bluuebunny/crossref_metadata_2025 huggingface dataset:
Killing Memory
Authors: Bednar Robert M.
Published: December 2013

This article explores affect and memory at roadside car crash memorials within the context of what Achille Mbembe calls “necropolitics”: the performance of power to determine who legitimately can kill both persons and the memory of persons. By analyzing the ritualized performance of compulsory compassion in news media stories about the actual or threatened removal of roadside memorials, I argue that there is an economy of power circulating in the practice of roadside memorialization, where some subjects are deemed legitimately memorable and some are not, where some subjects are legitimately allowed to memorialize their losses in public landscapes and others are not, and where anonymous drivers who drive by are supposed to feel a certain way about it all. Such a complex constellation of territorialized affect has significant consequences for understanding the politics of affect and memory in public landscapes.
Tailoring the recovery force in magnetic shape-memory nanocomposites
Authors: Behl M. , Razzaq M.Y. , Lendlein A.
Published: December 2013

Composites from magnetic nanoparticles in a shape-memory polymer (SMP) matrix allow a remote actuation of the shape-memory effect by exposure to alternating magnetic fields. At the same time the incorporation of MNP may affect the thermal properties and the structural functions of the SMP.

Here, we explored the adjustability of the recovery force as an important structural function in magnetic shape-memory nanocomposites (mSMC) by variation of the programing temperature (Tprog) and nanoparticle weight content. The nanocomposites were prepared by coextrusion of silica coated magnetite nanoparticles (mNP) with an amorphous polyether urethane (PEU) matrix. In tensile tests in which Tprog was varied between 25 and 70 °C and the particle content from 0 to 10 wt% it was found that the Young’s moduli (E) decreased with temperature and particle content. Cyclic, thermomechanical experiments with a recovery module under strain-control conditions were performed to monitor the effect of mNP and Tprog on the recovery force of the composites. During the strain-control recovery the maximum stress (σm,r) at a characteristic temperature (Tσ,max) was recorded. By increasing the mNP content from 0 to 10 wt% in composites, σm,r of 1.9 MPa was decreased to 1.25 MPa at a Tprog = 25 °C. A similar decrease in σm,r for nanocomposites with different mNP content could be observed when Tprog was increased from 25 °C to 70 °C. It can be concluded that the lower the deformation temperature and the particle content the higher is the recovery force.
Tailoring of Mechanical Properties of Diisocyanate Crosslinked Gelatin-Based Hydrogels
Authors: Neffe Axel T. , Gebauer Tim , Lendlein Andreas
Published: December 2013

Polymer network formation is an important tool for tailoring mechanical properties of polymeric materials. One option to synthesize a network is the addition of bivalent crosslinkers reacting with functional groups present in a polymer. In case of polymer network syntheses based on biopolymers, performing such a crosslinking reaction in water is sometimes necessary in view of the solubility of the biopolymer, such as gelatin, and can be beneficial to avoid potential contamination of the formed material with organic solvents in view of applications in biomedicine. In the case of applying diisocyanates for the crosslinking in water, it is necessary to show that the low molecular weight bifunctional crosslinker has fully reacted, while tailoring of the mechanical properties of the resulting hydrogels is possible despite the complex reaction mechanism. Here, the formation of gelatin-based hydrogel networks with the diisocyanates 2,4-toluene diisocyanate, 1,4-butane diisocyanate, and isophorone diisocyanate is presented. It is shown that extensive washing of materials is required to ensure full conversion of the diisocyanates. The use of different diisocyanates gives hydrogels covering a large range of Young’s moduli (12-450 kPa). The elongations at break (up to 83%) as well as the maximum tensile strengths (up to 410 kPa) of the hydrogels described here are much higher than for lysine diisocyanate ethyl ester crosslinked gelatin reported before. Rheological investigations suggest that the network formation in some cases is due to physical interactions and entanglements rather than covalent crosslink formation.
Societal Changes and New Conditions for the Management of Large Construction Projects
Authors: Szentes Henrik , Eriksson Per Erik
Published: December 2013

The construction industry is often described as mature, conservative and resistant to change in research studies,
governmental reports as well as in media. Both scholars and policy makers thereby find it critical to encourage innovation,
development, and change within the construction industry. This study takes on a different perspective by investigating
changes that have actually taken place. The aim is to increase the understanding of both backgrounds of changes which
occurred, as well as how the changes have entailed new conditions for the management of large construction projects in
Sweden. People working as clients’ project manager, contractors’ project manager or design manager were interviewed to
obtain their perceived views on changes influencing the execution of large construction projects. Substantial changes have
taken place creating new conditions for the management of large construction projects and a better understanding of these
new conditions is important when planning for new projects. Changes within the field are often reactions to societal
changes, and thus often implemented in an uncoordinated way creating sub-optimization and problems for the personnel.
It seems as if the reputation of the construction industry being conservative has become an institution it-self amongst
many professionals within the industry, potentially creating a self-fulfilling prophecy.
Frictions in Forest Pedagogies: Common Worlds in Settler Colonial Spaces
Authors: Pacini-Ketchabaw Veronica
Published: December 2013

