bluuebunny/crossref_metadata_2025_split huggingface dataset:
Integrated CO2-H2S corrosion-erosion modeling in gas production tubing and pipeline by considering passive layer activity
Authors: Rahmawati Silvya Dewi , Santoso Ryan Kurniawan , Tanjungsari Fadhila 
Published: July 2021

AbstractCorrosion and erosion are the common pipe-integrity issues that occur when carbon dioxide, hydrogen sulfide and sand exist in the gas stream at the same time. Corrosion is developed by the reaction among carbon dioxide, hydrogen sulfide and iron, while erosion by the physical damage through flowing sand. When it comes to the prediction model which could accommodate both events, complex phenomena related to physics, chemistry and metallurgy should be put into account. In this paper, we develop a new-integrated corrosion-erosion model which can calculate the corrosion-erosion rate by considering the interactions among type of passive layer (mackinawite and siderite), formation and removal rate of passive layer, and surface reaction rate. The integrated model consists of fluid flow in pipes equation, kinetics of reaction, fundamental diffusion law, empirical erosion equation and fundamental Faraday’s law. Corrosion-erosion rate is obtained through iteration scenario after establishing pressure and temperature from fluid flow in pipes equation. Pipe dimension used in the simulation has tubing ID 2.992 in for vertical pipe and flowline ID 2.992 in for horizontal pipe. Simulations were conducted using hypothetic gas field data with variation of hydrogen sulfide and carbon dioxide composition. In constant erosion rate, when the hydrogen sulfide percentage is significantly greater than carbon dioxide, corrosion is more dominant than passive layer formation. However, when the carbon dioxide percentage is greater than that of hydrogen sulfide, the passive layer tends to form, resulting in scaling. These results can be explained by the faster formation rate of siderite than mackinawite. Finally, the proposed model can explain clearly the phenomena of corrosion-erosion and scaling by simplifying the complex phenomena occurred.
Effect of PMMA Removal Methods on Opto-Mechanical Behaviors of Optical Fiber Resonant Sensor With Graphene Diaphragm
Authors: Liu Yujian , Li Cheng , Fan Shangchun , Song Xuefeng 
Published: July 2021

AbstractRegarding the dependence of the treatment of removing polymethyl methacrylate (PMMA) from graphene upon the prestress in the film, two typical PMMA removal methods including acetone-vaporing and high-temperature annealing were investigated based on the opto-mechanical behaviors of the developed optical fiber Fabry-Perot (F-P) resonant sensor with a 125-µm diameter and ∼10-layer-thickness graphene diaphragm. The measured resonant responses showed that the F-P sensor via annealing process exhibited the resonant frequency of 481 kHz and quality factor of 1 034 at ∼2 Pa and room temperature, which are respectively 2.5 times and 33 times larger than the acetone-treated sensor. Moreover, the former achieved a high sensitivity of 110.4 kHz/kPa in the tested range of 2 Pa–2.5 kPa, apparently superior to the sensitivity of 16.2 kHz/kPa obtained in the latter. However, the time drift of resonant frequency also mostly tended to occur in the annealed sensor, thereby shedding light on the opto-mechanical characteristics of graphene-based F-P resonant sensors, along with an optimized optical excitation and detection scheme.
Zur Fragilität von Gemeinschaft und Inklusion
Authors: Bossen Andrea , Merl Thorsten 
Published: July 2021

ZusammenfassungGemeinschaft und Inklusion sind schillernde, pädagogisch-normative Grundbegriffe, die beide in ihrem Kern auf etwas Gemeinsames rekurrieren, das mehr ist als die bloße Kopräsenz, zugleich aber häufig ungeklärt bleiben. Darüber hinaus ist bisher nicht geklärt worden, in welchem Verhältnis diese beiden Grundbegriffe zueinander stehen. In Abgrenzung zu programmatischen Bestimmungen fragt der vorliegende Beitrag empirisch rekonstruktiv, wie im Unterricht einer sich neu konstituierenden inklusiven Grundschulklasse Gemeinsames aufgerufen wird, welche Ideen von Gemeinschaft sich dadurch entfalten und wie sich dies zu schulischer Inklusion verhält. Deutlich wird, dass verschiedene Gemeinschaften imaginiert werden, die insofern fragil sind, als sie mit diffusen Erwartungen gefüllt und paradoxerweise zugleich als „schon da“ und „noch herzustellen“ thematisiert werden. Diese fragile Konstruktion hat ebenso Auswirkungen auf den tendenziellen Widerspruch von Inklusion und Gemeinschaft, der sich in unserer Analyse zeigt.
Spatial and Temporal Trends in the Economic Value of Biotic Pollination Services in Georgia, USA: 2009–2017
Authors: Pless Rachel , Ferreira Susana , Bergstrom John , Rabinowitz Adam N. 
Published: July 2021

