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Influence of alkaline hydrogen peroxide pre-hydrolysis on the isolation of microcrystalline cellulose from oil palm fronds

Owolabi AF, Haafiz MK, Hossain MS, Hussin MH, Fazita MR

Int J Biol Macromol, 2017 Feb;95:1228-1234.
PMID: 27836655 DOI: 10.1016/j.ijbiomac.2016.11.016

In the present study, microcrystalline cellulose (MCC) was isolated from oil palm fronds (OPF) using chemo-mechanical process. Wherein, alkaline hydrogen peroxide (AHP) was utilized to extract OPF fibre at different AHP concentrations. The OPF pulp fibre was then bleached with acidified sodium chlorite solution followed by the acid hydrolysis using hydrochloric acid. Several analytical methods were conducted to determine the influence of AHP concentration on thermal properties, morphological properties, microscopic and crystalline behaviour of isolated MCC. Results showed that the MCC extracted from OPF fibres had fibre diameters of 7.55-9.11nm. X-ray diffraction (XRD) analyses revealed that the obtained microcrystalline fibre had both celluloses I and cellulose II polymorphs structure, depending on the AHP concentrations. The Fourier transmission infrared (FTIR) analyses showed that the AHP pre-hydrolysis was successfully removed hemicelluloses and lignin from the OPF fibre. The crystallinity of the MCC was increased with the AHP concentrations. The degradation temperature of MCC was about 300°C. The finding of the present study showed that pre-treatment process potentially influenced the quality of the isolation of MCC from oil palm fronds.
Fulltext The Clinical Effectiveness of School Screening Programme for Idiopathic Scoliosis in Malaysia

Deepak AS, Ong JY, Choon D, Lee CK, Chiu CK, Chan C, et al.

Malays Orthop J, 2017 Mar;11(1):41-46.
PMID: 28435573 MyJurnal DOI: 10.5704/MOJ.1703.018

INTRODUCTION: There is no large population size study on school screening for scoliosis in Malaysia. This study is aimed to determine the prevalence rate and positive predictive value (PPV) of screening programme for adolescent idiopathic scoliosis.
MATERIALS AND METHODS: A total of 8966 voluntary school students aged 13-15 years old were recruited for scoliosis screening. Screening was done by measuring the angle of trunk rotation (ATR) on forward bending test (FBT) using a scoliometer. ATR of 5 degrees or more was considered positive. Positively screened students had standard radiographs done for measurement of the Cobb angle. Cobb angle of >10° was used to diagnose scoliosis. The percentage of radiological assessment referral, prevalence rate and PPV of scoliosis were then calculated.
RESULTS: Percentage of radiological assessment referral (ATR >5°) was 4.2% (182/4381) for male and 5.0% (228/4585) for female. Only 38.0% of those with ATR >5° presented for further radiological assessment. The adjusted prevalence rate was 2.55% for Cobb angle >10°, 0.59% for >20° and 0.12% for >40°. The PPV is 55.8% for Cobb angle >10°, 12.8% for >20° and 2.6% for > 40°.
CONCLUSIONS: This is the largest study of school scoliosis screening in Malaysia. The prevalence rate of scoliosis was 2.55%. The positive predictive value was 55.8%, which is adequate to suggest that the school scoliosis screening programme did play a role in early detection of scoliosis. However, a cost effectiveness analysis will be needed to firmly determine its efficacy.
Combine-ARMS: a rapid and cost-effective protocol for molecular characterization of beta-thalassemia in Malaysia

