Mangrove forests as a nature-based solution for coastal flood protection: Biophysical and ecological considerations

Nature-based coastal protection is increasingly recognised as a potentially sustainable and cost-effective solution to reduce coastal flood risk. It uses coastal ecosystems such as mangrove forests to create resilient designs for coastal flood protection. However, to use mangroves effectively as a nature-based measure for flood risk reduction, we must understand the biophysical processes that govern risk reduction capacity through mangrove ecosystem size and structure. In this perspective, we evaluate the current state of knowledge on local physical drivers and ecological processes that determine mangrove functioning as part of a nature-based flood defence. We show that the forest properties that comprise coastal flood protection are well-known, but models cannot yet pinpoint how spatial heterogeneity of the forest structure affects the capacity for wave or surge attenuation. Overall, there is relatively good understanding of the ecological processes that drive forest structure and size, but there is a lack of knowledge on how daily bed-level dynamics link to long-term biogeomorphic forest dynamics, and on the role of combined stressors influencing forest retreat. Integrating simulation models of forest structure under changing physical (e.g. due to sea-level change) and ecological drivers with hydrodynamic attenuation models will allow for better projections of long-term natural coastal protection.     

In vitro and in vivo metabolism of the progestagen Org 30659 in several species

The metabolism of Org 30659 [(17alpha)-17-hydroxy-11-methylene-19-norpregna-4, 15-dien-20-yn-3-one], a new potent progestagen currently under clinical development by NV Organon for use in oral contraceptive and hormone replacement therapy, was studied in vivo after oral administration to rats and monkeys and in vitro using rat, rabbit, monkey, and human liver microsomes and rat and human hepatocytes. After oral administration of [7-3H]Org 30659 to rats and monkeys, Org 30659 was extensively metabolized in both species. Fecal excretion appeared to be the main route of elimination. In rats, opening of the A-ring, resulting in a 2-OH,4-carboxylic acid, 5alpha-H metabolite of Org 30659, was the major metabolic route in vivo. Other metabolic routes involved the introduction of an OH group at C15beta, followed by a shift of the Delta15-double bond to a 16/17-double bond with subsequent removal of the OH group at C17 and reduction of the 3-keto,Delta4 moiety followed by sulfate conjugation of the 3-OH substituent. These metabolic routes observed in vivo were also major routes in incubations with rat hepatocytes. In rat liver microsomes, Org 30659 was metabolized by reduction of the 3-keto,Delta4 moiety. Rat hepatocyte incubations with Org 30659 were more representative of the in vivo metabolism of Org 30659, compared with rat microsomal incubations. Both in vitro and in vivo, the majority of the metabolites were 3alpha-OH,4,5alpha-dihydro derivatives. In monkeys, Org 30659 was mainly metabolized at the C3- and C17-positions in vivo. The 3-keto moiety was reduced to both 3beta-OH and 3alpha-OH substituents. In addition to phase I metabolites, glucuronic acid conjugates were observed in vivo. In monkey liver microsomes, the 6beta-OH metabolite of Org 30659 was the major metabolite present. Similar to the monkey liver microsomes, rabbit and human liver microsomes converted Org 30659 to the 6beta-OH metabolite. This metabolite was also the major metabolite in incubations with human hepatocytes.     

Supporting reflective web searching in elementary schools

In this contribution, two design experiments are presented in which reflective web searching is implemented in six elementary classrooms. Reflective web searching is viewed to comprise three steps: (1) develop ownership over search questions, (2) interpret and personalize web content, and (3) adapt web content into personally meaningful answers. A portal and a worksheet supported reflective web searching. A wide range of qualitative data, including observations, interviews and group products, was collected to gain insight in the emerging practices. The findings show that the portal and worksheet successfully contributed to the development of ownership, and the interpretation and personalization of retrieved information. Enabling children to search the web collaboratively further enhanced interpretation and personalization. The prototypes of both portal and worksheet were improved across the design experiments, and their success rates increased. Despite the improvements, the process of adaptation was not sufficiently supported by the portal and worksheet.     

No warning for slow transitions

A rise in fragility as a system approaches a tipping point may be sometimes estimated using dynamical indicators of resilience (DIORs) that measure the characteristic slowing down of recovery rates before a tipping point. A change in DIORs could be interpreted as an early warning signal for an upcoming critical transition. However, in order to be able to estimate the DIORs, observational records need to be long enough to capture the response rate of the system. As we show here, the required length of the time series depends on the response rates of the system. For instance, the current rate of anthropogenic climate forcing is fast relative to the response rate of some parts of the climate system. Therefore, we may expect difficulties estimating the resilience from modern time series. So far, there have been no systematic studies of the effects of the response rates of the dynamical systems and the rates of forcing on the detectability trends in the DIORs prior to critical transitions. Here, we quantify the performance of the resilience indicators variance and temporal autocorrelation, in systems with different response rates and for different rates of forcing. Our results show that the rapid rise of anthropogenic forcing to the Earth may make it difficult to detect changes in the resilience of ecosystems and climate elements from time series. These findings suggest that in order to determine with models whether the use of the DIORs is appropriate, we need to use realistic models that incorporate the key processes with the appropriate time constants.     

