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Plant viral nanoparticles (VNPs) are attractive to nanomedicine researchers because of their safety, ease of production, resistance, and straightforward functionalization. In this paper, we developed and successfully purified a VNP derived from turnip mosaic virus (TuMV), a well-known plant pathogen, that exhibits a high affinity for immunoglobulins G (IgG) thanks to its functionalization with the Z domain of staphylococcal Protein A via gene fusion. We selected cetuximab as a model IgG to demonstrate the versatility of this novel TuMV VNP by developing a fluorescent nanoplatform to mark tumoral cells from the Cal33 line of a tongue squamous cell carcinoma. Using confocal microscopy, we observed that fluorescent VNP–cetuximab bound selectively to Cal33 and was internalized, revealing the potential of this nanotool in cancer research.

Filamentous plant virus-derived nanoparticles are biodegradable and noninfectious to humans. Their structure is also amenable to chemical modifications. They constitute an appealing material for biomedical applications including imaging and drug delivery. We had previously used turnip mosaic virus-derived nanoparticles (TuMV-NPs) to increase antibody-sensing in vivo, to prevent biofilm formation and to build biological nanoscaffolds. Materials & methods: We analyzed TuMV-NP biodistribution and tumor homing using in vivo imaging. We studied in vitro the interaction with human cancer cell lines and the antiproliferative effect of epigallocatechin gallate-functionalized TuMV-NPs. Results & conclusion: TuMV-NPs are efficiently internalized by human cells and show good tumor homing. The antiproliferative effect of epigallocatechin gallate-TuMV-NPs suggests that they could offer a potential anticancer therapy.

paper presents an improved approach for investigating submarine groundwater discharge (SGD) based on radon mapping and radon mass balancing in the coastal sea. While the use of radon as an environmental tracer in SGD studies is well-established, we identified based on our longstanding experience six methodical shortcomings of the conventional approach and suggest corresponding developments. The shortcomings include: (1 and 2) inadequate consideration of both detection equipment response delay and influence of tidal stage; (3 and 4) incorrect quantification of radon losses, due to offshore mixing and degassing resulting in a potentially incorrect radon mass balance; (5) inaccurate determination of the terrestrial groundwater endmember, due to inhomogeneous radon distribution in the coastal aquifer; and (6) difficulties in distinguishing between discharged fresh groundwater and recirculated seawater. The improved approach is practically demonstrated in a step by step manner in a large-scale field study, which was carried out in False Bay (South Africa) and which consisted of two parts, namely (i) qualitative SGD localization along the entire False Bay coastline based on coastal radon distribution patterns and (ii) quantitative SGD investigation within a defined coastal area of interest (AOI) based on a radon mass balance (RMB). The plausibility of the AOI related results was evaluated by a hydrogeological model, used for qualitative SGD localization, and a hydrological model, applied for estimating groundwater recharge within the AOI catchment.

The management of water and land resources in the Distrito Federal (DF), Western Central Brazil is characterized by very dynamic changes of land use/land cover driven by economic development, population growth and climate change. This problem is addressed by the project IWAS-ÁGUA DF which aims at creating a scientific base for the sustainable management of water and land resources in scope of an IWRM approach for the Distrito Federal. Land use change and climate change are affecting water resources in the Distrito Federal already substantially. Major effects identified during the project phase are (1) decreasing base flow during the dry season, partially caused by the expansion of agriculture and urbanization and (2) sediment generation and siltation of reservoirs mostly caused by urbanization. The general objective of the project is to contribute to an IWRM approach for the Distrito Federal, identifying causes of problems and possible solutions to maintain sustainable water supply for the region. The objective of the selected five case studies was to develop approaches with focus on all river basins of DF (1) to assess effects of land use on water resources in the past and with focus on the Pipiripau river basin (2) to predict the efficiency of measures (environmental services) and (3) to develop approaches for land use planning as part of an IWRM. For the Lago Paranoá basin two further case studies (4) for the identification of sediment sources and (5) to classify urban areas in terms of effects on water resources were carried out.

