ABSTRACT
We present results of polarimetric, photometric, and spectral observations of the near-Earth asteroid (3200) Phaethon carried out at the 6-m BTA telescope of the Special Astrophysical ...Observatory and the 2.6-m and 1.25-m telescopes of the Crimean Astrophysical Observatory over a wide range of phase angles during its close approach to the Earth at the end of 2017 (α = 19°–135°) and in 2020 at α = 52.2°. Using our and other available in literature data, we found that the maximum degree of linear polarization of Phaethon in the V band is Pmax = (45 ± 1) per cent at the phase angle αmax = 124.0° ± 0.4°, whereas the inversion angle αinv = 21.4° ± 1.2° and polarimetric slope is h = (0.326 ± 0.027) per cent per degree. Using the dependence ‘polarimetric slope – albedo,’ we have found the geometric albedo of asteroid Phaethon to be pv = 0.060 ± 0.005. This value falls into the lower range of albedo values for asteroids determined by different methods. The mean colour indices U–B = 0.207 m ± 0.053 m and B–V = 0.639 m ± 0.054 m of the asteroid are derived at heliocentric and geocentric distances 1.077 au and 0.102 au, respectively, and phase angle α = 23.78°. The absolute magnitude of Phaethon is V(1,1,0) = 14.505 m ± 0.059 m. The effective diameter of Phaethon is estimated from obtained absolute magnitude and geometrical albedo, it is equal to 6.8 ± 0.3 km. The best fit to the observed polarimetric data was obtained with the Sh-matrix model of conjugated random Gaussian particles composed of Mg-rich silicate (90 per cent) and amorphous carbon (10 per cent).
We are interested in the modelling of multi-dimensional turbulent hydraulic jumps in convergent radial flow. To describe the formation of intensive eddies (rollers) at the front of the hydraulic ...jump, a new model of shear shallow water flows is used. The governing equations form a non-conservative hyperbolic system with dissipative source terms. The structure of equations is reminiscent of generic Reynolds-averaged Euler equations for barotropic compressible turbulent flows. Two types of dissipative term are studied. The first one corresponds to a Chézy-like dissipation rate, and the second one to a standard energy dissipation rate commonly used in compressible turbulence. Both of them guarantee the positive definiteness of the Reynolds stress tensor. The equations are rewritten in polar coordinates and numerically solved by using an original splitting procedure. Numerical results for both types of dissipation are presented and qualitatively compared with the experimental works. The results show both experimentally observed phenomena (cusp formation at the front of the hydraulic jump) as well as new flow patterns (the shape of the hydraulic jump becomes a rotating square).
Urokinase-type plasminogen activator uPA and its receptor (uPAR) are the central players in extracellular matrix proteolysis, which facilitates cancer invasion and metastasis. EGFR is one of the ...important components of uPAR interactome. uPAR/EGFR interaction controls signaling pathways that regulate cell survival, proliferation and migration. We have previously established that uPA binding to uPAR stimulates neurite elongation in neuroblastoma cells, while blocking uPA/uPAR interaction induces neurite branching and new neurite formation. Here we demonstrate that blocking the uPA binding to uPAR with anti-uPAR antibody decreases the level of pEGFR and its downstream pERK1/2, but does increase phosphorylation of Akt, p38 and c-Src Since long-term uPAR blocking results in a severe DNA damage, accompanied by PARP-1 proteolysis and Neuro2a cell death, we surmise that Akt, p38 and c-Src activation transmits a pro-apoptotic signal, rather than a survival.
Serum deprivation resulting in enhanced neuritogenesis is accompanied by an upregulated uPAR mRNA expression, while EGFR mRNA remains unchanged. EGFR activation by EGF stimulates neurite growth only in uPAR-overexpressing cells but not in control or uPAR-deficient cells. In addition, AG1478-mediated inhibition of EGFR activity impedes neurite growth in control and uPAR-deficient cells, but not in uPAR-overexpressing cells. Altogether these data implicate uPAR as an important regulator of EGFR and ERK1/2 signaling, representing a novel mechanism which implicates urokinase system in neuroblastoma cell survival and differentiation.
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•uPAR is an important regulator of neuroblastoma cell survival and differentiation.•uPAR is upstream of the EGFR/ERK1/2 signaling pathway.•EGFR/ERK1/2 controls cell survival in the absence of uPAR.•EGFR/ERK1/2 promotes neurite growth in uPAR-expressing cells.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
► We optimize electrochromic cell, working and counter electrodes, polymeric electrolyte. ► We study optical behavior of WO3-MoO3 and MoO3-Cr2O3, and their vibrational properties. ► Electrochromic ...properties WO3-MoO3 are excellent, MoO3-Cr2O3 film is optically passive. ► An electrochromic device was constructed with a polymeric electrolyte.
