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Abundance, Fishing Season and Management Strategy for Blue Swimming Crab (Portunus pelagicus) in Pangkajene Kepulauan, South Sulawesi, Indonesia

Wiyono ES, Ihsan

Trop Life Sci Res, 2018 Mar;29(1):1-15.
PMID: 29644012 DOI: 10.21315/tlsr2018.29.1.1

In order to manage blue swimming crabs in Pangkajene Kepulauan, management measures are required. Since the environment which affects the abundance of the blue swimming crab varies seasonally, it is necessary to take into account the seasonal nature with the aim of developing a management strategy. The objectives of this study are to define the abundance of and fishing season of blue swimming crabs in the Pangkajene Kepulauan waters, South Sulawesi, Indonesia. The fishing season was analysed using seasonal index analysis, while fish abundance was analysed by means of Equilibrium-Schaefer. The result of this study demonstrated that fishermen allocate their fishing gear all year, although the fish catch is seasonal. Based on analysis of the result, the fishing season for the blue swimming crabs is short. The peak fishing season starts in May and finishes in June. However, in order to enable their families to earn a living, fishermen operated their fishing gear throughout the year. As a result, both catch landing and effort were close to maximum sustainable yield (MSY). In order to reduce fishing pressure, it is necessary to reduce fishing gear and have a seasonal arrangement regarding fishing gear allocation.
A Comprehensive Review of the Cosmeceutical Benefits of Vanda Species (Orchidaceae)

Hadi H, Razali SN, Awadh AI

Nat Prod Commun, 2015 Aug;10(8):1483-8.
PMID: 26434147

Orchidaceae is the largest family of flowering plants with over 35,000 species and 850 genera. About 3300 species of orchids are found in Malaysia and the diversity is highest in the Main, Keledang, Bintang and Tahan Ranges. Apart from being prized for their beauty, orchids have long been used by humans for medicinal purposes. Today the uses of orchids have been expanded to the food and cosmetics industries. Many cosmeceutical companies use orchid extracts as an active ingredient in their products. Previous studies provide riveting insights into the potential uses of orchid extracts as an active agent in cosmetics. This paper describes the cosmeceutical potential of orchids as an anti-aging, and skin moisturizing agent. Orchid extracts from Vanda coerulea and V. teres delay aging caused by reactive oxygen species (ROS) following LV irradiation through their antioxidant and anti-inflammatory activity. These extracts also show anti-aging properties by stimulating cytochrome c oxidase (complex IV), which is part of the electron transport chain in mitochondria. Stimulation of cytochrome c oxidase improves the respiratory function of mitochondria in keratinocytes. The presence of mucilage in orchids enables them to maintain skin hydration. Mucilage functions as a moisturizer and emollient due to its high water binding capacity. Additionally, orchid extracts provide skin hydration by stimulating aquaporin 3 (AQP3) and LEKTI protein expression. The presence of AQP3 leads to a five-fold increase in water permeability, which subsequently increases stratum corneum hydration. Increased LEKTI protein expression mediated by orchid extracts reduces the degradation of desmoglein-1 and enhances the structural function of desmosomes, which play important roles in preventing water evaporation.
Fulltext Comparative cost analysis of virtual consultation for outpatient service in Malaysian public health clinics

Abdul Razak I, Sukeri S, Hamid NAA

J Family Med Prim Care, 2026 Jul;15(7):2510-2519.
PMID: 42964866 DOI: 10.4103/jfmpc.jfmpc_212_26

CONTEXT: Malaysia has rapidly expanded Virtual Consultation Services (VCS) in public primary care to improve access and reduce healthcare burden. However, local evidence on patient-incurred cost savings from VCS remains limited.
OBJECTIVES: This study estimated the mean cost saving per patient from virtual consultations compared with physical consultations and examined differences in patient-incurred costs between the two modalities in Malaysian public primary care.
METHODS: A cross-sectional study was conducted from July to October 2025 in 91 government health clinics across East and West Malaysia. Malaysian adults aged ≥18 years who had attended at least one physical and one virtual outpatient follow-up consultation were included. Cost data were collected from the patient's perspective using a structured online proforma. Direct and indirect costs were identified, measured, and valued. Paired t-tests were used to compare mean costs, with Wilcoxon signed-rank tests performed as sensitivity analyses.
RESULTS: A total of 420 participants were included (mean age 37.23 years [SD = 11.04]; 78.3% female). The mean total cost of a physical consultation was RM47.97 (SD = RM60.69), compared with RM0.04 (SD = RM0.69) for a virtual consultation. The mean cost saving per patient was RM47.93 (SD = RM60.64), with a significant mean difference (95% CI: RM42.12-RM53.75; P < 0.001). Travel costs and productivity loss were the main contributors to cost savings.
CONCLUSION: Virtual consultations resulted in substantial patient-level cost savings compared with physical consultations, supporting continued scale-up of VCS in Malaysian public primary care.
Fulltext Mechanical behaviour and microstructure Aluminium Foam Tube Produce (AFTP) using infiltration method with vacuum-gas

