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A significant fraction of Earth's ecosystems undergoes periodic wet‐dry alternating transitional states. These globally distributed water‐driven transitional ecosystems, such as intermittent rivers and coastal shorelines, have traditionally been studied as two distinct entities, whereas they constitute a single, interconnected meta‐ecosystem. This has resulted in a poor conceptual and empirical understanding of water‐driven transitional ecosystems. Here, we develop a conceptual framework that places the temporal availability of water as the core driver of biodiversity and functional patterns of transitional ecosystems at the global scale. Biological covers (e.g., aquatic biofilms and biocrusts) serve as an excellent model system thriving in both aquatic and terrestrial states, where their succession underscores the intricate interplay between these two states. The duration, frequency, and rate of change of wet‐dry cycles impose distinct plausible scenarios where different types of biological covers can occur depending on their desiccation/hydration resistance traits. This implies that the distinct eco‐evolutionary potential of biological covers, represented by their trait profiles, would support different functions while maintaining similar multifunctionality levels. By embracing multiple alternating transitional states as interconnected entities, our approach can help to better understand and manage global change impacts on biodiversity and multifunctionality in water‐driven transitional ecosystems, while providing new avenues for interdisciplinary studies. [ABSTRACT FROM AUTHOR]

Microbial biodiversity is fundamental to maintain ecosystem functioning in seasonally variable ecosystems. However, it remains unclear how alterations in water availability caused by episodic drying compromise the ability of stream microbes to maintain multiple functions simultaneously (e.g., primary production and carbon cycling). Using data from 32 streams, we investigated how the phenology of annual drying influences stream sediment microbial biodiversity and their capacity to sustain multifunctionality. Our results showed that stream multifunctionality and most bacteria did not respond to changes in drying phenology. Only two bacterial groups, the drying‐resistant Sphingobacteriia and the drying‐sensitive Acidobacteria_Gp7, exhibited positive associations with multifunctionality; whereas, bacterial diversity showed a negative correlation with functions. Among these biodiversity aspects, Sphingobacteriia showed the strongest capacity to maintain multifunctionality at low and moderate performance levels. Our findings will help to better understand the mechanisms through which biodiversity sustains the functioning of seasonally variable streams and their responses to global change. [ABSTRACT FROM AUTHOR]

Aquatic fungi are highly diverse organisms that play a critical role in global biogeochemical cycles. Yet it remains unclear which assembly processes determine their co-occurrence and assembly patterns over gradients of drying intensity, which is a common stressor in fluvial networks. Although aquatic fungi possess drying-specific adaptations, little is known about how functional similarity influences co-occurrence probability and which functional traits are sorted by drying. Using field data from 15 streams, we investigated how co-occurrence patterns and assembly processes responded to drying intensity. To do so, we determined fungal co-occurrence patterns, functional traits that best explain species co-occurrence likelihood, and community assembly mechanisms explaining changes in functional diversity over the drying gradient. Our results identified 24 species pairs with positive co-occurrence probabilities and 16 species pairs with negative associations. The co-occurrence probability was correlated with species differences in conidia shape and fungal endophytic capacity. Functional diversity reduction over the drying gradient is generally associated with non-random abiotic filtering. However, the assembly processes changed over the drying gradient, with random assembly prevailing at low drying intensity and abiotic filtering gaining more importance as drying intensifies. Collectively, our results can help anticipate the impacts of global change on fungal communities and ecosystem functioning. [ABSTRACT FROM AUTHOR]

