Displaying publications 641 - 660 of 1297 in total

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  1. Biomineralized Conductive PEDOT: PSS-Coated PLA/PHBV/HA Nanofibrous Membranes
    Hassan MI, Masnawi NN, Sultana N
    ASAIO J., 2017 9 14;64(3):415-423.
    PMID: 28901994 DOI: 10.1097/MAT.0000000000000655
    Conductive materials are potential candidates for developing bone tissue engineering scaffolds as they are nontoxic and can enhance bone tissue regeneration. Their bioactivity can be enhanced by depositing biomineralization in simulated body fluid (SBF). In the current study, a composite electrospun membrane made up of poly(lactic) acid, poly(3-hydroxybutyrate-co-3-hydroxyvalerate), and hydroxyapatite was fabricated using an electrospinning method. The fabricated membranes were dip-coated with a conductive polymer solution, poly(3,4-ethylenedioxythiophene) poly(4-styrenesulfonate), to induce conductivity. Characterization of the membranes based on characteristics such as morphology, chemical bonding, and wettability was conducted using scanning electron microscopy, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, attenuated total reflectance Fourier transform infrared spectroscopy, and contact angle measurement. From the results, biomineralization of both coated and noncoated composite membranes was observed on the surface of nanofibers after 21 days in SBF. The membranes provide a superhydrophilic surface as shown by the contact angle. In conclusion, this biomimetic electrospun composite membrane could be used to further support cell growth for bone tissue engineering application.
    Matched MeSH terms: Microscopy, Electron, Scanning
  2. Fulltext Experimental and theoretical studies of Schiff bases as corrosion inhibitors
    Jamil DM, Al-Okbi AK, Al-Baghdadi SB, Al-Amiery AA, Kadhim A, Gaaz TS, et al.
    Chem Cent J, 2018 Feb 05;12(1):7.
    PMID: 29404816 DOI: 10.1186/s13065-018-0376-7
    BACKGROUND: Relatively inexpensive, stable Schiff bases, namely 3-((4-hydroxybenzylidene)amino)-2-methylquinazolin-4(3H)-one (BZ3) and 3-((4-(dimethylamino)benzylidene)amino)-2-methylquinazolin-4(3H)-one (BZ4), were employed as highly efficient inhibitors of mild steel corrosion by corrosive acid.

    FINDINGS: The inhibition efficiencies were estimated based on weight loss method. Moreover, scanning electron microscopy was used to investigate the inhibition mechanism. The synthesized Schiff bases were characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy and micro-elemental analysis. The inhibition efficiency depends on three factors: the amount of nitrogen in the inhibitor, the inhibitor concentration and the inhibitor molecular weight.

    CONCLUSIONS: Inhibition efficiencies of 96 and 92% were achieved with BZ4 and BZ3, respectively, at the maximum tested concentration. Density functional theory calculations of BZ3 and BZ4 were performed to compare the effects of hydroxyl and N,N-dimethylamino substituents on the inhibition efficiency, providing insight for designing new molecular structures that exhibit enhanced inhibition efficiencies.

    Matched MeSH terms: Microscopy, Electron, Scanning
  3. Fulltext Detection of Quinoline in G. boninense-Infected Plants Using Functionalized Multi-Walled Carbon Nanotubes: A Field Study
    Akanbi FS, Yusof NA, Abdullah J, Sulaiman Y, Hushiarian R
    Sensors (Basel), 2017 Jul 01;17(7).
    PMID: 28671561 DOI: 10.3390/s17071538
    Carbon nanotubes (CNTs) reinforced with gold nanoparticles (AuNPs) and chitosan nanoparticles (CTSNPs) were anchored on a screen-printed electrode to fabricate a multi-walled structure for the detection of quinoline. The surface morphology of the nanocomposites and the modified electrode was examined by an ultra-high resolution field emission scanning electron microscope (FESEM), and Fourier-transform infrared (FT-IR) spectroscopy was used to confirm the presence of specific functional groups on the multi-walled carbon nanotubes MWCNTs. Cyclic voltammetry (CV) and linear sweep voltammetry (LSV) were used to monitor the layer-by-layer assembly of ultra-thin films of nanocomposites on the surface of the electrode and other electrochemical characterizations. Under optimized conditions, the novel sensor displayed outstanding electrochemical reactivity towards the electro-oxidation of quinoline. The linear range was fixed between 0.0004 and 1.0 μM, with a limit of detection (LOD) of 3.75 nM. The fabricated electrode exhibited high stability with excellent sensitivity and selectivity, specifically attributable to the salient characteristics of AuNPs, CTSNPs, and MWCNTs and the synergistic inter-relationship between them. The newly developed electrode was tested in the field. The Ipa increased with an increase in the amount of quinoline solution added, and the peak potential deviated minimally, depicting the real capability of the newly fabricated electrode.
