Nanoparticles for magnetic biosensing systems Kurlyandskaya, G.V.; Novoselova, Iu.P.; Schupletsova, V.V. ...
Journal of magnetism and magnetic materials,
06/2017, Letnik:
431
Journal Article
Recenzirano
The further development of magnetic biosensors requires a better understanding of the interaction between living systems and magnetic nanoparticles (MNPs). We describe our experience of fabrication ...of stable ferrofluids (FF) using electrostatic or steric stabilization of iron oxide MNPs obtained by laser target evaporation. Controlled amounts of FF were used for in vitro experiments with human mesenchymal stem cells. Their morphofunctional responses in the Fe concentration range 2–1000 maximum tolerated dose revealed no cytotoxicity.
•Stable ferrofluids (FF) were obtained using electrostatic or steric stabilization of iron oxide MNPs obtained by laser target evaporation.•Controlled amounts of FF were used for in vitro experiments with human mesenchymal stem cells.•Cells morphofunctional response in the Fe concentration range 2–1000 maximum tolerated dose revealed no cytotoxicity.•The results can be used for magnetic biosensoring, as well as for an addressed design of cell delivery systems.
The main goal of the Baikal-GVD deep-sea neutrino telescope is to detect high-energy neutrinos of astrophysical origin by reconstructing muon tracks or showers of particles generated in interactions ...of neutrino with water. Since 2020, Baikal-GVD has been monitoring IceCube telescope alerts about detecting neutrinos with energies of more than 100 TeV. This work presents results from searching for matches between Baikal-GVD events and IceCube neutrino alerts from September 2020 to April 2022.
Baikal-GVD is a 1 km
3
scale neutrino telescope now under construction in Lake Baikal. The sensitive volume of the detector is currently around 0.5 km
3
. Muons form through the exchange of W-bosons ...in the interaction between muon- and partial tau-neutrinos near the telescope. The muons then propagate to great distances in the lake’s water. Reconstructing their trajectory allows us to obtain the most accurate estimate of the direction of neutrinos at telescopes of this type. Angular resolution can be as good as 0.5° for fairly long muon tracks. The current state of affairs in analyzing track events at the Baikal-GVD is discussed.
•A real-time RT-PCR assay for EBOV (Zaire) detection was developed and evaluated.•Assay specificity was studied using a representative sampling of viral, bacterial and human RNA/DNA.•The assay ...sensitivity was 5×102 copies per ml.•52 suspected for EVD patients of Donka Hospital Conakry, Guinea, tested positive and 149 tested negative.
In early February 2014, an outbreak of the Ebola virus disease caused by Zaire ebolavirus (EBOV) occurred in Guinea; cases were also recorded in other West African countries with a combined population of approximately 25 million. A rapid, sensitive and inexpensive method for detecting EBOV is needed to effectively control such outbreak. Here, we report a real-time reverse-transcription PCR assay for Z. ebolavirus detection used by the Specialized Anti-epidemic Team of the Russian Federation during the Ebola virus disease prevention mission in the Republic of Guinea. The analytical sensitivity of the assay is 5×102 viral particles per ml, and high specificity is demonstrated using representative sampling of viral, bacterial and human nucleic acids. This assay can be applied successfully for detecting the West African strains of Z. ebolavirus as well as on strains isolated in the Democratic Republic of the Congo in 2014.
Afferents from the C2 spinal nerve (SN) and trigeminal nerve (TN) innervate neighboring cranial territories, and their convergence on the upper cervical dorsal horn neurons represents neural ...substrate of pain referral in primary headache disorders. Unfortunately, little is known about trigeminocervical input to the major spinal nociceptive projection area lamina I. Here, we used ex vivo brainstem-cervical cord preparation for the visually guided whole-cell recording from the upper cervical lamina I neurons. We show that 50% of them receive convergent monosynaptic input from both nerves, whereas 35% and 11% of neurons receive specific supply from the C2 SN and TN, respectively. Altogether, 10 distinct patterns of synaptic input from the C2 SN and TN to lamina I neurons could be identified. Although stimulation of both nerves evoked excitatory/inhibitory responses, more numerous pure inhibitory inputs arose from the TN. We show that cervical and trigeminal nociceptors converge on to lamina I projection and inhibitory neurons. Thus, trigeminocervical input in lamina I is processed in both nerve-specific and convergent circuitries. Afferent convergence on to inhibitory interneurons serves as a feedforward mechanism balancing excitatory drive to projection neurons. Disruption of this balance may cause pain in primary headache syndromes.
