bluuebunny/crossref_metadata_2025 huggingface dataset:
Do trophic cascades affect the storage and flux of atmospheric carbon? An analysis of sea otters and kelp forests
Authors: Wilmers Christopher C , Estes James A , Edwards Matthew , Laidre Kristin L , Konar Brenda
Published: November 2012

We combine data collected from the past 40 years to estimate the indirect effects of sea otters (Enhydra lutris) on ecosystem carbon (C) production and storage across their North American range, from Vancouver Island to the western edge of Alaska's Aleutian Islands. We find that sea otters, by suppressing sea urchin (Strongylocentrotus spp) populations, allow kelp (Order Laminariales) ecosystems to develop with a net primary productivity (NPP) of 313–900 grams C per square meter per year (g C m−2 yr−1) and biomass density of 101–180 grams C per square meter (g C m−2). In the absence of sea otters, these areas would have an NPP of 25–70 g C m−2 yr−1 and biomass density of 8–14 g C m−2. Over an ecosystem area of approximately 5.1 × 1010 m2, the effect of sea otter predation on living kelp biomass alone represents a 4.4‐to 8.7‐teragram increase in C storage. At 2012 prices (US$47 per ton of C), this stored C would be valued at US$205 million–$408 million on the European Carbon Exchange. Although questions remain concerning the pathways and compartments of kelp C flux and storage, sea otters undoubtedly have a strong influence on these elements of the C cycle. Predator‐induced trophic cascades likely influence the rates of C flux and storage in many other species and ecosystems.
Lessons from lady beetles: accuracy of monitoring data from US and UK citizen‐science programs
Authors: Gardiner Mary M , Allee Leslie L , Brown Peter MJ , Losey John E , Roy Helen E , Smyth Rebecca Rice
Published: November 2012

Citizen scientists have the potential to play a crucial role in the study of rapidly changing lady beetle (Coccinellidae) populations. We used data derived from three coccinellid‐focused citizen‐science programs to examine the costs and benefits of data collection from direct citizen‐science (data used without verification) and verified citizen‐science (observations verified by trained experts) programs. Data collated through direct citizen science overestimated species richness and diversity values in comparison to verified data, thereby influencing interpretation. The use of citizen scientists to collect data also influenced research costs; our analysis shows that verified citizen science was more cost effective than traditional science (in terms of data gathered per dollar). The ability to collect a greater number of samples through direct citizen science may compensate for reduced accuracy, depending on the type of data collected and the type(s) and extent of errors committed by volunteers.
The current state of citizen science as a tool for ecological research and public engagement
Authors: Dickinson Janis L , Shirk Jennifer , Bonter David , Bonney Rick , Crain Rhiannon L , Martin Jason , Phillips Tina , Purcell Karen
Published: November 2012

Approaches to citizen science – an indispensable means of combining ecological research with environmental education and natural history observation – range from community‐based monitoring to the use of the internet to “crowd‐source” various scientific tasks, from data collection to discovery. With new tools and mechanisms for engaging learners, citizen science pushes the envelope of what ecologists can achieve, both in expanding the potential for spatial ecology research and in supplementing existing, but localized, research programs. The primary impacts of citizen science are seen in biological studies of global climate change, including analyses of phenology, landscape ecology, and macro‐ecology, as well as in sub‐disciplines focused on species (rare and invasive), disease, populations, communities, and ecosystems. Citizen science and the resulting ecological data can be viewed as a public good that is generated through increasingly collaborative tools and resources, while supporting public participation in science and Earth stewardship.
Citizen science on a local scale: the Plants of Concern program
Authors: Havens Kayri , Vitt Pati , Masi Susanne
Published: November 2012

Plants of Concern, a program administered by the Chicago Botanic Garden, relies on citizen scientists to monitor rare plant populations in the greater Chicago, Illinois, region. Over 650 volunteers monitor 990 populations of 233 endangered, threatened, and rare plant species. Volunteers attend a day‐long workshop to learn a variety of monitoring techniques and also receive one‐on‐one mentoring in the field to help them apply the appropriate methodology for the species and sites they choose to monitor.
Data validation in citizen science: a case study from Project FeederWatch
Authors: Bonter David N , Cooper Caren B
Published: November 2012

To become more widely accepted as a valuable research tool, citizen‐science projects must find ways to ensure that data gathered by large numbers of people with varying levels of expertise are of consistently high quality. Here, we describe a data validation protocol developed for Project FeederWatch, a continent‐wide bird monitoring program, that is designed to increase researchers' and participants' confidence in the data being collected.
Insects and plants: engaging undergraduates in authentic research through citizen science
Authors: Oberhauser Karen , LeBuhn Gretchen
Published: November 2012

Many citizen‐science programs – including the Monarch Larva Monitoring Project and the Great Sunflower Project – are managed by university researchers, and this connection has facilitated the involvement of undergraduate students in project design, data collection and management, and independent research. Here, we describe the benefits of undergraduate involvement, and encourage citizen‐science coordinators and college faculty to increase the use of citizen science and citizen‐science data in undergraduate training.
National Geographic FieldScope: a platform for community geography
Authors: Switzer Anna , Schwille Kathleen , Russell Eric , Edelson Daniel
Published: November 2012

