Influence of oxyhydrogen gas retrofit into two-stroke engine on emissions and exhaust gas temperature variations.

The generation of power and fuel sustainability that contributes to a cleaner output of exhaust gases is one of the most important objectives the world seeks. In this paper, oxyhydrogen gas is used to retrofit into a two-stroke engine. The water was electrolysed and generated a mixture of oxygen (O2) and hydrogen (H2) or known as oxyhydrogen (HHO) gas via an electrolytic dry cell generator. The HHO was retrofitted experimentally to investigate the engine emissions and exhaust gas temperature from a 1.5 kW gasoline engine. The engine was tested with different power ratings (84-720 W) to investigate the performance and emissions of the engine using gasoline followed by the addition of HHO. The emissions of CO and NOx were measured with different amounts of HHO added. The exhaust temperature was calculated as one of the variables to be considered in relation to pollution. The air-fuel ratios are varied from 12 to 20% in the experiment. The most appropriate air-fuel ratio needed to start the generator with the most environmentally friendly gas emission was analysed. The results showed that the addition of HHO to the engine is successful in reducing fuel consumption up to 8.9%. A higher percentage of HHO added also has improved the emissions and reduced exhaust gas temperature. In this study, the highest quantity of HHO added at 0.15% of the volume fraction reduced CO gas emission by up to 9.41%, NOx gas up to 4.31%, and exhaust gas temperature by up to 2.02%. Generally, adding oxyhydrogen gas has significantly reduced the emissions, and exhaust temperature and provided an eco-friendly environment.

Optimization of subcritical water pre-treatment for biogas enhancement on co-digestion of pineapple waste and cow dung using the response surface methodology.

The optimal pre-treatment method and conditions depend on the types of lignocellulose present due to the complexity and the variability of biomass chemical structures. This study optimized subcritical water pre-treatment to ensure maximum methane production from pineapple waste prior to anaerobic co-digestion with cow dung using the response surface methodology. A central composite design was achieved with three different factors and one response. A total of 20 pre-treatment runs were performed at different temperatures, reaction times and water to solid ratios suggesting optimum values for subcritical water pre-treatment at 128.52℃ for 5 min with 5.67 to 1 water to solid ratio. Under these conditions, methane yield increased from 59.09 to 85.05 mL CH4/g VS with an increase of 23% biogas yield and 44% methane yield from the untreated. All pre-treatments above 200℃ showed reductions in biogas yield. Compositional analysis showed slight reduction of lignin and increase in α-cellulose content after the pre-treatment. Analysis using Fourier transform infrared spectroscopy and thermogravimetric analysis verified the presence of cellulosic material in pre-treated pineapple waste. Most of the hemicellulose was solubilized in the liquid samples after SCW pre-treatment. The crystallinity index of pineapple waste was reduced from 57.58% (untreated) to 54.29% (pre-treated). Scanning electron microscopy confirmed the structural modification of pre-treated pineapple waste for better microbial attack. Subcritical water pre-treatment is feasible as a promising method to enhance the anaerobic co-digestion process. Further study should be conducted to assess the scale-up of the process from pre-treatment to anaerobic digestion at the pilot plant level.

Evaluation of vascular endothelial growth factor (VEGF) level in the tears and serum of age-related macular degeneration patients.

Age-related macular degeneration (AMD) is an important cause of irreversible central blindness worldwide. Clinical manifestations range from asymptomatic in early and intermediate AMD to significant vision loss in late AMD. Approximately 10% of cases of early AMD eventually progress to the late advanced stage, influenced by the upregulation of vascular endothelial growth factor (VEGF). In this study, we evaluated VEGF concentration in the tears and serum of AMD patients. Our study revealed a significantly higher level of VEGF in the tears of patients with AMD compared with controls. The tear VEGF level has high sensitivity and specificity, and is significantly related to the severity of AMD, whilst serum VEGF level is non-specific and non-predictive of AMD severity. Thus, VEGF level in the tears may be used as a non-invasive biomarker for AMD progression. A large cohort study is needed for further verification.

Cell viability and electrical response of breast cancer cell treated in aqueous graphene oxide solution deposition on interdigitated electrode.

