MyMedR

Displaying publications 1 - 20 of 335 in total

Abstract:

Sort:

1064 nm Nd:YAG laser light affects transmembrane mitochondria respiratory chain complexes

Ravera S, Ferrando S, Agas D, De Angelis N, Raffetto M, Sabbieti MG, et al.

J Biophotonics, 2019 09;12(9):e201900101.
PMID: 31033186 DOI: 10.1002/jbio.201900101

Photobiomodulation (PBM) is a non-plant-cell manipulation through a transfer of energy by means of light sources at the non-ablative or thermal intensity. Authors showed that cytochrome-c-oxidase (complex IV) is the specific chromophore's target of PBM at the red (600-700 nm) and NIR (760-900 nm) wavelength regions. Recently, it was suggested that the infrared region of the spectrum could influence other chromospheres, despite the interaction by wavelengths higher than 900 nm with mitochondrial chromophores was not clearly demonstrated. We characterized the interaction between mitochondria respiratory chain, malate dehydrogenase, a key enzyme of Krebs cycle, and 3-hydroxyacyl-CoA dehydrogenase, an enzyme involved in the β-oxidation (two mitochondrial matrix enzymes) with the 1064 nm Nd:YAG (100mps and 10 Hz frequency mode) irradiated at the average power density of 0.50, 0.75, 1.00, 1.25 and 1.50 W/cm2 to generate the respective fluences of 30, 45, 60, 75 and 90 J/cm2 . Our results show the effect of laser light on the transmembrane mitochondrial complexes I, III, IV and V (adenosine triphosphate synthase) (window effects), but not on the extrinsic mitochondrial membrane complex II and mitochondria matrix enzymes. The effect is not due to macroscopical thermal change. An interaction of this wavelength with the Fe-S proteins and Cu-centers of respiratory complexes and with the water molecules could be supposed.

Matched MeSH terms: Low-Level Light Therapy
Fulltext A Comparative Clinical Study between Concentrated Growth Factor and Low-Level Laser Therapy in the Management of Dry Socket

Kamal A, Salman B, Razak NHA, Samsudin ABR

Eur J Dent, 2020 Oct;14(4):613-620.
PMID: 32777838 DOI: 10.1055/s-0040-1714765

OBJECTIVE: A dry socket is a well-recognized complication of wound healing following tooth extraction. Its etiology is poorly understood and commonly occur among healthy patients. As such, management strategies for dry socket has always been empirical rather than scientific with varying outcome. The aim of this study is to investigate the efficacy of concentrated growth factor (CGF) and low-level laser therapy (LLLT) and compared them to the conventional treatment in the management of dry socket.
MATERIALS AND METHODS: Sixty patients with one dry socket each, at University Dental Hospital Sharjah, were divided into three treatment groups based on their choice. In group I (n = 30), conventional treatment comprising of gentle socket curettage and saline irrigation was done. Group II (n = 15) dry sockets were treated with CGF and group III (n = 15) sockets were lased with LLLT. All dry socket patients were seen at day 0 for treatment and subsequently followed-up at 4, 7, 14, and 21 days. Pain score, perisocket inflammation, perisocket tenderness, and amount of granulation tissue formation were noted.
STATISTICAL ANALYSIS: Data were analyzed as mean values for each treatment group. Comparisons were made for statistical analysis within the group and among the three groups to rank the efficacy of treatment using one-way analysis of variance (ANOVA). Statistically significant difference is kept at p < 0.05.
RESULTS: Conventional treatment group I took more than 7 days to match the healing phase of group II CGF treated socket and group III LLLT irradiated socket (p = 0.001). When healing rate between CGF and LLLT are compared, LLLT group III showed a delay of 4 days compared with CGF in granulation tissue formation and pain control.
CONCLUSION: CGF treated socket was superior to LLLT in its ability to generate 75% granulation tissue and eliminate pain symptom by day 7 (p = 0.001).

