87 results on '"Althobaiti, M."'
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2. Exploring the structural and optical properties of Cu1−xNixO/ZnO nanostructured heterojunctions for optoelectronic studies
- Author
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Badawi, Ali, Althobaiti, M. G., Alotaibi, Abdullah A., and Alharthi, Sami S.
- Published
- 2024
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3. Structure, Dielectric Permittivity, and AC Conductivity of Cobalt and Lanthanum Doped TiO2 Composites
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Abdel-Baset, T., Alotaibi, Abdullah A., Bashal, Ali H., and Althobaiti, M. G.
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- 2023
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4. Facile synthesis of Cu0.9Co0.1−xSnxO nanostructures and their structural, optical and dielectric properties for optoelectronic applications
- Author
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Althobaiti, M. G., Alotaibi, Abdullah A., Alharthi, Sami S., and Badawi, Ali
- Published
- 2023
- Full Text
- View/download PDF
5. Tailoring the structural and optical characteristics of hematite (α-Fe2O3) nanostructures by barium/aluminum dual doping for eco-friendly applications
- Author
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Badawi, Ali, Alharthi, Sami S., Alotaibi, Abdullah A., and Althobaiti, M. G.
- Published
- 2023
- Full Text
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6. A Study on Dielectric Permittivity, Structure, and AC Conductivity of Zinc and Copper Doped Bentonite Composites
- Author
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Abou Elfadl, A., Bashal, Ali H., and Althobaiti, M. G.
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- 2022
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7. Impact of silver/copper dual-doping on the structure, linear and non-linear optical performance of ZnO thin films
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Althobaiti, M. G., Alharthi, Sami S., Alharbi, Abdulaziz N., and Badawi, Ali
- Published
- 2022
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8. Exploring the structural and optical properties of Cu1−xNixO/ZnO nanostructured heterojunctions for optoelectronic studies.
- Author
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Badawi, Ali, Althobaiti, M. G., Alotaibi, Abdullah A., and Alharthi, Sami S.
- Subjects
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OPTICAL properties , *HETEROJUNCTIONS , *OPTICAL constants , *OPTICAL susceptibility , *OPTOELECTRONICS , *ZINC oxide films , *SCANNING electron microscopes , *PERMITTIVITY - Abstract
The current work aims to explore the structural and optical properties of Cu1−xNixO/ZnO nanostructured heterojunctions for optoelectronic applications. ZnO nanostructures and different Cu1−xNixO/ZnO (x; 0, 0.05, 0.10, 0.15 and 0.20) nanostructured heterojunctions were prepared by spray pyrolysis procedure on glass substrates. The surfaces morphology of the samples was examined by a scanning electron microscope (SEM). The energy dispersive X-ray (EDX) microscope was utilized to examine the elemental analysis. The XRD measurements show that ZnO nanostructures possess a hexagonal wurtzite structure, while Cu1−xNixO nanostructures possess monoclinic structures. The FT-IR spectroscopy was performed to explore the chemical bondings and functional groups. The UV–visible-NIR spectrophotometer was used to investigate the optical properties. The optical constants (refractive index, extinction coefficient, dielectric constants, optical conductivity) of the prepared samples have been investigated. The first-order linear optical susceptibility, third-order optical susceptibility and nonlinear refractive index are also studied. The obtained results show that the optical parameters of Cu1−xNixO/ZnO heterojunction could be tuned through controlling the Ni content. These novel findings nominate Cu1−xNixO/ZnO nanostructured heterojunctions for a plenty of optical, photocatalytic and optoelectronic applications. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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9. Effect of zinc doping on the structure and optical properties of iron oxide nanostructured films prepared by spray pyrolysis technique
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Badawi, Ali, Althobaiti, M. G., Alharthi, Sami S., Alharbi, Abdulaziz N., Alkathiri, Ali A., and Alomairy, Sultan E.
- Published
- 2022
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10. Investigation of the mechanical and electrical properties of SnS filled PVP/PVA polymeric composite blends
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Badawi, Ali, Alharthi, Sami S., Alotaibi, Abdullah A., and Althobaiti, M. G.
- Published
- 2021
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11. Structure investigation and optical bandgap tuning of La-doped CuO nanostructured films prepared by spray pyrolysis technique
- Author
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Badawi, Ali, Alharthi, Sami S., Althobaiti, M. G., Alharbi, Abdulaziz N., Assaedi, Hasan, Alkhammash, Hend I., and Al-Hosiny, N.
- Published
- 2021
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12. Effect of carbon quantum dots on the optical and electrical properties of polyvinylidene fluoride polymer for optoelectronic applications
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Badawi, Ali, Alharthi, Sami S., Mostafa, Nasser Y., Althobaiti, M. G., and Altalhi, Tariq
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- 2019
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13. Role of Cu/ZnO Nanostructures Doping on the Optical Behavior of Polyvinyl Alcohol/Polyvinyl Pyrrolidone/Graphene Composites for Optoelectronic Applications.
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Althobaiti, M. G. and Badawi, Ali
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COPPER , *POLYVINYL alcohol , *POLYMERIC nanocomposites , *GRAPHENE , *NANOSTRUCTURES - Abstract
The linear/non-linear optical and dielectric performance of PVA/PVP/graphene composites were enhanced by doping with Cu/ZnO (ZCO) nanoparticles (NPs) for optoelectronic applications. Bare and ZCO polymeric nanocomposites (PNCs) blends were fabricated by the casting method. The structure of the synthesized ZCO NPs and ZCO PNCs was studied by X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectroscopy techniques. The optical performance was characterized based on UV-visible-NIR data. The XRD investigations revealed the wurtzite structure of the ZCO NPs with a crystallite size of 17.8 nm. The FT-IR investigations confirmed the integration of ZCO NPs with the host blend's structure. The optical analysis exposed that the direct and indirect band gap of the host blend decreased from 5.20 and 4.94 to 4.36 and 4.29 eV for 10 wt% of ZCO PNCs. The Urbach energy rose from 0.62 to 1.28 eV for 10 wt% of ZCO PNCs. The refractive index grew from 1.29 (bare blend) to 1.82 for 10 wt% of ZCO PNC at hν = 2.0 eV. In addition, a great enhancement in the non-linear optical constants was achieved via ZCO doping. The third-order non-linear susceptibility, χ(3), increased from 1.30 × 10−13 esu (bare) to 9.23 × 10−11 esu for 10 wt% of ZCO PNC at hν = 5.0 eV. We suggest these valuable achievements in the optical behavior of PVA/PVP/graphene blend by ZCO doping nominate it for applications in optical device improvement. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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14. Hafnia and alumina on sulphur passivated germanium
- Author
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Althobaiti, M., Mather, S., Sedghi, N., Dhanak, V.R., Mitrovic, I.Z., Hall, S., and Chalker, P.R.
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- 2015
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15. Facile synthesis of Cu0.9Co0.1−xSnxO nanostructures and their structural, optical and dielectric properties for optoelectronic applications.