A smart window is a device controlling the energy of solar flux entering building or car and makes the interiors comfortable and the solar energy utilization more effective. We have developed an optimized APCVD technology for thin film deposition on conductive glass. The films are capable to change their transmittance if a small voltage is applied across the film.
The paper deals with the optimization of basic elements of electrochromic device: a working electrode of WO3–MoO3 film, a counter electrode of MoO3–CrO3 film, and polymeric electrolyte between them. The extensive research done on these materials led to conclusion, that WO3–MoO3 combines the excellent electrochromic performance of WO3 and the high-growth-rate of MoO3, when fabricated by the carbonyl APCVD process. A color efficiency in the order of 150–200cm2/C and an optical modulation 40–50% (transmittance difference in bleached and color state) were achieved. APCVD Mo/Cr oxide films were developed to serve as counter electrode. They are optically passive. Results from the voltammetry measurements of the electrochromic performance are related to film structure and optical properties analyzed by Raman spectroscopy, FTIR and spectrophotometry techniques. Emphasis was given on polymeric electrolyte, its composition, technology for preparation, and influence on the EC properties.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
OBJECTIVE: To determine the costs and catastrophic costs incurred by drug-susceptible (DS) pulmonary TB patients in The Gambia.METHODS: This observational study collected cost and socio-economic data ...using a micro-costing approach from the household perspective from
244 adult DS-TB patients with pulmonary TB receiving treatment through the national treatment programme in The Gambia. We used data collected between 2017 and 2020 using an adapted version of the WHO generic patient cost survey instrument to estimate costs and the proportion of patients experiencing
catastrophic costs (≥20% of household income).RESULTS: The mean total cost of the TB episode was $104.11 (2018 USD). Direct costs were highest before treatment ($22.93). Indirect costs accounted for over 50% of the entire episode costs. Using different income estimation
approaches and catastrophic cost thresholds, 0.4-75% of participants encountered catastrophic costs, showing the variability of results given the different assumptions we utilised.CONCLUSIONS: We show that despite the benefits of free TB care and treatment, DS-TB patients
still incur substantial direct and indirect costs, and cases of impoverishing expenditure varied vastly depending on the income estimation approaches used.
Treatment options for adenoid cystic carcinoma (ACC) of the salivary gland, a slowly growing tumor with propensity for neuroinvasion and late recurrence, are limited to surgery and radiotherapy. ...Based on expression analysis performed on clinical specimens of salivary cancers, we identified in ACC expression of the neurotrophin-3 receptor TrkC/NTRK3, neural crest marker SOX10, and other neurologic genes. Here, we characterize TrkC as a novel ACC marker, which was highly expressed in 17 out of 18 ACC primary-tumor specimens, but not in mucoepidermoid salivary carcinomas or head and neck squamous cell carcinoma. Expression of the TrkC ligand NT-3 and Tyr-phosphorylation of TrkC detected in our study suggested the existence of an autocrine signaling loop in ACC with potential therapeutic significance. NT-3 stimulation of U2OS cells with ectopic TrkC expression triggered TrkC phosphorylation and resulted in Ras, Erk 1/2 and Akt activation, as well as VEGFR1 phosphorylation. Without NT-3, TrkC remained unphosphorylated, stimulated accumulation of phospho-p53 and had opposite effects on p-Akt and p-Erk 1/2. NT-3 promoted motility, migration, invasion, soft-agar colony growth and cytoskeleton restructuring in TrkC-expressing U2OS cells. Immunohistochemical analysis demonstrated that TrkC-positive ACC specimens also show high expression of Bcl2, a Trk target regulated via Erk 1/2, in agreement with activation of the TrkC pathway in real tumors. In normal salivary gland tissue, both TrkC and Bcl2 were expressed in myoepithelial cells, suggesting a principal role for this cell lineage in the ACC origin and progression. Sub-micromolar concentrations of a novel potent Trk inhibitor AZD7451 completely blocked TrkC activation and associated tumorigenic behaviors. Pre-clinical studies on ACC tumors engrafted in mice showed efficacy and low toxicity of AZD7451, validating our in vitro data and stimulating more research into its clinical application. In summary, we describe in ACC a previously unrecognized pro-survival neurotrophin signaling pathway and link it with cancer progression.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
•Wave coarsening for roll waves down an inclined plane is demonstrated.•Morphological instability of long wave trains on shear ows is observed.•Stability of a single 1-D wave under multi-D ...perturbations is established.
