Effect of alcohol-treated CO2 on interfacial tension between CO2 and oil, and oil swelling

This paper investigates the extent to which alcohol-treated carbon dioxide (CO2 ), a mixture of alcohol and CO2 equilibrated at experimental pressure and temperature, can lead to greater interfacial tension reduction and greater oil swelling than can pure CO2 . Experimental measurements of interfacial tension and swelling behavior are made using a high-pressure, high-temperature visual cell at 70 °C. Two sets of fluid pairs are used: pure CO2 and oil, and alcohol-treated CO2 and oil. Two types of oil are used: a mixture of 35% hexane and 65% decane (C6 -C10 mixture), and pure decane (pure C10 ). Ethanol and methanol are used to prepare alcohol-treated CO2 . Numerical simulations are used to estimate a reduction in the minimum miscibility pressure when using alcohol-treated CO2 . Interfacial tension between alcohol-treated CO2 and oil is found to be 0.02 to 2.2 mN/m less than that between pure CO2 and oil. Simulation results suggest that alcohol-treated CO2 yields 0.2 to 1.2 MPa lower minimum miscibility pressure compared to pure CO2 . Alcohol-treated CO2 also is found to cause 6% to 43% more swelling of oil than does pure CO2 . Interfacial tension and swelling results suggest that alcohol-treated CO2 yields better miscibility with oil compared to pure CO2 .Cited as: Saira, Yin, H., Le-Hussain, F. Effect of alcohol-treated CO2 on interfacial tension between CO2 and oil, and oil swelling. Advances in Geo-Energy Research, 2021, 5(4): 407-421, doi: 10.46690/ager.2021.04.0

Effect of fines migration on oil recovery from carbonate rocks

We perform single-phase and two-phase flooding on Edwards Brown rock samples. The single-phase injection was of seawater or CaCl2 brine, at successive salinities 0.63, 0.21, 0.07, 0.05, and 0 mol/L (distilled water). For CaCl2 brine experimental run, no significant fines migration or permeability decrease is observed. For seawater experimental run, distilled water injection is found to bring about the highest concentration of produced fines and most of the permeability decrease, with the ultimate permeability decrease being 99.94%. Therefore, distilled water injection is used to stimulate fines migration in the following two-phase experimental runs. Two-phase experiments are performed on four Edwards Brown rock samples using seawater or CaCl2 brine as the aqueous phase, and Soltrol® 130 or crude oil as the oleic phase. Rock samples are initially fully saturated with 0.63 mol/L of the selected aqueous solution. This is followed by injecting the selected oil at a constant rate for at least 20 pore volumes to displace brine. Next, selected brine is injected to displace oil, and finally distilled water. For CaCl2 brine, distilled water injection is found to recover no additional oil of either type of oil. However, for seawater, the fines production observed during distilled water injection is found to reduce water relative permeability by two orders of magnitude when Soltrol® 130 is used and by three orders of magnitude when crude oil is used. The seawater experimental runs also brought about additional oil recovery during distilled water injection: 18% when Soltrol® 130 is used and 3.4% when crude oil is used. This last result can be attributed to the plugging of pores due to fines migration, which can divert further injected water into previously unswept pores. Cited as: Almutairi, A., Saira, S., Wang, Y., Le-Hussain, F. Effect of fines migration on oil recovery from carbonate rocks. Advances in Geo-Energy Research, 2023, 8(1): 61-70. https://doi.org/10.46690/ager.2023.04.0

Is it T3 thyrotoxicosis? A case of falsely elevated tri-iodothyronine (T3) levels leading to a diagnosis of multiple myeloma

We are presenting a case of falsely elevated T3 levels in a patient due to interference from monoclonal immunoglobulins. A 56-year-old, clinically euthyroid man referred to the endocrinology clinic of the Aga Khan university, Karachi Pakistan, for possible T3 thyrotoxicosis after thyroid function tests revealed total T3 \u3e12.32 nmol/L (reference range 0.6-2.79), normal TSH, and total T4 level. There was a mismatch in clinical and laboratory parameters and preliminary laboratory results were suggestive of thyroid binding globulin abnormalities. Further evaluation in this context unmasked multiple myeloma. The presence of monoclonal immunoglobulins can lead to assay interference and spurious results. To the best of our knowledge, this is the second case defining the cause of falsely elevated T3 levels, due to assay interferences with binding of T3 only to monoclonal immunoglobulins

Conversion of autoimmune hypothyroidism to hyperthyroidism

Background: Graves\u27 disease and Hashimoto\u27s thyroiditis are the two autoimmune spectrum of thyroid disease. Cases of conversion from hyperthyroidism to hypothyroidism have been reported but conversion from hypothyroidism to hyperthyroidism is very rare. Although such cases have been reported rarely in the past we are now seeing such conversions from hypothyroidism to hyperthyroidism more frequently in clinical practice. Case Presentation: We are reporting three cases of middle aged Asian females who presented with classical symptoms of hypothyroidism and the investigations showed elevated thyroid stimulating hormone with positive thyroid antibodies. Diagnosis of autoimmune hypothyroidism was made and thyroxine replacement therapy was initiated. Patients became asymptomatic with normalization of thyroid stimulating hormone level. After few years they developed symptoms of hyperthyroidism with suppressed thyroid stimulating hormone level. Over replacement of thyroxine was considered and the dose of thyroxine was decreased, but they remain symptomatic. After gradual decrease in the dose of thyroxine it was stopped finally. Even after few months of stopping thyroxine, the symptoms of hyperthyroidism did not improve and the biochemical and imaging modalities confirmed that the patients have developed hyperthyroidism. Anti-thyroid treatment was then started and the patients became symptom free. Conclusion: High index of suspicion should be there for possible conversion of hypothyroidism to hyperthyroidism if a patient with primary hypothyroidism develops persistent symptoms of hyperthyroidism. Otherwise it can be missed easily considering it as an over replacement with thyroid hormone