Tan KL, Tan JA, Wong YC, Wee YC, Thong MK, Yap SF

Genet. Test., 2001;5(1):17-22.
PMID: 11336396 DOI: 10.1089/109065701750168626

Beta-thalassemia major patients have chronic anemia and are dependent on blood transfusions to sustain life. Molecular characterization and prenatal diagnosis of beta3-thalassemia is essential in Malaysia because about 4.5% of the population are heterozygous carriers for beta-thalassemia. The high percentage of compound heterozygosity (47.62%) found in beta-thalassemia major patients in the Thalassaemia Registry, University of Malaya Medical Centre (UMMC), Malaysia, also supports a need for rapid, economical, and sensitive protocols for the detection of beta-thalassemia mutations. Molecular characterization of beta-thalassemia mutations in Malaysia is currently carried out using ARMS, which detects a single beta-thalassemia mutation per PCR reaction. We developed and evaluated Combine amplification refractory mutation system (C-ARMS) techniques for efficient molecular detection of two to three beta-thalassemia mutations in a single PCR reaction. Three C-ARMS protocols were evaluated and established for molecular characterization of common beta-thalassemia mutations in the Malay and Chinese ethnic groups in Malaysia. Two C-ARMS protocols (cd 41-42/IVSII #654 and -29/cd 71-72) detected the beta-thalassemia mutations in 74.98% of the Chinese patients studied. The CARMS for cd 41-42/IVSII #654 detected beta-thalassemia mutations in 72% of the Chinese families. C-ARMS for cd 41-42/IVSI #5/cd 17 allowed detection of beta-thalassemia mutations in 36.53% of beta-thalassemia in the Malay patients. C-ARMS for cd 41-42/IVSI #5/cd 17 detected beta-thalassemia in 45.54% of the Chinese patients. We conclude that C-ARMS with the ability to detect two to three mutations in a single reaction provides more rapid and cost-effective protocols for beta-thalassemia prenatal diagnosis and molecular analysis programs in Malaysia.
A single, large deletion accounts for all the beta-globin gene mutations in twenty families from Sabah (North Borneo), Malaysia. Mutation in brief no. 240. Online

Thong MK, Rudzki Z, Hall J, Tan JA, Chan LL, Yap SF

Hum Mutat, 1999;13(5):413.
PMID: 10338100 DOI: 10.1002/(SICI)1098-1004(1999)13:5<413::AID-HUMU15>

Beta-thalassemia major is one of the commonest genetic disorders in South-East Asia. The spectrum of beta-thalassemia mutations in the various ethnic sub-populations on the island of Borneo is unknown. We studied 20 Dusun children from the East Malaysian state of Sabah (North Borneo) with a severe beta-thalassemia major phenotype, using a combination of Southern analysis, polymerase chain reaction analysis and direct sequencing. We found the children to be homozygous for a large deletion, which has a 5' breakpoint at position -4279 from the cap site of the beta-globin gene (HBB) with the 3' breakpoint located in a L1 family of repetitive sequences at an unknown distance from the beta-globin gene. This was similar to a recent finding of a large deletion causing beta-thalassemia first described in unrelated beta-thalassemia heterozygotes of Filipino descent. This report describes the first 20 families with homozygosity of the deletion causing a severe phenotype. It provides the first information on the molecular epidemiology of beta-thalassemia in Sabah. This finding has implications for the population genetics and preventative strategies for beta-thalassemia major for nearly 300 million individuals in South-East Asia.
An outbreak of acute eosinophilic myositis attributed to human Sarcocystis parasitism

Arness MK, Brown JD, Dubey JP, Neafie RC, Granstrom DE

Am J Trop Med Hyg, 1999 Oct;61(4):548-53.
PMID: 10548287

Seven members of a 15-man U.S. military team that had operated in rural Malaysia developed an acute illness consisting of fever, myalgias, bronchospasm, fleeting pruritic rashes, transient lymphadenopathy, and subcutaneous nodules associated with eosinophilia, elevated erythrocyte sedimentation rate, and elevated levels of muscle creatinine kinase. Sarcocysts of an unidentified Sarcocystis species were found in skeletal muscle biopsies of the index case. Albendazole ameliorated symptoms in the index case; however, his symptoms persisted for more than 5 years. Symptoms in 5 other men were mild to moderate and self-limited, and 1 team member with laboratory abnormalities was asymptomatic. Of 8 team members tested for antibody to Sarcocystis, 6 were positive; of 4 with the eosinophilic myositis syndrome who were tested, all were positive. We attribute this outbreak of eosinophilic myositis to accidental tissue parasitism by Sarcocystis.
Pulmonary atresia with intact ventricular septum percutaneous radiofrequency-assisted valvotomy and balloon dilation versus surgical valvotomy and Blalock Taussig shunt

Alwi M, Geetha K, Bilkis AA, Lim MK, Hasri S, Haifa AL, et al.