AbstractUsing a production function approach, we estimate that the economic value of biotic pollination to Georgia’s agriculture increased from $425 million in 2009 to $488 million in 2017 in real terms. We perform spatial analysis to reveal county-level spatial patterns and temporal trends in that value. Using a unique set of pollinator survey data, we also compare the locations of biotic pollinators to the areas they bring the most economic value to, which provides insights on the variation in the dependency of the crop mix to pollination services.
Classification of environmental factors potentially motivating for dairy cows to access shade
Authors: Deniz Matheus , de Sousa Karolini Tenffen , Gomes Isabelle Cordova , Vale Marcos Martinez do , Dittrich João Ricardo 
Published: July 2021

AbstractThe aim of this Research Communication was to apply the data mining technique to classify which environmental factors have the potential to motivate dairy cows to access natural shade. We defined two different areas at the silvopastoral system: shaded and sunny. Environmental factors and the frequency that dairy cows used each area were measured during four days, for 8 h each day. The shaded areas were the most used by dairy cows and presented the lowest mean values of all environmental factors. Solar radiation was the environmental factor with most potential to classify the dairy cow's decision to access shaded areas. Data mining is a machine learning technique with great potential to characterize the influence of the thermal environment in the cows' decision at the pasture.
Building Britannia: Pre-Flavian Private and Public Construction across Southern Britain
Authors: Fulford Michael , Machin Sara 
Published: July 2021

ABSTRACTExcavation of the Roman tilery at Little London, Pamber, Hampshire, has prompted a reassessment of the dating of relief-patterned tile, assigning the bulk of production to the Claudio-Neronian period rather than the late first to mid-/late second century. This material has been privileged for retention in excavation archives but can now be seen as a proxy for the manufacture of a much wider range of ceramic building material, typically discarded on site, which, in the case of products from Little London and pre-Flavian Minety (Wiltshire), travelled distances of up to 100 km. Redating implies more extensive public and private building in town and country south and east of the Fosse Way before the Flavian period than has previously been envisaged. While private building included the construction of bath-houses, heated rooms and the provision of roofing materials, public building, we suggest, provided tabernas et praetoria along the principal roads of the province. In the private sphere such building provides a possible context for Dio Cassius’ mention of the recall and confiscation of large loans made to Britons before the Boudican rebellion. Finally, consideration of fabric needs to be added to the criteria for retaining ceramic building material in excavation archives.
Analysis of exit probability for a trajectory tracking robot in case of a rare event
Authors: Rana Rohit , Gaur Prerna , Agarwal Vijyant , Parthasarathy Harish 
Published: July 2021

AbstractIn this paper, a novel statistical application of large deviation principle (LDP) to the robot trajectory tracking problem is presented. The exit probability of the trajectory from stability zone is evaluated, in the presence of small-amplitude Gaussian and Poisson noise. Afterward, the limit of the partition function for the average tracking error energy is derived by solving a fourth-order system of Euler–Lagrange equations. Stability and computational complexity of the proposed approach is investigated to show the superiority over the Lyapunov method. Finally, the proposed algorithm is validated by Monte Carlo simulations and on the commercially available Omni bundleTM robot.
Back to the Coordinated Attack Problem
Authors: Godard Emmanuel , Perdereau Eloi 
Published: July 2021

