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Simulated seasonal oceanographic changes and their implication for the small pelagic fisheries in the Java Sea, Indonesia

Apriansyah, Atmadipoera AS, Nugroho D, Jaya I, Akhir MF

Mar Environ Res, 2023 Jun;188:106012.
PMID: 37159981 DOI: 10.1016/j.marenvres.2023.106012

Small pelagic fisheries in the Java Sea (JS) contributes to about 26.6% of the total marine fisheries resources, where their spatial-temporal variation is controlled by seasonal oceanographic changes. This study aims to investigate a relationship between seasonal reversal circulation and number of light-fishing vessels (VBD) dispersion that capture small pelagic fishes, using multi-datasets from a regional ocean circulation model, satellite-derived datasets, and pelagic fish landing datasets between 2010 and 2020. The model demonstrates that main axis of eastward (westward) monsoon current that brings warmer and fresher (cooler and saltier) water, confines much closer along the northern Java (southern Kalimantan) during the northwest (southeast) monsoon period. These changes are followed unprecedentedly by southward (northward) shift of VBD and high abundance of euryhaline (stenohaline) fish species. This new evidence implies that reversal monsoon current and surface component of Makassar Throughflow play a significant role on delineating potential small pelagic fishing ground and fish productions.
Fulltext Phylogenetic analysis of simian Plasmodium spp. infecting Anopheles balabacensis Baisas in Sabah, Malaysia

Chua TH, Manin BO, Daim S, Vythilingam I, Drakeley C

PLoS Negl Trop Dis, 2017 Oct;11(10):e0005991.
PMID: 28968395 DOI: 10.1371/journal.pntd.0005991

BACKGROUND: Anopheles balabacensis of the Leucospyrus group has been confirmed as the primary knowlesi malaria vector in Sabah, Malaysian Borneo for some time now. Presently, knowlesi malaria is the only zoonotic simian malaria in Malaysia with a high prevalence recorded in the states of Sabah and Sarawak.
METHODOLOGY/PRINCIPAL FINDINGS: Anopheles spp. were sampled using human landing catch (HLC) method at Paradason village in Kudat district of Sabah. The collected Anopheles were identified morphologically and then subjected to total DNA extraction and polymerase chain reaction (PCR) to detect Plasmodium parasites in the mosquitoes. Identification of Plasmodium spp. was confirmed by sequencing the SSU rRNA gene with species specific primers. MEGA4 software was then used to analyse the SSU rRNA sequences and bulid the phylogenetic tree for inferring the relationship between simian malaria parasites in Sabah. PCR results showed that only 1.61% (23/1,425) of the screened An. balabacensis were infected with one or two of the five simian Plasmodium spp. found in Sabah, viz. Plasmodium coatneyi, P. inui, P. fieldi, P. cynomolgi and P. knowlesi. Sequence analysis of SSU rRNA of Plasmodium isolates showed high percentage of identity within the same Plasmodium sp. group. The phylogenetic tree based on the consensus sequences of P. knowlesi showed 99.7%-100.0% nucleotide identity among the isolates from An. balabacensis, human patients and a long-tailed macaque from the same locality.
CONCLUSIONS/SIGNIFICANCE: This is the first study showing high molecular identity between the P. knowlesi isolates from An. balabacensis, human patients and a long-tailed macaque in Sabah. The other common simian Plasmodium spp. found in long-tailed macaques and also detected in An. balabacensis were P. coatneyi, P. inui, P. fieldi and P. cynomolgi. The high percentage identity of nucleotide sequences between the P. knowlesi isolates from the long-tailed macaque, An. balabacensis and human patients suggests a close genetic relationship between the parasites from these hosts.
Fulltext Agricultural land resource allocation to develop food crop commodities: lesson from Indonesia

