Displaying publications 141 - 160 of 317 in total

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  1. Fulltext Green Synthesis and Characterization of Silver Nanoparticles Using Spondias mombin Extract and Their Antimicrobial Activity against Biofilm-Producing Bacteria
    Samuggam S, Chinni SV, Mutusamy P, Gopinath SCB, Anbu P, Venugopal V, et al.
    Molecules, 2021 May 03;26(9).
    PMID: 34063685 DOI: 10.3390/molecules26092681
    Multidrug resistant bacteria create a challenging situation for society to treat infections. Multidrug resistance (MDR) is the reason for biofilm bacteria to cause chronic infection. Plant-based nanoparticles could be an alternative solution as potential drug candidates against these MDR bacteria, as many plants are well known for their antimicrobial activity against pathogenic microorganisms. Spondias mombin is a traditional plant which has already been used for medicinal purposes as every part of this plant has been proven to have its own medicinal values. In this research, the S. mombin extract was used to synthesise AgNPs. The synthesized AgNPs were characterized and further tested for their antibacterial, reactive oxygen species and cytotoxicity properties. The characterization results showed the synthesized AgNPs to be between 8 to 50 nm with -11.52 of zeta potential value. The existence of the silver element in the AgNPs was confirmed with the peaks obtained in the EDX spectrometry. Significant antibacterial activity was observed against selected biofilm-forming pathogenic bacteria. The cytotoxicity study with A. salina revealed the LC50 of synthesized AgNPs was at 0.81 mg/mL. Based on the ROS quantification, it was suggested that the ROS production, due to the interaction of AgNP with different bacterial cells, causes structural changes of the cell. This proves that the synthesized AgNPs could be an effective drug against multidrug resistant bacteria.
    Matched MeSH terms: Spectrum Analysis
  2. Fulltext Green chemistry synthesis of nanostructured zinc oxide powder using azadirachta indica extract for latent fingermark development
    Revathi Rajan, Yusmazura Zakaria, Shaharum Shamsuddin, Nik Fakhuruddin Nik Hassan
    Malaysian Journal of Medicine and Health Sciences, 2020;16(101):38-42.
    MyJurnal
    Introduction: Application of nano-engineered fingerprint dusting powders has been a recent trend to achieve latent fingermark development with superior ridge clarity. As such, efforts have been made to utilise natural resources to increase the sustainability of these emerging nano-engineered powders. Lithium-doped zinc oxide, primarily used as white pigments, have been previously applied to latent fingermarks with success. In the current study, nanostruc- tured zinc oxide, synthesised using neem extract as the reducing agent, was evaluated for fingermark development on non-porous surfaces. Methods: The reduction of zinc nitrate hexahydrate was facilitated by neem extract, pre- pared by boiling neem leaves in distilled water. The thick yellow paste recovered was calcined in the furnace to produce a light yellow powder. Physicochemical composition of the powder was determined using microscopic and spectroscopic instruments. The effectiveness of the powder was tested on natural fingermark deposited on several non-porous surfaces. Results: Nanostructured zinc oxide with particle size ranging in between 1 to 3 µm consisting of highly aggregated spherical particle with less than 100 nm dimensions were synthesised. Developed fingermarks revealed excellent ridge details and contrast on dark coloured surfaces. Studying the fingermark closely under scan- ning electron microscope displayed selective distribution of particle on the ridges of the fingermark residue and very minimal deposition on the fingermark valleys. Conclusion: Nanostructured zinc oxide fabricated using green chem- istry approach can be applied for the development of fingermark. Nevertheless, future works can be undertaken to enhance particle dispersity and to confer strong photoluminescence to the zinc oxide nanoparticles.
    Matched MeSH terms: Spectrum Analysis
  3. Green synthesis of graphene-silver nanocomposites and its application as a potent marine antifouling agent
    Yee MS, Khiew PS, Chiu WS, Tan YF, Kok YY, Leong CO
    Colloids Surf B Biointerfaces, 2016 Dec 01;148:392-401.
