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  1. Fulltext Performance analysis of the Microsoft Kinect sensor for 2D Simultaneous Localization and Mapping (SLAM) techniques
    Kamarudin K, Mamduh SM, Shakaff AY, Zakaria A
    Sensors (Basel), 2014;14(12):23365-87.
    PMID: 25490595 DOI: 10.3390/s141223365
    This paper presents a performance analysis of two open-source, laser scanner-based Simultaneous Localization and Mapping (SLAM) techniques (i.e., Gmapping and Hector SLAM) using a Microsoft Kinect to replace the laser sensor. Furthermore, the paper proposes a new system integration approach whereby a Linux virtual machine is used to run the open source SLAM algorithms. The experiments were conducted in two different environments; a small room with no features and a typical office corridor with desks and chairs. Using the data logged from real-time experiments, each SLAM technique was simulated and tested with different parameter settings. The results show that the system is able to achieve real time SLAM operation. The system implementation offers a simple and reliable way to compare the performance of Windows-based SLAM algorithm with the algorithms typically implemented in a Robot Operating System (ROS). The results also indicate that certain modifications to the default laser scanner-based parameters are able to improve the map accuracy. However, the limited field of view and range of Kinect's depth sensor often causes the map to be inaccurate, especially in featureless areas, therefore the Kinect sensor is not a direct replacement for a laser scanner, but rather offers a feasible alternative for 2D SLAM tasks.
  2. Antioxidant activities and tyrosinase inhibition effects of Phaleria macrocarpa extracts
    Nadri MH, Salim Y, Basar N, Yahya A, Zulkifli RM
    Afr J Tradit Complement Altern Med, 2014;11(3):107-11.
    PMID: 25371571
    BACKGROUND: The ethyl acetate and chloroform extracts of stems, leaves and fruits of Phaleria macrocarpa were screened for their antioxidant capacity and tyrosinase inhibition properties.

    MATERIAL AND METHOD: The total phenolic content (TPC), 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and ferric-ion reducing power (FRAP) were used to evaluate their antioxidant capacity. Tyrosinase inhibition effect was measured using mushroom tyrosinase inhibition assay.

    RESULT: Ethyl acetate extract of P. macrocarpa's stem exhibited highest total phenolic content, DPPH free radical scavenging and ferric reducing power. Meanwhile, chloroform extracts of leaves and fruits demonstrated potent anti-tyrosinase activities as compared to a well-known tyrosinase inhibitor, kojic acid.

    CONCLUSION: Since chloroform extracts of leaves and fruits have low antioxidant capacities, the tyrosinase inhibition effect observed are antioxidant independent. This study suggests direct tyrosinase inhibition by chloroform extracts of Phaleria macrocarpa.

  3. Fulltext Can Pharmacy Doctors act as valuable assets in rural areas with a physician shortage?
    Ahmad A, Patel I, Khan MU, Chang J
    J Res Pharm Pract, 2014 Oct;3(4):109-11.
    PMID: 25535617 DOI: 10.4103/2279-042X.145345
  4. First record of genus Puliciphora Dahl (Diptera: Phoridae) associated with rabbit carcasses placed in concealed environments in Malaysia
    Zuha RM, See HW, Disney RH, Omar B
    Forensic Sci Int, 2014 Dec;245:e36-7.
    PMID: 25466156 DOI: 10.1016/j.forsciint.2014.10.034
    Scuttle flies of genus Puliciphora Dahl (Diptera: Phoridae) are recorded for the first time in Malaysia from rabbit carcasses placed in concealed environments. They consist of Puliciphora borinquenensis Wheeler ♂♀, Puliciphora obtecta Meijere ♀ and Puliciphora beckeri Meijere ♀. All species were obtained from rabbit carcasses in used luggage and garbage bin placed at Forensic Science Simulation Site, Universiti Kebangsaan Malaysia, Bangi, Selangor. The specimens were collected from the carcasses using a modified Malaise trap, an entomological aspirator and preserved in 70% ethanol. This report expands the geographical distributions of these species and their microhabitat, suggests its possible important role in forensic entomology.
