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161.
Delgado-Balbuena Laura Romero-Tepal Elda M. Luna-Guido Marco L. Marsch Rodolfo Dendooven Luc 《Water, air, and soil pollution》2013,224(2):1-8
Water, Air, &; Soil Pollution - Suspended microplastic and black carbon (BC) particles were determined in surface waters of the Jade system, southern North Sea, including freshwater sources. On... 相似文献
162.
Use of Lorenz curves and Gini coefficients to assess yield inequality within paddocks 总被引:1,自引:0,他引:1
The opportunity for site-specific management of crops depends on both the magnitude and spatial structure of yield variation. This study explored the applicability of Lorenz curves and Gini coefficients (G) to characterise the magnitude of the variation in grain yield. Maize crops were grown in farmers fields in a semi-arid region of central Argentina. Major sources of yield variation between and within paddocks included season, soil type and topography, rate of nitrogen fertiliser (nil to 132 kg N ha−1), and the interactions among these factors. Nitrogen treatments were applied in a complete block strip trial (strip size700 m×9.8 m) with three replicates. Data were collected with an AgLeader™ yield monitor, and GIS software was used to create 9.8 m×9.8 m grids over the observations. Average yield in 0.7–2.8 ha field sections ranged from 1.6 to 7.0 t ha−1. Gini coefficient ranged from 0.027 to 0.191 whereas its theoretical limits are 0 for a perfectly uniform population, and 1 for a theoretical population of infinite size where all units but one yield 0. Conditions conducive to high yield, e.g. adequate availability of nitrogen and water, reduced crop yield inequality, as quantified with G. The agronomic relevance of G was summarised in an inverse relationship with yield. Lorenz curves seemed particularly apt to present crop heterogeneity in terms of inequality, and to highlight the relative contribution of low- and high-yielding sections of the field to total paddock yield. Lorenz curves and Gini coefficients provide a potentially useful extension tool, a complement to yield maps and other statistical indices of yield variation, and further contact points between site-specific management, economics and ecology. 相似文献
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164.
Thais Grassi Gericó Renan Francisco Rimoldi Tavanti Jéssica Pacheco de Lima Rodolfo Pires Ribeiro Leandro Cesar Cusim dos Santos Marcio Souza da Silva 《Journal of plant nutrition》2020,43(12):1907-1922
AbstractThe objective of this study was to evaluate the effects of cobalt (Co) and molybdenum (Mo) doses in the treatment of seeds on the biosynthesis of nitrogen compounds, photosynthetic pigments, sugars, and production of peanut plants. The doses of Co and Mo used were 0, 2, 3, and 4?mL kg?1 seed, which were applied immediately before sowing. Seeds treated with Co and Mo at a dose of 4?mL kg?1 yielded peanut plants with higher concentrations of photosynthetic pigments, carotenoids, and sucrose in leaves. Application of Co and Mo doses also increased biological nitrogen fixation by increasing the concentration of allantoic acid, nitrate, ammonia, and amino acids in leaves. The concentration of total amino acids corresponded to most of the nitrogen compounds (on average 50%), followed by the concentrations of nitrate (35%), ammonia (11%), allantoic acid (7%), and allantoin (0.2%). Application of 4?mL kg?1 increased the production of total amino acids compared with the control treatment. Pod yield was not affected by the Co and Mo doses; however, treatment of peanut seeds with 4?mL kg?1 was the most viable alternative for increased production of primary metabolism compounds, nitrogen forms, and photosynthetic pigments in peanut plants. This study provides important information regarding the role of Co and Mo in the biological nitrogen fixation of peanut plants. Future experiments should be conducted using a dose of 4?mL kg?1 with different genotypes to verify the potential for increasing peanut yield. 相似文献
165.
Julia Ramos-Miranda Rodolfo del Río-Rodríguez Domingo Flores-Hernández Ramón Isaac Rojas-González Mónica Gómez-Solano Ana Delia Cu-Escamilla Francisco Gómez-Criollo Atahualpa Sosa-López Yassir Eden Torres-Rojas Paloma Juárez-Camargo 《Fisheries Science》2017,83(5):699-714
The reproduction of Holothuria floridana in Campeche bay, southern Gulf of Mexico, was investigated over a period of 12 months by macroscopic and histological examination of the gonad and gametogenesis. A total of 1938 specimens were collected. Their body gutted weight and body gutted length ranged from 15 to 225 g and 5 to 21 cm, respectively. Percentage of the gonad weight to the gutted body weight (gonad index, GI) increased steadily from December to April, rapidly declined in May, and remained low during the following months. GI displayed a negative correlation with temperature of the habitat and no correlation with salinity. The gonad maturity scale with five stages was developed from macroscopic and microscopic observations; I, recovery; II, growing; III, early mature; IV, mature and V, spent. Stages III to V were observed all around the year, suggesting that this species displays continuous reproduction with two peaks of spawning events; from March to April and in September. The presence of viscera regurgitated individuals caused high variability in GI. The sex-ratio varied from 1:1 (December 2013 to June 2014), to 1.37:1 (November 2013); we suggest that this may be the consequence of unintentional selective fishing. The body length and body weight at the first maturity were calculated to be 13.4 cm and 87.0 g, respectively. For resource management it will be necessary to address some reference points like harvest season and avoidance of catches shorter than length at first maturity. 相似文献
166.