Ismail Lias, Muhammad Hussain Ismail, Iskandar Dzulkernain Md Raffee, Mohd Aman Ihsan Mamat

Pertanika Journal of Science & Technology, 2017;25(103):223-232.
MyJurnal

Aluminium foam tube is a metal that consists of porous medium with special characteristics such as good energy absorption, good heat transfer and high thermal conductivity. These make it suitable to be used in a wide range of applications such as in heat exchangers. The aim of this project is to identify and analyse mechanical behaviour and microstructure aluminium foam tube produced and fabricated with infiltration method with vacuum-gas. The density of aluminium foam tube was also determined and an average aluminium foam tube with porosity 50% - 80% with the average NaCl particle size 2mm, 3mm and 4mm was produced. Foams with porosity 60%-75% NaCl has higher energy absorption. These was based on foam structure, density and maximum compressive load test result.
Fulltext Developing multi-tier network design for effective energy consumption of cluster head selection in WSN

Wan Isni Sofiah Wan Din, Saadiah Yahya, Mohd Nasir Taib, Ahmad Ihsan Mohd Yassin, Razulaimi Razali

Scientific Research Journal, 2016;13(1):1-11.
MyJurnal

Clustering in Wireless Sensor Network (WSN) is one of the methods to minimize the energy usage of
sensor network. The design of sensor network itself can prolong the lifetime of network. Cluster head in
each cluster is an important part in clustering to ensure the lifetime of each sensor node can be preserved
as it acts as an intermediary node between the other sensors. Sensor nodes have the limitation of its
battery where the battery is impossible to be replaced once it has been deployed. Thus, this paper
presents an improvement of clustering algorithm for two-tier network as we named it as Multi-Tier
Algorithm (MAP). For the cluster head selection, fuzzy logic approach has been used which it can
minimize the energy usage of sensor nodes hence maximize the network lifetime. MAP clustering
approach used in this paper covers the average of 100Mx100M network and involves three parameters
that worked together in order to select the cluster head which are residual energy, communication cost
and centrality. It is concluded that, MAP dominant the lifetime of WSN compared to LEACH and SEP
protocols. For the future work, the stability of this algorithm can be verified in detailed via different data
and energy.
Fulltext Suppression of Cisplatin-Induced Vomiting byCannabis sativain Pigeons: Neurochemical Evidences

Ullah I, Subhan F, Alam J, Shahid M, Ayaz M

Front Pharmacol, 2018;9:231.
PMID: 29615907 DOI: 10.3389/fphar.2018.00231

Cannabis sativa
(CS, familyCannabinaceae) has been reported for its anti-emetic activity against cancer chemotherapy-induced emesis in animal models and in clinics. The current study was designed to investigateCSfor potential effectiveness to attenuate cisplatin-induced vomiting in healthy pigeons and to study the impact on neurotransmitters involved centrally and peripherally in the act of vomiting. High-performance liquid chromatography system coupled with electrochemical detector was used for the quantification of neurotransmitters 5-hydroxytryptamine (5HT), dopamine (DA) and their metabolites; Di-hydroxy Phenyl Acetic acid (Dopac), Homovanillic acid (HVA), and 5-hydroxy indole acetic acid (5HIAA) centrally in specific brain areas (area postrema and brain stem) while, peripherally in small intestine. Cisplatin (7 mg/kg i.v.) induce emesis without lethality across the 24 h observation period.CShexane fraction (CS-HexFr; 10 mg/kg) attenuated cisplatin-induced emesis ∼ 65.85% (P< 0.05); the reference anti-emetic drug, metoclopramide (MCP; 30 mg/kg), produced ∼43.90% reduction (P< 0.05). At acute time point (3rdh), CS-HexFr decreased (P< 0.001) the concentration of 5HT and 5HIAA in the area postrema, brain stem and intestine, while at 18thh (delayed time point) CS-HexFr attenuated (P< 0.001) the upsurge of 5HT caused by cisplatin in the brain stem and intestine and dopamine in the area postrema.CS-HexFr treatment alone did not alter the basal neurotransmitters and their metabolites in the brain areas and intestine except 5HIAA and HVA, which were decreased significantly. In conclusion the anti-emetic effect ofCS-HexFr is mediated by anti-serotonergic and anti-dopaminergic components in a blended manner at the two different time points, i.e., 3rdand 18thh in pigeons.
The use of sunscreen products among final year medicine and pharmacy students: A cross-sectional study of knowledge, attitude, practice, and perception

