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https://www.readbyqxmd.com/read/29331892/dynamic-probabilistic-material-flow-analysis-of-nano-sio2-nano-iron-oxides-nano-ceo2-nano-al2o3-and-quantum-dots-in-seven-european-regions
#1
Yan Wang, Bernd Nowack
Static environmental exposure assessment models based on material flow analysis (MFA) have previously been used to estimate flows of engineered nanomaterials (ENMs) to the environment. However, such models do not account for changes in the system behavior over time. Dynamic MFA used in this study includes the time-dependent development of the modelling system by considering accumulation of ENMs in stocks and the environment, and the dynamic release of ENMs from nano-products. In addition, this study also included regional variations in population, waste management systems, and environmental compartments, which subsequently influence the environmental release and concentrations of ENMs...
January 11, 2018: Environmental Pollution
https://www.readbyqxmd.com/read/29331854/trade-offs-between-forest-carbon-stocks-and-harvests-in-a-steady-state-a-multi-criteria-analysis
#2
Kim Pingoud, Tommi Ekholm, Risto Sievänen, Saija Huuskonen, Jari Hynynen
This paper provides a perspective for comparing trade-offs between harvested wood flows and forest carbon stocks with different forest management regimes. A constant management regime applied to a forest area with an even age-class distribution leads to a steady state, in which the annual harvest and carbon stocks remain constant over time. As both are desirable - carbon stocks for mitigating climate change and harvests for the economic use of wood and displacing fossil fuels - an ideal strategy should be chosen from a set of management regimes that are Pareto-optimal in the sense of multi-criteria decision-making...
January 11, 2018: Journal of Environmental Management
https://www.readbyqxmd.com/read/29321870/contrasting-genetic-metrics-and-patterns-among-naturalized-rainbow-trout-oncorhynchus-mykiss-in-two-patagonian-lakes-differentially-impacted-by-trout-aquaculture
#3
Cristian B Canales-Aguirre, Lisa W Seeb, James E Seeb, María I Cádiz, Selim S Musleh, Ivan Arismendi, Gonzalo Gajardo, Ricardo Galleguillos, Daniel Gomez-Uchida
Different pathways of propagation and dispersal of non-native species into new environments may have contrasting demographic and genetic impacts on established populations. Repeated introductions of rainbow trout (Oncorhynchus mykiss) to Chile in South America, initially through stocking and later through aquaculture escapes, provide a unique setting to contrast these two pathways. Using a panel of single nucleotide polymorphisms, we found contrasting genetic metrics and patterns among naturalized trout in Lake Llanquihue, Chile's largest producer of salmonid smolts for nearly 50 years, and Lake Todos Los Santos (TLS), a reference lake where aquaculture has been prohibited by law...
January 2018: Ecology and Evolution
https://www.readbyqxmd.com/read/29298484/looking-down-under-for-a-circular-economy-of-indium
#4
Tim T Werner, Luca Ciacci, Gavin Mark Mudd, Barbara K Reck, Stephen Alan Northey
Indium is a specialty metal crucial for modern technology, yet potentially critical due to its by-product status in mining. Measures to reduce its criticality typically focus on improving its recycling efficiency at end-of-life. This study quantifies primary and secondary indium resources ("stocks") for Australia through a dynamic material flow analysis. It is based on detailed assessments of indium mineral resources hosted in lead-zinc and copper deposits, respective mining activities from 1844-2013, and the trade of indium-containing products from 1988-2015...
January 4, 2018: Environmental Science & Technology
https://www.readbyqxmd.com/read/29274609/trends-and-seasonality-of-river-nutrients-in-agricultural-catchments-18years-of-weekly-citizen-science-in-france
#5
Benjamin W Abbott, Florentina Moatar, Olivier Gauthier, Ophélie Fovet, Virginie Antoine, Olivier Ragueneau
Agriculture and urbanization have disturbed three-quarters of global ice-free land surface, delivering huge amounts of nitrogen and phosphorus to freshwater ecosystems. These excess nutrients degrade habitat and threaten human food and water security at a global scale. Because most catchments are either currently subjected to, or recovering from anthropogenic nutrient loading, understanding the short- and long-term responses of river nutrients to changes in land use is essential for effective management. We analyzed a never-published, 18-year time series of anthropogenic (NO3- and PO43-) and naturally derived (dissolved silica) riverine nutrients in 13 catchments recovering from agricultural pollution in western France...
