92,261 results on '"A. A. Kuznetsov"'
Search Results
2. Development method of determining angle of the railway contact network support inclination
- Author
-
I. A. Shnyptev, R. S. Kurmanov, Yu. M. Sosnovsky, and A. A. Kuznetsov
- Subjects
overhead contact line support ,tilt angle ,diagnostics ,laser scanning rangefinder ,unmanned aerial vehicle ,video camera ,minimum distance method ,railway transport safety ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
This paper discusses a new method for measuring and calculating the angle of inclination of a railway support or a contact network support, using an unmanned aerial vehicle flying along a straight path, parallel to the railway track. A review of existing measurement methods is carried out, their advantages and disadvantages are indicated. In the method under consideration, it is proposed to measure angles and distances with six laser scanning rangefinders installed in threes on horizontal and inclined planes on an unmanned aerial vehicle. This allows you to increase the speed and accuracy of determining the angle of inclination of vertical supports. The calculations use the minimum distances from the laser scanning range finder to the top and bottom of the support surface. The formulas use geometric relationships and the cosine theorem to calculate the roll of supports taking into account their taper. Measuring distances and angles three times allows for averaging over them, which significantly increases the accuracy of calculations. A model experiment is carried out on a model of a reinforced concrete contact network support in four orientations. A comparison is made between theoretically calculated and experimentally measured distances and inclination angles. The accuracy of parameter determination complies with regulatory requirements.
- Published
- 2024
- Full Text
- View/download PDF
3. Comparative evaluation of bioavailability of Botulinum toxin A complexed with Tizol (titanium glycerosolvate aquacomplex) versus pure Botulinum toxin A solution for bladder mucosa: an experimental study
- Author
-
S. V. Poroyskiy, D. V. Perlin, O. G. Srussovskaya, N. A. Goncharov, A. A. Kuznetsov, and E. A. Morozov
- Subjects
botulinum toxin a ,tizol, titanium glycerosolvate ,urothelium ,hyperactive bladder ,Diseases of the genitourinary system. Urology ,RC870-923 - Abstract
Introduction. For the treatment of overactive bladder syndrome (OAB), injection of botulinum toxin A (BoNT-A) has been shown to be effective. However, there is a need for a less invasive method for administering BoNT-A, which could significantly expand the treatment options for OAB.Objective. To assess the impact of tizol on the absorption of BoNT-A by the bladder mucosa and compare it to the individual absorption of BoNT-A.Materials & Methods. Dialysis through the mucous membrane of the сalf bladder was used as an experimental model to study changes in bioavailability of BoNT-A complexed with tisol (BoNT-A + T) and pure BoNT-A solution during in vitro experiment. After dialysis, the BoNT-A concentration in both samples was determined using a spectrophotometer. Dialysis curves were plotted according to the data obtained. Kruvchinsky equilibrium dialysis method was used to determine botulinum toxin A bioavailability. The UV spectrophotometry method was used to determine the concentration of BoNT-A in the acceptor medium by reaction of BoNT-A with Benedict's reagent.Results. It was established that the maximum concentration of BoNT-A diffused into the acceptor medium from the blend of the test substance with tizol after nine hours. The area under the curve for dialysis of BoNT-A + T exceeds the area under the curve of pure BoNT-A by almost 20%, suggesting an improvement in the drug's bioavailability when blended with tizol.Conclusion. Based on our experiment, it was found out that the BoNT-A + T has greater bioavailability than a solution of pure BoNT-A. However, the diffusion rate of the component mixture is sufficiently low.
- Published
- 2024
- Full Text
- View/download PDF
4. Comparative effectiveness of different methods of prescribing rosuvastatin and ezetimibe in combination with PCSK9 inhibitors
- Author
-
A. A. Kuznetsov, G. S. Mal, and I. A. Saraev
- Subjects
dyslipidemia ,pcsk9 inhibitors ,alirocumab ,rosuvastatin ,Medicine (General) ,R5-920 - Abstract
Objective: comparative evaluation of the effectiveness of combined lipid-lowering therapy with rosuvastatin and ezetimibe in fixed and separate combinations with PCSK9 inhibitors in patients with very high cardiovascular risk.Materials and methods: 65 study participants were divided into 2 groups depending on the method of combined lipid-lowering therapy and were observed for 5 months on 6 visits. The effectiveness of the hypolipidemic response in each of the studied groups was evaluated.Results: in the group with separate administration of lipid-lowering drugs, the target values of LDL cholesterol reached 50% of patients, the level of LDL cholesterol during 5 months of treatment decreased by 38.22% from 2.25 [1.82; 2.47] mmol/l to 1.39 [1.21; 1.59] mmol/l (p
- Published
- 2024
- Full Text
- View/download PDF
5. Epidemiological Situation on Plague around the World. Forecast of Epizootic Activity of Natural Plague Foci in the Russian Federation for 2024
- Author
-
N. V. Popov, I. G. Karnaukhov, A. A. Kuznetsov, A. N. Matrosov, A. V. Ivanova, K. S. Martsokha, E. V. Kuklev, V. M. Korzun, D. B. Verzhutsky, E. V. Chipanin, A. V. Kholin, A. A. Lopatin, V. M. Dubyansky, U. M. Ashibokov, A. Yu. Gazieva, I. V. Kutyrev, S. V. Balakhonov, A. N. Kulichenko, and V. V. Kutyrev
- Subjects
natural foci of plague ,epizootic activity ,epidemiological surveillance ,preventive measures ,electronic passport ,gis portal ,Infectious and parasitic diseases ,RC109-216 - Abstract
The aim of the review was to assess the epidemiological situation in natural plague foci in the Russian Federation, near and far abroad countries in 2023 and to forecast their epizootic activity for 2024. In 2023, cases of plague were registered in five countries worldwide: the Democratic Republic of the Congo (60 cases), the Republic of Madagascar (14), the United States of America (2), the People’s Republic of China (3), and Mongolia (5). A total of 84 cases of plague were recorded, of which 22 (26.2 %) were fatal. In the Russian Federation, in 2023, epidemic risks in epizootically active natural foci were significantly reduced due to the implementation of a set of preventive measures carried out by Rospotrebnadzor institutions, which was the guarantor of ensuring epidemiological well-being as regards plague. Plague epizootics were detected on the territory of two (Gorno-Altai high-mountain and Tuva mountain) out of 11 natural plague foci in the Russian Federation in 2023. Epizootics were reported on the territory of the Kosh-Agach district of the Altai Republic and the Mongun-Taiginsky kozhuun of the Tuva Republic. The total area of epizootics was 731.2 km2 (in 2022 – 248.3 km2). In total, 55 cultures of the antique biovar of the main subspecies Yersinia pestis pestis were isolated in 2023 (19 in 2022). The forecast for continuation of the tense epidemiological situation in the territory of the Altai and Tuva Republics in 2024 is substantiated. The trend of sustained growth in the epizootic potential of the East Caucasus high-mountain and Dagestan plain-piedmont plague foci is outlined. The prospects for introducing an automated electronic system for assessing the epidemic potential of natural plague foci into practice are explained.
- Published
- 2024
- Full Text
- View/download PDF
6. Defining quantitative parameters and coordinates of the defect signal by acoustic-emission control of cylindrical tanks
- Author
-
A. A. Kuznetsov and V. P. Kulakovskaya
- Subjects
acoustic emission ,defect control ,signal activity ,railway tank ,nondestructive testing ,defect coordinates ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
In this article there is presented the data obtained by researching the acoustic emission signals when controlling the surface defects of sealed tanks. In the process of studies with pressure changes the data on changes in the parameters of the signals recorded by the digital acoustic-emission control system SCAD-16 have been obtained. On the basis of the obtained results the methodology for determining the coordinates of the defects of the tanks using the cylindrical coordinate system has been proposed. The approach proposed in the article makes it possible to reduce the error of determining the coordinates of defects, as compared to the expressions in the case of rectilinear wave propagation on a flat surface.
- Published
- 2024
- Full Text
- View/download PDF
7. Modern Diagnostic Technologies in the Study of the Field Material Collected from the Natural Plague Foci of the Kyrgyz Republic in 2023
- Author
-
S. K. Berdiev, G. A. Eroshenko, A. N. Balykova, N. T. Usenbaev, N. T. Kebekbaeva, A. K. Dzhaparova, Zh. Mukanmetesen uulu, D. Zhumashov, A. Sh. Razhapbaeva, A. M. Yuldasheva, E. G. Oglodin, A. D. Katyshev, A. A. Kuznetsov, A. V. Fadeeva, and V. V. Kutyrev
- Subjects
plague ,natural foci of the kyrgyz republic ,y. pestis strains ,diagnostics ,Infectious and parasitic diseases ,RC109-216 - Abstract
The aim of the work was to analyze the results of investigating the field material obtained from natural plague foci of the Kyrgyz Republic (KR) in 2023, using modern diagnostic technologies.Materials and methods. 1435 biological samples from the Tien Shan, Alai and Talas high-mountain foci of the Kyrgyz Republic were studied using conventional methods of laboratory diagnosis of plague: microbiological, immunological, biological; as well as modern molecular-genetic methods. Testing of the obtained samples for the presence of plague pathogen DNA was carried out using RT-PCR; and the presence of antibodies to the plague microbe was detected by enzyme-linked immunosorbent assay (ELISA). Molecular identification of Yersinia pestis strains according to their appurtenance to subspecies, biovars, and phylogenetic lineages was performed by RT-PCR using the method of identifying single-nucleotide substitutions based on the analysis of melting curves of products.Results and discussion. An approach to the molecular identification of Y. pestis strains from plague foci of the KR has been developed and validated through identifying singlenucleotide substitutions using the analysis of product melting curves (HMR-analysis) with a set of designed primers. It has been established that Y. pestis strains isolated in the Sarydzhaz autonomous focus of the Tien Shan high-mountain focus belong to the biovar antiqua of the main subspecies, phylogenetic branch 0.ANT5. The phylogenetic relation of Y. pestis strains isolated in 2023 was studied based on genome-wide SNP analysis. Areas of epizootic activity in Eastern Alai have been identified. The data obtained indicate the sustained activation of plague foci in the KR. Areas of the territory of the KR that are promising for paleogenomic research are also discussed.
