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Foam flooding technique, commonly known as foam assisted water alternating gas method (FAWAG) has been identified as an effective chemical enhanced oil recovery (CEOR) technique. The ability of EOR-foam to sweep oil in low permeable zones makes it important displacement fluid in the oil industry. However, extreme reservoir conditions such as temperature, pressure and salinity have detrimental effects on the stability and the overall performance of the EOR-foam. Consequently, understanding foam stability and performance under different conditions is crucial for long term oil field application. This paper discusses the current status of the EOR-foam stability, performance and challenges from laboratory studies to field application perspective. The paper also highlights the knowledge gaps which require further research for successful field application.

In this study, multiphase computational fluid dynamics (CFD) is employed to simulate and study the hydrodynamics behavior of gas-solid mixing in a new bed column design of bubbling fluidized bed called swirl bed. The new fluidized bed is a swirl tube reactor design based on swirl tube technology. The results are compared with the conventional straight tube rector which is the scaled down version of the existing pilot plant gasifier. It is found that the usage of the swirl tube reactor design results in better lateral solid mixing inside the bed. Furthermore an increase in residence time of the particles is also observed due to the swirl motion of the particles.

The aim of the study was to investigate the herb–drug interaction of Andrographis paniculata Nees (Acanthaceae) and Andrographolide (AN) with nabumetone (NAB) in wistar rats. Pharmacokinetic and pharmacodynamic interactions were studied after co-administration of APE and AN with NAB in Wistar rats. In pharmacokinetic studies, significant decrease in Cmax, AUC0–t and AUC0–∞ of 6-MNA after co-administration with pure AN and APE has been observed. Tmax of 6-MNA has been increased to 2 h from 1.5 h in AN + NAB treated group. Changes in mean residential time, clearance and volume of distribution of 6-MNA in APE + NAB treated group and AN + NAB treated group indicated interference of other components of APE other than AN. In pharmacodynamic study, significant decrease in antiarthritic activity of NAB on concomitant administration with APE and AN has been observed. The study concludes that NAB exhibits pharmacokinetic and pharmacodynamic interactions with APE and AN in rats thus alarms the concomitant use of herbal preparations containing APE and AN with NAB. Further study is needed to understand the mechanism and predict the herb–drug interaction in humans.

Ethnopharmacological relevance Andrographis paniculata Nees (Acanthacae) is commonly used medicinal plant in the traditional. Unani and Ayurvedic medicinal systems. It has broad range of pharmacological effects such as hepatoprotective, antioxidant, antivenom, antifertility, inhibition of replication of the HIV virus, antimalarial, antifungal, antibacterial, antidiabetic, suppression of various cancer cells and anti-inflammatory properties. Andrographolide (AN) is one of the active constituent of the A. paniculata Nees extract (APE). They have been found in many traditional herbal formulations in India and proven to be effective as anti-inflammatory drug Aim of the study To evaluate the pharmacokinetic and pharmacodynamic (anti-arthritic) herb–drug interactions of A. paniculata Nees extract (APE) and pure andrographolide (AN) with etoricoxib (ETO) after oral co-administration in wistar rats. Materials and methods After oral co-administration of APE (200 mg/Kg) and AN (60 mg/kg) with ETO (10 mg/kg) in rats, drug concentrations in plasma were determined using HPLC method. The main pharmacokinetic parameters of C max , t max , t 1/2 , MRT, Vd, CL, and AUC were calculated by non-compartment model. Change in paw volume, mechanical nociceptive threshold, mechanical hyperalgesia, histopathology and hematological parameters were evaluated to study antiarthritic activity. Results Co-administration of ETO with APE and pure AN decreased systemic exposure level of each compound in vivo . The C max , AUC, t 1/2 of ETO was decreased whereas Vd and CL of ETO was increased significantly after co-administration of ETO with pure AN and APE. In pharmacodynamic study, ETO alone and ETO+APE (10+200 mg/kg) groups exhibited significant synergistic anti-arthritic activity as compared to groups ETO+AN, APE and AN alone. Conclusion The results obtained from this study suggested that ETO, APE and pure AN existed pharmacokinetic herb–drug interactions in rat which is correlated with anti-arthritic study. Physicians and patients using A. paniculata should have the knowledge about its possible herb–drug interaction with ETO.

