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High-speed performance self-powered short wave ultraviolet radiation detectors based onκ(ε)-Ga_(2)O_(3)

Journal of Semiconductors 2024年第4期45卷 56-62页

作者： Aleksei Almaev alexander Tsymbalov Bogdan Kushnarev Vladimir Nikolaev Alexei Pechnikov Mikhail Scheglov Andrei Chikiryaka Petr Korusenko Research and Development Center for Advanced Technologies in Microelectronics National Research Tomsk State UniversityTomsk 634050Russia Fokon LLC Kaluga 248035Russia Department of Semiconductor Electronics and Physics of Semiconductors National University of Science and Technology MISISMoscow 119049Russia Perfect Crystals LLC Saint Petersburg 194223Russia Department of Solid-state Electronics Saint Petersburg State UniversitySaint Petersburg 199034Russia Department of Physics Omsk State Technical UniversityOmsk 644050Russia

High-speed solar-blind short wavelength ultraviolet radiation detectors based onκ(ε)-Ga_(2)O_(3)layers with Pt contacts were demonstrated and their properties were studied in ***κ(ε)-Ga_(2)O_(3)layers were deposited by the halide vapor phase epitaxy on patterned GaN templates with sapphire *** spectral dependencies of the photoelectric properties of struc-tures were analyzed in the wavelength interval 200-370 *** maximum photo to dark current ratio,responsivity,detectiv-ity and external quantum efficiency of structures were determined as:180.86 ***.,3.57 A/W,1.78×10^(12) Hz^(0.5)∙cm·W^(-1) and 2193.6%,respectively,at a wavelength of 200 nm and an applied voltage of 1 *** enhancement of the photoresponse was caused by the decrease in the Schottky barrier at the Pt/κ(ε)-Ga_(2)O_(3)interface under ultraviolet *** detectors demon-strated could functionalize in self-powered mode due to built-in electric field at the Pt/κ(ε)-Ga_(2)O_(3)*** responsivity and external quantum efficiency of the structures at a wavelength of 254 nm and zero applied voltage were 0.9 mA/W and 0.46%,*** rise and decay times in self-powered mode did not exceed 100 ms.

关键词： κ(ε)-gallium oxide solar-blind shortwave ultraviolet radiation detectors self-powered operation mode

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Test results of railway ballast for bearing capacity calculations

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Research in Cold and Arid Regions 2017年第3期9卷 312-316页

作者： Alexey F.Kolos Anastasia A.Konon emperor alexander i st.petersburg state transport university Construction of Roads for Transportation Complex Department

This paper presents the results of field and laboratory tests of railway *** tests were aimed to study vibrational acceleration of ballast particles and ballast layer stressed state in terms of train traffic with heavy axle *** test results are vibrational acceleration and stress values distribution in ballast layer and experimental relationships of vertical and horizontal vibroaccelerations damping in terms of train operation with axle load up to 300 k *** stabilometer tests were directed to study the change of ballast strength properties due to vibrodynamic impact and shows that for dynamic loading with 10,25,55 Hz frequencies vibrodynamic impact influences strength properties insignificantly and coincides with the accuracy of test *** test results provide references for calculation of ballast and sub-ballast bearing capacity.

关键词： ballast vibrational acceleration vertical stress heavy axle load stabilometer

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influence of polyolefin fibers on the strength and deformability properties of road pavement concrete

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Journal of Traffic and transportation Engineering(English Edition) 2019年第4期6卷 407-417页

