Pore- to field-scale modelling of three-phase flow processes in heterogeneous reservoirs with arbitrary wettability

Most reservoirs, such as carbonate reservoirs not only have structural heterogeneities (e.g. complexly shaped geobodies or fractures). But they also have distributed wettabilities and are mixed- to oil-wet. The interplay of structural and wettability heterogeneities impacts sweep efficiency and oil recovery. Choosing the appropriate Improved Oil Recovery (IOR) or Enhanced Oil Recovery (EOR) technique based on adequate predictions of oil recovery requires a sound understanding of the fundamental controls on fluid flow in mixed- to oil-wet andstructurally complex rocks. The underlying multiphase flow processes are modelled with physically robust flow functions, i.e. relative permeability and capillary pressure functions. Obtaining these flow functions is a challenging task, especially when three fluid phases coexist, such as during Water-Alternating-Gas (WAG) injection. In this work we use pore-network modelling, a reliable and physically based simulation tool, to predict three-phase flow functions. We have developed a new three-phase flow pore-network model for rocks with arbitrary wettability, which allows us to analyse the fundamental multi-phase displacement processes. Unlike other models, our model combines three main features: (I) A novel thermodynamic criterion for formation and collapse of oil layers that strongly depends on the fluid spreading behaviour and the rock wettability. The model hence captures film/layer flow of oil accurately, which impacts, in particular, the oil relative permeability at low oil saturation and hence the accurate prediction of residual oil. (II) Multiple displacement chains, where injection of one phase at the inlet triggers a chain of interface displacements throughout the network. This allows accurate modelling of the mobilization of disconnected phase clusters that arise during higher order (WAG) floods. (III) The model takes as input realistic 3D pore-networks extracted from pore-space reconstruction methods and Computed Tomography (CT) images, preserving both topology and pore shape of the rock. The model comprises a constrained set of parameters that can be tuned to mimic the wetting state of a given reservoir. We have validated our model against available experimental data for a range of wettabilities. We demonstrate the importance of film and layer flow for the continuity of the various phases during subsequent WAG cycles and for the residual oil saturations. A sensitivity analysis has been carried out with the full 3D model to predict three-phase relative permeabilities and residual oil saturations for WAG cycles under various wetting conditions with different flood end-points and for different rock types. This revealed a wide range of three-phase relative permeabilities and residual saturations. The pore-scale generated three-phase flow functions have then been used in a heterogeneous reservoir model. Here we demonstrate their impact on the sweep efficiency after gas injection and WAG for a range of realistic wettability scenarios. We show that the uncertainty in flow functions can be as big as the geological uncertainty in a reservoir model that was history matched for an extended waterflood

Outcomes of the National Head and Neck Cancer Awareness and Screening Campaign in Oman

Objectives: The prognosis of head and neck cancer (HNC) depends substantially on disease stage at the time of diagnosis. Unfortunately, the majority of HNC patients present at relatively late stages. In Oman, a national screening campaign was conducted to increase public awareness of HNC and encourage early detection. This study aimed to report the outcomes of that campaign. Methods: The campaign took the form of biannual events conducted at a tertiary care centre and in public malls in Muscat, Oman from April 2015 to July 2019. Data were collected from participants using the Head and Neck Cancer Alliance screening form. Otolaryngologists and oral maxillofacial surgeons performed a thorough physical evaluation of the head and neck region. Results: Of the 1,500 individuals visiting the hospital and malls during the campaign events, a total of 509 agreed to undergo screening (response rate: 33.9%). Of these, 12.8% had positive screening results and 5.9% required further evaluation. However, none of the cases with suspicious findings were found to be malignant after a thorough evaluation. Overall, 16.9% of the participants were aware of the early signs of HNC; in addition, 5.5% knew how to perform an oral self-examination. Conclusion: Screening is a simple and safe method for the prevention and early detection of HNC. Mass screening and public awareness programmes may help to reduce the burden of this disease in Oman.Keywords: Head and Neck Cancer; Early Detection of Cancer; Mass Screening; Knowledge; Health Risk Behaviors; Oman

Source-use Practice in Research Reports: The Case of Colleges of Applied Sciences Undergraduates in the Disciplines of Accounting and International Business

