Impacts of elevated atmospheric ozone on peatland below-ground DOC characteristics

Rising concentrations of tropospheric ozone are having detrimental impacts on the growth of crop and forest species and some studies have reported inhibition of the allocation of carbon below ground. The effects of ozone on peatland ecosystems have received relatively little attention, despite their importance within the global carbon cycle. During this study, cores from a Welsh minerotrophic fen and ombrotrophic bog were exposed to four ambient/ elevated ozone concentration regimes representing current and predicted 2050 profiles. A large and significant reduction in the concentration of porewater dissolved organic carbon (DOC) was recorded in the fen cores exposed to the elevated ozone concentrations (up to −55%), with a concurrent shift to a higher molecularweight of the remaining soil carbon. No effects of ozone on DOC concentrations or characteristics were recorded for the bog cores. The data suggest higher ozone sensitivity of plants growing in the fen-type peatland, that the impacts on the vegetation may affect soil carbon characteristics through a reduction in root exudates and that theremay have been a shift in the source of substrate DOC for microbial consumption from vegetation exudates to native soil carbon. Theremay also have been a direct effect of ozone molecules reacting with soil organic matter after being transported into the soil through the aerenchyma tissue of the overlying vegetation. These qualitative changes in the soil carbon in response to elevated ozone may have important implications for carbon cycling in peatland ecosystems, and therefore climate change

Flexible Neural Electrode Array Based-on Porous Graphene for Cortical Microstimulation and Sensing.

Neural sensing and stimulation have been the backbone of neuroscience research, brain-machine interfaces and clinical neuromodulation therapies for decades. To-date, most of the neural stimulation systems have relied on sharp metal microelectrodes with poor electrochemical properties that induce extensive damage to the tissue and significantly degrade the long-term stability of implantable systems. Here, we demonstrate a flexible cortical microelectrode array based on porous graphene, which is capable of efficient electrophysiological sensing and stimulation from the brain surface, without penetrating into the tissue. Porous graphene electrodes show superior impedance and charge injection characteristics making them ideal for high efficiency cortical sensing and stimulation. They exhibit no physical delamination or degradation even after 1 million biphasic stimulation cycles, confirming high endurance. In in vivo experiments with rodents, same array is used to sense brain activity patterns with high spatio-temporal resolution and to control leg muscles with high-precision electrical stimulation from the cortical surface. Flexible porous graphene array offers a minimally invasive but high efficiency neuromodulation scheme with potential applications in cortical mapping, brain-computer interfaces, treatment of neurological disorders, where high resolution and simultaneous recording and stimulation of neural activity are crucial

Comparative profiling of the transcriptional response to infection in two species of Drosophila by short-read cDNA sequencing

<p>Abstract</p> <p>Background</p> <p>Homology-based comparisons of the genes involved in innate immunity across many insect taxa with fully sequenced genomes has revealed a striking pattern of gene gain and loss, particularly among genes that encode proteins involved in clearing pathogens (effectors). However, limited functional annotation in non-model systems has hindered understanding of evolutionary novelties in the insect innate immune system.</p> <p>Results</p> <p>We use short read sequencing technology (Illumina/Solexa) to compare the transcriptional response to infection between the well studied model system <it>Drosophila melanogaster </it>and the distantly related drosophilid <it>D. virilis</it>. We first demonstrate that Illumina/Solexa sequencing of cDNA from infected and uninfected <it>D. melanogaster </it>recapitulates previously published microarray studies of the transcriptional response to infection in this species, validating our approach. We then show that patterns of transcription of homologous genes differ considerably between <it>D. melanogaster </it>and <it>D. virilis</it>, and identify potential candidates for novel components of the <it>D. virilis </it>immune system based on transcriptional data. Finally, we use a proteomic approach to characterize the protein constituents of the <it>D. virilis </it>hemolymph and validate our transcriptional data.</p> <p>Conclusion</p> <p>These results suggest that the acquisition of novel components of the immune system, and particularly novel effector proteins, may be a common evolutionary phenomenon.</p

Formal total synthesis of (±)-conduramine E utilising the Bryce-Smith-Gilbert photoamination reaction

Utilising a Bryce-Smith-Gilbert photoamination of benzene as a key step, a synthesis of ()-conduramine E was carried out. A highly regioselective dihydroxylation of a cyclic diene was effected utilising Sharpless AD-mix-b

Allying For Peace: Treaty Obligations and Conflict Between Allies

We argue that certain provisions of alliance treaties can signal credible commitments to a peaceful relationship among members and establish institutional mechanisms that promote the settlement of disagreements through peaceful negotiation. Nonaggression, peaceful dispute settlement, military institutionalization, and permanent organization provisions should increase the duration of peace between alliance members; we test our hypotheses with a duration model. The analysis generally supports our expectations except that alliances that create permanent organizations, even those specifically established to arbitrate disagreements, are associated with shorter durations of peace. We conclude with some implications of our argument for the study of military alliances and international institutions more broadly

Entanglement-free certification of entangling gates

Not all quantum protocols require entanglement to outperform their classical alternatives. The nonclassical correlations that lead to this quantum advantage are conjectured to be captured by quantum discord. Here we demonstrate that discord can be explicitly used as a resource: certifying untrusted entangling gates without generating entanglement at any stage. We implement our protocol in the single-photon regime, and show its success in the presence of high levels of noise and imperfect gate operations. Our technique offers a practical method for benchmarking entangling gates in physical architectures in which only highly-mixed states are available.Comment: 5 pages, 2 figure

CONCENTRATION ISSUES IN THE U.S. BEEF SUBSECTOR

Industrial Organization, Livestock Production/Industries,