Research article

Background: An increasing number of studies demonstrate that genetic differentiation and speciation in the sea occur over much smaller spatial scales than previously appreciated given the wide distribution range of many morphologically defined coral reef invertebrate species and the presumed dispersal-enhancing qualities of ocean currents. However, knowledge about the processes that lead to population divergence and speciation is often lacking despite being essential for the understanding, conservation, and management of marine biodiversity. Sponges, a highly diverse, ecologically and economically important reef-invertebrate taxon, exhibit spatial trends in the Indo-West Pacific that are not universally reflected in other marine phyla. So far, however, processes generating those unexpected patterns are not understood.Results: We unraveled the phylogeographic structure of the widespread Indo-Pacific coral reef sponge Leucetta chagosensis across its known geographic range using two nuclear markers: the rDNA internal transcribed spacers (ITS 1&2) and a fragment of the 28S gene, as well as the second intron of the ATP synthetase beta subunit-gene (ATPSb-iII). This enabled the detection of several deeply divergent clades congruent over both loci, one containing specimens from the Indian Ocean (Red Sea and Maldives), another one from the Philippines, and two other large and substructured NW Pacific and SW Pacific clades with an area of overlap in the Great Barrier Reef/Coral Sea...Conclusion: We argue that both founder and vicariance events during the late Pliocene and Pleistocene were responsible to varying degrees for generating the deep phylogeographic structure. This structure was perpetuated largely as a result of the life history of L. chagosensis, resulting in high levels of regional isolation. Reciprocally monophyletic populations constitute putative sibling (cryptic) species, while population para- and polyphyly may indicate incipient speciation processes. The genetic diversity and biodiversity of tropical Indo-Pacific sponges appears to be substantially underestimated since the high level of genetic divergence is not necessarily manifested at the morphological level.researc

Lake Store Finnsjøen – a key for understanding Lateglacial/early Holocene vegetation and ice sheet dynamics in the central Scandes Mountains

The Lateglacial (LG) deglaciation and vegetation development in the Scandes Mountains has been debated for a century. Here we present new evidence from microfossils, radiocarbon dated plant macrofossils and sedimentary ancient DNA from laminated sediments in Lake Store Finnsjøen (1260 m a.s.l.) at Dovre, Central Norway. Combined with previous results from three other Dovre lakes, this allows for new interpretations of events during and immediately after the LG deglaciation. The Finnsjøen sediments present the first uninterrupted record of local vegetation development in the Scandes Mountains from the late Younger Dryas (YD), ca 12,000 cal years BP, to the early Holocene around 9700 cal years BP. The local vegetation in late YD/early Holocene was extremely sparse with pioneer herbs (e.g. Artemisia norvegica, Beckwithia, Campanula cf. uniflora, Koenigia, Oxyria, Papaver, Saxifraga spp.) and dwarf-shrubs (Betula nana, Salix including Salix polaris). From 11,300 cal years BP, local vegetation rapidly closed with dominant Dryas, Saxifraga spp., and Silene acaulis. From ca 10,700 cal years BP, open birch-forests with juniper, Empetrum nigrum and other dwarf-shrubs developed. Pine forests established within the area from 10,300 cal years BP. We identified the cold Preboreal Oscillation (PBO), not earlier described from pollen data in South Norway, around 11,400 cal years BP by a regional pollen signal. Distinct local vegetation changes were not detected until the post-PBO warming around 11,300 cal years BP. Apparently, the earlier warming at the YD/Holocene transition at 11,650 cal years BP was too weak and short-lived for vegetation closure at high altitudes at Dovre. For the first time, we demonstrate a regional glacier readvance and local ice cap formations during the YD in the Scandes Mountains. In two of the deep lakes with small catchments, YD glaciation blocked sedimentation without removing old sediments and caused a hiatus separating sediments of the ice-free LG interstadial (LGI) from those of the ice-free Holocene period. Both regional glaciers and local ice caps caused hiati. Ice-free pre-YD conditions at Dovre followed by a YD readvance point to a scenario that is intermediate between the maximum ice model postulating a thick glacier during the entire LG, and the minimum ice model postulating thin and multi-domed early LG ice

Deep genetic divergences among Indo-Pacific populations of the coral reef sponge Leucetta chagosensis (Leucettidae): Founder effects, vicariance, or both?

