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Fulltext Distribution of Recent Ostracoda in offshore sediment of the South China Sea

Ramlan, O., Noraswana, N. F.

Pertanika Journal of Science & Technology, 2014;22(2):433-444.
MyJurnal

A study on the distribution of Recent Ostracoda in offshore sediment was carried out around the South China Sea. A total of 30 sediment samples were taken from the sampling stations between latitude 1°48’ and 7°25’N and longitude 102°09’ and 105°16’E. From this study, 79 species of ostracods belonging to 16 families and 44 genera were identified. The dominant species was Foveoleberis cypraeoides with 937 individuals obtained. There were 13 to 43 species in total. Diversity Index, H(s), was in the range of 2.1 to 3.3, whereas the dominance values were between 4.4 and 14.7%. Several environmental parameters were measured including depth, temperature and salinity. The range values for each of these parameters are 13-72 m, 25.24-30.06o C and 27.74-34.91 ppt, respectively. The sediment texture in this study area can be categorized as sand, sandy mud, clayey mud, silty mud, silty clay, clayey sand, clayey silt and silty sand. The observations revealed that abundance and diversity of ostracod appeared to be principally controlled by depth. Two faunal assemblages were identified in terms of faunal composition, namely, shallow water (Hemikrithe orientalis, Neomonoceratina iniqua, Stigmatocythere indica, Cytherelloidea leroyi and Neocytheretta snellii) and deep water (Paracypris sp., Alataconcha pterogona, Bythocytheropteron alatum, Keijella paucipunctata and Actinocythereis scutigera). A comparative analysis showed a high degree resemblance between the study area and south-eastern Malay Peninsula (the South China Sea).

Matched MeSH terms: Aluminum Silicates
Paper-based capacitive sensors for identification and quantification of chemicals at the point of care

Hu J, Yew CT, Chen X, Feng S, Yang Q, Wang S, et al.

Talanta, 2017 Apr 01;165:419-428.
PMID: 28153277 DOI: 10.1016/j.talanta.2016.12.086

The identification and quantification of chemicals play a vital role in evaluation and surveillance of environmental health and safety. However, current techniques usually depend on costly equipment, professional staff, and/or essential infrastructure, limiting their accessibility. In this work, we develop paper-based capacitive sensors (PCSs) that allow simple, rapid identification and quantification of various chemicals from microliter size samples with the aid of a handheld multimeter. PCSs are low-cost parallel-plate capacitors (~$0.01 per sensor) assembled from layers of aluminum foil and filter paper via double-sided tape. The developed PCSs can identify different kinds of fluids (e.g., organic chemicals) and quantify diverse concentrations of substances (e.g., heavy metal ions) based on differences in dielectric properties, including capacitance, frequency spectrum, and dielectric loss tangent. The PCS-based method enables chemical identification and quantification to take place much cheaply, simply, and quickly at the point-of-care (POC), holding great promise for environmental monitoring in resource-limited settings.

Matched MeSH terms: Aluminum
Fulltext Optimisation of an electrochemical sensor based on bare gold electrode for detection of aluminium ion

Gilbert Ringgit, Shafiquzzaman Siddiquee, Suryani Saallah, Mohammad Tamrin Mohamad Lal

Borneo International Journal of Biotechnology, 2020;1(1):103-123.
MyJurnal

In this work, an electrochemical method for detection of trace amount of aluminium (Al3+), a heavy metal ion, based on a bare gold electrode (AuE) was developed. Current responses of the AuE under various type of electrolytes, redox indicators, pH, scan rate and accumulation time were investigated using cyclic voltammetry (CV) method to obtain the optimum conditions for Al3+ detection. The sensing properties of the AuE towards the target ion with different concentrations were investigated using differential pulse voltammetry (DPV) method. From the CV results, the optimal conditions for the detection of Al3+ were Tris-HCl buffer (0.1 M, pH 2) supported by 5 mM Prussian blue with scan rate and accumulation time respectively of 100 mVs−1 and 15 s. Under the optimum conditions, the DPV method was detected with different concentrations of aluminium ion ranging from 0.2 to 1.0 ppm resulted in a good linear regression r² = 0.9806. This result suggests that the optimisation of the basic parameters in electrochemical detection using AuE is crucial before further modification of the Au-electrode to improve the sensitivity and selectivity especially for the low concentration of ion detection. The developed method has a great potential for rapid detection of heavy metal ion (Al3+) in drinking water samples.