National Geographic FieldScope is designed to allow citizen scientists to visualize and analyze their data via online GIS maps. It is being developed with and for citizen‐science organizations and will facilitate collaborative problem solving and decision making.
The future of citizen science: emerging technologies and shifting paradigms
Authors: Newman Greg , Wiggins Andrea , Crall Alycia , Graham Eric , Newman Sarah , Crowston Kevin
Published: November 2012

Citizen science creates a nexus between science and education that, when coupled with emerging technologies, expands the frontiers of ecological research and public engagement. Using representative technologies and other examples, we examine the future of citizen science in terms of its research processes, program and participant cultures, and scientific communities. Future citizen‐science projects will likely be influenced by sociocultural issues related to new technologies and will continue to face practical programmatic challenges. We foresee networked, open science and the use of online computer/video gaming as important tools to engage non‐traditional audiences, and offer recommendations to help prepare project managers for impending challenges. A more formalized citizen‐science enterprise, complete with networked organizations, associations, journals, and cyberinfrastructure, will advance scientific research, including ecology, and further public education.
Deep cold‐water corals as nurseries for fish larvae
Authors: Baillon Sandrine , Hamel Jean-François , Wareham Vonda E , Mercier Annie
Published: November 2012

As a consequence of the decline of numerous commercial fish populations, an ecosystem‐based approach to fisheries management, which includes the protection of essential fish habitat (EFH), has emerged. Cold‐water coral (CWC) sites are recognized as biodiversity hotspots, but numerous examples of CWC destruction and degradation as a result of anthropogenic activities are well documented. However, although functional connections between CWCs and fish stocks are suspected, based on correlative evidence, proof of any close or direct relationship identifying CWCs as EFH is still lacking. Here, we provide evidence of the utilization of CWCs by fish larvae, mainly those of redfish (Sebastes spp). In multiyear surveys, fish larvae were consistently found closely associated with five species of sea pen (Octocorallia: Pennatulacea) in April and May. Prevalence and/or yields of fish larvae varied with coral host species, depth, location, and colony size. Evidence of the role of CWCs in the early life history of some fish species provides the strongest argument yet for the categorization of CWCs as EFH in the design of management programs.
Magnetotelluric study of the Remiremont-Epinal-Rambervillers zone of migrating seismicity, Vosges (France)
Authors: Bourlange Sylvain , Mekkawi Mahmoud , Conin Marianne , Schnegg Pierre-André
Published: November 2012

The magnetotelluric method has been used to image the deep electrical structure of the Remiremont-Epinal-Rambervillers region in the French Vosges Massif, which has presented a significant seismic activity in the past decades. Several earthquakes of moderate magnitude (up to 5.1) occurred in this area with a systematic migration along a nearly N-S direction. Inversion of the magnetotelluric data reveals zones of high electrical conductivity. A large conductive body presents a significative spatial correlation with the region that was most recently affected by earthquakes. This conductive body is interpreted as a consequence of the presence of a fluid filled basement fault network in proximity to the zone affected by the last seismic crisis, where fluid pressure diffusion takes place for several years after the main shock and participates in maintaining a microseismic activity.
Incised valleys and tidal seaways: the example of the Miocene Uzès-Castillon basin, SE France
Authors: Reynaud Jean-Yves , Vennin Emmanuelle , Parize Olivier , Rubino Jean-Loup , Bourdillon Chantal
Published: November 2012

The sedimentology and stratigraphy of the Miocene deposits of the Uzès-Castillon basin are revisited. This basin, located in SE France at the junction between the perialpine foreland basin and the W Mediterranean margin, sits in a syncline that formed during the latest Cretaceous Pyrenean tectonic phase. It records the succession of shallow-water mixed siliciclastic to dominantly bioclastic carbonates that alternate with shelf marls. The clastic carbonates were accumulated as a stack of subtidal dunes and bars that were formed by tidal currents channelized in a seaway following the syncline axis. The marls indicate deposition in more protected and locally deeper waters, as interfluves of the sea-way were drowned. Borehole data suggest that the marls are encased over tens of meters in the underlying bioclastic deposits, thus pointing to incised-valley fills. Contrarily to what is observed in the main Rhodanian basin, the molassic deposits are not restricted to transgressive systems tracts but may also correspond to forced regressive systems tracts. Four depositional sequences are identified, ranging from the Lower Burdigalian to the Langhian. They constitute a transgressive-regressive sequence set which might express the uplift of the area starting in the Late Burdigalian. This is consistent with the incision of the Middle Miocene deposits into the Lower Miocene ones as observed in other places of the main Rhodanian basin.
Pilot-scale demonstration of the hybrid zero-valent iron process for treating flue-gas-desulfurization wastewater: Part I
Authors: Huang Yong H. , Peddi Phani K. , Zeng Hui , Tang Ci-Lai , Teng Xinjun
Published: November 2012