    PMID: 27639489 DOI: 10.1016/j.colsurfb.2016.09.011
    Fouling of marine surfaces has been a perpetual problem ever since the days of the early sailors. The tenacious attachment of seaweed and invertebrates to man-made surfaces, notably on ship hulls, has incurred undesirable economic losses. Graphene receives great attention in the materials world for its unique combination of physical and chemical properties. Herein, we present a novel 2-step synthesis method of graphene-silver nanocomposites which bypasses the formation of graphene oxide (GO), and produces silver nanoparticles supported on graphene sheets through a mild hydrothermal reduction process. The graphene-Ag (GAg) nanocomposite combines the antimicrobial property of silver nanoparticles and the unique structure of graphene as a support material, with potent marine antifouling properties. The GAg nanocomposite was composed of micron-scaled graphene flakes with clusters of silver nanoparticles. The silver nanoparticles were estimated to be between 72 and 86nm (SEM observations) while the crystallite size of the silver nanoparticles (AgNPs) was estimated between 1 and 5nm. The nanocomposite also exhibited the SERS effect. GAg was able to inhibit Halomonas pacifica, a model biofilm-causing microbe, from forming biofilms with as little as 1.3wt.% loading of Ag. All GAg samples displayed significant biofilm inhibition property, with the sample recording the highest Ag loading (4.9wt.% Ag) associated with a biofilm inhibition of 99.6%. Moreover, GAg displayed antiproliferative effects on marine microalgae, Dunaliella tertiolecta and Isochrysis sp. and inhibited the growth of the organisms by more than 80% after 96h. The marine antifouling properties of GAg were a synergy of the biocidal AgNPs anchored on the stable yet flexible graphene sheets, providing maximum active contact surface areas to the target organisms.
    Matched MeSH terms: Spectrum Analysis, Raman
  4. Fulltext Growth and metal uptake of spinach with application of co-compost of cat manure and spent coffee ground
    Mohd Noor Keeflee SNK, Wan Mohd Zain WNA, Mohd Nor MN, Jamion NA, Yong SK
    Heliyon, 2020 Sep;6(9):e05086.
    PMID: 33015401 DOI: 10.1016/j.heliyon.2020.e05086
    Cat manure (CM) possesses high level of nutrients for growing food crop. However, animal manure may contain toxic elements that may contaminate food crop. Spent coffee ground (SCG) may be used to reduce mobility of heavy metals and reduce crop uptake. In this study, SCG was composted with CM for 31 days to produce a co-compost (SCG-CM) for growing spinach (Spinacia oleracea). The growth rate of spinach was assessed until its maturity, and the metal uptake of spinach shoot was determined thereafter using inductively coupled plasma-optical emission spectroscopy (ICP-OES). The effect of soil treatment with SCG-CM on the height and elemental composition of spinach were compared with that of chicken manure compost (CMC). The prepared composts were primarily organic matter (72.9-81.4 % w/w) with the rest are ash (13.3-23.4 % w/w) and moisture (1.2-2.6 % w/w). Zinc content in SCG-CM (1261 ± 0.1 mg/kg) is significantly higher than that of soil and CMC (p < 0.05) and has exceeded the maximum permissible limit set by European Union Standard (2002) and the Malaysian Compost Quality Standard and Guidelines (2000). Matured spinach reached maximum plant height after 33 days. The amendment of SCG-CM significantly increased the height of spinach (32 ± 6 cm) compared to that of CMC (13 ± 1 cm) (p < 0.05). However, contents of Zn, Cu, Pb and Cd were not increased for spinach grown in the SCG-CM-amended soil, and the level of those elements are below permissible limit set by the Malaysian Food Act 1983 and Food Regulations 1985. This study shows that SCG-CM is effective in improving yield without causing accumulation of toxic trace elements in spinach.
    Matched MeSH terms: Spectrum Analysis
  5. Fulltext Health risk associated with aluminium exposure in groundwater: a cross-sectional study in an Orang Asli village in Jenderam Hilir, Selangor, Malaysia
    Lina A, Shaharuddin M
    Malaysian Journal of Public Health Medicine, 2017;17 Special(1):58-62.