AbstractWe consider the well-known Coordinated Attack Problem, where two generals have to decide on a common attack, when their messengers can be captured by the enemy. Informally, this problem represents the difficulties to agree in the presence of communication faults. We consider here only omission faults (loss of message), but contrary to previous studies, we do not to restrict the way messages can be lost, i.e., we make no specific assumption, we use no specific failure metric. In the large subclass of message adversaries where the double simultaneous omission can never happen, we characterize which ones are obstructions for the Coordinated Attack Problem. We give two proofs of this result. One is combinatorial and uses the classical bivalency technique for the necessary condition. The second is topological and uses simplicial complexes to prove the necessary condition. We also present two different Consensus algorithms that are combinatorial (resp. topological) in essence. Finally, we analyze the two proofs and illustrate the relationship between the combinatorial approach and the topological approach in the very general case of message adversaries. We show that the topological characterization gives a clearer explanation of why some message adversaries are obstructions or not. This result is a convincing illustration of the power of topological tools for distributed computability.
Lithospheric Structure Near the Northern Xainza‐Dinggye Rift, Tibetan Plateau–Implications for Rheology and Tectonic Dynamics
Authors: Sheng Yue , Jin Sheng , Comeau Matthew J. , Dong Hao , Zhang Letian , Lei Lulu , Li Baochun , Wei Wenbo , Ye Gaofeng , Lu Zhanwu 
Published: July 2021

AbstractThe Xainza‐Dinggye rift, an approximately north‐south trending Cenozoic fault zone across the Lhasa Terrane, is an ideal location to investigate extensional mechanisms in the upper crust and lithospheric deformation caused by the subducting Indian Plate beneath the central‐southern Tibetan Plateau. The 3‐D electrical resistivity structure was obtained by modeling magnetotelluric data from an array across the rift zone. Using the temperature distribution throughout the crust combined with the pressure and water content, we compute the pure melt conductivity. This enables estimation of the partial melt fraction of large‐area conductive zones imaged throughout the crust, and thus allows their rheology and strength to be evaluated. The heterogeneous distribution of high melt fraction areas in the crust has implications for the local continuous migration of fluids in the east‐west direction. The electrical structure also reveals a dipping resistive zone beneath the Tethys‐Himalaya terrane that represents the subducted Indian Plate. Significantly, its depth is observed to vary substantially from east (deeper) to west (shallower), which may indicate tearing of the plate. We suggest that the cause of extension and the formation of the crustal rift zone is related to tearing of the plate directly below this location, and the subsequent partial melting of the mid‐lower crust. Furthermore, the ascent of deep hydrothermal fluids, and heating of the shallow subsurface, likely led to the formation of the congruent Xainza‐Dinggye Thermal Belt. Additionally, the emplacement of numerous adjacent magmatic‐hydrothermal ore deposits is also likely related to partial melting and hydrothermal fluid migration in the crust.
Constraining Global Marine Iron Sources and Ligand‐Mediated Scavenging Fluxes With GEOTRACES Dissolved Iron Measurements in an Ocean Biogeochemical Model
Authors: Somes Christopher J. , Dale Andrew W. , Wallmann Klaus , Scholz Florian , Yao Wanxuan , Oschlies Andreas , Muglia Juan , Schmittner Andreas , Achterberg Eric P. 
Published: July 2021

AbstractIron is a key micronutrient controlling phytoplankton growth in vast regions of the global ocean. Despite its importance, uncertainties remain high regarding external iron source fluxes and internal cycling on a global scale. In this study, we used a global dissolved iron data set, including GEOTRACES measurements, to constrain source and scavenging fluxes in the marine iron component of a global ocean biogeochemical model. Our model simulations tested three key uncertainties: source inputs of atmospheric soluble iron deposition (varying from 1.4 to 3.4 Gmol/yr), reductive sedimentary iron release (14–117 Gmol/yr), and compared a variable ligand parameterization to a constant distribution. In each simulation, scavenging rates were tuned to reproduce the observed global mean iron inventory for consistency. The variable ligand parameterization improved the global model‐data misfit the most, suggesting that heterotrophic bacteria are an important source of ligands to the ocean. Model simulations containing high source fluxes of atmospheric soluble iron deposition (3.4 Gmol/yr) and reductive sedimentary iron release (114 Gmol/yr) further improved the model most notably in the surface ocean. High scavenging rates were then required to maintain the iron inventory resulting in relatively short surface and global ocean residence times of 0.83 and 7.5 years, respectively. The model simulates a tight spatial coupling between source inputs and scavenging rates, which may be too strong due to underrepresented ligands near source inputs, contributing to large uncertainties when constraining individual fluxes with dissolved iron concentrations. Model biases remain high and are discussed to help improve global marine iron cycle models.
Southern Ocean Phytoplankton Community Structure as a Gatekeeper for Global Nutrient Biogeochemistry
Authors: Nissen Cara , Gruber Nicolas , Münnich Matthias , Vogt Meike 
Published: July 2021