Matched MeSH terms: Low-Level Light Therapy
Fulltext A Fast SVM-Based Tongue's Colour Classification Aided by k-Means Clustering Identifiers and Colour Attributes as Computer-Assisted Tool for Tongue Diagnosis

Kamarudin ND, Ooi CY, Kawanabe T, Odaguchi H, Kobayashi F

J Healthc Eng, 2017;2017:7460168.
PMID: 29065640 DOI: 10.1155/2017/7460168

In tongue diagnosis, colour information of tongue body has kept valuable information regarding the state of disease and its correlation with the internal organs. Qualitatively, practitioners may have difficulty in their judgement due to the instable lighting condition and naked eye's ability to capture the exact colour distribution on the tongue especially the tongue with multicolour substance. To overcome this ambiguity, this paper presents a two-stage tongue's multicolour classification based on a support vector machine (SVM) whose support vectors are reduced by our proposed k-means clustering identifiers and red colour range for precise tongue colour diagnosis. In the first stage, k-means clustering is used to cluster a tongue image into four clusters of image background (black), deep red region, red/light red region, and transitional region. In the second-stage classification, red/light red tongue images are further classified into red tongue or light red tongue based on the red colour range derived in our work. Overall, true rate classification accuracy of the proposed two-stage classification to diagnose red, light red, and deep red tongue colours is 94%. The number of support vectors in SVM is improved by 41.2%, and the execution time for one image is recorded as 48 seconds.

Matched MeSH terms: Light
Fulltext A Heuristic Approach for Optical Transceiver Placement to Optimize SNR and Illuminance Uniformities of an Optical Body Area Network

Masroor K, Jeoti V, Drieberg M, Cheab S, Rajbhandari S

Sensors (Basel), 2021 Apr 22;21(9).
PMID: 33922288 DOI: 10.3390/s21092943

The bi-directional information transfer in optical body area networks (OBANs) is crucial at all the three tiers of communication, i.e., intra-, inter-, and beyond-BAN communication, which correspond to tier-I, tier-II, and tier-III, respectively. However, the provision of uninterrupted uplink (UL) and downlink (DL) connections at tier II (inter-BAN) are extremely critical, since these links serve as a bridge between tier-I (intra-BAN) and tier-III (beyond-BAN) communication. Any negligence at this level could be life-threatening; therefore, enabling quality-of-service (QoS) remains a fundamental design issue at tier-II. Consequently, to provide QoS, a key parameter is to ensure link reliability and communication quality by maintaining a nearly uniform signal-to-noise ratio (SNR) within the coverage area. Several studies have reported the effects of transceiver related parameters on OBAN link performance, nevertheless the implications of changing transmitter locations on the SNR uniformity and communication quality have not been addressed. In this work, we undertake a DL scenario and analyze how the placement of light-emitting diode (LED) lamps can improve the SNR uniformity, regardless of the receiver position. Subsequently, we show that using the principle of reciprocity (POR) and with transmitter-receiver positions switched, the analysis is also applicable to UL, provided that the optical channel remains linear. Moreover, we propose a generalized optimal placement scheme along with a heuristic design formula to achieve uniform SNR and illuminance for DL using a fixed number of transmitters and compare it with an existing technique. The study reveals that the proposed placement technique reduces the fluctuations in SNR by 54% and improves the illuminance uniformity up to 102% as compared to the traditional approach. Finally, we show that, for very low luminous intensity, the SNR values remain sufficient to maintain a minimum bit error rate (BER) of 10-9 with on-off keying non-return-to-zero (OOK-NRZ) modulation format.

Matched MeSH terms: Light
Fulltext A Review on Graphene-Based Light Emitting Functional Devices

Junaid M, Md Khir MH, Witjaksono G, Ullah Z, Tansu N, Saheed MSM, et al.