Tom Bins Rodolfo Oliveira Leal Marina DomínguezRuiz Rodolfo Elvas De Carvalho Nina Fernandes Rodrigues Claire Dally JeanCharles Husson Kevin Le Boedec Juan Hernandez 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2022,36(2):515
BackgroundThe relationships among gastric lymphoid follicular hyperplasia (GLFH), Helicobacter‐like organisms (HLOs), and clinical signs have not been established in dogs.ObjectivesTo evaluate the epidemiologic, clinical, endoscopic, and histopathologic findings associated with GLFH in dogs, and determine the association of GLFH with HLOs and the French Bulldog (FB) breed.AnimalsTwo hundred eighty‐eight dogs that underwent gastroscopy between 2013 and 2016.MethodsRetrospective, cross‐sectional study. Gastric biopsy samples were reviewed and scored for inflammation and HLOs. Dogs were divided into 3 groups: group 1 (63 FBs), group 2 (45 non‐FB brachycephalic dogs), and group 3 (180 nonbrachycephalic dogs). Variables were evaluated for their association with GLFH.ResultsUnivariate analysis determined that intact males, young age, vomiting, gastroscopic findings (discoloration, hemorrhage, and ulcers), and histopathologic findings (gastric lamina propria lymphocytic infiltration and HLO score) were associated with GLFH (P ≤ .03). In the multivariate analysis, GLFH was associated with the HLO score (odds ratio [OR] > 5 for HLO scores 1‐2 and >15 for HLO score of 3; P < .001), with vomiting (OR > 4; P = .01) but not with FB breed (P = .76) and age (P = .1). The HLO score was associated with younger age (P < .001).Conclusion and Clinical ImportanceThe HLO score was associated with a high GLFH score. Vomiting was associated with GLFH. Helicobacter‐like organisms are highly prevalent in young dogs and GLFH is indirectly associated with this factor. Clinical relevance of the identification of GLFH and HLO remains to be determined. 相似文献
167.
With the soaring cost and scarcity at times of inorganic fertilizers in the country, there is a need to find alternatives
to inorganic fertilizers by making use of indigenous materials such as leaves of leguminous plants, mudpress, and so enhance
growth and development of crops. Application of ‘ipil-ipil’ (Leucaena leucocephala) green manure supplemented with inorganic
P and K caused vigorous growth of cassava (Manihot esculenta). Application of ipil-ipil biomass at the rate of 7.23 t ha−1
resulted in high yield and better values of yield components of cassava. However, due to high expenses incurred in hauling,
transport and cost of the green manure materials, their use is likely to be more economical and feasible only if ipil-ipil
is readily available in the farm. With taro (Colocasia esculenta), combined application of ipil-ipil green manure and inorganic
P and K promoted vigorous stand and higher yield of the crop. Significantly larger corms were formed resulting in higher total
corm yields and marketability than the control (untreated) and those treated only with 60–39.6–74.7 kg ha−1 N, P, and K from
inorganic fertilizer. Increasing the rate of inorganic N applied to plants (90–36.9–74.7 kg ha−1 N, P, K) during a third cropping,
gave comparable yield to treatment involving 7.23 t ha−1 ipil-ipil supplemented with inorganic P and K. Despite the relatively
higher gross income obtained from organic and inorganic treatment combinations, slightly lower net income was obtained compared
with inorganic fertilizer-applied plants due to higher production expenses incurred with the former treatments.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
168.
First evidence of resistance to pyrethroid insecticides in Italian Aedes albopictus populations 26 years after invasion 下载免费PDF全文
Verena Pichler Romeo Bellini Rodolfo Veronesi Daniele Arnoldi Annapaola Rizzoli Riccardo Paolo Lia Domenico Otranto Fabrizio Montarsi Sara Carlin Marco Ballardini Elisa Antognini Marco Salvemini Emanuele Brianti Gabriella Gaglio Mattia Manica Pietro Cobre Paola Serini Enkelejda Velo John Vontas Ilias Kioulos Joao Pinto Alessandra della Torre Beniamino Caputo 《Pest management science》2018,74(6):1319-1327
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Perla Osorio‐Díaz Alondra Aguilar‐Sandoval Edith Agama‐Acevedo Rodolfo Rendn‐Villalobos Juscelino Tovar Luis A. Bello‐Prez 《Cereal Chemistry》2008,85(3):339-343
In search of a way to improve the nutritional profile of noodles, we prepared them with various mixtures of durum wheat flour and isolated plantain starch, and tested their proximal composition. Cooked noodles were assessed for in vitro starch digestibility, indigestible fraction content, and predicted glycemic index. The protein content declined with the addition of plantain starch. Both total starch (TS) level and the content of starch available for digestible enzymes (AS) decreased as the plantain starch level increased, a pattern that may be related to increased starch lixiviation during cooking of noodles containing plantain starch. There was an inverse pattern for resistant starch (RS). RS content in control (durum wheat flour) noodles was ≈50% lower than in the samples containing plantain starch. The soluble indigestible fraction (SIF) content in all samples was higher than the insoluble counterpart (IIF). The total indigestible fraction varied according to the wheat substitution level. Although the hydrolysis index (HI) and predicted glycemic index (pGI) of plantain starch noodles were moderate and decreased as the plantain starch proportion rose. These composite noodles exhibited higher indices than the control sample, a phenomenon that may also be dependent on the product physical structure. Results indicate that in spite of the increased starch digestion rate, plantain starch noodles are a better source of indigestible carbohydrates than pure wheat starch pasta. This might have dietetic applications. 相似文献