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Bio-hydrogen production using a two-stage fermentation process

Alalayah WM, Kalil MS, Kadhum AA, Jahim JM, Jaapar SZ, Alauj NM

Pak J Biol Sci, 2009 Nov 15;12(22):1462-7.
PMID: 20180320

A two-stage fermentation process consisting of dark and photo-fermentation periods was carried out in a batch reactor. In the first stage, glucose was fermented in the dark stage using Clostridium saccharoperbutylacetonicum N1-4 (ATCC 13564; CSN1-4) to produce acetate, CO2 and H2. The acetate produced in the first stage is fermented to H2 and CO2 by Rhodobacter sphaeroides NCIMB 8253 for further hydrogen production in the second, illuminated stage. The yield of hydrogen in the first stage was about 3.10 mol H2 (mol glucose)(-1) at a glucose concentration of 10 g L(-1), pH 6 +/- 0.2 and 37 degrees C and the second stage yield was about 1.10-1.25 mol H2 (mol acetic acid)(-1) at pH 6.8 +/- 0.2 and 32 degrees C, without removal of the Clostridium CSN1-4. The overall yield of hydrogen in the two-stage process, with glucose as the main substrate was higher than single-stage fermentation.

Matched MeSH terms: Light
Enhanced Photocatalytic Performance of Sn6SiO8 Nanoparticles and Their Reduced Graphene Oxide (rGO) Nanocomposite

Gnanamoorthy G, Muthukumaran M, Varun Prasath P, Karthikeyan V, Narayanan V, Sagadevan S, et al.

J Nanosci Nanotechnol, 2020 09 01;20(9):5426-5432.
PMID: 32331114 DOI: 10.1166/jnn.2020.17814

Photocatalysts provide excellent potential for the full removal of organic chemical pollutants as an environmentally friendly technology. It has been noted that under UV-visible light irradiation, nanostructured semiconductor metal oxides photocatalysts can degrade different organic pollutants. The Sn6SiO8/rGO nanocomposite was synthesized by a hydrothermal method. The Sn6SiO8 nanoparticles hexagonal phase was confirmed by XRD and functional groups were analyzed by FT-IR spectroscopy. The bandgap of Sn6SiO8 nanoparticles (NPs) and Sn6SiO8/GO composites were found to be 2.7 eV and 2.5 eV, respectively. SEM images of samples showed that the flakes like morphology. This Sn6SiO8/rGO nanocomposite was testing for photocatalytic dye degradation of MG under visible light illumination and excellent response for the catalysts. The enhancement of photocatalytic performance was mainly attributed to the increased light absorption, charge separation efficiency and specific surface area, proved by UV-vis DRS. Further, the radical trapping experiments revealed that holes (h+) and superoxide radicals (·O-₂) were the main active species for the degradation of MG, and a possible photocatalytic mechanism was discussed.

Matched MeSH terms: Light; Lighting
Novel Ag/cellulose-doped CeO2 quantum dots for efficient dye degradation and bactericidal activity with molecular docking study

Ikram M, Hayat S, Imran M, Haider A, Naz S, Ul-Hamid A, et al.

Carbohydr Polym, 2021 Oct 01;269:118346.
PMID: 34294353 DOI: 10.1016/j.carbpol.2021.118346

In the present study, the novel Ag/cellulose nanocrystal (CNC)-doped CeO2 quantum dots (QDs) with highly efficient catalytic performance were synthesized using one pot co-precipitation technique, which were then applied in the degradation of methylene blue and ciprofloxacin (MBCF) in wastewater. Catalytic activity against MBCF dye was significantly reduced (99.3%) for (4%) Ag dopant concentration in acidic medium. For Ag/CNC-doped CeO2 vast inhibition domain of G-ve was significantly confirmed as (5.25-11.70 mm) and (7.15-13.60 mm), while medium- to high-concentration of CNC levels were calculated for G + ve (0.95 nm, 1.65 mm), respectively. Overall, (4%) Ag/CNC-doped CeO2 revealed significant antimicrobial activity against G-ve relative to G + ve at both concentrations, respectively. Furthermore, in silico molecular docking studies were performed against selected enzyme targets dihydrofolate reductase (DHFR), dihydropteroate synthase (DHPS), and DNA gyrase belonging to folate and nucleic acid biosynthetic pathway, respectively to rationalize possible mechanism behind bactericidal potential of CNC-CeO2 and Ag/CNC-CeO2.

