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Melamine-Based Microporous Organic Framework Thin Films on an Alumina Membrane for High-Flux Organic Solvent Nanofiltration
No full textMicroporous polymer frameworks have attracted considerable attention to make novel separation layers owing to their highly porous structure, high permeability, and excellent molecular separation. This study concerns the fabrication and properties of thin melamine-based microporous polymer networks with a layer thickness of around 400 nm, supported on an α-alumina support and their potential use in organic solvent nanofiltration. The modified membranes show excellent solvent purification performances, such as n-heptane permeability as high as 9.2 L m−2 h−1 bar −1 in combination with a very high rejection of approximately 99 % for organic dyes with molecular weight of ≥457 Da. These values are higher than for the majority of the state-of-the-art membranes. The membranes further exhibit outstanding long-term operation stability. This work significantly expands the possibilities of using ceramic membranes in organic solvent nanofiltration.</p
Nutrient flows and intensification options for smallholder farmers of the Lao uplands
No full textSouth East Asia's agricultural landscape is rapidly transitioning from subsistence to intensive and market-oriented production, often with negative impacts on soil fertility. Ensuring that this transition is conducted in a sustainable way is critical, especially for the poorest who rely exclusively on natural resources that are of limited quality and quantity. This study aims to evaluate sustainable intensification options for smallholder ethnic minority farmers of the Lao uplands. Following a systematic selection of case study crop-livestock farms with different degrees of diversification and market orientation, we adopted a detailed nutrient flow approach to quantify nitrogen (N) and phosphorus (P) balances at farm level using a whole farm modelling tool. This was then used to simulate alternative sustainable intensification options relative to the baseline and their impact on farm performance and N and P cycling. Irrespective of the intensification level, nutrient balances were negative on all farms, with net nutrient removal between −34 and −130 kg N ha−1y−1 and between −9 and −20 kg P ha−1y−1. The positive effect of the sustainable intensification options on selected system performance variables was up to 15 times higher when its baseline value was low, i.e. when potential for improvement was high. Compared to the baseline (rice and maize monocropping systems), fallow plots during the dry season and low level of residues recycling, all intensification options increased land productivity and N balance by at least 12% on each farm, whereas the P balances were negatively impacted. The positive effects on the N balances might not be sufficient to reverse nutrient depletion, and additional nutrient inputs would be necessary. Four management principles are key to ensure a smooth transition from subsistence to intensive production: no residue burning, stay diverse, integrate livestock and use small amounts of P mineral fertilizer. If combined with efficient and integrative agricultural extension, seed systems and market development, these basic principles could be the key success factor for a sustainable development of the Lao uplands.</p
Physicochemical properties of spray-dried model infant milk formula powders: Influence of whey protein-to-casein ratio
No full textThe effect of whey protein-to-casein ratio (60:40, 50:50 and 40:60) on the physicochemical properties of model infant milk formula (IMF) wet-mixes and powders prepared therefrom was studied. A lower whey protein-to-casein ratio lowered the zeta potential and apparent viscosity of wet-mixes and increased the particle size after evaporation. Particle size and water activity of powders decreased with decreasing whey protein-to-casein ratio. Glass transition temperature, crystallinity, surface free fat content and solubility of the powders were similar and unaffected by protein composition. Surface composition of powders was substantially different from their bulk composition irrespective of the protein ratios, with fat representing more of the powders surface (∼42–44%) followed by protein (∼30–32%) and lactose (∼24–26%). Overall, IMF powders can be prepared by varying the whey protein-to-casein ratio without affecting the physicochemical properties of the feed and the spray-dried powders.</p
Heatwaves, droughts, and fires: Exploring compound and cascading dry hazards at the pan-European scale
Full text linkCompound and cascading natural hazards usually cause more severe impacts than any of the single hazard events alone. Despite the significant impacts of compound hazards, many studies have only focused on single hazards. The aim of this paper is to investigate spatio-temporal patterns of compound and cascading hazards using historical data for dry hazards, namely heatwaves, droughts, and fires across Europe. We streamlined a simple methodology to explore the occurrence of such events on a daily basis. Droughts in soil moisture were analyzed using time series of a threshold-based index, obtained from the LISFLOOD hydrological model forced with observations. Heatwave and fire events were analyzed using the ERA5-based temperature and Fire Weather Index datasets. The data used in this study relates to the summer seasons from 1990 to 2018. Our results show that joint dry hazard occurrences were identified in