bluuebunny/crossref_metadata_2025 huggingface dataset:
Operational analysis of the spatial distribution and the temporal evolution of the snowpack water equivalent in southern Québec, Canada
Authors: Turcotte R. , Fortin L.-G. , Fortin V. , Fortin J.-P. , Villeneuve J.-P.
Published: July 2007

A technique for obtaining an operational regional analysis of the temporal evolution of the snowpack water equivalent in southern Québec (Canada) is proposed and implemented on a 0.1° grid. The technique combines the output of the snowpack model included in the HYDROTEL hydrological model, forced by observed temperatures and precipitations, with observed snow survey data. A strategy based on observed snow density, snowpack water equivalent and streamflow is used for model calibration. A comparison of various calibration strategies showed that the same model parameters can be used for the whole of southern Québec. It was also shown that, for operational purposes, it is sufficient to rely solely on automatic stations and to use 3 h time steps. Because snow surveys are made in deciduous forests, model parameters were adjusted to account for open areas and coniferous trees by comparing observed and simulated streamflow, using all components of the hydrological model. An assimilation technique which updates simulated water equivalent and snow density at grid points from the available snow survey data completes the operational system. An example of spring streamflow simulated using the proposed snow analysis illustrates the usefulness of the technique.
Rainfall–runoff modeling using principal component analysis and neural network
Authors: Hu Tiesong , Wu Fengyan , Zhang Xiang
Published: July 2007

The predictive accuracy of a Rainfall–Runoff Neural Network (RRNN) model depends largely on the suitability of its structure. Unfortunately, the procedures for selecting an appropriate structure for the RRNN have not been thoroughly examined. Inclusion of too many input neurons in the RRNN may complicate its structure, and thereby decrease its generalization performance. The objective of this study is to evaluate the potential of a Principal Component Analysis (PCA) method, i.e. by extracting the principal components from lagged input hydrometeorological data, in improving the predictive accuracy of the RRNN. The Darong River watershed located in Guangxi Province of China, with a drainage area of 722 km2, has been selected to demonstrate the PCA method for modeling the hourly Rainfall–Runoff (RR) relationship. Comparative tests on the forecasting accuracy were conducted among the RRNNs configured with both basin-averaged and spatially distributed rainfall information. Experimental results revealed that, when calibrating the RRNNs with spatially distributed rainfall, the RRNNs using the PCA as an input data-preprocessing tool were found to provide a generally better representation of the RR relationship for the Darong River watershed. However, variable results were observed if the neural networks had been calibrated with basin-averaged rainfall.
Using catchment models to establish measure plans according to the Water Framework Directive
Authors: Arheimer B. , Andersson L. , Alkan-Olsson J. , Jonsson A.
Published: July 2007

A participatory modelling process (DEMO) has been developed and applied in a 350 km2 catchment in southern Sweden. The overall goal is to improve the dialogues between experts and local stakeholders by using numerical models as a platform for discussions. The study is focused on reducing nutrient load and on the development of a locally established measure plan, which is requested by the European Water Framework Directive. The HBV-NP model was chosen as it can calculate effects and costs for different allocations of several combined measures in a catchment. This paper shows the impact of including local data in the modelling process vs. using more general data. It was found that modelled diffuse nutrient pollution was highly modified when including local know-how, soft information and more detailed field investigations. Leaching from arable land was found to be 35% higher using more detailed information on for instance, agricultural practices, crop and soil distribution. Moreover, the stakeholders' acceptance of model results and reliance on experts was increased by applying the participatory process and involving stakeholders in the modelling procedure.
Minimization of the diffuse pollution caused by dairy farms in Cyprus through the development of guidelines for their sustainable operation
Authors: Fatta D. , Monou M. , Voscos C. , Kythreotou N. , Stylianou Ch.
Published: July 2007

This paper summarizes the work carried out for Cyprus in respect to developing guidelines on the measures that have to be taken for the reduction of the impacts caused by the operation of dairy cow farms and in a second stage, to aid the competent authorities in permitting the dairy farms under the Water and Soil Pollution Control Law. The paper includes information on the existing situation in Cyprus in regards to: (1) the operation of the farms, the production of waste and the existing practices for the management of waste, and (2) the guidelines and measures for the reduction of waste, odours and the use of waste in order to ensure the safe and sustainable operation of the farms and the management of waste.
Surface discharge of heavy metals from low farmland
Authors: Hamada K. , Yoshinaga I. , Hitomi T. , Miura A. , Shiratani E. , Takaki K.
Published: July 2007

Runoff heavy metals from farmland were examined using the field data for the summer of 2005. The observation farmland is located on lowland where the irrigation water was contaminated with the drained water from the upstream farmlands. The area of the farmland is 11.2 ha, of which 6.0 ha and 4.5 ha have been used for rice paddy fields and soybean cultivation, respectively. During the observation, heavy metal concentrations at the downstream end were usually found to be higher than those in the irrigation water. That is, the heavy metal concentrations increased due to the passage of the water through the farmland. This increase in the heavy metal concentrations is not equal to the discharge of the heavy metal because the evaporation on the surface of the paddy field and the absorption by plants makes the surface water volume small. The discharged load from the farmland generally indicates the gross surface load from the farmland. When the effects of circulation irrigation on the heavy metal concentrations are estimated, the discharged load from the farmland should be calculated as the net surface load. When the runoff heavy metals from the circulation irrigation farmland are estimated, it is important to consider the inflowing heavy metals with irrigation water. All the heavy metal types observed in this study were discharged from the farmland. The net surface loads of Cr, Fe, Cd, and Pb were 371 μg m−2 day−1, 14.9 mg m−2 day−1, 0.26 μg m−2 day−1, and 3.3 μg m−2 day−1, respectively.
The uncertain search for the diffuse silver bullet: science, policy and prospects
Authors: Cooke J.G. , Petch R.A.
Published: July 2007