J Am Coll Cardiol, 2000 Feb;35(2):468-76.
PMID: 10676696

We compared the result of radiofrequency (RF)-assisted valvotomy and balloon dilation with closed surgical valvotomy and Blalock Taussig (BT) shunt as primary treatment in selected patients with pulmonary atresia and intact ventricular septum (PA-IVS).
Hemoprotozoa and Anaplasma spp. in rodents and shrews of Bangladesh

Islam S, Rahman MK, Ferdous J, Rahman M, Akter S, Faraque MO, et al.

Trop Biomed, 2020 Dec 01;37(4):842-851.
PMID: 33612737 DOI: 10.47665/tb.37.4.842

Hemoprotozoans are important pathogens of animals and humans, among which some species have zoonotic significance. The prevalence of different hemoprotozoa and Anaplasma spp. in larger mammals have been reported from different regions of the world. But, very few studies have been conducted to estimate the prevalence of hemoprotozoa in rodents and shrews of South-East Asia. The study assessed the prevalence of hemoprotozoa and Anaplasma spp. in rodents and shrews of Bangladesh. Blood samples (n=451) were collected from rodents and shrews between June 2011 and June 2013 and July-December 2015 from 4 land gradients of Bangladesh. Giemsa-stained blood smears revealed that 13% of animals were harboring hemoprotozoa (4.7% Babesia spp., 0.67% Plasmodium spp.), and Anaplasma spp. (7.5%). The study may serve as a guide for future hemoparasitic research of rodents and shrews.
Molecularly imprinted polymer amalgamation on narrow-gapped Archimedean-spiral interdigitated electrodes: resistance to electrolyte fouling in acidic medium

Krishnan H, Gopinath SCB, Md Arshad MK, Zulhaimi HI, Ramanathan S

Mikrochim Acta, 2021 03 31;188(4):144.
PMID: 33791872 DOI: 10.1007/s00604-021-04794-1

A conventional photolithography technique was used to fabricate three types of Archimedean-spiral interdigitated electrodes (AIDEs) containing concentric interlocking electrodes with different electrode and gap sizes, i.e., 150 μm (D1), 100 μm (D2), and 50 μm (D3). The precision of the fabrication was validated by surface topography using scanning electron microscopy, high power microscopy, 3D-nano profilometry, and atomic force microscopy. These AIDEs were fabricated with a tolerance of ± 6 nm in dimensions. The insignificant current variation at the pico-ampere range for all bare AIDEs further proved the reproducibility of the device. The large gap sized AIDE (D1) is insensitive to acidic medium, whereas D2 and D3 are insensitive to alkali medium. D2 was the best with regard to its electrical characterization. Furthermore, uniformly synthesized molecularly imprinted polymer (MIP) nanoparticles prepared with human blood clotting factor IX and its aptamer were in the size range 140 to 160 nm, attached on the sensing surface and characterized. The average thickness of deposited MIP film was 1.7 μm. EDX data shows the prominent peaks for silicon and aluminum substrates as 61.79 and 22.52%, respectively. The MIP nanoparticles-deposited sensor surface was characterized by applying it in electrolyte solutions, and smooth curves with the current flow were observed at pH lower than 8 and discriminated against alkali media. This study provides a new MIP amalgamated AIDE with nano-gapped fingers enabling analysis of other biomaterials due to its operation in an ideal buffer range.
Histopathological and immunological changes in green mussel, Perna viridis, challenged with Vibrio alginolyticus

Laith AA, Ros-Amira MK, Sheikh HI, Effendy AWM, Najiah M

Fish Shellfish Immunol, 2021 Nov;118:169-179.
PMID: 34487829 DOI: 10.1016/j.fsi.2021.08.032