The hybrid zero-valent-iron (hZVI) process is a novel chemical treatment process that has shown great potential in previous laboratory and field bench-top scale tests for removing selenium, mercury and nutrients from various industrial wastewaters. In this study, a pilot-scale demonstration was conducted to continuously treat 3.8–7.6 L/min (1–2 gpm) of the flue-gas-desulfurization (FGD) wastewater at a coal-fired power plant for five months. Results show that the hZVI process could simultaneously reduce selenate-Se from 1 to 3 mg/L to below 10 μg/L and mercury from over 100 μg/L to below 10 ng/L in compliance with the new stringent effluent discharge limits planned by the U.S. EPA for Se and Hg. A three-stage hZVI system with a combined hydraulic retention time of 12 h is sufficient for Se treatment, while a single-stage system can meet Hg treatment requirement. The successful pilot study demonstrated that the hZVI process is scalable and could be a reliable, low-cost, high-performance treatment platform with many application potentials, particularly, for solving some of the toughest heavy metal water problems.
Application of response surface method to carbamazepine removal in photo-ozonation reaction under alkaline condition
Authors: Im J. K. , Zoh K. D.
Published: November 2012

In this study, the photo-ozonation reaction for carbamazepine (CBZ) removal was investigated under alkaline conditions. Response surface methodology based on a central composite design was used to obtain the optimum experimental conditions, and examine both main and interaction effects of the photo-ozonation reaction variables such as O3 concentration, H2O2 concentration and UV intensity. The level of O3 concentration significantly influenced CBZ removal (p < 0.001). CBZ removal increased with increasing both O3 and H2O2 concentration up to a certain level, whereas further increase in O3 and H2O2 concentration resulted in an adverse effect due to the hydroxyl radical scavenging effect. The optimum conditions for complete CBZ removal at pH 9 were found to be 0.89 mg of O3 l−1, 4.85 mg of H2O2 l−1 and 3.18 mW of UV intensity cm−2, respectively.
Single-solute and bisolute sorption of phenol and trichloroethylene from aqueous solution onto modified montmorillonite and application of sorption models
Authors: Wu C. D. , Wang L. , Hu C. X. , He M. H.
Published: November 2012

The single-solute and bisolute sorption behaviour of phenol and trichloroethylene, two organic compounds with different structures, onto cetyltrimethylammonium bromide (CTAB)-montmorillonite was studied. The monolayer Langmuir model (MLM) and empirical Freundlich model (EFM) were applied to the single-solute sorption of phenol or trichloroethylene from water onto monolayer or multilayer CTAB-montmorillonite. The parameters contained in the MLM and EFM were determined for each solute by fitting to the single-solute isotherm data, and subsequently utilized in binary sorption. The extended Langmuir model (ELM) coupled with the single-solute MLM and the ideal adsorbed solution theory (IAST) coupled with the single-solute EFM were used to predict the binary sorption of phenol and trichloroethylene onto CTAB-montmorillonite. It was found that the EFM was better than the MLM at describing single-solute sorption from water onto CTAB-montmorillonite, and the IAST was better than the ELM at describing the binary sorption from water onto CTAB-montmorillonite.
Car wash wastewater treatment and water reuse – a case study
Authors: Zaneti R. N. , Etchepare R. , Rubio J.
Published: November 2012

Recent features of a car wash wastewater reclamation system and results from a full-scale car wash wastewater treatment and recycling process are reported. This upcoming technology comprises a new flocculation–column flotation process, sand filtration, and a final chlorination. A water usage and savings audit (22 weeks) showed that almost 70% reclamation was possible, and fewer than 40 L of fresh water per wash were needed. Wastewater and reclaimed water were characterized by monitoring chemical, physicochemical and biological parameters. Results were discussed in terms of aesthetic quality (water clarification and odour), health (pathological) and chemical (corrosion and scaling) risks. A microbiological risk model was applied and the Escherichia coli proposed criterion for car wash reclaimed water is 200 CFU 100 mL−1. It is believed that the discussions on car wash wastewater reclamation criteria may assist institutions to create laws in Brazil and elsewhere.
Effect of co-existing copper and calcium on the removal of As(V) by reused aluminum oxides
Authors: Yang J. K. , Park Y. J. , Kim K. H. , Lee H. Y. , Min K. C. , Lee S. M.
Published: November 2012

Among the various heavy metals, arsenic is frequently found in abandoned mine drainage and the environmental fate of arsenic in real aqueous solutions can be highly dependent on the presence of co-existing ions. In this study, removal of arsenate through adsorption on the reused aluminum oxide or through precipitation was investigated in a single and in a binary system as a function of pH and concentration. Different removal behaviors of arsenate were observed in the presence of different cations as well as a variation of the molar ratios of arsenate to cations. Co-operative effects on arsenate removal by precipitation in solution occurred with an increase of copper concentration, while a decrease of arsenate removal resulted in increasing calcium concentration. It was observed that the arsenate removal in the presence of calcium would be highly dependent on the molar ratios of both elements.
Mathematical modeling of upflow anaerobic sludge blanket (UASB) reactor treating domestic wastewater
Authors: Elmitwalli Tarek
Published: November 2012

