Exposure to industrial air pollutants is a public health concern particularly in children due to their immaturity of respiratory systems. The distance between their school and home from the industrial area will elevate the risk of airway inflammation among children. This study aims to determine the exposure of Industrial Air Pollutants (PM10, PM2.5, NO2, SO2, and VOCs) and its association with airway inflammation (FeNO) among primary school children in industrial and non- industrial areas in Kemaman, Terengganu. A cross-sectional comparative study was conducted among Malay primary school children in Kemaman, Terengganu. A validated questionnaire was randomly distributed to children to get the background information, respiratory symptoms and exposure history of the children. The assessment of indoor air quality was carried out in each primary school and home using indoor air monitoring equipment. Fractional exhaled nitric oxide (FeNO) was measured using an NIOX MINO device. The results showed a significant difference between concentrations of PM10, PM2.5, NO2, SO2, and VOCs in different classrooms from selected schools and homes of exposed and comparative groups, P<0.05. Statistical analysis revealed that the FeNO level was significantly higher among the exposed group compared to the comparative group (Z= -9.442, p= 0.001). The research suggests that the exposure to industrial air pollutants will increase the risk of getting respiratory inflammation among primary school children living near industrial areas.
This study compares the distribution of dissolved nutrients (NO3âˆ’ and PO43âˆ’) between two seasons (pre-monsoon and post-monsoon) in Pulau Perhentian, Terengganu. The concentration of dissolved PO43âˆ’ was found to be 16 to 83 times higher during the post-monsoon period (April 2015) compared to the pre-monsoon period (October 2014). On the other hand, the concentration of dissolved NO3âˆ’ was two (2) to three (3) times higher during the post-monsoon period (April 2015) compared to the pre-monsoon period (October 2014). These nutrients' inputs were converted from P limitation condition during the pre-monsoon period to N limitation condition during the post-monsoon period at our study area. The results of this study suggest that the Northeast monsoon plays an important role in influencing the distribution of dissolved nutrients between seasons in Pulau Perhentian. It is thought that during the post-monsoon period, a considerable input of nutrients from bottom water is responsible for increasing dissolved nutrients in surface water, in particular PO43âˆ’.
Clinacanthus nutans, known to the locals as Belalai Gajah, is a medicinal plant widely used by Malaysians in the belief to cure various diseases including cancer. However, the production of Belalai Gajah hardly fulfils the market demand since the growing techniques of stem cutting and tissue culture are inefficient and expensive. Therefore, improvements in tissue culture techniques and materials application are required. Hence, this study tested Carica papaya (locally know as papaya) stem, an agricultural waste, to enhance the tissue culture of C. nutans. The effects of C. papaya stem powder and extract on the shoot proliferation of C. nutans parameters were investigated. The average number of shoot, leaves and length of leaves were observed. Phytochemicals screening was also conducted. Overall, C. papaya stem extract showed positive performance and 1% extract was found to be the optimum concentration to enhance the shoot proliferation. Meanwhile, C. papaya stem powder inhibited the shoot proliferation. It was also found that flavonoids, glycosides, steroid and terpenoid contributed in the shoot proliferation. In conclusion, the papaya stem extract is a potential in-vitro supplement for tissue culture studies. This study gained insights in sustainable green economy and showed that zero waste can be attained by converting local papaya stem waste to valuable product. In addition, sustainable technology in pharmaceutical approach could be addressed through in-vitro low cost large-scale production of Belalai Gajah medicinal plant.
Solid waste management in developing countries including Malaysia is dominated by waste dumpsites which have a high possibility of transporting organic and inorganic pollutants to the underlying groundwater and surface water within the surrounding area. The objective of this study is to characterise the landfill leachates and its surrounding groundwater and river water quality and metals concentrations, namely arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb) and zinc (Zn) from Beris Lalang, Kelantan. Nine sampling points were collected within the dumpsite for analysis of in-situ: dissolved oxygen (DO), pH, total dissolved solids (TDS), conductivity, turbidity and ex-situ; Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD) and Suspended Solids (SS) and the results were compared with permissible limits. As and Pb in groundwater samples were collected from the surface of two dug grounds within the vicinity of the dumpsites exceeded the standard of Ministry of Health. Cr, Cu and Pb in leachates exceeded Environmental Quality Act (EQA, 1974)'s standard, whereas Ni, Pb and Zn in surface water of Gali River exceeded the limit of class III National Water Quality Standard (NWQS). Exceeding metals concentration in leachates and its surrounding groundwater and river water relative to their respective standards points out toward potential leachate migration to the waterbodies within the surrounding vicinity of Beris Lalang dumpsite. This study provides the initial baseline data and preliminary monitoring assessments as a first step towards improving water security and waste management in Kelantan.
