bluuebunny/crossref_metadata_2025 huggingface dataset:
Towards a Model for Side Access Free Grid Resources by Means of Virtualized Data Grids
Authors: Huemer David , Tjoa A Min , Descher Marco , Feilhauer Thomas , Masser Philip
Published: April 2011

Sharing data within Grid environments can potentially result in losing control over data usage. If the shared information is medical data laws must be followed, enabling tightly controlled, reconstructible access. To comply with these regulations it must be guaranteed, that each data access and modification is recorded to enable audit trails. The provided solution introduces a new concept for virtualized Data Grid environments which consist of a secure virtual machines, harnessing secure data hosting and indemnifying thorough audit trails by logging each data interaction. This solves the problem of traceability and side-access.
Community Oriented Neighboring Feedback for Efficient End-to-End Delay-Sensitive MP2P Streaming via Temporal Relay-Based Replication
Authors: Mavromoustakis Constandinos X. , Karatza Helen D.
Published: April 2011

Next generation peer-information systems are envisioned to be characterized by an invisible and ubiquitous lookup application support which should be easily accessible by users in a transparent and location-independent reliable fashion. Therefore, the traditional end-to-end delays should be bounded and minimized in order to offer significant increase in performance and reliability in today's Mobile Peer-to-Peer (MP2P) systems. Many parameters that affect the end-to-end delay for efficient collaborative streaming, deal with the temporal characteristics (connectivity and mobility constraints, etc). These parameters are significantly degrading the end-to-end communicational survivability and resources' availability. In this work a scheme for collaborative replication is proposed using community oriented relay regions for MP2P streaming. The proposed model considers a combined community oriented neighboring feedback approach with selective delay-centric replication taking into account the social interactions for assigning available resources to nodes that are communicating via intraclustered links. The collaborative streaming is achieved through the outsourcing file chunk policy for N-hop replicated sources and the combined community oriented model. The presented scheme is thoroughly evaluated through experimental simulation which takes measures for the end-to-end reliability and the latency of the broadcast schedule when delivering delay-sensitive MP2P streams.
Performance Evaluation of a Hybrid Programming Model for RSDFT on T2K Open Supercomputer
Authors: Tsuji Miwako , Sato Mitsuhisa
Published: April 2011

Non-uniform memory access (NUMA) systems, where each processor has its own memory, have been popular platform in high-end computing. While some early studies had reported that a flat-MPI programming model outperformed an OpenMP/MPI hybrid programming model on SMP clusters, the hybrid of a shared-memory, thread- based programming and a distributed-memory, message passing programming is considered to be a promising programming model on the multi-core multi-socket NUMA clusters. We explore the performance of the OpenMP/MPI hybrid programming model on a large scale multi-core multi-socket cluster called T2K Open Supercomputer to reveal the nature of the hybrid programming model on such clusters. We extend the Real-Space Density Functional Theory (RSDFT) code to the OpenMP/MPI hybrid version. We show and discuss the performance for several routines in RSDFT code which have different characteristics in operation and communication.
New Trends in Large Scale Distributed Systems Simulation
Authors: Dobre Ciprian , Pop Florin , Cristea Valentin
Published: April 2011

In this paper we present recent developments in the domain of modeling and simulation of large scale distributed systems (LSDS). Such systems possess features that include resource sharing, openness, concurrency, scalability, fault-tolerance, and transparency. The use of simulators for evaluating different methods or techniques designed for such systems is appealing due to factors such as reduced costs or time, diversity of modeling scenarios, and others. Recently several simulators where developed to model large scale distributed systems, considering their particular characteristics. In this work we present an analysis of simulators' properties, considering their design characteristics and the particularities of the used simulation models. We emphasize the pros and cons for each of the surveyed simulators, and present our approach in developing a generic simulator for large scale distributed systems. We also present a vision for future trends in this domain.
An Algorithm for Rough Surface Generation with Inhomogeneous Parameters
Authors: Uchida Kazunori , Honda Junichi , Yoon Kwang-Yeol
Published: April 2011

This paper is concerned with an algorithm for generating the inhomogeneous random rough surface (RRS) that can simulate the physical environments such as desert, vegetable field, sea surface and others, better than the homogeneous RRS. First, we discuss the statistics for two-dimensional (2D) RRSs with arbitrary types of spectra. Second, we review the essence of the convolution method which is flexible and effective for generation of various kinds of RRSs. Finally, we propose an algorithm for inhomogeneous RRS generation by modifying the convolution method. Numerical examples are also given for some inhomogeneous RRSs.
Effects of Diffracted Waves by Two Horizontal Edges in Propagation Path of a Wireless Communication Network
Authors: Iwashige Jiro , Barolli Leonard
Published: April 2011

