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High mountain areas are especially vulnerable to global warming, as they experience faster temperature changes than lowlands in a climate change context. Notably, increased temperatures and frequency of extreme flooding and droughts, and the consequent decrease in ice cover and water availability fluctuations, will induce important physical changes in alpine freshwater systems. Thus, assessing thermal limits and exploring overwintering strategies of aquatic alpine insects is pivotal to understanding how aquatic communities of high‐mountain fresh waters will respond to climate change. However, knowledge on these topics is still scarce for aquatic alpine insects.Here, the thermal biology of adults of five diving beetle species from alpine lakes located in the Sierra Nevada mountain range (southern Iberia) was studied. Cold tolerance was measured estimating the supercooling point (SCP), lower lethal temperature (LLT), tolerance to ice enclosure and to submersion, whereas heat tolerance was assessed from the heat coma temperature and upper lethal temperature.All of the species survived ice enclosure for 3 h. Furthermore, three of the studied species had SCPs higher than their LLTs, suggesting that they could be freeze‐tolerant. All species except Agabus nevadensis also were tolerant to submersion, which could be a key adaptation for overwintering underwater below the ice cover as adults, reducing risk from freezing conditions in the air. The species did not differ significantly in their upper thermal limits, which were similar to those of other dytiscids from lower altitudes.Overall, our results suggest that increasing temperatures is not expected to be the most important threat for the water beetle populations in Sierra Nevada, but rather the colonisation of alpine lakes by lowland dytiscids in a warmer climate scenario. [ABSTRACT FROM AUTHOR]

Physiological traits are key in determining the vulnerability of narrow range, highly specialized animals to climate change. It is generally predicted that species from more stable environments possess lower thermal tolerance breadths and thermal plasticity than those from more variable habitats – the so‐called 'climatic variability hypothesis'. However, evolutionary trade‐offs between thermal breadth and its plasticity are also seen in some taxa, and the evolution of thermal physiology remains poorly understood. Subterranean environments are excellent systems for exploring these issues, being characterized by stable climatic conditions, with environmental variability increasing predictably from deep to shallow habitats. Acclimation capacity will be fundamental in determining the sensitivity of subterranean species to climate change, since they have poor dispersal capacity and limited possibility to exploit thermally different microhabitats in the uniform cave environment. We assessed critical thermal maximum (CTmax) and short‐term heat acclimation capacity in three related beetles (Leiodidae: Leptodirini) with differing degrees of specialization to the subterranean environment (deep, shallow and facultatively subterranean, respectively) and therefore exposed to contrasting thermal variability in nature. Only the facultative subterranean species showed any acclimatory capacity, also having the highest CTmax across the taxa studied. However, this species might experience the highest thermal stress in its habitat under climate change. The studied subterranean specialists will be poorly able to cope physiologically with temperature increase, but in contrast exposed to lower magnitude and rate of warming. Our results fit the climatic variability hypothesis, suggesting that adaptation to cave conditions has selected against the retention of acclimation mechanisms. We show that the pathways that determine vulnerability of subterranean species to climate change depend on their degree of specialization to deep subterranean environments. This information, combined with evaluation of exposure to climatic changes at their present locations, is fundamental in identifying species or populations at greatest risk. [ABSTRACT FROM AUTHOR]

Following the entry into force of the IPPC directive, the activities that it affects, which include the ceramic sector, have needed to control fugitive particle emissions by implementing corrective measures that often entail significant economic costs. In the most demanding cases, the Integrated Environmental Authorisations (IEA) awarded to companies in the ceramic industry require total enclosure of the raw materials handling operations. This paper evaluates the technical, economic, and environmental feasibility of the implementation of a total enclosure or containment system as a way of reducing fugitive particle emissions, as this is considered one of the Best Available Techniques (BAT). The study was carried out on the raw materials reception, handling, and storage operations at a ceramic company that manufactures spray-dried powder granules.Tras la entrada en vigor de la Directiva de Prevención y Control Integrados de la Contaminación (Directiva IPPC) las actividades afectadas por la misma, incluidas las del sector cerámico, se han visto obligadas a controlar la emisión de partículas difusas mediante la implantación de medidas correctoras, que en muchos casos suponen un impacto económico significativo. En los casos más exigentes, las Autorizaciones Ambientales Integradas (AAIs) otorgadas a empresas del sector cerámico requieren el cerramiento total de las operaciones de gestión de materias primas. En el presente trabajo se evalúa la viabilidad técnica, económica y ambiental de la implantación de un sistema de cerramiento o confinamiento total como medida de reducción de emisiones difusas al considerarse una de las Mejores Técnicas Disponibles (MTDs). El estudio se ha realizado sobre una instalación de fabricación de gránulo atomizado considerando las operaciones de recepción, gestión y almacenamiento de materias primas.