    The purpose of this study was to determine aluminium (Al) concentrations in groundwater used for drinking and cooking and its related health risk among population of 28th Mile Orang Asli village in Jenderam Hilir, Selangor, Malaysia. A total of 100 respondents were recruited, comprising 51 (51.0 %) male and 49 (49.0 %) female residents. Inductively coupled plasma mass spectrometry (ICP-MS) was used to determine Al concentration, while the LAMOTTE TRACER ORP PockeTester was used to measure pH levels. Statistical Package for Social Science (SPSS) was used to analyze the data. Results showed that Al concentration ranged from 0.041 - 0.136 mg/L with a mean of 0.136 + SD 0.041 mg/L, hence the values obtained were below the standard value (0.2 mg/L). pH levels ranged from 3.82 to 5.84, with a mean of 4.163 + SD 0.411, which is acidic and below the range permitted by the health authorities. The acidic nature may have an impact on the Al concentration in the water. The Hazard Index (HI) was found to be less than 1, thus there was no health risk of Al exposure in drinking water for the respondents involved. The study area was considered safe from having health risk associated with Al exposure.
    Matched MeSH terms: Spectrum Analysis
  6. Heavy metals contamination in lipsticks and their associated health risks to lipstick consumers
    Zakaria A, Ho YB
    Regul Toxicol Pharmacol, 2015 Oct;73(1):191-5.
    PMID: 26190304 DOI: 10.1016/j.yrtph.2015.07.005
    This study aimed to determine the heavy metals (lead, cadmium, and chromium) concentration in lipsticks of different price categories sold in the Malaysian market and evaluate the potential health risks due to daily ingestion of heavy metals in lipsticks. A total of 374 questionnaires were distributed to the female staff in a public university in Malaysia in order to obtain information such as brand and price of the lipsticks, body weight, and frequency and duration of wearing lipstick. This information was important for the calculation of hazard quotient (HQ) in health risk assessment. The samples were extracted using a microwave digester and analyzed using Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). The concentrations of lead, cadmium, and chromium in lipsticks ranged from 0.77 to 15.44 mg kg(-1), 0.06-0.33 mg kg(-1), and 0.48-2.50 mg kg(-1), respectively. There was a significant difference of lead content in the lipsticks of different price categories. There was no significant non-carcinogenic health risk due to the exposure of these heavy metals through lipstick consumption for the prolonged exposure of 35 years (HQ < 1).
    Matched MeSH terms: Spectrum Analysis
  7. Hexavalent molybdenum reduction to molybdenum blue by S. marcescens strain Dr. Y6
    Shukor MY, Habib SH, Rahman MF, Jirangon H, Abdullah MP, Shamaan NA, et al.
    Appl Biochem Biotechnol, 2008 Apr;149(1):33-43.
    PMID: 18350385 DOI: 10.1007/s12010-008-8137-z
    A molybdate-reducing bacterium has been locally isolated. The bacterium reduces molybdate or Mo(6+) to molybdenum blue (molybdate oxidation states of between 5+ and 6+). Different carbon sources such as acetate, formate, glycerol, citric acid, lactose, fructose, glucose, mannitol, tartarate, maltose, sucrose, and starch were used at an initial concentration of 0.2% (w/v) in low phosphate media to study their effect on the molybdate reduction efficiency of bacterium. All of the carbon sources supported cellular growth, but only sucrose, maltose, glucose, and glycerol (in decreasing order) supported molybdate reduction after 24 h of incubation. Optimum concentration of sucrose for molybdate reduction is 1.0% (w/v) after 24 h of static incubation. Ammonium sulfate, ammonium chloride, valine, OH-proline, glutamic acid, and alanine (in the order of decreasing efficiency) supported molybdate reduction with ammonium sulfate giving the highest amount of molybdenum blue after 24 h of incubation at 0.3% (w/v). The optimum molybdate concentration that supports molybdate reduction is between 15 and 25 mM. Molybdate reduction is optimum at 35 degrees C. Phosphate at concentrations higher than 5 mM strongly inhibits molybdate reduction. The molybdenum blue produced from cellular reduction exhibits a unique absorption spectrum with a maximum peak at 865 nm and a shoulder at 700 nm. The isolate was tentatively identified as Serratia marcescens Strain Dr.Y6 based on carbon utilization profiles using Biolog GN plates and partial 16s rDNA molecular phylogeny.