AbstractUpwelling and the biological pump in the Southern Ocean control the amount and stoichiometry of nutrients available for lateral export to lower latitudes, thereby collectively acting as a gatekeeper for the global thermocline nutrient distribution and global ocean productivity. Yet, the exact role played by phytoplankton and its community composition in this gatekeeping has not been well established. Here, we investigate this role using a high‐resolution model of the Southern Ocean (ROMS‐BEC) with an explicit parametrization of silicifying diatoms and calcifying coccolithophores. Consistent with expectations, diatoms are very efficient in consuming the upwelled Si south of the Antarctic Polar Front, and exporting it to depth at a rate of 91 Tmol Si . This leads to Si being trapped in the Southern Ocean, preventing it from leaking laterally into the Subantarctic. Model experiments reveal that this trapping is driven by both high Si‐to‐N diatom uptake ratios and the relatively slow dissolution of the exported opal, with the latter being the dominant mechanism. The low consumption resulting from this high uptake ratio allows a good fraction of the upwelled to reach the Subantarctic where it fuels the growth of a mixed community including coccolithophores. Coccolithophore production and export of calcite at a rate of 0.16 Pg C facilitates an efficient transfer of the exported organic matter to depth, thereby further modifying the laterally exported nutrient levels and stoichiometry. Our results thus demonstrate a key role of phytoplankton community structure in controlling the Southern Ocean biogeochemical gate.
Wavenumber‐4 Patterns of the Sporadic E Over the Middle‐ and Low‐Latitudes
Authors: Liu Zhendi , Fang Hanxian , Yue Xinan , Lyu Huijuan 
Published: July 2021

AbstractThe COSMIC radio occultation observations are used to investigate the wavenumber‐4 (WN4) structure of the Sporadic E (Es) layer during 2007–2018. The WN4 pattern is observed in the Es occurrence rate over the middle‐ and low‐latitudes. This pattern is stronger at the low‐latitudes than at the middle‐latitudes. It shows the peak intensity in latitude bands between 5° and 15° dip latitudes in both hemispheres. The WN4 structure occurs predominantly during daytime. It appears above 110 km in the morning, then descends slowly down to about 105 km, and finally disappears after sunset. The WN4 structure moves eastward with a speed of approximately 90°/day. It is prominent in boreal autumn and summer, and disappears in boreal winter. The dominant role of the DE3 tide for the formation of the WN4 structure is supported by similar features between the Es occurrence rate and the DE3 tide of the zonal wind shear, such as the phase, eastward speed, seasonal variation, symmetrical distribution, and strong activity at the low‐latitudes.
Micromagnetic Calculations of the Effect of Magnetostatic Interactions on Isothermal Remanent Magnetization Curves: Implications for Magnetic Mineral Identification
Authors: Bai Fan , Chang Liao , Berndt Thomas A. , Pei Zhaowen 
Published: July 2021

