Scopus

The suitability of a PCR procedure using a pair of primers targeting the hilA gene was evaluated as a means of detecting Salmonella species. A total of 33 Salmonella strains from 27 serovars and 15 non-Salmonella strains from eight different genera were included. PCR with all the Salmonella strains produced a 784 bp DNA fragment that was absent from all the non-Salmonella strains tested. The detection limit of the PCR was 100 pg with genomic DNA and 3 3 104 c.f.u. ml 1 with serial dilutions of bacterial culture. An enrichment-PCR method was further developed to test the sensitivity of the hilA primers for the detection of Salmonella in faecal samples spiked with different concentrations of Salmonella choleraesuis subsp. choleraesuis serovar Typhimurium. The method described allowed the detection of Salmonella Typhimurium in faecal samples at a concentration of 3 3 102 c.f.u. ml-1. In conclusion, the hilA primers are specific for Salmonella species and the PCR method presented may be suitable for the detection of Salmonella in faeces.

The aim of the present study was to determine the oral health status of 16-year-old Malaysian school children. The prevalence of caries was 75.5%. More than 60% of subjects had caries experience by teeth (DMFT) scores of 0-3. The largest component of the DMFT and caries experience by surface index was the filled component. Females had higher caries prevalence and caries scores than males. The mouth and tooth prevalences of enamel defects were 56% and 21.8%, respectively. The most common type of enamel defects observed were diffuse opacities, affecting 95.5% of affected subjects and 92.1% of affected teeth. One-third of subjects had healthy gingival conditions, 8.6% had bleeding gingivae, 55.1% had calculus and 3% had pockets. Less than 1% of subjects wore or required dentures. Cleft lip and/or palate was uncommon. This study shows that the prevalence of caries and DMFT scores have declined over the last 30 years.

There are many factors contribute to the virus spread and infection. One of the big challenges in confronting computer viruses is to educate user. It needs a lot of effort to educate user about computer virus. The researchers have produced ECOVP which is to help user handle virus problem and the targets users including home user, non-IT literature background and IT personnel needs in handling virus incident. Researchers had studied what are the information needs to be process, so we could use them to generate the knowledge on how to handle the virus problem. We had identified seven important criteria for user need to understand in capable for them facing the computer virus. However, this paper is focusing on virus attack on Windows platform only. � 2006 IEEE.

This study was conducted on selected local herbs such as ulam raja (Cosmos caudatus), kesum (Polygonum minus), selom (Oenanthe javanica), pegaga (Centella asiatica) and curry leaves (Murraya koenigii) to investigate their antioxidative activities. The water extracts of the herbs were analysed for total phenolic content, reducing antioxidant power, ferric thiocyanate (FTC) and the thiobarbituric acid (TBA) test was also accried out. Polygonum minus showed the highest total phenolic content and reducing power among the herbs. Increasing the concentration of the extracts resulted in increased Fe3+ reducing antioxidant power for all the herbs. FTC and TBA tests on the extracts during seven days of storage showed that all the herbs extracts had the ability to reduce oxidation compared to the control (P < 0.05). From the FTC analysis, Murraya koenigii leaves was best in reducing the oxidation rate (67.67%) compared to the other herbs studied. Analysis of TBA showed that Centella asiatica extract had the highest antioxidant effect. However, both TBA and FTC analysis for these two herbs showed no significant difference (P > 0.05) from Polygonum minus and butylated hydroxyanisole (BHT) a synthetic antioxidant. Correlation analysis showed positive correlations between amount of total phenolic content and reducing power (r = 0.75) and antioxidative activities (r = 0.58) in linoleic acid emulsion system. This shows that antioxidative activities of these Malaysian herbal plants especially Polygonum minus may be a potential source of natural antioxidants with similar characteristics to the synthetic antioxidant, BHT.