作者： Olga Smirnova Alexey Kharitonov Yuriy Belentsov Department of Constructing Mining Enterprises and Underground structures Saint-Petersburg Mining UniversitySaint Petersburg 199106Russia Department of Technology of Building Materials and Metrology Saint-Petersburg State University of Architecture and Civil EngineeringSaint Petersburg 190005Russia Department of Building Materials and Technologies Emperor Alexander I St.Petersburg State Transport UniversitySaint Petersburg 190031Russia

influence of the type and quantity of polyolefin fibers on the strength properties(compression strength, tensile strength in bending, strength in uniaxial tension), the deformation properties(elastic modulus, Poisson’s coefficient) and the abrasion resistance of cement concrete with water-to-cement ratio within 0.31 e0.55 were stated in the *** ways of fibers introduction into fresh concrete were investigated. it was shown that the fibers introduction method and procedure of mixing are the ways to improve the fibers uniform distribution in fresh concrete. The increase of the bending tensile strength and the uniaxial tensile strength of concrete with fibers reinforcement in comparison with the reference concrete was observed with the water-to-cement ratio decrease. The increase of uniaxial tensile strength at age of 28 days for concrete with macrofibers in amount of4.5 kg/m^3 was 23% and 29%;for macrofibers in quantity of 3 kg/m^3 was 19% and 26% with water-cement ratio equal to 0.49 and 0.31, respectively. The maximum reduction of abrasion in the range of 7.5%e10% was observed in concrete with water-to-cement ratio within0.44 e0.55 for all investigated types of fibers. The influence of fibers on the concrete abrasion with lower W/C ratio was negligible. The results can contribute to the rational use of modified polyolefin fibers in road pavement concrete.

关键词： Road pavement concrete Polyolefin fibers strength Elastic modulus Abrasion Water-to-cement ratio

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Year-round cooling and thermal stabilization of water-saturated soils under engineering structures

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Research in Cold and Arid Regions 2017年第3期9卷 258-260页

作者： Vladimir Moiseev Nicolai Vasiliev Tatyana Komarova Olga Komarova Department of Mathematics Emperor Alexander I St.Petersburg State Transport University static Research of Soils Laboratory B.E.Vedeneev VNIIG JSC DiSist Scientific Center

We consider the problem of year-round cooling of water-saturated soil to freezing temperatures in order to convert it into a state of permafrost.A new soil-cooling apparatus is *** apparatus is to be made in modular form and connected to passive-active thermal piles(thermosyphons).The estimated capacity of one apparatus allows simultaneous use of up to 1,000 thermal piles for ground *** apparatus is based on natural sources of energy:solar radiation and wind;and it can be used for soil *** approach can prevent thawing of soft soils under railways and roads,as well as under buildings or structures,in an area of more than tens of *** apparatus has no mechanical moving parts and can operate for a long time in stand-alone mode without staff involvement.

关键词： thermopiles frozen soil preventing of thawing the apparatus for cooling

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Metformin prevents hormonal and metabolic disturbances and 1,2-dimethylhydrazine-induced colon carcinogenesis in non-diabetic rats

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Cancer Biology & Medicine 2017年第1期14卷 100-107页

作者： Viktoria V.Bekusova Vasily M.Patsanovskii alexander D.Nozdrachev Alexandr P.Trashkov Margarita R.Artemenko Vladimir N.Anisimov Department of Physiology St.Petersburg State UniversitySt.Petersburg 197183Russia i.P.Pavlov institute of Physiology Russian Academy of Sciences St.Petersburg 199034Russia Deparment of Experimental Pharmacology I.M.Sechenov Institute of Evolutionary Physiology and BiochemistryThe Russian Academy of SciencesSt.Petersburg 194223Russia Department of Carcinogenesis and Oncogerontology N.N.Petrov Research Institute of OncologySt.Petersburg 197758 Russia

Effects of two doses of the anti-diabetic drug, metformin （MF）, on hormonal and metabolic levels of serum of non-diabetic male Wistar rats with 1,2-dimethylhydrazine （DMH）-induced colon tumor adenocarcinomas were studied. Carcinogenesis in the animals was also observed. Rats with DMH-induced colon adenocarcinomas had elevated levels of serum glucose, insulin, insulin- like growth factor-l, total cholesterol, triglycerides, catalase, malonic dialdehyde, glycated hemoglobin, aspartate aminotransferase, and alanine aminotransferase and decreased hemoglobin. Treatment with two doses of MF normalized maiority of these changes in DMH-treated rats, whereas the drug was ineffective in rats without DMH treatment. The only exception was the decreased triglyceride levels in MF-treated rats. A 100 mg/kg dose of MF increased DMH-induced exophytic colon carcinomas and decreased endophytic tumors compared with untreated rats. Moreover, both MF doses increased DMH-induced and highly differentiated tumors and decreased the invasiveness of colon carcinomas compared with rats provided with DMH and water. Therefore, effects of MF on metabolic homeostasis are critical for preventing colon cancer.

