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Comparison of the load at fracture of Turkom-Cera to Procera AllCeram and In-Ceram all-ceramic restorations

AL-Makramani BM, Razak AA, Abu-Hassan MI

J Prosthodont, 2009 Aug;18(6):484-8.
PMID: 19694015

PURPOSE: This study investigated the occlusal fracture resistance of Turkom-Cerafused alumina compared to Procera AllCeram and In-Ceram all-ceramic restorations.
MATERIALS AND METHODS: Sixmaster dies were duplicated from the prepared maxillary first premolar tooth using nonprecious metal alloy (Wiron 99). Ten copings of 0.6 mm thickness were fabricated from each type of ceramic, for a total of thirty copings. Two master dies were used for each group, and each of them was used to lute five copings. All groups were cemented with resin luting cement Panavia F according to manufacturer's instructions and received a static load of 5 kg during cementation. After 24 hours of distilled water storage at 37 degrees C, the copings were vertically compressed using a universal testing machine at a crosshead speed of 1 mm/min.
RESULTS: The results of the present study showed the following mean loads at fracture: Turkom-Cera (2184 +/- 164 N), In-Ceram (2042 +/- 200 N), and Procera AllCeram (1954 +/- 211 N). ANOVA and Scheffe's post hoc test showed that the mean load at fracture of Turkom-Cera was significantly different from Procera AllCeram (p < 0.05). Scheffe's post hoc test showed no significant difference between the mean load at fracture of Turkom-Cera and In-Ceram or between the mean load at fracture of In-Ceram and Procera AllCeram.
CONCLUSION: Because Turkom-Cera demonstrated equal to or higher loads at fracture than currently accepted all-ceramic materials, it would seem to be acceptable for fabrication of anterior and posterior ceramic crowns.

Matched MeSH terms: Aluminum Oxide
Fulltext Multivariate statistical analysis of antioxidants in dates (Phoenix dactylifera)

Abbas, F.M.A., Foroogh, B., Liong, M.T., Azhar, M.E.

International Food Research Journal, 2008;15(2):193-200.
MyJurnal

Four types of soft dates (SD), three types of semi-dried dates (SDD) and one type of dried dates (DD) were used in this study. The antioxidant activities were assessed using TEAC method (ABTS assay) and the ferric reducing/antioxidant power method (FRAP assay), while total phenolic content (TPC) and total flavonoid content (TFC) were measured using Folin-Ciocalteau and aluminum chloride colorimetric methods. Multivariate analysis of variance (MANOVA), discriminant analysis (DA) and principal component analysis (PCA) were used to analyze the data. MANOVA showed a strong significant difference between the eight types of dates. DA identified the relative contribution of each parameter in distinguishing the dates. DA also identified two functions responsible for discriminating the dates and showed the difference between different types of dates. The first function distinguished DD from other types of dates, whilst the second function discriminated SD and SDD, affording 100% correct assignation. PCA identified only one component responsible for explaining 98.85% of the total variance in antioxidant data. It is suggested that the TEAC method and the quantitative determination of TPC and TFC was suitable for differentiation of dates and quality control.

Matched MeSH terms: Aluminum Compounds
Fulltext Physico-mechanical properties and formaldehyde emission of rubberwood particleboard made with UF resin admixed with ammonium and aluminium-based hardeners

Abd Ghani Aizat, Paiman, Bawon, Lee, Seng Hua, Ashaari Zaidon

Pertanika Journal of Science & Technology, 2019;27(1):473-488.
MyJurnal

In this study, the effects of addition of ammonium and aluminium-based hardeners into
urea formaldehyde resin (UF) on the physico-mechanical properties and formaldehyde
emission of the rubberwood particleboard were investigated. Four types of hardeners,
namely ammonium chloride (AC), ammonium sulphate (AS), aluminium chloride (AlC)
and aluminium sulphate (AlS), were added into UF resin. The acidity, gelation time,
viscosity and free formaldehyde content of the UF/hardener mixtures were determined.
Particleboard made with the UF/hardener mixtures were tested for physico-mechanical
properties and formaldehyde emission. The pH values of the resin after addition of
aluminium-based hardeners were higher and resulted in higher viscosity and shorter
gelation time. Consequently, despite lower formaldehyde emission was recorded, the
physico-mechanical properties of the resulted particleboard were inferior compared to
that of ammonium-based hardeners. The best quality particleboard in terms of mechanical,
physical and formaldehyde emission were obtained from the particleboard made with AS,
followed by AC.

Matched MeSH terms: Aluminum; Aluminum Compounds
Fulltext Molecular Weight Cut-Off and Structural Analysis of Vacuum-Assisted Titania Membranes for Water Processing

Abd Jalil SN, Wang DK, Yacou C, Motuzas J, Smart S, Diniz da Costa JC

Materials (Basel), 2016 Nov 18;9(11).
PMID: 28774057 DOI: 10.3390/ma9110938

This work investigates the structural formation and analyses of titania membranes (TM) prepared using different vacuum exposure times for molecular weight (MW) cut-off performance and oil/water separation. Titania membranes were synthesized via a sol-gel method and coated on macroporous alumina tubes followed by exposure to a vacuum between 30 and 1200 s and then calcined at 400 °C. X-ray diffraction and nitrogen adsorption analyses showed that the crystallite size and particle size of titania increased as a function of vacuum time. All the TM membranes were mesoporous with an average pore diameter of ~3.6 nm with an anatase crystal morphology. Water, glucose, sucrose, and polyvinylpyrrolidone with 40 and 360 kDa (PVP-40 kDa and PVP-360 kDa) were used as feed solutions for MW cut-off and hexadecane solution for oil filtration investigation. The TM membranes were not able to separate glucose and sucrose, thus indicating the membrane pore sizes are larger than the kinetic diameter of sucrose of 0.9 nm, irrespective of vacuum exposure time. They also showed only moderate rejection (20%) of the smaller PVP-40 kDa, however, all the membranes were able to obtain an excellent rejection of near 100% for the larger PVP-360 kDa molecule. Furthermore, the TM membranes were tested for the separation of oil emulsions with a high concentration of oil (3000 ppm), reaching high oil rejections of more than 90% of oil. In general, the water fluxes increased with the vacuum exposure time indicating a pore structural tailoring effect. It is therefore proposed that a mechanism of pore size tailoring was formed by an interconnected network of Ti-O-Ti nanoparticles with inter-particle voids, which increased as TiO₂ nanoparticle size increased as a function of vacuum exposure time, and thus reduced the water transport resistance through the TM membranes.

Matched MeSH terms: Aluminum Oxide
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
Beberapa Hasil Penyiasatan Geofizik di Kawasan Bachok, Kelantan (Results on Geophysical Survey of Areas in Bachok, Kelantan)

Abd. Rahim Samsudin, Umar Hamzah, Abd. Ghani Rafek, Haryono

Sains Malaysiana, 1996;25.

The whole Bachok area is covered by alluvial deposit. The alluvium has three aquifers at depth of 0 - 5, 15 - 30 and 40 - 60 meters below surface. Preliminary geophysical surveys including seismic refraction, reflection and resistivity techniques have been carried out to investigate thickness and depth of the aquifers, depth of bedrock and the salinity of the underground water. Results show that the position of first aquifer has been well determined by seismic refraction technique. Whereas the details of deeper aquifers and the bedrock have been determined by seismic reflection techniques. Geoelectrical resistivity low obtained for the first aquifer suggest that it could be due to either salt water intrusion or the presence of marine clay.
Keseluruhan kawasan Bachok merupakan endapan aluvium. Endapan ini mempunyai tiga akuifer pada kedalaman 0 - 5 meter, 15 - 30 meter dan 40 - 60 meter. Kajian geofizik pada tahap awal yang merangkumi aspek seismos biasan, seismos pantulan dan kerintangan geoelektrik telah dilakukan untuk menyiasat ketebalan dan kedalaman akuifer, kedalaman batu dasar dan kemasinan air tanah. Hasil kajian menunjukkan bahawa teknik seismos biasan telah dapat menghasilkan maklumat mengenai kedudukan akuifer pertama. manakala teknik seismos pantulan menghasilkan maklumat terperinci mengenai akuifer kedua dan ketiga serta batu dasar. Nilai kerintangan geoelektrik rendah bagi akuifer pertama menunjukkan sama ada disebabkan oleh intrusi air masin atau kehadiran lempung samudera.

Matched MeSH terms: Aluminum Silicates
An integrated geophysical study of the quaternary basin at Olak Lempit – Banting Area, Selangor, Malaysia

Abdul Rahim Samsudin, Umar Hamzah, Zuraidah Ramli

Sains Malaysiana, 2007;36:159-163.

An integrated geophysical study was conducted to investigate the subsurface regional structure and the presence of a Quaternary sedimentary basin in the Olak Lempit - Banting area of Selangor, Malaysia. A regional gravity survey and the high resolution reflection seismic were employed to determine the thickness and areal distribution of the alluvial sedimentary basin as well as to investigate the depth and topography of the bedrock in the study area. The sedimentary basin hosts one of the most important coastal alluvial aquifer which was used to cater the shortage of domestic water supply during the worst water crisis that hit the state of Selangor in 1998. The surface geological map shows that in general 70% of the study area is covered by Quaternary deposits of Beruas, Gula and Simpang Formations which overlie the sedimentary bedrock of Kenny Hill Formation. The Beruas Formation consists of mainly clay, sandy clay and peat of Holocene fluviatile-estuarine deposits, whereas the Gula Formation represents Holocene marine to estuarine sediments which mostly consists of clay and minor sand. The Simpang Formation (Pleistocene) is a continental deposit comprising of gravel, sand, clay and silt. The underlying Kenny Hill Formation consists of a monotonous sequence of interbedded shales, mudstones and sandstones. The rock is Carbonaceous in age and it forms an undulating surface topography in the eastern part of the study area. A total of 121 gravity stations were established using a La Coste & Romberg gravity meter and the elevations of most of the stations were determined barometrically using Tiernan-Wallace altimeters. The high resolution seismic reflection using the common mid point (CMP) or roll along technique was carried out using a 24 channel signal enhancement seismograph and high frequency geophones. A total length of about 1.7 km stacked seismic section has been acquired in this survey and a nearby borehole data was used for interpretation. A relative Bouguer anomaly map shows an elongated zone of low gravity anomaly trending approximately NW-SE which is interpreted to be the deposition center of the Quaternary basin. The interpreted gravity profiles running across the central area of the study area show that the basin has thickness varies from tenth to several hundred meters with maximum depth to bedrock of about 275m. A gravity profile which passes through the eastern edge of the basin was modeled with depth to bedrock of about 178m below ground which agrees very well with those obtained from the interpreted seicmic section and borehole data. The stacked seismic section shows several high amplitude parallel to sub-parallel reflection overlying discontinuos and low reflection pattern. Reflections on the eastern part of the section is much shallower than the one observed on the western part which clearly indicates the presence of basinal structure with a total interpreted depth to bedrock of about 200 meters.

Matched MeSH terms: Aluminum Silicates
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
Fulltext Management of Perforating Idiopathic Internal Root Resorption

Abdullah D, Eziana Hussein F, Abd Ghani H

Iran Endod J, 2017;12(2):257-260.
PMID: 28512497 DOI: 10.22037/iej.2017.50

This case report describes the endodontic treatment of an idiopathic perforated internal root resorption. A 24-year-old male Malay patient presented with internal root resorption of two of his anterior teeth. The medical history was non-contributory and he had no history of traumatic injury or orthodontic treatment. Cone-beam computed tomography (CBCT) determined the nature, location and severity of the resorptive lesion. Non-surgical root canal treatment of tooth #22 and combined non-surgical and surgical approach for tooth #11 were carried out using mineral trioxide aggregate (MTA) as the filling material. The clinical and radiographic examination three years after completion of treatment revealed evidences of periapical healing. The appropriate diagnosis and the treatment of internal root resorption allowed good healing of these lesions and maintained the tooth in function for as long as possible.