west, central, and east Europe, and with a lower frequency in southern Europe and eastern Scandinavia. Drought plays a substantial role in the occurrence of the compound and cascading events of dry hazards, especially in southern Europe as it drives duration of cascading events. Moreover, drought is the most frequent hazard-precursor in cascading events, followed by compound drought-fire events. Changing the definition of a cascading dry hazard by increasing the number of days without a hazard from 1 to 21 within the event (inter-event criterion), lowers as expected, the maximum number of cascading events from 94 to 42, and extends the maximum average duration of cascading events from 38 to 86 days. We had to use proxy observed data to determine the three selected dry hazards because long time series of reported dry hazards do not exist. A complete and specific database with reported hazards is a prerequisite to obtain a more comprehensive insight into compound and cascading dry hazards.</p
Food preferences and intake in a population of Dutch individuals with self-reported smell loss: An online survey
No full textOlfaction plays a major role in food intake regulation. Losing the sense of smell might therefore affect eating behavior. This study investigated food preferences and intake in individuals suffering from self-reported smell loss with an online survey. Members of the Dutch Anosmia Foundation (DAF) performed the Macronutrient and Taste Preference Ranking Task (n = 71) to measure preference for foods high in fat, carbohydrates or protein and low energy foods, and for sweet and savory tastes. To assess dietary intake, adherence to the Dutch Dietary Guidelines for consumption of vegetables, fruit, fiber, fish, saturated fat, trans fatty acids, salt and alcohol was measured (n = 105). Results of the DAF participants were compared to local cohort groups. Both the control and DAF participants showed the lowest preference for carbohydrate-rich foods and highest preference for low-energy foods. Participants suffering from congenital smell loss showed an aberrant pattern, with a higher preference for fat. The total adherence score to the Dutch Dietary Guidelines was similar for the control and DAF group, but adherence scores for fiber, trans fatty acids and alcohol were lower in DAF participants. Overall, no major significant differences in food preferences and intake were found for participants who lost their sense of smell during life. Participants suffering from congenital smell loss did show changes in food preferences, suggesting they are potentially more taste-oriented during eating. Together these results show the importance of tailored advice on dietary intake for this patient group.</p
The impact of Russian sanctions on the return of agricultural commodity futures in the EU
No full textDuring the last conflict between Russia and the Ukraine in 2014, the EU imposed various multilateral sanctions on Russia. As a response, Russia retaliated these measures by banning the agricultural imports from the EU. This study explores whether the retaliation sanctions taken by Russia were already expected by investors or came as a complete surprise. For this purpose, I compare the impact of sanction-related news before and after the official announcement of these sanctions by president Putin in August 2014 on the weekly return of a number of agricultural commodity futures traded at two European commodity exchanges. A newly created indicator on sanction-related news is used that is based on the number of articles that have been published in the major European newspapers containing information about the import ban. The main findings clearly point out that before the imposition of the boycott it was already partly anticipated. The publication of sanction-related news caused a significant drop in the futures return of a number of banned agricultural commodities in the weeks prior to the formal announcement.</p
A bittersweet meal: The impact of sugar solutions and honeydew on the fitness of two predatory gall midges
No full textAdult survival and reproduction of many species of arthropod natural enemies depend exclusively on sugar-rich food such as honeydew. Here, we tested the impact of two types of honeydew as well as several sugars at different concentrations (10%, 25%, 50%) on the longevity and reproduction of two life-history omnivores. On the one hand, the aphid-feeding gall midge Aphidoletes aphidimyza (Rondani) and on the other hand the gall midge Feltiella acarisuga (Vallot) (Diptera: Cecidomiydae), a predator that can feed on many spider-mite species during the juvenile stage. Compared to a water control, females provided with the commercial sugar Biogluc® at a 10% concentration showed an increase in longevity by a factor of 3.6 for A. aphidimyza and 4.7 for F. acarisuga, respectively, whereas Biogluc® at a 50% concentration significantly reduced longevity in both species. Sucrose solutions had a positive, yet less pronounced effect. Feeding on Biogluc® or sucrose (all concentrations) raised the number of oocytes for A. aphidimyza and F. acarisuga by a factor 2.2–2.6 and 2.0–2.5, respectively. The highest realized fecundity during 72 h was recorded for A. aphidimiza females supplied with 50% Biogluc® (increase by 5.1) or in the case of F. acarisuga the strongest effect was observed with 10% Biogluc® (increase by 3.5). For the rest of the Biogluc® and sucrose solutions the effects were less pronounced. In contrast, aphid honeydew did not raise female longevity, nor the number of oocytes or eggs laid. Our results imply that sugar solutions at modest concentration (10%) are best suited for use to support these gall midges in the field as well as in mass rearing. Finally, given the positive association between the number of oocytes and the number of eggs laid for both species, we propose the use of the former as a proxy to assess the fertility for both species to simplify the procedures for quality assessments currently employed by the biocontrol industry.</p
