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971.
Bats play an important role in agroecology and are effective bioindicators of environmental conditions, but little is known about their fundamental migration ecology, much less how these systems are responding to global change. Some of the world's largest bat populations occur during the summer in the south‐central United States, when millions of pregnant females migrate from lower latitudes to give birth in communal maternity colonies. Despite a relatively large volume of research into these colonies, many fundamental questions regarding their abundance—including their intra‐ and interseasonal variability—remain unanswered, and even estimating the size of individual populations has been a long‐running challenge. Overall, monitoring these bat populations at high temporal resolution (e.g., nightly) and across long time spans (e.g., decades) has been impossible. Here, we show 22 continuous years of nightly population counts at Bracken Cave, a large bat colony in south‐central Texas, enabling the first climate‐scale phenological analysis. Using quantitative radar monitoring, we found that spring migration and the summer reproductive cycle have advanced by approximately 2 weeks over the study period. Furthermore, we quantify the ongoing growth of a newly—established overwintering population that indicates a system‐wide response to changing environmental conditions. Our observations reveal behavioral plasticity in bats’ ability to adapt to changing resource availability, and provide the first long‐term quantification of their response to a changing climate. As aerial insectivores, these changes in bat phenology and propensity for overwintering indicate probable shifts in prey availability, with clear implications for pest management across wider regional agrisystems. 相似文献
972.
Anne-Sophie Mathieu Charlotte Tinel Hélène Dailly Muriel Quinet Stanley Lutts 《Plant and Soil》2018,424(1-2):273-288
Aims
Dianthus caryophyllus is a commercially important ornamental flower. Plant growth promoting rhizobacteria are increasingly applied as bio-fertilisers and bio-fortifiers. We studied the effect of a rhizospheric isolate Klebsiella SGM 81 strain to promote D. caryophyllus growth under sterile and non-sterile conditions, to colonise its root system endophytically and its impact on the cultivatable microbial community. We identified the auxin indole-3-acetic acid (IAA) production of Klebsiella SGM 81 as major bacterial trait most likely to enhance growth of D. caryophyllus.Methods
ipdC dependent IAA production of SGM 81 was quantified using LC-MS/MS and localised proximal to D. caryophyllus roots and correlated to root growth promotion and characteristic morphological changes. SGM 81 cells were localised on and within the plant root using 3D rendering confocal microscopy of gfp expressing SGM 81. Using Salkowski reagent IAA production was quantified and localised proximal to roots in situ. The effect of different bacterial titres on rhizosphere bacterial population was CFU enumerated on nutrient agar. The genome sequence of Klebsiella SGM 81 (accession number PRJEB21197) was determined to validate PGP traits and phylogenic relationships.Results
Inoculation of D. caryophyllus roots with Klebsiella SGM 81 drastically promoted plant growth when grown in agar and soil, concomitant with a burst in root hair formation, suggesting an increase in root auxin activity. We sequenced the Klebsiella SGM 81 genome, identified the presence of a canonical ipdC gene in Klebsiella SGM 81, confirmed bacterial production and secretion of IAA in batch culture using LC-MS/MS and localised plant dependent IAA production by SGM 81 proximal to roots. We found Klebsiella SGM 81 to be a rhizoplane and endophytic coloniser of D. caryophyllus roots in a dose dependent manner. We found no adverse effects of SGM 81 on the overall rhizospheric microbial population unless supplied to soil in very high titres.Conclusion
Klebsiella SGM 81 effectively improves root traits of D. caryophyllus in a dose dependent manner, likely through tryptophan dependent IAA production in the rhizoplane and potentially within the intercellular spaces of root tissue. Under optimal plant growth promoting conditions in non-sterile soil, the high total microbial titre in the rhizosphere supports a mutualistic relationship between Klebsiella SGM 81 and carnation that potentially extends to the wider rhizosphere microbiota.973.
Louise R. Peckre Charlotte Defolie Peter M. Kappeler Claudia Fichtel 《Primates; journal of primatology》2018,59(5):483-494
Self-anointing, referring to the behaviour of rubbing a material object or foreign substance over different parts of the body, has been observed in several vertebrate species, including primates. Several functions, such as detoxifying a rich food source, social communication and protection against ectoparasites, have been proposed to explain this behaviour. Here, we report observations of six wild red-fronted lemurs (Eulemur rufifrons) of both sexes and different age classes anointing their perianal-genital areas and tails with chewed millipedes. Several individuals also ingested millipedes after prolonged chewing. In light of the features of the observed interactions with millipedes, and the nature and potential metabolic pathways of the released chemicals, we suggest a potential self-medicative function. Specifically, we propose that anointing combined with the ingestion of millipedes’ benzoquinone secretions by red-fronted lemurs may act in a complementary fashion against gastrointestinal parasite infections, and more specifically Oxyuridae nematodes, providing both prophylactic and therapeutic effects. 相似文献
974.
