Search

The insurance effect of biodiversity—that diversity stabilises aggregate ecosystem properties—is mechanistically underlain by inter- and intraspecific trait variation in organismal responses to the environment. This variation, termedresponse diversity, is therefore a potentially critical determinant of ecological stability. However, response diversity has yet to be widely quantified, possibly due to difficulties in its measurement. Even when it has been measured, approaches have varied.Here, we review methods for measuring response diversity and from them distil a methodological framework for quantifying response diversity from experimental and/or observational data, which can be practically applied in lab and field settings across a range of taxa.Previous empirical studies on response diversity most commonly invoke response traits as proxies aimed at capturing species’ ecological responses to the environment. Our approach, which is based on environment-dependent ecological responses to any biotic or abiotic environmental variable, is conceptually simple and robust to any form of environmental response, including nonlinear responses. Given its derivation from empirical data on species’ ecological responses, this approach should more directly reflect response diversity than the trait-based approach dominant in the literature.By capturing even subtle inter- or intraspecific variation in environmental responses, and environment-dependencies in response diversity, we hope this framework will motivate tests of the diversity-stability relationship from a new perspective, and provide an approach for mapping, monitoring, and conserving this critical dimension of biodiversity.

Left ventricular (LV) dysfunction is an early, clinically detectable sign of cardiomyopathy in type 2 diabetes mellitus (T2DM) that precedes the development of symptomatic heart failure. Pre-clinical models of diabetic cardiomyopathy are essential to develop therapies that may prevent or delay the progression of heart failure. This study examined the molecular, structural, and functional cardiac phenotype of two rat models of T2DM induced by a high-fat diet (HFD) with a moderate- or high-sucrose content (containing 88.9 or 346 g/Kg sucrose, respectively), plus administration of low-dose streptozotocin (STZ). At eight weeks of age, male Sprague-Dawley rats commenced a moderate- or high-sucrose HFD. Two weeks later, rats received low-dose STZ (35 mg/kg i.p. for two days) and remained on their respective diets. LV function was assessed by echocardiography one week prior to endpoint. At 22 weeks of age, blood and tissues were collected post-mortem. Relative to chow-fed sham rats, diabetic rats on a moderate- or high-sucrose HFD displayed cardiac reactive oxygen species dysregulation, perivascular fibrosis, and impaired LV diastolic function. The diabetes-induced impact on LV adverse remodeling and diastolic dysfunction was more apparent when a high-sucrose HFD was superimposed on STZ. In conclusion, a high-sucrose HFD in combination with low-dose STZ produced a cardiac phenotype that more closely resembled T2DM-induced cardiomyopathy than STZ diabetic rats subjected to a moderate-sucrose HFD.

Despite substantial progress in understanding global biodiversity loss, major taxonomic and geographic knowledge gaps remain. Decision makers often rely on expert judgement to fill knowledge gaps, but are rarely able to engage with sufficiently large and diverse groups of specialists. To improve understanding of the perspectives of thousands of biodiversity experts worldwide, we conducted a survey and asked experts to focus on the taxa and freshwater, terrestrial, or marine ecosystem with which they are most familiar. We found several points of overwhelming consensus (for instance, multiple drivers of biodiversity loss interact synergistically) and important demographic and geographic differences in specialists’ perspectives and estimates. Experts from groups that are underrepresented in biodiversity science, including women and those from the Global South, recommended different priorities for conservation solutions, with less emphasis on acquiring new protected areas, and provided higher estimates of biodiversity loss and its impacts. This may in part be because they disproportionately study the most highly threatened taxa and habitats. Front Ecol Environ 2022;.

Theory and some evidence suggest that biodiversity promotes stability. However, evidence of how trophic interactions and environmental changes modulate this relationship in multitrophic communities is lacking. Given the current scenario of biodiversity loss and climate changes, where top predators are disproportionately more affected, filling these knowledge gaps is crucial. We simulated climate warming and top predator loss in natural microcosms to investigate their direct and indirect effects on temporal stability of microbial communities and the role of underlying stabilising mechanisms. Community stability was insensitive to warming, but indirectly decreased due to top predator loss via increased mesopredator abundance and consequent reduction of species asynchrony and species stability. The magnitude of destabilising effects differed among trophic levels, being disproportionally higher at lower trophic levels (e.g. producers). Our study unravels major patterns and causal mechanisms by which trophic downgrading destabilises large food webs, regardless of climate warming scenarios.