  5. Antioxidative and chemopreventive effects of Nephrolepis biserrata against carbon tetrachloride (CCl4)-induced oxidative stress and hepatic dysfunction in rats
    Shah MD, Gnanaraj C, Haque AT, Iqbal M
    Pharm Biol, 2015 Jan;53(1):31-9.
    PMID: 25243876 DOI: 10.3109/13880209.2014.909502
    Nephrolepis biserrata L. (Nephrolepidaceae) has been used in folk medicine for protection against different diseases.
  6. Fulltext Efficient feature selection and classification of protein sequence data in bioinformatics
    Iqbal MJ, Faye I, Samir BB, Said AM
    ScientificWorldJournal, 2014;2014:173869.
    PMID: 25045727 DOI: 10.1155/2014/173869
    Bioinformatics has been an emerging area of research for the last three decades. The ultimate aims of bioinformatics were to store and manage the biological data, and develop and analyze computational tools to enhance their understanding. The size of data accumulated under various sequencing projects is increasing exponentially, which presents difficulties for the experimental methods. To reduce the gap between newly sequenced protein and proteins with known functions, many computational techniques involving classification and clustering algorithms were proposed in the past. The classification of protein sequences into existing superfamilies is helpful in predicting the structure and function of large amount of newly discovered proteins. The existing classification results are unsatisfactory due to a huge size of features obtained through various feature encoding methods. In this work, a statistical metric-based feature selection technique has been proposed in order to reduce the size of the extracted feature vector. The proposed method of protein classification shows significant improvement in terms of performance measure metrics: accuracy, sensitivity, specificity, recall, F-measure, and so forth.
  7. Fulltext An adaptive learning rate for RBFNN using time-domain feedback analysis
    Ali SS, Moinuddin M, Raza K, Adil SH
    ScientificWorldJournal, 2014;2014:850189.
    PMID: 24987745 DOI: 10.1155/2014/850189
    Radial basis function neural networks are used in a variety of applications such as pattern recognition, nonlinear identification, control and time series prediction. In this paper, the learning algorithm of radial basis function neural networks is analyzed in a feedback structure. The robustness of the learning algorithm is discussed in the presence of uncertainties that might be due to noisy perturbations at the input or to modeling mismatch. An intelligent adaptation rule is developed for the learning rate of RBFNN which gives faster convergence via an estimate of error energy while giving guarantee to the l 2 stability governed by the upper bounding via small gain theorem. Simulation results are presented to support our theoretical development.
  8. Fulltext Minimizing thermal stress for data center servers through thermal-aware relocation
    Chaudhry MT, Ling TC, Hussain SA, Manzoor A
    ScientificWorldJournal, 2014;2014:684501.
    PMID: 24987743 DOI: 10.1155/2014/684501
    A rise in inlet air temperature may lower the rate of heat dissipation from air cooled computing servers. This introduces a thermal stress to these servers. As a result, the poorly cooled active servers will start conducting heat to the neighboring servers and giving rise to hotspot regions of thermal stress, inside the data center. As a result, the physical hardware of these servers may fail, thus causing performance loss, monetary loss, and higher energy consumption for cooling mechanism. In order to minimize these situations, this paper performs the profiling of inlet temperature sensitivity (ITS) and defines the optimum location for each server to minimize the chances of creating a thermal hotspot and thermal stress. Based upon novel ITS analysis, a thermal state monitoring and server relocation algorithm for data centers is being proposed. The contribution of this paper is bringing the peak outlet temperatures of the relocated servers closer to average outlet temperature by over 5 times, lowering the average peak outlet temperature by 3.5% and minimizing the thermal stress.
  9. Pharmacological evaluation and docking studies of α,β-unsaturated carbonyl based synthetic compounds as inhibitors of secretory phospholipase A₂, cyclooxygenases, lipoxygenase and proinflammatory cytokines
    Bukhari SN, Lauro G, Jantan I, Bifulco G, Amjad MW
    Bioorg Med Chem, 2014 Aug 1;22(15):4151-61.