Species distributed across wide elevational gradients are likely to experience local thermal adaptation and exhibit high thermal plasticity, as these gradients are characterised by steep environmental changes over short geographic distances (i.e., strong selection differentials). The prevalence of adaptive intraspecific variation in thermal tolerance with elevation remains unclear, however, particularly in freshwater taxa. We explored variation in upper and lower thermal limits and acclimation capacity among Iberian populations of adults of the widespread water beetle Agabus bipustulatus (Dytiscidae) across a 2000 m elevational gradient, from lowland to alpine areas. Since mean and extreme temperatures decline with elevation, we predicted that populations at higher elevations will show lower heat tolerance and higher cold tolerance than lowland ones. We also explored whether acclimation capacity is positively related with climatic variability across elevations. We found significant variation in thermal limits between populations of A. bipustulatus, but no evidence of local adaptation to different thermal conditions across the altitudinal gradient, as relationships between thermal limits and elevation or climatic variables were largely nonsignificant. Furthermore, plasticities of both upper and lower thermal limits were consistently low in all populations. These results suggest thermal niche conservatism in this species, likely due to gene flow counteracting the effects of divergent selection, or adaptations in other traits that buffer exposure to climate extremes. The limited adaptive potential and plasticity of thermal tolerance observed in A. bipustulatus suggest that even generalist species, distributed across wide environmental gradients, may have limited resilience to global warming., (© 2024 Institute of Zoology, Chinese Academy of Sciences.)

An intricate interplay between evolutionary and demographic processes has frequently resulted in complex patterns of genetic and phenotypic diversity in alpine lineages, posing serious challenges to species delimitation and biodiversity conservation planning. Here we integrate genomic data, geometric morphometric analyses and thermal tolerance experiments to explore the role of Pleistocene climatic changes and adaptation to alpine environments on patterns of genomic and phenotypic variation in diving beetles from the taxonomically complex Agabus bipustulatus species group. Genetic structure and phylogenomic analyses revealed the presence of three geographically cohesive lineages, two representing trans-Palearctic and Iberian populations of the elevation-generalist A. bipustulatus and another corresponding to the strictly-alpine A. nevadensis, a narrow-range endemic taxon from the Sierra Nevada mountain range in southeastern Iberia. The best-supported model of lineage divergence, along with the existence of pervasive genetic introgression and admixture in secondary contact zones, is consistent with a scenario of population isolation and connectivity linked to Quaternary climatic oscillations. Our results suggest that A. nevadensis is an alpine ecotype of A. bipustulatus, whose genotypic, morphological and physiological differentiation likely resulted from an interplay between population isolation and local altitudinal adaptation. Remarkably, within the Iberian Peninsula, such ecotypic differentiation is unique to Sierra Nevada populations and has not been replicated in other alpine populations of A. bipustulatus. Collectively, our study supports fast ecotypic differentiation and incipient speciation processes within the study complex and points to Pleistocene glaciations and local adaptation along elevational gradients as key drivers of biodiversity generation in alpine environments., (© 2024 The Author(s). Molecular Ecology published by John Wiley & Sons Ltd.)

Introduction: Postoperative exercise improves arteriovenous fistula maturation for hemodialysis. However, scarce evidence exists about hand grip device on fistula maturation process., Objective: To evaluate the efficacy of a hand grip training program on arteriovenous fistula maturation in population with Chronic Kidney Disease 5-5D., Methodology: Prospective study (15 months). Patients were randomized to handgrip (HG) or control group (CG) postoperatively. HG performed a training program using a hand grip device. CG received conventional care. Upper limb muscle strength (ULMS), Duplex ultrasonography, and clinical arteriovenous fistula maturation were assessed at 4 and 8 weeks postoperatively., Results: At 8 weeks after fistula creation, upper limb muscle strength was increased only in the handgrip group (from 18 ± 6 to 23 ± 9 kg, p  = 0.023). Clinical maturation was significantly greater in handgrip group versus control group, both at 4 weeks after intervention (62% vs 23%, p  = 0.004) and at 8 weeks (65% vs 27%, p  = 0.004). Similarly, the Doppler ultrasonography maturation rates were significantly greater in the HG, both at 4 weeks (HG: 84% vs CG: 47%; p  = 0.004) and at 8 weeks (HG: 89% vs CG: 50%; p  = 0.002)., Conclusions: The hand grip is a useful and safety training device to improve the arteriovenous fistula maturation. This device results a new therapeutic option for maturation in arteriovenous fistula, particularly in distal arteriovenous fistula. Further studies are required to support these results., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

