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Fulltext Surface Characteristics and Catalytic Activity of Copper Deposited Porous Silicon Powder

Halim MYA, Tan WL, Bakar NHHA, Bakar MA

Materials (Basel), 2014 Dec 04;7(12):7737-7751.
PMID: 28788272 DOI: 10.3390/ma7127737

Porous structured silicon or porous silicon (PS) powder was prepared by chemical etching of silicon powder in an etchant solution of HF: HNO₃: H₂O (1:3:5 v/v). An immersion time of 4 min was sufficient for depositing Cu metal from an aqueous solution of CuSO₄ in the presence of HF. Scanning electron microscopy (SEM) analysis revealed that the Cu particles aggregated upon an increase in metal content from 3.3 wt% to 9.8 wt%. H₂-temperature programmed reduction (H₂-TPR) profiles reveal that re-oxidation of the Cu particles occurs after deposition. Furthermore, the profiles denote the existence of various sizes of Cu metal on the PS. The Cu-PS powders show excellent catalytic reduction on the p-nitrophenol regardless of the Cu loadings.
Fulltext Parallel operated hybrid Arithmetic-Salp swarm optimizer for optimal allocation of multiple distributed generation units in distribution networks

Anjum ZM, Said DM, Hassan MY, Leghari ZH, Sahar G

PLoS One, 2022;17(4):e0264958.
PMID: 35417475 DOI: 10.1371/journal.pone.0264958

The installation of Distributed Generation (DG) units in the Radial Distribution Networks (RDNs) has significant potential to minimize active power losses in distribution networks. However, inaccurate size(s) and location(s) of DG units increase power losses and associated Annual Financial Losses (AFL). A comprehensive review of the literature reveals that existing analytical, metaheuristic and hybrid algorithms employed on DG allocation problems trap in local or global optima resulting in higher power losses. To address these limitations, this article develops a parallel hybrid Arithmetic Optimization Algorithm and Salp Swarm Algorithm (AOASSA) for the optimal sizing and placement of DGs in the RDNs. The proposed parallel hybrid AOASSA enables the mutual benefit of both algorithms, i.e., the exploration capability of the SSA and the exploitation capability of the AOA. The performance of the proposed algorithm has been analyzed against the hybrid Arithmetic Optimization Algorithm Particle Swarm Optimization (AOAPSO), Salp Swarm Algorithm Particle Swarm Optimization (SSAPSO), standard AOA, SSA, and Particle Swarm Optimization (PSO) algorithms. The results obtained reveals that the proposed algorithm produces quality solutions and minimum power losses in RDNs. The Power Loss Reduction (PLR) obtained with the proposed algorithm has also been validated against recent analytical, metaheuristic and hybrid optimization algorithms with the help of three cases based on the number of DG units allocated. Using the proposed algorithm, the PLR and associated AFL reduction of the 33-bus and 69-bus RDNs improved to 65.51% and 69.14%, respectively. This study will help the local distribution companies to minimize power losses and associated AFL in the long-term planning paradigm.
Fulltext Determination of ethanol, isopropyl alcohol and methanol in alcohol-based hand sanitiser to ensure product quality, safety and efficacy

Nisbar ND, Jamal Khair SK, Bujang NB, Mohd Yusop AY

Sci Rep, 2023 Jun 10;13(1):9478.
PMID: 37301842 DOI: 10.1038/s41598-023-36283-1

The Coronavirus Disease-2019 (COVID-19) outbreak is an unprecedented global pandemic, sparking grave public health emergencies. One of the measures to reduce COVID-19 transmissions recommended by the World Health Organization is hand hygiene, i.e., washing hands with soap and water or disinfecting them using an alcohol-based hand sanitiser (ABHS). Unfortunately, competing ABHSs with unknown quality, safety, and efficacy thrived, posing yet another risk to consumers. This study aims to develop, optimise, and validate a gas chromatography-mass spectrometry (GC-MS)-based analytical method to simultaneously identify and quantify ethanol or isopropyl alcohol as the active ingredient in ABHS, with simultaneous determination of methanol as an impurity. The GC-MS was operated in Electron Ionisation mode, and Selected Ion Monitoring was chosen as the data acquisition method for quantitation. The analytical method was validated for liquid and gel ABHSs, covering the specificity, linearity and range, accuracy, and precisions, including the limit of detection and the limit of quantitation. The specificity of each target analyte was established using the optimised chromatographic separation with unique quantifier and qualifier ions. The linearity was ascertained with a coefficient of determination (r2) of > 0.9994 over the corresponding specification range. Respectively, the accuracy and precisions were satisfactory within 98.99 to 101.09% and
The relationship between carbon dioxide flux and environmental parameters at a tropical coastal sea on different timescales