    Matched MeSH terms: Microscopy, Electron, Scanning
  4. Control of Attachment of Pseudomonas aeruginosa and Burkholderia cepacia to Surfaces by Shear Force
    Hui YW, Narayanan K, Dykes GA
    Water Environ Res, 2016 Nov 01;88(11):2040-2046.
    PMID: 26704787 DOI: 10.2175/106143016X14504669767292
      The effect of physical shearing on the attachment of six Pseudomonas aeruginosa strains and six Burkholderia cepacia strains to glass, stainless steel, polystyrene and Teflon® was determined. A significant (p < 0.05) decrease in hydrophobicity was apparent for all P. aeruginosa strains (17-36%) and B. cepacia, MS 5 (20%) after shearing. A significant (p < 0.05) decrease in attachment of some P. aeruginosa (0.2-0.5 log CFU/cm2) and B. cepacia (0.2-0.4 log CFU/cm2) strains to some surface types was apparent after shearing. Significant (p < 0.05) correlation was observed for both numbers of flagellated cells and hydrophobicity against attachment to glass, stainless steel and polystyrene for P. aeruginosa while only hydrophobicity showed significant correlation against the same surfaces for B. cepacia. Scanning electron microscopy and protein analysis showed that shearing removed surface proteins from the cells and may have led to the observed changes in hydrophobicity and attachment to abiotic surfaces.
    Matched MeSH terms: Microscopy, Electron, Scanning
  5. Fulltext Hydrolysis of native and annealed tapioca and sweet potato starches at subgelatinization temperature using a mixture of amylolytic enzymes
    Shariffa, Y.N., Uthumporn, U., Karim, A.A., Zaibunnisa, A.H
    International Food Research Journal, 2017;24(5):1925-1933.
    MyJurnal
    This study investigated the effect of annealing treatment (at 50°C for 72 h) on hydrolysis of tapioca and sweet potato starches using a raw starch hydrolyzing enzyme namely STARGEN 001 (a blend from fungal α-amylase and glucoamylase) at sub-gelatinization temperature (35°C) for 24 h. The degree of hydrolysis of the starches was evaluated based on the dextrose equivalent (DE) value. The hydrolyzed starches were then characterized in terms of its morphology, swelling power and solubility, gelatinization and pasting properties, amylose content and x-ray diffraction pattern. After 24 h of hydrolysis, annealed starches were hydrolyzed to a greater degree with higher DE value compared to native starches (40% vs 33% for tapioca; and 29% vs 24% for sweet potato starch). Scanning electron microscopy (SEM) micrographs revealed a more porous granules and rougher surface in annealed starches than their native counterparts. The swelling power and solubility of annealed starches decreased significantly. Annealing was found to affect the pasting properties of the starches appreciably and increase the starch gelatinization temperature. The amylose content in hydrolyzed annealed tapioca and sweet potato starches increased while no significant changes observed in the X-ray diffraction of those starches. This study shows that the annealing treatment can be used as a way to increase the degree of hydrolysis of tapioca and sweet potato starches at sub-gelatinization temperature using a raw starch hydrolyzing enzyme.
    Matched MeSH terms: Microscopy, Electron, Scanning
  6. Ultrastructural analysis of Apicomplexa-Like parasites in two conch species Laevistrombus canarium and canarium urceus from Johor Straits, Malaysia
    Azmi NF, Ghaffar MA, Daud HHM, Cob ZC
    J Invertebr Pathol, 2018 02;152:17-24.
