Fast determination of biogenic amines in beverages by a core-shell particle column

A fast and reliable HPLC method for the determination of 11 biogenic amines in beverages has been performed. After pre-column derivatization with dansyl-chloride a Kinetex C18 core–shell particle column (100 mm × 4.6 mm, 2.6 μm particle size) has been employed and the biogenic amines were identified and quantified in a total run time of 13 min with ultraviolet (UV) or fluorescence detection (FLD). Chromatographic conditions such as column temperature (kept at 50 °C), gradient elution and flow rate have been optimized and the method has been tested on red wine and fruit nectar. The proposed method is enhanced in terms of reduced analysis time and eluent consumption with respect of classical HPLC method as to be comparable to UHPLC methods. Green and cost-effective, this method can be used as a quality-control tool for routine quantitative analysis of biogenic amines in beverages for the average laboratory

Tracing hydrological connectivity

Understanding how different structural and functional elements of a catchment connect together to generate spatially and temporally variable fluxes of water, sediment and nutrients is fundamental for gaining a holistic comprehension of catchments’ hydrological behaviour. However, advancements in hydrological connectivity research still suffer from technical limitations inherent to the (i) investigation of connectivity at large scales (e.g. catchment scale), (ii) identification of intra-catchment heterogeneous landscape structures and connectivity pathways, and (iii) characterisation of the hydrological processes occurring at small scale around transition zones (e.g. the riparian zone). In this thesis, some of these challenging aspects are addressed by investigating hydrological connectivity at different spatio-temporal scales through two innovative, multidisciplinary approaches – namely terrestrial diatoms (unicellular, eukaryotic algae) and ground-based thermal infrared imagery (TIR). This thesis is wired around five studies that have explored the potential for these innovative avenues to overcome the prevailing status quo in hydrological connectivity research. Chapter 2 focuses on terrestrial diatoms’ ecological behaviour and sensitivity to environmental factors. Understanding the physiographic controls on terrestrial diatom communities is fundamental for advancing their employment as a tracer of hydrological connectivity at the catchment scale. Chapter 3 explores the potential for ground-based TIR imagery to provide instantaneous mapping of stream water mixing and mixing dynamics at confluence-scale. Cross-sectional variability in surface temperature observed through TIR imagery is found to reflect the in−stream variability of temperature and chemistry. Chapter 4 reports a technical study on the application of ground-based TIR imagery for mapping surface-saturation dynamics in the riparian zone. The results of a repeated mapping of surface saturation through ground-based TIR imagery are presented in Chapter 5. In this chapter, the seasonal dynamics of surface saturation in seven different riparian areas are characterised. The development of surface-saturation in the different areas is found to be influenced by heterogeneous catchment features such as riparian areas elevation, local riparian morphology (i.e. width of the riparian areas) and the presence or absence of groundwater exfiltration points. These heterogeneous catchment features also influence the shape of the surface-saturation vs. outlet baseflow relationship. In Chapter 6, the previously explored riparian surface-saturation dynamics are related to streamflow contributions from the corresponding stream reaches. The observed relationships provide information on the degree of hillslope-riparian-stream connectivity of different portions of the catchment. Overall, the studies presented in this thesis show how novel, multidisciplinary approaches and techniques can provide new information on hydrological connectivity across different spatial and temporal scales of investigation. An improved understanding of how connectivity is established within the catchment will eventually lead to a better management of our hydrological resources, increasingly put under pressure by climate change and anthropogenic activities

The future of the Mediterranean agri-food systems: trends and perspectives from a Delphi survey

The Mediterranean region is widely acknowledged as one of the most exposed in the world to the effects of climate change, water scarcity, biodiversity loss and land degradation, coupled with a nutrition transition of its populations. In such a context, to explore the evolution of the region is of both political and theoretical interest. This study presents the result of a scenario-building exercise, based on a Delphi method – an interactive forecasting technique – relying upon about 60 practitioners, experts and academics representing 19 Mediterranean countries and a wide range of disciplines and expertise. The present article has three main purposes. First, to identify the main challenges, trends and driving forces that influence the agri-food systems in the Mediterranean over a short (2020) and medium (2030) term. Second, to discuss the alternative policy responses to the challenges that the region will face in terms of water resource management, farming systems and agri-food value chains in terms of desirability and feasibility. Thirdly, to provide informed, evidence-based recommendations that might help different stakeholders to take action in the region’s agri-food sector. Based on this Delphi’s results, the study suggests that the gap between the countries in the South and the North of the Mediterranean in terms of challenges posed in water management, farming systems and the agri-food value chain is expected to grow. Experts agree that climate change is going to play a key role in the future of both sides of the Mediterranean, but with a differential impact in the sub-two regions. Nutrition-related challenges will exert a growing pressure especially in the Southern Mediterranean countries. A set of desirable and feasible policy option for addressing the Mediterranean food-related challenges are discussed

Autism spectrum disorder: a neuro-immunometabolic hypothesis of the developmental origins

