451 research outputs found

    Environmental factors influence both abundance and genetic diversity in a widespread bird species.

    Get PDF
    Genetic diversity is one of the key evolutionary variables that correlate with population size, being of critical importance for population viability and the persistence of species. Genetic diversity can also have important ecological consequences within populations, and in turn, ecological factors may drive patterns of genetic diversity. However, the relationship between the genetic diversity of a population and how this interacts with ecological processes has so far only been investigated in a few studies. Here, we investigate the link between ecological factors, local population size, and allelic diversity, using a field study of a common bird species, the house sparrow (Passer domesticus). We studied sparrows outside the breeding season in a confined small valley dominated by dispersed farms and small-scale agriculture in southern France. Population surveys at 36 locations revealed that sparrows were more abundant in locations with high food availability. We then captured and genotyped 891 house sparrows at 10 microsatellite loci from a subset of these locations (N = 12). Population genetic analyses revealed weak genetic structure, where each locality represented a distinct substructure within the study area. We found that food availability was the main factor among others tested to influence the genetic structure between locations. These results suggest that ecological factors can have strong impacts on both population size per se and intrapopulation genetic variation even at a small scale. On a more general level, our data indicate that a patchy environment and low dispersal rate can result in fine-scale patterns of genetic diversity. Given the importance of genetic diversity for population viability, combining ecological and genetic data can help to identify factors limiting population size and determine the conservation potential of populations

    Two Trebouxia algae with different physiological performances are ever-present in lichen thalli of Ramalina farinacea. Coexistence versus Competition

