Journal articles: 'Splajn'

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Griffiths, B. J., D. T. Gawne, and G. Dong. "A Definition of the Topography of Grit-Blasted Surfaces for Plasma Sprayed Alumina Coatings." Journal of Manufacturing Science and Engineering 121, no. 1 (February 1, 1999): 49–53. http://dx.doi.org/10.1115/1.2830574.

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This paper describes the topographical implications of grit blasted surfaces on plasma sprayed alumina. The transition of the grit blasted surface from raw material to correctly blasted is described in terms of surface heights, height distribution, spacings and texture. The influence of embedded grit is shown to be significant. The individual particles of alumina impacting the surface are classified into two types, these being disc splats and splash splats. Their deposition relationships with regard to surface topography and adhesion is explained with reference to the two types of splat.

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Allard-Chamard, H., P. Dufort, and A. J. De Brum-Fernandes. "SOLUBLE PHOSPHOLIPASEA_2 IN THE LIFE AND DEATH OF OSTEOCLASTS." Clinical & Investigative Medicine 31, no. 4 (August 1, 2008): 1. http://dx.doi.org/10.25011/cim.v31i4.4785.

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Background: Prostaglandins are important for the control of bone remodeling; phospholipases A_2 are essential for prostaglandin synthesis and could be an important mediator for bone health. Our objective was to determine the role of sPLA_2 on osteoclastogenesis and osteoclast (OC) apoptosis. Methods: Human osteoclasts were differentiated in vitro from PBMC in the presence of RANKL and M-CSF. The presence of sPLA_2 was confirmed by immunohistochemistry in OCs in culture and on bone slices. The role of sPLA2 II on osteoclastogenesis and on OC apoptosis was studied using sPLA2 inhibitors The implication of sPLA2 II in bone remodeling in vivo was determined by comparing levels of the enzyme in the peripheral blood ofpatients with traumatic fracture compared to age- and sex-matched controls. Results: In vitrodifferentiated osteoclasts and in situ fetal and Pagetic bone osteoclasts express sPLA_2 II. sPLA_2II inhibition during osteoclastogenesis reduces the capacity to generateosteoclasts and increases apoptosis rate of osteoclastic precursors; it also induces apoptosis on mature OCs. Patients with bone fractures have significantly less circulating sPLA_2 II than controls. Conclusion: sPLA_2 II is present in OCs both invitro and in vivo, in normal as well as in pathologic situations. Its inhibition reduces osteoclastogenesis and increases apoptosis rate in vitro. Plasmatic sPLA_2 II levels are lower post-fracture than in controls. These results strongly suggest a role for sPLA2in the control of bone metabolism but the mechanisms implicated in this effects still need to be clarified.

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Cinca, Nuria, Antonio Isalgué, Javier Fernández, and S. Sampath. "NiTi Splat Features during Vacuum Thermal Spraying onto Several Substrates." Materials Science Forum 738-739 (January 2013): 357–61. http://dx.doi.org/10.4028/www.scientific.net/msf.738-739.357.

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Vacuum Plasma Spraying has been used to produce coatings onto steel substrates. This work deals with the study of splat morphology of the NiTi alloy sprayed by VPS onto different substrates (aluminium, copper, stainless steel, glass and alumina). All the previous characteristics are discussed in terms of wettability and thermal conductivities regarding the rapid cooling involved in the process. Although identical conditions were used during thermal spraying, a wide variety of splat formations were observed; commonly, slushy or splash/disc splats are formed depending on whether the particles have partially or fully melted. The thermal effusivity of the substrate material, which is a measure of its ability to exchange thermal energy with its surroundings, seems to play an important role promoting more or less spreading. The higher the thermal effusivity is, the more rapidly the splats are cooled, thus starting the solidification before they come to rest and, changing their morphology.

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Fukumoto, M., T. Yamaguchi, M. Yamada, and T. Yasui. "Splash Splat to Disk Splat Transition Behavior in Plasma-Sprayed Metallic Materials." Journal of Thermal Spray Technology 16, no. 5-6 (October 10, 2007): 905–12. http://dx.doi.org/10.1007/s11666-007-9083-y.

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Sanpo, Noppakun, and Jirasak Tharajak. "Influence of Feedstock Feed Rate on the Properties of SPPS-Deposited Cobalt Ferrite Splats." Applied Mechanics and Materials 866 (June 2017): 291–94. http://dx.doi.org/10.4028/www.scientific.net/amm.866.291.

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Cobalt ferrite sol-gel solution was deposited onto mild steel substrates to form single splats using a solution precursor plasma spray (SPPS) process. It was revealed that the thermal oxidation of cobalt and iron salts occurred mainly into six different formations of deposited splats. These formulations were cobalt monoxide (CoO), maghemite (γ-Fe2O3), cobalt oxide (Co3O4), cobalt oxyhydroxide (CoOOH), goethite (α-FeOOH), hematite (α-Fe2O3), magnetite (Fe3O4), and cobalt ferrite (CoFe2O4). The surface topographies of the splats exhibited burned, unmolten, partially molten, and completely molten splats. The feed rates of SPPS process played the important role on several properties of the splat such as splat morphologies and percentage of the obtained composite splat phases.

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Lahmar-Mebdoua, Y., A. Vardelle, Pierre Fauchais, and D. Gobin. "Heat Diffusion in Solidifying Alumina Splat Deposited on Solid Substrate under Plasma Sprayed Conditions: Application to Coating Formation." Defect and Diffusion Forum 297-301 (April 2010): 46–51. http://dx.doi.org/10.4028/www.scientific.net/ddf.297-301.46.

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A plasma-sprayed coating is built up by the layering of individual splats. The latter are formed by spreading and solidification of molten particles sprayed onto a solid substrate. The coating properties depend on its microstructure and the quality of contact between the splats and the underlying layer and between the piled-up splats. This work deals with a 1D model of heat transfer between plasma-sprayed alumina splat and smooth substrate. The model is based on heat diffusion in the solidifying splat and substrate and includes undercooling phenomenon, heterogeneous nucleation and crystal growth kinetics. It assumes that splat spreading and solidification are two independent processes. The model predicts splat cooling and solidification taking into account, as far as possible, the in-flight particle properties drawn from the literature in order to study their effect on splat thermal history. The effect of the quality of contact between the splats as well as the already-deposited and solidified layer thickness on the grain size distribution and front solidification velocity is investigated.

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Wei, Yulong, Lesan Yan, Lijun Luo, Tao Gui, Bian Jang, Ahmad Amirshaghaghi, Tianyan You, Andrew Tsourkas, Ling Qin, and Zhiliang Cheng. "Phospholipase A2 inhibitor–loaded micellar nanoparticles attenuate inflammation and mitigate osteoarthritis progression." Science Advances 7, no. 15 (April 2021): eabe6374. http://dx.doi.org/10.1126/sciadv.abe6374.

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Treating osteoarthritis (OA) remains a major clinical challenge. Despite recent advances in drug discovery and development, no disease-modifying drug for knee OA has emerged with any notable clinical success, in part, due to the lack of valid and responsive therapeutic targets and poor drug delivery within knee joints. In this work, we show that the amount of secretory phospholipase A2 (sPLA2) enzyme increases in the articular cartilage in human and mouse OA cartilage tissues. We hypothesize that the inhibition of sPLA2 activity may be an effective treatment strategy for OA. To develop an sPLA2-responsive and nanoparticle (NP)–based interventional platform for OA management, we incorporated an sPLA2 inhibitor (sPLA2i) into the phospholipid membrane of micelles. The engineered sPLA2i-loaded micellar NPs (sPLA2i-NPs) were able to penetrate deep into the cartilage matrix, prolong retention in the joint space, and mitigate OA progression. These findings suggest that sPLA2i-NPs can be promising therapeutic agents for OA treatment.