Yusup Y, Swesi AE, Sigid MF, Almdhun HM, Jamshidi EJ

Mar Pollut Bull, 2023 Aug;193:115106.
PMID: 37302202 DOI: 10.1016/j.marpolbul.2023.115106

This paper analyzes CO2 flux between the atmosphere and a tropical coastal sea using the eddy covariance technique. Coastal carbon dioxide flux studies are limited, particularly in tropical regions. Data was collected from the study site in Pulau Pinang, Malaysia, since 2015. The research found that the site is a moderate CO2 sink and experiences seasonal monsoonal changes that affect its carbon-sink or carbon-source capability. The analysis showed that the coastal sea systematically shifted from being a carbon-sink at night to a weak carbon-source during the day possibly due to cause by the synergistic influence of wind speed and seawater temperature. The CO2 flux are also influenced by small-scale, unpredictable winds, limited fetch, developing waves, and high-buoyancy conditions caused by low wind speeds and an unstable surface layer. Furthermore, it exhibited a linear relationship with wind speed. In stable conditions, the flux was influenced by wind speed and drag coefficient, while in unstable conditions, it was mostly controlled by friction velocity and atmospheric stability. These findings could improve our understanding of the critical factors that drive CO2 flux at the tropical coast.
A Systematic Review on Clinico-Aetiopathological Trends of Nasopharyngeal Cancer in Asia

Haji Noor Mohamed NM, S M N Mydin RB, Che Halim H, Musa MY

Indian J Otolaryngol Head Neck Surg, 2023 Dec;75(4):4151-4157.
PMID: 37974670 DOI: 10.1007/s12070-023-03905-z

BACKGROUND: Nasopharyngeal cancer (NPC) is a type of malignancy that is highly prevalent in Asian countries. Therefore, an understanding between NPC epidemiological trend, the clinico-pathological and aetiological profiles are needed. This systematic review focuses on asian countries demographic and clinico-pathological presentation reported in 9982 NPC cases diagnosed from the year 2010 to 2021.
METHODOLOGY: Data were extracted from databases, such as PubMed, Springer Link, Science Direct, Google Scholar and general search engines, by using pre-determined keywords (e.g. clinico-pathological data, age, sex, tumour stage, nasopharyngeal cancer, nasopharyngeal carcinoma, naso-pharynx and cancer in Asia).
RESULTS AND CONCLUSION: Findings from our systematic review shows that from 2010 to 2021, males in age range below 50 years old are at a higher risk of developing NPC in Asia. NPC is mostly diagnosed at advanced stage in Asia, which is likely due to the deep-seated location of the cancer. Type III NPC and EBV proteins (EBNA1 and LMP2A) are frequently associated with reported EBV-positive NPC cases in Asian countries. Meanwhile, NPC type I, II, and III are associated with EBV-negative NPC cases in Asia. Human leucocyte antigen (HLA) alleles (A2, B27, and B46) are frequently present in reported EBV-negative NPC cases in Asia. In Asia, males below 50 years old are more prone to NPC and often diagnosed at late stage. EBV-positive and EBV-negative NPC in Asia have unique histological profiles. Systemic approach of this study may help to provide better knowledge on reported NPC cases especially on the risk factors and clinical presentation focusing in Asian countries.
Fulltext Gut Microbiota Composition in the First and Third Trimester of Pregnancy among Malay Women is Associated with Body Mass Index: A Pilot Study

Abdullah B, Idorus MY, Daud S, Aazmi S, Pillai TK, Zain ZM

Malays J Med Sci, 2023 Feb;30(1):116-128.
PMID: 36875193 DOI: 10.21315/mjms2023.30.1.10

