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Aims: Acetyl-coA Carboxylase 1 (ACC1) is an enzyme that couples glucose metabolism with de novo lipid synthesis in lipogenic tissues, by converting acetyl-CoA to malonyl-CoA. In beta cells, ACC1 plays a critical role in beta cell growth and insulin secretion . However, very little is known about how ACC1 activity is regulated in beta cells. The aims of the current project were to 1) assess the role of the AMP-activated protein kinase phospho-site serine 79 (ACC1S79) in beta cell function and whole body glucose homeostasis; and 2) screen for novel phospho-sites that may regulate ACC1 activity in beta cells. Methods: (i) To investigate the functional role of the ACC1S79 phospho-site in beta cell function, we studied a mouse model with ACC1S79 mutated to alanine (ACC1S79A), which were obtained by crossing ACC1 double knock-in mice 2 with wild type mice to isolate the ACC1S79A point mutation. We assessed glucose homeostasis in vivo and insulin secretion from primary islets. (ii) We purified the ACC1 protein from transformed INS1 beta cells following culture with different glucose concentrations, and performed quantitative unbiased phosphoproteomics to characterise ACC1 phospho-sites. Mass spectrometry (LC-MS/MS) was performed using a Q- Exactive MS, mascot searches run against the Uniprot data base, and data analysed using MaxQuant and Perseus. We generated phospho-specific antibodies against key phospho-sites identified that exhibited a dynamic response to glucose stimulation, and used western blotting to investigate these sites further. Results: (i) Female ACC1S79A mice exhibited normal glucose homeostasis, whilst males showed lower fasting blood glucose, and a modest reduction in blood glucose during glucose and insulin tolerance tests compared to wild type littermate controls. No significant differences in fasted or glucose-stimulated serum insulin levels were found between the genotypes in vivo. Likewise, there was no significant change in insulin secretion from isolated ACC1S79A islets at baseline (2 mmol/l glucose) or in response to glucose-stimulation (7.5 and 20 mmol/l glucose). (ii) Using quantitative phosphoproteomics, we identified twenty phospho-sites on the ACC1 protein in beta cells. ACC1S1215 was highly-phosphorylated at 2 mmol/l glucose, and showed a marked and highly significant reduction in phosphorylation in response to 15 mmol/l glucose, in contrast to the more modest changes in phosphorylation of ACC1S79. In contrast, phosphorylation of ACC1S25 and ACC1S49 was lower at basal glucose and increased upon glucose stimulation. Validation by western blotting confirmed that ACC1S1215 phosphorylation was highly-regulated by glucose, with ACC1S79 phosphorylation more subtle. Conclusions: Our data demonstrate that phosphorylation of ACC1S79 does not play a major role in insulin secretion in vivo or ex vivo. However, other phospho-sites identified by our phosphoproteomic screen may play a role in regulating ACC1 activity in beta cell and other ACC1-expressing tissues.

Vehicle efficiency relates to pollutants and cost savings in third world countries. In term of subcompact cars, the vehicle characteristics are governed by the engine and road load characteristics. Overall, it involves the rolling resistance and aerodynamics loading on the moving car on the road. Tests were conducted on a local subcompact car to measure engine speed, throttle position and air fuel ratio while Global Positioning Systems (GPS) recorded data of the vehicle speed and position. Also, dynamometer testing was done to reflect the vehicle characteristics. The results of on the road roll down test and cruising test were combined to get the road load characteristics of the vehicle. A comparison of the road loads obtained with actual engine dynamometer test was found to have about 5% error. The errors of the experiments shows the validation of the tests.

A comprehensive computer model (EFLP) has been developed for carrying out friction estimation and analysis of sparks ignited in reciprocating engines. EFLP considers five major loss components in an automotive engine: the crankshaft, piston, valvetrain, auxiliary components and pumping losses. Hydrodynamic, mixed, and boundary layer regimes are used to model the friction phenomena. The main building blocks of EFLP are empirical engine friction models based on experimental data. EFLP is constructed using MATAB-based engine code for estimating engine performance. The friction in a 4-cylinder 4-stroke engine is inspected. The results predicted by EFLP were validated according to a case study available in the literature. The validation showed that EFLP predictions are realistic and accurate.

The solar radiation study have been undertaken at Pekan campus (3.5oN, 103.4oE), Faculty of Mechanical Engineering, University Malaysia Pahang to utilize solar energy in east coast of Malaysia. The knowledge of the daily variation of global solar radiation is a necessity at the particular locality to consider the feasibility of solar energy utilisation. Hence, the diurnal patterns of global solar radiation were obtained using measured data from weather station which was installed at the site for three years (2011 – 2013). The patterns have been divided into five conditions such as clear sky, partially cloudy, fully cloudy, afternoon rain, and northeast monsoon season day. It was observed that on a clear sky day in Pekan, the maximum solar insolation was 939 W/m 2 and total solar energy received was 6.51 kWhr/m 2 . In contrast, on a fully cloudy day the maximum solar insolation was only 30 W/m 2 and total solar energy received was 0.35 kWhr/m 2 . Besides that, the empirical models were developed to estimate the monthly average daily global solar radiation on a horizontal surface with Pekan meteorological station data. Subsequently, the models were evaluated using statistical analysis. Based on analysis results, Eq. (13) and Eq. (15) models are proposed to estimate monthly average daily global solar radiation for Pekan. The present paper describes on advance understanding of daily variation global solar radiation in east coast Malaysia whereby it has significance for designing a solar system. Lastly, the developed Angstrom’s modified linear models are highly recommended to be used to estimate the monthly average daily global solar radiation in Pekan, Pahang and location with similar solar radiation patterns in east coast Malaysia.

