Remote observations of the asteroid (1) Ceres from ground- and space-based telescopes have provided its approximate density and shape, leading to a range of models for the interior of Ceres, from ...homogeneous to fully differentiated. A previously missing parameter that can place a strong constraint on the interior of Ceres is its moment of inertia, which requires the measurement of its gravitational variation together with either precession rate or a validated assumption of hydrostatic equilibrium. However, Earth-based remote observations cannot measure gravity variations and the magnitude of the precession rate is too small to be detected. Here we report gravity and shape measurements of Ceres obtained from the Dawn spacecraft, showing that it is in hydrostatic equilibrium with its inferred normalized mean moment of inertia of 0.37. These data show that Ceres is a partially differentiated body, with a rocky core overlaid by a volatile-rich shell, as predicted in some studies. Furthermore, we show that the gravity signal is strongly suppressed compared to that predicted by the topographic variation. This indicates that Ceres is isostatically compensated, such that topographic highs are supported by displacement of a denser interior. In contrast to the asteroid (4) Vesta, this strong compensation points to the presence of a lower-viscosity layer at depth, probably reflecting a thermal rather than compositional gradient. To further investigate the interior structure, we assume a two-layer model for the interior of Ceres with a core density of 2,460-2,900 kilograms per cubic metre (that is, composed of CI and CM chondrites), which yields an outer-shell thickness of 70-190 kilometres. The density of this outer shell is 1,680-1,950 kilograms per cubic metre, indicating a mixture of volatiles and denser materials such as silicates and salts. Although the gravity and shape data confirm that the interior of Ceres evolved thermally, its partially differentiated interior indicates an evolution more complex than has been envisioned for mid-sized (less than 1,000 kilometres across) ice-rich rocky bodies.
Trematode infection of the second intermediate hosts can lead to changes in their fitness and, as a result, a change in the invasion rate of animal communities. It is especially pronounced during the ...invasion of parasite species that reduce activity due to the manipulation of hosts through the changes of their morphology and physiology. One of these cases is an anomaly P syndrome hotspot found in some populations of water frogs and toads in Europe caused by the trematode Strigea robusta metacercariae. The occurrence of pathogen and their participation in ecosystems are intrigues questions in the anomaly P phenomenon, as well as the role of planorbid snails that serve as the first intermediate hosts for many trematode species. Herein, we focused on trematodes spectra from planorbid snails and amphibians from the anomaly P hosts with the aim to undetected interactions between the pathways of parasites. Emerging cercariae of 6802 planorbid snails of dominant species (Planorbarius corneus, Planorbis planorbis, and Anisus spp.) were detected by both morphological and molecular methods in seven waterbodies in Privolzhskaya Lesostep Nature Reserve (Russia). A total of 95 sequences of 18 species were received, and 48 sequences were unique and did not present in any genetic databases. The 18 species of trematodes from snails and 14 species of trematodes from amphibian hosts (Pelophylax ridibundus; Ranidae; Anura) were detected. Three species (Echinostoma nasincovae, Tylodelphys circibuteonis and Australapatemon burti) was new for the trematode fauna of the Middle Volga River region and Russia as a whole. Eleven species of parasitic flatworms have amphibians in their life cycles and nine species used amphibians as metacercariae hosts: Echinostoma nasincovae, E. miyagawai, Echinoparyphium recurvatum, Tylodelphys circibuteonis, Neodiplostomum spathula, Paralepoderma cloacicola, Macrodera longicollis, Strigea robusta, and Strigea strigis. The occurrence of trematode species from planorbid mollusks and frogs were compared.
•Vesta spherical harmonic gravity field to degree 20 (42-km resolution).•Vesta pole determination error<0.0001 deg.•Detection of combined Vesta pole precession and nutation.•Vesta ephemeris ...improvement to 10-m in Earth-Vesta direction.
The Vesta gravity field and related physical parameters have been precisely measured using 10-months of radiometric Doppler and range data and optical landmark tracking from the Dawn spacecraft. The gravity field, orientation parameters, landmark locations, and Vesta’s orbit are jointly estimated. The resulting spherical harmonic gravity field has a half-wavelength resolution of 42km (degree 20). The gravitational mass uncertainty is nearly 1 part in 106. The inertial spin pole location is determined to better than 0.0001° and the uncertainty in the rotation period has been reduced by nearly a factor of 100. The combined precession and nutation of the pole of Vesta has been detected with angular rates about 70% of expected values, but not well enough to constrain the moment of inertia. The optical landmark position estimates reduce the uncertainty in the center-of-mass and center-of-figure offset to 10m. The Vesta ephemeris uncertainty during the Dawn stay was reduced from 20km to better than 10m in the Earth–Vesta direction.