Molecules, 2020 Sep 14;25(18).
PMID: 32937975 DOI: 10.3390/molecules25184217

In recent years, the field of nanophotonics has progressively developed. However, constant demand for the development of new light source still exists at the nanometric scale. Light emissions from graphene-based active materials can provide a leading platform for the development of two dimensional (2-D), flexible, thin, and robust light-emitting sources. The exceptional structure of Dirac's electrons in graphene, massless fermions, and the linear dispersion relationship with ultra-wideband plasmon and tunable surface polarities allows numerous applications in optoelectronics and plasmonics. In this article, we present a comprehensive review of recent developments in graphene-based light-emitting devices. Light emissions from graphene-based devices have been evaluated with different aspects, such as thermal emission, electroluminescence, and plasmons assisted emission. Theoretical investigations, along with experimental demonstration in the development of graphene-based light-emitting devices, have also been reviewed and discussed. Moreover, the graphene-based light-emitting devices are also addressed from the perspective of future applications, such as optical modulators, optical interconnects, and optical sensing. Finally, this review provides a comprehensive discussion on current technological issues and challenges related to the potential applications of emerging graphene-based light-emitting devices.

Matched MeSH terms: Light*
Fulltext A Review on Haematococcus pluvialis Bioprocess Optimization of Green and Red Stage Culture Conditions for the Production of Natural Astaxanthin

Oslan SNH, Shoparwe NF, Yusoff AH, Rahim AA, Chang CS, Tan JS, et al.

Biomolecules, 2021 02 10;11(2).
PMID: 33578851 DOI: 10.3390/biom11020256

As the most recognizable natural secondary carotenoid astaxanthin producer, the green microalga Haematococcus pluvialis cultivation is performed via a two-stage process. The first is dedicated to biomass accumulation under growth-favoring conditions (green stage), and the second stage is for astaxanthin evolution under various stress conditions (red stage). This mini-review discusses the further improvement made on astaxanthin production by providing an overview of recent works on H. pluvialis, including the valuable ideas for bioprocess optimization on cell growth, and the current stress-exerting strategies for astaxanthin pigment production. The effects of nutrient constituents, especially nitrogen and carbon sources, and illumination intensity are emphasized during the green stage. On the other hand, the significance of the nitrogen depletion strategy and other exogenous factors comprising salinity, illumination, and temperature are considered for the astaxanthin inducement during the red stage. In short, any factor that interferes with the cellular processes that limit the growth or photosynthesis in the green stage could trigger the encystment process and astaxanthin formation during the red stage. This review provides an insight regarding the parameters involved in bioprocess optimization for high-value astaxanthin biosynthesis from H. pluvialis.

Matched MeSH terms: Light; Lighting
Fulltext A brief review on free light chain assays: from conventional to current

Siti Yazmin Zahari Sham, Subashini C. Thambiah, Intan Nureslyna Samsudin

Malaysian Journal of Medicine and Health Sciences, 2017;13(2):59-62.
MyJurnal

Free light chains (FLCs) are tumour markers of monoclonal gammopathies. Detection of urinary FLC or also known as Bence-Jones protein through urinary protein and its immunofixation electrophoreses (UPE and uIFE, respectively) have been considered the gold standard for its biochemical diagnosis. This is mainly due to their superior detection limits compared to their counterpart investigations in serum. However, urinalysis is limited in many ways. The emergence of serum FLC assay with markedly improved detection limit circumvents many of these problems and has gained much importance in biochemical investigations of monoclonal gammopathies. Nevertheless, they are not without limitations. This review discusses the advantages and limitations of serum and urinary FLC assays.

Matched MeSH terms: Immunoglobulin Light Chains
A comparative enhancement of Au and Ag NPs role on radiative properties in Sm3+ doped zinc-sodium tellurite glass: Judd-Ofelt parameter

Mawlud SQ

Spectrochim Acta A Mol Biomol Spectrosc, 2019 Feb 15;209:78-84.
PMID: 30359852 DOI: 10.1016/j.saa.2018.10.032