Serious agriculture - related accidents are increasing and tractor overturning is one of the most important factors leading to death in farms in Iran. In fact, the interplays between tractor operator and environment cause such damages. There are several reasons involved in tractors overturn that the recent method in tractor design is nearly to improve with using the electronics instrumentation that gives the operator key guides related to the tractor`s stability as it is operated. In this study a new system was developed. To measure a steep slope land electromagnetic gauge was constructed. The working principles of the slope gauge, based on the magnetic field were changed by changing the slope of the ground. The embedded inclinometer within the pendulum inclinometers with their period are used to altering the magnetic field. The output of inclinometer analog and the voltage range was (47/2-32/0) V. This information was then processed by a microprocessor, and an assessment of rollover potential was reported to the display device.
In order to ensure the optimum quality of palm oil, oil palm fruit needs to be harvested at the optimum maturity to avoid free fatty acid (FFA) accumulation. The high content of FFA not only reduces the quality of palm oil but also increases the refining cost. Optimum maturity based on plantation standard operating procedure (SOP) is determined by identifying the tree with loose fruit on the ground. The matured bunch is further identified based on the colour of the bunch. This paper presents a research work on formulation and validation of mathematical equations to estimate the maturity stages (age in weeks) of fresh fruit bunch (FFB) based on FFB position in oil palm phyllotaxis (spiral leaves arrangement) as an additional feature to confirm the maturity level of oil palm FFB. Regression analysis showed that the proposed method was able to estimate the maturity stages of oil palm FFB with the coefficient of determination R2 = 0.9 and a root mean square error (RMSE) of 1.58 weeks. The FFB yield estimation model and harvesting can be created based on the extracted data using the formula which will help in the planning of harvesting operation. Plantation manager can use this information to generate yield variability map and estimate the appropriate number of workers and machine. Planned harvesting operation can save a significant amount of time in site harvesting operation.
Carbamates are poisonous pesticides which have been used widely in agriculture production for decades. Unlike other pesticides such as organophosphate, carbamate pesticides are not persistent in the environment however, their degradation is crucial due to their toxicity to living system. The World Health Organization, categorized carbamate pesticide as toxic, hazardous and restricted for use. Example of carbamates pesticides include Carbaryl, Aldicarb, Methomyl, Carbofuran, and Propoxur. They are extensively used to control many insect and pests of crops. Presently, there is significant awareness regarding the negative effects of pesticides due to their ability to pollute soil and water bodies. Most pesticides are readily degraded or metabolized by microbes. Carbamate pesticide degradation by microorganisms relies not only on the availability of microbes with suitable biodegradative enzymes, but also on the various ecological factors. This review-article outlines the present development in biodegradation of carbamate pesticides, their toxicity and enzymatic degradation as well as their degradative pathways.
In this study, for 5.1 million bee colonies and nearly 42 thousand migratory beekeepers in Turkey, an information system is recommended that determines the areas where the honey season will pass taking into account the flowering periods of plants. Migratory beekeepers produce honey by following the flowering periods of nectar sources. Bee colonies should be placed in the optimum number in areas with nectar sources. Less colony settlement has a negative impact on agricultural production. Colony condensation also adversely affects the honey yield of bee colonies per hive. In this study focuses on the optimal number of colonies in the nectar region. In the first stage, 81 provinces in Turkey were analyzed in terms of nectar resources and meteorological conditions which are the major sources of honey production. This evaluation used fuzzy cognitive maps. As a result of the evaluation, 33 provinces were identified as the most suitable provinces in terms of nectar sources and meteorological conditions. In the second phase of the study, a new approach has been proposed for migratory beekeepers to pass the nectar flow season at maximum efficiency and to use nectar resources at maximum level. This approach is based on the placement of bee colonies, considering the potential of the bee farming of the regions and the number of bee colonies subjected to migratory beekeeping. One of the advantages of this approach is that it will maximize honey yield per colony for migratory beekeepers. Another advantage of this system is that the distribution of bee colonies according to the number of plants in the region will be positive in terms of quality and quantity of agricultural production.