Source-use practice is important to the construction of scientific knowledge. This study attempts to develop understanding of the use of sources in undergraduate research report writing. It is situated in one college of the Colleges of Applied Sciences (CAS) in Oman, and examines the different rhetorical functions of citations used by final-year Accounting and International Business students, as well as the contextual layers that seem to have shaped students’ source-use practices. Data were collected from 11 students from each discipline and their 6 teachers, and 22 research reports were analysed to identify the rhetorical function of all citations appearing in all sections of students’ research reports. Petrić’s (2007) typology, which consists of 9 functions of citations, was used to analyse the data. Results of the textual analysis show that most citations were located in the literature review chapters, and citations were mainly used to display knowledge and summarize sources. There were a few attempts to use sources for more complex rhetorical functions in both disciplines; these attempts were only made by students with a higher level of English proficiency. Findings also suggest two new functions that are not included in Petrić’s typology: textual structuring and acknowledgment of authorship for content display. These functions further indicate students’ extreme lack of understanding of the role of sources in academic writing and their inability to synthesize. In addition, relevant documents were examined and interviews with the students and their teachers were conducted. Analysis of these data suggest that the college, department, task, teacher, and prior student cohorts all play a role in influencing students’ source-use knowledge and practices. Pedagogical implications are suggested to inform EAP instruction regarding the teaching of source use and to guide constructive collaboration between EAP teachers and subject-area teachers in CAS to support the teaching of citation use

Undergraduate Students’ Attitudes towards Online Language Classes during the COVID-19 Pandemic: Are Students Thriving or Surviving?

The global pandemic has tremendously affected all walks of life. Education is no exception, with online learning being the only available mode of learning. This sudden shift to online learning, which was given marginal attention before the pandemic, has entailed many challenges for decision-makers, teachers and students alike. This paper highlights the general attitudes of Omani undergraduate students towards online language courses amid the COVID-19 pandemic. The participants are 155 undergraduate students who took online English requirements in the Centre for Preparatory Studies (CPS) at Sultan Qaboos University (SQU) in Spring 2021. A quantitative approach to data collection has been embraced to collect students’ perspectives on different aspects related to their online learning experience. A survey addressing different aspects of online learning related to connectivity, communication, learning experience and learning environment, assessment and learner’s online identity was conducted. The findings show that students are thriving and have a general positive attitude towards the online learning experience. However, students reported some factors which made the online instruction stressful such as technical issues, marathon assignments, disconnectedness and online identity. The findings of the study can be good indicators that should be taken into consideration when designing, running and evaluating online language courses for undergraduate students to help them thrive during this mode of learning

Incidence of pediatric glomerular diseases in Arab world: A systematic review

Despite the high number of Arab children, there are a scanty available data about different types of pediatric glomerular diseases in all Arab countries. Very few Arab countries have a national renal biopsy registry. In this review, we performed a systematic review analyzing the incidence of pediatric glomerular disease in all Arab countries. Relevant manuscripts in all 22 Arab countries found through searches of Medline, Science Direct, Embase and Google Scholar were evaluated. The period was from January 1990 to March 2018. A total of 17 manuscripts containing 3083 renal biopsies from seven countries were analyzed. Male-to-female ratio was 1.3:1. Saudi Arabia revealed the most published studies with seven papers. The average period of the study was 8.63 years. Retrospective studies represent 94.12%. Minimal change disease (MCD) (29.25%), focal and segmental glomerulosclerosis (FSGS) (22.34%), mesangioproliferative glomerulonephritis (14.78%), membranoproliferative glomerulonephritis (6.9%), IgA nephropathy (3.98%), and membranous glomerulopathy (2.65%) were the top types of primary glomerular diseases. The most common types of secondary glomerular diseases were lupus nephritis (36.1%), postinfectious glomerulonephritis (17.62%), congenital nephrotic syndrome (6.08%), Alport syndrome (4.71%), Henoch–Schönlein purpura (1.49%), and amyloidosis (1.36%). In conclusion, MCD and lupus nephritis are, respectively, the most common types of primary and secondary glomerular diseases in children of all evaluated Arab countries. FSGS is the predominant pattern of primary glomerular diseases in Asian Arab countries. The trend of all types of glomerular diseases has not changed in the past 28 years except a noted significant reduction in FSGS. Arab countries are strongly recommended to establish a renal biopsy registry

