Recent Submissions

  • Journal Article

    Staatliche Eingriffe in die Lebensmittelwahl: Welche klimapolitischen Instrumente unterstützt die Bevölkerung? 

    Lemken, Dominic; Kraus, Katharina; Nitzko, Sina; Spiller, Achim
    GAIA - Ecological Perspectives for Science and Society 2018; 27(4) p.363-372
    Staatliche Eingriffe in den Lebensmittelkonsum der Deutschen sind im europäischen Vergleich eher selten. Politiker(innen) empfinden wohl Lenkungssteuern- oder Werbeverbote als unpopulär. Konkrete Maßnahmen zum Klimaschutz, etwa eine Klimasteuer auf importierte Flugwaren, stoßen jedoch auf breite Zustimmung und könnten durchaus zu Klimazielen beitragen. In view of climate change, policy approaches addressing the consumption side of nutrition are becoming increasingly relevant to lowering greenhouse gas (GHG) emissions. Yet, adequate policy instruments can be risky. They interfere with individual freedom of choice and can thus be unpopular. This study investigates the social acceptance of governmental interventions. The study explores four types of climate policy instruments of increasing depth of intervention: 1. information and education, 2. nudging, 3. taxation, 4. bans. Information and nudging are met with the largest degree of approval. Assuming that acceptance will decrease with the depth of intervention, the equally critical perception of taxation and bans is an exception. Apart from the depth of intervention, social acceptance also depends on the field of action. For instance, taxation of airfreight products would be widely accepted. The conclusion explores nutrition policy options motivated by climate policy considerations.
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  • Journal Article

    Word-object and action-object association learning across early development 

    Eiteljoerge, Sarah F. V.; Adam, Maurits; Elsner, Birgit; Mani, Nivedita
    PLOS ONE 2019; 14(8): Art. e0220317
    Successful communication often involves comprehension of both spoken language and observed actions with and without objects. Even very young infants can learn associations between actions and objects as well as between words and objects. However, in daily life, children are usually confronted with both kinds of input simultaneously. Choosing the critical information to attend to in such situations might help children structure the input, and thereby, allow for successful learning. In the current study, we therefore, investigated the developmental time course of children's and adults' word and action learning when given the opportunity to learn both word-object and action-object associations for the same object. All participants went through a learning phase and a test phase. In the learning phase, they were presented with two novel objects which were associated with a distinct novel name (e.g., "Look, a Tanu") and a distinct novel action (e.g., moving up and down while tilting sideways). In the test phase, participants were presented with both objects on screen in a baseline phase, then either heard one of the two labels or saw one of the two actions in a prime phase, and then saw the two objects again on screen in a recognition phase. Throughout the trial, participants' target looking was recorded to investigate whether participants looked at the target object upon hearing its label or seeing its action, and thus, would show learning of the word-object and action-object associations. Growth curve analyses revealed that 12-month-olds showed modest learning of action-object associations, 36-month-olds learned word-object associations, and adults learned word-object and action-object associations. These results highlight how children attend to the different information types from the two modalities through which communication is addressed to them. Over time, with increased exposure to systematic word-object mappings, children attend less to action-object mappings, with the latter potentially being mediated by word-object learning even in adulthood. Thus, choosing between different kinds of input that may be more relevant in their rich environment encompassing different modalities might help learning at different points in development.
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  • Journal Article

    Measures for sustainable forest management in the tropics – A tree-ring based case study on tree growth and forest dynamics in a Central Amazonian lowland moist forest 