The overwhelming importance of diffuse sources as a determinant of receiving water quality has been recognised for over 30 years. Significant research and development on techniques for reducing inputs in the riparian zone has resulted in numerous guideline documents being produced. Yet despite this research effort, and the apparently successful transfer of key results to water resource managers, the public perception in New Zealand is that the quality of receiving waters continues to decline. In this paper we examine the veracity of that perception through examination of state-of-the-environment reporting, discussions with water resource managers, and published literature. Using a case study of Lake Taupo, New Zealand as an example, we discuss the difficulties faced by water resource managers in arresting declines in water quality. We compare the reduction in potential nutrient exports possible between ‘non-invasive’ mitigation techniques such as riparian buffer strips, constructed and natural wetlands and source control measures such as the use of nitrification inhibitors and wintering pads. Finally, we look at options available should voluntary measures or best management practices fail to deliver the nutrient reductions that are necessary to maintain lake water quality.
Air–water mass transfer and tracer gases in stormwater systems
Authors: Madsen H.I. , Vollertsen J. , Hvitved-Jacobsen T.
Published: July 2007

Reaeration is a central quality parameter for the performance of environmental systems such as ponds receiving urban and road runoff. Tracer gases can be used to measure reaeration rates in these systems. The methods comprise injection of a volatile tracer into an environmental system and subsequently measurement of the emission of the volatile tracer. The physical basis of such methods is the existence of a constant ratio between the air–water mass transfer coefficient for oxygen and the corresponding mass transfer coefficient for the volatile tracer gas. This constant ratio is often not clearly defined in the literature due to difficulties in both experimental procedures and handling of data. In this study such methods are evaluated and an experimental procedure and a corresponding data processing procedure for a general and reliable determination of mass transfer rates are presented. Propane is selected as an example of an appropriate tracer gas and the ratio between the mass transfer coefficients of oxygen and propane is determined.
Budgets of major ionic species and nutrients on a dam reservoir in forested watershed
Authors: Komai Y. , Umemoto S. , Takeda Y. , Inoue T. , Imai A.
Published: July 2007

To evaluate the role of a dam reservoir in the runoff of pollutant loadings from a forested watershed, the input–output budgets in the Ikuno dam reservoir had been investigated for eight years since 1996. The T-N, T-P, TOC and major ionic species in the bulk precipitation, stream water, and outflow were measured. The residence time calculated by using the data of the inflow and outflow was 0.3 year. The average precipitation was 1,772 mm during the investigation period (1996–2004). The direct deposition to water surface was less than one percentage to total loadings of nutrients and major ionic species. The ratios of output to input of TOC, TN, and TP were 1.04 to 1.42, and those of major ionic species were from 0.83 to 0.99 except for NO3−, which was 1.12. However, the ratios of output to input of major ionic species except for NO3− at the Ikuno dam reservoir will be larger, and those of NO3−, TOC, TN, and TP will be smaller, if we also include rain events. These results suggested that the dam reservoir played a role as a sink for pollutants in forested watershed, and that the pollutant loadings to downstream may decrease.
Estimation of nutrient load from urban diffuse sources: experiments with runoff sampling at pilot catchments of Lake Balaton, Hungary
Authors: Budai P. , Clement A.
Published: July 2007

About a quarter of the total nutrient loading of Lake Balaton (Hungary) originates from urban diffuse sources, mostly from direct shoreline watersheds. This load cannot be measured directly. Sampling of urban runoff can help improving load estimations. The dynamic processes characterizing the accumulation and washoff of contaminants suggest that randomly observed concentrations are likely under- or overestimated. The results of two recent pilot programs aimed towards achieving continuous measurement of nutrient load carried by urban runoff are introduced. Stations were implemented in two pilot catchments located on the shore of Lake Balaton. Storm event runoff was sampled automatically and manually. Discharge, precipitation and rainfall intensities were also recorded. Results proved that the more a specific pollutant is associated with solid particles, the more of its load comes from a few but large storm events, nevertheless the cumulative effect of small rainfall events is not negligible, either. Event mean concentrations of solid-related pollutants were found to be dependent on rainfall intensity. The derived empirical relationships for SS, TP and TN event mean concentrations were indeed found to be applicable for reducing the uncertainty of load estimations of these pollutants significantly, as compared to using long-time average (i.e. annual mean) concentration values.
Treatment of wine distillery wastewater by high rate anaerobic digestion
Authors: Melamane X.L. , Tandlich R. , Burgess J.E.
Published: July 2007