The climatic variability hypothesis (CVH) predicts that organisms in more thermally variable environments have wider thermal breadths and higher thermal plasticity than those from more stable environments. However, due to evolutionary trade-offs, taxa with greater absolute thermal limits may have little plasticity of such limits (trade-off hypothesis). The CVH assumes that climatic variability is the ultimate driver of thermal tolerance variation across latitudinal and altitudinal gradients, but average temperature also varies along such gradients. We explored intraspecific variation of thermal tolerance in three typical Mediterranean saline water beetles (families Hydrophilidae and Dytiscidae). For each species, we compared two populations where the species coexist, with similar annual mean temperature but contrasting thermal variability (continental vs. coastal population). We estimated thermal limits of adults from each population, previously acclimated at 17, 20, or 25 °C. We found species-specific patterns but overall, our results agree with the CVH regarding thermal ranges, which were wider in the continental (more variable) population. In the two hydrophilid species, this came at the cost of losing plasticity of the upper thermal limit in this population, supporting the trade-off hypothesis, but not in the dytiscid one. Our results support the role of local adaptation to thermal variability and trade-offs between basal tolerance and physiological plasticity in shaping thermal tolerance in aquatic ectotherms, but also suggest that intraspecific variation of thermal tolerance does not fit a general pattern among aquatic insects. Overlooking such intraspecific variation could lead to inaccurate predictions of the vulnerability of aquatic insects to global warming., (© 2023 The Authors. Insect Science published by John Wiley & Sons Australia, Ltd on behalf of Institute of Zoology, Chinese Academy of Sciences.)

Subterranean ecosystems (comprising terrestrial, semi-aquatic, and aquatic components) are increasingly threatened by human activities; however, the current network of surface-protected areas is inadequate to safeguard subterranean biodiversity. Establishing protected areas for subterranean ecosystems is challenging. First, there are technical obstacles in mapping three-dimensional ecosystems with uncertain boundaries. Second, the rarity and endemism of subterranean organisms, combined with a scarcity of taxonomists, delays the accumulation of essential biodiversity knowledge. Third, establishing agreements to preserve subterranean ecosystems requires collaboration among multiple actors with often competing interests. This perspective addresses the challenges of preserving subterranean biodiversity through protected areas. Even in the face of uncertainties, we suggest it is both timely and critical to assess general criteria for subterranean biodiversity protection and implement them based on precautionary principles. To this end, we examine the current status of European protected areas and discuss solutions to improve their coverage of subterranean ecosystems., (© 2024. The Author(s).)

Subterranean ecosystems are among the most widespread environments on Earth, yet we still have poor knowledge of their biodiversity. To raise awareness of subterranean ecosystems, the essential services they provide, and their unique conservation challenges, 2021 and 2022 were designated International Years of Caves and Karst. As these ecosystems have traditionally been overlooked in global conservation agendas and multilateral agreements, a quantitative assessment of solution-based approaches to safeguard subterranean biota and associated habitats is timely. This assessment allows researchers and practitioners to understand the progress made and research needs in subterranean ecology and management. We conducted a systematic review of peer-reviewed and grey literature focused on subterranean ecosystems globally (terrestrial, freshwater, and saltwater systems), to quantify the available evidence-base for the effectiveness of conservation interventions. We selected 708 publications from the years 1964 to 2021 that discussed, recommended, or implemented 1,954 conservation interventions in subterranean ecosystems. We noted a steep increase in the number of studies from the 2000s while, surprisingly, the proportion of studies quantifying the impact of conservation interventions has steadily and significantly decreased in recent years. The effectiveness of 31% of conservation interventions has been tested statistically. We further highlight that 64% of the reported research occurred in the Palearctic and Nearctic biogeographic regions. Assessments of the effectiveness of conservation interventions were heavily biased towards indirect measures (monitoring and risk assessment), a limited sample of organisms (mostly arthropods and bats), and more accessible systems (terrestrial caves). Our results indicate that most conservation science in the field of subterranean biology does not apply a rigorous quantitative approach, resulting in sparse evidence for the effectiveness of interventions. This raises the important question of how to make conservation efforts more feasible to implement, cost-effective, and long-lasting. Although there is no single remedy, we propose a suite of potential solutions to focus our efforts better towards increasing statistical testing and stress the importance of standardising study reporting to facilitate meta-analytical exercises. We also provide a database summarising the available literature, which will help to build quantitative knowledge about interventions likely to yield the greatest impacts depending upon the subterranean species and habitats of interest. We view this as a starting point to shift away from the widespread tendency of recommending conservation interventions based on anecdotal and expert-based information rather than scientific evidence, without quantitatively testing their effectiveness., (© 2022 The Authors. Biological Reviews published by John Wiley & Sons Ltd on behalf of Cambridge Philosophical Society.)

