HOMOGENEOUS CHARGE COMPRESSION IGNITION COMBUSTION CONTROL BY CNG DIRECT INJECTION

Homogenous Charge Compression Ignition (HCCI) is a combustion process that emits very low nitrogen oxides and has high thermal efficiency. It is one of the few solutions on hand that looks very promising to address the issues on the atmospheric air pollution and depleting fossil fuel resources exacerbated by increasing energy consumption of the world. However, currently there is no established means for HCCI combustion control and it has high HC and CO emissions. In this project, CNG direct injection was proposed as a tool for HCCI combustion control. Proportion of gasoline and CNG flow rates and degree of stratification of CNG were identified as potential parameters for HCCI combustion control. Role of CNG direct injection on HCCI combustion control and corresponding effects on performance and emission characteristics were experimentally investigated. The studies were carried out on a single cylinder, CNG direct injection (CNG DI) research engine. A gasoline fuel injection system and an intake air heater were fitted to the engine to operate the engine with dual fuels and in HCCI mode. Compression ignition combustion of homogeneously premixed charge of gasoline was achieved by heating the intake air and CNG was directly injected. CNG stratification was achieved by direct injection on a specially designed piston with a groove on its crown. The degree of stratification was varied by changing the start of CNG injection. Early injection (300° BTDC) created homogeneous mixtures and stratified mixtures were obtained by retarding the injection timing. High degrees of stratification were obtained by injecting at 80° and 120° BTDC, that is, after the closure of intake valves (132° BTDC). To study the effect of fuel proportions, CNG injection rate was varied at constant equivalence ratio of gasoline (φg) at 0.20 to 0.26. The effects of CNG stratification were studied by changing the injection timing form 300° to 80° BTDC and all experiments were repeated at different engine speeds ranging from 1200 to 2100 rpm. It was observed that heat released by gasoline HCCI combustion resulted in the subsequent combustion of CNG and the engine load could be increased by varying the CNG injection rate. Proportions of gasoline and CNG and degree of stratification of CNG were found to be effective means of combustion control within certain limits of engine load and HC and CO emissions could be significantly reduced

Synthesis and Characterization of CoO-ZnO-Based Nanocomposites for Gas-Sensing Applications

CoO-ZnO composite nanofibers were synthesized through electrospinning technique. CoO-ZnO composite nanofibers were fabricated by doping zinc (zinc acetate dihydrate) and varied concentrations of cobalt (cobalt oxide) in the ratio of 1, 3, and 5 wt%, respectively. By modifying the solvent and the electrospinning parameters, different tests were carried out to optimize the morphological properties of the synthesized composite nanofibers. The morphological characterization was performed by scanning electron microscopy (SEM) with a field emission gun. The atomic composition of the nanofibers was analyzed by energy-dispersive X-ray (EDX) spectroscopy using a solid-state detector. Gas-sensing performances are done at different temperatures like at room temp, 50°C, and 100°C to find out the optimum operating temperature for detecting acetone gas. The sensitivity studies of CoO-ZnO composite nanofiber were carried out over different concentrations of acetone gas from 50 to 250 ppm. The sensitivity of this sensor developed is found to be increasing with increase in temperature and also increases if dopant concentration increases when compared with pure nanofibers. The sensitivity analysis proved a fact that uncalcinated CoO-ZnO composite nanofibers can be helpful in the detection of diabetics at the early stage with acetone concentration in the breaths

COVID-19 challenges in clinical trials

Clinical research involves working with human subjects to answer questions relevant to their well-being in an ethical manner. The current scenario from the past one year has drastically changed the face of the clinical trials. The present COVID prevalence and simultaneously conducting the research with all the regulations and the precautions has been the difficult task for the contract research organisations (CRO)

Randomized, single-dose, two-period, two-sequence crossover bioequivalence study evaluating two oral formulations of lamotrigine in healthy volunteers

