602 research outputs found
Arborinol methyl ether from Areca catechu L.
The title compound isolated from Areca catechu L. (common name: arborinol methyl ether; a member of the arborane family) was established as 3α-methoxyarbor-9(11)-ene, C31H52O. Rings A/B/C/D assume a chair conformation, while ring E has an envelope conformation. The absolute configuration was determined to be (3R,5R,8S,10S,13R,14S,17S,18S, 21S) by analysis of Bijvoet pairs based on resonant scattering of light atoms, yielding a Hooft parameter y of â0.03â
(3)
Oxyresveratrol from Mulberry as a dihydrate
The title compound {systematic name: 4-[(E)-2-(3,5-dihyÂdroxyÂphenÂyl)ethenÂyl]benzene-1,3-diol dihydrate}, C14H12O4·2H2O, a derivative of resveratrol, was isolated from mulberry. The linking C=C double bond has a trans conformation and allows the formation of a conjugated system throughout the molÂecule. The dihedral angle between the benzene rings is 9.39â
(9)°. In the crystal, molÂecules are connected into a three-dimensional architecture through OâHâŻO hydrogen bonds between hyÂdroxy groups of oxyresveratrol and solvent water molÂecules
Multidifferential study of identified charged hadron distributions in -tagged jets in proton-proton collisions at 13 TeV
Jet fragmentation functions are measured for the first time in proton-proton
collisions for charged pions, kaons, and protons within jets recoiling against
a boson. The charged-hadron distributions are studied longitudinally and
transversely to the jet direction for jets with transverse momentum 20 GeV and in the pseudorapidity range . The
data sample was collected with the LHCb experiment at a center-of-mass energy
of 13 TeV, corresponding to an integrated luminosity of 1.64 fb. Triple
differential distributions as a function of the hadron longitudinal momentum
fraction, hadron transverse momentum, and jet transverse momentum are also
measured for the first time. This helps constrain transverse-momentum-dependent
fragmentation functions. Differences in the shapes and magnitudes of the
measured distributions for the different hadron species provide insights into
the hadronization process for jets predominantly initiated by light quarks.Comment: All figures and tables, along with machine-readable versions and any
supplementary material and additional information, are available at
https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-013.html (LHCb
public pages
Study of the decay
The decay is studied
in proton-proton collisions at a center-of-mass energy of TeV
using data corresponding to an integrated luminosity of 5
collected by the LHCb experiment. In the system, the
state observed at the BaBar and Belle experiments is
resolved into two narrower states, and ,
whose masses and widths are measured to be where the first uncertainties are statistical and the second
systematic. The results are consistent with a previous LHCb measurement using a
prompt sample. Evidence of a new
state is found with a local significance of , whose mass and width
are measured to be and , respectively. In addition, evidence of a new decay mode
is found with a significance of
. The relative branching fraction of with respect to the
decay is measured to be , where the first
uncertainty is statistical, the second systematic and the third originates from
the branching fractions of charm hadron decays.Comment: All figures and tables, along with any supplementary material and
additional information, are available at
https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-028.html (LHCb
public pages
Measurement of the ratios of branching fractions and
The ratios of branching fractions
and are measured, assuming isospin symmetry, using a
sample of proton-proton collision data corresponding to 3.0 fb of
integrated luminosity recorded by the LHCb experiment during 2011 and 2012. The
tau lepton is identified in the decay mode
. The measured values are
and
, where the first uncertainty is
statistical and the second is systematic. The correlation between these
measurements is . Results are consistent with the current average
of these quantities and are at a combined 1.9 standard deviations from the
predictions based on lepton flavor universality in the Standard Model.Comment: All figures and tables, along with any supplementary material and
additional information, are available at
https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-039.html (LHCb
public pages
Catalytic Activity of ZrO2 Nanotube Arrays Prepared by Anodization Method
ZrO2 nanotube arrays were prepared by anodization method in aqueous electrolyte containing (NH4)2SO4 and NH4F. The morphology and structure of nanotube arrays were characterized through scanning electron microscope, X-ray diffraction, and infrared spectra analysis. The zirconia nanotube arrays were used as catalyst in esterification reaction. The effects of calcination temperature and electrolyte concentration on catalytic esterification activity have been investigated in detail. Experiments indicate that nanotube arrays have highest catalytic activity when the concentration of (NH4)2SO4 is 1âmol/L, the concentration of NH4F is 1âwt%, and the calcination temperature is 400°C. Esterification reaction yield of as much as 97% could be obtained under optimal conditions
Experimental study of dynamic strain for gear tooth using fiber Bragg gratings and piezoelectric strain sensors
A review on the hybrids of hydroxycinnamic acid as multi-target-directed ligands against Alzheimer's disease
Alzheimer's disease (AD), a complex chronic progressive central nervous system degenerative disease and a public health problem of the world, often characters cognitive dysfunction accompaning aggression and depression, and may lead to death. More attentions should be paid on it because there is no modified strategy against AD till now. AD is featured with the loss of cholinergic neurons, the amyloid-beta peptide (AĂÂČ) plaques and the neurofibrillary tangles and several hypotheses were established to explain the pathogenesis of AD. Hydroxycinnamic acids, including caffeic acid (CA) and ferulic acid (FA) are widely distributed in natural plants and fruits. CA and FA exert various pharmacological activities, including anti-inflammatory, antioxidant, neuroprotection, anti-amyloid aggregation and so on. All these pharmacological activities are associated with the treatment of AD. Here we summarized the pharmacological activities of CA and FA, and their hybrids as multi-target-directed ligands (MTDLs) against AD. The future application of CA and FA was also discussed, hoping to provide beneficial information for the development of CA- and FA-based MTDLs against AD
Chinese experts consensus for aerosol therapy assisted by Internet of Things
Aerosol inhalation treatment imposes direct effects on target organs with less systematic side effects and no need of deliberate cooperation of patients. However, the lack of resources and experience impairs the drug efficacy and even causes side effects. The editorial board of International Journal of Respiration reviewed the literature, discussed and summarized their experience, and finalized the Chinese experts consensus on the treatment of aerosol inhalation assisted by Internet of Things. This practice guideline was designed to guide medical staffs at all levels to carry out standardized aerosol inhalation treatment more properly. Keywords: Aerosol inhalation, Indications, Therapeutic schedules, Safety, Side effects, Internet of Thing
Multi-targeted ChEI-copper chelating molecules as neuroprotective agents
The identification of a valid therapeutic treatment for Alzheimer's disease (AD)represents nowadays an urgent and still unmet medical need, since currently available anti-AD drugs only relieve symptoms and show a modest efficacy. Recent evidence indicates that multi-target-directed ligands (MTDLs)can potentially provide an effective strategy to develop innovative therapies directed towards the onset and progression of this multifactorial neurodegenerative disorder. In this work we designed, synthesized and evaluated a new series of MTDLs bearing the rivastigmine skeleton (ChE-inhibitor)linked to known metal-chelating moieties with linkers of different length. For all the novel derivatives, AChE/BuChE inhibitory activity, ROS scavenging activity and potential cytotoxicity have been assessed. For the best compound (4), copper chelating properties and neuroprotective effects were also evaluated. Our data demonstrated that hybrid derivative 4 is able to effectively inhibit AChE and BuChE and to chelate copper, showing a protective action on neurons. These results, although preliminary, indicate that compound 4 can be considered as a possible hit molecule for the development of new anti-AD MTDLs
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