<p>Abstract</p> <p>Background</p> <p>An increasing number of studies demonstrate that genetic differentiation and speciation in the sea occur over much smaller spatial scales than previously appreciated given the wide distribution range of many morphologically defined coral reef invertebrate species and the presumed dispersal-enhancing qualities of ocean currents. However, knowledge about the processes that lead to population divergence and speciation is often lacking despite being essential for the understanding, conservation, and management of marine biodiversity. Sponges, a highly diverse, ecologically and economically important reef-invertebrate taxon, exhibit spatial trends in the Indo-West Pacific that are not universally reflected in other marine phyla. So far, however, processes generating those unexpected patterns are not understood.</p> <p>Results</p> <p>We unraveled the phylogeographic structure of the widespread Indo-Pacific coral reef sponge <it>Leucetta chagosensis </it>across its known geographic range using two nuclear markers: the rDNA internal transcribed spacers (ITS 1&2) and a fragment of the 28S gene, as well as the second intron of the <it>ATP synthetase beta subunit</it>-gene (<it>ATPSb</it>-iII). This enabled the detection of several deeply divergent clades congruent over both loci, one containing specimens from the Indian Ocean (Red Sea and Maldives), another one from the Philippines, and two other large and substructured NW Pacific and SW Pacific clades with an area of overlap in the Great Barrier Reef/Coral Sea. Reciprocally monophyletic populations were observed from the Philippines, Red Sea, Maldives, Japan, Samoa, and Polynesia, demonstrating long-standing isolation. Populations along the South Equatorial Current in the south-western Pacific showed isolation-by-distance effects. Overall, the results pointed towards stepping-stone dispersal with some putative long-distance exchange, consistent with expectations from low dispersal capabilities.</p> <p>Conclusion</p> <p>We argue that both founder and vicariance events during the late Pliocene and Pleistocene were responsible to varying degrees for generating the deep phylogeographic structure. This structure was perpetuated largely as a result of the life history of <it>L. chagosensis</it>, resulting in high levels of regional isolation. Reciprocally monophyletic populations constitute putative sibling (cryptic) species, while population para- and polyphyly may indicate incipient speciation processes. The genetic diversity and biodiversity of tropical Indo-Pacific sponges appears to be substantially underestimated since the high level of genetic divergence is not necessarily manifested at the morphological level.</p

Assessing arctic flora composition in the Siberian treeline ecotone by vegetation mapping, pollen analyses and sedimentary DNA metabarcoding

Arctic environments are one of the most climatically influenced areas worldwide. These influences are currently causing major changes in vegetation composition, for example in the Taymyr lowlands, which harbour the northernmost boreal-arctic treeline areas of the world. The most dominant species of the treeline ecotone in this region are Larix gmelinii, Betula nana and Alnus viridis. They are presently shifting in density and range, and have done so multiple times throughout the Holocene. To understand the vegetation changes it is necessary to investigate the current state, before deducing changes for other time phases of the Holocene. To this end a field campaign was carried out at the Taymyr lowlands in 2013 to perform a multidisciplinary investigation by combining methods from vegetation mapping, palynological records and sedimentary DNA metabarcoding. We sampled lake sediments and mapped the vegetation along a transect spanning the treeline ecotone, with changing vegetation composition and density. Our results of the surveyed vegetation will help to investigate the current state of vegetation and will also be used as calibration of the pollen and DNA metabarcoding records. The comparison of the vegetation and pollen record will allow the assessment of over- or underrepresentation of certain taxa within the pollen signal, and this will enable a more secure interpretation of historic pollen records. We will also test this for the DNA metabarcoding data, which has not yet been systematically done for lake sediments in arctic latitudes. This multidisciplinary investigation will draw a more comprehensive image of the current vegetation composition at the Taymyr lowlands than has been possible to date, and will enable a more secure interpretation of historical vegetation change in this highly dynamic area