    PMID: 29360442 DOI: 10.1016/j.jip.2018.01.005
    The tropical conch, Laevistrombus canarium (Linnaeus, 1758) and Canarium urceus (Linneaus, 1758) are ecologically and economically important shellfish species in Malaysia and neighboring region. Their populations, however are currently declining and this histopathological study investigates the aspect of parasitism and diseases that may affect their well-being. Conch samples were randomly collected from their natural habitat and histological sections (4-5 µm) of various organs and tissues were examined under light microscope. This was followed by ultrastructure analysis on infected tissues using transmission electron microscope (TEM). Based on the histological analysis, large numbers of gamonts, sporocysts and trophozoites of Apicomplexa-like parasites were observed in the vacuolated cells and pyramidal crypt cells of the digestive tubules, and in the digestive ducts. Furthermore, coccidian and oocysts-like Pseudoklossia sp. stages were also observed in the cells of the kidney. Apart from that, spores with cyst-like structure were observed in the digestive gland and kidney. Although the parasites were present in most of the organs analyzed, there was no obvious symptom, inflammatory response or mortality incurred on both species, which implies the possibility of a non-virulent relationship like commensalisms or mutualism. However, more investigations, including molecular studies, are needed to confirm the parasite identification and dynamics, and to further evaluate the nature of relationship between Apicomplexa parasites and their host.
    Matched MeSH terms: Microscopy, Electron, Transmission
  7. Fulltext Characterization and toxicity of citral incorporated with nanostructured lipid carrier
    Nordin N, Yeap SK, Zamberi NR, Abu N, Mohamad NE, Rahman HS, et al.
    PeerJ, 2018;6:e3916.
    PMID: 29312812 DOI: 10.7717/peerj.3916
    The nanoparticle as a cancer drug delivery vehicle is rapidly under investigation due to its promising applicability as a novel drug delivery system for anticancer agents. This study describes the development, characterization and toxicity studies of a nanostructured lipid carrier (NLC) system for citral. Citral was loaded into the NLC using high pressure homogenization methods. The characterizations of NLC-citral were then determined through various methods. Based on Transmission Electron Microscope (TEM) analysis, NLC-Citral showed a spherical shape with an average diameter size of 54.12 ± 0.30 nm and a polydipersity index of 0.224 ± 0.005. The zeta potential of NLC-Citral was -12.73 ± 0.34 mV with an entrapment efficiency of 98.9 ± 0.124%, and drug loading of 9.84 ± 0.041%. Safety profile of the formulation was examined via in vitro and in vivo routes to study its effects toward normal cells. NLC-Citral exhibited no toxic effects towards the proliferation of mice splenocytes. Moreover, no mortality and toxic signs were observed in the treated groups after 28 days of treatment. There were also no significant alterations in serum biochemical analysis for all treatments. Increase in immunomodulatory effects of treated NLC-Citral and Citral groups was verified from the increase in CD4/CD3 and CD8/CD3 T cell population in both NLC-citral and citral treated splenocytes. This study suggests that NLC is a promising drug delivery system for citral as it has the potential in sustaining drug release without inducing any toxicity.
    Matched MeSH terms: Microscopy, Electron, Transmission
  8. Fulltext Effects of Ultrasound Assisted Extraction in Conjugation with Aid of Actinidin on the Molecular and Physicochemical Properties of Bovine Hide Gelatin
    Ahmad T, Ismail A, Ahmad SA, Khalil KA, Leo TK, Awad EA, et al.
    Molecules, 2018 Mar 22;23(4).
    PMID: 29565325 DOI: 10.3390/molecules23040730
    Actinidin was used to pretreat the bovine hide and ultrasonic wave (53 kHz and 500 W) was used for the time durations of 2, 4 and 6 h at 60 °C to extract gelatin samples (UA2, UA4 and UA6, respectively). Control (UAC) gelatin was extracted using ultrasound for 6 h at 60 °C without enzyme pretreatment. There was significant (p < 0.05) increase in gelatin yield as the time duration of ultrasound treatment increased with UA6 giving the highest yield of 19.65%. Gel strength and viscosity of UAC and UA6 extracted gelatin samples were 627.53 and 502.16 g and 16.33 and 15.60 mPa.s, respectively. Longer duration of ultrasound treatment increased amino acids content of the extracted gelatin and UAC exhibited the highest content of amino acids. Progressive degradation of polypeptide chains was observed in the protein pattern of the extracted gelatin as the time duration of ultrasound extraction increased. Fourier transform infrared (FTIR) spectroscopy depicted loss of molecular order and degradation in UA6. Scanning electron microscopy (SEM) revealed protein aggregation and network formation in the gelatin samples with increasing time of ultrasound treatment. The study indicated that ultrasound assisted gelatin extraction using actinidin exhibited high yield with good quality gelatin.