Biocrusts are major contributors to dryland diversity, functioning, and services. However, little is known about how habitat degradation will impact multiple facets of biocrust diversity and measurable functional traits. We evaluated changes in taxonomic, functional, and phylogenetic diversity of biocrust‐forming lichens along a habitat degradation gradient related to the presence of linear infrastructure (i.e., a road) and a profound agricultural driven transformation. To do so, we selected 50 remnants of a Mediterranean shrubland. We considered several surrogates of habitat quality and causal disturbance on the various diversity facets of biocrusts by using structural equation modeling, hypothesizing that habitat degradation primarily affects functional diversity, which in turn regulates changes in taxonomic and phylogenetic diversities, and also that taxonomic and phylogenetic diversities are coupled. Fragment connectivity, distance to linear infrastructure (i.e., a road) and, particularly, soil fertility (i.e., soil P concentration), had mostly negative effects on biocrust functional diversity, which in turn affected both taxonomic and phylogenetic diversities. However, we found no direct effects of habitat degradation variables on the taxonomic and phylogenetic diversities. We also found that increases in phylogenetic diversity had a positive effect on taxonomic diversity along the habitat degradation gradient. Our results indicate that functional diversity of biocrusts is strongly affected by habitat degradation, which may profoundly alter their contribution to ecosystem functioning and services. Furthermore, functional diversity regulates the response of biocrust taxonomic and phylogenetic diversity to habitat degradation. These findings indicate that habitat degradation alters and simplifies the diversity of functional traits of biocrust‐forming lichens, leading to biodiversity loss, with important consequences for the conservation of global drylands biodiversity. [ABSTRACT FROM AUTHOR]

Assessing the response of biological communities to contrasting environmental conditions is crucial to predict the effects of global change drivers. The influence of multiple environmental factors may differ depending on the diversity facet considered, which emphasizes the need to simultaneously evaluate the functional (FD), phylogenetic (PD) and taxonomic (TD) diversity.To examine how these facets of biodiversity respond to environmental changes, we studied lichen epiphytic communities across 47 beech forest fragments from two biogeographic regions. We applied structural equation modelling to relate habitat fragmentation, climate and habitat quality with FD, PD and TD. We compared the community response to contrasting climatic conditions by analysing independently Atlantic and Mediterranean communities.We found different major drivers of biodiversity patterns across biogeographic regions. Habitat fragmentation performed the highest effect on lichen communities, with a reduction of FD, PD and TD at both regions. However, the influence of climate was stronger in the Atlantic region than in the Mediterranean region, where the effect of habitat quality was superior. The effect of the environmental predictors over PD and TD was both direct and indirect through the different components of FD, and their intensity and sign differed across regions. Changes in PD were not related to changes in TD.Synthesis. Our results evidenced that the major environmental drivers affecting epiphytic communities were geographically structured. These drivers modified the diversity of the epiphytic community directly but also indirectly through changes in FD, which emerged as a causal but not unique determinant of PD and TD. Our findings also showed the difficulty for inferring TD through PD. These results emphasize the essential role of FD predicting part of the response of lichen communities to global change drivers but also highlight the importance of considering multiple biodiversity facets to understand the effects of environmental change on community structure. [ABSTRACT FROM AUTHOR]

Little is known about the life cycle of Rhembobius parasitoids (Hymenoptera: Ichneumonidae). Known host records are mainly from saprophagous species of hoverflies of the tribe Eristalini (Diptera: Syrphidae), whose larvae develop in a wide range of aquatic and semi-aquatic breeding sites that are rich in microbial decay. We present an account of the biology and important details of the life cycle of the pupal parasitoid R. quadrispinus in both natural and controlled conditions. Host suitability, the influence of host pupal age and age of the female parasitoid on her production of progeny was evaluated in laboratory tests. Our results showed that the percentage of pupae of E. tenax that were parasitized by R. quadrispinus decreased as pupae matured, and the optimal age for successful parasitism ranged from 1 to 3 days. This biological information could be useful in the biological control of anthropophilic saprophagous eristalines that can act as potential mechanical vectors of pathogens on farms. [ABSTRACT FROM AUTHOR]