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MASUDA, Seiko, Makoto MURAKAMI, Michiko MITSUISHI, Kazuo KOMIYAMA, Yukio ISHIKAWA, Toshiharu ISHII, and Ichiro KUDO. "Expression of secretory phospholipase A2 enzymes in lungs of humans with pneumonia and their potential prostaglandin-synthetic function in human lung-derived cells." Biochemical Journal 387, no. 1 (March 22, 2005): 27–38. http://dx.doi.org/10.1042/bj20041307.

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Although a number of sPLA2 (secretory phospholipase A2) enzymes have been identified in mammals, the localization and functions of individual enzymes in human pathologic tissues still remain obscure. In the present study, we have examined the expression and function of sPLA2s in human lung-derived cells and in human lungs with pneumonia. Group IID, V and X sPLA2s were expressed in cultured human bronchial epithelial cells (BEAS-2B) and normal human pulmonary fibroblasts with distinct requirement for cytokines (interleukin-1β, tumour necrosis factor α and interferon-γ). Lentivirus- or adenovirus-mediated transfection of various sPLA2s into BEAS-2B or normal human pulmonary fibroblast cells revealed that group V and X sPLA2s increased arachidonate release and prostaglandin production in both cell types, whereas group IIA and IID sPLA2s failed to do so. Immunohistochemistry of human lungs with pneumonia demonstrated that group V and X sPLA2s were widely expressed in the airway epithelium, interstitium and alveolar macrophages, in which group IID sPLA2 was also positive, whereas group IIA sPLA2 was restricted to the pulmonary arterial smooth muscle layers and bronchial chondrocytes, and group IIE and IIF sPLA2s were minimally detected. These results suggest that group V and X sPLA2s affect lung pathogenesis by facilitating arachidonate metabolism or possibly through other functions.

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Shridas, Preetha, and Nancy R. Webb. "Diverse Functions of Secretory Phospholipases A2." Advances in Vascular Medicine 2014 (July 15, 2014): 1–11. http://dx.doi.org/10.1155/2014/689815.

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Phospholipase A2 enzymes (PLA2s) catalyze the hydrolysis of glycerophospholipids at their sn-2 position releasing free fatty acids and lysophospholipids. Mammalian PLA2s are classified into several categories of which important groups include secreted PLA2s (sPLA2s) and cytosolic PLA2s (cPLA2s) that are calcium-dependent for their catalytic activity and calcium-independent cytosolic PLA2s (iPLA2s). Platelet-activating factor acetylhydrolases (PAF-AHs), lysosomal PLA2s, and adipose-specific PLA2 also belong to the class of PLA2s. Generally, cPLA2 enzymes are believed to play a major role in the metabolism of arachidonic acid, the iPLA2 family to membrane homeostasis and energy metabolism, and the sPLA2 family to various biological processes. The focus of this review is on recent research developments in the sPLA2 field. sPLA2s are secreted enzymes with low molecular weight (with the exception of GIII sPLA2), Ca2+-requiring enzymes with a His-Asp catalytic dyad. Ten enzymatically active sPLA2s and one devoid of enzymatic activity have been identified in mammals. Some of these sPLA2s are potent in arachidonic acid release from cellular phospholipids for the biosynthesis of eicosanoids, especially during inflammation. Individual sPLA2 enzymes exhibit unique tissue and cellular localizations and specific enzymatic properties, suggesting their distinct biological roles. Recent studies indicate that sPLA2s are involved in diverse pathophysiological functions and for most part act nonredundantly.

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10

Chu, Xin, Phuong Vo, and Stephen Yue. "Investigation of the Splat Deposition Behavior onto a Composite Coating in Cold Spray." Materials Science Forum 941 (December 2018): 1639–44. http://dx.doi.org/10.4028/www.scientific.net/msf.941.1639.

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The splat test is usually generated by low feed rate cold spraying of particles onto an as-polished substrate and it can be considered as a monolayer coating deposition. In this study, in order to investigate cold spray deposition mechanisms, Fe splats were sprayed onto the cold-sprayed single component 316L, Fe, and a composite 90Fe coatings. Results showed that although there is only 3.6 vol.% of 316L in the composite 90Fe coating, Fe splats exhibit a much better deposition behavior onto the 90Fe as compared with the single component Fe coating. To explain this observation, Fe splat samples were characterized using the scanning electron microscope (SEM), optical profilometry, splat adhesion tests, and splat nanoindentation. Finally, a preliminary explanation towards the Fe splat deposition behavior onto the composite coating was drawn.

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Krizaj, Igor. "Roles of Secreted Phospholipases A2 in the Mammalian Immune System." Protein & Peptide Letters 21, no. 12 (November 5, 2014): 1201–8. http://dx.doi.org/10.2174/0929866521666140819122624.

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Secreted phospholipase A2 (sPLA2) molecules constitute a family of proteins that are involved functionally in many biological processes. In particular, they participate in diverse pathophysiological settings as enzymes that release free fatty acids and lysophospholipids from phospholipids in biological membranes, or as ligands for various cellular receptors. In this review the confirmed or expected functions of sPLA2s in the mammalian immune system are surveyed. Some of the twelve mammalian sPLA2 molecules constitute part of the so-called innate immune system by virtue of their antibacterial, antiviral and antifungal activities. They are also involved in acute inflammation, a protective reaction of the body to infection or injury. The acute inflammation sometimes escapes regulation, becomes chronic and can evolve into a severe pathology. One or more types of sPLA2 are involved in asthma, rheumatoid arthritis, sepsis, atherosclerosis, myocardial infarction, Crohn’s disease, ulcerative colitis and cancer. sPLA2s are thus important therapeutic targets as well as biotherapeutic molecules. Improving the selectivity of inhibitors of sPLA2s to be able to target a particular sPLA2 could therefore be one of the most important tasks for future research.

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Tillmann, W., O. Khalil, and I. Baumann. "Influence of Direct Splat-Affecting Parameters on the Splat-Type Distribution, Porosity, and Density of Segmentation Cracks in Plasma-Sprayed YSZ Coatings." Journal of Thermal Spray Technology 30, no. 4 (March 18, 2021): 1015–27. http://dx.doi.org/10.1007/s11666-021-01180-4.

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AbstractThe integrity and properties of ceramic coatings produced by atmospheric plasma spraying are highly controlled by the splat morphology and splat interconnection. In this study, the influence of selected parameters (spray angle, surface velocity of the spray gun, and substrate temperature) on splat morphology and coating microstructure was investigated. A favorite set of spray gun parameters, of which their effects on splat morphology and coating microstructure have been verified by previous experiments, were used to conduct the experiments for the present work. It was found that depositing fully molten particles on a hot substrate increases the fraction of disk-like splats by about 60% at the expense of the fraction of irregular splats. Preheating the substrate also increases the pore count and level of coating porosity, while it does not influence the density of segmentation cracks. In contrast, the surface velocity of the spray gun does not affect the splat morphology while a slow speed decreases the coating porosity and plays a significant role in generating segmentation cracks. Shifting the spray angle by 15° distorts up to 20% of disk-like splats and slightly decreases the porosity level. However, changing the spray angle does not affect the generation of segmentation cracks.