Awadh AI, Jamshed S, Elkalmi RM, Hadi H

J Res Pharm Pract, 2016 Jul-Sep;5(3):193-9.
PMID: 27512711 DOI: 10.4103/2279-042X.185731

OBJECTIVE: To evaluate the knowledge, attitude, perception, and practice of medical and pharmacy students toward the usage of sunscreen as protection for the skin against ultraviolet (UV) radiation.
METHODS: This cross-sectional study was conducted among final year medical and pharmacy undergraduates at the International Islamic University Malaysia. Validated questionnaires were distributed to 134 medical students and 100 pharmacy students. Descriptive and inferential statistics were used where appropriate.
FINDINGS: One hundred and sixty-one out of 234 participants completed the questionnaires. The participants comprised 101 medical students (75.4%) and sixty pharmacy students (60.0%). The majority of the respondents were females (102; 63.4%), and 59 (36.6%) were males. The median of the knowledge scores of the final year medical students was significantly lower than that of the final year pharmacy students (P < 0.001). The female students showed significantly higher knowledge scores than the male students (P = 0.027). This study reported that 24 (39.3%) pharmacy students were influenced by the media to use sunscreen, whereas 35 (34.7%) medical students were influenced the most by friends to use sunscreen. The final year pharmacy students had a better perception compared to the medical students, with the total perception score of the final year pharmacy students being significantly higher than that of the final year medical students (P = 0.020). Most of the participants were also aware of the harmful effects of UV radiation and had a positive reaction toward the usage of sunscreen to prevent those harmful effects.
CONCLUSION: The knowledge and perception of final year pharmacy students were significantly higher than the knowledge and perception of final year medical students with regard to the usage of sunscreen.
KEYWORDS: Attitude; knowledge; perception; practice; sunscreen
Fulltext Improving the performance of opportunistic routing using min-max range and optimum energy level for relay node selection in wireless sensor networks

Yee PL, Mehmood S, Almogren A, Ali I, Anisi MH

PeerJ Comput Sci, 2020;6:e326.
PMID: 33816976 DOI: 10.7717/peerj-cs.326

Opportunistic routing is an emerging routing technology that was proposed to overcome the drawback of unreliable transmission, especially in Wireless Sensor Networks (WSNs). Over the years, many forwarder methods were proposed to improve the performance in opportunistic routing. However, based on existing works, the findings have shown that there is still room for improvement in this domain, especially in the aspects of latency, network lifetime, and packet delivery ratio. In this work, a new relay node selection method was proposed. The proposed method used the minimum or maximum range and optimum energy level to select the best relay node to forward packets to improve the performance in opportunistic routing. OMNeT++ and MiXiM framework were used to simulate and evaluate the proposed method. The simulation settings were adopted based on the benchmark scheme. The evaluation results showed that our proposed method outperforms in the aspect of latency, network lifetime, and packet delivery ratio as compared to the benchmark scheme.
Ion exchange membrane electrodialysis for water and wastewater processing: application of ladder-type membrane spacers to impact solution concentration and flow dynamics

Al-Amshawee SKA, Yunus MYBM, Dakhil IH

Environ Sci Pollut Res Int, 2023 Jun 13.
PMID: 37308631 DOI: 10.1007/s11356-023-27940-z