- Published
- 2024
- Full Text
- View/download PDF
8. Improving the accuracy of determining corrosion products in reinforced concrete structures by atomic emission spectrum analysis
- Author
-
A. A. Kuznetsov, N. V. Volkova, K. I. Fomichenko, and D. M. Korshunov
- Subjects
concrete ,corrosion products ,atomic emission spectral analysis ,laserinduced breakdown spectroscopy ,calibration graph ,error components ,stable calibration function ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
To determine the composition of inhomogeneous samples using the method of laser-spark emission spectrometry, calibration dependences are used, which can have significant systematic errors that significantly affect the determination of the quantitative composition of elements. Sample inhomogeneity also causes inaccuracies in replicate measurements. To reduce errors, multi-signal calibration and internal standard methods are used, which can significantly improve accuracy when changing experimental conditions and eliminate the need to purchase ex-pensive standard samples.
- Published
- 2023
- Full Text
- View/download PDF
9. Software package «Integral» for modeling space constellations and space vehicles
- Author
-
N. A. Zavialova, S. S. Negodyaev, A. A. Kuznetsov, I. N. Zavialov, I. I. Fukin, V. Yu. Semaka, and P. A. Grishin
- Subjects
multi-satellite constellations ,spacecraft ,mathematical modeling ,science-intensive software package ,remote sensing ,space communication ,space monitoring ,Motor vehicles. Aeronautics. Astronautics ,TL1-4050 - Abstract
The aim of the work was to create a software package for modeling the solution of target problems by multi-satellite constellations. The software consists of modules for the dynamics of the center of mass of the satellites, remote sensing of the Earth, satellite communications (including routing of messages over inter-satellite communications), space monitoring and others. The main feature of the implementation was the mathematical and computational optimization of calculations, which made it possible to carry them out on a conventional computer without involving additional computational power. In the course of the work, corrections to the Everhart method were proposed to improve the trajectory integration step. Parallel implementation also helped to significantly speed up the calculations. To illustrate the work, examples of solving two different problems are given: calculating the optimal orbit for the task of monitoring outer space and solving the problem of determining the minimum number of satellites needed to scan the border of the Russian Federation once every half an hour. A feature of the soft is the work with the constellation as an integral object at the level of setting tasks and the subsequent analytics of its solution, which is presented in the form of information on target tasks, subgroups of the constellation, spacecraft and the entire constellation.
- Published
- 2023
- Full Text
- View/download PDF
10. Devices for express diagnostics of power semiconductor devices and semiconductor converters
- Author
-
E. B. Koroleva, S. M. Kurmashev, K. K. Kim, A. A. Tkachuk, and A. A. Kuznetsov
- Subjects
semiconductor device ,express diagnostics ,reverse current ,communication resistors ,analog-to-digital converter ,methodical measurement error ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
The increase in the power of power semiconductor converters operated in the railway industry is associated with the use of group connections of power semiconductor devices in them, the variation in the parameters of which, and, therefore, their unequal load, causes a decrease in the reliability of the power semiconductor converters as a whole. In this regard, it becomes necessary to develop and implement innovative methods and devices for express diagnostics in order to identify potentially unreliable semiconductor devices, and the implementation of technical diagnostics should not be associated with dismantling the electrical circuits of the converters. The method is proposed for determining potentially unreliable power semiconductor devices in group connections based on the results of analyzing the distribution of reverse currents in parallel branches, which made it possible to create a series of devices for diagnosing power semiconductor devices in converters, both with and without communication resistors. The methodological error of measurements made using the developed express diagnostics devices of the transducers do not exceed the standard value equal to 10 %.
- Published
- 2023
- Full Text
- View/download PDF
11. Results of a Joint Epizootiological Survey of Transboundary Natural Plague Foci of the Russian Federation and Potentially Focal Territories of the Republic of Kazakhstan in 2019–2022
- Author
-
A. M. Senichkina, I. N. Sharova, Sh. V. Magerramov, K. S. Zakharov, A. A. Kuznetsov, V. N. Chekashov, A. M. Porshakov, M. G. Korneev, M. V. Proskuryakova, Yu. V. Kislitsyn, A. I. Belyaev, I. B. Kim, L. B. Nurmagambetova, I. G. Kozulina, A. A. Bashmakov, A. A. Bashmakova, A. A. Kovalevskaya, R. I. Adilov, M. P. Grigor’ev, E. V. Kuklev, and A. K. Grazhdanov
- Subjects
epizootiological monitoring ,plague ,natural-focal infectious diseases ,Infectious and parasitic diseases ,RC109-216 - Abstract
Consolidation of the efforts in implementation of epidemiological surveillance and control over plague and other dangerous natural-focal infections is an essential aspect in ensuring epidemiological well-being as regards particularly dangerous infectious diseases in the territory of natural plague foci and potentially focal territories located within the borders of the Russian Federation and the Republic of Kazakhstan. The aim of the work was to carry out a joint epizootiological survey of the transboundary territories of the Volga-Ural sandy natural plague focus and the territory of the East Kazakhstan region of the Republic of Kazakhstan (RK) potentially focal for plague over the period of 2019–2022. Materials and methods. Samples of field materials, collected during the epizootiological survey of the territory of Kazakhstan, were studied using bacteriological, molecular-genetic, and immune-serological methods. Results and discussion. We have obtained the current evidence on the spatial-biocenotic structure, the circulation of pathogens of dangerous natural-focal infectious diseases in the transboundary territories of Eastern and Western Kazakhstan. It has been established that the conditions that contribute to the possibility of human infection with plague and other dangerous infectious diseases in case of the aggravation of epizootic situation in the foci or importation of the pathogens into the territory are in place.
- Published
- 2023
- Full Text
- View/download PDF
12. Improvement of Epidemiological Surveillance of Natural Plague Foci of the Russian Federation and the Forecast of Their Epizootic Activity for 2023
- Author
-
N. V. Popov, I. G. Karnaukhov, A. A. Kuznetsov, A. N. Matrosov, A. V. Ivanova, K. S. Martsokha, V. M. Korzun, D. B. Verzhutsky, E. V. Chipanin, A. V. Kholin, A. A. Lopatin, V. M. Dubyansky, U. M. Ashibokov, A. Yu. Gazieva, S. V. Balakhonov, A. N. Kulichenko, and V. V. Kutyrev
- Subjects
natural plague foci ,epizootic activity ,epizootiological forecast ,preventive measures ,electronic certification ,gis portal ,Infectious and parasitic diseases ,RC109-216 - Abstract
The aim of the work was to assess the epidemic situation on plague in the world and epizootic activity of natural plague foci of the Russian Federation in 2022. Following the implementation of comprehensive preventive interventions plans, there was a decrease in the epizootic activity of the Gorno-Altai high-mountain and Tuva mountain natural foci, the cessation of plague epizootics in the Central Caucasian high-mountain focus. The total area of epizootics in the Russian Federation in 2022 reached 248.3 km2, which is 7 times less than in 2021. Infected animals were not found in the Tersko-Sunzhensky low-mountain, Dagestan plain-piedmont, Caspian North-Western steppe, Volga-Ural steppe, Trans-Baikal steppe, Volga-Ural sandy, Caspian sandy, East Caucasian high-mountain natural foci. Persistence of tense epizootiological situation in 2023 is predicted for the territory of the Altai Republic and the Republic of Tuva. The prospects of using the GIS portal of the Russian Anti-Plague Institute “Microbe” of the Rospotrebnadzor for an operational assessment of the actual epidemiological situation in natural plague foci are substantiated.
- Published
- 2023
- Full Text
- View/download PDF
13. International Integration and Cooperation at the Present stage in the Fight Against Plague and Other Dangerous Infections in the Kyrgyz Republic
- Author
-
S. K. Berdiev, A. K. Dzhaparova, G. A. Eroshenko, A. A. Kuznetsov, and V. V. Kutyrev
- Subjects
plague ,natural foci ,epizootiological survey ,y. pestis strains ,international cooperation ,Infectious and parasitic diseases ,RC109-216 - Abstract
The paper contains the data on international cooperation of the Republican Center of Quarantine and Particularly Dangerous Infections of the Ministry of Health of the Kyrgyz Republic and the Russian Research Anti-Plague Institute “Microbe” of the Rospotrebnadzor to combat plague and other dangerous infections over the period from 2016 to 2022. Areas of cooperation include conducting joint epidemiological monitoring of plague foci in the Kyrgyz Republic; exchange of up-to-date information on the state of natural foci of the two countries; equipping the anti-plague service of the Republic with modern equipment and mobile laboratories, diagnostic tools and technologies; conducting joint exercises to ensure biological safety and prompt response to emergencies; provision of advisory and methodological assistance; training and strengthening of professional personnel; conducting joint scientific researches, conferences; publication of scientific works. Data on the complex characterization of properties and phylogeographic analysis of Yersinia pestis strains isolated during field studies in the Kyrgyz Republic in 2012–2020 are summarized. The prospects for carrying out joint cartographic, molecular-genetic and paleomicrobiological work in the natural foci of the Kyrgyz Republic are outlined.
