232 research outputs found
Insights into the metabolic profiling of Polygonati Rhizoma fermented by Lactiplantibacillus plantarum under aerobic and anaerobic conditions using a UHPLC-QE-MS/MS system
IntroductionPolygonati Rhizoma is a multi-purpose food with medicinal uses. Fermentation of Polygonati Rhizoma by lactic acid bacteria could provide new insights into the development of Polygonati Rhizoma products.MethodsIn this study, Lactiplantibacillus plantarum was fermented with Polygonati Rhizoma extracts in a bioreactor under aerobic and anaerobic conditions with pH and DO real-time detection. Metabolic profiling was determined by UHPLC-QE-MS/MS system. Principal component analysis and orthogonal partial least-squares discriminant analysis were used to perform multivariate analysis.ResultsA total of 98 differential metabolites were identified in broth after fermentation, and 36 were identified between fermentation under aerobic and anaerobic conditions. The main metabolic pathways in the fermentation process are ABC transport and amino acid biosynthesis. Most of the compounds such as L-arginine, L-aspartic acid, leucine, L-lysine, citrate, inosine, carnitine, betaine, and thiamine were significantly increased during fermentation, playing a role in enhancing food flavor. Compared with anaerobic fermentation, aerobic conditions led to a significant rise in the levels of some compounds such as valine, isoleucine, and glutamate; this increase was mainly related to branched-chain amino acid transaminase, isocitrate dehydrogenase, and glutamate dehydrogenase.DiscussionAerobic fermentation is more beneficial for the fermentation of Polygonati Rhizoma by L. plantarum to produce flavor and functional substances. This study is the first report on the fermentation of Polygonati Rhizoma by L. plantarum and provides insights that would be applicable in the development of Polygonati Rhizoma fermented products
Implementation and performances of the IPbus protocol for the JUNO Large-PMT readout electronics
The Jiangmen Underground Neutrino Observatory (JUNO) is a large neutrino
detector currently under construction in China. Thanks to the tight
requirements on its optical and radio-purity properties, it will be able to
perform leading measurements detecting terrestrial and astrophysical neutrinos
in a wide energy range from tens of keV to hundreds of MeV. A key requirement
for the success of the experiment is an unprecedented 3% energy resolution,
guaranteed by its large active mass (20 kton) and the use of more than 20,000
20-inch photo-multiplier tubes (PMTs) acquired by high-speed, high-resolution
sampling electronics located very close to the PMTs. As the Front-End and
Read-Out electronics is expected to continuously run underwater for 30 years, a
reliable readout acquisition system capable of handling the timestamped data
stream coming from the Large-PMTs and permitting to simultaneously monitor and
operate remotely the inaccessible electronics had to be developed. In this
contribution, the firmware and hardware implementation of the IPbus based
readout protocol will be presented, together with the performances measured on
final modules during the mass production of the electronics
Mass testing of the JUNO experiment 20-inch PMTs readout electronics
The Jiangmen Underground Neutrino Observatory (JUNO) is a multi-purpose,
large size, liquid scintillator experiment under construction in China. JUNO
will perform leading measurements detecting neutrinos from different sources
(reactor, terrestrial and astrophysical neutrinos) covering a wide energy range
(from 200 keV to several GeV). This paper focuses on the design and development
of a test protocol for the 20-inch PMT underwater readout electronics,
performed in parallel to the mass production line. In a time period of about
ten months, a total number of 6950 electronic boards were tested with an
acceptance yield of 99.1%
Validation and integration tests of the JUNO 20-inch PMTs readout electronics
The Jiangmen Underground Neutrino Observatory (JUNO) is a large neutrino
detector currently under construction in China. JUNO will be able to study the
neutrino mass ordering and to perform leading measurements detecting
terrestrial and astrophysical neutrinos in a wide energy range, spanning from
200 keV to several GeV. Given the ambitious physics goals of JUNO, the
electronic system has to meet specific tight requirements, and a thorough
characterization is required. The present paper describes the tests performed
on the readout modules to measure their performances.Comment: 20 pages, 13 figure
Real-time Monitoring for the Next Core-Collapse Supernova in JUNO
Core-collapse supernova (CCSN) is one of the most energetic astrophysical