    Matched MeSH terms: Spectrum Analysis
  8. High transparency iron doped indium oxide (in2—xfexo3, x = 0.0, 0.05,0.25, 0.35 and 0.45) films prepared by the sol-gel method
    Ibrahim N, Baqiah H, Abdullah M
    Sains Malaysiana, 2013;42:961-966.
    High quality indium oxide and iron doped indium oxide nanocrystalline films were prepared by the sol-gel method followed by a spin coating technique. The samples were characterized by an X-ray diffractometer, an atomic force microscopy and a UV-vis spectroscopy. All samples had good crystallinity with a preferred orientation in the (222) direction. The crystallite size increased from 12.1 nm for the pure sample to 16.1 nm for the sample with x=0.35 and then decreased to 12.1 nm for the sample with x=0.45. All samples contained nanometer grain sizes with a smooth surface. All films showed a high transmission of over 91% in the wavelength range of 200-800 nm.
    Matched MeSH terms: Spectrum Analysis
  9. Fulltext Highly exposed {001} facets of titanium dioxide modified with reduced graphene oxide for dopamine sensing
    How GT, Pandikumar A, Ming HN, Ngee LH
    Sci Rep, 2014;4:5044.
    PMID: 24853929 DOI: 10.1038/srep05044
    Titanium dioxide (TiO2) with highly exposed {001} facets was synthesized through a facile solvo-thermal method and its surface was decorated by using reduced graphene oxide (rGO) sheets. The morphology and chemical composition of the prepared rGO/TiO2 {001} nanocomposite were examined by using suitable characterization techniques. The rGO/TiO2 {001} nanocomposite was used to modify glassy carbon electrode (GCE), which showed higher electrocatalytic activity towards the oxidation of dopamine (DA) and ascorbic acid (AA), when compared to unmodified GCE. The differential pulse voltammetric studies revealed good sensitivity and selectivity nature of the rGO/TiO2 {001} nanocomposite modified GCE for the detection of DA in the presence of AA. The modified GCE exhibited a low electrochemical detection limit of 6 μM over the linear range of 2-60 μM. Overall, this work provides a simple platform for the development of GCE modified with rGO/TiO2 {001} nanocomposite with highly exposed {001} facets for potential electrochemical sensing applications.
    Matched MeSH terms: Spectrum Analysis, Raman
  10. Fulltext Hybrid Collagen Hydrogel/Chondroitin-4-Sulphate Fortified with Dermal Fibroblast Conditioned Medium for Skin Therapeutic Application
    Maarof M, Mohd Nadzir M, Sin Mun L, Fauzi MB, Chowdhury SR, Idrus RBH, et al.
    Polymers (Basel), 2021 Feb 08;13(4).
    PMID: 33567703 DOI: 10.3390/polym13040508
    The current strategy for rapid wound healing treatment involves combining a biomaterial and cell-secreted proteins or biomolecules. This study was aimed at characterizing 3-dimensional (3D) collagen hydrogels fortified with dermal fibroblast-conditioned medium (DFCM) as a readily available acellular skin substitute. Confluent fibroblasts were cultured with serum-free keratinocyte-specific medium (KM1 and KM2) and fibroblast-specific medium (FM) to obtain DFCM. Subsequently, the DFCM was mixed with collagen (Col) hydrogel and chondroitin-4-sulphate (C4S) to fabricate 3D constructs termed Col/C4S/DFCM-KM1, Col/C4S/DFCM-KM2, and Col/C4S/DFCM-FM. The constructs successfully formed soft, semi-solid and translucent hydrogels within 1 h of incubation at 37 °C with strength of <2.5 Newton (N). The Col/C4S/DFCM demonstrated significantly lower turbidity compared to the control groups. The Col/C4S/DFCM also showed a lower percentage of porosity (KM1: 35.15 ± 9.76%; KM2: 6.85 ± 1.60%; FM: 14.14 ± 7.65%) compared to the Col (105.14 ± 11.87%) and Col/C4S (143.44 ± 27.72%) constructs. There were no changes in both swelling and degradation among all constructs. Fourier transform infrared spectrometry showed that all groups consisted of oxygen-hydrogen bonds (O-H) and amide I, II, and III. In conclusion, the Col/C4S/DFCM constructs maintain the characteristics of native collagen and can synergistically deliver essential biomolecules for future use in skin therapeutic applications.
