shaheen shah - Academia.edu (original) (raw)

Papers by shaheen shah

Renewable Energy and Sustainability

Journal of Petroleum & Environmental Biotechnology, 2017

Chemical reagents such as Lithium base grease, Calcium base grease, Aluminum base grease which ar... more Chemical reagents such as Lithium base grease, Calcium base grease, Aluminum base grease which are reduced the mechanical friction and increase the performance of machines with adding various additives molybdenum disulphide (MoS 2), Graphite, Boron Nitrite. Dropping point is an indicator of heat resistance of the grease. The dropping point indicates the upper temperature limit at which grease retains its structure. If, failure the grease against high temperature then occurs friction and increase load. When load is increase then the fuel engine does not give the satisfy output. The paper estimated the dropping point of those grease. A.S.T.M standard D-566 used for estimated dropping of the greases. The dropping point of Lithium base grease, Calcium base grease, Aluminum base grease are estimated 195°C, 95°C, and 110°C respectively. The dropping point of mixed base grease i.e., Calcium 50% + Lithium 50%, Lithium 50% + Aluminum 50% and Calcium 50% +Aluminum 50% are 140°C, 158°C and 152°C respectively. The dropping of mixed base grease is higher than the individuals of the greases. The use of the calcium base grease also act is a water and repellant and corrosion protective. This paper represents that Aluminum 50% + Calcium 50% mixed base grease is showing the best performance against high temperature with protects the corrosion.

Journal of Natural Gas Science and Engineering, 2021

Abstract The petrophysical evaluation of the Titas gas field (Titas-15) has been carried out for ... more Abstract The petrophysical evaluation of the Titas gas field (Titas-15) has been carried out for its reservoir characterization and to quantify the reservoir hydrocarbon prospects and gas productivity. The Quick Log Analysis Tool (QLAT) of PE2 Essentials software has been utilized for the computer-processed interpretation inputting the various well log data such as gamma-ray (GR), density log (RHOB), density-porosity (DPHI), neutron porosity (NDHI), resistivity logs, etc. Among the three reservoir sand groups, three gas-bearing sub-zones have been identified in the upper sand group, which are primarily producing gas from the least net-pay of 9.5 m, 39.5 m and 28.5 m, respectively. The shale volume is calculated based on GR, caliper logs and neutron-density (N-D) cross-plot (minimum shale volume) methods whose average value is comprised between 26.3 and 33.9%. The range of effective porosity is 18.4–18.6% indicating a good reservoir quality; permeability is 14.11–25.95 mD; recognizing as the well-sorted nature of sands. Additionally, the hydrocarbon saturation in the respective zones varies from 48% to 60%, suggesting a good hydrocarbon reservoir, whereas the water saturation is 40–52%. Moreover, the range of measured ‘gas initially in place’ in upper, middle and lower gas sands are 2371.6–2579.1, 10330.7–11206.1 and 6373.1–7110.5 MMscf, respectively, implying an adequate gas reserve on commercial criteria. From the evaluation of petrophysical properties, the Titas reservoir has a higher ability to enhance hydrocarbon accumulation and production.

The Professional Medical Journal, 2010

Background: In smooth muscle cells, an increase in cytosolic free calcium concentration is an ess... more Background: In smooth muscle cells, an increase in cytosolic free calcium concentration is an essential step for the cells to contract. The increase in calcium concentration occurs by influx from the extra cellular medium through calcium ion channels. Calcium channels have potential role in regulation of motility in gastrointestinal tract so there is growing interest in calcium channel blockers as a potential pharmacological approach to the treatment of various gastrointestinal motor disorders. In this study we evaluate the inhibitory effects of verapamil on spontaneous contractions of isolated guinea pig ileum and compare them with inhibitory effects of loperamide. Materials and Methods: Isolated intestinal segments of sixteen guinea pigs were used in this study. Serial dilutions (10-18 - 10-3 gm/ml) of loperamide and verapamil were administered; effects observed and recorded by 7B Grass Polygraph machine. Results: We observed that at lower concentrations, loperamide showed more in...