The climatic variability hypothesis predicts the evolution of species with wide thermal tolerance ranges in environments with variable temperatures, and the evolution of thermal specialists in thermally stable environments. In caves, the extent of spatial and temporal thermal variability experienced by taxa decreases with their degree of specialization to deep subterranean habitats. We use phylogenetic generalized least squares to model the relationship among thermal tolerance (upper lethal limits), subterranean specialization (estimated using ecomorphological traits), and habitat temperature in 16 beetle species of the tribe Leptodirini (Leiodidae). We found a significant, negative relationship between thermal tolerance and the degree of subterranean specialization. Conversely, habitat temperature had only a marginal effect on lethal limits. In agreement with the climatic variability hypothesis and under a climate change context, we show that the specialization process to live in deep subterranean habitats involves a reduction of upper lethal limits, but not an adjustment to habitat temperature. Thermal variability seems to exert a higher evolutionary pressure than mean habitat temperature to configure the thermal niche of subterranean species. Our results provide novel insights on thermal physiology of species with poor dispersal capabilities and on the evolutionary process of adaptation to subterranean environments. We further emphasize that the pathways determining vulnerability of subterranean species to climate change greatly depend on the degree of specialization to deep subterranean environments., (© 2022 The Ecological Society of America.)

Thermal history can plastically alter the response of ectotherms to temperature, and thermal performance curves (TPCs) are powerful tools for exploring how organismal-level performance varies with temperature. Plasticity in TPCs may be favoured in thermally variable habitats, where it can result in fitness benefits. However, thermal physiology remains insufficiently studied for freshwater insects despite freshwater biodiversity being at great risk under global change. Here, we assess how acclimation at either summer or winter average temperatures changes TPCs for locomotion activity and metabolism in Enochrus jesusarribasi (Hydrophilidae), a water beetle endemic to shallow saline streams in SE Spain. This beetle is a bimodal gas exchanger and so we also assessed how aerial and aquatic gas exchange varied across temperatures for both acclimation treatments. Responses of locomotory TPCs to thermal acclimation were relatively weak, but high temperature acclimated beetles tended to exhibit higher maximum locomotor activity and reduced TPC breadth than those acclimated at lower temperature. High temperature acclimation increased the thermal sensitivity of metabolic rates, contrary to the response generally found in aquatic organisms. Higher metabolic rates upon high temperature acclimation were achieved by increasing aerial, rather than aquatic oxygen uptake. Such plastic respiratory behaviour likely contributed to enhanced locomotor performance at temperatures around the optimum and thermal plasticity could thus be an important component in the response of aquatic insects to climate change. However, high temperature acclimation appeared to be detrimental for locomotion in subsequent exposure at upper sublethal temperatures, suggesting that this narrow range endemic may be vulnerable to future climate warming. This study demonstrates that TPCs are context-specific, differing with performance metric as well as thermal history. Such context dependency must be considered when using TPCs to predict organismal responses to climate change., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)

This study addresses the concentration of particulate matter and their size using a statistical analysis of data obtained inside seven schools located in the towns of Castellón (S1, S2, and S3), Alcora (S4, S5, and S6) and Lucena (S7) in northeast Spain. Samples were taken for five to eight hours, depending on school hours, to obtain a monthly sample for each school. The main goal of this study is to assess the differences depending on the type of location and the sampling point to be able to design corrective measures that improve the habitability and safety of the teaching spaces analyzed. The lowest concentrations of fine particulate matter, less than 2.5 µm, were registered at the rural location. The values of these particles found in industrial and urban locations were not substantially different. In the case of particulate matter between 2.5 and 10 µm, significant differences were observed between the three types of locations. The lowest concentrations of particles larger than 10 µm were registered at the rural location, and the highest concentrations were found at the industrial locations. Among the urban stations, the particle concentration of this fraction in station S2 was significantly higher than that in stations S1 and S3, which had similar concentrations. These values are also similar to those registered at school S6, which is at an industrial location. The resuspension of particles from both indoor sources as well as those transported from the outside is an important factor in the concentrations of particles inside classrooms.

In the context of aridification in Mediterranean regions, desiccation resistance and physiological plasticity will be key traits for the persistence of aquatic insects exposed to increasing desiccation stress. Control of cuticular transpiration through changes in the quantity and composition of epicuticular hydrocarbons (CHCs) is one of the main mechanisms of desiccation resistance in insects, but it remains largely unexplored in aquatic ones. We studied acclimation responses to desiccation in adults of two endemic water beetles from distant lineages living in Mediterranean intermittent saline streams: Enochrus jesusarribasi (Hydrophilidae) and Nebrioporus baeticus (Dytiscidae). Cuticular water loss and CHC composition were measured in specimens exposed to a prior non-lethal desiccation stress, allowed to recover and exposed to a subsequent desiccation treatment. E. jesusarribasi showed a beneficial acclimation response to desiccation: pre-desiccated individuals reduced cuticular water loss rate in a subsequent exposure by increasing the relative abundance of cuticular methyl-branched compounds, longer chain alkanes and branched alkanes. In contrast, N. baeticus lacked acclimation capacity for controlling water loss and therefore may have a lower physiological capacity to cope with increasing aridity. These results are relevant to understanding biochemical adaptations to drought stress in inland waters in an evolutionary and ecological context.