In order to have an effective utilization of the radio wave resources, it is important to estimate propagation path in the urban area. In our previous work, we have examined the diffracted fields by two horizontal edges with an arbitrary angle which are in different and same heights, when a source is located lower than the height of the edges. In this paper, we compare the strength of the direct field, single and double diffracted fields, when the height of the source is varied. Furthermore, the effect of frequency change to the diffracted field is discussed. The numerical calculations are carried out for two wedges and a building-like double-wedge on perfect conductor, concrete and earth wedges. The results show that the higher the source is located, the stronger the diffracted fields become, and the frequency change has not a significant effect to the total field.
Parallel Simulations of Dynamic Earthquake Rupture along Geometrically Complex Faults on CMP Systems
Authors: Wu Xingfu , Duan Benchun , Taylor Valerie
Published: April 2011

Chip multiprocessors (CMP) are widely used for high performance computing and are being configured in a hierarchical manner to compose a CMP compute node in a CMP system. Such a CMP system provides a natural programming paradigm for hybrid MPI/OpenMP applications. In this paper, we use OpenMP to parallelize a sequential earthquake simulation code for modeling spontaneous earthquake rupture along geometrically complex faults on two CMP systems, IBM POWER5+ system and SUN Opteron server. The experimental results indicate that the OpenMP implementation has the accurate output results and the good scalability on the two CMP systems. We apply the optimization techniques such as large page and processor binding to the OpenMP implementation to achieve up to 7.05% performance improvement on the CMP systems without any code modification. Further, we illustrate an element-based partitioning scheme for explicit finite element methods. Based on the partitioning scheme and what we learn from the OpenMP implementation, we discuss how efficiently to use hybrid MPI/OpenMP to parallelize the sequential earthquake rupture simulation code in order to not only achieve multiple levels of parallelism of the code but also to reduce the communication overhead of MPI within a CMP node by taking advantage of the shared address space and on-chip high inter-core bandwidth and low inter-core latency. Our initial experimental results indicate that the hybrid MPI/OpenMP implementation obtains the accurate output results and has good scalability on CMP systems.
CUDA Memory Optimizations for Large Data-Structures in the Gravit Simulator
Authors: Siegel Jakob , Ributzka Juergen , Li Xiaoming
Published: April 2011

Modern GPUs open a completely new field to optimize embarrassingly parallel algorithms. Implementing an algorithm on a GPU confronts the programmer with a new set of challenges for program optimization. Especially tuning the program for the GPU memory hierarchy whose organization and performance implications are radically different from those of general purpose CPUs; and optimizing programs at the instruction-level for the GPU.

In this paper we analyze different approaches for optimizing the memory usage and access patterns for GPUs and propose a class of memory layout optimizations that can take full advantage of the unique memory hierarchy of NVIDIA CUDA. Furthermore, we analyze some classical optimization techniques and how they effect the performance on a GPU.

We used the Gravit gravity simulator to demonstrate these optimizations. The final optimized GPU version achieves a 87× speedup compared to the original CPU version. Almost 30% of this speedup are direct results of the optimizations discussed in this paper.
Modeling and Simulation of a Screw-Worm Gear Mechanical Transmission to Achieve its Optimal Design under Imposed Constraints
Authors: Suciu Claudiu V. , Goto Hozumi , Abiru Hisanori
Published: April 2011

This work deals with the modeling and simulation of a screw-worm gear mechanical transmission (worm gear screw jack), abbreviated WGSJ, to achieve its optimal design under imposed constraints. Optimal design is sought under two different conditions: to maximize the efficiency of WGSJ, for energy saving, and to minimize the overall size of WGSJ, for compact design. Several different models of buckling for the screwed shaft are taken into account by introducing a variable coefficient of fixity. Different strength theories of failure for the screwed shaft are taken into account, according to the type of material used, by introducing a variable weighting coefficient of the shear stress relative to the normal stress in evaluation of the equivalent stress. Variation of the mechanical transmission's efficiency and its overall size versus the coefficient of fixity and the shear stress weighting coefficient are presented and discussed.
Interaction between FLASH and Lsm11 is essential for histone pre-mRNA processing in vivo in Drosophila
Authors: Burch Brandon D. , Godfrey Ashley C. , Gasdaska Pamela Y. , Salzler Harmony R. , Duronio Robert J. , Marzluff William F. , Dominski Zbigniew
Published: April 2011

Metazoan replication-dependent histone mRNAs are the only nonpolyadenylated cellular mRNAs. Formation of the histone mRNA 3′ end requires the U7 snRNP, which contains Lsm10 and Lsm11, and FLASH, a processing factor that binds Lsm11. Here, we identify sequences in Drosophila FLASH (dFLASH) that bind Drosophila Lsm11 (dLsm11), allow localization of dFLASH to the nucleus and histone locus body (HLB), and participate in histone pre-mRNA processing in vivo. Amino acids 105–154 of dFLASH bind to amino acids 1–78 of dLsm11. A two-amino acid mutation of dLsm11 that prevents dFLASH binding but does not affect localization of U7 snRNP to the HLB cannot rescue the lethality or histone pre-mRNA processing defects resulting from an Lsm11 null mutation. The last 45 amino acids of FLASH are required for efficient localization to the HLB in Drosophila cultured cells. Removing the first 64 amino acids of FLASH has no effect on processing in vivo. Removal of 13 additional amino acids of dFLASH results in a dominant negative protein that binds Lsm11 but inhibits processing of histone pre-mRNA in vivo. Inhibition requires the Lsm11 binding site, suggesting that the mutant dFLASH protein sequesters the U7 snRNP in an inactive complex and that residues between 64 and 77 of dFLASH interact with a factor required for processing. Together, these studies demonstrate that direct interaction between dFLASH and dLsm11 is essential for histone pre-mRNA processing in vivo and for proper development and viability in flies.
Identification of mRNAs that are spliced but not exported to the cytoplasm in the absence of THOC5 in mouse embryo fibroblasts
Authors: Guria Anuja , Tran Doan Duy Hai , Ramachandran Sheetal , Koch Alexandra , El Bounkari Omar , Dutta Priyanka , Hauser Hansjörg , Tamura Teruko
Published: April 2011