Background: Lamotrigine is an anti-epileptic medicine used to treat epilepsy and bipolar disorder. The mechanism of action is to block voltage activated sodium channels. The aim of this study was to evaluate the bioequivalence of 2 oral formulations of lamotrigine 25 mg in healthy volunteers.Methods: A single-dose, two-period, randomized crossover study design in - healthy Indian adult volunteers was conducted at Amaris Clinical, a division of Caplin Point Laboratories Ltd., Chennai. A validated high performance liquid chromatography in conjunction with mass spectrometry was used. Lamotrigine concentration in plasma. Adverse events were determined by measuring vital functions after dosing. A total of 24 subjects were included.Results: The mean and 90% confidence intervals of the test / reference ratios for these parameters were as follows: The mean Cmax and Tmax of the test were 758.606 (157.453) ng / ml and 1.17 (0.50-5.00) hours, respectively. The mean Cmax and Tmax of the reference were 775.993 (151.654) ng / ml or 0.88 (0.25-4.00) hours. The mean AUC0-72 was 24142. 031±3641.691 (ng.hr/mL) for the test formulation and 24202.099±3742.957 (ng. h / ml) for the reference formulation. The mean test / reference ratios for Cmax and AUC0-72 were 97.92 and 99.82 respectively. The 90% parametric CIs for Cmax and AUC0-72 were 90.17-105.68% or 97.87-101.81%.Conclusions: The 90% confidence intervals ranged from 80-125% and it was concluded that the test product was bioequivalent to the reference product in these healthy adult male volunteers.

Biomarkers in ROS and Role of Isoprostanes in Oxidative Stress

Biomarkers of reactive oxygen species serve as indicators of oxidative stress in the pathology of cardiovascular diseases. This chapter presents an overview of the various biomarkers available to quantify oxidative stress to advance the understanding of the pathophysiology of cardiovascular diseases as well as to serve as an adjunct in their diagnosis and prognosis. The plasma levels of reactive oxygen species themselves are unstable and unreliable markers of oxidative stress. The commonly used stable biomarkers are derivatives of oxygen radicals such as products of lipid peroxidation and protein oxidation, with isoprostanes and malondialdehyde (MDA) being the most widely used biomarkers due to higher specificity and ease of measurement. Recently, micro‐RNA is emerging as stable and specific biomarkers for detection of heart failure. Other biomarkers have a role in certain conditions; for example, advanced oxidation protein products indicate acute inflammation, whereas advanced glycation end products serve as indicators of chronic disease

HOMOGENEOUS CHARGE COMPRESSION IGNITION COMBUSTION CONTROL BY CNG DIRECT INJECTION

Homogenous Charge Compression Ignition (HCCI) is a combustion process that emits very low nitrogen oxides and has high thermal efficiency. It is one of the few solutions on hand that looks very promising to address the issues on the atmospheric air pollution and depleting fossil fuel resources exacerbated by increasing energy consumption of the world. However, currently there is no established means for HCCI combustion control and it has high HC and CO emissions. In this project, CNG direct injection was proposed as a tool for HCCI combustion control. Proportion of gasoline and CNG flow rates and degree of stratification of CNG were identified as potential parameters for HCCI combustion control. Role of CNG direct injection on HCCI combustion control and corresponding effects on performance and emission characteristics were experimentally investigated. The studies were carried out on a single cylinder, CNG direct injection (CNG DI) research engine. A gasoline fuel injection system and an intake air heater were fitted to the engine to operate the engine with dual fuels and in HCCI mode. Compression ignition combustion of homogeneously premixed charge of gasoline was achieved by heating the intake air and CNG was directly injected. CNG stratification was achieved by direct injection on a specially designed piston with a groove on its crown. The degree of stratification was varied by changing the start of CNG injection. Early injection (300° BTDC) created homogeneous mixtures and stratified mixtures were obtained by retarding the injection timing. High degrees of stratification were obtained by injecting at 80° and 120° BTDC, that is, after the closure of intake valves (132° BTDC). To study the effect of fuel proportions, CNG injection rate was varied at constant equivalence ratio of gasoline (φg) at 0.20 to 0.26. The effects of CNG stratification were studied by changing the injection timing form 300° to 80° BTDC and all experiments were repeated at different engine speeds ranging from 1200 to 2100 rpm. It was observed that heat released by gasoline HCCI combustion resulted in the subsequent combustion of CNG and the engine load could be increased by varying the CNG injection rate. Proportions of gasoline and CNG and degree of stratification of CNG were found to be effective means of combustion control within certain limits of engine load and HC and CO emissions could be significantly reduced