    Matched MeSH terms: Spectrum Analysis
  11. Identification and characterization of the yellow pigment synthesized by Cupriavidus sp. USMAHM13
    Ramachandran H, Iqbal MA, Amirul AA
    Appl Biochem Biotechnol, 2014 Sep;174(2):461-70.
    PMID: 25099372 DOI: 10.1007/s12010-014-1080-2
    Microbial pigments are gaining intensive attention due to increasing awareness of the toxicity of synthetic colours. In this study, a novel polymer-producing bacterium designated as Cupriavidus sp. USMAHM13 was also found to produce yellow pigment when cultivated in nutrient broth. Various parameters such as temperature, pH and ratio of culture volume to flask volume were found to influence the yellow pigment production. UV-Visible, Fourier transform infrared and (13)C-nuclear magnetic resonance analyses revealed that the crude yellow pigment might probably represent new bioactive compound in the carotenoid family. The crude yellow pigment also exhibited a wide spectrum of antimicrobial activity against Gram-negative and Gram-positive bacteria with their inhibition zones and minimal inhibitory concentrations ranged from 25 to 38 mm and from 0.63 to 2.5 mg/ml, respectively. To the best of our knowledge, this is the first report on the identification and characterization of yellow pigment produced by bacterium belonging to the genus Cupriavidus.
    Matched MeSH terms: Spectrum Analysis/methods
  12. Fulltext Imaging spectroscopy reveals the effects of topography and logging on the leaf chemistry of tropical forest canopy trees
    Swinfield T, Both S, Riutta T, Bongalov B, Elias D, Majalap-Lee N, et al.
    Glob Chang Biol, 2020 02;26(2):989-1002.
    PMID: 31845482 DOI: 10.1111/gcb.14903
    Logging, pervasive across the lowland tropics, affects millions of hectares of forest, yet its influence on nutrient cycling remains poorly understood. One hypothesis is that logging influences phosphorus (P) cycling, because this scarce nutrient is removed in extracted timber and eroded soil, leading to shifts in ecosystem functioning and community composition. However, testing this is challenging because P varies within landscapes as a function of geology, topography and climate. Superimposed upon these trends are compositional changes in logged forests, with species with more acquisitive traits, characterized by higher foliar P concentrations, more dominant. It is difficult to resolve these patterns using traditional field approaches alone. Here, we use airborne light detection and ranging-guided hyperspectral imagery to map foliar nutrient (i.e. P, nitrogen [N]) concentrations, calibrated using field measured traits, over 400 km2 of northeastern Borneo, including a landscape-level disturbance gradient spanning old-growth to repeatedly logged forests. The maps reveal that canopy foliar P and N concentrations decrease with elevation. These relationships were not identified using traditional field measurements of leaf and soil nutrients. After controlling for topography, canopy foliar nutrient concentrations were lower in logged forest than in old-growth areas, reflecting decreased nutrient availability. However, foliar nutrient concentrations and specific leaf area were greatest in relatively short patches in logged areas, reflecting a shift in composition to pioneer species with acquisitive traits. N:P ratio increased in logged forest, suggesting reduced soil P availability through disturbance. Through the first landscape scale assessment of how functional leaf traits change in response to logging, we find that differences from old-growth forest become more pronounced as logged forests increase in stature over time, suggesting exacerbated phosphorus limitation as forests recover.
    Matched MeSH terms: Spectrum Analysis
  13. Fulltext Impact of TiO₂ Nanotubes' Morphology on the Photocatalytic Degradation of Simazine Pollutant
    Meriam Suhaimy SH, Lai CW, Tajuddin HA, Samsudin EM, Johan MR
    Materials (Basel), 2018 Oct 23;11(11).