December 20, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/29240066/peculiarities-of-vitalization-of-grafts-made-of-porous-polytetrafluoroethylene-in-reconstruction-of-major-veins-an-experimental-study
#6
S É Voskanian, M V Shabalin, A V Volkov, I Iu Kolyshev
Increased incidence of locally disseminated malignant neoplasms with invasion of major veins compels modern surgery to search for an optimal material for reconstruction of major veins. Presented herein are the results of an experimental study aimed at exploring patency and peculiarities of vitalization of grafts made of porous polytetrafluoroethylene (7th generation, 2010) manufactured by the Closed Joint Stock Company 'Research and Production Complex 'Ecoflon' (St. Petersburg, Russia) with an internal diameter measuring 4...
2017: Angiologii︠a︡ i Sosudistai︠a︡ Khirurgii︠a︡, Angiology and Vascular Surgery
https://www.readbyqxmd.com/read/29225415/a-co-flow-structure-for-goal-directed-internal-change
#7
Pascal Gambardella, Deborah E Polk, David Lounsbury, Ralph Levine
We describe a co-flow structure that models internal, goal-directed changes to an attribute (e.g., employee loyalty) of fundamental material (e.g., employees). This co-flow accommodates problems not adequately modeled with an existing, generic structure. Our structure builds on the co-flow proposed by Hines, which uses an information delay to model external change to an attribute. We use a first-order information delay to model both external changes to the attribute from the material stock and internal changes from an internal goal for the attribute...
January 2017: System Dynamics Review
https://www.readbyqxmd.com/read/29225368/rates-intrinsic-linkages-and-multistate-population-dynamics
#8
Robert Schoen
Demographic analyses of multistate populations are commonplace, as are situations where population stocks are known but population flows are not. Still, demographic models for multistate populations with changing rates remain at an early stage of development, limiting dynamic analyses and analytical projections. Here, a new approach, the Intrinsic Linkage-Rate Ratio (IL-RR) model, is presented and explored. The key IL parameter, w, is a simple weight for projecting populations. Using the ultimate state composition implied by the prevailing rates, the IL-RR model provides new relationships that connect multistate populations over time and allow analytical population projections...
2017: Genus
https://www.readbyqxmd.com/read/29217324/-medical-human-resources-planning-in-europe-a-literature-review-of-the-forecasting-models
#9
N Benahmed, D Deliège, A De Wever, M Pirson
BACKGROUND: Healthcare is a labor-intensive sector in which half of the expenses are dedicated to human resources. Therefore, policy makers, at national and internal levels, attend to the number of practicing professionals and the skill mix. This paper aims to analyze the European forecasting model for supply and demand of physicians. METHODS: To describe the forecasting tools used for physician planning in Europe, a grey literature search was done in the OECD, WHO, and European Union libraries...
December 4, 2017: Revue D'épidémiologie et de Santé Publique
https://www.readbyqxmd.com/read/29216467/drivers-of-dissolved-organic-carbon-export-in-a-subarctic-catchment-importance-of-microbial-decomposition-sorption-desorption-peatland-and-lateral-flow
#10
Jing Tang, Alla Y Yurova, Guy Schurgers, Paul A Miller, Stefan Olin, Benjamin Smith, Matthias B Siewert, David Olefeldt, Petter Pilesjö, Anneli Poska
Tundra soils account for 50% of global stocks of soil organic carbon (SOC), and it is expected that the amplified climate warming in high latitude could cause loss of this SOC through decomposition. Decomposed SOC could become hydrologically accessible, which increase downstream dissolved organic carbon (DOC) export and subsequent carbon release to the atmosphere, constituting a positive feedback to climate warming. However, DOC export is often neglected in ecosystem models. In this paper, we incorporate processes related to DOC production, mineralization, diffusion, sorption-desorption, and leaching into a customized arctic version of the dynamic ecosystem model LPJ-GUESS in order to mechanistically model catchment DOC export, and to link this flux to other ecosystem processes...
December 4, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/29205516/a-tripartite-mode-of-action-approach-for-investigating-the-impact-of-aneugens-on-tubulin-polymerization
#11
Valerie Stock, Andreas Sutter, Marian Raschke, Nina Queisser
Chemical-induced disruption of the cellular microtubule network is one key mechanism of aneugenicity. Since recent data indicate that genotoxic effects of aneugens show nonlinear dose-response relationships, margins of safety can be derived with the ultimate goal to perform a risk assessment for the support of drug development. Furthermore, microtubule-interacting compounds are widely used for cancer treatment. While there is a need to support the risk assessment of tubulin-interacting chemicals using reliable mechanistic assays, no standard assays exist to date in regulatory genotoxicity testing for the distinction of aneugenic mechanisms...