    Matched MeSH terms: Microscopy, Electron, Scanning
  9. Fulltext Microencapsulation of fish oil using supercritical antisolvent process
    Karim FT, Ghafoor K, Ferdosh S, Al-Juhaimi F, Ali E, Yunus KB, et al.
    J Food Drug Anal, 2017 Jul;25(3):654-666.
    PMID: 28911651 DOI: 10.1016/j.jfda.2016.11.017
    In order to improve the encapsulation process, a newly supercritical antisolvent process was developed to encapsulate fish oil using hydroxypropyl methyl cellulose as a polymer. Three factors, namely, temperature, pressure, and feed emulsion rate were optimized using response surface methodology. The suitability of the model for predicting the optimum response value was evaluated at the conditions of temperature at 60°C, pressure at 150 bar, and feed rate at 1.36 mL/min. At the optimum conditions, particle size of 58.35 μm was obtained. The surface morphology of the micronized fish oil was also evaluated using field emission scanning electron microscopy where it showed that particles formed spherical structures with no internal voids. Moreover, in vitro release of oil showed that there are significant differences of release percentage of oil between the formulations and the results proved that there was a significant decrease in the in vitro release of oil from the powder when the polymer concentration was high.
    Matched MeSH terms: Microscopy, Electron, Scanning
  10. Selection of inactivation medium for fungal spores in clinical wastes by supercritical carbon dioxide
    Noman E, Norulaini Nik Ab Rahman N, Al-Gheethi A, Nagao H, Talip BA, Ab Kadir O
    Environ Sci Pollut Res Int, 2018 Aug;25(22):21682-21692.
    PMID: 29785605 DOI: 10.1007/s11356-018-2335-1
    The present study aimed to select the best medium for inactivation of Aspergillus fumigatus, Aspergillus spp. in section Nigri, A. niger, A. terreus var. terreus, A. tubingensis, Penicillium waksmanii, P. simplicissimum, and Aspergillus sp. strain no. 145 spores in clinical wastes by using supercritical carbon dioxide (SC-CO2). There were three types of solutions used including normal saline, seawater, distilled water, and physiological saline with 1% of methanol; each solution was tested at 5, 10, and 20 mL of the water contents. The experiments were conducted at the optimum operating parameters of supercritical carbon dioxide (30 MPa, 75 °C, 90 min). The results showed that the inactivation rate was more effective in distilled water with the presence of 1% methanol (6 log reductions). Meanwhile, the seawater decreases inactivation rate more than normal saline (4.5 vs. 5.1 log reduction). On the other hand, the experiments performed with different volumes of distilled water (5, 10, and 20 mL) indicated that A. niger spores were completely inactivated with 10 mL of distilled water. The inactivation rate of fungal spores decreased from 6 to 4.5 log as the amount of distilled water increased from 10 to 20 mL. The analysis for the spore morphology of A. fumigatus and Aspergillus spp. in section Nigri using scanning electron microscopy (SEM) has revealed the role of temperature and pressure in the SC-CO2 in the destruction of the cell walls of the spores. It can be concluded that the distilled water represent the best medium for inactivation of fungal spores in the clinical solid wastes by SC-CO2.
    Matched MeSH terms: Microscopy, Electron, Scanning
  11. Synthesis and characterization of anthill-eggshell composite adsorbent for removal of hexavalent chromium from aqueous solution
    Yusuff AS, Gbadamosi AO, Lala MA, Ngochindo JF
    Environ Sci Pollut Res Int, 2018 Jul;25(19):19143-19154.