Although the upflow anaerobic sludge blanket (UASB) reactor has been widely applied for domestic wastewater treatment in many developing countries, there is no sufficient mathematical model for proper design and operation of the reactor. An empirical model based on non-linear regression was developed to represent the physical and chemical removal of suspended solids (SS) in the reactor. Moreover, a simplified dynamic model based on ADM1 and the empirical model for SS removal was developed for anaerobic digestion of the entrapped SS and dissolved matter in the wastewater. The empirical model showed that effluent suspended chemical oxygen demand (CODss) concentration is directly proportional to the influent CODss concentration and inversely proportional to both the hydraulic retention time (HRT) of the reactor and wastewater temperature. For obtaining sufficient CODss removal, the HRT of the UASB reactor must be higher than 4 h, and higher HRT than 12 h slightly improved CODss removal. The dynamic model results showed that the required time for filling the reactor with sludge mainly depends on influent total chemical oxygen demand (CODt) concentration and HRT. The influent CODt concentration, HRT and temperature play a crucial role on the performance of the reactor. The results indicated that shorter HRT is needed for optimization of CODt removal, as compared with optimization of CODt conversion to methane. Based on the model results, the design HRT of the UASB reactor should be selected based on the optimization of wastewater conversion and minimization of biodegradable SS accumulation in the sludge bed, not only based on COD removal, to guarantee a stable reactor performance.
Design and assessment of urban drainage and water reuse systems for the reconstruction of formerly industrial areas: a case in Beijing
Authors: Liu L. , Zeng S. , Dong X. , Chen J.
Published: November 2012

The Shougang Group is an industrial steel enterprise occupying 800 ha in Beijing that will cease production by 2010. The area will be converted to a new financial and commercial zone. The rebuilding of the water infrastructure in this area should address water shortages in Beijing and retain the industrial landmark of a large cooling water tank. A design framework and an assessment system with 11 indicators were developed for this purpose. Four reconstruction schemes are presented here. Scheme 1 is a traditional system that completely depends on outside the municipal facility. Schemes 2, 3, and 4 are systems to separately discharge greywater and blackwater. Scheme 4 uses a vacuum system that allows the reclamation of nutrients. Schemes 2 and 4 use wetland-treated greywater to fill the water tank. Scheme 3 reuses greywater for toilets after on-site treatment. Scheme 2 is recommended due to its lower cost, greater environmental benefit, moderate resource reclamation, and higher technical feasibility.
Trends and variability of climate and river flow in the region of Costa das Baleias, Brazil
Authors: Genz F. , Tanajura C. A. S.
Published: November 2012

There is an ongoing effort by the scientific community to regionalize climate studies to support local development plans. The area of interest is the Costa das Baleias on the east coast of northeast Brazil. It is located in a transition region of precipitation trends, and so assessing the local signal and magnitude is necessary. A series of annual anomalies of surface air temperature, precipitation and river discharge were analyzed from 1946 to 2010. The modified Mann–Kendall test was applied to detect trends. Temperature anomalies showed a consistent positive trend since 1950. Precipitation anomalies tended to decrease, though not significantly. River discharge rates showed a consistent positive trend. However, from the 1980s onwards, both the precipitation and the river discharge anomalies had the same decreasing tendency. The precipitation and discharge behavior are likely due to the combined effect of human interventions in the river basins including local, synoptic and global climate effects. The inter-annual variability was characterized by spectral analysis. Cycles were identified for the precipitation and the river discharge with periods of 2–3 years, 3–4 years, 7–8 years and 11–12 years. The decadal frequency is consistent with the South Atlantic and El Niño indices. This work strongly indicates that climate is changing in Costa das Baleias and further work is needed to investigate the mechanisms that link local to large-scale variability.
Identifying energy and carbon footprint optimization potentials of a sludge treatment line with Life Cycle Assessment
Authors: Remy C. , Lesjean B. , Waschnewski J.
Published: November 2012

This study exemplifies the use of Life Cycle Assessment (LCA) as a tool to quantify the environmental impacts of processes for wastewater treatment. In a case study, the sludge treatment line of a large wastewater treatment plant (WWTP) is analysed in terms of cumulative energy demand and the emission of greenhouse gases (carbon footprint). Sludge treatment consists of anaerobic digestion, dewatering, drying, and disposal of stabilized sludge in mono- or co-incineration in power plants or cement kilns. All relevant forms of energy demand (electricity, heat, chemicals, fossil fuels, transport) and greenhouse gas emissions (fossil CO2, CH4, N2O) are accounted in the assessment, including the treatment of return liquor from dewatering in the WWTP. Results show that the existing process is positive in energy balance (–162 MJ/PECOD * a) and carbon footprint (–11.6 kg CO2-eq/PECOD * a) by supplying secondary products such as electricity from biogas production or mono-incineration and substituting fossil fuels in co-incineration. However, disposal routes for stabilized sludge differ considerably in their energy and greenhouse gas profiles. In total, LCA proves to be a suitable tool to support future investment decisions with information of environmental relevance on the impact of wastewater treatment, but also urban water systems in general.
The management of urban surface water flood risks: SUDS performance in flood reduction from extreme events
Authors: Viavattene C. , Ellis J. B.
Published: November 2012