- Published
- 2023
- Full Text
- View/download PDF
14. Should we encourage the use of robotic technologies in complicated diverticulitis? Results of systematic review and meta-analysis
- Author
-
S. I. Panin, T. V. Nechay, A. V. Sazhin, A. E. Tyagunov, N. A. Shcherbakov, A. V. Bykov, K. Yu Melnikov-Makarchuk, A. G. Yuldashev, and A. A. Kuznetsov
- Subjects
complicated diverticulitis ,robotic technologies in complicated diverticulitis ,robotic surgery ,robotic urgent surgery ,diverticular disease ,Mechanical engineering and machinery ,TJ1-1570 ,Electronic computers. Computer science ,QA75.5-76.95 - Abstract
Introduction: Complicated diverticulitis is a common abdominal emergency that often requires a surgical intervention. The systematic review and meta-analysis below compare the benefits and harms of robotic vs. laparoscopic surgery in patients with complicated colonic diverticular disease.Methods: The following databases were searched before 1 March 2023: Cochrane Library, PubMed, Embase, CINAHL, and ClinicalTrials.gov. The internal validity of the selected non-randomized studies was assessed using the ROBINS-I tool. The meta-analysis and trial sequential analysis were performed using RevMan 5.4 (Cochrane Collaboration, London, United Kingdom) and Copenhagen Trial Unit Trial Sequential Analysis (TSA) software (Copenhagen Trial Unit, Center for Clinical Intervention Research, Rigshospitalet, Copenhagen, Denmark), respectively.Results: We found no relevant randomized controlled trials in the searched databases. Therefore, we analyzed 5 non-randomized studies with satisfactory internal validity and similar designs comprising a total of 442 patients (184 (41.6%) robotic and 258 (58.4%) laparoscopic interventions). The analysis revealed that robotic surgery for complicated diverticulitis (CD) took longer than laparoscopy (MD = 42 min; 95% CI: [-16, 101]). No statistically significant differences were detected between the groups regarding intraoperative blood loss (MD = −9 mL; 95% CI: [–26, 8]) and the rate of conversion to open surgery (2.17% or 4/184 for robotic surgery vs. 6.59% or 17/258 for laparoscopy; RR = 0.63; 95% CI: [0.10, 4.00]). The type of surgery did not affect the length of in-hospital stay (MD = 0.18; 95% CI: [–0.60, 0.97]) or the rate of postoperative complications (14.1% or 26/184 for robotic surgery vs. 19.8% or 51/258 for laparoscopy; RR = 0.81; 95% CI: [0.52, 1.26]). No deaths were reported in either group.Discussion: The meta-analysis suggests that robotic surgery is an appropriate option for managing complicated diverticulitis. It is associated with a trend toward a lower rate of conversion to open surgery and fewer postoperative complications; however, this trend does not reach the level of statistical significance. Since no high quality RCTs were available, this meta-analysis isnot able to provide reliable conclusion, but only a remarkable lack of proper evidence supporting robotic technology. The need for further evidence-based trials is important.
- Published
- 2023
- Full Text
- View/download PDF
15. Design of small capacity meter with linear characteristic
- Author
-
K. K. Kim, A. A. Tkachuk, and A. A. Kuznetsov
- Subjects
capacitive sensor ,dielectric constant ,capacitance meter ,linear measuring characteristic ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
We consider the small-capacity meter with its technical and metrological characteristics in this paper. The diagram of the functional generator and the voltage timing diagrams are given to study operation of the functional generator. The issues of using a capacity meter during the measurement of the parameters of the railway transport devices are considered.
- Published
- 2022
- Full Text
- View/download PDF
16. Algorithm for diagnosing insulation of power transformers by acoustic method in conditions of temperature changes
- Author
-
A. A. Kuznetsov, V. V. Kharlamov, and M. A. Volchanina
- Subjects
power transformers ,acoustic method ,partial discharges ,insulation diagnostics ,defect simulator ,signal parameters ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
The article presents an algorithm for processing data by the acoustic method of insulation power transformers. The article presents data processing of diagnosing by the acoustic method of power transformers. A feature of the power supply system of railway transport is the location of traction substations along the railway track. For diagnosing power transformers advisable to use portable systems based on acoustic monitoring of partial discharges due to their high mobility and ease of installation. To improve the reliability of diagnosis under the conditions of seasonal temperature changes proposed use a defect simulator and a differential method for measuring the parameters of partial discharges. The scheme of the experiment and the diagnostic algorithm are proposed. Expressions are given that describe the properties of transformer oil with temperature changes, and changes in signal parameters during the propagation of acoustic waves. The data of diagnostics obtained on a power transformer at positive and negative temperatures under conditions of development of an insulation defect accompanied by partial discharges are presented.
- Published
- 2022
- Full Text
- View/download PDF
17. Determination of corrosion state of reinforced concrete structures by the parameters of color change in video image
- Author
-
A. A. Kuznetsov, A. V. Ponomarev, A. Yu. Kuzmenko, and G. V. Volchanin
- Subjects
reinforced concrete supports ,corrosion ,leakage currents ,insulators ,visual control ,video image ,color parameters ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
The article shows one of the factors influencing the formation of corrosion of hollow reinforced concrete structures — leakage currents in insulators. The development of corrosion depends on the amount of electricity that has passed through the reinforced concrete. A method for controlling the corrosion state by changing the color parameters on the video image of the reinforced concrete surface is proposed. A full-scale experiment is carried out on samples simulating various degrees of corrosion, as well as on a sample with an unknown level of corrosion. The images are obtained using an industrial endoscope.
- Published
- 2022
- Full Text
- View/download PDF
18. Coronary heart disease and chronic kidney disease: the possibilities of PCSK9 inhibitors in the achievement of atherogenic lipoproteins target values
- Author
-
G. S. Mal and A. A. Kuznetsov
- Subjects
coronary heart disease ,chronic kidney disease ,pcsk9 inhibitors ,alirocumab ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 ,Surgery ,RD1-811 ,Medical emergencies. Critical care. Intensive care. First aid ,RC86-88.9 - Abstract
Objective: Possibilities evaluation of achieving the target values of atherogenic lipoproteins in patients with coronary heart disease (CHD) in combination with renal dysfunction during drug correction with PCSK9 inhibitors.Material and methods: The study included 76 men with CHD with very high cardiovascular risk divided into 2 groups: without chronic kidney disease (CKD) (n = 39) and with stage IIIA–IIIB CKD (n = 37). All patients did not reach the target values of lowdensity lipoprotein cholesterol (LDL cholesterol) after 8 weeks of the maximum dose of atorvastatin and ezetimibe, which was the motivation for the use of PCSK9‑alirocumab inhibitors, with control of the lipid profile and glomerular filtration rate for 6 months.Results: In the group of patients with CHD, 87.1% of patients (n = 34) reached the target values of LDL cholesterol, the level of LDL cholesterol decreased from 4.41 ± 0.19 mmol to 1.28 ± 0.14 mmol (p < 0.001), in the group of patients with CHD + CKD stage IIIA–IIIB 56.7% of patients reached the target values (n = 21), the LDL cholesterol level decreased from 4.6 ± 0.2 mmol to 1.37 ± 0.09 mmol (p < 0.001). There was no statistically significant change in the glomerular filtration rate during the study.Conclusion: The results of this study demonstrate the obvious effectiveness of PCSK9 inhibitors in achieving LDL cholesterol target values in patients with coronary heart disease with a very high cardiovascular risk. During the study, a decrease in the level of LDL cholesterol by more than 70% was noted. The absence of CKD in CHD patients increases the chance of achieving LDL cholesterol target values by 81% (OR 0.19).
- Published
- 2022
- Full Text
- View/download PDF
19. Enhancement of Epidemiological Surveillance in Natural Plague Foci of the Russian Federation and Forecast of Epizootic Activity for 2022
- Author
-
N. V. Popov, I. G. Karnaukhov, A. A. Kuznetsov, A. N. Matrosov, V. A. Safronov, А. M. Porshakov, A. V. Ivanova, K. S. Martsokha, V. M. Korzun, D. B. Verzhutsky, E. V. Chipanin, A. A. Lopatin, V. M. Dubyansky, U. M. Ashibokov, A. Yu. Gazieva, E. S. Zenkevich, S. V. Balakhonov, A. N. Kulichenko, and V. V. Kutyrev
- Subjects
natural plague foci ,epizootic activity ,morbidity ,epizootiological forecast ,preventive measures ,epitracker application ,Infectious and parasitic diseases ,RC109-216 - Abstract
The aim of the research was to assess epizootic activity of natural plague foci in the Russian Federation in 2021 and provide a prognosis for 2022. Activation of epizootic process has been detected in Central-Caucasian high-mountain natural plague focus after a recess since 2007. Local epizootics persist to develop in Tuva Mountain and Gorno-Altai highmountain plague foci. Total area of epizooties in Russia in 2021 amounted to 1649.5 km2. 28 plague microbe strains were isolated. Animals infected with plague were not found in Tersko-Sunzhensky low-mountain, Dagestan plain-piedmont, Precaspian north-western steppe, Volga-Ural steppe, Trans-Baikal steppe, Volga-Ural sandy, Caspian sandy and EastCaucasian high-mountain natural plague foci. It is demonstrated that epidemiological welfare as regards plague in Russia in 2017–2021 was achieved through annual epizootic monitoring of plague-enzootic territories, timely epizooty detection and preventive activities aimed at reducing the risk of infection. Substantiated has been the forecast for tense epidemiological situation on the territory of Karachay-Cherkessia, Kabardino-Balkaria, Altai Republic and Tuva Republic in 2022. A new Epitracker application has been proven to be prospective for rapid assessment of actual epidemiological situation in natural plague foci.
- Published
- 2022
- Full Text
- View/download PDF
20. Electro-corrosive state diagnostics of internal surfaces of reinforced concrete supports of contact network
- Author
-
A. A. Kuznetsov, A. V. Ponomarev, A. G. Zverev, and G. V. Volchanin
- Subjects
hollow reinforced concrete supports ,electrocorrosion state ,diagnostics ,video endoscope ,automated electric drive ,panoramic image ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
The article discusses a device for diagnosing the electrocorrosive state of hollow reinforced concrete supports of the contact network and power lines. The operation of the device is based on the use of a visual method for monitoring electro-corrosive defects. A design of a video endoscope is proposed that provides an improvement in image quality by eliminating fluctuations in the position of a flexible optical probe during its vertical movement, an increase in the level of automation of the diagnostic process with registration of the coordinates of defects and documentary evidence in the form of a replenished database of images of the diagnostic object — the inner surface of hollow reinforced concrete supports from the surface soil to their base.
- Published
- 2021
- Full Text
- View/download PDF
21. Investigation of the spontaneous fission properties of neutron-deficient nobelium isotopes
- Author
-
A. V. Isaev, A. I. Svirikhin, A. V. Andreev, A. V. Yeremin, I. N. Izosimov, A. N. Kuznetsov, A. A. Kuznetsova, O. N. Malyshev, A. G. Popeko, Yu. A. Popov, E. A. Sokol, M. L. Chelnokov, V. I. Chepigin, T. M. Schneidman, B. .. Gall, O. .. Dorvaux, P. .. Brione, A. .. Sellam, K. .. Hauschild, A. .. Lopez-Martenz, K. .. Rezynkina, S. .. Mullins, and P. .. Mosat
- Subjects
neutron multiplicity ,spontaneous fission ,fission fragment ,Physics ,QC1-999 - Abstract
In the last years we carried out several experiments aimed to investigate properties of short-lived SF isotopes. The neutron-deficient isotopes of nobelium were produced in fusion-evaporation reactions using206,208Pb targets and an intense48Ca-beam. Fusion-evaporation residues were separated by the SHELS separator and implanted into a large-area double-sided (48 × 48) strip silicon detector surrounded by3He-based neutron counters. Half-lives and decay branching ratios for252,254No isotopes were measured. The average number of neutrons per spontaneous fission of254No determined for the first time.