BACKGROUND: This study has analysed the pattern of gut microbiota during the first and third trimesters among pregnant Malay women.
METHODS: This was a pilot prospective observational study involving 12 pregnant Malay women without any endocrine disorders and on neither antibiotics nor probiotics. Demographic details and anthropometric measurements were obtained, and the faecal 16S ribosomal ribonucleic acid (rRNA) metagenome microbiota of the first and third trimesters (T1 and T3) were analysed. Univariate and multivariate statistics, partial least squares discriminant analysis (PLSDA) and Kendall rank correlation testing were used to identify key genera and associations with pregnancy trimester and body mass index (BMI).
RESULTS: The most abundant phyla were Bacteroidetes, Firmicutes, Proteobacteria and Actinobacteria, with significant differences in composition at the genus level demonstrated between T1 and T3. Sequencing showed a statistically significant difference in beta diversity between normal and abnormal BMI at all taxonomic ranks (R 2 = 0.60; Q 2 = 0.23) and genus levels (R 2 = 0.57; Q 2 = 0.37). The relative abundances of Akkermansia (P < 0.05; false discovery rate [FDR] < 0.05), Olsenella (P < 0.05; FDR < 0.05) and Oscillospira (P < 0.05; FDR < 0.05) were found to be significantly higher in normal BMI cases by 2.4, 3.4 and 3.1 times, respectively.
CONCLUSION: Three genera (Akkermansia, Olsenella and Oscillospira) were correlated with normal BMI during pregnancy. All three could be promising biotherapeutic targets in body weight regulation during pregnancy, subsequently reducing complications associated with higher BMI.
Salivaomics in head and neck cancer

Saravanan C, S M N Mydin RB, Mohamed Sheriff NR, Kaur G, Singh Dhaliwal S, Musa MY

Clin Chim Acta, 2024 Aug 30;565:119952.
PMID: 39216814 DOI: 10.1016/j.cca.2024.119952

Salivaomics is a promising method for the early detection and monitoring of head and neck cancer (HNC). By analyzing salivary proteomics, RNA, and DNA, it identifies biomarkers that distinguish HNC patients from healthy individuals. Saliva's non-invasive, easily collectible nature and affordability make it an advantageous screening tool. Multiomics approaches, which explore genetic mutations, gene expression patterns, protein profiles, and metabolite levels, provide a comprehensive molecular perspective that enhances clinical applicability. The approaches enhance the precision of diagnoses, enable the development and application of targeted therapies, and contribute to the overall advancement of personalized medicine. Despite its potential, larger-scale studies are essential for validating biomarkers, and assessing sensitivity, accuracy, and specificity in detecting HNC. This review highlights salivaomics' potential as a non-invasive, accessible biological sample for early disease detection in HNC and underscores the value of multiomics in advancing this research. Salivaomics offers significant insights into the underlying mechanisms of HNC, enabling the discovery of robust, non-invasive biomarkers for improved disease management.
Chemometric techniques in oil classification from oil spill fingerprinting

Ismail A, Toriman ME, Juahir H, Kassim AM, Zain SM, Ahmad WKW, et al.

Mar Pollut Bull, 2016 Oct 15;111(1-2):339-346.
PMID: 27397593 DOI: 10.1016/j.marpolbul.2016.06.089

Extended use of GC-FID and GC-MS in oil spill fingerprinting and matching is significantly important for oil classification from the oil spill sources collected from various areas of Peninsular Malaysia and Sabah (East Malaysia). Oil spill fingerprinting from GC-FID and GC-MS coupled with chemometric techniques (discriminant analysis and principal component analysis) is used as a diagnostic tool to classify the types of oil polluting the water. Clustering and discrimination of oil spill compounds in the water from the actual site of oil spill events are divided into four groups viz. diesel, Heavy Fuel Oil (HFO), Mixture Oil containing Light Fuel Oil (MOLFO) and Waste Oil (WO) according to the similarity of their intrinsic chemical properties. Principal component analysis (PCA) demonstrates that diesel, HFO, MOLFO and WO are types of oil or oil products from complex oil mixtures with a total variance of 85.34% and are identified with various anthropogenic activities related to either intentional releasing of oil or accidental discharge of oil into the environment. Our results show that the use of chemometric techniques is significant in providing independent validation for classifying the types of spilled oil in the investigation of oil spill pollution in Malaysia. This, in consequence would result in cost and time saving in identification of the oil spill sources.
Synthesis of amorphous platinum nanofibers directly on an ITO substrate and its heterogeneous catalytic hydrogenation characterization

Balouch A, Ali Umar A, Mawarnis ER, Md Saad SK, Mat Salleh M, Abd Rahman MY, et al.