Bringing frictions to children's visits to a forest in British Columbia (BC) as possibilities for ‘common worlds pedagogies’, this article proceeds by troubling forest colonialisms, untangling forest histories and trajectories, attending to more-than-human elements of the forest, and inhabiting the forest with children. The article engages with the kinds of questions, wonderings, uncertainties, and possibilities that emerge when forest pedagogies become part of common worlds – in other words, when forests are understood as entangled natureculture spaces in which children, early childhood educators, and the forests themselves shape each other.
The Nature/Cultures of Children's Place Learning Maps
Authors: Somerville Margaret
Published: December 2013

This article explores the question of how we can teach and learn beyond the nature/culture binary for a more sustainable world. It is based on a study of place-based learning for sustainability in a primary school in Latrobe Valley, Gippsland, Australia, the site of brown coal-fired energy production. The focus of the article is on primary school students' wonderings and learning maps produced in response to their educational activities in a local wetlands. The learning maps are analysed using the lens of ‘thinking through Country’ which offers a contemporary translation of an Aboriginal onto-epistemology in which nature and culture are conjoined (nature/culture). Using this contemporary Aboriginal onto-epistemological framework as a lens for analysis focuses the reading of children's place learning artefacts on the possibilities of moving beyond nature/culture binaries in place-based learning. The reading identifies the ways that children's place learning can enter representation and language without losing the materiality of embodied place connection. In this way place learning becomes available as nature/culture for pedagogical work and opens the possibility of new ways to teach and learn for planetary sustainability.
Synthesis and characterization of a silylated Brazilian clay mineral surface
Authors: Silva Márcia , Gomes Saloana , Fonseca Maria , Sousa Kaline , Espínola José , Silva Filho Edson
Published: December 2013

Clay mineral containing kaolinite, illite and montmorillonite was organofunctionalized with silylating agents: (3-aminopropyl)triethoxysilane, 3-[2-(2-aminoethylamino)ethylamino]propyl-trimethoxysilane and (3-mercaptopropyl)trimethoxy-silane, to yield three hybrids labelled Clay1, Clay2 and Clay3, respectively. These solids were characterized using elemental analysis, thermogravimetry, X-ray diffractometry, infrared spectroscopy, scanning electron micrograph, and 29Si and 27Al solid state NMR. Immobilized quantities of the organic groups were 0.66 mmol g−1, 0.48 mmol g−1 and 0.88 mmol g−1 for Clayx (x = 1–3), respectively. X-ray diffraction patterns confirmed the immobilization of silanes onto the surface without changes in the textural properties of the clay mineral as noted from the SEM images. Spectroscopic measurements were in agreement with the covalent bonding between the silanes and the hydroxyl groups deposited on the surface. The new hybrids were utilized as adsorbents of cobalt in aqueous solution, with retention values of 0.78 mmol g−1, 1.1 mmol g−1 and 0.70 mmol g−1 for Clayx (x = 1–3), respectively.
Health Professionals’ Alcohol-Related Professional Practices and the Relationship between Their Personal Alcohol Attitudes and Behavior and Professional Practices: A Systematic Review
Authors: Bakhshi Savita , While Alison
Published: December 2013

Health professionals’ personal health behaviors have been found to be associated with their practices with patients in areas such as smoking, physical activity and weight management, but little is known in relation to alcohol use. This review has two related strands and aims to: (1) examine health professionals’ alcohol-related health promotion practices; and (2) explore the relationship between health professionals’ personal alcohol attitudes and behaviors, and their professional alcohol-related health promotion practices. A comprehensive literature search of the Cochrane Library, MEDLINE, EMBASE, PsycINFO, CINAHL, British Nursing Index, Web of Science, Scopus and Science Direct (2007–2013) identified 26 studies that met the inclusion criteria for Strand 1, out of which six were analyzed for Strand 2. The findings indicate that health professionals use a range of methods to aid patients who are high-risk alcohol users. Positive associations were reported between health professionals’ alcohol-related health promotion activities and their personal attitudes towards alcohol (n = 2), and their personal alcohol use (n = 2). The findings have some important implications for professional education. Future research should focus on conducting well-designed studies with larger samples to enable us to draw firm conclusions and develop the evidence base.
Improving Health Outcomes of Children through Effective Parenting: Model and Methods
Authors: Okafor Martha , Sarpong Daniel , Ferguson Aneeqah , Satcher David
Published: December 2013

This article reports on the design, development, testing and presentation of preliminary evidence of a translational, culturally relevant parenting education model, titled Smart and Secured Children (SSC). SSC, a quality parenting curriculum, prepares disparate African American parents as leaders for transforming their parenting behaviors and leading their peers and community in changing existing parenting culture. The article recommends expanded utility of identified promising processes, approaches and practices to engage African American parents to lead in addressing health inequity conditions in their families and communities. It adds to the growing scientific literature on the association between parent–child relationship quality and a wide variety of children physical, emotional and social outcomes. SSC applied principles of developmental theories; community based participatory research (CBPR), and iterative Delphi method between the community stakeholders, parents and researchers. The delivery approach of SSC was revamped from professional-led to parent-led content presentation and delivery methods using a conversational learning approach, referred to as ‘conversepedia’. Parents’ leadership development training and delivery of this curriculum in social supportive groups improved their mental wellbeing, parenting capacity and leadership skills. Parents do matter and can choose positive influence in their lives and are capable of reversing negative peer influence.
Methods for Distributed Compressed Sensing
Authors: Sundman Dennis , Chatterjee Saikat , Skoglund Mikael
Published: December 2013