    PMID: 29725925 DOI: 10.1007/s11356-018-2075-2
    In this study, adsorption behavior of anthill-eggshell composite (AEC) for the removal of hexavalent chromium (Cr6+) from aqueous solution was investigated. The raw AEC sample was thermally treated at 864 °C for 4 h and characterized using Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and X-ray fluorescence (XRF) techniques. The effects of adsorption process variables including initial Cr6+ concentration, contact time, and adsorbent dosage on the Cr6+ removal efficiency were investigated using central composite design (CCD) of response surface methodology (RSM). Equilibrium adsorption isotherm and kinetic were also studied. From the analysis of variance (ANOVA), the three variables proved to be significant and the optimum conditions for Cr6+ adsorption were obtained to be 150 mg/L initial Cr6+ concentration, 45.04-min contact time, and 0.5 g adsorbent dosage, which resulted in 86.21% of Cr6+ adsorbed. Equilibrium isotherm study showed that Freundlich model fitted well to the experimental data. The pseudo-second-order kinetic model appeared to better describe the experimental data. The study showed that mixed anthill-eggshell is a promising adsorbent for removing Cr6+ from aqueous solution.
    Matched MeSH terms: Microscopy, Electron, Scanning
  12. Removal of nickel from aqueous solution using supported zeolite-Y hollow fiber membranes
    Muhamad N, Abdullah N, Rahman MA, Abas KH, Aziz AA, Othman MHD, et al.
    Environ Sci Pollut Res Int, 2018 Jul;25(19):19054-19064.
    PMID: 29721796 DOI: 10.1007/s11356-018-2074-3
    This work describes the development of supported zeolite-Y membranes, prepared using the hydrothermal method, for the removal of nickel from an aqueous solution. Alumina hollow fibers prepared using the phase inversion and sintering technique were used as an inert support. The supported zeolite-Y membranes were characterized using the field emission scanning electron microscope (FESEM), X-ray diffraction (XRD), and the water permeation and rejection test. The performance of the supported zeolite-Y membranes for heavy metal removal using batch adsorption and filtration test was studied using the atomic absorption spectroscopy (AAS). The adsorption study shows that the removal of nickel was pH-dependent but affected by the presence of α-alumina. The seeded zeolite-Y membrane gave the highest adsorption capacity which was 126.2 mg g-1. This enabled the membrane to remove 63% of nickel ions from the aqueous solution within 180 min of contact time. The adsorption mechanism of nickel onto the zeolite-Y membrane was best fitted to the Freundlich isotherm. The kinetic study concluded that the adsorption was best fitted to pseudo-second-order model with higher correlation coefficient (R2 = 0.9996). The filtration study proved that the zeolite-Y membrane enabled to reduce the concentration of heavy metal at parts per billion level.
    Matched MeSH terms: Microscopy, Electron, Scanning
  13. Production of palm kernel shell-based activated carbon by direct physical activation for carbon dioxide adsorption
    Rashidi NA, Yusup S
    Environ Sci Pollut Res Int, 2019 Nov;26(33):33732-33746.
    PMID: 29740771 DOI: 10.1007/s11356-018-1903-8
    The feasibility of biomass-based activated carbons has received a huge attention due to their excellent characteristics such as inexpensiveness, good adsorption behaviour and potential to reduce a strong dependency towards non-renewable precursors. Therefore, in this research work, eco-friendly activated carbon from palm kernel shell that has been produced from one-stage physical activation by using the Box-Behnken design of Response Surface Methodology is highlighted. The effect of three input parameters-temperature, dwell time and gas flow rate-towards product yield and carbon dioxide (CO2) uptake at room temperature and atmospheric pressure are studied. Model accuracy has been evaluated through the ANOVA analysis and lack-of-fit test. Accordingly, the optimum condition in synthesising the activated carbon with adequate CO2 adsorption capacity of 2.13 mmol/g and product yield of 25.15 wt% is found at a temperature of 850 °C, holding time of 60 min and CO2 flow rate of 450 cm3/min. The synthesised activated carbon has been characterised by diverse analytical instruments including thermogravimetric analyser, scanning electron microscope, as well as N2 adsorption-desorption isotherm. The characterisation analysis indicates that the synthesised activated carbon has higher textural characteristics and porosity, together with better thermal stability and carbon content as compared to pristine palm kernel shell. Activated carbon production via one-step activation approach is economical since its carbon yield is within the industrial target, whereas CO2 uptake is comparable to the synthesised activated carbon from conventional dual-stage activation, commercial activated carbon and other published data from literature.