Historically, minimal significance has been given to the humoral immune response after liver transplantation and, despite antibodies against HLA antigens being present in 10-20% of patients awaiting transplant, the incidence of antibody mediated rejection (AMR) after ABO compatible (ABO-C) liver transplantation is low (1).Donor Specific Antibodies (DSA) can lead to early graft loss (2), but most patients awaiting liver transplant are not screened for HLA sensitisation and serum DSA measurement are only undertaken if AMR is suspected. We describe two cases of AMR occurring within one week of ABO-C liver transplantation with previously unreported biochemical and histological characteristics.

Mast cells and basophils have long been implicated in the pathogenesis of IgE-mediated hypersensitivity reactions. They express the high-affinity IgE receptor, FcϵRI, on their surface. Antigen-induced crosslinking of IgE antibodies bound to that receptor triggers a signaling cascade that results in activation, leading to the release of an array of preformed vasoactive mediators and rapidly synthesized lipids, as well as thede novoproduction of inflammatory cytokines. In addition to bearing activating receptors like FcεRI, these effector cells of allergy express inhibitory ones including FcγR2b, an IgG Fc receptor with a cytosolic inhibitory motif that activates protein tyrosine phosphatases that suppress IgE-mediated activation. We and others have shown that food allergen-specific IgG antibodies strongly induced during the course of oral immunotherapy (OIT), signalviaFcγR2b to suppress IgE-mediated mast cell and basophil activation triggered by food allergen challenge. However, the potential inhibitory effects of IgA antibodies, which are also produced in response to OIT and are present at high levels at mucosal sites, including the intestine where food allergens are encountered, have not been well studied. Here we uncover an inhibitory function for IgA. We observe that IgA binds mouse bone marrow-derived mast cells (BMMCs) and peritoneal mast cells. Binding to BMMCs is dependent on calcium and sialic acid. We also found that IgA antibodies inhibit IgE-mediated mast cell degranulation in an allergen-specific fashion. Antigen-specific IgA inhibits IgE-mediated mast cell activation early in the signaling cascade, suppressing the phosphorylation of Syk, the proximal protein kinase mediating FcεRI signaling, and suppresses mast cell production of cytokines. Furthermore, using basophils from a peanut allergic donor we found that IgA binds to basophils and that activation by exposure to peanuts is effectively suppressed by IgA. We conclude that IgA serves as a regulator of mast cell and basophil degranulation, suggesting a physiologic role for IgA in the maintenance of immune homeostasis at mucosal sites.

Vaccine-induced immune thrombosis and thrombocytopenia (VITT) syndrome is a new entity, characterised by severe thrombocytopenia and multiple sites of thrombosis1 . The presumed mechanism is driven by anti-platelet factor 4 (PF4) antibodies causing platelet activation1 . Donors with VITT syndrome have a particular relevance for liver transplantation (LT), due to the associated risk of passenger lymphocyte syndrome, and a predisposition for porto-mesenteric or hepatic vein thrombosis2 .

Diffusive transport of small ionic species through mucus layers is a ubiquitous phenomenon in physiology. However, some debate remains regarding how the various characteristics of mucus (charge of the polymers themselves, binding affinity of ions with mucus) impact the rate at which small ions may diffuse through a hydrated mucus gel. Indeed it is not even clear if small ionic species diffuse through mucus gel at an appreciably different rate than they do in aqueous solution. Here, we present a mathematical description of the transport of two ionic species (hydrogen and chloride) through a mucus layer based on the Nernst-Planck equations of electrodiffusion. The model explicitly accounts for the binding affinity of hydrogen to the mucus material, as well as the Donnan potential that occurs at the interface between regions with and without mucus. Steady state fluxes of ionic species are quantified, as are their dependencies on the chemical properties of the mucus gel and the composition of the bath solution. We outline a mechanism for generating enhanced diffusive flux of hydrogen across the gel region, and hypothesize how this mechanism may be relevant to the apparently contradictory experimental data in the literature.