The formation of a periodic roll-wave train in a long channel is studied for two sets of experimental parameters corresponding to Brock’s experiments 3, 4 who measured permanent wave profiles by introducing periodic perturbations at the channel inlet. In both cases, a formed free surface profile is found in good agreement with the experimental results. Qualitative properties of solutions to the model are studied in the case where the perturbation frequency is lower than the experimental one, so longer waves are generated at the channel inlet. It is observed that the corresponding roll-wave train is strongly modulated. In the case where the waves of two different lengths are generated at the channel inlet, the coarsening is observed, i.e. the process where shorter waves disappear progressively by transferring their energy to longer waves forming later a regular roll-wave train. The coarsening phenomenon is always accompanied by a strong modulation. A comparison with the Saint-Venant equations is also performed. The formation of a single wave composing a roll-wave train is also studied in a domain with periodic boundary conditions (called “periodic box”) for the same sets of experimental parameters. The free surface profile is found also in good agreement with the experimental results. This allows us to justify the use of the “periodic box” as a simple mathematical tool for a qualitative study of stability of roll-waves. In particular, we study the stability of a single steady wave by increasing its length. It is shown that the wave becomes morphologically unstable after some critical wave length: it bifurcates into a system of two waves. In the framework of a simplified multi-D model of shear shallow water flows it is also proved that a single steady wave is stable under multi-dimensional perturbations.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Assessment of the network of toxicity pathways by Omics technologies and bioinformatic data processing paves the road toward a new toxicology for the twenty-first century. Especially, the upstream ...network of responses, taking place in toxicant-treated cells before a point of no return is reached, is still little explored. We studied the effects of the model neurotoxicant 1-methyl-4-phenylpyridinium (MPP(+)) by a combined metabolomics (mass spectrometry) and transcriptomics (microarrays and deep sequencing) approach to provide unbiased data on earliest cellular adaptations to stress. Neural precursor cells (LUHMES) were differentiated to homogeneous cultures of fully postmitotic human dopaminergic neurons, and then exposed to the mitochondrial respiratory chain inhibitor MPP(+) (5 μM). At 18-24 h after treatment, intracellular ATP and mitochondrial integrity were still close to control levels, but pronounced transcriptome and metabolome changes were seen. Data on altered glucose flux, depletion of phosphocreatine and oxidative stress (e.g., methionine sulfoxide formation) confirmed the validity of the approach. New findings were related to nuclear paraspeckle depletion, as well as an early activation of branches of the transsulfuration pathway to increase glutathione. Bioinformatic analysis of our data identified the transcription factor ATF-4 as an upstream regulator of early responses. Findings on this signaling pathway and on adaptive increases of glutathione production were confirmed biochemically. Metabolic and transcriptional profiling contributed complementary information on multiple primary and secondary changes that contribute to the cellular response to MPP(+). Thus, combined 'Omics' analysis is a new unbiased approach to unravel earliest metabolic changes, whose balance decides on the final cell fate.
The influence of a permanent magnetic field on macro- and nanoscopic properties of triglycine sulfate (TGS) crystals with impurity chromium (TGS-Cr) has been investigated. This work continues ...the previous studies of magnetically induced effects in ferroelectrics. A specific feature of TGS crystals is the presence of a nanoscale relief on a polar (010) cleavage; this nanorelief is a qualitative characteristic of the crystal defect structure. It is shown that the exposure of a crystal in a magnetic field of 2 T leads to a change in its dielectric properties, accompanied by a long-term transformation of the nanorelief. The results obtained are indicative of a magnetically induced change in the defect crystal structure. A qualitative difference is found between the magnetically induced effects in TGS-Cr crystals and undoped TGS crystals. The relationship between the magnetically induced effects and structural defects is discussed.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Behavioral experiments were run to assess the ability of rhesus monkeys to retain visual objects differing in shape, color, or a combination of these features in working memory. Six male rhesus ...monkeys performed a delayed matching-to-sample task in which three geometric shapes from a set of stimuli served as samples. In the first series of experiments, these were different colored figures of different shapes; samples in the second series were circles of different colors and samples in the third series were monochrome images of a number of figures from the stimulus set. Use of both cues to retain objects in memory resulted in the best performance by the monkeys; animals generally performed better on the color-matching task than the shape-matching task. This result is inconsistent with data reported from a number of other studies, where similar experiments – but with only one sample for memorization – yielded the opposite trend. The reason for this difference may be a shift in the focus of attention from local features (figure outlines) to global features (color) for memorization of information in the conditions of greater load on working memory used in our study.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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