Concentration polarization, which creates a thin boundary layer along the membranes in electrochemical reactors and electrodialysis-related processes, is one of the main issues. Membrane spacers provide swirling motion in the stream and distribute fluid toward the membrane, which effectively breaks the polarization layer and maximizes flux steadily. Membrane spacers and the spacer-bulk attack angle are reviewed systematically in the current study. The study then in-depth reviews a ladder-type configuration composed of longitudinal (0° attack angle) and transverse (90° attack angle) filaments, and its effects on solution flow direction and hydrodynamics. The review discovered that, at the tradeoff of high-pressure losses, a laddered spacer can provide mass transfer and mixing activity along the channel while preserving comparable patterns of concentration near the membrane wall. Pressure losses are driven by a change in the direction of velocity vectors. Dead spots in the spacer design that are created by the large contribution of the spacer manifolds can be reduced using the high-pressure drop. Laddered spacers also permit long, tortuous flow paths, which help to create turbulent flow and prevent concentration polarization. The absence of spacers produces limited mixing and broad polarization effects. A major portion of streamlines changes direction at ladder spacer strands positioned transverse to the main flow by moving in a zigzag manner up and down the filaments of the spacer. Flow at 90° is perpendicular to the transverse wires in [Formula: see text]-coordinate, no change in [Formula: see text]-coordinate.
Clinical Outcomes of Topical Bevacizumab for the Treatment of Corneal Neovascularization

Jamaludin MI, Wan Abdul Halim WH, Cheng TC

Cureus, 2024 May;16(5):e59548.
PMID: 38707752 DOI: 10.7759/cureus.59548

Background and objective In corneal neovascularization, the peri-corneal vascular structure grows into a normally avascular cornea. This is due to an imbalance between the angiogenic and anti-angiogenic factors that sustain corneal transparency. There are various etiologies of this condition, and they can be divided into infective or non-infective causes, such as inflammation, trauma, or surgical causes. Corneal neovascularization has been shown to improve with the current treatments using steroids and anti-vascular endothelial growth factors. This study aimed to evaluate the effectiveness of topical bevacizumab as an anti-angiogenic agent in patients with corneal neovascularization. Methods This retrospective study included patients who suffered corneal neovascularization of various etiologies and completed six months of topical bevacizumab therapy between 2020 and 2022 at the Universiti Kebangsaan Malaysia Medical Centre. Results A total of 16 patients received treatment with topical bevacizumab over the three-year study period. Based on specified inclusion and exclusion criteria, 12 patients were eligible for inclusion in this study. Eight patients (66%) showed improvement in terms of either 'clock hours' of improvement, morphology, or regression of corneal neovascularization. All infective causes of corneal neovascularization showed improvement on completion of bevacizumab compared to other causes. Conclusion Topical bevacizumab can be one of the treatment choices for corneal neovascularization. As the outcome varies depending on the severity and chronicity of the condition, the attending ophthalmologist should treat each case differently. Although topical bevacizumab is more effective in mild and moderate cases, the indications for its use in chronic cases remain debatable as the results are unfavorable in such cases.
Fulltext Nonlinear multi independent variables in quantifying river bank erosion using Neural Network AutoRegressive eXogenous (NNARX) model

Saadon A, Abdullah J, Mohd Yassin I, Muhammad NS, Ariffin J

Heliyon, 2024 Feb 29;10(4):e26252.
PMID: 38404813 DOI: 10.1016/j.heliyon.2024.e26252

This study proposed a novel application of Neural Network AutoRegressive eXogenous (NNARX) model in predicting nonlinear behaviour of riverbank erosion rates which is difficult to be achieved with good accuracy using conventional approaches. This model can estimate complex river bank erosion rates with flow variations. The NNARX model analysed to a set of primary data, 60% (203 data for training) and 40% (135 data for testing), which were collected from Sg. Bernam, Malaysia. A set of nondimensional parameters, known as functional relationship, used as an input to the NNARX model has been established using the method of repeating variables. The One-Step-Ahead time series prediction plots are used to assess the accuracy of all developed models. Model no. 6 (5 independent variables with 10 hidden layers) gives good predictive performance, supported by the graphical analysis with discrepancy ratio of 94% and 90% for training and testing datasets. This finding is consistent with model accuracy result, where Model no. 6 achieved R2 of 0.932 and 0.788 for training and testing datasets, respectively. Result shows that bank erosion is maximized when the near-bank velocity between 0.2 and 0.5 m/s, and the riverbank erosion is between 1.5 and 1.8 m/year. On the other hand, higher velocities ranging from 0.8 to 1.3 m/s induces erosion at a rate between 0.1 and 0.4 m/year. Sensitivity analysis shows that the highest accuracy of 91% is given by the ratio of shear velocity to near-bank velocity followed by boundary shear stress to near-bank velocity ratio (88.5%) and critical shear stress to near-bank velocity ratio (88.2%). It is concluded that the developed model has accurately predicted non-linear behaviour of riverbank erosion rates with flow variations. The study's findings provide valuable insights in advanced simulations and predictions of channel migration, encompassing both lateral and vertical movements, the repercussions on the adjacent river corridor, assessing the extent of land degradation and in formulating plans for effective riverbank protection and management measures.
Fulltext SURF based 3D object recognition for robot hand grasping