Fuzzy cognitive maps, information system, migratory beekeeping, nectar flow
This study was conducted to evaluate the physical habitat of spawning areas for Thynnicthys thynnoides (T. thynnoides) in the Rui River, Gerik, Perak. Five sampling sites of Rui River's floodplain were chosen. Sampling was conducted between May and October 2015 by using a visual-based habitat assessment developed for Rapid Bioassessment Protocols for Use in Streams and Wadeable Rivers: Periphyton, Benthic Macroinvertebrates and Fish. This study showed that T. thynnoides still migrated to the upper stream of Rui River during spawning season mainly in August. Habitat assessment scoring indicated that the physical habitat structure of Rui River fell into a suboptimal category, which was most likely able to support fish populations and thus providing a suitable habitat for T. thynnoides during the spawning season. Conclusively, it was observed that the T. thynnoides population was dependent on environmental conditions.
Fisheries, habitat, riverine, Rui River, spawning, Thynnichthys thynnoides
Events are the most important bits of information that should be delivered timely wherever the person is. It is but equally important that a person must have the ability to keep abreast with the recent trends of technology in order to be notified of the important events that need to be addressed or responded immediately. Sometimes, notification of events is given in a short period of time, which sometimes leads to failure in attending or responding such events. In today's generation, smartphones are always and almost available to every individual, with which one of its most important features is notification. It is under this premise that prompted the researchers to develop an Android-based ubiquitous notification app for Bukidnon State University (BukSU) to speed up the dissemination of information about the upcoming events and activities of the university. The University Administrators will act as an admin in order to input and update the list of activities or events for the entire academic year which is either planned, unplanned, routine or emergency in nature. The faculty, staff, students and other stakeholders will act as a user and will be notified of the academic activities. A Waterfall Model was used in the design process and Android studio in the development of the application. As a result, the system was tested in terms of its functionality, applicability, relevance, and usability. The overall result has a mean of 4.736 which indicates that the respondents are very satisfied with the mobile application. A ubiquitous notification app is currently being utilized by the Bukidnon State University Administrators in order to notify the students, faculty, staff, and alumni in notifying them of the event before it takes place.
Android app for notification, Bukidnon State University Notification App, BukSU Notification App, information system, mobile apps, notification app, notification system, Ubiquitous Notification App
A new approach for speaker and accent recognition based on wavelets, namely Discrete Wavelet Packet (DWPT), Dual Tree Complex Wavelet Packet Transform (DT- CWPT) and Wavelet Packet Transform (WPT) based non-linear features are investigated. The results are compared with conventional MFCC and LPC features. k-Nearest Neighbors (k-NN), Support Vector Machine (SVM) and Extreme Learning Machine (ELM) classifier are used to quantify the speaker and accent recognition rate. The database for the research was developed using English digits (0~9) and Malay words. The highest accuracy for speaker recognition obtained is 93.54% while for accent recognition; it is 95.86% using Malay words. Combination of features for speaker recognition is obtained from ELM classifier is 98.68 % and for accent recognition is 98.75 % using Malay words.
In this paper, we present a novel multi stego-image based data hiding method using the principle of the modified least significant bit (LSB) matching to improve the embedding capacity (EC) as well as image quality. Initially, each original pixel produces four new pixels. The secret data is hidden in all the four produced pixels. Then the pixels are readjusted to improve the quality of the stego-images. There are four separate stego-images developed from the four different readjusted pixels. Each stego-image hides one bit per pixel. The average peak signal-to-noise ratios (PSNR) for the stego-images are 36.06 dB, 37.88 dB, 39.60 dB and 41.00 dB respectively. Furthermore, the proposed method successfully withstand against RS-steganalysis.