Breast cancer is one of the most reported cancers that can lead to death. Despite the advances in diagnosis and treatment procedures, the possibility of cancer recurrences is still high in many cases. With that in consideration, researchers from all over the world are showing interest in the unique features of Graphene oxide (GO), such as its excellent and versatile physicochemical properties, to explore further its potential and benefits towards breast cancer cell treatment. In this study, the cell viability and electrical response of GO, in terms of resistivity and impedance towards the breast cancer cells (MCF7) and normal breast cells (MCF10a), were investigated by varying the pH and concentration of GO. Firstly, the numbers of MCF7 and MCF10a were measured after being treated with GO for 24 and 48 h. Next, the electrical responses of these cells were evaluated by using interdigitated gold electrodes (IDEs) that are connected to an LCR meter. Based on the results obtained, as the pH of GO increased from pH 5 to pH 7, the number of viable MCF7 cells decreased while the number of viable MCF10a slightly increased after the incubation period of 48 h. Similarly, the MCF7 also experienced higher cytotoxicity effects when treated with GO concentrations of more than 25 µg/mL. The findings from the electrical characterization of the cells observed that the number of viable cells has corresponded to the impedance of the cells. The electrical impedance of MCF7 decreased as the number of highly insulating viable cell membranes decreased. But in contrast, the electrical impedance of MCF10a increased as the number of highly insulating viable cell membranes increased. Hence, it can be deduced that the GO with higher pH and concentration influence the MCF7 cancer cell line and MCF10a normal breast cell.

Entropy Generation and Exergy Analysis of Premixed Fuel-Air Combustion in Micro Porous Media Burner.

The performance of porous media micro-burners plays an important role in determining thermal efficiency and improving our daily life. Nowadays, a lot of scholars are actively involved in this research area and ongoing studies are still being carried out due to the burners' excellent performance. The exergy efficiency and entropy generation of a porous media burner are strongly dependent on the characteristics of the flame and its thermal behavior. In this study, a single-layer and double-layer porous media form were constructed to investigate the effects of various types of porous foam arrangement in a cylindrical burner. The burner was operated using premixed butane-air combustion with an inner diameter of 23 mm and a length of 100 mm. The experiments were carried out in rich fuel conditions with an equivalence ratio, φ ranging from 1.3 to 2.0. The results showed significant improvement in the thermal and exergy efficiency with an increase in the equivalence ratio in a double-layer compared with a single-layer. The peak temperature recorded was 945.21 °C at φ = 1.3 for a porcelain single-layer, and the highest exergy efficiency was 83.47% at φ = 2.0 for an alumina-porcelain double-layer burner. It was also found that the average temperature of the burner wall decreased with an increase in the equivalence ratios for PMB2 and PMB4, whereas the average wall temperature for PMB3 was largely unaffected by the equivalence ratios. The total entropy generation rate reached the highest value at φ = 2.0 for all PMB configurations, and the highest percentage increase for total entropy generation rate was 46.09% for PMB1. The exergy efficiency for all burners was approximately similar with the highest exergy efficiency achieved by PMB4 (17.65%). In addition, the length and location of the flame with thermal distribution was significantly affected by the equivalence ratio between the single-layer and double-layer porous material. Overall, a double-layer porous media burner showed the best performance calculated based on the second law of thermodynamics when compared with other configurations, and it is ideal for domestic application.

Genetic analysis and identification of SSR markers associated with rice blast disease in a BC2F1 backcross population.

Rice (Oryza sativa L.) blast disease is one of the most destructive rice diseases in the world. The fungal pathogen, Magnaporthe oryzae, is the causal agent of rice blast disease. Development of resistant cultivars is the most preferred method to achieve sustainable rice production. However, the effectiveness of resistant cultivars is hindered by the genetic plasticity of the pathogen genome. Therefore, information on genetic resistance and virulence stability are vital to increase our understanding of the molecular basis of blast disease resistance. The present study set out to elucidate the resistance pattern and identify potential simple sequence repeat markers linked with rice blast disease. A backcross population (BC2F1), derived from crossing MR264 and Pongsu Seribu 2 (PS2), was developed using marker-assisted backcross breeding. Twelve microsatellite markers carrying the blast resistance gene clearly demonstrated a polymorphic pattern between both parental lines. Among these, two markers, RM206 and RM5961, located on chromosome 11 exhibited the expected 1:1 testcross ratio in the BC2F1 population. The 195 BC2F1 plants inoculated against M. oryzae pathotype P7.2 showed a significantly different distribution in the backcrossed generation and followed Mendelian segregation based on a single-gene model. This indicates that blast resistance in PS2 is governed by a single dominant gene, which is linked to RM206 and RM5961 on chromosome 11. The findings presented in this study could be useful for future blast resistance studies in rice breeding programs.