Understanding of pathogenicity and immunity is crucial in producing disease-resistant cultured mollusk varieties. This study aimed to isolate pathogenic Vibrio alginolyticus from naturally infected Perna viridis, and to determine histopathological and immunological changes after challenge test with the same bacteria. Biochemical tests and 16S rDNA identified the pathogen as V. alginolyticus (99%). Antibiotic susceptibility test showed ampicillin resistance of the pathogen. Pathogenicity assay was conducted by immersing P. viridis in 1.5 × 106 CFU mL-1V. alginolyticus for 60 min and observed for 5 days. Clinical signs, histopathological and immunological alterations were observed and monitored. Infected groups showed 60% mortality and decreased immunity factors, including total hemocyte count and lysozymes activity. Histopathological examination revealed pathological lesions in the hepatopancreas at 24 h post-challenge and hemocyte proliferation as part of a severe inflammatory reaction. Karyomegaly in the hepatopancreas tissue, concomitant with necrosis demolition of tubules cells, was also observed. V. alginolyticus was determined to be pathogenic to P. viridis, causing mortality as a result of multiple organ lesions and dysfunction in digestive gland and immune organs. This study demonstrated the role of histopathological and immunological parameters as potential biomarkers in assessing vibriosis caused by Vibrio species in green mussel, P. viridis.
Systematic review and meta-analysis of the prevalence of neuropathic-like pain and/or pain sensitization in people with knee and hip osteoarthritis

Zolio L, Lim KY, McKenzie JE, Yan MK, Estee M, Hussain SM, et al.

Osteoarthritis Cartilage, 2021 08;29(8):1096-1116.
PMID: 33971205 DOI: 10.1016/j.joca.2021.03.021

OBJECTIVE: To determine the prevalence of neuropathic-like pain (NP) and pain sensitization (PS) defined by self-report questionnaires in knee and hip osteoarthritis, and whether prevalence is potentially explained by disease-severity or affected joint.
DESIGN: MEDLINE, EMBASE, CINAHL were systematically searched (1990-April 2020) for studies describing the prevalence of NP and PS in knee and hip osteoarthritis using self-report questionnaires. Random-effects meta-analysis was performed. Statistical heterogeneity between studies and sub-groups (affected joint and population source as a proxy for disease severity) was assessed (I2 statistic and the Chi-squared test).
RESULTS: From 2,706 non-duplicated references, 39 studies were included (2011-2020). Thirty-six studies reported on knee pain and six on hip pain. For knee osteoarthritis, the pooled prevalence of NP was: using PainDETECT, possible NP(score ≥13) 40% (95%CI 32-48%); probable NP(score >18) 20% (95%CI 15-24%); using Self-Report Leeds Assessment of Neuropathic Symptoms and Signs, 32% (95%CI 26-38%); using Douleur Neuropathique (DN4) 41% (95% CI 24-59%). The prevalence of PS using Central Sensitization Inventory (CSI) was 36% (95% CI 12-59%). For hip osteoarthritis, the pooled prevalence of NP was: using PainDETECT, possible NP 29% (95%CI 22-37%%); probable NP 9% (95%CI 6-13%); using DN4 22% (95%CI 12-31%) in one study. The prevalence of possible NP pain was higher at the knee (40%) than the hip (29%) (difference 11% (95% CI 0-22%), P = 0.05).
CONCLUSIONS: Using self-report questionnaire tools, NP was more prevalent in knee than hip osteoarthritis. The prevalence of NP in knee and hip osteoarthritis were similar for each joint regardless of study population source or tool used. Whether defining NP using self-report questionnaires enables more effective targeted therapy in osteoarthritis requires investigation.
Fulltext Impact of COVID-19 on Clinical Practices during Lockdown: A pan India Survey of Orthopaedic Surgeons

