The effects of soil eutrophication propagate to higher trophic levels

Conservation Biolog

Diversity of the active methanotrophic community in acidic peatlands as assessed by mRNA and SIP-PLFA analyses

The active methanotroph community was investigated for the first time in heather (Calluna)-covered moorlands and Sphagnum/Eriophorum-covered UK peatlands. Direct extraction of mRNA from these soils facilitated detection of expression of methane monooxygenase genes, which revealed that particulate methane monooxygenase and not soluble methane monooxygenase was probably responsible for CH4 oxidation in situ, because only pmoA transcripts (encoding a subunit of particulate methane monooxygenase) were readily detectable. Differences in methanotroph community structures were observed between the Calluna-covered moorland and Sphagnum/Eriophorum-covered gully habitats. As with many other Sphagnum-covered peatlands, the Sphagnum/Eriophorum-covered gullies were dominated by Methylocystis. Methylocella and Methylocapsa-related species were also present. Methylobacter-related species were found as demonstrated by the use of a pmoA-based diagnostic microarray. In Calluna-covered moorlands, in addition to Methylocella and Methylocystis, a unique group of peat-associated type I methanotrophs (Gammaproteobacteria) and a group of uncultivated type II methanotrophs (Alphaproteobacteria) were also found. The pmoA sequences of the latter were only distantly related to Methylocapsa and also to the RA-14 group of methanotrophs, which are believed to be involved in oxidation of atmospheric concentrations of CH4. Soil samples were also labelled with (CH4)-C-13, and subsequent analysis of the C-13-labelled phospholipid fatty acids (PLFAs) showed that 16:1 omega 7, 18:1 omega 7 and 18:1 omega 9 were the major labelled PLFAs. The presence of C-13-labelled 18:1 omega 9, which was not a major PLFA of any extant methanotrophs, indicated the presence of novel methanotrophs in this peatland

Neuropsychological Assessment Using Virtual Environments: Enhanced Assessment Technology for Improved Ecological Validity

Abstract. Although today’s neuropsychological assessment procedures are widely used, neuropsychologists have been slow to embrace technological advancements. Two essential limitations have resulted from this refusal of techno-logical adaptation: First, current neuropsychological assessment procedures repre-sent a technology that has barely changed since the first scales were developed in the early 1900s. Second, while the historical purpose of clinical neuropsychology was differential diagnosis of brain pathology, technological advances in other clinical neurosciences have changed the neuropsychologist’s role to that of mak-ing ecologically valid predictions about the impact of a given patient’s neurocog-nitive abilities and disabilities on everyday functioning. After a brief discussion of current applications of computer-based neuropsychological assessment, there is a discussion of an increasingly important topic in recent decades—the design of ecologically valid neuropsychological instruments to address real world out-comes. Finally, there is an exploration of virtual reality environments for ecologi-cally valid neuropsychological assessments that make use of current technological advances. It is concluded that a future possible virtual reality-based neuropsy-chological assessment battery will combine the control and rigor of technologi-cally advanced computerized laboratory measures, the psychometric rigor (i.e., veridicality) of traditional paper-and-pencil assessments, and verisimilitude ap-proximating real life situations.

Multi-messenger Observations of a Binary Neutron Star Merger

International audienceOn 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of $\sim 1.7\,{\rm{s}}$ with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg(2) at a luminosity distance of ${40}_{-8}^{+8}$ Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 $\,{M}_{\odot }$. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at $\sim 40\,{\rm{Mpc}}$) less than 11 hours after the merger by the One-Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ∼10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position $\sim 9$ and $\sim 16$ days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC 4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta