Numerical modelling of two-phase flow through heterogeneous porous media into water column

This research focuses on the development of the self-consistent numerical model to predict the two-phase plume dynamics developed through porous media into the fluid media flow field. The engineering background of this study is the dynamics of upward migration of CO2 plume through superimposing complex structures and residues in seabed sediments into the ocean bottom boundary layer. A model called as ‘An arbitrary Navier-Stokes-Darcy multi-fluid flow model (AnsdMF) was developed to automatically incorporate the fluids flow through the complex geoformations, where either the nonlinear convection dominates or Darcy’s law dominates, into the turbulent ocean. The model was developed on the basis of OpenFOAM platform. This study is part of the research of EU project STEMM-CCS*. Sub-models are developed for mass transfer in porous media with an effective interfacial area using data from laboratory experiments. The models are calibrated with data from the experimental laboratory of CO2 gas dispersion through standard sediments. A method of reconstruction of complex sediment by using the data from field observations is proposed and applied for the model setting of the complex structured sediments for simulations of field experiments carried by STEMM-CCS project. The developed model (AnsdMF) is then applied to investigate the fluid pathways within geoformation structures without chimneys (NC), with unconnected chimneys (UCC), and connected chimneys (CC). It is found from the investigation that the CC provides fast pathways to gas dispersion, 3.8 times faster than that through a UCC and 12.8 times faster than that through an NC. In comparison with the results from Darcy model, the similar velocity pattern identified inside the sediments when no cracks were present, with the maximum velocity of 2.0 x 10-4m/s in the case of AnsdMF model as compared 1.1 x 10- 4m/s. The difference is from the contributions of nonlinear convection modelled by AnsdMF model. The developed model (AnsdMF) is then applied to simulate the field experiment carried out by STEMM-CCS project to predict the dynamics from CO2 injection, dispersion, and dissolution in sediment, and finally leakage into ocean bottom boundary layer. In comparison with the data obtained from the field, it shows that the model has successfully predicted CO2 plume developments in complex sediments, including dissolved/undissolved CO2 inside the sediments and the rates of CO2 leakage. It is found that the role of the ‘chimney’ structure on CO2 dispersion is clearly demonstrated, through which, the injected CO2 disperses to the seafloor within 16 minutes. The results show that total 150 Kg of gas is stored inside the sediments while the peak dissolution rate of 0.2g/s in the first hour of gas injection (at a rate of 5.7 Kg/sec) confirming most of the dissolution of CO2 into porewater occurred within this time period. The rest of the gas found the migratory path through overlying clay in the fracture or pockmarks reach to a leakage rate of 5.5 Kg/day. The leakage rate into the ocean bottom boundary layer starts from a single stream of bubbles at ~2.1 Kg/Sec and settles at ~5.1 Kg/Sec after 2 hours of gas release. The leakage and gas release rates found in a similar range results in a relative to the constant volume of the plume in sediments with a gas dissolution ratio of 0.038. When the gas injection rate increases from 29 Kg/day to 143 Kg/day, the horizontal size of gas plume also increases from 4.92m to 6.51m. *STEMM-CCS: Strategies for Environmental Monitoring of Marine Carbon Capture and Storage. European Union’s Horizon 2020 research and innovation programme under grant agreement No. 654462

Preclinical evaluation of pharmacological strategies designed to enhance the activity of established and novel anti-cancer drugs. Synopsis: Evaluation of pharmacological strategies designed to modulate the Warburg effect, enhance the activity of tyrosine kinase inhibitors and novel analogues of Temozolomide.

Whilst progress has been made in reducing mortality in some cancers, mortality rates remain high in many cancers and there is a need to develop novel therapeutic strategies. In this thesis, various pharmacological strategies designed to enhance the activity of existing therapeutic drugs were evaluated. Cancer cells are dependent upon aerobic glycolysis (the Warburg effect) and glutamine uptake. Using clinically approved tyrosine kinase inhibitors and Bortezomib, significant enhancement of chemosensitivity was observed when used in combination with inhibitors of lactate dehydrogenase (Gossypol) and pyruvate kinase dehydrogenase (Dichloroacetate). In contrast, depletion of glutamine from media had to be extensive in order to induce cell death and cell death only occurred after prolonged exposure to glutamine-deprived conditions. This suggests that glutamine depletion strategies alone are unlikely to be successful but may be useful in combination with other agents targeting glutamine addiction in cancer cells. Finally, Temozolomide (TMZ) is an important drug in the treatment of glioblastomas but its activity is reduced by resistance mechanisms including O6 methyl guanine methyltransferase (MGMT) and mismatch repair (MMR). This thesis has identified analogues of TMZ (EA02-45, EA02-59, EA02-64 and EA02-65) that are MGMT and MMR independent in terms of inducing cell kill in vitro. These compounds are promising leads for future development. In conclusion, this thesis has demonstrated that interfering with the metabolic phenotype of cancer can enhance the activity of existing drugs and identified novel analogues of TMZ that circumvent drug resistance mechanisms that hamper the efficacy of TMZ

