Formation Fe₂O₃ Nanowalls through Solvent-Assisted Hydrothermal Process and Their Application for Titan Yellow GR Dye Degradation

Ahmed, Khalid Abdelazez Mohamed Korean Chemical Society 2014 대한화학회지 Vol.58 No.2

Hematite iron oxide (${\alpha}$-$Fe_2O_3$) nanowalls were fabricated on aluminum substrate by a facile solvent-assisted hydrothermal oxidation process. The XRD and EDS patterns indicate that the sample has a rhombohedral phase of hematite $Fe_2O_3$. FE-SEM, TEM, HR-TEM, SA-ED were employed to characterize the resulting materials. $N_2$ adsorption-desorption isotherms was used to study a BET surface area. Their capability of catalytic degradation of titan yellow GR azo dye with air oxygen in aqueous solution over $Fe_2O_3$ catalysts was studied. The result indicates that the as-prepared product has a high catalytic activity, because it has a larger surface area. Langmuir and Freundlich isotherms of adsorption dye on the catalysts surface were investigated and the decomposition of titan yellow GR follows pseudo-first order kinetic.

Urgent decompression of tension pneumomediastinum in a patient to relieve elevated intracranial pressure: a case report

Ahmed Khalid Mohamed,Chan-Leveno Teresa V.,Lussier Bethany L. 대한신경집중치료학회 2022 대한신경집중치료학회지 Vol.15 No.1

Background: Timely recognition and intervention for venous outflow obstruction due to intrathoracic pathology are critical for controlling elevated intracranial pressure.Case Report: A 26-year-old man with pectus excavatum and a posterior fossa tumor requiring biopsy, decompression, and cerebrospinal fluid diversion developed pneumomediastinum following intubation with tension physiology and progressive elevation of intracranial pressure. Emergent tracheostomy was performed to decompress intrathoracic pressure, augment venous return, and ultimately expedite the patient’s definitive cancer therapy. Conclusion: Recognition of the mediastinal pathology leading to venous obstruction may be required for the management of malignant intracranial hypertension. Tracheostomy may be a means to decompress mediastinal pressure and augment venous outflow in rare cases of pneumomediastinum with tension physiology.

Utilization of mobile edge computing on the Internet of Medical Things: A survey

Ahmed I. Awad,Mostafa M. Fouda,Marwa M. Khashaba,Ehab R. Mohamed,Khalid M. Hosny 한국통신학회 2023 ICT Express Vol.9 No.3

Internet of Things (IoT) enables different smart environment objects to communicate without involving humans. Recently, IoT has started a new challenge within the healthcare sector called the Internet of Medical Things (IoMT). The huge amounts of data generated by IoMT entities need to be analyzed in real-time to improve the performance and quality of service of the IoMT applications. Mobile Edge Computing-enabled 5G system is shown as a successful paradigm to address such an obstacle. Numerous frameworks are introduced in literature based on this idea. This paper presents a thorough discussion of MEC-based IoMT healthcare systems.

Prophylactic tranexamic acid to reduce blood loss and related morbidities during hysterectomy: a systematic review and meta-analysis of randomized controlled trials

Ahmed Abu-Zaid,Saeed Baradwan,Ehab Badghish,Rayan AlSghan,Ahmed Ghazi,Bayan Albouq,Khalid Khadawardi,Nora F AlNaim,Latifa F AlNaim,Meshael Fodaneel,Fatimah Shakir Abualsaud,Mohammed Ziad Jamjoom,Abdul 대한산부인과학회 2022 Obstetrics & Gynecology Science Vol.65 No.5

To perform a systematic review and meta-analysis of all randomized controlled trials (RCTs) that evaluated the efficacyand safety of prophylactic tranexamic acid (TXA) versus a control (placebo or no treatment) during hysterectomy forbenign conditions. Six databases were screened from inception to January 23, 2022. Eligible studies were assessed forrisk of bias. Outcomes were summarized as weighted mean differences and risk ratios with 95% confidence intervalsin a random-effects model. Five studies, comprising six arms and 911 patients were included in the study. Two andthree studies had an overall unclear and low risk of bias, respectively. Estimated intraoperative blood loss, requirementfor postoperative blood transfusion, and requirement for intraoperative topical hemostatic agents were significantlyreduced in a prophylactic TXA group when compared with a control group. Moreover, postoperative hemoglobinlevel was significantly higher in the prophylactic TXA group than in the control group. Conversely, the frequencyof self-limiting nausea and vomiting was significantly higher in the prophylactic TXA group than in the control group. There were no significant differences between the groups in terms of surgery duration, hospital stay, and diarrhearate. All the RCTs reported no incidence of major adverse events in either group, such as mortality, thromboembolicevents, visual disturbances, or seizures. There was no publication bias for any outcome, and leave-one-out sensitivityanalyses demonstrated stability of the findings. Among patients who underwent hysterectomy for benign conditions,prophylactic TXA appeared largely safe and correlated with substantial reductions in estimated intraoperative bloodloss and related morbidities.

False-Positive Gallium-68 DOTATATE PET/CT in Vertebral Hemangioma

Ahmed Abdulrahman Alruwaili,Alaa Khalid Alduraibi,Alzayed Mohammed Fahed 대한핵의학회 2021 핵의학 분자영상 Vol.55 No.2

A healthy 52-year-old man started to have few minutes spells of palpitation, tachycardia, hot flashes, and chest tightness. He had a lab work-up for carcinoid, including 5-hydroxyindoleacetic acid (5-HIAA), which was negative. Months later, his symptoms became worse which warranted further investigation to exclude carcinoid disease. Gallium-68 DOTATATE positron emission tomography combined with computed tomography (PET/CT) scanning was performed to assess the patient for carcinoid tumor. It showed foci of radiotracer avidity in the thoracic and lumber spine. Magnetic resonance imaging (MRI) for the vertebral lesions showed atypical hemangioma. Subsequently, follow-up serum chromogranin A testing was negative.

Preemptive pregabalin for postoperative analgesia during minimally invasive hysterectomy: a systematic review and meta-analysis of randomized controlled trials

Ahmed Abu-Zaid,Osama Alomar,Nora F AlNaim,Fatimah Shakir Abualsaud,Mohammed Ziad Jamjoom,Latifa F AlNaim,Abdullah AMA Almubarki,Saeed Baradwan,Saud Abdullah Saud Aboudi,Faisal Khalid Idris,Meshael Fod 대한산부인과학회 2022 Obstetrics & Gynecology Science Vol.65 No.2

We aimed to perform a systematic review and meta-analysis of all randomized placebo-controlled trials (RCTs)that examined the analgesic benefits of preemptive pregabalin among patients undergoing minimally invasivehysterectomy. Five major databases were systematically screened from inception until August 29, 2021 Relevantstudies were evaluated for risk of bias. Endpoints were analyzed using the random-effects model and pooled asthe mean difference or risk ratio with a 95% confidence interval. Four studies with seven treatment arms met theinclusion criteria. The total sample size was 304 patients: 193 and 111 patients were allocated to the pregabalin andplacebo groups, respectively. Overall, the included studies revealed a low risk of bias. The summary results revealedthat the mean postoperative pain scores at rest were significantly lower in the pregabalin group than in the controlgroup at 0, 2, 4, 6, 12, and 24 hours. Moreover, the mean postoperative pain scores on movement/coughing weresignificantly lower in the pregabalin group than in the control group at 12 and 24 hours. The rate of patients whowere opioid-free postoperatively was significantly higher in the pregabalin group than in the control group. Therewas no significant difference between the groups in terms of the mean postoperative time to first rescue analgesicand the rates of adverse events. Compared with placebo, preemptive pregabalin was largely safe, and was correlatedwith superior analgesic effects in terms of lower postoperative pain scores and higher opioid-sparing effects. Additional RCTs are needed to confirm these findings.

Kinetic evaluation and study of gold-based nanoparticles and multi-walled carbon nanotubes as an alkaline phosphatase inhibitor in serum and pure form

Mohammed Samar Naser,Al-Rawi Khalid F.,Mohammed Ahmed Mishaal 한국탄소학회 2023 Carbon Letters Vol.33 No.4

In this study, gold nanoparticles (AuNPs) were synthesised using green chemistry to decorate multi-walled carbon nanotubes (MWCNTs) made from walnut shells transmission electron microscopy, field-emission scanning electron microscopy (FESEM), atomic force microscopy and fourier transforms infrared spectroscopy were used to diagnose MWCNTs and AuNPs. MWCNT-COOAu, MWCNT-COO and MWCNT-Au were diagnosed by Raman, energy dispersive X-ray analysis and FESEM. The effect of AuNPs, MWCNT-COO, MWCNT-COOAu and MWCNT-Au on pure and serum alkaline phosphatase (ALP) enzyme activity was studied in vitro using the enzyme-substrate 4-nitrophenyl disodium orthophosphate. For pure enzymes, Vmax slightly increased as the concentration of MWCNT-Au, MWCNT-COOAu and MWCNTCOO increased, whereas the Vmax values decreased as the concentration of AuNPs increased. The inhibition type for all NPs varied. For serum ALP enzyme, the Vmax values for Au-based NPs decreased as the concentration of NPs increased. The Vmax values exceeded the standard value at the concentrations of 25, 50 and 75 ppm for MWCNT-Au and MWCNT-COOAu, whereas the Vmax values increased over the standard value for all concentrations of AuNPs.

Characterization and behaviors of single walled carbon nanotube by equivalent-continuum mechanics approach

Eltaher, Mohamed A.,Almalki, Talaal A.,Ahmed, Khaled I.E.,Almitani, Khalid H. Techno-Press 2019 Advances in nano research Vol.7 No.1

This paper focuses on two main objectives. The first one is to exploit an energy equivalent model and finite element method to evaluate the equivalent Young's modulus of single walled carbon nanotubes (SWCNTs) at any orientation angle by using tensile test. The calculated Young's modulus is validated with published experimental results. The second target is to exploit the finite element simulation to investigate mechanical buckling and natural frequencies of SWCNTs. Energy equivalent model is presented to describe the atomic bonding interactions and their chemical energy with mechanical structural energies. A Program of Nanotube modeler is used to generate a geometry of SWCNTs structure by defining its chirality angle, overall length of nanotube and bond length between two adjacent nodes. SWCNTs are simulated as a frame like structure; the bonds between each two neighboring atoms are treated as isotropic beam members with a uniform circular cross section. Carbon bonds is simulated as a beam and the atoms as nodes. A finite element model using 3D beam elements is built under the environment of ANSYS MAPDL environment to simulate a tensile test and characterize equivalent Young's modulus of whole CNT structure. Numerical results are presented to show critical buckling loads, axial and transverse natural frequencies of SWCNTs with different orientation angles and lengths. The understanding of mechanical behaviors of CNTs are essential in developing such structures due to their great potential in wide range of engineering applications.

A Proposed Framework for the Automated Authorization Testing of Mobile Applications

Alghamdi, Ahmed Mohammed,Almarhabi, Khalid International Journal of Computer ScienceNetwork S 2021 International journal of computer science and netw Vol.21 No.5

Recent studies have indicated that mobile markets harbor applications (apps) that are either malicious or vulnerable, compromising millions of devices. Some studies indicate that 96% of companies' employees have used at least one malicious app. Some app stores do not employ security quality attributes regarding authorization, which is the function of specifying access rights to access control resources. However, well-defined access control policies can prevent mobile apps from being malicious. The problem is that those who oversee app market sites lack the mechanisms necessary to assess mobile app security. Because thousands of apps are constantly being added to or updated on mobile app market sites, these security testing mechanisms must be automated. This paper, therefore, introduces a new mechanism for testing mobile app security, using white-box testing in a way that is compatible with Bring Your Own Device (BYOD) working environments. This framework will benefit end-users, organizations that oversee app markets, and employers who implement the BYOD trend.

Association of Plasma Ghrelin Levels with Insulin Resistance in Type 2 Diabetes Mellitus among Saudi Subjects

Ali Ahmed Al Qarni,Faris Elbahi Joatar,Nagalla Das,Mohamed Awad,Mona Eltayeb,Ahmed Gasim Al-Zubair,Muhalab E. Ali,Abdulaziz Al Masaud,Abdirashid M. Shire,Khalid Gumaa,Hayder A. Giha 대한내분비학회 2017 Endocrinology and metabolism Vol.32 No.2

Background: Although the exact mechanism of insulin resistance (IR) has not yet been established, IR is the hallmark characteristic of type 2 diabetes mellitus (T2DM). The aim of this study was to examine the relationship between plasma ghrelin levels and IR in Saudi subjects with T2DM. Methods: Patients with T2DM (n=107, cases) and non-diabetic apparently healthy subjects (n=101, controls) from Saudi Arabia were included in this study. The biochemical profiles and plasma insulin levels of all subjects were analyzed, and IR was estimated using the homeostatic model assessment of insulin resistance (HOMA-IR) index. Active ghrelin levels in plasma were measured using the radioimmunoassay technique. Results: Only 46.7% (50 of 107) of the T2DM subjects had IR, including 26% (28 of 107) with severe IR (HOMA-IR ≥5), while 5.9% (six of 101) of the controls had moderate IR (3≤ HOMA-IR <5). HOMA-IR values were not associated with age, disease duration, or gender. Importantly, T2DM itself and the co-occurrence of IR with T2DM were significantly associated with low plasma ghrelin levels. However, ghrelin levels were inversely correlated with the HOMA-IR index, body weight, and fasting plasma insulin levels, mainly in the control subjects, which was indicative of the breakdown of metabolic homeostasis in T2DM. Conclusion: The prevalence of IR was relatively low, and IR may be inversely associated with plasma ghrelin levels among Saudi patients with T2DM.