PERFORMANCE EVALUATION OF DIGITAL GOVERNOR FOR IMPROVING OPERATIONAL EFFICIENCY AND RELIABILITY OF POWER PLANT

 In this paper, response of newly installed digital governor of Tarbela Power Station has been checked. During testing different parameter like speed of the hydro generator after load rejection, step response of MW, relief valve timing were checked and comparison of previous installed electromechanical governor is also illustrated. Previously in Tarbela, Electromechanical Governor was installed which was replaced with digital governor in 2014. This newly installed Governor has Mark VIe Control System which is designed by G.E (USA) for retrofitting the turbine control system at Tarbela. The Mark VIe software is easy-to-use for configuration and diagnostic tools aid in the startup and maintenance of the system. Digital governors are more cost-effective in the long haul as compared to the electromechanical governor as they are maintenance free. In case of failure of any electronic component, the replacement process is very simple. Testing of all field devices of the digital governor is very easy to use and can be easily maintain over the years. The accuracy of the digital devices is very high and also plays a pivotal role. It is true that mechanical devices can be reliable and accurate, but the digital ones are definitely superior in terms of accuracy

Indoleamine 2,3- Dioxygenase: A Novel Immunotherapeutic Target for Osteosarcoma

Introduction: Tumour-emitted molecules induce immunosuppression in the tumour microenvironment. An immunosuppressive enzyme, indoleamine 2,3-dioxygenase (IDO/IDO1), facilitates immune escape in several malignant tumours, including osteosarcoma. Upregulation of IDO establishes a tolerogenic environment in the tumour and the tumour-draining lymph nodes. IDO-induced downregulation of effector T-cells and upregulation of local regulatory T-cells creates immunosuppression and promotes metastasis. Observations: Osteosarcoma is the most common bone tumour characterised by immature bone formation by the tumour cells. Almost 20% of osteosarcoma patients present with pulmonary metastasis at the time of diagnosis. The improvement in therapeutic modalities for osteosarcoma has been in a stagnant phase for two decades. Therefore, the development of novel immunotherapeutic targets for osteosarcoma is emergent. High IDO expression is associated with metastasis and poor prognosis in osteosarcoma patients. Conclusion and Relevance: At present, only a few studies are available describing IDO’s role in osteosarcoma. This review describes the prospects of IDO not only as a prognostic marker but also as an immunotherapeutic target for osteosarcoma

Post-Pericardiotomy Syndrome Disguised as Fever of Unknown Origin

Introduction: Post -Pericardiotomy syndrome (PPS) is a clinical diagnosis characterized by fever, pericardial or pleural effusions, and a pericardial friction rub occurring over several days after cardiac surgery. The infrequency of PPS can cause delay in recognition and management, thus leading to significant morbidity. We present a case of fever of unknown origin, pericardial and pleural effusion secondary to postpericardiotomy syndrome 10 days after an Aortic Valve Replacement (AVR) Poster presented at: American College of Physicians Southeast Regional Meeting on October 15th, 201

Changes in Liver Fibrosis as Determined by FIB-4 Score Following Sofosbuvir-Based Treatment Regimes Without Interferon

Objective: To determine the mean change in liver fibrosis as evaluated using the FIB-4 score following Sofosbuvir based treatment regimens without interferon. Methodology: This prospective observational study was conducted at the Department of Medicine, Federal Government Services Hospital, Islamabad, from January 09, 2019 to January 03, 2020. A total of seventy (n=70) patients of either gender between age 18-75 years who were diagnosed with cases of HCV infection were enrolled in this study. All patients were treated with Sofosbuvir-based treatment regimens and were assessed for liver fibrosis using the FIB-4 score at baseline, at end of treatment (EOT) and 12 weeks after EOT. Results: The mean FIB-4 score at baseline was 2.45±0.42, at EOT was 1.0981±0.33 and at 12 weeks after EOT was 1.51±0.32.  As compared to the baseline, the mean FIB-4 score was significantly lesser at EOT (P=0.001) and at 12 weeks after EOT (P=0.001). A similar trend was observed across all stratified groups, i.e., age, gender, and type of patients (P<0.05 across all groups). Conclusion: The sofosbuvir-based treatment regimen significantly reduced liver fibrosis at EOT and 12 weeks after EOT, as evidenced by FIB-4 scores that were significantly lower than baseline at EOT and 12 weeks after EOT

PERFORMANCE EVALUATION OF DIGITAL GOVERNOR FOR IMPROVING OPERATIONAL EFFICIENCY AND RELIABILITY OF POWER PLANT

 In this paper, response of newly installed digital governor of Tarbela Power Station has been checked. During testing different parameter like speed of the hydro generator after load rejection, step response of MW, relief valve timing were checked and comparison of previous installed electromechanical governor is also illustrated. Previously in Tarbela, Electromechanical Governor was installed which was replaced with digital governor in 2014. This newly installed Governor has Mark VIe Control System which is designed by G.E (USA) for retrofitting the turbine control system at Tarbela. The Mark VIe software is easy-to-use for configuration and diagnostic tools aid in the startup and maintenance of the system. Digital governors are more cost-effective in the long haul as compared to the electromechanical governor as they are maintenance free. In case of failure of any electronic component, the replacement process is very simple. Testing of all field devices of the digital governor is very easy to use and can be easily maintain over the years. The accuracy of the digital devices is very high and also plays a pivotal role. It is true that mechanical devices can be reliable and accurate, but the digital ones are definitely superior in terms of accuracy

The Interplay Between Pore‐Scale Heterogeneity, Surface Roughness, and Wettability Controls Trapping in Two‐Phase Fluid Displacement in Porous Media

Predicting the compactness of the invasion front and the amount of trapped fluid left behind is of crucial importance to applications ranging from microfluidics and fuel cells to subsurface storage of carbon and hydrogen. We examine the interplay of wettability, macro‐ and pore scale heterogeneity (pore angularity and pore wall roughness), and its influence on flow patterns formation and trapping efficiency in porous media by a combination of 3D micro‐CT imaging with 2D direct visualization of micromodels. We observe various phase transitions between the following capillary flow regimes (phases): (a) compact advance, (b) wetting and drainage Invasion percolation, (c) Ordinary percolation

A cross sectional study on the risk factors of gallbladder stone

Background: Gallstone diseases are one of the most common public health problems. Approximately 10%-20% of the national adult populations currently carry gallstones, and gallstone prevalence is rising. The purpose of the study was to find out association of gallstone with fatty liver, gender and age in Lahore, Pakistan.Methods: Ultrasonographically Hundred patients were scanned for liver type and gall stone. The data was analyzed by using SPSS version 17.0. Chi-Square statistics was used to check the association between the variables. The effect of age and gender was also statistically analysed.Results: One hundred patients were scanned between ages 21-60 years. Out of hundred 76% patients were female and 24% were male. In this study there were no stones in 37% cases and there were stones in 63% cases. Gallbladder stone found associated with age as p-value is found less than 5% level of significance, maximum patients were found in age ranges between 31-35 years, showing that risk of developing gallstone increases by age. Gallstone is gender specific, females are more victims of developing the stone than among males, and those who have fatty liver are more at risk of developing gallstone than those having normal liver.Conclusions: The study showed that ultrasound (US) is the most sensitive, specific, yet very practical and useful imaging test for the detection of gallstones with a high degree of confidence. Gallstones represent high prevalence disease in adult females more than males and it increases by age where as those who have fatty liver, they are more likely to develop gallstone

Ameliorating drought effects in wheat using an exclusive or 2 co-applied rhizobacteria and ZnO nanoparticles

