Ultraviolet Irradiation Induces the Accumulation of Chondroitin Sulfate, but Not Other Glycosaminoglycans, in Human Skin

Ultraviolet (UV) light alters cutaneous structure and function. Prior work has shown loss of dermal hyaluronan after UV-irradiation of human skin, yet UV exposure increases total glycosaminoglycan (GAG) content in mouse models. To more fully describe UV-induced alterations to cutaneous GAG content, we subjected human volunteers to intermediate-term (5 doses/week for 4 weeks) or single-dose UV exposure. Total dermal uronyl-containing GAGs increased substantially with each of these regimens. We found that UV exposure substantially increased dermal content of chondroitin sulfate (CS), but not hyaluronan, heparan sulfate, or dermatan sulfate. UV induced the accumulation of both the 4-sulfated (C4S) and 6-sulfated (C6S) isoforms of CS, but in distinct distributions. Next, we examined several CS proteoglycan core proteins and found a significant accumulation of dermal and endothelial serglycin, but not of decorin or versican, after UV exposure. To examine regulation in vitro, we found that UVB in combination with IL-1α, a cytokine upregulated by UV radiation, induced serglycin mRNA in cultured dermal fibroblasts, but did not induce the chondroitin sulfate synthases. Overall, our data indicate that intermediate-term and single-dose UVB exposure induces specific GAGs and proteoglycan core proteins in human skin in vivo. These molecules have important biologic functions and contribute to the cutaneous response to UV

Numerical Study of Cylinder Drag Coefficient Reduction Using Passive Flow Control

In this study, the cylinder drag coefficient is reduced by using passive flow control. Installing a flat plate in two heights and different longitudinal distances in upstream flow increases the upstream flow momentum of the cylinder, leading to the higher boundary layer flow resistance against adverse pressure gradient which delays the flow separation. The flow separation delay enhances the pressure on the cylinder downstream. Then, the net pressure on the cylinder in the flow direction and, consequently, the cylinder drag coefficient are decreased. In case that the higher flat plate is utilized, the pressure on the upstream side is reduced more, leading to lower drag coefficient. However, for both heights of the flat plate at specific longitudinal distances from the cylinder due to the cavity flow formation between the cylinder and the flat plat, the vortex shedding is suppressed and the cylinder upstream is changed from the pressure side to suction side, leading to lower net pressure on the cylinder in the flow direction and as a result, less drag coefficient. At the optimal flat plate configuration at and , the minimum cylinder drag coefficient reached 90% reduction in comparison to the single cylinder case in the same flow condition. Results show that the drag coefficient reduction behavior is similar for different sub-critical Reynolds numbers due to the constant flow pattern and no considerable variation of the separation point. The entropy generation for the single cylinder and the case where the flat plate is located in its optimal configuration were investigated. The single cylinder has the highest entropy value, while the entropy of the optimal flat plate configuration with the cylinder reaches the lowest value, the same as the drag coefficient. Then, the drag coefficient is reduced by decreasing entropy generation, indicating the direct relation between drag coefficient and entropy generation

Numerical modeling and geometric optimization of single-phase supersonic ejector

In the present study, the performance of the 2D single-phase supersonic ejector with working fluid of air is simulated in ANSYS CFX. The aim is to investigate the velocity field, pressure distribution, primary nozzle flow regime, and entertainment ratio in different operational conditions. The primary pressure inlet with bar and the secondary inlet as an opening with bar at different outlet pressures are simulated. The turbulence model is used. The sidewalls are considered symmetry boundary conditions and the no-slip condition is applied to the ejector walls. Then, the ejector geometry is optimized using Multi-Objective Genetic Algorithm (MOGA) in order to reach greater efficiency. Optimization is performed considering geometric parameters including primary nozzle exit diameter, nozzle exit position, diameter, and length of the constant area section. Sensitivity analysis results show that the diameter of constant area section has major effect on the entertainment and pressure ratios as two objective functions. The nozzle exit position and external diameter of primary nozzle are the second and third dominant parameters that respectively influence the performance of the ejector, while the effect of constant area section length is negligible. Results indicate that by increasing the pressure ratio, the shock train moves upstream and at the design point, the last oblique shock is located in the exit of the constant area section, letting the remaining pressure recovery be done in the subsonic diffuser which reduces the pressure losses and increases the efficiency. Above the critical pressure ratio, due to the movement of the shock train to upstream weakening the shock strength, the suction pressure increases. Then, the pressure difference is reduced, leading to the lower secondary mass flow suction. The optimized ejector in the double choking condition has a % higher entertainment ratio and its operational range is enhanced by percent in comparison to the original geometry

Economical Approach for Determination of Kojic Acid by Nanostructured Ionic Liquid-Based Carbon Paste Sensor