Because of its importance as a pollinator and its potential economic usefulness for the biodegradation of organic animal waste, the genetic and phenotypic diversity of the drone fly, Eristalis tenax L. (Diptera: Syrphidae), was studied in both wild and captive populations from southeastern Europe. Wild specimens from a natural protected habitat (with low human impact), field crop habitat (semisynanthropic condition), and intensive pig farming habitat (synanthropic condition) were compared with a laboratory colony reared on artificial media. An integrative approach was applied based on allozyme loci, cytochrome c oxidase I mitochondrial DNA, wing traits (size and shape), and abdominal color patterns. Our results indicate that the fourth and eighth generations of the laboratory colony show a severe lack of genetic diversity compared with natural populations. Reduced genetic diversity in subsequent generations (F4 and F8) of the laboratory colony was found to be linked with phenotypic divergence. Loss of genetic variability associated with phenotypic differentiation in laboratory samples suggests a founder effect, followed by stochastic genetic processes and inbreeding. Hence, our results have implications for captive bred Eristalis flies, which have been used in crop pollination and biodegradation of organic waste under synanthropic conditions. [ABSTRACT FROM AUTHOR]

ABSTRACT Adult drone flies (Syrphidae: Eristalis spp.) resemble male honeybees in appearance. Their immature stages are commonly known as rat-tailed maggots due to the presence of a very long anal segment and a telescopic breathing tube. The larvae are associated with decaying organic material in liquid or semi-liquid media, as in the case of other saprophagous eristalines. Biological and morphological data were obtained from both laboratory cultures and sampling in the field. Drone flies are important pollinators for wild flowers and crops. In fact, mass rearing protocols of Eristalis species are being developed to be used as efficient alternative pollinators. However, deeper knowledge of larval morphology and biology is required to improve artificial rearing. The production quality control of artificial rearing must manage the consistency and reliability of the production output avoiding, for example contamination with similar species. This article presents the first description of the larva and puparium of E. similis, including a comparative morphological study of preimaginal stages of the anthropophilic and ubiquitous European hoverfly species E. tenax. Scanning electron microscopy has been used for the first time to describe larvae and puparia of both species. Moreover, the preimaginal morphology of E. similis has been compared with all known descriptions of the genus Eristalis. The main diagnostic characters of the preimaginal stages of E. similis are the morphology of the anterior spiracles (shape of clear area and arrangement of facets) and pupal spiracles (length, shape, and arrangement of tubercles). Microsc. Res. Tech. 76:853-861, 2013. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Characterization and differentiation of isomers in biological macromolecules using mass spectrometry is one of the most significant challenges facing scientists in the field. The capability of high-resolution MS instruments along with the development of new fragmentation methods now provides the ability to indirectly differentiate between some isomers. This ability has enabled mass spectrometry to evolve into a multidisciplinary technique incorporating areas such as pharmaceutical research, proteomics, polymer science, medicine, environmental chemistry, and recently archeology. This article aims to review recent developments in mass spectrometry methodologies in the identification of structural and spatial isomers in biological macromolecules, such as aspartic acid and isoaspartic acid (Asp/IsoAsp), leucine and isoleucine (Leu/Ile), glutamic acid and γ-glutamic acid, and D/L enantiomers. © 2012 Wiley Periodicals, Inc. Mass Spec Rev 31:609-625, 2012 [ABSTRACT FROM AUTHOR]

Two polymeric excipients, typically used in enabling drug delivery approaches, are Gelucire 44/14 (a product of Gattefosse s.a, St Priest, France) and polysorbate 80; these are known to improve solubility of poorly water-soluble drugs and, hence, increase their effective bioavailability. In addition to the use of Gelucire 44/14 and polysorbate 80 as excipients in drugs, they are also widely used as cosmetic and food additives. In general, complex structures and compositions of drug excipients impact performance of the formulation in vivo and consequently affect drug absorption. Therefore, a comparison between excipients from different suppliers and batches to batch would provide an indication of the impact on drug product performance and also the study of the effectiveness of the system and any problems associated with the formulation. In this study, high resolution Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) is used to compare two different batches of Gelucire 44/14 and polysorbate 80. With the high resolving power of FTICR MS, it was possible to differentiate between batches of excipients from differences in the identified components. The improved resolution offered by FTICR MS allowed assignment of four polymeric series differences in the two batches of polysorbate 80 and the presence of one compound and three polymeric series differences in the two batches of Gelucire 44/14. The increase in the number of components assigned in the excipients batch using FTICR-MS, compared to the numbers previously assigned by lower resolution TOF MS, underlines the importance of high resolution techniques in analysis of highly complex mixtures. [ABSTRACT FROM AUTHOR]