Morphological phylogenetic analysis of seven varieties of Ficus deltoidea Jack from the Malay Peninsula of Malaysia.

This study is the first report to suggest a morphological phylogenetic framework for the seven varieties of Ficus deltoidea Jack (Ficus: Moraceae) from the Malay Peninsula of Malaysia. Several molecular-based classifications on the genus Ficus had been proposed, but neither had discussed the relationship between seven varieties of F. deltoidea to its allies nor within the varieties. The relationship between seven varieties of F. deltoidea is still debated due to the extreme morphological variabilities and ambiguous boundaries between taxa. Thus, the correct identification of these varieties is important as several morphological characters are variety-specific. To test the monophyly and further resolved the relationship in F. deltoidea, a morphological phylogenetic analysis was conducted based on herbarium specimens representing the seven varieties of F. deltoidea that were collected from the Malay Peninsula of Malaysia, by using related species of the genus Ficus; F. grossularioides, F. ischnopoda and F. oleifolia as the outgroups. Parsimony and neighbour-joining analyses indicated that F. deltoidea is monophyletic, in that the seven varieties of F. deltoidea nested into two clades; clade subspecies deltoidea (var. deltoidea, var. bilobata, var. angustifolia, var. kunstleri and var. trengganuensis) and clade subspecies motleyana (var. intermedia and var. motleyana).

Nutritional status and health-related quality of life of breast cancer patients on chemotherapy.

INTRODUCTION: Nutritional decline is typically accepted as a consequent of the course of treatment for cancer. This study aimed to (1) assess body weight status and dietary intake of breast cancer patients on chemotherapy and (2) to correlate Body Mass Index (BMI), energy and protein intake with health-related quality of life (HRQoL) profile. METHODS: A cross-sectional study was conducted in two government hospitals in the East coast of Peninsular Malaysia using convenience sampling. Women aged > or =18 years, who were diagnosed with breast cancer and receiving chemotherapy were invited to participate. The following aspects were evaluated: body weight status, usual dietary intake (diet history) and HRQoL (EORTC QLQ-C30). Descriptive statistics and non-parametric tests were employed (SPSS 16). RESULTS: Of the respondents, 41 were 49 +/- 9.6 years of age; 92.7% were Malay; 97.6% (response rate = 91%) were on moderately emetogenic chemotherapy. Over half of the patients were overweight or obese (mean BMI = 25.3 +/- 1.1 kg/m2). The majority self-reported weight reduction (46.3%) but positive energy balance was detected with the current energy and protein intakes recorded at 1792.6 +/- 304.9 kcal/day (range= 1200-2500) and 74.5 g/day (IqR= 37.7) respectively. Dietary intakes were, however, not correlated with HRQoL, but greater BMI was associated with better emotional and cognitive functioning and less fatigue. CONCLUSION: Although most patients declared losing weight, obesity and excess dietary intake were noted. Additionally, body weight status has been shown to be important in HRQoL profile, underlining the necessity for effective nutritional assessments and support to the cancer population.

Nutritional Status and Health-Related Quality of Life of Breast Cancer Patients on Chemotherapy

Introduction: Nutritional decline is typically accepted as a consequent of the course of treatment for cancer. This study aimed to (1) assess body weight status and dietary intake of breast cancer patients on chemotherapy and (2) to correlate Body Mass Index (BMI), energy and protein intake with health-related quality of life (HRQoL) profile. Methods: A cross-sectional study was conducted in two government hospitals in the East coast of Peninsular Malaysia using convenience sampling. Women aged >18 years, who were diagnosed with breast cancer and receiving chemotherapy were invited to participate. The following aspects were evaluated: body weight status, usual dietary intake (diet history) and HRQoL (EORTC QLQ-C30). Descriptive statistics and non-parametric tests were employed (SPSS 16). Results: Of the respondents, 41 were 49 ± 9.6 years of age; 92.7% were Malay; 97.6% (response rate = 91%) were on moderately emetogenic chemotherapy. Over half of the patients were overweight or obese (mean BMI = 25.3 ± 1.1 kg/m2). The majority self-reported weight reduction (46.3%) but positive energy balance was detected with the current energy and protein intakes recorded at 1792.6 ± 304.9kcal/day (range= 1200-2500) and 74.5g/day (IqR= 37.7) respectively. Dietary intakes were, however, not correlated with HRQoL, but greater BMI was associated with better emotional and cognitive functioning and less fatigue. Conclusion: Although most patients declared losing weight, obesity and excess dietary intake were noted. Additionally, body weight status has been shown to be important in HRQoL profile, underlining the necessity for effective nutritional assessments and support to the cancer population.

Energy density and weight of food effect short-term caloric compensation in men.

OBJECTIVE: The purpose of the study was to examine the effect of energy density and food weight (volume) on subsequent intake. DESIGN: Sixteen lean men were each studied four times during a 2-d protocol at the Rowett's Human Nutrition Unit. On day 1, subjects were fed a mandatory diet at 1.6 x resting metabolic rate (RMR). On day 2, during the mandatory morning period (08.30-12.30) subjects consumed a fixed breakfast (08.30) plus a snack (10.30) in one of four treatments [with values in weight (kg), ED (kJ/100g), Energy (MJ)]: (i) zero intake, 0:0:0 (ii) low energy density (LED), 0.615: 400: 2.46; (iii) high energy density (HED), 0.615: 800: 4.92; (iv) 2 x LED, 1.225: 400: 4.91. From 12.30, throughout the remainder of the day, subjects had ad libitum access to 15 high-protein, 15 high-fat and 15 high-carbohydrate foods. Motivation to eat was tracked hourly using 100 mm line scales. RESULTS: ANOVA showed subjects were hungrier after the zero and LED treatments in the mandatory period (p<0.001). Lunch time EI was 5.0, 3.1, 4.2 and 3.2 MJ on the zero, HED, LED and 2 x LED treatments, respectively (p<0.001). Total ad libitum EI was 11.7, 9.6, 10.3 and 9.5 MJ/d, respectively (p=0.033). Total ad libitum plus mandatory intakes amounted to 11.7, 14.5, 12.6 and 14.4 MJ/d, respectively (p=0.001). Corresponding food intakes were 2.18, 2.39, 2.51 and 3.06 kg/d, respectively (p<0.001). CONCLUSIONS: The present study showed that subjects respond to both the amount of food eaten in the morning and to the energy density of those foods. However, compensation was only partial and short-term. Subjects only compensated EI by approximately 40% and that compensation only occurred at the next meal.

Carbohydrates, appetite and feeding behavior in humans.

The view of carbohydrates in relation to obesity has changed over the past few decades from being conducive to overconsumption and weight gain to being protective. This article reviews the mechanisms by which carbohydrate is purported to protect against weight gain. Although carbohydrate is metabolized and stored in the body less efficiently than fat, when de novo lipogenesis is invoked on very high carbohydrate diets, the beneficial effect on energy balance is likely to be minimal when typical high fat Western diets are consumed. However, it has been suggested that high carbohydrate foods may influence energy balance by reducing food intake through greater satiety effects, reducing energy density and displacing fat from the diet-the fat-sugar seesaw effect. To date, there seem to be few differences between sugars and starches on satiety and energy intake, but few studies have examined this. Some reduced-fat, and, therefore, higher carbohydrate, foods are highly energy dense. High carbohydrate foods do not necessarily have a low energy density. Evidence from recent studies suggests that adding carbohydrate, and especially sugar, to the diet neither displaces fat from the diet nor protects against elevated energy intake. Although it is easier to overeat on high fat than low fat foods, simply replacing fat with carbohydrate in the diet may not be as protective against overconsumption as the energy density or fat-sugar seesaw arguments suggest.

Effect of altering the variety of sensorially distinct foods, of the same macronutrient content, on food intake and body weight in men.