Jain VK, Upadhyaya GK, Iyengar KP, Patralekh MK, Lal H, Vaishya R

Malays Orthop J, 2021 Mar;15(1):55-62.
PMID: 33880149 DOI: 10.5704/MOJ.2103.009

Introduction: The social lockdown measures imposed to contain the COVID-19 pandemic, have had profound effects on the healthcare systems across the world and India has been no exception to it. The study was aimed to evaluate the impact of COVID-19 on orthopaedic practice in India during the lockdown period and assess the preparedness of orthopaedic surgeons for resuming clinical practice after the initial lockdown was lifted.
Materials and Methods: An online survey of 35 questions was conducted to evaluate impact on (i) general orthopaedic practice (ii) hospital protocols (iii) out-patient practice (iv) surgical practice (v) personal protective equipment (PPE) use and (vi) post-lockdown preparedness.
Results: A total number of 588 practising orthopaedic surgeons from India completed the survey. Majority (88.3%) found severe impact (>50%) on trauma surgery and non-trauma surgery with significant reduction in out -patient attendance compared to corresponding time in 2019. There were significant changes made in individual hospital protocols (91.7 %). Appropriate required PPE was available in majority of the hospitals (74.3%). No remodelling or upgrading of the existing operating theatre infrastructure was done by most surgeons (89.5%).
Conclusion: This pan India survey of orthopaedic surgeons has indicated that COVID-19 has had a profound impact on their outpatient and surgical trauma and non-trauma practice, due to the lockdown and resulted in significant changes to hospital protocols. Preparedness to resume clinical and surgical practice was associated with anxiety in two-thirds of the respondents. Majority of the orthopaedic practitioners felt that they would continue to conduct pre-operative COVID-19 screening and use PPE even after the lockdown is over.
Fulltext Aptasensing nucleocapsid protein on nanodiamond assembled gold interdigitated electrodes for impedimetric SARS-CoV-2 infectious disease assessment

Ramanathan S, Gopinath SCB, Ismail ZH, Md Arshad MK, Poopalan P

Biosens Bioelectron, 2022 Feb 01;197:113735.
PMID: 34736114 DOI: 10.1016/j.bios.2021.113735

In an aim of developing portable biosensor for SARS-CoV-2 pandemic, which facilitates the point-of-care aptasensing, a strategy using 10 μm gap-sized gold interdigitated electrode (AuIDE) is presented. The silane-modified AuIDE surface was deposited with ∼20 nm diamond and enhanced the detection of SARS-CoV-2 nucleocapsid protein (NCP). The characteristics of chemically modified diamond were evidenced by structural analyses, revealing the cubic crystalline nature at (220) and (111) planes as observed by XRD. XPS analysis denotes a strong interaction of carbon element, composed ∼95% as seen in EDS analysis. The C-C, CC, CO, CN functional groups were well-refuted from XPS spectra of carbon and oxygen elements in diamond. The interrelation between elements through FTIR analysis indicates major intrinsic bondings at 2687-2031 cm-1. The aptasensing was evaluated through electrochemical impedance spectroscopy measurements, using NCP spiked human serum. With a good selectivity the lower detection limit was evidenced as 0.389 fM, at a linear detection range from 1 fM to 100 pM. The stability, and reusability of the aptasensor were demonstrated, showing ∼30% and ∼33% loss of active state, respectively, after ∼11 days. The detection of NCP was evaluated by comparing anti-NCP aptamer and antibody as the bioprobes. The determination coefficients of R2 = 0.9759 and R2 = 0.9772 were obtained for aptamer- and antibody-based sensing, respectively. Moreover, the genuine interaction of NCP aptamer and protein was validated by enzyme linked apta-sorbent assay. The aptasensing strategy proposed with AuIDE/diamond enhanced sensing platform is highly recommended for early diagnosis of SARS-CoV-2 infection.
Fulltext An intelligent decision support system for crop yield prediction using hybrid machine learning algorithms

Anbananthen KSM, Subbiah S, Chelliah D, Sivakumar P, Somasundaram V, Velshankar KH, et al.