- Published
- 2021
- Full Text
- View/download PDF
22. Phase glides and self-organization of atomically abrupt interfaces out of stochastic disorder in $\alpha$-Ga$_{2}$O$_{3}$
- Author
-
Azarov, Alexander, Fernández, Javier García, Zhao, Junlei, He, Ru, Park, Ji-Hyeon, Jeon, Dae-Woo, Prytz, Øystein, Djurabekova, Flyura, and Kuznetsov, Andrej
- Subjects
Condensed Matter - Materials Science - Abstract
Disorder-induced ordering and unprecedentedly high radiation tolerance in $\gamma$-phase of gallium oxide is a recent spectacular discovery at the intersection of the fundamental physics and electronic applications. Importantly, by far, these data were collected with initial samples in form of the thermodynamically stable $\beta$-phase of this material. Here, we investigate these phenomena starting instead from already metastable $\alpha$-phase and explain radically new trend occurring in the system. We argue that in contrast to that in $\beta$-to-$\gamma$ disorder-induced transitions, the O sublattice in $\alpha$-phase exhibits hexagonal close-packed structure, so that to activate $\alpha$-to-$\gamma$ transformation significant structural rearrangements are required in both Ga and O sublattices. Moreover, consistently with theoretical predictions, $\alpha$-to-$\gamma$ phase transformation requires accumulation of the substantial tensile strain to initiate otherwise impossible lattice glides. Thus, we explain the experimentally observed trends in term of the combination of disorder and strain governing the process. Finally, and perhaps most amazingly, we demonstrate atomically abrupt $\alpha$/$\gamma$ interfaces paradoxically self-organized out of the stochastic disorder., Comment: 9 pages, 4 figures, under peer review
- Published
- 2024
23. Diagnostic Reasoning in Natural Language: Computational Model and Application
- Author
-
Dycke, Nils, Zečević, Matej, Kuznetsov, Ilia, Suess, Beatrix, Kersting, Kristian, and Gurevych, Iryna
- Subjects
Computer Science - Computation and Language - Abstract
Diagnostic reasoning is a key component of expert work in many domains. It is a hard, time-consuming activity that requires expertise, and AI research has investigated the ways automated systems can support this process. Yet, due to the complexity of natural language, the applications of AI for diagnostic reasoning to language-related tasks are lacking. To close this gap, we investigate diagnostic abductive reasoning (DAR) in the context of language-grounded tasks (NL-DAR). We propose a novel modeling framework for NL-DAR based on Pearl's structural causal models and instantiate it in a comprehensive study of scientific paper assessment in the biomedical domain. We use the resulting dataset to investigate the human decision-making process in NL-DAR and determine the potential of LLMs to support structured decision-making over text. Our framework, open resources and tools lay the groundwork for the empirical study of collaborative diagnostic reasoning in the age of LLMs, in the scholarly domain and beyond.
- Published
- 2024
24. Quadrics on Gushel-Mukai varieties
- Author
-
Debarre, Olivier and Kuznetsov, Alexander
- Subjects
Mathematics - Algebraic Geometry - Abstract
We study Hilbert schemes of quadrics of dimension $k \in \{0,1,2,3\}$ on smooth Gushel-Mukai varieties $X$ of dimension $n \in \{2,3,4,5,6\}$ by relating them to the relative Hilbert schemes of linear subspaces of dimension $k + 1$ of a certain family, naturally associated with $X$, of quadrics of dimension $n - 1$ over the blowup of $\mathbf{P}^5$ at a point., Comment: 65 pages
- Published
- 2024
25. HLogformer: A Hierarchical Transformer for Representing Log Data
- Author
-
Hou, Zhichao, Ghashami, Mina, Kuznetsov, Mikhail, and Torkamani, MohamadAli
- Subjects
Computer Science - Machine Learning ,Computer Science - Artificial Intelligence - Abstract
Transformers have gained widespread acclaim for their versatility in handling diverse data structures, yet their application to log data remains underexplored. Log data, characterized by its hierarchical, dictionary-like structure, poses unique challenges when processed using conventional transformer models. Traditional methods often rely on manually crafted templates for parsing logs, a process that is labor-intensive and lacks generalizability. Additionally, the linear treatment of log sequences by standard transformers neglects the rich, nested relationships within log entries, leading to suboptimal representations and excessive memory usage. To address these issues, we introduce HLogformer, a novel hierarchical transformer framework specifically designed for log data. HLogformer leverages the hierarchical structure of log entries to significantly reduce memory costs and enhance representation learning. Unlike traditional models that treat log data as flat sequences, our framework processes log entries in a manner that respects their inherent hierarchical organization. This approach ensures comprehensive encoding of both fine-grained details and broader contextual relationships. Our contributions are threefold: First, HLogformer is the first framework to design a dynamic hierarchical transformer tailored for dictionary-like log data. Second, it dramatically reduces memory costs associated with processing extensive log sequences. Third, comprehensive experiments demonstrate that HLogformer more effectively encodes hierarchical contextual information, proving to be highly effective for downstream tasks such as synthetic anomaly detection and product recommendation.
- Published
- 2024
26. Thermal Stoner-Wohlfarth Model for Magnetodynamics of Single Domain Nanoparticles: Implementation and Validation
- Author
-
Mostarac, Deniz, Kuznetsov, Andrey A., Helbig, Santiago, Abert, Claas, Sanchez, Pedro A., Suess, Dieter, and Kantorovich, Sofia S.
- Subjects
Physics - Computational Physics ,Condensed Matter - Soft Condensed Matter - Abstract
We present the thermal Stoner-Wohlfarth (tSW) model and apply it in the context of Molecular Dynamics simulations. The model is validated against an ensemble of immobilized, non-interacting, randomly oriented uniaxial particles (solid superparamagnet) and a classical dilute (non-interacting) ferrofluid for different combinations of anisotropy strength and magnetic field/moment coupling, at a fixed temperature. We compare analytical and simulation results to quantify the viability of the tSW model in reproducing the equilibrium and dynamic properties of magnetic soft matter systems. We show that if the anisotropy of a particle is more than four-five times higher than the thermal fluctuations, tSW is applicable and efficient. It provides a valuable insight into the interplay between internal magnetization degrees of freedom and Browninan rotation that is often neglected in the fixed point-dipole representation-based magnetic soft matter theoretical investigations.
- Published
- 2024
27. Photonuclear reactions on $^{59}$Co at bremsstrahlung end-point energies of 40-130 MeV
- Author
-
Rasulova, F. A., Belyshev, S. S., Demichev, M. A., Demin, D. L., Evseev, S. A., Fursova, N. Yu., Gostkin, M. I., Khushvaktov, J. H., Kobets, V. V., Kuznetsov, A. A., Rozov, S. V., Ruziev, E. T., Solnyshkin, A. A., Tran, T. N., Yakushev, E. A., and Yuldashev, B. S.
- Subjects
Nuclear Experiment ,Nuclear Theory - Abstract
Relative yields have been measured in the 40-130 MeV bremsstrahlung induced reactions of 59Co. The experiments have been performed with the beam from the electron linear accelerator LINAC-200 using the activation and off-line {\gamma}-ray spectrometric technique. The bremsstrahlung photon flux has been calculated with the Geant4 program. The cross sections were calculated by using computer code TALYS-1.96 with different models and are found to be in good agreement with the experimental data., Comment: 15 pages, 8 figures, 3 tables
- Published
- 2024
28. Asynchronous Latency and Fast Atomic Snapshot
- Author
-
Bezerra, João Paulo, Freitas, Luciano, and Kuznetsov, Petr
- Subjects
Computer Science - Distributed, Parallel, and Cluster Computing - Abstract
The original goal of this paper was a novel, fast atomic-snapshot protocol for asynchronous message-passing systems. In the process of defining what fast means exactly, we faced a number of interesting issues that arise when conventional time metrics are applied to asynchronous implementations. We discovered some gaps in latency claims made in earlier work on snapshot algorithms, which hampers their comparative time-complexity analysis. We then came up with a new unifying time-complexity analysis that captures the latency of an operation in an asynchronous, long-lived implementation, which allowed us to formally grasp latency improvements of our solution with respect to the state-of-the-art protocols: optimal latency in fault-free runs without contention, short constant latency in fault-free runs with contention, the worst-case latency proportional to the number of failures, and constant, close to optimal amortized latency.
- Published
- 2024
29. Spontaneous left coronary artery dissection in the postpartum period: a case report
- Author
-
A. A. Kuznetsov, A. M. Namitokov, A. V. Sazhneva, A. S. Nekrasov, and E. D. Kosmacheva
- Subjects
spontaneous coronary artery dissection ,acute coronary syndrome ,postpartum period ,case report ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Spontaneous coronary artery dissection is a rare disease that threatens the patient life. Often this pathology complicates the course of pregnancy or the postpartum period. The rare occurrence and difficulties in diagnosis are the reason for the lack of data and the impossibility of developing a single algorithm for diagnosing and treating spontaneous coronary artery dissection.The article provides a brief literature review and a case report of spontaneous coronary artery dissection in the postpartum period, and discusses a number of aspects of treatment tactics.