The potential for forecasting the dynamics of ecological systems is currently unclear, with contrasting opinions regarding its feasibility due to ecological complexity. To investigate forecast skill within and across system complexity, we monitored a microbial system exposed to either constant or fluctuating temperatures in a five months long laboratory experiment. We tested how forecasting of species abundances depends on number and strength of interactions and on model size (number of predictors). We also tested how greater system complexity (i.e. the fluctuating temperatures) impacted these relations. We found that the more a species interacted, the weaker these interactions were and the better its abundance was predicted. Forecast skill increased with model size. Greater system complexity decreased forecast skill for three out of eight species. These insights into how abundance prediction depends on the embedding of the species within the system and on overall system complexity could improve species forecasting and monitoring.

The risk of fatal cardiovascular events is increased in patients with type 2 diabetes mellitus (T2DM). A major contributor to poor prognosis is impaired nitric oxide (NO•) signalling at the level of tissue responsiveness, termed NO• resistance. This study aimed to determine if T2DM promotes NO• resistance in the heart and vasculature and whether tissue responsiveness to nitroxyl (HNO) is affected.At 8 weeks of age, male Sprague-Dawley rats commenced a high-fat diet. After 2 weeks, the rats received low-dose streptozotocin (two intraperitoneal injections, 35 mg·kgInotropic, lusitropic and coronary vasodilator responses to DEA/NO were impaired in T2DM hearts, whereas responses to Angeli's salt were preserved or enhanced. Vasorelaxation to Angeli's salt was augmented in T2DM mesenteric arteries, which were hyporesponsive to the relaxant effects of SNP and DEA/NO.This is the first evidence that inotropic and lusitropic responses are preserved, and NO• resistance in the coronary and mesenteric vasculature is circumvented, by the HNO donor Angeli's salt in T2DM. These findings highlight the cardiovascular therapeutic potential of HNO donors, especially in emergencies such as acute ischaemia or heart failure.

The internal environment of cells is molecularly crowded, which requires spatial organization via subcellular compartmentalization. These compartments harbor specific conditions for molecules to perform their biological functions, such as coordination of the cell cycle, cell survival, and growth. This compartmentalization is also not static, with molecules trafficking between these subcellular neighborhoods to carry out their functions. For example, some biomolecules are multifunctional, requiring an environment with differing conditions or interacting partners, and others traffic to export such molecules. Aberrant localization of proteins or RNA species has been linked to many pathological conditions, such as neurological, cancer, and pulmonary diseases. Differential expression studies in transcriptomics and proteomics are relatively common, but the majority have overlooked the importance of subcellular information. In addition, subcellular transcriptomics and proteomics data do not always colocate because of the biochemical processes that occur during and after translation, highlighting the complementary nature of these fields. In this review, we discuss and directly compare the current methods in spatial proteomics and transcriptomics, which include sequencing- and imaging-based strategies, to give the reader an overview of the current tools available. We also discuss current limitations of these strategies as well as future developments in the field of spatial -omics.

Microbial communities in many ecosystems are facing a broad range of global change drivers, such as nutrient enrichment, chemical pollution, and temperature change. These drivers can cause changes in the abundance of taxa, the composition of communities, and the properties of ecosystems. While the influence of single drivers is already described in numerous studies, the effect and predictability of multiple drivers changing simultaneously is still poorly understood. In this study, we used 240 highly replicable oxic/anoxic aquatic lab microcosms and four drivers (fertilizer, glyphosate, metal pollution, antibiotics) in all possible combinations at three different temperatures (20 °C, 24 °C, and 28 °C) to shed light into consequences of multiple drivers on different levels of organization, ranging from species abundance to community and ecosystem parameters. We found (i) that at all levels of ecological organisation, combinations of drivers can change the biological consequence and direction of effect compared to single drivers (ii), that effects of combinations are further modified by temperature, (iii) that a larger number of drivers occurring simultaneously is often quite closely related to their effect size, and (iv) that there is little evidence that any of these effects are associated with the level of ecological organisation of the state variable. These findings suggest that, at least in this experimental ecosystem approximating a stratified aquatic ecosystem, there may be relatively little scope for predicting the effects of combinations of drivers from the effects of individual drivers, or by accounting for the level of ecological organisation in question, though there may be some scope for prediction based on the number of drivers that are occurring simultaneous. A priority, though also a considerable challenge, is to extend such research to consider continuous variation in the magnitude of multiple drivers acting together.