Enhanced red and orange fluorescence emissions of Sm3+ Rare earth (RE) ions were observed in sodium‑zinc tellurite glasses embedded with silver and gold nanoparticles (NPs). The fine distribution of NPs in the glass matrix with an average diameter ~ 11.09 nm and ~3.86 nm for Ag and Au NPs respectively were confirmed by using transmission electron microscope (TEM). The embedding of Ag and Au NPs into the glass structure caused an increasing in the transition emission intensity of Sm3+ ions, which is ascribed to the progress of the presence of the localized surface Plasmon resonance (LSPR) indicating from the characteristic absorption peaks. The luminescence and absorption spectra have been discussed using a standard hypothesis Judd-Ofelt theory for a certain absorption transitions 6P3/2, 4I11/2, 6F11/2, 6F9/2, 6F7/2, 6F5/2, 6F3/2, 6H15/2, 6F1/2 and emission transitions 6H5/2, H7/2, 6H9/2 and H11/2 under 409 nm excitation of the Sm3+ ions. The decay life time curve exhibited a non-exponential behavior of the studied glass samples and the results were compared with the similar reported glasses. An efficient red and orange fluorescence emission illustrate that the Sm3+-doped sodium‑zinc tellurite embedded with Ag and Au NPs are potential materials for the laser illumination.

Matched MeSH terms: Light; Lighting
Fulltext A comparative study of adult mosquito trapping using dry ice and yeast generated carbon dioxide

Oli K, Jeffery J, Vythilingam I

Trop Biomed, 2005 Dec;22(2):249-51.
PMID: 16883295 MyJurnal

Adult mosquito collections were conducted for 12 weeks in two residential areas in Kuala Lumpur. The CDC light traps were compared using dry ice and yeast as sources of carbon dioxide attractants for mosquitoes. The efficacy of the dry ice baited trap was significant over yeast generated CO2 trap. The predominant species obtained were Culex quinquefasciatus, Stegomyia albopicta and Armigeres subalbatus.

Matched MeSH terms: Light
A highly emissive and stable zinc(ii) metal-organic framework as a host-guest chemopalette for approaching white-light-emission

Cai H, Xu LL, Lai HY, Liu JY, Ng SW, Li D

Chem Commun (Camb), 2017 Jun 27.
PMID: 28654101 DOI: 10.1039/c7cc03350h

A new adenine-containing metal-organic framework (MOF), [Zn4O(adenine)4(benzene-1,3-dicarboxylate)4Zn2] (named as ZnBDCA), was synthesized solvothermally. ZnBDCA possesses high quantum yield (>50%) and nano-channels that can encapsulate acriflavine molecules to build a host-guest chemopalette for approaching white-light emission.

Matched MeSH terms: Light
A mini-review on rare earth metal-doped TiO2 for photocatalytic remediation of wastewater

Saqib NU, Adnan R, Shah I

Environ Sci Pollut Res Int, 2016 Aug;23(16):15941-51.
PMID: 27335012 DOI: 10.1007/s11356-016-6984-7

Titanium dioxide (TiO2) has been considered a useful material for the treatment of wastewater due to its non-toxic character, chemical stability and excellent electrical and optical properties which contribute in its wide range of applications, particularly in environmental remediation technology. However, the wide band gap of TiO2 photocatalyst (anatase phase, 3.20 eV) limits its photocatalytic activity to the ultraviolet region of light. Besides that, the electron-hole pair recombination has been found to reduce the efficiency of the photocatalyst. To overcome these problems, tailoring of TiO2 surface with rare earth metals to improve its surface, optical and photocatalytic properties has been investigated by many researchers. The surface modifications with rare earth metals proved to enhance the efficiency of TiO2 photocatalyts by way of reducing the band gap by shifting the working wavelength to the visible region and inhibiting the anatase-to-rutile phase transformations. This review paper summarises the attempts on modification of TiO2 using rare earth metals describing their effect on the photocatalytic activities of the modified TiO2 photocatalyst.