Nurul Hanani Remeli, Ruhizan Liza Ahmad Shauri, Faieza Hanum Yahaya, Norshariza Mohd Salleh, Khairunnisa Nasir, Ahmad Ihsan Mohd Yassin

Pertanika Journal of Science & Technology, 2017;25(103):287-296.
MyJurnal

This paper proposes a 3D object recognition method based on 3D SURF and the derivation of the robot space transformations. In a previous work, a three fingered robot hand had been developed for grasping task. The reference position of the robot hand was programmed based on predetermined values for grasping two different shapes of object. The work showed successful grasping but it could not generate the reference position on its own since no external sensor was used, hence it is not fully automated. Later, a 2D Speed-Up Robust Features (SURF) and 3D point cloud algorithm were applied to calculate the object’s 3D position where the result showed that the method was capable of recognising but unable to calculate the 3D position. Thus, the present study developed 3D SURF by combining recognised images based on 2D SURF and triangulation method. The identified object grasping points then are converted to robot space using the robot’s transformation equation which is derived based on dimensions between robot and camera in the workplace. The result supported the capability of the SURF algorithm for recognising the target without fail for nine random images but produced errors in the 3D position. Meanwhile, the transformation has been successful where the calculated object positions are inclined towards the directions of actual measured positions accordingly related to robot coordinates. However, maximum error of 3.90 cm was observed due to the inaccuracy of SURF detection and human error during manual measurement which can to be solved by improving the SURF algorithm in future.
Fulltext Combined effect of temperature and light on the egg hatchability in pomaceae canaliculata (gastropoda: ampuliriidae) from Malaysia

Hasnun Nita Ismail, Mohd Fadli Mazlan, Faris Aizat Ahmad Fajri, Syed Amir Irfan Syed Ihsan, Nadia Nisha Musa

Journal of Academia Universiti Teknologi MARA Negeri Sembilan, 2019;7(2):97-103.
MyJurnal

The Golden Apple Snail (GAS), Pomacea canaliculata is an invasive species that has become a serious pest organism in rice fields in Southeast Asia since 1980s. This study was conducted to assess the hatchability of eggs under a combination effect of temperature and light. The clusters of eggs were exposed to different temperature (28oC, 30oC, 32oC, 34oC and 36oC) and under the presence and the absence of light. The finding showed that the cluster of egg hatched faster with an increase of temperature (2-way ANOVA; P < 0.05). However, the egg hatchability was not impacted by the presence or the absence of light. The combined effect between temperature and light on egg hatchability was also insignificant (2-way ANOVA; P > 0.05). Our findings indicate that temperature alone produces the main impact on the egg hatchability. Therefore, this knowledge provides an initial understanding to predict the population dynamic and geographical distribution of Pomacea from Malaysia particularly in the effort to hamper their ecological invasion.
Fulltext Comparison of the catching results of mini one-boat and two-boat purse seine in Bali strait, Muncar, east java province

Ihsan, Yudi Nurul, Khoirunisa, Nita Ulfah, Riyantini, Indah, Elfithri, Rahman, Pribadi, Tri Dewi K., Siti Nor Aisyah Md Bati

Malaysian Journal of Applied Sciences, 2020;5(1):8-14.
MyJurnal

Mini purse seine has a major contribution in increasing production of small pelagic catches in Pelabuhan Perikanan Pantai (PPP) Muncar. This research aimed to investigate the effectiveness and efficiency of mini one-boat and two-boat purse seine in Bali Strait, Indonesia. This research was conducted in Mei 2018 in Muncar, East Java, Indonesia. In this study, survey was used to get the data by distributed the questioners to the fisherman. The primary data are total catch composition, fork length, individual weight of total catch and operation time of both fishing gears. Data were analysed by main catch and bycatch proportion, legal size proportion and catch rate. The results showed that the mini two-boat purse seine had a greater catch volume compared to the mini one-boat purse seine. The bycatch composition dominates in both fishing gear. The proportion of legal-size catching is 67% of the total. The fork length is not significantly different and for the total catches is significantly different. The catching rate of the mini purse seine one boat catch rate is lower at 4,048.67 kg/hour, compared to the mini two-boat purse seine which is 9,189.18 kg/hour.
Fulltext Untargeted muscle tissue metabolites profiling in young, adult, and old rats supplemented with tocotrienol-rich fraction

Saud Gany SL, Tan JK, Chin KY, Hakimi NH, Ab Rani N, Ihsan N, et al.