Three decades of research have demonstrated that biodiversity can promote the functioning of ecosystems. Yet, it is unclear whether the positive effects of biodiversity on ecosystem functioning will persist under various types of global environmental change drivers. We conducted a meta-analysis of 46 factorial experiments manipulating both species richness and the environment to test how global change drivers (i.e. warming, drought, nutrient addition or CO2 enrichment) modulated the effect of biodiversity on multiple ecosystem functions across three taxonomic groups (microbes, phytoplankton and plants). We found that biodiversity increased ecosystem functioning in both ambient and manipulated environments, but often not to the same degree. In particular, biodiversity effects on ecosystem functioning were larger in stressful environments induced by global change drivers, indicating that high-diversity communities were more resistant to environmental change. Using a subset of studies, we also found that the positive effects of biodiversity were mainly driven by interspecific complementarity and that these effects increased over time in both ambient and manipulated environments. Our findings support biodiversity conservation as a key strategy for sustainable ecosystem management in the face of global environmental change.

Histopathological assessment of liver tissue is essential for the management of patients with a whole range of liver tumours. Biopsies are often helpful in establishing the initial diagnosis of a lesion. Intraoperative frozen sections can provide the surgeon with valuable information regarding the nature of a liver lesion and/or the clearance of surgical margins. Examination of tissue from resection and transplant operations is important in confirming the preoperative diagnosis and for providing additional prognostic information. This article outlines the pathway for the processing of liver tumour tissue in the histopathology laboratory, before discussing the pathological features of the more commonly encountered benign and malignant liver tumours. Included within this discussion are epithelial tumours of both hepatocellular and biliary derivation, mesenchymal lesions and metastatic liver lesions. The age of the patient and the presence or absence of background liver disease are major determinants of the likely differential diagnosis of a liver lesion. The article also summarizes the key data items included in a histopathology report for surgical excision specimens.

Several studies have shown that failure to resolve inflammation may contribute to the progression of many chronic inflammatory disorders. It has been suggested targeting the resolution of inflammat...

Aim: Impairment of tissue responsiveness to exogenous and endogenous nitric oxide (NO•), known as NO• resistance, occurs in many cardiovascular disease states, prominently in diabetes and especiall...

Non-consumptive effects (NCEs) of predators on prey, such as induced defensive strategies, are frequently neglected in the analysis of predator-prey interactions. Yet these effects can have demographic impacts as strong as consumption. As a counterpart to NCEs, resource-availability effects (RAEs) can prompt changes in predators as well, e.g., in their foraging behavior. We studied NCEs and RAEs in the ciliate predator-prey pairDidinium nasutumandParamecium caudatum. We examined the dependence of prey/predator swimming speed and body size on predator/prey presence. We also investigated prey spatial grouping behavior and the dependence of predator movement on local prey abundance. We collected individual movement and morphology data through videography of laboratory-based populations. We compared swimming speeds and body sizes based on their distributions. We used linear models to respectively quantify the effects of local prey abundance on predator displacements and of predator presence on prey grouping behavior. In the presence of prey, predator individuals swam more slowly, were bigger and made smaller displacements. Further, their displacements decreased with increasing local prey abundance. In contrast, in the presence of predators, proportionally more prey individuals showed a fast-swimming behavior and there was weak evidence for increased prey grouping. Trait changes entail energy expenditure shifts, which likely affect interspecific interactions and populations, as has been shown for NCEs. Less is known about the link between RAEs and demography, but it seems likely that the observed effects scale up to influence community and ecosystem stability, yet this remains largely unexplored.Significance StatementTo maximize their fitness, organisms balance investment in foraging and avoiding being eaten. The behaviors of prey and predators are thus expected to depend on the presence and absence of each other and serve either to boost the chances of predation evasion or to increase predation success. Here we provide an example of the co-dependence of behaviors in the predator-prey pairDidinium nasutumandParamecium caudatum. We show that the predator slows down and searches in smaller areas when prey are present, while the prey speeds up and possibly groups more as a response to the presence of predators. Such behavioral changes are likely to have a demographic and community impact that is not accounted for with common measures of predators-prey interactions.