Wine distillery wastewaters (WDW) are acidic and have a high content of potential organic pollutants. This causes high chemical oxygen demand (COD) values. Polyphenols constitute a significant portion of this COD, and limit the efficiency of biological treatment of WDWs. WDW starting parameters were as follows: pH 3.83, 4,185 mg/l soluble COD (CODs) and 674.6 mg/l of phenols. During operation, amendments of CaCO3 and K2HPO4, individually or in combination, were required for buffering the digester. Volatile fatty acid concentrations were <300 mg/l throughout the study, indicating degradation of organic acids present. Mean CODs removal efficiency for the 130 day study was 87%, while the mean polyphenol, removal efficiency was 63%. Addition of 50 mg/l Fe3 +  between days 86 and 92 increased the removal efficiencies of CODs to 97% and of polyphenols to 65%. Addition of Co3 +  improved removal efficiencies to 97% for CODs and 92% for polyphenols. Optimization of anaerobic treatment was achieved at 30% WDW feed strength. Removal efficiencies of 92% and 84% were recorded at increased feed strength from days 108 to 130. High removal efficiencies of CODs and polyphenols after day 82 were attributed to the addition of macronutrients and micronutrients that caused pH stability and thus stimulated microbial activity.
Anaerobic co-digestion of winery wastewater
Authors: Rodríguez L. , Villaseñor J. , Fernández F.J. , Buendía I.M.
Published: July 2007

The operational performance of anaerobic batch reactors treating winery wastewater (WW) combined with waste activated sludge (WAS) in different proportions was investigated under mesophilic conditions. In these experiments it was shown that for anaerobic digestion of WW alone, methane production rate was lower than the rates achieved when WW and WAS were treated together. When WW was mixed with WAS at a concentration of 50% WW resulted in the highest methane production rates. A simplified anaerobic model was used to determine the main kinetic parameters; maximum COD reduction rate (qDA) and maximum methane generation rate (kmax). The maximum values of qDA and kmax were 16.50 kgCOD COD−1 d−1 and 14.34 kgCOD kgCOD−1 d−1, respectively.
Assessing the degradation of ochratoxin a using a bioassay: the case of contaminated winery wastewater
Authors: Nogueira R. , Estevinho I. , Abrunhosa L. , Mendonça C. , Machado P. , Carballa M. , Brito A.G. , Venâncio A.
Published: July 2007

In vineyards the presence of certain fungi may lead to the production of the mycotoxin ochratoxin A (OTA) and subsequent contamination of grapes and wine. Furthermore, winery wastewaters contaminated with OTA may represent an environmental hazard. Therefore, it is imperative to assess the fate of this mycotoxin in conventional wastewater treatment systems. The aim of the present work was to assess the biological degradation of OTA. Experimental work was carried out in batch experiments with initial OTA to biomass concentration ratios of 1.4 μg mg−1, 7.4 μg mg−1 and, 11.9 μg mg−1. The assays were inoculated with activated sludge biomass unadapted to the substance under examination. The proposed bioassay demonstrates that OTA concentrations up to 100 μg L−1 can be degraded by microbial activity in activated sludge.
Continuous and sequencing membrane bioreactors applied to food industry effluent treatment
Authors: Lobos J. , Wisniewski C. , Heran M. , Grasmick A.
Published: July 2007

This work focuses on the performances of two immersed membrane bioreactors used for the treatment of easily biodegradable organic matter present in food industry effluents, for the purpose of water reuse. Two reactor functioning modes (continuous and sequencing) were compared in terms of organic carbon removal and of membrane permeability. For each working mode, pollutant removal was very high, treated water quality presented a low COD concentration (<125 mg.L−1), no solids in suspension and low turbidity (<0.5 NTU). The quality of the treated water (including germ removal) enabled its reuse on site. Moreover, by developing high biomass concentrations in the reactor, excess sludge production remained very low (<0.1 gVSS.gCOD−1). The performances appeared slightly better for the continuous system (lower COD concentration in the effluent, <50 mg.L−1, and lower sludge production). In terms of filtration, a distinct difference was observed between continuous and sequencing systems; transmembrane pressure showed a small and constant evolution rate in continuous membrane bioreactor (CMBR) although it appeared more difficult to control in sequencing membrane bioreactor (SMBR) probably due to punctually higher permeate flow rate and modified suspension properties. The rapid evolution of membrane permeability observed in SMBR was such that more frequent chemical cleaning of the membrane system was required.
Heavy metal removal from winery wastewater in the case of restrictive discharge regulation
Authors: Andreottola G. , Cadonna M. , Foladori P. , Gatti G. , Lorenzi F. , Nardelli P.
Published: July 2007