Matched MeSH terms: Aluminum
Fulltext Thermal Delamination Modelling and Evaluation of Aluminium-Glass Fibre-Reinforced Polymer Hybrid

Chow ZP, Ahmad Z, Wong KJ, Koloor SSR, Petrů M

Polymers (Basel), 2021 Feb 04;13(4).
PMID: 33557350 DOI: 10.3390/polym13040492

This paper aims to propose a temperature-dependent cohesive model to predict the delamination of dissimilar metal-composite material hybrid under Mode-I and Mode-II delamination. Commercial nonlinear finite element (FE) code LS-DYNA was used to simulate the material and cohesive model of hybrid aluminium-glass fibre-reinforced polymer (GFRP) laminate. For an accurate representation of the Mode-I and Mode-II delamination between aluminium and GFRP laminates, cohesive zone modelling with bilinear traction separation law was implemented. Cohesive zone properties at different temperatures were obtained by applying trends of experimental results from double cantilever beam and end notched flexural tests. Results from experimental tests were compared with simulation results at 30, 70 and 110 °C to verify the validity of the model. Mode-I and Mode-II FE models compared to experimental tests show a good correlation of 5.73% and 7.26% discrepancy, respectively. Crack front stress distribution at 30 °C is characterised by a smooth gradual decrease in Mode-I stress from the centre to the edge of the specimen. At 70 °C, the entire crack front reaches the maximum Mode-I stress with the exception of much lower stress build-up at the specimen's edge. On the other hand, the Mode-II stress increases progressively from the centre to the edge at 30 °C. At 70 °C, uniform low stress is built up along the crack front with the exception of significantly higher stress concentrated only at the free edge. At 110 °C, the stress distribution for both modes transforms back to the similar profile, as observed in the 30 °C case.

Matched MeSH terms: Aluminum
Fulltext Self-Fluxing Mechanism in Geopolymerization for Low-Sintering Temperature of Ceramic

Jamil NH, Abdullah MMAB, Pa FC, Mohamad H, Ibrahim WMAW, Amonpattaratkit P, et al.

Materials (Basel), 2021 Mar 10;14(6).
PMID: 33801862 DOI: 10.3390/ma14061325

Kaolin, theoretically known as having low reactivity during geopolymerization, was used as a source of aluminosilicate materials in this study. Due to this concern, it is challenging to directly produce kaolin geopolymers without pre-treatment. The addition of ground granulated blast furnace slag (GGBS) accelerated the geopolymerization process. Kaolin-GGBS geopolymer ceramic was prepared at a low sintering temperature due to the reaction of the chemical composition during the initial stage of geopolymerization. The objective of this work was to study the influence of the chemical composition towards sintering temperature of sintered kaolin-GGBS geopolymer. Kaolin-GGBS geopolymer was prepared with a ratio of solid to liquid 2:1 and cured at 60 °C for 14 days. The cured geopolymer was sintered at different temperatures: 800, 900, 1000, and 1100 °C. Sintering at 900 °C resulted in the highest compressive strength due to the formation of densified microstructure, while higher sintering temperature led to the formation of interconnected pores. The difference in the X-ray absorption near edge structure (XANES) spectra was related to the phases obtained from the X-ray diffraction analysis, such as akermanite and anothite. Thermal analysis indicated the stability of sintered kaolin-GGBS geopolymer when exposed to 1100 °C, proving that kaolin can be directly used without heat treatment in geopolymers. The geopolymerization process facilitates the stability of cured samples when directly sintered, as well as plays a significant role as a self-fluxing agent to reduce the sintering temperature when producing sintered kaolin-GGBS geopolymers.

