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Background/Objectives: Recent metabolomics technique reveals a plasma-free amino acid (PFAA)-based metabolite signature that is suggestive of altered PFAAs being an early manifestation of obesity-related insulin resistance. However, the PFAA profiles within non-obese, but more insulin-resistant Asians are not well researched. Compared with Caucasians, Asian populations have more central adiposity, which is generally regarded as metabolically more adverse, but the underlying mechanisms remain unclear. In the present study, we examined whether PFAA profiling was at least one important factor mediating central adiposity and insulin resistance, and aid in cardiovascular risk assessment in healthy Asians with normal body weight. Subject/Methods: This was a cross-sectional study. A total of 190 healthy men (n=87 with a mean[plus or minus]s.d. body mass index (BMI) of 23.5[plus or minus]3.5 kg/m.sup.2) and women (n=103 with a mean[plus or minus]s.d. BMI of 21.4[plus or minus]3.7 kg/m.sup.2) residing in Singapore took part in this study. PFAA levels were measured by using an amino acid analyzer. Basic anthropometric measurements, fasting blood glucose, fasting serum insulin and lipid profiles were obtained using standard protocols. Results: Seven out of 18 amino acids were significantly correlated with measures of obesity (for example, waist circumference; waist-to-hip ratio and BMI) in current participants. Among them, the plasma concentrations of five amino acids, including Phe, Tyr, Met, Ala and His were positively associated with waist-to-hip ratio. With the exception of His, which had no association with insulin resistance, Phe, Tyr, Met and Ala were significantly associated with hyperinsulinemia and insulin resistance (P Conclusions: We found that central adiposity was associated with alterations of specific amino acids. As a result, PFAAs may serve as metabolite predictors of hyperglycemia, hyperinsulinemia and dyslipidemia in healthy participants., Author(s): X Bi [sup.1] , S L Tey [sup.1] , Y T Loo [sup.1] , C J Henry [sup.1] [sup.2] Author Affiliations: (1) Clinical Nutrition Research Centre, Singapore Institute for [...]

Pulse oximetry is a monitoring technique used for all patients undergoing intravenous and advanced technique sedation for dental procedures in the UK. In the spring of 2020, pulse oximeters became part of everyday language, as their role in identifying lowered oxygen saturations as a sign of illness in patients with COVID-19 became ubiquitous. By the autumn, however, concerns were raised regarding the accuracy of the oxygen saturation readings for people with darker skin. This led to the launch of a government review into the possibility of racial bias associated with pulse oximetry readings and an MHRA update alerting practitioners to the possibility. [ABSTRACT FROM AUTHOR]

The civil engineering and construction sector, including the railway industry, is seeking innovative approaches to reduce costs on repetitive and labour-intensive tasks and avoid the use of highly qualified staff for simple manual duties. Such tasks can include the visual inspection of tunnels, where the process is still dominated by manual operations. Our work compares Close Range Photogrammetry (CRP) and Terrestrial Laser Scanning (TLS), both performed with low-end sensors to reflect the industry's tendency towards easy to use and easy to maintain hardware. It also analyses the benefits of substituting conventional visual inspections of tunnels with automated survey approaches and computer vision techniques. The project's outcomes suggest that photogrammetry is a valid alternative to laser scanning for visual inspection of concrete segmentally lined tunnels: from the geometric point of view it provides global accuracy at comparable level to laser scanning, in addition it halves the time to generate the 3D model and provides the user with photo-realistic outputs. It is generally more versatile and it is easier to inspect, visualise and navigate the data. The authors argue that the results presented here will push tunnel inspection in the direction of automated approaches with direct benefits on surveying costs as well as Health & Safety (H&S). Utilising available technology supports risk-based asset management and thus ensures safe and operational performance of a railway for passengers to use. [ABSTRACT FROM AUTHOR]