December 4, 2017: Environmental and Molecular Mutagenesis
https://www.readbyqxmd.com/read/29194544/numbers-systems-people-how-interactions-influence-integration-insights-from-case-studies-of-hiv-and-reproductive-health-services-delivery-in-kenya
#12
Susannah H Mayhew, Sedona Sweeney, Charlotte E Warren, Martine Collumbien, Charity Ndwiga, Richard Mutemwa, Irina Lut, Manuela Colombini, Anna Vassall
Drawing on rich data from the Integra evaluation of integrated HIV and reproductive-health services, we explored the interaction of systems hardware and software factors to explain why some facilities were able to implement and sustain integrated service delivery while others were not. This article draws on detailed mixed-methods data for four case-study facilities offering reproductive-health and HIV services between 2009 and 2013 in Kenya: (i) time-series client flow, tracking service uptake for 8841 clients; (ii) structured questionnaires with 24 providers; (iii) in-depth interviews with 17 providers; (iv) workload and facility data using a periodic activity review and cost-instruments; and (v) contextual data on external activities related to integration in study sites...
November 1, 2017: Health Policy and Planning
https://www.readbyqxmd.com/read/29190125/mitotic-instability-in-triploid-and-tetraploid-one-year-old-eastern-oyster-crassostrea-virginica-assessed-by-cytogenetic-and-flow-cytometry-techniques
#13
Joana Teixeira Sousa, Standish Allen, Brittany M Wolfe, Jessica Moss Small
For commercial oyster aquaculture, triploidy has significant advantages. To produce triploids, the principal technology uses diploid x tetraploid crosses. The development of tetraploid brood stock for this purpose has been successful, but as more is understood about tetraploids, it seems clear that chromosome instability is a principal feature in oysters. This paper is a continuation of work to investigate chromosome instability in polyploid Crassostrea virginica. We established families between tetraploids - apparently stable (non-mosaic) and unstable (mosaic) - and normal reference diploids, creating triploid groups, as well as tetraploids between mosaic and non-mosaic tetraploids...
November 30, 2017: Genome Génome / Conseil National de Recherches Canada
https://www.readbyqxmd.com/read/29170508/differential-distribution-of-y-chromosome-haplotypes-in-swiss-and-southern-european-goat-breeds
#14
Oriol Vidal, Cord Drögemüller, Gabriela Obexer-Ruff, Irene Reber, Jordi Jordana, Amparo Martínez, Valentin Adrian Bâlteanu, Juan Vicente Delgado, Shahin Eghbalsaied, Vincenzo Landi, Felix Goyache, Amadou Traoré, Michele Pazzola, Giuseppe Massimo Vacca, Bouabid Badaoui, Fabio Pilla, Mariasilvia D'Andrea, Isabel Álvarez, Juan Capote, Abdoallah Sharaf, Àgueda Pons, Marcel Amills
The analysis of Y-chromosome variation has provided valuable clues about the paternal history of domestic animal populations. The main goal of the current work was to characterize Y-chromosome diversity in 31 goat populations from Central Eastern (Switzerland and Romania) and Southern Europe (Spain and Italy) as well as in reference populations from Africa and the Near East. Towards this end, we have genotyped seven single nucleotide polymorphisms (SNPs), mapping to the SRY, ZFY, AMELY and DDX3Y Y-linked loci, in 275 bucks from 31 populations...
November 23, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29161278/resilience-of-honeybee-colonies-via-common-stomach-a-model-of-self-regulation-of-foraging
#15
Thomas Schmickl, Istvan Karsai
We propose a new regulation mechanism based on the idea of the "common stomach" to explain several aspects of the resilience and homeostatic regulation of honeybee colonies. This mechanism exploits shared pools of substances (pollen, nectar, workers, brood) that modulate recruitment, abandonment and allocation patterns at the colony-level and enable bees to perform several survival strategies to cope with difficult circumstances: Lack of proteins leads to reduced feeding of young brood, to early capping of old brood and to regaining of already spent proteins through brood cannibalism...