Modern and ancient DNA in lacustrine sediments – Vegetation signals unraveled

Current climatic changes, mostly triggered by global warming, influence broad parts of the northern latitudes all over the world, and reliable assessments of present and past vegetation are highly relevant to predict the future development of Arctic ecosystems. The northernmost Siberian arcto-boreal treeline areas in the Taymyr lowlands may be particularly affected by climatic changes, with latitudinal shifts of the treeline ecotone and resulting vegetation changes from tundra to taiga. Obtaining reliable information about present vegetation composition in such remote arctic locations is difficult, as vegetation surveys in the field can typically only be carried out during brief visits, and the flowering season is short. Although these techniques are time consuming, methods like vegetation assessment by ground surveys or palynological analyses are common tools to evaluate floral composition and provide valuable, complimentary information. While vegetation surveys mainly provide information about the status quo, pollen analyses also allow investigation of vegetation back in time. In recent years, sedimentary DNA has emerged as an additional and effective tool to improve knowledge about past vegetation. DNA metabarcoding of lake sediments and sediment cores has become more and more relevant as a tool for such research, but an explicit assessment of lake sediment DNA data in comparison to data obtained from pollen and vegetation surveys is still lacking. Here, we present a study comparing these three vegetation assessment methods for 31 lakes within a 300 km transect in arctic Siberia, reaching from Tundra, through the treeline area, to the light Taiga. Surface sediments of lakes were taken, subsampled for DNA and pollen analyses and processed in the respective laboratories. Together with six representative vegetation surveys, we present results of this comparative study. Our results show that taxa assigned by DNA sequence analyses are comparable to those found in the pollen and vegetation analyses. Overall, the DNA provides a higher taxonomical level of identification, while the pollen grains mainly identify to genus level. Compared to the vegetation survey, pollen and DNA provide more information, as they are able to track vegetation elements, which could not been surveyed at the time of the year the surveys were carried out. The results show that the combination and comparison of pollen, DNA and vegetation seems to serve as a calibration set for future investigations of such remote and highly dynamic ecosystems. Our investigation draws a multidisciplinary, comprehensive image of the current composition of the Siberian lowland vegetation by combining well established and promising, newly emerging methods

Notes on the ecology and distribution of a water flea complex (Anomopoda, Daphniidae) revealed by new DNA barcodes in the Iberian Peninsula

Available DNA barcodes of freshwater zooplankton are scarce in regions like the Iberian Peninsula, which harbours many rare and endemic species and is considered a hotspot of crustacean biodiversity. Recently, a new species of Ceriodaphnia (Cladocera: Daphniidae) was described using morphological analysis of specimens in the Mediterranean region and molecular data on a single locality in southern Spain. In our study, we detected the presence of the newly discovered taxa and here, we provide new DNA sequences on the barcoding region mitochondrial cytochrome c oxidase I together with ecological information of the recently described Ceriodaphnia smirnovi. Additionally, we built a molecular phylogenetic tree and genetically compared these specimens with previously available mitochondrial DNA sequences and with new sequences of the genus recovered in Iberia. Our data suggest that this morphospecies might contain some cryptic taxa and might be more common than previously thought, occupying temporary to semi-permanent ecosystems, with vegetation and highly variable pH and turbidity conditions. Moreover, the existence of a non-identified clade within our phylogenetic tree requires additional morphological research. Our study highlights the need for further research on microcrustacean biota to better constrain its spatial boundaries, phylogenetic relationship and determine species hiding cryptic diversityDepartamento de Estratigrafía y Paleontologí

Reductions in microfilaridermia by repeated ivermectin treatment are associated with lower Plasmodium-specific Th17 immune responses in Onchocerca volvulus-infected individuals

