The influence of water-to-cement ratio (w/c) on the compressive strength of cement-biochar-spent resins matrix was
investigated. Spent resins waste from nuclear reactor operation was solidified using cement with w/c ranging from 0.35
to 0.90 by weight. In this study, biochar was used as a cement admixture. Some properties of spent resins and biochar
were determined prior to the formulation study. Compressive strength of harden cement-biochar-spent resins matrix
was determined at 28 days. The compressive strength of cement-biochar-spent resins matrix was found to depend on the
w/c and the amount of spent resins added to the formulation. The immersion test of cement-biochar-spent resins matrix
showed no significant effects of cracking and swelling. The compressive strength of the cement-biochar-spent resins
matrix increased after two weeks in water immersion test.
The Association of South East Asian Nations (ASEAN) was formed in 1971, and 10 years
later the ASEAN Federation for Psychiatry and Mental Health (AFPMH) was formally
launched. This article reviews the objectives, structure, membership, and the principles of
rotational participation and responsibility of the AFPMH, which has just celebrated its jubilee anniversary last year. Twenty-six years have passed, and the AFPMH has achieved many successes, including the congress, which is currently held every two years, and the ASEAN Journal of Psychiatry, which may be the oldest regional journal in the Asian continent. The bright future of ASEAN psychiatry is expected but relies heavily on the unity and commitment of all individual psychiatric associations within the ASEAN.
Until today there are still a high percentage of oral microorganisms have not been identified due to inability to isolate using the cultural method. However, identification of uncultivable microorganisms associated with disease will permits clinicians for a more accurate diagnosis, treatment and preventive measures. Unculturable microorganisms are also involved in disease and may account for treatment failure since their susceptibility to antimicrobial agents would be unknown. Thus, the opportunity for a rational approach to the treatment of disease relies on the state of knowledge concerning its aetiology and pathogenesis. Recently developed molecular methods have made it possible to characterise mixed microflora in their entirety, including the substantial numbers of unculturable bacteria. The development of rapid molecular methods like PCR provides a reliable identification of unculturable microorganisms. This paper will review the current literature regarding the PCR techniques used to identify uncultivable oral microflora.
The aim of this study was to systematically review the available studies measuring the bond strength of orthodontic bracket-adhesive system under different experimental conditions in vivo. Literature search was performed in four different databases: PubMed, Web of Science, Cochrane, and Scopus using the keywords - bond strength, orthodontic brackets, bracket-adhesive, and in vivo. A total of six full-text articles were selected based on the inclusion and exclusion criteria of our study after a careful assessment by the two independent reviewers. Data selection was performed by following PRISMA 2009 guidelines. Five of the selected studies were clinical trials; one study was a randomized clinical trial. From each of the selected articles, the following data were extracted - number of samples, with the type of tooth involved materials under experiment methods of measurement, the time interval between bonding and debonding orthodontic brackets, mode of force application, and the bond strength results with the overall outcome. The methodological quality assessment of each article was done by the modified Downs and Black checklist method. The qualitative analyses were done by two independent reviewers. Conflicting issues were resolved in a consensus meeting by consulting the third reviewer (MKA). Meta-analysis could not be performed due to the lack of homogenous study results. The review reached no real conclusion apart from the lack of efforts to clinically evaluate the bonding efficiency of a wide range of orthodontic bracket-adhesive systems in terms of debonding force compared to laboratory-based in vitro and ex vivo studies.
A good adhesive is an important factor to consider in orthodontic bonding. Frequent bracket failure prolongs treatment duration and causes inconvenience to patient and operator. This study aimed to compare the effectiveness of two bonding agents, i.e. the self etching primer (SEP) and the conventional etch and bond (CEB) by monitoring the incidence, time and
sites of bracket failure. Eighty orthodontic patients were recruited after informed consent were obtained. A randomized split mouth technique was used where one side was bonded with CEB agent, while the other side was bonded using SEP agent. All bonded brackets were examined every 4 weeks for 20 months. Incidence of bracket failure was noted and
comparison between the two groups was done using paired t-test. Time and frequent site of failure were also assessed. Out of 1314 brackets, only 33 brackets were debonded with 16 from SEP group and 17 from CEB group which statistically insignificant (p>0.05). Almost 55% of bracket failure occurred during the first 3 months after bonding for both adhesives
with lower premolars was most the frequent site to fail in both adhesives (39.4%). Bracket bonded on the left side failed significantly compared to the right side. In conclusion, both self-etching primer and conventional acid-etch bonding agents are equally effective in retaining brackets clinically. Bracket failure mostly occurres during the first 3 months after bonding. The premolar brackets and the left side are mostly debonded when compared to other sites.