    PMID: 30360462 DOI: 10.3390/ma11112066
    There are various approaches to enhancing the catalytic properties of TiO₂, including modifying its morphology by altering the surface reactivity and surface area of the catalyst. In this study, the primary aim is to enhance the photocatalytic activity by changing the TiO₂ nanotubes' architecture. The highly ordered infrastructure is favorable for a better charge carrier transfer. It is well known that anodization affects TiO₂ nanotubes' structure by increasing the anodization duration which in turn influence the photocatalytic activity. The characterizations were conducted by FE-SEM (fiend emission scanning electron microscopy), XRD (X-ray diffraction), RAMAN (Raman spectroscopy), EDX (Energy dispersive X-ray spectroscopy), UV-Vis (Ultraviolet visible spectroscopy) and LCMS/MS/MS (liquid chromatography mass spectroscopy). We found that the morphological structure is affected by the anodization duration according to FE-SEM. The photocatalytic degradation shows a photodegradation rate of k = 0.0104 min-1. It is also found that a mineralization of Simazine by our prepared TiO₂ nanotubes leads to the formation of cyanuric acid. We propose three Simazine photodegradation pathways with several intermediates identified.
    Matched MeSH terms: Spectrum Analysis, Raman
  14. Fulltext Improving Water Permeability of Hydrophilic PVDF Membrane Prepared via Blending with Organic and Inorganic Additives for Humic Acid Separation
    Arahman N, Mulyati S, Fahrina A, Muchtar S, Yusuf M, Takagi R, et al.
    Molecules, 2019 Nov 13;24(22).
    PMID: 31766222 DOI: 10.3390/molecules24224099
    The removal of impurities from water or wastewater by the membrane filtration process has become more reliable due to good hydraulic performance and high permeate quality. The filterability of the membrane can be improved by having a material with a specific pore structure and good hydrophilic properties. This work aims at preparing a polyvinylidene fluoride (PVDF) membrane incorporated with phospholipid in the form of a 2-methacryloyloxyethyl phosphorylcholine, polymeric additive in the form of polyvinylpyrrolidone, and its combination with inorganic nanosilica from a renewable source derived from bagasse. The resulting membrane morphologies were analyzed by using scanning electron microscopy. Furthermore, atomic force microscopy was performed to analyze the membrane surface roughness. The chemical compositions of the resulting membranes were identified using Fourier transform infrared. A lab-scale cross-flow filtration system module was used to evaluate the membrane's hydraulic and separation performance by the filtration of humic acid (HA) solution as the model contaminant. Results showed that the additives improved the membrane surface hydrophilicity. All modified membranes also showed up to five times higher water permeability than the pristine PVDF, thanks to the improved structure. Additionally, all membrane samples showed HA rejections of 75-90%.
    Matched MeSH terms: Spectrum Analysis
  15. In vitro assessment of ribose modified two-step etch-and-rinse dentine adhesive
    Daood U, Tsoi JKH, Neelakantan P, Matinlinna JP, Omar HAK, Al-Nabulsi M, et al.
    Dent Mater, 2018 08;34(8):1175-1187.
    PMID: 29779627 DOI: 10.1016/j.dental.2018.05.005
    OBJECTIVE: Collagen fibrils aid in anchoring resin composite restorations to the dentine substrate. The aim of the study was to investigate effect of non-enzymatic glycation on bond strength and durability of demineralized dentine specimens in a modified two-step etch-and-rinse dentine adhesive.

    METHODS: Dentine surfaces were etched with 37% phosphoric acid, bonded with respective in vitro ethanol and acetone adhesives modified with (m/m, 0, 1%, 2% and 3% ribose), restored with restorative composite-resin, and sectioned into resin-dentine slabs and beams to be stored for 24h or 12 months in artificial saliva. Bond-strength testing was performed with bond failure analysis. Pentosidine assay was performed on demineralized ribose modified dentine specimens with HPLC sensitive fluorescent detection. The structural variations of ribose-modified dentine were analysed using TEM and human dental pulpal cells were used for cell viability. Three-point bending test of ribose-modified dentine beams were performed and depth of penetration of adhesives evaluated with micro-Raman spectroscopy. The MMP-2 and cathepsin K activities in ribose-treated dentine powder were also quantified using ELISA. Bond strength data was expressed using two-way ANOVA followed by Tukey's test. Paired T tests were used to analyse the specimens for pentosidine crosslinks. The modulus of elasticity and dentinal MMP-2 and cathepsin K concentrations was separately analyzed using one-way ANOVA.