Background: 37 million individuals are currently infected with Onchocerca volvulus (O. volvulus), a parasitic nematode that elicits various dermal manifestations and eye damage in man. Disease control is primarily based on distributing ivermectin in mass drug administration (MDA) programmes which aim at breaking transmission by eliminating microfilariae (MF), the worm's offspring. The majority of infected individuals present generalized onchocerciasis, which is characterized by hyporesponsive immune responses and high parasite burden including MF. Recently, in areas that have been part of MDA programmes, individuals have been identified that present nodules but are amicrofilaridermic (a-MF) and our previous study showed that this group has a distinct immune profile. Expanding on those findings we determined the immune responses of O. volvulus-infected individuals to a Plasmodium-derived antigen MSP-1 (merozoite surface protein-1), which is required by the parasite to enter erythrocytes. Methods: Isolated PBMCs from O. volvulus-infected individuals (164 MF+ and 46 a-MF) and non-infected volunteers from the same region (NEN), were stimulated with MSP-1 and the resulting supernatant screened for the presence of IL-5, IL-13, IFN-γ, TNF-α, IL-6, IL-17A and IL-10. These findings were then further analyzed following regression analysis using the covariates MF, ivermectin (IVM) and region. The latter referred to the Central or Ashanti regions of Ghana, which, at the time sampling, had received 8 or 1 round of MDA respectively. Results: IL-5, IL-13 and IFN-γ responses to MSP-1 were not altered between NEN and O. volvulus-infected individuals nor were any associations revealed in the regression analysis. IL-10, IL-6 and TNF-α MSP-1 responses were, however, significantly elevated in cultures from infected individuals. Interestingly, when compared to a-MF individuals, MSP-induced IL-17A responses were significantly higher in MF+ patients. Following multivariable regression analysis these IL-10, IL-6, TNF-α and IL-17A responses were all dominantly associated with the regional covariate. Conclusions: Consequently, areas with a lowered infection pressure due to IVM MDA appear to influence bystander responses to Plasmodium-derived antigens in community members even if they have not regularly participated in the therapy

Holocene vegetation change and turnovers of treeline forming species

The prospected strong high-latitude warming is projected to cause a northward move of the arctic-boreal treeline. These changes will potentially have significant effects on climate, but their timing and mode are not well understood. Besides being governed directly by temperature increases, speed of treeline changes will also be influenced by the capacity of migration and establishment, and by competition between different treeline forming species. In Siberia, where about half of the global circum-arctic boreal treeline is located, the treeline is formed by monospecific stands of three species of larch, Larix sibirica, Larix gmelinii and Larix cajanderi. There is clear evidence for ecological separation, particularly between L. sibirica and the northeastern species, with only L. gmelinii and L. cajanderi being able to survive on permafrost with an active layer depth of less than 1-2 m, but L. sibirica being competitively superior at sites with low permafrost tables. Under a warming climate, the respective ranges of the treeline forming species are projected to shift to the Northeast, causing turnovers of forest tree species. The Siberian treeline has undergone several pronounced latitudinal fluctuations in the Holocene, and detailed analyses of the historical processes of vegetation change and competitive displacement would add to predictions for the projected future shift. We are using sedimentary ancient DNA to analyze lake sediment cores spanning most of the Holocene from the southern Taymyr peninsula, where the ranges of L. sibirica and L. gmelinii come together. Changes of the complete vegetation are revealed by DNA metabarcoding and pollen analyses, while diagnostic mitochondrial haplotypes trace the temporal dynamics in distribution of the two closely related larch species. We incorporated these two species into our larch population dynamics model LAVESI to understand the influence competition between these species might have on the speed and timing of treeline movement under changing climates. Simulations were forced with regional climate series at locations in the vicinity of the sampled lakes. These analyses offer a very high degree of resolution and shed light on the complicated ecological processes leading to a change in overall vegetation

Siberian treeline dynamics in a warming climate - results from larch population genetics and vegetation modelling