OBJECTIVE: To examine the effect of increasing the variety of sensorially distinct but nutritionally identical foods on appetite, food intake and body weight, over 7 days, in men. DESIGN: Six younger, lean men (mean (s.d.) age 27.0 (2.9) y; weight 74.7 (3.9) kg; height 1.78 (0.03) m; body mass index (BMI) 23.6 (1.1) kg/m2) and six older, overweight men (mean (s.d.) age 39.7 (2.9) y; weight 89.2 (4.4) kg; height 1.78 (0.04) m; BMI 28.1 (0.5) kg/m2) were each studied three times during a 9 day protocol, whilst resident in the Human Nutrition Unit. On days 1-2, subjects consumed a medium fat (MF) maintenance diet (40% fat, 13% protein and 47% carbohydrate by energy) calculated at 1.6 x resting metabolic rate (RMR). On days 3-9 subjects had ad libitum access to MF foods (550 kJ/100 g) with every item the same macronutrient composition and energy density. Subjects had continuous ad libitum access to 5, 10 or 15 food items per day on the low-variety (LV), medium-variety (MV) and high-variety (HV) treatments, respectively. The order of treatments was randomized across subjects. Subjective hunger was tracked hourly during waking hours using visual analogue scales (VAS). Body weight (as a proxy of changes in energy balance) was measured before eating and after voiding, each morning. RESULTS: Food and energy intake of the 12 men increased as the variety of foods increased, giving mean energy intakes of 10.13, 11.00 and 11.89 MJ/day on the LV, MV and HV treatments, respectively (F(2,20) = 10.32; P < 0.001). This effect was ascribable almost entirely to the lean men. Energy intake amounted to 1.57, 1.76 and 1.97 x RMR in the lean men and 1.33, 1.40 and 1.45 x RMR, for the overweight men on the LV, MV and HV diets, respectively. Weight changes amounted to -0.16, -0.28 and + 0.43 kg (lean) -1.03 and -1.52 kg and -0.66 kg (overweight), on the LV, MV and HV diets, respectively. The overweight men may have constrained their energy intake relative to expected requirements. This may have been due to a congnitive effect or an age effect. There was no significant group or diet effect on subjectively rated hunger. CONCLUSIONS: These data suggest that increasing the variety of sensorially distinct foods that are virtually identical in composition can increase food and energy intake and in the short to medium term can alter energy balance.

Description and evaluation of an experimental model to examine changes in selection between high-protein, high-carbohydrate and high-fat foods in humans.

OBJECTIVE: To develop and test an experimental model designed to detect changes in selection between foods individually enriched in protein, carbohydrate and fat in human subjects. DESIGN: Randomised counterbalanced (Latin square) design. SETTING: The metabolic suite at the Rowett Research Institute's Human Nutrition Unit. SUBJECTS: 16 normal-weight men (mean BMI = 23.5). INTERVENTIONS: Subjects were each studied 4 times in a 2-day protocol. On day 1 subjects received a fixed maintenance diet; on day 2 they received a mandatory intake as breakfast (08.30) plus a drink at 10.30. This comprised 80% of resting energy requirements as high-protein (HP), high-carbohydrate (HC) or high-fat (HF) foods (60% of energy in each case) or an equal mixture (M) of macronutrients, 33% by energy. All mandatory treatments contained the same energy content and density. From 12.30 onwards, subjects had ad libitum access to a counter-balanced selection of three groups of familiar foods (10 HP, 10 HC and 10 HF; 30 foods in total). Most energy in each food was derived from one macronutrient (approximately 60%), the remainder being equally split between the other two macronutrients. RESULTS: Subjects were significantly less hungry before lunch on the HP and M (33% protein) treatments (F3.44 = 7.35; P < 0.001). At lunch, they ate more energy after the HF treatment than after any of the other treatment (F1,38 = 9.00; P = 0.005). This was largely in the form of fat and protein, and to a lesser extent carbohydrate. Subsequent energy intake (EI) were lower on the HF treatment, largely through selection of less fat in the afternoon (F1.42 = 6.90; P=0.012). Daily EIs were similar across treatments. CONCLUSION: This design appears sensitive meal-to-meal to changes in both nutrient and EIs.