    Full text link
    Ramalina farinacea is an epiphytic fruticose lichen that is relatively abundant in areas with Mediterranean, subtropical or temperate climates. Little is known about photobiont diversity in different lichen populations. The present study examines the phycobiont composition of several geographically distant populations of R. farinacea from the Iberian Peninsula, Canary Islands and California as well as the physiological performance of isolated phycobionts. Based on anatomical observations and molecular analyses, the coexistence of two different taxa of Trebouxia (working names, TR1 and TR9) was determined within each thallus of R. farinacea in all of the analysed populations. Examination of the effects of temperature and light on growth and photosynthesis indicated a superior performance of TR9 under relatively high temperatures and irradiances while TR1 thrived at moderate temperature and irradiance. Ramalina farinacea thalli apparently represent a specific and selective form of symbiotic association involving the same two Trebouxia phycobionts. Strict preservation of this pattern of algal coexistence is likely favoured by the different and probably complementary ecophysiological responses of each phycobiont, thus facilitating the proliferation of this lichen in a wide range of habitats and geographic areas. © 2010 Society for Applied Microbiology and Blackwell Publishing Ltd.This study was funded by the Spanish Ministry of Education and Science (CGL2006-12917-C02-01/02), the Spanish Ministry of Science and Innovation (CGL2009-13429-C02-01/02), the AECID (PCI_A/024755/09) and the Generalitat Valenciana (PROMETEO 174/2008 GVA). We are grateful to Dr J. Gimeno-Romeu (University of California, Davis, USA) and to Dr P. J. G. de Nova (IREC, Ciudad Real, Spain), who were the first to isolate DNA from Ramalina farinacea thalli in our group. Wendy Ran revised the manuscript in English.Casano, L.; Del Campo, E.; GarcĂ­a Breijo, FJ.; Reig Armiñana, J.; Gasulla, F.; Del Hoyo, A.; GuĂ©ra, A.... (2011). Two Trebouxia algae with different physiological performances are ever-present in lichen thalli of Ramalina farinacea. Coexistence versus Competition. Environmental Microbiology. 13(3):806-818. https://doi.org/10.1111/j.1462-2920.2010.02386.xS806818133Angert, A. L., Huxman, T. E., Chesson, P., & Venable, D. L. (2009). Functional tradeoffs determine species coexistence via the storage effect. Proceedings of the National Academy of Sciences, 106(28), 11641-11645. doi:10.1073/pnas.0904512106Baker, N. R., & Oxborough, K. (s. f.). Chlorophyll Fluorescence as a Probe of Photosynthetic Productivity. Advances in Photosynthesis and Respiration, 65-82. doi:10.1007/978-1-4020-3218-9_3Barreno , E. Herrera-Campos , M. GarcĂ­a-Breijo , F. Gasulla , F. Reig-Armiñana , J. 2008 Non photosynthetic bacteria associated to cortical structures on Ramalina and Usnea thalli from Mexico http://192.104.39.110/archive/IAL6abstracts.pdfBECK, A., FRIEDL, T., & RAMBOLD, G. (1998). Selectivity of photobiont choice in a defined lichen community: inferences from cultural and molecular studies. New Phytologist, 139(4), 709-720. doi:10.1046/j.1469-8137.1998.00231.xBilger, W., & Bjïżœrkman, O. (1991). Temperature dependence of violaxanthin de-epoxidation and non-photochemical fluorescence quenching in intact leaves ofGossypium hirsutum L. andMalva parviflora L. Planta, 184(2), 226-234. doi:10.1007/bf01102422Bjïżœrkman, O., & Demmig, B. (1987). Photon yield of O2 evolution and chlorophyll fluorescence characteristics at 77 K among vascular plants of diverse origins. Planta, 170(4), 489-504. doi:10.1007/bf00402983Bold, H. C., & Parker, B. C. (1962). Some supplementary attributes in the classification of chlorococcum species. Archiv fïżœr Mikrobiologie, 42(3), 267-288. doi:10.1007/bf00422045Cenis, J. L. (1992). Rapid extraction of fungal DNA for PCR amplification. Nucleic Acids Research, 20(9), 2380-2380. doi:10.1093/nar/20.9.2380Del Campo, E. M., Casano, L. M., Gasulla, F., & Barreno, E. (2010). Suitability of chloroplast LSU rDNA and its diverse group I introns for species recognition and phylogenetic analyses of lichen-forming Trebouxia algae. Molecular Phylogenetics and Evolution, 54(2), 437-444. doi:10.1016/j.ympev.2009.10.024Demmig-Adams, B., & Adams, W. W. (1996). The role of xanthophyll cycle carotenoids in the protection of photosynthesis. Trends in Plant Science, 1(1), 21-26. doi:10.1016/s1360-1385(96)80019-7Demmig-Adams, B., Mïżœguas, C., Adams, W. W., Meyer, A., Kilian, E., & Lange, O. L. (1990). Effect of high light on the efficiency of photochemical energy conversion in a variety of lichen species with green and blue-green phycobionts. Planta, 180(3), 400-409. doi:10.1007/bf01160396DePriest, P. T. (2004). Early Molecular Investigations of Lichen-Forming Symbionts: 1986–2001. Annual Review of Microbiology, 58(1), 273-301. doi:10.1146/annurev.micro.58.030603.123730DOERING, M., & PIERCEY-NORMORE, M. D. (2009). Genetically divergent algae shape an epiphytic lichen community on Jack Pine in Manitoba. The Lichenologist, 41(1), 69-80. doi:10.1017/s0024282909008111Friedl, T. (1989). Comparative ultrastructure of pyrenoids inTrebouxia (Microthamniales, Chlorophyta). Plant Systematics and Evolution, 164(1-4), 145-159. doi:10.1007/bf00940435Gasulla, F., de Nova, P. G., Esteban-Carrasco, A., Zapata, J. M., Barreno, E., & GuĂ©ra, A. (2009). Dehydration rate and time of desiccation affect recovery of the lichenic algae Trebouxia erici: alternative and classical protective mechanisms. Planta, 231(1), 195-208. doi:10.1007/s00425-009-1019-yGasulla, F., GuĂ©ra, A., & Barreno, E. (2010). “A simple and rapid method for isolating lichen photobionts“. Symbiosis, 51(2), 175-179. doi:10.1007/s13199-010-0064-4Gauze, G. F. (1934). The struggle for existence, by G. F. Gause. doi:10.5962/bhl.title.4489Genty, B., Briantais, J.