Accurate assessments of species vulnerability to climate change need to consider the physiological capacity of organisms to deal with temperature changes and identify early signs of thermally induced stress. Oxidative stress biomarkers and acetylcholinesterase activity are useful proxies of stress at the cellular and nervous system level. Such responses are especially relevant for poor dispersal organisms with limited capacity for behavioural thermoregulation, like deep subterranean species. We combined experimental measurements of upper lethal thermal limits, acclimation capacity and biomarkers of oxidative stress and neurotoxicity to assess the impact of heat stress (20°C) at different exposure times (2 and 7 days) on the Iberian endemic subterranean beetle Parvospeonomus canyellesi . Survival response (7 days of exposure) was similar to that reported for other subterranean specialist beetles (high survival up to 20°C but no above 23°C). However, a low physiological plasticity (i.e. incapacity to increase heat tolerance via acclimation) and signs of impairment at the cellular and nervous system level were observed after 7 days of exposure at 20°C. Such sublethal effects were identified by significant differences in total antioxidant capacity, glutathione S-transferase activity, the ratio of reduced to oxidized forms of glutathione and acetylcholinesterase activity between the control (cave temperature) and 20°C treatment. At 2 days of exposure, most biomarker values indicated some degree of oxidative stress in both the control and high-temperature treatment, likely reflecting an initial altered physiological status associated to factors other than temperature. Considering these integrated responses and the predicted increase in temperature in its unique locality, P. canyellesi would have a narrower thermal safety margin to face climate change than that obtained considering only survival experiments. Our results highlight the importance of exploring thermally sensitive processes at different levels of biological organization to obtain more accurate estimates of the species capacity to face climate change., (© The Author(s) 2020. Published by Oxford University Press and the Society for Experimental Biology.)

This paper focuses on a study of fine (less than 2.5 µm) airborne particles collected inside seven primary schools located on a coastal Mediterranean area which has a significant industrial hub for the processing of clays and other minerals as raw materials. Of the seven schools, three are located in an urban area 20 km away from the main industrial hub, three are in a town located next to the industrial estate, and one is in a rural location, 30 km from the industrial area. The objective of this study is to identify the main types of particles found in the three examined environments. The particle matter identified in the fine particle samples is grouped into three main groups: mineral compounds, particles from combustion processes and phases emitted in high-temperature industrial processes. The mineral particles, which can come from natural or anthropogenic emissions, have been classified depending on their morphology as isometric allotriomorphs or subidiomorphs, with a tabular habit; acicular forms; or pure crystalline forms. Compounds from combustion processes have two types of morphologies: spheroid and dendritic soot particles. Additionally, in smaller quantities, spherical particles associated with high-temperature industrial processes, such as the emissions of ceramic tile-firing and frit-melting processes, are identified. A summary table is shown, which lists the characteristics, as well as the most significant origin of the main particles identified in the fine (<2.5 μm) airborne particles collected inside primary schools located in three different environments (urban, industrial and rural). A visual scale has been established based on the number of particles observed in the samples of the atmospheric particulate fraction between the sizes of 2.5 and 10 µm collected inside the schools. The ratios Ca/Si, S/Si, S/Ca and (Si+Ca)/S have been established. Results obtained may be useful in epidemiological studies in the ceramic cluster area in order to estimate children's exposure to different indoor primary school microenvironments. Effective policies and mitigation measurements for the protection of children's health should be carried out in this highly industrialized area.

Cave-dwelling ectotherms, which have evolved for millions of years under stable thermal conditions, could be expected to have adjusted their physiological limits to the narrow range of temperatures they experience and to be highly vulnerable to global warming. However, most of the few existing studies on thermal tolerance in subterranean invertebrates highlight that despite the fact that they show lower heat tolerance than most surface-dwelling species, their upper thermal limits are generally not adjusted to ambient temperature. The question remains to what extent this pattern is common across subterranean invertebrates. We studied basal heat tolerance and its plasticity in four species of distant arthropod groups (Coleoptera, Diplopoda, and Collembola) with different evolutionary histories but under similar selection pressures, as they have been exposed to the same constant environmental conditions for a long time. Adults were exposed at different temperatures for 1 week to determine upper lethal temperatures. Then, individuals from previous sublethal treatments were transferred to a higher temperature to determine acclimation capacity. Upper lethal temperatures of three of the studied species were similar to those reported for other subterranean species (between 20 and 25°C) and widely exceeded the cave temperature (13-14°C). The diplopod species showed the highest long-term heat tolerance detected so far for a troglobiont (i.e., obligate subterranean) species (median lethal temperature after 7 days exposure: 28°C) and a positive acclimation response. Our results agree with previous studies showing that heat tolerance in subterranean species is not determined by environmental conditions. Thus, subterranean species, even those living under similar climatic conditions, might be differently affected by global warming., Competing Interests: The authors have no competing interest to declare., (© 2019 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

