11 research outputs found
Error threshold in optimal coding, numerical criteria and classes of universalities for complexity
The free energy of the Random Energy Model at the transition point between
ferromagnetic and spin glass phases is calculated. At this point, equivalent to
the decoding error threshold in optimal codes, free energy has finite size
corrections proportional to the square root of the number of degrees. The
response of the magnetization to the ferromagnetic couplings is maximal at the
values of magnetization equal to half. We give several criteria of complexity
and define different universality classes. According to our classification, at
the lowest class of complexity are random graph, Markov Models and Hidden
Markov Models. At the next level is Sherrington-Kirkpatrick spin glass,
connected with neuron-network models. On a higher level are critical theories,
spin glass phase of Random Energy Model, percolation, self organized
criticality (SOC). The top level class involves HOT design, error threshold in
optimal coding, language, and, maybe, financial market. Alive systems are also
related with the last class. A concept of anti-resonance is suggested for the
complex systems.Comment: 17 page
Search for directional associations between Baikal Gigaton Volume Detector neutrino-induced cascades and high-energy astrophysical sources
Baikal-GVD has recently published its first measurement of the diffuse
astrophysical neutrino flux, performed using high-energy cascade-like events.
We further explore the Baikal-GVD cascade dataset collected in 2018-2022, with
the aim to identify possible associations between the Baikal-GVD neutrinos and
known astrophysical sources. We leverage the relatively high angular resolution
of the Baikal-GVD neutrino telescope (2-3 deg.), made possible by the use of
liquid water as the detection medium, enabling the study of astrophysical point
sources even with cascade events. We estimate the telescope's sensitivity in
the cascade channel for high-energy astrophysical sources and refine our
analysis prescriptions using Monte-Carlo simulations. We primarily focus on
cascades with energies exceeding 100 TeV, which we employ to search for
correlation with radio-bright blazars. Although the currently limited neutrino
sample size provides no statistically significant effects, our analysis
suggests a number of possible associations with both extragalactic and Galactic
sources. Specifically, we present an analysis of an observed triplet of
neutrino candidate events in the Galactic plane, focusing on its potential
connection with certain Galactic sources, and discuss the coincidence of
cascades with several bright and flaring blazars.Comment: 10 pages, 3 figure
Large neutrino telescope Baikal-GVD: recent status
The Baikal-GVD is a deep-underwater neutrino telescope being constructed in
Lake Baikal. After the winter 2023 deployment campaign the detector consists of
3456 optical modules installed on 96 vertical strings. The status of the
detector and progress in data analysis are discussed in present report. The
Baikal-GVD data collected in 2018-2022 indicate the presence of cosmic neutrino
flux in high-energy cascade events consistent with observations by the IceCube
neutrino telescope. Analysis of track-like events results in identification of
first high-energy muon neutrino candidates. These and other results from
2018-2022 data samples are reviewed in this report
OPPORTUNITIES OF LAPAROSCOPY IN THE TREATMENT OF ESOPHAGEAL ACHALASIA
The article describes opportunities and results of laparoscopic oesophagocardiomiotomy and laparoscopic transhiatal oesophagus removal without hand assistance in esophageal achalasia (cardiospasm). In total, such operations were performed in 196 and 31 of cases (of 423 patients), respectively. There were minimal numbers of relapses (below 2.3%) after laparoscopic oesophagocardiomiotomy done by the proposed technique. All cases of reflux esophagitis were diagnosed after esophagocardiomiotomy with Dor fundoplication.After cardiodilatation, disease relapses were registered in 57% of patients. The advantages of a laparoscopic access for oesophagectomy are shown and technical particular of this intervention are analyzed based on a case history. The principles of Fast track surgery in this patient category are discussed that allow for reduction of the length of hospital stay by 40%
ANTARES offline study of three alerts after Baikal-GVD follow-up found coincident cascade neutrino events
ANTARES and Baikal-GVD are both Cherenkov neutrino telescopes located in the Northern Hemisphere so their fields of view almost overlap allowing for a combined study of the sky. ANTARES sends alerts after a fast online analysis based on energy and reconstruction direction of track-like events. From December of 2018 until the beginning of 2021, Baikal-GVD received 38 ANTARES alerts, and followed up 32. No coincidence was found. However, a search of the Baikal-GVD cascade sample showed some events falling within an angular distance of less than 5° for three of the ANTARES alerts in a time span of 48 hours. A dedicated offline analysis based on the full ANTARES data sample has been started to search for additional coincident tracks and cascades at a 3σ significance. In this work we present the final results of the offline analysis of the three ANTARES alerts: limits on the astrophysical neutrino fluence are reported