8 research outputs found
Leiomyosarcoma of inferior vena cava and right atrium with Ascites and Jaundice: A case report
Leiomyosarcoma is one of the soft tissue sarcomas that could originate from different parts of body and are mostly presented as retropritoneal mass. Leiomyosarcomas of vascular origin are particularly rare tumors occurring mainly in inferior vena cava (IVC). Here, we report the case of a 35-year-old male patient who presented with ascites and jaundice. Further evaluation revealed large hepatic and cardiac masses with extension to IVC. Since it was not possible to determine the point of origin of leiomyosarcoma, the patient received chemotherapy under diagnosis of metastatic leiomyosarcoma but unfortunately passed away. © 2016, Tehran University of Medical Sciences (TUMS). All rights reserved
Prenatal exposure to diesel exhaust particles causes anxiety, spatial memory disorders with alters expression of hippocampal pro-inflammatory cytokines and NMDA receptor subunits in adult male mice offspring
Air pollution by Diesel exhaust (DE) consists of gaseous compounds and diesel exhaust particles (DEPs). Previous studies show associations between prenatal exposure to diesel exhaust affects the central nervous system (CNS). However, there was not reported that these effects were caused by gaseous compounds, diesel exhaust particles, or both. A limited number of studies in rodent models have shown that exposure to DEPs can result in CNS. Here, we explored the effects of prenatal exposure to DEPs on anxiety and learning and memory in NMRI mice male offspring. Three groups of pregnant mice were exposed to 350�400 μg DEPs/m 3 for 2, 4 and 6 h daily in a closed system room. We examined anxiety and learning and memory in 8-to-9-week-old male offspring using the Elevated plus maze and Morris water maze (MWM) test. Hippocampi were isolated after the behavioral tests and measured pro-inflammatory cytokines and N-methyl-D-aspartate (NMDA) receptor expression by quantitative RT-PCR analysis. Mice exposed to DEPs in utero showed de�cits in the Elevated plus maze and Morris water maze test. In addition, DEPs exposed mice exhibited decreased hippocampal NR2A and NR3B expression. Taken together, our data suggest that maternal DEP exposure is associated with anxiety, disrupts learning and memory and reduction hippocampal NR2A and NR3B expression in male offspring. © 201
Large-scale magnetic fields from inflation due to a -even Chern-Simons-like term with Kalb-Ramond and scalar fields
We investigate the generation of large-scale magnetic fields due to the
breaking of the conformal invariance in the electromagnetic field through the
-even dimension-six Chern-Simons-like effective interaction with a fermion
current by taking account of the dynamical Kalb-Ramond and scalar fields in
inflationary cosmology. It is explicitly demonstrated that the magnetic fields
on 1Mpc scale with the field strength of G at the present time
can be induced.Comment: 18 pages, 6 figures, version accepted for publication in Eur. Phys.
J.