- Author
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Althobaiti, M. G., Alotaibi, Abdullah A., Alharthi, Sami S., and Badawi, Ali
- Abstract
The structural, linear/nonlinear optical and dielectric properties of Cu
0.9 Co0.1−x Snx O (CCTO) nanostructured films have been studied for optoelectronic applications. CCTO films with different compositions were equipped by spray pyrolysis procedure. The structure, crystallographic and morphological properties were examined by FT-IR, XRD and SEM procedures. The FT-IR measurements expose clear alterations in the structures of CCTO films due to composition variation. XRD results reveal that all CCTO nanostructured films have the monoclinic structure with crystallite size changes from 24.2 to 18.7 nm. SEM micrographs show that CCTO films possess high porous surfaces. UV–Vis. NIR measurements are used to investigate the linear/nonlinear optical parameters of prepared films. The UV–Vis–NIR analysis reveals that all films have absorption coefficient values with orders range from 104 to 105 cm−1 . The energy band gap Eg of CCTO films ranges from 1.24 to 1.14 eV upon varying x value. These findings are discussed on the basis of Moss Burstein effect and created defects. Clear impact of the composition (x) on the linear optical properties of CCTO is noticed. For example, the real dielectric constant εr varies from 23.97 to 9.74 via controlling the content composition. Moreover, the linear and nonlinear susceptibility and refractive index of CCTO films have been examined. This study proposes CCTO nanostructured films of environmentally friendly applications as photocatalysts, solar cells, optoelectronics and ultra-fast optical switching devices. [ABSTRACT FROM AUTHOR]- Published
- 2023
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16. Tailoring the structural and optical characteristics of hematite (α-Fe2O3) nanostructures by barium/aluminum dual doping for eco-friendly applications.
- Author
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Badawi, Ali, Alharthi, Sami S., Alotaibi, Abdullah A., and Althobaiti, M. G.
- Subjects
HEMATITE ,BARIUM ,PERMITTIVITY ,OPTICAL conductivity ,REFRACTIVE index ,OPTICAL constants ,MOSSBAUER spectroscopy - Abstract
In the current work, the structural and optical characteristics of hematite (α-Fe
2 O3 ) have been tailored by individual and dual doping of Ba and Al for photocatalytic and eco-friendly applications. The doped and undoped hematite nanostructures were synthesized onto quartz substrates via the spray pyrolysis route. The surfaces' morphology, vibrational bands and structural properties were investigated based on FE-SEM, FT–IR and XRD measurements, respectively. The XRD analysis reveals that all samples have a rhombohedral hematite structure. The crystallite size varies from 20.8 nm (undoped hematite) to 27.6 nm (Ba-doped hematite), 24.3 nm (Al-doped hematite) and 22.8 nm (Ba/Al dual doped hematite). The optical transmittance, absorbance and reflectance spectra were recorded by a UV–Vis–NIR spectrophotometer. The UV–Vis–NIR analysis shows that Ba/Al dual doped hematite film possesses an optimal absorption amount in the region where the wavelength λ > 561 nm. The direct energy band gap (Eg ) changes from 2.30 eV (undoped hematite) to 2.42 eV nm (Ba-doped hematite), 2.18 eV nm (Al-doped hematite) and 2.22 eV nm (Ba/Al dual doped hematite). Clear enhancement in the refractive index (n), dielectric constants and optical conductivity of the hematite NPs is attained via individual or dual doping of Ba and Al elements. For example, at λ = 550 nm, n of the undoped hematite increases from 1.88 to 1.91 (Ba-doped hematite), 2.07 (Al-doped hematite) and 1.97 (Ba/Al dual doped hematite). These novel results nominate the individual Ba, Al and Ba/Al dual doped hematite NPs for applications in photocatalysts and eco-friendly devices. [ABSTRACT FROM AUTHOR]- Published
- 2023
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17. Interface engineering of Ge using thulium oxide: Band line-up study
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Mitrovic, I.Z., Althobaiti, M., Weerakkody, A.D., Sedghi, N., Hall, S., Dhanak, V.R., Chalker, P.R., Henkel, C., Dentoni Litta, E., Hellström, P.-E., and Östling, M.
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- 2013
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18. Low EOT GeO2/Al2O3/HfO2 on Ge substrate using ultrathin Al deposition
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Mather, S., Sedghi, N., Althobaiti, M., Mitrovic, I.Z., Dhanak, V., Chalker, P.R., and Hall, S.
- Published
- 2013
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19. Structure, Dielectric Permittivity, and AC Conductivity of Cobalt and Lanthanum Doped TiO2 Composites.
- Author
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Abdel-Baset, T., Alotaibi, Abdullah A., Bashal, Ali H., and Althobaiti, M. G.
- Subjects
LANTHANUM ,DIELECTRIC properties ,DIELECTRICS ,ACTIVATION energy ,COBALT - Abstract
Lanthanum doped titanium dioxide (La/TiO
2 ) was synthesized by a lengthy wet impregnation method with cobalt (Co/TiO2 ). The prepared composites were characterized by X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), and scanning electron microscopy (SEM). The XRD spectrum of TiO2 shows that the transition dopants are well dispersed within the TiO2 matrix. The SEM images show no noticeable morphological differences between the TiO2 , La/TiO2, and Co/TiO2 composites. The dielectric properties and electrical of TiO2 , La/TiO2, and Co/TiO2 were investigated within temperature and frequency of 25–120 °C and 100 Hz to 0.3 MHz, respectively. It was noted that the dielectric constant decreases with increasing temperature. TiO2 dielectric permittivity and electrical conductivity increased as a result of doping. In addition, the activation energy values for all samples were evaluated. By increasing frequency, activation energy values decreased and this decrease intensified when the Co ions are the substituents in the TiO2 matrix. Otherwise, the values of activation energy are constant for La-dopedTiO2. [ABSTRACT FROM AUTHOR]- Published
- 2023
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20. Exploring the functional properties of PVP/PVA blend incorporated with non-stoichiometric SnS for optoelectronic devices.
- Author
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Alharthi, Sami S., Althobaiti, M. G., Alkathiri, Ali A., Ali, Essam E., and Badawi, Ali
- Abstract
The functional properties of polyvinyl pyrrolidone/polyvinyl alcohol (PVP/PVA) blend incorporated with non-stoichiometric tin sulphide (SnS) have been explored for optoelectronic devices. PVP/PVA blend incorporated with non-stoichiometric Sn/S ratios (1:0.8–1:1.2) of 1.0 wt.% SnS were prepared by casting method. The effect of the non-stoichiometric Sn/S ratio of SnS on the structure, optical and photoluminescent (PL) properties of the composite was examined by Fourier transform infrared, UV-visible-NIR and photoluminescence spectrophotometers. The optical band gap energy decreases, while Urbach energy increases via SnS incorporation. The lattice dielectric constant is improved about three times, while the free carriers' concentration to the effective mass is enhanced by one order of magnitude due to SnS1.2 incorporating. PL measurements reveal that PVP/PVA blends incorporated with SnS could emit spectra in the visible region. Designing the optical and photoluminescent properties of the PVP/PVA blend reveal their role in advanced optoelectronic devices. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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21. Atomic-layer deposited thulium oxide as a passivation layer on germanium.
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Mitrovic, I. Z., Hall, S., Althobaiti, M., Hesp, D., Dhanak, V. R., Santoni, A., Weerakkody, A. D., Sedghi, N., Chalker, P. R., Henkel, C., Dentoni Litta, E., Hellström, P.-E., Östling, M., Tan, H., and Schamm-Chardon, S.
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THULIUM ,X-ray photoelectron spectroscopy ,ELLIPSOMETRY ,TRANSMISSION electron microscopy ,ELECTRONS - Abstract
A comprehensive study of atomic-layer deposited thulium oxide (Tm
2 O3 ) on germanium has been conducted using x-ray photoelectron spectroscopy (XPS), vacuum ultra-violet variable angle spectroscopic ellipsometry, high-resolution transmission electron microscopy (HRTEM), and electron energy-loss spectroscopy. The valence band offset is found to be 3.0±60.2 eV for Tm2 O3 /p-Ge from the Tm 4d centroid and Ge 3p3/2 charge-corrected XPS core-level spectra taken at different sputtering times of a single bulk thulium oxide sample. A negligible downward band bending of ~0.12 eV is observed during progressive differential charging of Tm 4d peaks. The optical band gap is estimated from the absorption edge and found to be 5.77 eV with an apparent Urbach tail signifying band gap tailing at ~5.3 eV. The latter has been correlated to HRTEM and electron diffraction results corroborating the polycrystalline nature of the Tm2 O3 films. The Tm2 O3 /Ge interface is found to be rather atomically abrupt with sub-nanometer thickness. In addition, the band line-up of reference GeO2 /n-Ge stacks obtained by thermal oxidation has been discussed and derived. The observed low reactivity of thulium oxide on germanium as well as the high effective barriers for holes (~3 eV) and electrons (~2 eV) identify Tm2 O3 as a strong contender for interfacial layer engineering in future generations of scaled high-κ gate stacks on Ge. [ABSTRACT FROM AUTHOR]- Published
- 2015
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22. Synthesis, Crystal Structure, Hirshfeld Surface, and Physicochemical Characterization of New Salt Bis(2-ethyl-6-methylanilinium)tetrachloromercurate (II) [C9H14N]2HgCl4.