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13

Wei, Qiulan, Li He, Zhang Liu, Xiao Feng, and Ya-Zhe Xing. "The Morphology Analysis of Plasma-Sprayed Cast Iron Splats at Different Substrate Temperatures via Fractal Dimension and Circularity Methods." High Temperature Materials and Processes 38, no. 2019 (February 25, 2019): 692–98. http://dx.doi.org/10.1515/htmp-2019-0021.

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AbstractPlasma-sprayed cast iron splats were deposited onto polished aluminum substrates preheated to different temperatures ranging from 25°C to 250°C. The morphology of single splat was observed by a field emission scanning electron microscope. Quantitative characterization methods, including fractal dimension (FD) and circularity analyses of the splat profile, were employed to identify the difference in morphology of the splats with the change of the substrate temperature. The results showed that the substrate temperature has a significant effect on the spreading of molten droplets and the morphology of resultant splats through changing the solidification rate of the droplets. With the increment of substrate temperature, the homogeneous and sufficient spreading of the droplets resulted from low solidification rate reduces the splashing of the droplets. In addition, the evaporation of adsorbed moisture on the substrate improves the wettability between the spreading droplet and the substrate, then benefits the homogeneous spreading of the molten droplet. As a result, a distinct decline in the FD value was observed. It was also suggested that the FD analysis could be used to characterize the morphology of the splat more effectively while the circularity method was heavily dependent on the area of the splat.

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Mitsuishi, Michiko, Seiko Masuda, Ichiro Kudo, and Makoto Murakami. "Group V and X secretory phospholipase A2 prevents adenoviral infection in mammalian cells." Biochemical Journal 393, no. 1 (December 12, 2005): 97–106. http://dx.doi.org/10.1042/bj20050781.

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sPLA2 (secretory phospholipase A2) enzymes have been implicated in various biological events, yet their precise physiological functions remain largely unresolved. In the present study we show that group V and X sPLA2s, which are two potent plasma membrane-acting sPLA2s, are capable of preventing host cells from being infected with an adenovirus. Bronchial epithelial cells and lung fibroblasts pre-expressing group V and X sPLA2s showed marked resistance to adenovirus-mediated gene delivery in a manner dependent on their catalytic activity. Although adenovirus particles were insensitive to recombinant group V and X sPLA2s, direct addition of these enzymes to 293A cells suppressed both number and size of adenovirus plaque formation. Group V and X sPLA2s retarded the entry of adenovirus into endosomes. Moreover, adenoviral infection was suppressed by LPC (lysophosphatidylcholine), a membrane-hydrolytic product of these sPLA2s. Thus hydrolysis of the plasma membrane by these sPLA2s may eventually lead to the protection of host cells from adenovirus entry. Given that group V and X sPLA2s are expressed in human airway epithelium and macrophages and that the expression of endogenous group V sPLA2 is upregulated by virus-related stimuli in these cells, our present results raise the possibility that group V and X sPLA2s may play a role in innate immunity against adenoviral infection in the respiratory tract.

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Zhang, Xiao Feng, Ke Song Zhou, Xiao Ling Xiao, and Min Liu. "Failure Mechanism of 7YSZ Splat as Thermal Barrier Coating." Materials Science Forum 816 (April 2015): 219–25. http://dx.doi.org/10.4028/www.scientific.net/msf.816.219.

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An investigation of spallation behaviors of plasma-sprayed ZrO2-7wt.%Y2O3(7YSZ) splat at high temperature was carried out to understand the failure mechanism of thermal barrier coating (TBC). In present work, 7YSZ splats prepared by atmospheric plasma spray (APS) were collected on mirror polished NiCoCrAlYTa bond coating holding at 250 °C, where the nickel base superalloy K4169 was used as substrate. Then the samples with splats were taken into air furnace for isothermal oxidation test at 900 °C for different time. The surface of splat and cross section of splat-bond coating interface during isothermal test were characterized using a focused ion beam (FIB) assisted field emission scanning electron microscope (FE-SEM). Besides, the compositions of thermally grown oxide (TGO) layer at splat-bond coating interface were analyzed after oxidation test. In addition, the schematic diagram of spallation process and oxidation model of splat has been presented at relatively high temperature.

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Christerson, Ulrika, Åsa V. Keita, Martin E. Winberg, Johan D. Söderholm, and Christina Gustafson-Svärd. "Possible Involvement of Intracellular Calcium-Independent Phospholipase A2 in the Release of Secretory Phospholipases from Mast Cells—Increased Expression in Ileal Mast Cells of Crohn’s Disease." Cells 8, no. 7 (July 3, 2019): 672. http://dx.doi.org/10.3390/cells8070672.

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Increased activity of secretory phospholipases A2 (sPLA2) type-II was previously observed in ileum of Crohn’s disease (CD). Our aims were to explore the involvement of calcium-independent (i)PLA2β in the release of sPLA2s from the human mast cell (MC) line (HMC-1) and investigate expressions of cytosolic (c)PLA2α, iPLA2β, sPLA2-IIA and sPLA2-V in MCs of CD ileum. The release of sPLA2 was investigated in HMC-1 by immunocytochemistry and ELISA. The expression intensities of PLA2s in mucosal MCs, and the proportion of PLA2-positive MCs, were investigated in normal ileum and in ileum from patients with CD by immunohistochemistry. The calcium ionophore-stimulated release of sPLA2-IIA and sPLA2-V from HMC-1 was reduced by the iPLA2-inhibitor bromoenol lactone. All four PLA2s were detectable in mucosal MCs, both in normal ileum and in CD, but the proportion of iPLA2β-containing mucosal MCs and the expression intensity of sPLA2-IIA was increased in CD. Results indicate that iPLA2β is involved in the secretion of sPLA2s from HMC-1, and suggest that iPLA2β-mediated release of sPLA2 from intestinal MCs may contribute to CD pathophysiology. Ex vivo studies on isolated mucosal mast cells are however needed to clarify the precise role of MC PLA2s in the inflammatory processes of CD.

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Griffiths, B. J., D. T. Gawne, and G. Dong. "The role of grit blasting in the production of high-adhesion plasma sprayed alumina coatings." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 211, no. 1 (January 1, 1997): 1–9. http://dx.doi.org/10.1243/0954405971516022.

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This paper describes the adhesion mechanism of sprayed alumina particles on to grit-blasted surfaces. Two types of impacted particles are identified, these being disc and splash types of splats. The impact of the splats on various surfaces is identified which indicates why grit-blasted surfaces are considered the best. A series of surfaces has been prepared in which the alumina is built up to full coverage. The proportion of splats in the valleys, on flats and on peaks is identified for high-and low-adhesion samples. This is related to the definition of grit-blasted topography for manufacturing quality assurance.

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KAN KILINÇ, Betül, and Huruy DEBESSAY ASFHA. "Selection of Splines Models in the Presence of Multicollinearity and Outliers." Turkiye Klinikleri Journal of Biostatistics 12, no. 2 (2020): 183–92. http://dx.doi.org/10.5336/biostatic.2020-74122.