The TREX (transcription/export) complex has been conserved throughout evolution from yeast to man and is required for coupled transcription elongation and nuclear export of mRNAs. The TREX complex in mammals and Drosophila is composed of the THO subcomplex (THOC1, THOC2, THOC5, THOC6, and THOC7), THOC3, UAP56, and Aly/THOC4. In human and Drosophila, various studies have shown that THO is required for the export of heat shock mRNAs, but nothing is known about other mRNAs. Our previous study using conditional THOC5 (or FMIP) knockout mice revealed that the presence of THOC5 is critical in hematopoietic cells but not for terminally differentiated cells. In this study, we describe the establishment of a mouse embryo fibroblast cell line (MEF), THOC5 flox/flox. Four days after infection of MEF THOC5 flox/flox with adenovirus carrying Cre-recombinase gene (Ad-GFP-Cre), THOC5 is down-regulated >95% at the protein level, and cell growth is strongly suppressed. Transcriptome analysis using cytoplasmic RNA isolated from cells lacking functional THOC5 reveals that only 2.9% of all genes were down-regulated more than twofold. Although we examined these genes in fibroblasts, one-fifth of all down-regulated genes (including HoxB3 and polycomb CBX2) are known to play a key role in hematopoietic development. We further identified 10 genes that are spliced but not exported to the cytoplasm in the absence of THOC5. These mRNAs were copurified with THOC5. Furthermore, Hsp70 mRNA was exported in the absence of THOC5 at 37°C, but not under heat shock condition (42°C), suggesting that THOC5 may be required for mRNA export under stress and/or upon signaling-induced conditions.
Overcoming institutional shortcomings for academic spin-off policies in Brazil
Authors: Botelho Antonio Jos Junqueira , Almeida Mariza
Published: April 2011

This exploratory study discusses the evolution of university spin-off policy in Brazil. Technology transfer and entrepreneurship infrastructures to support spin-off ventures were weak until early 2000. However, in 2004, the government passed an Innovation Law to establish a legal infrastructure and financial mechanisms to promote innovation. In its aftermath and in response to the law, a few universities sought to evolve their spin-off policy. Data collected from seven spin-offs from six universities allows an exploration of spin-off policy as a factor underpinning the growth potential of business ventures. The results discussed in this article are consistent with earlier findings for Belgium. The article concludes that in the absence of proper orientation and incentives in the unfolding policies and mechanisms underpinned by the Innovation Law, even universities that tried to take advantage of the law did not change their spin-off policies to proactively select growth-oriented spin-off ventures.
Use of virtual index for measuring efficiency of innovation systems: A cross-country study
Authors: Abbasi Farhad , Hajihoseini Hojatolah , Haukka Sandra
Published: April 2011

In this study we propose a virtual index for measuring the relative innovativeness of countries. Using a multistage virtual benchmarking process, the best and rational benchmark is extracted for inefficient ISs. Furthermore, Tobit and Ordinary Least Squares (OLS) regression models are
used to investigate the likelihood of changes in inefficiencies by investigating country-specific factors. The empirical results relating to the virtual benchmarking process suggest that the OLS regression model would better explain changes in the performance of innovation- inefficient countries.
Characterization of the Effects of Droplet Size, Air Blast Strength, and Angle on Spray Distribution and Efficacy of a Buffalo Turbine Barrier Treatment Sprayer
Authors: Bonds Jane A. S. , Mulla Cindy , Hunter Ed
Published: April 2011

A Buffalo Turbine barrier treatment sprayer was characterized physically and biologically over a range of application settings. The effects of three increasing droplet size distributions, two air blast strengths, and three blower arm angles (65°, 80°, and 90°) were measured via water sensitive papers and residual contact bioassay. The data from the water sensitive papers provided information on how machine setting influenced the deposition through the canopy. For the canopy under investigation, directing the spray straight into the canopy (90° blower angle) led to the highest deposit volumes. As droplet size distributions increased no significant change in the volume deposited was observed. The increase in air blast strength from low to high had no overall effect on the volume deposited, but the low air blast strength did show a successive loss in volume with distance into the canopy. Whereas the high air blast strength only showed a loss in volume at the furthest distance from the sprayer. Mosquito mortality did not correlate with volume deposited. Mosquito mortality was greatest with the intermediate blower arm angle (80°). The only parameter that correlated with mortality was uniformity of deposits over surfaces. It is suggested from both quantitative and qualitative observations that uniformity was the primary deposition parameter affecting control. The methods set forth in this study are simple and inexpensive our aim is to introduce them a standard methods for optimizing barrier treatment applications for vegetative barrier treatments.
Shear and Axial Load Measurement Device for Anchors in Concrete
Authors: Hoehler Matthew S. , Dowell Robert K. , Watkins Derrick A.
Published: April 2011