- Published
- 2022
- Full Text
- View/download PDF
30. Complex Characteristics of Yersinia pestis Strains Isolated in the Sarydzhaz and Upper-Naryn High-Mountain Foci in 2019–2020
- Author
-
L. M. Kukleva, A. K. Dzhaparova, E. G. Oglodin, E. A. Naryshkina, Ya. M. Krasnov, A. A. Kuznetsov, A. V. Fadeeva, G. A. Eroshenko, S. K. Berdiev, and V. V. Kutyrev
- Subjects
plague agent ,strains ,plague foci of the tien shan ,Infectious and parasitic diseases ,RC109-216 - Abstract
The aim of the study was a comprehensive analysis of the phenotypic and genetic properties of Yersinia pestis strains isolated in the Sarydzhaz and Upper-Naryn high-mountain foci of the Tien Shan in 2019–2020; determination of the present-day population structure and areal of these highly virulent strains of the plague pathogen.Materials and methods. Studies of biochemical properties (fermentation of carbohydrates, nutritional requirements), virulence (in vitro and in laboratory animals), molecular-genetic analysis and whole genome sequencing of Y. pestis strains isolated in the Sarydzhaz and Upper-Naryn high-mountain foci in 2019–2020 have been carried out. We used Y. pestis strains from the foci of the Tien Shan and Pamir-Alai dated 1928–2016 for the comparison. Whole genome sequencing was performed using the Ion S5 XL System. Phylogenetic analysis was performed on the basis of 1443 identified core SNPs in 36 Y. pestis strains of various phylogenetic lines included in the analysis. The construction of dendrograms was carried out using the Maximum Likelihood algorithm, PHYML program, HKY85 model.Results and discussion. It is established that all Y. pestis strains isolated in the Sarydzhaz and Upper-Naryn high-mountain foci in 2019–2020 belong to the 0.ANT5 phylogenetic branch of the ancient biovar of the main subspecies. Genome-wide sequencing revealed the presence of two 0.ANT5 clones, the first of which consists of strains from the basin of the river Kooylu in the Sarydzhaz focus, dated 2020. The second powerful clone includes the strains of 2012–2020 isolated in the Sarydzhaz and Upper-Naryn foci. The high virulence of the isolated strains has been shown. It was concluded that further study of the territories of the highmountain foci of the Tien Shan and Pamir-Alai is necessary to establish the current boundaries of the 0.ANT5 areal, as well as to identify the circulation areas of Y. pestis of other phylogenetic lineages.
- Published
- 2021
- Full Text
- View/download PDF
31. Epidemiological Situation on Plague in 2020. Forecast of Episootic Activity of Natural Plague Foci in the Russian Federation and Other CIS Countries for 2021
- Author
-
N. V. Popov, G. A. Eroshenko, I. G. Karnaukhov, A. A. Kuznetsov, A. N. Matrosov, A. V. Ivanova, E. G. Oglodin, K. A. Nikiforov, V. M. Korzun, D. B. Verzhutsky, E. V. Chipanin, T. Z. Ayazbaev, A. K. Dzhaparova, S. K. Berdiev, A. A. Lopatin, V. M. Dubyansky, S. A. Shcherbakova, S. V. Balakhonov, A. N. Kulichenko, and V. V. Kutyrev
- Subjects
natural foci of plague ,epizootic activity ,strains ,morbidity ,forecast ,preventive measures ,Infectious and parasitic diseases ,RC109-216 - Abstract
The aim of the work was to substantiate the forecast of the epidemiological and epizootiological situation in natural foci of plague in the Russian Federation, countries of the near and far abroad for the year of 2021. Characteristics of the distribution of Yersinia pestis strains of the main subspecies (subspecies pestis) of medieval and antique biovars, Caucasian (ssp. caucasica) and central Asian (ssp. central asiatica) subspecies by 45 natural foci of the CIS countries are presented in the paper. The persistence of a multidirectional trend in the dynamics of epizootic activity of natural foci of the CIS countries with the circulation of Y. pestis pestis strains of the medieval biovar of the 2.MED1 phylogenetic branch and the antique biovar of the 0.ANT5, 4.ANT phylogenetic branches in the current decade has been outlined. For the Russian Federation, the development of epizootics is predicted in the Gorno-Altai highland and Tuva mountain natural foci caused by the circulation of Y. pestis pestis strains of the antique biovar 4.ANT and Y. pestis of the Altai biovar of the Central Asian subspecies 0.PE4a in 2021. For the Republic of Kazakhstan, there is a high probability of preserving epizootic activity in the North Aral, Aral-Karakum, Balkhash, Mojynkum, Taukum desert and Ili intermountain natural foci with the circulation of Y. pestis pestis strains of the medieval biovar of the phylogenetic branch 2.MED1. For the Kyrgyz Republic, the forecast for the development of plague epizootics caused by Y. pestis pestis strains of the antique biovar 0.ANT5 phylogenetic branch in the Sarydzhaz and Upper Naryn high-mountain natural foci has been substantiated. A high epidemic risk of epizootic manifestations caused by highly virulent strains of Y. pestis pestis of antique biovars 0.ANT5, 4.ANT and medieval biovar 2.MED1 for the entire territory of the CIS countries is noted. The relevance of implementing forecasts of the epidemiological situation into practice, taking into account the molecular-genetic and epidemiological characteristics of Y. pestis strains circulating in areas of expected epizootic manifestations of plague, is highlighted.
- Published
- 2021
- Full Text
- View/download PDF
32. Results of surgical treatment on short-length bulbous urethral strictures
- Author
-
N. A. Goncharov, A. A. Kuznetsov, E. A. Morozov, and A. A. Kiseleva
- Subjects
urethral stricture ,internal optical urethrotomy (iout) ,anastomotic plastics «edge to edge» ,urethral plastics without spongious body incision ,Diseases of the genitourinary system. Urology ,RC870-923 - Abstract
Introduction. Urethral stricture disease is one of the most actual problems of modern urology, and the number of this pathology in the population increases year to year. To date, a large number of surgical methods for treating urethral strictures have been proposed. This study represents our experience in the surgical treatment of short-length bulbous urethral strictures.Purpose of the study. To analyze the results of surgical treatment of patients with short-length bulbous urethral strictures.Materials and methods. A retrospective analysis of the surgical treatment results in 75 patients with short-length bulbous urethral strictures was carried out. Treatment was carried out using various techniques: internal optical urethrotomy (IOUT), anastomotic urethral plasty, urethral plasty without crossing the spongy body. The effectiveness of the applied methods is assessed. The standard questionnaire I-PSS (International Prostate Symptom Score) was used to assess the quality of life of patients in all cases, which was filled out before surgery and 6 months after surgery.Results. The easiest and fastest to perform is the IOUT technique, but it has a high percentage of relapses — up to 76,47% in a follow-up. However, the number of recurrences when performing open surgical techniques, such as urethral plastic surgery without crossing the spongy body, anastomotic urethral plastic surgery, did not exceed 7.14% and 7.4%, respectively. Before surgery average IPSS score in patients who were carried out of IUOT, anastomotic plastic and plastic without crossing a spongy body, respectively 20,65 ± 0,62, 21,52 ± 0,64 and of 23,07 ± 0,76 points, and 6 months after surgical treatment the average score was 8,24 ± 0,63, 4,37 ± 0,33, 5,64 ± 0,37 points.Conclusions. It was revealed that currently, the most prognostically favourable methods of surgical treatment of urethral stricture disease are anastomotic urethral plasty, urethral plasty without crossing the spongy body.
- Published
- 2021
- Full Text
- View/download PDF
33. Determination of chemical composition on internal surfaces of hollow reinforced concrete structures under the influence of corrosion
- Author
-
A. S. Bryukhova, N. V. Volkova, A. Yu. Kuzmenko, and A. A. Kuznetsov
- Subjects
reinforced concrete structures ,corrosion defects ,surface ,laser spectrometry ,concrete sample ,laser analyzer ,instrument sensitivity ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
The paper presents the results of experimental studies on the determination of corrosion products on the surface of reinforced concrete structures. Methods for creating samples with artificial electrocorrosion under conditions close to real operation are discussed. The results of testing samples with different degrees of corrosion using laser-spark emission spectrometry (LIBS) devices are presented. The test is carried out on two different devices, a LIBS setup and a portable American-made laser analyzer LIBZ-300pe.
- Published
- 2020
- Full Text
- View/download PDF
34. Association of indicators of arterial rigidity and arrithmogenesis in Novosibirsk men population
- Author
-
A. A. Kuznetsov, E. E. Tsvetkova, A. A. Kuznetsova, V. N. Maximov, D. V. Denisova, and M. I. Voevoda
- Subjects
arterial stiffness ,pulse wave amplification ,pulse wave augmentation ,brugada pattern ,early repolarization ,qrs fragmentation ,Diseases of the blood and blood-forming organs ,RC633-647.5 ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Pulse wave amplification and augmentation are considered as new indicators of arterial stiffness. It is of interest to study their association with electrocardiographic pro-arrhythmic patterns in the male population of Novosibirsk. Material and methods. We used data from a representative sample of 145 men aged 25-44 years from a population of inhabitants of Novosibirsk. Applanation tonometry of the radial artery and pulse wave analysis were performed using the SphygmoCor system (AtCorMedical, Australia). The Brugada pattern, the pattern of early ventricular repolarization and fragmentation of the QRS complex were determined on a resting electrocardiogram according to generally accepted current criteria. When analyzing the data, descriptive statistics methods and the general linear model (GLM) were used. Results. Fragmentation of the QRS complex in the in the area of the inferior wall of the left ventricle, regardless of age, body mass index and heart rate, was associated with a decrease in the ratio of amplification of pulse pressure (F = 5.34; p = 0.022), amplification of pulse pressure (F = 5.91; p = 0.016) and amplification of systolic pressure (F = 5.02; p = 0.027). Conclusion. In the Novosibirsk male population, a decrease in pulse wave amplification was associated with fragmentation of the QRS complex. The results of this study demonstrate the relevance of an integrated assessment of prognostically significant indicators of arterial stiffness and ventricular pro-arrhythmia to study the possible cumulation of cardiovascular risk.
- Published
- 2020
- Full Text
- View/download PDF
35. Symmetry-breaking of turbulent flow due to asymmetric vortex shedding in periodic porous media
- Author
-
Srikanth, Vishal and Kuznetsov, Andrey V.