2017: PloS One
https://www.readbyqxmd.com/read/29156279/the-stocks-and-flows-of-nitrogen-phosphorus-and-potassium-across-a-30-year-time-series-for-agriculture-in-huantai-county-china
#16
Jessica Bellarby, Ben W J Surridge, Philip M Haygarth, Kun Liu, Giuseppina Siciliano, Laurence Smith, Clive Rahn, Fanqiao Meng
In order to improve the efficiency of nutrient use whilst also meeting projected changes in the demand for food within China, new nutrient management frameworks comprised of policy, practice and the means of delivering change are required. These frameworks should be underpinned by systemic analyses of the stocks and flows of nutrients within agricultural production. In this paper, a 30-year time series of the stocks and flows of nitrogen (N), phosphorus (P) and potassium (K) are reported for Huantai county, an exemplar area of intensive agricultural production in the North China Plain...
November 17, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/29153809/heartmate-iii-left-ventricular%C3%A2-assist-device-thrombosis-triggered-by-an%C3%A2-automatic-implantable-cardioverter-defibrillator-shock
#17
Stefan Klotz, Antje Karluss, Sina Stock, Alex Frydrychowicz, Hans-Hinrich Sievers
We report the case of an HeartMate III left ventricular assist device (LVAD) thrombosis triggered by a shock from an automatic implantable cardioverter defibrillator, releasing a left ventricular thrombus sucked in the LVAD inflow cannula. With LVAD low flow only the increase in motor temperature gave a hint of the thrombosis and a computer tomography scan confirmed the diagnosis. Pump exchange was performed with an uneventful outcome.
December 2017: Annals of Thoracic Surgery
https://www.readbyqxmd.com/read/29151854/strong-population-structure-deduced-from-genetics-otolith-chemistry-and-parasite-abundances-explains-vulnerability-to-localized-fishery-collapse-in-a-large-sciaenid-fish-protonibea%C3%A2-diacanthus
#18
Laura Taillebois, Diane P Barton, David A Crook, Thor Saunders, Jonathan Taylor, Mark Hearnden, Richard J Saunders, Stephen J Newman, Michael J Travers, David J Welch, Alan Greig, Christine Dudgeon, Safia Maher, Jennifer R Ovenden
As pressure on coastal marine resources is increasing globally, the need to quantitatively assess vulnerable fish stocks is crucial in order to avoid the ecological consequences of stock depletions. Species of Sciaenidae (croakers, drums) are important components of tropical and temperate fisheries and are especially vulnerable to exploitation. The black-spotted croaker, Protonibea diacanthus, is the only large sciaenid in coastal waters of northern Australia where it is targeted by commercial, recreational and indigenous fishers due to its food value and predictable aggregating behaviour...
December 2017: Evolutionary Applications
https://www.readbyqxmd.com/read/29149202/intraspecific-evolutionary-relationships-among-peregrine-falcons-in-western-north-american-high-latitudes
#19
Sandra L Talbot, George K Sage, Sarah A Sonsthagen, Meg C Gravley, Ted Swem, Jeffrey C Williams, Jonathan L Longmire, Skip Ambrose, Melanie J Flamme, Stephen B Lewis, Laura Phillips, Clifford Anderson, Clayton M White
Subspecies relationships within the peregrine falcon (Falco peregrinus) have been long debated because of the polytypic nature of melanin-based plumage characteristics used in subspecies designations and potential differentiation of local subpopulations due to philopatry. In North America, understanding the evolutionary relationships among subspecies may have been further complicated by the introduction of captive bred peregrines originating from non-native stock, as part of recovery efforts associated with mid 20th century population declines resulting from organochloride pollution...
2017: PloS One
https://www.readbyqxmd.com/read/29129064/impacts-of-combined-cooling-heating-and-power-systems-and-rainwater-harvesting-on-water-demand-carbon-dioxide-and-nox-emissions-for-atlanta
#20
Jean-Ann James, Sangwoo Sung, Hyunju Jeong, Osvaldo Alejandro Broesicke, Steve French, Duo Li, John C Crittenden
The purpose of this study is to explore the potential water, CO2 and NOx emission, and cost savings that the deployment of decentralized water and energy technologies within two urban growth scenarios can achieve. We assess the effectiveness of urban growth, technological, and political strategies to reduce these burdens in the 13-county Atlanta metropolitan region. The urban growth between 2005 and 2030 was modeled for a business as usual (BAU) scenario and a more compact growth (MCG) scenario. We considered combined cooling, heating and power (CCHP) systems using microturbines for our decentralized energy technology and rooftop rainwater harvesting and low flow fixtures for the decentralized water technologies...
November 11, 2017: Environmental Science & Technology
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