The need to improve the urban drainage network to meet recent urban growth and the redevelopment of old industrial and commercial areas provides an opportunity for managing urban surface water infrastructure in a more sustainable way. The use of sustainable urban drainage systems (SUDS) can reduce urban surface water flooding as well as the pollution impact of urban discharges on receiving waters. However, these techniques are not yet well known by many stakeholders involved in the decision-making process, or at least the evidence of their performance effectiveness may be doubted compared with more traditional engineering solutions often promoted by existing 1D/2D drainage models. The use of geographic information systems (GIS) in facilitating the inter-related risk analysis of sewer surface water overflows and urban flooding as well as in better communication with stakeholders is demonstrated in this paper. An innovative coupled 1D/2D urban sewer/overland flow model has been developed and tested in conjunction with a SUDS selection and location tool (SUDSLOC) to enable a robust management approach to surface water flood risks and to improve the resilience of the urban drainage infrastructure. The paper demonstrates the numerical and modelling basis of the integrated 1D/2D and SUDSLOC approach and the working assumptions and flexibility of the application together with some limitations and uncertainties. The role of the SUDSLOC modelling component in quantifying flow, and surcharge reduction benefits arising from the strategic selection and location of differing SUDS controls are also demonstrated for an extreme storm event scenario.
Realising sustainable urban water management: Can social theory help?
Authors: Bos J. J. , Brown R. R.
Published: November 2012

It has been acknowledged, in Australia and beyond, that existing urban water systems and management lead to unsustainable outcomes. Therefore, our current socio-technical systems, consisting of institutions, structures and rules, which guide traditional urban water practices, need to change. If a change towards sustainable urban water management (SUWM) practices is to occur, a transformation of our established social-technical configuration that shapes the behaviour and decision making of actors is needed. While some constructive innovations that support this transformation have occurred, most innovations remain of a technical nature. These innovative projects do not manage to achieve the widespread social and institutional change needed for further diffusion and uptake of SUWM practices. Social theory, and its research, is increasingly being recognised as important in responding to the challenges associated with evolving to a more sustainable form of urban water management. This paper integrates three areas of social theories around change in order to provide a conceptual framework that can assist with socio-technical system change. This framework can be utilised by urban water practitioners in the design of interventions to stimulate transitions towards SUWM.
Antibiotic resistance among autochthonous aquatic environmental bacteria
Authors: Schreiber Christiane , Kistemann Thomas
Published: November 2012

Antibiotics are widely used in both human and veterinary medicine and antibiotic-resistant bacteria cause problems in antibiotic therapy. The current study was conducted in the catchment area of the river Swist (Germany) and focuses on the resistance of environmental Rhodospirillaceae to antibiotics used in human medicine. The samples collected reflect different levels of human impact on the environment. In total, 614 isolates were tested for antibiotic susceptibility. About half of these isolates were susceptible to all substances tested. Oxacillin resistance was observed most frequently (41%). Resistant Rhodospirillaceae were detected in wastewater effluent from a municipal sewage treatment plant, as well as in non-polluted upper reaches. The highest multi-resistance level was detected in small tributaries and it surprisingly decreased with an increasing influence of municipal wastewater. It could be shown that the detected resistances were acquired rather than intrinsic. Besides natural occurrence of multi-resistance among non-sulphur purple bacteria, horizontal gene transfer and acquired cross-resistance against veterinary antibiotics are assumed to be important factors. To the authors’ knowledge, this is the first study investigating the potential of Rhodospirillaceae as a reservoir for resistance to antibiotics used in human medicine. The consequence for resistance prevalence in human pathogens and for their antibiotic therapy needs evaluation.
Response of rock-fissure seepage to snowmelt in Mount Taihang slope-catchment, North China
Authors: Cao Jiansheng , Liu Changming , Zhang Wanjun
Published: November 2012

The complex physiographic and hydrogeological systems of mountain terrains facilitate intense rock-fissure seepages and multi-functional ecological interactions. As mountain eco-hydrological terrains are the common water sources of river basins across the globe, it is critical to build sufficient understanding into the hydrological processes in this unique ecosystem. This study analyzes infiltration and soil/rock-fissure seepage processes from a 65 mm snowfall/melt in November 2009 in the typical granitic gneiss slope catchment in the Taihang Mountains. The snowfall, snowmelt and melt-water processes are monitored using soil-water time-domain reflectometry (TDR) probes and tipping bucket flowmeters. The results suggest that snowmelt infiltration significantly influences soil/rock water seepage in the 0–100 cm soil depth of the slope-catchment. It is not only air temperature that influences snowmelt, but also snowmelt infiltration and rock-fissure seepage. Diurnal variations in rock-fissure seepage are in close correlation with air temperature (R2 > 0.7). Temperature also varies with soil/rock water viscosity, which element in turn influences soil/rock water flow. Invariably, water dynamics in the study area is not only a critical water supply element for domestic, industrial and agricultural uses, but also for food security and social stability.
Use of biogas for cogeneration of heat and electricity for local application: performance evaluation of an engine power generator and a sludge thermal dryer
Authors: Lobato L. C. S. , Chernicharo C. A. L. , Pujatti F. J. P. , Martins O. M. , Melo G. C. B. , Recio A. A. R.
Published: November 2012

