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1.
Stomatologiia (Mosk) ; 103(2): 91-95, 2024.
Artigo em Russo | MEDLINE | ID: mdl-38741542

RESUMO

Based on archival data, the authors describe the Moscow School of Dentistry with dental courses for doctors, dentists, and dentists of the Moscow University, Privat-docent Dr. Gilyari Ivanovich Vilga, examine the background to its formation, provide unique archival data on the location of the school, as well as its internal organization and equipment. The authors review in detail the program of courses, as well as their duration, cost, and form of student accountability. During its existence (1909-1918), more than two thousand dentists were educated at G.I. Vilg's school, among them Alexander Ivanovich Evdokimov, a future corresponding member of the USSR Academy of Medical Sciences, director of the State Institute of Dentistry (GIZ) and the State Institute of Dentistry and Odontology (GIZO). The authors of the article also focus on analyzing the differences in the approaches to the organization of several dental schools, viz: The First Moscow I.M. Kovarsky School of Dentistry and the Second G.I. Vilga School of Dentistry. In his efforts, I.M. Kovarskij's aspirations to establish the best dental school in Russia were crowned with success: a specially constructed and equipped building meeting the state-of-the-art requirements (the building even boasted an X-ray machine), and the best professors and instructors of the University of Moscow of that time were hired. In contrast, G.I. Vilga rented premises for his school, the equipment was in short supply, and he himself was the only eminent professor. Nevertheless, his fierce desire to unite the entire dental community and organize the best dental care for the entire population of Russia allowed his brainchild to enter the top five schools of the time.


Assuntos
Educação em Odontologia , Faculdades de Odontologia , História do Século XX , Moscou , Faculdades de Odontologia/história , Educação em Odontologia/história , Humanos , História da Odontologia , Universidades/história
2.
Eur Phys J C Part Fields ; 84(1): 18, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38205101

RESUMO

High-precision searches for an electric dipole moment of the neutron (nEDM) require stable and uniform magnetic field environments. We present the recent achievements of degaussing and equilibrating the magnetically shielded room (MSR) for the n2EDM experiment at the Paul Scherrer Institute. We present the final degaussing configuration that will be used for n2EDM after numerous studies. The optimized procedure results in a residual magnetic field that has been reduced by a factor of two. The ultra-low field is achieved with the full magnetic-field-coil system, and a large vacuum vessel installed, both in the MSR. In the inner volume of ∼1.4m3, the field is now more uniform and below 300 pT. In addition, the procedure is faster and dissipates less heat into the magnetic environment, which in turn, reduces its thermal relaxation time from 12h down to 1.5h.

3.
Eur Phys J C Part Fields ; 83(11): 1061, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38021215

RESUMO

We present a novel Active Magnetic Shield (AMS), designed and implemented for the n2EDM experiment at the Paul Scherrer Institute. The experiment will perform a high-sensitivity search for the electric dipole moment of the neutron. Magnetic-field stability and control is of key importance for n2EDM. A large, cubic, 5 m side length, magnetically shielded room (MSR) provides a passive, quasi-static shielding-factor of about 105 for its inner sensitive volume. The AMS consists of a system of eight complex, feedback-controlled compensation coils constructed on an irregular grid spanned on a volume of less than 1000 m3 around the MSR. The AMS is designed to provide a stable and uniform magnetic-field environment around the MSR, while being reasonably compact. The system can compensate static and variable magnetic fields up to ±50µT (homogeneous components) and ±5µT/m (first-order gradients), suppressing them to a few µT in the sub-Hertz frequency range. The presented design concept and implementation of the AMS fulfills the requirements of the n2EDM experiment and can be useful for other applications, where magnetically silent environments are important and spatial constraints inhibit simpler geometrical solutions.

5.
Rev Sci Instrum ; 93(9): 095105, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36182526

RESUMO

We present the magnetically shielded room (MSR) for the n2EDM experiment at the Paul Scherrer Institute, which features an interior cubic volume with each side of length 2.92 m, thus providing an accessible space of 25 m3. The MSR has 87 openings of diameter up to 220 mm for operating the experimental apparatus inside and an intermediate space between the layers for housing sensitive signal processing electronics. The characterization measurements show a remanent magnetic field in the central 1 m3 below 100 pT and a field below 600 pT in the entire inner volume, up to 4 cm to the walls. The quasi-static shielding factor at 0.01 Hz measured with a sinusoidal 2 µT peak-to-peak signal is about 100 000 in all three spatial directions and increases rapidly with frequency to reach 108 above 1 Hz.

