The reaction of sodium (ethoxycarbonyl)cyclopentadienide C
5
H
4
(CO
2
Et)Na (
1
) with the salt MeC(NMe
2
)(OMe)MeSO
4
leads to the substituted pentafulvene 1,3-(Me
2
NCMe)-(CO
2
Et)C
5
H
3
. Its ...photochemical reaction with iron-naphthalene complex CpFe(C
10
H
8
)PF
6
gives homoannularly 1,3-disubstituted ferrocene {1,3-(CO
2
Et)(COMe)C
5
H
3
}Fe(C
5
H
5
).
Nanostructured materials for magnetic biosensing Kurlyandskaya, Galina V.; Portnov, Dmitriy S.; Beketov, Igor V. ...
Biochimica et biophysica acta. General subjects,
June 2017, 2017-Jun, 2017-06-00, 20170601, Letnik:
1861, Številka:
6
Journal Article
Recenzirano
Magnetic nanoparticles (MNPs) are at the leading edge of the field of biomedical applications and magnetic biosensing.
MNPs were fabricated by electrophysical methods of the laser target evaporation ...(LTE) and spark discharge with electrodynamic acceleration of plasma jumpers (SD). Synthesis of polyacrylamide hydrogel was done in the presence of Fe2O3 MNPs in different concentrations obtained by LTE. FeNi/Ti3/Cu/Ti/FeNi3/Ti multilayers for giant magnetoimpedance (GMI) based sensitive elements were prepared by rf-sputtering for testing a biosensor prototype.
Iron oxide MNPs, ferrofluids, ferrofluids contacting with biological systems, synthetic ferrogels mimicking natural tissues – are the steps of the discussed in this work development of bionanomaterials. Thorough the structural and magnetic studies of a multilayered sensitive element, MNPs and ferrogels insure the complete characterization of biosensor prototype. The GMI responses were carefully evaluated in initial state and in the presence of ferrogel with known concentration of MNPs. SD MNPs had the smallest 5–8nm size. This nanomaterial was characterized by large internal strains of the order of 25×10−3, which can play an important role for the interaction with different biosystems.
Iron oxide MNPs were fabricated by LTE and SD methods. SD MNPs had the smallest 5–8nm size and large internal strains of the order of 25×10−3. Designed GMI biosensor prototype allowed precise evaluation of the stray field of the MNPs present in the ferrogel by evaluating the systematic changes of the GMI in a 20–400MHz frequency range.
This work summarizes recent developments in the field of nanomaterials potentially applicable in magnetic biosensing.
•Magnetic nanoparticles (MNPs) fabricated by the laser target evaporation (LTE) and spark discharge (SD) techniques.•Electrostatically and sterically stabilized ferrofluids and acrilamid ferrogels were prepared on the LTE MNPs basis.•FeNi/Ti3/Cu/Ti/FeNi3/Ti multilayers for giant magnetoimpedance (GMI) sensitive elements were prepared by rf-sputtering.•GMI biosensor prototype was successfully tested in the regime of detection of MNPs in ferrogel.•Iron oxide MNPs fabricated by spark discharge insure the smallest size of 5 to 8nm.•SD MNPs are characterized by large internal strains of the order of 25×−3.
Abstract
The paper attempts to consider such economic and legal category as land, in terms of its role as an environmental object. The tendencies of development of this category in the sphere of ...state policy and dynamics of domestic legislation are investigated. The separate attention is devoted to lands of an agricultural purpose - the most important of all categories of ground fund as it includes the most valuable productive earths. As an object of legal relations, this category of land is a unique natural resource, which can be depleted by inappropriate and illiterate use and requiring large costs to restore their fertility.
Currently, the Baikal-GVD Deep Underwater Neutrino Telescope is being successfully deployed in Lake Baikal. It comprises 96 strings with 3456 optical modules. We present the status and plans for ...further deployment of the Baikal-GVD telescope and discuss the issues related to the development of the next-generation neutrino telescope in Lake Baikal.
The neutrino telescope Baikal-GVD is designed for search for high energy neutrinos whose sources are not yet reliably identified. It currently includes total of 3456 optical modules arranged on 96 ...strings, providing an effective volume of 0.6 km
for cascades with energy above 1 PeV. We discuss the first results from the partially built experiment, which is currently the largest neutrino telescope in the Northern Hemisphere and still growing up.
Today, the personal data of many people is stored in the databases of a large number of organizations. Some of them use this data for advertising purposes, disturbing customers with constant calls ...and SMS messages. The problem is that one cannot tell for sure by looking at an unfamiliar number whether it is an unwanted call from an organization. One can use specialized software tools to solve this problem. This article is devoted to comparing their functionality.