    PMID: 24938495 DOI: 10.1016/j.bmc.2014.05.052
    Arachidonic acid and its metabolites have generated high level of interest among researchers due to their vital role in inflammation. The inhibition of enzymes involved in arachidonic acid metabolism has been considered as synergistic anti-inflammatory effect. A series of novel α,β-unsaturated carbonyl based compounds were synthesized and evaluated for their inhibitory activity on secretory phospholipase A₂ (sPLA₂), cyclooxygenases (COX), soybean lipoxygenase (LOX) in addition to proinflammatory cytokines comprising IL-6 and TNF-α. Six α,β-unsaturated carbonyl based compounds (2, 3, 4, 12, 13 and 14) exhibited strong inhibition of sPLA₂ activity, with IC₅₀ values in the range of 2.19-8.76 μM. Nine compounds 1-4 and 10-14 displayed inhibition of COX-1 with IC₅₀ values ranging from 0.37 to 1.77 μM (lower than that of reference compound), whereas compounds 2, 10, 13 and 14 strongly inhibited the COX-2. The compounds 10-14 exhibited strong inhibitory activity against LOX enzyme. All compounds were evaluated for the inhibitory activities against LPS-induced TNF-α and IL-6 release in the macrophages. On the basis of screening results, five active compounds 3, 4, 12, 13 and 14 were found strong inhibitors of TNF-α and IL-6 release in a dose-dependent manner. Molecular docking experiments were performed to clarify the molecular aspects of the observed COX and LOX inhibitory activities of the investigated compounds. Present findings increases the possibility that these α,β-unsaturated carbonyl based compounds might serve as beneficial starting point for the design and development of improved anti-inflammatory agents.
  10. Limited diagnostic value of two commercial rapid tests for acute leptospirosis detection in Malaysia
    Chang CH, Riazi M, Yunus MH, Osman S, Noordin R
    Diagn Microbiol Infect Dis, 2014 Dec;80(4):278-81.
    PMID: 25241641 DOI: 10.1016/j.diagmicrobio.2014.08.012
    This study evaluated 2 rapid leptospirosis serological tests, Leptorapide® (Linnodee, Northern Ireland) and VISITECT®-LEPTO (Omega Diagnostics, Scotland, UK), which are commonly used in Malaysia. A total of 183 samples comprised 113 sera from leptospirosis patients, and 70 sera from other infections and healthy controls were used. The leptospirosis sera were grouped into 2 serum panels, i.e., Group I (MAT+, PCR+) and Group II (MAT+). When inconclusive results were interpreted as positives, both tests showed lower diagnostic sensitivities (≤ 34%) with Group I sera, as compared to Group II sera (Leptorapide®, 93%; VISITECT®-LEPTO, 40%). When inconclusive results were interpreted as negatives, the 2 tests showed ~20% sensitivity with both serum panels. The diagnostic specificity of VISITECT®-LEPTO (94%) was superior to Leptorapide® (69%). Since both tests had misdiagnosed a large proportion of Group I patients and showed many inconclusive results among Group II patients, they have limited diagnostic value in detecting acute leptospirosis.
  11. Correlation of tumour response with starting tumour size and dose of tamoxifen in an N-methyl-N-nitrosourea (NMU)-induced rat mammary cancer model
    Yankuzo HM, Emilia ST, Shaari R, Yaacob NS
    Asian Pac J Cancer Prev, 2014;15(16):6721-6.
    PMID: 25169515
    BACKGROUND: The aim of this preliminary study was to address variations of responses observed with different starting tumor sizes of 10 and 15 mm, and the effects of different doses of tamoxifen (TAM) on experimental rat mammary tumors.