In most cases of winery effluent, the heavy metal content, especially zinc (Zn) and copper (Cu), does not meet the limits for the discharge as imposed by the most restrictive regulations at international level (0.4 mgCu/L and 1.0 mgZn/L in the Italian regulations). An alternative for the reduction of Cu and Zn is the on-site pre-treatment of wastewater at the winery in order to meet the limits for the discharge into the public sewerage. The purpose of this study is to evaluate the effectiveness of a pre-treatment based on chemical precipitation with chelating agents (TMT: 2,4,6-trimercaptotriazine), for the reduction of Cu and Zn from raw winery wastewater. The chemical precipitation was optimised at lab-scale through jar tests in order to evaluate the optimal dosages. An average dosage equal to 0.84 mL of TMT (15%) for 1 mg of Cu removed was estimated. Furthermore, the efficiency of the on-site chemical pre-treatment was investigated at pilot scale. The results confirmed the feasibility of using TMT treatment for the reduction of Cu and Zn in order to meet the limits for discharge into the sewerage. Contextually to the removal of heavy metals, the chemical pre-treatment allowed us to obtain the reduction of particulate COD and TSS. Finally, the costs for the operation and the management of the on-site pre-treatment were evaluated.
Characterization, management and treatment of wastewater from white wine production
Authors: Fernández B. , Seijo I. , Ruiz-Filippi G. , Roca E. , Tarenzi L. , Lema J.M.
Published: July 2007

During a 16 months period, the characteristics of the wastewaters generated in a Rias Baixas winery (Spain) producing white wine were determined: The characterization study showed that white wine wastewater had an average CODt and TSS values of 7.3 and 5.2 kg/m3, respectively being the ratio wastewater/wine produced of about 1.6–2.0 L/L and the ratio between load pollution and produced wine of 9.7 kgCODt/m3WINE. A strategy for the management of wastes and wastewaters allowed for an important reduction of a 55% of wastewater generation to be achieved. In order to select a suitable technology for the treatment of wastewaters two configurations were tested at pilot scale: i) An Anaerobic Filter (AF) of 430 L followed by an activated sludge unit of 510 L and: ii) one activated sludge unit of 510 L. The results showed that the anaerobic/aerobic configuration was more flexible as it adapted quickly to the different loads and flows produced during the different phases through the year. Besides it allowed higher COD removals (98.5–99.2%) to be achieved and proved to permit a quicker re-start up after starvation periods.
Use of modelling to evaluate best control practice for winery-type wastewaters
Authors: Batstone D.J. , Steyer J.-P.
Published: July 2007

Winery wastewaters are high strength, and readily biodegradable, making them perfect for application of anaerobic digestion. However, inherent buffering against pH changes also requires some process knowledge and monitoring. They are therefore an important target for anaerobic process control. This has had limited application, but is emerging as an important research and development area. In this paper, we evaluate the use of model-based control analysis of a heavily loaded vinasse-fed reactor. Two controllers – both proportional-integral (PI) – on total volatile fatty acids (VFA) (<500 mg/L), alkalinity (VFA/Total Alkalinity < 0.2) were evaluated in a fitted model, against the actual control mechanism used, which was model-based adaptive control. The two controllers were both less aggressive than the adaptive controller, producing less gas overall, but also using more caustic for pH control. The controllers were also evaluated against their ability to deal with noise, as PI controllers are relatively poor for controlling non-linear processes. The VFA controller was very poor with noise added, proving difficult to tune, and oscillatory. The alkalinity controller was effective with moderate detuning. This emphasizes the need to use effective controller inputs, when applying simple, linear controllers. Overall, use of a model was an effective method to evaluate the different controllers in a competitive way, in a standardized environment.
The impact of CCA-treated posts in vineyards on soil and ground water
Authors: Greven M. , Green S. , Robinson B. , Clothier B. , Vogeler I. , Agnew R. , Neal S. , Sivakumaran S.
Published: July 2007

Grapes in Marlborough are typically grown on a vertical shoot positioned trellis system (VSP). For this purpose Pinus radiata posts are treated with CCA, a mixture of copper (Cu), chromium (Cr) and arsenic (As), giving a wood concentration of 1,730, 3,020 and 2,410 mg/kg, respectively on a dry matter basis. The CCA levels around the posts in different soils were investigated and assessed for the potential leaching of CCA into ground water. An initial survey showed leaching of all three heavy metals from the treated posts into the soil surrounding the posts (0.2% of the total vineyard area) compared with the control, depending on vineyard age and soil type. The rate of movement out of the posts was calculated from posts placed in lysimeters. HortResearch's Soil Plant Atmosphere Model (SPASMO) was used to predict the leaching rate of CCA. For As, leaching was found to be 5 mg/post/month, with the Cr rate being about twice that. Further modelling revealed a steady plume of As moving downwards after about 200–300 years. However, long-term hydrogeological modelling showed that sufficient aquifer water flow prevented the accumulation of CCA in the ground water. The modelling approaches are discussed.
Evaluation of six pesticides leaching indexes using field data of herbicide application in Casablanca Valley, Chile
Authors: Kogan M. , Rojas S. , Gómez P. , Suárez F. , Muñoz J.F. , Alister C.
Published: July 2007