AbstractIsothermal remanent magnetization (IRM) curves are used widely in rock magnetic and environmental magnetic studies to characterize magnetic properties of natural samples. Previous theoretical and experimental investigations indicate that magnetostatic interactions can strongly affect the IRM behavior. In order to quantitatively investigate this effect, we modeled IRM curves and hysteresis properties for magnetite assemblages with variable morphologies (grain size, elongation, and shape) using the finite‐element micromagnetic modeling code MERRILL. We also conducted an analytical study of IRM behavior for noninteracting single domain grains utilizing the Stoner–Wohlfarth model. It is found that multiple Gaussian components do not necessarily reflect multiple magnetic mineral populations. For example, magnetostatic interactions can produce coercivity distributions that resemble results of some samples containing a detrital and extracellular (D + EX) and a biogenic soft or hard (BS/BH) coercivity components. Simulated IRM curves for different morphologies of interacting flattened grains are similar, indicating that the effect of interactions can overshadow the effect of grain morphologies. Moreover, our micromagnetic and analytical calculations consistently indicate that the IRM curves for noninteracting fine‐grained assemblages are mostly determined by grain shape (elongated or flattened) and elongation distributions of the magnetic mineral assemblages. Our simulations present possible outcome of IRM curves for magnetic mineral assemblages with controlled grain size, shape and microstructures, which provides important theoretical constraints on characterizing complex magnetic mineral components in natural samples through IRM curves and hysteresis.
LncRNA RCAT1 promotes tumor progression and metastasis via miR-214-5p/E2F2 axis in renal cell carcinoma
Authors: Guo Renbo , Zou Benkui , Liang Yiran , Bian Jiasheng , Xu Jian , Zhou Qian , Zhang Chao , Chen Tao , Yang Mingshan , Wang Huansheng , Pei Fajun , Xu Zhonghua 
Published: July 2021

AbstractRenal cell carcinoma is the second malignant tumors in the urinary system with high mortality and morbidity. Increasing evidence suggests that long non-coding RNAs (lncRNAs) play critical roles in tumor development and progression. In the current study, based on the publicly available data obtained from GEO and TCGA database, we identified five prognosis-related lncRNAs with the ability to predict the prognosis of patients with renal cell carcinoma. Among them, the uncharacterized and upregulated lncRNA RCAT1 (renal cancer-associated transcript 1) was identified as the key lncRNA. Our data further revealed that the expression of lncRNA RCAT1 was significantly upregulated in renal cell carcinoma tissues and cells. Gain-of-function and loss-of-function studies showed that lncRNA RCAT1 promoted cell proliferation, migration, and invasion in vitro and in vivo. Furthermore, we verified that lncRNA RCAT1 could abundantly sponge miR-214-5p, which served as a tumor suppressor in renal cell carcinoma. Significantly, miR-214-5p overexpression could attenuate the promotion of cell proliferation and metastasis induced by lncRNA RCAT1. Moreover, we found that E2F2 was a direct target of miR-214-5p, and lncRNA RCAT1 could protect E2F2 from miR-214-5p-mediated degradation. Taken together, our findings suggested that lncRNA RCAT1 could enhance the malignant phenotype of renal cell carcinoma cells by modulating miR‐214‐5p/E2F2 axis, and lncRNA RCAT1 might be a novel prognostic biomarker and a potential therapeutic target for renal cell carcinoma.
IGF-1 protects against angiotensin II-induced cardiac fibrosis by targeting αSMA
Authors: Ock Sangmi , Ham Woojin , Kang Chae Won , Kang Hyun , Lee Wang Soo , Kim Jaetaek 
Published: July 2021

AbstractThe insulin-like growth factor 1 receptor (IGF-1R) signaling in cardiomyocytes is implicated in physiological hypertrophy and myocardial aging. Although fibroblasts account for a small amount of the heart, they are activated when the heart is damaged to promote cardiac remodeling. However, the role of IGF-1R signaling in cardiac fibroblasts is still unknown. In this study, we investigated the roles of IGF-1 signaling during agonist-induced cardiac fibrosis and evaluated the molecular mechanisms in cultured cardiac fibroblasts. Using an experimental model of cardiac fibrosis with angiotensin II/phenylephrine (AngII/PE) infusion, we found severe interstitial fibrosis in the AngII/PE infused myofibroblast-specific IGF-1R knockout mice compared to the wild-type mice. In contrast, low-dose IGF-1 infusion markedly attenuated AngII-induced cardiac fibrosis by inhibiting fibroblast proliferation and differentiation. Mechanistically, we demonstrated that IGF-1-attenuated AngII-induced cardiac fibrosis through the Akt pathway and through suppression of rho-associated coiled-coil containing kinases (ROCK)2-mediated α-smooth muscle actin (αSMA) expression. Our study highlights a novel function of the IGF-1/IGF-1R signaling in agonist-induced cardiac fibrosis. We propose that low-dose IGF-1 may be an efficacious therapeutic avenue against cardiac fibrosis.