- Subjects
Physics - Fluid Dynamics - Abstract
In this paper, we report new insight into a symmetry-breaking phenomenon that occurs for turbulent flow in periodic porous media composed of cylindrical solid obstacles with circular cross-section. We have used Large Eddy Simulation to investigate the symmetry-breaking phenomenon by varying the porosity (0.57-0.99) and the pore scale Reynolds number (37-1,000). Asymmetrical flow distribution is observed in the intermediate porosity flow regime for values of porosities between 0.8 and 0.9, which is characterized by the formation of alternating low and high velocity flow channels above and below the solid obstacles. These channels are parallel to the direction of the flow. Correspondingly, the microscale vortices formed behind the solid obstacles exhibit a bias in the shedding direction. The transition from symmetric to asymmetric flow occurs in between the Reynolds numbers of 37 (laminar) and 100 (turbulent). A Hopf bifurcation resulting in unsteady oscillatory laminar flow marks the origin of a secondary flow instability arising from the interaction of the shear layers around the solid obstacle. When turbulence emerges, stochastic phase difference in the vortex wake oscillations caused by the secondary flow instability results in flow symmetry breaking. We note that symmetry breaking does not occur for cylindrical solid obstacles with square cross-section due to the presence of sharp vertices in the solid obstacle surface. At the macroscale level, symmetry-breaking results in residual transverse drag force components acting on the solid obstacle surfaces. Symmetry-breaking promotes attached flow on the solid obstacle surface, which is potentially beneficial for improving transport properties at the solid obstacle surface such as convection heat flux., Comment: 19 pages, 10 figures
- Published
- 2024
36. Using recurrent neural networks to predict aspects of 3-D structure of folded copolymer sequences
- Author
-
Reilly, R. G., Kechadi, M. -T., Kuznetsov, Yu. A., Timoshenko, E. G., and Dawson, K. A.
- Subjects
Condensed Matter - Soft Condensed Matter ,Condensed Matter - Disordered Systems and Neural Networks ,Condensed Matter - Statistical Mechanics ,Physics - Computational Physics - Abstract
The neural network techniques are developed for artificial sequences based on approximate models of proteins. We only encode the hydrophobicity of the amino acid side chains without attempting to model the secondary structure. We use our approach to obtain a large set of sequences with known 3-D structures for training the neural network. By employing recurrent neural networks we describe a way to augment a neural network to deal with sequences of realistic length and long-distant interactions between the sequence regions., Comment: 10 pages, 4 postscript figures
- Published
- 2024
37. Three-Dimensional Acoustic Turbulence: Weak Versus Strong
- Author
-
Kochurin, E. A. and Kuznetsov, E. A.
- Subjects
Nonlinear Sciences - Chaotic Dynamics - Abstract
Direct numerical simulation of three-dimensional acoustic turbulence has been performed for both weak and strong regimes. Within the weak turbulence, we demonstrate the existence of the Zakharov-Sagdeev spectrum $\propto k^{-3/2}$ not only for weak dispersion but in the non-dispersion (ND) case as well. Such spectra in the $k$-space are accompanied by jets in the form of narrow cones. These distributions are realized due to small nonlinearity compared with both dispersion/diffraction. Increasing pumping in the ND case due to dominant nonlinear effects leads to the formation of shocks. As a result, the acoustic turbulence turns into an ensemble of random shocks with the Kadomtsev-Petviashvili spectrum., Comment: 11 pages, 7 figures
- Published
- 2024
38. Systematic Task Exploration with LLMs: A Study in Citation Text Generation
- Author
-
Şahinuç, Furkan, Kuznetsov, Ilia, Hou, Yufang, and Gurevych, Iryna
- Subjects
Computer Science - Computation and Language - Abstract
Large language models (LLMs) bring unprecedented flexibility in defining and executing complex, creative natural language generation (NLG) tasks. Yet, this flexibility brings new challenges, as it introduces new degrees of freedom in formulating the task inputs and instructions and in evaluating model performance. To facilitate the exploration of creative NLG tasks, we propose a three-component research framework that consists of systematic input manipulation, reference data, and output measurement. We use this framework to explore citation text generation -- a popular scholarly NLP task that lacks consensus on the task definition and evaluation metric and has not yet been tackled within the LLM paradigm. Our results highlight the importance of systematically investigating both task instruction and input configuration when prompting LLMs, and reveal non-trivial relationships between different evaluation metrics used for citation text generation. Additional human generation and human evaluation experiments provide new qualitative insights into the task to guide future research in citation text generation. We make our code and data publicly available., Comment: Accepted to ACL 2024 (Main)
- Published
- 2024
39. ESQA: Event Sequences Question Answering
- Author
-
Abdullaeva, Irina, Filatov, Andrei, Orlov, Mikhail, Karpukhin, Ivan, Vasilev, Viacheslav, Dimitrov, Denis, Kuznetsov, Andrey, Kireev, Ivan, and Savchenko, Andrey
- Subjects
Computer Science - Computation and Language ,Computer Science - Machine Learning - Abstract
Event sequences (ESs) arise in many practical domains including finance, retail, social networks, and healthcare. In the context of machine learning, event sequences can be seen as a special type of tabular data with annotated timestamps. Despite the importance of ESs modeling and analysis, little effort was made in adapting large language models (LLMs) to the ESs domain. In this paper, we highlight the common difficulties of ESs processing and propose a novel solution capable of solving multiple downstream tasks with little or no finetuning. In particular, we solve the problem of working with long sequences and improve time and numeric features processing. The resulting method, called ESQA, effectively utilizes the power of LLMs and, according to extensive experiments, achieves state-of-the-art results in the ESs domain., Comment: 25 pages, 3 figures
- Published
- 2024
40. M2QA: Multi-domain Multilingual Question Answering
- Author
-
Engländer, Leon, Sterz, Hannah, Poth, Clifton, Pfeiffer, Jonas, Kuznetsov, Ilia, and Gurevych, Iryna
- Subjects
Computer Science - Computation and Language - Abstract
Generalization and robustness to input variation are core desiderata of machine learning research. Language varies along several axes, most importantly, language instance (e.g. French) and domain (e.g. news). While adapting NLP models to new languages within a single domain, or to new domains within a single language, is widely studied, research in joint adaptation is hampered by the lack of evaluation datasets. This prevents the transfer of NLP systems from well-resourced languages and domains to non-dominant language-domain combinations. To address this gap, we introduce M2QA, a multi-domain multilingual question answering benchmark. M2QA includes 13,500 SQuAD 2.0-style question-answer instances in German, Turkish, and Chinese for the domains of product reviews, news, and creative writing. We use M2QA to explore cross-lingual cross-domain performance of fine-tuned models and state-of-the-art LLMs and investigate modular approaches to domain and language adaptation. We witness 1) considerable performance variations across domain-language combinations within model classes and 2) considerable performance drops between source and target language-domain combinations across all model sizes. We demonstrate that M2QA is far from solved, and new methods to effectively transfer both linguistic and domain-specific information are necessary. We make M2QA publicly available at https://github.com/UKPLab/m2qa.
- Published
- 2024
41. Image-GS: Content-Adaptive Image Representation via 2D Gaussians
- Author
-
Zhang, Yunxiang, Kuznetsov, Alexandr, Jindal, Akshay, Chen, Kenneth, Sochenov, Anton, Kaplanyan, Anton, and Sun, Qi
- Subjects
Computer Science - Computer Vision and Pattern Recognition ,Computer Science - Graphics - Abstract
Neural image representations have recently emerged as a promising technique for storing, streaming, and rendering visual data. Coupled with learning-based workflows, these novel representations have demonstrated remarkable visual fidelity and memory efficiency. However, existing neural image representations often rely on explicit uniform data structures without content adaptivity or computation-intensive implicit models, limiting their adoption in real-time graphics applications. Inspired by recent advances in radiance field rendering, we propose Image-GS, a content-adaptive image representation. Using anisotropic 2D Gaussians as the basis, Image-GS shows high memory efficiency, supports fast random access, and offers a natural level of detail stack. Leveraging a tailored differentiable renderer, Image-GS fits a target image by adaptively allocating and progressively optimizing a set of 2D Gaussians. The generalizable efficiency and fidelity of Image-GS are validated against several recent neural image representations and industry-standard texture compressors on a diverse set of images. Notably, its memory and computation requirements solely depend on and linearly scale with the number of 2D Gaussians, providing flexible controls over the trade-off between visual fidelity and run-time efficiency. We hope this research offers insights for developing new applications that require adaptive quality and resource control, such as machine perception, asset streaming, and content generation.
- Published
- 2024
42. Integrated Triply Resonant Electro-Optic Frequency Comb in Lithium Tantalate
- Author
-
Zhang, Junyin, Wang, Chengli, Denney, Connor, Lihachev, Grigory, Hu, Jianqi, Kao, Wil, Blésin, Terence, Kuznetsov, Nikolai, Li, Zihan, Churaev, Mikhail, Ou, Xin, Riemensberger, Johann, Santamaria-Botello, Gabriel, and Kippenberg, Tobias J.
