Impact of silicon-based quantum dots on the antioxidative system in white muscle of Carassius auratus gibelio

Silicon-based quantum dots were intraperitoneally injected in individuals of Carassius auratus gibelio. Their effects on white muscle were investigated by following their distribution and impact on the antioxidative system. The GSH level significantly increased after 1 and 3?days of exposure by, respectively, 85.3 and 25.4%. Seven days later, GSH levels were similar to control concentrations. MDA concentration rose after three days by 46.9% and remained at the same level after 7?days. Protein thiol levels significantly decreased by 6.7 and 8.1% after 3 and 7?days, whereas advanced oxidation protein products increased by 12.7, respectively, 28.1% in the same time intervals. The protein reactive carbonyl groups were raised only after the first day of exposure and returned to the control level later on. SOD specific activity increased up to 48% after 7?days, while CAT activity increased by 328, 176, and 26% after 1, 3, and 7?days of treatment. GST specific activity was up-regulated by 87, 18, and 9%, while GR activity increased by 68, 34, and 9%. G6PD activity was up-regulated by 12, 22, and 50%, whereas GPx activity raised by 75 and 109% compared to control after, respectively, 1, 3, and 7?days. Our results suggest that oxidative stress induced by silicon-based quantum dots was not strong enough to cause permanent damage in the white muscle of crucian carp.     

Yield and Price Forecasting for Stochastic Crop Decision Planning

The primary objective of this paper is to develop yield and price forecasting models employed in informed crop decision planning—a key aspect of effective farm management. For yearly yield prediction, we introduce a weather-based regression model with time-dependent varying coefficients. In order to allow for within-year climate variations, we predict yearly crop yield using weekly temperature and rainfall summaries resulting in a large number of correlated predictors. To overcome this difficulty, we reduce the space of predictors to a small number of uncorrelated predictors using Functional Principal Component Analysis (FPCA). For detailed price forecasting, we develop a futures-based model for long-range cash price prediction. In this model, the cash price is predicted as a sum of the nearby settlement futures price and the predicted commodity basis. We predict the one-year commodity basis as a mixture of historical basis data using a functional model-based approach. In both forecasting models, we estimate approximate prediction confidence intervals that are further integrated in a decision planning model. We applied our methods to corn yield and price forecasting for Hancock County in Illinois. Our forecasting results are more accurate in comparison to predictions based on existing methods. The methods introduced in this paper generally apply to other locations in the US and other crop types. The supplemental materials for this article are available online.     

Relative sensitivity of different soil biological properties to zinc

This study investigated the responses to Zn of selected enzymatic activities, potential nitrification and microbial activity in a soil contaminated with Zn at concentrations ranging from 74 to 3490 mg kg⁻¹. The main aims of the study were to evaluate different models for EC₅₀ estimation and to compare the relative sensitivity to Zn of the different biological properties studied. The EC₅₀ for each property was calculated using three different models, namely a logistic dose response model, and a full and a partial inhibition model based on Michaelis-Menten kinetics. Both total (aqua regia extractable) and labile (CaCl₂ extractable) Zn content were assessed and employed for application of the models. A response to increasing Zn concentrations was observed for most of the biological properties except for fluorescein diacetate hydrolysis activity (FDA) and acid phosphatase activity. Among the three models tested, the logistic model had the widest applicability and generally gave the best results in terms of EC₅₀ estimation and R² fit. Among the two kinetics models tested, the partial inhibition model was applicable only in a few cases, but in these cases results are generally better than for the full inhibition model. The utilization of either total or labile Zn data did not significantly affect the outcomes of the models. The sensitivity of the biological properties to Zn was ranked according to the models as follows: nitrate reductase > potential nitrification > β-galactosidase > dehydrogenase > phenol oxidase = urease = arylsulphatase. These ranking results were generally in accordance with evidence provided by other researchers, thus showing that the relative sensitivity of these properties, especially the most sensitive ones, is generally constant among different soil types. The relevance of this finding for soil ecological risk assessment is discussed.     

Universal criteria for species conservation priorities? Findings from a survey of public views across Europe

Decisions on biodiversity management and conservation are increasingly based on indicators. These imply, explicitly or implicitly, a number of criteria such as nativeness, rarity, endangeredness and (economic) value. We investigated to which degree such criteria matter to members of the general public and conducted a survey in eight sites across Europe (n = 2378). We explored the relationships between perceived desirability of a species’ population increase and six species-related attributes, including previous population change, rarity, vulnerability, harmfulness, value, attractiveness, and nativeness.For all three species types investigated, previous population change, followed by perceived harmfulness and value, had the strongest relationship with desirability of future increase. Perceived nativeness played only a minor role in informing a species’ desirability. A strong relationship between previous change and desirability of future increase could also be found in a number of additional species and six different habitat types, suggesting that previous change is a key criterion that the general public draws on to inform their attitudes towards biodiversity management.We compare the roles of such criteria for the general public to those used in the scientific and political discourse, and draw conclusions for the use of indicators in the conservation debate, arguing that biodiversity management that is strongly focused on nativeness might fall short of the interests of the citizenship, whereas other criteria, such as population trends, harmfulness and role and value of a species in the ecosystem strongly resonate with the views of the general public.