Ameliorating Effect of Chloride on Nitrite Toxicity to Freshwater Invertebrates with Different Physiology: a Comparative Study Between Amphipods and Planarians

High nitrite concentrations in freshwater ecosystems may cause toxicity to aquatic animals. These living organisms can take nitrite up from water through their chloride cells, subsequently suffering oxidation of their respiratory pigments (hemoglobin, hemocyanin). Because NO2¿ and Cl¿ ions compete for the same active transport site, elevated chloride concentrations in the aquatic environment have the potential of reducing nitrite toxicity. Although this ameliorating effect is well documented in fish, it has been largely ignored in wild freshwater invertebrates. The aim of this study was to compare the ameliorating effect of chloride on nitrite toxicity to two species of freshwater invertebrates differing in physiology: Eulimnogammarus toletanus (amphipods) and Polycelis felina (planarians). The former species presents gills (with chloride cells) and respiratory pigments, whereas in the latter species these are absent. Test animals were exposed in triplicate for 168 h to a single nitrite concentration (5 ppm NO2-N for E. toletanus and 100 ppm NO2-N for P. felina) at four different environmental chloride concentrations (27.8, 58.3, 85.3, and 108.0 ppm Cl¿). The number of dead animals and the number of affected individuals (i.e., number of dead plus inactive invertebrates) were monitored every day. LT50 (lethal time) and ET50 (effective time) were estimated for each species and each chloride concentration. LT50 and ET50 values increased with increases in the environmental chloride concentration, mainly in amphipods. Results clearly show that the ameliorating effect of chloride on nitrite toxicity was more significant in amphipods than in planarians, likely because of the absence of gills (with chloride cells) and respiratory pigments in P. felina. Additionally, this comparative study indicates that the ecological risk assessment of nitrite in freshwater ecosystems should take into account not only the most sensitive and key species in the communities, but also chloride levels in the aquatic environmen

Effect of Pruning Severity on Yield, Drying Time and Wages in Flame Seedless Dry-on-vine and Traditional Raisin Production Systems in Argentina

Raisin grapes are potentially more profitable than wine grapes in San Juan, Argentina, although the traditional system of grape drying requires an extensive use of costly labour. Production costs might be reduced by adopting the dry-on-vine (DOV) raisin-making system, but the feasibility of DOV in Argentina has not been assessed, and neither have the costs and pruning schemes. Thus we determined drying time and yields, estimated wages per hectare, and determined the influence of pruning severity on Flame Seedless raisin grapes. A completely random design with six treatments and six replicates was used in the 2013 to 2016 seasons. The treatments comprised differences in the nodes per cane, nodes per vine,distribution of nodes, and sugar content. Descriptive statistics and variance analysis were calculated for fresh fruit weight, dry fruit weight, drying ratio and drying time. The leaf area and its relationship with dried fruit weight also were calculated. These data were processed with the Infostat program. The DOV system demands between 11 and 31 additional days during the drying period and reduces labour costs by between 38% and 64% compared to the traditional system. Long pruning with the same load of buds is better. Furthermore, the DOV system is not associated with a lower production and thus appears to be a financially sustainable alternative to traditional production systems for Flame Seedless raisin grape producers in Argentina

Assessment of clogging effects on lateral hydraulics: proposing a monitoring and detection protocol

International audienceAgeing of drip irrigation systems due to clogging of emitters is considered the largest maintenance problem in microirrigation and this problem is enhanced in subsurface irrigation systems. Whatever the source of the clogging problem, a methodology for early detection of clogging in the field can be useful in decision-making about deploying cleaning processes (flushing or injection of chemicals) and avoiding replacement of laterals. This work presents a methodology for simulating clogging conditions able to reproduce the effects of clogging on pressure profiles, head loss, and emitters flow rate distribution along a single levelled lateral with constant inlet pressure. This methodology was validated by several experiments conducted under controlled conditions of clogging induced by changes in the flow rate of emitters. The effects of clogging intensity and position on hydraulic parameters of a single lateral were analysed in detail and aspects relating to pressure, head loss, and flow rate measurements were discussed. For a given lateral set-up, it is possible to draw a chart relating flow rate and head loss for various levels and positions of clogging. Assuming that measurements of head loss and flow rate are available, this diagram enables immediate estimation of the level and location of clogging

Reactions with light exotic nuclei

CNR*13 - Fourth International Workshop on Compound Nuclear Reactions and RelatedExperimental cross sections for the 6He+120Sn are analysed. Elastic scattering angular distributions and alpha particle production cross sections have been measured and are compared with the total reaction cross section

Pickering emulsions stabilized with curcumin-based solid dispersion particles as mayonnaise-like food sauce alternatives