    RESULTS: The incorporation of RB in the experimental two-step etch-and-rinse adhesive at 1% improved the adhesive bond strength without adversely affecting the degree of polymerisation. The newly developed adhesive increases the resistance of dentine collagen to degradation by inhibiting endogenous matrix metalloproteinases and cysteine cathepsins. The application of RB to acid-etched dentine helps maintain the mechanical properties.

    SIGNIFICANCE: The incorporation of 1%RB can be considered as a potential candidate stabilizing resin dentine bond.

    Matched MeSH terms: Spectrum Analysis, Raman
  16. Fulltext In vivo detection of monosodium urate crystal deposits by Raman spectroscopy-a pilot study
    Abhishek A, Curran DJ, Bilwani F, Jones AC, Towler MR, Doherty M
    Rheumatology (Oxford), 2016 Feb;55(2):379-80.
    PMID: 26342227 DOI: 10.1093/rheumatology/kev339
    Study done in England
    Matched MeSH terms: Spectrum Analysis, Raman
  17. Fulltext In-situ compositional analysis and provenance study of the historic terengganu stone (the inscribed stone “Batu Bersurat”) using neutron-induced prompt gamma-ray techniques (NIPGAT)
    Jaafar Abdullah, Roslan Yahya, Lahasen@Norman Shah Dahing, Hearie Hassan, Engku Mohd Fahmi Engku Chik, Mohamad Rabaie Shari, et al.
    Jurnal Sains Nuklear Malaysia, 2013;25(2):9-19.
    MyJurnal
    “Batu Bersurat Terengganu (inscribed stone)” is the oldest artifact with Jawi writing on it. The
    artifact proves that the Kingdom of Terengganu exist earlier than 1326 or 1386. To date, a lot of
    studies on the content of the inscription have been carried out by historians and archaeologists, but
    no scientific investigation about the material composition and its provenance has been performed.
    This paper focuses on the study of the origin of the Batu Bersurat Terengganu using NeutronInduced
    Prompt Gamma-Ray Techniques (NIPGAT). Portable NIPGAT system has been designed
    and developed based on volumetric measurement methods and it will be considered as a nondestructive
    testing. The system uses low activity of californium-252 (Cf-252) neutron radioactive
    sources, gamma ray spectroscopy and special computer software to carry out the investigation. The
    study found that the Batu Bersurat Terengganu is made of dolerite based on the elemental
    composition of the stone. Although most of the scientific data for the study of the origin are already
    obtained, but further research is still ongoing to complete the scope of this study.
    Matched MeSH terms: Spectrum Analysis
  18. In-situ measurement of temperature and alkali metal concentration in municipal solid waste incinerators using flame emission spectroscopy
    He X, Lou C, Qiao Y, Lim M
    Waste Manag, 2020 Feb 01;102:486-491.
    PMID: 31756685 DOI: 10.1016/j.wasman.2019.11.015
    In order to address slagging, fouling and high-temperature corrosion problems caused by alkali metals in Municipal Solid Waste (MSW), in-situ measurement of alkali metal in MSW incinerators is needed. The paper presents experimental measurements of temperatures and alkali metal concentrations in two MSW incinerators based on Flame Emission Spectroscopy (FES). Through the analysis of spontaneous emission spectra and a calibration procedure, the concentration of gas phase sodium (Na) and potassium (K), temperature and thermal radiation in the incinerator were in-situ measured by a portable spectral system simultaneously. Experimental results showed MSW composition has significant effect on the measured gaseous Na and K. Higher volatile content in MSW may enhance the alkali metal emission. Besides that, the released gaseous Na and K in the two incinerators are correlated with temperature in incinerators. The study provided a low cost and effective solution for in-situ measurement of temperature and alkali metal concentration in MSW incinerators.