Nasikh, Kamaludin M, Narmaditya BS, Wibowo A, Febrianto I

Heliyon, 2021 Jul;7(7):e07520.
PMID: 34307945 DOI: 10.1016/j.heliyon.2021.e07520

This study estimates agricultural land resource allocation to develop food-crop commodities in order to safeguard food security in Indonesia in the middle of the coronavirus pandemic. The recommended commodities to be developed in Indonesia are corn, soybean, mungbean, peanut, and rice that are produced with advanced technology and input-output coefficient. There are five introduced scenarios namely, basic scenario, I, II, III, and IV. There are problems related to resource allocation such as limited resources, the ways of using it, and time constraints. In order to maintain and improve the comparative advantage of agricultural production as well as to broaden the agricultural activities, agricultural development is directed to increase business efficiency, improvements in agricultural science, technology, and human resource quality. The utilization of agricultural land resources should be well-planned for better development.
Fulltext The Yield Prediction of Synthetic Fuel Production from Pyrolysis of Plastic Waste by Levenberg-Marquardt Approach in Feedforward Neural Networks Model

Abnisa F, Anuar Sharuddin SD, Bin Zanil MF, Wan Daud WMA, Indra Mahlia TM

Polymers (Basel), 2019 Nov 10;11(11).
PMID: 31717695 DOI: 10.3390/polym11111853

The conversion of plastic waste into fuel by pyrolysis has been recognized as a potential strategy for commercialization. The amount of plastic waste is basically different for each country which normally refers to non-recycled plastics data; consequently, the production target will also be different. This study attempted to build a model to predict fuel production from different non-recycled plastics data. The predictive model was developed via Levenberg-Marquardt approach in feed-forward neural networks model. The optimal number of hidden neurons was selected based on the lowest total of the mean square error. The proposed model was evaluated using the statistical analysis and graphical presentation for its accuracy and reliability. The results showed that the model was capable to predict product yields from pyrolysis of non-recycled plastics with high accuracy and the output values were strongly correlated with the values in literature.
Fulltext Open surgical exposure of two horizontally impacted maxillary incisors combined with orthodontic treatment: A case report

Alhasyimi AA, Indra P, Setijanto RD, Tajudin AM, Noviasari P, Rosanto YB

Int J Surg Case Rep, 2024 May;118:109620.
PMID: 38615467 DOI: 10.1016/j.ijscr.2024.109620

INTRODUCTION: Maxillary anterior teeth that have not erupted may substantially alter the appearance of the teeth and face. Orthodontists often encounter a clinical challenge while dealing with an impacted maxillary incisor, which creates space problems in the anterior region. The purpose of this paper is to describe the well-synchronized orthodontic and surgical treatment of a horizontally impacted maxillary central incisors.
CASE PRESENTATION: A male patient, aged 27, presented with a complaint of unerupted two maxillary front teeth. This resulted in the displacement of adjacent teeth into the vacant region. An intraoral examination revealed a Class II molars on both sides, a deep curve of the space with a 2.3 mm overjet, and an edge-to-edge bite of 0.1 mm. The 3D cone beam computed tomography (CBCT) imaging unveiled a labial impacted and a rotation of approximately 90 degrees (horizontal impacted) on both central maxillary incisors.
DISCUSSION: The self-ligating bracket was installed and orthodontic traction aligned the affected tooth in the dental arch. To reach the labial surface of the impacted incisor, open surgical exposure by window excision of soft tissues with a laser was preferable due to the large bulge in the sulcus. Because self-ligating bracket systems employed modest pressures to position the maxillary right central incisor in the arch, the window surgical technique did not produce gingival scarring or increased clinical crown length.
CONCLUSION: The impacted upper central incisor was successfully treated using a collaborative interdisciplinary (surgical-orthodontic) approach, which resulted in a favorable aesthetic and functional outcome.
Fulltext Stearoyl CoA Desaturase Is Essential for Regulation of Endoplasmic Reticulum Homeostasis and Tumor Growth in Glioblastoma Cancer Stem Cells

Pinkham K, Park DJ, Hashemiaghdam A, Kirov AB, Adam I, Rosiak K, et al.