-M., & Baker, N. R. (1989). The relationship between the quantum yield of photosynthetic electron transport and quenching of chlorophyll fluorescence. Biochimica et Biophysica Acta (BBA) - General Subjects, 990(1), 87-92. doi:10.1016/s0304-4165(89)80016-9Gross, K. (2008). Positive interactions among competitors can produce species-rich communities. Ecology Letters, 11(9), 929-936. doi:10.1111/j.1461-0248.2008.01204.xGUZOW-KRZEMIƃSKA, B. (2006). Photobiont flexibility in the lichen Protoparmeliopsis muralis as revealed by ITS rDNA analyses. The Lichenologist, 38(5), 469-476. doi:10.1017/s0024282906005068Haruta, S., Kato, S., Yamamoto, K., & Igarashi, Y. (2009). Intertwined interspecies relationships: approaches to untangle the microbial network. Environmental Microbiology, 11(12), 2963-2969. doi:10.1111/j.1462-2920.2009.01956.xJOHANSEN, S., & HAUGEN, P. (2001). A new nomenclature of group I introns in ribosomal DNA. RNA, 7(7), 935-936. doi:10.1017/s1355838201010500Jones, A. ., Berkelmans, R., van Oppen, M. J. ., Mieog, J. ., & Sinclair, W. (2008). A community change in the algal endosymbionts of a scleractinian coral following a natural bleaching event: field evidence of acclimatization. Proceedings of the Royal Society B: Biological Sciences, 275(1641), 1359-1365. doi:10.1098/rspb.2008.0069Kopecky, J., Azarkovich, M., PfĂŒndel, E. E., Shuvalov, V. A., & Heber, U. (2005). Thermal Dissipation of Light Energy is Regulated Differently and by Different Mechanisms in Lichens and Higher Plants. Plant Biology, 7(2), 156-167. doi:10.1055/s-2005-837471Kosugi, M., Arita, M., Shizuma, R., Moriyama, Y., Kashino, Y., Koike, H., & Satoh, K. (2009). Responses to Desiccation Stress in Lichens are Different from Those in Their Photobionts. Plant and Cell Physiology, 50(4), 879-888. doi:10.1093/pcp/pcp043Kranner, I., Cram, W. J., Zorn, M., Wornik, S., Yoshimura, I., Stabentheiner, E., & Pfeifhofer, H. W. (2005). Antioxidants and photoprotection in a lichen as compared with its isolated symbiotic partners. Proceedings of the National Academy of Sciences, 102(8), 3141-3146. doi:10.1073/pnas.0407716102Kroken, S., & Taylor, J. W. (2000). Phylogenetic Species, Reproductive Mode, and Specificity of the Green AlgaTrebouxiaForming Lichens with the Fungal GenusLetharia. The Bryologist, 103(4), 645-660. doi:10.1639/0007-2745(2000)103[0645:psrmas]2.0.co;2Little, A. F. (2004). Flexibility in Algal Endosymbioses Shapes Growth in Reef Corals. Science, 304(5676), 1492-1494. doi:10.1126/science.1095733Loarie, S. R., Duffy, P. B., Hamilton, H., Asner, G. P., Field, C. B., & Ackerly, D. D. (2009). The velocity of climate change. Nature, 462(7276), 1052-1055. doi:10.1038/nature08649Muggia, L., Grube, M., & Tretiach, M. (2008). Genetic diversity and photobiont associations in selected taxa of the Tephromela atra group (Lecanorales, lichenised Ascomycota). Mycological Progress, 7(3), 147-160. doi:10.1007/s11557-008-0560-6Niyogi, K. K. (2004). Is PsbS the site of non-photochemical quenching in photosynthesis? Journal of Experimental Botany, 56(411), 375-382. doi:10.1093/jxb/eri056O’Brien, H. E., Miadlikowska, J., & Lutzoni, F. (2005). Assessing host specialization in symbiotic cyanobacteria associated with four closely related species of the lichen fungusPeltigera. European Journal of Phycology, 40(4), 363-378. doi:10.1080/09670260500342647Ohmura, Y., Kawachi, M., Kasai, F., Watanabe, M. M., & Takeshita, S. (2006). Genetic combinations of symbionts in a vegetatively reproducing lichen,Parmotrema tinctorum, based on ITS rDNA sequences. The Bryologist, 109(1), 43-59. doi:10.1639/0007-2745(2006)109[0043:gcosia]2.0.co;2Piercey-Normore, M. D. (2005). The lichen-forming ascomyceteEvernia mesomorphaassociates with multiple genotypes ofTrebouxia jamesii. New Phytologist, 169(2), 331-344. doi:10.1111/j.1469-8137.2005.01576.xPombert, J.-F., Lemieux, C., & Turmel, M. (2006). BMC Biology, 4(1), 3. doi:10.1186/1741-7007-4-3Rambold, G., Friedl, T., & Beck, A. (1998). Photobionts in Lichens: Possible Indicators of Phylogenetic Relationships? The Bryologist, 101(3), 392. doi:10.1639/0007-2745(1998)101[392:pilpio]2.0.co;2Romeike, J., Friedl, T., Helms, G., & Ott, S. (2002). Genetic Diversity of Algal and Fungal Partners in Four Species of Umbilicaria (Lichenized Ascomycetes) Along a Transect of the Antarctic Peninsula. Molecular Biology and Evolution, 19(8), 1209-1217. doi:10.1093/oxfordjournals.molbev.a004181Rosenberg, E., Sharon, G., & Zilber-Rosenberg, I. (2009). The hologenome theory of evolution contains Lamarckian aspects within a Darwinian framework. Environmental Microbiology, 11(12), 2959-2962. doi:10.1111/j.1462-2920.2009.01995.xSchreiber, U., Schliwa, U., & Bilger, W. (1986). Continuous recording of photochemical and non-photochemical chlorophyll fluorescence quenching with a new type of modulation fluorometer. Photosynthesis Research, 10(1-2), 51-62. doi:10.1007/bf00024185Skaloud, P., & Peksa, O. (2010). Evolutionary inferences based on ITS rDNA and actin sequences reveal extensive diversity of the common lichen alga Asterochloris (Trebouxiophyceae, Chlorophyta). Molecular Phylogenetics and Evolution, 54(1), 36-46. doi:10.1016/j.ympev.2009.09.035Wegley, L., Edwards, R., Rodriguez-Brito, B., Liu, H., & Rohwer, F. (2007). Metagenomic analysis of the microbial community associated with the coral Porites astreoides. Environmental Microbiology, 9(11), 2707-2719. doi:10.1111/j.1462-2920.2007.01383.xWeis, E., & Berry, J. A. (1987). Quantum efficiency of Photosystem II in relation to ‘energy’-dependent quenching of chlorophyll fluorescence. Biochimica et Biophysica Acta (BBA) - Bioenergetics, 894(2), 198-208. doi:10.1016/0005-2728(87)90190-3Wornik, S., & Grube, M. (2009). Joint Dispersal Does Not Imply Maintenance of Partnerships in Lichen Symbioses. Microbial Ecology, 59(1), 150-157. doi:10.1007/s00248-009-9584-yYAHR, R., VILGALYS, R., & DEPRIEST, P. T. (2004). Strong fungal specificity and selectivity for algal symbionts in Florida scrub Cladonia lichens. Molecular Ecology, 13(11), 3367-3378. doi:10.1111/j.1365-294x.2004.02350.xYahr, R., Vilgalys, R., & DePriest, P. T. (2006). Geographic variation in algal partners of Cladonia subtenuis (Cladoniaceae) highlights the dynamic nature of a lichen symbiosis. New Phytologist, 171(4), 847-860. doi:10.1111/j.1469-8137.2006.01792.xZoller, S. (2003). Slow algae, fast fungi: exceptionally high nucleotide substitution rate differences between lichenized fungi Omphalina and their symbiotic green algae Coccomyxa. Molecular Phylogenetics and Evolution, 29(3), 629-640. doi:10.1016/s1055-7903(03)00215-

