250 research outputs found
Differential fates of Emiliania huxleyi-derived fatty acids and alkenones in coastal marine sediments: Effects of the benthic crustacean Palaemonetes pugio
In order to examine how benthic crustaceans affect the fates of phytoplankton-derived lipid biomarkers (fatty acids and alkenones) in coastal marine sediments, we incubated Emiliania huxleyi cells in microcosms (pre-sieved sediment cores with and without the grass shrimp Palaemonetes pugio ) over six weeks. Crustacean, transport of surface sediments, and distributions of algal lipids were followed during incubations. Crustacean activities enhanced degradation of algal fatty acids (2–4× faster) but had a small impact on algal alkenone degradation (\u3c1.4×) compared to the controls. During the first few days of incubations, alkenone concentrations were enriched while algal fatty acid concentrations were depleted in suspended particles in the overlying water of cores, indicating that P. pugio selectively grazed algal material from sediments and preferentially assimilated fatty acids over alkenones through digestion. Unlike algal fatty acids, alkenones were degraded primarily by microbial processes rather than by crustacean grazing. A substantial fraction (20–30%) of algal lipids was moved downward to the subsurface of sediments by P. pugio but algal fatty acids were more rapidly (3–6×) degraded than alkenones. In the presence of P. pugio, fatty acids bound in cell membrane and intracellular storage components degraded similarly, indicating that the crustacean activities minimized the effects of structural associations on fatty acid decomposition. Furthermore, there was no preferential degradation of 37:3 and 37:2 alkenones in both crustacean and control cores, suggesting that the U37k\u27 index (a paleotemperature indicator) was not significantly altered by P. pugio\u27s grazing or microbial decomposition
Film formation and surface renewal on a rotating spoked disk for polymer devolatilization
The financial supports from the National Natural Science Foundation of China (No.21676007) are gratefully acknowledged.Peer reviewedPostprin
Self-blindable Credential: Towards LightWeight Anonymous Entity Authentication
We are witnessing the rapid expansion of smart devices in our daily
life. The need for individual privacy protection calls for anonymous
entity authentication techniques with affordable efficiency upon the
resource-constrained smart devices. Towards this objective, in this
paper we propose self-blindable credential, a lightweight
anonymous entity authentication primitive. We provide a formulation
of the primitive and present two concrete instantiations. The first
scheme implements verifier-local revocation and the second scheme
enhances the former with forward security. Our analytical
performance results show that our schemes outperform relevant
existing schemes
A Systematic Study of Dysregulated MicroRNA in Type 2 Diabetes Mellitus.
MicroRNAs (miRNAs) are small noncoding RNAs that modulate the cellular transcriptome at the post-transcriptional level. miRNA plays important roles in different disease manifestation, including type 2 diabetes mellitus (T2DM). Many studies have characterized the changes of miRNAs in T2DM, a complex systematic disease; however, few studies have integrated these findings and explored the functional effects of the dysregulated miRNAs identified. To investigate the involvement of miRNAs in T2DM, we obtained and analyzed all relevant studies published prior to 18 October 2016 from various literature databases. From 59 independent studies that met the inclusion criteria, we identified 158 dysregulated miRNAs in seven different major sample types. To understand the functional impact of these deregulated miRNAs, we performed targets prediction and pathway enrichment analysis. Results from our analysis suggested that the altered miRNAs are involved in the core processes associated with T2DM, such as carbohydrate and lipid metabolisms, insulin signaling pathway and the adipocytokine signaling pathway. This systematic survey of dysregulated miRNAs provides molecular insights on the effect of deregulated miRNAs in different tissues during the development of diabetes. Some of these miRNAs and their mRNA targets may have diagnostic and/or therapeutic utilities in T2DM
Self-blindable credential: Towards anonymous entity authentication upon resource-constrained devices
Algal blooms: how are they harming models used for climate management?
18th International Conference on Harmful Algae (ICHA 2018), 21-26 October 2018, Nantes, France.-- 4 pages, 2 figuresMicroalgae blooms are generally associated with bacterial secondary producers. They produce organic matter (OM), some of which associates with the sea surface microlayer (SML). OM in the SML below the actual surface reduces fluxes of energy, including heat and momentum, and substances, including greenhouse gases, aerosols, algae, bacteria and viruses. In addition to the SML-associated OM, another OM fraction, foam (including whitecaps), often lies above the primary SML when windspeeds exceed about 5 m s-1, trapping gas bubbles. Such foam also dramatically increases albedo, reflecting solar radiation back into space, thus reducing solar heating and penetration of photosynthetically active radiation. Mean coverage of the ocean surface by foam has been measured to range between 1-6%, particularly in zones of Trade Winds. Different types of OM, and particularly their mechanical properties, depend on ambient algal abundance, as well as on taxonomic composition, as do the dynamics of foam formation and decay. Air-sea fluxes may thus be influenced by genomic control through the blooming microalgae and Darwinian-type evolution. Bacteria may also play a role. In addition, foam patches on the ocean’s surface serve as a unique microbial habitat. Such blooms, particularly when their taxonomic composition changes unpredictably, are likely to be harming the usefulness of climate models. Some of this harm might be mitigated by studying the relevant effects of these blooms on fluxes, and incorporating these effects into climate modelsJS is supported by National Nature Science Foundation of China grant (41876134) and the Changjiang Scholar Program of Chinese Ministry of Educatio
The energy spectrum of all-particle cosmic rays around the knee region observed with the Tibet-III air-shower array
We have already reported the first result on the all-particle spectrum around
the knee region based on data from 2000 November to 2001 October observed by
the Tibet-III air-shower array. In this paper, we present an updated result
using data set collected in the period from 2000 November through 2004 October
in a wide range over 3 decades between eV and eV, in which
the position of the knee is clearly seen at around 4 PeV. The spectral index is
-2.68 0.02(stat.) below 1PeV, while it is -3.12 0.01(stat.) above 4
PeV in the case of QGSJET+HD model, and various systematic errors are under
study now.Comment: 12 pages, 7 figures, accepted by Advances in space researc
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