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Fulltext An oil fraction neural sensor developed using electrical capacitance tomography sensor data

Zainal-Mokhtar K, Mohamad-Saleh J

Sensors (Basel), 2013;13(9):11385-406.
PMID: 24064598 DOI: 10.3390/s130911385

This paper presents novel research on the development of a generic intelligent oil fraction sensor based on Electrical Capacitance Tomography (ECT) data. An artificial Neural Network (ANN) has been employed as the intelligent system to sense and estimate oil fractions from the cross-sections of two-component flows comprising oil and gas in a pipeline. Previous works only focused on estimating the oil fraction in the pipeline based on fixed ECT sensor parameters. With fixed ECT design sensors, an oil fraction neural sensor can be trained to deal with ECT data based on the particular sensor parameters, hence the neural sensor is not generic. This work focuses on development of a generic neural oil fraction sensor based on training a Multi-Layer Perceptron (MLP) ANN with various ECT sensor parameters. On average, the proposed oil fraction neural sensor has shown to be able to give a mean absolute error of 3.05% for various ECT sensor sizes.
Investigating the Co-Movement and Asymmetric Relationships of Oil Prices on the Shipping Stock Returns: Evidence from Three Shipping-Flagged Companies from Germany, South Korea, and Taiwan

Saputra J, Mokhtar K, Abu Bakar A, Ruslan SMM

Big Data, 2024 Feb 13.
PMID: 38354271 DOI: 10.1089/big.2023.0026

In the last 2 years, there has been a significant upswing in oil prices, leading to a decline in economic activity and demand. This trend holds substantial implications for the global economy, particularly within the emerging business landscape. Among the influential risk factors impacting the returns of shipping stocks, none looms larger than the volatility in oil prices. Yet, only a limited number of studies have explored the complex relationship between oil price shocks and the dynamics of the liner shipping industry, with specific focus on uncertainty linkages and potential diversification strategies. This study aims to investigate the co-movements and asymmetric associations between oil prices (specifically, West Texas Intermediate and Brent) and the stock returns of three prominent shipping companies from Germany, South Korea, and Taiwan. The results unequivocally highlight the indispensable role of oil prices in shaping both short-term and long-term shipping stock returns. In addition, the research underscores the statistical significance of exchange rates and interest rates in influencing these returns, with their effects varying across different time horizons. Notably, shipping stock prices exhibit heightened sensitivity to positive movements in oil prices, while exchange rates and interest rates exert contrasting impacts, one being positive and the other negative. These findings collectively illuminate the profound influence of market sentiment regarding crucial economic indicators within the global shipping sector.
Synergistic effects of chitosan scaffold and TGFβ1 on the proliferation and osteogenic differentiation of dental pulp stem cells derived from human exfoliated deciduous teeth

Farea M, Husein A, Halim AS, Abdullah NA, Mokhtar KI, Lim CK, et al.

Arch Oral Biol, 2014 Dec;59(12):1400-11.
PMID: 25222336 DOI: 10.1016/j.archoralbio.2014.08.015

Multipotent stem cells derived from human exfoliated deciduous teeth (SHED) represent a promising cell source for tissue regeneration. In the present study we decided to test the inductive effect of chitosan and transforming growth factor-β1 (TGFβ1) as a scaffold/factor combination on SHED proliferation and osteogenic differentiation.
Cementoblastic lineage formation in the cross-talk between stem cells of human exfoliated deciduous teeth and epithelial rests of Malassez cells

Farea M, Husein A, Halim AS, Berahim Z, Nurul AA, Mokhtar KI, et al.

Clin Oral Investig, 2016 Jul;20(6):1181-91.
PMID: 26392396 DOI: 10.1007/s00784-015-1601-6

The purpose of this study was to evaluate the synergistic effect of epithelial rests of Malassez cells (ERM) and transforming growth factor-β1 (TGF-β1) on proliferation, cementogenic and osteogenic differentiation of stem cells derived from human exfoliated deciduous teeth (SHED).
Decarbonising ASEAN coastal shipping: Addressing climate change and coastal ecosystem issues through sustainable carbon neutrality strategies

Oloruntobi O, Chuah LF, Mokhtar K, Gohari A, Rady A, Abo-Eleneen RE, et al.

Environ Res, 2024 Jan 01;240(Pt 2):117353.
PMID: 37821061 DOI: 10.1016/j.envres.2023.117353

This study analyzes the impact of ASEAN's goal of achieving carbon neutrality by 2050 on climate change and coastal ecosystems by examining carbon emissions and energy usage from 2019 to 2050 using different scenarios to reduce emissions and meet global temperature goals. This research proposes strategies to reduce carbon emissions and mitigate climate change effects on coastal ecosystems, focusing on evaluating CO2 emissions from ASEAN's coastal shipping sector. Geospatial data was used to analyze ship activity and develop carbon neutrality strategies. Various sources are used to gather data, including the Maritime Portal, exact Earth AIS, FASA and GFW. This study finds that container ships emitted 13.7 × 106 t of CO2 in 2019, with the transportation sector contributing 3.8% of the total greenhouse gas in 2020. Without regulations, CO2 emissions could increase fourfold by 2050. The study recommends implementing policies such as adopting clean fuels, energy efficiency standards and fuel-related regulations to reduce CO2 emissions by 65-80% by 2050. It also emphasizes the importance of cleaner technologies, regulatory considerations and collaboration, which would have positive implications for coastal ecosystems. This study is beneficial to professionals in the maritime and shipping industries, policy makers, environmental consultants, sustainability specialists, and international organizations.
Fulltext Isolation and enhancement of a homogenous in vitro human Hertwig's epithelial root sheath cell population

Farea M, Halim AS, Abdullah NA, Lim CK, Mokhtar KI, Berahim Z, et al.