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19

NAKASHIMA, Satoru, Yutaka IKENO, Tatsuya YOKOYAMA, Masakazu KUWANA, Angelo BOLCHI, Simone OTTONELLO, Katsuhiko KITAMOTO, and Manabu ARIOKA. "Secretory phospholipases A2 induce neurite outgrowth in PC12 cells." Biochemical Journal 376, no. 3 (December 15, 2003): 655–66. http://dx.doi.org/10.1042/bj20030830.

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sPLA2s (secretory phospholipases A2) belong to a broad and structurally diverse family of enzymes that hydrolyse the sn-2 ester bond of glycerophospholipids. We previously showed that a secreted fungal 15 kDa protein, named p15, as well as its orthologue from Streptomyces coelicolor (named Scp15) induce neurite outgrowth in PC12 cells at nanomolar concentrations. We report here that both p15 and Scp15 are members of a newly identified group of fungal/bacterial sPLA2s. The phospholipid-hydrolysing activity of p15 is absolutely required for neurite outgrowth induction. Mutants with a reduced PLA2 activity exhibited a comparable reduction in neurite-inducing activity, and the ability to induce neurites closely matched the capacity of various p15 forms to promote fatty acid release from live PC12 cells. A structurally divergent member of the sPLA2 family, bee venom sPLA2, also induced neurites in a phospholipase activity-dependent manner, and the same effect was elicited by mouse group V and X sPLA2s, but not by group IB and IIA sPLA2s. Lysophosphatidylcholine, but not other lysophospholipids, nor arachidonic acid, elicited neurite outgrowth in an L-type Ca2+ channel activity-dependent manner. In addition, p15-induced neuritogenesis was unaffected by various inhibitors that block arachidonic acid conversion into bioactive eicosanoids. Altogether, these results delineate a novel, Ca2+- and lysophosphatidylcholine-dependent neurotrophin-like role of sPLA2s in the nervous system.

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Matache, Gheorghe, Cristian Puscasu, Alexandru Paraschiv, and Oana Trusca. "Investigation of some Intrinsic Properties of Thermal Sprayed Molybdenum Coatings for Railway Axle Applications." Applied Mechanics and Materials 811 (November 2015): 19–23. http://dx.doi.org/10.4028/www.scientific.net/amm.811.19.

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Thermal sprayed Mo coatings deposited on steel support deposited by electric arc and atmospheric plasma spray were investigated. Microstructural investigation of the coatings showed that in both variants the splats formed by rapid solidification and splashing during the impact with the substrate have irregular shape, exhibit cracks and scattered debris. The measured average equivalent diameter of the splats and the calculated average diameter of the particles that generated the splats are higher for electric arc spraying. Using the measured and calculated data it was descibed the relathionship between splats diameter, splats thickness and flattening degree. Some intrinsec properties of the coatings as roughness, hardness and bond strength were measured. All these properties are influenced by the splat size. Lower size of the splats lead to reduced surface roughness, higher hardness and higher bond strength of the coatings.

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Gross, Karlis A., Christiane Petzold, Liene Pluduma-LaFarge, Maris Kumermanis, and Håvard J. Haugen. "Structural and Chemical Hierarchy in Hydroxyapatite Coatings." Materials 13, no. 19 (October 7, 2020): 4447. http://dx.doi.org/10.3390/ma13194447.

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Hydroxyapatite coatings need similarly shaped splats as building blocks and then a homogeneous microstructure to unravel the structural and chemical hierarchy for more refined improvements to implant surfaces. Coatings were thermally sprayed with differently sized powders (20–40, 40–63 and 63–80 µm) to produce flattened homogeneous splats. The surface was characterized for splat shape by profilometry and Atomic force microscopy (AFM), crystal size by AFM, crystal orientation by X-ray diffraction (XRD) and structural variations by XRD. Chemical composition was assessed by phase analysis, but variations in chemistry were detected by XRD and Raman spectroscopy. The resulting surface electrical potential was measured by Kelvin probe AFM. Five levels of structural hierarchy were suggested: the coating, the splat, oriented crystals, alternate layers of oxyapatite and hydroxyapatite (HAp) and the suggested anion orientation. Chemical hierarchy was present over a lower range of order for smaller splats. Coatings made from smaller splats exhibited a greater electrical potential, inferred to arise from oxyapatite, and supplemented by ordered OH− ions in a rehydroxylated surface layer. A model has been proposed to show the influence of structural hierarchy on the electrical surface potential. Structural hierarchy is proposed as a means to further refine the properties of implant surfaces.

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Goldbaum, Dina, Richard R. Chromik, Nicolas Brodusch, and Raynald Gauvin. "Microstructure and Mechanical Properties of Ti Cold-Spray Splats Determined by Electron Channeling Contrast Imaging and Nanoindentation Mapping." Microscopy and Microanalysis 21, no. 3 (March 5, 2015): 570–81. http://dx.doi.org/10.1017/s1431927615000240.

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AbstractCold spray is a thermo-mechanical process where the velocity of the sprayed particles affects the deformation, bonding, and mechanical properties of the deposited material, in the form of splats or coatings. At high strain rates, the impact stresses are converted into heat, a phenomenon known as adiabatic shear, which leads to grain re-crystallization. Grain re-crystallization and growth are shown to have a direct impact on the mechanical properties of the cold-sprayed material. The present study ties the microstructural features within the cold-sprayed Ti splats and the substrate to the bonding mechanism and mechanical properties. High-resolution electron channeling contrast imaging, electron backscatter diffraction mapping, and nanoindentation were used to correlate the microstructure to the mechanical properties distribution within the titanium cold-spray splats. The formation of nanograins was observed at the titanium splat/substrate interface and contributed to metallurgical bonding. An increase in grain re-crystallization within the splat and substrate materials was observed with pre-heating of the substrate. In the substrate material, the predominant mechanism of deformation was twinning. A good relationship was found between the hardness and distribution of the twins within the substrate and the size distribution of the re-crystallized grains within the splats.

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Themsche, Céline Van, Michèle Jacob, and Christian Salesse. "Human retinal pigment epithelium secretes a phospholipase A2 and contains two novel intracellular phospholipases A2." Biochemistry and Cell Biology 79, no. 1 (January 1, 2001): 1–10. http://dx.doi.org/10.1139/o00-088.

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The sensitivity of different phospholipase A2 (PLA2)-active fractions eluted from cation-exchange chromatography to para-bromophenacylbromide (pBPB), Ca2+-EGTA, DTT, heat, and H2SO4 indicates that human cultured retinal pigment epithelial (hRPE) cells probably contain two different intracellular PLA2 enzymes. Control experiments using "back-and-forth" thin-layer chromatography confirmed that, in our assay conditions, the generation of free fatty acids originated solely from PLA2 activity. Together with immunoblot experiments where no cross-reactivity was observed between the hRPE cytosolic PLA2 enzymes and several antisera directed against secretory PLA2s (sPLA2s) and cytosolic PLA2 (cPLA2), these findings suggest that intracellular hRPE PLA2s are different from well-known sPLA2s, cPLA2, and Ca2+-independent PLA2s. We also report an additional hRPE-PLA2 enzyme that is secreted and that exhibits sensitivity to pBPB, Ca2+-EGTA, DTT, heat, and H2SO4, which is characteristic of sPLA2 enzymes. This approximately 22-kDa PLA2 cross-reacted weakly with an antiserum directed against porcine pancreatic group I sPLA2 but strongly with an antiserum directed against N-terminal residues 1-14 of human synovial group II sPLA2, suggesting that this extracellular enzyme is a member of the sPLA2 class of enzymes. We thus conclude that there are three distinct PLA2 enzymes in cultured hRPE cells, including two novel intracellular PLA2s and a 22-kDa secreted sPLA2 enzyme.Key words: phospholipase A2, retinal pigment epithelium, characterization.