Purpose: The inter-relationships between various implant and bone parameters were evaluated for their influence on the von Mises stress distribution within the mandible using the finite element procedure. The maximum compressive stresses in cancellous and cortical bone were compared to the published stress-strain data to determine bone fracturing status when the maximum (traumatic) loading is applied. Materials and Methods: Parameters considered herein include the implant diameter and length. Also considered are Young's modulus of cancellous bone and that of cortical bone, along with its thickness. The implant-bone system was modeled using two-dimensional plane strain elements, 50% osseointegration between implant and cancellous bone was assumed, and linear relationships were assumed between the stress value and Young's modulus of both cancellous and cortical bone at any specific point within the mandible. Results: Implant length was more influential than implant diameter within cancellous bone, whereas implant diameter was more influential in cortical bone. A ranking of all the parameters indicated that the applied masticatory force had a more significant influence on the stress difference, in both cancellous and cortical bone, than all other parameters. Young's modulus of cortical bone and implant length were least influential in cancellous and cortical bone, respectively. Under traumatic loading, cancellous bone fractured for all parameter combinations. When all parameters were set to their average values, the cortical bone did not fracture under traumatic loading. However, it fractured if all the parameters were all set to the minimum values. Conclusion: Quantitative evaluation and ranking of the major implant and bone parameters will help provide practical guidelines that are useful for the design and testing of dental implants. The study may also be of interest to dental professionals in evaluating possible implant placement options under various clinical scenarios. Int J Oral Maxillofac Implants 2010;25:461-472. [ABSTRACT FROM AUTHOR]

Purpose: The complicated relationships between mandibular bone components and dental implants have attracted the attention of structural mechanics researchers as well as dental practitioners. Using the finite element method, the present study evaluated various bone and implant parameters for their influence on the distribution of von Mises stresses within the mandible. Materials and Methods: Various parameters were considered, including Young's modulus of cancellous bone, which varies from 1 to 4 GPa, and that of cortical bone, which is between 7 and 20 GPa. Implant length (7, 9, 11, 13, and 15 mm), implant diameter (3.5, 4.0, 4.5, and 5.5 mm), and cortical bone thickness (0.3 to 2.1 mm) were also considered as parameters. Assumptions made in the analysis were: modeling of the complex material and geometric properties of the bone and implant using two-dimensional triangular and quadrilateral plane strain elements, 50% osseointegration between bone and implant, and linear relationships between the stress value and Young's modulus of both cancellous and cortical bone at any specific point. Results: An increase in Young's modulus and a decrease in the cortical bone thickness resulted in elevated stresses within both cancellous and cortical bone. Increases in the implant length led to greater surface contact between the bone and implant, thereby reducing the magnitude of stress. Conclusions: The applied masticatory force was demonstrated to be the most influential, in terms of differences between minimum and maximum stress values, versus all other parameters. Therefore loading should be considered of vital importance when planning implant placement. [ABSTRACT FROM AUTHOR]

This work presents the combination of Deep-Learning (DL) and image processing to produce an automated cracks recognition and defect measurement tool for civil structures. The authors focus on tunnel civil structures and survey and have developed an end to end tool for asset management of underground structures. In order to maintain the serviceability of tunnels, regular inspection is needed to assess their structural status. The traditional method of carrying out the survey is the visual inspection: simple, but slow and relatively expensive and the quality of the output depends on the ability and experience of the engineer as well as on the total workload (stress and tiredness may influence the ability to observe and record information). As a result of these issues, in the last decade there is the desire to automate the monitoring using new methods of inspection. The present paper has the goal of combining DL with traditional image processing to create a tool able to detect, locate and measure the structural defect. [ABSTRACT FROM AUTHOR]