    Matched MeSH terms: Microscopy, Electron, Scanning
  14. Influence of Amaranth dye concentration on the efficiency of hybrid system of photocatalytic fuel cell and Fenton process
    Nordin N, Ho LN, Ong SA, Ibrahim AH, Wong YS, Lee SL, et al.
    Environ Sci Pollut Res Int, 2017 Oct;24(29):23331-23340.
    PMID: 28840563 DOI: 10.1007/s11356-017-9964-7
    A novel sustainable hybrid system of photocatalytic fuel cell (PFC) and Fenton process is an alternative wastewater treatment technology for energy-saving and efficient treatment of organic pollutants. The electrons generated from PFC photoanode are used to produce H2O2 in the Fenton reactor and react with the in situ generation of Fe2+ from sacrificial iron for hydroxyl radical formation. In this study, the effect of different initial Amaranth dye concentrations on degradation and electricity generation were investigated. ZnO/Zn photoanode was prepared by anodizing method and characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). Results revealed that the maximum power density (9.53 mW/m2) and current density (0.0178 mA/m2) were achieved at 10 mg/L of Amaranth. The correlation between dye degradation, voltage output, and kinetic photocatalytic degradation were also investigated and discussed.
    Matched MeSH terms: Microscopy, Electron, Scanning
  15. Impact of stabilizer on the environmental behavior of PVC films reinforced 1,2,4-triazole moiety
    Yousif E, Ahmed DS, Ahmed A, Abdallh M, Yusop RM, Mohammed SA
    Environ Sci Pollut Res Int, 2019 Sep;26(25):26381-26388.
    PMID: 31290046 DOI: 10.1007/s11356-019-05784-w
    A new Schiff base containing 1,2,4-triazole ring system (L) was synthesized and confirmed by 1HNMR, FTIR spectroscopy. The chemical modification of PVC with a new Schiff base (L) was synthesized to produce a homogenous blend (PVC-L). A homogenous blend (PVC-L) was added to copper chloride to produce PVC-L-Cu (II). The PVC films had been irradiated with ultraviolet light for a long period and confirmed by FTIR spectroscopy and weight loss; the surface morphology was inspected by scanning electron microscopy.
    Matched MeSH terms: Microscopy, Electron, Scanning
  16. Fulltext Synthesis and characterization of polylactide/rice husk hydrochar composite
    Nizamuddin S, Jadhav A, Qureshi SS, Baloch HA, Siddiqui MTH, Mubarak NM, et al.
    Sci Rep, 2019 Apr 01;9(1):5445.
    PMID: 30931991 DOI: 10.1038/s41598-019-41960-1
    Polymer composites are fabricated by incorporating fillers into a polymer matrix. The intent for addition of fillers is to improve the physical, mechanical, chemical and rheological properties of the composite. This study reports on a unique polymer composite using hydrochar, synthesised by microwave-assisted hydrothermal carbonization of rice husk, as filler in polylactide matrix. The polylactide/hydrochar composites were fabricated by incorporating hydrochar in polylactide at 5%, 10%, 15% and 20 wt% by melt processing in a Haake rheomix at 170 °C. Both the neat polylactide and polylactide/hydrochar composite were characterized for mechanical, structural, thermal and rheological properties. The tensile modulus of polylactide/hydrochar composites was improved from 2.63 GPa (neat polylactide) to 3.16 GPa, 3.33 GPa, 3.54 GPa, and 4.24 GPa after blending with hydrochar at 5%, 10%, 15%, and 20%, respectively. Further, the incorporation of hydrochar had little effect on storage modulus (G') and loss modulus (G″). The findings of this study reported that addition of hydrochar improves some characteristics of polylactide composites suggesting the potential of hydrochar as filler for polymer/hydrochar composites.
    Matched MeSH terms: Microscopy, Electron, Scanning
  17. Fulltext Ultra-Sensitive Humidity Sensor Based on Optical Properties of Graphene Oxide and Nano-Anatase TiO2
    Ghadiry M, Gholami M, Lai CK, Ahmad H, Chong WY
    PLoS One, 2016;11(4):e0153949.