F1000Res, 2021;10:1143.
PMID: 34987773 DOI: 10.12688/f1000research.73009.1

Background: In recent times, digitization is gaining importance in different domains of knowledge such as agriculture, medicine, recommendation platforms, the Internet of Things (IoT), and weather forecasting. In agriculture, crop yield estimation is essential for improving productivity and decision-making processes such as financial market forecasting, and addressing food security issues. The main objective of the article is to predict and improve the accuracy of crop yield forecasting using hybrid machine learning (ML) algorithms. Methods: This article proposes hybrid ML algorithms that use specialized ensembling methods such as stacked generalization, gradient boosting, random forest, and least absolute shrinkage and selection operator (LASSO) regression. Stacked generalization is a new model which learns how to best combine the predictions from two or more models trained on the dataset. To demonstrate the applications of the proposed algorithm, aerial-intel datasets from the github data science repository are used. Results: Based on the experimental results done on the agricultural data, the following observations have been made. The performance of the individual algorithm and hybrid ML algorithms are compared using cross-validation to identify the most promising performers for the agricultural dataset. The accuracy of random forest regressor, gradient boosted tree regression, and stacked generalization ensemble methods are 87.71%, 86.98%, and 88.89% respectively. Conclusions: The proposed stacked generalization ML algorithm statistically outperforms with an accuracy of 88.89% and hence demonstrates that the proposed approach is an effective algorithm for predicting crop yield. The system also gives fast and accurate responses to the farmers.
Fulltext Pre-operative Halo-Pelvic Traction for Neurofibromatosis Patients with Severe Proximal Thoracic Spinal Deformity: Indications and Early Treatment Outcome

Chung WH, Mihara Y, Toyat SS, Chiu CK, Hasan MS, Saw A, et al.

Malays Orthop J, 2021 Nov;15(3):99-107.
PMID: 34966502 DOI: 10.5704/MOJ.2111.015

Introduction: To report the indications and early treatment outcomes of pre-operative halo-pelvic traction in patients with neurofibromatosis associated with severe proximal thoracic (PT) spinal deformity.
Materials and methods: We reviewed four patients with neurofibromatosis with severe PT spinal deformity. Case 1, a 16-year-old male presented with severe PT kyphoscoliosis (scoliosis: 89°, kyphosis: 124°) and thoracic myelopathy. Case 2 was a 14-year-old, skeletally immature male who presented with a PT lordoscoliosis (scoliosis: 85°). Case 3, a 13-year-old male, presented with severe PT kyphoscoliosis (scoliosis: 100°, kyphosis: 95°). Case 4, a 35-year-old gentleman, presented with severe PT kyphoscoliosis (scoliosis: 113°, kyphosis: 103°) and thoracic myelopathy. All patients underwent pre-operative halo-pelvic traction. After a period of traction, all patients underwent posterior spinal fusion (PSF) with autologous bone grafts (local and fibula bone grafts) and recombinant human bone morphogenetic protein-2 (rhBMP-2).
Results: Both patients with thoracic myelopathy regained near normal neurological status after halo-pelvic traction. Following traction, the scoliosis correction rate (CR) ranged from 18.0% to 38.9%, while the kyphosis CR ranged from 14.6% to 37.1%. Following PSF, the scoliosis CR ranged from 24.0% to 58.8%, while the kyphosis CR ranged from 29.1% to 47.4%. The total distraction ranged from 50-70mm. Duration of distraction ranged from 26-95 days. The most common complication encountered during halo-pelvic traction was pin-related e.g. pin tract infection, pin loosening and migration, osteomyelitis, and halo-pelvic strut breakage. No patients had cranial nerve palsies or neurological worsening.
Conclusion: Pre-operative correction of severe PT spinal deformities could be performed safely and effectively with the halo-pelvic device prior to definitive surgery.
Fulltext Enhancement of Temperature Fluorescence Brightness of Zn@Si Core-Shell Quantum Dots Produced via a Unified Strategy

Almomani MS, Ahmed NM, Rashid M, Ali MKM, Akhdar H, Aldaghri O, et al.

Nanomaterials (Basel), 2021 Nov 22;11(11).
PMID: 34835923 DOI: 10.3390/nano11113158

Despite many dedicated efforts, the fabrication of high-quality ZnO-incorporated Zinc@Silicon (Zn@Si) core-shell quantum dots (ZnSiQDs) with customized properties remains challenging. In this study, we report a new record for the brightness enhancement of ZnSiQDs prepared via a unified top-down and bottom-up strategy. The top-down approach was used to produce ZnSiQDs with uniform sizes and shapes, followed by the bottom-up method for their re-growth. The influence of various NH4OH contents (15 to 25 µL) on the morphology and optical characteristics of ZnSiQDs was investigated. The ZnSiQDs were obtained from the electrochemically etched porous Si (PSi) with Zn inclusion (ZnPSi), followed by the electropolishing and sonication in acetone. EFTEM micrographs of the samples prepared without and with NH4OH revealed the existence of spherical ZnSiQDs with a mean diameter of 1.22 to 7.4 nm, respectively. The emission spectra of the ZnSiQDs (excited by 365 nm) exhibited bright blue, green, orange-yellow, and red luminescence, indicating the uniform morphology related to the strong quantum confinement ZnSiQDs. In addition, the absorption and emission of the ZnSiQDs prepared with NH4OH were enhanced by 198.8% and 132.6%, respectively. The bandgap of the ZnSiQDs conditioned without and with NH4OH was approximately 3.6 and 2.3 eV, respectively.
Fulltext Thin-Walled Cylindrical Shell Storage Tank under Blast Impacts: Finite Element Analysis