6.
Prog Biophys Mol Biol ; 175: 3-13, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35987420

RESUMO

A review of the physicochemical models of the movement of protocells and bacteria was performed. The mechanisms of gliding and movement based on flagella are considered. Based on the models, the average speed of movement of protocells and bacteria was calculated. A physicochemical model of bacterial gliding was constructed. The efficiency of the process of converting the energy of ATP into the energy of motion is estimated. A review of models of movement with the help of flagella was performed. A model has been constructed for converting ATP energy into proton and sodium motive forces, which, in turn, are converted into energy of rotor rotation. The problem of the accuracy of operation of nanomachines, on the basis of which the directed movement of bacteria occurs, is discussed. The considered models can be applied to create nanomotors for medical purposes.


Assuntos
Células Artificiais , Flagelos , Bactérias , Movimento , Trifosfato de Adenosina
7.
Dokl Biochem Biophys ; 503(1): 80-84, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35538283

RESUMO

A stimulator of light emission of the fungus was found in an aqueous extract from mycelium of the luminous basidiomycete Neonothopanus nambi after its treatment with ß-glucosidase. The addition of the extract to the luminous mycelium increases the level of light emission from several times to 1.5 orders of magnitude or more. The luminescence stimulator is a low-molecular-weight thermostable compound: it is detected in the permeate after filtering the extract through a 10-kDa cutoff membrane and it retains the stimulating effect after heat treatment at 100°C for 5 min. In the absorption spectrum of the aqueous sample of the stimulator, two main peaks are observed in the shortwave region (205 and 260 nm) and a shoulder in the range of 350-370 nm can be seen. The luminescence stimulator exhibits blue fluorescence with an emission maximum at 440 nm when excited at 360 nm. It was established that the luminescence-stimulating component is not a substrate (or its precursor) of the luminescent system of the N. nambi fungus.


Assuntos
Agaricales , Basidiomycota , Luminescência , Micélio
8.
Georgian Med News ; (320): 77-85, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34897049

RESUMO

The purposes of the research were to study the prevalence of C-344T polymorphism and the distribution of aldosterone synthase gene (CYP11B2) genotypes, to analyze the association of aldosterone concentration with aldosterone synthase gene genotypes, to study the features of left ventricular hypertrophy (LVH) by echocardioscopy and identify their association with different genotypes of the aldosterone synthase gene in young patients with arterial hypertension (AH), depending on the presence or absence of concomitant obesity (or overweight). 123 young patients with essential AH (18-44 years old) were examined, the average age was (32,83±0,58) years old, the male/female ratio was 72/51 respectively. All patients were divided into 3 groups: group 1 (n=41) with normal body weight; group 2 (n=40) with overweight; group 3 (n=42) -with obesity. It was revealed that the "pathological" genotypes (CC+CT) of the aldosterone synthase gene C-344T polymorphism were significantly more frequent in patients as with normal body weight and with concomitant obesity or overweight. In concomitant overweight and obesity the average blood aldosterone concentration was significantly higher, that confirms the presence of additional activation of aldosterone synthesis in such comorbid combination and requires further study of the exact mechanism of this type of hyperaldosteronism. Concomitant overweight and obesity significantly influenced on the echocardiographic parameters characterizing LVH processes in young patients with AH with the significant increased proportion of eccentric LVH. "Pathological" genotypes (CT+TT) of the C-344T polymorphism of the aldosterone synthase gene are associated with a higher blood aldosterone concentration and more expressed LVH processes in young patients with AH.