ACS Appl Mater Interfaces, 2015 Apr 15;7(14):7776-85.
PMID: 25807116 DOI: 10.1021/acsami.5b01012

This paper reports a facile, solution-phase approach to synthesizing a one-dimensional amorphous face-centered-cubic (fcc) platinum (a-Pt) nanostructure (nanofibers) directly on an indium-tin oxide (ITO) substrate. The electron microscopy analysis result shows that the a-Pt nanofiber has a diameter and length of approximately 50 nm and 1 μm, respectively, and is grown in high density on the entire surface of the ITO substrate. The X-ray photoelectron spectroscopy analysis result further reveals that the a-Pt nanofibers feature metallic properties with highly reactive surface chemistry, promising novel performance in electrochemistry, catalysis, and sensors. A synergetic interplay between the formic acid reducing agent and the hexamethylenetetramine surfactant in the reduction of Pt ions is assumed as the driving force for the formation of the amorphous phase in the Pt nanostructure. The catalytic properties of a-Pt were examined in the acetone hydrogenation reaction under microwave irradiation. a-Pt shows excellent heterogeneous catalytic properties for converting acetone to isopropyl alcohol with turnover number and frequency as high as 400 and 140 min(-1), respectively. The preparation and formation mechanism of the a-Pt nanofibers will be discussed in detail in this paper.
Fulltext Two-Dimensional, Hierarchical Ag-Doped TiO2 Nanocatalysts: Effect of the Metal Oxidation State on the Photocatalytic Properties

Md Saad SK, Ali Umar A, Ali Umar MI, Tomitori M, Abd Rahman MY, Mat Salleh M, et al.

ACS Omega, 2018 Mar 31;3(3):2579-2587.
PMID: 31458546 DOI: 10.1021/acsomega.8b00109

This paper reports the synthesis of two-dimensional, hierarchical, porous, and (001)-faceted metal (Ag, Zn, and Al)-doped TiO2 nanostructures (TNSs) and the study of their photocatalytic activity. Two-dimensional metal-doped TNSs were synthesized using the hydrolysis of ammonium hexafluorotitanate in the presence of hexamethylenetetramine and metal precursors. Typical morphology of metal-doped TNSs is a hierarchical nanosheet that is composed of randomly stacked nanocubes (dimensions of up to 5 μm and 200 nm in edge length and thickness, respectively) and has dominant (001) facets exposed. Raman analysis and X-ray photoelectron spectroscopy results indicated that the Ag doping, compared to Zn and Al, much improves the crystallinity degree and at the same time dramatically lowers the valence state binding energy of the TNS and provides an additional dopant oxidation state into the system for an enhanced electron-transfer process and surface reaction. These are assumed to enhance the photocatalytic of the TNS. In a model of photocatalytic reaction, that is, rhodamine B degradation, the AgTNS demonstrates a high photocatalytic activity by converting approximately 91% of rhodamine B within only 120 min, equivalent to a rate constant of 0.018 m-1 and ToN and ToF of 94 and 1.57 min-1, respectively, or 91.1 mmol mg-1 W-1 degradation when normalized to used light source intensity, which is approximately 2 times higher than the pristine TNS and several order higher when compared to Zn- and Al-doped TNSs. Improvement of the crystallinity degree, decrease in the defect density and the photogenerated electron and hole recombination, and increase of the oxygen vacancy in the AgTNS are found to be the key factors for the enhancement of the photocatalytic properties. This work provides a straightforward strategy for the preparation of high-energy (001) faceted, two-dimensional, hierarchical, and porous Ag-doped TNSs for potential use in photocatalysis and photoelectrochemical application.
Fulltext Effects of Waste Frying Oil and Crumb Rubber on the Characteristics of a Reclaimed Asphalt Pavement Binder

Bilema M, Aman MY, Hassan NA, Al-Saffar Z, Mashaan NS, Memon ZA, et al.