Al-Yacouby AM, Hao LJ, Liew MS, Ratnayake RMC, Samarakoon SMK

Materials (Basel), 2021 Nov 22;14(22).
PMID: 34832500 DOI: 10.3390/ma14227100

Thin-walled cylindrical shell storage tanks are pressure vessels in which the walls of the vessel have a thickness that is much smaller than the overall size of the vessel. These types of structures have global applications in various industries, including oil refineries and petrochemical plants. However, these storage tanks are vulnerable to fire and explosions. Therefore, a parametric study using numerical simulation was carried out, considering the internal liquid level, wall thickness, material yield strength, constraint conditions, and blast intensity, with a diameter of 100 m and height of 22.5 m under different blast loads using the finite element analysis method. The thickness of the tank wall is varied as 10 mm, 20 mm, 30 mm, and 40 mm, while the fill level of internal fluid is varied as 25, 50, 75, and 100%. The blast simulation was conducted using LS-DYNA software. The numerical results are then compared with analytical results. The effects of blast intensity, standoff distance, wall thickness, and fill level of internal fluid on the structural behaviour of the storage tank were investigated and discussed.
Fulltext Acoustic emission corrosion feature extraction and severity prediction using hybrid wavelet packet transform and linear support vector classifier

May Z, Alam MK, Nayan NA, Rahman NAA, Mahmud MS

PLoS One, 2021;16(12):e0261040.
PMID: 34914761 DOI: 10.1371/journal.pone.0261040

Corrosion in carbon-steel pipelines leads to failure, which is a major cause of breakdown maintenance in the oil and gas industries. The acoustic emission (AE) signal is a reliable method for corrosion detection and classification in the modern Structural Health Monitoring (SHM) system. The efficiency of this system in detection and classification mainly depends on the suitable AE features. Therefore, many feature extraction and classification methods have been developed for corrosion detection and severity assessment. However, the extraction of appropriate AE features and classification of various levels of corrosion utilizing these extracted features are still challenging issues. To overcome these issues, this article proposes a hybrid machine learning approach that combines Wavelet Packet Transform (WPT) integrated with Fast Fourier Transform (FFT) for multiresolution feature extraction and Linear Support Vector Classifier (L-SVC) for predicting corrosion severity levels. A Laboratory-based Linear Polarization Resistance (LPR) test was performed on carbon-steel samples for AE data acquisition over a different time span. AE signals were collected at a high sampling rate with a sound well AE sensor using AEWin software. Simulation results show a linear relationship between the proposed approach-based extracted AE features and the corrosion process. For multi-class problems, three corrosion severity stages have been made based on the corrosion rate over time and AE activity. The ANOVA test results indicate the significance within and between the feature-groups where F-values (F-value>1) rejects the null hypothesis and P-values (P-value<0.05) are less than the significance level. The utilized L-SVC classifier achieves higher prediction accuracy of 99.0% than the accuracy of other benchmarked classifiers. Findings of our proposed machine learning approach confirm that it can be effectively utilized for corrosion detection and severity assessment in SHM applications.
Fulltext Increased yield performance of mutation induced Soybean genotypes at varied agro-ecological conditions

