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931.
Tatjana Krama Indrikis Krams† & Kristne Igaune† 《Ethology : formerly Zeitschrift fur Tierpsychologie》2008,114(7):656-661
Predation is one of the main factors responsible for winter mortality in small birds. Contact vocalizations of crested tits ( Parus cristatus ) can be divided into two categories: long- and short-range communication calls. The long-range calls are loud, frequency-modulated trills, which are well suited for acoustic communication over long distances. The short-range calls, in contrast, are soft, high-pitched tones, which are strongly attenuated as they radiate through the environment. As the predation cost in this species is mostly associated with the use of loud calls, we investigated whether crested tits adjust the use of loud trill-calls and of soft seet-calls to changes in habitat safety. We arranged two feeding sites that differed with respect to predicted safety, and observed the utterance of loud trill-calls and soft seet-calls. Calling rates of the loud trill-calls were highest when male crested tits foraged at the safe site. The loud trill-calls were given significantly less often while visiting risky feeders placed just a few metres away from the safe sites. The soft seet-calls were uttered both at risky and safe feeders at similar rates. This study suggests that the long-range part of contact communication in crested tits is strongly affected by the level of perceived predation risk. In accordance with the data on hearing ability of predators, dominant male crested tits decrease their exposure to predation in risky habitats by choosing a less risky type of communication with high-pitched sounds. 相似文献
932.
Mira Starović Slobodan Kuzmanović Veljko Gavrilović Goran Aleksić Tatjana Popović Saša Stojanović Dragana Jošić 《Journal of Phytopathology》2012,160(11-12):758-760
Plants of alfalfa (Medicago sativa) exhibiting general stunting, proliferation and phyllody associated with leaf yellowing and reddening were observed in three localities of Central Serbia. Phytoplasma strains belonging to 16SrIII‐B and 16SrXII‐A groups were detected and identified by RFLP and sequence analysis of 16S rDNA. Stolbur phytoplasma tuf gene RFLP analysis showed the presence of the TufAY‐b‐type phytoplasma subgroup in 80% of symptomatic samples. This is the first report of 16SrIII‐B and 16SrXII‐A phytoplasma groups affecting alfalfa in Serbia. 相似文献
933.
Tatjana Čelik 《Journal of Insect Conservation》2013,17(5):865-876
The oviposition preferences of Leptidea morsei at the western border of its range (SE Slovenia) were studied with the aim of integrating this information into species habitat management recommendations. The characteristics of egg-laying habitat were examined at the landscape, patch, plant and leaf levels. Because sightings of adults in the field were infrequent, intensive searching for previously laid eggs on Lathyrus niger plants was chosen as the survey method. The main oviposition habitats of L. morsei in Slovenia were found to be the forest edges and light stands of thermophilous oak, oak-hornbeam and mesic beech forests (landscape level). The egg-laying sites were L. niger plants growing individually or in small stands, and oriented mostly towards W, SW, and S. The oviposition plants were between 33 and 120 cm high, with those growing in half to full shade preferred. Eggs were deposited singly, mainly on the underside of leaflets of terminal leaves, located mostly on the top quarter of plants irrespective of their height and growth form. The most important factors affecting egg-placement are sun exposure and the size of L. niger stands at ovipositing sites (patch level), leaf exposure on the plant in vertical and horizontal directions (plant level), leaf age and the leaf parts where the risk of leaf and egg desiccation is lower (leaf level). Management strategies for the main egg-laying habitats of the species are proposed. 相似文献
934.
Sanja Milovi Ivan Stankovi Dejan Nikoli Jelena Radovi Marina Kolundi Vesna Nikoli Tatjana Stanojkovi Slavica Petovi Tatjana Kundakovi‐Vasovi 《化学与生物多样性》2019,16(10)
Three seaweeds (Halimeda tuna, Codium bursa and Cystoseira barbata) and one seagrass (Cymodocea nodosa) were collected from the Coast of Montenegro, Gulf of Boka Kotorska and their chemical analysis was performed. In seagrass C. nodosa, three phenolic compounds were identified (diosmetin 7‐sulfate, caftaric and coutaric acid). The content of β‐glucan, fatty acids, sterols and micro‐ and macro‐elements were investigated among all samples. The highest content of β‐glucan was detected in C. nodosa seagrass (13.04±0.42 g/100 g). The highest polyunsaturated fatty acids (PUFAs) level was reported in C. barbata, the brown alga (7.157 mg/g), which also had the significant sterol content (fucosterol, 21.76±0.1 μg/g). Green algae, C. bursa and H. tuna, showed the highest level of sterols (β‐sitosterol, 95.21±0.16 μg/g and 73.90±0.08 μg/g, respectively). H. tuna had the highest content of calcium (Ca) in amount of 55125 μg/g. In C. bursa, C. barbata and C. nodosa, the Na/K ratio was low (0.43, 0.46 and 0.69, respectively). 相似文献
935.