(4-Bromo­phen­yl)(1-phenyl­sulfonyl-1H-indol-2-yl)methanone

In the title compound, C21H14BrNO3S, the indole ring system forms dihedral angles of 65.64 (8) and 59.30 (8)°, respectively, with the phenyl and bromo­phenyl rings. In the crystal, mol­ecules are connected by a C—H⋯O hydrogen bond, forming a chain along [101]. The chains are further connected by weak inter­molecular C—H⋯π inter­actions, forming a layer parallel to the ac plane

1,3-Dimethyl-5-(2-methyl­benzyl­idene)pyrimidine-2,4,6(1H,3H,5H)-trione

In the title compound, C14H14N2O3, the dihedral angle between the pyrimidine and benzene rings is 14.9 (1)°. The mol­ecular structure is stabilized by weak intra­molecular C—H⋯O inter­actions and the crystal structure exhibits a weak inter­molecular π–π inter­action [centroid–centroid distance = 3.575 (3) Å]

Knowledge of Risk Factors, Symptoms and Barriers to Seeking Medical Help for Cervical Cancer among Omani Women Attending Sultan Qaboos University Hospital

Objectives: This study aimed to assess knowledge and attitudes among Omani woman regarding cervical cancer risk factors and symptoms as well as barriers to them seeking medical help. Methods: This cross-sectional study was conducted between December 2017 and March 2018 at the Sultan Qaboos University Hospital (SQUH) in Muscat, Oman. A validated Arabic-language version of the Cervical Cancer Awareness Measure questionnaire was used to collect data from 550 Omani women visiting SQUH during the study period. Results: A total of 490 women participated (response rate: 89.1%) in this study. Overall, the women demonstrated low levels of knowledge of cervical cancer risk factors and symptoms (28.5% and 45.0%, respectively). The most frequently recognised risk factor was having many children (36.1%), while the most recognised symptom was unexplained vaginal bleeding (69.8%). Women reported that being too scared was the greatest barrier to seeking medical help (68.0%). Various factors were significantly associated with greater knowledge of cervical cancer signs and symptoms including education level (odds ratio [OR] = 2.85; 95% confidence interval [CI]: 1.0–8.22; P <0.05), income (OR = 4.34; 95% CI: 1.70–11.12; P <0.05), parity (OR = 3.59; 95% CI: 1.38–9.36; P <0.05) and a family history of cancer (OR = 1.71; CI: 1.0–2.90; P <0.05). Conclusion: Overall, Omani women demonstrated poor knowledge with regards to cervical cancer; in addition, they identified several emotional barriers to seeking medical help. Healthcare practitioners should reassure female patients to encourage care-seeking behaviour. A national screening programme is also recommended to increase awareness and early diagnosis of cervical cancer in Oman.Keywords: Cervical Cancer; Knowledge; Awareness; Risk Factors; Health Care Seeking Behavior; Women; Oman

PPAR γ

Peroxisome proliferator-activated receptor Gamma (PPARγ), a ligand-activated transcription factor, has a role in various cellular functions as well as glucose homeostasis, lipid metabolism, and prevention of oxidative stress. The activators of PPARγ are already widely used in the treatment of diabetes mellitus. The cardioprotective effect of PPARγ activation has been studied extensively over the years making them potential therapeutic targets in diseases associated with cardiovascular disorders. However, they are also associated with adverse cardiovascular events such as congestive heart failure and myocardial infarction. This review aims to discuss the role of PPARγ in the various cardiovascular diseases and summarize the current knowledge on PPARγ agonists from multiple clinical trials. Finally, we also review the new PPARγ agonists under development as potential therapeutics with reduced or no adverse effects