2,418 research outputs found
The Role of Malic Enzyme on Promoting Total Lipid and Fatty Acid Production in Phaeodactylum tricornutum
To verify the function of malic enzyme (ME1), the ME1 gene was endogenously overexpressed in Phaeodactylum tricornutum. Overexpression of ME1 increased neutral and total lipid content and significantly increased saturated fatty acids (SFAs) and polyunsaturated fatty acids (PUFAs) in transformants, which varied between 23.19 and 25.32% in SFAs and between 49.02 and 54.04% in PUFAs, respectively. Additionally, increased ME1 activity was accompanied by elevated NADPH content in all three transformants, indicating that increased ME1 activity produced additional NADPH comparing with that of WT. These results indicated that ME1 activity is NADP-dependent and plays an important role in the NADPH levels required for lipid synthesis and fatty acid desaturation in P. tricornutum. Furthermore, our findings suggested that overexpression of endogenous ME1 represents a valid method for boosting neutral-lipid yield in diatom
Nodal degeneracy of guided modes in uniaxial crystal slabs
We study the dispersions of the guided modes in the continuous uniaxial crystal slab waveguide and engineer their degeneracies through dielectric anisotropy. By switching the uniaxial positivity and negativity, we can obtain distinctive nodal types, point and line, for the lowest degeneracy in frequency. The mirror symmetry protections, Mx and My, are pointed out, and the degeneracy properties are intuitively analyzed through comparing the approximate slopes of the guided modes. Our results reveal a link between the lowest nodal types and the positivity/negativity of the uniaxial crystal, and provide a new approach to regulate the topology of degeneracy in two-dimensional photonic bands
The LEGUE Input Catalogue for Dark Night Observing in the LAMOST Pilot Survey
We outline the design of the dark nights portion of the LAMOST Pilot Survey,
which began observations in October 2011. In particular, we focus on Milky Way
stellar candidates that are targeted for the LEGUE (LAMOST Experiment for
Galactic Understanding and Exploration) survey. We discuss the regions of sky
in which spectroscopic candidates were selected, and the motivations for
selecting each of these sky areas. Some limitations due to the unique design of
the telescope are discussed, including the requirement that a bright (V < 8)
star be placed at the center of each plate for wavefront sensing and active
optics corrections. The target selection categories and scientific goals
motivating them are briefly discussed, followed by a detailed overview of how
these selection functions were realized. We illustrate the difference between
the overall input catalog - Sloan Digital Sky Survey (SDSS) photometry - and
the final targets selected for LAMOST observation.Comment: 11 pages, 7 figures, accepted for publication in RA
Immunologic Changes during Pandemic (H1N1) 2009, China
We analyzed changes in immunologic values over time for 28 hospitalized patients with pandemic (H1N1) 2009. Levels of interleukin-6, interferon-γ, and interleukin-10 increased 1 day after illness onset and then decreased to baseline levels. Levels of virus-specific antibody were undetectable 1 day after illness onset and peaked 36 days later
An Algorithm for Preferential Selection of Spectroscopic Targets in LEGUE
We describe a general target selection algorithm that is applicable to any
survey in which the number of available candidates is much larger than the
number of objects to be observed. This routine aims to achieve a balance
between a smoothly-varying, well-understood selection function and the desire
to preferentially select certain types of targets. Some target-selection
examples are shown that illustrate different possibilities of emphasis
functions. Although it is generally applicable, the algorithm was developed
specifically for the LAMOST Experiment for Galactic Understanding and
Exploration (LEGUE) survey that will be carried out using the Chinese Guo Shou
Jing Telescope. In particular, this algorithm was designed for the portion of
LEGUE targeting the Galactic halo, in which we attempt to balance a variety of
science goals that require stars at fainter magnitudes than can be completely
sampled by LAMOST. This algorithm has been implemented for the halo portion of
the LAMOST pilot survey, which began in October 2011.Comment: 17 pages, 7 figures, accepted for publication in RA
Postoperative serum squamous cell carcinoma antigen and carcinoembryonic antigen predict overall survival in surgical patients with esophageal squamous cell carcinoma