关键词： Colon cancer prevention 1,2-dimethylhydrazine mefformin rat

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increased paracellular permeability of tumor-adjacent areas in 1,2-dimethylhydrazine-induced colon carcinogenesis in rats

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Cancer Biology & Medicine 2018年第3期15卷 251-259页

作者： Viktoria V.Bekusova Evgeny L.Falchuk Larisa S.Okorokova Natalia M.Kruglova alexander D.Nozdrachev alexander G.Markov Department of Physiology St.Petersburg State University i.P.Pavlov institute of Physiology Russian Academy of Sciences

Objective: The morphology and functions of the proximal and distal large intestine are not the same. The incidence of colorectal cancer in these regions is also different, as tumors more often appear in the descending colon than in the ascending *** bowel disease and colorectal cancer can increase transepithelial permeability, which is a sign of reduced intestinal barrier function. However, there is not enough evidence to establish a connection between the difference in colorectal cancer incidence in the proximal and distal colon and intestinal permeability or the effects of carcinogenesis on the barrier properties in various areas of the colon. The aim of the study was to assess the permeability of different segments of the large intestine according to a developed mapping methodology in healthy rats and rats with 1,2-dimethylhydrazine(DMH)-induced colon ***: The short circuit current, the transepithelial electrical resistance and the paracellular permeability to fluorescein of large intestine wall of male Wistar rats were examined in the Ussing chambers. The optical density of the solution from the serosa side to assess the concentration of the diffused fluorescein from mucosa to serosa was analyzed by spectrophotometry. The morphometric and histological studies were performed by optical ***: Rats with DMH-induced colon adenocarcinomas showed elevated transepithelial electrical resistance in the areas of neoplasm development. in contrast, there was no change in the electrophysiological properties of tumor adjacent areas, however,the paracellular permeability of these areas to fluorescein was increased compared to the control rats and was characterized by sharply reduced barrier ***: The barrier properties of the colon vary depending on tumor location. The tumors were less permeable than the intact intestinal wall and probably have a negative influence on tumor-adjacent tissues by disrupting their bar

关键词： Rat 1,2-dimethylhydrazine colorectal cancer Ussing chamber short circuit current transepithelial electrical resistance intestinal permeability

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influence of relative compaction and degree of saturation on the deformation characteristics of bentonite under freeze-thaw cycles

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Research in Cold and Arid Regions 2023年第4期15卷 161-170页

作者： Hao Wang Xu Li WenShao Xin Vladimir Nikolaevich Paramonov XueWen Zhao Department of Civil Engineering University of OttawaOttawaON K1N6N5Canada Key Laboratory of Urban Underground Engineering of Ministry of Education Beijing Jiaotong UniversityBeijing 100044China emperor alexander i st.petersburg state transport university St.Petersburg 190031Russia Qingdao transportation Planing and Design institute Co. Ltd.QingdaoShandong 266043China

Bentonite,consisting of clay minerals of the montmorillonite group,has been widely used as an adsorbent and backfill material in nuclear waste disposal and groundwater *** is challenging to use bentonite as a filling material in cold regions since bentonite is highly sensitive to thermal environmental changes,during which its bulk volume and microstructure change *** this study,a series of one-dimensional and three-dimensional freeze-thaw tests were carried out within a closed system to investigate the influencing factors of the deformation of bentonite under freeze-thaw *** show that the initial soil water content greatly impacts bentonite's deformation during freeze-thaw *** an initial higher degree of saturation(Sr),the expansion caused by the formation of ice lenses has a greater impact than the shrinkage induced by dehydration,ice-cementation,and so ***,bentonite tends to shrink at a lower degree of saturation during *** the critical degree of saturation that determines bentonite's behavior of frost heave or frost shrinkage seems to be roughly *** the number of freeze-thaw cycles rises,initially uncompacted bentonite clay becomes more compacted,and initially compacted bentonite clay remains unchanged.