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The complex interactions between water resources, land-use change and water technologies are a major issue in many emerging countries of Southern America. Usable water resources are affected by natural conditions, such as, strong seasonal contrasts and high climatic variability, and rapid changes of land use and land cover that is caused by the dramatic expansion of agricultural land and urbanization processes.So far, the effects of the changing climate have had minor effects on water resources. Although regional data is rather scarce, global climate models predict substantial changes of climatic conditions in the future. A further pressure is that demand for water supply and waste water, both in terms of amount and spatial expansion, is increasing rapidly due to higher population densities caused by natural population growth and migration as well as higher per capita consumption.Integrated Water Resource Management in Brazil aims to present the results of the joint project IWAS-AGUA DF which deals with problems, causes and solutions in water supply in scope of integrated water resource management in western Central Brazil. The basic idea of the IWRM approach to be presented is to show how natural conditions and human interference are interacting and how technologies as well as concepts might help to manage such water resource systems in a sustainable way.

The development of effective sediment management strategies is a key requirement in tropical areas with fast urban development, like Brasilia DF, Brazil, because of the limited resources available. Accurate identification and management of sediment sources areas, however, is hampered by the dearth of reliable information on the primary sources of sediment. Few studies have attempted to quantify the source of sediment within fast urbanizing, mixed used, tropical catchments. In this study, statistically verified composite fingerprints and a multivariate mixing model have been used to identify the main land use specific sources of sediment deposited in the artificial Lago Paranoá, Central Brazil. Because of the variability of urban land use types within the Lago Paranoá sub-catchments, the fingerprinting approach was additionally undertaking for the Riacho Fundo sub-catchment. The main contributions from individual source types (i.e. surface materials from residential areas, constructions sites, road deposited sediment, cultivated areas, pasture, farm tracks, woodland and natural gullies) varied between the whole catchment and the Riacho Fundo sub-catchment, reflecting the different proportions of land uses. The sediments deposited in the silting zones of the Lago Paranoá originate largely from urban sources (85 ± 4%). Areas with (semi-) natural vegetation and natural gullies contribute 10 ± 2% of the sediment yield. Agricultural sites have only a minor sediment contribution of about 5 ± 4% within the whole catchment. Within the Riacho Fundo sub-catchment there is a significant contribution from urban (53 ± 4%) source, such as residential areas with semi-detached housings (42 ± 3%) with unpaved roads (12 ± 3%) and construction sites (20 ± 3%) and agricultural areas (31 ± 2%). The relative contribution from land use specific sou

One of the largest urban agglomerations in Brazil is the capital Brasilia and its surrounding area. Due to fast urban sprawl and accelerated land use changes, available water supplies are near their limits. The water supply depends largely on surface water collected in reservoirs. There are increasing concerns regarding water shortages due to sediment aggradations, and of water quality due to geochemical modification of sediments from human activities. The concentration of 18 chemical elements and five sediment properties was analyzed from different potential land-based sediment sources and deposited alluvial sediment within the Lago Paranoà catchment. The goal of this study was to assess the distribution of chemical elements and geochemical/physical properties of potential sediment sources in the Lago Paranoá catchment. Principal component analysis and hierarchical cluster analysis were used to investigate the influence of different land use types on the geochemistry of sediments. Geochemical fingerprints of anthropogenic activities were developed based on the results of the cluster analysis grouping. The anthropogenic input of land use specific geochemical elements was examined and quantified by the calculation of enrichment factors using the local geological background as reference. Through comparison of the geochemical signature of potential sediment sources and alluvial sediments of the Lago Paranoá and sub-catchments, the relative contribution of land use specific sediment sources to the sediment deposition of the main water reservoir were estimated. The existing findings suggest a strong relationship between land use and quantifiable features of sediment geochemistry and indicate that urban land use had the greatest responsibility for recent silting in the Lago Paranoá. This assessment helps to characterize the role of human activities in mixed-used watersheds on sediment properties, and provides essential information to guide management responses towards mor

