The influence of temperature fluctuations of the reference section of an optical fiber as part of the instrumental part on the absolute measurement error of a distributed fiber-optical temperature ...sensor was performed. The design of the reference section with active temperature control with high stability as part of the instrumental part of the sensor is proposed and experimentally investigated. The efficiency of using active temperature control to improve the repeatability of measurements and reduce the measurement error has been experimentally demonstrated.
The sensitivity of the Sagnac interferometer for various acoustic influence coordinates was studied. The principles of the formation of a dead zone in an acoustic distributed fiber-optic sensor based ...on the Sagnac interferometer have been obtained and experimentally confirmed. The response of the interferometer was studied for different types of acoustic impact on the circuit: in the form of a rectangular pulse, sinusoidal, and in the form of a periodic triangular function. The nature of the change in the phase difference at the output of the Sagnac interferometer for each of them was studied. With the found value of the typical frequency
= 10.8 kHz and a loop length of 20 km, numerical simulation and experimental study of the amplitude of the phase difference under acoustic impact through each 1 km of the loop in the range from 0 to 10 km were carried out. A dead zone elimination method is proposed for integrating the Sagnac interferometer into a complex monitoring system using a phase-sensitive optical time domain reflectometer.
Abstract
Harmful motor vehicle emissions are often the primary source of urban air pollution worldwide. Incorrectly serviced high-mileage motor vehicles emit significantly more harmful substances ...into the atmosphere than established by accepted standards. This paper presents an algorithm for the process of diagnostics and analysis of the technical condition of the fuel supply system elements for internal combustion engines (ICE) by means of selective sampling of exhaust gases. A gas analyzer system allows for the simultaneous monitoring of the 4 components of exhaust gases: CO, CH, O
2
and CO
2
, assessment of the air-fuel ratio and internal combustion engine crankshaft rotation speed. Studies were carried out on an engine and a series of malfunctions were created artificially, by means of installing faulty elements and additional elements simulating different degrees of wear on the ICE systems. The study resulted in the development of a method and a hardware and software system. These allow for the test regimes to be established, in order to determine the failure of ICE systems which affect the composition of the exhaust gas.
New ambipolar polyimides containing pendant electron-acceptor groups of the thioxanthenone series are shown to have a high thermal stability (up to 400 °C), a good film-forming ability, and a band ...gap 3.15 <
E
g
< 3.42 eV (
T
= 295 K). By spin-coating of polyimide solutions onto
p
++
-Si(100) silicon plates, model resistive memory devices of the metal–dielectric–metal type with an average polymer layer thickness of ~40 nm and aluminum counter electrodes are made and tested. The devices demonstrate non-volatile memory of the WORM type.
Dopamine transmission is known to play an important role in the reinforcement system of the brain. Studies have identified dopamine system genes whose polymorphic variants have been linked with the ...intensity of psychological traits reflecting the tendency to form behaviors characterized by impulsivity and the need for additional stimulation. The aim of the present work was to seek associations between polymorphisms in the catechol-O-methyltransferase (COMT) and D4 dopamine receptor (DRD4) genes and personality traits in the Russian population. Studies of 130 subjects showed that carriers of the Met/Met genotype of the COMT gene had a greater intensity of the novelty-seeking trait than carriers of the Val/Val and Val/Met genotypes, though this association was seen only in women. In addition, the presence of the C allele of the DRD4 gene in carriers of the Met/Met genotype showed high levels of extraversion and hypomania. These results are consistent with current theoretical concepts of the regulation of dopamine transmission in the brain.
Synaptosomal protein SNAP-25 is involved in the process of transmitting nerve spikes in the CNS and in the consolidation of memory traces in the hippocampus. Two independent studies have demonstrated ...associations between SNAP-25 gene polymorphisms and intellectual functions in a group of mentally healthy subjects and patients with schizophrenia. The aim of the present work was to perform a comparative study of the association between the MnlI polymorphism of SNAP-25 and cognitive functions (verbal memory, attention/executive functions) in 66 patients with endogenous psychoses, 75 of their mentally healthy relatives, and 136 healthy control subjects. Statistical analysis showed that the effectiveness of performing cognitive tests was significantly affected by group assignment (
p
= 0.00001) and genotype (
p
= 0.012). The interaction between genotype and group assignment also had an influence (
p
= 0.02). In all groups, carriers of the TT genotype had worse measures than carriers of other genotypes. The similar nature of the influences of the MnlI polymorphism on variations in measures in all groups indicates that this gene is related to overall intellect.
We studied the relationship between
DRD5
gene polymorphism presented by microsatellites with cognitive signs in 152 schizophrenic patients, 81 mentally healthy relatives, and 125 mentally healthy ...control individuals. An association was found between
DRD5
polymorphism with efficiency of visual voluntary attention in patients (
p
=0.02) and their relatives (
p
=0.006). Carriers of two copies of the 148-b.p. allele were characterized by low efficiency of attention.
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