Background: The study was conducted to radiologically demonstrate increase in thymus size with clinical recovery following nutritional rehabilitation in children with severe acute Malnutrition and to correlate the improvement with anthropometric and biochemical parameters.Methods: Prospective observational study was conducted in 60 children in the age group of 6months to 24 months with severe acute malnutrition. Children with severe systemic illnesses were excluded from study. After obtaining informed consent from parents, history focusing on demography, perinatal events, nutrition including breast feeding and immunization status were recorded. Anthropometric parameters were measured. All relevant blood investigations and ultra-sonogram of the chest for thymus size were done. All children were followed up during the course of hospital stay till discharge and were also followed up after 2 months. Relevant blood investigations and ultrasonogram of chest for thymus size were also done during follow up.Results: The difference in means of thymic area by imaging at admission and at discharge (p and lt;0.0001) and at admission and after 8 weeks (p and lt;0.0001) were statistically significant. The increase in weight, length, weight for length, mid upper arm circumference, hemoglobin, total protein, serum albumin, serum globulin from admission to discharge and from discharge to 8 weeks after admission was statistically significant.Conclusions: Thymus size can be used as a marker of immunological dysfunction in severe acute malnutrition and as a marker of severity of the illness. The thymus size was found to be increasing in size during nutritionally rehabilitation and recovery from the illness. Correlations between anthropometric parameters and thymic size are not robust in under-nourished state and during nutritional rehabilitation.

The study aimed at the investigation of neuroprotective activity of macerated ethanolic extract of Indian propolis (MEEP) against β-Amyloid 25–35 (Aβ25-35) induced memory impairment in Alzheimer’s disease. MEEP was administrated orally to Wistar rats at doses of 100, 200 and 300 mg/kg. Behavioral performances were evaluated using morris water maze and radial arm maze. At the end of behavioral study, the brains were removed and antioxidant parameters and brain monoamines were estimated. Further acetylcholinesterase (AchE) inhibition and brain-derived neurotropic factor (BDNF) were evaluated. In addition hematological parameters and histopathological tests were also carried out. In behavioral models, MEEP significantly (P The study concludes that MEEP has anti-Alzheimer potential in rats through multiple mechanisms and further studies are ongoing for fractionation and biological screening.

The study was intended to highlight functional outcome and survival advantage when High Dose Rate (HDR) interstitial implant was used for anterior 2/3rd tongue, either as a primary or as boost depending upon stage of disease. Materials and Methods: Fifty-one patients with squamous cell carcinoma of anterior 2/3rd tongue received interstitial brachytherapy either as primary or as boost with Iridium 192 remote after loading high dose rate (Microselectron or Gamma MediX) machines from November 2008 to September 2013. Age group ranged from 32 to 73 years, mean 52.1. Of these 51, 37 were males and 14 were females. 8 patients belonged to Stage I, 18 from Stage II and 28 patients were Stage III. Stage I patients received primary brachytherapy alone of dose 38.50 Gy to 40 Gy and fraction dose ranged from 250 cGy to 350 cGy. Stage II and Stage III patients received external beam radiation of dose 44 Gy/200cGy per fraction for 22 fractions followed by spinal cord sparing for 6 Gy/200cGy per fraction for 3 fractions. Brachytherapy boost of dose 21 Gy was delivered after external beam radiation. Stage III patients received concurrent chemotherapy with Injection Cisplatin along with external beam radiotherapy 44 Gy/200cGy per fraction for 22 fractions followed by spinal cord sparing for 6 Gy/200cGy per fraction for 3 fractions. Brachytherapy boost of dose 21 Gy was delivered after external beam radiation. 55% of patients were habituated to tobacco and alcohol in one form or the other or both. Surprisingly 45% of patients were nonsmokers and non-alcoholic. Results: Follow-up period ranged from eight months to sixty months. 42 patients had complete response. 9 patients had residual disease. 2 patients died due to non-cancerous cause though they had excellent local control, one with pulmonary tuberculosis and the other with massive Myocardial Infarction. 2 patients died due to disease progression. Overall complete response rate was 82.35%. Those patients who had good coverage index and conformal index had good response compared to those patients with lesser these values. Conclusion: It is surprising to observe from the study that oral cavity cancers are not uncommon in non-smokers and non-alcoholics. Overall complete response of 82% is comparable to any other study quoted in literature. Surgery offers same cure rate but at the rate of organ loss and functional impairment. Organ preservation with good functional outcome is possible in radiotherapy unlike surgery. This study proves brachytherapy can be considered as a surrogate to surgery in early stage tongue cancers with good functional outcome and with lesser morbidity.