Matched MeSH terms: Light
Experimental infection of brown-marbled grouper, Epinephelus fuscoguttatus (Forskal), with Vibrio parahaemolyticus identifies parvalbumin beta-2 subunit I, alpha-2-macroglobulin, nattectin and immunoglobulin light chain, differentially expressed in resistant grouper

Low CF, Shamsudin MN, Abdullah M, Chee HY, Aliyu-Paiko M

J Fish Dis, 2015 Jan;38(1):17-25.
PMID: 24397626 DOI: 10.1111/jfd.12195

The mechanisms through which brown-marbled grouper accomplishes resistance to infection, particularly against Vibrios, are not yet fully understood. In this study, brown-marbled grouper fingerlings were experimentally infected with Vibrio parahaemolyticus, to identify disease resistance grouper, and the serum proteome profiles were compared between resistant and susceptible candidates, via two-dimensional gel electrophoresis (2-DE). The results showed that putative parvalbumin beta-2 subunit I, alpha-2-macroglobulin, nattectin and immunoglobulin light chain proteins were among proteins that significantly overexpressed in the resistant fish as compared to the susceptible group of fish, whereas apolipoprotein E and immunoglobulin light chain proteins were observed to be differentially overexpressed in the susceptible fish. Further analysis by peptide sequencing revealed that the immunoglobulin light chain proteins identified in the resistant and susceptible groups differed in amino acid composition. Taken together, the results demonstrated for the first time that putative parvalbumin beta-2 subunit I, alpha-2-macroglobulin, nattectin and immunoglobulin light chain are among important proteins participating to effect disease resistance mechanism in fish and were overexpressed to function collectively to resist V. parahaemolyticus infection. Most of these molecules are mediators of immune response.

Matched MeSH terms: Immunoglobulin Light Chains/genetics
Selective and sensitive visible-light-prompt photoelectrochemical sensor of Cu2+ based on CdS nanorods modified with Au and graphene quantum dots

Ibrahim I, Lim HN, Huang NM, Jiang ZT, Altarawneh M

J Hazard Mater, 2020 06 05;391:122248.
PMID: 32062348 DOI: 10.1016/j.jhazmat.2020.122248

Nowadays, increasing the risk for copper leaching into the drinking water in homes, hotels and schools has become unresolved issues all around the countries such as Canada, the United States, and Malaysia. The leaching of copper in tap water is due to a combination of acidic water, damaged pipes, and corroded plumbing fixtures. To remedy this global problem, a triple interconnected structure of CdS/Au/GQDs was designed as a photo-to-electron conversion medium for a real time and selective visible-light-prompt photoelectrochemical (PEC) sensor for Cu2+ ions in real water samples. The synergistic interaction of the CdS/Au/GQDs enabled the smooth transportation of charge carriers to the charge collector and provided a channel to inhibit the charge recombination reaction. Thus, a detection limit of 2.27 nM was obtained, which is 10,000 fold lower than that of WHO's Guidelines for Drinking-water Quality (∼30 μM). The photocurrent reduction was negligible after 30 days of storage under ambient conditions, suggesting the high stability of photoelectrode. Moreover, the real-time monitoring of Cu2+ ions in real samples was performed with satisfactory results, confirming the capability of the investigated photoelectrode as the most practical detector for trace amounts of Cu2+ ions.

Matched MeSH terms: Light*
Fulltext Car license plate detection method for Malaysian plates-styles by using a web camera