Matched MeSH terms: Aluminum Silicates
Fulltext Elevated-Temperature Performance, Combustibility and Fire Propagation Index of Fly Ash-Metakaolin Blend Geopolymers with Addition of Monoaluminium Phosphate (MAP) and Aluminum Dihydrogen Triphosphate (ATP)

Zulkifly K, Cheng-Yong H, Yun-Ming L, Bayuaji R, Abdullah MMAB, Ahmad SB, et al.

Materials (Basel), 2021 Apr 15;14(8).
PMID: 33920865 DOI: 10.3390/ma14081973

Thermal performance, combustibility, and fire propagation of fly ash-metakaolin (FA-MK) blended geopolymer with the addition of aluminum triphosphate, ATP (Al(H2PO4)3), and monoaluminium phosphate, MAP (AlPO4) were evaluated in this paper. To prepare the geopolymer mix, fly ash and metakaolin with a ratio of 1:1 were added with ATP and MAP in a range of 0-3% by weight. The fire/heat resistance was evaluated by comparing the residual compressive strengths after the elevated temperature exposure. Besides, combustibility and fire propagation tests were conducted to examine the thermal performance and the applicability of the geopolymers as passive fire protection. Experimental results revealed that the blended geopolymers with 1 wt.% of ATP and MAP exhibited higher compressive strength and denser geopolymer matrix than control geopolymers. The effect of ATP and MAP addition was more obvious in unheated geopolymer and little improvement was observed for geopolymer subjected to elevated temperature. ATP and MAP at 3 wt.% did not help in enhancing the elevated-temperature performance of blended geopolymers. Even so, all blended geopolymers, regardless of the addition of ATP and MAP, were regarded as the noncombustible materials with negligible (0-0.1) fire propagation index.

Matched MeSH terms: Aluminum
Fulltext Solution Processed PVB/Mica Flake Coatings for the Encapsulation of Organic Solar Cells

Channa IA, Chandio AD, Rizwan M, Shah AA, Bhatti J, Shah AK, et al.

Materials (Basel), 2021 May 12;14(10).
PMID: 34065936 DOI: 10.3390/ma14102496

Organic photovoltaics (OPVs) die due to their interactions with environmental gases, i.e., moisture and oxygen, the latter being the most dangerous, especially under illumination, due to the fact that most of the active layers used in OPVs are extremely sensitive to oxygen. In this work we demonstrate solution-based effective barrier coatings based on composite of poly(vinyl butyral) (PVB) and mica flakes for the protection of poly (3-hexylthiophene) (P3HT)-based organic solar cells (OSCs) against photobleaching under illumination conditions. In the first step we developed a protective layer with cost effective and environmentally friendly methods and optimized its properties in terms of transparency, barrier improvement factor, and bendability. The developed protective layer maintained a high transparency in the visible region and improved oxygen and moisture barrier quality by the factor of ~7. The resultant protective layers showed ultra-flexibility, as no significant degradation in protective characteristics were observed after 10 K bending cycles. In the second step, a PVB/mica composite layer was applied on top of the P3HT film and subjected to photo-degradation. The P3HT films coated with PVB/mica composite showed improved stability under constant light irradiation and exhibited a loss of <20% of the initial optical density over the period of 150 h. Finally, optimized barrier layers were used as encapsulation for organic solar cell (OSC) devices. The lifetime results confirmed that the stability of the OSCs was extended from few hours to over 240 h in a sun test (65 °C, ambient RH%) which corresponds to an enhanced lifetime by a factor of 9 compared to devices encapsulated with pristine PVB.