The Malaysian Journal of Medical Sciences and the Orient Neuron Nexus have amalgated to publish a yearly special issue based on neuro- and brain sciences. This will hopefully improve the quality of peer-reviewed manuscripts in the field of fundamental, applied, and clinical neuroscience and brain science from Asian countries. One focus of the Universiti Sains Malaysia is to strengthen neuroscience and brain science, especially in the field of neuroinformatics.
This study aims to synthesize and characterize lignin-decorated zinc oxide nanoparticles before incorporating them into resin-modified glass ionomer cement (RMGIC) to improve their anticariogenic potential and mechanical properties (shear bond strength and microhardness). Probe sonication was used to synthesize lignin-decorated zinc oxide nanoparticles which were then characterized via scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. Following characterization, these were incorporated in RMGIC (Gold label, Fuji II LC). Three major groups, experimental group A (EGA), experimental group B (EGB), and control group (CG), were outlined. EGA and EGB were divided into numbered subgroups based on the ascending concentrations of nanoparticles (5, 10, and 15%) of lignin-coated zinc oxide and zinc-oxide, respectively. CG served as a control and comprised cured RMGIC samples without any incorporation. Anticariogenic analysis was conducted on experimental RMGIC samples via disk-diffusion (n = 3) and direct contact test (n = 3) against Streptococcus mutans (ATCC 25175). Optical density values for days 1, 3, and 5 were recorded via a UV-Vis spectrophotometer. A shear bond strength test was performed using 35 premolars. The adhesive remnant index was used to estimate the site of bond failure. For the Vickers microhardness test (n = 3), 100 g of load at 10 s dwell time was set. Atomic absorption spectroscopy was performed over 28 days to determine the release of zinc from the samples. All tests were analyzed statistically. The anticariogenic potential of EGA and EGB was significantly greater (p ≤ 0.05) than that of the control. The shear bond strength test reported the highest value for EGA15 with all groups exhibiting failure at the bracket/RMGIC interface. The microhardness of EGA15 yielded the highest value (p ≤ 0.05). Release kinetics displayed a steady release with EGB15 exhibiting the highest value. The EGA and EGB samples displayed good anticariogenic potential, which was sustained for 28 days without any deleterious effect on the shear bond strength and microhardness.
To evaluate the shear bond strength between the dentin substrate and computer-aided design and computer-aided manufacturing feldspathic ceramic and nano resin ceramics blocks cemented with resin cement.
The effect of filler content and storage conditions such as drying, storing in water and thermal cycling on linear dimensional changes were investigated and evaluated. The dimensional accuracy studies were performed using a specific designed mould and a coordinate measuring machine. The findings gave support to the view that tiller content is an important factor influencing the physical and mechanical properties of the composite inlay material. The higher tiller content gave less polymerization shrinkage. The greatest linear shrinkage recorded was 0.79 %. The average linear shrinkage (in air, water and thermal cycling) for 79 % filler Prisma AP.H was 0.33 %, for 65 % tiller Prisma AP.H was 0.35 % and for 50 % filler Prisma AP.H was 0.42 %. Generally, dimensional changes was greatest when stored dry. This was followed by materials which were thermal cycled. The least dimensional change recorded was when the materials were stored in water.