Front Mol Biosci, 2022;9:1008908.
PMID: 36310588 DOI: 10.3389/fmolb.2022.1008908

The greatest significant influence on human life span and health is inevitable ageing. One of the distinguishing characteristics of ageing is the gradual decrease of muscle mass and physical function. There has been growing evidence that tocotrienol can guard against age-associated chronic diseases and metabolic disorders. This study aimed to elucidate the effects of tocotrienol-rich fraction (TRF) on muscle metabolomes and metabolic pathways in ageing Sprague Dawley (SD) rats. Three months, 9 months, and 21 months old male SD rats were divided into control and treated groups with 10 rats per group. Rats in control and treated groups were given 60 mg/kg body weight/day of palm olein and 60 mg/kg body weight/day of TRF, respectively, via oral gavage for 3 months. Muscle performance was assessed at 0 and 3 months of treatment by measuring muscle strength and function. Our results showed that TRF treatment caused a significant increase in the swimming time of the young rats. Comparison in the control groups showed that metabolites involved in lipid metabolisms such as L-palmitoyl carnitine and decanoyl carnitine were increased in ageing. In contrast, several metabolites, such as 3-phosphoglyceric acid, aspartic acid and aspartyl phenylalanine were decreased. These findings indicated that muscle metabolomes involved in lipid metabolism were upregulated in aged rats. In contrast, the metabolites involved in energy and amino acid metabolism were significantly downregulated. Comparison in the TRF-supplemented groups showed an upregulation of metabolites involved in energy and amino acid metabolism. Metabolites such as N6-methyl adenosine, spermine, phenylalanine, tryptophan, aspartic acid, histidine, and N-acetyl neuraminic acid were up-regulated, indicating promotion of amino acid synthesis and muscle regeneration. Energy metabolism was also improved in adult and old rats with TRF supplementation as indicated by the upregulation of nicotinamide adenine dinucleotide and glycerol 3-phosphate compared to the control group. In conclusion, the mechanism underlying the changes in skeletal muscle mass and functions in ageing was related to carbohydrate, lipid and amino acid metabolism. Tocotrienol supplementation showed beneficial effects in alleviating energy and amino acid synthesis that may promote the regeneration and renewal of skeletal muscle in ageing rats.
Multi-air pollution risk assessment in Southeast Asia region using integrated remote sensing and socio-economic data products

Sakti AD, Anggraini TS, Ihsan KTN, Misra P, Trang NTQ, Pradhan B, et al.

Sci Total Environ, 2023 Jan 01;854:158825.
PMID: 36116660 DOI: 10.1016/j.scitotenv.2022.158825

Air pollution has massive impacts on human life and poor air quality results in three million deaths annually. Air pollution can result from natural causes, including volcanic eruptions and extreme droughts, or human activities, including motor vehicle emissions, industry, and the burning of farmland and forests. Emission sources emit multiple pollutant types with diverse characteristics and impacts. However, there has been little research on the risk of multiple air pollutants; thus, it is difficult to identify multi-pollutant mitigation processes, particularly in Southeast Asia, where air pollution moves dynamically across national borders. In this study, the main objective was to develop a multi-air pollution risk index product for CO, NO2, and SO2 based on Sentinel-5P remote sensing data from 2019 to 2020. The risk index was developed by integrating hazard, vulnerability, and exposure analyses. Hazard analysis considers air pollution data from remote sensing, vulnerability analysis considers the air pollution sources, and exposure analysis considers the population density. The novelty of this study lies in its development of a multi-risk model that considers the weights obtained from the relationship between the hazard and vulnerability parameters. The highest air pollution risk index values were observed in urban areas, with a high exposure index that originates from pollution caused by human activity. Multi-risk analysis of the three air pollutants revealed that Singapore, Vietnam, and the Philippines had the largest percentages of high-risk areas, while Indonesia had the largest total high-risk area (4361 km2). Using the findings of this study, the patterns and characteristics of the risk distribution of multiple air pollutants in Southeast Asia can be identified, which can be used to mitigate multi-pollutant sources, particularly with respect to supporting the clean air targets in the Sustainable Development Goals.
A review: Exploring the metabolic and structural characterisation of beta pleated amyloid fibril in human tissue using Raman spectrometry and SAXS

Mohd Nor Ihsan NS, Abdul Sani SF, Looi LM, Cheah PL, Chiew SF, Pathmanathan D, et al.