Pickering emulsions, which are emulsions stabilized by colloidal particles, are being increasingly positioned as novel strategies to develop innovative food product solutions. In this context, the present work aims to develop Pickering emulsions stabilized by natural-based curcuminloaded particles produced by the solid dispersion technique as promising mayonnaise-like food sauce alternatives. Two particle formulations (KC1 and KC2) were produced using k-carrageenan as the matrix material and different curcumin contents, then employed in the preparation of three Pickering emulsion formulations comprising different oil fractions (') and particle concentrations (KC1 ' 0.4 (4.7%), KC2 ' 0.4 (4.7%) and KC2 ' 0.6 (4.0%)). The creaming index tests accompanied by the optical microscopy analysis evidenced the good stability of the developed products for the tested period of 28 days. The final products were tested concerning color attributes, pH, oxidative stability, textural, and nutritional composition, and compared with two commercial mayonnaises (traditional and light products). Overall, the produced emulsions were characterized by a bright yellow color (an appealing attribute for consumers), an acidic pH (similar to mayonnaise), and a considerably improved oxidative stability, implying a foreseeable longer shelf life. The sauce KC1 ' 0.4 (4.7%) showed a similar texture to the light commercial mayonnaise, being a promising alternative to conventional sauces, holding a low-fat content and potentially added benefits due to the curcumin and virgin olive oil intrinsic properties.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) and FEDER under Programme PT2020 for financial support to CIMO (UIDB/00690/2020) and LSRE-LCM (UIDB/50020/2020). Promove program of the “la Caixa” Foundation and BPI. National funding by FCT, P.I., through the institutional scientific employment program-contract for Arantzazu Santamaria-Echart, Nuno Rodrigues, Márcio Carocho, and Lillian Barros. FCT for the Research grant SFRH/BD/147326/2019 of Stephany C. de Rezende.info:eu-repo/semantics/publishedVersio

Avaliação da presença de coliformes, bolores e leveduras em amostras de mel orgânico de abelhas africanizadas das ilhas do alto rio Paraná.

O presente trabalho foi desenvolvido para caracterizar a microbiota do mel produzido nas ilhas Floresta e Laranjeira do alto rio Paraná, na região de Porto Brasílio, Paraná (PR). O mel foi coletado diretamente das melgueiras das colônias avaliadas, em três apiários distribuídos nas ilhas Floresta e Laranjeira. O período de coleta das amostras de mel foi de novembro de 2005 a fevereiro de 2006, perfazendo o total de 24 amostras de mel orgânico produzido por abelhas Apis mellifera africanizadas. Seguindo o método das normas internacionais da Compendium of Methods for the Microbiology Examination of Foods, os parâmetros analisados foram: presença de coliformes a 35°C e 45°C e quantificação de bolores e leveduras. Verificou-se que todas as amostras apresentaram-se em conformidade com o Regulamento Técnico MERCOSUL de Identidade e Qualidade do Mel (MERCOSUL/GMC/RES no 15/94). As amostras analisadas indicaram excelente qualidade microbiológica para o mel orgânico

Efeitos da densidade de população de plantas na cultura de couve-flor (Brassica oleracea L. var. botrytis)

An experiment was carried out to study the effects of the following population densities cauliflowers (plants per ha): 20,833 (0.60 m x 0.80 m), 25,641 (0.60 m x 0.65 m), ....37.037 (0.60 m x 0.45 m) , 55.555 (.0.60 m x 0.30 m), and 111,111 (0,60 m x 0,15 m) ; variety Snow ball. It was concluded that the effects of plant population density are greater on curd quality (weight and size) than on production per ha. The best plant population density to produce cauliflowers curd for Brazil market is from 20,000 to 25,000 plants/ha while for mini-curd is above 55,000 plants/ha.O experimento foi instalado na área experimental do Setor de Horticultura da ESALQ. (Piracicaba, SP), em um Latossol Roxo série "Luiz de Queiroz", em março de 1977, considerando as seguintes densidades de população: 20.833 plantas/ha (0,60 m x 0,80m), .. 25.641 plantas/ha (0,60 m x 0,65 m), 37.037 plantas/ha (..0.,60 m x 0,45 ml, 55.550 plantas/ha (,06Q m x 0,30 ,) e 111.111 plantas/ ha (0,60 m x 0,15 m). A partir dos resultados obtidos e para as condições do experimento concluiu-se que a densidade de população sobre a produção de couve-flor afeta mais a qualidade da cabeça (peso e tamanho), enquanto que o rendimento por área é pouco afetado. Para as condições do nosso mercado, a densidade ótima deve estar entre 20.000 a 25.000 plantas por ha e para a produção de mini-couve-flor mais de 55.000 plantas por ha, paraocultivar Bola de Neve