A small unit of cogeneration of energy and heat was tested at the Centre for Research and Training on Sanitation UFMG/COPASA – CePTS, located at the Arrudas Sewage Treatment Plant, in Belo Horizonte, Minas Gerais, Brazil. The unit consisted of an engine power generator adapted to run on biogas, a thermal dryer prototype and other peripherals (compressor, biogas storage tank, air blower, etc.). The heat from engine power generator exhaust gases was directed towards the thermal dryer prototype to dry the sludge and disinfect it. The results showed that the experimental apparatus is self-sufficient in electricity, even producing a surplus, available for other uses. The tests of drying and disinfection of sludge lasted 7 h, leading to an increase in solids content from 4 to 8% (50% reduction in sludge volume). Although the drying of sludge was not possible (only thickening was achieved), the disinfection process proved very effective, enabling the complete inactivation of helminth eggs.
Anaerobic co-digestion of sewage sludge and primary clarifier skimmings for increased biogas production
Authors: Alanya S. , Yilmazel Y. D. , Park C. , Willis J. L. , Keaney J. , Kohl P. M. , Hunt J. A. , Duran M.
Published: November 2012

The objective of the study was to identify the impact of co-digesting clarifier skimmings on the overall methane generation from the treatment plant and additional energy value of the increased methane production. Biogas production from co-digesting clarifier skimmings and sewage sludge in pilot-scale fed-batch mesophilic anaerobic digesters has been evaluated. The digester was fed with increasing quantities of clarifier skimmings loads: 1.5, 2.6, 3.5 and 7.0 g COD equivalent/(L·d) (COD: chemical oxygen demand). Average volatile solids reduction of 65% was achieved in the scum-fed digester, compared with 51% in the control digester. Average 69% COD removal was achieved at highest scum loading (7 g COD eq/(L·d)) with approximate methane yield of 250 L CH4/kg COD fed (4 ft3/lb COD fed). The results show that scum as co-substrate in anaerobic digestion systems improves biogas yields while a 29% increase in specific CH4 yield could be achieved when scum load is 7 g COD eq/(L·d). Based on the pilot-scale study results and full-scale data from South East Water Pollution Control Plant and Northeast Water Pollution Control Plant the expected annual energy recovery would be approximately 1.7 billion BTUs or nearly 0.5 million kWh.
Impact of some herbicides on the biomass activity in biological treatment plants and biodegradability enhancement by a photo-Fenton process
Authors: Benzaquén T. B. , Benzzo M. T. , Isla M. A. , Alfano O. M.
Published: November 2012

In recent years, the use of agrochemicals has increased because they are essential for profitable agricultural production. Herbicides are heavily demanded compounds and among these, the most marketed are 2,4-D, atrazine and acetochlor. They have characteristics that can cause problems to humans and the environment. Therefore, it is necessary to design systems that can reduce these compounds to harmless molecules. This work aims at evaluating the possibility of incorporating these herbicides into degradable effluents in a biological treatment system, without reducing its efficiency. For this purpose, studies of organic matter degradability in the presence of these agrochemicals were performed. A synthetic effluent based on glucose and mineral salts was inoculated with microorganisms. Glucose consumption and biomass concentration were assessed. Subsequently, preliminary studies were performed to test the viability of degradation of the most harmful compound with an advanced oxidation process (AOP). The results showed that the incorporation of these herbicides into degradable effluents in a biological treatment system has a negative impact on microorganisms. Therefore, the application of an AOP, such as the Fenton or photo-Fenton processes, prior to a biological treatment was found to degrade these substances to simpler and less toxic molecules.
Remote sensing of suspended solids concentration in a reservoir with frequent wildland fires on its watershed
Authors: Bonansea M. , Fernandez R. L.
Published: November 2012

Wildland fire is an important disturbance factor that can cause severe ecological and watershed damage. Depending on fire severity and watershed extension, reservoir suspended solids concentration (SSC), which arrives through river load, is expected to increase. Satellite remote sensing is an alternative technique to measure SSC in a reservoir. In this paper we evaluate the applicability of multitemporal Landsat data for mapping and monitoring of the SSC in a reservoir whose watershed was exposed to fires. Besides, we aim to identify catchment areas that have been burned, estimating the level of burn severity that occurred because of the fire. The Landsat images were radiometrically, atmospherically and geometrically corrected. Using the differenced normalized burn ratio (dNBR) algorithm, the perimeter and severity of fire was mapped. A theoretical model to characterize the distribution of SSC using multitemporal Landsat data was developed. The relationship between burn severity maps, rainfall and SSC maps improved our understanding of management actions on a reservoir which suffers frequent wildfires on its watershed. The theoretical model here developed may be considered as a low cost measurement tool for water management authorities, particularly when in-situ data are not available.
Modelling micro-pollutant fate in wastewater collection and treatment systems: status and challenges
Authors: Plósz B. G. , Benedetti L. , Daigger G. T. , Langford K. H. , Larsen H. F. , Monteith H. , Ort C. , Seth R. , Steyer J.-P. , Vanrolleghem P. A.
Published: November 2012

This paper provides a comprehensive summary on modelling of micro-pollutants' (MPs) fate and transport in wastewater. It indicates the motivations of MP modelling and summarises and illustrates the current status. Finally, some recommendations are provided to improve and diffuse the use of such models. In brief, we conclude that, in order to predict the contaminant removal in centralised treatment works, considering the dramatic improvement in monitoring and detecting MPs in wastewater, more mechanistic approaches should be used to complement conventional, heuristic and other fate models. This is crucial, as regional risk assessments and model-based evaluations of pollution discharge from urban areas can potentially be used by decision makers to evaluate effluent quality regulation, and assess upgrading requirements, in the future.
The Mast Cell Pathway to Inflammation and Homeostasis: Pharmacolo- gical Insights
Authors: Kakavas S. , Zampeli E. , Papamichael K. , Delitheos B. , Tiligada E.
Published: November 2012

