Challenges during Operation and Shutdown of Waxy Crude Pipelines

Transportation of waxy crude oil faces great challenges due to shear and temperature dependency. At high temperatures, waxy crude exhibits low viscous Newtonian behavior where the resistance to flow due to friction is low, and hence low pumping pressure is required to transport it. At low temperatures, however, the crude exhibits shear thinning non-Newtonian behavior where its apparent viscosity becomes shear-dependent. In such cases, the operated pipeline needs to maintain a high pressure to guarantee a continuous flow. Moreover, due to heat transfer between the internal pipeline and surroundings, oil temperature declines along the pipeline. It follows that the crude viscosity and, hence, frictional resistance increase. If the flow is interrupted for any reason, i.e., emergency or planned shutdown, then the restartability of the pipeline becomes a challenge because of the nonexistence of heating generated from friction. In this chapter, the challenges normally facing transportation of waxy crude oil will be discussed. The chapter will introduce the rheological properties of waxy crude oil and explain and describe how these properties can affect the pressure losses inside the pipeline during its operation and shutdown. The measures that need to be considered when designing a waxy crude pipeline will be discussed

Loss-of-function mutations in UDP-Glucose 6-Dehydrogenase cause recessive developmental epileptic encephalopathy

Developmental epileptic encephalopathies are devastating disorders characterized by intractable epileptic seizures and developmental delay. Here, we report an allelic series of germline recessive mutations in UGDH in 36 cases from 25 families presenting with epileptic encephalopathy with developmental delay and hypotonia. UGDH encodes an oxidoreductase that converts UDP-glucose to UDP-glucuronic acid, a key component of specific proteoglycans and glycolipids. Consistent with being loss-of-function alleles, we show using patients’ primary fibroblasts and biochemical assays, that these mutations either impair UGDH stability, oligomerization, or enzymatic activity. In vitro, patient-derived cerebral organoids are smaller with a reduced number of proliferating neuronal progenitors while mutant ugdh zebrafish do not phenocopy the human disease. Our study defines UGDH as a key player for the production of extracellular matrix components that are essential for human brain development. Based on the incidence of variants observed, UGDH mutations are likely to be a frequent cause of recessive epileptic encephalopathy

Polymers additive for improving the flow properties of lubricating oil

An investigation was conducted for the improvement of the physical properties of Lubricating oil. The copolymer used is ethylene propylene diene monomer (EPDM). The oil viscosity index (VI) and viscosity/temperature characteristics were improved at different concentrations 2468 and 10% by weight solutions. The efficiency of the additive as viscosity index and flow improvers was investigated. FT-IR analysis determines the change in the carbonyl group. Thermo gravimetric analysis (TGA), is used to study the degradation and thermal stability of the studied base stock samples. Keywords: Lubricating oil, Copolymer (EPDM) viscosity index, FT-IR spectroscopy, Thermogravimetric analysi

Quantiferon vs. tuberculin testing in detection of latent tuberculous infection among chronic renal failure patients

Latent tuberculous infection (LTBI) lacks a solid gold standard in its diagnosis and many clinicians rely upon tuberculin testing, however there has been an increasing interest in depending on Interferon Gamma Release Assays especially Quantiferon-Gold (QFT-G). Since chronic renal failure (CRF) poses an important health problem in Egypt and taking into consideration the immuno compromisation caused by this condition, LTBI detection emerged as an important health concern in those patients. In this study, the aim was to find which tool was better in the detection of LTBI in CRF patients. Forty patients with chronic renal failure and on hemodialysis, with exclusion of active tuberculosis and other immuno compromisation conditions were tested for LTBI by tuberculin skin test (TST) and QFT-G. 25% of the tested showed LTBI. It was found that although both tests gave comparable results, yet there was a discrepancy between both. TST+/QFT+ group was 10%, TST+/QFT− group was 5%, TST−/QFT+ was 10% and TST−/QFT− group was 75%. Conclusion: In Chronic renal failure and probably any immuno compromisation setting, it would be better to perform both tuberculin and Quantiferon tests to detect latent tuberculous infection

Comprehensive review of progress made in soil electrokinetic research during 1993–2020, part II. No.1: Materials additives for enhancing the intensification process during 2017–2020

This review is a follow-up to our previous review titled “comprehensive review of progress made in soil electrokinetic research during 1993–2020, Part I: process design modifications with brief summaries of main output”. In this review, we have summarized the material additives that are utilized for the enhancement of soil electrokinetic remediation (SEKR) efficiency within the last four years (2017–2020). This review has been divided into six subjects according to determined SEKR categories including removal of inorganic contaminants, removal of organic contaminants, SEKR enhancement using permeable reactive barrier (PRB), SEKR for solidification and soil improvement, SEKR enhancement using an oxidation process, and SEKR enhancement using bioremediation and phytoremediation. Various enhancement materials have been added to improve the primary endeavors of SEKR and the summaries of the output were included in this review. In the SEKR experiments in which inorganic and organic contaminants were removed, the process was evaluated based on the process driving mechanism, particularly electromigration and electro-osmosis. Once the performance of SEKR was inefficient, the SEKR processing was integrated with PRB, oxidation, and bioremediation for significant improvements in SEKR performance. Therefore, the primary aim of our review is to provide a comparison of material additives for the SEKR removal intensification process from 2017 to 2020 to provide a review of the past materials that improved the SEKR performances and to simplify future innovation. During 2017–2020, SEKR studies focused on inorganic and organic contaminants remediation, whereas, few SEKR studies have focused on solidification and soil improvement. The SEKR has been utilized for dewatering, but in this case, the materials added were limited. The insufficient of relevant information on this subject was our primary motivation to write this review

Mutations in the NHEJ component XRCC4 cause primordial dwarfism

Non-homologous end joining (NHEJ) is a key cellular process ensuring genome integrity. Mutations in several components of the NHEJ pathway have been identified, often associated with severe combined immunodeficiency (SCID), consistent with the requirement for NHEJ during V(D)J recombination to ensure diversity of the adaptive immune system. In contrast, we have recently found that biallelic mutations in LIG4 are a common cause of microcephalic primordial dwarfism (MPD), a phenotype characterized by prenatal-onset extreme global growth failure. Here we provide definitive molecular genetic evidence supported by biochemical, cellular, and immunological data for mutations in XRCC4, encoding the obligate binding partner of LIG4, causing MPD. We report the identification of biallelic mutations in XRCC4 in five families. Biochemical and cellular studies demonstrate that these alterations substantially decrease XRCC4 protein levels leading to reduced cellular ligase IV activity. Consequently, NHEJ-dependent repair of ionizing-radiation-induced DNA double-strand breaks is compromised in XRCC4 cells. Similarly, immunoglobulin junctional diversification is impaired in cells. However, immunoglobulin levels are normal, and individuals lack overt signs of immunodeficiency. Additionally, in contrast to individuals with LIG4 mutations, pancytopenia leading to bone marrow failure has not bee