- Author
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Ayari, Chaima, Althobaiti, M. G., Alotaibi, Abdullah A., Almarri, Abdulhadi. H., Ferretti, Valeria, Ben Nasr, Cherif, and Mrad, Mohamed Habib
- Subjects
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CRYSTAL structure , *THERMOGRAVIMETRY , *DIFFERENTIAL thermal analysis , *SURFACE analysis , *SCANNING electron microscopy - Abstract
In this paper, a new organic salt bis(2-ethyl-6-methylanilinium)tetrachloromercurate (II)) has been synthesized, characterized, and studied theoretically using DFT. The synthesized compound was found to crystallize in the monoclinic system with space group P21/c with the following unit cell parameters a = 23.1696(2), b = 25.7951 (6), c = 7.5980 (4) Å, β = 96.5790 (11)°, and Z = 8. Its atomic arrangement can be described asmutually alternating organic and inorganic entities in the (ab) plane. The cohesion is achieved through N-H...Cl hydrogen bonds and π...π stacking interacting neighboring aromatic cations. The PXRD was carried out. The intermolecular interactions in the crystal packing were investigated using Hirshfeld surface analysis. Its associated 2D fingerprint plots revealed their contribution quantitatively. High-resolution images of the surface were obtained by the SEM technique, and the EDX spectrum assured the existence of all nonhydrogen atoms. The infrared spectrum was used to gain more information about vibrational modes. Analysis of thermal differential and gravimetric (TGA/DTA) shows two-phase transitions observed at 362 and 394 K. AC conductivity measurements were performed to confirm these two-phase transitions. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
23. Synthesis, Crystal Structure, Hirshfeld Surface, and Physicochemical Characterization of New Salt Bis(2-ethyl-6-methylanilinium)tetrachloromercurate (II) [C9H14N]2HgCl4.
- Author
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Ayari, Chaima, Althobaiti, M. G., Alotaibi, Abdullah A., Almarri, Abdulhadi. H., Ferretti, Valeria, Ben Nasr, Cherif, and Mrad, Mohamed Habib
- Subjects
CRYSTAL structure ,THERMOGRAVIMETRY ,DIFFERENTIAL thermal analysis ,SURFACE analysis ,SCANNING electron microscopy - Abstract
In this paper, a new organic salt bis(2-ethyl-6-methylanilinium)tetrachloromercurate (II)) has been synthesized, characterized, and studied theoretically using DFT. The synthesized compound was found to crystallize in the monoclinic system with space group P21/c with the following unit cell parameters a = 23.1696(2), b = 25.7951 (6), c = 7.5980 (4) Å, β = 96.5790 (11)°, and Z = 8. Its atomic arrangement can be described asmutually alternating organic and inorganic entities in the (ab) plane. The cohesion is achieved through N-H...Cl hydrogen bonds and π...π stacking interacting neighboring aromatic cations. The PXRD was carried out. The intermolecular interactions in the crystal packing were investigated using Hirshfeld surface analysis. Its associated 2D fingerprint plots revealed their contribution quantitatively. High-resolution images of the surface were obtained by the SEM technique, and the EDX spectrum assured the existence of all nonhydrogen atoms. The infrared spectrum was used to gain more information about vibrational modes. Analysis of thermal differential and gravimetric (TGA/DTA) shows two-phase transitions observed at 362 and 394 K. AC conductivity measurements were performed to confirm these two-phase transitions. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
24. Ge interface engineering using ultra-thin La2O3 and Y2O3 films: A study into the effect of deposition temperature.
- Author
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Mitrovic, I. Z., Althobaiti, M., Weerakkody, A. D., Dhanak, V. R., Linhart, W. M., Veal, T. D., Sedghi, N., Hall, S., Chalker, P. R., Tsoutsou, D., and Dimoulas, A.
- Subjects
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THIN films spectra , *PULSED laser deposition , *THIN films , *OPTICAL properties , *COMPLEMENTARY metal oxide semiconductors , *GAS absorption & adsorption - Abstract
A study into the optimal deposition temperature for ultra-thin La2O3 and Y2O3/Ge gate stacks has been conducted in this paper with the aim to tailor the interfacial layer for effective passivation of the Ge interface. A detailed comparison between the two lanthanide oxides ( La2O3 and Y2O3) in terms of band line-up, interfacial features, and reactivity to Ge using medium energy ion scattering, vacuum ultra-violet variable angle spectroscopic ellipsometry (VUV-VASE), X-ray photoelectron spectroscopy, and X-ray diffraction is shown. La2O3 has been found to be more reactive to Ge than Y2O3, forming LaGeOx and a Ge sub-oxide at the interface for all deposition temperature studied, in the range from 44 °C to 400°C. In contrast, Y2O3/Ge deposited at 400 °C allows for an ultra-thin GeO2 layer at the interface, which can be eliminated during annealing at temperatures higher than 525 °C leaving a pristine YGeOx/Ge interface. The Y2O3/Ge gate stack deposited at lower temperature shows a sub-band gap absorption feature fitted to an Urbach tail of energy 1.1 eV. The latter correlates to a sub-stoichiometric germanium oxide layer at the interface. The optical band gap for the Y2O3/Ge stacks has been estimated to be 5.7±0.1 eV from Tauc-Lorentz modelling of VUV-VASE experimental data. For the optimal deposition temperature (400 °C), the Y2O3/Ge stack exhibits a higher conduction band offset (∼2.3 eV) than the La2O3/Ge °2 eV), has a larger band gap (by about 0.3 eV), a germanium sub-oxide free interface, and leakage current (°10°7 A/cm2 at 1V) five orders of magnitude lower than the respective La2O3/Ge stack. Our study strongly points to the superiority of the Y2O3/Ge system for germanium interface engineering to achieve high performance Ge Complementary Metal Oxide Semiconductor technology. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
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25. Interface Engineering Routes for a Future CMOS Ge-based Technology
- Author
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Mitrovic, IZ, Althobaiti, M, Weerakkody, AD, Sedghi, N, Hall, S, Dhanak, VR, Mather, S, Chalker, PR, Tsoutsou, D, Dimoulas, A, Henkel, C, Litta, E Dentoni, Hellstrom, P-E, and Ostling, M
- Published
- 2014
26. Band alignments at Ga2O3 heterojunction interfaces with Si and Ge.
- Author
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Gibbon, J. T., Jones, L., Roberts, J. W., Althobaiti, M., Chalker, P. R., Mitrovic, Ivona Z., and Dhanak, V. R.