The control of transport through mucus layers is a ubiquitous phenomenon in physiological systems. Mucus is often tasked with the mediation of passive, diffusive transport of small ionic species. However, questions remain regarding how mucin gel characteristics (charge density of the polymeric network, binding affinity of ions with mucus) govern the rate at which ions diffuse through mucus layers. Experimental studies measuring hydrogen diffusion through gastric mucus have provided conflicting results, and it is not clear if the rate of ionic diffusion through mucus layers is appreciably different than in aqueous environments (depending on experimental preparation). Here, we present a mathematical analysis of electrodiffussion of two ionic species (hydrogen and chloride) through a mucus layer. In addition to accounting for the chemical binding of hydrogen to the mucus network, we enforce a zero net current condition (as mucus layers in physiological systems are not generally electrogenic) and calculate the Donnan potential that occurs at the edge of the mucus layer. The model predicts the steady-state fluxes of ionic species and the induced potential across the layer. We characterize the dependence of these quantities on the chemical properties of the mucus gel, the composition of the bath solution, and the molecular mobility of the dissolved anion, and we show that the model predictions are consistent with a large portion of the experimental literature. Our analysis predicts that mucus layers generically slow the diffusive transport of hydrogen, but that chemical binding with the network attenuates this effect.

Introduction: The risk of fatal cardiovascular events is increased in patients with type 2 diabetes mellitus (T2DM). A major contributor to poor prognosis is impaired nitric oxide (NO•) signalling at the level of tissue responsiveness, termed NO• resistance. Nitroxyl (HNO) induces positive inotropic and lusitropic effects in healthy and failing hearts. Hypothesis: We hypothesised that in a rodent model, T2DM will promote, and HNO will circumvent, NO• resistance in the myocardium and coronary vasculature. Methods: At 8 weeks of age, male Sprague-Dawley rats commenced a high-fat diet. After two weeks, the rats received low-dose streptozotocin (two intraperitoneal injections, 35 mg/kg, over two consecutive days), and continued the diet. Twelve weeks later, hearts were Langendorff-perfused to assess responses to the NO• donor diethylamine NONOate (DEA/NO) and the HNO donor Angeli’s salt. Results: Inotropic, lusitropic and coronary vasodilator responses to DEA/NO were impaired, and responses to Angeli’s salt were preserved or enhanced, in T2DM hearts compared with non-diabetic hearts. Conclusions: This is the first evidence that inotropic and lusitropic responses are preserved, and NO• resistance in the coronary vasculature is circumvented, by the HNO donor Angeli’s salt in T2DM. These findings highlight the cardiovascular therapeutic potential of HNO donors, especially in cardiac emergencies such as acute ischaemia or heart failure. Figure 1. Dose-response curves and maximal responses to DEA/NO or Angeli's salt in diabetic or non-diabetic hearts. (A-C) LV+dP/dt, (D-F) LV-dP/dt and (G-I) coronary flow rate. Data expressed as change from baseline (denoted by Δ), mean ± SEM. Data analysed by two-way RM ANOVA with Sidak's post-hoc test. *P

Introduction: We have previously demonstrated that the naturally-occurring anti-inflammatory and pro-resolving protein Annexin-A1 (Anx-A1) limits the acute inflammatory response post myocardial infarction, but its impact on chronic inflammation, such as hypertension, has not been explored. This study aims to investigate the role of Anx-A1 in a preclinical model of hypertension, induced by angiotensin-II (Ang-II). Methods: 15-week-old male C57BL/6 or ANXA1 -/- were anesthetized (isoflurane, 2-4% v/v) and implanted with an osmotic minipump randomly assigned to receive Ang-II (0.7mg/kg/day) or vehicle (saline). Radiotelemetry recordings of blood pressure were taken at 10 intermittent timepoints from baseline to the end of the 29-day infusion period. Animals were euthanized with pentobarbitone (100mg/kg; i.p.) at endpoint and organ weights recorded and normalized to bodyweight. Left ventricle (LV) samples were stained with picrosirius red to assess total LV collagen deposition. Results: Ang II-induced mice at the end of the study had elevated mean arterial pressure (MAP), cardiac hypertrophy and fibrosis compared to normotensive mice (Table). Anx-A1 deficient mice given Ang II had an even greater increase in MAP and cardiac remodeling compared to WT. Interestingly, MAP of Anx-A1 deficient mice at baseline is significantly higher compare to C57BL/6 counterparts (Table). Conclusion: This is the first study to demonstrate that deficiency of Anx-A1 exaggerates cardiac remodeling in AngII-induced hypertension, suggesting that endogenous Anx-A1 might play previously unappreciated physiological role in regulating blood pressure. This supports the development of Anx-A1 based pharmacotherapy against hypertension-induced cardiac damage.