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Zellma, Marek, and Agata Załęska-Fornal. "Application of B Splines to Identifi cation of the Movement Equations of the Floating Objects." Naše more 68, no. 1 (February 2021): 58–64. http://dx.doi.org/10.17818/nm/2021/1.7.

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The paper presents the possibilities of using B-splines to determine a mathematical model in the form of linear differential equations describing the change of the motion parameters of floating objects depending on the values of the control signals. The elaborated identification system is a collection of algorithms including: approximation of input and output signals, optimal selection of differential equation coefficients and model verification. The basic spline functions were used to approximate the values of the input and output signals. The developed method was illustrated by an example of identification of underwater submarine motion equations describing the change in draft depth and trim angle depending on the difference between buoyancy force and ship’s weight.

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Henderson, William R., Emil Y. Chi, James G. Bollinger, Ying-tzang Tien, Xin Ye, Luca Castelli, Yuri P. Rubtsov, et al. "Importance of group X–secreted phospholipase A2 in allergen-induced airway inflammation and remodeling in a mouse asthma model." Journal of Experimental Medicine 204, no. 4 (April 2, 2007): 865–77. http://dx.doi.org/10.1084/jem.20070029.

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Arachidonic acid metabolites, the eicosanoids, are key mediators of allergen-induced airway inflammation and remodeling in asthma. The availability of free arachidonate in cells for subsequent eicosanoid biosynthesis is controlled by phospholipase A2s (PLA2s), most notably cytosolic PLA2-α. 10 secreted PLA2s (sPLA2s) have also been identified, but their function in eicosanoid generation is poorly understood. We investigated the role of group X sPLA2 (sPLA2-X), the sPLA2 with the highest in vitro cellular phospholipolysis activity, in acute and chronic mouse asthma models in vivo. The lungs of sPLA2-X−/− mice, compared with those of sPLA2-X+/+ littermates, had significant reduction in ovalbumin-induced infiltration by CD4+ and CD8+ T cells and eosinophils, goblet cell metaplasia, smooth muscle cell layer thickening, subepithelial fibrosis, and levels of T helper type 2 cell cytokines and eicosanoids. These data direct attention to sPLA2-X as a novel therapeutic target for asthma.

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Herman, Herbert, Sanjay Sampath, and Robert McCune. "Thermal Spray: Current Status and Future Trends." MRS Bulletin 25, no. 7 (July 2000): 17–25. http://dx.doi.org/10.1557/mrs2000.119.

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Thermal spray is a continuous, directed, melt-spray process in which particles (e.g., 1–50 μm in diameter) of virtually any material are melted and accelerated to high velocities, through either a combustion flame or a dc or rf nontransferred thermal-plasma arc. The molten or semimolten droplets impinge on a substrate and rapidly solidify to form a thin “splat.” The deposit is built up by successive impingement and interbonding among the splats. The splats accumulate into a wellbonded deposit, generally > 10 μm thick.

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Muñoz-Sanjuán, Ignacio, and Ali H. Brivanlou. "Induction of Ectopic Olfactory Structures and Bone Morphogenetic Protein Inhibition by Rossy, a Group XII Secreted Phospholipase A2." Molecular and Cellular Biology 25, no. 9 (May 1, 2005): 3608–19. http://dx.doi.org/10.1128/mcb.25.9.3608-3619.2005.

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ABSTRACT The secreted phospholipases A2 (sPLA2s) comprise a family of small secreted proteins with the ability to catalyze the generation of bioactive lipids through glycophospholipid hydrolysis. Recently, a large number of receptor proteins and extracellular binding partners for the sPLA2s have been identified, suggesting that these secreted factors might exert a subset of their broad spectrum of biological activities independently of their enzymatic activity. Here, we describe an activity for the sPLA2 group XII (sPLA2-gXII) gene during Xenopus laevis early development. In the ectoderm, sPLA2-gXII acts as a neural inducer by blocking bone morphogenetic protein (BMP) signaling. Gain of function in embryos leads to ectopic neurogenesis and to the specification of ectopic olfactory sensory structures, including olfactory bulb and sensory epithelia. This activity is conserved in the Drosophila melanogaster, Xenopus, and mammalian orthologs and appears to be independent of the lipid hydrolytic activity. Because of its effect on olfactory neurogenesis, we have renamed this gene Rossy, in homage to the Spanish actress Rossy de Palma. We present evidence that Rossy/sPLA2-gXII can inhibit the transcriptional activation of BMP direct-target gene reporters in Xenopus and mouse P19 embryonic carcinoma cells through the loss of DNA-binding activity of activated Smad1/4 complexes. Collectively, these data represent the first evidence for signaling cross talk between a secreted phospholipase A2 and the BMP/transforming growth factor β pathways and identify Rossy/sPLA2-gXII as the only factor thus far described which is sufficient to induce anterior sensory neural structures during vertebrate development.

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Córdoba, Diego, and Tania Pernas-Castaño. "On the splash and splat singularities for the one-phase inhomogeneous Muskat Problem." Journal of Nonlinear Science 28, no. 6 (October 26, 2017): 2077–126. http://dx.doi.org/10.1007/s00332-017-9418-x.

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Hite, R. Duncan, Michael C. Seeds, Anca M. Safta, Randolph B. Jacinto, Julianna I. Gyves, David A. Bass, and B. Moseley Waite. "Lysophospholipid generation and phosphatidylglycerol depletion in phospholipase A2-mediated surfactant dysfunction." American Journal of Physiology-Lung Cellular and Molecular Physiology 288, no. 4 (April 2005): L618—L624. http://dx.doi.org/10.1152/ajplung.00274.2004.

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Pulmonary surfactant's complex mixture of phospholipids and proteins reduces the work of breathing by lowering alveolar surface tension during respiration. One mechanism of surfactant damage appears to be the hydrolysis of phospholipid by phospholipases activated in the inflamed lung. Humans have several candidate secretory phospholipase A2 (sPLA2) enzymes in lung cells and infiltrating leukocytes that could damage extracellular surfactant. We considered two mechanisms of surfactant disruption by five human sPLA2s, including generation of lysophospholipids and the depletion of specific phospholipids. All five sPLA2s studied ultimately caused surfactant dysfunction. Each enzyme exhibited a different pattern of hydrolysis of surfactant phospholipids. Phosphatidylcholine, the major phospholipid in surfactant and the greatest potential source for generation of lysophospholipids, was susceptible to hydrolysis by group IB, group V, and group X sPLA2s, but not group IIA or IID. Group IIA hydrolyzed both phosphatidylethanolamine and phosphatidylglycerol, whereas group IID was active against only phosphatidylglycerol. Thus, with groups IB and X, the generation of lysophospholipids corresponded with surfactant dysfunction. However, hydrolysis of and depletion of phosphatidylglycerol had a greater correlation with surfactant dysfunction for groups IIA and IID. Surfactant dysfunction caused by group V sPLA2 is less clear and may be the combined result of both mechanisms.