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GALLIUM compounds ,ATOMIC layer deposition ,PHOTOELECTRON spectroscopy ,HETEROJUNCTIONS ,VALENCE bands - Abstract
Amorphous Ga
2 O3 thin films were deposited on p-type (111) and (100) surfaces of silicon and (100) germanium by atomic layer deposition (ALD). X-ray photoelectron spectroscopy (XPS) was used to investigate the band alignments at the interfaces using the Kraut Method. The valence band offsets were determined to be 3.49± 0.08 eV and 3.47± 0.08 eV with Si(111) and Si(100) respectively and 3.51eV± 0.08 eV with Ge(100). Inverse photoemission spectroscopy (IPES) was used to investigate the conduction band of a thick Ga2 O3 film and the band gap of the film was determined to be 4.63±0.14 eV. The conduction band offsets were found to be 0.03 eV and 0.05eV with Si(111) and Si(100) respectively, and 0.45eV with Ge(100). The results indicate that the heterojunctions of Ga2 O3 with Si(100), Si(111) and Ge(100) are all type I heterojunctions. [ABSTRACT FROM AUTHOR]- Published
- 2018
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27. Band alignment of Ta2O5 on sulphur passivated Germanium by X-ray photoelectron spectroscopy.
- Author
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Althobaiti, M. G., Stoner, J., Dhanak, V. R., Potter, R. J., and Mitrovic, I. Z.
- Published
- 2015
- Full Text
- View/download PDF
28. The Coordination Behavior of Two New Complexes, [(C 7 H 10 NO 2)CdCl 3 ] n (I) and [(C 7 H 9 NO 2)CuCl 2 ] (II), Based on 2,6-Dimethanolpyridine; Elaboration of the Structure and Hirshfeld Surface, Optical, Spectroscopic and Thermal Analysis.
- Author
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Hermi, Sabrine, Alotaibi, Abdullah A., Alswieleh, Abdullah M., Alotaibi, Khalid M., Althobaiti, M. G., Jelsch, Christian, Wenger, Emmanuel, Nasr, Cherif Ben, and Mrad, Mohamed Habib
- Subjects
THERMAL analysis ,SURFACE structure ,OPTICAL spectroscopy ,LIGHT absorption ,HYDROXYL group - Abstract
Two novel complexes, [(C
7 H10 NO2 )CdCl3 ]n (I) and [(C7 H9 NO2 )CuCl2 ],havebeen synthesized and characterized. Single crystal X-ray diffraction revealed that in compound (I), 2,6-dimethanol pyridinium acts as a monodentate ligand through the O atom of the hydroxyl group. Contrarily, the 2,6-dimethanol pyridine ligand interacts tridentately with the Cu(II) ion via the nitrogen atoms and the two oxygen (O, O') atoms of the two hydroxyl groups. The structure's intermolecular interactions were studied using contact enrichment ratios and Hirshfeld surfaces. Following metal coordination, numerous hydrogen connections between entities and parallel displacement stacking interactions between pyridine rings dictate the crystal packing of both compounds. The aromatic cycles generate layers in the crystal for both substances. Powder XRD measurements confirmed the crystalline sample phase purity. SEM confirmed the surface homogeneity, whereas EDX semi-quantitative analysis corroborated the composition. IR spectroscopy identified vibrational absorption bands, while optical UV-visible absorption spectroscopy investigated optical properties. The thermal stability of the two materials was tested using TG-DTA. [ABSTRACT FROM AUTHOR]- Published
- 2022
- Full Text
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29. Low EOT GeO2/Al2O3/HfO2 on Ge substrate using ultrathin Al deposition.
- Author
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Mather, S., Sedghi, N., Althobaiti, M., Mitrovic, I.Z., Dhanak, V., Chalker, P.R., and Hall, S.
- Subjects
- *
GERMANIUM compounds , *ALUMINUM oxide , *HAFNIUM oxide , *LOGIC circuits , *METAL oxide semiconductors , *STRAY currents - Abstract
Highlights: [•] Ge gate MOS devices were investigated due to its applicability to sub 16nm node pMOST technology. [•] GeO2/Al2O3/HfO2 gate stacks were grown by a combined MBE and ALD technique. [•] Devices were characterised by various physical and electrical methods. [•] Devices were found to have low EOT and leakage currents and have small hysteresis. [Copyright &y& Elsevier]
- Published
- 2013
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30. Recent progress on smart lower prosthetic limbs: a comprehensive review on using EEG and fNIRS devices in rehabilitation.
- Author
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AlQahtani NJ, Al-Naib I, and Althobaiti M
- Abstract
The global rise in lower limb amputation cases necessitates advancements in prosthetic limb technology to enhance the quality of life for affected patients. This review paper explores recent advancements in the integration of EEG and fNIRS modalities for smart lower prosthetic limbs for rehabilitation applications. The paper synthesizes current research progress, focusing on the synergy between brain-computer interfaces and neuroimaging technologies to enhance the functionality and user experience of lower limb prosthetics. The review discusses the potential of EEG and fNIRS in decoding neural signals, enabling more intuitive and responsive control of prosthetic devices. Additionally, the paper highlights the challenges, innovations, and prospects associated with the incorporation of these neurotechnologies in the field of rehabilitation. The insights provided in this review contribute to a deeper understanding of the evolving landscape of smart lower prosthetic limbs and pave the way for more effective and user-friendly solutions in the realm of neurorehabilitation., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 AlQahtani, Al-Naib and Althobaiti.)
- Published
- 2024
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31. The risk of tuberculosis infection in Saudi patients receiving adalimumab, etanercept, and tocilizumab therapy.
- Author
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Boqaeid A, Layqah L, Alonazy A, Althobaiti M, Almahlawi AZ, Al-Roqy A, Baharoon O, Alsaeedi A, Shamou J, and Baharoon S
- Subjects
- Humans, Saudi Arabia epidemiology, Male, Female, Retrospective Studies, Adult, Middle Aged, Arthritis, Rheumatoid drug therapy, Antirheumatic Agents adverse effects, Antirheumatic Agents therapeutic use, Inflammatory Bowel Diseases drug therapy, Arthritis, Juvenile drug therapy, Arthritis, Psoriatic drug therapy, Young Adult, Aged, Antibodies, Monoclonal, Humanized adverse effects, Antibodies, Monoclonal, Humanized therapeutic use, Adalimumab therapeutic use, Adalimumab adverse effects, Etanercept adverse effects, Etanercept therapeutic use, Tuberculosis epidemiology, Tuberculosis drug therapy
- Abstract
Background: The risk of infection including tuberculosis (TB) infection or reactivation during biological therapy with the current various clinical application is a major concern. This risk may be higher in countries endemic to TB. Our aim of this study is to determine the risk of TB infection in patients receiving 3 biological treatments, Adalimumab, Etanercept and Tocilizumab., Methods: A retrospective cohort study extending over 2 years follow-up for all patients receiving Adalimumab, Etanercept and Tocilizumab for various clinical indications in a tertiary care center in Saudi Arabia., Result: Over the period of 2015-2019, A total of 410 patients received Adalimumab, 271 received Etanercept and 58 patients received Tocilizumab. Rheumatoid arthritis was the most common indication for therapy in all groups and for Adalimumab the most common indication was inflammatory bowel disease, for Etanercept was psoriatic arthritis and for Tocilizumab was juvenile idiopathic arthritis. After a mean follow up period of 36 ± 8.9 months for patients receiving Adalimumab, 21.5 ± 8.4 months for patients receiving Etanercept and 21 ± 2.5 months for patients receiving Tocilizumab there were no reported cases of TB infection in all groups. Only one patient was diagnosed with latent TB 7 months later after starting Adalimumab and tow patients after starting Etanercept. The overall Interferon Gamma Release Assays (IGRA) positivity rate was 9.7%. There was significant association between IGRA positivity rate and patient age. The cutoff age in which IGRA positivity has significantly increased was 53.20 years., Conclusion: In our study, patients receiving Etanercept, Adalimumab and Tocilizumab had no increased risk of TB infection. Only 0.3% of patients treated with Adalimumab and 0.9% of patients treated with Etanercept converted to a positive IGRA during therapy., Competing Interests: Declaration of Competing Interest We have no conflict of interest to declare., (Copyright © 2024. Published by Elsevier Ltd.)