Prog Biophys Mol Biol, 2023 Sep;182:59-74.
PMID: 37307955 DOI: 10.1016/j.pbiomolbio.2023.06.002

Amyloidosis is a deleterious condition caused by abnormal amyloid fibril build-up in living tissues. To date, 42 proteins that are linked to amyloid fibrils have been discovered. Amyloid fibril structure variation can affect the severity, progression rate, or clinical symptoms of amyloidosis. Since amyloid fibril build-up is the primary pathological basis for various neurodegenerative illnesses, characterization of these deadly proteins, particularly utilising optical techniques have been a focus. Spectroscopy techniques provide significant non-invasive platforms for the investigation of the structure and conformation of amyloid fibrils, offering a wide spectrum of analyses ranging from nanometric to micrometric size scales. Even though this area of study has been intensively explored, there still remain aspects of amyloid fibrillization that are not fully known, a matter hindering progress in treating and curing amyloidosis. This review aims to provide recent updates and comprehensive information on optical techniques for metabolic and proteomic characterization of β-pleated amyloid fibrils found in human tissue with thorough literature analysis of publications. Raman spectroscopy and SAXS are well established experimental methods for study of structural properties of biomaterials. With suitable models, they offer extended information for valid proteomic analysis under physiologically relevant conditions. This review points to evidence that despite limitations, these techniques are able to provide for the necessary output and proteomics indication in order to extrapolate the aetiology of amyloid fibrils for reliable diagnostic purposes. Our metabolic database may also contribute to elucidating the nature and function of the amyloid proteome in development and clearance of amyloid diseases.
EDXRF and the relative presence of K, Ca, Fe and as in amyloidogenic tissues

Mohd Nor Ihsan NS, Abdul Sani SF, Looi LM, Pathmanathan D, Cheah PL, Chiew SF, et al.

Spectrochim Acta A Mol Biomol Spectrosc, 2024 Mar 05;308:123743.
PMID: 38113556 DOI: 10.1016/j.saa.2023.123743

Trace and minor elements play crucial roles in a variety of biological processes, including amyloid fibrils formation. Mechanisms include activation or inhibition of enzymatic reactions, competition between elements and metal proteins for binding positions, also changes to the permeability of cellular membranes. These may influence carcinogenic processes, with trace and minor element concentrations in normal and amyloid tissues potentially aiding in cancer diagnosis and etiology. With the analytical capability of the spectroscopic technique X-ray fluorescence (XRF), this can be used to detect and quantify the presence of elements in amyloid characterization, two of the trace elements known to be associated with amyloid fibrils. In present work, involving samples from a total of 22 subjects, samples of normal and amyloid-containing tissues of heart, kidney, thyroid, and other tissue organs were obtained, analyzed via energy-dispersive X-ray fluorescence (EDXRF). The elemental distribution of potassium (K), calcium (Ca), arsenic (As), and iron (Fe) was examined in both normal and amyloidogenic tissues using perpetual thin slices. In amyloidogenic tissues the levels of K, Ca, and Fe were found to be less than in corresponding normal tissues. Moreover, the presence of As was only observed in amyloidogenic samples; in a few cases in which there was an absence of As, amyloid samples were found to contain Fe. Analysis of arsenic in amyloid plaques has previously been difficult, often producing contradictory results. Using the present EDXRF facility we could distinguish between amyloidogenic and normal samples, with potential correlations in respect of the presence or concentration of specific elements.
Fulltext Biogenic Salvia species synthesized silver nanoparticles with catalytic, sensing, antimicrobial, and antioxidant properties

Ihsan S, Gul H, Jamila N, Khan N, Ullah R, Bari A, et al.