A field study was performed to evaluate the accuracy of six pesticide screening leaching indexes for herbicide movement. Adsorption, dissipation and soil movement were studied in a vineyard in a sandy loam soil during 2005 season. Simazine, diuron, pendimethalin, oxyfluorfen and flumioxazin were applied to bare soil at rates commonly used, and their soil concentrations throughout soil profile were determined at 0, 10, 20, 40 and 90 days after application (DAA). Herbicides were subjected to two pluviometric regimens, natural field condition and modified conditions (plus natural rainfall 180 mm). Leaching indexes utilized were: Briggs's Rf, Hamaker's Rf, LEACH, LPI, GUS and LIX. Simazine reached 120 cm, diuron 90 cm, flumioxazin 30 cm soil depth respectively. Pendimethalin and oxyfluorfen were retained up to 5 cm. None of the herbicides leaching was affected by rainfall regimen. Only flumioxazin field dissipation was clearly affected by pluviometric condition. The best representation of the herbicide soil depth movement and leaching below 15 cm soil depth were: Hamaker's Rf < Briggs's Rf<GUS<LPI,<LEACH<LIX. Field results showed a good correlation between herbicides Kd and their soil depth movement and mass leached below 15 cm soil depth.
Dynamics of the Cross-Country Growth/Volatility Relationship
Authors: Edwards Jeffrey A.
Published: July 2007

This study evaluates structural changes over time in the cross-country relationship between growth and volatility. Using a GMM 2SLS method to control for endogenous variables, and a time-series based rolling window estimation procedure, this study adds to the current literature in two significant ways. The first is that to assume the cross-country growth/volatility correlation is constant over time, or differs across ad hoc predetermined intervals of time is inappropriate. Instead, the early to mid 1990's seems to be the primary area whereby there are significant changes in the relationship across countries. Specifically, volatility negatively impacted growth for developed nations around this time, while it positively impacted growth for developing nations--the latter happening a few years later than the former. The second finding is that the positive impact that trade had on the growth/volatility relationship for developing countries during this period is outweighed by the negative impact of gross capital flows. Among developed nations, globalization reduces a negative effect that gross capital flows has on the relationship. For policy and constituency appeasement purposes the former is an argument for caution when entering into the global economy, and the latter an argument to embrace it.
Zeolite Formation from Expanded Perlite Using Hydrothermal Treatment with Alkaline Solutions of NaCl: A Kinetic Study of the Process
Authors: Destéfanis Hugo A , Erdmann Eleonora , Acosta Delicia E
Published: July 2007

Amorphous natural silicoaluminates, such as expanded perlite, transform themselves in three-dimensional crystalline species, exhibiting effects of the alkaline solutions with NaCl. In this paper the kinetics and the effect of the reaction conditions over the crystallization process are studied.Na(OH) solutions 15%, 18%, and 20 % w/v, and NaCl solutions from 0 % up to 30 % w/v were used. Temperature range was from 80ºC to 95 ºC. The effect of the solid/liquid relationship and the fluid dynamic conditions were studied. The rate of the zeolite formation process depends on the concentration of Na(OH) / NaCl solutions and on the reaction temperatures.The fluid dynamic conditions and the solid/liquid relationships have no effect over the crystallization process in the studied range. The effect of the NaCl is to increase the reaction rate independently of the kind of obtained zeolite, which is associated with the relationship Si/Al.Powder X  ray diffraction (XRD) analysis and scanning electron microscopic (SEM) were employed to study the zeolite formation process in order to elucidate the mode of zeolite crystallization.The mechanism implies the formation of units of nuclei of growth, and the population of these units is controlled by NaCl concentrations. The nucleation and growth Avrami model properly describes the process of formation of the crystalline species. It is found that the parameters k and n are linked respectively with the conditions and the reaction mechanism.
Effects of Surfactant Composition and Concentration on Shape, Size and Photocatalytic Activity of TiO2 Nanoparticles
Authors: Liao Dongliang , Liao Baoqiang
Published: July 2007

Various shapes and sizes, including spherical, cubic nanoparticles and hexagonal nanorods with the dimensions of 50-500nm, of TiO2 were prepared through hydrolysis of titanium butoxide in sol-gel method with the introduction of different surfactant composition and concentrations during preparation. Prepared TiO2 nanoparticles were studied for photocatalytic decomposition of methyl orange (MO) in fixed film batch reactors. The results showed that shape, size and photocatalytic activity of TiO2 depend not only on surfactant composition but also on surfactant concentration. Photocatalytic decomposition of MO followed the first order kinetic reaction. The analysis of reaction rate constants showed that the shape is more important than the size in determining the photocatalytic activity of shape- and size-controlled TiO2 nanoparticles. TiO2 nanorods had higher photocatalytic activities than spherical and cubic TiO2 nanoparticles.
Biofiltration of Volatile Organic Compounds by a Fluidized Bed of Sawdust
Authors: Delebarre Arnaud , Andres Yves , Pellerano Mario , Pero Patrizia , Garcia Munzer David Gerardo
Published: July 2007