Mast cells (MCs) were first described by Paul Ehrlich as well fed granular cells that stain metachromatically. Today MCs are regarded as multifunctional, granulated, tissue-dwelling cells distributed in the perivascular spaces and connective tissues of every major organ of the body. Their long recognized phenotypic diversity might be associated not only with their anatomic distribution and mediator repertoire, but also with their functional characteristics related to the regulation of effector pathways. In addition to their historical involvement in type I hypersensitivity response, MCs have emerged as versatile effector cells with functional diversity and homeostatic functions in non-IgE-mediated inflammatory responses, autoimmunity, bidirectional interactions with the neuroendocrine circuit, the urinary, gastrointestinal, cardiovascular and endocrine systems, in metabolism and malignancy. Thus, MCs appear to receive, integrate and transmit a wide range of signals in their microenvironment, coordinated by the differential release of their pro-inflammatory and anti-inflammatory granular mediators. Understanding the heterogeneity of this complex cellular communication may provide a tool for selective pharmacological intervention directed to specific MC subsets.
Trends in the Pharmacology of Inflammatory and Allergic Eye Disorders
Authors: Sgrulletta R. , Coassin M. , Bonini S.
Published: November 2012

Ocular allergies are one of the most common diseases presenting to the general ophthalmologist. Allergic eye disease includes a spectrum of different clinical entities: the seasonal and perennial allergic conjunctivitis and the more severe forms vernal keratoconjunctivitis and atopic keratoconjunctivitis. A wide spectrum of topical pharmacological agents has been developed for the treatment of the different forms of ocular allergy. These include mast cell stabilizers, pure antihistamines, new dual-acting agents with antihistamine and mast-cell stabilizer properties and non-steroidal antiinflammatory drugs (NSAIDs). All these drugs are very effective in controlling signs and symptoms of mild and moderate forms of allergic reaction and are mainly free of adverse reaction in the chronic use. Topical corticosteroids remain the mainstay in the aggressive treatment of sight-threatening forms of allergic conjunctivitis, although their long-term use is limited by the risk of severe ocular side effects. For this reason, newer immunosuppressive drugs, such as cyclosporine and tacrolimus, have been tested in the treatment of some forms of ocular allergy demonstrating an high safety profile. New potential therapeutic strategies include the modulation of the immune system through a switch of the allergic response from a Th2-dominated immune profile towards a Th1 response.
Anti-Inflammatory Agents in Ageing and Age-Associated Diseases
Authors: Bonovas S. , Sitaras N. M.
Published: November 2012

Ageing and inflammation might be considered as natural partners. Numerous mechanisms of an inflammatory basis for several age-associated diseases have been identified. Some markers of inflammation are already being integrated into clinical medicine. Furthermore, existent anti-inflammatory drugs and novel candidates have been found to specifically target inflammation pathways in the ageing processes. In this review, we focus on the current knowledge on the field, from the molecular and cellular level to the therapeutic potential of anti-inflammatory agents. First, we present several theories of ageing, in order to explore the involvement of inflammation and to define targets of intervention. Then, we discuss the current approaches and applications as well as the future trends in research regarding the involvement of antiinflammatory agents in the ageing processes.
Environmental Law
Authors: Sanders Dee Ann
Published: November 2012

The activity level in water‐related environmental law was relatively low during 2011, with no new or reauthorized environmental laws enacted. There continued to be concern over the environmental impacts of energy extraction and production. A significant number of multi‐million dollar enforcement actions were taken against wastewater utilities with major, continuing wet weather flow problems.
Branched-Chain and Aromatic Amino Acids Are Predictors of Insulin Resistance in Young Adults
Authors: Würtz Peter , Soininen Pasi , Kangas Antti J. , Rönnemaa Tapani , Lehtimäki Terho , Kähönen Mika , Viikari Jorma S. , Raitakari Olli T. , Ala-Korpela Mika
Published: November 2012

OBJECTIVE

Branched-chain and aromatic amino acids are associated with the risk for future type 2 diabetes; however, the underlying mechanisms remain elusive. We tested whether amino acids predict insulin resistance index in healthy young adults.

RESEARCH DESIGN AND METHODS

Circulating isoleucine, leucine, valine, phenylalanine, tyrosine, and six additional amino acids were quantified in 1,680 individuals from the population-based Cardiovascular Risk in Young Finns Study (baseline age 32 ± 5 years; 54% women). Insulin resistance was estimated by homeostasis model assessment (HOMA) at baseline and 6-year follow-up. Amino acid associations with HOMA of insulin resistance (HOMA-IR) and glucose were assessed using regression models adjusted for established risk factors. We further examined whether amino acid profiling could augment risk assessment of insulin resistance (defined as 6-year HOMA-IR >90th percentile) in early adulthood.

