478 research outputs found
SPECT-CT localization of axillary sentinel lymph nodes for radiotherapy of early breast cancer
PurposeTo evaluate the opportunities of single photon emission tomography/computerized tomography (SPECT-CT) for localization of axillary sentinel lymph nodes (ASLNs) and subsequent radiotherapy planning in women with early breast cancer.Material and methodsIndividual topography of ASLN was determined in 151 women with clinical T1-2N0M0 breast cancer. SPECT-CT visualization of ASLNs was initiated 120min after intra-peritumoral injection of 99mTc-radiocolloids. Doses absorbed by virtual ASLNs after the whole breast irradiation with standard and extended tangential fields were calculated on a treatment planning station.ResultsSPECT-CT demonstrated a large variability of ASLN localization. They were detected in the central subgroup in 94 (61%) patients, in pectoral â in 77 (51%), and in interpectoral â in 4 (3%) patients. Sentinel lymph nodes âlying on the chestâ were revealed in 35 (23%) cases.We found that with standard tangential fields coverage of ASLNs was obtained only in 20% of evaluated women. Extended tangential fields can effectively irradiate ASLNs localized in all axillary sub-regions with the exception of ASLNs âlying on the chestâ.ConclusionSPECT-CT mapping of ASLNs in women with cT1-2N0M0 breast cancer reveals their variable localization. This information can be important for planning of radiation treatment in women that underwent breast conserving surgery without an axillary surgery
Cannabidiol improves memory and decreases IL-1ÎČ serum levels in rats with lipopolysaccharide-induced inflammation
Aim: Memory improving and anti-inflammatory properties of cannabidiol (CBD) were investigated in an experimental model of lipopolysaccharide (LPS)-induced inflammation. Materials and methods: Male Wistar rats were randomly divided into 4 groups: control, LPS control, LPS + CBD 5 mg/kg bw, and LPS + CBD 10 mg/kg bw. Animals were treated with CBD 14 days before LPS administration and throughout the experiment. Step-through passive avoidance task, Y-maze, and novel object recognition test (NORT) were used to assess the memory functions. The following parameters were recorded: latency time, spontaneous alternations percentage (SA%) and recognition index (RI). IL-10, IL-6, TNF-α, and IL-1ÎČ serum levels were measured to evaluate the immunomodulatory properties of CBD. Results: LPS led to significant decrease of the recorded parameters in all memory tasks. This demonstrated the memory-impairing effect of LPS-induced inflammation. In the Y-maze and NORT tests, both doses of CBD increased SA% and RI, respectively. Significant difference was found in comparison with the LPS controls. Rats from the CBD treated groups showed increased latency in the step-through passive avoidance task. In the short-term memory test, both CBD doses significantly increased this parameter when compared with both control groups (p<0.05 and p<0.001, respectively), whereas in the long-term memory test, statistical significance was reached only in comparison with the LPS controls (p<0.01). CBD treatment failed to reduce TNF-α and IL-6 serum levels. The lower studied dose significantly decreased IL-10 and IL-1ÎČ concentrations compared to LPS controls (p<0.01 and p<0.05, respectively). Conclusions: CBD improved spatial working and recognition memory in rats with LPS-induced inflammation. Suppression of IL-1ÎČ production could be attributed to the observed effect
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
Self-Action Effects for the Laser Radiation Scattered by Metal Nanoparticles
The self-action effects of the laser radiation incident on metal nanoparticles of spherical shape are analyzed within the framework of a free-electron model and a phenomenological description of the nonlinear electrodynamic properties of the metal surfac
An Economic Model of Sustainable Development in the Russian Arctic: The Idea of Building Vertical Farms
The main aim of the article is to find out the key factors of sustainable development of the Russian Arctic, which is strategically significant for Russia. The academic literature was reviewed to find out the time dynamics of the references to the economic models suitable for achieving the goals of sustainable development, and there has been hyperbolic growth in the attention paid to similar problems all around the world. The article compares three relatively new economic models in order to understand which of them is the most applicable to the promotion of sustainable development in the Russian Arctic: (a) bioeconomy, (b) green economy and (c) circular economy. The analysis of the relevant sources shows that the model of the circular economy is preferable for the Russian Arctic. Most of the article is dedicated to understanding the sources and mechanisms of the circular economy. The schematic description of vertical greenhouses and possibility of using vertical farms are presented in the paper as an example of organization of local food production according to the principles of the circular economy. The article considers a modeled project of creating a vertical farm in the Russian Arctic and a simulated indicatorâprofit of the vertical farm
Influence of Schumann Range Electromagnetic Fields on Components of Plant Redox Metabolism in Wheat and Peas
The Schumann Resonances (ScR) are Extremely Low Frequency (ELF) electromagnetic resonances in the Earth-ionosphere cavity excited by global lightning discharges. ScR are the part of electromagnetic field (EMF) of Earth. The influence of ScR on biological systems is still insufficiently understood. The purpose of the study is to characterize the possible role of the plant cell redox metabolism regulating system in the Schumann Resonances EMF perception. Activity of catalase and superoxide dismutase, their isoenzyme structure, content of malondialdehyde, composition of polar lipids in leaf extracts of wheat and pea plants treated with short-time (30 min) and long-time (18 days) ELF EMF with a frequency of 7.8 Hz, 14.3 Hz, 20.8 Hz have been investigated. Short-time exposure ELF EMF caused more pronounced bio effects than long-time exposure. Wheat catalase turned out to be the most sensitive parameter to magnetic fields. It is assumed that the change in the activity of wheat catalase after a short-term ELF EMF may be associated with the ability of this enzyme to perceive the action of a weak EMF through calcium calmodulin and/or cryptochromic signaling systems
Intrinsic detection efficiency of superconducting nanowire single-photon detectors with different thicknesses
We evaluate experimentally the intrinsic detection efficiency IDE of superconducting NbN
nanowire single-photon detectors in the range of wire thicknesses from 4 to 12 nm. The study is
performed in the broad spectral interval between near-ultraviolet wavelength 400 nm and
near-infrared wavelength 2000 nm light with plane waves at normal incidence. For visible light the
IDE of the thinnest detectors reaches 70%. We use numerically computed absorptance of the
nanowire-structures for the analysis of the experimental data. Variations in the detection efficiency
with both the wire thickness and the wavelength evidence the red boundary of the hot-spot
photon-detection mechanism. We explain the detection at larger wavelengths invoking thermal
excitation of magnetic Pearl vortices over the potential barrier at the edges of the wire
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