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This paper highlights the flow topology above blunt-edged delta wing of VFE-2 configuration when an active flow control technique called 'blower' is applied in the leading edge of the wing. The flow topology above blunt-edged delta wing is very complex, disorganised and unresolved compared to sharp-edged wing. For the sharp leading-edged wing, the onset of the primary vortex is fixed at the apex of the wing and develops along the entire wing towards the trailing edge. However, the onset of the primary vortex is no longer fixed at the apex of the wing for the blunt-edged case. The onset of the primary vortex develops at a certain chord-wise position and it moved upstream or downstream depending on Reynolds number, angle of attack, Mach number and the leading-edge bluntness. An active flow control namely 'blower' technique has been applied in the leading edge of the wing in order to investigate the upstream/downstream progression of the primary vortex. This research has been carried out in order to determine either the flow on blunt-edged delta wing would behave as the flow above sharp-edged delta wing if any active flow control is applied. The experiments were performed at Reynolds number of 0.5×106, 1.0×106 and 2.0×106 corresponding to 9 m/s, 18 m/s and 36 m/s in UTM Low Speed wind Tunnel based on the mean aerodynamic chord of the wing. The results obtained from this research have shown that the blower technique has significant effects on the flow topology above blunt-edged delta wing. The main observation from this study was that the primary vortex has been shifted 20% upstream when the blower technique is applied. Another main observation was the ability of this flow control to delay the formation of the vortex breakdown. [ABSTRACT FROM AUTHOR]

This paper reports on flow visualisation and surface pressure measurements over the upper surface of a blunt-edged delta wing model at high angles of attack. The flow structure above the upper surface of the blunt-edged delta wing was found to be different compared to delta wing with sharp leading edge. The flow becomes more complicated especially in the leading edge region of the wing. Currently, there is no data available to verify if the primary vortex could reach the apex of the wing when the angle of attack is further increased. Most prior experiments were performed at the angles of attack, α, below 23° with only a few experiments that had gone to α = 27°. These prior experiments and some CFD works stipulated that the attached flow continue to exist in the apex region of the delta wing even at very high angles of attack above 23°. In order to verify this hypothesis, several experiments at high angles of attack were conducted in Universiti Teknologi Malaysia Low Speed wind Tunnel (UTM-LST), using a specially constructed VFE2 wing model equipped with blunt leading edges. This series of experiments employed two measurement techniques; the first was the long tuft flow visualisation method, followed by surface pressure measurements. The experiments were performed at Reynolds numbers of 1.0x106 and 1.5x106. During these experiments, several interesting flow characteristics were observed at high angles of attack, mainly that the flow became more sensitive to changes in Reynolds number and the angles of attack of the wing. When the Reynolds number increased from 1x106 to 1.5x106, the upstream progression of the initial point of the main vortex was relatively delayed compared to the sharp-edged delta wing. The experiments also showed that the flow continued to be attached in the apex region up to α = 27°. [ABSTRACT FROM AUTHOR]

The fossil fuel price crisis and emissions control in the transportation sector in Malaysia have become national issues, especially in the transportation sector. As an alternative, using hydrogen mixed with gasoline fuel in conventional combustion engines is a very effective way of improving engine performance and emission control. Generating hydrogen via a chemical reaction between hydrochloric acid and aluminium is a new approach in this study. This methodology has been tested through the mixture application (G + H2) in 10-year-old motorcycles (gasoline) with a modified conventional carburettor engine. The testing of engine performance by chassis dynamometer was done at three levels of experiments: L0: 0 Amp load, L1: 1 Amp load, and L2: 2 Amp load for different engine performances, particularly in identifying quality improvements through the brake thermal efficiency. The study found that the average increase in brake thermal efficiency was 23% higher in the (G + H2) engine compared to gasoline only. The results of this study have proven that the use of hydrogen (Al + HCl) in the stoichiometric ratio has helped to increase combustion efficiency, especially when the oxygen content in the fuel mixture ratio is not adequate during the stroke of power. The successful reduction in fuel consumption, increased engine performance, reduction of pollution and the system's ability to meet the basic needs of the internal combustion engine cycle can be beneficial to the development of the automotive industry, particularly in the transport sector. [ABSTRACT FROM AUTHOR]