Assuntos
Citocromo P-450 CYP11B2 , Hipertensão , Adolescente , Adulto , Citocromo P-450 CYP11B2/genética , Feminino , Humanos , Hipertensão/complicações , Hipertensão/genética , Recém-Nascido , Masculino , Obesidade/complicações , Obesidade/genética , Fatores de Risco , Remodelação Ventricular , Adulto Jovem
9.
Eur Phys J C Part Fields ; 81(6): 512, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34720721

RESUMO

We present the design of a next-generation experiment, n2EDM, currently under construction at the ultracold neutron source at the Paul Scherrer Institute (PSI) with the aim of carrying out a high-precision search for an electric dipole moment of the neutron. The project builds on experience gained with the previous apparatus operated at PSI until 2017, and is expected to deliver an order of magnitude better sensitivity with provision for further substantial improvements. An overview is of the experimental method and setup is given, the sensitivity requirements for the apparatus are derived, and its technical design is described.

10.
Eur Phys J A Hadron Nucl ; 57(4): 152, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34776778

RESUMO

Psychological bias towards, or away from, prior measurements or theory predictions is an intrinsic threat to any data analysis. While various methods can be used to try to avoid such a bias, e.g. actively avoiding looking at the result, only data blinding is a traceable and trustworthy method that can circumvent the bias and convince a public audience that there is not even an accidental psychological bias. Data blinding is nowadays a standard practice in particle physics, but it is particularly difficult for experiments searching for the neutron electric dipole moment (nEDM), as several cross measurements, in particular of the magnetic field, create a self-consistent network into which it is hard to inject a false signal. We present an algorithm that modifies the data without influencing the experiment. Results of an automated analysis of the data are used to change the recorded spin state of a few neutrons within each measurement cycle. The flexible algorithm may be applied twice (or more) to the data, thus providing the option of sequentially applying various blinding offsets for separate analysis steps with independent teams. The subtle manner in which the data are modified allows one subsequently to adjust the algorithm and to produce a re-blinded data set without revealing the initial blinding offset. The method was designed for the 2015/2016 measurement campaign of the nEDM experiment at the Paul Scherrer Institute. However, it can be re-used with minor modification for the follow-up experiment n2EDM, and may be suitable for comparable projects elsewhere.

11.
Bull Exp Biol Med ; 172(1): 77-80, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34797450

RESUMO

Biodistribution of nanodiamonds in mice after intravenous administration, activities of AST and ALT, and the level of bilirubin in the blood plasma were studied in 2.5 h and 10, 35, and 97 days after injection of nanodiamonds. In 2.5 h after intravenous injection, nanodiamonds mainly accumulate in the lungs and liver. Then, redistribution of nanodiamonds from all organs to the liver was observed. Activities of AST and ALT and the level of bilirubin in the blood increased after 2.5 h and then decreased to the initial values.


Assuntos
Fígado/metabolismo , Pulmão/metabolismo , Nanodiamantes/análise , Plasma/química , Administração Intravenosa , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Bilirrubina/análise , Masculino , Camundongos , Camundongos Endogâmicos ICR , Nanotecnologia , Distribuição Tecidual
12.
Dokl Biochem Biophys ; 499(1): 220-224, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34426915

RESUMO

A reusable system for phenol determination in an aqueous medium was obtained by adsorption of extracellular oxidase from fungus Neonothopanus nambi onto modified nanodiamonds (MND) synthesized by detonation. It was found that the enzyme strongly binds to MND and exhibits catalytic activity in the reaction of co-oxidation of phenol with 4-aminoantipyrine without the addition of hydrogen peroxide. In the presence of the MND-oxidase complex, a significantly (by an order of magnitude) higher yield of the reaction product is recorded as compared to the yield in the presence of a free enzyme; the mechanism of the revealed effect is discussed. Model experiments have demonstrated the multiple use of the MND-oxidase complex for testing phenol in aqueous samples. The immobilized enzyme exhibits functional activity during long-term (2 months) storage of the MND-oxidase complex at 4°C. The data obtained create the prerequisites for using the created system in environmental monitoring of water pollution with phenol.