Dengue fever presenting as quadriparesis due to hypokalaemia: a rare presentation

Dengue is one of the leading causes of arthropod borne viral haemorrhagic fever. Majority of the times, it clinically manifests as fever, arthralgia and rash; however, we present a case of a young man who presented with progressively increasing weakness of all four limbs. Initial investigations showed low potassium, hence he was managed as hypokalaemic periodic paralysis. With initial history of fever and low platelets, dengue was suspected. Dengue antibody was checked which came out to be positive. Potassium was replaced which led to improvement in power of his limbs. He was discharged in a stable condition with a diagnosis of dengue with hypokalaemic quadriparesis

Relationship between estimated average glucose (eAG) and fasting plasma glucose in a cohort of Pakistani diabetic subjects

Introduction: Scientific literature is scarce on the utility of estimated average glucose (eAG) from Pakistan. Hence, there is a dire need to evaluate the relationship between eAG and fasting plasma glucose (FPG), in order to enhance our understanding of eAG and its usefulness. This study aims to investigate the relationship between FPG and eAG in diabetic patients calculated using HbA1C.Materials and methods: A retrospective study was conducted at the Aga Khan University, Karachi, Pakistan. The medical records of both genders in the age range of 18-60 years, presenting as outpatients at the endocrine clinic, labeled as DM, were reviewed from January 2013 to December 2019. The subjects were divided into three groups A (\u3c130 mg/Dl), B (130-179 mg/Dl), and C (\u3e180 mg/Dl) based on FPG levels. A correlation was compared using Spearman’s correlation. Box, whisker plots, and scatter plots were computed by R studio.Results: After excluding those with missing values for either serum Cr, FPG, and HbA1c and sub-optimal renal function based on estimated glomerular filtration rate (eGFR) a total of 4,673 cases were analyzed. Subgroup A showed good glycemic control, whereas subgroup C showed poor glycemic control. The difference between eAG and FPG was significant (p \u3c 0.0001). eAG values were found to be elevated than FPG values in groups A and B and almost the same in group C, whereas a moderately significant correlation with eAG and FPG in all three groups.Conclusion: The correlation between eAG and FPG varies with blood glucose control and was significantly higher in the poorly controlled diabetes group. As the association between the FPG and eAG levels varies with the extent of blood glucose control, reporting eAG with HbA1c by a simple formula, at no additional cost will prove to be beneficial for clinical care

Facial expression recognition using lightweight deep learning modeling

Facial expression is a type of communication and is useful in many areas of computer vision, including intelligent visual surveillance, human-robot interaction and human behavior analysis. A deep learning approach is presented to classify happy, sad, angry, fearful, contemptuous, surprised and disgusted expressions. Accurate detection and classification of human facial expression is a critical task in image processing due to the inconsistencies amid the complexity, including change in illumination, occlusion, noise and the over-fitting problem. A stacked sparse auto-encoder for facial expression recognition (SSAE-FER) is used for unsupervised pre-training and supervised fine-tuning. SSAE-FER automatically extracts features from input images, and the softmax classifier is used to classify the expressions. Our method achieved an accuracy of 92.50% on the JAFFE dataset and 99.30% on the CK+ dataset. SSAE-FER performs well compared to the other comparative methods in the same domain

Adolopment of adult diabetes mellitus management guidelines for a Pakistani context: Methodology and challenges

IntroductionPakistan has the highest national prevalence of type 2 diabetes mellitus (T2DM) in the world. Most high-quality T2DM clinical practice guidelines (CPGs) used internationally originate from high-income countries in the West. Local T2DM CPGs in Pakistan are not backed by transparent methodologies. We aimed to produce comprehensive, high-quality CPGs for the management of adult DM in Pakistan.MethodsWe employed the GRADE-ADOLOPMENT approach utilizing the T2DM CPG of the American Diabetes Association (ADA) Standards of Medical Care in Diabetes – 2021 as the source CPG. Recommendations from the source guideline were either adopted as is, excluded, or adapted according to our local context.ResultsThe source document contained 243 recommendations, 219 of which were adopted without change, 5 with minor changes, and 18 of which were excluded in the newly created Pakistani guidelines. One recommendation was adapted: the recommended age to begin screening all individuals for T2DM/pre-diabetes was lowered from 45 to 30 years, due to the higher prevalence of T2DM in younger Pakistanis. Exclusion of recommendations were primarily due to differences in the healthcare systems of Pakistan and the US, or the unavailability of certain drugs in Pakistan.ConclusionA CPG for the management of T2DM in Pakistan was created. Our newly developed guideline recommends earlier screening for T2DM in Pakistan, primarily due to the higher prevalence of T2DM amongst younger individuals in Pakistan. Moreover, the systematic methodology used is a significant improvement on pre-existing T2DM CPGs in Pakistan. Once these evidence based CGPs are officially published, their nationwide uptake should be top priority. Our findings also highlight the need for rigorous expanded research exploring the effectiveness of earlier screening for T2DM in Pakistan