An Unusual Case Presentation of the May-Thurner Syndrome

Summary: A 56-year-old woman underwent abdominoplasty with no immediate complications. She had no known bleeding history nor any relevant past surgical history. Adequate preventive measures for venous thromboembolism were performed, including sequential compression devices, good hydration, and early ambulation. At 17 days post operation, the patient presented to the emergency room complaining of left leg swelling and sharp, shooting pain radiating down her left leg. Workup in the Emergency Room revealed significant venous thrombosis involving complete occlusion of the major veins of the left leg. There were no indications of cardiopulmonary compromise. Angiography revealed an anatomical variant consistent with May-Thurner Syndrome (MTS). This variant first described in 1957 may present in up to one-quarter of patients, more commonly in young women. This case appears to the first reported of MTS occurring in association with a postoperative complication of abdominoplasty. Diagnosis and management considerations are discussed

The use of sol-gel technology for adhesive and structural durability applications.

The use of adhesives for joining metallic and non-metallic substrates is widely accepted in various structural engineering applications, such as aerospace, automobiles. In order to meet the industry requirements, the ability to achieve good mechanical properties under a wide variety of conditions should be considered. A major advantage of adhesive bonding over conventional mechanical fastening such as bolts and rivets is that it enables dissimilar materials to be joined. However, these materials (i.e. cured epoxy resins) are brittle and have poor resistance to cracks which indicate low capability to absorb the external energy therefore limiting their application in fields requiring high adhesive and impact strength. The incorporation of secondary components or modifiers into the epoxy system can overcome these issues. Sol-gel technology is finding increasing applications, for example, as hydrophobic selfcleaning and decorative colour coatings, formation of low-temperature cure high purity optical components and biomedical applications. The basic advantage of the sol-gel process is its ability to form inorganic structures and hybrid organic and inorganic network structures at relatively low temperatures using conventional coating techniques such as dip coat, spin coat or spraying. The present work is based upon the use of sol-gel technology to produce an adhesive which can be used to bond aluminum 2024-T3 and mild steel substrates. A novel adhesive material is produced from the combination of a hybrid silica sol-gel system, nano-inorganic particles and an epoxy polymer. The adhesive strength was investigated using a universal tensile test machine. The percentage of the bond strength of the material formed through the hybrid silica-base sol-gel is found to be related to the condensation reaction of sol-gel or via a formation of Si-O-Si networks in the adhesive. The effects of adding different concentrations of organic and inorganic materials on sol-gel adhesive strength were studied. For example, by doping a DGEBA epoxy resin, TiO[2], gamma-Al[2]O[3] MWCNT and mixture of PANI and gamma-Al[2]O[3] into the sol-gel, an increase in bond strength via the enhancement of the cross-linking among a hybrid sol-gel system was observed. The effects of cure process were investigated and it was observed that an increase in cure temperature/time led to an increase of the adhesive strength. In addition, the adhesive strength was increased as the specimen surface roughness increased due to a mechanical keying effect. Lap shear strength was also increased as bond geometry of the joint increased. The strength of the sol-gel adhesive joint has found to decrease on increasing the test temperature, being related to a softening of the sol-gel adhesive. Furthermore the adhesive strength decreased as the immersion time in 3.5%NaCI increased as a result of water absorption and the formation of corrosion products along the interfacial bond line. A study of sol-gel adhesive performance subjected to cyclic loading showed fatigue behaviour, as reported in the literature, notably increasing fatigue life with decreasing fatigue load. No significant effects in the fatigue behaviour of the lap joints were noted for different loading frequencies. FTIR, Raman and XPS analysis confirmed that improvements in the strength of the hybrid epoxy/sol-gel materials were related to the formation of different covalent bonds in the adhesive matrix, i.e. Si-O-Si, Si-O-Al and Si-O-C

The Adhesive Strength of Epoxy/Sol-Gel Materials Modified by Various Ratio of γ-Al2O3 Nanoparticles

In this study, the use of sol-gel/epoxy adhesive based on the combination of organic and inorganic components within the adhesive matrix have been studied. The combination of different amounts of γ-Al2O3 nano-particles to the adhesive matrix was evaluated. Mild steel specimens were prepared for lap joints, which were cured in an oven at 200°C for 16 hours. The bond strength of the sol-gel/epoxy matrix was investigated using a universal tensile test machine. The presence of Al-OH and/or Si-OH bonds increases causing an increase in the strength of the bulk material. This process is seen through the appearance of an absorption peak shoulder which appears in the range of ~ 1088 to1100 cm-1 which corresponds to Al-O-Si or Si-O-Si. The maximum adhesive strength of composite sol-gel/epoxy adhesive recorded was 23±0.4 MPa. This was obtained when small amounts of γ-Al2O3 nano-particles (4.0 wt%), were incorporated within the matrix. However, as the level of these inorganic materials in the adhesive matrix increased further, the adhesive shear strength gradually decreased. At a high ratio of γ-Al2O3 particles, poor interfacial bonding or adhesion between the filler and the adhesive matrix is recorded. Scanning Electron Microscopy (SEM) is used to investigate the fracture surface with 4.0 wt% γ-Al2O3, the scanning shows a very small distance of cracks, suggesting the material may act as a barrier to crack propagation and thus increases the energy required for fracture

Motivation and Hurdles for the Student Adoption of Metaverse-based Classroom: A Qualitative Study

Metaverse is an emerging technology that combines the virtual world and the real world, resulting in an immersive user experience. It has many applications. In this study, we inves-tigated the users\u27 perception of the Metaverse-based classroom in the UAE by qualitatively surveying 84 higher education students. After coding the users\u27 responses, we generated a world cloud and analyzed the user responses. A little more than a third of the surveyed users do not believe that they will benefit from using Metaverse in higher education, and they would not like to use it. Users are mainly concerned about their health conditions, security, and privacy of their information, and the students\u27 movement may result in students losing focus (distraction). On the other hand, the learner will be motivated by the interactive nature of the Metaverse-based classroom and the education\u27s location and time flexibility. Different practical and theoretical implications have been identified and discussed in this paper

The Rule of Distinct Services of Transport Companies in Customers Satisfaction: A Case Study from Royal Jordanian Airlines

This study aims to explore the extent of offering distinctive services by the Royal Jordanian Airlines transport company to the travelers on its aircraft. The study relied on data collected from the company's profile and website. And through the benchmarking between the services of Royal Jordanian Airlines with some international airlines companies, and the services standardized by the International Air Transport Association, the results showed: Royal Jordanian Airline Provides pre-flight services such as; possibility to book by phone or internet with the lowest fare, notify travelers of known delays if any, deliver baggage on time, refund of the ticket to the client in case of his apology for travel. Royal Jordanian pays more attention to the passengers with disabilities and special needs in terms of providing those comfortable seats and equipment that help them to move, in addition to kind treatment and special food. As one of the in-flight services, Royal Jordanian Airlines accepts unaccompanied minors ages 5-14 years with $100 as an escort service charge per direction. Royal Jordanian Airlines is seeking to improve the quality of food and beverages offered to passengers in terms of taking into account the conditions of diabetes and pressure. Services provided to mitigate passenger inconvenience from cancellations and misconnections are from the post-flight services

Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum