Placental Tumour : What could it be?

Placental tumours include placental chorioangiomas, teratomas, haemangiomas, and haematomas. Placental chorioangiomas are benign vascular tumours and are the most common placental tumours, with a prevalence of 1%. Large placental chorioangiomas are rare and may lead to pregnancy complications and poor perinatal outcomes. These complications include fetal anaemia, hydrops fetalis, fetal growth restriction, polyhydramnios, and preterm delivery. We report a case of a large placental chorioangioma, the antenatal management and the maternal and fetal outcomes

Evaluation of Compositional Effects on Gas-Oil Miscibility and Gas-Assisted Gravity Drainage (GAGD) EOR Process

The Vanishing interface technique (VIT), offers fast and accurate determination of minimum miscibility pressure (MMP) between the reservoir crude oil and the various gases injected for enhancing oil recovery (EOR). The technique is based on miscibility being the condition where an interface between the injected fluid and the reservoir crude oil vanishes. This research has evaluated the effect of the gas-oil ratio on zero-IFT pressure. VIT experiments were simulated using an equation of state (EOS) and the Parachor model. This work proves the robustness of VIT in estimating miscibility pressures for gas injection EOR projects. Also this work presents a simple method for estimating near-miscibility pressures (NMP) that are based on a gas-oil interfacial tension (IFT) calculation procedure. The method evaluates near miscibility conditions at low (as against zero) IFT and relies only on using EOS and the Parachor model. The results show that NMP estimation method is reasonably accurate, MMPs agreed with slim tube MMPs within 7%. In recent years CO2-based EOR projects have been steadily gaining ground over all other EOR processes. However, due to limited supply of pure CO2 availability, an alternative option is to utilize emitted flue gas. Miscibility pressures were successfully determined using VIT of different gas mixtures with n-decane (nC10), namely CO2, N2, CO2- N2 (85%-15%) and CO2- N2 (15%- 85%). This proves the ease of applicability of VIT to evaluate the effect of injected gas type and composition on gas-oil miscibility. Earlier reported Gas-Assisted Gravity Drainage (GAGD) work using CO2 for gas injection resulted in good oil recoveries. To expand the applicability of using GAGD in areas where there is limited CO2, an experimental study was conducted to examine the effect of using different gases on GAGD performance. CO2, N2 and flue gas were used with nC10 as the oil phase, in conducting high-pressure corefloods. The floods resulted in oil recoveries in the range of 30-49 % (immiscible mode) of remaining oil after water floods. This work has demonstrated the superiority of GAGD over the other gas injection methods currently practiced, such as WAG and CGI, using CO2 or any other gas

Re: Health Professions Education in Oman : A contemporary perspective

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The Construction of a Monoclonal Diagnostic System for the Field Detection of V. cholerae

Cholera is an acute diarrheal disease that is characterized by massive loss of fluids and electrolytes. If it remains untreated, in its most severe form it may result in death. The causative agent is Vibrio cholerae, which was first described by Robert Koch (1884). The disease is contracted by the ingestion of water or food contaminated by the excreta of persons harbouring the bacilli. Since it is exquisitely sensitive to gastric acid, at least 100 million vibrios are required for infection in a reasonably healthy person, but in a malnourished victim or someone with no gastric acidity, 10,000 to 1 million vibrios can produce disease. The human is the only host of V. cholerae (Smith, 1985)

Introducing Critical Pedagogy to English Language Teachers at Tertiary Education in Oman: Attitudes, Potentialities and Challenges

Based on critical theory and postmodernist paradigms, the aim of this study is to introduce Critical Pedagogy (CP) to English language teachers in four higher education institutions in Oman via an action research methodology. Eventually, the ultimate purpose of this study is to create a change by raising teachers' awareness of CP. Although CP cannot be reduced to a monolithic body of discourse, through a review of literature, unified principles have been put forward by various critical educators that shape this study: (1) the political nature of education, (2) the nature of knowledge, (3) education for empowerment, (4) education for transformation, (5) integrating the world into the classroom, and (6) the meaning of ‘critical’ within CP framework. Five data collection tools are utilized during the four phases of the study. In the first phase, 178 teachers complete a five-point Likert scale questionnaire. In the second phase, an article is sent to teachers and a workshop on CP is conducted for 160 English language teachers in the four colleges. Then, documents (102 workshop evaluation forms and 25 lesson plans) and semi-structured interviews with 20 teachers are analysed to elicit teachers' attitudes towards CP and its potentialities and challenges in teaching English. Lastly, in the fourth phase, eight classroom observations are conducted to obtain a deeper insight of the feasibilities and challenges of implementing CP. The findings show teachers’ initial lack of awareness of CP as a possible approach to teaching English. After the intervention, the findings reveal that teachers have various attitudes towards applying CP, ranging from caution to full support. Some teachers resist some of CP’s premises while others are in-between. Although the findings of the study indicate the great potential of CP, the participants acknowledge the existence of many challenges to its implementation; these challenges are related to students, teachers and the college system. These findings are discussed in light of the existing literature and the Omani context. Implications for teachers, pre-service and in-service teacher education programmes and policy makers are drawn based on the study's findings