Inflammatory bowel disease (IBD) is a generic term that refers to Crohn's disease and ulcerative colitis. The precise aetiology of these diseases remains unknown. However, both are believed to result from the interaction of environmental factors, immune response and genetic factors. The impact of environmental factors such as smoking, diet, drug, geographical and social status, stress, microbial agents, intestinal permeability and appendectomy appear to be associated with IBD pathogenesis. Some varieties of these factors modify gene expression in susceptible individuals and modulate the effector function of the intestinal immune system. To understand the IBD pathogenesis, several studies have reported that luminal bacteria play an essential role in development of IBDs. Various bacterial pathogens have been incriminated but the results obtained have been conflicting. No specific pathogen has been identified as being causally associated with IBD. However, it is widely thought that, in IBD cases, individuals appear to lose the normal tolerance to commensal bacteria leading to an elevated inflammatory response. By contrast to healthy gut, the symbiotic relationship between the host and the commensal bacteria exposure leads to the down-regulation of inflammatory genes. Therefore, this brief review focuses on the microbial aetiology of IBD. � 2007 Lippincott Williams & Wilkins, Inc.

The possible relationships between the main emulsion components (namely, Arabic gum, xanthan gum, and orange oil) and the physicochemical properties of orange beverage emulsion were evaluated by using response surface methodology. The physicochemical emulsion property variables considered as response variables were emulsion stability, viscosity, fluid behavior, ?-potential, and electrophoretic mobility. The independent variables had the most and least significant (p < 0.05) effect on viscosity and ?-potential, respectively. The quadratic effect of orange oil and Arabic gum, the interaction effect of Arabic gum and xanthan gum, and the main effect of Arabic gum were the most significant (p < 0.05) effects on turbidity loss rate, viscosity, viscosity ratio, and mobility, respectively. The main effect of Arabic gum was found to be significant (p < 0.05) in all response variables except for turbidity loss rate. The nonlinear regression equations were significantly (p < 0.05) fitted for all response variables with high R2 values (>0.86), which had no indication of lack of fit. The results indicated that a combined level of 10.78% (w/w) Arabic gum, 0.56% (w/w) xanthan gum, and 15.27% (w/w) orange oil was predicted to provide the overall optimum region in terms of physicochemical properties studied. No significant (p > 0.05) difference between the experimental and the predicted values confirmed the adequacy of response surface equations. � 2007 American Chemical Society.

Headspace solid-phase microextraction (HS-SPME) gas chromatography was used to analyze target flavor compounds in orange beverage emulsion. The effects of SPME fiber (PDMS 100 μm, CAR/PDMS 75 μm, PDMS/DVB 65 μm and DVB/CAR/PDMS 50/30 μm), adsorption temperature (25-45 °C), adsorption time (5-25 min), sample concentration (1-100%), sample amount (5-12.5 g), pH (2.5-9.5), salt type (K2CO3, Na2CO3, NaCl and Na2SO4), salt amounts (0-30%) and stirring mode were studied to develop HS-SPME condition for obtaining the highest extraction efficiency and aroma recovery. For the head space volatile extraction, the optimum conditions were: CAR/PDMS fiber, adsorption at 45 °C for 15 min, 5 g of diluted beverage emulsion (1:100), 15% (w/w) of NaCl with stirring and original pH 4. The main volatile flavor compounds were: limonene, 94.9%; myrcene, 1.2%; ethyl butyrate, 1.1%; γ-terpinene, 0.41%; linalool, 0.36%; 3-carene, 0.16%; decanal, 0.12%; ethyl acetate, 0.1%; 1-octanol, 0.06%; geranial, 0.05%; β-pinene, 0.04%; octanal, 0.03%; α-pinene, 0.03%; and neral, 0.03%. The linearity was very good in the considered concentration ranges (R2 ≥ 0.97). Average recoveries ranged from 88.3% to 121.7% and showed good accuracy for the proposed analytical method. Average relative standard deviation (RSD) for five replicate analyses was found to be less than 14%. The limit of detection (LOD) ranged from 0.06 to 2.27 mg/l for all volatile flavor compounds and confirmed the feasibility of the HS-SPME technique for headspace analysis of orange beverage emulsion. The method was successfully applied for headspace analysis of five commercial orange beverage emulsions.