The adsorption and photodynamic efficiency of 5,10,15,20-tetrakis(p-sulfonatophenyl)porphyrin (H2TPPS4) on bilayer lipid membranes (BLM) have been studied. The adsorption of H2TPPS4 on BLM leads to ...rising of the potential drop on the membrane/water interface which has been detected either by the intramembrane field compensation (IFC) method, or as ζ-potential of liposomes measured by the dynamic light scattering method. The dependence of this potential on the concentration of H2TPPS4 and KCl in the solution can be described in the frame of Gouy-Chapman model of diffuse double layer assuming that the molecules of H2TPPS4 adsorb on the surface of BLM as an anions with four charged groups. The potential disappeared when the pH of solution decreased from 6 to 3 allowing the conclusion that the protonated forms of H2TPPS4 can not adsorb on the BLM probably due to change of conformation or aggregation of the molecules. The photodynamic efficiency of H2TPPS4 was evaluated by measuring the rate of damage of the targets - molecules of styryl dye (di-4-ANEPPS) by singlet oxygen generated under illumination on the surface of BLM. This rate was proportional to the surface density of H2TPPS4 molecules on the membrane which was determined from the change of surface charge of the membrane due to adsorption of the H2TPPS4. These results indicate that the di-4-ANEPPS molecules are damaged by singlet oxygen generated by monomers of H2TPPS4 molecules adsorbed on the membrane. The rate of oxidation of di-4-ANEPPS molecules adsorbed on the same (cis) side of the membrane together with the H2TPPS4 molecules was either the same or higher than that when di-4-ANEPPS molecules were adsorbed on opposite (trans) side. It indicates that the quenching of singlet oxygen by the di-4-ANEPPS molecules at cis side of the membrane was negligible, in contrast to our earlier study when singlet oxygen was generated by aluminum(III) phthalocyanines with one or two peripheral sulfo groups. The difference between these phthalocyanines and H2TPPS4 was explained by their different adsorption depth in the membrane.
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•The H2TPPS4 molecules adsorb on phospholipid membrane as anions with 4 charged groups.•There is no adsorption at pH < 3 when H2TPPS4 bind 2 protons or without phospholipids.•Photodynamic efficiency of H2TPPS4 was measured as rate R of damage of di-4-ANEPPS.•R is proportional to surface density of the H2TPPS4 molecules on the membrane.•R does not depend on what side of membrane the di-4-ANEPPS molecules were adsorbed.
Introduction
Schizophrenia pathogenesis is known to be associated with chronic low-grade inflammation. Inflammation can be caused by extracellular histones that are released from cells due to ...apoptosis dysfunction. It can also be accompanied by the formation of natural catalytic immunoglobulins that bind and hydrolyze histones.
Objectives
To investigate the ability to hydrolyze various histones by polyclonal IgGs from serum of patients with schizophrenia.
Methods
We recruited 50 patients (28 men and 22 women) with a verified diagnosis of paranoid or simple schizophrenia and 25 healthy individuals (13 men and 12 women) in our study. IgG preparations were obtained by affinity chromatography and analyzed by SDS-PAGE and MALDI MS. Catalytic activity of IgGs were revealed by the degree of hydrolysis of five histones using SDS-PAGE. To prove that antibodies exhibit histone-hydrolyzing activity, we used rigorous generally accepted criteria. Statistical analysis was performed in Origin 2019.
Results
IgGs of patients are shown to bind and hydrolyze various histones with high efficiencies. The IgGs histone-hydrolyzing activity level, depending on the type of histone (H1, H2a, H2b, H3, H4), was statistically significantly 6–20 times higher than that of healthy individuals (Fig. 1). However, only 21% of patients with schizophrenia had IgGs with very high activity. The IgGs activity level correlated with PANSS General scale.
Fig.1. Histone-hydrolyzing activity of IgG.
Conclusions
We suggest that histone-hydrolyzing antibodies may play a compensatory role in schizophrenia because removal of extracellular histones minimizes the inflammatory responses. Therefore, such IgGs may be the link between inflammation and humoral immunity, and also be a promising biomarker.
Conflict of interest
This work was supported by Russian Foundation for Basic Research under grant 20-015-00156. E.A.E. is the recipient of the fellowship of the President of the Russian Federation (SP-2258.2019.4).