This paper describes the construction, calibration and experimental validation of a test apparatus to measure axial and shear forces in anchors. Accurate measurement of anchor shear force has historically proven technically challenging. The measurement device, which was developed to capture anchor load distributions on nonstructural components anchored to concrete by multiple post-installed anchors during earthquake loading, makes possible the study of previously inaccessible anchorage behavior. The device described in this paper was designed for single anchors, however, the concept can be extended to larger groups of anchors and may have application in other areas of research and testing.
Growing Big Science in a Small Country: MAX-lab and the Swedish Research Policy System
Authors: Hallonsten Olof
Published: April 2011

MAX-lab is a Swedish national synchrotron radiation facility, first established as a small-scale university project in the late 1970s and then gradually developed into a national and international user facility. This article presents a historical study of MAX-lab that illustrates the decentralized character of the Swedish science policy system and especially its lack of aggregation mechanisms for strategically important initiatives such as the establishment of large research infrastructures. The dominating university sector and the absence of strong central governance structures have made Swedish science policy pluralistic, driven from the bottom up, and decentralized. The genesis and development of MAX-lab, while remarkable when compared to other such facilities internationally, is symptomatically Swedishâ€“it has grown from the bottom up and step by step, and thereby managed to become a respected national and international user facility despite unfavorable conditions. The patchy funding model and the lack of coherent policymaking has led to underfunding and an opaque organizational structure, but MAX-lab and its users have nonetheless been of high quality. This article argues that the determination, patience, adaptivity, and, to some extent, ingenuity of the people involved in MAX-lab have compensated for systemic shortcomings and enabled the laboratory to succeed despite the unfavorable conditions.
Paul Errington, Aldo Leopold, and Wildlife Ecology: Residential Science
Authors: Kohler Robert E.
Published: April 2011

The subject of this paper is a pioneering field study of bobwhite quail by the trapper-turned-ecologist Paul Errington and the environmentalist Aldo Leopold. Their project is significant in several ways. It produced an influential environmental view of predation and contributed to Leopold's celebrated environmental ethic of “land health.” It also exemplifies a generic type of intensive or “residential” field practice, which involves knowing a research locale as intimately its human or animal residents know it, but also as generally as do cosmopolitan scientists. Finally, this essay argues that Errington's ecology and Leopold's ethic were shaped by their own residential trajectories, from the rural Midwest of their youths, through wilder environments of the Southwest and Canadian North, and back again. Place shapes field science: not just the place where research is carried on, but the places where investigators have been in their mobile careers.
Diaspora as Religious Doctrine: An “Apostle of Vietnamese Nationalism” Comes to California
Authors: Hoskins Janet
Published: April 2011

Religion and nationalism are analytically separated and often even seen as opposing forces. But Cao Dài history and theology fuses religion and nationalism, and their relationship is the defining tension in the life of Ð? V?n Lý (1910–2008). As a revolutionary, diplomat, ambassador, and religious leader, he was both a political and a religious activist who articulated a vision of “Vietnamese exceptionalism” first announced in spirit messages from the 1920s, and later developed into a diasporic theodicy to explain the fall of Sài Gòn and provide a new set of goals for exiled religious practitioners.
Transmediation in the Language Arts Classroom: Creating Contexts for Analysis and Ambiguity
Authors: McCormick Jennifer
Published: April 2011

When a language arts curriculum provided students with the opportunity to translate meaning across sign systems (that is, from poetry to dance), numerous benefits were noted. Transmediation, the translation of meaning from one sign system to another, led students to analyze compositional structures and to enhance their use of academic language across disciplines. Excerpts of teacher and student conversation around multiple artistic modalities and discussion of student written work are included in the findings presented.
The Reading Behavior of Junior Secondary Students During School Holidays in Botswana
Authors: Arua Arua E. , Arua Comfort E.
Published: April 2011

Botswana's reading culture has captured the attention of reading experts in the country for more than two decades. The survey reported in this article involved 121 junior students (aged 12 to 15 years) from two private and two government‐aided secondary schools. The results indicate that a majority of the students read during school holidays; that they engaged in both academic and leisure reading; that they read at home rather than at the library; and that their parents modeled reading behavior and bought them reading materials. Students' responses further indicate that they understood the importance of reading and read not only for leisure or academic purposes, but also to please their parents and thus promote family harmony.
“Rap Universal”: Using Multimodal Media Production to Develop ICT Literacies
Authors: Turner K.C. Nat
Published: April 2011

