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Registros recuperados: 57 | |
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Torres Guerrero, Carlos Alberto. |
Los suelos de México han sido degradados en los últimos años en buena parte por la acción del hombre. Debido a las prácticas agronómicas empleadas en la mayor parte del país (labranza convencional, monocultivos y remoción de residuos vegetales de cosechas anteriores) los suelos con potencial agrícola se han visto disminuidos en su productividad. La Agricultura de Conservación (AC) ofrece un aprovechamiento sustentable del recurso suelo, asegurando su estabilidad y estructura, con el propósito de aumentar los rendimientos de los cultivos. El experimento que se reporta es de larga duración. Se inició en 1991 en el Batán Texcoco, Estado de México, en el Centro Internacional de Mejoramiento de Maíz y Trigo (CIMMYT) y consta de 32 parcelas con diferentes... |
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Palavras-chave: Labranza; Agricultura de conservación; Raíces; Agregación; Maestría; Edafología; Tillage; Conservation agriculture; Roots; Aggregation. |
Ano: 2012 |
URL: http://hdl.handle.net/10521/1755 |
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Petitgas, Pierre; Woillez, Mathieu; Doray, Mathieu; Rivoirard, Jacques. |
Marine research survey data on fish stocks often show a small proportion of very high-density values, as for many environmental data. This makes the estimation of second-order statistics, such as the variance and the variogram, non-robust. The high fish density values are generated by fish aggregative behaviour, which may vary greatly at small scale in time and space. The high values are thus imprecisely known, both in their spatial occurrence and order of magnitude. To map such data, three indicator-based geostatistical methods were considered, the top-cut model, min–max autocorrelation factors (MAF) of indicators, and multiple indicator kriging. In the top-cut and MAF approaches, the variable is decomposed into components and the most continuous ones... |
Tipo: Text |
Palavras-chave: Top-cut; MAF; Indicators; Co-kriging; Skewed distribution; Anchovy; Bay of Biscay; Fisheries survey data; Aggregation. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00429/54021/55339.pdf |
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Tallec, Kevin; Blard, Océane; González-fernández, Carmen; Brotons, Guillaume; Berchel, Mathieu; Soudant, Philippe; Huvet, Arnaud; Paul-pont, Ika. |
Plastic debris are classified as a function of their size and recently a new class was proposed, the nanoplastics. Nano-sized plastics have a much greater surface area to volume ratio than larger particles, which increases their reactivity in aquatic environment, making them potentially more toxic. Only little information is available about their behavior whereas it crucially influences their toxicity. Here, we used dynamic light scattering (DLS) to explore the influence of environmental factors (fresh- and saltwater, dissolved organic matter) on the behavior (surface charge and aggregation state) of three different nano-polystyrene beads (50 nm), with (i) no surface functionalization (plain), (ii) a carboxylic or (iii) an amine functionalization. Overall,... |
Tipo: Text |
Palavras-chave: Nanoplastic; Dynamic light scattering; Behavior; Aggregation; Salinity; Organic matter. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00485/59652/62684.pdf |
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Laurenceau-cornec, Emmanuel C.; Trull, Thomas W.; Davies, Diana M.; De La Rocha, Christina L.; Blain, Stephane. |
During the second KErguelen Ocean and Plateau compared Study (KEOPS2) in October-November 2011, marine snow was formed in roller tanks by physical aggregation of phytoplankton assemblages sampled at 6 stations over and downstream of the Kerguelen Plateau. Sinking velocities, morphology, bulk composition (transparent exopolymer particles, biogenic silica, particulate organic carbon), and phytoplankton contents were measured individually on 66 aggregates to identify controls on sinking velocities. Equivalent spherical diameters (ESD) ranged from 1 to 12 mm, and the particle aspect ratios, Corey shape factors, and fractal dimensions (D-F1 = 1.5, D-F2 = 1.8) were close to those of smaller natural aggregates (0.2 to 1.5 mm) collected in polyacrylamide... |
Tipo: Text |
Palavras-chave: Sinking velocity Marine snow; Aggregation; Phytoplankton; Porosity. |
Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00352/46275/46044.pdf |