Data hiding, LSB Matching, RS-analysis, steganography
Combining non-binary LDPC (Low-Density Parity-Check) codes and high order constellations, such as Quadrature Amplitude Modulations (QAM), is an effective way to improve the bandwidth efficiency. Since, the message exchanged in the LDPC decoder can be measured by the APP (A Priori Probability) or the LLR (Log-Likelihood Ratio), depending on the decoding algorithm type, the message at the decoder input that computed by the QAM must be using the same calculation. However, the number of operations performed by the QAM increases with the constellation order, and the calculation changes with the channel type. In this paper, we use simplified LLR computations, introduced for binary codes, to simplify the APP calculation of square-QAM-Gray demapping for APP-based non-binary LDPC decoders. Under Gaussian channel, the simplified APP calculation achieves the same performance that obtained with the exact APP computation. The same simplified APP calculation used for a Gaussian channel can be applied, with minor operations added, for Rayleigh channel, and it shows a small performance loss with respect to the exact APP computation. These simplifications simplify the combination of non-binary LDPC codes with QAM. With this method, it is easy to change a decoding algorithm based on the APP to an algorithm based on the LLR.
A Priori Probability (APP), Log-Likelihood Ratio (LLR), Non-Binary LDPC code, Square-QAM-Gray mapping
Eyeblinks are having the significance to analyze the attention, fatigue, behaviour and emotion of an individual. Eyeblink recognition is adopted by many medical and surveillance applications to identify the person's state. The eye blink recognition on videos requires tracking the eye region and to count the number of eye blinks. In this paper, a three-stage model is presented to detect the eye blinks accurately. In the first stage, the frame similarity analysis, background separation, positional and mathematical filters are applied collectively to identify the effective eye region on unique frames. In the second stage, the similarity analysis using wavelet decomposition and statistical filters are applied on the segmented eye region. The filtered evaluation is performed to identify the change on the eye region of continuous segmented frames. At the final stage, distance driven map on structural and statistical features is applied to remove the invalid frame changes and to obtain the accurate eye blink count. The proposed model is applied on real time, web-collected and the NRC-IIT dataset videos. These complex videos are associated to the indoor and outdoor environments. The news reading and other complex video sequences are analyzed in this research. The observations identified that the proposed model has reduced the possible generated errors and provided the accurate detection of eye blinks.
Eyeblinks, statistical, structural, video sequences
The functional data model has recently received increasing attention particularly in their application to mortality forecasting. The advantage of this method over the well-known Lee-Carter model is the ability to treat the underlying process as functional, and provide estimations that are robust to outliers. This research investigates the accuracy of functional data approach in estimating the mortality rates and life expectancy at births in developing countries including Malaysia, Indonesia, Thailand and Singapore. The functional data method was applied to these countries' mortality data, and the out-sample forecast errors showed that, in terms of overall, the functional data model was more accurate than that of the original Lee-Carter model for males and females. The results provide evidence that the functional model is accurate to forecast the life expectancy at births for developing countries.
Functional data model, Lee-Carter model, life expectancy at births, mortality forecasts
In the field of data analysis, clustering is an unsupervised technique that can be used to find identical sets of data. But, it is tough task to find the optimal centroid for a given dataset, especially in hard clustering problems. Recently, a vibrating particle system (VPS) algorithm was developed for solving the optimization problems. This algorithm is based on the concept of free vibration and forced vibration. This algorithm provides more effective and optimal solutions for constrained optimization problems. In this work, the performance of VPS algorithm is evaluated for solving hard clustering problems. The objective of this algorithm is to compute optimal centroid for hard clustering problems. The efficiency of the proposed algorithm is measured on well known clustering datasets and compared with some popular clustering algorithms. The simulation results demonstrate that the VPS algorithm obtains effective results as compared to other algorithms.
Clustering, K-means, meta-heuristic algorithm, vibrating particle system
This paper presents texture feature extraction scheme with the help of extended version of Fuzzy local binary pattern (FLBP) to get more efficient feature from the input image. The proposed scheme extends (FLBP) technique employing Intuitionistic fuzzy set and it is known as Intuitionistic fuzzy local binary pattern (IFLBP). Moreover, IFLBP provides additional bin in the distribution of IFLBP values. Additionally, it can be used as the feature vector of the image and can be apply in diverse fields of image processing. The proposed algorithm has used various medical as well as image processing images of different sizes for result analysis. It clearly shows that the obtained results are better than the existing techniques and its extracted feature are more informative than the reported methods.
