Untargeted metabolomic profiling of Sphagnum fallax reveals novel antimicrobial metabolites

Sphagnum mosses dominate peatlands by employing harsh ecosystem tactics to prevent vascular plant growth and microbial degradation of these large carbon stores. Knowledge about Sphagnum-produced metabolites, their structure and their function, is important to better understand the mechanisms, underlying this carbon sequestration phenomenon in the face of climate variability. It is currently unclear which compounds are responsible for inhibition of organic matter decomposition and the mechanisms by which this inhibition occurs. Metabolite profiling of Sphagnum fallax was performed using two types of mass spectrometry (MS) systems and 1H nuclear magnetic resonance spectroscopy (1H NMR). Lipidome profiling was performed using LC-MS/MS. A total of 655 metabolites, including one hundred fifty-two lipids, were detected by NMR and LC-MS/MS-329 of which were novel metabolites (31 unknown lipids). Sphagum fallax metabolite profile was composed mainly of acid-like and flavonoid glycoside compounds, that could be acting as potent antimicrobial compounds, allowing Sphagnum to control its environment. Sphagnum fallax metabolite composition comparison against previously known antimicrobial plant metabolites confirmed this trend, with seventeen antimicrobial compounds discovered to be present in Sphagnum fallax, the majority of which were acids and glycosides. Biological activity of these compounds needs to be further tested to confirm antimicrobial qualities. Three fungal metabolites were identified providing insights into fungal colonization that may benefit Sphagnum. Characterizing the metabolite profile of Sphagnum fallax provided a baseline to understand the mechanisms in which Sphagnum fallax acts on its environment, its relation to carbon sequestration in peatlands, and provide key biomarkers to predict peatland C store changes (sequestration, emissions) as climate shifts.Microbiomes in Transition; Office of Biological and Environmental ResearchOpen access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Time- and momentum-resolved photoemission studies using time-of-flight momentum microscopy at a free-electron laser

Time-resolved photoemission with ultrafast pump and probe pulses is an emerging technique with wide application potential. Real-time recording of nonequilibrium electronic processes, transient states in chemical reactions, or the interplay of electronic and structural dynamics offers fascinating opportunities for future research. Combining valence-band and core-level spectroscopy with photoelectron diffraction for electronic, chemical, and structural analyses requires few 10 fs soft X-ray pulses with some 10 meV spectral resolution, which are currently available at high repetition rate free-electron lasers. We have constructed and optimized a versatile setup commissioned at FLASH/PG2 that combines free-electron laser capabilities together with a multidimensional recording scheme for photoemission studies. We use a full-field imaging momentum microscope with time-of-flight energy recording as the detector for mapping of 3D band structures in (kx, ky, E) parameter space with unprecedented efficiency. Our instrument can image full surface Brillouin zones with up to 7 Å−1 diameter in a binding-energy range of several eV, resolving about 2.5 × 105 data voxels simultaneously. Using the ultrafast excited state dynamics in the van der Waals semiconductor WSe2 measured at photon energies of 36.5 eV and 109.5 eV, we demonstrate an experimental energy resolution of 130 meV, a momentum resolution of 0.06 Å−1, and a system response function of 150 fs

RRS Discovery Cruise D321b, Reykjavik to Clyde via Rockall, Scotland and the Wyville Thomson Ridge, 24 August to 9 September

A joint SAMS / NOCS cruise led by the Scottish Association for Marine Scienc

Techno-economic evaluation of narrowband and broadband access network alternatives and evolution scenario assessment

The paper presents the main results obtained within the Research in Advanced Communications in Europe (RACE) project: 2087 TITAN (Tool for Introduction Scenarios and Techno-Economic Evaluation of The Access Network) regarding minimum-risk introductory routes for new narrowband and broadband services in the residential and small business market. The project developed a methodology and a tool for technoeconomic evaluation of advanced narrowband and broadband telecommunications networks and services. Results from four extensive access network studies are presented. For the narrowband services, optical access and radio in the local loop have been assessed and compared to conventional copper layout in a greenfield environment. Access network upgrade strategies for emerging new broadband services have been evaluated in three studies, with technological options ranging from enhanced copper to hybrid-fiber-coax (HFC) and broadband passive optical networks. An extensive study on different broadband access network upgrade alternatives for public network operators (PNO's) were carried out, taking into account the diversity of conditions met today by European countries. In another study, the effect of competition in the access network was modeled assuming two main operators sharing the market. Broadband upgrade alternatives were evaluated for a new cable operator, competing with the dominant public network operator. In addition, video-on-demand (VoD) and Internet access upgrades have been analyzed. The paper demonstrates the viability of techno-economic studies for the access network, including in-depth analysis of the time-dependence of component cost, tariffs, service-penetrations and market shares. This work intends to support establishing guidelines for strategic decisions regarding the development of the access network alternatives of different operators