Compressed sensing is a thriving research field covering a class of problems where a large sparse signal is reconstructed from a few random measurements. In the presence of several sensor nodes measuring correlated sparse signals, improvements in terms of recovery quality or the requirement for a fewer number of local measurements can be expected if the nodes cooperate. In this paper, we provide an overview of the current literature regarding distributed compressed sensing; in particular, we discuss aspects of network topologies, signal models and recovery algorithms.
Molecular Docking Characterization of a Four-Domain Segment of Human Fibronectin Encompassing the RGD Loop with Hydroxyapatite
Authors: Guo Tailin , Kang Wenyuan , Xiao Dongqin , Duan Rongquan , Zhi Wei , Weng Jie
Published: December 2013

Fibronectin adsorption on biomaterial surfaces plays a key role in the biocompatibility of biomedical implants. In the current study, the adsorption behavior of the 7–10th type III modules of fibronectin (FN-III7–10) in the presence of hydroxyapatite (HAP) was systematically investigated by using molecular docking approach. It was revealed that the FN-III10 is the most important module among FN-III7–10 in promoting fibronectin binding to HAP by optimizing the interaction energy; the arginine residues were observed to directly interact with the hydroxyl group of HAP through electrostatic forces and hydrogen bonding. Moreover, it was found that the HAP-binding sites on FN-III10 are mainly located at the RGD loop region, which does not affect the interaction between the fibronectin protein and its cognate receptors on the cell surface.
Cohesive Fracture Study of a Bonded Coarse Silica Sand Aggregate Bond Interface Subjected to Mixed-Mode Bending Conditions
Authors: Chen Donna , El-Hacha Raafat
Published: December 2013

One of the primary objectives in the design of composite structures is the prevention of premature bond failure. Therefore, the characterization of cohesive behavior is an important field of study in structural engineering. Using fracture mechanics principles, the cohesive behavior of an epoxy bonded coarse silica sand aggregate bond interface is studied in this paper, with a focus on finding a general analytical form of idealizing its behavior when used in a specimen possessing asymmetric and inhomogeneous qualities. Two series of small-scale specimens were experimentally tested under mixed-mode bending (MMB) conditions, where it was found that there was negligible influence exerted on the fracture energy of the interface due to changes in the mixed-mode ratio or initial crack length. Using finite element analysis (FEA) methods, an appropriate bilinear traction-separation model was developed to both validate as well as obtain a set of consistent parameters applicable to all tested specimens. Comparison of the Global Method and the Local Method, used to obtain partitioned Mode I and Mode II fracture energy values from MMB specimens, were made, with the conclusion that both methods are adequate in the calculation of the total fracture energy though the Local Method should be used to obtain accurate partitioned Mode I and Mode II fracture energy values. Idealization of the bond interface using the cohesive parameters derived can be accurately achieved by the use of both contact interactions and cohesive elements in two-dimensional and three-dimensional FE models, though the results obtained using contact interactions would be expected to exhibit greater global stiffness.
Efficiency Enhancement of a Cantilever-Based Vibration Energy Harvester
Authors: Kubba Ali , Jiang Kyle
Published: December 2013

Extracting energy from ambient vibration to power wireless sensor nodes has been an attractive area of research, particularly in the automotive monitoring field. This article reports the design, analysis and testing of a vibration energy harvesting device based on a miniature asymmetric air-spaced cantilever. The developed design offers high power density, and delivers electric power that is sufficient to support most wireless sensor nodes for structural health monitoring (SHM) applications. The optimized design underwent three evolutionary steps, starting from a simple cantilever design, going through an air-spaced cantilever, and ending up with an optimized air-spaced geometry with boosted power density level. Finite Element Analysis (FEA) was used as an initial tool to compare the three geometries’ stiffness (K), output open-circuit voltage (Vave), and average normal strain in the piezoelectric transducer (εave) that directly affect its output voltage. Experimental tests were also carried out in order to examine the energy harvesting level in each of the three designs. The experimental results show how to boost the power output level in a thin air-spaced cantilever beam for energy within the same space envelope. The developed thin air-spaced cantilever (8.37 cm3), has a maximum power output of 2.05 mW (H = 29.29 μJ/cycle).
Contours of a Resilient Global Future
Authors: Gerst Michael , Raskin Paul , Rockström Johan
Published: December 2013