Al-Ghaili, Abbas M., Syamsiah Mashohor, Abdul Rahman Ramli, Alyani Ismail

Pertanika Journal of Science & Technology, 2010;18(2):-.
MyJurnal

Recently, license plate detection has been used in many applications especially in transportation systems. Many methods have been proposed in order to detect license plates, but most of them work under restricted conditions such as fixed illumination, stationary background, and high resolution images. License plate detection plays an important role in car license plate recognition systems because it affects the accuracy and processing time of the system. This work aims to build a Car License Plate Detection (CLPD) system at a lower cost of its hardware devices and with less complexity of algorithms’ design, and then compare its performance with the local CAR Plate Extraction Technology (CARPET). As Malaysian plates have special design and they differ from other international plates, this work tries to compare two likely-design methods. The images are taken using a web camera for both the systems. One of the most important contributions in this paper is that the proposed CLPD method uses Vertical Edge Detection Algorithm (VEDA) to extract the vertical edges of plates. The proposed CLPD method can work to detect the region of car license plates. The method shows the total time of processing one 352x288 image is 47.7 ms, and it meets the requirement of real time processing. Under the experiment datasets, which were taken from real scenes, 579 out of 643 images were successfully detected. Meanwhile, the average accuracy of locating car license plate was 90%. In this work, a comparison between CARPET and the proposed CLPD method for the same tested images was done in terms of detection rate and efficiency. The results indicated that the detection rate was 92% and 84% for the CLPD method and CARPET, respectively. The results also showed that the CLPD method could work using dark images to detect license plates, whereas CARPET had failed to do so.

Matched MeSH terms: Light; Lighting
The 808 nm and 980 nm infrared laser irradiation affects spore germination and stored calcium homeostasis: A comparative study using delivery hand-pieces with standard (Gaussian) or flat-top profile

Ferrando S, Agas D, Mirata S, Signore A, De Angelis N, Ravera S, et al.

J. Photochem. Photobiol. B, Biol., 2019 Oct;199:111627.
PMID: 31536925 DOI: 10.1016/j.jphotobiol.2019.111627

Photobiomodulation relies on the transfer of energy from incident photons to a cell photoacceptor. For many years the concept of photobiomodulation and its outcome has been based upon a belief that the sole receptor within the cell was the mitochondrion. Recently, it has become apparent that there are other photoacceptors operating in different regions of the electromagnetic spectrum. Alternative photoacceptors would appear to be water and mechanisms regulating calcium homeostasis, despite a direct effect of laser photonic energy on intracellular calcium concentration outwith mitochondrial activity or influence, have not been clearly demonstrated. Therefore, to increase the knowledge of intracellular‑calcium and laser photon interaction, as well as to demonstrate differences in irradiation profiles with modern hand-pieces, we tested and compared the photobiomodulatory effect of 808 nm and 980 nm diode laser light by low- and higher-energy (60s, 100 mW/cm2, 100 mW/cm2, 500 mW/cm2, 1000 mW/cm2, 1500 mW/cm2, 2000 mW/cm2) irradiated with a "standard" (Gaussian fluence distribution) hand-piece or with a "flat-top" (uniform fluence) hand-piece. For this purpose, we used the eukaryote unicellular-model Dictyostelium discoideum. The 808 nm and 980 nm infrared laser light, at the energy tested directly affect the stored Ca2+ homeostasis, independent of the mitochondrial respiratory chain activities. From an organism perspective, the effect on Ca2+-dependent signal transduction as the regulator of spore germination in Dictyostelium, demonstrates how a cell can respond quickly to the correct laser photonic stimulus through a different cellular pathway than the known light-chromophore(mitochondria) interaction. Additionally, both hand-piece designs tested were able to photobiomodulate the D. discoideum cell; however, the hand-piece with a flat-top profile, through uniform fluence levels allows more effective and reproducible effects.

Matched MeSH terms: Low-Level Light Therapy
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
Effectiveness of Photobiomodulation Therapy on Neuropathic Pain, Nerve Conduction and Plantar Pressure Distribution in Diabetic Peripheral Neuropathy - A Systematic Review

Korada HY, Arora E, Maiya GA, Rao S, Hande M, Shetty S, et al.

