Nanomaterials are the new additives for drilling fluids that can improve its properties and eliminate problems due to increased downtime and well costs. The objective of this research is to select the optimum concentration of nanoparticles that enhance drilling fluid properties and hydraulics. This study investigates the effects of commercially available nanoparticles on the rheological and filtration properties and optimizes the hydraulics of water-based drilling fluids. In this study, the samples were prepared as water-based muds with and without various concentrations of 5.7 nm colloidal silica dioxide nanoparticles. Series of laboratory experiments were carried out for all samples using standard API Low Pressure Low Temperature (LPLT) filtration and rheological tests. Two mud systems at different pH conditions were used to evaluate the impact of nanoparticles. A commercial software was used to evaluate the impact of the nanoparticles on the Equivalent Circulation Density (ECD) and the circulation pressure loss in a deviated wellbore. Results show enhancements in the rheological and filtration properties for water-based muds treated by the nanoparticles used in this study with concentrations below 0.7% by weight. Furthermore, the results show the ability of these nanoparticles to make the filter cake consistent, compacted, and thin. The results reflect the negative impact of the nanoparticles with concentrations above 0.7% by weight on some of the rheological properties. The optimum nanomaterial concentrations with the best properties were observed as (0.1%-0.3%) by weight. Furthermore, the concentration of 0.1% by weight reflected the significant reduction in the ECD and the circulating pressure loss. Nanoparticles used in this research can play a vital role in reducing drilling problems. Multilateral wells, slim holes and deep horizontal wells can be drilled by using water-based mud with the addition of proper nanoparticles and eliminating the need for oil-based muds that are expensive and environmentally unacceptable. However, it is critical to select the proper size and concentration of nanoparticles in order to eliminate its negative impact on the drilling fluid properties.

As sensitive and electro-chemically active additives, anionic nanoparticles can be used to develop various water-based mud designs to fulfill different drilling conditions with less costs. For an optimum performance, however, they must be carefully selected and formulated. The objective of this study was to compare and evaluate various properties of water-based nanomuds. This was achieved by investigating the impact of very low concentrations of commercially affordable three types of negatively charged nanoparticles on the rheological, hydraulic and filtration properties of a high pH "flocculated" water-based mud. Simultaneously, the superior and insufficient types and concentrations were explored. In this research, four concentrations of each of anionic nanosilica, nanotitanium, and nanoaluminum were used to treat the high pH (11.5-12) water-based mud. Sequences of API experimental tests were conducted by using standard Low Pressure Low Temperature (LPLT) filtration and rheological devices for all samples. For the hydraulic evaluation, a commercially available software was used to simulate the impact of the nanoparticles on the equivalent circulation density (ECD) and the drillpipe circulation pressure in a typical directional well. The results show significant improvements in the rheological and hydraulics properties of the flocculated water-based muds treated by 0.1% wt. or less of nanosilica and 0.3% wt. or less of nanotitanium and nanoaluminum. For the higher concentrations, no more improvements were obtained. Further, the results show the ability of nanosilica and nanotitanium to reduce the filtration volume and no filtration reduction based on nanoaluminum. However, all the nanoparticles enhance the mudcake structure, but differently, and prevent the spurt water loss completely. The current nanoparticle types can be used to develop a qualified mud design, thereby reducing drilling problems, such as stuck pipe, formation damage, wellbore instability, downhole equipment failure, mud circulation loss, and shale swelling if they are properly formulated. Thus, the more complicated wells can be drilled by using water-based nano muds and by eliminating the high costs and bad environmental impacts of using oil-based muds.

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Studies on Kawasaki disease (KD) in Arab countries are scarce, often providing incomplete data. This along with the benefits of multicenter research collaboratives led to the creation of the KD Arab Initiative [Kawarabi] consortium. An anonymous survey was completed among potential collaborative Arab medical institutions to assess burden of KD in those countries and resources available to physicians. An online 32-item survey was distributed to participating institutions after conducting face validity. One survey per institution was collected. Nineteen physicians from 12 countries completed the survey representing 19 out of 20 institutions (response rate of 95%). Fifteen (79%) institutions referred to the 2017 American Heart Association guidelines when managing a patient with KD. Intravenous immunoglobulin (IVIG) is not readily available at 2 institutions (11%) yet available in the country. In one center (5%), IVIG is imported on-demand. The knowledge and awareness among countries’ general population was graded (0 to 10) at median/interquartiles (IQR) 3 (2–5) and at median/IQR 7 (6–8) in the medical community outside their institution. Practice variations in KD management and treatment across Arab countries require solid proactive collaboration. The low awareness and knowledge estimates about KD among the general population contrasted with a high level among the medical community. The Kawarabi collaborative will offer a platform to assess disease burden of KD, among Arab population, decrease practice variation and foster population-based knowledge. Supplementary Information The online version contains supplementary material available at 10.1007/s00246-022-02844-w.

Congenital heart diseases (CHD) are common causes of cardiovascular morbidity and mortality among young children and adolescents. It is the most common form of structural congenital defects. Little is known about incidence and type of these disorders in Sulaimani. Therefore, this study was undertaken to determine the incidence of congenital heart diseases and their types in Sulaimani Governorate. The study was conducted in Sulaimani Pediatric Teaching Hospital and the Maternity Hospital during January 2015 to December 2016. A sample of 400 consecutive cases of CHD in children aged 0-12 years was recruited attending the echocardiographic department of the hospital for diagnosis or follow-up purposes. Demographic data was collected through a face-to-face interview with the mothers of cases. A total number of new live births for 2015-2016 and those with congenital heart diseases were obtained from the medical records of the department of statistics of Sulaimani Maternity Teaching Hospital. The overall incidence of all types of congenital heart diseases was 1.7/1000, 1.6/1000 live births for the year 2015 and 2016 respectively. There was a statistically significant difference in incidence between males and females over the two years, male to female risk ratio 1.83 (95% CI 1.09-3.14, p 0.007). The commonest types of cyanotic congenital heart diseases were tetralogy of Fallot (38.9% of all cyanotic defects), complete atrioventricular canal (22.1%), and transposition of great arteries (18.2%), while the most common types of non-cyanotic congenital heart disease were atrial septal defect (34.1% of all non-cyanotic defects), ventricular septal defect (31.6%), and the other defects are less common. In conclusion, tetralogy of Fallot, atrial septal defects, and ventricular septal defects are the commonest congenital heart deformities in Sulaimani Governorate; the incidence is lower than other countries but this could be an underestimation.