Introduction: Elevated neutrophil-lymphocyte ratio (NLR) has been associated with poorer outcomes in children undergoing congenital heart surgery under cardiopulmonary bypass (CPB). Objective: To compare preoperative NLR levels between cyanotic and acyanotic children undergoing surgical repair with CPB. Methods: We performed a retrospective cohort study in 60-paired children (30 with tetralogy of Fallot [TOF] and 30 with ventricular septal defect [VSD]) between January 2018 and December 2019 matched by age, weight, and gender. Preoperative NLR was measured from the last complete blood count test before the surgery. All of them had negative viral screening. Results: The median age in VSD children was 9.5 months (interquartile range [IQR]:

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The abrasive Pre-Khuff sandstones combined with high downhole temperatures and the propensity for BHA and bit sticking present a uniquely hostile drilling environment. These limit run durations and the ability to optimize ROP with the use of conventional rotary assemblies, PDMs/conventional turbodrills and/or rotary steerable systems. Catastrophic damage or loss of drill strings, poor hole quality and logging problems are common even with the advancements in PDC bit technologies. Of the systems listed above, historically, turbodrilling systems have best addressed the high temperatures and the abrasive nature of the Pre-Khuff formations and held the potential for drilling economics optimization but have been unsuccessful in addressing bit sticking challenges. The resultant development of best practices produced only marginal results because they require surface intervention and thus did not fully address sticking problems (in particular bit sticking). The engineering challenge was to develop a downhole device that automatically engages and imparts sufficient drill string torque to maintain bit rotation. The turbodrill device disengages when conditions return to normal and returns the operation to high productivity drilling without surface intervention. The turbodrill device coupled with advancements in BHA design, stabilizer and jar placement along with formation characterization and drill bit technology, is the solution to bit sticking incidents. Presented with this advancement in turbodrilling technology, the Operator/Service Company team has completed trials using this technology and presents data that supports the use and benefits of anti-sticking technologies. With this success, the team has regained focus on drilling optimization and reset the goal for single run-casing point to casing point. Introduction Saudi Aramco continually seeks ways to improve drilling efficiencies through the difficult Pre-Khuff Formations. This paper is about a fortuitous trial of last resort that has delivered favorable results. In Saudi Arabia, Pre-Khuff Formations (Unayzah, Jauf; Tawil, Sharawra, Qusaiba, Sarah, Qasim; and Saq) are encountered at depths between 13,000 and 17,000 feet. These strata primarily comprise sandstones interbedded with shales, limestone, dolomite, anhydrite and siltstones. Sandstones with some siltstone predominate in the top Unayzah strata downward through the Qusaiba. At the bottom, the Sarah can also include some interbedded shale. The Unayzah and Jauf are generally characterized by hard, abrasive sandstones interbedded with shale and siltstone. Unconfined compressive strengths can reach 40,000 psi with internal angles of friction ranging from 25° to 75°. Hardness, abrasiveness, toughness, irregularity in size and orientation of rock constituents, and problems with sticking all contribute to a significant challenge and expense associated with drilling in the Pre-Khuff Formations. High wear rates on bits and BHA components cause a significant potential for premature equipment failures, limit on bottom rotating time, and necessitate long and frequent trips. The Upper Pre-Khuff (Unayzah to Jauf) strata are the most difficult of the Pre-Khuff formations to drill. These strata typically consist of very irregular, fine to coarse grained pebbles and conglomerates that can vary significantly in their dimensions and hardnesses (both in adjacent wells and at different depths in a particular well) and the Jauf formation may also contain Pyrite.

Hurricane Andrew made landfall in Homestead, Florida as a category 5 hurricane on August 24, 1992. This 30-year anniversary review examines the changes within the Florida and coastal United States homeowners insurance markets. We review market changes specifically related to market concentration, risk pricing, and volatility. We find that most states have become less concentrated since the early 1990s. We also find that risk pricing has changed since Hurricane Andrew with the creation of a new catastrophe market where insurers rely on catastrophe models to help price catastrophe-prone risks. Finally, we see that most states did not experience much volatility over the 30 years following Hurricane Andrew, with Florida being an exception. This is most likely due to the large population growth, increase in fraudulent claims, and high litigation costs. Overall, Hurricane Andrew changed how the insurance industry viewed catastrophic events and thus changed how they manage, model, and price catastrophe-prone areas.

Here we present our initial results for fabrication of 3D cellular architectures of tungsten carbide by 3D printing. We 3D printed cellular architectures of a biopolymer gel composite that consisted of iotacarrageenan and chitin as carbon precursors and tungsten tri-oxide as the tungsten source. The 3D printed gel composite was dried to obtain a 3D structure of biopolymer xerogel. Heat treatment of the xerogel structures resulted in 3D cellular architectures of porous tungsten carbide (WC). Significant shrinkage occurred during the drying and heat treatment process. The X-ray diffraction pattern confirmed that WC was formed after heat treatment. Scanning electron microscopy showed that the WC formed here featured a porous network of particle agglomerates. Ongoing work includes compressive testing to determine the Young's modulus of samples. A design of experiments will be implemented to develop a relationship between mechanical behavior and the geometry of the cellular architecture. Additionally, shrinkage, material solvent, printing substrate and filament diameter require further study to control rheology and increase precision during fabrication.