Entropy, fuzzy local binary pattern, feature extraction, intuitionistic fuzzy local binary pattern, histogram, intuitionistic fuzzy sets
This study was conducted to determine the baseline water quality characteristics of a contaminated NAHRIM lake undergoing remediation by the constructed wetlands, based on the physico-chemical and biological parameters. The sampling was conducted for six months (May-October) in 2016 from 5 stations of the lake and analysed using APHA standard methods for water and wastewater analysis, while Malaysian water quality index (WQI) was used to calculate quality of the lake. The results showed that, the Conductivity, Dissolved Oxygen, NO3-N, NO2-N, PO4, Temperature, Turbidity, TDS, TSS, and Zn were under class I, while pH, B and COD were categorized under class II. NH3-N, BOD, Fe, Escherichia coli, Total coliform and Mn were categorized as class III. Moreover, Al was not given any classification under NWQS but their concentration did not exceed EPA guidelines. Furthermore, as compared to the water samples from the constructed wetlands that reported a class III WQI, the lake was observed to show an overall class II WQI. This is suggestive of the retaining and remedial role of the constructed wetlands being the first point of contact for the contaminants going to the lake. Thus the lake is suitable for recreational activities.
Biological and physicochemical parameters, constructed wetlands, lake, water quality
This study aims to develop a side-sensitive modified group runs control chart using auxiliary information (SSMGR-AI) to enhance the speed of detecting mean shifts in a process. The average run length (ARL) and expected average run length (EARL) criteria are adopted as performance measures of the proposed chart. The performance of the proposed chart is compared to the exponentially weighted moving average chart with AI (EWMA-AI) and the run sum chart with AI (RS-AI), in terms of the ARL and EARL criteria. The results reveal that the optimal SSMGR-AI chart generally outperforms all charts under comparison for detecting shifts in the process mean. An application with numerical data is presented to elaborate the implementation of the SSMGR-AI chart.
Auxiliary information (AI), average run length (ARL), expected average run length (EARL), side-sensitivity, side-sensitive modified group runs (SSMGR)
Timber is one of the most sustainable and renewable raw materials available. Globally, it has been increasingly used for the manufacture of home and workplace furniture. Timber products are known to have ignition resistance and a low heat release rate. These characteristics delay burning and maintain the structural durability of a product, protecting both the occupants and their properties in a fire. Timber, however, experiences thermal degradation during combustion, yielding smoke, heat, toxic gases, and char when burned. To understand the fire conduct of timber, extensive knowledge in its process of decomposition is essential. This paper, therefore, reviewed the methods of flammability tests widely employed to investigate the reaction of timber and timber-based product to fire, namely cone calorimeter test, room-corner test, limiting oxygen index (LOI) test, furnace test, and single burning item test (SBI). In addition, an overview of the fire retardant treatments; impregnation and coatings was also presented. The potential effects of fire retardants on the durability, strength, hygroscopicity, corrosion, machinability, glueing characteristics, and paintability of the timber were also highlighted.
The purpose of this research is to analyse the influence of change management and e-learning in Malaysian private higher education institutions focusing on educators' perspectives. The conceptual framework was modified in combination of various theories from Systemic Change Models and E-learning Cycle Models. A self-administered questionnaire adapted from Siebel 4.0-2 Survey Questionnaires (SSQ) by Hambling, 2010 was the data collection instrument. The sample consisted of educators from private higher education institutions with visions or missions based on e-learning implementation in Malaysia. As per findings, through review of the visions and missions, the selected private higher education institutions integrated teaching and learning with Stepwise Multiple regression analysis, has a significant relationship on independent variables that contribute to e-learning implementation.