The effects of Candida sp. and Blastobotrys sp. starters on fermentation of cocoa beans were studied to determine the potential antibacterial activity of its extracts against foodborne pathogens. The fermentations of cacao beans using Candida sp. and Blastobotrys sp. were conducted for seven days. The observed parameters including pH and temperature monitoring during fermentation, detected active compounds, and invitro antibacterial activity against several foodborne pathogens at on sampling day 0, 3 and 7. Spontaneous fermentation (without starter culture added) was used as control. The pH during fermentation increased from pH 3.00 to 7.97, pH 3.00 to 7.68, and pH 3.00 to 7.54 for spontaneous, Candida sp. and Blastobotrys sp. fermentation respectively. The temperatures of fermentation ranged from 28°C to 33°C, 28°C to 32°C, and 28°C to 32°C for fermentation by spontaneous, Candida sp. and Blastobotrys sp., respectively. Gas Chromatography Mass Spectrometry (GC-MS) analyses showed several active compounds including caffeine, theobromine, gamma-tocopherol, stigmasterol and beta-sitosterols in all three fermentations. Caffeine content was the highest (74.59%) in control fermentation in earlier process. Theobromine content was higher for control fermentation compared to other Candida sp. and Blastobotrys sp. fermentation. Generally, gamma-tocopherol, stigmasterol and beta-sitosterols contents declined in the middle of the fermentation period but increased again towards the end. Fermented cocoa beans extract exhibited antibacterial activity against Bacillus cereus, Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Salmonella enteritica, and Staphylococcus aureus. However, the extracts did not show any antibacterial activity against Listeria monocytogenes and Pseudomonas aeruginosa. In summary, the addition of starter cultures namely Candida sp. and Blastobotrys sp. in fermentation of cocoa beans able to trigger off the active compounds and show potent antibacterial activity against several foodborne pathogens. [ABSTRACT FROM AUTHOR]

Hospital energy consumption is relatively high, while saving energy and reducing cost comprise one of the most important challenges considered by the majority of building designers, engineers, and decision makers. An end-use energy analysis was conducted in a large-scale hospital in Malaysia to identify energy apportioning and energy end use in the areas of air conditioning, lifts, lighting, equipment, and others. The analysis was carried out by assessing the collected desktop and field data as well as some calculations. The Building Energy Index (BEI) was calculated to compare the consumption levels in the selected hospital, which is a typical hospital building, with other hospitals in Malaysia as well as low energy buildings and Malaysian standards. The main energy source in this case study was electricity with a supply of around 75 % of total energy consumption. The current average annual electricity consumed by this hospital was 44,637,966 kWh, out of which 63 % was used by air conditioning systems and 17 % by lighting. The BEI comparison revealed that the calculated BEI of 384 kWh/m/year is significantly higher than Malaysian rating systems and standards which recommend 200 kWh/m/year for hospitals, 135 kWh/m/year for commercial sectors, and is higher than previously observed hospitals with a BEI of less than 300 kWh/m/year. [ABSTRACT FROM AUTHOR]

A high demand for air conditioning systems exists in hot and humid regions because of the warm climate during the year. The high energy consumption of conventional air conditioning system is the reason for our investigation of the solar desiccant cooling system as an energy-efficient cooling system. Four model configurations were considered to determine the best configuration of a solar desiccant cooling system: one-stage ventilation, one-stage recirculation, two-stage ventilation, and two-stage recirculation. These models were stimulated for 8,760 hr of operation under hot and humid weather in Malaysia. Several parameters (i.e., coefficient of performance or COP, room temperature and humidity ratio, and the solar fraction of each system) were evaluated by detecting the temperature and humidity ratio of the different points of each configuration by TRNSYS simulation. The latent and sensible loads of the test room were 0.875 kW and 2.625 kW, respectively. By investigating the simulation results of the four systems, the ventilation modes were found to be higher than the recirculation modes in the one- and two-stage solar desiccant cooling systems. The isothermal dehumidification COP of the two-stage ventilation was higher than that of the two-stage recirculation. Hence, the two-stage ventilation mode desiccant cooling system in a hot and humid area has higher efficiency than the other configurations. [ABSTRACT FROM AUTHOR]