It is generally accepted that the gastric mucosa and adjacent mucus layer are critical in the maintenance of a pH gradient from stomach lumen to stomach wall, protecting the mucosa from the acidic environment of the lumen and preventing auto-digestion of the epithelial layer. No conclusive study has shown precisely which physical, chemical, and regulatory mechanisms are responsible for maintaining this gradient. However, experimental work and modeling efforts have suggested that concentration dependent ion-exchange at the epithelial wall, together with hydrogen ion/mucus network binding, may produce the enormous pH gradients seen in vivo. As of yet, there has been no exhaustive study of how sensitive these modeling results are with respect to variation in model parameters, nor how sensitive such a regulatory mechanism may be to variation in physical/biological parameters. In this work, we perform sensitivity analysis (using Sobol' Indices) on a previously reported model of gastric pH gradient maintenance. We quantify the sensitivity of mucosal wall pH (as a proxy for epithelial health) to variations in biologically relevant parameters and illustrate how variations in these parameters affects the distribution of the measured pH values. In all parameter regimes, we see that the rate of cation/hydrogen exchange at the epithelial wall is the dominant parameter/effect with regards to variation in mucosal pH. By careful sensitivity analysis, we also investigate two different regimes representing high and low hydrogen secretion with different physiological interpretations. By complementing mechanistic modeling and biological hypotheses testing with parametric sensitivity analysis we are able to conclude which biological processes must be tightly regulated in order to robustly maintain the pH values necessary for healthy function of the stomach.

Lower extremity artery disease (LEAD) is a chronic inflammatory disease that occurs when atherosclerotic plaques form in the lower extremities, which may lead to amputation if not manged properly. Given clinical standardcare (pharmacological and surgical) have limited efficacy in LEAD, developing novel strategies to manage LEAD remains an unmet clinical need. Given that active resolution of inflammation is essential to facilitate tissue healing and repair, failure to resolve inflammation may lead to chronic inflammation, dysregulated cellular homeostasis and adverse tissue remodeling. Several studies have demonstrated the importance of the balance between endogenous pro-resolving mediators and pro-inflammatory factors. There is growing evidence to suggest endogenous pro-resolving mediators engage with pro-resolving G-protein-coupled receptors to reduce the initiation and progression of inflammatory responses and to increase therapeutic angiogenesis in LEAD. Here, we highlight the mechanisms and the consequences of resolved inflammation, and the therapeutic potential of endogenous pro-resolving mediators-based strategy for this devastating disease.

Warming increases the metabolic demand of consumers1, strengthening their feeding interactions2. This could alter energy fluxes3–5 and even amplify extinction rates within the food web6–8. Such effects could simplify the structure and dynamics of ecological networks9,10, although an empirical test in natural systems has been lacking. Here, we tested this hypothesis by characterizing around 50,000 directly observed feeding interactions across 14 naturally heated stream ecosystems11–15. We found that higher temperature simplified food-web structure and shortened the pathways of energy flux between consumers and resources. A simple allometric diet breadth model10,16 predicted 68–82% of feeding interactions and the effects of warming on key food-web properties. We used model simulations to identify the underlying mechanism as a change in the relative diversity and abundance of consumers and their resources. This model shows how warming can reduce the stability of aquatic ecosystems by eroding the structural integrity of the food web. Given these fundamental drivers, such responses are expected to be manifested more broadly and could be predicted using our modelling framework and knowledge of how warming alters some routinely measured characteristics of organisms. Observations of feeding interactions show that warming simplifies the structure of food webs in stream ecosystems. Simulations show that consumer diversity and changes in abundance drive this simplification and can reduce ecosystem stability.

Warming and nutrient enrichment are major environmental factors shaping ecological dynamics. However, cross-scale investigation of their combined effects by linking theory and experiments is lacking. We collected data from aquatic microbial ecosystems investigating the interactive effects of warming (constant and rising temperatures) and enrichment across levels of organisation and contrasted them with community models based on metabolic theory. We found high agreement between our observations and theoretical predictions: we observed in many cases the predicted antagonistic effects of high temperature and high enrichment across levels of organisation. Temporal stability of total biomass decreased with warming but did not differ across enrichment levels. Constant and rising temperature treatments with identical mean temperature did not show qualitative differences. Overall, we conclude that model and empirical results are in broad agreement due to robustness of the effects of temperature and enrichment, that the mitigating effects of temperature on effects of enrichment may be common, and that models based on metabolic theory provide qualitatively robust predictions of the combined ecological effects of enrichment and temperature.