关键词： Bentonite Relative compaction Degree of saturation Freeze-thaw cycles Deformation

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Probiotics and autoprobiotics for treatment of Helicobacter pylori infection

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World Journal of Clinical Cases 2023年第20期11卷 4740-4751页

作者： Natalia V Baryshnikova Anastasia S ilina Elena i Ermolenko Yury P Uspenskiy alexander N Suvorov Department of Molecular Microbiology Institute of Experimental MedicineSt.Petersburg 197376Russia internal Diseases Department of stomatological Faculty Pavlov First St-Petersburg State Medical UniversitySt.Petersburg 197022Russia Laboratory of Medical and Social Pediatric Problems St-Petersburg State Pediatric Medical UniversitySt.Petersburg 194100Russia Clinical Department Institute of Experimental MedicineSt.Petersburg 197376Russia Department of Faculty Therapy Named After V.A.Valdman St-Petersburg State Pediatric Medical UniversitySt.Petersburg 194100Russia

The article discusses various approaches for probiotic treatment of Helicobacter pylori(***)infection:Probiotics as an adjuvant treatment in the standard eradication therapy;probiotic strains as a monotherapy;and autoprobiotics as a *** refer to indigenous bifidobacteria,lactobacilli,or enterococci isolated from a specific individual,intended to restore his/her microbiota and improve his/her *** potential mechanisms of probiotic action against *** include correction of the gut microbiota,immunological effects(enhancement of humoral and cellular immunity,and reduction of oxidative stress),direct antagonistic effects against ***(such as colonization resistance and bacteriocin synthesis),and stimulation of local immunological protection(strengthening of the mucous protective barrier and reduction of gastric mucosa inflammation).The incorporation of probiotics into comprehensive eradication therapy shows promise in optimizing the treatment of *** *** can enhance the eradication rates of ***,reduce the occurrence and severity of side effects,and improve patient *** or autoprobiotic monotherapy can be considered as an alternative treatment approach in cases of allergic reactions and insufficient effectiveness of *** recommend including probiotics as adjunctive medications in *** ***,further randomized multicenter studies are necessary to investigate the effects of probiotics and autoprobiotics against ***,in order to gain a better understanding of their mechanisms of action.

关键词： Helicobacter pylori Probiotic Autoprobiotic Eradication Microbiota Gut immunity

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Origin of the neuro-sensory system: new and expected insights from sponges

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integrative Zoology 2009年第3期4卷 294-308页

作者： EMMANUELLE RENARD Jean VACELET Eve GAZAVE Pascal LAPéBiE Carole BORCHiELLiNi alexander V.ERESKOVSKY Centre d’océanologie de Marseille CNRS–Aix-Marseille UniversitéMarseilleFrance Department of Embryology Saint-Petersburg State UniversitySt.PetersburgRussia

The capacity of all cells to respond to stimuli implies the conduction of information at least over short *** multicellular organisms,more complex systems of integration and coordination of activities are *** most animals,the processing of information is performed by a nervous *** the most basal taxa,sponges are nerveless so that it is traditionally assumed that the integrated neuro-sensory system originated only once in Eumetazoa,a hypothesis not in agreement with some recent phylogenomic *** aim of this review is to show that recent data on sponges might provide clues for understanding the origin of this complex ***,sponges are able to react to external stimuli,and some of them display spontaneous movement *** coordinated behaviors involve nervous system-like mechanisms,such as action potentials and/or ***,genomic analyses show that sponges possess genes orthologous to those involved in the patterning or function-ing of the neuro-sensory system in ***,some of these genes are expressed in specific cells(flask cells,choanocytes).Together with ultrastructural data,this gives rise to challenging hypotheses concerning cell types that might play neuro-sensory-like roles in sponges.