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•Spontaneous interfacial convection affects joint mass transfer of components.•Kinetic regularities of joint extraction of acetic acid and iodine are established.•Unidirectional mass ...transfer of Iodine, in presence of acetic acid, is enhanced 20 fold.•Threshold driving force for spontaneous interfacial convection is identified.•Semi empirical model is developed to consider spontaneous interfacial convection.
This article focuses on the experimental work supported by theoretical model of the multicomponent mass transfer during extraction driven by spontaneous interfacial convection (SIC). The regularities of individual and joint unidirectional and reciprocal mass transfer of components with different surface-active properties in the benzene-water extraction system at a flat phase interface are considered. The article demonstrates that both the diffusion and convective hydrodynamics of the flow affect the intensity of unidirectional and counter-mass transfer of the components under the conditions of SIC. Marangoni instability at the interface causes local convection, which enhances the mass transfer rate considerably. Experimental studies have shown that the joint unidirectional mass transfer of acetic acid and iodine from organic phase to aqueous phase under the conditions of SIC can be characterised by an increase in the iodine mass transfer coefficient in comparison with its individual mass transfer. It has found that with the acetic acid the unidirectional mass transfer of iodine can be increased by more than 20 times compared to its mass transfer without acid. However in case of counter-transfer of acetic acid and iodine, both the acetic acid as well as iodine mass transfer coefficients decrease compared to their individual mass transfer situations. The experimental data are in accord with the theoretical justification. A simplistic semi empirical theoretical model is developed for joint mass transfer, to estimate the coefficient of mass transfer of the components. The satisfactory convergence of the experimental and calculated data are shown.
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•Ni–Mo alloy favors decarboxylation pathway of ethyl caprate conversion.•The hydrodeoxygenation of ethyl caprate is preferred on Ni–Mo–C sites.•β-Mo2C is responsible for hydrogenation ...reaction of ethyl caprate.•Ni sites present in Ni–Mo alloy favor the hydrodeoxygenation of anisole.•β-Mo2C leads to the formation of a high content of benzene.
Mo- and Ni-containing carbide catalysts were prepared by a Pechini-based method using citric acid as a complexing agent. All the catalysts were characterized by temperature-programmed reduction, X-ray diffraction (XRD), X-ray photoelectron spectroscopy, and N2 and CO sorption. The XRD experiments showed that the bimetallic systems contain phases: β-Mo2C and Mo3Ni2C and an alloy NixMo1−x with a high nickel content. The catalysts were tested in the hydrogenation of ethyl caprate and anisole. For the process with ethyl caprate, it was shown that the catalytic activity rises with an increase of the carbide phase content in the bimetallic catalysts. Further addition of nickel increases the amount of the Ni–Mo alloy, which leads to a drop in the catalytic activity and to an increase in the contribution of the decarboxylation pathway. The study of the carbide catalysts in anisole hydrogenation showed that a rise in the Ni/Mo ratio leads to an increase in activity.
Abstract
The stellar, gaseous and young stellar disks in the LITTLE THINGS sample of nearby dwarf irregular galaxies are fitted with functions to search for correlations between the parameters. We ...find that the H
i
radial profiles are generally flatter in the center and fall faster in the outer regions than the
V
-band profiles, while young stars are more centrally concentrated, especially if the H
i
is more centrally flat. This pattern suggests that the H
i
is turning into molecules in the center, and the molecular clouds are forming stars and FUV. A model that assumes the molecular surface density is proportional to the total gas surface density to a power of 1.5 or 2, in analogy with the Kennicutt–Schmidt relation, reproduces the relationship between the ratio of the visible to the H
i
scale length and the H
i
Sérsic index. The molecular fraction is estimated as a function of radius for each galaxy by converting the FUV to a molecular surface density using conventional calibrations. The average molecular fraction inside 3
R
D
is 23% ± 17%. However, the break in the stellar surface brightness profile has no unified tracer related to star formation.
Effects of copper ions and copper oxide nanoparticles on lipid peroxidation rate, activities of anti-oxidant enzymes (superoxide dismutase, catalase, and peroxidase), and photosynthesis have been ...studied in experiments with Elodea densa Planch. The results show that nanoparticles are more actively accumulated by plants. Both copper ions and nanoparticles activate lipid peroxidation (to 120 and 180% of the control level, respectively). Catalase and superoxide dismutase activities in plants treated with nanoparticles increase by a factor of 1.5–2.0. Copper ions suppress photosynthesis at a concentration of 0.5 mg/l, whereas nanoparticles produce such an effect only at 1.0 mg/l. The observed effects of different forms of copper on E. densa are discussed in a comparative aspect.
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