Matched MeSH terms: Aluminum Silicates
Fulltext Toxicity and metabolism of layered double hydroxide intercalated with levodopa in a Parkinson's disease model

Kura AU, Ain NM, Hussein MZ, Fakurazi S, Hussein-Al-Ali SH

Int J Mol Sci, 2014;15(4):5916-27.
PMID: 24722565 DOI: 10.3390/ijms15045916

Layered hydroxide nanoparticles are generally biocompatible, and less toxic than most inorganic nanoparticles, making them an acceptable alternative drug delivery system. Due to growing concern over animal welfare and the expense of in vivo experiments both the public and the government are interested to find alternatives to animal testing. The toxicity potential of zinc aluminum layered hydroxide (ZAL) nanocomposite containing anti-Parkinsonian agent may be determined using a PC 12 cell model. ZAL nanocomposite demonstrated a decreased cytotoxic effect when compared to levodopa on PC12 cells with more than 80% cell viability at 100 µg/mL compared to less than 20% cell viability in a direct levodopa exposure. Neither levodopa-loaded nanocomposite nor the un-intercalated nanocomposite disturbed the cytoskeletal structure of the neurogenic cells at their IC50 concentration. Levodopa metabolite (HVA) released from the nanocomposite demonstrated the slow sustained and controlled release character of layered hydroxide nanoparticles unlike the burst uptake and release system shown with pure levodopa treatment.

Matched MeSH terms: Aluminum/adverse effects; Aluminum/pharmacology*; Aluminum/chemistry
Fulltext Simulation of forced convection in a channel with nanofluid by the lattice Boltzmann method

Sidik NA, Khakbaz M, Jahanshaloo L, Samion S, Darus AN

Nanoscale Res Lett, 2013;8(1):178.
PMID: 23594696 DOI: 10.1186/1556-276X-8-178

This paper presents a numerical study of the thermal performance of fins mounted on the bottom wall of a horizontal channel and cooled with either pure water or an Al2O3-water nanofluid. The bottom wall of the channel is heated at a constant temperature and cooled by mixed convection of laminar flow at a relatively low temperature. The results of the numerical simulation indicate that the heat transfer rate of fins is significantly affected by the Reynolds number (Re) and the thermal conductivity of the fins. The influence of the solid volume fraction on the increase of heat transfer is more noticeable at higher values of the Re.

Matched MeSH terms: Aluminum Oxide
Recovering obliterated engraved marks on aluminium surfaces by etching technique

Baharum MI, Kuppuswamy R, Rahman AA

Forensic Sci Int, 2008 May 20;177(2-3):221-7.
PMID: 18313246 DOI: 10.1016/j.forsciint.2008.01.004

A study has been made of the characteristics of restoration of obliterated engraved marks on aluminium surfaces by etching technique. By etching different reagents on 0.61mm thick sheets of aluminium (99wt%) on which some engraved marks had been erased to different depths it was found that the reagent 60% hydrochloric acid and 40% sodium hydroxide on alternate swabbing on the surfaces was found to be the most sensitive one for these metal surfaces. This reagent was able to restore marks in the above plates erased down to 0.04mm below the bottom of the engraving. The marks also presented excellent contrast with the background. This reagent was further experimented with similar aluminium surfaces, but of relatively greater thickness of 1.5mm. It was noticed that the recovery depth increased slightly to 0.06mm; this suggested the dependence of recovery depth on the thickness of the sheet metal. Further, the depth of restoration decreased in cases where the original number was erased and over which a new number was engraved; the latter results are similar to those of steel surfaces reported earlier [M.A.M. Zaili, R. Kuppuswamy, H. Harun, Restoration of engraved marks on steel surfaces by etching technique, Forensic Sci. Int. 171 (2007) 27-32].