Matched MeSH terms: Light
A new naturally derived photosensitizer and its phototoxicity on head and neck cancer cells

Lim SH, Lee HB, Ho AS

Photochem Photobiol, 2011 Sep-Oct;87(5):1152-8.
PMID: 21534974 DOI: 10.1111/j.1751-1097.2011.00939.x

In our screening for photosensitizers from natural resources, 15(1)-hydroxypurpurin-7-lactone ethyl methyl diester (compound 1) was isolated for the first time from an Araceae plant. To evaluate the efficacy of compound 1 as a photosensitizer for head and neck cancers, compound 1 was studied in reference to a known photosensitizer pheophorbide-a (Pha), in terms of photophysical properties, singlet oxygen generation and in in vitro experiments (intracellular uptake and phototoxicity assays) in two oral (HSC2 and HSC3) and two nasopharyngeal (HK1 and C666-1) cancer cell lines. In this study, compound 1 exhibited higher intracellular uptake over 24 h compared with Pha in both HSC3 and HK1 cells. When activated by ≥4.8 J cm(-2) of light, compound 1 was slightly more potent as a photosensitizer than Pha by consistently having marginally lower IC(50) values across different cell lines. In flow cytometry experiments to study the mechanism of photoactivated cell death in HSC3, compound 1 was observed to induce more pronounced apoptosis compared with Pha, which may have been driven by the transient G(2)/M cell cycle block which was also observed. These promising results on compound 1 warrant its further investigation as a clinically useful photodynamic therapy agent for head and neck cancer.

Matched MeSH terms: Light
A novel Sm doped Cr2O3 sesquioxide-decorated MWCNTs heterostructured Fenton-like with sonophotocatalytic activities under visible light irradiation

Eshaq G, M A, Khan MA, Alothman ZA, Sillanpää M

J Hazard Mater, 2022 03 15;426:127812.
PMID: 34844808 DOI: 10.1016/j.jhazmat.2021.127812

Novel Sm doped Cr2O3 decorated MWCNTs nanocomposite photocatalyst was successfully prepared by a facile hydrothermal method for metoprolol (MET) degradation. A heterogeneous photo -Fenton like system was formed with the addition of H2O2 for ultrasonic irradiation (US), visible light irradiation (Vis) and dual irradiation (US/Vis) systems. The intrinsic characteristics of Sm doped Cr2O3 decorated MWCNTs nanocomposite was comprehensively performed using state-of-art characterization tools. Optical studies confirmed that Sm doping shifted the absorbance of Cr2O3 towards the visible-light region, further enhanced by MWCNTs incorporation. In this study, degradation of metoprolol (MET) was investigated in the presence of Cr2O3 nanoparticles, Sm doped Cr2O3 and Sm doped Cr2O3 decorated MWCNTs nanocomposites using sonocatalysis and photocatalysis and simultaneously. Several different experimental parameters, including irradiation time, H2O2 concentration, catalyst amount, initial concentration, and pH value, were optimized. The remarkably enhanced sonophotocatalytic activity of Sm doped Cr2O3 decorated MWCNTs could be attributed to the more formation of reactive radicals and the excellent electronical property of Sm doping and MWCNTs. The rate constant of degradation using sonophotocatalytic system was even higher than the sum of rates of individual systems due to its synergistic performance based on the kinetic data. A plausible mechanism for the degradation of MET over Sm-Cr2O3/MWCNTs is also demonstrated by using active species scavenger studies and EPR spectroscopy. Our findings imply that (•OH), (h+) and (•O2-) were the reactive species responsible for the degradation of MET based on the special three-way Fenton-like mechanism and the dissociation of H2O2. The durability and stability of the nanocomposite were also performed, and the obtained results revealed that the catalysts can endure the harsh sonophotocatalytic conditions even after fifth cycles. Mineralization experiments using the optimized parameters were evaluated as well. The kinetics and the reaction mechanism with the possible reasons for the synergistic effect were presented. Identification of degraded intermediates also investigated.

Matched MeSH terms: Light
A phage-displayed single chain variable fragment that interacts with hepatitis B core antigen: library construction, selection and diagnosis

Tan GH, Yusoff K, Seow HF, Tan WS

J Clin Virol, 2007 Jan;38(1):49-56.
PMID: 17074533

Phage display is an alternative method for constructing and selecting antibodies with desired specificity towards an antigen.