Effective response to groundwater salinity in the developing world may critically safeguard drinking-water supplies. Groundwater resources throughout rural Africa are exploited by a vast and increasing number of hand-pumped boreholes for community supply. Our research in TA Ngabu (Shire Valley), Southern Malawi aims to: define groundwater-salinity problem occurrence within the semi-arid alluvial-valley aquifer, rural developing-world setting; critique current capacity to respond; and, to discuss future response options - in particular considering the need to explore alternative options that boldly go beyond the world of hand-pumped groundwater supply. Salinity problem definition was achieved through survey of 419 hand-pumped boreholes that revealed widespread brackish groundwater leading to non-potable (unpalatable) drinking-water supplies. Persistent non-functionality or abandonment of boreholes was typically ascribed to salinity. Whilst salinity is conceptualised to arise from shallow-groundwater evaporation, formation-evaporite dissolution and faulted-area upwelling, sparse data locally renders attribution of salinity sources to individual boreholes difficult. There is a significant need to better resolve the vertical distribution of salinity and local controlling processes. Problem response capacity was hampered by multiple factors, including, sector inertia, low drilling costs compromising water-point integrity, and lack of technical vision for alternatives. Various recommendations are made to improve response capacity continuing to work at the hand-pump supply scale. However, in areas where salinity is significant, exploring the feasibility of other options is advocated in conjunction with technical capacity development. Groundwater options may utilise high borehole yields possible from alluvial aquifers, grossly under-exploited by hand pumps. Groundwater at depth, albeit of unknown quality typically, or pipeline transfers of probable good-quality groundwater from valley-margin units, should be considered. Surface-water pipeline supplies may be viable for (growing) population centres. Canal-fed irrigation schemes (pending for the area), should be multiple-use, protective of groundwater and embrace pipeline drinking-water supply and managed-aquifer-recharge opportunities. Advancing desalination technologies, although presently unaffordable, should be kept under review.

In acute myocardial infarction (AMI), the first line of treatment is to rapidly restore blood flow to the ischemic myocardium to limit infarct size. It is now well established that though clearly beneficial, the positive outcomes of this intervention are limited by injury in response to the reperfusion itself in addition to the prior ischemia. This process is described as reperfusion injury and is considered to contribute to the arrhythmias, microvascular dysfunction and impaired cardiac contractility that is observed even after the restoration of coronary blood flow. Thus an important, currently unmet, therapeutic challenge is to address the outcomes of this reperfusion injury. In this article, we review the evidence that flavonols and flavones may prove useful in preserving cardiac function after ischemia and reperfusion and consider the possible mechanisms, in particular, the inhibition of kinases, by which they may exert protection.