A field study on assessing thermal comfort has been performed on one of the large-scale hospitals in Malaysia, a country where the climate is classified as hot-humid. The main objective of this study was to examine the comfort criteria by American Society of Heating, Air conditioning & Refrigeration Engineers, US (ASHRAE) standards in hot-humid regions and also to find the correlation between predicted mean vote (PMV) according to Fanger’s theory and thermal sensation vote (TSV) according to occupant votes. Therefore, both objective and subjective data was collected in this hospital, and this study’s results have confirmed that the preferred temperature is not necessarily in compliance with a neutral temperature, and people in hot-humid areas would prefer cooler environment to neutral temperature. In addition, by analyzing linear regression, a strong correlation between PMV and TSV was found while R2 = 0.950, and also the neutral temperature point in this field study was around +0.75 on the seven-point ASHRAE thermal sensation scale. [ABSTRACT FROM AUTHOR]

Background and purpose: The guidelines for chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) therapy suggest to use immunoglobulins (IVIg) and steroid as first-line therapies. Patients who do not respond to one of the two drugs should be switched to the other drug. We collected therapeutic outcome data in patients followed at 11 centres in order to document the clinical practice in Italy. Methods: Clinical and electrophysiological data of patients with CIDP were entered into a central database. The clinical outcome (Rankin Scale) and drug side effects (SE) for first- and second-line therapies were recorded. Results: A total of 267 patients were included. The percentage of responders (R) to first-line therapy [steroid or IVIg or plasma exchange (PE)] was 69%; this number increased to 81% when patients who switched to different therapies were included. Overall, the percentage of R to IVIg was similar to R to steroids ( P = 0.07) and higher than R to PE ( P < 0.001). Of the main therapies, PE frequently caused SE (19%), followed by steroids (12.5%) and IVIg (4%). Conclusions: Switching between traditional therapies increases the number of responder patients. IVIg was confirmed to be a therapy with low SE. [ABSTRACT FROM AUTHOR]

Objectives – The aim of the study was to investigate the occurence of anti-tissue transglutaminase antibodies (tTGA) in peripheral nerve disorders, and to correlate them with neurophysiologic findings and anti-glycolipid antibodies. Materials and methods – We examined tTGA immunoglobulin-A serum level from 220 patients with polyneuropathy (acute inflammatory: n = 90; chronic inflammatory: n = 56; non-inflammatory: n = 74) and 110 with motor neuron disease (MND). Results – Seven of the 330 neurologic patients (2.1%, six with polyneuropathy and one with MND) were positive for tTGA. Sixty-one of the 330 neurologic patients (18.4%) had slightly increased tTGA values compared with healthy controls. Increased tTGA values were associated with greater impairment of neurophysiologic findings, but not with the presence of anti-glycolipid antibodies. Conclusions – We found a high prevalence of tTGA reactivity in patients with peripheral nerve disorders or MND. However, we were unable to demonstrate an increased risk of celiac disease in these diseases. [ABSTRACT FROM AUTHOR]

Paddy (unmilled rice), milled rice and maize‐bound 14C residues were prepared using 14C‐succinate‐labelled malathion at 10 and 152 ppm. After 3 months, the bound residues accounted for 12%, 6.5% and 17.7% of the applied dose in paddy, milled rice and maize respectively in the grains treated at 10 ppm. The corresponding values for the 152 ppm were 16.6%, 8.5% and 18.8%. Rats fed milled rice ‐ bound 14C‐residues eliminated 61% of the 14C in the faeces and 28% in the urine. The corresponding percentages for paddy and maize were 72%, 9% and 53%, 41% respectively; indicating that bound residues from milled rice and maize were moderately bioavailable. When rice‐bound malathion residues (0.65 ppm in feed) were administered to rats in a 5 week feeding study, no signs of toxicity were observed. Plasma and RBC cholinesterase activities were slightly inhibited: blood urea nitrogen was significantly elevated in the test animals. Other parameters examined showed no or marginal changes. [ABSTRACT FROM PUBLISHER]