In this study, the use of a natural material, sawdust, in a fluidised biofiltrer has been considered. The performance of the biofiltration of ethanol and toluene was estimated in the presence of the native microorganisms of the material and also after the addition, and a period of acclimatization, of external microorganisms. Modifications of the physical and biological characteristics of the material were studied in order to better understand the process. The influence of biofilter shutdown periods was also considered to evaluate the effect of a period of inactivity on subsequent performances.This study shows that a significant degradation of the pollutants is obtainable provided that the following steps are performed: seeding with activated sludge, introduction of nutrients, and control of the changes in the material characteristics and the bed moisture.During the operation of the fluidized bed biofilter, the moisture of the bed had an important effect on the biofilter performance, but was rather difficult to control because of its dependence on the ambient and inlet air temperatures, which changed during the day and the seasons. During the tests with the batch of sawdust particles used as delivered without any sludge enrichment, a reduction in abatement performances was measured with time. In the case of ethanol alone, for a concentration of 0.02 g.m-3, abatement decreased from 24% to 18% then to 7%. The partial or complete addition of sawdust particles previously activated with sludge significantly enhanced the performance of the biofilter, both for ethanol and toluene pollution. Abatements of ethanol of 85% and 60% were achieved when the sawdust particles were activated by sludge. In contrast, a 5-week shutdown of the reactor produced a decrease in abatement, either by a loss of microorganism efficiency during their "starvation" or by their destruction.
Production of Sludge in a Submerged Membrane Bioreactor and Dewatering Aspects
Authors: Khongnakorn Watsa , Wisniewski Christelle
Published: July 2007

In wastewater treatment, the membrane bioreactor (MBR) holds the potential to become one of the new generation processes, ensuring effluent quality and disinfection of sufficiently high levels to allow water reuse and recycle. Furthermore, the possibility to operate with high biomass concentrations (2 to 5 times higher than in conventional activated sludge process, CAS) allows to impose high solid retention times(SRT) that can be beneficial to a sludge production reduction and so to a reduction of disposal costs. These non-conventional operating conditions (high SRT) can also induce different sludge characteristics and dewatering aptitude, which are essential parameters for the optimization of the sludge post-treatment, like mechanical dewatering. The objective of this work was to study the performances of a complete sludge retention membrane bioreactor, in terms of organic removal efficiency, sludge production and sludge dewaterability. The adaptability of Activated Sludge Model 3 (ASM3) to provide good prediction results of high SRT-MBR was studied. Typical parameters adopted to describe sludge dewaterability were quantified and compared with the conventional activated sludge process (CAS).
The Experiences of Irish Nurse Lecturers Role Transition from Clinician to Educator
Authors: Dempsey Laura M
Published: July 2007

Described in this study are the experiences of six clinical nurses in Ireland who have transitioned to the role of nurse lecturer. Semi-structured interviews were used to gather data from these novice nurse lecturers. Data were analyzed manually and thematically, generating five emerging themes: feelings experienced during the transition; educational preparation for the role; actual and potential support structures available; hindering factors of the role; and the overall transition experience. Negative feelings and experiences encountered were found to decrease as participants accepted their role change, gained experience in their new role, and became more familiar with their work environment.
Reply to Kendall: Asking v. Story-Spinning
Authors: Bergmann Barbara R.
Published: July 2007

The idea that economists will come closer to the reality of business operations by sitting in their academic offices and making up stories than they might get by observing or talking to managers is bizarre.
Functional Effect of Fully Hydrogenated Palm Oil-based Emulsifiers on Baking Performance of White Bread
Authors: Chin Nyuk L , Goh Suit K , Rahman Russly A , Hashim Dzulkifly M
Published: July 2007

Breadmaking experiments were undertaken to investigate the effect of addition of selected fully hydrogenated palm oil-based emulsifiers (DATEM, SSL and DMG) on the baking performance of open top white breads in terms of volume, oven spring, weight, density, color, crumb texture and shelf life using the strong and weak flours. The bread samples were prepared using straight dough method with standardized formulation for every experiment except varying six usage levels of emulsifier from 0.0% (control sample) up to 1.25% based on flour weight. The properties of bread were objectively measured and quantitatively analyzed using analysis of variance (ANOVA) with 5% significance level. Emulsifier performed most effectively at a usage level of 0.50% of flour weight. DATEM was effective as volume and oven spring improver while SSL was effective in improving crumb texture. As overall, emulsifier added breads had larger volume, higher oven spring, lower weight and density, whiter color, finer crumb texture and longer shelf life compared to control breads. The improvement in baking performance with added emulsifier was more prominent for the strong flour compared to weak flour.
Crisp and Fuzzy Optimisation Approaches for Water Network Retrofit
Authors: Hul Seingheng , Ng Denny K. S. , Tan Raymond R , Chiang Choon-Lai , Foo Dominic C. Y.
Published: July 2007

Material reuse/recycle has gained much attention in recent years for both economic and environmental reasons. Process integration techniques for water network synthesis have evolved rapidly in the past decade. With in-plant water reuse/recycle, fresh water and wastewater flowrates are reduced simultaneously. In this work, linear programming and mixed integer linear programming models that include piping cost and process constraints are developed to retrofit an existing water network in a paper mill that was not originally designed with process integration techniques. Five scenarios are presented, each representing different aspects of decision-making in real process integration projects. The fifth scenario makes use of fuzzy optimisation to achieve a compromise solution that considers the inherent conflict between maximising water recovery and minimising capital cost for retrofit.
The Pollution Haven Paradox: Can an Effluent Tax Improve both Profits and Welfare?
Authors: Driskill Robert , Horowitz Andrew W.
Published: July 2007