    MATERIALS AND METHODS: Thirty-five inbred female Sprague Dawley rats aged 43 days were administered with three weekly doses of N-methyl-N-nitrosourea (NMU) intraperitoneally (ip) at 50 mg/kg body weight. Animals were randomized (beginning from 10 mm tumor size) into four TAM-treated (50, 100, 200 and 500 μg/day) groups of six animals each, and another group (n=6) treated with TAM 100 μg/day at starting tumour size of 15 mm. The animals were treated by oral gavage daily for 8 weeks before sacrifice.

    RESULTS: Serum urea and creatinine, and overall physical tumor burden were significantly modulated in animals treated with variable doses of TAM compared to the untreated controls (n=5). Final body weight and tumor number were significantly different in the 10 mm-treated animals compared to those treated at 15 mm. There were no significant differences in histopathological features among all the groups.

    CONCLUSIONS: Our findings suggest the importance of standardizing tumour size and drug doses before initiation of treatment, particularly in the direct comparison of basic end-tumour physical parameters.

  12. Fulltext RSM based optimization of chemical and enzymatic transesterification of palm oil: biodiesel production and assessment of exhaust emission levels
    Mumtaz MW, Mukhtar H, Anwar F, Saari N
    ScientificWorldJournal, 2014;2014:526105.
    PMID: 25162053 DOI: 10.1155/2014/526105
    Current study presents RSM based optimized production of biodiesel from palm oil using chemical and enzymatic transesterification. The emission behavior of biodiesel and its blends, namely, POB-5, POB-20, POB-40, POB-50, POB-80, and POB-100 was examined using diesel engine (equipped with tube well). Optimized palm oil fatty acid methyl esters (POFAMEs) yields were depicted to be 47.6 ± 1.5, 92.7 ± 2.5, and 95.4 ± 2.0% for chemical transesterification catalyzed by NaOH, KOH, and NaOCH3, respectively, whereas for enzymatic transesterification reactions catalyzed by NOVOZYME-435 and A. n. lipase optimized biodiesel yields were 94.2 ± 3.1 and 62.8 ± 2.4%, respectively. Distinct decrease in particulate matter (PM) and carbon monoxide (CO) levels was experienced in exhaust emissions from engine operating on biodiesel blends POB-5, POB-20, POB-40, POB-50, POB-80, and POB-100 comparative to conventional petroleum diesel. Percentage change in CO and PM emissions for different biodiesel blends ranged from -2.1 to -68.7% and -6.2 to -58.4%, respectively, relative to conventional diesel, whereas an irregular trend was observed for NOx emissions. Only POB-5 and POB-20 showed notable reductions, whereas all other blends (POB-40 to POB-100) showed slight increase in NOx emission levels from 2.6 to 5.5% comparative to petroleum diesel.
  13. Fulltext Towards dynamic remote data auditing in computational clouds
    Sookhak M, Akhunzada A, Gani A, Khurram Khan M, Anuar NB
    ScientificWorldJournal, 2014;2014:269357.
    PMID: 25121114 DOI: 10.1155/2014/269357
    Cloud computing is a significant shift of computational paradigm where computing as a utility and storing data remotely have a great potential. Enterprise and businesses are now more interested in outsourcing their data to the cloud to lessen the burden of local data storage and maintenance. However, the outsourced data and the computation outcomes are not continuously trustworthy due to the lack of control and physical possession of the data owners. To better streamline this issue, researchers have now focused on designing remote data auditing (RDA) techniques. The majority of these techniques, however, are only applicable for static archive data and are not subject to audit the dynamically updated outsourced data. We propose an effectual RDA technique based on algebraic signature properties for cloud storage system and also present a new data structure capable of efficiently supporting dynamic data operations like append, insert, modify, and delete. Moreover, this data structure empowers our method to be applicable for large-scale data with minimum computation cost. The comparative analysis with the state-of-the-art RDA schemes shows that the proposed scheme is secure and highly efficient in terms of the computation and communication overhead on the auditor and server.