    Rapid assessment of nonlinear optical propagation effects in dielectrics

    Get PDF
    8 pĂĄgs.; 6 figs.; Open Access funded by Creative Commons Atribution Licence 4.0Ultrafast laser processing applications need fast approaches to assess the nonlinear propagation of the laser beam in order to predict the optimal range of processing parameters in a wide variety of cases. We develop here a method based on the simple monitoring of the nonlinear beam shaping against numerical prediction. The numerical code solves the nonlinear Schrodinger equation with nonlinear absorption under simplified conditions by employing a state-of-the art computationally efficient approach. By comparing with experimental results we can rapidly estimate the nonlinear refractive index and nonlinear absorption coefficients of the material. The validity of this approach has been tested in a variety of experiments where nonlinearities play a key role, like spatial soliton shaping or fs-laser waveguide writing. The approach provides excellent results for propagated power densities for which free carrier generation effects can be neglected. Above such a threshold, the peculiarities of the nonlinear propagation of elliptical beams enable acquiring an instantaneous picture of the deposition of energy inside the material realistic enough to estimate the effective nonlinear refractive index and nonlinear absorption coefficients that can be used for predicting the spatial distribution of energy deposition inside the material and controlling the beam in the writing process.This work has been partly funded by MINECO TEC2011-22422 project. J. de H. acknowledges funding from the JAE CSIC Program (pre-doctoral fellowship co-funded by the European Social Fund). A.P. acknowledges support from the People Program (Marie Curie Actions) Incoming International Fellowship (CHRONOS) under REA grant agreement nu [327627].Peer Reviewe