PM10 levels and its chemical composition were studied inside and outdoor of seven primary schools (3 in urban environment, 3 in industrial environment, 1 in rural environment) located in the Mediterranean coast in an area with an important industrial nucleus dedicated to the treatment of raw mineral materials. The main objective of this work is a comparison between these levels obtained inside and outside schools and also asses the influence of various natural and anthropogenic emission sources on particles concentrations found inside. The indoor airborne samples were collected using RespiCon TM. In the three outdoor sampling stations was used a minivol air sampler type 3.1 LVS of Derenda. PM10 Chemical composition was obtained by ICP-MS (elements) and ion chromatography The ratio I/O (indoor/outdoor) has been calculated taking into account only the samples taken in the same conditions. In all schools the ratio I/O for PM10 was greater than unity (between 1.3 and 7.8), indicating that existed significant indoor sources of these particles. In the three schools located in the industrial environment were collected PM10 samples inside and outside in non-teaching periods. Comparing the values of I/O when the classrooms were unoccupied with respect to the average value of these same schools when the classrooms are occupied, the behaviour is different depending on the location. On the other hand, a sample in an industrial school was obtained when some infrastructure works were being carried out outside of school. This caused a significant increase in the concentration of particles in the interior (I/O = 19.9). From the levels of As, Ni, Cd, Pb, Al, B, Zn, Mg, Sb, F - , ClO 2- , NO 3- and SO 4 2- in PM10 inside and outside of each school, also the ratios I/O were calculated. These chemical ratios I/O were higher than unity in all cases and generally higher than those recorded in the case of PM10. Finally, Pearson correlation coefficients (r) between the elements and anions and the PM10, and between the different elements and anions were calculated for the purpose of establishing the existence of common emission sources.

Salinity tolerance has enabled the colonization of inland saline waters and promoted species diversification in some lineages of aquatic insects. However, the mechanisms behind this tolerance, particularly the role of cuticle hydrocarbons (CHCs), are not well-known. We characterized the CHC profile of eight species of two water beetle genera (Nebrioporus, Adephaga: Dytiscidae and Enochrus, Polyphaga: Hydrophilidae), which span the fresh-hypersaline gradient, to: i) determine the interspecific variation of CHC composition in relation to species' salinity tolerance; ii) explore plastic adjustments in CHC profiles in response to salinity changes at the intraspecific level in saline-tolerant species. CHC profiles were highly species-specific, more complex and diverse in composition, and characterized by longer-chain-length compounds in the species with higher salinity tolerance within each genus. Higher salinity tolerance in the Enochrus species was also associated with an increase in the relative abundance of branched alkanes, and with a lower proportion of n-alkanes and unsaturated compounds. These CHC characteristics are related with improved waterproofing capacity and suggest that reducing cuticle permeability was one of the key mechanisms to adapt to saline waters. Similar CHC composition patterns were found at the intraspecific level between populations from lower and higher salinity sites within saline-tolerant species of each genus. These saline species also displayed an extraordinary ability to adjust CHC profiles to changing salinity conditions in the laboratory in a relatively short time, which reflects great plasticity and a high potential to deal with daily and seasonal environmental fluctuations in the highly dynamic saline habitats., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Under global change, the ion concentration of aquatic ecosystems is changing worldwide. Many freshwater ecosystems are being salinized by anthropogenic salt inputs, whereas many naturally saline ones are being diluted by agricultural drainages. This occurs concomitantly with changes in other stressors, which can result in additive, antagonistic or synergistic effects on organisms. We reviewed experimental studies that manipulated salinity and other abiotic stressors, on inland and transitional aquatic habitats, to (i) synthesize their main effects on organisms' performance, (ii) quantify the frequency of joint effect types across studies and (iii) determine the overall individual and joint effects and their variation among salinity-stressor pairs and organism groups using meta-analyses. Additive effects were slightly more frequent (54%) than non-additive ones (46%) across all the studies ( n = 105 responses). However, antagonistic effects were dominant for the stressor pair salinity and toxicants (44%, n = 43), transitional habitats (48%, n = 31) and vertebrates (71%, n = 21). Meta-analyses showed detrimental additive joint effects of salinity and other stressors on organism performance and a greater individual impact of salinity than the other stressors. These results were consistent across stressor pairs and organism types. These findings suggest that strategies to mitigate multiple stressor impacts on aquatic ecosystems should prioritize restoring natural salinity concentrations.This article is part of the theme issue 'Salt in freshwaters: causes, ecological consequences and future prospects'., (© 2018 The Author(s).)