The production of refinery sludge has been increasing during tank cleaning, deslugging, and wastewater treatment process. Many efforts have been done to manage the large amount of generated sludge. The gasification of sludge is the most versatile alternative or /and is one potential treatment process for power generation and syngas production. The thermodynamic of gasifier is still not well understood for refinery sludge feedstock. As far as optimising the operational conditions of gasification process is concerned, a successful simulated work is introduced by making use of ASPEN PLUS software simulator. This software was tailored and developed to describe an equilibrium model in updraft gasifier of dry refinery sludge (DRS). The textural characteristic properties of refinery sludge are shown in this paper (ultimate and proximate analysis). In the present study four parameters ( i.e. oxidation zone temperature, operating pressure, air flow rate (l/min) and equivalent ratio) were analyzed. In the present work, details of the equilibrium model are presented. This model shows a better agreement with literature model for biomass gasification. From our model results, the mass fractions yield of the desired products (CO and H2) increases as the oxidation zone temperature increases while their yield decreases after 3 bar. The desired products are found to decrease as the air flow increases while CO2 mass fraction favors high air/fuel ratio. The model results are validated by comparison with experimental data issued from the literature.

Centella asiatica Linn leaves extract are reported to have promising antidepressant activity in acute animal models of depression. The aim of the present study is to evaluate the effects of standardized extract of Centella asiatica L leaves (INDCA) in rats using chronic stress medicated depression model in rats i.e. olfactory bulbectomy model. INDCA was extracted from Centella asiatica L. leaves and standardized to its bioactive constituent, asiaticoside, by HPLC. Effects of 14-day (subacute) oral pretreatment of INDCA (3, 10, or 30 mg/kg), imipramine (20 mg/kg), fluoxetine (30 mg/kg) and desipramine (15 mg/kg) were evaluated after behavioral depression induced by olfactory bulbectomy (OBX) in rats. Separate sham and vehicle control groups were also maintained. Food intake and body weight were measured 1 h prior to treatment (day 1, baseline), and on 7th day and 14th day of treatment. Behavioral and physiological parameters in open field and elevated plus maze were recorded on 14th day of treatment. Dose-dependent reversal of reduction of body weight, body temperature, and heart rate with the normalization of elevated food intake that was observed in OBX rats treated with INDCA. Hyperactivity shown by OBX rats in open field and elevated plus maze paradigm was significantly reversed by INDCA. In conclusion, INDCA exerts antidepressant effects in OBX model in rats.

Objective Barleria lupulina Lindl (Acanthaceae) (B. lupulina) has been traditionally used in the treatment of rheumatoid arthritis but, no scientific data has been published supporting the claimed ethnomedical use. This study was designed to investigate the anti-arthritic potential of B. lupulina leaves and its role in immunomodulation. Methods Methanol extract of B. lupulina (MEBL) leaves (300 and 600 mg/kg BW) was tested for its antiarthritic activity by various models namely, formalin-induced arthritis, adjuvant induced arthritis, collagen type II-induced arthritis and monosodium iodoacetate induced osteoarthritis. Immunomodulatory activity of the same was tested by measuring WBC Count, Spleen Weight, Spleen WBC Count and Delayed Type Hypersensitivity (DTH) Reaction. Results MEBL extracts 300 mg/kg and 600 mg/kg showed statistically significant inhibition (P Conclusions The present study concluded that, MEBL holds antiarthritic and Immunomodulatory activity. Although subsequent study is required to evaluate the active constituents responsible for the activity.