An economical and sensitive nanostructured sensor based on carbon paste electrode (CPE) for the determination of kojic acid (KA) was developed in the current work. The applied CPE was modified with 1-butyl-3-methylimidazolium tetrafluoroborate (1B3MITFB) as a conductive binder and NiO nanoparticles (NiO/NPs). The proposed modified ionic liquid-based carbon paste electrode showed satisfactory concentration range and lower detection limit of 5.0�600 μM and 0.8 μM at phosphate buffer pH 6.0, respectively. An acceptable reproducibility with a satisfactory analytical characteristic was observed for the proposed sensor in the presence of common interfering compounds. The observed irreversible oxidation behavior of KA at the surface of the NiO/NPs/1B3MITFB/MCPE was controlled under the diffusion step and the diffusion coefficient (D) at the mass transport limited rate found to be 2.3 � 10�4 cm2 s�1. According to the slope of the Tafel plot, the value of 0.625 was calculated for the electron transfer coefficient (α). The acquired data from electrochemical impedance spectroscopy studies confirmed that the presence of NiO NPS and 1B3MITFB as a conductive binder resulted in a significant increase in the electro-oxidation signal of KA. The value of 12.3 kΩ for the Rct of unmodified CPE decreased to the value of 1.7 kΩ for the modified electrode. The obtained results revealed that the proposed modified ionic liquid-based carbon paste electrode could be applied successfully for the analysis of trace amounts of KA in biological samples such as blood serum, urine, and pharmaceutical samples such as liposome carriers containing KA as well as food samples such as vinegar. The synthesized NiO nanoparticles were characterized using XRD and EDAX analyses. The morphology of NiO/NPs is further characterized by SEM. Figure not available: see fulltext. © 2020, Springer Science+Business Media, LLC, part of Springer Nature

Sclerotherapy Induced Takotsubo Syndrome

A 66-year-old female was brought to the emergency department for acute-onset left-sided chest pain. Prior to arrival, she was at an outpatient appointment with a vascular surgeon for elective sclerotherapy treatment of her lower extremity varicose veins. After receiving an IV injection of polidocanol, she developed severe chest pain with left arm and jaw numbness for the first time in her life. Upon arrival to the ED, the patient reported that her symptoms had resolved. Electrocardiogram (ECG) on presentation was significant for T-wave inversions in leads V1-V3. An initial set of cardiac enzymes showed a troponin I level of 0.62 ng/mL, which subsequently increased to 2.26 ng/mL. Her echocardiogram was significant for mild left ventricular systolic dysfunction with apical hypokinesis (ejection fraction 50%). A repeat ECG showed new T-wave inversions compared to that from the time of admission. The patient eventually agreed to cardiac catheterization, which revealed patent vessels without coronary artery disease, supporting our diagnosis of Takotsubo syndrome and what is the first reported case of likely polidocanol-induced Takotsubo syndrome in the United States

Zircon U-Pb-Hf isotopes, bulk-rock geochemistry and Sr-Nd-Pb isotopes from late Neoproterozoic basement in the Mahneshan area, NW Iran: Implications for Ediacaran active continental margin along the northern Gondwana and constraints on the late Oligocene crustal anatexis

Available online 17 January 2018The Mahneshan granite intrusions and granodiorite-gneiss bodies in northwest Iran are part of the Takab magmatic–metamorphic complex, which includes numerous Precambrian continental crust that are now embedded in the Alpine-Himalayan orogenic system. The Mahneshan magmatic assemblage comprises of late Ediacaran-Cambrian gneiss and granites (531–576 Ma) and late Oligocene biotite (25.41 ± 0.4 Ma) granite intrusion. The late Oligocene granite has intruded into the Neoproterozoic sequences in this area. The bulk-rock geochemistry shows that the Ediacaran-Cambrian granitoids and gneisses are calc-alkaline and preserve arc-related signatures. The zircon Hf and bulk rock Sr-Nd-Pb isotopic data suggest that the Ediacaran-Cambrian granitoid plutons were generated via partial melting of continental crust. The late Oligocene granite is formed by the anatexis of Neoproterozoic igneous rocks due to crustal thickening. The whole rock Sr-Nd and zircon Hf isotopic values, Mesoproterozoic Nd and Hf model ages and the existence of inherited zircons suggest the involvement of older crustal components in the genesis of the Mahneshan Ediacaran-Cambrian granitoids. The late Neoproterozoic rock units in the Takab area together with other Ediacaran-Cambrian magmatic segments in Iran were part of the Cadomian active continental margin that were situated along the northern Gondwana margin during the Neoproterozoic. The geochemical trace elements reported from the upper Neoproterozoic-Cambrian plutons along the Cadomian fragments in Iran toward Turkey and Iberia show that most of these granitoid melts were generated in pressures less than garnet stability field suggesting the continental arc thickness less than those reported from the Andes. Furthermore, the Hf and Nd model ages from the Ediacaran-Cambrian Mahneshan intrusions suggest the existence of hidden Paleoproterozoic-Mesoproterozoic rocks in the lower continental crust of Iran.Maryam Honarmand, Wenjiao Xiao, Ghasem Nabatiand, Morgan L. Blades, Mozaniel C. dos Santos, Alan S. Collins, Songjian A