Humanity confronts a daunting double challenge in the 21st century: meeting widely-held aspirations for equitable human development while preserving the bio-physical integrity of Earth systems. Extant scientific attempts to quantify futures that address these sustainability challenges are often not comprehensive across environmental and social drivers of global change, or rely on quantification methods that largely exclude deep social, cultural, economic, and technological shifts, leading to a constrained set of possibilities. In search of a broader set of trajectories, we combine three previously separate streams of inquiry: scenario analysis, planetary boundaries, and targets for human development. Our analysis indicates there are plausible, diverse scenarios that remain within Earth’s safe bio-physical operating space and achieve a variety of development targets. However, dramatic social and technological changes are required to avert the social-ecological risks of a conventional development trajectory. One identified narrative, which is predominant in the scenario literature, envisions marginal changes to the social and cultural drivers underlying conventional growth trajectories. As a result, it requires unprecedented levels of international cooperation, alignment of powerful conflicting interests, and political willpower to bend technological change in a sustainable direction. We posit that a more viable and robust scenario might lie in the coupling of transformative social-cultural and technological changes, which set the necessary conditions for a transition to a resilient global future. While clearly a first step, our analysis points to the need for more in-depth exploration of the mechanisms and determinant forces for such unconventional futures.
Preparation of NiS/ZnIn2S4 as a superior photocatalyst for hydrogen evolution under visible light irradiation
Authors: Wei Liang , Chen Yongjuan , Zhao Jialin , Li Zhaohui
Published: December 2013

In this study, NiS/ZnIn2S4 nanocomposites were successfully prepared via a facile two-step hydrothermal process. The as-prepared samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM). Their photocatalytic performance for hydrogen evolution under visible light irradiation was also investigated. It was found that the photocatalytic hydrogen evolution activity over hexagonal ZnIn2S4 can be significantly increased by loading NiS as a co-catalyst. The formation of a good junction between ZnIn2S4 and NiS via the two step hydrothermal processes is beneficial for the directional migration of the photo-excited electrons from ZnIn2S4 to NiS. The highest photocatalytic hydrogen evolution rate (104.7 μmol/h), which is even higher than that over Pt/ZnIn2S4 nanocomposite (77.8 μmol/h), was observed over an optimum NiS loading amount of 0.5 wt %. This work demonstrates a high potential of the developing of environmental friendly, cheap noble-metal-free co-catalyst for semiconductor-based photocatalytic hydrogen evolution.
Lightweight concrete blocks with EVA recycled aggregate: a contribution to the thermal efficiency of building external walls
Authors: De Melo A. B. , Silva E. P.
Published: December 2013

The regions with lots of shoe production suffer environmental impacts from waste generation during manufacturing of insoles and outsoles. Research conducted in Brazil has demonstrated the technical feasibility to recycle these wastes, especially Ethylene Vinyl Acetate (EVA), as lightweight aggregate, in the production of non-structural cement blocks. This article presents an evaluation of thermal performance with measurements of temperature variation in mini walls (1 m2) built with different materials, including various kinds of EVA block and ceramic bricks. Tests have shown efficient thermal performance for masonry blocks with EVA. These results and supplementary estimates contribute to add value to the EVA block, considering that there are good expectations that the component, with the new geometry proposed, can contribute to the energy efficiency of buildings, highlighting its suitability to most Brazilian bioclimatic regions.
Risks associated with tandem release of large and small ladybirds (Coleoptera: Coccinellidae) in heterospecific aphidophagous guilds
Authors: Omkar  , Mishra Geetanjali , Kumar Bhupendra , Singh Neha , Pandey Garima
Published: December 2013

Multiple interactions occurring within aphidophagous guilds determine their final predation outcomes, i.e., antagonistic, additive, or synergistic. Based on these predatory outcomes, the suitability of guilds in suppressing aphid pests is determined. The present study assesses the efficacy of 11 guilds, formed from both larval and adult stages of four locally abundant aphidophagous coccinellids (Coleoptera: Coccinellidae), while exploiting the pea aphid, Acyrthosiphon pisum Harris (Hemiptera: Aphididae). The observed antagonistic effects within these guilds are resultants of enhanced predator–predator interactions due to the size and diversity of guild predators. Smaller ladybird predators maintained their usual body mass, probably by increasing their conversion efficiencies to compensate for their reduced prey consumption. However, larger ladybirds reported loss in their body mass, owing to their higher energy needs. The overall guild conversion efficiencies and growth rates were reduced. Among the experimental guilds, the observed prey mortalities were relatively higher in two-predator guilds, and within these two-predator combinations, the higher prey mortalities were recorded in those guilds where Coccinella septempunctata was one of the predators.
Effect of arginine supplementation of broiler breeder hens on progeny performance
Authors: Fernandes Jovanir Inês Müller , Murakami Alice Eiko , de Souza Luciana Maria Gomes , Ospina-Rojas Iván Camilo , Rossi Robson Marcelo
Published: December 2013