BackgroundTumor markers are routinely used in clinical practice. However, for resectable patients with esophageal squamous cell carcinoma (ESCC), they are applied infrequently as their prognostic significance is incompletely understood.MethodsThis historical cohort study included 2769 patients with resected ESCC from 2011 to 2018 in a high-risk area in northern China. Their clinical data were extracted from the Electronic Medical Record. Survival analysis of eight common tumor markers was performed with multivariable Cox proportional hazards regressions.ResultsWith a median follow-up of 39.5 months, 901 deaths occurred. Among the eight target markers, elevated postoperative serum SCC (Squamous cell carcinoma antigen) and CEA (Carcinoembryonic antigen) predicted poor overall survival (SCC HRadjusted: 2.67, 95% CI: 1.70-4.17; CEA HRadjusted: 2.36, 95% CI: 1.14-4.86). In contrast, preoperative levels were not significantly associated with survival. Stratified analysis also demonstrated poorer survival in seropositive groups of postoperative SCC and CEA within each TNM stage. The above associations were generally robust using different quantiles of concentrations above the upper limit of the clinical normal range as alternative cutoffs. Regarding temporal trends of serum levels, SCC and CEA were similar. Their concentrations fell rapidly after surgery and thereafter remained relatively stable.ConclusionPostoperative serum SCC and CEA levels predict the overall survival of ESCC surgical patients. More importance should be attached to the use of these markers in clinical applications
LAMOST Experiment for Galactic Understanding and Exploration (LEGUE) The survey science plan
We describe the current plans for a spectroscopic survey of millions of stars
in the Milky Way galaxy using the Guo Shou Jing Telescope (GSJT, formerly the
Large Area Multi-Object Spectroscopic Telescope - LAMOST). The survey will
obtain spectra for 2.5 million stars brighter than during dark/grey
time, and 5 million stars brighter than or on nights that are
moonlit or have low transparency. The survey will begin in fall of 2012, and
will run for at least four years. The telescope design constrains the optimal
declination range for observations to , and site
conditions lead to an emphasis on stars in the direction of the Galactic
anticenter. The survey is divided into three parts with different target
selection strategies: disk, anticenter, and spheroid. The resulting dataset
will be used to study the merger history of the Milky Way, the substructure and
evolution of the disks, the nature of the first generation of stars through
identification of the lowest metallicity stars, and star formation through
study of open clusters and the OB associations. Detailed design of the LEGUE
survey will be completed after a review of the results of the pilot survey in
summer 2012.Comment: 19 pages, 1 figure, accepted for publication in RA
Search for the decay
We search for radiative decays into a weakly interacting neutral
particle, namely an invisible particle, using the produced through the
process in a data sample of
decays collected by the BESIII detector
at BEPCII. No significant signal is observed. Using a modified frequentist
method, upper limits on the branching fractions are set under different
assumptions of invisible particle masses up to 1.2 . The upper limit corresponding to an invisible particle with zero mass
is 7.0 at the 90\% confidence level
First observations of hadrons
Based on events collected with
the BESIII detector, five hadronic decays are searched for via process
. Three of them, ,
, and are observed for the first
time, with statistical significances of 7.4, , and
9.1, and branching fractions of ,
, and ,
respectively, where the first uncertainties are statistical and the second
systematic. No significant signal is observed for the other two decay modes,
and the corresponding upper limits of the branching fractions are determined to
be and at 90% confidence level.Comment: 17 pages, 16 figure
Observation of in
Using a sample of events recorded with
the BESIII detector at the symmetric electron positron collider BEPCII, we
report the observation of the decay of the charmonium state
into a pair of mesons in the process
. The branching fraction is measured for the first
time to be , where the first uncertainty is
statistical, the second systematic and the third is from the uncertainty of
. The mass and width of the are
determined as MeV/ and
MeV.Comment: 13 pages, 6 figure
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