Development and protection evaluation of two new, advanced ceramic composite thermal spray coatings, Al2O3-40TiO2 and Cr3C2-20NiCr on carbon steel petroleum oil piping
Carbon steel is the most commonly used material in the petroleum industry owing to its high performance and relatively low cost compared with highly alloyed materials. The corrosion resistance of carbon steel in aqueous solutions is dependent on the surface layer created on carbon steel. This layer often consists of siderite (FeCO3) and cementite (Fe3C), but it is neither compact nor dense. To improve the carbon steel surface resistance against corrosion and wear, a compact and dense layer can be deposited onto the surface by thermal spray coating. In this research, Al2O3-40TiO2 and Cr3C2-20NiCr were deposited onto mechanical part surfaces by HVOF spray technique. The present study describes and compares the electrochemical behavior of carbon steel, Cr3C2-20NiCr and Al2O3-40TiO2 in 3.5% NaCl using open-circuit potential measurement (OCP) and electrochemical impedance microscopy (EIS) for 36 days. The tribological and mechanical properties are also investigated using a tribometer (pin-on-disc). The results indicate that these chemical composition coatings facilitated significant anti-corrosion and anti-wear improvement. However, the samples coated with Al2O3-40TiO2 exhibited the lowest corrosion rate. In terms of wear performance, both coated samples displayed similar behavior under different loads. Scanning electron microscopy (SEM) showed the distinctive microstructure of the HVOF-sprayed samples before and after corrosion and wear testing
The tribological and electrochemical behavior of HVOF-sprayed Cr3C2–NiCr ceramic coating on carbon steel
High Velocity Oxygen Fuel (HVOF) is an excellent approach to prepare a good, wear-resistant lamella of Chromium Carbide-Nickel Chrome (Cr3C2-NiCr) on carbon steel for high temperature application. This research investigates the effect of a thin, deposited layer of Cr3C2-NiCr on carbon steel in terms of wear and corrosion properties. The microstructure of the HVOF-sprayed Cr3C2-NiCr coating was characterized at each step by scanning electron microscopy. Wear testing was performed with a pin-on-disk tester. Wear weight loss was examined by applying different loads over a 9048.96 m sliding distance. Experimental results show that the wear resistance of the coated sample reduced the risk of seizure compared to the uncoated sample. An electrochemical test was also performed and the behavior of the substrate in the coated sample was investigated in 3.5 NaCl for 27 days. Electrochemical Impedance Spectroscopy (EIS) showed that the HVOF coating has high corrosion resistance and protects the substrate from NaCl electrolyte penetration. So deposition this layer of ceramic composite is protected oil piping from synergistic attack of seawater during the transport of crude oil to the refinery. (C) 2014 Elsevier Ltd and Techna Group S.r.l. All rights reserved
Plasma thermal spray of ceramic oxide coating on carbon steel with enhanced wear and corrosion resistance for oil and gas applications
In this work, carbon steel surface was coated with Al2O3–40 wt% TiO2 composite using thermal spraying method. The tribological properties of the plasma-sprayed Al2O3–40 wt% TiO2 coating were investigated with a tribometer (pin-on-disc) to evaluate and compare the wear properties of coated and uncoated samples under different loads. Additionally, cumulative weight analysis was done to compare wear loss. The results indicate significant anti-wear improvement with an increase in TiO2 from 13 wt% to 40 wt%. The corrosion on coated and uncoated samples was analyzed using AC and DC methods, namely open circuit potential from potentio-dynamic polarization and electrochemical impedance spectroscopy in 3% NaCl solution for 20 days
Prenatal exposure to diesel exhaust particles causes anxiety, spatial memory disorders with alters expression of hippocampal pro-inflammatory cytokines and NMDA receptor subunits in adult male mice offspring
Air pollution by Diesel exhaust (DE) consists of gaseous compounds and diesel exhaust particles (DEPs). Previous studies show associations between prenatal exposure to diesel exhaust affects the central nervous system (CNS). However, there was not reported that these effects were caused by gaseous compounds, diesel exhaust particles, or both. A limited number of studies in rodent models have shown that exposure to DEPs can result in CNS. Here, we explored the effects of prenatal exposure to DEPs on anxiety and learning and memory in NMRI mice male offspring. Three groups of pregnant mice were exposed to 350�400 μg DEPs/m 3 for 2, 4 and 6 h daily in a closed system room. We examined anxiety and learning and memory in 8-to-9-week-old male offspring using the Elevated plus maze and Morris water maze (MWM) test. Hippocampi were isolated after the behavioral tests and measured pro-inflammatory cytokines and N-methyl-D-aspartate (NMDA) receptor expression by quantitative RT-PCR analysis. Mice exposed to DEPs in utero showed de�cits in the Elevated plus maze and Morris water maze test. In addition, DEPs exposed mice exhibited decreased hippocampal NR2A and NR3B expression. Taken together, our data suggest that maternal DEP exposure is associated with anxiety, disrupts learning and memory and reduction hippocampal NR2A and NR3B expression in male offspring. © 201