Materials (Basel), 2021 Jun 23;14(13).
PMID: 34201413 DOI: 10.3390/ma14133482

The reclaimed asphalt pavement (RAP) has become a moderately common practice in most countries; Hence, rejuvenating materials with RAP have earned publicity in the asphalt manufacturers, mainly due to the increasing raw material costs. In this study, the crumb rubber (CR) and waste frying oil (WFO) utilized as waste materials to restore the properties and enhance the rutting resistance of the RAP. Several physical, rheological, chemical properties of bituminous binders were tested. The result showed that the RAP bituminous binders incorporating WFO and CR decreased softening points and the increased penetration value; these translate to an increase in penetration index. Moreover, the viscosity of the WFO/CR combination reclaimed asphalt pavement binder showed better workability and stiffness, as well as a low storage stability temperature (less than 2.2 °C) with an acceptable loss upon heating. Without chemical reaction was observed between the waste-frying oil with the rubberized binder and the reclaimed asphalt pavement binder. Additionally, the WFO/CR rheological properties combined with the reclaimed asphalt pavement binder were comparable to the control sample. The incorporation of CR with WFO as a hybrid rejuvenator enhanced the rutting resistance. Therefore, the presence of WFO/CR has a considerable influence on the RAP binder properties while preserving a better environment and reducing pollution by reusing waste materials.
Fulltext Nasopharyngeal Carcinoma (NPC) Risk Factors: A Systematic Review and Meta-Analysis of the Association with Lifestyle, Diets, Socioeconomic and Sociodemographic in Asian Region

Okekpa SI, S M N Mydin RB, Mangantig E, Azmi NSA, Zahari SNS, Kaur G, et al.

Asian Pac J Cancer Prev, 2019 Nov 01;20(11):3505-3514.
PMID: 31759378 DOI: 10.31557/APJCP.2019.20.11.3505

OBJECTIVE: Risk factors of nasopharyngeal carcinoma (NPC) have been linked with diets, life style and viral
infections. NPC is more rampant in Asian populations than non-Asian countries. Our study aims to assess the validity
of the suggestions provided by multiple case control studies demonstrating that salted fish consumption, smoking and
alcohol consumption are associated with the risk of NPC in Asia.
METHODS: Search for related literature on salted fish,
smoking and alcohol consumption were performed via Science Direct, PubMed databases and Google Scholar. Articles
included in this study were from 2009 to 2017, with specific focus on salted fish, smoking and alcohol consumption
as risk factors of NPC. This study excluded all articles published prior to 2009 and articles involving other cancers.
Data were extracted independently by two different researchers and harmonized. Meta-analysis was conducted on the
obtained data, by using R package Meta to create funnel and forest plots.
RESULTS: The meta-analysis revealed that
salted fish, smoking and alcohol consumption were significantly associated to NPC risk with random effect model score
showing OR of 1.41 at 95% confidence interval (CI) of 1.13-1.75 (P<0.01), OR of 1.89 at 95 % CI of 1.49 - 2.38, and
OR: 1.42 at 95 % CI of 1.23 - 1.65 respectively. Our results also revealed significant association of salted meat, salted
vegetables, house type, wood dust exposure associated with NPC risk with p values less than 0.05.
CONCLUSION: This
study proposes that salted fish intake, smoking and alcohol consumption might be linked to NPC risk in Asians. Further
studies are necessary to ascertain the molecular mechanisms and clarify if the associated path that could function as
therapeutic target.
Fulltext Investigating the motivating factors that influence the adoption of blended learning for teachers' professional development

Dahri NA, Yahaya N, Al-Rahmi WM, Noman HA, Alblehai F, Kamin YB, et al.

Heliyon, 2024 Aug 15;10(15):e34900.
PMID: 39145035 DOI: 10.1016/j.heliyon.2024.e34900