    Worbes, Martin; Schöngart, Jochen
    PLOS ONE 2019; 14(8): Art. e0219770
    The conservation of tropical forests is recognized as one of the most important challenges for forestry, ecology and politics. Besides strict protection, the sustainable management of natural forests should be enhanced as a key part of the foundation for the maintenance of tropical rain forest ecosystems. Due to methodological reasons it has been complicated to attain reliable growth data to plan sustainable felling cycles and rotation periods. Tree ring analyses enable the estimation of growth rates over the entire life span of trees and their age as well as giving hints from forest dynamics in previous centuries. For tree ring analysis, stem disk samples were taken from three important commercial tree species (Cariniana micrantha, Caryocar villosum and Manilkara huberi) in the upland (terra firme) forests of the Precious Woods Amazon logging company near Itacoatiara, Brazil. Based on radiocarbon estimates of individual growth zones, the annual nature of tree rings was proven for the three species. Tree rings were measured and the results used together with height estimates to model diameter, height and volume growth. The age of the eldest tree, a C. micrantha, was 585 yrs with 165 cm in diameter. The species' diameter increments range from 0.20±0.12 cm yr-1 to 0.29±0.08 cm yr-1. At first sight, this is considerably lower than increments reported from other Amazonian or African timber species. Considering the respective wood density there is no significant difference in growth performance of dominant timber species across continents. The interpretation of lifetime tree ring curves indicate differences in shadow tolerance among species, the persistence of individuals in the understory for up to 150 years and natural stand dynamics without major disturbances. Management criteria should be adapted for the measured growth rates as they differed considerably from the Brazilian standards fixed by laws (felling cycle of 25-35 years and a common minimum logging diameter of 50 cm). Felling cycles should be increased to 32-51 years and minimum logging diameters to 63-123 cm depending on the species.
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  • Journal Article

    True eddy accumulation trace gas flux measurements: proof of concept 

    Siebicke, Lukas; Emad, Anas
    Atmospheric Measurement Techniques 2019; 12(8) p.4393-4420
    Micrometeorological methods to quantify fluxes of atmospheric constituents are key to understanding and managing the impact of land surface sources and sinks on air quality and atmospheric composition. Important greenhouse gases are water vapor, carbon dioxide, methane, and nitrous oxide. Further important atmospheric constituents are aerosols, which impact air quality and cloud formation, and volatile organic compounds. Many atmospheric constituents therefore critically affect the health of ecosystems and humans, as well as climate. The micrometeorological eddy covariance (EC) method has evolved as the method of choice for CO2 and water vapor flux measurements using fast-response gas analyzers. While the EC method has also been used to measure other atmospheric constituents including methane, nitrous oxide, and ozone, the often relatively small fluxes of these constituents over ecosystems are much more challenging to measure using eddy covariance than CO2 and water vapor fluxes. For many further atmospheric constituents, eddy covariance is not an option due to the lack of sufficiently accurate and fast-response gas analyzers. Therefore, alternative flux measurement methods are required for the observation of atmospheric constituent fluxes for which no fast-response gas analyzers exist or which require more accurate measurements. True eddy accumulation (TEA) is a direct flux measurement technique capable of using slow-response gas analyzers. Unlike its more frequently used derivative, known as the relaxed eddy accumulation (REA) method, TEA does not require the use of proxies and is therefore superior to the indirect REA method. The true eddy accumulation method is by design ideally suited for measuring a wide range of trace gases and other conserved constituents transported with the air. This is because TEA obtains whole air samples and is, in combination with constituent-specific fast or slow analyzers, a universal method for conserved scalars. Despite the recognized value of the method, true eddy accumulation flux measurements remain very challenging to perform as they require fast and dynamic modulation of the air sampling mass flow rate proportional to the magnitude of the instantaneous vertical wind velocity. Appropriate techniques for dynamic mass flow control have long been unavailable, preventing the unlocking of the TEA method's potential for more than 40 years. Recently, a new dynamic and accurate mass flow controller which can resolve turbulence at a frequency of 10 Hz and higher has been developed by the first author. This study presents the proof of concept that practical true eddy accumulation trace gas flux measurements are possible today using dynamic mass flow control, advanced real-time processing of wind measurements, and fully automatic gas handling. We describe setup and methods of the TEA and EC reference flux measurements. The experiment was conducted over grassland and comprised 7 d of continuous flux measurements at 30 min flux integration intervals. The results show that fluxes obtained by TEA compared favorably to EC reference flux measurements, with coefficients of determination of up to 86 % and a slope of 0.98. We present a quantitative analysis of uncertainties of the mass flow control system, the gas analyzer, and gas handling system and their impact on trace gas flux uncertainty, the impact of different approaches to coordinate rotation, and uncertainties of vertical wind velocity measurements. Challenges of TEA are highlighted and solutions presented. The current results are put into the context of previous works. Finally, based on the current successful proof of concept, we suggest specific improvements towards long-term and reliable true eddy accumulation flux measurements.
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  • Journal Article