Curr Diabetes Rev, 2023;19(9):e290422204244.
PMID: 37622461 DOI: 10.2174/1573399818666220429085256

BACKGROUND: Diabetic peripheral neuropathy is a severe complication of type 2 diabetes mellitus. The most common symptoms are neuropathic pain and altered sensorium due to damage to small nerve fibers. Altered plantar pressure distribution is also a major risk factor in diabetic peripheral neuropathy, leading to diabetic foot ulcers.
OBJECTIVE: The objective of this systematic review was to analyze the various studies involving photobiomodulation therapy on neuropathic pain and plantar pressure distribution in diabetic peripheral neuropathy.
METHODS: We conducted a systematic review (PubMed, Web of Science, CINAHL, and Cochrane) to summarise the evidence on photobiomodulation therapy for Diabetic Peripheral Neuropathy with type 2 diabetes mellitus. Randomized and non-randomized studies were included in the review.
RESULTS: This systematic review included eight studies in which photobiomodulation therapy showed improvement in neuropathic pain and nerve conduction velocity. It also reduces plantar pressure distribution, which is a high risk for developing foot ulcers.
CONCLUSION: We conclude that photobiomodulation therapy is an effective, non-invasive, and costefficient means to improve neuropathic pain and altered plantar pressure distribution in diabetic peripheral neuropathy.

Matched MeSH terms: Low-Level Light Therapy*
Growth and toxin production of the toxic dinoflagellate Pyrodinium bahamense var. compressum in laboratory cultures

Usup G, Kulis DM, Anderson DM

Nat. Toxins, 1994;2(5):254-62.
PMID: 7866660

Toxin production of a Malaysian isolate of the toxic red tide dinoflagellate Pyrodinium bahamense var. compressum was investigated at various stages of the batch culture growth cycle and under growth conditions affected by temperature, salinity, and light intensity variations. In all the experiments conducted, only 5 toxins were ever detected. Neosaxitoxin (NEO) and gonyautoxin V (GTX5) made up 80 mole percent or more of the cellular toxin content and saxitoxin (STX), GTX6 and decarbamoylsaxitoxin (dcSTX) made up the remainder. No gonyautoxins I-IV or C toxins were ever detected. In nutrient-replete batch cultures, toxin content rapidly peaked during early exponential phase and just as rapidly declined prior to the onset of plateau phase. Temperature had a marked effect on toxin content, which increased 3-fold as the temperature decreased from the optimum of 28 degrees C to 22 degrees C. Toxin content was constant at salinities of 24% or higher, but increased 3-fold at 20%. Toxin content decreased 2-fold and chlorophyll content increased 3-fold when light intensity was reduced from 90 to 15 microE m-2 s-1. This accompanied a 30% decrease in growth rate. Toxin composition (mole % individual toxin cell-1) remained constant throughout the course of the nutrient-replete culture and during growth at various salinities, but varied significantly with temperature and light intensity changes. At 22 degrees C, GTX5 was 25 mole % and NEO was 65 mole %, while at 34 degrees C, GTX5 increased to 55 mole % and NEO decreased proportionally to 40 mole %. When light intensity was reduced from 90 to 15 microE m-2 s-1, NEO decreased from 55 to 38 mole %, while GTX5 increased from 40 to 58 mole %. These data suggest that low light and high temperature both somehow enhance sulfo-transferase activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Matched MeSH terms: Light
The effect of aeration, agitation and light on biohydrogen production by Rhodobacter sphaeroides NCIMB 8253

Jaapar SZ, Kalil MS, Anuar N

Pak J Biol Sci, 2009 Sep 15;12(18):1253-9.
PMID: 20384278

Photo fermentation is a biological process that can be applied for hydrogen production. The process is environmental friendly which is operated under mild conditions using renewable resources. In order to increase yield of H2 produced by Rhodobacter sphaeroides, some experimental factors that may enhance H2 production were studied. The effect of operating parameters including agitation, aeration and light on hydrogen production using R. sphaeroides NCIMB 8253 was investigated. Rhodobacter sphaeroides NCIMB 8253 was grown in 100 mL serum bottle containing growth medium with maliec acid as the sole organic carbon source. The cultures were incubated anaerobically at 30 degrees C with tungsten lamp (100 W) as the light source (3.8 klux) and argon gas was purged for maintaining anaerobic condition. The results show that maximum hydrogen produced was higher (54.37 mL) in static culture with 69.98% of H2 in the total gas compared with shake culture (11.57 mL) with 57.86% of H2. By using static culture, H2 produced was five times higher compared with non-static in both aerobic and anaerobic condition. It was found that growth and H2 production with fluorescent lamp showed better results than growth and H2 production with tungsten light.