Through a multimodal media production literacy intervention in an extended‐day program, culturally and linguistically diverse youth developed valuable information and communication technology literacies, including

Specific how‐to skills useful in future academic, professional, social, and civic contexts

Abilities to critically interpret and produce media

Understanding of the value of skills and literacies across contexts

Instead of teaching reading and writing as universally applicable neutral skills, teachers taught students to use multimodal media production as a relevant sociocultural practice that demanded school‐based literacies.
Ask the Expert
Authors: Padak Nancy , Rasinski Timothy
Published: April 2011

Padak and Rasinski reply to questions posed via Facebook on the topic of summer reading.
FAD: Filtering, Analyzing, and Diagnosing Reading Difficulties
Authors: Mokhtari Kouider , Niederhauser Dale S. , Beschorner Elizabeth A. , Edwards Patricia A.
Published: April 2011

This basic data analysis procedure will help literacy professionals who work with struggling readers in clinical or classroom settings to identify and interpret patterns of assessment data with the goal of determining literacy strengths and needs.
Responsive Teaching Through Conversation
Authors: Dozier Cheryl , Garnett Susan , Tabatabai Simeen
Published: April 2011

Conversations are the heart of responsive teaching. By talking with struggling learners, teachers can find out about their interests in order to design effective, personalized instruction; build relationships; work through complexities in teaching and learning; and celebrate successes.
Integrating Literacy and Inquiry for English Learners
Authors: Guccione Lindsey M.
Published: April 2011

Over the course of one year in a first‐grade classroom, English learners (ELs) used several literacy practices to construct meaning from expository text. The teacher modeling, guided practice, and independent use of the five most frequent practices are explained in detail, with accompanying photographs of student work. The author describes how students integrated the literacy practices within an inquiry‐based classroom learning community.
Organizing and Evaluating Results From Multiple Reading Assessments
Authors: Rubin Jim
Published: April 2011

The challenges of understanding how reading abilities vary within the classroom can be daunting. This article offers techniques to organize a variety of assessment data to give teachers a clear picture of individual achievement, how students compare with one another, and how reliably various assessment instruments yield an accurate picture of reading ability. A class profile based on a common scale is described and used to give an overview of student reading levels.
Making Sure Our Reading “CLICKS”
Authors: Giordano Linda
Published: April 2011

The author, a veteran second‐grade teacher, has spent the past three years developing a system to help her students find appropriate books to read during independent reading time. The article describes how the CLICKS system evolved and how to introduce it to a classroom of young readers.
Hands‐On Reciprocal Teaching: A Comprehension Technique
Authors: Stricklin Kelley
Published: April 2011

Reciprocal teaching is a researched‐based technique that utilizes the comprehension strategies of predicting, clarifying, questioning, and summarizing. This article provides methods of incorporating characters, props, and visual and hands‐on tools to encourage and motivate students to learn through reciprocal teaching. Teachers are given activities to use while implementing reciprocal teaching that require very little prep time, but are highly appealing to a range of learners. Responsibilities of both the teacher and the students are addressed, as well as the importance of discussion and assessment.
USDA conservation program and practice effects on wetland ecosystem services in the Prairie Pothole Region
Authors: Gleason R. A. , Euliss N. H. , Tangen B. A. , Laubhan M. K. , Browne B. A.
Published: April 2011

Implementation of the U.S. Department of Agriculture (USDA) Conservation Reserve Program (CRP) and Wetlands Reserve Program (WRP) has resulted in the restoration of >2 million ha of wetland and grassland habitats in the Prairie Pothole Region (PPR). Restoration of habitats through these programs provides diverse ecosystem services to society, but few investigators have evaluated the environmental benefits achieved by these programs. We describe changes in wetland processes, functions, and ecosystem services that occur when wetlands and adjacent uplands on agricultural lands are restored through Farm Bill conservation programs. At the scale of wetland catchments, projects have had positive impacts on water storage, reduction in sedimentation and nutrient loading, plant biodiversity, carbon sequestration, and wildlife habitat. However, lack of information on the geographic location of restored catchments relative to landscape‐level factors (e.g., watershed, proximity to rivers and lakes) limits interpretation of ecosystem services that operate at multiple scales such as floodwater retention, water quality improvement, and wildlife habitat suitability. Considerable opportunity exists for the USDA to incorporate important landscape factors to better target conservation practices and programs to optimize diverse ecosystem services. Restoration of hydrologic processes within wetlands (e.g., hydroperiod, water level dynamics) also requires a better understanding of the influence of conservation cover composition and structure, and management practices that occur in uplands surrounding wetlands. Although conservation programs have enhanced delivery of ecosystem services in the PPR, the use of programs to provide long‐term critical ecosystem services is uncertain because when contracts (especially CRP) expire, economic incentives may favor conversion of land to crop production, rather than reenrollment. As demands for agricultural products (food, fiber, biofuel) increase, Farm Bill conservation programs will become increasingly important to ensure provisioning of ecosystem services to society, especially in agriculturally dominated landscapes. Thus, continued development and support for conservation programs legislated through the Farm Bill will require a more comprehensive understanding of wetland ecological services to better evaluate program achievements relative to conservation goals.
Agricultural conservation practices increase wetland ecosystem services in the Glaciated Interior Plains
Authors: Fennessy Siobhan , Craft Christopher
Published: April 2011