    Impact of a phytogenic feed additive on growth performance, feed intake, and carcass traits of finishing steers 

    Brand, Tassilo; Hünerberg, Martin; McAllister, Tim A; He, Maolong; Saleem, Atef M; Shen, Yizhao; Miller, Bryan; Yang, Wenzhu
    Translational Animal Science 2019; 3(4)
    The purpose of this study was to evaluate the effect of a phytogenic feed additive (Digestarom [DA]; Biomin, Getzersdorf, Austria) on growth performance, feed intake, carcass traits, fatty acid composition, and liver abscesses of finishing steers. One hundred twenty Angus × Charolais crossbred steers (488 ± 26.5 kg) were used in a 110-d feeding experiment. Steers were blocked by weight and randomly assigned to 12 pens with 10 steers per pen. Each pen was allocated to one of three diets. Each diet contained 86.5% barley, 10.0% barley silage, and 3.5% vitamin and mineral supplement on a dry matter (DM) basis. The diets contained 0, 0.05, and 0.1 g DA/kg complete diet (DM basis), to achieve average daily DA intakes of 0 (control), 0.5 (LowDA), and 1.0 g (HighDA) per steer. Diets were prepared once daily and provided ad libitum. Two pens per treatment were equipped to record individual feed intake behavior. Steers were weighed every 28 d and carcass traits and liver scores were recorded at slaughter. Dry matter intake (average: 9.34 kg/d) did not differ (P > 0.05) among diets. Average daily gain tended to increase linearly as DA increased (control: 1.82; LowDA: 1.87; and HighDA: 1.95 kg/d; P < 0.09), but gain:feed ratio was not affected. Supplementation of DA affected longissimus muscle area quadratically (P = 0.05) with the largest area observed for LowDA. However, dressing percentage decreased linearly in response to increasing level of DA (P < 0.01). Total abscessed livers were not affected, whereas proportion of severe liver abscesses was numerically lower with DA (30.8% and 42.5% for LowDA and HighDA) compared to the control (50%).
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  • Journal Article

    CCDC42 Localizes to Manchette, HTCA and Tail and Interacts With ODF1 and ODF2 in the Formation of the Male Germ Cell Cytoskeleton 

    Tapia Contreras, Constanza; Hoyer-Fender, Sigrid
    Frontiers in Cell and Developmental Biology 2019; 7: Art. 151
    Terminal differentiation of male germ cells into functional spermatozoa requires shaping and condensation of the nucleus as well as the formation of sperm-specific structures. A transient microtubular structure, the manchette, is mandatory for sperm head shaping and the development of the connecting piece and the sperm tail. The connecting piece or head-to-tail coupling apparatus (HTCA) mediates the tight linkage of sperm head and tail causing decapitation and infertility when faulty. Using mice as the experimental model, several proteins have already been identified affecting the linkage complex, manchette or tail formation when missing. However, our current knowledge is far too rudimentary to even draft an interacting protein network. Depletion of the major outer dense fiber protein 1 (ODF1) mainly caused decapitation and male infertility but validated binding partners collaborating in the formation of sperm-specific structures are largely unknown. Amongst all candidate proteins affecting the HTCA when missing, the structural protein CCDC42 attracted our attention. The coiled-coil domain containing 42 (CCDC42) is important for HTCA and sperm tail formation but is otherwise largely uncharacterized. We show here that CCDC42 is expressed in spermatids and localizes to the manchette, the connecting piece and the tail. Beyond that, we show that CCDC42 is not restricted to male germ cells but is also expressed in somatic cells in which it localizes to the centrosome. Although centrosomal and sperm tail location seems to be irrespective of ODF1 we asked whether both proteins may form an interacting network in the male germ cell.We additionally considered ODF2, a prevalent protein involved in the formation of spermatid-specific cytoskeletal structures, as a putative binding partner. Our data depict for the first time the subcellular location of CCDC42 in spermatids and deepen our knowledge about the composition of the spermatid/sperm-specific structures. The presence of CCDC42 in the centrosome of somatic cells together with the obvious restricted male-specific phenotype when missing strongly argues for a compensatory function by other still unknown proteins most likely of the same family.
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  • Journal Article

