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The present study was conducted on the main landfill of the city of Zagreb which contains about 5 million tons of waste disposed of directly onto highly permeable alluvial sediments. The investigations wereaimed at assessing the impact of contamination from the landfill on underlying soil and comprised the determination of a broad spectrum of inorganic and organic constituents in the samples (size fractions <2 mm) of solid waste, soil and aquifer sediments. Both the total content of various contaminants as well as their part which is readily leachable with water were determined in the examined samples. Compound classes identified in the landfill can be classified into the two main categories: (1) markers of biological waste and of its microbial transformation (ammonia, dissolved organic carbon, short-chain aliphatic acids, phenols. derivatives of abietic acid) and (2) markers of anthropogenic waste (toxic metals, hydrocarbons, chlorinated hydrocarbons, surfactant-derived compounds, phthalates, pharmaceutical chemicals). The complex assemblages of contaminants were shown to change dramatically during the transport from the solid waste through unsaturatedzone of the soil to aquifer sediments. It was shown that, in addition to the vertical infiltration of leachate from the solid waste, the hydrological regime of groundwater has also a strong impact on the contaminant distribution in soils below the landfill. (c) 1998 IAWQ. Published by Elsevier Science Ltd. [ABSTRACT FROM AUTHOR]

The environmental impact of the main landfill of the city of Zagreb (Croatia), which contains about 5 million tons of waste, on the adjacent groundwater was studied. The waste is disposed of directly onto the highly permeable alluvial sediments, only few kilometres upstream of a large protected groundwater zone. Systematic monitoring was performed in the framework of a major project aimed to assess strategies for remediation of the landfill. Results obtained in 6 sampling campaigns during 1995--96 were used to determine the redox zones in the leachate plume and to describe horizontal and vertical distributions ofselected contaminants. A relatively narrow non-continuous iron-reducing zone was found along the edge of the landfill in the prevailing directions of the groundwater flow. Even after a distance of 1200 m the redox conditions in the aquifer still remained anaerobic (nitrate-reducing), while a permanently aerobic zone was present only upstream from the landfill. The horizontal distribution of the contaminants was highly dependant on the hydrological regime, but the preferential direction of spreading was toward the protected groundwater zone. Moreover, it was shown that this aquifer section is polluted not only in the surface layer but across its whole vertical profile (as deep as 60 m). (c) 1998 IAWQ. Published by Elsevier Science Ltd. [ABSTRACT FROM AUTHOR]

The feasibility of using β-cyclodextrin (βCD) as an eco-friendly carrier of boric acid for the protection of strand-based wood composites against decay fungi was evaluated. The formation of a βCD-boric acid (βCD-B) complex was confirmed by the appearance of the boron-oxygen bond by using attenuated total reflection-Fourier transform infrared spectroscopy. Chemical shifts of around 6.25 and 1.41 ppm were also observed in 1 H Nuclear Magnetic Resonance (NMR) and 11 B NMR spectra, respectively. The βCD-B preservatives at two levels (5 and 10 wt.%) were uniformly blended with southern pine strands that were subsequently sprayed with polymeric methylene diphenyl diisocyanate (pMDI) resin. The blended strands were formed into a loose mat by hand and consolidated into 25 × 254 × 12 mm oriented strand boards (OSB) using a hot-press. The OSB panels were cut to end-matched internal bonding (IB) strength and fungal decay resistance test specimens. The vertical density profiles (VDPs) of the IB specimens were measured using an X-ray based density profiler and the specimens with statistically similar VDPs were selected for the IB and decay tests. The IB strength of the treated specimens was lower than the control specimens but they were above the required IB strength of heavy-duty load-bearing boards for use in humid conditions, specified in the BS EN 300:2006 standard. The reduced IB of preservative-treated OSB boards could be explained by the destabilized resin upon the addition of the βCD-B complex, as indicated by the differential scanning calorimetry (DSC) results. The resistance of the OSB panels against two brown-rot fungi (i.e., G. trabeum or P. placenta ) was evaluated before and after accelerated leaching cycles. The treated OSBs exposed to the fungi showed an average mass loss of lower than 3% before leaching, while the untreated OSBs had 49 and 35% mass losses due to decay by G. trabeum or P. placenta , respectively. However, upon the leaching, the treatment provided protection only against G. trabeum to a certain degree (average mass loss of 15%). The experimental results suggest that protection efficacy against decay fungi after leaching, as well as the adhesion of the OSB strands, can be improved by increasing the amount of pMDI resin.

During an immune response, activated antigen (Ag)-specific T cells condition dendritic cells (DCs) to enhance DC function and survival within the inflamed draining lymph node (LN). It has been difficult to ascertain the role of the tumor necrosis factor (TNF) superfamily member lymphotoxin-alphabeta (LTalphabeta) in this process because signaling through the LTbeta-receptor (LTbetaR) controls multiple aspects of lymphoid tissue organization. To resolve this, we have used an in vivo system where the expression of TNF family ligands is manipulated only on the Ag-specific T cells that interact with and condition Ag-bearing DCs. We report that LTalphabeta is a critical participant required for optimal DC function, independent of its described role in maintaining lymphoid tissue organization. In the absence of LTalphabeta or CD40L on Ag-specific T cells, DC dysfunction could be rescued in vivo via CD40 or LTbetaR stimulation, respectively, suggesting that these two pathways cooperate for optimal DC conditioning.