Simple Summary Wheat is a vital source of food, and its production is increasingly threatened by drought episodes. Moreover, its cultivation under water deficit situations along with zinc deficient soils is a major concern of declined wheat grain quantity and quality. Drought-linked changes in nutrient use efficiency, photosynthetic mechanisms, and chemical composition of wheat plants ultimately led to poorer harvest. Therefore, we aimed to understand the drought-ameliorating and grain nutritional improving effects in wheat by rhizobacteria (Azospirillum brasilense) and ZnO nanoparticles (NPs) under various growth stage-based drought stress episodes. Rhizobacteria colonized the host plant rhizosphere and provided growth promotion and stress amelioration. ZnO NPs were recognized as a potential water and zinc deficiency alleviator, and general growth promoter by triggering nitrogen metabolism, chlorophyll synthesis, membrane integrity, and grain zinc biofortification activities. Physio-biochemical observations indicated significantly higher positive effects under co-application over the sole use of either microbial or nanomaterials. Based on our research, it was concluded that co-applied Azospirillum brasilense and ZnO NPs generally increase wheat productivity under drought episodes with low operational cost to growers. Further, plausible synergistic physiological enhancement by NPs and rhizobacteria interaction may contribute towards sustainable wheat crop management under abiotic stresses. Drought is a major abiotic factor and affects cereal-based staple food production and reliability in developing countries such as Pakistan. To ensure a sustainable and consistent food supply, holistic production plans involving the integration of several drought mitigation approaches are required. Using a randomized complete block design strategy, we examined the drought-ameliorating characteristics of plant growth-promoting rhizobacteria (PGPR) and nanoparticles (NPs) exclusively or as a combined application (T-4) through three stages (D-1, D-2, and D-3) of wheat growth (T-1, control). Our field research revealed that Azospirillum brasilense alone (T-2) and zinc oxide NPs (T-3) improved wheat plant water relations, chlorophyll, proline, phenolics and grain quality, yield, and their allied traits over the stressed treatments. Specifically, the best outcome was observed in the combined treatment of PGPR and ZnO NPs (T-4). Interestingly, the combined treatment delivered effective drought mitigation through enhanced levels of antioxidants (15% APX, 27% POD, 35% CAT, 38% PPO and 44% SOD) over controls at the grain-filling stage (GFS, D-3 x T-1). The 40% improvements were recorded under the combined treatment at GFS over their respective controls. Their combined usage (PGPR and ZnO NPs) was concluded as an effective strategy for building wheat resilience under drought, especially in arid and semi-arid localities

The Influence of Board Characteristics on Shareholders Assessment of Risk for Small and Large Firms: Evidence from Pakistan

This unique study examines the alliance between board characteristics and shareholders assessment of risk as revealed in the volatility of stock returns for Pakistani listed companies. For this purpose, a sample of 30 manufacturing companies is used that are listed on Karachi Stock Exchange for the period of 2004 to 2013.  The study uses panel data analysis and reports that random effect model is the best results yielding method. Our hypothesis incorporates preceding evidence that the small and large firms have spectacularly diverse constitution of boards, shimmering the firms diverse monitoring and counseling needs. It is hypothesized and locate confirmation with the intention of entrenched the large firms are able to produce affirmative net benefits, in the appearance of lesser risk, form board independence, gender diversity and director ownership. On the other hand the finding of this study showed the board size is negatively associated with the shareholder assessment of risk for large firms and the positive associated with the assessment of risk for small firms. The CEO duality is positive associated with the assessment of risk for large and negative associated amid assessment of risk for small firms. The results have insinuation for regulatory authorities, shareholders and directors to take steps to improve the board competanices for better performance. Keywords: Board Characteristics, Shareholders Assessment of Risk, Panel Data Analysis, Karachi Stock Exchange JEL Classifications: G32, G34, G38

A New Phase Diagram for Fluid Invasion Patterns as a Function of Pore‐Scale Heterogeneity, Surface Roughness, and Wettability

Understanding how different flow patterns emerge at various macro‐ and pore scale heterogeneity,pore wettability and surface roughness is remains a long standing scientific challenge. Such understandingallows to predict the amount of trapped fluid left behind, of crucial importance to applications ranging frommicrofluidics and fuel cells to subsurface storage of carbon and hydrogen. We examine the interplay ofwettability and pore‐scale heterogeneity including both pore angularity and roughness, by a combination ofmicro‐CT imaging of 3D grain packs with direct visualization of 2D micromodels. The micromodels aredesigned to retain the key morphological and topological properties derived from the micro‐CT images.Different manufacturing techniques allow us to control pore surface roughness. We study the competitionbetween flow through the pore centers and flow along rough pore walls and corners in media of increasingcomplexity in the capillary flow regime. The resulting flow patterns and their trapping efficiency are in excellentagreement with previous μ‐CT results. We observe different phase transitions between the following flowregimes (phases): (a) Frontal/compact advance, (b) wetting and drainage Invasion percolation, and (c) Ordinarypercolation. We present a heterogeneity‐wettability‐roughness phase diagram that predicts these regimes