events in the Universe. The early and prompt detection of neutrinos before
(pre-SN) and during the SN burst is a unique opportunity to realize the
multi-messenger observation of the CCSN events. In this work, we describe the
monitoring concept and present the sensitivity of the system to the pre-SN and
SN neutrinos at the Jiangmen Underground Neutrino Observatory (JUNO), which is
a 20 kton liquid scintillator detector under construction in South China. The
real-time monitoring system is designed with both the prompt monitors on the
electronic board and online monitors at the data acquisition stage, in order to
ensure both the alert speed and alert coverage of progenitor stars. By assuming
a false alert rate of 1 per year, this monitoring system can be sensitive to
the pre-SN neutrinos up to the distance of about 1.6 (0.9) kpc and SN neutrinos
up to about 370 (360) kpc for a progenitor mass of 30 for the case
of normal (inverted) mass ordering. The pointing ability of the CCSN is
evaluated by using the accumulated event anisotropy of the inverse beta decay
interactions from pre-SN or SN neutrinos, which, along with the early alert,
can play important roles for the followup multi-messenger observations of the
next Galactic or nearby extragalactic CCSN.Comment: 24 pages, 9 figure
Measurement of the -even fraction of
A determination of the -even fraction in the decay is presented. Using fb of
data collected by the BESIII detector, one
charm meson is reconstructed in the signal mode and the other in a
eigenstate or the decay . Analysis of the relative
rates of these double-tagged events yields the result , where the first uncertainty is statistical and the second is
systematic. This is the first model-independent measurement of in decays.Comment: 13 pages, 5 figure
Production of doubly-charged baryon in annihilation at energies from 2.3094 to 2.6464 GeV
The processes and
are studied for the first
time with of annihilation data collected with
the BESIII detector at center-of-mass energies from GeV to
GeV. No significant signal for the
process is observed and the upper limit of the Born cross section is estimated
at each energy point. For the process , a significant signal is observed at center-of-mass energies
near 2.6454 GeV and the corresponding Born cross section is reported.Comment: 10 pages, 4 figure
Search for an invisible muon philic scalar or vector via decay at BESIII
A light scalar or vector particles have been introduced as a
possible explanation for the anomaly and dark matter phenomena.
Using \jpsi events collected by the BESIII
detector, we search for a light muon philic scalar or vector in
the processes with invisible decays. No
obvious signal is found, and the upper limits on the coupling
between the muon and the particles are set to be between
and for the mass in the range
of ~MeV at 90 confidence level.Comment: 9 pages 7 figure
First Observation of a Three-Resonance Structure in {non-open} Charm Hadrons
We report the measurement of the cross sections for
{nOCH} (nOCH stands for non-open charm hadrons) with
improved precision at center-of-mass energies from 3.645 to 3.871 GeV. We
observe for the first time a three-resonance structure in the energy-dependent
lineshape of the cross sections, which are , and with significances of ,
, and , respectively. The is observed
for the first time. We found two solutions in analysis of the cross sections.
For solution I [solution II], we measure the mass, the total width and the
product of electronic width and nOCH decay branching fraction to be [] MeV/, [] MeV, and [] eV for the , respectively. In addition, we
measure the branching fractions {nOCH} for the first time, and {nOCH}. Moreover, we determine the open-charm (OC) branching fraction
{OC}, which supports the interpretation of as an OC pair molecular state, but contained a simple four-quark state
component. The first uncertainties are from fits to the cross sections, and the
second are systematic
Measurement of the cross sections from 2.000 to 3.080 GeV
Based on collision data collected at center-of-mass energies
from 2.000 to 3.080 GeV by the BESIII detector at the BEPCII collider, a
partial wave analysis is performed for the process . The results allow the Born cross sections of the process
, as well as its subprocesses
and to be
measured. The Born cross sections for are consistent with previous measurements by BaBar and SND,
but with substantially improved precision. The Born cross section lineshape of
the process is consistent with a vector
meson state around 2.2 GeV with a statistical significance of 3.2. A
Breit-Wigner fit determines its mass as
and its width as
, where the first uncertainties are
statistical and the second ones are systematic, respectively
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