RESULTS

Isoleucine, leucine, valine, phenylalanine, and tyrosine were associated with HOMA-IR at baseline and for men at 6-year follow-up, while for women only leucine, valine, and phenylalanine predicted 6-year HOMA-IR (P < 0.05). None of the other amino acids were prospectively associated with HOMA-IR. The sum of branched-chain and aromatic amino acid concentrations was associated with 6-year insulin resistance for men (odds ratio 2.09 [95% CI 1.38–3.17]; P = 0.0005); however, including the amino acid score in prediction models did not improve risk discrimination.

CONCLUSIONS

Branched-chain and aromatic amino acids are markers of the development of insulin resistance in young, normoglycemic adults, with most pronounced associations for men. These findings suggest that the association of branched-chain and aromatic amino acids with the risk for future diabetes is at least partly mediated through insulin resistance.
Carotid-Femoral Pulse Wave Velocity Is Associated With Cerebral White Matter Lesions in Type 2 Diabetes
Authors: Laugesen Esben , Høyem Pernille , Stausbøl-Grøn Brian , Mikkelsen Anders , Thrysøe Samuel , Erlandsen Mogens , Christiansen Jens S. , Knudsen Søren T. , Hansen Klavs W. , Kim Won Y. , Hansen Troels K. , Poulsen Per L.
Published: November 2012

OBJECTIVE

Patients with type 2 diabetes have a high incidence of cardiovascular events including stroke. Increased arterial stiffness (AS) predicts cardiovascular events in the general population. Cerebral white matter lesions (WMLs) are associated with an increased risk of stroke. It is unknown whether AS in patients with type 2 diabetes is associated with WMLs.

RESEARCH DESIGN AND METHODS

We examined 89 patients recently diagnosed with type 2 diabetes (<5 years) and 89 sex- and age-matched controls. AS was assessed with carotid-femoral pulse wave velocity (PWV). WMLs were identified using magnetic resonance imaging and graded qualitatively with the Breteler scale (no/slight changes = 0, moderate changes = 1, severe changes = 2) and semiquantitatively.

RESULTS

The diabetic population had excellent glycemic control (HbA1c, 6.5% [6.2–6.8]; median [interquartile range {IQR}]) and had, compared with the controls, lower office blood pressure (BP) (127 ± 12/79 ± 8 vs. 132 ± 14/84 ± 10 mmHg) and total cholesterol (4.3[3.9–4.7] vs. 5.6 [5.1–6.4]; mmol/L; median [IQR]), (P < 0.01 for all). Despite this, PWV was higher in the patients with diabetes compared with controls (9.3 ± 2.0 vs. 8.0 ± 1.6 m/s; P < 0.0001). PWV was associated with Breteler score (OR 1.36 [95% CI 1.17–1.58]; P < 0.001) and WML volume (OR 1.32 [95% CI 1.16–1.51]; P < 0.001) per 1 m/s increase in PWV. These associations remained significant when adjusted for age, sex, diabetes, 24-h mean arterial BP, BMI, heart rate, and use of antihypertensives and statins (Breteler score: OR 1.28 [95% CI 1.03–1.60]; P < 0.05 and WML volume: OR 1.30 [95% CI 1.06–1.58]; P < 0.05).

CONCLUSIONS

PWV was higher among patients with well-controlled type 2 diabetes compared with controls and was independently associated with WMLs. PWV may represent a clinically relevant parameter in the evaluation of cerebrovascular disease risk in type 2 diabetes.
Effect of Er,Cr:YSGG Laser, Air Abrasion, and Silane Application on Repaired Shear Bond Strength of Composites
Authors: Cho SD , Rajitrangson P , Matis BA , Platt JA
Published: November 2012

Aged resin composites have a limited number of carbon-carbon double bonds to adhere to a new layer of resin. Study objectives were to 1) evaluate various surface treatments on repaired shear bond strength between aged and new resin composites and 2) to assess the influence of a silane coupling agent after surface treatments.

Methods

Eighty disk-shape resin composite specimens were fabricated and thermocycled 5000 times prior to surface treatment. Specimens were randomly assigned to one of the three surface treatment groups (n=20): 1) air abrasion with 50-μm aluminum oxide, 2) tribochemical silica coating (CoJet), or 3) Er,Cr:YSGG (erbium, chromium: yttrium-scandium-gallium-garnet) laser or to a no-treatment control group (n=20). Specimens were etched with 35% phosphoric acid, rinsed, and dried. Each group was divided into two subgroups (n=10): A) no silanization and B) with silanization. The adhesive agent was applied and new resin composite was bonded to each conditioned surface. Shear bond strength was evaluated and data analyzed using two-way analysis of variance (ANOVA).

Results

Air abrasion with 50-μm aluminum oxide showed significantly higher repair bond strength than the Er,Cr:YSGG laser and control groups. Air abrasion with 50-μm aluminum oxide was not significantly different from tribochemical silica coating. Tribochemical silica coating had significantly higher repair bond strength than Er,Cr:YSGG laser and the control. Er,Cr:YSGG laser and the control did not have significantly different repair bond strengths. Silanization had no influence on repair bond strength for any of the surface treatment methods.

Conclusion

Air abrasion with 50-μm aluminum oxide and tribochemical silica followed by the application of bonding agent provided the highest repair shear bond strength values, suggesting that they might be adequate methods to improve the quality of repairs of resin composites.