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- 2024
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32. A Rare Case of Parotid Stone Adherence to the Facial Nerve.
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Althobaiti M, Alharbi NS, Alhajlah A, Althwiny FA, and Amin MK
- Abstract
This case report details a complex case of parotid gland sialolithiasis with stones adherent to the facial nerve, a scenario that presents a significant surgical challenge. Traditional sialendoscopy failed to address the condition in a 23-year-old female patient, leading to the adoption of a combined endoscopic transcutaneous approach. This method successfully resolved the condition without intraoperative complications, maintaining intact facial nerve function postoperatively. The case emphasizes the importance of individualized surgical strategy and expert technique in advanced parotid surgery, advocating this approach for similarly complex sialolithiasis cases., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Althobaiti et al.)
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- 2024
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33. The Influence of Gender and Education on Awareness About Sexually Transmitted Diseases Among King Saud University and Imam Mohammed Ibn Saud Islamic University Students in Riyadh, Saudi Arabia.
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ALDosari M, Abuzied T, Alhussaini N, Althobaiti M, Tumihi Y, Alhumaid T, and AlRumayan A
- Abstract
Background: Sexually transmitted diseases (STDs) are a global issue facing the world. In a conservative community like Saudi Arabia, discussing such matters is considered taboo, and this might impact the awareness of STDs. Therefore, this study aims to determine if gender, level of education, and university affiliation influence the level of awareness of STDs., Methods: This research is a cross-sectional study that involves 389 students who are studying at King Saud University (KSU) and Imam Mohammad Ibn Saud Islamic University (IMAMU). Twenty-six questions were gathered from a previous study and implemented into the questionnaire and were validated after., Results: Overall, awareness about STDs was poor. Females scored higher than male participants (7.9 ± 3.3 vs. 7.1 ± 3.2, p < 0.017) respectively. Interestingly, undergraduates scored higher than postgraduates (4.7 ± 3.7 vs. 3.7 ± 3.3, p < 0.029). For the university, KSU students scored higher than their counterparts did at IMAMU (10.4 ± 5.7 vs. 8.9 ± 5.5, p < 0.01)., Conclusion: Female participants have shown a higher level of STD awareness than males, but the overall awareness is still extremely low. However, KSU scored higher than IMAMU As a result, appropriate education and promotion efforts about STDs must be implemented based on gender and education level., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, ALDosari et al.)
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- 2024
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34. 7-Hydroxy Frullanolide Ameliorates Isoproterenol-Induced Myocardial Injury through Modification of iNOS and Nrf2 Genes.
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Ullah S, Ahmad T, Ikram M, Rasheed HM, Khan MI, Khan T, Alsahli TG, Alzarea SI, Althobaiti M, and Shah AJ
- Abstract
Myocardial infarction (MI) is the principal cause of premature death. Protecting myocardium from ischemia is the main focus of intense research. 7-hydroxy frullanolide (7-HF) is a potent anti-inflammatory agent, showing its efficacy in different acute and chronic inflammatory disorders such as atherosclerosis, suggesting it can be a potential cardioprotective agent. For the induction of MI, Sprague-Dawley rats (n = 5) were administered isoproterenol (ISO) 85 mg/kg s.c at 24 h intervals for two days. The potential cardioprotective effect of 7-HF and its mechanisms were explored by in vivo and in vitro methods. 7-HF significantly prevented the extent of myocardial injury by decreasing the infarct size, preserving the histology of myocardial tissue, and reducing the release of cardiac biomarkers. Further, 7-HF increased the mRNA expression of cardioprotective gene Nrf2 and reduced the mRNA expression of iNOS. 7-HF also improved cardiac function by decreasing the cardiac workload through its negative chronotropic and negative ionotropic effect, as well as by reducing peripheral vascular resistance due to the inhibition of voltage-dependent calcium channels and the release of calcium from intracellular calcium stores. In conclusion, 7-HF showed cardioprotective effects in the MI model, which might be due to modulating the expression of iNOS and Nrf2 genes as well as improving cardiac functions.
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- 2023
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35. Recent Advances in Smart Epidural Spinal Needles.
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Althobaiti M, Ali S, Hariri NG, Hameed K, Alagl Y, Alzahrani N, Alzahrani S, and Al-Naib I
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- Needles adverse effects, Spinal Puncture adverse effects, Spinal Puncture methods, Central Nervous System, Anesthesia, Epidural, Anesthesia, Spinal adverse effects, Anesthesia, Spinal methods
- Abstract
Lumbar puncture is a minimally invasive procedure that utilizes a spinal needle to puncture the lumbar epidural space to take a sample from the cerebrospinal fluid or inject drugs for diagnostic and therapeutic purposes. Physicians rely on their expertise to localize epidural space. Due to its critical procedure, the failure rate can reach up to 28%. Hence, a high level of experience and caution is required to correctly insert the needle without puncturing the dura mater, which is a fibrous layer protecting the spinal cord. Failure of spinal anesthesia is, in some cases, related to faulty needle placement techniques since it is blindly inserted. Therefore, advanced techniques for localization of the epidural space are essential to avoid any possible side effects. As for epidural space localization, various ideas were carried out over recent years to provide accurate identification of the epidural space. Subsequently, several methodologies based on mechanical and optical schemes have been proposed. Several research groups worked from different aspects of the problem, namely, the clinical and engineering sides. Hence, the main goal of this paper is to review this research with the aim of remedying the gap between the clinical side of the problem and the engineering side by examining the main techniques in building sensors for such purposes. This manuscript provides an understanding of the clinical needs of spinal needles from an anatomical point of view. Most importantly, it discusses the mechanical and optical approaches in designing and building sensors to guide spinal needles. Finally, the standards that must be followed in building smart spinal needles for approval procedures are also presented, along with some insight into future directions.
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- 2023
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36. A Clot in Transit: A Cause of Death or a Bystander?
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Almahlawi AZ, Alghamdi M, Althobaiti M, Alahmadi D, Almalki Y, Alsahli R, Aljahdali HA, Shamou J, and Baharoon S
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Introduction: The clot in transit is a rare manifestation of thromboembolic disease occurring usually in the setting of PE and frequently associated with poor outcomes. The best therapeutic option is not well established. We describe a series of 35 patients diagnosed with clots in transit including their therapeutic interventions and outcome between the period January 2016 to December 2020., Methods: a retrospective chart review of all patients with an Echocardiogram showing thrombi in the right heart chambers including patients with thrombus in the presence of central lines or other devices. We exclude patients where masses were described as tumors or vegetation and masses in the presence of bacteremia., Results: There were 35 patients with echocardiographic evidence of a thrombus in the right heart chambers. In 12 of those patients, the thrombus was related to an intracardiac catheter. 37.1% of CT chest was done along with Echocardiogram and showed a concomitant PE in 77%. On echocardiogram, 66% of the thrombi were mobile. RV strain was present in 17% while abnormal RVSP (>30 mmHg) was present in 74%. Respiratory support was required in 37.1% and only 17% required inotropic support. There was a total or partial resolution in 80% those who had repeated echocardiogram after four weeks of therapy. Heparin was started in the majority of patients (74%). Warfarin was the most frequently used follow-up anti-coagulant in 51.4%. The mortality rate was significantly higher in those patients with RVSP >50, UFH group, O2 or inotropic support. 26% of patients died within the first 28 days after the diagnosis, while first 7 days mortality was 6% only., Conclusion: a clot in transit in our study was not directly associated with poor outcomes in the first week of therapy, UFH is still the most frequently used initial method to treat clots in transit. However, only 26% had a total resolution of clot within 4 weeks of treatment., Competing Interests: Con fl ict of interest None., (© 2023 Saudi Heart Association.)