Int J Mol Sci, 2013;14(6):11157-70.
PMID: 23712356 DOI: 10.3390/ijms140611157

Hertwig's epithelial root sheath (HERS) cells play a pivotal role during root formation of the tooth and are able to form cementum-like tissue. The aim of the present study was to establish a HERS cell line for molecular and biochemical studies using a selective digestion method. Selective digestion was performed by the application of trypsin-EDTA for 2 min, which led to the detachment of fibroblast-like-cells, with the rounded cells attached to the culture plate. The HERS cells displayed a typical cuboidal/squamous-shaped appearance. Characterization of the HERS cells using immunofluorescence staining and flow cytometry analysis showed that these cells expressed pan-cytokeratin, E-cadherin, and p63 as epithelial markers. Moreover, RT-PCR confirmed that these cells expressed epithelial-related genes, such as cytokeratin 14, E-cadherin, and ΔNp63. Additionally, HERS cells showed low expression of CD44 and CD105 with absence of CD34 and amelogenin expressions. In conclusion, HERS cells have been successfully isolated using a selective digestion method, thus enabling future studies on the roles of these cells in the formation of cementum-like tissue in vitro.
Implementation of the energy efficiency existing ship index and carbon intensity indicator on domestic ship for marine environmental protection

Chuah LF, Mokhtar K, Mhd Ruslan SM, Bakar AA, Abdullah MA, Osman NH, et al.

Environ Res, 2023 Apr 01;222:115348.
PMID: 36731596 DOI: 10.1016/j.envres.2023.115348

The International Maritime Organization has set a goal to achieve a 50% reduction of total annual greenhouse gas emission related to the international shipping by 2050 compared to the 2008 baseline emissions. Malaysia government has taken an initiative to investigate the assessment (cost-effectiveness) of this International Maritime Organization's short-term measure on Malaysian-registered domestic ships although this measure is only for international merchant ship. To achieve this, this paper collected the ship's data from the shipowners from 25 sample ships. Engine power limitation is the most cost-effective option, but low power limits can lead to substantially increased sailing times. Based on cost-efficiency analysis, it creates for the purpose of compliance with the operational carbon intensity indicator. It found that even if it is possible to bring an asset back into service, it may not be possible to do so in a manner that generates a profit or complies with applicable regulations. In these situations, it may be more prudent to scrap the asset rather than run the risk of having it become a stranded asset. This is especially true for older tankers. Alternatives with lengthy payback periods are not desirable for the domestic tanker fleet that is already in operation.
Fulltext Nanometal Dust Explosion in Confined Vessel: Combustion and Kinetic Analysis

Mohd Mokhtar K, Kasmani RM, Che Hassan CR, Hamid MD, Mohamad Nor MI, Mohd Junaidi MU, et al.

ACS Omega, 2021 Jul 20;6(28):17831-17838.
PMID: 34308018 DOI: 10.1021/acsomega.1c00967

Extensive application of metal powder, particularly in nanosize could potentially lead to catastrophic dust explosion, due to their pyrophoric behavior, ignition sensitivity, and explosivity. To assess the appropriate measures preventing accidental metal dust explosions, it is vital to understand the physicochemical properties of the metal dust and their kinetic mechanism. In this work, explosion severity of aluminum and silver powder, which can be encountered in a passivated emitter and rear contact (PERC) solar cell, was explored in a 0.0012 m3 cylindrical vessel, by varying the particle size and powder concentration. The P max and dP/dt max values of metal powder were demonstrated to increase with decreasing particle size. Additionally, it was found that the explosion severity of silver powder was lower than that of aluminum powder due to the more apparent agglomeration effect of silver particles. The reduction on the specific surface area attributed to the particles' agglomeration affects the oxidation reaction of the metal powder, as illustrated in the thermogravimetric (TG) curves. A sluggish oxidation reaction was demonstrated in the TG curve of silver powder, which is contradicted with aluminum powder. From the X-ray photoelectron spectroscopy (XPS) analysis, it is inferred that silver powder exhibited two reactions in which the dominant reaction produced Ag and the other reaction formed Ag2O. Meanwhile, for aluminum powder, explosion products only comprise Al2O3.
Assessing coastal bathymetry and climate change impacts on coastal ecosystems using Landsat 8 and Sentinel-2 satellite imagery

Mokhtar K, Chuah LF, Abdullah MA, Oloruntobi O, Ruslan SMM, Albasher G, et al.