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Apichayakul, Pisit, Sittichai Wirojanupatump, and Sukanda Jiansirisomboon. "Correlations between In-Flight Particles, Splats and Coating Microstructures of Ni20Cr Thermally Sprayed by Flame and Arc Spray Processes." Materials Science Forum 534-536 (January 2007): 409–12. http://dx.doi.org/10.4028/www.scientific.net/msf.534-536.409.

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Correlations between in-flight particle, splat and coating microstructure of thermally sprayed Ni20Cr were investigated. Flame spray and arc spray systems were employed for spraying Ni20Cr powder and Ni20Cr wire, respectively. The results showed that the arc spray process produced a broader size distribution for both in-flight particles and splats compared to flame process. Flower-like splat morphology was obtained from the arc spray whereas a pancake-like splat was obtained by flame spray. Ni20Cr coating sprayed by arc process had a denser microstructure, lower porosity and better adhesion at the interface. This could be due to the higher temperature and velocity from the arc spray process enhancing the melting and adhering for coating formation.

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Leiguez, Elbio, Priscila Motta, Rodrigo Maia Marques, Bruno Lomonte, Suely Vilela Sampaio, and Catarina Teixeira. "A Representative GIIA Phospholipase A2 Activates Preadipocytes to Produce Inflammatory Mediators Implicated in Obesity Development." Biomolecules 10, no. 12 (November 24, 2020): 1593. http://dx.doi.org/10.3390/biom10121593.

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Adipose tissue secretes proinflammatory mediators which promote systemic and adipose tissue inflammation seen in obesity. Group IIA (GIIA)-secreted phospholipase A2 (sPLA2) enzymes are found to be elevated in plasma and adipose tissue from obese patients and are active during inflammation, generating proinflammatory mediators, including prostaglandin E2 (PGE2). PGE2 exerts anti-lipolytic actions and increases triacylglycerol levels in adipose tissue. However, the inflammatory actions of GIIA sPLA2s in adipose tissue cells and mechanisms leading to increased PGE2 levels in these cells are unclear. This study investigates the ability of a representative GIIA sPLA2, MT-III, to activate proinflammatory responses in preadipocytes, focusing on the biosynthesis of prostaglandins, adipocytokines and mechanisms involved in these effects. Our results showed that MT-III induced biosynthesis of PGE2, PGI2, MCP-1, IL-6 and gene expression of leptin and adiponectin in preadipocytes. The MT-III-induced PGE2 biosynthesis was dependent on cytosolic PLA2 (cPLA2)-α, cyclooxygenases (COX)-1 and COX-2 pathways and regulated by a positive loop via the EP4 receptor. Moreover, MT-III upregulated COX-2 and microsomal prostaglandin synthase (mPGES)-1 protein expression. MCP-1 biosynthesis induced by MT-III was dependent on the EP4 receptor, while IL-6 biosynthesis was dependent on EP3 receptor engagement by PGE2. These data highlight preadipocytes as targets for GIIA sPLA2s and provide insight into the roles played by this group of sPLA2s in obesity.

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Mukhia, Rajeev, Aruna Mukherjee, and Anjali Sabnis. "HISTOGENESIS OF HUMAN FETAL SPLEEN." International Journal of Anatomy and Research 4, no. 1 (March 31, 2016): 2119–24. http://dx.doi.org/10.16965/ijar.2016.159.

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Yang, Lian Wei, Jin Hui Li, Yun Dong, and Xiao Ping Lin. "Wear Performance of the Plasma Sprayed Fine WC-Co Composite Powders Coatings." Advanced Materials Research 454 (January 2012): 144–47. http://dx.doi.org/10.4028/www.scientific.net/amr.454.144.

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WC/Co; Composite coating; Plasma spraying; Friction and wear Abstract: WC- Co composite powders were synthesized by direct mechanical grinding in a rotary-vibration mill under 8h, and then analyzed by SEM and XRD. WC and WC/Co composite coatings were prepared by supersonic plasma spraying fine WC-Co composite powders. The wear and friction properties of both coatings were evaluated. The results showed that the wear resistance of the WC/Co composite coating was superior to that of the WC coating. The improvement in wear resistance of the WC/Co composite coating was attributed to its higher fracture toughness and adhesion strength as well as better thermal diffusivity. As for the WC/Co composite coating, the mechanism was mainly adhesion with micro-abrasion and fatigued-induced brittle fracture within splats, and the delamination along splat boundaries only occurred at high load. However, the failure of the WC coating was predominantly detachment of transferred film and brittle fracture within the splats and delamination along splat boundaries, which were enhanced with the increasing load.

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Oki, Sachio. "Relationship between Splat Morphology and Property of Plasma Sprayed Alumina Coatings." Materials Science Forum 449-452 (March 2004): 925–28. http://dx.doi.org/10.4028/www.scientific.net/msf.449-452.925.

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New method for characterization of coating microstructures and for evaluation of coating property by means of surface morphology has been proposed. In this paper, the distribution of shape and dimensions of splat was examined using quantitative analysis of scanning electron microscope images from the surface of spray pattern as well as the surface of coating. Results obtained in this study indicate that it is necessary to analyze the spray pattern as well as the surface morphology in order to estimate the coating property by means of the distribution of splat which composes the coating. Moreover, the splats, which are in the interface between the substrate and the coating, should have the same morphology as those of the coating surface. The relationship between splat morphology and the property of coatings was discussed.

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TAILOR, SATISH, N. Vashishtha, Ankur Modi, and SC Modi. "An Investigation on Splat and Flattening Behavior of Thermally Sprayed Copper on A Rough Surface: A New Approach." Journal of Thermal Spray and Engineering 2, no. 1 (2020): 37–42. http://dx.doi.org/10.52687/2582-1474/211.

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All thermal spray coatings are finally deposited on a rough and active grit-blasted surface of the job. But, available literatures are reporting splat and flattening behavior on a polished surface. There is a gap in thermal spraying to understand actual solidification on a rough surface. Therefore, in the present work an attempt has been made to study of splat formation of thermally sprayed copper onto grit-blasted rough surface. An optimization study is done to collect rounded/semi-rounded disk like splats to set spray parameters. Optimized parameters were also tested at four different gun traverse speeds to fabricate thin Cu coatings (30-50µm).

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Rizzo, Maria Teresa, Elisabeth Nguyen, Marlene Aldo-Benson, and Gerard Lambeau. "Secreted phospholipase A2 induces vascular endothelial cell migration." Blood 96, no. 12 (December 1, 2000): 3809–15. http://dx.doi.org/10.1182/blood.v96.12.3809.

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Abstract Secreted phospholipase A2 (sPLA2) regulates a variety of cellular functions. The present investigation was undertaken to elucidate the potential role of sPLA2 in endothelial cell (EC) migration. Bovine aortic endothelial cells (BAECs) exposed to sPLA2 placed in the lower compartment of a modified Boyden chamber displayed increased migration compared to cells exposed to vehicle. The effect of sPLA2 on EC migration was time and dose dependent. Migration of BAECs was observed at 30 minutes, increased over 1 to 2 hours, and declined thereafter. At 2 hours of stimulation, sPLA2 (0.01-2 μmol/L) induced 1.2- to 3-fold increased cell migration compared with media alone. Among the different sPLA2s tested, bee venom, Naja naja, and porcine and human pancreatic PLA2s all evoked a migratory response in ECs. Moreover, human synovial fluid, obtained from patients with arthritis and containing sPLA2 activity, induced EC migration. Migration of ECs was significantly reduced after exposure to a catalytic site mutant of pancreatic sPLA2with decreased lipolytic activity as compared to wild-type sPLA2. Similarly, pretreatment of human synovial fluid withp-bromophenacyl bromide, an irreversible inhibitor of sPLA2, markedly decreased the ability of human synovial fluid to stimulate EC migration. Moreover, migration of ECs was stimulated on exposure to hydrolytic products of sPLA2activity including arachidonic acid, lysophosphatidic acid, and lysophosphatidylcholine. These findings suggest that sPLA2plays a physiologic role in induction of EC migration. Moreover, the effects of sPLA2 on EC migration are mediated, at least in part, by its catalytic activity.