Potential Predictors of Sudden Cardiac Death in Aortic Valve Disease

Although sudden death continues to claim 15 to 20% of patients with aortic valve disease, the exact cause still remains speculative. It has been the assumption of many workers that these deaths result from ventricular tachyarrhythmias. The major aim of this thesis was therefore to assess the prevalence of ventricular arrhythmias in patients with aortic valve disease and to evaluate their significance by signal-averaged electrocardiography (SAECG). A total of 100 patients, 55 with predominant aortic stenosis (AS) with a mean transaortic gradient of 81+/-27 mmHg, 16 with predominant aortic regurgitation (AR) and 29 with combined AS and AR were studied prior to aortic valve replacement (AVR). Substantial left ventricular hypertrophy was present with a mean echocardiographic left ventricular mass index of 210+/-72 g/m2. Left ventricular systolic and diastolic function were normal in 94% and 61% of patients respectively. Coronary angiography was performed in 89 patients of whom 50 (56%) had chest pain typical of angina pectoris and 21 (24%) had significant coronary artery disease. Angina was present in 20 of these 21 patients (95%). Thus angina could predict the presence of significant coronary artery disease with 95% sensitivity and 54% specificity. In agreement with previous work, this study has shown a high prevalence of complex ventricular arrhythmias. Nonsustained ventricular tachycardia (NSVT) was detected by ambulatory electrocardiographic monitoring in 9 (9%) patients of whom only one had late potentials on SAECG. The frequency of ventricular arrhythmias was not related to the degree of left ventricular hypertrophy or the severity of aortic valve disease. Left ventricular function did not have any effect on ventricular arrhythmias. A high prevalence of complex ventricular arrhythmias was also seen in the early (5 to 7 days post AVR) and late (121+/-24 days post AVR) post-operative periods. The frequency of ventricular arrhythmias was not affected by AVR. In the late post-operative period, 4 patients had NSVT, but none of them had late potentials on SAECG. As with the pre-operative results, there was little to suggest the presence of an arrhythmogenic substrate in these patients in view of the absence of late potentials on SAECG. Furthermore, no sustained ventricular arrhythmias were detected in the 3 study periods. Aortic valve replacement was accompanied by a significant regression in echocardiographic left ventricular hypertrophy in patients with predominant AS and those with combined AS and AR. Of the total 100 patients in this study, 75 were on the cardiac surgical waiting list of whom 60 have already undergone operation. There have been 7 deaths (7%) during the study period, 3 of them occurring suddenly in patients awaiting surgery. Thus, the incidence of sudden death while awaiting operation was 4%. It has been suggested that patients with decreased heart-rate variability have decreased vagal tone, increased sympathetic activity or both and hence are at a higher risk of developing ventricular fibrillation and sudden death. Cardiovascular autonomic function was assessed in 47 patients prior to AVR and repeated in 10 patients 3 months following AVR. Abnormal heart-rate variation during deep breathing was detected in 18 (38%) patients. AVR was not accompanied by any improvement in cardiovascular autonomic function at least in the shortterm . Thus, despite a high prevalence of ventricular arrhythmias in aortic valve disease patients with substantial left ventricular hypertrophy, there was little to suggest the presence of an arrhythmogenic substrate. The potential mechanism of sudden death in these patients could be speculated on the basis of impaired cardiovascular autonomic function

Lessons from helminth infections: ES-62 highlights new interventional approaches in rheumatoid arthritis

Parasitic worms are able to survive in their mammalian host for many years due to their ability to manipulate the immune response by secreting immunomodulatory products. It is increasingly clear that, reflecting the anti-inflammatory actions of such worm-derived immunomodulators, there is an inverse correlation between helminth infection and autoimmune diseases in the developing world. As the decrease in helminth infections due to increased sanitation has correlated with an alarming increase in prevalence of such disorders in industrialised countries, this "Hygiene Hypothesis" has led to the proposal that worms and their secreted products offer a novel platform for the development of safe and effective strategies for the treatment of autoimmune disorders. Here we review the anti-inflammatory effects of one such immunomodulator, ES-62 on innate and adaptive immune responses and the mechanisms it exploits to afford protection in the murine Collagen Induced Arthritis (CIA) model of rheumatoid arthritis (RA). As its core mechanism involves targeting of IL-17 responses, which despite being pathogenic in RA are important for combating infection, we discuss how its selective targeting of IL-17 production by Th17 and γδ T cells, whilst leaving that of CD49b+ Natural Killer (NK and NK T) cells intact, reflects the ability of helminths to modulate the immune system without immunocompromising the host. Exploiting helminth immunomodulatory mechanisms therefore offers the potential for safer therapies than current biologics, such as "IL-17 blockers", that are not able to discriminate sources of IL-17 and hence present adverse effects that limit their therapeutic potential