    Solar active envelope module with an adjustable transmittance/absorptance

    Get PDF
    A solar active envelope module with a high flexibility degree is proposed in this paper. The transparent module controls the day-lighting of the room, improving the indoor environment, while absorbing the superfluous solar energy inside. That energy is used to increase the efficiency of heating, ventilation, and the air-conditioning (HVAC) system of the building. This is carried out through a fine control of the absorptance of the envelope module. The active envelope module consists of three glazed chambers with advanced coatings and frames to assure a minimum thermal transmittance while allowing transparency. A fluid containing heat-absorbing nanoparticles flows inside the central chamber and is heated up due to the impinging solar energy. Unlike other systems proposed in the past, which included transparency control systems based on complex filters and chemical processes, the absorption of the module is controlled by the variation of the thickness of the central chamber with a mechanical device. That is, varying the thickness of the central chamber, it allows controlling the absorptance of the whole system and, as a result, indoor day-lighting and thermal loads. Therefore, a new system is proposed that enables to

    Matrix type and landscape attributes modulate avian taxonomic and functional spillover across habitat boundaries in the Brazilian Atlantic Forest

    Get PDF
    Land use intensification drives biodiversity loss worldwide. In heterogeneous landscape mosaics, both overall forest area and anthropogenic matrix structure induce changes in biological communities in primary habitat remnants. However, community changes via cross‐habitat spillover processes along forest‐matrix interfaces remain poorly understood. Moreover, information on how landscape attributes affect spillover processes across habitat boundaries are embryonic. Here, we quantify avian α and ÎČ‐diversity (as proxies of spillover rates) across two dominant types of forest‐matrix interfaces (forest‐pasture and forest‐eucalyptus plantation) within the Atlantic Forest biodiversity hotspot in southeast Brazil. We also assess the effects of anthropogenic matrix type and landscape attributes (forest cover, edge density and land‐use diversity) on bird taxonomic and functional ÎČ‐diversity across forest‐matrix boundaries. Alpha taxonomic richness was higher in forest edges than within both matrix types, but between matrix types, it was higher in pastures than in eucalyptus plantations. Although significantly higher in forests edges than in the adjacent eucalyptus, bird functional richness did not differ between forest edges and adjacent pastures. Community changes (ÎČ‐diversity) related to species and functional replacements (turnover component) were higher across forest‐pasture boundaries, whereas changes related to species and functional loss (nested component) were higher across forest‐eucalyptus boundaries. Forest edges adjacent to eucalyptus had significant higher species and functional replacements than forest edges adjacent to pastures. Forest cover negatively influenced functional ÎČ‐diversity across both forest‐pasture and forest‐eucalyptus interfaces. We show the importance of matrix type and the structure of surrounding landscapes (mainly forest cover) on rates of bird assemblage spillover across forest‐matrix boundaries, which has profound implications to biological fluxes, ecosystem functioning and land‐use management in human‐modified landscapes

    Lichen rehydration in heavy metal polluted environments: Pb modulates the oxidative response of both Ramalina farinacea thalli and its isolated microalgae