The interspecific interactions within and between adjacent ecosystems strongly depend on the changes in their abiotic and biotic components. However, little is known about how climate change and biodiversity loss in a specific ecosystem can impact the multiple trophic interactions of different biological groups within and across ecosystems. We used natural microecosystems (tank-bromeliads) as a model system to investigate the main and interactive effects of aquatic warming and aquatic top predator loss (i.e. trophic downgrading) on trophic relationships in three integrated food web compartments: (a) aquatic micro-organisms, (b) aquatic macro-organisms and (c) terrestrial predators (i.e. via cross-ecosystem effects). The aquatic top predator loss substantially impacted the three food web compartments. In the aquatic macrofauna compartment, trophic downgrading increased the filter feeder richness and abundance directly and indirectly via an increase in detritivore richness, likely through a facilitative interaction. For the microbiota compartment, aquatic top predator loss had a negative effect on algae richness, probably via decreasing the input of nutrients from predator biological activities. Furthermore, the more active terrestrial predators responded more to aquatic top predator loss, via an increase in some components of aquatic macrofauna, than more stationary terrestrial predators. The aquatic trophic downgrading indirectly altered the richness and abundance of cursorial terrestrial predators, but these effects had different direction according to the aquatic functional group, filter feeder or other detritivores. The web-building predators were indirectly affected by aquatic trophic downgrading due to increased filter feeder richness. Aquatic warming did not affect the aquatic micro- or macro-organisms but did positively affect the abundance of web-building terrestrial predators. These results allow us to raise a predictive framework of how different anthropogenic changes predicted for the next decades, such as aquatic warming and top predator loss, could differentially affect multiple biological groups through interactions within and across ecosystems.As interações interespecíficas dentro e entre ecossistemas adjacentes dependem fortemente das mudanças de seus componentes abióticos e bióticos. Entretanto, pouco se sabe sobre como mudanças climáticas e a perda de biodiversidade em um ecossistema específico pode impactar as múltiplas interações tróficas de diferentes grupos biológicos dentro e entre ecossistemas. Nós utilizamos micro ecossistemas naturais (bromélias-tanque) como sistema modelo para investigar os efeitos individuais e interativos do aquecimento e da perda de predadores aquáticos (simplificação trófica) nas relações tróficas em três compartimentos integrados da teia alimentar: i) micro-organismos aquáticos, ii) macroorganismos aquáticos e iii) predadores terrestres (via efeito entre ecossistemas). A perda de predadores de topo aquáticos afetou substancialmente os três compartimentos da rede trófica. No compartimento da macrofauna aquática, a simplificação trófica aumentou a riqueza e abundância de filtradores, direta e indiretamente, por meio de um aumento da riqueza de espécies de detritívoros, provavelmente através de uma interação de facilitação. Para o compartimento da microbiota, a perda de predadores de topo aquáticos teve um efeito negativo sobre a riqueza de espécies de algas, provavelmente por meio da diminuição da entrada de nutrientes provenientes das atividades biológicas dos predadores. Além disso, os predadores terrestres mais ativos responderam mais à perda de predadores de topo aquáticos, por meio de um aumento de alguns componentes da macrofauna aquática, do que predadores terrestres mais estacionários. A simplificação trófica aquática alterou indiretamente a riqueza e abundância de predadores cursoriais terrestres, mas esses efeitos tiveram direção diferente de acordo com o grupo funcional aquático, filtradores ou outros detritívoros. Os predadores construtores de teias foram indiretamente afetados pela simplificação trófica aquática devido ao aumento da riqueza de filtradores. O aquecimento aquático não afetou os micro ou macro organismos aquáticos, mas afetou positivamente a abundância de predadores terrestres construtores de teias. Esses resultados nos permitem levantar um quadro preditivo de como diferentes mudanças antropogênicas preditas para as próximas décadas, como o aquecimento e a perda de predadores de topo aquáticos, podem afetar diferencialmente vários grupos biológicos por meio de interações dentro e entre os ecossistemas.

This and the next chapter involve us working through the process of getting insights from data. We have chosen a research subject that should have some interest to us all: food. More specifically, what bats eat. In this chapter you will experience a clearly specified set of research questions, learn how the study was performed and why it was done that way, and learn how to prepare your computer, R, and RStudio for the project, and how to read the dataset into R. The chapter also covers how you can clean, tidy, and manipulate the data in R. These are the solid foundations from which robust and reliable insights can grow.

In this chapter we go through some miscellaneous R topics, all of which you experienced briefly in the bat diet workflow demonstration. These include pipes, a mechanism for moving data from one operation to another; strings, how words and text are represented in computers using ‘stringr’; dates and times, until recently a proper pain anywhere on a computer, but now much simpler and straightforward to deal with, using the lubridate package; and pivoting, changing data from long to wide format, and wide to long, using the ‘pivot_longer’ and ‘pivot_wider’ functions in the tidyr package.

In the previous two chapters we experienced/demonstrated a data analysis workflow about variation in the diets of bats. In this and the next few chapters we will take a deeper dive into the details of R and of concepts. In this chapter, you will become much better acquainted with the wonderful world of the dplyr package. We look more carefully at the some of the core dplyr functions: ‘select’ (get some columns), ‘mutate’ (make a new column), ‘filter’ (get some rows), ‘arrange’ (order the rows), ‘group_by’ (add grouping information), and ‘summarise’ (calculate summary information about groups).

After reading this book, what comes next? There is a lot that we decided to leave out of the book that we would have loved to put in. This chapter includes some pointers about what we left out, and what you could now start exploring. We also include a section on reproducibility, which covers the basics of what reproducibility is, why we might care about making our work reproducible, and what practical moves we can make towards achieving this.