72 research outputs found

    Impact of elevated CO2 on leaf gas exchange, carbohydrates and secondary metabolites accumulation in Labisia pumila benth

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    Aims: The aim of this study was to investigate different levels of CO 2 availability alters total phenolic and flavonoid, total available carbohydrate (TAC) and to determine how elevated CO 2 influences gas exchange of Labisia pumila seedlings. Study Design: The 3-months Labisia pumila seedlings of var Alata, var Pumila and var Lanceolata were put under 1 month to acclimatize in a nursery until ready for the treatment. Carbon dioxide enrichment treatments started when seedlings reached 4 months old by exposing them to three levels of CO 2 , viz., ambient CO 2 (400 µmol/mol), twice ambient (800 µmol/mol) and thrice ambient CO 2 (1200 µmol/mol). The split plot 3 x 3 factorial experiment was designed using randomized complete block design with CO 2 levels being the main plot and varieties as the sub-plot replicated Original Research Article Ibrahim et al.; ARRB, 19(6): 1-16, 2017; Article no.ARRB.36673 2 three times. Place and Duration of Study: Ladang 2, Universiti Putra Malaysia Glasshouse complex between July to November 2011. Methodology: The experiment was conducted for 15 weeks. The measurement of photosynthesis was obtained from a closed infra-red gas analyzer LICOR 6400XT Portable Photosynthesis System (IRGA, Licor Inc., USA). Total phenolics and flavonoid were determined using Follin-Ciocalteau reagent and total available carbohydrate using anthrone reagent. Results: It was found that the treatment effects were contributed by CO 2 levels in all weeks measured in leaf gas exchange properties (Net photosynthesis (A), stomatal conductance (g s), transpiration rate (E), intercellular CO 2 (C i) and Instantaneous water use efficiency, WUE). A combination of increases rates of A and E was responsible for enhancement of WUE by 50% in elevated treatment (800 and 1200 µmol/mol). Total available carbohydrate, total phenolics and flavonoid were also influenced by elevated CO 2 in all weeks of measurement. At end of 15 weeks after treatment (WAT), 44% increase in total available carbohydrate had increased total phenolic and flavonoid by 56% and 149% respectively than ambient treatment. At end of 15 WAT It was found, that the photosynthetic capacity of Labisia pumila was enhanced under elevated CO 2 by significantly have higher maximum electron transfer rate, J max and Rubisco CO 2 fixation capacity V cmax than ambient seedlings. Conclusion: In this work, it was observed that the increase in production of total phenolics and flavonoid in L. pumila might be due to increase in production of total available carbohydrate in the present study. The upregulation of photosynthesis in the present study was supported by enhancement of Maximum electron transfer rate, J max and Rubisco CO 2 fixation capacity V cmax than ambient seedlings that showed this plant has high sink strength to cope with high level of CO 2

    The prediction of suspended solids of river in forested catchment using artificial neural network

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    This study presents an artificial neural network (ANN) model that is able to predict suspended solids concentrations in forested catchment namely Berring River, Kelantan, Malaysia.The network was trained using data collected during a period of 13 days in April 2001. The sampling location was established in the middle section of the river for collecting water samples. The study was carried out for a duration of two weeks in April 2001. The water sample was collected at 60% of the total depth from the river bed for every two hours starting from 6:00 am to 12:00 midnight for the whole duration of the study period. In this study five parameters were selected as input parameter for the network which are turbidity, flow velocity, depth, width, and weather condition of during the sampling period, while suspended solids as desire output. The data fed to the neural network were divided into two set: a training set and testing set. 116 of the data were used in training set and 24 remained as testing set. A network of the model was detected automatically by the network to give good predictions for both training and testing data set. A partitioning method of the connection weights of the network was used to study the relative percentage contribution of each of the input variables. It was found that turbidity and river width gives 73.03% and 24.73% each. The performance of the neural network model was measured by computing the correlation coefficient which gives the value of 0.93. It’s shown that the neural network gives superior predictions. Based on the results of this study, ANN modeling appears to be a promising technique for the prediction of suspended solids. Dynamic Metadata(s

    Trace determination of cadmium content in Malaysian herbs using graphene–ionic liquid-modified screen-printed carbon electrodes