Spatial quantification to examine the effectiveness of payments for ecosystem services: A case study of Costa Rica's Pago de Servicios Ambientales
No full textPayments for ecosystem services (PES) have been developed as a policy instrument to help safeguard the contributions of ecosystems to human well-being. A critical measure of a programme's effectiveness is whether it is generating an additional supply of ecosystem services (ES). So far, there has been limited analysis of PES programmes based on the actual supply of ES. In line with ecosystem accounting principles, we spatially quantified three ES recognised by Costa Rica's Pago de Servicios Ambientales (PSA) programme: carbon storage, soil erosion control and habitat suitability for biodiversity as a cultural ES. We used the machine learning algorithm random forest to model carbon storage, the Revised Universal Soil Loss Equation (RUSLE) to model soil erosion control and Maxent to model habitat suitability. The additional effect of the PSA programme on carbon storage was examined using linear regression. Forested land was found to store 235.3 Mt of carbon, control for 148 Mt yr−1 of soil erosion and contain 762,891 ha of suitable habitat for three iconic but threatened species. PSA areas enrolled in the programme in both 2011 and 2013 were found to store an additional 9 tonC ha−1 on average. As well as enabling a direct quantification of additionality, spatial distribution analysis can help administrators target high-value areas, confirm the conditional supply of ES and support the monetary valuation of ES. Ultimately, this can help improve the social efficiency of payments by enabling a comparison of societal costs and benefits.</p
Using product popularity to stimulate choice for light products in supermarkets: An examination in virtual reality
No full textWith the use of virtual reality, this study investigates the potential for popularity cues to stimulate consumers to choose healthier products (versus regular products) within product categories in a supermarket context. Popularity may increase perceived product quality and perceived certainty about that quality. Healthier alternatives (i.e., light products) within a category often have a taste disadvantage compared to regular counterparts as a result of their trimmed down nutrient profiles (low in fat, sugar or salt). Because consumers are more uncertain about the taste of these light products, a popularity cue may have a larger effect on product choice for these options than on the choice for regular products. This hypothesis is tested in an experiment using virtual reality to realistically display a supermarket context. In the main experiment, a sample of 300 consumers was asked to shop for specific groceries, using existing brands and products. The results demonstrate that consumers are more likely to choose light products when these are combined with a popularity cue. In contrast, the popularity cue did not affect choice for the regular alternatives. These results have important implications for research, and for public-policy makers and food retailers that aim to stimulate healthful consumption.</p
Effect of heat treatment on bacteriostatic activity and protein profile of bovine whey proteins
No full textBovine milk shows bacteriostatic activity mainly due to the presence of antibacterial proteins, like lactoferrin, lactoperoxidase and immunoglobulins. Heat treatment is applied to kill bacteria and thereby extend shelf life of dairy products. Such heat treatment may, however, impair the activity of native antibacterial proteins in milk. The aim of this study was to investigate bacteriostatic capacity and retention of antibacterial proteins in unheated and heated bovine milk. Skim milk samples were heated at 65 °C, 70 °C, 75 °C, 80 °C and 85 °C, for 30 min. Whey was isolated from the heat-treated skim milk and the bacteriostatic capacity of this whey was tested against Streptococcus thermophilus, Escherichia coli, Lactococcus lactis and Pseudomonas fluorescens. The proteomic profile of native whey was determined using LC-MS/MS-based proteomics. Results showed that the bacteriostatic activity of whey negatively correlated with intensity of heat treatment, which was also reflected in the reduced level of native antibacterial proteins. There is a significant difference between milk samples treated for 30 min at <75 °C and milk samples treated at ≥75 °C in both bacteriostatic capacity and native antibacterial proteins. Growth rates of Streptococcus thermophilus, Lactococcus lactis and Pseudomonas fluorescens were negatively correlated with retention of lactoferrin and lactoperoxidase. In conclusion, our study shows that the bacteriostatic capacity of whey decreases with increasing heating intensity, which is strongly correlated with the denaturation of antibacterial proteins. Bacteriostatic activity can be a biomarker for loss of function of antibacterial proteins, and can thereby be used as an indicator for the extent of heat processing of dairy products including antibacterial proteins in a mild heat treatment.</p