Assuntos
Basidiomycota/enzimologia , Técnicas Biossensoriais/métodos , Espaço Extracelular/enzimologia , Nanodiamantes/química , Oxirredutases/metabolismo , Fenol/análise , Água/química , Basidiomycota/citologia , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Oxirredutases/química
13.
Phys Rev Lett ; 125(16): 164802, 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33124843

RESUMO

We demonstrate efficient transverse compression of a 12.5 MeV/c muon beam stopped in a helium gas target featuring a vertical density gradient and crossed electric and magnetic fields. The muon stop distribution extending vertically over 14 mm was reduced to a 0.25 mm size (rms) within 3.5 µs. The simulation including cross sections for low-energy µ^{+}-He elastic and charge exchange (µ^{+}↔ muonium) collisions describes the measurements well. By combining the transverse compression stage with a previously demonstrated longitudinal compression stage, we can improve the phase space density of a µ^{+} beam by a factor of 10^{10} with 10^{-3} efficiency.

14.
Dokl Biochem Biophys ; 490(1): 38-42, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32342311

RESUMO

Using the original technique of treating biomass with ß-glucosidase, a pool of extracellular fungal enzymes was obtained for the first time from the mycelium of basidiomycete Neonothopanus nambi. Two protein fractions containing enzymes with oxidase activity were isolated from the extract by gel-filtration chromatography and conventionally called F1 and F2. Enzyme F1 has a native molecular weight of 80-85 kDa and does not contain chromophore components; however, it catalyzes the oxidation of veratryl alcohol with Km = 0.52 mM. Probably, this enzyme is an alcohol oxidase. Enzyme F2 with a native molecular weight of approximately 60 kDa is a FAD-containing protein. It catalyzes the cooxidation of phenol with 4-aminoantipyrine without the addition of exogenous hydrogen peroxide, which distinguishes it from the known peroxidases. It was assumed that this enzyme may be a mixed-function oxidase. F2 oxidase has Km value 0.27 mM for phenol. The temperature optimums for oxidases F1 and F2 are 22-35 and 55-70°C, and pH optimums are 6 and 5, respectively.


Assuntos
Agaricales/enzimologia , Proteínas Fúngicas/metabolismo , Micélio/metabolismo , Oxirredutases/metabolismo , Oxirredutases do Álcool , Ampirona/química , Biomassa , Catálise , Cromatografia em Gel , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Cinética , Oxirredução , Oxigênio/química , Fenol/química , Temperatura
15.
Phys Rev Lett ; 124(8): 081803, 2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32167372

RESUMO

We present the result of an experiment to measure the electric dipole moment (EDM) of the neutron at the Paul Scherrer Institute using Ramsey's method of separated oscillating magnetic fields with ultracold neutrons. Our measurement stands in the long history of EDM experiments probing physics violating time-reversal invariance. The salient features of this experiment were the use of a ^{199}Hg comagnetometer and an array of optically pumped cesium vapor magnetometers to cancel and correct for magnetic-field changes. The statistical analysis was performed on blinded datasets by two separate groups, while the estimation of systematic effects profited from an unprecedented knowledge of the magnetic field. The measured value of the neutron EDM is d_{n}=(0.0±1.1_{stat}±0.2_{sys})×10^{-26} e.cm.

16.
Georgian Med News ; (297): 88-94, 2019 Dec.
Artigo em Russo | MEDLINE | ID: mdl-32011302

RESUMO

The purpose of the work is to analyze the evolution of the clinical course, diagnosis, treatment and prevention of acute rheumatic fever (ARF) and chronic rheumatic heart disease (RHD), antibiotic therapy of streptococcal infection, using modern analysis of modern literature and our own observations. Diagnostic criteria for the disease were revised. Improving the capabilities of echocardiography can improve the prognosis of the disease through the early use of treatment and prevention. The level of ORL / RHD correlates with the economic development of countries. Mutation of the etiological factor of rheumatism - ß-HSA, the formation of antibiotic resistance, increased migration, tourist activity in countries with high morbidity due to ß-HSA can lead to new outbreaks of this infection. Prevention ARF/RHD is multistage. Thus, using the experience of healthcare in different countries, new approaches to prevention can improve disease control.