Fernandes, J. I. M., Murakami, A. E., Gomes de Souza, L. M., Ospina-Rojas, I. C. and Rossi, R. M. 2014. Effect of arginine supplementation of broiler breeder hens on progeny performance. Can. J. Anim. Sci. 94: 313–321. Two experiments were conducted to determine the effects of arginine (Arg) supplementation of broiler breeder hens on the performance, carcass yield, and bone measurements of their progeny. In both experiments, the maternal diet was supplemented with five levels of digestible Arg (0.94, 1.09, 1.24, 1.39 and 1.54%). In exp. 1, a total progeny of 1050 chicks were housed in pens according to maternal diet and fed a typical diet without L-Arg supplementation. In exp. 2, a total progeny of 960 chicks were kept in pens according to maternal diet and fed diets containing supplemental L-Arg from 1.30 to 1.90% in the starter phase and from 1.15 to 1.75% in the grower phase. The data obtained in both experiments were deployed in orthogonal polynomials to allow for an analysis of variance and a regression analysis. In the starter phase, there was a quadratic effect (P<0.05) of Arg level in the maternal diet on the feed:gain ratio of the non-supplemented progeny. In the Arg-supplemented progeny, there was a quadratic effect (P<0.05) of Arg level on the feed intake and feed:gain ratio and a linear increase (P<0.05) in body weight gain, and carcass and breast yields (P<0.05). Femur length, tibia diameter, and the Seedor index of both bones increased linearly (P<0.05) in broilers fed the Arg-supplemented diet. Arg supplementation in the broiler breeder hen diets had little positive effect on the non-supplemented progeny; thus, Arg supplementation in the progeny diet is necessary to optimize performance, carcass yield, and bone quality of these hens’ progeny.
Estimation of genetic parameters of fertility traits in Chinese Holstein cattle
Authors: Guo Gang , Guo Xiangyu , Wang Yachun , Zhang Xu , Zhang Shengli , Li Xizhi , Liu Lin , Shi Wanhai , Usman Tahir , Wang Xinyu , Du Lixin , Zhang Qin
Published: December 2013

Guo, G., Guo, X., Wang, Y., Zhang, X., Zhang, S., Li, X., Liu, L., Shi, W., Usman, T., Wang, X., Du, L. and Zhang, Q. 2014. Estimation of genetic parameters of fertility traits in Chinese Holstein cattle. Can. J. Anim. Sci. 94: 281–285. The objective of this study was to estimate genetic parameters for fertility traits in Chinese Holstein heifers and cows. Data of 20169 animals with 42106 records over a period of 10 yr (2001–2010) were collected from Sanyuan Lvhe Dairy Cattle Center in Beijing, China. Traits included age at first service (AFS), number of services (NS), days from calving to first service (CTFS), days open (DO), and calving interval (CI). Genetic parameters were estimated with multiple-trait animal model using the DMU software. Heritability estimates for AFS, NS, CTFS, DO and CI were 0.100±0.012, 0.040±0.017, 0.034±0.011, 0.053±0.019 and 0.056±0.014, respectively. Genetic correlations between traits observed ranged from −0.13 to 0.99. Genetic correlations between AFS with NS, CTFS, DO and CI were −0.31, 0.15, −0.13 and −0.15, respectively. Calving interval was strongly correlated with NS, CTFS and DO (0.49–0.99), and DO showed strong correlation with NS and CTFS (0.49 and 0.58, respectively). The genetic correlation between CTFS and NS was negative moderate (−0.25). Results were in range with previous literature estimates and can be used in Chinese Holstein genetic evaluation for fertility traits.
Genetic variation ofRhizoctonia solaniisolates from canola in Alberta, Canada
Authors: Zhou Q. X. , Hwang S. F. , Fu H. T. , Strelkov S. E. , Gossen B. D.
Published: December 2013

Zhou, Q. X., Hwang, S. F., Fu, H. T., Strelkov, S. E. and Gossen, B. D. 2014. Genetic variation of Rhizoctonia solani isolates from canola in Alberta, Canada. Can. J. Plant Sci. 94: 671–681. Seedling blight and root rot caused by Rhizoctonia solani often results in severe reductions in plant stands of canola (Brassica napus), a major oilseed crop in Canada. A total of 98 R. solani isolates were collected from central Alberta in 2009–2011 and analyzed for aggressiveness, anastomosis grouping and genetic variation. Seventy-six isolates (78%) were identified as AG2-1, three (3%) were AG2-2, one (1%) was AG4, one (1%) was AG8, and the anastomosis group of 17 isolates (17%) could not be determined. Isolates of AG2-1 were more aggressive on canola than the other isolates. The genetic variation among the 98 isolates was evaluated by sequence analysis of the ribosomal DNA internal transcribed spacers (ITS) and inter-simple sequence repeat (ISSR) markers. The isolates clustered into four groups based on a neighbor-joining tree of the ITS sequences using PAUP software, and four groups based on ISSR markers using the POPGENE program. The isolate composition of Group A in both clustering approaches was similar, and those isolates were weakly aggressive on canola seedlings. Although the identities of both groups differed, Groups B and C in both analyses included most of the AG2-1 isolates, which were highly aggressive on canola seedlings. Isolates with undetermined anastomosis grouping and isolates classified as AG4, AG8 or AG2-2 were also included in Groups B and C, but were generally less aggressive than the AG2-1 isolates. Group D consisted of only three isolates in both analyses, but their identities also differed. The results indicated that there was no association between Groups from the two molecular approaches.
Modeling of phosphorus dynamics in contrasting agroecosystems using long-term field experiments
Authors: Morel Christian , Ziadi Noura , Messiga Aimé , Bélanger Gilles , Denoroy Pascal , Jeangros Bernard , Jouany Claire , Fardeau Jean-Claude , Mollier Alain , Parent Léon-Etienne , Proix Nicolas , Rabeharisoa Lilia , Sinaj Sokrat
Published: December 2013

