles. Our findings are relevant for the future design and application of graphene-based nano-structures. Similar mechanisms can also play a role for intercalation of layered materials.Comment: 8 pages, 7 figures in published form, supplementary information availabl

‘The International Teacher Leadership project,’ a case of international action research.

Copyright CARNThe paper arises from the International Teacher Leadership project, a research and development project involving researchers and practitioners in 14 European countries. The paper provides a conceptual exploration of the idea of teacher leadership and its role in educational reform, central to which is the idea that teachers, regardless of their level of power and organisational position, can engage in the leadership of enquiry-based development activity aimed at influencing their colleagues and embedding improved practices in their schools. The paper provides an outline of the project’s methodology which builds on that used in the Carpe Vitam Leadership for Learning project (Frost, 2008a). It is a form of collaborative action research which is highly developmental and discursive. It seeks to identify principles, strategies and tools that can be applied in a range of cultural settings. The paper includes a thematic analysis of the cultural contexts and policy environments of the participating countries in order to identify the obstacles to teacher leadership and to inform the nature of the support strategies employed

Effects of La substitution on superconducting state of CeCoIn5

We report effects of La substitution on superconducting state of heavy fermion superconductor CeCoIn5, as seen in transport and magnetization measurements. As opposed to the case of conventional superconductors, pair breaking by nonmagnetic La results in depression of Tc and indicates strong gap anisotropy. Upper critical field Hc2 values decrease with increased La concentration, but the critical field anisotropy, gamma=Hc2(a)/Hc2(c), does not change in the Ce_{1-x}La_xCoIn5 (x=0-0.15). The electronic system is in the clean limit for all values of x.Comment: Submitted to Phys. Rev.

Response of the Heavy-Fermion Superconductor CeCoIn5_5 to Pressure: Roles of Dimensionality and Proximity to a Quantum-Critical Point

We report measurements of the pressure-dependent superconducting transition temperature $T_c$ and electrical resistivity of the heavy-fermion compound CeCoIn$_5$. Pressure moves CeCoIn$_5$ away from its proximity to a quantum-critical point at atmospheric pressure. Experimental results are qualitatively consistent with theoretical predictions for strong-coupled, d-wave superconductivity in an anisotropic 3D superconductor.Comment: 9 pages, 5 figure