The Glaciated Interior Plains historically supported a broad variety of wetland types, but wetland losses, primarily due to agricultural drainage, range from 50% to 90% of presettlement area. Wholesale land use change has created one of the most productive agricultural regions on earth, but wetland conversion has also led to the loss of the ecosystem services they provide, particularly water quality improvement, flood de‐synchronization, carbon sequestration, and support of wetland‐dependent species (biodiversity). Nearly three‐quarters of the Glaciated Interior Plains fall within the Mississippi River drainage basin, where the combination of extensive tile drainage and fertilizer use has produced watersheds that contribute some of the highest nitrogen yields per acre to the Mississippi River. Wetland conservation practices implemented under Farm Bill conservation programs have established or involved management of nearly 110 000 ha of wetlands, riparian zones, and associated ecosystem services over the period 2000–2007. We estimated the cumulative ability of these conservation practices to retain sediment, nitrogen, and phosphorus in Upper Mississippi River Basin watersheds. Estimated retention amounts to 1.0%, 1.5%, and 0.8% of the total N, sediment, and P, respectively, reaching the Gulf of Mexico each year. If nutrient reduction is estimated based on the quantity of nutrients exported from the Glaciated Interior Plains region only, the numbers increase to 6.8% of N, 4.9% of P, and 11.5% of sediment generated in the region annually. On a watershed basis, the correlation between the area of wetland conservation practices implemented and per‐hectare nutrient yield was 0.81, suggesting that, for water quality improvement, conservation practices are successfully targeting watersheds that are among the most degraded. The provision of other ecosystem services such as C sequestration and biodiversity is less well studied. At best, implementation of wetland and riparian conservation practices in agricultural landscapes results in improved environmental quality and human health, and strengthens the rationale for expanding conservation practices and programs on agricultural lands.
Wetland ecosystem services and coupled socioeconomic benefits through conservation practices in the Appalachian Region
Authors: Wardrop Denice H. , Glasmeier Amy K. , Peterson-Smith Jessica , Eckles Diane , Ingram Hannah , Brooks R. P.
Published: April 2011

The adjacency of agriculture and water resources is, perhaps, nowhere more prevalent than it is in Appalachia, USA. Agricultural activities have documented impacts on the ability of wetlands and other aquatic systems to provide ecosystem services; in order to diminish and/or mitigate these impacts, the Natural Resources Conservation Service (NRCS) carries out resource assessment and place‐based conservation planning on agricultural lands. We contend that a comprehensive assessment of the effectiveness of restoration of wetland ecosystem services within an agricultural landscape should include both ecological and socioeconomic metrics, as follows: (1) the amount and type of ecosystem services most at risk, and restored by NRCS conservation program investment; (2) a spatially based assessment of the replacement/addition of ecosystem services from both an ecological and a socioeconomic perspective; and (3) consideration of ecosystem service replacement in context with adjacent land use and population dynamics as a preliminary consideration of differential value. We utilize the Appalachian Region as a demonstration of these necessary elements in assessing the effectiveness of the conservation/restoration investments made over the period of 2000–2006. We identified a total of 1.7 million ha (4.2 million acres) of wetland polygons, with ∼17% located in an agricultural setting. We developed a classification crosswalk and utilize Hydrogeomorphic Functional Assessment models to demonstrate the relative investment of the 522 583 ha (1 291 330 acres) of wetland‐relevant practices across a suite of ecosystem services, with a heavy investment in the nutrient‐cycling functions. We examined conservation program implementation in a classification scheme that allocates counties into Urban, Rural, Mixed‐Urban, and Mixed‐Rural categories based on population characteristics, and assessed the relationship between wetland conservation program application and population dynamics. We found Mixed‐Urban and Mixed‐Rural counties to have the most wetland in agricultural settings that could be targeted for conservation measures. However, conservation practices have been applied mostly in the Mixed‐Rural and Rural counties, indicating a potential overinvestment in the latter. When total acres of conservation measures are examined over a gradient of both urban and total population growth rates, we do not see a concomitant increase in the application of wetland conservation practices, and program investment appears relatively random.
Labile, dissolved and particulate PAHs and trace metals in wastewater: passive sampling, occurrence, partitioning in treatment plants
Authors: Gourlay-Francé C. , Bressy A. , Uher E. , Lorgeoux C.
Published: April 2011