In recent years image acquisition in close range photogrammetry relies on digital sensors such as digital cameras, video cameras, CCD cameras etc that are not specifically designed for photogrammetry. This study is performed to evaluate the compatibility of the digital metric camera and non-metric camera for the purpose of mapping meandering flume, using close range photogrammetric technique and further, to determine the accuracy that could be achieved using such a technique. The meandering flume provides an opportunity to conduct an experimental study in a controlled environment. In this study, the digital images of the whole meandering flume were acquired using a compact digital camera - Nikon Coolpix S560, a Single Lens Reflex (SLR) Nikon D60 and also a metric digital camera Rollei D30. A series of digital images were acquired to cover the whole meandering flume. Secondary data of ground control points (GCP) and check points (CP), established using the Total Station technique, was used. The digital camera was calibrated and the recovered camera calibration parameters were then used in the processing of digital images. In processing the digital images, digital photogrammetric software was used for processes such as aerial triangulation, stereo compilation, generation of digital elevation model (DEM) and generation of orthophoto. The whole process was successfully performed and the output produced in the form of orthophoto. The research output is then evaluated for planimetry and vertical accuracy using root mean square error (RMSE). Based on the analysis, sub-meter accuracy is obtained. It can be concluded that the differences between the different types of digital camera are small . As a conclusion, this study proves that close range photogrammetry technique can be used for mapping meandering flume using both the metric digital camera and non-metric digital camera.
Understanding the nexus CO2 emissions and economic growth helps economies in formulating energy policies and developing energy resources in sustainable ways. Although during recent years, numerous of the previous studies have been very thoroughly investigated the nexus between economic growth and CO2 emissions, there is a lack of research regarding the qualitative systematic review and meta-analysis in these areas. The main purpose of this review paper is to present the comprehensive overview of the relationship between CO2 emissions and economic growth. In this regard, the Web of Science database has been chosen and a qualitative systematic and meta-analysis method which called "Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)" has been proposed. Therefore, a review of 175 published articles appearing in 55 scholarly international journals between 1995 and 2017 has been achieved to reach a broad review of the nexus between economic growth and CO2 emissions with other indicators. Consequently, the selected articles have been categorized by the author name, the year of publication, data duration, types of techniques, data analysis method, the name of indicators, country, scope (individual country and multi-countries), journals, results, and outcome in which they appeared. The results of this paper demonstrated that the nexus between CO2 emissions and economic growth gives reasons for policy options that have to reduce emissions by imposing limiting factors on economic growth as well. Given the fact that bidirectional causality exists, as far as economic growth increases or decreases, further CO2 emissions are stimulated in higher or lower levels and consequently, a potential reduction of the emissions should have an adverse influence on economic growth.
A major issue of machinery fault diagnosis using vibration signals is that it is over-reliant on personnel knowledge and experience in interpreting the signal. Thus, machine learning has been adapted for machinery fault diagnosis. The quantity and quality of the input features, however, influence the fault classification performance. Feature selection plays a vital role in selecting the most representative feature subset for the machine learning algorithm. In contrast, the trade-off relationship between capability when selecting the best feature subset and computational effort is inevitable in the wrapper-based feature selection (WFS) method. This paper proposes an improved WFS technique before integration with a support vector machine (SVM) model classifier as a complete fault diagnosis system for a rolling element bearing case study. The bearing vibration dataset made available by the Case Western Reserve University Bearing Data Centre was executed using the proposed WFS and its performance has been analysed and discussed. The results reveal that the proposed WFS secures the best feature subset with a lower computational effort by eliminating the redundancy of re-evaluation. The proposed WFS has therefore been found to be capable and efficient to carry out feature selection tasks.
Similarity measurement is a critical component in any case-based reasoning (CBR) system. CBR is
a superior technique for solving new problems based on previous experiences. Main assumption in
CBR relies on the hypothesis that states similar problems should have similar solutions. This paper
describes a comparative analysis on several commonly used similarity measures (Canberra, Clark, and Normalized Euclidean distance) in retrieving phase of the case-based reasoning approach to facilitate supplier selection. In addition, the proposed agent-based supplier selection framework was designed to use customer’s defined weights to evaluate the price, volume, quality grade, and delivery date of supply materials, and also provide them with alternative products which are closest to their first order if it was out of stock. Finally, based on the proposed framework, a numerical example of the used approach is illustrated.