Matched MeSH terms: Aluminum Compounds
Fulltext Potential Health Impacts of Bauxite Mining in Kuantan

Abdullah NH, Mohamed N, Sulaiman LH, Zakaria TA, Rahim DA

Malays J Med Sci, 2016 May;23(3):1-8.
PMID: 27418864

Bauxite mining is not known to most Malaysian except recently due to environmental pollution issues in Kuantan, Pahang. Potential impacts are expected to go beyond physical environment and physical illness if the situation is not controlled. Loss of economic potentials, and the presence of unpleasant red dust causing mental distress, anger and community outrage. More studies are needed to associate it with chronic physical illness. While evidences are vital for action, merely waiting for a disease to occur is a sign of failure in prevention. All responsible agencies should focus on a wider aspect of health determinants rather than merely on the occurrence of diseases to act and the need to emphasize on sustainable mining to ensure health of people is not compromised.

Matched MeSH terms: Aluminum Oxide
Fulltext Influence of alkylphosphonium modified montmorillonite to the tensile properties of PMMA composites

Abdullah, M.A.A., Mamat, M., Rusli, S.A., Kassim, A.A.

ASM Science Journal, 2018;11(101):96-104.
MyJurnal

Considering its excellent thermal stability, alkyl phosphonium surfactant: triisobutyl(methyl)phosphonium
(TIBMP) was used in this research as an intercalant for surface
modification of Na+-MMT via ion exchange process forming organomontmorillonite
(OMMT). The OMMT was then used as filler in poly(methyl methacrylate) (PMMA) via
melt intercalation technique. OMMT decomposed at a higher temperature than commercial
alkyammonium modified MMT. Exfoliated and intercalated types of nanocomposites
are obtained from PMMA/OMMTs at low and high content of OMMT loading, depending
on the space of those clay platelets had to disperse in PMMA. The ability of OMMT to
carry a certain load applied in PMMA matrix enhances the tensile strength in all composites.
TIBMP are compatible with PMMA matrix, and significantly improves the tensile
properties of PMMA composites.

Matched MeSH terms: Aluminum Silicates
Effect of mixing process parameters and suitability of backbone polymer for aluminum powder injection molding feedstock

Abdullahi A, Choudhury I, Azuddin M, Nahar N

Sains Malaysiana, 2017;46:477-483.

A suitable and cost-effective microfabrication technique for processing aluminum micropart is required, as the choice
of aluminum microparts for aerospace, electronics and automobile components is preferred over other metals due to its
excellent properties. Meanwhile, powder injection molding (PIM) is identified as an economical manufacturing technique
for processing ceramic and micro-metal powders into microparts and or components. Therefore, this study investigates
formulation and processing of aluminum PIM feedstock using a custom-made machine. The investigation is focused on
the effect of mixing process parameters (powder loading, rotor speed and mixing temperature) and the suitability of
the backbone polymer. The formulated PIM feedstock constituents are paraffin wax (PW), stearic acid (SA), high-density
polyethylene (HDPE)/ medium-density polyethylene (MDPE) alternatively and aluminum micro-metal powder. Taguchi
method is used for the design of experiments (DOEs) and analysis. In addition, response surface methodology (RSM) is
employed to develop empirical viscosity models. The optimum powder-binder mixing ratio of 58:42 vol. % with rotor
speed of 43 rpm were determined for preparing aluminum PIM feedstock using mini-lab mixer developed. The empirical
model developed for aluminum PIM feedstock viscosity shows a good fit with R2
values of 0.84 using HDPE and 0.96 for
MDPE binder system. This investigation demonstrates preparation and suitability of aluminum PIM feedstock using waxbased
binder system.

Matched MeSH terms: Aluminum
Fulltext Room temperature radiolytic synthesized Cu@CuAlO(2)-Al(2)O(3) nanoparticles