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- 2023
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37. The impact of viability assessment using cardiac MRI and echocardiogram on the outcome of revascularization in patients with multi-vessels coronary artery disease and moderate to severe ischemic cardiomyopathy.
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Alzahrani A, Mufti H, Alswat A, Altirkistani B, Aljehani M, Jazzar A, Alutaibi F, Abushouk A, Rahimi JA, Kashkari WA, and Althobaiti M
- Subjects
- Humans, Stroke Volume, Retrospective Studies, Ventricular Function, Left, Magnetic Resonance Imaging, Coronary Artery Disease complications, Myocardial Ischemia diagnostic imaging, Cardiomyopathies diagnostic imaging, Cardiomyopathies etiology
- Abstract
Objectives: To investigate the influence of viability assessment in the management of patients with ischemic cardiomyopathy (ICM)., Methods: This retrospective cohort study included all patients with ICM with moderate to severely reduced left ventricular ejection fraction (LVEF) who underwent viability assessment using cardiac magnetic resonance imaging (MRI) and echocardiogram as modalities of imaging. In addition, LVEF, modality of choice, and treatment plans were all extracted as main variables from the electronic database. One hundred 6 patients who met the inclusion criteria from December 2014 to December 2019 were included., Results: Posttreatment LVEF improved by 5% in the viable group compared to the nonviable group ( p =0.016). Regardless of the treatment received, 6 (8.8%) patients in the viable group died due to cardiac causes after an 18-month follow-up period; in contrast, 7 (18.4%) patients died due to cardiac causes in the nonviable group. However, despite that difference, this was not statistically significant ( p =0.153). Medical therapy alone was observed in 32 (84.2%) patients in the nonviable group compared to 32 (47.1%) in the viable group ( p <0.001). Although the reduction in hospitalization for cardiac reasons was not statistically significant, the viable arm had 50% fewer hospitalizations than the nonviable arm ( p =0.051)., Conclusion: Patients with viable myocardium had better outcomes in which LVEF significantly improved posttreatment. Additionally, there was a reduction in the number of hospitalizations for cardiac reasons in the viable group compared to the nonviable group, even though the difference was not statistically significant. However, further studies with a larger number of patients are needed to determine a definite conclusion., (Copyright: © Saudi Medical Journal.)
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- 2023
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38. A 68-Year-Old Man with a Cytogenetic Diagnosis of Chronic Myeloid Leukemia and Bone Marrow Findings of Philadelphia Chromosome Translocation Between the Long Arm of Chromosomes 9 and 22, Leading to the BCR-ABL1 Fusion Gene and V617F Mutation in the JAK2 Gene.
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Warsi A, Alamoudi S, Alsuraihi AK, Althobaiti M, Daghistani M, Samarin K, Alahmadi MO, Abuyabis RG, Bogari RA, and Filimban SA
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- Aged, Humans, Male, Bone Marrow, In Situ Hybridization, Fluorescence, Janus Kinase 2 genetics, Philadelphia Chromosome, Translocation, Genetic, Diabetes Mellitus, Type 2, Leukemia, Myelogenous, Chronic, BCR-ABL Positive diagnosis, Leukemia, Myelogenous, Chronic, BCR-ABL Positive drug therapy, Leukemia, Myelogenous, Chronic, BCR-ABL Positive genetics
- Abstract
BACKGROUND Breakpoint cluster region (BCR)-Abelson murine leukemia (ABL1) and Janus Kinase-2 (JAK2) mutations have been thought to be mutually exclusive in myeloproliferative neoplasms (MNPs), but recent data suggest that they can occur together. CASE REPORT A 68-year-old man was referred to the hematology clinic because of an elevated white blood cell count. His medical history included type II diabetes mellitus, hypertension, and retinal hemorrhage. Fluorescence in situ hybridization analysis of the bone marrow was positive for BCR-ABL1 in 66/100 cells. Conventional cytogenetics was positive for the Philadelphia chromosome in 16/20 counted cells. The percentage of BCR-ABL1 was 12%. Considering the patient's age and medical comorbidities, he was started on imatinib 400 mg once daily. Further tests showed JAK2 V617F mutation positivity and absence of acquired von Willebrand disease. He was then started on aspirin 81 mg and hydroxyurea 500 mg once daily, which was later increased to 1000 mg daily. The patient achieved a major molecular response after 6 months of treatment, with undetectable BCR-ABL1 levels. CONCLUSIONS BCR-ABL1 and JAK2 mutations can co-existence in MNPs. Physicians must suspect the presence of one of the MPNs in chronic myeloid leukemia (CML) patients with persistent or increased thrombocytosis, an atypical course of the disease, or hematological abnormalities despite evidence of response or remission of CML. Therefore, testing for JAK2 should be performed accordingly. Combining cytoreductive therapy with tyrosine kinase inhibitors (TKIs) is a therapeutic option when both mutations are present, and TKI alone is not sufficient to control peripheral blood cell counts.
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- 2023
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39. Estimation of the Differential Pathlength Factor for Human Skin Using Monte Carlo Simulations.
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Althobaiti M
- Abstract
Near-infrared technology is an emerging non-invasive technique utilized for various medical applications. Recently, there have been many attempts to utilize NIR technology for the continues monitoring of blood glucose levels through the skin. Different approaches and designs have been proposed for non-invasive blood glucose measurements. Light photons penetrating the skin can undergo multiple scattering events, and the actual optical pathlength becomes larger than the source-to-detector separation (optode spacing) in the reflection-mode configuration. Thus, the differential pathlength factor (DPF) must be incorporated into the modified Beer-Lambert law. The accurate estimation of the DPF values will lead to an accurate quantification of the physiological variations within the tissue. In this work, the aim was to systematically estimate the DPF for human skin for a range of source-to-detector separations and wavelengths. The Monte Carlo (MC) method was utilized to mimic the different layers of human skin with different optical properties and blood and water volume fractions. This work could help improve the accuracy of the near-infrared technique in the measurement of physiological variations within skin tissue.
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- 2023
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40. In Silico Investigation of SNR and Dermis Sensitivity for Optimum Dual-Channel Near-Infrared Glucose Sensor Designs for Different Skin Colors.
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Althobaiti M
- Subjects
- Humans, Blood Glucose, Skin, Dermis, Water, Skin Pigmentation, Melanins
- Abstract
Diabetes is a serious health condition that requires patients to regularly monitor their blood glucose level, making the development of practical, compact, and non-invasive techniques essential. Optical glucose sensors-and, specifically, NIR sensors-have the advantages of being non-invasive, compact, inexpensive, and user-friendly devices. However, these sensors have low accuracy and are yet to be adopted by healthcare providers. In our previous work, we introduced a non-invasive dual-channel technique for NIR sensors, in which a long channel is utilized to measure the glucose level in the inner skin (dermis) layer, while a short channel is used to measure the noise signal of the superficial skin (epidermis) layer. In this work, we investigated the use of dual-NIR channels for patients with different skin colors (i.e., having different melanin concentrations). We also adopted a Monte Carlo simulation model that takes into consideration the differences between different skin layers, in terms of blood content, water content, melanin concentration in the epidermis layer, and skin optical proprieties. On the basis of the signal-to-noise ratio, as well as the sensitivities of both the epidermis and dermis layers, we suggest the selection of wavelengths and source-to-detector separation for optimal NIR channels under different skin melanin concentrations. This work facilitates the improved design of a compact and non-invasive NIR glucose sensor that can be utilized by patients with different skin colors.
- Published
- 2022
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41. Observation and motor imagery balance tasks evaluation: An fNIRS feasibility study.