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Rizzo, Maria Teresa, Elisabeth Nguyen, Marlene Aldo-Benson, and Gerard Lambeau. "Secreted phospholipase A2 induces vascular endothelial cell migration." Blood 96, no. 12 (December 1, 2000): 3809–15. http://dx.doi.org/10.1182/blood.v96.12.3809.h8003809_3809_3815.

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Secreted phospholipase A2 (sPLA2) regulates a variety of cellular functions. The present investigation was undertaken to elucidate the potential role of sPLA2 in endothelial cell (EC) migration. Bovine aortic endothelial cells (BAECs) exposed to sPLA2 placed in the lower compartment of a modified Boyden chamber displayed increased migration compared to cells exposed to vehicle. The effect of sPLA2 on EC migration was time and dose dependent. Migration of BAECs was observed at 30 minutes, increased over 1 to 2 hours, and declined thereafter. At 2 hours of stimulation, sPLA2 (0.01-2 μmol/L) induced 1.2- to 3-fold increased cell migration compared with media alone. Among the different sPLA2s tested, bee venom, Naja naja, and porcine and human pancreatic PLA2s all evoked a migratory response in ECs. Moreover, human synovial fluid, obtained from patients with arthritis and containing sPLA2 activity, induced EC migration. Migration of ECs was significantly reduced after exposure to a catalytic site mutant of pancreatic sPLA2with decreased lipolytic activity as compared to wild-type sPLA2. Similarly, pretreatment of human synovial fluid withp-bromophenacyl bromide, an irreversible inhibitor of sPLA2, markedly decreased the ability of human synovial fluid to stimulate EC migration. Moreover, migration of ECs was stimulated on exposure to hydrolytic products of sPLA2activity including arachidonic acid, lysophosphatidic acid, and lysophosphatidylcholine. These findings suggest that sPLA2plays a physiologic role in induction of EC migration. Moreover, the effects of sPLA2 on EC migration are mediated, at least in part, by its catalytic activity.

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Ashford, Elizabeth. "A Response to Splawn." Utilitas 13, no. 3 (November 2001): 334–41. http://dx.doi.org/10.1017/s0953820800003216.

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I argue that Sider's view does succeed in accommodating the kind of maximization he is after, according to which the agent is required to maximize overall welfare with the single exception of his own welfare. I then argue that Splawn's argument highlights some interesting and important ways in which Sider's view fail to capture basic common-sense intuitions concerning the self-other asymmetry, but offer a different diagnosis of the source of the problem.

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Krishnasamy, Jayaprakash, Sathiskumar A. Ponnusami, Sergio Turteltaub, and Sybrand van der Zwaag. "Numerical Investigation into the Effect of Splats and Pores on the Thermal Fracture of Air Plasma-Sprayed Thermal Barrier Coatings." Journal of Thermal Spray Technology 28, no. 8 (November 13, 2019): 1881–92. http://dx.doi.org/10.1007/s11666-019-00949-y.

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Abstract The effect of splat interfaces on the fracture behavior of air plasma-sprayed thermal barrier coatings (APS-TBC) is analyzed using finite element modeling involving cohesive elements. A multiscale approach is adopted in which the explicitly resolved top coat microstructural features are embedded in a larger domain. Within the computational cell, splat interfaces are modeled as being located on a sinusoidal interface in combination with a random distribution of pores. Parametric studies are conducted for different splat interface waviness, spacing, pore volume fraction and fracture properties of the splat interface. The results are quantified in terms of crack nucleation temperature and total microcrack length. It is found that the amount of cracking in TBCs actually decreases with increased porosity up to a critical volume fraction. In contrast, the presence of splats is always detrimental to the TBC performance. This detrimental effect is reduced for the splat interfaces with high waviness and spacing compared to those with low waviness and spacing. The crack initiation temperature was found to be linearly dependent on the normal fracture properties of the splat interface. Insights derived from the numerical results aid in engineering the microstructure of practical TBC systems for improved resistance against thermal fracture.

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Fauchais, P., M. Vardelle, J. F. Coudert, A. Vardelle, C. Delbos, and J. Fazilleau. "Thermal plasma deposition from thick to thin coatings and from micro- to nanostructure." Pure and Applied Chemistry 77, no. 2 (January 1, 2005): 475–85. http://dx.doi.org/10.1351/pac200577020475.

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This paper is devoted to the presentation of our actual knowledge in plasma spraying. It presents successively: the parameters controlling the impact of the molten particles onto the substrate and resulting splat formation followed by splats layering and coating formation; the engineering of nano- or finely structured coatings with different possible routes; and the actual possibilities for the on-line control of the spray process.

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Waghmode, Ganesh Trimbak, Satishkumar Sukhanand Porwal, Pavankumar Bharat Shinde, and Uma Trimbak Waghmode. "MORPHOLOGICAL ANALYSIS OF VARIATIONS OF SPLEEN." International Journal of Anatomy and Research 5, no. 2.1 (April 30, 2017): 3693–97. http://dx.doi.org/10.16965/ijar.2017.143.

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Litvinov, V. A., I. I. Okseniuk, D. I. Shevchenko, V. T. Koppe, V. V. Bobkov, and V. M. Chornous. "SIMS Study of the Surface of TiFe Hydride Forming Alloy." Ukrainian Journal of Physics 62, no. 3 (March 2017): 195–201. http://dx.doi.org/10.15407/ujpe62.03.0195.

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Sato, Hiroyasu, Yoshitaka Taketomi, Yuki Isogai, Seiko Masuda, Tetsuyuki Kobayashi, Kei Yamamoto, and Makoto Murakami. "Group III secreted phospholipase A2 transgenic mice spontaneously develop inflammation." Biochemical Journal 421, no. 1 (June 12, 2009): 17–27. http://dx.doi.org/10.1042/bj20082429.

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PLA2 (phospholipase A2) group III is an atypical sPLA2 (secretory PLA2) that is homologous with bee venom PLA2 rather than with other mammalian sPLA2s. In the present paper, we show that endogenous group III sPLA2 (PLA2G3) is expressed in mouse skin and that Tg (transgenic) mice overexpressing human PLA2G3 spontaneously develop skin inflammation. Pla2g3-Tg mice over 9 months of age frequently developed dermatitis with hyperkeratosis, acanthosis, parakeratosis, erosion, ulcer and sebaceous gland hyperplasia. The dermatitis was accompanied by infiltration of neutrophils and macrophages and by elevated levels of pro-inflammatory cytokines, chemokines and prostaglandin E2. In addition, Pla2g3-Tg mice had increased lymph aggregates and mucus in the airway, lymphocytic sialadenitis, hepatic extramedullary haemopoiesis, splenomegaly with increased populations of granulocytes and monocytes/macrophages, and increased serum IgG1. Collectively, these observations provide the first demonstration of spontaneous development of inflammation in mice with Tg overexpression of mammalian sPLA2.