Heliyon, 2024 Feb 29;10(4):e25814.
PMID: 38375246 DOI: 10.1016/j.heliyon.2024.e25814

Salvia (Lamiaceae family) is used as a brain tonic to improve cognitive function. The species including S. plebeia and S. moorcroftiana are locally used to cure hepatitis, cough, tumours, hemorrhoids, diarrhoea, common cold, flu, and asthma. To the best of authors' knowledge, no previous study has been conducted on synthesis of S. plebeia and S. moorcroftiana silver nanoparticles (SPAgNPs and SMAgNPs). The study was aimed to synthesize AgNPs from the subject species aqueous and ethanol extracts, and assess catalytic potential in degradation of standard and extracted (from yums, candies, and snacks) dyes, nitrophenols, and antibiotics. The study also aimed at AgNPs as probe in sensing metalloids and heavy metal ions including Pb2+, Cu2+, Fe3+, Ni2+, and Zn2+. From the results, it was found that Salvia aqueous extract afforded stable AgNPs in 1:9 and 1:15 (quantity of aqueous extract and silver nitrate solution concentration) whereas ethanol extract yielded AgNPs in 1:10 (quantity of ethanol extract and silver nitrate solution concentration) reacted in sunlight. The size of SPAgNPs and SMAgNPs determined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were 21.7 nm and 19.9 nm, with spherical, cylindrical, and deep hollow morphology. The synthesized AgNPs demonstrated significant potential as catalyst in dyes; Congo red (85 %), methylene blue (75 %), Rhodamine B (<50 %), nitrophenols; ortho-nitrophenol (95-98 %) and para-nitrophenol (95-98 %), dyes extracted from food samples including yums, candies, and snacks. The antibiotics (amoxicillin, doxycycline, levofloxacin) degraded up to 80 %-95 % degradation. Furthermore, the synthesized AgNPs as probe in sensing of Pb2+, Cu2+, and Fe3+ in Kabul river water, due to agglomeration, caused a significant decrease and bathochromic shift of SPR band (430 nm) when analyzed after 30 min. The Pb2+ ions was comparatively more agglomerated and chelated. Thus, the practical applicability of AgNPs in Pb2+ sensing was significant. Based on the results of this research study, the synthesized AgNPs could provide promising efficiency in wastewater treatment containing organic dyes, antibiotics, and heavy metals.
Supramolecular arrangements in human amyloid tissues using SAXS

Ihsan NSMN, Abdul Sani SF, Looi LM, Pathmanathan D, Cheah PL, Chiew SF, et al.

Biophys Chem, 2025 Jan;316:107349.
PMID: 39546937 DOI: 10.1016/j.bpc.2024.107349

Amyloid diseases are characterized by the accumulation of misfolded protein aggregates in human tissues, pose significant challenges for both diagnosis and treatment. Protein aggregations known as amyloids are linked to several neurodegenerative conditions including Alzheimer's disease, Parkinson's disease, and systemic amyloidosis. The key goal of this research is to employ Small-Angle X-ray Scattering (SAXS) to examine the supramolecular structures of amyloid aggregates in human tissues. We present the structural analysis of amyloid using SAXS, which is employed directly to analyze thin tissue samples without damaging the tissues. This technique provides size and shape information of fibrils, which can be used to generate low-resolution 2D models. The present study investigates the structural changes in amyloid fibril axial d-spacing and scattering intensity in different human tissues, including kidney, heart, thyroid, and others, while also accounting for the presence of triglycerides in these tissues. Tissue structural components were examined at momentum transfer values between q = 0.2 nm-1 and 1.5 nm-1. The d-spacing is a critical parameter in SAXS that provides information about the periodic distances between structures within a sample. From the supramolecular SAXS patterns, the axial d-spacing of fibrils in amyloid tissues is prominent and exists within the 3rd to 10th order, compared to that of healthy tissues which do not have notable peak orders. The axial period of fibrils in amyloid tissues is within the scattering vector range 57.40-64.64 nm-1 while in normal tissues the range is between 60.68 and 61.41 nm-1, which is 3.0 nm-1 smaller than amyloid-containing tissues. Differences in d-spacing are often correlate with distinct pathological mechanisms or stages of disease progression. The application of SAXS to investigate amyloid structures in human tissues has enormous potential to further knowledge of amyloid disorders. This work will open the path for novel diagnostic instruments and therapeutic strategies meant to reduce the burden of amyloid-related diseases by offering a thorough structural examination of amyloid aggregates.

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