Morel, C., Ziadi, N., Messiga, A., Bélanger, G., Denoroy, P., Jeangros, B., Jouany, C., Fardeau, J. C., Mollier, A., Parent, L. E., Proix, N., Rabeharisoa, L. and Sinaj, S. 2014. Modeling of phosphorus dynamics in contrasting agroecosystems using long-term field experiments. Can. J. Soil Sci. 94: 377–387. Long-term field experiments on phosphorus (P) fertilization were originally designed to study crop needs in different soil types by analyzing the effects of several rates of P fertilization on yields, their P concentrations and dynamics of plant-available soil P. The objective of this study was to test a computer-based model to simulate the P dynamics at the field scale using plant database and analyzing for plant-available P by a hierarchical process-based approach. It predicts both the concentration (CP) of phosphate ions (Pi) in soil solution and the associated Pi amounts that in time equilibrate with Pi in solution. Five experiments, representative of contrasting soil types, land-use, and climates were selected. Our model equilibrates the change in plant-available P in the upper soil layer to the P budget between annual P inputs and outputs. Rates of P fertilization affected simulations following the same expected pattern across sites. Field-observed and simulated values are in good agreements in all sites. The field-observed variations of CP per unit of P budget ranged from 0.007 to 2.49 (µg P L−1) (kg P ha−1)−1. The predictions are of the same order of magnitude. Predictions were compared with empirical long-term data and mismatches were discussed. This investigation highlights the scientific interest of long-term field P experiments to test and validate models describing P dynamics at the scale of the agricultural fields under different agricultural management practices.
Auroral spectral estimation with wide-band color mosaic CCDs
Authors: Jackel B. J. , Unick C. , Syrjäsuo M. T. , Partamies N. , Wild J. A. , Woodfield E. E. , McWhirter I. , Kendall E. , Spanswick E.
Published: December 2013

Abstract. Color mosaic CCDs use a matrix of different wide-band micro-filters in order to produce images with several (often three) color channels. These devices are increasingly employed in auroral studies to provide time sequences of two dimensional luminosity maps, but the color information is typically only used for qualitative analysis. In this study we use Backus–Gilbert linear inversion techniques to obtain quantitative measures of effective spectral resolution for multi-channel color mosaic CCDs. These techniques also allow us to explore the possibility of further improvements by modifying or combining multiple detectors. We consider two spectrally calibrated commercial color CCDs (Sony ICX285AQ and ICX429AKL) in order to determine effective wavelength resolution of each device individually, together, and with additional filters. From these results we develop methods to enhance the utility of existing data sets, and propose ways to improve the next generation of low-cost color auroral imaging systems.
Development of a variational flux inversion system (INVICAT v1.0) within the TOMCAT chemical transport model
Authors: Wilson C. , Chipperfield M. P. , Gloor M. , Chevallier F.
Published: December 2013

Abstract. We present a new variational inverse transport model, named INVICAT (v1.0), which is based upon the global chemical transport model TOMCAT, and a new corresponding adjoint transport model, ATOMCAT. The adjoint model is constructed through manually derived discrete adjoint algorithms, and includes subroutines governing advection, convection and boundary layer mixing. We present extensive testing of the adjoint and inverse models, and also thoroughly assess the accuracy of the TOMCAT forward model's representation of atmospheric transport through comparison with observations of the atmospheric trace gas SF6. The forward model is shown to perform well in comparison with these observations, capturing the latitudinal gradient and seasonal cycle of SF6 to within acceptable tolerances. The adjoint model is shown, through numerical identity tests and novel transport reciprocity tests, to be extremely accurate in comparison with the forward model, with no error shown at the level of accuracy possible with our machines. The potential for the variational system as a tool for inverse modelling is investigated through an idealised test using simulated observations, and the system demonstrates an ability to retrieve known fluxes from a perturbed state accurately. Using basic off-line chemistry schemes, the inverse model is ready and available to perform inversions of trace gases with relatively simple chemical interactions, including CH4, CO2 and CO.
Understanding mean transit times in Andean tropical montane cloud forest catchments: combining tracer data, lumped parameter models and uncertainty analysis
Authors: Timbe E. , Windhorst D. , Crespo P. , Frede H.-G. , Feyen J. , Breuer L.
Published: December 2013

Abstract. Weekly samples from surface waters, springs, soil water and rainfall were collected in a 76.9 km2 mountain rain forest catchment and its tributaries in southern Ecuador. Time series of the stable water isotopes δ18O and δ2H were used to calculate mean transit times (MTTs) and the transit time distribution functions (TTDs) solving the convolution method for seven lumped parameter models. For each model setup, the Generalized Likelihood Uncertainty Estimation (GLUE) methodology was applied to find the best predictions, behavioral solutions and parameter identifiability. For the study basin, TTDs based on model types such as the Linear-Piston Flow for soil waters and the Exponential-Piston Flow for surface waters and springs performed better than more versatile equations such as the Gamma and the Two Parallel Linear Reservoirs. Notwithstanding both approaches yielded a better goodness of fit for most sites, but with considerable larger uncertainty shown by GLUE. Among the tested models, corresponding results were obtained for soil waters with short MTTs (ranging from 3 to 12 weeks). For waters with longer MTTs differences were found, suggesting that for those cases the MTT should be based at least on an intercomparison of several models. Under dominant baseflow conditions long MTTs for stream water ≥2 yr were detected, a phenomenon also observed for shallow springs. Short MTTs for water in the top soil layer indicate a rapid exchange of surface waters with deeper soil horizons. Differences in travel times between soils suggest that there is evidence of a land use effect on flow generation.
Toward a possible next geomagnetic transition?
Authors: De Santis A. , Qamili E. , Wu L.
Published: December 2013