Listeriosis and salmonellosis are the major foodborne illnesses worldwide. Over the last decade, increasing reports about the antibiotic resistance of Listeria monocytogenes and Salmonella from diverse sources have prompted public health concerns, especially in developing countries with over reliance or misuse of antibiotic drugs in the treatment of humans and animals. In this study, antibiotic susceptibility profiles of 58 L. monocytogenes and 12 Salmonella Enteritidis strains from vegetable farms and retail markets in Malaysia were testedby the standard disk diffusion method. Listeria monocytogenes isolates were found to exhibit 100% resistance to penicillin G. Also, high resistance patterns were observed for meropenem (70.7%) and rifampicin (41.4%). The multiple antibiotic resistance (MAR) index of L. monocytogenes isolates ranged from 0.11 to 0.56. Besides, the antibiogram results revealed that multidrugresistant (MDR) S. Enteritidis were detected and all the S. Enteritidis isolates demonstrated resistance to at least four antibiotics. Ampicillin, amoxicillin, and trimethoprim failed to inhibit all the S. Enteritidis strains. Salmonella Enteritidis isolates also displayed high resistance to nalidixic acid (75.0%), trimethoprim-sulfamethoxazole (75.0%), and chloramphenicol (66.7%). Findings in this study indicated that vegetables could be potential sources of multidrug resistance of L. monocytogenes and S. Enteritidis, which can be a serious issue and a major concern for public health. Thus, there is a great need for surveillance programs in Malaysia to continuously monitor the antibiotic resistance profiles of important pathogens. [ABSTRACT FROM AUTHOR]

Bacteriophages are the viruses of bacteria and are widely distributed in the biosphere, exhibiting dramatic manifestations both in liquid cultures and on solid media. In this study, bacteriophages were isolated from different types of food (beef, chicken meats, cucumber, lettuce, clam, cockles and shrimp) and sewage samples using 6 reference pathogen strains (Salmonella Enteritidis, Salmonella Typhimurium, Campylobacter jejuni, Vibrio parahaemolyticus, Listeria monocytogenes and Escherichia coli). A total of 29 bacteriophage isolates were obtained and further examined for titer via agar overlay assay. The titers were determined within the range of 108 to 1011 PFU/mL. Our results showed that diverse of bacteriophages are naturally present in a variety of foods. [ABSTRACT FROM AUTHOR]

Salmonella has been reported to be presence both in raw and processed foods worldwide. In this study, the prevalence, quantification and antibiotic susceptibility of Salmonella isolated from raw vegetables or locally known as ulam such as asiatic pennywort (Centella asiatica (L) Urb), water dropwort (Oenanthe javanica (Blume) DC), long bean (Vigna sinensis EndL), and winged bean (Psophocarpus tetragonolobus (L) DC) obtained from retail markets in Selangor, Malaysia were carried out. From 96 samples tested, the overall prevalence of Salmonella spp. was 97.9%, Salmonella Enteritidis was 54.2% and Salmonella Typhimurium was 82.3% respectively. Samples were contaminated with Salmonella ranging from <3 to 2400 MPN/g. Salmonella Enteritidis and Salmonella Typhimurium isolates obtained from the raw vegetables (ulam) were found to exhibit high resistance against ampicillin (100%), erythromycin (100%), amoxicillin/clavunic acid (81.3%), cephalothin (75%), streptomycin (50%) and ciprofloxacin (50%). All Salmonella isolates showed multi drug resistant (MDR) profile with each isolate being resistant to 3 or more antibiotics. The multiple antibiotic resistance (MAR) index of Salmonella isolates ranged from 0.27 to 0.55 for Salmonella Enteritidis and 0.27 to 0.82 for Salmonella Typhimurium. The presence of Salmonella on raw vegetables (ulam) and high antibiotic resistance isolates indicated that raw vegetables could be contaminated and thus imposes possible health risk to local consumers. [ABSTRACT FROM AUTHOR]

A bridge-deterioration approach is to predict the condition ratings and the deterioration pattern of bridge elements for determining optimal maintenance strategies and estimating future funding requirements. To effectively predict long-term bridge performance, an advanced integrated deterioration approach has been developed that incorporates a time-based model, a state-based model with the Elman neural network (ENN) and a backward prediction model (BPM). The proposed approach involves the categorization of the selected inspection records by bridge components, material types, traffic volume, and the construction era. The primary advantage of such categorization is to group similar components together, thereby identifying the common deterioration patterns. A selection process embedded in the proposed approach offers the ability to automatically select the most appropriate model for predicting future bridge condition ratings. To demonstrate the advantage of the proposed approach in predicting long-term bridge performances, case studies are performed using available inspection records. To compare the performance of the proposed approach against the standard Markovian-based deterioration procedure in predicting future bridge condition ratings, a total of 40 bridges with 464 bridge substructure inspection records are selected and used as input. The predicted outcomes are validated by a cross-validation process, which demonstrates that the proposed approach is more accurate than the standard Markovian-based procedure. [ABSTRACT FROM AUTHOR]