Matched MeSH terms: Aluminum
An assessment of the pH changes and metal ions released into artificial saliva by fake orthodontic braces

Haleem R, Shafiai NAA, Noor SNFM

BMC Oral Health, 2023 Sep 16;23(1):669.
PMID: 37717000 DOI: 10.1186/s12903-023-03339-7

BACKGROUND: This present study assesses changes in the pH as well as the metal ions that fake braces release into artificial saliva (AS) using a pH meter and inductively coupled plasma atomic emission spectroscopy (ICP-AES), respectively.
METHODS: Three sets of fake archwires (AWs) and brackets (Bs) as well as a set of controls were immersed in AS and placed in an incubator shaker at 50 rpm and 37°C. At Days 0, 1, 7, 14, 21, and 28, the pH of the AS medium was measured and 3.0 ml of AS was collected and stored at -20°C for elemental analysis.
RESULTS: Significant changes in pH were observed on Days 0, 1, 7, 14, 21, and 28 in the AS of the AW group. However, these changes were only observed in the B group on Days 0 and 7. The fake samples released a large quantity of sodium (Na), potassium (K), and calcium (Ca) ions, at concentrations exceeding 100 mg/L, post-28 days of immersion. The control and fake braces samples released other ions; such as lithium (Li), magnesium (Mg), barium (Ba), chromium (Cr), copper (Cu), lead (Pb), and aluminium (Al); at concentrations that did not exceed 10 mg/L.
CONCLUSIONS: The pH of the AS of all the samples increased post-incubation. Only 10 ions; namely, Na, Li, K, Mg, Ca, Ba, Cr, Cu, Pb, and Al; were detected in the AS.

Matched MeSH terms: Aluminum
Fulltext Urinary aluminium and its association with autism spectrum disorder in urban preschool children in Malaysia

Abd Wahil MS, Ja'afar MH, Md Isa Z

PeerJ, 2023;11:e15132.
PMID: 37197586 DOI: 10.7717/peerj.15132

BACKGROUND: The presence of aluminium (Al) in the human body may impact brain neurodevelopment and function, and it is thought to contribute to autism spectrum disease (ASD). The main objective of this study was to assess the association between urinary Al and the development of ASD among Malaysian preschool children in the urban city of Kuala Lumpur.
METHOD: This was an unmatched case-control study in which children with ASD were recruited from an autism early intervention center and typically developed (TD) children were recruited from government-run nurseries and preschools. Urine samples were collected at home, assembled temporarily at study locations, and transported to the laboratory within 24 h. The Al concentration in the children's urine samples was determined using inductively coupled plasma mass spectrometry (ICP-MS).
RESULT: A total of 155 preschool children; 81 ASD children and 74 TD children, aged 3 to 6 years, were enlisted in the study. This study demonstrated that ASD children had significantly higher urinary Al levels than TD children (median (interquartile range (IQR): 2.89 (6.77) µg/dL versus 0.96 (2.95) µg/dL) (p 1, p

Matched MeSH terms: Aluminum
Fulltext Modified smoothed particle hydrodynamics (MSPH) for the analysis of centrifugally assisted TiC-Fe-Al2O3 combustion synthesis

Hassan MA, Mahmoodian R, Hamdi M

Sci Rep, 2014;4:3724.
PMID: 24430621 DOI: 10.1038/srep03724

A modified smoothed particle hydrodynamic (MSPH) computational technique was utilized to simulate molten particle motion and infiltration speed on multi-scale analysis levels. The radial velocity and velocity gradient of molten alumina, iron infiltration in the TiC product and solidification rate, were predicted during centrifugal self-propagating high-temperature synthesis (SHS) simulation, which assisted the coating process by MSPH. The effects of particle size and temperature on infiltration and solidification of iron and alumina were mainly investigated. The obtained results were validated with experimental microstructure evidence. The simulation model successfully describes the magnitude of iron and alumina diffusion in a centrifugal thermite SHS and Ti + C hybrid reaction under centrifugal acceleration.