    On the Competition Between Electron Autodetachment and Dissociation of Molecular Anions 

    Marowsky, Gerd; Troe, Jürgen; Viggiano, Albert A.
    Journal of The American Society for Mass Spectrometry
    We treat the competition between autodetachment of electrons and unimolecular dissociation of excited molecular anions as a rigid-/loose-activated complex multichannel reaction system. To start, the temperature and pressure dependences under thermal excitation conditions are represented in terms of falloff curves of separated single-channel processes within the framework of unimolecular reaction kinetics. Channel couplings, caused by collisional energy transfer and "rotational channel switching" due to angular momentum effects, are introduced afterward. The importance of angular momentum considerations is stressed in addition to the usual energy treatment. Non-thermal excitation conditions, such as typical for chemical activation and complex-forming bimolecular reactions, are considered as well. The dynamics of excited SF6- anions serves as the principal example. Other anions such as CF3- and POCl3- are also discussed.
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  • Journal Article

    Small Neotropical primates promote the natural regeneration of anthropogenically disturbed areas 

    Heymann, Eckhard W.; Culot, Laurence; Knogge, Christoph; Smith, Andrew C.; Tirado Herrera, Emérita R.; Müller, Britta; Stojan-Dolar, Mojca; Lledo Ferrer, Yvan; Kubisch, Petra; Kupsch, Denis; et al.
    Slana, DarjaKoopmann, Mareike LenaZiegenhagen, BirgitBialozyt, RonaldMengel, ChristinaHambuckers, JulienHeer, Katrin
    Scientific Reports 2019; 9(1): Art. 10356
    Increasingly large proportions of tropical forests are anthropogenically disturbed. Where natural regeneration is possible at all, it requires the input of plant seeds through seed dispersal from the forest matrix. Zoochorous seed dispersal - the major seed dispersal mode for woody plants in tropical forests - is particularly important for natural regeneration. In this study, covering a period of more than 20 years, we show that small New World primates, the tamarins Saguinus mystax and Leontocebus nigrifrons, increase their use of an anthropogenically disturbed area over time and disperse seeds from primary forest tree species into this area. Through monitoring the fate of seeds and through parentage analyses of seedlings of the legume Parkia panurensis from the disturbed area and candidate parents from the primary forest matrix, we show that tamarin seed dispersal is effective and contributes to the natural regeneration of the disturbed area.
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  • Journal Article

    Mycotoxigenic Fungi and Mycotoxins in Agricultural Crop Commodities in the Philippines: A Review 

    Balendres, Mark Angelo O.; Karlovsky, Petr; Cumagun,Christian Joseph R.
    Foods 2019; 8(7): Art. 249
    The tropical, warm, and humid conditions that are favorable to the growth and development of mycotoxigenic fungi put the Philippines at a high risk of mycotoxin contamination. To date, seven mycotoxigenic Aspergillus species, four Fusarium species, and one Penicillium species have been isolated from various agricultural crop commodities in the country. There are five mycotoxin groups (aflatoxin, fumonisin, ochratoxin, nivalenol, and zearalenone) that have been detected in both the raw form and the by-products of major crops grown in the country. Since the first scientific report of aflatoxin contamination in the Philippines in 1972, new information has been generated on mycotoxins and mycotoxigenic fungi, but little has been known of other mycotoxins until the last two decades. Further, despite the increase in the understanding of mycotoxigenic fungi and mycotoxins in the country, very limited knowledge exists on practices and measures that control both the fungi and the toxins. This paper reviews the current literature on mycotoxigenic fungi and mycotoxins in the Philippines with emphasis on the last two decades and on other mycotoxins.
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  • Journal Article