Bhuiyan MSH, Malek MA, Emon RM, Khatun MK, Khandaker MM, Alam MA

Braz J Biol, 2022;84:e255235.
PMID: 35019108 DOI: 10.1590/1519-6984.255235

In soybean breeding program, continuous selection pressure on traits response to yield created a genetic bottleneck for improvements of soybean through hybridization breeding technique. Therefore an initiative was taken to developed high yielding soybean variety applying mutation breeding techniques at Plant Breeding Division, Bangladesh Institute of Nuclear Agriculture (BINA), Bangladesh. Locally available popular cultivar BARI Soybean-5 was used as a parent material and subjected to five different doses of Gamma ray using Co60. In respect to seed yield and yield attributing characters, twelve true breed mutants were selected from M4 generation. High values of heritability and genetic advance with high genotypic coefficient of variance (GCV) for plant height, branch number and pod number were considered as favorable attributes for soybean improvement that ensure expected yield. The mutant SBM-18 obtained from 250Gy provided stable yield performance at diversified environments. It provided maximum seed yield of 3056 kg ha-1 with highest number of pods plant-1 (56). The National Seed Board of Bangladesh (NSB) eventually approved SBM-18 and registered it as a new soybean variety named 'Binasoybean-5' for large-scale planting because of its superior stability in various agro-ecological zones and consistent yield performance.
Calibrating different sounds for sound therapy: A general guide

Amirullah NA, Rahmat S, Dzulkarnain AAA, Maamor N, Jamaludin MKA, Che Azemin MZ

Med J Malaysia, 2022 Jan;77(1):12-19.
PMID: 35086989

INTRODUCTION: Sound therapy is one of the complementary or alternative interventions for various populations. The intensity of the sounds for sound therapy needs to be properly calibrated to ensure their accuracy and effectiveness. This paper aims to provide a general guideline for calibrating sound files using free software, specifically Audacity®.
MATERIALS AND METHODS: Six sounds (broadband noise, rain, ocean, waterfall, Quranic chapters Al-Fatihah, and Yasin recitations) were calibrated at the intensity levels of 45, 50, 55, 60, 65, 70, 75, and 80dBA. The sounds were delivered through a pair of Sennheiser HD 280 Pro headphones connected to the Sound Blaster X-Fi Surround 5.1 Pro sound card. The long-term average of the sound pressure level over the time of recording (LAseq) was recorded using the 3M SoundPro Class 1 1/3 Octave RTA sound level meter (SLM). The desired intensity levels were obtained by making adjustments to the sound files via the Audacity® software.
RESULTS: All sound files were calibrated at the targeted levels as verified by the value of LAseq.
CONCLUSIONS: Calibration of audio files can be done using a free/open-source software, as all six sound files were successfully calibrated at the targeted levels of 45, 50, 55, 60, 65, 70, 75, and 80dBA. The calibration steps provided in this paper can be easily applied by other researchers for similar purposes, with precautions when calibrating at low levels.
Spatial distribution of copepods along the salinity gradient of Perai river estuary, Penang, Malaysia

Johan I, Maznah WO, Mashhor M, Abu Hena MK, Amin SM

Pak J Biol Sci, 2012 Jul 01;15(13):647-52.
PMID: 24218935

Investigation on copepod communities in Perai river estuary was conducted from November 2005 to May 2006. Five stations were established for monthly sampling and were located from the river mouth to the upper reaches of the river. Copepod samples were collected from vertical tows using a standard zooplankton net. The Perai river estuary was slightly stratified and salinity decreases significantly from the mouth of the river towards the upper reaches of the river. A total of 28 species of copepods were recorded and comprised of 14 families, Paracalanidae, Oithonidae, Corycaeidae, Acartiidae, Calanidae, Centropagidae, Eucalanidae, Pontellidae, Pseudodiaptomidae, Tortanidae, Ectinosomatidae, Euterpinidae, Clausidiidae and Cyclopidae. A total of 10 species showed high positive affiliation towards salinity (R > 0.60), Acartia spinicauda, Euterpina acutifrons, Microsetella norvegica, Oithona nana, Oithona simplex, Paracalanus crassirostris, Paracalanus elegans, Paracalanus parvus, Pseudodiaptomus sp. and Hemicyclops sp. The copepod species Pseudodiaptomus dauglishi were negatively affiliated towards salinity (R = -0.71). The copepod assemblages classified into two distinct groups according to salinity regimes, euryhaline-polyhaline group (25 marine affiliated species) and oligohaline-mesohaline group (3 freshwater affiliated species).

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