Stringent environmental taxes in high-income countries are assumed to drive dirty industries to low-income countries, but the empirical evidence for ``pollution havens" is surprisingly weak. We demonstrate that a government trying to prevent flight by a ``dirty" durable good monopolist can impose an effluent tax that is offset by a lump-sum subsidy so that both firm profits and host-country welfare are increased. The scheme exploits the Coase Conjecture insight: a durable goods monopolist has a time-consistency dilemma that limits its ability to restrict future output. In this environment the effluent tax provides a credible commitment that restricts future supply. We assert that the use of lump-sum subsidies in strategic location competition is consistent with this mechanism, and this paradigm may be an important piece of the ``pollution haven paradox."
Human Capital and Welfare Dynamics in Canada
Authors: Hansen Jorgen
Published: July 2007

This paper analyzes the effects of human capital on welfare dynamics in Canada using data from the Self-Sufficiency Project (SSP). SSP offered a time-limited earnings supplement to a randomly assigned group of new welfare applicants who remained on welfare for one year and, in the subsequent year, left welfare for full-time employment. The results suggest that high school completion has no significant impact on the exit rate from welfare or on the re-entry rate. Moreover, full-time work experience is found to reduce the risk of returning to welfare but not for respondents who were assigned to the treatment group. This finding suggests that the provision of an earnings subsidy encourages welfare recipients to accept low-wage jobs with little gains from work experience. Thus, the rationale for such a policy that work today will raise experience and consequently future wages is not supported by the results in this paper.
Democracy's Dividend: Political Order and Economic Productivity
Authors: Faust Jörg
Published: July 2007

There is a broad consensus in the social sciences that political institutions have a strong impact on economic development. There is no such consensus, however, about the specific influence of democratic order on economic performance. Based on arguments derived from economic institutionalism, this paper shows that democracy has a positive impact on productivity growth. In contrast to autocratic systems, a democratic order can be interpreted as a competition-friendly regulation of a natural monopoly, which results in comparatively high productivity gains. This hypothesis is supported by quantitative tests for a sample of 81 countries for the period of 1975-2000, which show that increasing levels of democracy generate a productivity dividend.
Politics of Childhood, Democracy and Communal Life: Conditions of Political Socialisation and Education
Authors: Sünker Heinz , Swiderek Thomas
Published: July 2007

Conditions of children's political socialisation and education have more than ever in the last 40 years to deal with questions of social inclusion and exclusion. This is a result of social cleavages which are pertinent for children's lives and experiences. This article deals with this question while favouring an approach which shows that a strengthening of children's rights – based on an emancipatory concept of politics of childhood – could support the struggle against these cleavages in the interest of establishing a really democratic society. A central starting point for an improvement of the situation of all children could be a new connection between communal life and childhood policies. Therefore the article shows different approaches which work on this level and argues for their generalisation. When the future of mankind is at stake, only a democratisation of society/ies – based on enlisting the competencies of all citizens (including children) – can be useful. This is the major challenge for political education.
A Zone for Deliberation? Methodological Challenges in Fields of Political Unrest
Authors: Westrheim Kariane , Lillejord Sølvi
Published: July 2007

This article outlines certain problems and challenges facing the qualitative researcher who enters fields that are either extremely difficult to access or potentially hostile towards outsiders. Problems and dilemmas in such contexts are highlighted by reference to fieldwork research among PKK (Kurdistan Worker's Party) guerrillas in North Kurdistan, Turkey. The article is part of a larger study on knowledge production and identity development in the PKK. The theoretical foundation draws on the Freirian tradition that is also labelled emancipatory or liberating research. The article discusses challenges within this particular line of research and presents the idea of a ‘zone for deliberation’ as a potential arena for developing intersubjective understanding in cases when the experiences of informants and interviewer are culturally and politically diverse.
Exposure to Community Violence and Political Socialization among Adolescents in Northern Ireland
Authors: Shepherd Linda
Published: July 2007

This study evaluates the effects of adolescent exposure to cross-community violence, intense paramilitary operations, aggression, and intimidation in Northern Ireland. Using publicly available survey data gathered by agencies in Northern Ireland, the research examines the effects of exposure to political violence with focus upon the manner by which adolescents have become politically socialized, the development of political attitudes, and the presence and level of psychological responses to this environment. Special attention is paid to cultural context, gender, and religious differences.
Life cycle of the nematode Contracaecum rudolphii Hartwig, 1964 (sensu lato) from northern Poland under laboratory conditions
Authors: Dziekońska-Rynko J. , Rokicki J.
Published: July 2007

The study was aimed at following, under laboratory conditions, embryogenesis of the nematode Contracaecum rudolphii, and at identifying its intermediate hosts in northeastern Poland. Nematode eggs, isolated from the terminal part of the female uterus, were placed in 0.9 and 3% NaCl solutions, 1% formalin, and in tap water. Each solution batch was divided into 3 parts kept at 4, 15, and 23°C. Regardless of the temperature they were exposed to, the eggs placed in 1% formalin showed numerous deformations; as few as 5% of those eggs produced larvae. Embryogenesis was at its fastest in the eggs kept at 23°C. While still within the eggs, the larvae underwent two moults. The eggs hatched to produce the stage 3 larvae, which emerged surrounded by the cuticle of the preceding larval stage. Experimental infestations of zooplankton collected from Lake Kortowskie showed that only cyclopoid copepods could serve as the intermediate hosts. No differences in the infestation intensity were found between the guppies infested by the invasive larvae and those fed the infested cyclopoids.
The helminth community of the Mediterranean mouse, Mus spretus, in a post-fire regenerated Mediterranean ecosystem
Authors: Sainz-Elipe S. , Galán-Puchades M. , Fuentes M.
Published: July 2007