    Consistency of co-occurring actions influences young children’s word learning 

    Eiteljoerge, Sarah F. V.; Adam, Maurits; Elsner, Birgit; Mani, Nivedita
    Royal Society Open Science 2019; 6(8): Art. 190097
    Communication with young children is often multimodal in nature, involving, for example, language and actions. The simultaneous presentation of information from both domains may boost language learning by highlighting the connection between an object and a word, owing to temporal overlap in the presentation of multimodal input. However, the overlap is not merely temporal but can also covary in the extent to which particular actions co-occur with particular words and objects, e.g. carers typically produce a hopping action when talking about rabbits and a snapping action for crocodiles. The frequency with which actions and words co-occurs in the presence of the referents of these words may also impact young children’s word learning. We, therefore, examined the extent to which consistency in the co-occurrence of particular actions and words impacted children’s learning of novel word–object associations. Children (18 months, 30 months and 36–48 months) and adults were presented with two novel objects and heard their novel labels while different actions were performed on these objects, such that the particular actions and word–object pairings always co-occurred (Consistent group) or varied across trials (Inconsistent group). At test, participants saw both objects and heard one of the labels to examine whether participants recognized the target object upon hearing its label. Growth curve models revealed that 18-month-olds did not learn words for objects in either condition, and 30-month-old and 36- to 48-month-old children learned words for objects only in the Consistent condition, in contrast to adults who learned words for objects independent of the actions presented. Thus, consistency in the multimodal input influenced word learning in early childhood but not in adulthood. In terms of a dynamic systems account of word learning, our study shows how multimodal learning settings interact with the child’s perceptual abilities to shape the learning experience.
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  • Journal Article

    Origin and Consequences of Chromosomal Inversions in the virilis Group of Drosophila 

    Reis, Micael; Vieira, Cristina P.; Lata, Rodrigo; Posnien, Nico; Vieira, Jorge
    Genome Biology and Evolution 2018; 10(12) p.3152-3166
    In Drosophila, large variations in rearrangement rate have been reported among different lineages and among Muller's elements. Nevertheless, the mechanisms that are involved in the generation of inversions, their increase in frequency, as well as their impact on the genome are not completely understood. This is in part due to the lack of comparative studies on species distantly related to Drosophila melanogaster. Therefore, we sequenced and assembled the genomes of two species of the virilis phylad (Drosophila novamexicana [15010-1031.00] and Drosophila americana [SF12]), which are diverging from D. melanogaster for more than 40 Myr. Based on these data, we identified the precise location of six novel inversion breakpoints. A molecular characterization provided clear evidence that DAIBAM (a miniature inverted-repeat transposable element) was involved in the generation of eight out of the nine inversions identified. In contrast to what has been previously reported for D. melanogaster and close relatives, ectopic recombination is thus the prevalent mechanism of generating inversions in species of the virilis phylad. Using pool-sequencing data for three populations of D. americana, we also show that common polymorphic inversions create a high degree of genetic differentiation between populations for chromosomes X, 4, and 5 over large physical distances. We did not find statistically significant differences in expression levels between D. americana (SF12) and D. novamexicana (15010-1031.00) strains for the three genes surveyed (CG9588, Fig 4, and fab1) flanking three inversion breakpoints.
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  • Journal Article

    Cloudy with a Chance of Insights: Context Dependent Gene Regulation and Implications for Evolutionary Studies 

    Buchberger; Reis; Lu; Posnien
    Genes 2019; 10(7): Art. 492
    Research in various fields of evolutionary biology has shown that divergence in gene expression is a key driver for phenotypic evolution. An exceptional contribution of cis-regulatory divergence has been found to contribute to morphological diversification. In the light of these findings, the analysis of genome-wide expression data has become one of the central tools to link genotype and phenotype information on a more mechanistic level. However, in many studies, especially if general conclusions are drawn from such data, a key feature of gene regulation is often neglected. With our article, we want to raise awareness that gene regulation and thus gene expression is highly context dependent. Genes show tissue- and stage-specific expression. We argue that the regulatory context must be considered in comparative expression studies.
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  • Journal Article