Matched MeSH terms: Immunoglobulin Light Chains/genetics*; Immunoglobulin Light Chains/immunology
A practical three visit complete denture system

Ling BC

Ann R Australas Coll Dent Surg, 2000 Oct;15:66-8.
PMID: 11709981

Standard prosthodontic procedures require five visits to construct a set of complete maxillary and mandibular dentures. Various attempts have been made to reduce these procedures to four or three appointments. However, most of these techniques require the use of visible light polymerized resin as the final denture base materials. Visible light-cured resin materials have inferior physical properties and biocompatibility problems as compared with heat cured polymethylmethacrylate. This paper describes a system of complete denture construction which requires three clinical appointments instead of the usual five visits. This system is made possible by using the VLC base/tray material as the preliminary impression material as well as the application of a new biometric wax occlusion rim. It retains the use of polymethylmethacrylate as the denture base material. This system also utilizes all the procedures used in the conventional five appointment system of complete denture construction.

Matched MeSH terms: Light
A review of clinical guidelines, laboratory recommendations and external quality assurance programs for monoclonal gammopathy testing

Lim SM, Wijeratne N, Choy KW, Nguyen TTH, Setiawan L, Loh TP

Crit Rev Clin Lab Sci, 2024 Mar;61(2):107-126.
PMID: 37776896 DOI: 10.1080/10408363.2023.2257306

Monoclonal gammopathy (MG) is a spectrum of diseases ranging from the benign asymptomatic monoclonal gammopathy of undetermined significance to the malignant multiple myeloma. Clinical guidelines and laboratory recommendations have been developed to inform best practices in the diagnosis, monitoring, and management of MG. In this review, the pathophysiology, relevant laboratory testing recommended in clinical practice guidelines and laboratory recommendations related to MG testing and reporting are examined. The clinical guidelines recommend serum protein electrophoresis, serum immunofixation and serum free light chain measurement as initial screening. The laboratory recommendations omit serum immunofixation as it offers limited additional diagnostic value. The laboratory recommendations offer guidance on reporting findings beyond monoclonal protein, which was not required by the clinical guidelines. The clinical guidelines suggested monitoring total IgA concentration by turbidimetry or nephelometry method if the monoclonal protein migrates in the non-gamma region, whereas the laboratory recommendations make allowance for involved IgM and IgG. Additionally, several external quality assurance programs for MG protein electrophoresis and free light chain testing are also appraised. The external quality assurance programs show varied assessment criteria for protein electrophoresis reporting and unit of measurement. There is also significant disparity in reported monoclonal protein concentrations with wide inter-method analytical variation noted for both monoclonal protein quantification and serum free light chain measurement, however this variation appears smaller when the same method was used. Greater harmonization among laboratory recommendations and reporting format may improve clinical interpretation of MG testing.

Matched MeSH terms: Immunoglobulin Light Chains
A review of combined treatments for melasma involving energy-based devices and proposed pathogenesis-oriented combinations

Mehrabi JN, Bar-Ilan E, Wasim S, Koren A, Zusmanovitch L, Salameh F, et al.

J Cosmet Dermatol, 2022 Feb;21(2):461-472.
PMID: 33794033 DOI: 10.1111/jocd.14110

BACKGROUND: Melasma is an acquired disorder of hyperpigmentation, affecting a million individuals worldwide. Energy-based devices (EBDs) employed to treat melasma include various types of lasers, intense pulsed light (IPL), and radiofrequency (RF). Recent studies have attempted to address recalcitrant and recurring melasma by combining energy-based devices with topical or oral medications.
OBJECTIVE: This article reviews EBDs-based augmented treatment for melasma and suggests practical pathogenesis-oriented treatment regimens. Treatment algorithms are proposed to address various components of melasma.
METHODS: A systematic PubMed search was conducted acquiring information from various studies on combination treatments of melasma involving EBDs.
RESULTS: The 286 retrieved articles were filtered by title to contain at least one type of energy-based modality such as laser, IPL, or RF along with at least one other treatment method. Based on their subject matter, combinations were further categorized into the subheadings: laser plus medication, laser plus laser, and IPL- and RF-containing treatment methods.
CONCLUSION: There are many energy-based combination treatments that have been explored for mitigation of melasma including laser therapy with medication, multi-laser therapies, IPL, RF, and microneedling devices. Melasma is an exceedingly difficult condition to treat, however, choosing the appropriate tailor-made treatment combination can improve the final outcome.