Blended learning (BL), a teaching method merging online and face-to-face learning, is lauded for its potential to enrich educational outcomes and tackle challenges entrenched in conventional teaching practices. In countries like Pakistan, where equitable access to quality professional development remains an obstacle, BL is a promising avenue to surmount training barriers. While BL adoption has evolved swiftly, research into its integration within teacher training remains limited. Notably, no comprehensive model exists describing the motivational factors influencing teachers' perceptions and intentions regarding the blended mode of teacher training. This study aims to identify the motivational elements that motivate schoolteachers in teacher training institutions in Pakistan to incorporate blended learning into their programs. The motivational factors identified in BL literature have been employed to craft a motivation model grounded in their causal relationship. This quantitative study examines the interplay between multiple motivational factors and their impact on BL adoption within teacher training and the BL environment. Surveying 350 schoolteachers (participants) from teacher training institutions, we employed Structural Equation Modeling (SEM) techniques with Smart PLS 4.0 for data analysis. Results reveal that extrinsic and intrinsic motivational factors significantly influence teachers' motivation to adopt BL for training. Notably, "overall training quality" and "educational environment" were non-influential. Overall, the findings underscore that considering a blend of extrinsic and intrinsic factors can wield a 65 % influence on BL adoption. The study's results provide practical guidance for educational leaders, curriculum designers, and faculty members aiming to cultivate a unified blended learning environment for teacher professional development. These insights also underscore the importance of incorporating essential motivational factors into forthcoming blended learning training programs.
Fulltext Celastrol: A Potential Natural Lead Molecule for New Drug Design, Development and Therapy for Memory Impairment

Amir Yusri MA, Sekar M, Wong LS, Gan SH, Ravi S, Subramaniyan V, et al.

Drug Des Devel Ther, 2023;17:1079-1096.
PMID: 37064431 DOI: 10.2147/DDDT.S389977

Celastrol is a naturally occurring chemical isolated from Tripterygium wilfordii Hook. f., root extracts widely known for their neuroprotective properties. In this review, we focus on the efficacy of celastrol in mitigating memory impairment (MI) in both in vivo and in vitro models. Scopus, PubMed and Web of Science databases were utilised to locate pertinent literatures that explore the effects of celastrol in the brain, including its pharmacokinetics, bioavailability, behavioral effects and some of the putative mechanisms of action on memory in many MI models. To date, preclinical studies strongly suggest that celastrol is highly effective in enhancing the cognitive performance of MI animal models, particularly in the memory domain, including spatial, recognition, retention and reference memories, via reduction in oxidative stress and attenuation of neuro-inflammation, among others. This review also emphasised the challenges and potential associated enhancement of medication delivery for MI treatment. Additionally, the potential structural alterations and derivatives of celastrol in enhancing its physicochemical and drug-likeness qualities are examined. The current review demonstrated that celastrol can improve cognitive performance and mitigate MI in several preclinical investigations, highlighting its potential as a natural lead molecule for the design and development of a novel neuroprotective medication.
Fulltext Genistein: A Potential Natural Lead Molecule for New Drug Design and Development for Treating Memory Impairment

Fuloria S, Yusri MAA, Sekar M, Gan SH, Rani NNIM, Lum PT, et al.

Molecules, 2022 Jan 01;27(1).
PMID: 35011497 DOI: 10.3390/molecules27010265

Genistein is a naturally occurring polyphenolic molecule in the isoflavones group which is well known for its neuroprotection. In this review, we summarize the efficacy of genistein in attenuating the effects of memory impairment (MI) in animals. Scopus, PubMed, and Web of Science databases were used to find the relevant articles and discuss the effects of genistein in the brain, including its pharmacokinetics, bioavailability, behavioral effects, and some of the potential mechanisms of action on memory in several animal models. The results of the preclinical studies highly suggested that genistein is highly effective in enhancing the cognitive performance of the MI animal models, specifically in the memory domain, including spatial, recognition, retention, and reference memories, through its ability to reduce oxidative stress and attenuate neuroinflammation. This review also highlighted challenges and opportunities to improve the drug delivery of genistein for treating MI. Along with that, the possible structural modifications and derivatives of genistein to improve its physicochemical and drug-likeness properties are also discussed. The outcomes of the review proved that genistein can enhance the cognitive performance and ameliorate MI in different preclinical studies, thus indicating its potential as a natural lead for the design and development of a novel neuroprotective drug.
Photoelectrical Dynamics Uplift in Perovskite Solar Cells by Atoms Thick 2D TiS2 Layer Passivation of TiO2 Nanograss Electron Transport Layer

Alias N, Ali Umar A, Malek NAA, Liu K, Li X, Abdullah NA, et al.