Matched MeSH terms: Aluminum Oxide
Fulltext Effects of different tube potentials and iodine concentrations on image enhancement, contrast-to-noise ratio and noise in micro-CT images: a phantom study

Abdul Razak HR, Shaffiq Said Rahmat SM, Md Saad WM

Quant Imaging Med Surg, 2013 Oct;3(5):256-61.
PMID: 24273743 DOI: 10.3978/j.issn.2223-4292.2013.10.04

The study aimed to investigate the effects of different tube potentials and concentrations of iodinated contrast media (CM) on the image enhancement, contrast-to-noise ratio (CNR) and noise in micro-computed tomography (µCT) images. A phantom containing of five polyethylene tube was filled with 2 mL of deionized water and iodinated CM (Omnipaque 300 mgI/mL) at four different concentrations: 5, 10, 15, and 20 mol/L, respectively. The phantom was scanned with a µCT machine (SkyScan 1176) using various tube potentials: 40, 50, 60, 70, 80, and 90 kVp, a fixed tube current; 100 µA, and filtration of 0.2 mm aluminum (Al). The percentage difference of image enhancement, CNR and noise of all images, acquired at different kVps and concentrations, were calculated. The image enhancement, CNR and noise curves with respect to tube potential and concentration were plotted and analysed. The highest image enhancement was found at the lowest tube potential of 40 kVp. At this kVp setting, the percentage difference of image enhancement [Hounsfield Unit (HU) of 20 mol/L iodine concentration over HU of deionized water] was 43%. By increasing the tube potential, it resulted with the reduction of HU, where only 17.5% different were noticed for 90 kVp. Across all iodine concentrations (5-20 M), CNR peaked at 80 kVp and then these values showed a slight decreasing pattern, which might be due insufficient tube current compensation. The percentage difference of image noise obtained at 40 and 90 kVp was 72.4%. Lower tube potential setting results in higher image enhancement (HU) in conjunction with increasing concentration of iodinated CM. Overall, the tube potential increment will substantially improve CNR and reduce image noise.

Matched MeSH terms: Aluminum
Synthesis of fatty acid methyl ester from the transesterification of high- and low-acid-content crude palm oil (Elaeis guineensis) and karanj oil (Pongamia pinnata) over a calcium-lanthanum-aluminum mixed-oxides catalyst

Syamsuddin Y, Murat MN, Hameed BH

Bioresour Technol, 2016 Aug;214:248-52.
PMID: 27136612 DOI: 10.1016/j.biortech.2016.04.083

The synthesis of fatty acid methyl ester (FAME) from the high- and low-acid-content feedstock of crude palm oil (CPO) and karanj oil (KO) was conducted over CaO-La2O3-Al2O3 mixed-oxide catalyst. Various reaction parameters were investigated using a batch reactor to identify the best reaction condition that results in the highest FAME yield for each type of oil. The transesterification of CPO resulted in a 97.81% FAME yield with the process conditions of 170°C reaction temperature, 15:1 DMC-to-CPO molar ratio, 180min reaction time, and 10wt.% catalyst loading. The transesterification of KO resulted in a 96.77% FAME yield with the conditions of 150°C reaction temperature, 9:1 DMC-to-KO molar ratio, 180min reaction time, and 5wt.% catalyst loading. The properties of both products met the ASTM D6751 and EN 14214 standard requirements. The above results showed that the CaO-La2O3-Al2O3 mixed-oxide catalyst was suitable for high- and low-acid-content vegetable oil.