Abstract. The geomagnetic field is subject to possible reversals or excursions of polarity during its temporal evolution. Considering that: (a) in the last 83 million yr the typical average time between one reversal and the next (the so-called chron) is around 400 000 yr, (b) the last reversal occurred around 780 000 yr ago, (c) more excursions (rapid changes in polarity) can occur within the same chron and (d) the geomagnetic field dipole is currently decreasing, a possible imminent geomagnetic reversal or excursion would not be completely unexpected. In that case, such a phenomenon would represent one of the very few natural hazards that are really global. The South Atlantic Anomaly (SAA) is a great depression of the geomagnetic field strength at the Earth's surface, caused by a reverse magnetic flux in the terrestrial outer core. In analogy with critical point phenomena characterized by some cumulative quantity, we fit the surface extent of this anomaly over the last 400 yr with power law or logarithmic functions in reverse time, also decorated by log-periodic oscillations, whose final singularity (a critical point tc) reveals a great change in the near future (2034 ± 3 yr), when the SAA area reaches almost a hemisphere. An interesting aspect that has recently been found is the possible direct connection between the SAA and the global mean sea level (GSL). That the GSL is somehow connected with SAA is also confirmed by the similar result when an analogous critical-like fit is performed over GSL: the corresponding critical point (2033 ± 11 yr) agrees, within the estimated errors, with the value found for the SAA. From this result, we point out the intriguing conjecture that tc would be the time of no return, after which the geomagnetic field could fall into an irreversible process of a global geomagnetic transition that could be a reversal or excursion of polarity.
Maximising the usefulness of flood risk assessment for the River Vistula in Warsaw
Authors: Kiczko A. , Romanowicz R. J. , Osuch M. , Karamuz E.
Published: December 2013

Abstract. The derivation of the flood risk maps requires an estimation of maximum inundation extent for a flood with a given return period, e.g. 100 or 500 yr. The results of numerical simulations of flood wave propagation are used to overcome the lack of relevant observations. In practice, deterministic 1-D models are used for that purpose. The solution of a 1-D model depends on the initial and boundary conditions and estimates of model parameters based on the available noisy observations. Therefore, there is a large uncertainty involved in the derivation of flood risk maps using a single realisation of a flow model. Bayesian conditioning based on multiple model simulations can be used to quantify this uncertainty; however, it is too computer-time demanding to be applied in flood risk assessment in practice, without further flow routing model simplifications. We propose robust and feasible methodology for estimating flood risk. In order to decrease the computation times the assumption of a gradually varied flow and the application of a steady state flow routing model is introduced. The aim of this work is an analysis of the influence of those simplifying assumptions and uncertainty of observations and modelling errors on flood inundation mapping and a quantitative comparison with deterministic flood extent maps. Apart from the uncertainty related to the model structure and its parameters, the uncertainty of the estimated flood wave with a specified probability of return period (so-called 1-in-10 yr, or 1-in-100 yr flood) is also taken into account. In order to derive the uncertainty of inundation extent conditioned on the design flood, the probabilities related to the design wave and flow model uncertainties are integrated. In the present paper that integration is done whilst taking into account the dependence of roughness coefficients on discharge. The roughness is parameterised based on maximum annual discharges. This approach allows for the relationship between flood extent and flow values to be derived, thus giving a cumulative assessment of flood risk. The methods are illustrated using the Warsaw reach of the River Vistula as a case study. The results indicate that deterministic and stochastic flood inundation maps cannot be quantitatively compared. We show that the proposed simplified approach to flood risk assessment can be applied even when breaching of the embankment occurs, with the condition that the flooded area is small enough to be filled rapidly.
An interdisciplinary approach to volcanic risk reduction under conditions of uncertainty: a case study of Tristan da Cunha
Authors: Hicks A. , Barclay J. , Simmons P. , Loughlin S.
Published: December 2013

Abstract. This research project adopted an interdisciplinary approach to volcanic risk reduction on the remote volcanic island of Tristan da Cunha (South Atlantic). New data were produced that: (1) established no spatio-temporal pattern to recent volcanic activity; (2) quantified the high degree of scientific uncertainty around future eruptive scenarios; (3) analysed the physical vulnerability of the community as a consequence of their geographical isolation and exposure to volcanic hazards; (4) evaluated social and cultural influences on vulnerability and resilience. Despite their isolation and prolonged periods of hardship, islanders have demonstrated an ability to cope with and recover from adverse events. This resilience is likely a function of remoteness, strong kinship ties, bonding social capital, and persistence of shared values and principles established at community inception. While there is good knowledge of the styles of volcanic activity on Tristan, given the high degree of scientific uncertainty about the timing, size and location of future volcanism, a qualitative scenario planning approach was used as a vehicle to convey this information to the islanders. This deliberative, anticipatory method allowed on-island decision makers to take ownership of risk identification, management and capacity building within their community. This paper demonstrates the value of integrating social and physical sciences with development of effective, tailored communication strategies in volcanic risk reduction.
The effect of climate forcing on numerical simulations of the Cordilleran ice sheet at the Last Glacial Maximum
Authors: Seguinot J. , Khroulev C. , Rogozhina I. , Stroeven A. P. , Zhang Q.
Published: December 2013