Stem Cell Reports, 2019 04 09;12(4):712-727.
PMID: 30930246 DOI: 10.1016/j.stemcr.2019.02.012

Inherent plasticity and various survival cues allow glioblastoma stem-like cells (GSCs) to survive and proliferate under intrinsic and extrinsic stress conditions. Here, we report that GSCs depend on the adaptive activation of ER stress and subsequent activation of lipogenesis and particularly stearoyl CoA desaturase (SCD1), which promotes ER homeostasis, cytoprotection, and tumor initiation. Pharmacological targeting of SCD1 is particularly toxic due to the accumulation of saturated fatty acids, which exacerbates ER stress, triggers apoptosis, impairs RAD51-mediated DNA repair, and achieves a remarkable therapeutic outcome with 25%-100% cure rate in xenograft mouse models. Mechanistically, divergent cell fates under varying levels of ER stress are primarily controlled by the ER sensor IRE1, which either promotes SCD1 transcriptional activation or converts to apoptotic signaling when SCD1 activity is impaired. Taken together, the dependence of GSCs on fatty acid desaturation presents an exploitable vulnerability to target glioblastoma.
Fulltext Mechanical and Thermal Properties of Montmorillonite-Reinforced Polypropylene/Rice Husk Hybrid Nanocomposites

Majeed K, Ahmed A, Abu Bakar MS, Indra Mahlia TM, Saba N, Hassan A, et al.

Polymers (Basel), 2019 Sep 25;11(10).
PMID: 31557811 DOI: 10.3390/polym11101557

In recent years, there has been considerable interest in the use of natural fibers as potential reinforcing fillers in polymer composites despite their hydrophilicity, which limits their widespread commercial application. The present study explored the fabrication of nanocomposites by melt mixing, using an internal mixer followed by a compression molding technique, and incorporating rice husk (RH) as a renewable natural filler, montmorillonite (MMT) nanoclay as water-resistant reinforcing nanoparticles, and polypropylene-grafted maleic anhydride (PP-g-MAH) as a compatibilizing agent. To correlate the effect of MMT delamination and MMT/RH dispersion in the composites, the mechanical and thermal properties of the composites were studied. XRD analysis revealed delamination of MMT platelets due to an increase in their interlayer spacing, and SEM micrographs indicated improved dispersion of the filler(s) from the use of compatibilizers. The mechanical properties were improved by the incorporation of MMT into the PP/RH system and the reinforcing effect was remarkable as a result of the use of compatibilizing agent. Prolonged water exposure of the prepared samples decreased their tensile and flexural properties. Interestingly, the maximum decrease was observed for PP/RH composites and the minimum was for MMT-reinforced and PP-g-MAH-compatibilized PP/RH composites. DSC results revealed an increase in crystallinity with the addition of filler(s), while the melting and crystallization temperatures remained unaltered. TGA revealed that MMT addition and its delamination in the composite systems improved the thermal stability of the developed nanocomposites. Overall, we conclude that MMT nanoclay is an effective water-resistant reinforcing nanoparticle that enhances the durability, mechanical properties, and thermal stability of composites.
Fulltext Role of optimization algorithms based fuzzy controller in achieving induction motor performance enhancement

Hannan MA, Ali JA, Hossain Lipu MS, Mohamed A, Ker PJ, Indra Mahlia TM, et al.

Nat Commun, 2020 Jul 30;11(1):3792.
PMID: 32733048 DOI: 10.1038/s41467-020-17623-5

Three-phase induction motors (TIMs) are widely used for machines in industrial operations. As an accurate and robust controller, fuzzy logic controller (FLC) is crucial in designing TIMs control systems. The performance of FLC highly depends on the membership function (MF) variables, which are evaluated by heuristic approaches, leading to a high processing time. To address these issues, optimisation algorithms for TIMs have received increasing interest among researchers and industrialists. Here, we present an advanced and efficient quantum-inspired lightning search algorithm (QLSA) to avoid exhaustive conventional heuristic procedures when obtaining MFs. The accuracy of the QLSA based FLC (QLSAF) speed control is superior to other controllers in terms of transient response, damping capability and minimisation of statistical errors under diverse speeds and loads. The performance of the proposed QLSAF speed controller is validated through experiments. Test results under different conditions show consistent speed responses and stator currents with the simulation results.
Recent progress in integrated fixed-film activated sludge process for wastewater treatment: A review

Waqas S, Bilad MR, Man Z, Wibisono Y, Jaafar J, Indra Mahlia TM, et al.