We have performed experiments on the generation of relativistic electron beams in helium gas jets (electron density ∼1020 cm−3) using a femtosecond Ti : sapphire laser. Electron beams with a total ...charge of 0.2−0.5 nC, a maximum electron energy of up to 60 MeV, and a divergence of up to 300 mrad are recorded. The generated electron beams are converted into bremsstrahlung X-rays using a Ta plate 2 mm thick. The average dose of bremsstrahlung radiation in the air at a distance of 1 m from the source was 5.4 ±1.7 mrad per pulse. The emitting region size measured by the blurriness of the X-ray image is about 650 μm (FWHM).
ABSTRACT
Baikal-GVD has recently published its first measurement of the diffuse astrophysical neutrino flux, performed using high-energy cascade-like events. We further explore the Baikal-GVD cascade ...data set collected in 2018–2022, with the aim to identify possible associations between the Baikal-GVD neutrinos and known astrophysical sources. We leverage the relatively high angular resolution of the Baikal-GVD neutrino telescope (2–3 deg.), made possible by the use of liquid water as the detection medium, enabling the study of astrophysical point sources even with cascade events. We estimate the telescope’s sensitivity in the cascade channel for high-energy astrophysical sources and refine our analysis prescriptions using Monte-Carlo simulations. We primarily focus on cascades with energies exceeding 100 TeV, which we employ to search for correlation with radio-bright blazars. Although the currently limited neutrino sample size provides no statistically significant effects, our analysis suggests a number of possible associations with both extragalactic and Galactic sources. Specifically, we present an analysis of an observed triplet of neutrino candidate events in the Galactic plane, focusing on its potential connection with certain Galactic sources, and discuss the coincidence of cascades with several bright and flaring blazars.
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•Composite hydrogel PAA/TiO2 photocatalytic decomposes of the methyl orange dye.•Photocatalytic activity of the gel is governed by the diffusion in polymer matrix.•Diffusion ...coefficient of a dye depends on gel’s networking density.•Mathematical model of photocatalysis by the composite hydrogels is proposed.•Numerical solution yields exponential decay of dye concentration in supernatant.
Theoretical model has been developed for the diffusion-limited photocatalytic degradation of organic dye in aqueous solution by composite hydrogel filament with embedded photocatalyst nanoparticles. The model included transition of dye molecules from the supernatant solution into the composite hydrogel, diffusion of the dye inside and pseudo first-order reaction of dye photocatalytic degradation. Theoretical model was verified by the experimental studies of the methyl orange dye photocatalytic degradation in aqueous solution by composite polyacrylamide hydrogel different degrees of crosslinking with embedded commercial TiO2 nanoparticles Degussa/Evonik P25. The integral rate of the dye concentration diminishing of the supernatant solution can be nicely fitted by a single exponential decay function with an apparent kinetic constant of dye photocatalytic degradation reaction. The dependence of the apparent kinetic reaction constant, the diffusion coefficient of dye through hydrogel and the value of the “true” kinetic reaction constant has been discussed.
Our knowledge about the detailed wiring of neuronal circuits in the spinal dorsal horn (DH), where initial sensory processing takes place, is still very sparse. While a substantial amount of data is ...available on the somatodendritic morphology of DH neurons, the laminar and segmental distribution patterns and consequential function of individual axons are much less characterized. In the present study, we fully reconstructed the axonal and dendritic processes of 10 projection neurons (PNs) and 15 interneurons (INs) in lamina I of the rat, to reveal quantitative differences in their distribution. We also performed whole‐cell patch‐clamp recordings to test the predicted function of certain axon collaterals. In line with our earlier qualitative description, we found that lamina I INs in the lateral aspect of the superficial DH send axon collaterals toward the medial part and occupy mostly laminae I–III, providing anatomical basis for a lateromedial flow of information within the DH. Local axon collaterals of PNs were more extensively distributed including dorsal commissural axon collaterals that might refer to those reported earlier linking the lateral aspect of the left and right DHs. PN collaterals dominated the dorsolateral funiculus and laminae IV–VI, suggesting propriospinal and ventral connections. Indeed, patch‐clamp recordings confirmed the existence of a dorsoventral excitatory drive upon activation of neurokinin‐1 receptors that, although being expressed in various lamina I neurons, are specifically enriched in PNs. In summary, lamina I PNs and INs have almost identical dendritic input fields, while their segmental axon collateral distribution patterns are distinct. INs, whose somata reside in lamina I, establish local connections, may show asymmetry, and contribute to bridging the medial and lateral halves of the DH. PNs, on the other hand, preferably relay their integrated dendritic input to deeper laminae of the spinal gray matter where it might be linked to other ascending pathways or the premotor network, resulting in a putative direct contribution to the nociceptive withdrawal reflex.
Quantitative analyses of spinal lamina I projection neurons (PNs) and interneurons (INs) revealed almost identical dendritic patterns but local axon collateral distribution patterns that are distinct. INs mostly establish connections within the superficial dorsal horn and may bridge its medial and lateral halves. PNs also relay their input locally, to deeper laminae of the spinal gray matter and may link other ascending systems and participate directly in the nociceptive withdrawal reflex.
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