Collagen is the major component of skin, tendons, ligaments, teeth, and bones, it provides the framework that holds most multicellular animals together, and collagen type I constitutes the major fibrillar collagen of bone. Because of the complexity of collagen's structure, the study of post-translational modifications such as deamidation for this protein is challenging. Although there is no evidence of this protein being used for age assessment, it has been shown that deamidation of collagen is remarkably increased in old bones from mammals. Nonspectrometric methodologies have been used for the determination of the extent of deamidation as a measure of the amount of amide nitrogen released in ammonia as well as constant rates for deamidation of asparagine in collagen. In general, these methodologies required more sample and separation processes. To understand if collagen plays a significant role in the aging process of fossil materials, a simpler and more accurate method is needed to determine the extent of deamidation at the whole protein level. The present work shows a method to determine the extent of deamidation in collagen using Fourier transform ion cyclotron resonance-mass spectrometry (FTICR-MS) along with collisionally activated dissociation (CAD) and electron capture dissociation (ECD). The measured deamidation half-life for three different tryptic peptides from collagen (I) ranged from 2000 to 6000 s under high temperature conditions (∼62 °C) and pH 7.5. [ABSTRACT FROM AUTHOR]

Researchers recognize that ionization state may influence the biological activity of weak acids and bases. Dissociation in aqueous solutions is controlled by the pKa of a compound and the pH of the matrix. Because many pharmaceuticals are implicitly designed as ionizable compounds, site-specific variability in pH of receiving waters may introduce uncertainty to ecological risk assessments. The present study employed 48-h and 7-d toxicity tests with Pimephales promelas exposed to the model weak base pharmaceutical sertraline over a gradient of environmentally relevant surface water pHs. The 48-h experiments were completed in triplicate, and the average lethal concentration values were 647, 205, and 72 μg/L sertraline at pH 6.5, 7.5, and 8.5, respectively. Survivorship, growth, and feeding rate (a nontraditional endpoint linked by other researchers to sertraline's specific mode of action) were monitored during the 7-d experiment. Adverse effects were more pronounced when individuals were exposed to sertraline at pH 8.5 compared to pH 7.5 and 6.5. The pH-dependent toxicological relationships from these studies were related to in-stream pH data for two streams in the Brazos River basin of central Texas, USA. This predictive approach was taken because of the scarcity of environmental analytical data for sertraline. The results of this study emphasized temporal variability associated with in-stream pH linked to seasonal differences within and between these spatially related systems. Relating site-specific pH variability of surface waters to ionization state may allow researchers to reduce uncertainty during ecological risk assessment of pharmaceuticals by improving estimates of biological effects associated with exposure. [ABSTRACT FROM AUTHOR]