    Get PDF
    Lichens are adapted to desiccation/rehydration and accumulate heavy metals, which induce ROS especially from the photobiont photosynthetic pigments. Although their mechanisms of abiotic stress tolerance are still to be unravelled, they seem related to symbionts' reciprocal upregulation of antioxidant systems. With the aim to study the effect of Pb on oxidative status during rehydration, the kinetics of intracellular ROS, lipid peroxidation and chlorophyll autofluorescence of whole Ramalina farinacea thalli and its isolated microalgae (Trebouxia TR1 and T. TR9) was recorded. A genetic characterization of the microalgae present in the thalli used was also carried out in order to assess possible correlations among the relative abundance of each phycobiont, their individual physiological responses and that of the entire thallus. Unexpectedly, Pb decreased ROS and lipid peroxidation in thalli and its phycobionts, associated with a lower chlorophyll autofluorescence. Each phycobiont showed a particular pattern, but the oxidative response of the thallus paralleled the TR1's, agreeing with the genetic identification of this strain as the predominant phycobiont. We conclude that: (1) the lichen oxidative behaviour seems to be modulated by the predominant phycobiont and (2) Pb evokes in R. farinacea and its phycobionts strong mechanisms to neutralize its own oxidant effects along with those of rehydration

    Low intensity vs. self-guided Internet-delivered psychotherapy for major depression: A multicenter, controlled, randomized study

    Get PDF
    Background: Major depression will become the second most important cause of disability in 2020. Computerized cognitive-behaviour therapy could be an efficacious and cost-effective option for its treatment. No studies on cost-effectiveness of low intensity vs self-guided psychotherapy has been carried out. The aim of this study is to assess the efficacy of low intensity vs self-guided psychotherapy for major depression in the Spanish health system. Methods: The study is made up of 3 phases: 1.- Development of a computerized cognitive-behaviour therapy for depression tailored to Spanish health system. 2.- Multicenter controlled, randomized study: A sample (N=450 patients) with mild/moderate depression recruited in primary care. They should have internet availability at home, not receive any previous psychological treatment, and not suffer from any other severe somatic or psychological disorder. They will be allocated to one of 3 treatments: a) Low intensity Internet-delivered psychotherapy + improved treatment as usual (ITAU) by GP, b) Self-guided Internet-delivered psychotherapy + ITAU or c) ITAU. Patients will be diagnosed with MINI psychiatric interview. Main outcome variable will be Beck Depression Inventory. It will be also administered EuroQol 5D (quality of life) and Client Service Receipt Inventory (consume of health and social services). Patients will be assessed at baseline, 3 and 12 months. An intention to treat and a per protocol analysis will be performed. Discussion: The comparisons between low intensity and self-guided are infrequent, and also a comparative economic evaluation between them and compared with usual treatment in primary. The strength of the study is that it is a multicenter, randomized, controlled trial of low intensity and self-guided Internet-delivered psychotherapy for depression in primary care, being the treatment completely integrated in primary care setting

    An Early Neolithic House in the Foothills:A Case Study of Pottery and Lithic Artefacts from the Biskupice Site 18 (Wieliczka Foothills, Southern Poland)

    Get PDF
    Highlights‱Biskupice site (S Poland) represents the late Ćœeliezovce phase (5300 to 5000 BCE).‱Pottery was produced locally, and showed a use of animal fats for cooking.‱The face vessel was of local origin, but influenced by Transcarpathian style.‱Obsidian artefacts originated from the Carpathian 1a/1b chemical type, S-E Slovakia.‱Transcarpathian contacts between LBK and BĂŒkk culture were discussed.AbstractThe paper presents a comprehensive analysis of pottery and lithic materials found in archaeological features associated with an Early Neolithic house from Biskupice (southern Poland) to shed light on exchange networks of the first farmers in Central Europe. The research began with the discovery of a unique fragment of a face vessel made in the Ćœeliezovce style, a motif primarily found in Moravia and north-eastern Austria. Therefore, specialised analyses were undertaken to determine whether the Biskupice fragment was locally produced or originated from areas south of the Sudetes and Carpathians. The study involved an examination of raw clay material and the technology used to create the anthropomorphic vessel, aiming to establish its provenance (local production versus import). Petrographic methods were employed to analyse a diverse group of vessel types for comparison. Additionally, a selected group of pottery fragments, including the face vessel, underwent lipid residue analysis to determine their potential use. The combination of microscopic examinations and lipid residues analysis was utilised to study the link between the physical properties and function of the vessels. Finally, the archaeological context of other artifacts from the same house, including lithic assemblages, was investigated to determine the presence of both local and imported raw materials in Biskupice. The main conclusion of the study indicates local production of pottery, including the face vessel, and lithic implements. Conversely, a Transcarpathian transfer of some technological and decorative ideas, as well as imports of raw material such as obsidian, were confirmed
    • 

    corecore