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Almulla L, Al-Naib I, Ateeq IS, and Althobaiti M
- Subjects
- Adult, Feasibility Studies, Humans, Imagination physiology, Postural Balance physiology, Imagery, Psychotherapy, Motor Cortex physiology
- Abstract
In this study, we aimed at exploring the feasibility of functional near-infrared spectroscopy (fNIRS) for studying the observation and/or motor imagination of various postural tasks. Thirteen healthy adult subjects followed five trials of static and dynamic standing balance tasks, throughout three different experimental setups of action observation (AO), a combination of action observation and motor imagery (AO+MI), and motor imagery (MI). During static and dynamic standing tasks, both the AO+MI and MI experiments revealed that many channels in prefrontal or motor regions are significantly activated while the AO experiment showed almost no significant increase in activations in most of the channels. The contrast between static and dynamic standing tasks showed that with more demanding balance tasks, relative higher activation patterns were observed, particularly during AO and in AO+MI experiments in the frontopolar area. Moreover, the AO+MI experiment revealed a significant difference in premotor and supplementary motor cortices that are related to balance control. Furthermore, it has been observed that the AO+MI experiment induced relatively higher activation patterns in comparison to AO or MI alone. Remarkably, the results of this work match its counterpart from previous functional magnetic resonance imaging studies. Therefore, they may pave the way for using the fNIRS as a diagnostic tool for evaluating the performance of the non-physical balance training during the rehabilitation period of temporally immobilized patients., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2022
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42. The Coordination Behavior of Two New Complexes, [(C 7 H 10 NO 2 )CdCl 3 ] n (I) and [(C 7 H 9 NO 2 )CuCl 2 ] (II), Based on 2,6-Dimethanolpyridine; Elaboration of the Structure and Hirshfeld Surface, Optical, Spectroscopic and Thermal Analysis.
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Hermi S, Alotaibi AA, Alswieleh AM, Alotaibi KM, Althobaiti MG, Jelsch C, Wenger E, Nasr CB, and Mrad MH
- Abstract
Two novel complexes, [(C
7 H10 NO2 )CdCl3 ]n (I) and [(C7 H9 NO2 )CuCl2 ],havebeen synthesized and characterized. Single crystal X-ray diffraction revealed that in compound (I), 2,6-dimethanol pyridinium acts as a monodentate ligand through the O atom of the hydroxyl group. Contrarily, the 2,6-dimethanol pyridine ligand interacts tridentately with the Cu(II) ion via the nitrogen atoms and the two oxygen (O, O') atoms of the two hydroxyl groups. The structure's intermolecular interactions were studied using contact enrichment ratios and Hirshfeld surfaces. Following metal coordination, numerous hydrogen connections between entities and parallel displacement stacking interactions between pyridine rings dictate the crystal packing of both compounds. The aromatic cycles generate layers in the crystal for both substances. Powder XRD measurements confirmed the crystalline sample phase purity. SEM confirmed the surface homogeneity, whereas EDX semi-quantitative analysis corroborated the composition. IR spectroscopy identified vibrational absorption bands, while optical UV-visible absorption spectroscopy investigated optical properties. The thermal stability of the two materials was tested using TG-DTA.- Published
- 2022
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43. Melioidosis Pneumonia in Saudi Arabia: A Rare Case Report and Review of the Literature.
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Almarhabi H, Munshi A, Althobaiti M, Aljohani S, Abu Shanab R, and Althaqafi A
- Abstract
Melioidosis is a serious infection caused by the bacterium Burkholderia pseudomallei (B. pseudomallei) mostly found in endemic areas like Southeast Asia and Northern Australia. However, in non-endemic regions, such as Saudi Arabia, it remains somewhat rare and unknown to healthcare workers and the public. Herein, we present a case of melioidosis in a 59-year-old Bangladeshi man who presented with pneumonia. He recently returned from Bangladesh, was a known case of type 2 diabetes on metformin, and presented to the emergency department (ED) with a history of cough, shortness of breath, and fever for three weeks. He was initially misdiagnosed and treated as pulmonary tuberculosis in another hospital prior to his latest presentation. Melioidosis is a severe infection that can be misdiagnosed due to variable presentation and low awareness among healthcare workers of the disease. Diagnosis requires high clinical suspicion, especially in patients who are coming from endemic areas with appropriate risk factors such as diabetes mellitus. Treatment with appropriate antibiotics for a long duration, and outpatient follow-up is vital to reduce the risk of recurrence., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Almarhabi et al.)
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- 2022
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44. Dengue-Induced Hemophagocytic Lymphohistiocytosis: A Case Report and Literature Review.
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Munshi A, Alsuraihi A, Balubaid M, Althobaiti M, and Althaqafi A
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Hemophagocytic lymphohistiocytosis (HLH) is an uncommon fatal disease of otherwise normal but hyperactive lymphocytes and histocytes. HLH could be primary (hereditary) or secondary (acquired). Fever, hepatosplenomegaly, lymphadenopathy, and neurologic dysfunction are among the common symptoms of HLH. The diagnosis of HLH is based on clinical and biochemical findings. We report here a case of a patient infected with the dengue virus who developed HLH during hospitalization. A 63-year-old female known case of asthma on inhalers, chronic hepatitis B virus, gastritis on proton pump inhibitors, and hemoglobin H disease presented to the emergency department (ED) with a history of high-grade fever (highest recorded temperature 40° C/ 104° F), which was relieved partially by antipyretics, generalized fatigability, body aches, headache and mosquito bites for four days. The physical examination was significant for hepatomegaly of 4 cm below the right costal margin. Investigations revealed pancytopenia with elevated ferritin levels (> 40000 µg/L). Viral serology was positive for dengue NS1 antigen. After hematology consultation, a bone marrow biopsy was done, which showed trilineage hematopoiesis with increased histiocytes and occasional hemophagocytosis. Given that the patient was clinically stable and there was a clear triggering condition, we opted for supportive measures rather than HLH-specific therapy. The patient was given 2 units packed red blood cells for anemia. On the following days, the patient has no recurrence of fever, with marked improvement in the biochemical profile including ferritin level (1165 µg/L). HLH is a deleterious disease with a high fatality rate, which requires the clinician to have a low threshold for suspicion in the differentials of children and adults with symptoms of persistent fever, hepatosplenomegaly, and cytopenia. Dengue-associated HLH diagnosis is challenging, but it is very important to be recognized, as early recognition is associated with better outcomes. Physicians must work in collaboration with pathologists and microbiologists for the proper diagnosis., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2021, Munshi et al.)
- Published
- 2021
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45. COVID-19-Related Pulmonary Embolism: Incidence, Characteristics, and Risk Factors.
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Bukhari ZM, Alqarni MS, Abukhodair AW, Alzahrani AS, Alzahrani A, Alsrhani H, Alasadi F, Alotaibi AM, and Althobaiti M
- Abstract
Introduction: The 2020 world pandemic caused by the novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was initially reported in December 2019 in Wuhan, China, which has since then spread globally. Several studies on patients with coronavirus disease 2019 (COVID-19) describe a high risk of pulmonary embolism (PE). The majority of PEs in patients with COVID-19 were in the segmental arteries. Therefore, this study aims to determine the rate of PE in patients with COVID-19 at King Abdulaziz Medical City in Jeddah, Saudi Arabia. Other risk factors of PE were taken into consideration., Patients and Methods: This study is a single-center, retrospective, cross-sectional study that used a non-probability consecutive sampling technique to select the patients. The local institutional review boards approved the study protocol. Overall, 91 consecutive patients who were older than 18 years of age and who had a computerized tomography (CT) pulmonary angiography were included in this study., Results: Ninety-one patients met the inclusion and exclusion criteria, of whom 46 (50.5%) were females and 45 (49.5%) were males. The study population's age ranged from 19 to 87 with a mean age of 59 ± 15 years. PE was documented in 11 patients (12.1%). Seventy-three patients underwent CT scan angiography during COVID-19 manifestation, while 18 patients had it after recovering from COVID-19. Out of the 11 patients with PE, eight were diagnosed with PE while being COVID-19 positive, and three were diagnosed with PE after recovery from COVID-19., Conclusion: Several potential clinical implications can be concluded for this study. Firstly, effective evaluation of the risk of PE in patients with COVID-19 is based on clinical findings such as chest pain, hemoptysis, lower limb edema, and, most significantly, shortness of breath. Secondly, measuring D-dimer remains an effective test for ruling out PE in patients with COVID-19 as in patients without COVID-19., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2021, Bukhari et al.)