Solid particles dispersed in a liquid with sizes no larger than 100nm, known as nanofluids, are used to enhance Thermophysical properties compared to the base fluid. Preparations of alumina (Al2O3), titania (TiO2) and silica (SiO2) in water have been experimentally conducted in volume concentrations ranging between 1 and 2.5%. Thermal conductivity is measured by the hot wire method and viscosity with viscometer equipment. The results of thermal conductivity and viscosity showed an enhancement (0.5–20% and 0.5–60% respectively) compared with the base fluid. The data measured agreed with experimental data of other researchers with deviation of less than 5%. The study showed that alumina has the highest thermal conductivity, followed silica and titania, on the other hand silica has the highest viscosity followed alumina and titania.

This paper presents a review of the studies undertaken on convection heat transfer with nanofluids. Initial studies were directed towards the determination of the properties of nanofluids, especially their thermal conductivity and viscosity. The studies indicate that thermal conductivity and viscosity increase with an increase in the concentration of the nanofluid. Experiments were conducted with different nanofluids, at various concentrations and temperature ranges, for the estimation of the heat transfer coefficient and friction factor for water-based nanofluids. All the studies confirmed enhancement of the heat transfer coefficient with an increase in concentration. The experimental ranges of temperature undertaken by the authors were different for different nanofluids. Certain studies with smaller particle sizes indicated an increase in heat transfer enhancements when compared with values obtained when using larger particle sizes. It is observed that the concentration of the nanofluid, the operating temperature, the particle size and shape, together with the material of the nanoparticle dispersed in the base liquid, have significant influence on the heat transfer coefficient. All the studies indicate a nominal increase in pressure drop.

Solid particles dispersed in a liquid with sizes no larger than 100nm, known as nanofluids, are used to enhance Thermophysical properties compared to the base fluid. Preparations of alumina (Al2O3), titania (TiO2) and silica (SiO2) in water have been experimentally conducted in volume concentrations ranging between 1 and 2.5%. Thermal conductivity is measured by the hot wire method and viscosity with viscometer equipment. The results of thermal conductivity and viscosity showed an enhancement (0.5–20% and 0.5–60% respectively) compared with the base fluid. The data measured agreed with experimental data of other researchers with deviation of less than 5%. The study showed that alumina has the highest thermal conductivity, followed silica and titania, on the other hand silica has the highest viscosity followed alumina and titania.

Hydrogen induction strategy in an internal combustion engine plays a vital role in increasing the power density and prohibiting combustion anomalies. This paper inspects the performance characteristics of cylinder hydrogen-fueled engine with port injection feeding strategy. To that end, a one-dimensional gas dynamic model has been built to represent the flow and heat transfer in the components of the engine. The governing equations are introduced followed by the performance parameters and model description. Air-fuel ratio was varied from a stoichiometric limit to a lean limit. The rotational speed of the engine was also changed from 1000 to 4500 RPM. The injector location was fixed in the mid-point of the intake port. The general behavior of the hydrogen engine was similar to that of a gasoline engine, apart from a reduction in the power density, which was due to a decrease in the volumetric efficiency. This emphasizes the ability of retrofitting traditional engines for hydrogen fuel with minor modifications. The decrease in the volumetric efficiency needs to be rectified.

This paper presents a finite element analysis of the stress distribution in the end milling operation of nickel-based superalloy HASTELLOY C-2000. Commercially available finite element software was used to develop the model and analyze the distribution of stress components in the machined surface of HASTELLOY C-22HS following end milling with coated carbide tools. The friction interaction along the tool-chip interface was modeled using the Coulomb friction law. It was found that the stress had lower values under the cut surface and that it increased gradually near the cutting edge.

Objective: To evaluate copper and zinc concentrations in plasma and follicular fluid from cattle ovaries, and estimate the impact of rational concentrations of copper and zinc oxide nanoparticles (CuO-NPs & ZnO-NPs) supplemented during in vitro maturation (IVM) against DNA damage of cumulus cells, glutathione content in oocytes and on consequent embryo development. Methods: Oocytes were obtained from 2 to 8 mm follicles by aspiration method for IVM. Replicates of experiments were performed on different days, with a separate batch of cumulus oocytes complex for each day. Results: The DNA damage of oocytes and cumulus cells significantly decreased with supplemental CuO-NPs or ZnO-NPs concentrations of 0.7 and 1.0 μg/mL in the IVM medium compared to medium without CuO-NPs or ZnO-NPs (P < 0.01). Total glutathione concentrations in oocytes and cumulus cells significantly increased following supplementation with both 0.7 and 1.0 μg/mL CuO-NPs or ZnO-NPs in comparison with 0 and 0.4 μg/mL CuO-NPs or ZnO-NPs supplemented groups (P < 0.01). Supplementation of CuO-NPs or ZnO-NPs during IVM medium at any concentration had no significant effect on cleavge rate. Both CuO-NPs and ZnO-NPs significantly increased blastocyst rates when oocytes were matured with 0.7, 1.0 μg/mL CuO-NPs concentrations (P < 0.01). In contrast, addition of 1.5 μg/mL of CuO-NPs or ZnO-NPs to the maturation media resulted in detrimental effects on the developmental competence of bovine oocytes confirming toxicity induced by CuO-NPs and ZnO-NPs in high concentrations. Conclusions: CuO-NPs or ZnO-NPs-treated bovine oocytes during IVM show low level of DNA fragmentation and increased intracellular glutathione content of cumulus cells. In vitro embryo development is improved by supplementation of rational concentrations of CuO-NPs or ZnO-NPs to culture media. Toxicity induced by CuO-NPs and ZnO-NPs is confirmed in high concentrations.