The helminth community of the Mediterranean mouse, Mus spretus, was analysed in a post-fire regenerated Mediterranean ecosystem. The study was carried out in the Spanish Natural Park of the Serra Calderona and comprised a 13 year period, from the 2nd to the 14th year after a wildfire. A total of 121 host individuals was analysed, 66 mice from the burned area and 55 from the non-burned area used as control. The results show a helminth community consisting of 10 helminth species, characterised by low diversity, with Syphacia obvelata as the only dominant helminth species. The helminth infracommunity, determined by its origin of capture, burned or non-burned areas, shows some significant differences. It is concluded that the helminth community of the Mediterranean mouse could be considered as a potential biological tag of the post-fire regeneration in Mediterranean ecosystems and therefore might explain some of the changes occurring and their repercussions in perturbed areas.
Study of the 49 kDa excretory-secretory protein gene of Trichinella nativa and Trichinella spiralis
Authors: Zheng B. , Xiao L. , Wang X. , Li D. , Lu Y. , Zhang Y. , Yan Q. , Song M.
Published: July 2007

To study the function of the 49 kDa excretory-secretory (ES) protein gene (P49) of Trichinella, the genes was amplified by RT-PCR from RNA of Trichinella spiralis and Trichinella nativa and several Chinese Trichinella isolates of domestic animals, and sequenced after being cloned. The amplified products of these parasites produced bands of about 950 bp. The 97.2 % to 100 % nucleotides identity and 94.3 % to 100 % identity of deduced amino acids among P49 gene of these Trichinella strains showed the close relationship of these parasites. The P49 gene of T. nativa was cloned into the BamHI site of the prokaryotic expression vector pET-30a, and the recombinant vector was expressed. The expressed product was 40.8 kDa in size. In Western blot analysis, the expressed product was reactive to sera of mice infected with T. nativa, T. spiralis and their Chinese geographical strains.
The role of the colostrum and milk in Neospora caninum transmission
Authors: Moskwa B. , Cabaj W.
Published: July 2007

Neospora caninum, an apicomplexan protozoan causes economical losses due to reproductive failure associated with abortion among cattle. The transmission of N. caninum is possible through vertical transmission in utero, or according to the modern nomenclature endogenous and exogenous infection modes and horizontal transmission through ingestion of oocysts. Limited data is available on the vertical transmission during suckling time, via colostrum and milk.

In this paper the main scientific aim focused on N. caninum DNA detection in the milk and colostrum of seropositive cows have been reviewed. In this term, the risk of animals and humans infection has been discussed.
New K-Ar Cooling Ages of Granitoids from the Strzegom-Sobótka Massif, SW Poland
Authors: Turniak Krzysztof , Halas Stanislaw , Wójtowicz Artur
Published: July 2007

The Strzegom-Sobótka Variscan Massif (Fore-Sudetic Block, NE Bohemian Massif) consists of various post-kinematic Variscan granitoids emplaced into Palaeozoic low grade metamorphic rocks. Biotite from five samples representing the hornblende-biotite monzogranite, biotite monzogranite and biotite granodiorite has been dated using the K-Ar method for two size-fractions (0.25-0.35 and 0.35-0.5 mm). Finer fractions show more intense chloritization and therefore the results for them were rejected in further discussion. Coarser fractions with higher potassium content were accepted as yielding a maximum estimate approaching the true K-Ar biotite cooling ages. The results are clustered in two groups. The older age group (308.8±4.6 Ma and 305.5±4.3 Ma) comprises results obtained from the biotite granodiorites. They are generally consistent with the zircon crystallization age of 308.4±1.7 Ma reported by Turniak et al. (2005) and imply rapid cooling of the biotite granodiorite from magmatic temperatures down to the closure temperature of K-Ar isotopic system in biotite. The younger group is defined by 291.0±4.4 Ma and 298.7±5.2 Ma ages for the hornblende-biotite monzogranite and 294.2±4.3 Ma age for the biotite monzogranite. In the absence of precise U-Pb or Pb-Pb zircon data further geochronological studies are needed to decipher precisely the cooling history of the monzogranites.
Lithology of the Profundal Sediments in Słupiańska Bay (Wigry Lake, NE Poland) - Introduction to Interdisciplinary Study
Authors: Rutkowski Jacek , Król Katarzyna , Szczepańska Jadwiga
Published: July 2007

In this paper, a lithological study taking into account trace metals of the profundal sediments from Słupiańska Bay in Wigry Lake is presented. A profile 5.26 m long has sandy muds at the bottom and moving upwards layers of calcareous gyttja, lacustrine chalk, and again calcareous gyttja are present. The profile is continuous, typical for the sediments of NE Poland formed from Allerøde to recent time. The results of the lithological analysis were correlated with results of high-resolution seismic survey. The results together with radiocarbon dating are part of interdisciplinary complex research comprising paleobiological study of pollen, Cladocera, diatom successions and human activity, which will be published in successive papers.