Execution of the green building project specifically among the housing developers in Malaysia is still at its infancy. As of August 2016, there are only 16 housing projects certified by the Green Building Index (GBI) under the category of Residential New Construction (RNC) since the assessment systems established in 2010. The authors address this issue in the context of the factors affecting the execution of the green building project among the housing developers in Klang Valley. A pilot study by using questionnaire survey was conducted among 30 housing developers from 10 different zones divided by the Ministry of Housing and Local Government, Malaysia. This paper aimed to report the results of the reliability test of the designed questionnaire. The results based on the Cronbach's Alpha analysis showed that the items used in the questionnaire were reliable and obtained an acceptable level of internal consistency, which were relevant for the main study. The pilot study revealed that only 9 out of 30 respondents had the completed or ongoing green building projects. The findings exposed the level of knowledge, emotion, value, attitude, behavior and the potential factors affecting the execution of the green building projects among the housing developers in Klang Valley.
Execution, green building, housing developers, Malaysia
The objective of this study was to determine the prevalence of symptoms and problems in Malaysian brain pathology patients. A total of 100 respondents in Kuala Lumpur Hospital were included in this cross-sectional study. The study utilized European Organization for Research and Treatment of Cancer Quality Of Life questionnaire (EORTC QLQ-C30). Patient with a "symptom/problem" having the minimum response of "a little". A response of "quite a bit" was defined as having a "severe symptom/problem". The two most prevalent "symptoms/problems" among the neurological disorder patients were fatigue (65%; severe: 28%) and reduced cognitive functioning (64%; severe: 25%). The mean number of "symptoms/problems" ranged from 4.63 (meningioma) to 6.80 (cerebellar edema) while the mean number of "severe symptoms/problems" ranged from 1.39 (astrocytic glioma) to 2.8 (cerebellar edema). Therefore special attention should be given to these patients in order to improve the overall quality of life of the patients.
Brain pathology, neurological disorder, quality of life, severity, symptomatology
The research in this paper discusses about the development and validation of a novel, cost effective, simple, reproducible and accurate UV-spectrophotometric method to estimate naratriptan hydrochloride in bulk as well as pharmaceutical formulations. Naratriptan hydrochloride was analyzed at 223 nm in simulated saliva (pH 6.8) and phosphate buffer (pH 7.4). Linearity was present in the concentration range of 1-40 µg/ml for both media. The method was validated as per different parameters according to International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use (ICH) guidelines of Q2 (R1). The suggested method was successfully used for the analysis of naratriptan hydrochloride in-house oral film formulation as linearity values for the same were found to be 1-40µg/mL. The results revealed the suitability of the technique for the estimation of naratriptan hydrochloride in the oral films for its accuracy, precision, and reproducibility.
Bisphenol A (BPA) is an endocrine disrupting chemical (EDC) widely used in industry as a plasticizer for the production of polycarbonate plastics and epoxy resins. The liver is highly sensitive to BPA, even at low doses. The objective of the study is to investigate the effect of BPA on histo-architecture of the liver in post-weaning rats. Post-weaning female rats were exposed to BPA by oral gavage over a six weeks period. The results showed that even at low environmental doses, BPA exposure had adverse effects on the liver histo-architecture, thereby disrupting the functions of cellular. The administration of BPA resulted in severe hepatocytes necrosis, dilated sinusoid, and depicting features of conspicuous Kupffer cells. The results may be due to the generation of reactive oxygen species (ROS) by BPA. In conclusion, post-weaning exposure of BPA resulted in significant histological alterations due to ROS generation.
Bisphenol A, histology, liver, oxidative stress, plastic
The ocean has an exceptional resource with various groups of natural products that are potentially useful for biomedical and other applications. Marine sponges have prominent characteristic natural products with high diversity. They produce many vital therapeutic metabolites with prominent biological activities. Marine invertebrates and microbial communities are the primary producers of such metabolites. Among the richest sources of these metabolites, class Demospongiae and the order Haplosclerida and genus Xestopongiae from family Petrosiidae are of interest. This review summarizes the research that has been conducted on two classes, eight orders, twelve families and fourteen genera of marine sponges available in the South East Asia region, covering the literature of the last 20 years. Ninety-five metabolites including alkaloids, sterols, terpenoids, quinones isolated from marine sponges collected in South East Asia along with their bioactivities especially cytotoxicity and antibacterial activities were reported in this review. Chemistry and biology are highly involved in studying marine sponges. Thus, tight collaboration is needed for understanding their taxonomy aspects. This review will outline chemistry and biological aspects, challenge, limitation, new idea and a clear future perspective on the discovery of new drugs from South East Asia's marine sponges.