Abedini A, Saion E, Larki F, Zakaria A, Noroozi M, Soltani N

Int J Mol Sci, 2012;13(9):11941-53.
PMID: 23109893 DOI: 10.3390/ijms130911941

Colloidal Cu@CuAlO(2)-Al(2)O(3) bimetallic nanoparticles were prepared by a gamma irradiation method in an aqueous system in the presence of polyvinyl pyrrolidone (PVP) and isopropanol respectively as a colloidal stabilizer and scavenger of hydrogen and hydroxyl radicals. The gamma irradiation was carried out in a (60)Co gamma source chamber with different doses up to 120 kGy. The formation of Cu@CuAlO(2)-Al(2)O(3) nanoparticles was observed initially by the change in color of the colloidal samples from colorless to brown. Fourier transform infrared spectroscopy (FTIR) confirmed the presence of bonds between polymer chains and the metal surface at all radiation doses. Results of transmission electron microscopy (TEM), energy dispersive X-ray spectrometry (EDX), and X-ray diffraction (XRD) showed that Cu@CuAlO(2)-Al(2)O(3) nanoparticles are in a core-shell structure. By controlling the absorbed dose and precursor concentration, nanoclusters with different particle sizes were obtained. The average particle diameter increased with increased precursor concentration and decreased with increased dose. This is due to the competition between nucleation, growth, and aggregation processes in the formation of nanoclusters during irradiation.

Matched MeSH terms: Aluminum Compounds/chemical synthesis*; Aluminum Compounds/chemistry
Fulltext Open-gated pH sensor fabricated on an undoped-AlGaN/GaN HEMT structure

Abidin MS, Hashim AM, Sharifabad ME, Rahman SF, Sadoh T

Sensors (Basel), 2011;11(3):3067-77.
PMID: 22163786 DOI: 10.3390/s110303067

The sensing responses in aqueous solution of an open-gated pH sensor fabricated on an AlGaN/GaN high-electron-mobility-transistor (HEMT) structure are investigated. Under air-exposed ambient conditions, the open-gated undoped AlGaN/GaN HEMT only shows the presence of a linear current region. This seems to show that very low Fermi level pinning by surface states exists in the undoped AlGaN/GaN sample. In aqueous solution, typical current-voltage (I-V) characteristics with reasonably good gate controllability are observed, showing that the potential of the AlGaN surface at the open-gated area is effectively controlled via aqueous solution by the Ag/AgCl gate electrode. The open-gated undoped AlGaN/GaN HEMT structure is capable of distinguishing pH level in aqueous electrolytes and exhibits linear sensitivity, where high sensitivity of 1.9 mA/pH or 3.88 mA/mm/pH at drain-source voltage, V(DS) = 5 V is obtained. Due to the large leakage current where it increases with the negative gate voltage, Nernstian like sensitivity cannot be determined as commonly reported in the literature. This large leakage current may be caused by the technical factors rather than any characteristics of the devices. Surprisingly, although there are some imperfections in the device preparation and measurement, the fabricated devices work very well in distinguishing the pH levels. Suppression of current leakage by improving the device preparation is likely needed to improve the device performance. The fabricated device is expected to be suitable for pH sensing applications.

Matched MeSH terms: Aluminum Compounds/chemistry*
Co-synthesis and characterization of In2O3 and ZnO nanowires

Abrar Ismardi, Chang FD, Hamzah A, Bais B, Salleh M, Majlis B, et al.

Sains Malaysiana, 2012;41:459-463.

Co-synthesis of In2O3 and ZnO nanowires (NWs) were grown on silicon and alumina substrates using vapour transport deposition method. Their morphological structures showed that the NWs were rather aligned on silicon substrate and randomly oriented on alumina substrate. The formation of NWs on silicon substrate was found to be dominated by the growth of ZnO NWs while that on alumina substrate was dominated by the growth of In2O3 NWs. The In2O3 and ZnO NWs were highly crystalline and have wurtzite structure.

Matched MeSH terms: Aluminum Oxide
Fulltext Arsenic, zinc, and aluminium removal from gold mine wastewater effluents and accumulation by submerged aquatic plants (Cabomba piauhyensis, Egeria densa, and Hydrilla verticillata)