The main and interaction effects of main emulsion components namely Arabic gum content (13-20%, w/w, x1), xanthan gum content (0.3-0.5%, w/w, x2) and orange oil content (10-14%, w/w, x3) on beverage emulsion characteristics were studied using the response surface methodology (RSM). The physicochemical properties considered as response variables were: ?-potential (Y1), conductivity (Y2), emulsion stability (Y3), size index (Y4) and pH (Y5). The results indicated that the response surface models were significantly (p < 0.05) fitted for all response variables studied. In contrast with ?-potential and pH, the independent variables had the most significant (p < 0.05) effect on size index. Regression models describing the variations of the responses variables showed high coefficient of determination (R2) values ranging from 0.866 to 0.960. The main effect of Arabic gum followed by its interaction with orange oil was observed to be significant (p < 0.05) in most of response surface models. Therefore, the concentration of Arabic gum should be considered as a critical variable for the formulation of orange beverage emulsion in terms of the emulsion characteristics studied. The overall optimum region resulted in a desirable orange beverage emulsion was predicted to be obtained by combined level of 10.78% (w/w) Arabic gum, 0.24% (w/w) xanthan gum and 12.43% (w/w) orange oil. No significant (p > 0.05) difference was found between the experimental and predicted values, thus ensuring the adequacy of the response surface models employed for describing the changes in physicochemical properties as a function of main emulsion component contents. � 2007 Elsevier B.V. All rights reserved.

In the present work, the effect of type and concentration of two hydrocolloids namely pectin (1.5%, 3% and 4.5%) and CMC (0.1%, 0.3% and 0.5%) on physical stability, turbidity loss rate, cloudiness and flavor release of orange beverage emulsion was investigated during six months storage. From the turbidity loss rate results, the orange beverage emulsions containing 4.5% and 1.5% (w/w) pectin showed the highest and least storage stability, respectively. In contrast to the first two months storage, the replacement of both supplementary emulsion components resulted in a significant (p < 0.05) increase in turbidity loss rate of all orange beverage emulsions, thus indicating a decrease in capability of beverage emulsion to maintain the cloudiness during storage. The cloudiness of all samples significantly (p < 0.05) decreased during storage. The differences between the volatile release behaviors of target volatile compounds from orange beverage emulsions having different formulations indicated that the overall volatile flavor release was strongly influenced by the emulsion composition. This finding may be explained by the interactions between emulsion matrix and volatile flavor compounds. The release contents of most of target flavor compounds were significantly (p < 0.05) decreased during storage, especially for the aldehyde compounds studied (i.e. octanal, decanal, neral, geranial). � 2007 Elsevier Ltd. All rights reserved.

The influence of main emulsion components namely Arabic gum (13-20% w/w), xanthan gum (0.3-0.20% w/w) and orange oil (10-14% w/w) on semi-quantitative headspace analysis of target volatile flavor compounds released from a model orange beverage (diluted orange beverage emulsion) was evaluated by using a three-factor circumscribed central composite design (CCCD). For optimization procedure, the peak area of 13 volatile flavor compounds (i.e. ethyl acetate, ?-pinene, ethyl butyrate, ?-pinene, 3-carene, myrcene, limonene, ?-terpinene, octanal, decanal, linalool, neral and geranial) were considered as response variables. The response surface analysis exhibited that the significant (p < 0.05) second-order polynomial regression equations were successfully fitted for all response variables except for ethyl butyrate. A satisfactory coefficient of determination (R2) ranged from 0.831 to 0.969 (>0.8) was obtained for the response variables studied. No significant (p > 0.05) lack of fit was indicated for the reduced models except for the models fitted for limonene and linalool. This observation confirmed an accurate fitness of the reduced response surface models to the experimental data. The multiple response optimizations indicated that an orange beverage emulsion containing 15.87% (w/w) Arabic gum, 0.5% (w/w) xanthan gum and 10% (w/w) orange oil was predicted to provide the minimum overall flavor release. � 2007 Elsevier Ltd. All rights reserved.

According to the agency theory, separation of ownership and control gives rise to manager's incentives to select and apply accounting estimates and techniques that can increase their own wealth. This issue has become more important in recent years as more firms are listed on stock exchanges as public firms. This study examines the association between the level of managerial ownership and earnings management activities, represented by the magnitude of discretionary accounting accruals in Malaysian listed firms. The results show that managerial ownership is negatively associated with the magnitude of accounting accruals. However, this study finds that managerial ownership is less important in large-sized firms compared to small-sized firms. This finding suggests that large-sized firms demand and use better corporate governance mechanisms due to higher agency conflicts, and, therefore, less managerial ownership is needed for control. As part of the ownership structure, this study also examines the roles of block and foreign ownerships in relation to the magnitude of discretionary accounting accruals.