Bioactivities, chemistry, marine sponges, South East Asia
Centella asiatica or known as 'pegaga' in Malaysia, is a popular medicinal herb, which is being used as main ingredient or incorporated into various herbal products. Apart from efficacy, the chemical profile and potential toxic effect of the plant are two important aspects of concern towards ensuring product satisfaction and safety of consumers. This paper reports the qualitative and quantitative chemical analysis of the leaf ethanolic extract of C. asiatica using LCMS/MS. The acute toxiciy effect of the extract and selected marker chemical constituents were further analysed using a zebrafish model. Twenty constituents, were identified and the main chemical marker constituents of the plant viz asiaticoside, asiatic acid, and madecassic acid were further quantified. Asiaticoside was found to be present in higher concentration than the other marker constituents. Meanwhile in the acute toxicity test, the LD50 of the extract on the zebrafish model was determined to be 1250 mg/L while 100% mortality was observed at the highest test concentration of 2500 mg/L. However, acute toxicity evaluation on four marker triterpenoids of the herb, i.e asiatic acid, madecassic acid, asiaticoside and madecassoside, indicated them to be quite safe on the zebrafish model, with no mortality shown for test concentrations between 10 to 500 mg/kg BW.
Acute toxicity, Centella asiatica, HPLC-DAD-LCMS/MS, metabolite profile, zebrafish model
Waste rocks are a non-economical by-product of mining operations, which can lock up carbon dioxide into a carbonate form and thereby help reduce greenhouse gases emissions. The aims of this research are to determine the mineral and chemical composition of the sedimentary waste rocks of gold mines and to classify the potential of silicate minerals to be a feedstock for carbonation mineralization. The sampling was undertaken at the Selinsing gold mine, where waste rocks were collected from the waste dump, stockpiles, the borrow pit, and the main pit. The mineralogical and chemical component of the sedimentary waste rocks were explored using X-ray diffraction and energy dispersive X-ray spectroscopy. The findings indicated that the presence of divalent cations, of 55.12% for CaO, 9.09% for MgO, and 16.24% for Fe2O3 from gold mine waste, capable of sequestering carbon dioxide into calcium, magnesium and iron carbonates, respectively, through carbonation of mineral. The domination of silicate minerals such as quartz, muscovite, kaolinite, chlorite, albite, and carbonate minerals such as calcite, have been found to be widespread in sedimentary waste rocks. However, the natural silicates (chlorite, muscovite) and carbonates (calcite) are potential minerals which can be consumed as feedstock for carbonation processes because they contain the magnesium, iron, and calcium elements which can form stable carbonates in the presence of carbon dioxide. The mineralogy and chemical composition of sedimentary waste rocks from the Selinsing gold mine provides a better understanding of the future carbonation reaction to sequester more carbon dioxide in response to climate change.
Carbonation reaction, carbon sequestration, chemical composition, mineralogy, sedimentary rock, Selinsing gold mine
Bone defects are serious complications that are caused by extensive trauma or tumor. The traditional therapies fail to repair these defects. Tissue engineering scaffold can be used to regenerate the damaged tissue. This paper describes an experimental investigation of bone scaffold to measure the porosity using gas porosimeter and suggest an alternative to bone scaffold. The prototype was made using additive manufacturing of selective laser sintering technique. The material chosen for the study was synthetic polymer PA12. The behaviour of actual bone and prototype had been observed under compressive load of fixed interval loading condition. Mechanical properties of polymer had been evolved and compared with actual bone.
Field surveys of the 2011 Tohoku Tsunami reported massive failures of many seawalls and coastal barriers. The massive damages are vivid evidence that there are flaws in the design of seawalls and barriers. With this as the background, a sequence of laboratory experiments using dam-break waves was performed to simulate the interactions between the tsunami-like bore flow and vertical seawall as well as to measure the bore-induced pressures and to estimate forces exerted on the vertical seawall model. The experimental result revealed that the maximum pressure (approximately 8 kPa) exerted on the vertical seawall was measured at the lowest pressure sensor location. Experimental data were used to re-examine the relevant empirical formulae found in the literature. The obtained results could be useful for calibrating mathematical and numerical models as well as for future research concerning the design of tsunami barriers.