Matched MeSH terms: Light*
Fulltext Synthesis, characterization, and performance evaluation of multilayered photoanodes by introducing mesoporous carbon and TiO2 for humic acid adsorption

Hosseini S, Jahangirian H, Webster TJ, Soltani SM, Aroua MK

Int J Nanomedicine, 2016;11:3969-78.
PMID: 27574426 DOI: 10.2147/IJN.S96558

Nanostructured photoanodes were prepared via a novel combination of titanium dioxide (TiO2) nanoparticles and mesoporous carbon (C). Four different photoanodes were synthesized by sol-gel spin coating onto a glassy substrate of fluorine-doped tin oxide. The photocatalytic activities of TiO2, TiO2/C/TiO2, TiO2/C/C/TiO2, and TiO2/C/TiO2/C/TiO2 photoanodes were evaluated by exposing the synthesized photoanodes to UV-visible light. The photocurrent density observed in these photoanodes confirmed that an additional layer of mesoporous carbon could successfully increase the photocurrent density. The highest photocurrent density of ~1.022 mA cm(-2) at 1 V/saturated calomel electrode was achieved with TiO2/C/C/TiO2 under an illumination intensity of 100 mW cm(-2) from a solar simulator. The highest value of surface roughness was measured for a TiO2/C/C/TiO2 combination owing to the presence of two continuous layers of mesoporous carbon. The resulting films had a thickness ranging from 1.605 µm to 5.165 µm after the calcination process. The presence of double-layer mesoporous carbon resulted in a 20% increase in the photocurrent density compared with the TiO2/C/TiO2 combination when only a single mesoporous carbon layer was employed. The improved performance of these photoanodes can be attributed to the enhanced porosity and increased void space due to the presence of mesoporous carbon. For the first time, it has been demonstrated here that the photoelectrochemical performance of TiO2 can be improved by integrating several layers of mesoporous carbon. Comparison of the rate of removal of humic acid by the prepared photoanodes showed that the highest performance from TiO2/C/C/TiO2 was due to the highest photocurrent density generated. Therefore, this study showed that optimizing the sequence of mesoporous carbon layers can be a viable and inexpensive method for enhanced humic acid removal.

Matched MeSH terms: Light*
Effects of some environmental parameters on the reproduction and development of a tropical marine harpacticoid copepod Nitocra affinis f. californica Lang

Matias-Peralta H, Yusoff FM, Shariff M, Arshad A

Mar Pollut Bull, 2005;51(8-12):722-8.
PMID: 16291188

The effects of salinity, temperature, and light conditions on the reproduction and development of harpacticoid copepod, Nitocra affinis f. californica under controlled laboratory conditions were determined. Seven different salinity levels (5, 10, 15, 20, 25, 30, 35 ppt), four temperatures (20, 25, 30, 35 degrees C), three different light intensities (25, 56, 130 micromol m(-2) s(-1)) and photoperiods (24 h:0 h, 1 h:23 h, 12 h:12 h LD cycle) were employed in this study. The highest (p < 0.05) overall reproduction and fastest development time were achieved by copepods reared under 30-35 ppt salinity. The optimum temperature required for the maximum reproduction was 30 degrees C while under 30 degrees C and 35 degrees C the copepod development time was shortest (p < 0.05) compared to other temperature levels. The overall reproduction was highest (p < 0.05) and development rate of N. affinis was shortest (p < 0.05) under lowest light intensity (25 micromol m(-2) s(-1)). Continuous light (24 h:0 h LD) inhibited the egg production while, continuous darkness (1 h:23 h LD) and 12 h:12 h LD significantly favoured the overall reproductive activity of the female. Photoperiods 1 h:23 h and 12 h:12 h LD yielded highest total (p < 0.05) offspring female(-1) coupled with highest (p < 0.05) survival percentage. This study illustrated that although N. affinis can tolerate wide range of environmental conditions, prolonged exposure to subnormal environments affect its reproduction and development. This study showed that this species can be mass cultured for commercial purposes and has a potential to be used for toxicity studies due to its high reproductive performance fast development and a wide range of tolerance to environmental conditions.