Pharmaceuticals and personal care products are being increasingly reported in a variety of biological matrices, including fish tissue; however, screening studies have presently not encompassed broad geographical areas. A national pilot study was initiated in the United States to assess the accumulation of pharmaceuticals and personal care products in fish sampled from five effluent-dominated rivers that receive direct discharge from wastewater treatment facilities in Chicago, Illinois; Dallas, Texas; Orlando, Florida; Phoenix, Arizona; and West Chester, Pennsylvania, USA. Fish were also collected from the Gila River, New Mexico, USA, as a reference condition expected to be minimally impacted by anthropogenic influence. High performance liquid chromatography-tandem mass spectrometry analysis of pharmaceuticals revealed the presence of norfluoxetine, sertraline, diphenhydramine, diltiazem, and carbamazepine at nanogram-per-gram concentrations in fillet composites from effluent-dominated sampling locations; the additional presence of fluoxetine and gemfibrozil was confirmed in liver tissue. Sertraline was detected at concentrations as high as 19 and 545 ng/g in fillet and liver tissue, respectively. Gas chromatography-tandem mass spectrometry analysis of personal care products in fillet composites revealed the presence of galaxolide and tonalide at maximum concentrations of 2,100 and 290 ng/g, respectively, and trace levels of triclosan. In general, more pharmaceuticals were detected at higher concentrations and with greater frequency in liver than in fillet tissues. Higher lipid content in liver tissue could not account for this discrepancy as no significant positive correlations were found between accumulated pharmaceutical concentrations and lipid content for either tissue type from any sampling site. In contrast, accumulation of the personal care products galaxolide and tonalide was significantly related to lipid content. Results suggest that the detection of pharmaceuticals and personal care products was dependent on the degree of wastewater treatment employed. [ABSTRACT FROM AUTHOR]

Community ecology has experienced a major transition, from a focus on patterns in taxonomic composition, to revealing the processes underlying community assembly through the analysis of species functional traits. The power of the functional trait approach is its generality, predictive capacity such as with respect to environmental change, and, through linkage of response and effect traits, the synthesis of community assembly with ecosystem function and services. Lichens are a potentially rich source of information about how traits govern community structure and function, thereby creating opportunity to better integrate lichens into 'mainstream' ecological studies, while lichen ecology and conservation can also benefit from using the trait approach as an investigative tool. This paper brings together a range of author perspectives to review the use of traits in lichenology, particularly with respect to European ecosystems from the Mediterranean to the Arctic-Alpine. It emphasizes the types of traits that lichenologists have used in their studies, both response and effect, the bundling of traits towards the evolution of life-history strategies, and the critical importance of scale (both spatial and temporal) in functional trait ecology. [ABSTRACT FROM AUTHOR]

Assessing the ecological impacts of environmental change on biological communities requires knowledge of the factors driving the spatial patterns of the three diversity facets along extensive environmental gradients. We quantified the taxonomic (TD), functional (FD), and phylogenetic diversity (PD) of lichen epiphytic communities in 23 beech forests along Europe to examine their response to environmental variation (climate, habitat quality, spatial predictors) at a continental geographic scale. We selected six traits related to the climatic conditions in forest ecosystems, the water-use strategy and the nutrient uptake, and we built a phylogenetic tree based on four molecular markers. FD and climate determined TD and PD, with spatial variables also affecting PD. The three diversity facets were primarily shaped by distinct critical predictors, with the temperature diurnal range affecting FD and PD, and precipitation of the wettest month determining TD. Our results emphasize the value of FD for explaining part of TD and PD variation in lichen communities at a broad geographic scale, while highlighting that these diversity facets provide complementary information about the communities' response under changing environmental conditions. Furthermore, traits such as growth form, photobiont type, and reproductive strategy mediated the response of lichen communities to abiotic factors emerging as useful indicators of macroclimatic variations. [ABSTRACT FROM AUTHOR]

Epiphytic richness is continuously declining due to forest fragmentation, logging, burning, agriculture, and livestock. The rate of species loss caused by habitat degradation and loss is more pronounced in Central and South America. Considering the extreme difficulty and time required to identify the more inconspicuous species, rapid diversity assessment methods need to be extrapolated throughout the world. This study correlated lichen growth forms and total epiphytic abundance across 119 forests located in Europe and Central-South America. A total of 54 papers were selected from specific databases focused on lichens. Additionally, data from several unpublished ecological studies were included. Linear regression models showed that epiphytic lichen abundance was highly and positively correlated with the number of growth forms at all geographical levels considered (i.e., Central-South American and European forests, and the combination of both). Thus, the use of growth forms may provide an alternative and complementary way to evaluate epiphytic diversity because most growth forms have cosmopolitan distribution and are easily recognizable. [ABSTRACT FROM AUTHOR]