J Environ Manage, 2020 Aug 15;268:110718.
PMID: 32510449 DOI: 10.1016/j.jenvman.2020.110718

Integrated fixed-film activated sludge (IFAS) process is considered as one of the leading-edge processes that provides a sustainable solution for wastewater treatment. IFAS was introduced as an advancement of the moving bed biofilm reactor by integrating the attached and the suspended growth systems. IFAS offers advantages over the conventional activated sludge process such as reduced footprint, enhanced nutrient removal, complete nitrification, longer solids retention time and better removal of anthropogenic composites. IFAS has been recognized as an attractive option as stated from the results of many pilot and full scales studies. Generally, IFAS achieves >90% removals for combined chemical oxygen demand and ammonia, improves sludge settling properties and enhances operational stability. Recently developed IFAS reactors incorporate frameworks for either methane production, energy generation through algae, or microbial fuel cells. This review details the recent development in IFAS with the focus on the pilot and full-scale applications. The microbial community analyses of IFAS biofilm and floc are underlined along with the special emphasis on organics and nitrogen removals, as well as the future research perspectives.
Fulltext HLA-B*1502 and carbamazepine induced Stevens-Johnson syndrome/toxic epidermal necrolysis in Indonesia

Herlyani Khosama, Astri Budikayanti, Amy Hui Ping Khor, Lim, Kheng Seang, Ng, Ching-Ching, Indra G. Mansyur, et al.

Neurology Asia, 2017;22(2):113-116.
MyJurnal

Background & Objective: Association between HLA-B*1502 and carbamazepine-induced StevenJohnson
syndrome/toxic epidermal necrolysis (CBZ-SJS/TEN) was reported in many Southeast Asian
populations but not in Indonesian. The purpose of this study was to evaluate the association between
HLA-B*1502 andCBZ-SJS/TEN in an Indonesian population.

Methods: Patients with history of
CBZ-SJS/TEN are recruited as cases and those who tolerated CBZ as controls. HLA-B typing was
performed.

Results: We recruited 14 cases with CBZ-SJS/TEN and 53 controls. Positive HLA-B*1502
was found in 8 (57.1%) cases and 14 (26.4%) controls (OR 3.7, 95% CI 1.09-12.61, p=0.035).

Conclusion: HLA-B*1502 is associated with CBZ-SJS/TEN patients in Indonesian.
Fulltext Isolation and characterization of a novel rebaudioside M isomer from a bioconversion reaction of rebaudioside A and NMR comparison studies of rebaudioside M isolated from Stevia rebaudiana Bertoni and Stevia rebaudiana Morita

Prakash I, Bunders C, Devkota KP, Charan RD, Ramirez C, Priedemann C, et al.

Biomolecules, 2014;4(2):374-89.
PMID: 24970220 DOI: 10.3390/biom4020374

A minor product, rebaudioside M2 (2), from the bioconversion reaction of rebaudioside A (4) to rebaudioside D (3), was isolated and the complete structure of the novel steviol glycoside was determined. Rebaudioside M2 (2) is considered an isomer of rebaudioside M (1) and contains a relatively rare 1→6 sugar linkage. It was isolated and characterized with NMR (1H, 13C, COSY, HSQC-DEPT, HMBC, 1D-TOCSY, and NOESY) and mass spectral data. Additionally, we emphasize the importance of 1D and 2D NMR techniques when identifying complex steviol glycosides. Numerous NMR spectroscopy studies of rebaudioside M (1), rebaudioside D (3), and mixture of 1 and 3 led to the discovery that SG17 which was previously reported in literature, is a mixture of rebaudioside D (3), rebaudioside M (1), and possibly other related steviol glycosides.
Fulltext Facile preparation of carbon microcapsules containing phase-change material with enhanced thermal properties