A Rare Case of Emphysematous Endocarditis Caused by Escherichia coli

Infective endocarditis (IE) is an infection of the heart endocardium with significant morbidity and mortality. Gram negative infection, particularly emphysematous IE, is an extremely rare and life-threatening disease. We report a 59-year-old diabetic female patient who was admitted to a secondary care hospital in Rustaq, Oman, in 2017 with the diagnosis of pneumonia for which she was started on antibiotics. Shortly afterwards, she developed facial and mouth deviation and became more tachypneic. Computed tomography of the brain demonstrated bilateral multiple small infarcts. Pulmonary angiography computed tomography was performed which ruled out pulmonary embolism. Nonetheless, it revealed an air-containing lesion around the mitral valve. Transthoracic echocardiography demonstrated a hyperechoic mobile lesion related to the mitral valve. Blood culture grew Escherichia coli and the diagnosis of E. coli emphysematous IE was made based on modified Duke criteria. The patient’s clinical condition deteriorated and she suffered cardiac arrest leading to her death. The recommended treatment for non-HACEK IE includes an extended antibiotic course and surgery for selected patients. Keywords: Endocarditis; Escherichia coli; Mitral Valve; Echocardiography; Intracranial Embolism; Emphysema; Case Report; Oman.

A review of the prevalence of COVID-19 in the Arab world

INTRODUCTION: Coronavirus disease 2019 (COVID-19) is a rapidly spreading disease worldwide. It is a real test for all health authorities including Arab countries. In this review, we aimed to assess the prevalence of COVID-19 in the Arab world. In addition, to compare the findings of this study with other top affected countries. METHODOLOGY: We searched for official websites from the Ministries of Health and other official sources in all 22 Arab countries. Medline, Science Direct and Google Scholar websites were also used to search for COVID-19, 2019 novel coronavirus, SARS-CoV-2 and coronavirus. The time period was from 1 January 2020 to 31 May 2020. RESULTS: As of May 31, 2020, COVID-19 has caused 290,428 confirmed cases, 3,696 deaths and 157,886 cured cases in all Arab countries. In terms of confirmed cases, Saudi Arabia followed by Qatar, UAE, Kuwait and Egypt have the highest reported cases. However, the total number of deaths was dominant in Egypt, followed by Algeria, Saudi Arabia, Sudan and UAE. In comparison to other non-Arab countries and confirmed cases, Arab countries come fourth after USA, Brazil and Russia. In terms of death, the Arab world is not listed as the top ten affected countries as only scored eight deaths per million have been recorded. CONCLUSIONS: Most Arab countries took some serious early steps to minimize the outbreak of COVID-19. At the moment, controlling the source of infection, the route of transmission and taking care of infected patients are the main challenges for health authorities in all Arab countries

Platinum-Based Drugs Differentially Affect the Ultrastructure of Breast Cancer Cell Types

Breast cancer (BC) is the most common cause of cancer-related death worldwide. Although platinum-based drugs (PBDs) are effective anticancer agents, responsive patients eventually become resistant. While resistance of some cancers to PBDs has been explored, the cellular responses of BC cells are not studied yet. Therefore, we aim to assess the differential effects of PBDs on BC ultrastructure. Three representative cells were treated with different concentrations and timing of Cisplatin, Carboplatin, and Oxaliplatin. Changes on cell surface and ultrastructure were detected by scanning (SEM) and transmission electron microscope (TEM). In SEM, control cells were semiflattened containing microvilli with extending lamellipodia while treated ones were round with irregular surface and several pores, indicating drug entry. Prolonged treatment resembled distinct apoptotic features such as shrinkage, membrane blebs, and narrowing of lamellipodia with blunt microvilli. TEM detected PBDs’ deposits that scattered among cellular organelles inducing structural distortion, lumen swelling, chromatin condensation, and nuclear fragmentation. Deposits were attracted to fat droplets, explained by drug hydrophobic properties, while later they were located close to cell membrane, suggesting drug efflux. Phagosomes with destructed organelles and deposits were detected as defending mechanism. Understanding BC cells response to PBDs might provide new insight for an effective treatment