This paper focuses on the development of an effective methodology to determine the optimum levels of three independent variables leading to (a) maximize turbidity, (b) minimize polydispersity index (PDI) and (c) obtain the target value for average particle size and density of orange beverage emulsion. A three-factor central composite design (CCD) was employed to determine the effect of Arabic gum content (7-13% w/w), xanthan gum content (0.1-0.3% w/w) and orange oil content (6-10% w/w). The emulsion properties studied as response variables were: turbidity (Y1), average particle size (Y2), PDI (Y3) and density (Y4). The response surface analysis was carried out to create efficient empirical models for predicting the changes of response variables. In general, analysis of variance (ANOVA) showed high coefficients of determination values (R2) in the range of 0.922-0.975 for the response surface models, thus ensuring a satisfactory adjustment of the polynomial regression models with the experimental data. The results of regression analysis indicated that more than 92% the response variation could be explained by the models. The results also indicated that the linear term of xanthan gum was the most significant (p<0.05) variable affecting the overall responses. The multiple optimization results showed that the overall optimum region with high total desirability (D=0.92) was found to be at the combined level of 13.88% w/w Arabic gum content, 0.27% w/w xanthan gum content and 11.27% w/w orange oil content. Under the optimum condition, the corresponding predicted response values for turbidity, average particle size, PDI and density of the desirable orange beverage emulsion were 129.55, 988, 0.261 and 1.03, respectively. For validation of the models, the experimental values were compared with predicted values to check the adequacy of the models. The experimental values were found to be in agreement with those predicted, thus indicating suitability of the models employed using response surface methodology (RSM) for optimizing the physical properties of the orange beverage emulsion. � 2007 Elsevier Ltd. All rights reserved.

In this study, Taguchi method was used to identify the several factors that may affect the performance of Destination Sequence Distance Vector (DSDV) routing protocol. The performance of DSDV routing protocol in mobile ad hoc networks were greatly influence by factors such as node speed, node pause time and traffic load. Problem statement: By using orthogonal experimental design and analysis techniques, the protocol performance can be analyzed with more objective conclusion through only a small number of simulation experiments. Approach: The performance was measured with respect to packet delivery ratio. Analysis of variance (ANOVA) was carried out to identify the significant factors affecting the response and the best possible factor level combination was determined through analysis of the signal-to-noise ratio. Results: It was found that the traffic load has a stronger influence on the packet delivery ratio, followed by the pause time. Conclusions/Recommendations: The optimal setting of the best performance is determined. The optimal setting has resulted in increased packet delivered. These findings demonstrate that Taguchi method may be valuable tool for the investigation of main effect or interactions of multiple factors in the performance of mobile ad hoc network routing protocols. � 2008 Science Publications.

Wireless sensor network (WSN) consists of a large number of sensor nodes densely deployed closed to each other. Each sensor carries out task such as monitoring and collecting data, or detecting and identifying certain events. While nodes in operation, they will detect each other and form a communication network. The problem arises when two or more nodes send data at the same times over the same channel. Here, the task of Medium Access Control (MAC) is crucial to efficiently manage the transmission among nodes and reduce collision. However, most of the MAC protocols designed for WSN are for static environment. Applying the existing MAC protocol to application such as medical care and disaster response will raise few problems where the moving node will experience delay in sending and receiving data. Thus, there is a need to design a protocol which can tolerate the node moving without degrading network performance. The aim of this paper is to evaluate the capability of MAC protocol issues especially for the popular MAC protocol for sensor network, S-MAC and IEEE 802.15.4. �2008 IEEE.

The focus of this paper is on the implementation of Bluetooth as a tool to provide m-advertising (mobile advertising). The paper attempts to introduce the implementation of Bluetooth m-advertising system based on user-driven concept using pull-based approach. User-driven concept gives flexibility to end users to select the preferred advertisements from the server while pull-based m-advertising provides advertisement to users based on their willingness and request. This paper also will address two issues in push-based m-advertising systems, which are spamming and time limit. � 2008 IEEE.