Abu Bakar AF, Yusoff I, Fatt NT, Othman F, Ashraf MA

Biomed Res Int, 2013;2013:890803.
PMID: 24102060 DOI: 10.1155/2013/890803

The potential of three submerged aquatic plant species (Cabomba piauhyensis, Egeria densa, and Hydrilla verticillata) to be used for As, Al, and Zn phytoremediation was tested. The plants were exposed for 14 days under hydroponic conditions to mine waste water effluents in order to assess the suitability of the aquatic plants to remediate elevated multi-metals concentrations in mine waste water. The results show that the E. densa and H. verticillata are able to accumulate high amount of arsenic (95.2%) and zinc (93.7%) and resulted in a decrease of arsenic and zinc in the ambient water. On the other hand, C. piauhyensis shows remarkable aluminium accumulation in plant biomass (83.8%) compared to the other tested plants. The ability of these plants to accumulate the studied metals and survive throughout the experiment demonstrates the potential of these plants to remediate metal enriched water especially for mine drainage effluent. Among the three tested aquatic plants, H. verticillata was found to be the most applicable (84.5%) and suitable plant species to phytoremediate elevated metals and metalloid in mine related waste water.

Matched MeSH terms: Aluminum/metabolism
Nano-silica embedded polydimethylsiloxane on interdigitated sensor as adhesive polymer for detecting lung cancer mutation

Abulaiti A, Salai A, Sun X, Yibulayin W, Gao Y, Gopinath SCB, et al.

Biotechnol Appl Biochem, 2021 Feb 12.
PMID: 33576539 DOI: 10.1002/bab.2122

Non-small cell lung cancer (NSCLC) incited by epidermal growth factor receptor (EGFR) mutation makes up ∼85% of lung cancer diagnosed and death cases worldwide. The presented study introduced an alternative approach in detecting EGFR mutation using nano-silica integrated with polydimethylsiloxane (PDMS) polymer on interdigitated electrode (IDE) sensor. A 400 μm gap-sized aluminum IDE was modified with nano-polymer layer, which was made up of silica nanoparticles and PDMS polymer. IDE and PDMS-coated IDE (PDMS/IDE) were imaged using electron microscopes that reveals its smooth and ideal sensor morphology. The nano-silica-integrated PDMS/IDE surface was immobilized with EGFR probe and target to specify the lung cancer detection. The sensor specificity was justified through the insignificant current readouts with one-base mismatch and noncomplementary targets. The sensitivity of nano-silica-integrated PDMS/IDE was examined with mutant target spiked in human serum, where the resulting current affirms the detection of EGFR mutation. Based on the slope of the calibration curve, the sensitivity of nano-silica-integrated PDMS/IDE was 2.24E-9 A M-1 . The sensor recognizes EGFR mutation lowest at 1 aM complementary mutant target; however, the detection limit obtained based on 3σ calculation is 10 aM with regression value of 0.97.

Matched MeSH terms: Aluminum
Distinguishing normal and aggregated alpha-synuclein interaction on gold nanorod incorporated zinc oxide nanocomposite by electrochemical technique

Adam H, Gopinath SCB, Arshad MKM, Parmin NA, Hashim U

Int J Biol Macromol, 2021 Feb 28;171:217-224.
PMID: 33418041 DOI: 10.1016/j.ijbiomac.2021.01.014

Misfolding and accumulation of the protein alpha synuclein in the brain cells characterize Parkinson's disease (PD). Electrochemical based aluminum interdigitated electrodes (ALIDEs) was fabricated by using conventional photolithography method and modified the surfaces with zinc oxide and gold nanorod by using spin coating method for the analysis of PD protein biomarker. The device surface modified with gold nanorod of 25 nm diameter was used. The bare devices and the surface modified devices were characterized by Scanning Electron Microscope, 3D-Profilometer, Atomic Force Microscope and high-power microscope. The above measurement was also performed to measure the interaction of antibody with aggregated alpha-synuclein for normal, aggregated and aggregated alpha synuclein in human serum and distinguished against 3 control proteins (PARK1, DJ-1 and Factor IX). The detection limit for normal alpha synuclein was 1 f. with the sensitivity of 1 f. on a linear regression (R2 = 0.9759). The detection limit for aggregated alpha synuclein was 10 aM with the sensitivity of 1 aM on a linear regression (R2 = 0.9797). Also, the detection limit of aggregated alpha synuclein in serum was 10 aM with the sensitivity of 1 aM on a linear regression (R2 = 0.9739). These results however indicate that, serum has only minimal amount of alpha synuclein.