    Bis-naphthopyrone pigments protect filamentous ascomycetes from a wide range of predators 

    Xu, Yang; Vinas, Maria; Alsarrag, Albatol; Su, Ling; Pfohl, Katharina; Rohlfs, Marko; Schäfer, Wilhelm; Chen, Wei; Karlovsky, Petr
    Nature Communications 2019; 10(1): Art. 3579
    It is thought that fungi protect themselves from predation by the production of compounds that are toxic to soil-dwelling animals. Here, we show that a nontoxic pigment, the bisnaphthopyrone aurofusarin, protects Fusarium fungi from a wide range of animal predators. We find that springtails (primitive hexapods), woodlice (crustaceans), and mealworms (insects) prefer feeding on fungi with disrupted aurofusarin synthesis, and mealworms and springtails are repelled by wheat flour amended with the fungal bis-naphthopyrones aurofusarin, viomellein, or xanthomegnin. Predation stimulates aurofusarin synthesis in several Fusarium species and viomellein synthesis in Aspergillus ochraceus. Aurofusarin displays low toxicity in mealworms, springtails, isopods, Drosophila, and insect cells, contradicting the common view that fungal defence metabolites are toxic. Our results indicate that bisnaphthopyrones are defence compounds that protect filamentous ascomycetes from predators through a mechanism that does not involve toxicity.
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  • Journal Article

    Prokaryotic Diversity and Community Patterns in Antarctic Continental Shelf Sponges 

    Steinert, Georg; Wemheuer, Bernd; Janussen, Dorte; Erpenbeck, Dirk; Daniel, Rolf; Simon, Meinhard; Brinkhoff, Thorsten; Schupp, Peter J.
    Frontiers in Marine Science 2019; 6: Art. 297
    Marine sponges (Phylum Porifera) are globally distributed within marine and freshwater ecosystems. In addition, sponges host dense and diverse prokaryotic communities, which are potential sources of novel bioactive metabolites and other complex compounds. Those sponge-derived natural products can span a broad spectrum of bioactivities, from antibacterial and antifungal to antitumor and antiviral compounds. However, most analyses concerning sponge-associated prokaryotes have mainly focused on conveniently accessible relatively shallow sampling locations for sponges. Hence, knowledge of community composition, host-relatedness and biotechnological potential of prokaryotic associations in temperate and cold-water sponges from greater depths (mesophotic to mesopelagic zones) is still scarce. Therefore, we analyzed the prokaryotic community diversity of four phylogenetically divergent sponge taxa from mesophotic to mesopelagic depths of Antarctic shelf at different depths and locations in the region of the South Shetland Islands using 16S rRNA gene ampliconbased sequencing. In addition, we predicted functional profiles applying Tax4Fun from metagenomic 16S rRNA gene data to estimate their biotechnological capability and possible roles as sources of novel bioactive compounds. We found indications that cold and deep-water sponges exhibit host-specific prokaryotic communities, despite different sampling sites and depths. Functional prediction analysis suggests that the associated prokaryotes may enhance the roles of sponges in biodegradation processes of xenobiotics and their involvement in the biosynthesis of secondary metabolites.
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  • Journal Article

    Transit least-squares survey. II. Discovery and validation of 17 new sub- to super-Earth-sized planets in multi-planet systems from K2 

    Heller, René; Hippke, Michael; Rodenbeck, Kai
    Astronomy & Astrophysics 2019; 627: Art. A66
    The extended Kepler mission (K2) has revealed more than 500 transiting planets in roughly 500 000 stellar light curves. All of these were found either with the box least-squares algorithm or by visual inspection. Here we use our new transit least-squares (TLS) algorithm to search for additional planets around all K2 stars that are currently known to host at least one planet. We discover and statistically validate 17 new planets with radii ranging from about 0.7 Earth radii (R ) to roughly 2:2 R and a median radius of 1:18 R . EPIC 201497682.03, with a radius of 0:692+0:059 􀀀0:048 R , is the second smallest planet ever discovered with K2. The transit signatures of these 17 planets are typically 200 ppm deep (ranging from 100 ppm to 2000 ppm), and their orbital periods extend from about 0.7 d to 34 d with a median value of about 4 d. Fourteen of these 17 systems only had one known planet before, and they now join the growing number of multi-planet systems. Most stars in our sample have subsolar masses and radii. The small planetary radii in our sample are a direct result of the higher signal detection e ciency that TLS has compared to box-fitting algorithms in the shallow-transit regime. Our findings help in populating the period-radius diagram with small planets. Our discovery rate of about 3.7% within the group of previously known K2 systems suggests that TLS can find over 100 additional Earth-sized planets in the data of the Kepler primary mission.
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  • Journal Article