Tahan Latibari S, Mehrali M, Mehrali M, Mahlia TM, Metselaar HS

ScientificWorldJournal, 2014;2014:379582.
PMID: 25054179 DOI: 10.1155/2014/379582

This study describes the hydrothermal synthesis of a novel carbon/palmitic acid (PA) microencapsulated phase change material (MEPCM). The field emission scanning electron microscopy (FESEM) and high resolution transmission electron microscopy (HRTEM) images confirm that spherical capsules of uniform size were formed with a mean diameter of 6.42 μm. The melting and freezing temperature were found to be slightly lower than those of pure PA with little undercooling. The composite retained 75% of the latent heat of pure PA. Thermal stability of the MEPCM was found to be better than that of pure PA. The thermal conductivity of MEPCM was increased by as much as 41% at 30°C. Due to its good thermal properties and chemical and mechanical stability, the carbon/PA MEPCM displays a good potential for thermal energy storage systems.
Fulltext Insecticide resistance and its underlying mechanisms in field populations of Aedes aegypti adults (Diptera: Culicidae) in Singapore

Koou SY, Chong CS, Vythilingam I, Lee CY, Ng LC

Parasit Vectors, 2014;7:471.
PMID: 25301032 DOI: 10.1186/s13071-014-0471-0

In Singapore, dose-response bioassays of Aedes aegypti (L.) adults have been conducted, but the mechanisms underlying resistance to insecticides remain unclear. In this study, we evaluated insecticide resistance and its underlying mechanism in field populations of Ae. aegypti adults.
Pyrethroid resistance in Aedes aegypti larvae (Diptera: Culicidae) from Singapore

Koou SY, Chong CS, Vythilingam I, Ng LC, Lee CY

J Med Entomol, 2014 Jan;51(1):170-81.
PMID: 24605467

We report the first comprehensive insecticide susceptibility status ofAedes aegypti (L.) larvae from Singapore. The study indicated that Ae. aegypti is susceptible to temephos, although resistance (RR50 = 1.29-4.43-fold) couldbe developing. Of high concern is the detection of moderate to high resistance to permethrin (RR50 = 29-47-fold) and etofenprox (RR50 = 14-34-fold). Biolarvicide Bacillus thuringiensis israelensis (Bti) remains effective. The insecticide susceptibility profile of Ae. aegypti larvae was found to be homogenous among the different sites studied across the island city. The addition of synergists piperonyl butoxide, S,S,S,-tributyl phosphorotrithioate, and triphenyl phosphate generally failed to enhance the toxicity of the insecticides investigated, suggesting an insignificant role of metabolic-based resistance, and a possible involvement of target site resistance. Further biochemical investigation of specific metabolic enzyme activities suggested that detoxifying enzymes, mono-oxygenases, esterases, glutathione S-transferases, and altered acetylcholinesterases, generally did not contribute to the resistance observed. This study clearly demonstrated that pyrethroid resistance is widespread among Ae. aegypti population and lowered susceptibility to organophosphates is developing.
Fulltext Colonization of Anopheles cracens: a malaria vector of emerging importance

Amir A, Sum JS, Lau YL, Vythilingam I, Fong MY

Parasit Vectors, 2013;6:81.
PMID: 23537404 DOI: 10.1186/1756-3305-6-81

Anopheles cracens has been incriminated as a vector for the simian malaria parasite, Plasmodium knowlesi, that is the fifth Plasmodium species infecting humans. Little experimental data exists on this mosquito species due to the lack of its availability in laboratories.
Entomologic investigation of Plasmodium knowlesi vectors in Kuala Lipis, Pahang, Malaysia