Matched MeSH terms: Light*
Fulltext Synthesis and characterizations iron oxide carbon nanotubes nanocomposite by laser ablation for anti-microbial applications

Al-Salih M, Samsudin S, Arshad SS

J Genet Eng Biotechnol, 2021 May 18;19(1):76.
PMID: 34003402 DOI: 10.1186/s43141-021-00161-y

BACKGROUND: Environmental contamination by microbes is a major public health concern. A damp environment is one of the potential sources for microbe proliferation. Smart synthesis nanocatalytic coatings on surfaces, food, and material from different pathogen bacteria can inhibit using the Fe3O4/CNTs as anti-microbial growth can effectively curb this growing threat. In this present work, the anti-microbial efficacy of synthesis of a compound nanoparticle-containing iron oxide-multi-walled carbon nanotube was combined by laser ablation PLAL and explored the anti-bacterial action of colloidal solution of Fe3O4/CNTs NPs that was evaluated against bacteria which is classified as gram-negative (Escherichia coli (E. coli), Klebsiella pneumonia (K. pneumonia), and also that is identified as gram-positive (Streptococcus pyogenes (S .pyogenes) and Staphylococcus aureus (S. aureus) under visible light irradiation.
RESULTS: Doping of a minute fraction of iron(III) salt (0.5 mol%) in a volatile solvent (ethanol) was carried out via the sol-gel technique. Fe3O4 was further calcined at various temperatures (in the range of 500-700 °C) to evaluate the thermal stability of the Fe3O4 nanoporous oxidizer nanoparticles. The physicochemical properties of the samples were characterized through X-ray diffraction (XRD), atomic force microscopy (AFM), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), and UV-Visible spectroscopy techniques. XRD results revealed that the nanoparticles framework of Fe3O4 was maintained well up to 650 °C by the Fe dopant. UV-Vis results suggested that absorption property of combination Fe3O4/CNTs nanopowder by PLAL was enhanced and the band gap is reduced into 2.0 eV.
CONCLUSIONS: Density functional theory (DFT) studies emphasize the introduction of Fe+ and Fe2+ ions by replacing other ions in the CNT lattice, therefore creating oxygen vacancies. These further promoted anti-microbial efficiency. A significantly high bacterial inactivation that indicates results was evaluated and that the mean estimations of restraint were determined from triple assessment in every appraisal at 400 ml which represent the best anti-bacterial action against gram-positive and gram-negative microbes.

Matched MeSH terms: Light
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*
Demographic properties shape tree size distribution in a Malaysian rain forest

Kohyama TS, Potts MD, Kohyama TI, Kassim AR, Ashton PS

Am Nat, 2015 Mar;185(3):367-79.
PMID: 25674691 DOI: 10.1086/679664

Different mechanisms have been proposed to explain how vertical and horizontal heterogeneity in light conditions enhances tree species coexistence in forest ecosystems. The foliage partitioning theory proposes that differentiation in vertical foliage distribution, caused by an interspecific variation in mortality-to-growth ratio, promotes stable coexistence. In contrast, successional niche theory posits that horizontal light heterogeneity, caused by gap dynamics, enhances species coexistence through an interspecific trade-off between growth rate and survival. To distinguish between these theories of species coexistence, we analyzed tree inventory data for 370 species from the 50-ha plot in Pasoh Forest Reserve, Malaysia. We used community-wide Bayesian models to quantify size-dependent growth rate and mortality of every species. We compared the observed size distributions and the projected distributions from size-dependent demographic rates. We found that the observed size distributions were not simply correlated with the rate of population increase but were related to demographic properties such as size growth rate and mortality. Species with low relative abundance of juveniles in size distribution showed high growth rate and low mortality at small tree sizes and low per-capita recruitment rate. Overall, our findings were in accordance with those predicted by foliage partitioning theory.

Matched MeSH terms: Light*
Generation of novel n-p-n (CeO2-PPy-ZnO) heterojunction for photocatalytic degradation of micro-organic pollutants

Rajendran S, Hoang TKA, Trudeau ML, Jalil AA, Naushad M, Awual MR

Environ Pollut, 2022 Jan 01;292(Pt B):118375.
PMID: 34656681 DOI: 10.1016/j.envpol.2021.118375

Recently, hetero junction materials (p-n-p and n-p-n) have been developed for uplifting the visible light activity to destroy the harmful pollutants in wastewater. This manuscript presents a vivid description of novel n-p-n junction materials namely CeO2-PPy-ZnO. This novel n-p-n junction was applied as the photocatalyst in drifting the mobility of charge carriers and hence obtaining the better photocatalytic activity when compared with p-n and pure system. Such catalyst's syntheses were successful via the copolymerization method. The structural, morphological and optical characterization techniques were applied to identify the physio-chemical properties of the prepared materials. Additionally, the superior performance of this n-p-n nanostructured material was demonstrated in the destruction of micro organic (chlorophenol) toxic wastes under visible light. The accomplished ability of the prepared catalysts (up to 92% degradation of chlorophenol after 180 min of irradiation) and their profound degradation mechanism was explained in detail.