Assuntos
Febre Reumática , Cardiopatia Reumática , Infecções Estreptocócicas , Antibacterianos/uso terapêutico , Humanos , Febre Reumática/diagnóstico , Febre Reumática/prevenção & controle , Febre Reumática/terapia , Cardiopatia Reumática/diagnóstico , Cardiopatia Reumática/prevenção & controle , Cardiopatia Reumática/terapia , Infecções Estreptocócicas/complicações , Infecções Estreptocócicas/tratamento farmacológico
17.
Opt Express ; 26(13): 17350-17359, 2018 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-30119547

RESUMO

We report on an optically pumped magnetometer that uses multiple laser beams to pump and probe spin-polarized Cs atoms. The selected sensor geometry allows for operation in finite magnetic fields as well as close to zero field. In finite fields the magnetometer employs free spin precession signals to determine the field modulus and direction as described in a separate publication. This publication focuses on the magnetometer operation close to zero field, which is based on a ground state Hanle resonance. The four laser beams permit the simultaneous measurement of two orthogonal magnetic field components in a differential detection scheme that greatly suppresses technical laser power noise. Sensitivities better than 54 fT/Hz1/2 could be demonstrated simultaneously for both measurement channels in a well shielded environment. A minimum Allan deviation, limited by residual field fluctuations, of better than 40 fT was observed for integration times of 2s. The magnetometer achieves high sensitivity and stability in offset fields as well as close to zero field and is, thus, a universal tool for low frequency magnetic field measurements.

18.
Dokl Biochem Biophys ; 480(1): 135-138, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-30008093

RESUMO

A bifunctional indicating complex was created by immobilization of extracellular oxidases (glucose oxidase and peroxidases) of luminous fungus Neonothopanus nambi onto modified nanodiamonds (MNDs) synthesized by detonation. It was found that the enzymes firmly adsorb onto MND particles and exhibit their catalytic activity. Model in vitro experiments showed that the created MND-enzymes complex is suitable for repeated use for analyte (glucose and phenol) testing and retains its activity after storage at 4°C in deionized water for 1 month. The data obtained offer the prospects for developing a new class of reusable multifunctional indicating and diagnostic test systems on the basis of MNDs and higher fungal enzymes for medical and ecological analytics.


Assuntos
Basidiomycota/enzimologia , Enzimas Imobilizadas/química , Proteínas Fúngicas/química , Nanodiamantes/química , Oxirredutases/química
19.
Dokl Biochem Biophys ; 480(1): 173-176, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-30008104

RESUMO

In in vitro experiments, the possibility of using a luminescent system extracted from the luminous fungus Armillaria borealis has been shown to detect and determine the concentration of hispidin. A linear dependence of the luminescent response on the content of hispidin in solutions in the concentration range of 5.4 × 10-5-1.4 × 10-2 µM was detected. The stability of the enzyme system and the high sensitivity of the bioluminescent reaction allows carrying out multiple measurements with the analyte detection limit of 1.3 × 10-11 g. The obtained results show the prospects of creating a rapid bioluminescent method for the analysis of medical substances or extracts from various biological objects for the presence of hispidin.


Assuntos
Armillaria/química , Misturas Complexas/química , Medições Luminescentes/métodos , Pironas/análise , Sensibilidade e Especificidade
20.
Dokl Biochem Biophys ; 477(1): 394-397, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29297115

RESUMO

In model experiments in vitro, the applicability of the EPR spectrometry method for the detection of modified nanodiamonds (MNDs) in blood and homogenates of mouse organs has been established. A characteristic signal (g = 2.003, ΔH ≈ 10 G) is observed in the samples of biomaterials containing MNDs, the intensity of which increases linearly with the concentration of nanoparticles in the range of 1.6-200 µg MNDs per 1 mL of the sample. The EPR method in biomaterials reveals the presence of intrinsic paramagnetic centers, signals from which are superimposed on the signal from the MNDs. However, the intensity of these signals is small, which makes it possible to register the MNDs using EPR spectrometry with the necessary accuracy. The data obtained open up the prospects of using the EPR method for studies of the interorgan distribution, accumulation, and elimination of MNDs during their intravenous injection into experimental animals.


Assuntos
Espectroscopia de Ressonância de Spin Eletrônica , Nanodiamantes/análise , Animais , Análise Química do Sangue , Química Encefálica , Rim/química , Fígado/química , Camundongos , Miocárdio/química , Baço/química
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