- Published
- 2021
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46. A Review of Non-Invasive Optical Systems for Continuous Blood Glucose Monitoring.
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Alsunaidi B, Althobaiti M, Tamal M, Albaker W, and Al-Naib I
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- Blood Glucose, Blood Glucose Self-Monitoring, Humans, Monitoring, Physiologic, Diabetes Mellitus diagnosis, Optical Devices
- Abstract
The prevalence of diabetes is increasing globally. More than 690 million cases of diabetes are expected worldwide by 2045. Continuous blood glucose monitoring is essential to control the disease and avoid long-term complications. Diabetics suffer on a daily basis with the traditional glucose monitors currently in use, which are invasive, painful, and cost-intensive. Therefore, the demand for non-invasive, painless, economical, and reliable approaches to monitor glucose levels is increasing. Since the last decades, many glucose sensing technologies have been developed. Researchers and scientists have been working on the enhancement of these technologies to achieve better results. This paper provides an updated review of some of the pioneering non-invasive optical techniques for monitoring blood glucose levels that have been proposed in the last six years, including a summary of state-of-the-art error analysis and validation techniques.
- Published
- 2021
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47. Low-Grade Endometrial Stromal Sarcoma Extending to The Right Atrium.
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Hersi RM, AlHidri BY, Al-Jifree HM, Althobaiti M, and Almaghraby HQ
- Subjects
- Female, Heart Atria diagnostic imaging, Heart Atria surgery, Humans, Hysterectomy, Middle Aged, Vena Cava, Inferior diagnostic imaging, Vena Cava, Inferior surgery, Endometrial Neoplasms surgery, Sarcoma, Endometrial Stromal diagnostic imaging, Sarcoma, Endometrial Stromal surgery
- Abstract
Endometrial Stromal Sarcoma (ESS) are very uncommon malignant tumors that make around 0.2% of the entire uterine related malignancies. They represent the endometrial stromal cells in the proliferative stage. The annual incidence of ESS is 1-2 per million women. We present an unusual case of ESS, which originates from the uterine artery through the Inferior Vena Cava (IVC) and extends to the right atrium. A 48 years old woman presented with menorrhagia and right flank pain for seven months. Physical examination was normal except for a palpable suprapubic mass. Computed tomography (CT) showed the right gonadal vein and IVC tumoral thrombus extending into the right atrium. An echocardiogram and Transesophygeal echocardiogram revealed a large non-mobile echogenic density in the right atrium. Total abdominal hysterectomy with bilateral salpingo-oophorectomy was done. Extensive myometrial and vascular invasion was noted along with the extensive lymphovascular invasion of the uterus. Eventually, distal IVC resections were done, and there was no chance to remove the tumor because it was too attached and invaded the IVC filter. Owing to the unresectability of the tumor, the patient was assigned for palliative chemotherapy. Keywords: Endometrial Stromal Sarcoma, Right Atrium, Inferior Vena Cava, Spindle Cell Sarcoma.
- Published
- 2021
48. Polyaniline: Doping and Functionalization with Single Walled Carbon Nanotubes for Photovoltaic and Photocatalytic Application.
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Saoudi M, Zaidi B, Alotaibi AA, Althobaiti MG, Alosime EM, and Ajjel R
- Abstract
Polyaniline (PANI) was chemically doped and functionalized with single walled carbon nanotubes (SWCNTs). Various characterization methods were employed to study the structure and optical properties of PANI/SWCNTs nanocomposite, such as Fourier transform infrared (FTIR), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), optical absorption, and stationary photoluminescence. Additionally, a theoretical study using density functional theory calculations was also carried out. It has been demonstrated that the doping process may reduce the band gap without affecting the molecular structure, leading to a better compatibility with the solar spectrum. Moreover, the functionalization process with SWCNTs was able to significantly improve the properties of the resulting nanocomposite. The final interpenetrating network of PANI/SWCNTs exhibited an optical gap of nearly 2.28 eV, from which localized states induced by the charge transfer were created at nearly 1.70 eV. In addition, the resulting donor-acceptor network leads to a separation of electron holes pairs rather than their recombination, which can be used as an active layer in photovoltaic applications and a photocatalyst for advanced oxidation processes.
- Published
- 2021
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49. Patient-guided modifications of oral anticoagulant drug intake during Ramadan fasting: a multicenter cross-sectional study.
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Batarfi A, Alenezi H, Alshehri A, Balelah S, Kazim H, Algthami M, Hussain MM, Alshehri N, Alsharif R, Ashour H, Althobaiti M, Alotaibi S, Steinmetz H, and Foerch C
- Subjects
- Administration, Oral, Adult, Aged, Anticoagulants administration & dosage, Cross-Sectional Studies, Female, Humans, Male, Medication Adherence, Middle Aged, Religion and Medicine, Saudi Arabia, Anticoagulants therapeutic use, Fasting
- Abstract
Fasting Ramadan is known to influence patients' medication adherence. Data on patients' behavior to oral anticoagulant (OAC) drug intake during Ramadan is missing. We aimed to determine patient-guided modifications of OAC medication regimen during Ramadan and to evaluate its consequences. A multicenter cross-sectional study conducted in Saudi Arabia. Data were collected shortly after Ramadan 2019. Participants were patients who fasted Ramadan and who were on long-term anticoagulation. Patient-guided medication changes during Ramadan in comparison to the regular intake schedule before Ramadan were recorded. Modification behavior was compared between twice daily (BID) and once daily (QD) treatment regimens. Rates of hospital admission during Ramadan were determined. We included 808 patients. During Ramadan, 53.1% modified their intake schedule (31.1% adjusted intake time, 13.2% skipped intakes, 2.2% took double dosing). A higher frequency of patient-guided modification was observed in patients on BID regimen compared to QD regimen. During Ramadan, 11.3% of patients were admitted to hospital. Patient-guided modification was a strong predictor for hospital admission. Patient-guided modification of OAC intake during Ramadan is common, particularly in patients on BID regimen. It increases the risk of hospital admission during Ramadan. Planning of OAC intake during Ramadan and patient education on the risk of low adherence are advisable.
- Published
- 2021
- Full Text
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50. Late Complications After Previous Surgical Repair for Coarctation With Extra-Anatomic Bypass Graft: Report on Two Cases.
- Author
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Al-Husayni F, Samman A, Althobaiti M, Alghamdi A, and Alkashkari W
- Abstract
Surgical correction of aortic coarctation (CoA) has been the standard treatment in infants and adolescents to prevent late consequences related to obstruction and distal hypoperfusion. Several surgical techniques for CoA repair have traditionally been applied. However, late complications, including re-CoA and pseudoaneurysm formation, are not uncommon. The incidence of complications is highly related to the type of initial surgery. Here, we are reporting two cases of late complications related to an infrequently used surgical technique, the extra-anatomical aortic bypass graft (EABG). The first case presented with pseudoaneurysm at the distal anastomosis site with the descending aorta and treated by endovascular stent graft. The second case presented with stenosis at the proximal anastomosis site with the left subclavian artery (LSCA) and treated medically upon the request of the patient., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2021, Al-Husayni et al.)
- Published
- 2021
- Full Text
- View/download PDF
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