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    A simple and effective method of square-wave anodic stripping voltammetry (SWASV) with screen-printed carbon electrodes (SPCEs) was used to determine the cadmium concentration in Malaysian herb samples. The optimization process involved the selection of an optimized pH, an acetate buffer as a supporting electrolyte, the deposition potential, deposition time and the surface modification process on an SPCE surface. The optimum conditions were a pH of 4.5, a deposition potential of −1.4&thinsp;V and a deposition time of 120&thinsp;s. The SPCE surface was modified with the fabrication of the graphene–ionic liquid composite as the sensing layer. Four herb samples were tested, where herbs A, D, M and C contained 0.0035, 0.0237, 0.0267 and 0.0251&thinsp;ppm of cadmium, respectively. The sensitivity of the proposed sensor was compared with an inductively coupled plasma–optical emission spectroscopy (ICP–OES). The relative standard deviation (RSD) between the sensor and the ICP–OES indicated that the sensor was sensitive, as RSD was below 20&thinsp;% with range of 7.93&thinsp;% to 18.28&thinsp;%.</p

    Threshold Voltage and Leakage Current Variability on Process Parameter in a 22 nm PMOS device

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    This article explains the effect of variation on the process parameters while designing a Nano-scaled planar PMOS device in complementary metal-oxide-semiconductor (CMOS) technology for 22 nm gate length. This procedure aims to meet the best combination of fabrication process parameter on the threshold voltage (VTH) and leakage current (IOFF) which was predicted by the International Technology Roadmap for Semiconductors (ITRS). The gate structure of the PMOS device consists of Titanium Dioxide (TiO2) as the high permittivity material (high-k) dielectric and Tungsten Silicide (WSix) metal gate where it is deposited on top of the TiO2 high-k layer. The simulation process was designed using an industrial-based numerical simulator. This simulator was then aided in design with the L9 Taguchi’s orthogonal array method to optimise the best combination of process parameters in order to achieve the optimum VTH value with the lowest IOFF. The analysis results of the factor effect on the SNR in ANOVA analysis clearly show that the Halo implantation tilting angle has the greatest influence with 52.47% in optimising the process parameter where the implantation tilting angle is at 35°. The final results in characterizing and modelling the process parameters of the 22 nm PMOS device with reference to the prediction ITRS succeeded where the result of the VTH is 4.25% closest to the prediction value of -0.289 V ± 12.7% and minimum IOFF value which is 92% away from the predicted value which is 100 nA/µm

    Overview of machine vision on digital imaging approach for automatic tuna length measurement

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    The demand of fish and marine product have increased significantly throughout the year. Therefore, overfishing had become major concern for various parties around the world especially the United Nation(UN). Collecting numerical data is a first step toward preservation and conservation of tuna and other fish population. This paper reviews automatic tuna length measurement by using machine vision techniques. This is one of the steps in collecting necessary data on size of fishes caught by fishermen. Previous research had been done on measuring the length of fish, but the accuracy rate of the length measurement is not satisfactory enough. Many factors affecting the accuracy of the length measurement processes such as lighting inequalities, blood on the platform and others. Machine vision techniques have a great potential to be used in automating the measurement of the fish length with high accuracy. Machine vision techniques could improve the accuracy and efficiency of the measurement of the fish length that would substitute the tedious manual work

    Implementation of Particle Filtering in TDOA Positioning

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    This paper describes the implementation of particle filtering (PF) estimation method in TDOA positioning to mitigate the effect of NLOS signal propagation on the TDOA measurements. The measurement errors were modelled according to the circular disk scatter model (CDSM) ranging from 0 to 600 m. In this paper, we consider static PF which uses one TDOA measurement to estimate one fixed MT position. The network layout is set up with five base stations (BS) that resolve to a total of ten measured TDOAs in every PF iteration. The performance of the static PF was compared to two basic estimation methods namely robust intersection estimation (RIE) and linear least square (LLS). The simulation results show the stability of static PF over a wide range of measurement errors and giving an almost constant estimation error at various CDSM radiuses. Static PF outperforms RIE and LLS with the estimation error of less than 40 m and 60 m for 67% and 90% of the time respectively