ACS Appl Mater Interfaces, 2021 Jan 20;13(2):3051-3061.
PMID: 33410652 DOI: 10.1021/acsami.0c20137

A deficiency in the photoelectrical dynamics at the interface due to the surface traps of the TiO2 electron transport layer (ETL) has been the critical factor for the inferiority of the power conversion efficiency (PCE) in the perovskite solar cells. Despite its excellent energy level alignment with most perovskite materials, its large density of surface defect as a result of sub lattice vacancies has been the critical hurdle for an efficient photovoltaic process in the device. Here, we report that atoms thick 2D TiS2 layer grown on the surface of a (001) faceted and single-crystalline TiO2 nanograss (NG) ETL have effectively passivated the defects, boosting the charge extractability, carrier mobility, external quantum efficiency, and the device stability. These properties allow the perovskite solar cells (PSCs) to produce a PCE as high as 18.73% with short-circuit current density (Jsc), open-circuit voltage (Voc), and fill-factor (FF) values as high as 22.04 mA/cm2, 1.13 V, and 0.752, respectively, a 3.3% improvement from the pristine TiO2-NG-based PSCs. The present approach should find an extensive application for controlling the photoelectrical dynamic deficiency in perovskite solar cells.
Fulltext Implementing circularity measurements in industry 4.0-based manufacturing metrology using MQTT protocol and Open CV: A case study

Saif Y, Yusof Y, Rus AZM, Ghaleb AM, Mejjaouli S, Al-Alimi S, et al.

PLoS One, 2023;18(10):e0292814.
PMID: 37831665 DOI: 10.1371/journal.pone.0292814

In the context of Industry 4.0, manufacturing metrology is crucial for inspecting and measuring machines. The Internet of Things (IoT) technology enables seamless communication between advanced industrial devices through local and cloud computing servers. This study investigates the use of the MQTT protocol to enhance the performance of circularity measurement data transmission between cloud servers and round-hole data sources through Open CV. Accurate inspection of circular characteristics, particularly roundness errors, is vital for lubricant distribution, assemblies, and rotational force innovation. Circularity measurement techniques employ algorithms like the minimal zone circle tolerance algorithm. Vision inspection systems, utilizing image processing techniques, can promptly and accurately detect quality concerns by analyzing the model's surface through circular dimension analysis. This involves sending the model's image to a computer, which employs techniques such as Hough Transform, Edge Detection, and Contour Analysis to identify circular features and extract relevant parameters. This method is utilized in the camera industry and component assembly. To assess the performance, a comparative experiment was conducted between the non-contact-based 3SMVI system and the contact-based CMM system widely used in various industries for roundness evaluation. The CMM technique is known for its high precision but is time-consuming. Experimental results indicated a variation of 5 to 9.6 micrometers between the two methods. It is suggested that using a high-resolution camera and appropriate lighting conditions can further enhance result precision.
Fulltext Correlation between the maximum standard uptake value and mean Hounsfield unit on single-photon emission computed tomography-computed tomography to discriminate benign and metastatic lesions among patients with breast cancer

Saminathan ST, Ahmed WAW, Nawi NM, Tagiling N, Aziz I, Udin Y, et al.

Asian Spine J, 2024 Jun;18(3):398-406.
PMID: 38917860 DOI: 10.31616/asj.2022.0451

STUDY DESIGN: Retrospective study.
PURPOSE: To compare and correlate technetium-99m methylene diphosphonate uptake between benign and metastatic bone lesions using semiquantitative analysis of maximum standard uptake value (SUVmax) and mean Hounsfield unit (HU) in single-photon emission computed tomography-computed tomography (SPECT-CT).
OVERVIEW OF LITERATURE: Qualitative interpretation of metastatic bone lesions in breast cancer on bone scintigraphy is often complicated by coexisting benign lesions.
METHODS: In total, 185 lesions were identified on bone and SPECT-CT scans from 32 patients. Lesions were classified as metastatic (109 sclerotic lesions) and benign (76 lesions) morphologically on low-dose CT. Semiquantitative analysis using SUVmax and mean HU was performed on the lesions and compared. To discriminate benign and metastatic lesions, the correlation between SUVmax and mean HU was determined using the intraclass correlation coefficients.
RESULTS: The SUVmax was higher in metastatic lesions (20.66±14.36) but lower in benign lesions (10.18±12.79) (p<0.001). The mean HU was lower in metastatic lesions (166.62±202.02) but higher in benign lesions (517.65±192.8) (p<0.001). A weak negative correlation was found between the SUVmax and the mean HU for benign lesions, and a weak positive correlation was noted between the SUVmax and the mean HU on malignant lesions with no statistical significance (p=0.394 and 0.312, respectively). The cutoff values obtained were 10.8 for SUVmax (82.6% sensitivity and 84.2% specificity) and 240.86 for the mean HU (98.7% sensitivity and 88.1% specificity) in differentiating benign from malignant bone lesions.
CONCLUSIONS: Semiquantitative assessment using SUVmax and HU can complement qualitative analysis. Metastatic lesions had higher SUVmax but lower mean HU than benign lesions, whereas benign lesions demonstrated higher mean HU but lower SUVmax. A weak correlation was found between the SUVmax and the mean HU on malignant and benign lesions. Cutoff values of 10.8 for the SUVmax and 240.86 for the mean HU may differentiate bone metastases from benign lesions.
Randomized, crossover trial: comparing the effects of standardized egg-white meal and Vital® on global gastric emptying parameters and intragastric meal distribution in healthy Asian participants