Using Remote Sensing for Identifying Suitable Areas for Flood Shelter: A Case Study of Thatta, Sindh Pakistan

The most recurring type of disaster in the world these days is flood because of the spread and extent of its effect on people, among all-natural disasters of the world. Human activities have paved the way for many of these flood behavior to change as they used to be in the past. Pakistan experienced one of the most devastating natural disasters in its history all across the country in 2010, but Thatta district in southern part got severely affected during this flood. For the research, a simple yet efficient methodology Normalized Difference Vegetation Index (NDVI) by using remote sensing images for identifying flood hazard areas was utilized. Geographic Information Systems (GIS) helps in finding shelter areas with a minimum effect of floods. It is essential to realize the importance of mapped results in consideration of manual flood management in future. The method used in this study is robust enough to explain the flood hazard for suggesting suitable shelter sites in case of flooding events. This would help disaster management bodies and other related agencies to formulate the development plans while keeping the hazard areas, which are unsuitable for development due to flood risk in the future

Pre-operative Anxiety Compounding Intra-operative Hypotension in Parturient women undergoing Cesarean Deliveries under Spinal Anesthesia

OBJECTIVE: To assess the relation of intra-operative hypotension with severity of pre-operative anxiety in patients undergoing caesarean section under spinal anesthesia. STUDY DESIGN: Prospective observational study. PLACE AND DURATION OF STUDY:  This study was carried out from June 2017 to May 2018 at anesthesia department of Combined Military Hospital Lahore. METHODOLOGY: One hundred and twenty patients belonging to America Society of Anesthesiology class I and II, undergoing caesarean section under spinal anesthesia were selected.  Verbal Analogue Scale for anxiety (VASA) and Straight Trait Anxiety Inventory (STAIs) questionnaire were used to measure pre-operative anxiety. Patients were divided into three groups as mild (VASA<3or STAIs<44), moderate (VASA 4-7 or STAIs 44-55) and severe (VASA 7-10 or STAIs>55) anxiety. Baseline mean arterial pressure was measured. Patients were placed in supine position immediately after induction of spinal anesthesia at L3-L4 or L4-L5 level with 12mg bupivacaine. Blood pressure was measured every two minutes until the delivery of baby. Hypotension was labeled when mean arterial pressure dropped by 20% below the baseline. The effect of level of anxiety on drop in MAP was assessed. RESULTS: Seventeen (14.17%) patients had mild pre-operative anxiety; out of which four (23.53%) developed hypotension. Seventy three (60.83%) patients had moderate anxiety; out of which twenty seven (36.99%) developed hypotension. Thirty (25%) patients had severe anxiety; out of which twenty two (73.33 %) developed hypotension. P-value (0.001) was quite significant. CONCLUSION:  It was concluded in our study that severity of pre-operative anxiety has significant effect on intra-operative spinal hypotension

Acute presentation of cocoon abdomen as septic peritonitis mimicking with strangulated internal herniation: A case report

Background: Abdominal cocoon syndrome is a rare cause of intestinal obstruction in which loops of small bowel get entrapped inside a fibro-collagenous membrane. Condition is also known in the literature as sclerosing peritonitis and in the majority of cases, it has no known cause. Although the majority of patients exhibit long-standing signs and symptoms of partial bowel obstruction in an out-patient clinic, its acute presentation in the emergency room with features of sepsis is extremely rare. This case report aims to describe the emergency presentation of cocoon abdomen with septic peritonitis.Case presentation: A 35-year-old male with no known co-morbidity and no prior history of prior laparotomy presented in emergency room first time with a 1-day history of generalized abdomen pain, vomiting, and absolute constipation. He was in grade III shock and had metabolic acidosis. The clinical impression was of the perforated appendix, but initial contrast-enhanced computed tomography (CECT) was suggestive of strangulated internal herniation of small bowel. Emergency laparotomy after resuscitation revealed hypoperfused, but viable loops of small bowel entrapped in the sclerosing membrane. Extensive adhesiolysis and removal of the membrane were performed and the entire bowel was straightened. Postoperatively he remained well and discharged as planned. Histopathology report confirms features of sclerosing peritonitis.Discussion: Cocoon abdomen is a very rare cause of acute small bowel obstruction presenting in an emergency with features of septic peritonitis. Condition is mostly chronic and generally mimics abdominal TB in endemic areas like India and Pakistan. A high index of suspicion is required in an emergency setting and exploratory laparotomy is diagnostic and therapeutic as well and the condition mimics internal herniation in acute cases.Conclusion: Cocoon abdomen as a cause of septic peritonitis is extremely rare and might be an unexpected finding at laparotomy. Removal of membrane and estimation of the viability of entrapped bowel loops is the treatment of choice, which may require resection in the extreme case of gangrene