关键词： animal evolution choanocyte flask cells nervous system Porifera signal transduction.

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intestinal microbiome changes in an infant with right atrial isomerism and recurrent necrotizing enterocolitis:A case report and review of literature

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World Journal of Clinical Cases 2022年第29期10卷 10583-10599页

作者： Aleksandra Kaplina Ekaterina Zaikova Artem ivanov Yulia Volkova Tatiana Alkhova Vladimir Nikiforov alexander Latypov Marina Khavkina Tatiana Fedoseeva Tatiana Pervunina Yulia Skorobogatova Svetlana Volkova Vladimir Ulyantsev Olga Kalinina stanislav Sitkin Natalia Petrova Research Laboratory of Physiology and Diseases of Newborns Almazov National Medical Research CentreSt.Petersburg 197341Russia Research Laboratory of Autoimmune and Autoinflammatory Diseases Almazov National Medical Research CentreSt.Petersburg 197341Russia Vladimir Ulyantsev International Laboratory of Computer TechnologiesITMO UniversitySt.Petersburg 197101Russia Department of Cardiovascular Surgery for Children Almazov National Medical Research CentreSt.Petersburg 197341Russia Department of Neonatal Physiology with an iCU Ward Almazov National Medical Research CentreSt.Petersburg 197341Russia Pediatric Cardiac intensive Care Unit Almazov National Medical Research CentreSt.Petersburg 197341Russia Neonatal and Preterm Special Care Unit(2nd stage Care) Almazov National Medical Research CentreSt.Petersburg 197341Russia institute of Perinatology and Pediatrics Almazov National Medical Research CentreSt.Petersburg 197341Russia Express Laboratory of Perinatal Centre Almazov National Medical Research CentreSt.Petersburg 197341Russia Clinical Diagnostic Laboratory Almazov National Medical Research CentreSt.Petersburg 197341Russia Epigenetics and Metagenomics Group Institute of Perinatology and PediatricsAlmazov National Medical Research CentreSt.Petersburg 197341Russia Department of internal Diseases Gastroenterology and DieteticsNorth-Western State Medical University named after I.I.MechnikovSt.Petersburg 191015Russia

BACKGROUND Necrotizing enterocolitis(NEC)is a multifactorial disease that predominantly affects premature *** dysbiosis plays a critical role in NEC pathogenesis in premature *** main risk factor for NEC in term infants is mesenteric hypoperfusion associated with ductaldependent congenital heart disease(CHD)that eventually leads to intestinal *** incidence of NEC in neonates with critical CHD is 6.8%-13%.However,the role of the intestinal microbiome in NEC pathogenesis in infants with ductal-dependent CHD remains *** SUMMARY A male term neonate with right atrial isomerism underwent modified Blalock-Taussig shunt placement on the 14^(th)day of life and had persistent mesenteric hypoperfusion after *** patient had episodes of NEC stageⅡA on the 1^(st)and 28^(th)days after cardiac *** microbial composition was analyzed before and after cardiac surgery by sequencing region V4 of the 16S rRNA *** surgery,species belonging to genera Veillonella and Clostridia and class Gammaproteobacteria were detected,Bifidobacteriaceae showed a low *** first NEC episode was associated with postoperative hemodynamic instability,intestinal ischemiareperfusion injury during cardiopulmonary bypass,and a high abundance of Clostridium paraputrificum(Clostridium sensu stricto i)(56.1%).Antibacterial therapy after the first NEC episode resulted in increased abundance of Gammaproteobacteria,decreased abundance of Firmicutes,and low alpha *** changes in the microbial composition promoted the growth of Clostridium sensu strictoⅠ(72.0%)before the second NEC *** A high abundance of Clostridium sensu strictoⅠand mesenteric hypoperfusion may have contributed to NEC in the present case.

关键词： Necrotizing enterocolitis Congenital heart disease ivemark syndrome Heterotaxy Right atrial isomerism intestinal microbiome Case report

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