Tagiling N, Ibrahim IL, Lee YY, Udin MY, Mohamad Kamarulzaman MD, Phoa PKA, et al.

J Gastroenterol Hepatol, 2024 May 05.
PMID: 38705971 DOI: 10.1111/jgh.16585

BACKGROUND AND AIM: Measurements of gastric emptying and accommodation for alternative test-meal protocol during gastric emptying scintigraphy (GES), such as high-calorie nutrient drinks, are not fully established. We aimed to compare the effects of standardized egg-white meal (EWM) versus high-calorie nutrient drink (Vital®; Abbott Laboratories) on global GES parameters and intragastric meal distribution at immediate scan (IMD0h).
METHODS: Of 84 screened participants, 60 asymptomatic healthy Asian population (38 females; 24.0 ± 1.5 years; 23.8 ± 2.6 kg/m2) were recruited in this 2 × 2 (AB/BA) crossover trial. Participants were randomized to a 4-h GES with 99mTc-radiolabeled EWM (~255.8 kcal), followed by a 200 mL Vital® (300 kcal), or vice versa, separated by a 2-week washout period. Global meal retention (GMR), power-exponential model emptying parameters (half-emptying [T1/2], lag phases [Tlag2%, Tlag5%, Tlag10%]), and IMD0h were determined and compared.
RESULTS: GMRs for both test meals were within the international standard references for solid GES. Compared to EWM, Vital® exhibited significantly lower GMRs (faster emptying) from 0.5 to 3 h (all P
Fulltext Calibration Model of a Low-Cost Air Quality Sensor Using an Adaptive Neuro-Fuzzy Inference System

Alhasa KM, Mohd Nadzir MS, Olalekan P, Latif MT, Yusup Y, Iqbal Faruque MR, et al.

Sensors (Basel), 2018 Dec 11;18(12).
PMID: 30544953 DOI: 10.3390/s18124380

Conventional air quality monitoring systems, such as gas analysers, are commonly used in many developed and developing countries to monitor air quality. However, these techniques have high costs associated with both installation and maintenance. One possible solution to complement these techniques is the application of low-cost air quality sensors (LAQSs), which have the potential to give higher spatial and temporal data of gas pollutants with high precision and accuracy. In this paper, we present DiracSense, a custom-made LAQS that monitors the gas pollutants ozone (O₃), nitrogen dioxide (NO₂), and carbon monoxide (CO). The aim of this study is to investigate its performance based on laboratory calibration and field experiments. Several model calibrations were developed to improve the accuracy and performance of the LAQS. Laboratory calibrations were carried out to determine the zero offset and sensitivities of each sensor. The results showed that the sensor performed with a highly linear correlation with the reference instrument with a response-time range from 0.5 to 1.7 min. The performance of several calibration models including a calibrated simple equation and supervised learning algorithms (adaptive neuro-fuzzy inference system or ANFIS and the multilayer feed-forward perceptron or MLP) were compared. The field calibration focused on O₃ measurements due to the lack of a reference instrument for CO and NO₂. Combinations of inputs were evaluated during the development of the supervised learning algorithm. The validation results demonstrated that the ANFIS model with four inputs (WE OX, AE OX, T, and NO₂) had the lowest error in terms of statistical performance and the highest correlation coefficients with respect to the reference instrument (0.8 < r < 0.95). These results suggest that the ANFIS model is promising as a calibration tool since it has the capability to improve the accuracy and performance of the low-cost electrochemical sensor.

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