The potential of flavonoids in the treatment of non-alcoholic fatty liver disease

The contemporary pathophysiological model of non-alcoholic fatty liver disease (NAFLD) comprises multiple parallel pathways with a dynamic cross talk that cumulate in steatosis and inflammation, and ultimately fibrosis, cirrhosis, liver failure, and hepatocellular carcinoma. So far, no pharmacological treatment has been approved. A major impediment of drugs, in general, is that they are intended to act on one single target in the pathology of a disease. However, the multitude of pathways involved in the pathogenesis of NAFLD underpins the need for treatments that address these various pathways. Interestingly, flavonoids have been found to have positive effects on lipid metabolism, insulin resistance, inflammation, and oxidative stress, the most important pathophysiological pathways in NAFLD. This puts flavonoids in the spotlight for the treatment of NAFLD and prompted us to review the existing evidence for the use of these food-derived compounds in the treatment of NAFLD.     

Capillary electrophoresis with lamp-based wavelength-resolved fluorescence detection for the probing of protein conformational changes

Native protein fluorescence spectra encompass information on protein conformation. In this study, capillary electrophoresis (CE) combined with lamp-based wavelength-resolved fluorescence detection (wrFlu) is presented as a novel tool for the analysis of protein mixtures and the monitoring of protein unfolding. The CE-wrFlu system provides three-dimensional data (time, emission wavelength, intensity) from which electropherograms and accurate emission spectra of separated proteins can be extracted. For model proteins, linear detector responses (peak height vs concentration) were obtained (R(2) > 0.96) with detection limits (LODs) in the 6-32 nM range. The minimum protein concentration required for precise determination of the maximum emission wavelength by CE-wrFlu was about 15 times the LOD. Unfolding of various model proteins was induced by protein incubation and analysis in background electrolyte (BGE) containing 7.0 M urea. CE-wrFlu of the unfolded species revealed peaks with clear red-shifted spectra, which adequately corresponded to reference spectra obtained on a standard spectrophotometer. Moreover, unfolded proteins showed a significant decrease in effective electrophoretic mobility (after correction for BGE viscosity) due to the increase of their molecular hydrodynamic radii. It is concluded that the CE-wrFlu system provides two independent indicators for changes in protein folding and will allow the simultaneous assessment of protein purity and conformation.     

Combined high-pressure and thermal treatments for processing of tomato puree: evaluation of microbial inactivation and quality parameters

The effects of combined high-pressure thermal treatments on consistency, viscosity, colour, lycopene content, enzyme activity and micro-organisms were determined, and compared to conventional pasteurisation and sterilisation processes of tomato puree. High-pressure processing at ambient temperature (HPP) improved the colour and viscosity compared to heat pasteurisation, while the water binding capacity and lycopene content were unaffected by HPP. Products treated at 700 MPa, 20 °C resulted in inactivation of the natural flora to a level below the detection limit. After pressure treatment and during chilled storage a increase in viscosity was observed. HPP caused partial inactivation of polygalacturonase (70%), but activation of pectin methylesterase. After high-pressure sterilisation treatments combined with elevated starting temperatures (≥80 °C, HPS, one or two pulses) an ambient stable product was obtained. HPS (one pulse, 700 MPa, 30 s, 90 °C) reduced B. stearothermophilus spore contamination level in inoculated meatballs in tomato puree with at least 4.5 log units. HPS resulted in more than 99% inactivation of polygalacturonase and pectin methylesterase. HPS resulted in a lower viscosity compared to conventional sterilised samples, whereas the water binding capacity was improved. Colour appreciation was improved and lycopene content was retained compared to a 40% loss after conventional sterilisation.     

Drought Governance in Transition: a Case Study of the Meuse River Basin in the Netherlands

Water Resources Management - The Netherlands is internationally renowned for its flood risk management, but three consecutive dry years between 2018–2020 fuelled the debate on how to deal...     

Increased circulating cytokine receptors and ex vivo interleukin-1 receptor antagonist and interleukin-1beta production but decreased tumour necrosis factor-alpha production after a 5-km run

BACKGROUND: The purpose of this study was to examine the effect of a 5-km run on blood leucocytes, acute-phase proteins and cytokines. In addition, cytokines were measured in the supernatants from whole-blood cell cultures incubated with lipolysaccharide (LPS). METHODS: Ten healthy, recreational trained, athletes (three women, seven men) volunteered for this investigation. Samples were drawn just before, immediately after and at 3 h, at 24 h and at 48 h after the race. RESULTS: Exercise induced a transient leucocytosis (P = 0. 0002) and a mild acute-phase reaction with increase in plasma C-reactive protein (CRP) (P = 0.0115) but not in serum amyloid A (SAA) concentrations. Although plasma interleukin 6 (IL-6) was undetectable and soluble interleukin-1 receptor type II (IL-1sRII) remained unchanged, interleukin-1 receptor antagonist (IL-1ra) concentrations were elevated directly after the race with a further increase at 3 h (P < 0.0001). Soluble tumour necrosis factor (TNF) receptors were increased immediately after the run, but the effect was more marked for sTNFr p55 (two-fold increase; P < 0.0001) than for sTNFr p75 (1.16-fold increase; P = 00007). In cell cultures, the LPS-induced release of the inflammatory cytokines doubled for IL-1beta (P < 0.0001) and for IL-1ra (P < 0.0001). In contrast, TNF-alpha production decreased after the run, and a nadir was reached at 24 h (P < 0.0001). CONCLUSION: These results suggest that a 5-km run elicits both the production of acute-phase mediators (leucocytosis and elevation of CRP) and anti-inflammatory counter-regulation as judged by the increase in circulating concentrations of IL-1ra, sTNFr p55, and sTNFrp75 and down-regulation of LPS-stimulated TNF-alpha production.