Matched MeSH terms: Aluminum Oxide
Fulltext Transport and retention of engineered Al2O3, TiO2, and SiO2 nanoparticles through various sedimentary rocks

Bayat AE, Junin R, Shamshirband S, Chong WT

Sci Rep, 2015;5:14264.
PMID: 26373598 DOI: 10.1038/srep14264

Engineered aluminum oxide (Al2O3), titanium dioxide (TiO2), and silicon dioxide (SiO2) nanoparticles (NPs) are utilized in a broad range of applications; causing noticeable quantities of these materials to be released into the environment. Issues of how and where these particles are distributed into the subsurface aquatic environment remain as major challenges for those in environmental engineering. In this study, transport and retention of Al2O3, TiO2, and SiO2 NPs through various saturated porous media were investigated. Vertical columns were packed with quartz-sand, limestone, and dolomite grains. The NPs were introduced as a pulse suspended in aqueous solutions and breakthrough curves in the column outlet were generated using an ultraviolet-visible spectrophotometer. It was found that Al2O3 and TiO2 NPs are easily transported through limestone and dolomite porous media whereas NPs recoveries were achieved two times higher than those found in the quartz-sand. The highest and lowest SiO2-NPs recoveries were also achieved from the quartz-sand and limestone columns, respectively. The experimental results closely replicated the general trends predicted by the filtration and DLVO calculations. Overall, NPs mobility through a porous medium was found to be strongly dependent on NP surface charge, NP suspension stability against deposition, and porous medium surface charge and roughness.

Matched MeSH terms: Aluminum Oxide
Key indicator tools for shallow slope failure assessment using soil chemical property signatures and soil colour variables

Othman R, Hasni SI, Baharuddin ZM, Hashim KSH, Mahamod LH

Environ Sci Pollut Res Int, 2017 Oct;24(29):22861-22872.
PMID: 28721625 DOI: 10.1007/s11356-017-9715-9

Slope failure has become a major concern in Malaysia due to the rapid development and urbanisation in the country. It poses severe threats to any highway construction industry, residential areas, natural resources and tourism activities. The extent of damages that resulted from this catastrophe can be lessened if a long-term early warning system to predict landslide prone areas is implemented. Thus, this study aims to characterise the relationship between Oxisols properties and soil colour variables to be manipulated as key indicators to forecast shallow slope failure. The concentration of each soil property in slope soil was evaluated from two different localities that consist of 120 soil samples from stable and unstable slopes located along the North-South Highway (PLUS) and East-West Highway (LPT). Analysis of variance established highly significant difference (P

Matched MeSH terms: Aluminum Silicates/chemistry*
Effect of Surface Treatments on the Bond Strength to Turkom-Cera All-ceramic Material

Razak AA, Abu-Hassan MI, Al-Makramani BM, Al-Sanabani FA, Al-Shami IZ, Almansour HM

J Contemp Dent Pract, 2016 Nov 01;17(11):920-925.
PMID: 27965501

AIM: The aim of this study was to evaluate the effect of surface treatments on shear bond strength (SBS) of Turkom-Cera (Turkom-Ceramic (M) Sdn. Bhd., Puchong, Malaysia) all-ceramic material cemented with resin cement Panavia-F (Kuraray Medical Inc., Okayama, Japan).
MATERIALS AND METHODS: Forty Turkom-Cera ceramic disks (10 mm × 3 mm) were prepared and randomly divided into four groups. The disks were wet ground to 1000-grit and subjected to four surface treatments: (1) No treatment (Control), (2) sandblasting, (3) silane application, and (4) sandblasting + silane. The four groups of 10 specimens each were bonded with Panavia-F resin cement according to manufacturer's recommendations. The SBS was determined using the universal testing machine (Instron) at 0.5 mm/min crosshead speed. Failure modes were recorded and a qualitative micromorphologic examination of different surface treatments was performed. The data were analyzed using the one-way analysis of variance (ANOVA) and Tukey honestly significant difference (HSD) tests.
RESULTS: The SBS of the control, sandblasting, silane, and sandblasting + silane groups were: 10.8 ± 1.5, 16.4 ± 3.4, 16.2 ± 2.5, and 19.1 ± 2.4 MPa respectively. According to the Tukey HSD test, only the mean SBS of the control group was significantly different from the other three groups. There was no significant difference between sandblasting, silane, and sandblasting + silane groups.
CONCLUSION: In this study, the three surface treatments used improved the bond strength of resin cement to Turkom-Cera disks.
CLINICAL SIGNIFICANCE: The surface treatments used in this study appeared to be suitable methods for the cementation of glass infiltrated all-ceramic restorations.