Chemosphere, 2018

For organic pollutants, photodegradation, as a major abiotic elimination process and of great imp... more For organic pollutants, photodegradation, as a major abiotic elimination process and of great importance to the environmental fate and risk, involves rather complicated physical and chemical processes of excited molecules. Herein, we systematically studied the photophysical and photochemical processes of a widely used antibiotic, namely sulfapyridine. By means of density functional theory (DFT) computations, we examined the rate constants and the competition of both photophysical and photochemical processes, elucidated the photochemical reaction mechanism, calculated reaction quantum yield (Φ) based on both photophysical and photochemical processes, and subsequently estimated the photodegradation rate constant. We further conducted photolysis experiments to measure the photodegradation rate constant of sulfapyridine. Our computations showed that sulfapyridine at the lowest excited singlet state (S 1) mainly undergoes internal conversion to its ground state, and is difficult to transfer to the lowest excited triplet states (T 1) via intersystem crossing (ISC) and emit fluorescence. In T 1 state, compared with phosphorescence emission and ISC, chemical reaction is much easier to initiate. Encouragingly, the theoretically predicted photodegradation rate constant is close to the experimentally observed value, indicating that quantum chemistry computation is powerful enough to study photodegradation involving ultra-fast photophysical and photochemical processes.

Strabismus, 2016

The proportion of patients seen by the paediatric eye service that attend for reasons related to ... more The proportion of patients seen by the paediatric eye service that attend for reasons related to amblyopia has not been quantified. The purpose of this study was to quantify the proportion of patients seen in the paediatric eye service attending for reasons related to amblyopia. Records of all eye appointments of children attending the Hillingdon Hospitals NHS Foundation Trust and St Mary&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s Hospital Imperial College Healthcare NHS Trust over one month in 2009 were examined to determine the diagnosis and reason for attendance. Seven hundred and four patients had appointments booked at St Mary&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s and Hillingdon in March 2009. The fail-to-attend rates were not significantly different at the 2 sites (19% at St Mary&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s and 9% at Hillingdon; P=0.75). Of the 704 patients, 533 (St Mary&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s, 252 [75%]; Hillingdon, 281 [76%]) were attending for amblyopia-related reasons. Of the overall 982 booked appointments, 770 (79%) were amblyopia-related. Amblyopia diagnosis and management is clearly the most common cause of attendance to the paediatric eye service, accounting for over three-quarters of outpatient visits.

Clinical & experimental ophthalmology, Jan 19, 2016

not and twelve (12.5%)were undecided. A small number reported new post-operative glare (17/97;17.... more not and twelve (12.5%)were undecided. A small number reported new post-operative glare (17/97;17.5%). Most reported common transient post-operative symptoms such as irritation or dry eyes (89/97;92%). This cross-sectional study suggests that surgical compensation of presbyopia with combined KAMRA inlay insertion and LASIK is well tolerated in an Irish clinic population with most expressing satisfaction with perioperative care and visual outcomes. This paper highlights reasons for selecting the procedure and important potential risks that should be discussed prior, particularly the risk of difficulties with night driving and continued dependency on reading glasses, especially in dim light, and to a lesser degree on distance glasses. Furthermore, a small percentage reported glare and postoperative discomfort. Despite these, most patients reported an improvement in distant, intermediate and near visual tasks and would recommend it to a friend or family member. Although the questionnaire received a relatively high response-rate for an organizational survey, non-response reduces the effective sample size and can introduce bias. Additionally, while anonymous questionnaires allow patients to respond freely, they reduce the ability to interpret results in the context of visual outcomes. Furthermore, no standardized questionnaire was used. However, no validated questionnaire exists and the one used is similar to that used in other studies. Another limitation is that near VA improved as a result of the combination of two procedures. Research is now required to examine long-term satisfaction and quality of life in patients undergoing combined corneal inlay insertion and LASIK. The timing of combined LASIK and inlay insertion and its effect on patient satisfaction should also be examined.