Charlotte Victoria Eley Vicki Louise Young Beverley Ann Hoekstra 《Journal of biological education》2018,52(2):166-173
Introduction: e-Bug is an international educational resource for young people covering microbes, hygiene and antibiotics. e-Bug supports NICE guidance on changing public behaviour around antibiotic use. This study aimed to determine educators’ views of the e-Bug teacher resources to inform further development and dissemination of e-Bug. Methods: Age appropriate e-Bug resource packs were posted to every primary school (N = 19,142) and secondary school (N = 5637) in England with a cover letter signed by the Chief Medical Officer, Chief Executive of PHE and e-Bug Project Lead inviting educators to complete an online survey to evaluate the e-Bug resources. The online survey consisted of nine questions and took approximately 15 min to complete. Results: 695 participants completed the online survey. 94% of participants rated the e-Bug resource as excellent or good; one fifth of respondents used the e-Bug resources at least termly. Educators who used e-Bug rated the different lesson plans as excellent or good including ‘Introduction to Microbes’ (98%) and ‘Hand Hygiene’ (95%). Educators provided suggestions for the development of additional lessons plans. Conclusions: Educators view e-Bug as a valuable resource for teaching children about hygiene and antibiotics. Further e-Bug promotion and resource development is required to increase awareness and usage in schools. 相似文献
975.
976.
Paolo Ruzza Rosa Maria Vitale Rohanah Hussain Alessia Montini Claudia Honisch Alice Pozzebon Charlotte S. Hughes Barbara Biondi Pietro Amodeo GianPietro Sechi Giuliano Siligardi 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(6):1317-1326
Background
Lysozyme is a widely distributed enzyme present in a variety of tissue and body fluids. Human and hen egg white lysozyme are used as validated model to study protein folding and stability and to understand protein misfolding and aggregation. We recently found that ceftriaxone, a β-lactam antibiotic able to overcome the blood-brain barrier, successfully eliminated the cellular toxic effects of misfolded proteins as Glial Fibrillary Acidic Protein (GFAP) and α-synuclein. To further understand the anti-amyloidogenic properties of ceftriaxone, we studied its activity towards lysozyme aggregation with the aim to investigate a possible chaperone-like activity of this molecule.Methods
Here we present the results obtained from fluorescence and synchrotron radiation circular dichroism spectroscopies and from molecular docking and molecular dynamics about the lysozyme-ceftriaxone interaction at neutral and acidic pH values.Results
We found that ceftriaxone exhibits comparable affinity constants to lysozyme in both experimental pH conditions and that its addition enhanced lysozyme stability reducing its aggregation propensity in acidic conditions. Computational methods allowed the identification of the putative binding site of ceftriaxone, thus rationalizing the spectroscopic results.Conclusions
Spectroscopy data and molecular dynamics indicated a protective effect of ceftriaxone on pathological aggregation phenomena suggesting a chaperone-like effect of this molecule on protein folding.General significanceThese results, in addition to our previous studies on α-synuclein and GFAP, confirm the property of ceftriaxone to inhibit the pathological protein aggregation of lysozyme also by a chaperone-like mechanism, extending the potential therapeutic application of this molecule to some forms of human hereditary systemic amyloidosis. 相似文献977.
Influence of pH and redox on mobilization of inositol hexakisphosphate from oligotrophic lake sediment 总被引:1,自引:0,他引:1
Kasper Reitzel Henning S. Jensen Benjamin L. Turner Charlotte Jørgensen 《Biogeochemistry》2018,140(1):15-30
It has been suggested that inositol hexakisphosphate (IP6) contributes to the release of phosphorus (P) from lake sediments, but a mechanistic understanding remains elusive. We investigated the potential mobilization and mineralization of myo- and scyllo-IP6 from the sediment of an oligotrophic Danish lake known to contain high concentrations of inositol phosphates. Solution 31P NMR spectroscopy was used to determine changes in myo- and scyllo-IP6 in laboratory microcosms incubated under either oxic or anoxic conditions. In addition, we incubated sediment slurries adjusted to pH between 4.9 and 6.6, with and without addition of myo-IP6, and induced redox changes by adding starch and sulfate. We observed no significant changes in myo- or scyllo-IP6 after 1 year of incubation under anaerobic conditions. A sequential extraction procedure revealed that one half of the added myo-IP6 was recovered in the humic acid fraction (acid-insoluble organic matter) and the other half in the fulvic acid fraction (acid-soluble organic matter). Reduction in redox potential by starch addition did not mobilize myo-IP6, but myo-IP6 bound to humic acids was released to the pore water when the pH was increased to ≥?5.8. This pH-induced mobilization of IP6 occurred in parallel with increases in dissolved iron and organic matter, suggesting the release of IP6 bound to humic acids through metal bridges. We conclude that myo-IP6 mobilization from this oligotrophic lake sediment is driven by changes in pH rather than by changes in the redox potential. 相似文献
978.
979.
Platycarpum vriesendorpiae sp. nov., a second new species of Tribe Henriquezieae (Rubiaceae) from nutrient‐poor soils in the Peruvian Amazon
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The new species Platycarpum vriesendorpiae N. Dávila (Rubiaceae, Henriquezieae) is described from Peru, where it is restricted to white‐sand forests and peatlands in the Tapiche and Blanco River watersheds in southeastern Loreto Region. The new species is generally similar to P. acreanum Rogers of western Brazil in its phyllotaxy, leaf pubescence, and fruit shape and size. However, P. vriesendorpiae differs in its triangular stipules that are 2‐ or 3‐angled at the base and in its smaller corolla. 相似文献