Matched MeSH terms: Aluminum Oxide/chemistry
Effect of root canal irrigation protocols on the dislocation resistance of mineral trioxide aggregate-based materials: A systematic review of laboratory studies

Neelakantan P, Ahmed HMA, Wong MCM, Matinlinna JP, Cheung GSP

Int Endod J, 2018 Aug;51(8):847-861.
PMID: 29377170 DOI: 10.1111/iej.12898

The aim of this systematic review was to address the question: Do different irrigating protocols have an impact on the dislocation resistance of mineral trioxide aggregate (MTA)-based materials? The review was performed using a well-defined search strategy in three databases (PubMed, Scopus, Web of Science) to include laboratory studies performed between January 1995 and May 2017, in accordance with PRISMA guidelines. Two reviewers analysed the papers, assessed the risk of bias and extracted data on teeth used, sample size, size of root canal preparation, type of MTA-based material, irrigants, canal filling method, storage method and duration, region of roots and the parameters of push-out testing (slice thickness, plunger dimensions and plunger loading direction), the main results and dislocation resistance values (in MPa). From 255 studies, 27 were included for full-text analysis. Eight papers that met the inclusion criteria were included in this review. There was a wide variation in dislocation resistance due to differences in irrigation sequence, time and concentration of irrigants, storage method and duration, and the parameters of push-out bond strength testing. A meta-analysis was not done but qualitative synthesis of the included studies was performed. No definitive conclusion could be drawn to evaluate the effect of irrigation protocols on dislocation resistance of MTA-based materials. Recommendations have been provided for standardized testing methods and reporting of future studies, so as to obtain clinically relevant information and to understand the effects of irrigating protocols on root canal sealers and their interactions with the dentine walls of root canals.

Matched MeSH terms: Aluminum Compounds/pharmacology*
Signal Enhancement Evaluation of Laser-Induced Breakdown Spectroscopy of Extracted Animal Fats Using Principal Component Analysis Approach

Hanasil NS, Raja Ibrahim RK, Duralim M, Sapingi HHJ, Mahdi MA

Appl Spectrosc, 2020 Dec;74(12):1452-1462.
PMID: 32166979 DOI: 10.1177/0003702820915532

In this work, principal component analysis (PCA) was utilized to analyze laser-induced breakdown spectroscopy (LIBS) signals of the extracted chicken fat, lamb fat, beef fat, and lard froze using two different freezing methods. The frozen samples were ablated using a neodymium-doped yttrium aluminum garnet (Nd:YAG) laser with a wavelength of 1064 nm, 170 mJ pulse energy, and 6 ns pulse duration to produce plasma on target surfaces. The samples were ablated using 30-60 shots of the laser beam at different spots. Stronger LIBS signals from the extracted chicken fat and lamb fat were obtained with liquid nitrogen (LN2) method. However, LIBS signals obtained from the freezer freezing method were found to be stronger for extracted beef fat and lard. The PCA was then used to visualize the LIBS spectra of extracted animal fats into a score plot. Data points of each extracted animal fat were divided into three groups representing LIBS spectra collected at the early, middle, and end part of the ablation process. The score plot revealed that the data points of the three groups of frozen extracted animal fats using the LN2 method were more closely clustered than those frozen in the freezer. Good discrimination with 97% of the variance was achieved between the extracted chicken fat, lamb fat, beef fat, and lard using the LN2 method in the three-dimensional score plot. LIBS signals of the extracted animal fats produced from the LN2 method were found to be more stable than those from the freezer method.

Matched MeSH terms: Aluminum/chemistry

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