- Subjects
Physics - Optics - Abstract
Integrated frequency comb generators based on Kerr parametric oscillation have led to chip-scale, gigahertz-spaced combs with new applications spanning hyperscale telecommunications, low-noise microwave synthesis, LiDAR, and astrophysical spectrometer calibration. Recent progress in lithium niobate (LN) photonic integrated circuits (PICs) has resulted in chip-scale electro-optic (EO) frequency combs, offering precise comb-line positioning and simple operation without relying on the formation of dissipative Kerr solitons. However, current integrated EO combs face limited spectral coverage due to the large microwave power required to drive the non-resonant capacitive electrodes and the strong intrinsic birefringence of Lithium Niobate. Here, we overcome both challenges with an integrated triply resonant architecture, combining monolithic microwave integrated circuits (MMICs) with PICs based on the recently emerged thin-film lithium tantalate. With resonantly enhanced EO interaction and reduced birefringence in Lithium Tantalate, we achieve a four-fold comb span extension and a 16-fold power reduction compared to the conventional non-resonant microwave design. Driven by a hybrid-integrated laser diode, the comb spans over 450nm (60THz) with >2000 lines, and the generator fits within a compact 1cm^2 footprint. We additionally observe that the strong EO coupling leads to an increased comb existence range approaching the full free spectral range of the optical microresonator. The ultra-broadband comb generator, combined with detuning-agnostic operation, could advance chip-scale spectrometry and ultra-low-noise millimeter wave synthesis and unlock octave-spanning EO combs. The methodology of co-designing microwave and optical resonators can be extended to a wide range of integrated electro-optics applications., Comment: Main text: 9 pages; SI: 20 pages; v2: Funding information correction; v3: Acknowledgement update
- Published
- 2024
43. Isotropy of cosmic rays beyond $10^{20}$ eV favors their heavy mass composition
- Author
-
Telescope Array Collaboration, Abbasi, R. U., Abe, Y., Abu-Zayyad, T., Allen, M., Arai, Y., Arimura, R., Barcikowski, E., Belz, J. W., Bergman, D. R., Blake, S. A., Buckland, I., Cheon, B. G., Chikawa, M., Fujii, T., Fujisue, K., Fujita, K., Fujiwara, R., Fukushima, M., Furlich, G., Globus, N., Gonzalez, R., Hanlon, W., Hayashida, N., He, H., Hibi, R., Hibino, K., Higuchi, R., Honda, K., Ikeda, D., Inoue, N., Ishii, T., Ito, H., Ivanov, D., Iwasaki, A., Jeong, H. M., Jeong, S., Jui, C. C. H., Kadota, K., Kakimoto, F., Kalashev, O., Kasahara, K., Kasami, S., Kawakami, S., Kawata, K., Kharuk, I., Kido, E., Kim, H. B., Kim, J. H., Kim, S. W., Kimura, Y., Komae, I., Kuzmin, V., Kuznetsov, M., Kwon, Y. J., Lee, K. H., Lubsandorzhiev, B., Lundquist, J. P., Matsumiya, H., Matsuyama, T., Matthews, J. N., Mayta, R., Mizuno, K., Murakami, M., Myers, I., Nagataki, S., Nakai, K., Nakamura, T., Nishio, E., Nonaka, T., Oda, H., Ogio, S., Onishi, M., Ohoka, H., Okazaki, N., Oku, Y., Okuda, T., Omura, Y., Ono, M., Oshima, A., Oshima, H., Ozawa, S., Park, I. H., Park, K. Y., Potts, M., Pshirkov, M. S., Remington, J., Rodriguez, D. C., Rott, C., Rubtsov, G. I., Ryu, D., Sagawa, H., Saito, R., Sakaki, N., Sako, T., Sakurai, N., Sato, D., Sato, K., Sato, S., Sekino, K., Shah, P. D., Shibata, N., Shibata, T., Shikita, J., Shimodaira, H., Shin, B. K., Shin, H. S., Shinto, D., Smith, J. D., Sokolsky, P., Stokes, B. T., Stroman, T. A., Takagi, Y., Takahashi, K., Takamura, M., Takeda, M., Takeishi, R., Taketa, A., Takita, M., Tameda, Y., Tanaka, K., Tanaka, M., Tanoue, Y., Thomas, S. B., Thomson, G. B., Tinyakov, P., Tkachev, I., Tokuno, H., Tomida, T., Troitsky, S., Tsuda, R., Tsunesada, Y., Udo, S., Urban, F., Warren, D., Wong, T., Yamazaki, K., Yashiro, K., Yoshida, F., Zhezher, Y., and Zundel, Z.
- Subjects
Astrophysics - High Energy Astrophysical Phenomena - Abstract
We report an estimation of the injected mass composition of ultra-high energy cosmic rays (UHECRs) at energies higher than 10 EeV. The composition is inferred from an energy-dependent sky distribution of UHECR events observed by the Telescope Array surface detector by comparing it to the Large Scale Structure of the local Universe. In the case of negligible extra-galactic magnetic fields the results are consistent with a relatively heavy injected composition at E ~ 10 EeV that becomes lighter up to E ~ 100 EeV, while the composition at E > 100 EeV is very heavy. The latter is true even in the presence of highest experimentally allowed extra-galactic magnetic fields, while the composition at lower energies can be light if a strong EGMF is present. The effect of the uncertainty in the galactic magnetic field on these results is subdominant., Comment: 8 pages, 3 figures, accepted for publication in PRL
- Published
- 2024
44. Mass composition of ultra-high energy cosmic rays from distribution of their arrival directions with the Telescope Array
- Author
-
Telescope Array Collaboration, Abbasi, R. U., Abe, Y., Abu-Zayyad, T., Allen, M., Arai, Y., Arimura, R., Barcikowski, E., Belz, J. W., Bergman, D. R., Blake, S. A., Buckland, I., Cheon, B. G., Chikawa, M., Fujii, T., Fujisue, K., Fujita, K., Fujiwara, R., Fukushima, M., Furlich, G., Globus, N., Gonzalez, R., Hanlon, W., Hayashida, N., He, H., Hibi, R., Hibino, K., Higuchi, R., Honda, K., Ikeda, D., Inoue, N., Ishii, T., Ito, H., Ivanov, D., Iwasaki, A., Jeong, H. M., Jeong, S., Jui, C. C. H., Kadota, K., Kakimoto, F., Kalashev, O., Kasahara, K., Kasami, S., Kawakami, S., Kawata, K., Kharuk, I., Kido, E., Kim, H. B., Kim, J. H., Kim, S. W., Kimura, Y., Komae, I., Kuzmin, V., Kuznetsov, M., Kwon, Y. J., Lee, K. H., Lubsandorzhiev, B., Lundquist, J. P., Matsumiya, H., Matsuyama, T., Matthews, J. N., Mayta, R., Mizuno, K., Murakami, M., Myers, I., Nagataki, S., Nakai, K., Nakamura, T., Nishio, E., Nonaka, T., Oda, H., Ogio, S., Onishi, M., Ohoka, H., Okazaki, N., Oku, Y., Okuda, T., Omura, Y., Ono, M., Oshima, A., Oshima, H., Ozawa, S., Park, I. H., Park, K. Y., Potts, M., Pshirkov, M. S., Remington, J., Rodriguez, D. C., Rott, C., Rubtsov, G. I., Ryu, D., Sagawa, H., Saito, R., Sakaki, N., Sako, T., Sakurai, N., Sato, D., Sato, K., Sato, S., Sekino, K., Shah, P. D., Shibata, N., Shibata, T., Shikita, J., Shimodaira, H., Shin, B. K., Shin, H. S., Shinto, D., Smith, J. D., Sokolsky, P., Stokes, B. T., Stroman, T. A., Takagi, Y., Takahashi, K., Takamura, M., Takeda, M., Takeishi, R., Taketa, A., Takita, M., Tameda, Y., Tanaka, K., Tanaka, M., Tanoue, Y., Thomas, S. B., Thomson, G. B., Tinyakov, P., Tkachev, I., Tokuno, H., Tomida, T., Troitsky, S., Tsuda, R., Tsunesada, Y., Udo, S., Urban, F., Warren, D., Wong, T., Yamazaki, K., Yashiro, K., Yoshida, F., Zhezher, Y., and Zundel, Z.
- Subjects
Astrophysics - High Energy Astrophysical Phenomena - Abstract
We use a new method to estimate the injected mass composition of ultrahigh cosmic rays (UHECRs) at energies higher than 10 EeV. The method is based on comparison of the energy-dependent distribution of cosmic ray arrival directions as measured by the Telescope Array experiment (TA) with that calculated in a given putative model of UHECR under the assumption that sources trace the large-scale structure (LSS) of the Universe. As we report in the companion letter, the TA data show large deflections with respect to the LSS which can be explained, assuming small extra-galactic magnetic fields (EGMF), by an intermediate composition changing to a heavy one (iron) in the highest energy bin. Here we show that these results are robust to uncertainties in UHECR injection spectra, the energy scale of the experiment and galactic magnetic fields (GMF). The assumption of weak EGMF, however, strongly affects this interpretation at all but the highest energies E > 100 EeV, where the remarkable isotropy of the data implies a heavy injected composition even in the case of strong EGMF. This result also holds if UHECR sources are as rare as $2 \times 10^{-5}$ Mpc$^{-3}$, that is the conservative lower limit for the source number density., Comment: 18 pages, 11 figures, accepted for publication in PRD
- Published
- 2024
45. The EUSO-SPB2 Fluorescence Telescope for the Detection of Ultra-High Energy Cosmic Rays
- Author
-
Adams Jr., James H., Allard, Denis, Alldredge, Phillip, Anchordoqui, Luis, Anzalone, Anna, Battisti, Matteo, Belov, Alexander A., Bertaina, Mario, Bertone, Peter F., Blin-Bondil, Sylvie, Burton, Julia, Cafagna, Francesco S., Casolino, Marco, Černý, Karel, Christ, Mark J., Colalillo, Roberta, Crawford, Hank J., Creusot, Alexandre, Cummings, Austin, Diesing, Rebecca, Di Nola, Alessandro, Ebisuzaki, Toshikazu, Eser, Johannes, Ferrarese, Silvia, Filippatos, George, Finch, William W., Flaminio, Flavia, Fornaro, Claudio, Fuehne, Duncan, Fuglesang, Christer, Garg, Diksha, Golzio, Alessio, Guarino, Fausto, Guépin, Claire, Heibges, Tobias, Judd, Eleanor G., Klimov, Pavel A., Krizmanic, John F., Kungel, Viktoria, Kupari, Luke, Kuznetsov, Evgeny, Manfrin, Massimiliano, Marszal, Wlodzimierz, Matthews, John N., Mese, Marco, Meyer, Stephan S., Mignone, Marco, Miyamoto, Hiroko, Murashov, Alexey S., Nachtman, Jane M., Olinto, Angela V., Onel, Yasar, Osteria, Giuseppe, Panico, Beatrice, Parizot, Ètienne, Paul, Tom, Pech, Miroslav, Perfetto, Francesco, Piotrowski, Lech W., Plebaniak, Zbigniew, Posligua, Jonatan, Prévôt, Guillaume, Przybylak, Marika, Reardon, Patrick, Reno, Mary Hall, Ricci, Marco, Sarazin, Fred, Schovánek, P., Scotti, Valentina, Shinozaki, Kenji, Soriano, Jorge F., Stillwell, Ben K., Szabelski, Jacek, Takizawa, Yoshiyuki, Trofimov, Daniil, Unel, Fredrik, Valore, Laura, Venters, Tonia M., Watts Jr., John, Wiencke, Lawrence, Wistrand, Hannah, and Young, Roy
- Subjects
Astrophysics - Instrumentation and Methods for Astrophysics ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
The Extreme Universe Space Observatory on a Super Pressure Balloon 2 (EUSO-SPB2) flew on May 13$^{\text{th}}$ and 14$^{\text{th}}$ of 2023. Consisting of two novel optical telescopes, the payload utilized next-generation instrumentation for the observations of extensive air showers from near space. One instrument, the fluorescence telescope (FT) searched for Ultra-High Energy Cosmic Rays (UHECRs) by recording the atmosphere below the balloon in the near-UV with a 1~$\mu$s time resolution using 108 multi-anode photomultiplier tubes with a total of 6,912 channels. Validated by pre-flight measurements during a field campaign, the energy threshold was estimated around 2~EeV with an expected event rate of approximately 1 event per 10 hours of observation. Based on the limited time afloat, the expected number of UHECR observations throughout the flight is between 0 and 2. Consistent with this expectation, no UHECR candidate events have been found. The majority of events appear to be detector artifacts that were not rejected properly due to a shortened commissioning phase. Despite the earlier-than-expected termination of the flight, data were recorded which provide insights into the detectors stability in the near-space environment as well as the diffuse ultraviolet emissivity of the atmosphere, both of which are impactful to future experiments.