Listeria monocytogenes (L. monocytogenes) is an important foodborne pathogen which can cause foodborne listeriosis with high mortality rates especially in susceptible population groups such as pregnant women, elderly and immunocompromised individuals. The biosafety level of L. monocytogenes in chicken offal has becomes a great concern as chicken offal is a cheap source of protein and it is often served as side dishes in South East Asian countries. In Malaysia, the consumption of chicken offal has almost doubled from 5 g per capita per day in the early 1980s to 9 g per capita per day in 2009. In this study, risk assessment was conducted to estimate the risk of acquiring listeriosis from consumption of chicken offal in Malaysia. A microbial survey on the prevalence and concentration of L. monocytogenes in chicken offal were carried out in Selangor, Malaysia over a one-year period (November 2010 to October 2011). It was assumed that there were no seasonal changes in the prevalence and consumption pattern all year round. Assuming that 5.6 million people in Selangor, Malaysia consume a single serving (125 g) of chicken offal per week, it is estimated that in a year there could be 0.61 cases and 1.98 x 10-4 cases of listeriosis per 100,000 population of pregnant woman and immunocompromised individual, respectively. However, the potential for getting listeriosis among the healthy population was very low, only 1.39 x 10-8 cases per 100,000 population. This study demonstrated risk assessment model not only used as a tool to estimate the risk of acquiring illness but it can influence public health surveillance and providing data in setting approriate level of protection. [ABSTRACT FROM AUTHOR]

Probabilistic modelling is one of the most prominent techniques in bridge deterioration forecast. It can be classified into two types, namely, state- and time-based models. Reliability of both modelling techniques in forecasting long-term performance rely heavily on sufficient amount of bridge condition rating data being available together with well-distributed deterioration pattern over the age of bridge. However, it can be problematic when the available condition rating records are insufficient. In order to overcome this problem, an integrated deterioration method incorporating both the state- and time-based models has recently been developed. Despite such development and advancement, certain issues still remain with some cases of given condition data that cannot be used to produce reliable long-term performance curve. Aiming to achieve enhanced prediction performance, an Elman neural networks (ENN) technique is incorporated in the integrated method to replace the third-order polynomial regression function, the latter being the core component for long-term prediction in the state-based model. In the present study, the ENN are able to generate more reliable deterioration patterns than a typical deterministic method. The results demonstrate that the integrated method incorporating ENN are more effective in handling various situations of condition data quantities and distributions for generating long-term performance curves. [ABSTRACT FROM AUTHOR]

Foodborne diseases are mainly caused by bacterial contamination which can lead to severe diarrhea. This study aimed to detect the presence of Shiga toxin-Producing Escherichia coli O157, Escherichia coli non-O157 and virulence gene in raw vegetables. The samples were purchased from wet market and hypermarket in Selangor. The detections were carried out by using the combination methods of Most Probable Number-Polymerase Chain Reaction (MPNPCR). A total of 37(18.5%) samples were found to be contaminated by STEC. Out of these 37 isolates, four (10.8%) of the isolates were E. coli O157 while 33(89.2%) were E. coli non-O157. However, there was no E. coli O157:H7 detected in all the samples. The occurrence of Shiga toxin-Producing E. coli in edible raw vegetables samples suggests the importance of this pathogen in vegetables. Therefore, more studies are required to remove this pathogen from vegetables. [ABSTRACT FROM AUTHOR]