Matched MeSH terms: Aluminum
Fulltext Role of Phase-Dependent Dielectric Properties of Alumina Nanoparticles in Electromagnetic-Assisted Enhanced Oil Recovery

Adil M, Lee KC, Zaid HM, Manaka T

Nanomaterials (Basel), 2020 Oct 06;10(10).
PMID: 33036153 DOI: 10.3390/nano10101975

The utilization of metal-oxide nanoparticles in enhanced oil recovery (EOR) has generated considerable research interest to increase the oil recovery. Among these nanoparticles, alumina nanoparticles (Al2O3-NPs) have proved promising in improving the oil recovery mechanism due to their prominent thermal properties. However, more significantly, these nanoparticles, coupled with electromagnetic (EM) waves, can be polarized to reduce water/oil mobility ratio and create disturbances at the oil/nanofluid interface, so that oil can be released from the reservoir rock surfaces and travelled easily to the production well. Moreover, alumina exists in various transition phases (γ, δ, θ, κ, β, η, χ), providing not only different sizes and morphologies but phase-dependent dielectric behavior at the applied EM frequencies. In this research, the oil recovery mechanism under EM fields of varying frequencies was investigated, which involved parameters such as mobility ratio, interfacial tension (IFT) and wettability. The displacement tests were conducted in water-wet sandpacks at 95 °C, by employing crude oil from Tapis. Alumina nanofluids (Al2O3-NFs) of four different phases (α, κ, θ and γ) and particle sizes (25-94.3 nm) were prepared by dispersing 0.01 wt. % NPs in brine (3 wt. % NaCl) together with SDBS as a dispersant. Three sequential injection scenarios were performed in each flooding scheme: (i) preflushes brine as a secondary flooding, (ii) conventional nano/EM-assisted nanofluid flooding, and (iii) postflushes brine to flush NPs. Compared to conventional nanofluid flooding (3.03-11.46% original oil in place/OOIP) as incremental oil recovery, EM-assisted nanofluid flooding provided an increase in oil recovery by approximately 4.12-12.90% of OOIP for different phases of alumina. It was established from these results that the recovery from EM-assisted nanofluid flooding is itself dependent on frequency, which is associated with good dielectric behavior of NPs to formulate the oil recovery mechanism including (i) mobility ratio improvement due to an electrorheological (ER) effect, (ii) interfacial disturbances by the oil droplet deformation, and (iii) wettability alteration by increased surface-free energy.

Matched MeSH terms: Aluminum Oxide
Preparation, characterisation and viability of encapsulated Trichoderma harzianum UPM40 in alginate-montmorillonite clay

Adzmi F, Meon S, Musa MH, Yusuf NA

J Microencapsul, 2012;29(3):205-10.
PMID: 22309479 DOI: 10.3109/02652048.2012.659286

Microencapsulation is a process by which tiny parcels of an active ingredient are packaged within a second material for the purpose of shielding the active ingredient from the surrounding environment. This study aims to determine the ability of the microencapsulation technique to improve the viability of Trichoderma harzianum UPM40 originally isolated from healthy groundnut roots as effective biological control agents (BCAs). Alginate was used as the carrier for controlled release, and montmorillonite clay (MMT) served as the filler. The encapsulated Ca-alginate-MMT beads were characterised using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The FTIR results showed the interaction between the functional groups of alginate and MMT in the Ca-alginate-MMT beads. Peaks at 1595, 1420 and 1020 cm(-1) characterised alginate, and peaks at 1028 and 453 cm(-1) characterised MMT; both sets of peaks appeared in the Ca-alginate-MMT FTIR spectrum. The TGA analysis showed an improvement in the thermal stability of the Ca-alginate-MMT beads compared with the alginate beads alone. SEM analysis revealed a homogeneous distribution of the MMT particles throughout the alginate matrix. T. harzianum UPM40 was successfully encapsulated in the Ca-alginate-MMT beads. Storage analysis of the encapsulated T. harzianum UPM40 showed that the low storage temperature of 5°C resulted in significantly (p

Matched MeSH terms: Aluminum Silicates

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