The intense use of water for both public supply and agricultural production causes societal conflicts and environmental problems in the Brazilian Federal District. A serious consequence of this is nonpoint source pollution which leads to increasing water treatment costs. Hence, this study investigates in how far agricultural Best Management Practices (BMPs) might contribute to sustainable water resources management and soil protection in the region. The Soil and Water Assessment Tool (SWAT) was used to study the impact of those practices on streamflow and sediment load in the intensively cropped catchment of the Pipiripau River. The model was calibrated and validated against measured streamflow and turbidity-derived sediment loads. By means of scenario simulations, it was found that structural BMPs such as parallel terraces and small sediment basins (‘Barraginhas’) can lead to sediment load reductions of up to 40%. The implementation of these measures did not adversely affect the water yield. In contrast, multi-diverse crop rotations including irrigated dry season crops were found to be disadvantageous in terms of water availability by significantly reducing streamflow during low flow periods. The study considers rainfall uncertainty by using a precipitation data ensemble, but nevertheless highlights the importance of well established monitoring systems due to related shortcomings in model calibration. Despite the existing uncertainties, the model results are useful for water resource managers to develop water and soil protection strategies for the Pipiripau River Basin and for watersheds with similar characteristics.

Precipitation patterns in the tropics are characterized by extremely high spatial and temporal variability that are difficult to adequately represent with rain gauge networks. Since precipitation is commonly the most important input data in hydrological models, model performance and uncertainty will be negatively impacted in areas with sparse rain gauge networks. To investigate the influence of precipitation uncertainty on both model parameters and predictive uncertainty in a data sparse region, the integrated river basin model SWAT was calibrated against measured streamflow of the Pipiripau River in Central Brazil. Calibration was conducted using an ensemble of different precipitation data sources, including: (1) point data from the only available rain gauge within the watershed, (2) a smoothed version of the gauge data derived using a moving average, (3) spatially distributed data using Thiessen Polygons (which includes rain gauges from outside the watershed), and (4) Tropical Rainfall Measuring Mission radar data. For each precipitation input model, the best performing parameter set and their associated uncertainty ranges were determined using the Sequential Uncertainty Fitting Procedure. Although satisfactory streamflow simulations were generated with each precipitation input model, the results of our study indicate that parameter uncertainty varied significantly depending upon the method used for precipitation data-set generation. Additionally, improved deterministic streamflow predictions and more reliable probabilistic forecasts were generated using different ensemble-based methods, such as the arithmetic ensemble mean, and more advanced Bayesian Model Averaging schemes. This study shows that ensemble modeling with multiple precipitation inputs can considerably increase the level of confidence in simulation results, particularly in data-poor regions.

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This paper emphasizes the need of an improved consideration of the spatial distribution and functionality of forests in river basin management. The review of relevant papers has shown that forests, despite their frequent occurrence in temperate zones, play presently only a minor role in river basin management. In general, most of the studies highlight the positive effect of forests on water and nutrient fluxes in river basins. But hydrologists have also reported consistently flood events in or originating from forested areas. In context of the discussion on forest ecology and water quality it became obvious, that forest ecosystems can be sources depending on system properties, time and atmogenic pollution. The simulation of land use changes on water yield in forested river basins has been carried out in a great number of research projects, but mostly without considering the spatial distributed function of forests. The objective of our work is thus to improve the consideration of spatial distribution of forests in river basins and its effect on water yield and water quality. The most promising approaches in the future are either spatial explicit models or integrated models with both improved forest modules and landscape positioning. The efficiency of these models could be proved by using virtual catchments. As a first conceptual approach towards the base concept of a virtual catchment, we propose a five-units-model (FUM), representing cross-sections with typical land use sequences. The basic idea of our model is to identify major process units and to implement them in the river basin modeling and management.