The occurrence and the partitioning of polycyclic aromatic hydrocarbons (PAHs) and seven metals (Al, Cd, Cr, Cu, Ni, Pb and Zn) were investigated in activated sludge wastewater treatment plants by means of passive and active sampling. Concentrations total dissolved and particulate contaminants were determined in wastewater at several points across the treatment system by means of grab sampling. Truly dissolved PAHs were sampled by means of semipermeable membrane devices. Labile (inorganic and weakly complexed) dissolved metals were also sampled using the diffusive gradient in thin film technique. This study confirms the robustness and the validity of these two passive sampling techniques in wastewater. All contaminant concentrations decreased in wastewater along the treatment, although dissolved and labile concentrations sometimes increased for substances with less affinity with organic matter. Solid–liquid and dissolved organic matter/water partitioning constants were estimated. The high variability of both partitioning constants for a simple substance and the poor relation between KD and KOW shows that the binding capacities of particles and organic matter are not uniform within the treatment and that other process than equilibrium sorption affect contaminant repartition and fate in wastewater.
Adsorption and removal at low atrazine concentration in an MBR pilot plant
Authors: Buttiglieri G. , Migliorisi L. , Malpei F.
Published: April 2011

Atrazine is a persistent organic pollutant and it has been widely used in agriculture and forestry in the world for more than fifty years. Atrazine shows ecotoxicity effects in aquatic ecosystems even at very low level concentrations with endocrine disruptor activity. Few studies were carried out on atrazine removal performances in drinking and waste-water by biological treatments, especially in membrane bio-reactors (MBRs). MBR technology might be more efficient than the conventional one in the removal of micro-pollutants. The fate of atrazine in wastewater treatment plants and its influence on the biomass activity was evaluated in this study. The experimental work was divided in three different phases: inhibition studies on different types of biomass (by means of microcalorimetry); adsorption studies on different sludges (conventional activated sludge (CAS) – and MBR) calculating adsorption isotherms and, finally, atrazine removal in an MBR pilot plant (simulating a treatment of atrazine and nitrate contaminated groundwater). The absence of significant inhibition was observed; higher atrazine adsorption on MBR sludge was detected for lower atrazine concentration (<50 µg L−1); the removal efficiency in the MBR pilot plant was lower than 25% but higher than the theoretical one (based on adsorption isotherms).
Arsenic mass balance in a paper mill and impact of the arsenic release from the WWTP effluent on the Moselle River
Authors: Michon C. , Pons M.-N. , Bauda P. , Poirot H. , Potier O.
Published: April 2011

Rivers used for drinking water production might be subject to anthropogenic pollution discharge upstream of the intake point. This problem was investigated in the case of the Moselle River, used for water production in Nancy (350,000 inhabitants) and which might be impacted by industrial activities 60 km upstream. The arsenic flux of a pulp and paper mill discharging in the Moselle River at this location has been more specifically investigated. The main sources of arsenic in that mill seemed to be the recovered papers and the gravel pit water used as feed water. The arsenic input related to wood and bark was limited. The main arsenic outputs from the plant were the paper produced on site and the deinking sludge. The arsenic concentration in the effluent of the wastewater treatment plant (WWTP) was not correlated to the one in the gravel pit water, but may depend on the operating conditions of the WWTP or the changes in processes of the mill. The impact of this anthropogenic source of arsenic on the Moselle River was slightly larger in summer, when the flowrate was lower. Globally the impact of the paper mill on the Moselle River water quality was limited in terms of arsenic.
Substance flow analysis as a tool for urban water management
Authors: Chèvre N. , Guignard C. , Rossi L. , Pfeifer H.-R. , Bader H.-P. , Scheidegger R.
Published: April 2011

Human activity results in the production of a wide range of pollutants that can enter the water cycle through stormwater or wastewater. Among others, heavy metals are still detected in high concentrations around urban areas and their impact on aquatic organisms is of major concern. In this study, we propose to use a substance flow analysis as a tool for heavy metals management in urban areas. We illustrate the approach with the case of copper in Lausanne, Switzerland. The results show that around 1,500 kg of copper enter the aquatic compartment yearly. This amount contributes to sediment enrichment, which may pose a long-term risk for benthic organisms. The major sources of copper in receiving surface water are roofs and catenaries of trolleybuses. They represent 75% of the total input of copper into the urban water system. Actions to reduce copper pollution should therefore focus on these sources. Substance flow analysis also highlights that copper enters surface water mainly during rain events, i.e., without passing through any treatment procedure. A reduction in pollution could also be achieved by improving stormwater management. In conclusion, the study showed that substance flow analysis is a very effective tool for sustainable urban water management.
Evaluation of model parameters for simulating TiO2 coated UV reactors
Authors: Duran J. E. , Taghipour F. , Mohseni M.
Published: April 2011

A CFD-based model for simulating TiO2 coated photocatalytic reactors used in drinking water treatment applications was preliminarily evaluated. The model includes aspects of hydrodynamics, mass transfer, UV-radiation field, and surface chemical reactions. Appropriate models for each of the associated physicochemical phenomena were experimentally or analytically examined. Once defined and evaluated, the individual models were integrated into a CFD-based model for simulating photocatalytic reactor performance, which was experimentally evaluated.
Real-time monitoring of membrane bioreactors with 2D-fluorescence data and statistically based models
Authors: Galinha C. F. , Carvalho G. , Portugal C. A. M. , Guglielmi G. , Oliveira R. , Crespo J. G. , Reis M. A. M.
Published: April 2011