    Control Factors Optimization on Threshold Voltage and Leakage Current in 22 nm NMOS Transistor Using Taguchi Method

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    In this article, Taguchi method was used to optimize the control factor in obtaining the optimal value which is also known as response characteristics, where the threshold voltage (Vth) and leakage current (Ileak) for NMOS transistor with a gate length of 22 nm is taken into account. The NMOS transistor design includes a high permittivity material (high-k) as a dielectric layer and a metal gate which is Titanium Dioxide (TiO2) and Tungsten Silicide (WSiX) respectively. The control factor was optimized in designing the NMOS device using the Taguchi Orthogonal Array Method where the Signal-to-Noise Ratio (SNR) analysis uses the Nominal-the-Best (NTB) SNR for Vth, while for Ileak analysis, a Smaller-the-Better (STB) SNR was used. Four manufacturing control factors and two noise factor are used to optimize the response characteristics and find the best combination of design parameters. The results show that the Halo implantation tilting angle is the dominant factor where it has the greatest factor effect on the SNR of the Ileak with 55.52%. It is also shown that the values of Vth have the least variance and the mean value can be set to 0.289 V ± 12.7% and Ileak is less than 100 nA/µm which is in line with the projections made by the International Technology Roadmap for Semiconductors (ITRS)

    Review: Identification of roadmap of fourth construction industrial revolution

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    Industrial revolution is a series of events driven by the growth of technological innovations, and so far, the world had witnessed the first three industrial revolutions. Today, a new revolution referred to as the fourth industrial revolution is entering even though it is still in its early stages of development. Many developed countries had established their own roadmap or strategic plan as a first step. However, only a few of them touched the construction sector even though the construction industry provides a significant contribution to the country’s GDP. Based on this understanding, there is a fundamental need to give a clear view of Industry 3.0 to Industry 4.0 from the construction industry’s perspective, since most users are still finding their way in this transition. An extensive literature review is used to define the scope and terms of the field of construction in the industrial revolution. Towards this goal, a clear definition and concept of each revolution, key technologies related to construction and challenges faced by the industry will be explored. Simultaneously, this review paper also benchmarked a few documents as a simple guide in the transition process to the fourth industrial revolution to avoid a lag in a world where changes are swift and sudden. Therefore, this review paper contributes by providing a better understanding of the challenges and trends in Construction 4.0 to academics and practitioners. Moreover, it will spark new ideas on the policy or strategic roadmap development in the future

    The molecular phylogenetic signature of Bali cattle revealed by maternal and paternal markers

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    Bali cattle is a domestic cattle breed that can be found in Malaysia. It is a domestic cattle that was purely derived from a domestication event in Banteng (Bos javanicus) around 3,500 BC in Indonesia. This research was conducted to portray the phylogenetic relationships of the Bali cattle with other cattle species in Malaysia based on maternal and paternal lineage. We analyzed the cytochrome c oxidase I (COI) mitochondrial gene and SRY of Y chromosome obtained from five species of the Bos genus (B. javanicus, Bos gaurus, Bos indicus, Bos taurus, and Bos grunniens). The water buffalo (Bubalus bubalis) was used as an outgroup. The phylogenetic relationships were observed by employing several algorithms: Neighbor-Joining (PAUP version 4.0), Maximum parsimony (PAUP version 4.0) and Bayesian inference (MrBayes 3.1). Results from the maternal data showed that the Bali cattle formed a monophyletic clade, and together with the B. gaurus clade formed a wild cattle clade. Results were supported by high bootstrap and posterior probability values together with genetic distance data. For the paternal lineage, the sequence variation is low (with parsimony informative characters: 2/660) resulting an unresolved Neighbor-Joining tree. However, Bali cattle and other domestic cattle appear in two monophyletic clades distinct from yak, gaur and selembu. This study expresses the potential of the COI gene in portraying the phylogenetic relationships between several Bos species which is important for conservation efforts especially in decision making since cattle is highly bred and hybrid breeds are often formed. Genetic conservation for this high quality beef cattle breed is important by maintaining its genetic characters to prevent extinction or even decreased the genetic quality
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