Tatjana Kleine Thomas Nägele H. Ekkehard Neuhaus Christian Schmitz-Linneweber Alisdair R. Fernie Peter Geigenberger Bernhard Grimm Kerstin Kaufmann Edda Klipp Jörg Meurer Torsten Möhlmann Timo Mühlhaus Belen Naranjo Jörg Nickelsen Andreas Richter Hannes Ruwe Michael Schroda Serena Schwenkert Oliver Trentmann Felix Willmund Reimo Zoschke Dario Leister 《The Plant journal : for cell and molecular biology》2021,106(1):23-40
Acclimation is the capacity to adapt to environmental changes within the lifetime of an individual. This ability allows plants to cope with the continuous variation in ambient conditions to which they are exposed as sessile organisms. Because environmental changes and extremes are becoming even more pronounced due to the current period of climate change, enhancing the efficacy of plant acclimation is a promising strategy for mitigating the consequences of global warming on crop yields. At the cellular level, the chloroplast plays a central role in many acclimation responses, acting both as a sensor of environmental change and as a target of cellular acclimation responses. In this Perspective article, we outline the activities of the Green Hub consortium funded by the German Science Foundation. The main aim of this research collaboration is to understand and strategically modify the cellular networks that mediate plant acclimation to adverse environments, employing Arabidopsis, tobacco (Nicotiana tabacum) and Chlamydomonas as model organisms. These efforts will contribute to ‘smart breeding’ methods designed to create crop plants with improved acclimation properties. To this end, the model oilseed crop Camelina sativa is being used to test modulators of acclimation for their potential to enhance crop yield under adverse environmental conditions. Here we highlight the current state of research on the role of gene expression, metabolism and signalling in acclimation, with a focus on chloroplast-related processes. In addition, further approaches to uncovering acclimation mechanisms derived from systems and computational biology, as well as adaptive laboratory evolution with photosynthetic microbes, are highlighted. 相似文献
936.
Kim Wiskott Federica Gilardi Alexandre Hainard Jean-Charles Sanchez Aurelien Thomas Tatjana Sajic Tony Fracasso 《Proteomics》2023,23(3-4):2200078
Abusive head trauma (AHT) is a leading cause of mortality and morbidity in infants. While the reported incidence is close to 40 cases per 100′000 births/year, misdiagnoses are commonly observed in cases with atypical, subacute, or chronic presentation. Currently, standard clinical evaluation of inflicted intracranial hemorrhagic injury (ICH) in infants urgently requires a screening test able to identify infants who need additional investigations. Blood biomarkers characteristic of AHT may assist in detecting these infants, improving prognosis through early medical care. To date, the application of innovative omics technologies in retrospective studies of AHT in infants is rare, due also to the blood serum and cerebrospinal fluid of AHT cases being scarce and not systematically accessible. Here, we explored the circulating blood proteomes of infants with severe AHT and their atraumatic controls. We discovered 165 circulating serum proteins that display differential changes in AHT cases compared with atraumatic controls. The peripheral blood proteomes of pediatric AHT commonly reflect: (i) potentially secreted proteome from injured brain, and (ii) proteome dysregulated in the system's circulation by successive biological events following acute ICH. This study opens up a novel opportunity for research efforts in clinical screening of AHT cases. 相似文献
937.
Nada Stankovic Lidija Senerovic Tatjana Ilic-Tomic Branka Vasiljevic Jasmina Nikodinovic-Runic 《Applied microbiology and biotechnology》2014,98(9):3841-3858
The growing demand to fulfill the needs of present-day medicine in terms of novel effective molecules has lead to reexamining some of the old and known bacterial secondary metabolites. Bacterial prodigiosins (prodiginines) have a long history of being re markable multipurpose compounds, best examined for their anticancer and antimalarial activities. Production of prodigiosin in the most common producer strain Serratia marcescens has been described in great detail. However, few reports have discussed the ecophysiological roles of these molecules in the producing strains, as well as their antibiotic and UV-protective properties. This review describes recent advances in the production process, biosynthesis, properties, and applications of bacterial prodigiosins. Special emphasis is put on undecylprodigiosin which has generally been a less studied member of the prodigiosin family. In addition, it has been suggested that proteins involved in undecylprodigiosin synthesis, RedG and RedH, could be a useful addition to the biocatalytic toolbox being able to mediate regio- and stereoselective oxidative cyclization. Judging by the number of recent references (216 for the 2007–2013 period), it has become clear that undecylprodigiosin and other bacterial prodigiosins still hold surprises in terms of valuable properties and applicative potential to medical and other industrial fields and that they still deserve continuing research curiosity. 相似文献
938.
939.
940.
Jana Harichová Edita Karelová Katarína Chovanová Tatjana Stojnev Miloslava Prokšová Ján Brindza Peter Brindza Dezider Tóth Domenico Pangallo Peter Ferianc 《Biologia》2006,61(6):663-670
This research work was oriented to outlining the diversity of Gram-negative culturable portion of the bacterial community
in three fruit plants rhizosphere. Rhizosphere samples were taken from European chestnut (Castanea sativa Mill), true service tree (Sorbus domestica L.) and cornelian cherry (Cornus mas L.) plants. Experiments were conducted for three years during the vegetation period, and the bacterial community structure
was assessed with cultivation-dependent approach. Many Gram-negative isolates (n = 251) from the rhizosphere survived sub culturing and were identified by biochemical tests. A total of 57 species belonging
to 29 genera were identified and assigned to four broad taxonomic groups (Bacteroidetes, Alpha-, Beta- and Gamma-proteobacteria). Several specific bacterial cluster communities were identified inside all the three rhizospheres. Most of the species belonged
to the genera Moraxella, Pseudomonas, Pantoea, Enterobacter and Acinetobacter. In addition, while, using the plate count analysis, large discrepancies in numbers among physiological groups of bacteria
cultured from three rhizosphere samples have not been revealed, more expressive distinctions among bacterial populations were
obtained concerning the relative abundance of different genera, different taxonomic groups as well as different diversity
indices. Furthermore, the number of cultured bacteria and their taxonomic distribution in the rhizosphere of all three plants
changed not only explicitly during vegetation period but continually during the three years of investigation. It seems that
rhizosphere bacterial populations of each plant are under the influence of the specific root-released materials. 相似文献