  14. Fulltext Stochastic optimized relevance feedback particle swarm optimization for content based image retrieval
    Imran M, Hashim R, Noor Elaiza AK, Irtaza A
    ScientificWorldJournal, 2014;2014:752090.
    PMID: 25121136 DOI: 10.1155/2014/752090
    One of the major challenges for the CBIR is to bridge the gap between low level features and high level semantics according to the need of the user. To overcome this gap, relevance feedback (RF) coupled with support vector machine (SVM) has been applied successfully. However, when the feedback sample is small, the performance of the SVM based RF is often poor. To improve the performance of RF, this paper has proposed a new technique, namely, PSO-SVM-RF, which combines SVM based RF with particle swarm optimization (PSO). The aims of this proposed technique are to enhance the performance of SVM based RF and also to minimize the user interaction with the system by minimizing the RF number. The PSO-SVM-RF was tested on the coral photo gallery containing 10908 images. The results obtained from the experiments showed that the proposed PSO-SVM-RF achieved 100% accuracy in 8 feedback iterations for top 10 retrievals and 80% accuracy in 6 iterations for 100 top retrievals. This implies that with PSO-SVM-RF technique high accuracy rate is achieved at a small number of iterations.
  15. Description of raabeia, synactinomyxon and neoactinomyxum developing stages of myxosporeans (Myxozoa) infecting Isochaetides michaelseni Lastočkin (Tubificidae) in Lake Balaton and Kis-Balaton Water Reservoir, Hungary
    Borkhanuddin MH, Cech G, Molnár K, Németh S, Székely C
    Syst Parasitol, 2014 Jul;88(3):245-59.
    PMID: 24935127 DOI: 10.1007/s11230-014-9496-1
    Molecular and morphometric investigations were conducted on the actinosporean morphotypes of myxosporeans surveyed in oligochaetes of Lake Balaton and Kis-Balaton Water reservoir. Oligochaetes belonging to the species Isochaetides michaelseni Lastočkin and Branchiura sowerbyi Beddard as well as to the genera Nais Dujardin, Dero Müller and Aeolosoma Ehrenberg were studied during an 18-month period. Actinosporeans were obtained exclusively from I. michaelseni (7,818 specimens) with very low prevalence (0.01-0.06%). Four new actinosporean morphotypes of the collective groups raabeia (2 types), synactinomyxon (1 type) and neoactinomyxum (1 type) were found and described, including the first synactinomyxon collective group from Hungarian biotopes and a new raabeia morphotype. Except for Synactinomyxon type 1, the 18S rDNA analysis revealed that the spores did not match any myxospore entity found in the GenBank.
  16. Fulltext Severe Plasmodium falciparum infection mimicking acute myocardial infarction
    Sulaiman H, Ismail MD, Jalalonmuhali M, Atiya N, Ponnampalavanar S
    Malar J, 2014;13:341.
    PMID: 25176417 DOI: 10.1186/1475-2875-13-341
    This case report describes a case of presumed acute myocardial infarction in a returned traveler who was later diagnosed to have severe malaria. Emergency coronary angiography was normal and subsequent peripheral blood film was positive for Plasmodium falciparum.
  17. Fulltext An energy efficient simultaneous-node repositioning algorithm for mobile sensor networks
    Khan MA, Hasbullah H, Nazir B, Khan IA
    ScientificWorldJournal, 2014;2014:785305.
    PMID: 25152924 DOI: 10.1155/2014/785305
    Recently, wireless sensor network (WSN) applications have seen an increase in interest. In search and rescue, battlefield reconnaissance, and some other such applications, so that a survey of the area of interest can be made collectively, a set of mobile nodes is deployed. Keeping the network nodes connected is vital for WSNs to be effective. The provision of connectivity can be made at the time of startup and can be maintained by carefully coordinating the nodes when they move. However, if a node suddenly fails, the network could be partitioned to cause communication problems. Recently, several methods that use the relocation of nodes for connectivity restoration have been proposed. However, these methods have the tendency to not consider the potential coverage loss in some locations. This paper addresses the concerns of both connectivity and coverage in an integrated way so that this gap can be filled. A novel algorithm for simultaneous-node repositioning is introduced. In this approach, each neighbour of the failed node, one by one, moves in for a certain amount of time to take the place of the failed node, after which it returns to its original location in the network. The effectiveness of this algorithm has been verified by the simulation results.