Comparison of first dorsal metacarpal artery flap done by consultants and residents and guidelines for improving outcome for beginners

Background: Thumb alone constitutes about 40% of hand function and trauma to distal part of thumb will thus affect the overall hand function. The goals of correction of traumatic deformities of distal thumb are to maintain adequate length and sensation along with giving a supple and stable soft tissue cover. Among other options, first dorsal metacarpal artery (FDMA) flap raised from the dorsum of the proximal part of index finger is a simple and widely used flap.Methods: We compared the results of FDMA flap done by residents (M.Ch trainees) and consultants in our institute. Residents operated upon a total of 12 patients and consultants operated upon 16 patients.Results: Among 12 patients operated by residents 3 flaps were lost and 2 flaps had marginal necrosis whereas among the patients operated by consultants 1 flap was lost and 1 had partial necrosis in distal part of the flap.Conclusions: Although there was no statistical difference between the operating time taken by trainees and consultant specialists but the complication rate is higher among the residents. Sticking with the basics of plastic surgery, FDMA flap is an excellent technique for thumb reconstruction and results are excellent as and when more experience is gained

Oral Health Status of Pregnant Women and their Referral to Dentist during Antenatal Period

AbstractObjective: The aim of this study was to assess oral health status of pregnant women and theirreferral to dentist during antenatal period.Methodology: This descriptive cross-sectional study was conducted in Outpatient Department,(Gynae and Obs.) Jinnah Hospital Lahore, Pakistan after ethical committee approval. The sample sizewas calculated using formula for finite population and found to be 340 pregnant women who wereconveniently sampled and interviewed by using a self-administered questionnaire following verbaland written consent. Oral health status was examined clinically using dental mirror and Michiganprobe. Scoring was done using WHO oral health assessment form for adults, 2013 includingCommunity periodontal index, DMFT, and Dean's fluorosis index. Data was statistically analyzedusing SPSS version 24. Chi-square test was applied to compare categorical variables (p≤ 0.05 assignificant).Results: Total 236 (69.4%) out of 340 pregnant women had oral health problems. Only 11 (3.2%)participants were referred by the gynaecologist to dentist for their oral health issue. Out of 236participants, 67% had dental caries, 80.9% had gingival bleeding, 58.8% had gingival pockets, 41.7%had loss of attachment, 1.8% had dental erosions, 63.8% had dental fluorosis and 1.5% had oralmucosal lesions. The majority of pregnant women who participated in this study had lowsocioeconomic status (mean income PKR 20300±10304.14) reported with more oral health problems.Conclusion: As reported in this study, majority of pregnant women had oral health problems andonly few of them were referred to dentist by gynaecologist.Key Words: Pregnant women, Oral health status, Gynaecologist, Antenatal perio

ERBM-SE: Extended Restricted Boltzmann Machine for Multi-Objective Single-Channel Speech Enhancement

Machine learning-based supervised single-channel speech enhancement has achieved considerable research interest over conventional approaches. In this paper, an extended Restricted Boltzmann Machine (RBM) is proposed for the spectral masking-based noisy speech enhancement. In conventional RBM, the acoustic features for the speech enhancement task are layerwise extracted and the feature compression may result in loss of vital information during the network training. In order to exploit the important information in the raw data, an extended RBM is proposed for the acoustic feature representation and speech enhancement. In the proposed RBM, the acoustic features are progressively extracted by multiple-stacked RBMs during the pre-training phase. The hidden acoustic features from the previous RBM are combined with the raw input data that serve as the new inputs to the present RBM. By adding the raw data to RBMs, the layer-wise features related to the raw data are progressively extracted, that is helpful to mine valuable information in the raw data. The results using the TIMIT database showed that the proposed method successfully attenuated the noise and gained improvements in the speech quality and intelligibility. The STOI, PESQ and SDR are improved by 16.86%, 25.01% and 3.84dB over the unprocessed noisy speech

Recurrent Cervical Neurofibrosarcoma: A Rare Case of Malignant Peripheral Nerve Sheath Tumor of Head and Neck Region

Neurofibrosarcoma is a malignant peripheral nerve sheath tumor (MPNST). The cervical location of the neurofibrosarcoma is very rare and is less than 1% in the literature. MPNSTs are often associated with neurofibromatosis type 1 (NF1).  We are presenting a case report of 31 years old female, with huge recurrent cervical neurofibrosarcoma on the right side of the neck.  To date, surgical excision followed by chemotherapy and radiotherapy is the treatment of choice which requires a multidisciplinary approach. We excised the above-mentioned cervical neurofibrosarcoma in a piecemeal fashion and discharged the patient on follow-up with the oncology department