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Azarmi, F., A. Moradian, J. Mostaghimi, Tom W. Coyle, and L. Pershin. "Microstructure Characterization and Modeling of Splat Formation during Air Plasma Spraying for Inconel 625 Superalloy." Materials Science Forum 539-543 (March 2007): 1218–23. http://dx.doi.org/10.4028/www.scientific.net/msf.539-543.1218.

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There is a growing interest in use of the nickel-based alloy Inconel 625 coatings due to its ability to improve base materials high temperature properties. Thermal spraying methods such as Air Plasma Spraying (APS) can be considered as a convenient method to deposit this material. The present work deals with APS deposited Inconel 625 structures consisting of huge number of individual splats formed by impacting molten droplets on substrates during spraying process. It is clear that the splat formation mechanism which dominates its size, cohesion, and boundaries highly influences the microstructure of the coating. This paper presents a developed numerical technique performed to simulate splat formation using a three dimensional model. In this method flow field is solved by Finite Volume Method (FVM) and free surfaces are determined from Youngs’ Volume of Fraction method (VOF). Finally, the model prediction is correlated with the actual splat geometries.

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Lewin, Matthew, José Gutiérrez, Stephen Samuel, María Herrera, Wendy Bryan-Quirós, Bruno Lomonte, Philip Bickler, Tommaso Bulfone, and David Williams. "Delayed Oral LY333013 Rescues Mice from Highly Neurotoxic, Lethal Doses of Papuan Taipan (Oxyuranus scutellatus) Venom." Toxins 10, no. 10 (September 20, 2018): 380. http://dx.doi.org/10.3390/toxins10100380.

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There is an unmet need for economical snakebite therapies with long shelf lives that are effective even with delays in treatment. The orally bioavailable, heat-stable, secretory phospholipase A2 (sPLA2) inhibitor, LY333013, demonstrates antidotal characteristics for severe snakebite envenoming in both field and hospital use. A murine model of lethal envenoming by a Papuan taipan (Oxyuranus scutellatus) demonstrates that LY333013, even with delayed oral administration, improves the chances of survival. Furthermore, LY333013 improves the performance of antivenom even after it no longer reverses neurotoxic signs. Our study is the first demonstration that neurotoxicity from presynaptic venom sPLA2S can be treated successfully, even after the window of therapeutic antivenom has closed. These results suggest that sPLA2 inhibitors have the potential to reduce death and disability and should be considered for the initial and adjunct treatment of snakebite envenoming. The scope and capacity of the sPLA2 inhibitors ability to achieve these endpoints requires further investigation and development efforts.

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van Dinter, M., and W. K. van Zijverden. "Settlement and land use on crevasse splay deposits; geoarchaeological research in the Rhine-Meuse Delta, the Netherlands." Netherlands Journal of Geosciences - Geologie en Mijnbouw 89, no. 1 (July 2010): 21–34. http://dx.doi.org/10.1017/s0016774600000792.

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AbstractUntil recently, most archaeologists assumed that human occupation of the Dutch river area in the Neolithic period and Bronze Age was rare and predominantly seasonal. Settlement and land use were thought to be limited to abandoned alluvial ridges and aeolian dunes. However, recent archaeological research revealed that Neolithic and Bronze Age human activity occurred at many locations in the Rhine-Meuse Delta. Human settlement and agricultural land use in the Rhine-Meuse delta from at least 3200 BC to 1100 AD was much more common than previously thought. Crevasse splay complexes of active and abandoned river systems proved to have provided favourable sites for settlements. These elevated areas were suitable for agriculture, as they were fertile, easy to plough and possessed suitable hydrological conditions. In addition, people could exploit the surrounding floodplain for hunting, fishing or herding their cattle. Furthermore, the river or residual river channel was near for transport. From the start of the Middle Bronze Age B (1400 BC) occupation of crevasse splay deposits in the delta was widespread. Farmsteads were built on splays that varied in size and morphology. Some locations were abandoned after a few decades, while others remained occupied during a much longer period. During the period of occupation, the crevasse splays gradually lost their relatively high position in the landscape due to subsidence and ongoing sedimentation on the floodplain.LIDAR data combined with digital coring databases and/or detailed soil maps have proven to be an excellent method to identify and map crevasse splays and archaeological sites on these. The resulting new maps form a major basis for archaeological prospection and preservation policy.

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Coutand, Daniel, and Steve Shkoller. "On the Finite-Time Splash and Splat Singularities for the 3-D Free-Surface Euler Equations." Communications in Mathematical Physics 325, no. 1 (December 5, 2013): 143–83. http://dx.doi.org/10.1007/s00220-013-1855-2.

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Maled, Venkatesh. "Accessory Spleen at Autopsy: An Incidental Finding." Indian Journal of Forensic Medicine and Pathology 9, no. 4 (2016): 235–37. http://dx.doi.org/10.21088/ijfmp.0974.3383.9416.7.

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Giannotti, Karina Cristina, Sönke Weinert, Mariana Nascimento Viana, Elbio Leiguez, Thaís L. S. Araujo, Francisco R. M. Laurindo, Bruno Lomonte, Rüdiger Braun-Dullaeus, and Catarina Teixeira. "A Secreted Phospholipase A2 Induces Formation of Smooth Muscle Foam Cells Which Transdifferentiate to Macrophage-Like State." Molecules 24, no. 18 (September 6, 2019): 3244. http://dx.doi.org/10.3390/molecules24183244.

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Vascular smooth muscle cells (VSMCs) loaded with lipid droplets (LDs) are markers of atherosclerosis. In this disease, inflammatory Group IIA-secreted phospholipase A2s (GIIA sPLA2s) are highly expressed in VSMCs, but their actions in these cells are unknown. Here, we investigated the ability of myotoxin III (MT-III), an ophidian GIIA sPLA2 sharing structural and functional features with mammalian GIIA sPLA2s, to induce LD formation and lipid metabolism factors involved in this effect. Modulation of VSMC phenotypes by this sPLA2 was also evaluated. Incubation of VSMCs with MT-III significantly increased the number of LDs. MT-III upregulated scavenger receptor type 1 (SR-A1) and lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) protein expression and enhanced acetylated-low density lipoprotein (acLDL) uptake by VSMCs, revealing the ability of a GIIA PLA2 to modulate scavenger receptor activities. MT-III induced translocation and protein expression of PPAR-γ and -β/δ. Inhibition of peroxisome proliferator-activated receptors (PPARs) and diacylglycerol O-acyltransferase (DGAT) and acyl-CoA:cholesterolacyltransferase (ACAT) enzymes abrogated MT-III-induced LD formation. Moreover, in response to MT-III, VSMCs acquired phagocytic activity and expressed macrophage markers CD68 and MAC-2. In conclusion, MT-III is able to stimulate VSMCs and recruit factors involved in lipid uptake and metabolism, leading to the formation of VSMC-derived foam cells with acquisition of macrophage-like markers and functions.

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Singh, Jaswinder Pal, Wolf-Dietrich Weber, and Anoop Gupta. "SPLASH." ACM SIGARCH Computer Architecture News 20, no. 1 (March 1992): 5–44. http://dx.doi.org/10.1145/130823.130824.

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Journal articles on the topic 'Splajn'

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