Matched MeSH terms: Light
Fulltext Resolution of exudative retinal detachment and regression of retinal macrocyst post-laser in Coats disease

Munira Y, Zunaina E, Azhany Y

Int Med Case Rep J, 2013;6:37-9.
PMID: 23966803 DOI: 10.2147/IMCRJ.S47769

A 15-year-old boy presented with painless progressive blurring of vision in the right eye for 1 year in duration. His visual acuity in the right eye was hand movement. The right fundus showed presence of extensive subretinal exudates at the posterior pole and a retinal macrocyst at the temporal periphery. It was associated with exudative retinal detachment at the inferior periphery of the retina. Fundus angiography revealed telangiectatic retinal vessels at the superotemporal retina. Based on clinical and angiographic findings, a diagnosis of Coats disease was made. He was treated with retinal laser photocoagulation. There was resolution of the exudative retinal detachment, reduction of subretinal exudates, and regression of the retinal macrocyst with improvement of visual acuity to 1/60 post-laser therapy.

Matched MeSH terms: Light Coagulation
Fulltext Effect of ribose-induced Maillard reaction on physical and mechanical properties of bovine gelatin films prepared by oven drying

Samira, S., Thuan-Chew Tan, T.C., Azhar, M.E.

International Food Research Journal, 2014;21(1):269-276.
MyJurnal

The effect of ribose-induced Maillard reaction on the physical and mechanical properties of gelatin films was investigated. Bovine gelatin solution (5 g/100 mL) containing glycerol and sorbitol (1:1) was mixed with 20% (R20), 40% ribose (R40), or 40% sucrose (S40) (weight % is based on gelatin dry weight) followed by heating (90ºC, 2 h) and oven drying to produce dried gelatin films. R20 and R40 films were brownish in color with lower light transparency, while CF (control film; without sugars) and S40 were colorless and had higher transparency. Tensile strength and Young Modulus values of the films were in the order; CF > R20 > R40 > S40, while elongation at break was in the order; R40 > S40 > R20 > CF. Water solubility and swelling percentages of the films were in the order; CF > S40 > R20 > R40, indicating the occurrence of insoluble “Maillard complexes” within R20 and R40 films. R20 and R40 films showed maximum light absorption at wavelength of 200 − 350 nm, whilst S40 and CF showed maximum absorbance at 200 − 250 nm. The addition of ribose yielded gelatin films with increased protection against UV light, even though the presence of sugars might had disrupted the inter connection of junction zones and decrease in mechanical properties. Occurrence of the Maillard reaction within R20 and R40 films could be the main reason for differences in physical and mechanical properties of films containing ribose that were formed from heated film-forming solutions.

Matched MeSH terms: Light
Fulltext The effect of temperature on the dispersion of α-Mangostin in pnipam microgel system

Madihah Ahmad, Bohari M. Yamin, Azwan Mat Lazim

Scientific Research Journal, 2012;9(2):0-0.
MyJurnal

α-Mangostin was extracted from the pericarp of the Malaysian local Garcinia mangostana linn., The structure was characterised by Infrared red, UV-Visible and Nuclear Magnetic Resonance spectroscopic data. The fluorescence peak at 500nm in ethanol was not observed in PNIPAM microgel solution. The increase of colloidal size of the gel in the presence of α-mangostin was studied by Dynamic Light Scattering and Transmission Electron Microscope. The size of the particle also increases with increasing temperature up to 45⁰C after which it began to shrink. The TEM micrograph at 45°C showed a uniformly structured pattern of the gel occurs in the range of the lowest solution critical temperature.

Matched MeSH terms: Dynamic Light Scattering

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