Solid-phase microextraction (SPME) coupled to gas chromatography has been applied for the headspace analysis (HS) of 12 target flavour compounds in a model orange beverage emulsion. The main volatile flavour compounds studied were: acetaldehyde, ethyl acetate, ?-pinene, ethyl butyrate, ?-pinene, myrcene, limonene, ?-terpinene, octanal, decanal, linalool and citral (neral plus geranial). After screening the fibre type, the effect of other HS-SPME variables such as adsorption temperature (25-55�C), extraction time (10-40 min), sample concentration (1-100% w/w), sample amount (5-10 g) and salt amount (0-30% w/w) were determined using a two-level fractional factorial design (25-2) that was expanded further to a central composite design. It was found that an extraction process using a carboxen-polydimethylsiloxane fibre coating at 15�C for 50 min with 5 g of diluted emulsion 1% (w/w) and 30% (w/w) of sodium chloride under stirring mode resulted in the highest HS extraction efficiency. For all volatile flavour compounds, the linearity values were accurate in the concentration ranges studied (r2 > 0.97). Average recoveries that ranged from 90.3 to 124.8% showed a good accuracy for the optimised method. The relative standard deviation for six replicates of all volatile flavour compounds was found to be less than 15%. For all volatile flavour compounds, the limit of detection ranged from 0.20 to 1.69 mg/L. Copyright � 2008 John Wiley & Sons, Ltd.

Optically active (-)-menthyl butyrate was synthesized by enantioselective esterification of racemic (±)-menthol and butyric anhydride using lipase from Candida rugosa immobilized onto epoxy-activated supports of Eupergit C and Eupergit C 250 L through physical adsorption method. The effects of various temperature, storage condition, stability in organic solvent and lipase recyclability were investigated for their influence on the enzymatic enantioselective formation of (-)-menthyl butyrate. The immobilized lipases retained high catalytic activity of up to 31% yield and 100% enantiomeric excess of the desired product, and showed better stability compared to the native lipase. They also exhibited about 50% retained activity even after incubation at higher temperatures, storage at room temperature and after long incubation in hexane. Immobilized lipases also showed considerably efficient reusability.

Telecom Service Providers (TSPs) are facing big challenges in today's telecom markets due to the introduction of packet-based network Users demand more on higher and flexible bandwidth together with high Quality of Service (QoS). These problems require TSPs to seek new network technology that can meet such challenges. Metro Ethernet has been regarded as the technology of choice due to its universality and high flexibility. This paper is about the design of Telekom Malaysia's TM600E that is a lOGigabit switch to be used as the Edge Provider Edge (EPE) device in the Metro Ethernet Network. The Advanced Telecom Computing Architecture (ATCA) has been chosen for providing the open architecture platform. Performance testing conducted confirms that the switch has high throughput, low latency, and low packet loss. �2008 IEEE.

This paper investigates the differences between the impacts of transparency in the US and European Corporate Bond Markets by studying the criticisms of transparency in the US markets from European markets perspective. The study makes two assumptions namely as the level of understanding on transparency in the European market increase; the spreads decrease and the volume of trading do not decrease. Then the study construct a regression on the data sets on all of subset of the European market selected that consists of the average best bid-ask spread (presented in proportional spread) and the number of trading volumes. The results from methodology are giving favorable results or advantages of implementation of transparency that is consistent with the phenomenon experienced by US corporate bond markets. Thus, it can be concluded that it would be optimal to introduce transparency in the markets but with some limited post-trade transparency.

This research assessed the potential of natural colour extract of Hibiscus sabdariffa L. (roselle) as sensing material. The pH sensor was developed based on the use of natural reddish colour in roselle's calyx, delphinidin-3-sambubioside immobilised in a glass fibre filter paper. In free solution, roselle extract was characterised by using UV-visible spectrophotometer to study the effect of pH, extract concentration, response time, repeatability and photostability. The study showed that natural colour extract can be used as sensing material for the development of an optical pH sensor.