    Matched MeSH terms: Spectrum Analysis
  19. Fulltext InSitu Anodization of WO₃-Decorated TiO₂ Nanotube Arrays for Efficient Mercury Removal
    Lee WH, Lai CW, Hamid SBA
    Materials (Basel), 2015 Aug 28;8(9):5702-5714.
    PMID: 28793530 DOI: 10.3390/ma8095270
    WO₃-decorated TiO₂ nanotube arrays were successfully synthesized using an in situ anodization method in ethylene glycol electrolyte with dissolved H₂O₂ and ammonium fluoride in amounts ranging from 0 to 0.5 wt %. Anodization was carried out at a voltage of 40 V for a duration of 60 min. By using the less stable tungsten as the cathode material instead of the conventionally used platinum electrode, tungsten will form dissolved ions (W(6+)) in the electrolyte which will then move toward the titanium foil and form a coherent deposit on the titanium foil. The fluoride ion content was controlled to determine the optimum chemical dissolution rate of TiO₂ during anodization to produce a uniform nanotubular structure of TiO₂ film. Nanotube arrays were then characterized using FESEM, EDAX, XRD, as well as Raman spectroscopy. Based on the FESEM images obtained, nanotube arrays with an average pore diameter of up to 65 nm and a length of 1.8 µm were produced. The tungsten element in the samples was confirmed by EDAX results which showed varying tungsten content from 0.22 to 2.30 at%. XRD and Raman results showed the anatase phase of TiO₂ after calcination at 400 °C for 4 h in air atmosphere. The mercury removal efficiency of the nanotube arrays was investigated by photoirradiating samples dipped in mercury chloride solution with TUV (Tube ultraviolet) 96W UV-B Germicidal light. The nanotubes with the highest aspect ratio (15.9) and geometric surface area factor (92.0) exhibited the best mercury removal performance due to a larger active surface area, which enables more Hg(2+) to adsorb onto the catalyst surface to undergo reduction to Hg⁰. The incorporation of WO₃ species onto TiO₂ nanotubes also improved the mercury removal performance due to improved charge separation and decreased charge carrier recombination because of the charge transfer from the conduction band of TiO₂ to the conduction band of WO₃.
    Matched MeSH terms: Spectrum Analysis, Raman
  20. Fulltext Indication of high lipid content in epithelial-mesenchymal transitions of breast tissues
    Sabtu SN, Sani SFA, Looi LM, Chiew SF, Pathmanathan D, Bradley DA, et al.
    Sci Rep, 2021 Feb 05;11(1):3250.
    PMID: 33547362 DOI: 10.1038/s41598-021-81426-x
    The epithelial-mesenchymal transition (EMT) is a crucial process in cancer progression and metastasis. Study of metabolic changes during the EMT process is important in seeking to understand the biochemical changes associated with cancer progression, not least in scoping for therapeutic strategies aimed at targeting EMT. Due to the potential for high sensitivity and specificity, Raman spectroscopy was used here to study the metabolic changes associated with EMT in human breast cancer tissue. For Raman spectroscopy measurements, tissue from 23 patients were collected, comprising non-lesional, EMT and non-EMT formalin-fixed and paraffin embedded breast cancer samples. Analysis was made in the fingerprint Raman spectra region (600-1800 cm-1) best associated with cancer progression biochemical changes in lipid, protein and nucleic acids. The ANOVA test followed by the Tukey's multiple comparisons test were conducted to see if there existed differences between non-lesional, EMT and non-EMT breast tissue for Raman spectroscopy measurements. Results revealed that significant differences were evident in terms of intensity between the non-lesional and EMT samples, as well as the EMT and non-EMT samples. Multivariate analysis involving independent component analysis, Principal component analysis and non-negative least square were used to analyse the Raman spectra data. The results show significant differences between EMT and non-EMT cancers in lipid, protein, and nucleic acids. This study demonstrated the capability of Raman spectroscopy supported by multivariate analysis in analysing metabolic changes in EMT breast cancer tissue.
    Matched MeSH terms: Spectrum Analysis, Raman/methods
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