Fetal neuroinflammation and prenatal stress (PS) may contribute to lifelong neurological disabilities. Astrocytes and microglia play a pivotal role, but the mechanisms are poorly understood. Here, we test the hypothesis that via gene-environment interactions, fetal neuroinflammation and PS may reprogram glial immunometabolic phenotypes which impact neurodevelopment and neurobehavior. This glial-neuronal interplay increases the risk for clinical manifestation of autism spectrum disorder (ASD) in at-risk children. Drawing on genomic data from the recently published series of ovine and rodent glial transcriptome analyses with fetuses exposed to neuroinflammation or PS, we conducted a secondary analysis against the Simons Foundation Autism Research Initiative (SFARI) Gene database. We confirmed 21 gene hits. Using unsupervised statistical network analysis, we then identified six clusters of probable protein-protein interactions mapping onto the immunometabolic and stress response networks and epigenetic memory. These findings support our hypothesis. We discuss the implications for ASD etiology, early detection, and novel therapeutic approaches.Comment: Supplemental Table and Data: https://github.com/martinfrasch/ASD_origins_hypothesis. arXiv admin note: text overlap with arXiv:1812.06617 | This is a different study with related research context (relevance to ASD

Local to global policy as a catalyst for change: key messages

Feeding and nourishing a growing and changing global population in the face of rising numbers of chronically hungry people, slow progress on malnutrition, environmental degradation, systemic inequality, and the dire projections of climate change, demands a transformation in global food systems. Policy change at multiple levels is critical for catalysing an inclusive and sustainable transformation in food systems; global and regional policy are transformative only insofar as they are translated into ambitious national action with adequate support, including both public and private investment. Three areas of policy change show potential to be catalytic: 1) reducing emissions and increasing resilience, 2) tackling food loss and waste, and 3) shifting diets to promote nutrition and sustainability. Trade-offs mean a multi-sectoral approach to policymaking is needed, while inequalities in food systems necessitate transparent, inclusive processes and results. Gender inequality, in particular, must be addressed. Transformation demands participation and action from all actors

Unfolding the potential of the Virtual Water concept. What is still under debate?

The concept of virtual water refers to the volume of water used in the production of a commodity or a service. The concept was identified by the geographer Tony Allan in the early 1990s, to draw attention on the global economic processes that ameliorate local water deficits in the MENA region and elsewhere. Since its inception, the virtual water concept has inspired a flourishing literature on how to address global water resource scarcity vis-à-vis commodity production and consumption in a variety of disciplines, but also has been the object of a number of critiques. Against this backdrop, the aim of the study is, first, to conduct a thorough review of the conceptual definition of the concept, its critics and applications. Secondly, to analyse its theoretical underpinnings and, in particular, its relationship with economic theory. The study argues that, despite not being a policy tool itself, the virtual water concept can reveal aspects related to production, consumption and trade in goods which monetary indicators do not capture. Its potential as an indicator for informing decision-making in water management and policy, as well as commodity trade policy, still has to be fully unfolded

Effects of deposited sediments on temperate stream invertebrates

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Unfolding the potential of the Virtual Water concept. What is still under debate?

The concept of virtual water refers to the volume of water used in the production of a commodity or a service. The concept was identified by the geographer Tony Allan in the early 1990s, to draw attention on the global economic processes that ameliorate local water deficits in the MENA region and elsewhere. Since its inception, the virtual water concept has inspired a flourishing literature on how to address global water resource scarcity vis-à-vis commodity production and consumption in a variety of disciplines, but also has been the object of a number of critiques. Against this backdrop, the aim of the study is, first, to conduct a thorough review of the conceptual definition of the concept, its critics and applications. Secondly, to analyse its theoretical underpinnings and, in particular, its relationship with economic theory. The study argues that, despite not being a policy tool itself, the virtual water concept can reveal aspects related to production, consumption and trade in goods which monetary indicators do not capture. Its potential as an indicator for informing decision-making in water management and policy, as well as commodity trade policy, still has to be fully unfolded

Saturated areas through the lens: 2. Spatio-temporal variability of streamflow generation and its relationship with surface saturation

Investigating the spatio-temporal variability of streamflow generation is fundamental to interpret the hydrological and biochemical functioning of catchments. In humid temperate environments, streamflow generation is often linked to the occurrence of near stream surface saturated areas, which mediate hydrological connectivity between hillslopes and streams. In this second contribution of a series of two papers, we used salt dilution gauging to investigate the spatio-temporal variability of streamflow in different subcatchments and for different reaches in the Weierbach catchment (0.42 km2) and explored the topographical controls on streamflow variability. Moreover, we mapped stream network expansion and contraction dynamics. Finally, we combined the information on the spatio-temporal variability of streamflow with the characterization of riparian surface saturation dynamics of seven different areas within the catchment (mapped with thermal infrared imagery, as presented in our first manuscript). We found heterogeneities in the streamflow contribution from different portions of the catchment. Although the size of the contributing area could explain differences in subcatchments' and reaches' net discharge, no clear topographic controls could be found when considering the area-normalized discharge. This suggests that some local conditions exert control on the variability of specific discharge (e.g., local bedrock characteristics and occurrence of perennial springs). Stream network dynamics were found not to be very responsive to changes in catchment's discharge (i.e., total active stream length vs. stream outlet discharge relationship could be described through a power law function with exponent = 0.0195). On the contrary, surface saturation dynamics were found to be in agreement with the level of streamflow contribution from the correspondent reach in some of the investigated riparian areas. This study represents an example of how the combination of different techniques can be used to characterize the internal heterogeneity of the catchment and thus improve our understanding of how hydrological connectivity is established and streamflow is generated.</p