The existence of degenerate stationary bound states with square-integrable radial wavefunctions was proven when second-order equations are used with the effective potential of the Reissner–Nordström ...(RN) field with two event horizons for charged and uncharged fermions. The fermions in such states are localized near event horizons within the ranges from zero to several fractions of Compton wavelength of fermions versus the values of gravitational and electromagnetic coupling constants and the values of angular and orbital momenta
j
,
l
. In case of extreme RN fields, the absence of stationary bound states of fermions with the energies of
E
<
mc
2
is shown for solutions of the second-order equation for any value of gravitational and electromagnetic coupling constants. The existence of a discrete energy spectrum is shown for the naked RN singularity, due to the solution of the second-order equation at definite values of physical parameters. The discrete spectrum exists for both charged and uncharged fermions. The naked RN singularity in quantum mechanics with the second-order equation for half-spin particles poses no threat to cosmic censorship, since it is covered with an infinitely large potential barrier. Electrically neutral systems of atomic type (RN collapsars with the definite number of fermions in degenerate bound states) are proposed to consider as particles of dark matter.
The paper focuses on the void swelling processes in materials subjected to radiation, that occur due to the formation of the void ensemble in the crystal lattice. According to the theoretical ...analysis of the kinetics and the pore size distribution with regard to the defect migration, the numerical calculations are performed for void swelling in nickel.
Alginate gels are extensively tested in biomedical applications for tissue regeneration and engineering. In this regard, the modification of alginate gels and solutions with dispersed magnetic ...particles gives extra options to control the rheo-elastic properties both for the fluidic and gel forms of alginate. Rheological properties of magnetic suspensions based on Na-alginate water solution with embedded magnetic particles were studied with respect to the interfacial adhesion of alginate polymer to the surface of particles. Particles of magnetite (Fe3O4), metallic iron (Fe), metallic nickel (Ni), and metallic nickel with a deposited carbon layer (Ni@C) were taken into consideration. Storage modulus, loss modulus, and the shift angle between the stress and the strain were characterized by the dynamic mechanical analysis in the oscillatory mode. The intensity of molecular interactions between alginate and the surface of the particles was characterized by the enthalpy of adhesion which was determined from calorimetric measurements using a thermodynamic cycle. Strong interaction at the surface of the particles resulted in the dominance of the “fluidic” rheological properties: the prevalence of the loss modulus over the storage modulus and the high value of the shift angle. Meanwhile, poor interaction of alginate polymer with the surface of the embedded particles favored the “elastic” gel-like properties with the dominance of the storage modulus over the loss modulus and low values of the shift angle.
One hundred twenty Siberian lemmings (
Lemmus sibiricus
) were studied from Kotelnyi Island in the eastern sector of the Polar basin. The main habitats, abundance, nutrition, shelters, breeding, and ...sex–age structure were described for the first time in the conditions of the arctic climate and the depleted vegetation of the New Siberian Islands. The morphological parameters confirming the subspecific status of the Siberian lemming on these islands are given. The possibility that the collared lemming (
Dicrostonyx torquatus
) inhabited the archipelago during the Late Pleistocene and in the modern period are discussed. The important roles the Siberian lemming could have played in the vegetation cover, the formation of upper soil horizons, the surface microrelief, the microclimate, and the ecosystem productivity of the island are shown.
Analysis of the Monkeypox Virus Genome Shchelkunov, S.N.; Totmenin, A.V.; Safronov, P.F. ...
Virology (New York, N.Y.),
06/2002, Letnik:
297, Številka:
2
Journal Article
Recenzirano
Odprti dostop
Monkeypox virus (MPV) belongs to the orthopoxvirus genus of the family Poxviridae, is endemic in parts of Africa, and causes a human disease that resembles smallpox. The 196,858-bp MPV genome was ...analyzed with regard to structural features and open reading frames. Each end of the genome contains an identical but oppositely oriented 6379-bp terminal inverted repetition, which similar to that of other orthopoxviruses, includes a putative telomere resolution sequence and short tandem repeats. Computer-assisted analysis was used to identify 190 open reading frames containing ≥60 amino acid residues. Of these, four were present within the inverted terminal repetition. MPV contained the known essential orthopoxvirus genes but only a subset of the putative immunomodulatory and host range genes. Sequence comparisons confirmed the assignment of MPV as a distinct species of orthopoxvirus that is not a direct ancestor or a direct descendent of variola virus, the causative agent of smallpox.
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