Abstract. We present an ensemble of numerical simulations of the Cordilleran ice sheet during the Last Glacial Maximum performed with the Parallel Ice Sheet Model (PISM), applying temperature offsets to the present-day climatologies from five different datasets. Monthly mean surface air temperature and precipitation from WorldClim, the NCEP/NCAR reanalysis, the ERA-Interim reanalysis, the Climate Forecast System Reanalysis and the North American Regional Reanalysis are used to compute surface mass balance in a positive degree-day model. Modelled ice sheet outlines and volumes appear highly sensitive to the choice of climate forcing. For three of the four reanalysis datasets used, differences in precipitation are the major source for discrepancies between model results. We assess model performance against a geomorphological reconstruction of the ice margin at the Last Glacial Maximum, and suggest that part of the mismatch is due to unresolved orographic precipitation effects caused by the coarse resolution of reanalysis data. The best match between model output and the reconstructed ice margin is obtained using the high-resolution North American Regional Reanalysis, which we retain for simulations of the Cordilleran ice sheet in the future.
Postglacial rebound and relative sea level changes in the Baltic Sea since the Litorina transgression
Authors: Rosentau Alar , Harff Jan , Meyer Michael , Oja Tõnis
Published: December 2013

Based on geostatistical modelling the authors compared relative sea level records for the Litorina and post-Litorina Sea with tide gauge and GPS derived crustal velocity measurements in Fennoscandia and in the Baltic region. Results show good fit between the geological record and GPS derived crustal velocity measurements indicating that the postglacial rebound (PGR) centre on the northwest coast of the Bothnian Sea and the isostatic zero-line in the southern Baltic remained stable during the last 8000 14C yrs BP (8900 cal yrs BP). An average Baltic Sea level rise of 1.4±0.4 mm/y for the 20th century was estimated, which is found to be at about one fifth compared to the mid-Holocene sea level rise. However, considering the recent estimates of eustatic sea level rise for the 21st century the slowly uplifting coastal areas in southern Sweden, SE Finland, Estonia, Latvia and NW Russia, which have experienced a long term relative sea level fall, will probably also be affected by future sea level rise reminiscent of the mid-Holocene one.
Geological and environmental pre-conditions for utilisation of the Maardu granite deposit, northern Estonia
Authors: Metsur Mait , Metsur Madis , Niitlaan Erki , Raukas Anto , Siitam Peep
Published: December 2013

Efficient use of natural resources is a global goal. A specific way of improving resource productivity in Estonia is utilisation of Maardu granite deposit as a joint goal for producing granite aggregates and construction in the caverns of the granite mine and a pumped hydroaccumulation plant. The environmental impact assessment in connection with construction of a Maardu deep granite mine was accepted by the Estonian Ministry of Environment in 2009. The most challenging engineering task, causing also the biggest environmental risks, is safe penetration of aquifers and aquitards during construction of vertical and/or inclined tunnels for granite mine and/or pumped hydroaccumulation plant. A major problem is also the high radiation level in the Maardu area and in the planned deep mine. High radon concentrations up to 10 000 Bq/m3 have been recorded on the outcrops of alum shale in the mine area and they can be dangerous to human health. Based on the hydrogeological modelling it was found, that under normal circumstances the construction and operation of the Maardu deep granite mine is environmentally safe. The territory of the former Maardu phosphorite opencast is highly polluted and damaged and therefore the foundation of the granite mine with overground buildings is the best way for the environmental improving of the area.
Dryness dynamics of the Baltic Sea region
Authors: Rimkus Egidijus , Valiukas Donatas , Kažys Justas , Gečaitė Indrė , Stonevičius Edvinas
Published: December 2013

The dynamics in dryness over the Baltic Sea region during the observation period of 1960–2009, as well as the climate prediction for the 21st century have been evaluated in this research. The dryness of the investigated area has been examined using the Standardized Precipitation Index (SPI). The precipitation amount data provided by the Climate Research Unit (CRU) at the University of East Anglia have been used in this study. Projections of future dryness changes are based on the output data of the regional CCLM model driven by A1B and B1 emission scenarios. The increase of SPI values, i.e. a decline in dryness, have been found over the last fifty years in the major part of the investigated area. However, the probability of short-term droughts remain high against the background of a general decrease in dryness. The increased dryness during the analyzed period has been found only in the southern part of the Baltic Sea region. Similar changes are also foreseen for the 21st century. The dryness is expected to increase in the south (especially in summer), while the central and northern parts of the region are likely to witness the recurrence of a drought decrease.