Considering how organisms adapt to stress is essential if we are to anticipate biological responses to global change in ecosystems. Communities in stressful environments can potentially be assembled by specialists (i.e. species that only occur in a limited range of environmental conditions) and/or generalist species with wider environmental tolerances. We review the existing literature on the salinity tolerance of aquatic insects previously identified as saline specialists because they were exclusively found in saline habitats, and explore if these saline realized niche specialists are also specialists in their fundamental niches or on the contrary are fundamental niche generalist species confined to the highest salinities they can tolerate. The results suggest that species inhabiting saline waters are generalists in their fundamental niches, with a predominant pattern of high survival in freshwater-low salinity conditions, where their fitness tends to be similar or even higher than in saline waters. Additionally, their performance in freshwater tends to be similar to related strictly freshwater species, so no apparent trade-off of generalization is shown. These results are discussed in the framework of the ecological and evolutionary processes driving community assembly across the osmotic stress gradient, and their potential implications for predicting impacts from saline dilution and freshwater salinization.This article is part of the theme issue 'Salt in freshwaters: causes, ecological consequences and future prospects'., (© 2018 The Author(s).)

Transitions from fresh to saline habitats are restricted to a handful of insect lineages, as the colonization of saline waters requires specialized mechanisms to deal with osmotic stress. Previous studies have suggested that tolerance to salinity and desiccation could be mechanistically and evolutionarily linked, but the temporal sequence of these adaptations is not well established for individual lineages. We combined molecular, physiological and ecological data to explore the evolution of desiccation resistance, hyporegulation ability (i.e., the ability to osmoregulate in hyperosmotic media) and habitat transitions in the water beetle genus Enochrus subgenus Lumetus (Hydrophilidae). We tested whether enhanced desiccation resistance evolved before increases in hyporegulation ability or vice versa, or whether the two mechanisms evolved in parallel. The most recent ancestor of Lumetus was inferred to have high desiccation resistance and moderate hyporegulation ability. There were repeated shifts between habitats with differing levels of salinity in the radiation of the group, those to the most saline habitats generally occurring more rapidly than those to less saline ones. Significant and accelerated changes in hyporegulation ability evolved in parallel with smaller and more progressive increases in desiccation resistance across the phylogeny, associated with the colonization of meso- and hypersaline waters during global aridification events. All species with high hyporegulation ability were also desiccation-resistant, but not vice versa. Overall, results are consistent with the hypothesis that desiccation resistance mechanisms evolved first and provided the physiological basis for the development of hyporegulation ability, allowing these insects to colonize and diversify across meso- and hypersaline habitats., (© 2017 John Wiley & Sons Ltd.)

Hydrocarbons are the principal component of insect cuticle and play an important role in maintaining water balance. Cuticular impermeability could be an adaptative response to salinity and desiccation in aquatic insects; however, cuticular hydrocarbons have been poorly explored in this group and there are no previous data on saline species. We characterized cuticular hydrocarbons of adults and larvae of two saline aquatic beetles, namely Nebrioporus baeticus (Dytiscidae) and Enochrus jesusarribasi (Hydrophilidae), using a gas chromatograph coupled to a mass spectrometer. The CHC profile of adults of both species, characterized by a high abundance of branched alkanes and low of unsaturated alkenes, seems to be more similar to that of some terrestrial beetles (e.g., desert Tenebrionidae) compared with other aquatic Coleoptera (freshwater Dytiscidae). Adults of E. jesusarribasi had longer chain compounds than N. baeticus , in agreement with their higher resistance to salinity and desiccation . The more permeable cuticle of larvae was characterized by a lower diversity in compounds, shorter carbon chain length and a higher proportion of unsaturated hydrocarbons compared with that of the adults. These results suggest that osmotic stress on aquatic insects could exert a selection pressure on CHC profile similar to aridity in terrestrial species., Competing Interests: The authors declare there are no competing interests.

Exposing organisms to a particular stressor may enhance tolerance to a subsequent stress, when protective mechanisms against the two stressors are shared. Such cross-tolerance is a common adaptive response in dynamic multivariate environments and often indicates potential co-evolution of stress traits. Many aquatic insects in inland saline waters from Mediterranean-climate regions are sequentially challenged with salinity and desiccation stress. Thus, cross-tolerance to these physiologically similar stressors could have been positively selected in insects of these regions. We used adults of the saline water beetles Enochrus jesusarribasi (Hydrophilidae) and Nebrioporus baeticus (Dytiscidae) to test cross-tolerance responses to desiccation and salinity. In independent laboratory experiments, we evaluated the effects of (i) salinity stress on the subsequent resistance to desiccation and (ii) desiccation stress (rapid and slow dehydration) on the subsequent tolerance to salinity. Survival, water loss and haemolymph osmolality were measured. Exposure to stressful salinity improved water control under subsequent desiccation stress in both species, with a clear cross-tolerance (enhanced performance) in N. baeticus In contrast, general negative effects on performance were found under the inverse stress sequence. The rapid and slow dehydration produced different water loss and haemolymph osmolality dynamics that were reflected in different survival patterns. Our finding of cross-tolerance to salinity and desiccation in ecologically similar species from distant lineages, together with parallel responses between salinity and thermal stress previously found in several aquatic taxa, highlights the central role of adaption to salinity and co-occurring stressors in arid inland waters, having important implications for the species' persistence under climate change., (© 2017. Published by The Company of Biologists Ltd.)