    Landscape Transformations in Rapidly Developing Peri-urban Areas of Accra, Ghana: Results of 30 years 

    Ashiagbor, George; Amoako, Clifford; Asabere, Stephen B.; Quaye-Ballard, Jonathan A.
    Open Geosciences 2019; 11(1) p.172-182
    Beyond the loss of peri-urban agricultural and forested land as a result of built-up expansion, not much information exists on the changes in the structure of the peri-urban landscape in Ghana. The aim of this paper is to examine the extent to which urban expansion is driving changes in landscape structure of the peri-urban fringes of Accra. We submit that rapid peri-urbanisation will fragment the existing agricultural and forested landscape with consequent ecological, socio-economic and urban governance implications. Using Landsat satellite images for the years 1985, 1991, 2002 and 2015 the study area was classified into four land cover classes. The study adopted the use of Urban Intensity Index (UII) and the Annual Rate of Urbanization (R) as measures of urbanization. Edge density (ED), largest patch index (LPI) and Aggregation index (AI) were used as proxies to measure landscape structural transformations. The study reveals substantial reductions and fragmentation in agricultural lands, riverine and open forests, while there has been over 200 percent increase in built-up areas. Beyond these revelations in spatiotemporal changes in landscape structure, the paper points to the ecological implications of the changes, and three key socio-economic and urban governance implications.
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  • Journal Article

    Water Transfer Between Bamboo Culms in the Period of Sprouting 

    Fang, Dongming; Mei, Tingting; Röll, Alexander; Hölscher, Dirk
    Frontiers in Plant Science 2019; 10: Art. 786
    Bamboo culms are connected to neighboring culms via rhizomes, which enable resource exchange between culms. We assessed water transfer between established and neighboring, freshly sprouted culms by thermal dissipation probes (TDP) inserted into culms and the connecting rhizome. During the early phase of sprouting, highest sap flux densities in freshly sprouted culms were observed at night, whereas neighboring established culms had high sap flux densities during daytime. After leaf flushing on freshly sprouted culms, the nighttime peaks disappeared and culms switched to the diurnal sap flux patterns with daytime maxima as observed in established culms. TDP in rhizomes indicated water flowing from the established to the freshly sprouted culms. When the established culms of a clump were cut, freshly sprouted culms without leaves reduced sap flux densities rates by 79%. Our findings thus suggest that bamboos exchange water via rhizomes and that nighttime fluxes are highly important for the support of freshly sprouted culms. The (water) resource support may facilitate the very fast growth of the bamboo shoots, and enable the colonizing of new places.
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  • Journal Article

    Isotomidae of Japan and Asiatic part of Russia. II. The genus Tetracanthella of the Far East 

    Potapov, Mikhail; Brinev, Alexey; Sun, Xin
    ZooKeys 2019; 855 p.31-54: Art.
    The paper considers new and little-known species of the genus Tetracanthella distributed in the Far East of Russia and in Japan. Sensillar chaetotaxy and labial palp, two less known morphological characters for the genus, are discussed. Two new species T.annulata sp. nov. and T.tardoki sp. nov. are described; T.manschurica Kutyreva, 1980 and T czernovae Kutyreva, 1980 are redescribed. For the latter species a lectotype and paralectotypes are designated. Remarks are provided for T.sylvatica Yosii, 1939. A second undescribed species is recorded for Japan. New records for T.orientalis Martynova, 1977 and T.sibirica Deharveng, 1987 are listed.
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  • Journal Article