    PMID: 27101247 DOI: 10.1371/journal.pone.0153949
    Generally, in a waveguide-based humidity sensors, increasing the relative humidity (RH) causes the cladding refractive index (RI) to increase due to cladding water absorption. However, if graphene oxide (GO) is used, a reverse phenomenon is seen due to a gap increase in graphene layers. In this paper, this interesting property is applied in order to fabricate differential humidity sensor using the difference between RI of reduced GO (rGO) and nano-anatase TiO2 in a chip. First, a new approach is proposed to prepare high quality nano-anatase TiO2 in solution form making the fabrication process simple and straightforward. Then, the resulted solutions (TiO2 and GO) are effortlessly drop casted and reduced on SU8 two channels waveguide and extensively examined against several humid conditions. Investigating the sensitivity and performance (response time) of the device, reveals a great linearity in a wide range of RH (35% to 98%) and a variation of more than 30 dB in transmitted optical power with a response time of only ~0.7 sec. The effect of coating concentration and UV treatment are studied on the performance and repeatability of the sensor and the attributed mechanisms explained. In addition, we report that using the current approach, devices with high sensitivity and very low response time of only 0.3 sec can be fabricated. Also, the proposed device was comprehensively compared with other state of the art proposed sensors in the literature and the results were promising. Since high sensitivity ~0.47dB/%RH and high dynamic performances were demonstrated, this sensor is a proper choice for biomedical applications.
    Matched MeSH terms: Microscopy, Electron, Scanning
  18. Studies on the red cell-parasite relationship
    Arnold JD, Balcerzak SP, Martin DC
    Mil Med, 1969 Sep;134(10):962-71.
    PMID: 4987072
    Matched MeSH terms: Microscopy, Electron
  19. Evaluation of structural and compositional changes on the root surface exposed to diode laser (810 nm): An In-vitro study
    Jayachandran D, Selvaraj S, Priya S, Kukkamalla MA, Senkalvarayan V
    Indian J Dent Res, 2023;34(1):19-23.
    PMID: 37417051 DOI: 10.4103/ijdr.ijdr_723_22
    BACKGROUND: The laser therapy has been used as an adjuvant for conventional periodontal disease as they exhibit a bactericidal effect on scaling and root planning by its thermal and photo disruptive effects on the pathogens. This study focuses on the structural and compositional changes induced on the root surfaces of teeth following diode laser (DL) application with increasing quantum of exposure time.

    OBJECTIVE: The objective of this study was to evaluate the structural and compositional changes on the root surface of extracted human permanent teeth after application of DLs (810 nm) with varying time interval.

    MATERIALS AND METHODS: Twenty samples of single-rooted periodontally compromised extracted teeth were utilized for this study. Root planning was done and the roughness caused by the instrumentation was measured using profilometric analysis. Then, the samples were divided into four groups, with DL application time: Group 1 - laser application for 15 s, Group 2 - laser application for 30 s, Group 3 - laser application for 45 s, and Group 4 - laser application for 60 s. A scanning electron microscope was used to examine the cemental surface and energy-dispersive X-ray analysis software assesses the compositional changes of the teeth in each group.

    RESULTS: This study reveals that on exposure of DL (810 nm) on the root surface when time of exposure increases, there were relative increases in surface irregularities and charring. There were significant changes in the chemical composition of the tooth surface.

    Matched MeSH terms: Microscopy, Electron, Scanning
  20. Fulltext Draft genome of the emerging pathogen, Kocuria marina, isolated from a wild urban rat
    Loong SK, Tan KK, Zainal N, Phoon WH, Zain SNM, AbuBakar S
    Mem Inst Oswaldo Cruz, 2017 Dec;112(12):857-859.
    PMID: 29211248 DOI: 10.1590/0074-02760170132
    Kocuria marina has recently emerged as a cause for catheter-related bloodstream infections in patients with underlying health complications. One K. marina strain was recently isolated from the lung tissues of a wild urban rat (Rattus rattus diardii) caught during rodent surveillance. Here, we present the draft genome of the first K. marina animal isolate, K. marina TRE150902.
    Matched MeSH terms: Microscopy, Electron, Transmission
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