Asia-Pacific Journal of Ophthalmology, 2013

Journal of Ayub Medical College, Abbottabad : JAMC

Physicians are often confronted with patients who state that they are "allergic" to a d... more Physicians are often confronted with patients who state that they are "allergic" to a drug. The goal of this review article is to help physicians to develop management plans for patients who present with drug induced diseases. It provides information that allows physicians to differentiate between reactions that are truly allergic in nature and those that are not immunologically mediated. The suggestions which may be helpful in the assessment are discussed and guidance is provided whether a drug may be safely readministered. Unfortunately until we are unable to thoroughly understand the mechanisms responsible for drug induced reactions, our management tools will remair limited.

Community eye health / International Centre for Eye Health, 2006

Neonatology, 2014

Background: Preterm birth contributes significantly to infant mortality and morbidity, including ... more Background: Preterm birth contributes significantly to infant mortality and morbidity, including blindness from retinopathy of prematurity (ROP). Access to intensive neonatal care is expanding in many countries, but care is not always optimal, one factor being that nursing is often by inadequately trained nurse assistants. Objective: The aim of this study was to evaluate whether an educational package for nurses improves a range of outcomes including survival rates and severe ROP in 5 neonatal units in Rio de Janeiro, Brazil. Methods: The study design included an uncontrolled before-and-after study in 5 units, with interrupted time series analysis. Participatory approaches were used to develop a self-administered educational package for control of pain, oxygenation, infection, nutrition, and temperature and to improve supportive care (‘POINTS of Care'). Educational materials and DVD clips were developed and training skills of nurse tutors were enhanced. There were two 1-year per...

Journal of Rawalpindi …, 2010

Background: To find out the relationship between obesity, sedentary lifestyle and fasting plasma ... more Background: To find out the relationship between obesity, sedentary lifestyle and fasting plasma glucose (FPG)levels in apparently healthy individuals belonging to the paramedical staff of the Liaqat University of Medical and Health Sciences, Jamshoro. Methods: 50 healthy individuals were included in the study. FPG levels were measured at baseline and after three years. Body mass index was calculated as weight in kilograms divided by the square of the height in meters, and the subjects were defined as obese if their BMI was 30 or greater. A specially designed questionnaire NICE guideline-PHI2 Physical activity: Implementation advice 2006 was filled at baseline & at the end of the study. Patients with known DM were excluded from the study. Results: At baseline the mean FPG level was 88 ± 5.62 mg/dl which increased to 98.4 ± 4.22 mg/dl in a three year period. 41% of subjects had FPG of ≥100 when followed up after 3 years. There were two incident cases of DM Type 2. The study revealed that in men with FPG of 100 mg/dL or higher there was a progressively greater risk for type 2 diabetes as the FPG values rose, compared with men who had an FPG of less than 86 mg/dL, p <0.001. A similar large risk was detected in men with a BMI of 30 or more, compared with a BMI less than 25 .It was also observed that most of the subjects were among the moderately inactive group. Conclusion: Persons with normal blood sugar at a given examination, who are over weight and living a sedentary life style; can develop diabetes in coming years as compared to people with less BMI and lower normal fasting plasma glucose levels.

Proceedings of the 13th International Conference on Mechanical Engineering (ICME2019), 2021

The light and medium sized trucks are the main backbone of freight movement in Bangladesh. Most t... more The light and medium sized trucks are the main backbone of freight movement in Bangladesh. Most trucks are typically box shape and built locally on imported chassis by roadside truck body builders with no consideration of aerodynamics, safety (crashworthiness) and environmental impact. Hence, the main purpose of this study is to analyze the aerodynamic aspect of light and medium sized trucks widely used in Bangladesh. The study involves the Computational Fluid Dynamics (CFD) modelling and experimental study using wind tunnel. The study also highlights the safety issues related to light and medium sized trucks. The findings reveal that minor changes in light and medium sized truck body design can reduce aerodynamic drag of nearly one-third thereby lowering fuel consumption and greenhouse gas emission.