A vegetation change from open tundra to dense taiga will fuel the global warming by positive feedback caused by albedo decreases. Yet, it is unclear how fast the arctic treeline, formed of Larix species, will advance north in the next decades. The most determinant factor of tree migration is the ability to disperse seeds (and pollen). Hence, to realistically forecast the migration of tree species in a dynamic vegetation model, it is crucial to incorporate reliable estimates of dispersal. Classical methods, for example counting seeds in seed traps, have been used to describe local dispersal abilities but are not applicable to give precise estimates on rare long-distance dispersal events. In this study we overcome this with the help of modern molecular techniques. By using a set of 16 nuclear microsatellites we inferred the cryptic signal of heritage among larch individuals to study the migration history among well-established tree stands and for different time-cohorts. We analyzed the genetic structure of larch populations for several latitudinal transects spanning north-to-south from tundra to open taiga forests in Siberia and additionally of several age cohorts which established throughout the last century in prevailing cold and warm periods. Finally, we present the results of simulations with our individual-based model LAVESI which was developed by us originally to study population dynamics of larch forest stands. Using downscaled global climate models and 'representative carbon pathway' (RCP) scenarios it is feasible to project the future treeline in Siberia

Emotional burnout of specialists in socio-occupational professions: contemporary views on the problem

Представлено сучасні підходи до проблеми вигорання у представників соціономічних професій у контексті емоційної праці, емоційного і когнітивного дисонансу. Проаналізовано й узагальнено наукову літературу з питань вигорання, визначено три основні його компоненти: емоційне і/або фізичне виснаження, зниження продуктивності праці і надмірна деперсоналізація. На основі аналізу визначень вигорання встановлено його зв’язок з емоційною працею (регуляцією і вираженням емоційних станів). Обстоюється думка, що фахівці соціономічних професій особливо вразливі до вигорання, оскільки тривалий час перебувають у стані, коли необхідно постійно контролювати свої емоції, брати на себе відповідальність і відчувати невизначеність, працюючи з іншими людьми. Емоційну працю розглянуто як предиктор вигорання у фахівців соціономічних професій. На основі аналізу літератури, присвяченої проблемам вигорання та емоційного дисонансу, висловлено припущення, що вимоги щодо емоційної праці зумовлюють різноманітність проявів синдрому виго-рання (у тому числі виснаження, цинізму, зниження продуктивності праці та погіршення самопочуття), а знання симптомів вигорання дало б змогу фахівцям соціономічних професій запобігти виникненню та загостренню цього стану.This article deals with the modern approaches to the problem of burnout of helping professionals in the context of emotional labor, emotional and cognitive dissonance. The burnout literature is reviewed, compared, and summarized. The definition of burnout is proposed including three components: emotional and/or physical exhaustion, lowered work productivity, and excessive depersonalization. Based on an analysis of the definitions of burnout, the paper focuses on the connec-tion of burnout and emotional work (regulation of feelings and emotional expression). It is also maintained a fact that helping professionals are especially vulnerable to burnout because of the necessity to control own emotions for a long time, to take responsibilities, and to feel uncertainties they encounter while working with others. The current study discussed emotional labor as a predictor of burnout of helping professionals. On the basis of the literature on burnout and emotional dissonance, the author of this article hypothesized that emotional job demands would explain variances of burnout (i.e., exhaustion and cynicism). Knowledge of abovementioned syndromes would help socionomy professionals to avoid emergence and aggravation of emotional burnout.Представлены современные подходы к проблеме выгорания у представителей социономических профессий в контексте эмоциональной труда, эмоционального и когнитивного диссонанса. Проанализированы и обобщены научную литературу по вопросам выгорания, определены три основные его компоненты: эмоциональное и / или физическое истощение, снижение производительности труда и чрезмерная деперсонализация. На основе анализа определений выгорания установлена ​​его связь с эмоциональной трудом (регуляцией и выражением эмоциональных состояний). Отстаивается мнение, что специалисты социономических профессий особенно уязвимы к выгоранию, поскольку длительное время находятся в состоянии, когда необходимо постоянно контролировать свои эмоции, брать на себя ответственность и чувствовать неопределенность, работая с другими людьми. Эмоциональный труд рассмотрен как предиктор выгорания у специалистов социономических профессий. На основе анализа литературы, посвященной проблемам выгорания и эмоционального диссонанса, высказано предположение, что требования по эмоциональной труда обусловливают разнообразие проявлений синдрома выгорания (в том числе истощения, цинизма, снижение производительности труда и ухудшение самочувствия), а знание симптомов выгорания позволило бы специалистам социономических профессий предотвратить возникновение и обострение этого состояния