Background: Desiccation resistance shapes the distribution of terrestrial insects at multiple spatial scales. However, responses to drying stress have been poorly studied in aquatic groups, despite their potential role in constraining their distribution and diversification, particularly in arid and semi-arid regions., Methods: We examined desiccation resistance in adults of four congeneric water beetle species (Enochrus, family Hydrophilidae) with contrasting habitat specificity (lentic vs. lotic systems and different salinity optima from fresh- to hypersaline waters). We measured survival, recovery capacity and key traits related to desiccation resistance (fresh mass, % water content, % cuticle content and water loss rate) under controlled exposure to desiccation, and explored their variability within and between species., Results: Meso- and hypersaline species were more resistant to desiccation than freshwater and hyposaline ones, showing significantly lower water loss rates and higher water content. No clear patterns in desiccation resistance traits were observed between lotic and lentic species. Intraspecifically, water loss rate was positively related to specimens' initial % water content, but not to fresh mass or % cuticle content, suggesting that the dynamic mechanism controlling water loss is mainly regulated by the amount of body water available., Discussion: Our results support previous hypotheses suggesting that the evolution of desiccation resistance is associated with the colonization of saline habitats by aquatic beetles. The interespecific patterns observed in Enochrus also suggest that freshwater species may be more vulnerable than saline ones to drought intensification expected under climate change in semi-arid regions such as the Mediterranean Basin., Competing Interests: The authors declare that there are no competing interests.

A better knowledge of the physiological basis of salinity tolerance is essential to understanding the ecology and evolutionary history of organisms that have colonized inland saline waters. Coleoptera are amongst the most diverse macroinvertebrates in inland waters, including saline habitats; however, the osmoregulatory strategies they employ to deal with osmotic stress remain unexplored. Survival and haemolymph osmotic concentration at different salinities were examined in adults of eight aquatic beetle species which inhabit different parts of the fresh-hypersaline gradient. Studied species belong to two unrelated genera which have invaded saline waters independently from freshwater ancestors; Nebrioporus (Dytiscidae) and Enochrus (Hydrophilidae). Their osmoregulatory strategy (osmoconformity or osmoregulation) was identified and osmotic capacity (the osmotic gradient between the animal's haemolymph and the external medium) was compared between species pairs co-habiting similar salinities in nature. We show that osmoregulatory capacity, rather than osmoconformity, has evolved independently in these different lineages. All species hyperegulated their haemolymph osmotic concentration in diluted waters; those living in fresh or low-salinity waters were unable to hyporegulate and survive in hyperosmotic media (> 340 mosmol kg(-1)). In contrast, the species which inhabit the hypo-hypersaline habitats were effective hyporegulators, maintaining their haemolymph osmolality within narrow limits (ca. 300 mosmol kg(-1)) across a wide range of external concentrations. The hypersaline species N. ceresyi and E. jesusarribasi tolerated conductivities up to 140 and 180 mS cm(-1), respectively, and maintained osmotic gradients over 3500 mosmol kg(-1), comparable to those of the most effective insect osmoregulators known to date. Syntopic species of both genera showed similar osmotic capacities and in general, osmotic responses correlated well with upper salinity levels occupied by individual species in nature. Therefore, osmoregulatory capacity may mediate habitat segregation amongst congeners across the salinity gradient.

Background: Kidney stones have become increasingly prevalent in the developed countries over the past 100 years. The incidence of urolithiasis in a population depends on the geographical area, racial distribution, socio-economic status and dietary habits. During the past decades, these factors have changed affecting the incidence and also the chemical composition of calculi; nowadays in our region, the most common stones composition is calcium oxalate. The identification of the calculi composition enables superior treatment, lower (decreased) cost and a better quality of life for the patients., Methods: We analyzed the composition and the evolution of all of the cases concerning calculi received at Biochemical Clinical Analysis Laboratory from 2007 to 2010, using Interferometry with Fourier transformation (FTIR). The relationship between composition, gender and age was studied for an aleatory group in 2010 (n=657, 431 men and 226 women)., Results: The stone composition obtained was mixtures 24.7% and only one component 75.3%. Calcium oxalate monohydrate (COM) 41.5%, calcium oxalate dihydrate (COD) 7.6%, anhydrous uric acid (AUA) 12.4%, uric acid dehydrate (UAD) 6.7%, urates 1.4%, carbonate-apatite (CA) 2.9%, and others 2.8%. The male to female ratio was 1.9 and the largest number of stones was found in patients between the ages of 40 and 49, for both men and women., Conclusions: The most common composition (relative percentage) was COM, mixtures and AUA. Presence of calculi is more common in men than in women with the exception of carbonate apatite stones. Stones follow a Gaussian distribution throughout the lifetime of a patient, with particular incidence in those between 40 to 49 years old.