This study aims to determine the presence of extended-spectrum (ESBL) in Klebsiella pneumoniae isolated from raw vegetables by genotypic and phenotypic method. Fifty-three K. pneumoniae isolates that were obtained by plating method were confirmed by PCR. Isolates obtained were screened for their resistance to selected antibiotics. Phenotypic tests for ESBL detection is basically to confirm production of ESBL, in this study two types of antibiotics used which were amoxycillin/clavulanic Acid (AMC, 30 µg) and ceftazidime (CAZ, 30 µg), The resistance were 5/53 (9.4%) and 1/53 (1.9%), respectively. However, it was interesting to observe that none of the K. pneumoniae isolates demonstrated the presence of any of the bla genes by using genotypic method except blaTEM gene has been detected in two isolates out of 53 isolates of K. pneumoniae in this research. [ABSTRACT FROM AUTHOR]

The objective of this research was to evaluate the treatment of p-nitrophenol (PNP) as a sole organic carbon source using a sequencing batch reactor (SBR) with the addition of adsorbent. Two types of adsorbents, namely powdered activated carbon (PAC) and pyrolysed rice husk (PRH) were used in this study. Two identical SBRs, each with a working volume of 10 L, were operated with fill, react, settle, draw and idle periods in the ratio of 2:8:1:0.75:0.25 for a cycle time of 12 h. The results showed that, without the addition of adsorbent, increasing the influent PNP concentration to 200 mg/L resulted in the deterioration of chemical oxygen demand (COD) removal efficiency and PNP removal efficiency in the SBRs. Improvement in the performance of the SBR was observed with the addition of PAC. When the dosage of 1.0 g PAC/cycle was applied, COD removal of 95% and almost complete removal of PNP were achieved at the influent PNP concentration of 300 mg/L. The kinetic study showed that the rates of COD and PNP removal can be described by the first-order kinetics. The enhancement of performance in the PAC-supplemented SBR was postulated to be due to the initial adsorption of PNP by the freshly added and the bioregenerated PAC, thus reducing the inhibition on the microorganisms. The PRH was found to be ineffective because of its relatively low adsorption capacity for PNP, compared with that of PAC. [ABSTRACT FROM AUTHOR]

This article provides a review of the achievements and advancements in dental technology brought about by computer-aided design and the all powerful finite element method (FEM) of analysis. The scope of the review covers dental implants, jawbone surrounding the implant and the biomechanical implant and jawbone interaction. Prevailing assumptions made in the published finite element analysis (FEA) and their limitations are discussed in some detail which helps identify the gaps in research as well as future research direction. [ABSTRACT FROM AUTHOR]

This work investigates the non-linear mechanical behavior of oil palm mesocarp fibers (OPMF) using tensile tests, microstructure observation, and finite element models. The micrograph images showed the fiber’s surface with partly embedded silica bodies, while the cross section contained cell wall structures. Viscoelastic behavior was observed when the fibers were relaxed over time after being stretched, whereas the stress--strain curves from the cyclic tests indicated permanent set (plastic strain) due to the fibers’ deformation. Finite element models were developed comprising single particles (2D and 3D) and 2D multi-particle geometries representing silica bodies embedded in a matrix representing the fiber. The modeling results suggested that silica bodies do not contribute much to the integrity of OPMF, highlighting the need to have a more complex model that considers cellular structures of the fibers and a constitutive relationship of cellulose, hemicelluloses, and lignin.

Employs a pilot-scale biotrickling filter, packed with pail rings, set up at a wastewater treatment plant in Singapore to investigate its effectiveness for treatment of odorous sewage air. Performance unmder normal operating sewage off-gas conditions; Performance under high hydrogen sulfide loading conditions with sewage off-gas; Performance under shock hydrogen sulfide loading conditions with sewage off-gas.

Coarse and fine aggregates generated from crushed concrete products for new concrete can be generally accepted only when the properties of recycled aggregate concrete, in addition to the relationships between different properties of such a concrete, are well understood. The results of an experimental investigation into the relationship of compressive strength to ultrasonic pulse velocity and to rebound number is presented in this paper. It has been observed that for the water-cured concrete the strength-pulse velocity relationship is influenced by the use of the recycled aggregate. For the same value of the pulse velocity, the strength of recycled aggregate concrete is higher than that for the natural aggregate concrete. On the other hand, the strength-rebound number relationship is not affected by the aggregate type used. The combined method of pulse velocity and rebound number for strength estimation is also evaluated. [ABSTRACT FROM AUTHOR]