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Maillet, A; Congy Jolivet, N; Le Guellec, S; Vecellio, L; Hamard, S; Courty, Y; Courtois, Anthony; Gauthier, F; Diot, P; Thibault, G; Lemarie, E; Heuze Vourc' H, N. |
Purpose. Despite an increasing interest in the use of inhalation for local delivery of molecules for respiratory diseases and systemic disorders, methods to deliver therapy through air-ways has received little attention for lung cancer treatment. However, inhalation of anticancer drugs is an attractive alternative route to systemic administration which results in limited concentration of the medication in the lungs, and triggers whole-body toxicity. In this study, we investigated the feasibility of nebulization for therapeutic antibodies, a new class of fully-approved anticancer drugs in oncology medicine. Materials and methods. Cetuximab, a chimeric IgG1 targeting the epidermal growth factor receptor (EGER), was nebulized using three types of delivery... |
Tipo: Text |
Palavras-chave: Nebulizer; Lung cancer; Cetuximab; Anticancer antibody; Aggregation; Aerosol. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4201.pdf |
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Hirose,Edson; Panizzi,Antônio R.; Cattelan,Alexandre J.. |
Laboratory studies with 1st instar of southern green stink bug, Nezara viridula (L.) indicated that relative humidity (RH) greatly affected nymph emergence and survivorship up to the 2nd instar, reaching the maximum value (<FONT FACE=Symbol>»</FONT> 90%) with RH of > 80%. At 60% RH, 60% of the nymphs emerged and survived, while with 0% RH only <FONT FACE=Symbol>»</FONT> 15% of eggs hatched, and most nymphs died. Emerged nymphs from egg masses placed in plastic boxes with a gradient of humidity remained on egg shells for ca. one day. After this period, they dispersed and regrouped on top of shells 6.8 ± 0.67 times, until they abandoned the shells toward the source of humidity, avoiding the water-saturated areas. Duration taken for... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Heteroptera; Stink bug; Behavior; Aggregation; Microclimate. |
Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1519-566X2006000600006 |
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Moraes,Maria C.B.; Pareja,Martín; Laumann,Raúl A.; Borges,Miguel. |
In recent years the growing concern about environmental changes and how we are using the natural resources have triggered a search for natural products as alternatives to synthetic pesticides. The stink bugs produce a wide variety of chemical compounds (semiochemicals) that show potential to manage these insects. The stink bugs Chinavia impicticornis (Stål), C. ubica (Rolston), Dichelops melacanthus (Dallas), Euschistus heros (F.), Piezodorus guildinii (Westwood), Thyanta perditor (Westwood) and Tibraca limbativentris (Stål) had their blends of defensive compounds evaluated both qualitative and quantitatively. The main compounds identified on the glands of Brazilian stink bugs are: 2-alkenals, mainly the E isomer; saturated aliphatic hydrocarbons; and 4... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Pheromone; Allelochemical; Aggregation; Behaviour; Soybean. |
Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1519-566X2008000500001 |
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Caballero, Ricardo J.; Engel, Eduardo M.R.A.. |
In most instances, the dynamic response of monetary and other policies to shocks is infrequent and lumpy. The same holds for the microeconomic response of some of the most important economic variables, such as investment, labor demand, and prices. We show that the standard practice of estimating the speed of adjustment of such variables with partial-adjustment ARMA procedures substantially overestimates this speed. For example, for the target federal funds rate, we find that the actual response to shocks is less than half as fast as the estimated response. For investment, labor demand and prices, the speed of adjustment inferred from aggregates of a small number of agents is likely to be close to instantaneous. While aggregating across microeconomic units... |
Tipo: Working or Discussion Paper |
Palavras-chave: Speed of adjustment; Discrete adjustment; Lumpy adjustment; Aggregation; Calvo model; ARMA process; Partial adjustment; Expected response time; Monetary policy; Investment; Labor demand; Sticky prices; Idiosyncratic shocks; Impulse response function; Wold representation; Time-to-build; Financial Economics; C22; C43; D2; E2; E5. |
Ano: 2003 |
URL: http://purl.umn.edu/28419 |
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Registros recuperados: 57 | |
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