    Leaf mechanisms involved in the response of Cydonia oblonga trees to water stress and recovery 

    Griñán, I.; Rodríguez, P.; Nouri, H.; Wang, R.; Huang, G.; Morales, D.; Corell, M.; Pérez-López, D.; Centeno, A.; Martin-Palomo, M.J.; et al.
    Hernández, F.Torrecillas, A.Galindo, A.
    Agricultural Water Management 2019; 221 p.66-72
    Quince tree (Cydonia oblonga Mill.) is known for bearing fruits that are rich in nutrients and health-promoting compounds while requiring low inputs of agrochemicals, and maintenance, but no information exists on the mechanisms developed at the level of leaf water relations to confront water stress and recovery. For this reason, the purpose of the present study was to identify the strategy (isohydric or anisohydric) by which quince plants cope with water stress and to further elucidate the resistance mechanisms developed in response to water stress and during recovery. In summer 2016, field-grown own rooted 17-years old quince trees (cv. BA-29) were subjected to two irrigation treatments. Control (T0) plants were drip irrigated (105% ETo) to ensure non-limiting soil water conditions, while T1 plants were irrigated at the same level as used in T0, except that irrigation was withheld for 42 days during the linear fruit growth phase, after which irrigation returned to the levels of T0 (recovery period). During the experimental period, T0 and T1 received a total of 374 and 143 mm water, respectively, including rain water. The quince trees exhibited extreme anisohydric behaviour under the experimental conditions. As water stress developed and during the recovery period, the plants exhibited high hydraulic conductivity, probably the result of resistance to cavitation. From the beginning of water stress to the time of maximum water stress, leaf turgor was maintained, possibly due to active osmotic adjustment (stress tolerance mechanism). This leaf turgor maintenance may have contributed to the high leaf conductance, and, therefore, good leaf productivity. The low quince leaf apoplastic water fraction under water stress could be considered as another drought tolerance characteristic because if the accumulation of water in the apoplasm is avoided a steeper gradient in water potential between the leaf and the soil can take place under water stress, thus favouring water absorption.
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  • Journal Article

    Magnetic fields in M dwarfs from the CARMENES survey 

    Shulyak, D.; Reiners, A.; Nagel, E.; Tal-Or, L.; Caballero, J. A.; Zechmeister, M.; Béjar, V. J. S.; Cortés-Contreras, M.; Martin, E. L.; Kaminski, A.; et al.
    Ribas, I.Quirrenbach, A.Amado, P. J.Anglada-Escudé, G.Bauer, F. F.Dreizler, S.Guenther, E. W.Henning, T.Jeffers, S. V.Kürster, M.Lafarga, M.Montes, D.Morales, J. C.Pedraz, S.
    Astronomy & Astrophysics 2019; 626(A86)
    Context. M dwarfs are known to generate the strongest magnetic fields among main-sequence stars with convective envelopes, but we are still lacking a consistent picture of the link between the magnetic fields and underlying dynamo mechanisms, rotation, and activity. Aims. In this work we aim to measure magnetic fields from the high-resolution near-infrared spectra taken with the CARMENES radial-velocity planet survey in a sample of 29 active M dwarfs and compare our results against stellar parameters. Methods. We used the state-of-the-art radiative transfer code to measure total magnetic flux densities from the Zeeman broadening of spectral lines and filling factors. Results. We detect strong kG magnetic fields in all our targets. In 16 stars the magnetic fields were measured for the first time. Our measurements are consistent with the magnetic field saturation in stars with rotation periods P < 4 d. The analysis of the magnetic filling factors reveal two different patterns of either very smooth distribution or a more patchy one, which can be connected to the dynamo state of the stars and/or stellar mass. Conclusions. Our measurements extend the list ofMdwarfs with strong surface magnetic fields. They also allow us to better constrain the interplay between the magnetic energy, stellar rotation, and underlying dynamo action. The high spectral resolution and observations at near-infrared wavelengths are the beneficial capabilities of the CARMENES instrument that allow us to address important questions about the stellar magnetism
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