- Published
- 2024
- Full Text
- View/download PDF
46. Observation of Declination Dependence in the Cosmic Ray Energy Spectrum
- Author
-
The Telescope Array Collaboration, Abbasi, R. U., Abu-Zayyad, T., Allen, M., Belz, J. W., Bergman, D. R., Buckland, I., Campbell, W., Cheon, B. G., Endo, K., Fedynitch, A., Fujii, T., Fujisue, K., Fujita, K., Fukushima, M., Furlich, G., Gerber, Z., Globus, N., Hanlon, W., Hayashida, N., He, H., Hibino, K., Higuchi, R., Ikeda, D., Ishii, T., Ivanov, D., Jeong, S., Jui, C. C. H., Kadota, K., Kakimoto, F., Kalashev, O., Kasahara, K., Kawachi, Y., Kawata, K., Kharuk, I., Kido, E., Kim, H. B., Kim, J. H., Kim, S. W., Kobo, R., Komae, I., Komatsu, K., Komori, K., Koyama, C., Kudenko, M., Kuroiwa, M., Kusumori, Y., Kuznetsov, M., Kwon, Y. J., Lee, K. H., Lee, M. J., Lubsandorzhiev, B., Lundquist, J. P., Matsuzawa, A., Matthews, J. A., Matthews, J. N., Mizuno, K., Mori, M., Murakami, M., Nagataki, S., Nakahara, M., Nakamura, T., Nakayama, T., Nakayama, Y., Nonaka, T., Ogio, S., Ohoka, H., Okazaki, N., Onishi, M., Oshima, A., Oshima, H., Ozawa, S., Park, I. H., Park, K. Y., Potts, M., Przybylak, M., Pshirkov, M. S., Remington, J., Rott, C., Rubtsov, G. I., Ryu, D., Sagawa, H., Sakaki, N., Sakamoto, R., Sako, T., Sakurai, N., Sakurai, S., Sato, D., Sato, S., Sekino, K., Shibata, T., Shikita, J., Shimodaira, H., Shin, B. K., Shin, H. S., Shinozaki, K., Smith, J. D., Sokolsky, P., Stokes, B. T., Stroman, T. A., Takagi, Y., Takahashi, K., Takeda, M., Takeishi, R., Taketa, A., Takita, M., Tameda, Y., Tanaka, K., Tanaka, M., Thomas, S. B., Thomson, G. B., Tinyakov, P., Tkachev, I., Tomida, T., Troitsky, S., Tsunesada, Y., Udo, S., Urban, F., Vaiman, I. A., Vrábel, M., Warren, D., Yamazaki, K., Zhezher, Y., Zundel, Z., and Zvirzdin, J.
- Subjects
Astrophysics - High Energy Astrophysical Phenomena - Abstract
We report on an observation of the difference between northern and southern skies of the ultrahigh energy cosmic ray energy spectrum with a significance of ${\sim}8\sigma$. We use measurements from the two largest experiments$\unicode{x2014}$the Telescope Array observing the northern hemisphere and the Pierre Auger Observatory viewing the southern hemisphere. Since the comparison of two measurements from different observatories introduces the issue of possible systematic differences between detectors and analyses, we validate the methodology of the comparison by examining the region of the sky where the apertures of the two observatories overlap. Although the spectra differ in this region, we find that there is only a $1.8\sigma$ difference between the spectrum measurements when anisotropic regions are removed and a fiducial cut in the aperture is applied., Comment: 8 pages, 6 figures
- Published
- 2024
47. The Camera and Readout for the Trinity Demonstrator and the EUSO-SPB2 Cherenkov Telescope
- Author
-
Bagheri, Mahdi, Gadamsetty, Srikar, Gazda, Eliza, Judd, Eleanor, Kuznetsov, Evgeny, Otte, A. Nepomuk, Potts, Mathew, Matamala, Oscar Romero, Shapera, Noah, Sorell, Joshua, Tandon, Svanik, and Wang, Andrew
- Subjects
Astrophysics - Instrumentation and Methods for Astrophysics ,Astrophysics - High Energy Astrophysical Phenomena ,High Energy Physics - Experiment ,Physics - Instrumentation and Detectors - Abstract
We developed a modular silicon photomultiplier camera to detect Earth-skimming PeV to EeV tau neutrinos with the imaging atmospheric Cherenkov technique. We built two cameras, a 256-pixel camera with S14161-6050HS SiPMs for the Trinity Demonstrator located on Frisco Peak, Utah, and a 512-pixel camera with S14521-6050AN SiPMs for the EUSO-SPB2 Cherenkov Telescope. The front-end electronics are based on the eMUSIC ASIC, and the camera signals are sampled and digitized with the 100MS/s and 12-bit AGET system. Both cameras are liquid-cooled. We detail the camera concept and the results from characterizing the SiPMs, bench testing, and calibrating the two cameras., Comment: Submitted to Nuclear Instruments and Methods in Physics Research A
- Published
- 2024
48. Thin Film Reconfigurable Intelligent Surface for Harmonic Beam Steering
- Author
-
Xie, Boxuan, Kuznetsov, Aleksandr D., Mela, Lauri, Lietzén, Jari, Ruttik, Kalle, Karakoç, Alp, and Jäntti, Riku
- Subjects
Electrical Engineering and Systems Science - Signal Processing ,Electrical Engineering and Systems Science - Systems and Control - Abstract
This letter explores an implementation of a novel thin film 1-by-4 reconfigurable intelligent surface (RIS) designed for future communication and sensing scenarios. Utilizing cost-effective inkjet printing methods and additive manufacturing, our approach significantly simplifies the RIS construction process and reduces production costs. The RIS, fabricated on a flexible and lightweight polyethylene terephthalate (PET) substrate, integrates antennas, switching circuitry, and a microcontroller unit (MCU), without a ground shield. This setup enables individual and simultaneous control of each RIS element, manipulating the captured carrier signal by reflecting and refracting its dominant harmonics. Beams of the harmonics can be steered to multiple desired directions at both front and back sides of the surface. Measurement results of the beam steering show that the RIS has the potential to enable RIS-aided communication and sensing applications., Comment: 5 pages, 4 figures, IEEE letter
- Published
- 2024
- Full Text
- View/download PDF
49. Thermal Conductivity of Double Polymorph Ga2O3 Structures
- Author
-
Abdullaev, Azat, Sekerbayev, Kairolla, Azarov, Alexander, Venkatachalapathy, Vishnukanthan, Chauhan, Vinay S., Utegulov, Zhandos, and Kuznetsov, Andrej
- Subjects
Condensed Matter - Materials Science - Abstract
Recently discovered double gamma/beta ({\gamma}/\b{eta}) polymorph Ga2O3 structures constitute a class of novel materials providing an option to modulate functional properties across interfaces without changing chemical compositions of materials, in contrast to that in conventional heterostructures. In this work, for the first time, we investigate thermal transport in such homo-interface structures as an example of their physical properties. Specifically, the cross-plane thermal conductivity (k) was measured by femtosecond laser-based time-domain thermoreflectance with MHz modulation rates, effectively obtaining depth profiles of the thermal conductivity across the {\gamma}/\b{eta}-Ga2O3 structures. In this way, the thermal conductivity of {\gamma}-Ga2O3 k=1.84{\div}2.11 W m-1K-1 was found to be independent of the initial \b{eta}-substrates orientations, in accordance with the cubic spinel structure of the {\gamma}-phase and consistently with the molecular dynamics simulation data. In its turn, the thermal conductivity of monoclinic \b{eta}-Ga2O3 showed a distinct anisotropy, with values ranging from 10 W m-1K-1 for [201] to 20 Wm-1K-1 for [010] orientations. Thus, for double {\gamma}/\b{eta} Ga2O3 polymorph structures formed on [010] \b{eta}-substrates, there is an order of magnitude difference in thermal conductivity across the {\gamma}/\b{eta} interface, which potentially can be exploited in thermal energy conversion applications.
- Published
- 2024
50. BindGPT: A Scalable Framework for 3D Molecular Design via Language Modeling and Reinforcement Learning
- Author
-
Zholus, Artem, Kuznetsov, Maksim, Schutski, Roman, Shayakhmetov, Rim, Polykovskiy, Daniil, Chandar, Sarath, and Zhavoronkov, Alex
- Subjects
Computer Science - Machine Learning - Abstract
Generating novel active molecules for a given protein is an extremely challenging task for generative models that requires an understanding of the complex physical interactions between the molecule and its environment. In this paper, we present a novel generative model, BindGPT which uses a conceptually simple but powerful approach to create 3D molecules within the protein's binding site. Our model produces molecular graphs and conformations jointly, eliminating the need for an extra graph reconstruction step. We pretrain BindGPT on a large-scale dataset and fine-tune it with reinforcement learning using scores from external simulation software. We demonstrate how a single pretrained language model can serve at the same time as a 3D molecular generative model, conformer generator conditioned on the molecular graph, and a pocket-conditioned 3D molecule generator. Notably, the model does not make any representational equivariance assumptions about the domain of generation. We show how such simple conceptual approach combined with pretraining and scaling can perform on par or better than the current best specialized diffusion models, language models, and graph neural networks while being two orders of magnitude cheaper to sample.
- Published
- 2024
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.