Matched MeSH terms: Low-Level Light Therapy*
A review on exploration of Fe2O3 photocatalyst towards degradation of dyes and organic contaminants

Hitam CNC, Jalil AA

J Environ Manage, 2020 Mar 15;258:110050.
PMID: 31929077 DOI: 10.1016/j.jenvman.2019.110050

Photocatalytic degradation is among the promising technology for removal of various dyes and organic contaminants from environment owing to its excellent catalytic activity, low energy utilization, and low cost. As one of potential photocatalysts, Fe2O3 has emerged as an important material for degradation of numerous dyes and organic contaminants caused by its tolerable band gap, wide harvesting of visible light, good stability and recyclability. The present review thoroughly summarized the classification, synthesis route of Fe2O3 with different morphologies, and several modifications of Fe2O3 for improved photocatalytic performance. These include the incorporation with supporting materials, formation of heterojunction with other semiconductor photocatalysts, as well as the fabrication of Z-scheme. Explicitly, the other photocatalytic applications of Fe2O3, including for removal of heavy metals, reduction of CO2, evolution of H2, and N2 fixation are also deliberately discussed to further highlight the huge potential of this catalyst. Moreover, the prospects and future challenges are also comprised to expose the unscrutinized criteria of Fe2O3 photocatalyst. This review aims to contribute a knowledge transfer for providing more information on the potential of Fe2O3 photocatalyst. In the meantime, it might give an idea for utilization of this photocatalyst in other environmental remediation application.

Matched MeSH terms: Light*
Fulltext A survey on light intensity outputs of QTH, cabled and cordless LED light curing units

Athirah Ab Rahman, Adam Husein, Hany Mohamed Aly Ahmed, Dasmawati Mohamad, Wan Zaripah Wan Bakar, Manal Farea, et al.

Archives of Orofacial Sciences, 2014;9(2):85-90.
MyJurnal

Light intensity output is one of the determinants for adequate curing of visible light-cured materials. The aim of this survey was to evaluate the light intensity outputs (LIOs) of light curing units (LCUs) in dental clinics of Hospital Universiti Sains Malaysia (HUSM) and School of Dental Sciences, Universiti Sains Malaysia (USM). The respective LIOs of all functioning Quartz Tungsten Halogen (QTH) and Light Emitting Diode (LED) LCUs were tested using two light radiometers. For cordless LED LCUs, the testing procedure was done in situ and after being fully charged. Statistical analysis using Kruskal Wallis and Wilcoxon signed ranks tests were performed to compare the LIOs between groups and between the LIOs of in situ and post-charged cordless LED LCUs, respectively. The level of significance was set at 0.05 (p

Matched MeSH terms: Light; Curing Lights, Dental
A urea precursor to synthesize carbon nitride with mesoporosity for enhanced activity in the photocatalytic removal of phenol

Lee SC, Lintang HO, Yuliati L

Chem Asian J, 2012 Sep;7(9):2139-44.
PMID: 22733646 DOI: 10.1002/asia.201200383

A urea precursor was used for the first time to prepare mesoporous carbon nitride (MCN) by a thermal polymerization process with silica nanospheres as a hard template. Although the prepared MCN samples have similar structures and optical properties, it was revealed that the specific surface area, pore-size distribution, and morphology of the MCN samples depend on the initial mass ratio of urea to silica. Compared to the bulk carbon nitride (BCN) that only gave 20% phenol removal (6 h of irradiation), the activities can be enhanced up to 74% on MCN samples for photocatalytic removal of phenol under visible-light irradiation. The highest conversion was obtained on MCN with an initial mass ratio of urea to silica of 5, which has high surface area of 191 m(2) g(-1) and a nanoporous structure with uniform pore-size distribution of 7 nm. In addition to the high activity, the MCN sample also showed high photocatalytic stability.

Matched MeSH terms: Light

Filters

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links