Jiram AI, Vythilingam I, NoorAzian YM, Yusof YM, Azahari AH, Fong MY

Malar J, 2012;11:213.
PMID: 22727041

The first natural infection of Plasmodium knowlesi in humans was recorded in 1965 in peninsular Malaysia. Extensive research was then conducted and it was postulated that it was a rare incident and that simian malaria will not be easily transmitted to humans. However, at the turn of the 21st century, knowlesi malaria was prevalent throughout Southeast Asia and is life threatening. Thus, a longitudinal study was initiated to determine the vectors, their seasonal variation and preference to humans and macaques.
Fulltext Recent surveys in the forests of Ulu Segama Malua, Sabah, Malaysia, show that orang-utans (P. p. morio) can be maintained in slightly logged forests

Ancrenaz M, Ambu L, Sunjoto I, Ahmad E, Manokaran K, Meijaard E, et al.

PLoS One, 2010;5(7):e11510.
PMID: 20634974 DOI: 10.1371/journal.pone.0011510

Today the majority of wild great ape populations are found outside of the network of protected areas in both Africa and Asia, therefore determining if these populations are able to survive in forests that are exploited for timber or other extractive uses and how this is managed, is paramount for their conservation.
Fulltext Plasmodium knowlesi malaria in Vietnam: some clarifications

Van den Eede P, Vythilingam I, Ngo DT, Nguyen VH, Le XH, D'Alessandro U, et al.

Malar J, 2010;9:20.
PMID: 20082717 DOI: 10.1186/1475-2875-9-20

A recently published comment on a report of Plasmodium knowlesi infections in Vietnam states that this may not accurately represent the situation in the study area because the PCR primers used may cross-hybridize with Plasmodium vivax. Nevertheless, P. knowlesi infections have been confirmed by sequencing. In addition, a neighbour-joining tree based on the 18S S-Type SSUrRNA gene shows that the Vietnamese samples clearly cluster with the P. knowlesi isolates identified in Malaysia and are distinct from the corresponding P. vivax sequences. All samples came from asymptomatic individuals who did not consult for fever during the months preceding or following the survey, indicating that asymptomatic P. knowlesi infections occur in this population, although this does not exclude the occurrence of symptomatic cases. Large-scale studies to determine the extent and the epidemiology of P. knowlesi malaria in Vietnam are further needed.
Liquid-gas boundary catalysis by using gold/polystyrene-coated hollow titania

Ran NH, Yuliati L, Lee SL, Mahlia TM, Nur H

J Colloid Interface Sci, 2013 Mar 15;394:490-7.
PMID: 23380399 DOI: 10.1016/j.jcis.2012.12.045

A microparticle material of gold/polystyrene-coated hollow titania was successfully synthesized. The synthesis steps involved hydrothermal synthesis of a carbon sphere from sucrose as a template, coating of the carbon sphere with titania, removal of the carbon sphere to produce hollow titania, followed by coating of polystyrene on the surface of hollow titania and then attachment of gold nanoparticles. It has been demonstrated that this material can float on water due to its low density and it is a potential catalyst for liquid-gas boundary catalysis in oxidation of benzyl alcohol by using molecular oxygen.
Chikungunya Virus Infection of Aedes Mosquitoes

Wong HV, Chan YF, Sam IC, Sulaiman WY, Vythilingam I

Methods Mol Biol, 2016;1426:119-28.
PMID: 27233266 DOI: 10.1007/978-1-4939-3618-2_11

In vivo infection of mosquitoes is an important method to study and characterize arthropod-borne viruses. Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that is transmitted primarily by Aedes mosquitoes. In this chapter, we describe a protocol for infection of CHIKV in two species of Aedes mosquitoes, Aedes aegypti and Aedes albopictus, together with the isolation of CHIKV in different parts of the infected mosquito such as midgut, legs, wings, salivary gland, head, and saliva. This allows the study of viral infection, replication and dissemination within the mosquito vector.

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