Environ Res, 2023 Dec 15;239(Pt 2):117314.
PMID: 37805186 DOI: 10.1016/j.envres.2023.117314

Coastal ecosystems are facing heightened risks due to human-induced climate change, including rising water levels and intensified storm events. Accurate bathymetry data is crucial for assessing the impacts of these threats. Traditional data collection methods can be cost-prohibitive. This study investigates the feasibility of using freely accessible Landsat and Sentinel satellite imagery to estimate bathymetry and its correlation with hydrographic chart soundings in Port Klang, Malaysia. Through analysis of the blue and green spectral bands from the Landsat 8 and Sentinel 2 datasets, a bathymetry map of Port Klang's seabed is generated. The precision of this derived bathymetry is evaluated using statistical metrics like Root Mean Square Error (RMSE) and the coefficient of determination. The results reveal a strong statistical connection (R2 = 0.9411) and correlation (R2 = 0.7958) between bathymetry data derived from hydrographic chart soundings and satellite imagery. This research not only advances our understanding of employing Landsat imagery for bathymetry assessment but also underscores the significance of such assessments in the context of climate change's impact on coastal ecosystems. The primary goal of this research is to contribute to the comprehension of Landsat imagery's utility in bathymetry evaluation, with the potential to enhance safety protocols in seaport terminals and provide valuable insights for decision-making concerning the management of coastal ecosystems amidst climate-related challenges. The findings of this research have practical implications for a wide range of stakeholders involved in coastal management, environmental protection, climate adaptation and disaster preparedness.
Enhancing coastal ecosystem resilience: Investigating the interplay between safety criteria and ferry employee's perceptions to address climate change impacts

Azmi MA, Mokhtar K, Osnin NA, Razali Chan S, Albasher G, Ali A, et al.

Environ Res, 2023 Dec 01;238(Pt 1):117074.
PMID: 37678506 DOI: 10.1016/j.envres.2023.117074

Coastal ecosystems play an important part in mitigating the effects of climate change. Coastal ecosystems are becoming more susceptible to climate change impacts due to human activities and maritime accidents. The global shipping industry, especially in Southeast Asia, has witnessed numerous accidents, particularly involving passenger ferries, resulting in injuries and fatalities in recent years. In order to mitigate the impact of climate change on coastal ecosystems, this study aimed to evaluate the relationship between employees' perceptions of safety criteria and their own safety behaviour on Langkawi Island, Malaysia. A straightforward random sampling technique was employed to collect data from 112 ferry employees aboard Malaysian-registered passenger boats by administering questionnaires. The findings shed light on the strong connection between providing safety instructions for passengers and safety behaviour among ferry workers. Safety instructions should contain climate-related information to successfully address the effects of climate change. The instructions might include guidance on responding to extreme weather events and understanding the potential consequences of sea-level rise on coastal communities. The ferry company staff should also expand their safe behaviour concept to include training and preparation for climate-related incidents. The need to recognise the interconnectedness between climate change, ferry safety and the protection of coastal ecosystems is emphasised in this study. The findings can be utilised by policymakers, regulatory agencies and ferry operators to design holistic policies that improve safety behaviour, minimise maritime mishaps and preserve the long-term sustainability of coastal ecosystems in the face of difficulties posed by climate change.
Fulltext Preliminary Comparative Study of Oral7® Versus Salt-Soda Mouthwash on Oral Health Related Problems and Quality of Life among Head and Neck Cancer Patients Undergoing Radiotherapy

Bachok N, Biswal BM, Razak NHA, Zainoon WMNW, Mokhtar K, Rahman RA, et al.

Malays J Med Sci, 2018 Sep;25(5):79-87.
PMID: 30914865 MyJurnal DOI: 10.21315/mjms2018.25.5.8

Background: This quasi-clinical trial compared the effects of Oral7® and salt-soda mouthwash on the development of dental caries, salivary gland function, radiation mucositis, xerostomia and EORTC QLQ H&N C35 scores in head and neck cancer patients who underwent radiotherapy.
Methods: We included patients with histopathologically diagnosed head and neck cancers who had received radiation, with an Eastern Cooperative Oncology Group (ECOG) performance status 0-1 and age range of 15-60 years. Patients with prior radiotherapy and chemotherapy, edentulous status, total parotidectomy, sicca syndrome or on xerosis-induced medications were excluded. We assigned 15 patients each to the Oral7® and salt-soda groups.
Results: There was no significant difference in the mean Decayed, Missing and Filling Teeth (DMFT) score between groups. Head and neck cancer patients who were on Oral7® had a significantly better quality of life than those on salt-soda in relation to the swallowing problems, social eating, mouth opening, xerostomia and illness scales. Patients who were on Oral7® had a significantly lower xerostomia score than patients on salt-soda mouthwash. Patients on Oral7® had a significantly lower mucositis score in week 5-7 compared to patients in the salt-soda group.
Conclusion: Oral7® showed advantages over salt-soda solution in relation to reducing xerostomia, easing radiation-induced mucositis, and improving quality of life, despite the non-significant difference in the dental caries assessment.

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