The application of membrane bioreactors (MBR) for wastewater treatment is growing worldwide due to their compactness and high effluent quality. However, membrane fouling, mostly associated to biological products, can reduce MBR performance. Therefore, it is important to monitor MBRs as close to real-time as possible to accelerate control actions for maximal biological and membrane performance. 2D-fluorescence spectroscopy is a promising on-line tool to simultaneously monitor wastewater treatment efficiency and the formation of potential biological fouling agents. In this study, 2D-fluorescence data obtained from the wastewater and the permeate of a MBR was successfully modelled using projection to latent structures (PLS) to monitor variations in the influent and effluent total chemical oxygen demand (COD). Analysis of the results also indicated that humic acids and proteins highly contributed to the measured COD in both streams. Nevertheless, this approach was not valid for other performance parameters of the MBR system (such as influent and effluent ammonia and phosphorus), which is usually characterised through a high number of analytical and operating parameters. Principal component analysis (PCA) was thus used to find possible correlations between these parameters, in an attempt to reduce the analytical effort required for full MBR characterisation and to reduce the time frame necessary to obtain monitoring results. The 3 first principal components, capturing 57% of the variance, indicated and confirmed expected relationships between the assessed parameters. However, this approach alone could not provide robust enough correlations to enable the elimination of parameters for process description (PCA loadings ≤ 0.5). Nevertheless, it is possible that the information captured by 2D-fluorescence spectroscopy could replace some of the analytical and operating parameters, since this technique was able to successfully describe influent and effluent total COD. It is thus proposed that combined modelling of 2D-fluorescence data and selected performance/operating parameters should be further explored for efficient MBR monitoring aiming at rapid process control.
Biochemical acidogenic potential in domestic wastewaters: effect of sampling and storage to characterize daily average composite samples
Authors: Choubert J. -M. , Granger D. , Bourdon C. , Héduit A.
Published: April 2011

To estimate the expectable enhanced biological phosphorus removal value of a wastewater, the concentration of volatile fatty acids (VFAs) and the biochemical acidogenic potential (BAP) are generally determined on grab samples of wastewater, as these variables are prone to rapid change after sampling. However, such sampling technique do not take into account the variations of these parameters during the day. This work has evaluated the changes of VFAs and BAP occurring during sampling and storage in an automatic sampler over 24 h. The consequences of waterfall oxygen input during sampling, and changes during storage (fermentation and sulfatereducing process) were studied. The results for two wastewaters showed that the sampling technique used for daily flow proportional composite samples provided a correct estimation of VFAs, and underestimated BAP by up to 25%. For hourly-average composite samples of wastewaters, significant modifications of the concentrations of these two parameters were recorded around the daily average values.
Integrated membrane systems incorporating coagulation, activated carbon and ultrafiltration for the removal of toxic cyanobacterial metabolites from Anabaena circinalis
Authors: Dixon M. B. , Richard Y. , Ho L. , Chow C. W. K. , O'Neill B. K. , Newcombe G.
Published: April 2011

The use of integrated membrane systems (a train of treatment processes incorporating one or more membranes) is increasing globally as the technology is very effective for the production of high quality drinking water. In this investigation a laboratory scale integrated membrane system (IMS) featuring coagulation, powdered activated carbon (PAC) and ultrafiltration (UF) was investigated for the removal of an Australian strain of the cyanobacteria Anabaena circinalis and the cyanotoxin it produced. Three coagulants were compared, aluminium chlorohydrate (ACH), aluminium sulphate (alum) and an engineered aluminium coagulant referred to as high performance aluminium chlorohydrate (HPAC). PAC (Acticarb PS1000) was tested to determine adsorption of extracellular saxitoxin. Removal of A. circinalis cells was 100% by UF alone and the removal of cells prior to the membrane by coagulation reduced fouling attributed to algogenic organic material. Alum was the least efficient coagulant for removal of cells while ACH and HPAC were similar. Saxitoxin removal reached a maximum of 80% using ACH and PAC. The UF-IMS was challenged using a natural bloom of A. circinalis that occurred in the Myponga Reservoir in South Australia.
Analysis of the bacterial community changes in soil for septic tank effluent treatment in response to bio-clogging
Authors: Nie J. Y. , Zhu N. W. , Zhao K. , Wu L. , Hu Y. H.
Published: April 2011

Soil columns were set up to survey the bacterial community in the soil for septic tank effluent treatment. When bio-clogging occurred in the soil columns, the effluent from the columns was in poorer quality. To evaluate changes of the soil bacterial community in response to bio-clogging, the bacterial community was characterized by DNA gene sequences from soil samples after polymerase chain reaction coupled with denaturing gradient gel electrophoresis process. Correspondence analysis showed that Proteobacteria related bacteria were the main bacteria within the soil when treating septic tank effluent. However, Betaproteobacteria related bacteria were the dominant microorganisms in the normal soil, whereas Alphaproteobacteria related bacteria were more abundant in the clogged soil. This study provided insight into changes of the soil bacterial community in response to bio-clogging. The results can supply some useful information for the design and management of soil infiltration systems.