Aim of the study Phyllanthus amarus Schum. and Thonn. (PA) (Euphorbiaceae) is a herb which is reported to have anti-inflammatory activity. In view of its potent anti-inflammatory activity, the present study was designed to evaluate its anti-arthritic activity. Materials and methods The standardized aqueous extract of P. amarus extract (PAE) (2.5% Phyllanthin and hypophyllanthin) was tested against Freund's complete adjuvant (FCA) induced arthritic rats. Arthritis assessment, paw volume, joint diameter, mechanical hyperalgesia and nociceptive threshold were measured. On day 28, the animals were sacrificed, tibiotarsal joint was extracted for histopathology. Results PAE significantly decreased the arthritis which was evident with arthritis index, paw volume and joint diameter. It also significantly increased the mechanical hyperalgesia and nociceptive threshold. The histopathology also revealed the control in inflammation with PAE. Conclusion The present study is suggestive that PAE has prominent anti-arthritic activity which may be attributed to its anti-inflammatory activity.

Produced water is a waste by-product generated during oil and gas recovery operations. It contains the mixture of organic and inorganic compounds. Produced water management is a challenge faced by the petroleum practitioners worldwide. Build-up of chemical wastes from produced water causes huge footprint, which results in high CapEx and OpEx. Different technologies are practiced by various practitioners to treat the produced waste water. However, the constituents removed by each technology and the degree of organic compound removal has to be considered to identify the potential and effective treatment technologies for offshore industrial applications. Current produced water technologies and their successful applications have advantages and disadvantages and can be ranked on the basis of several factors, such as their discharge limit into water bodies, reinjection in producing well, or for any miscellaneous beneficial use. This paper attempts to provide a review of existing physical and chemical treatment technologies used for management of produced water. Based on our analysis, suitable methods will be recommended for offshore waste water treatment technologies.

The main fuel for power generation is combustion of coal and/or natural gas. Natural gas is expensive but clean and less problematic, whereas coal is the reverse of natural gas. Natural gas resources are expected to last until 2020 where else coal has another 200 years expectancy. To replace the natural gas, synthetic gas (syngas) can be used as a substitute fuel. Syngas can be produced using coal as fuel. In this study we blend petcoke, a cheap solid carboneous fuel as an alternative to coal for the production of syngas using a 30 Kwattheat bubbling fluidized bed gasifier. The equivalent ratio (ER) was set at 2.8 and a gasification temperature was maintained between 680 to 710°C by manipulating between the feed flow rates and fluidizing medium. This condition was chosen as it proved to be the optimum based on the work by the same group. Various blend of coal:petcoke between 0 to 100% was analyzed. It was found that a 20:80, petcoke to coal gives a good correlation with 100% coal gasification.

This paper describes the numerical study on the effect of inlet air distribution in the Bubbling Fluidized Bed (BFB) riser of diameter 0.18 m and 1.44 m of length using a 3-hole orifice plate. A 2D model has been developed and meshed using Gambit software version 2.4.6 and was simulated using CFD code, fluent version 6.3. Laminar model has been used for the modeling and Eulerian-Eulerian multiphase model coupled with kinetic theory of granular flow was employed. For the drag, Gidaspow Drag Model was used to calculate the phase interaction between the gas and solid particles. The simulation results obtained for the validation purpose showed good agreement with the results available in the literature. The model with orifice plate gives a better and clear bubble shape with improved turbulent and better mixing compared to the model without the orifice plate. The model with orifice plate is also more realistic and ideal as compared to the model without the orifice plate.

In the present work, details of the equilibrium modeling of dry refinery sludge (DRS) are presented using ASPEN PLUS Simulator in updraft gasifier. Due to lack of available information in the open journal on refinery sludge gasification using updraft gasifier, an evaluate for its optimum conditions on gasification is presented in this paper. For this purpose a Taguchi Orthogonal array design, statistical software is applied to find optimum conditions for DRS gasification. The goal is to identify the most significant process variable in DRS gasification conditions. The process variables include; oxidation zone temperature, equivalent ratio, operating pressure will be simulated and examined. Attention was focused on the effect of optimum operating conditions on the gas composition of H2 and CO (desirable) and CO2 (undesirable) in terms of mass fraction. From our results and finding it can be concluded that the syngas (H2 & CO) yield in term of mass fraction favors high oxidation zone temperature and at atmospheric pressure while CO2 acid gas favor at a high level of equivalent ratio as well as air flow rate favoring towards complete combustion.