  18. Fulltext Development of phase detection schemes based on surface plasmon resonance using interferometry
    Kashif M, Bakar AA, Arsad N, Shaari S
    Sensors (Basel), 2014 Aug 28;14(9):15914-38.
    PMID: 25171117 DOI: 10.3390/s140915914
    Surface plasmon resonance (SPR) is a novel optical sensing technique with a unique ability to monitor molecular binding in real-time for biological and chemical sensor applications. Interferometry is an excellent tool for accurate measurement of SPR changes, the measurement and comparison is made for the sensitivity, dynamic range and resolution of the different analytes using interferometry techniques. SPR interferometry can also employ phase detection in addition to the amplitude of the reflected light wave, and the phase changes more rapidly compared with other approaches, i.e., intensity, angle and wavelength. Therefore, the SPR phase interferometer offers the advantages of spatial phase resolution and high sensitivity. This work discusses the advancements in interferometric SPR methods to measure the phase shifts due to refractive index changes. The main application areas of SPR sensors are demonstrated, i.e., the Fabry-Perot interferometer, Michelson interferometer and Mach-Zehnder interferometer, with different configurations. The three interferometers are discussed in detail, and solutions are suggested to enhance the performance parameters that will aid in future biological and chemical sensors.
  19. Fulltext Climate change: a review of its health impact and perceived awareness by the young citizens
    Rahman MS, Mohamad OB, Zarim Zb
    Glob J Health Sci, 2014 Jul;6(4):196-204.
    PMID: 24999143 DOI: 10.5539/gjhs.v6n4p196
    In recent time climate change and its impact on human health and awareness constitute a set of complex and serious consequences to be tackled by an individual country. Climate change is not merely an environmental issue, but also it is a threat that goes beyond national borders. The purpose of this study is to identify the awareness and the impact of climate change, perceived by the young citizens in Malaysia by focusing on gender differences. Based on a survey of 200 respondents from different public and private University's students in Malaysia, this research used descriptive statistics and T-test to look into the research objective. The results revealed media can play an important role in the awareness of climate change. Meanwhile the male respondents have shown considerable attention on the physical impact of climate change like heat related stress. On the other hand female respondents have shown considerable attention to the psychological impact by the climate change. From a pragmatic perspective, the findings from this research will assists the policy makers to understand more about the perceived awareness on the climate change issues of the young citizens which ultimately assist them to inaugurate new initiatives to confront the challenges of climate changes. This research is among the pioneer study on the issue of the perceived awareness in regards to climate change in Malaysia by focusing on gender differences.
  20. Fulltext Strength development of high-strength ductile concrete incorporating Metakaolin and PVA fibers
    Nuruddin MF, Khan SU, Shafiq N, Ayub T
    ScientificWorldJournal, 2014;2014:387259.
    PMID: 24707202 DOI: 10.1155/2014/387259
    The mechanical properties of high-strength ductile concrete (HSDC) have been investigated using Metakaolin (MK) as the cement replacing material and PVA fibers. Total twenty-seven (27) mixes of concrete have been examined with varying content of MK and PVA fibers. It has been found that the coarser type PVA fibers provide strengths competitive to control or higher than control. Concrete with coarser type PVA fibers has also refined microstructure, but the microstructure has been undergone with the increase in aspect ratio of fibers. The microstructure of concrete with MK has also more refined and packing of material is much better with MK. PVA fibers not only give higher stiffness but also showed the deflection hardening response. Toughness Index of HSDC reflects the improvement in flexural toughness over the plain concrete and the maximum toughness indices have been observed with 10% MK and 2% volume fraction of PVA fibers.
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