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Introduction: Coronavirus 2019 symptoms include coagulopathy and thromboembolic risk. Using one parameter to diagnose coagulopathy has little predictive value. Objective: This study will examine if D-dimer and APTT testing can predict COVID-19 severity and aid triage and manage patients. Methods: 214 COVID-19 patients were enrolled and classified into two categories based on their respiratory manifestations; mild (126 cases) and severe (88 cases). Patient data regarding age, gender, D-Dimer level, and APTT level were collected. When both D-Dimer and APTT levels were abnormal, in this study, the patient was considered to have a coagulation disorder. Indicators of coagulation in the COVID-19 patients were collected and compared between the two groups. Chi-square (Χ2) tests were used to determine the significant differences between coagulation disorders in the two groups. Results: Our findings showed that patients with coagulopathies were more likely to belong to the severe group. Within the two groups of patients, the rate of coagulation disorders was as follows: mild = 8.8 % within coagulation disorders, 4.8% within the two Groups; severe = 91.2 % within coagulation disorders, 77.8 % within the two Groups. There was a statistically significant relationship between coagulation disorder and severe COVID-19 patients compared to mild patients (p < 0.05). Conclusions: Coagulation disorders are more likely to occur in severe COVID-19 patients. D-Dimer and APTT tests are significant indicators for predicting COVID-19 severity. Our research found an abnormal pattern of coagulation disorders and COVID-19 severity that should be considered in the COVID-19 treatment protocol. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the average density, mechanical stability, and the suitability of Rhizophora spp. particleboard bonded with epoxy resin as tissue-equivalent phantom materials. The particleboards were fabricated with added epoxy at levels of 0%, 5%, 10%, and 15%. CT scan was used to evaluate the epoxy distribution. The sample with 15% epoxy level complied with the Japanese Industrial Standards. Moreover, the crystallinity was measured by microscopic analysis and X-ray diffraction (XRD). The results showed that the values of mass density and effective atomic number of the studied samples were well agreed and close to the value of water. Both microscopic analysis and XRD results showed the utility of epoxy in filling up the gaps and increasing the crystallinity. In addition, the standard deviation (SD) value of fabricated particleboard bonded with 15% epoxy resin provided a good matching with the SD value of Catphan 600 phantom. Furthermore, 15% of epoxy, as a binder material, was considered the best percentage to achieve high performance and to enhance the mechanical stability of Rhizophora particleboards. In conclusion, epoxy resin improves the mechanical and physical properties of Rhizophora spp. particleboards to be performed as a phantom material. [ABSTRACT FROM AUTHOR]

• Gamma-neutron shielding of polymer nanocomposite materials based on polypropylene and iron nanoparticles. • Simulation and theoretical values of attenuation coefficients for the fabricated samples with photon energies ranging from 30 to 2000 KeV. • The values of the Geant4 code and the EpiXS software were both found to be in excellent agreement. • Gamma-ray shielding efficacy of polymer composites samples increased as the nanoparticle content increased. An evaluation of the gamma-neutron shielding capabilities of polymer nanocomposite materials based on polypropylene and iron nanoparticles is presented in this study. The chemical composition of the materials is (100-x) PP-Fex, (where x = 0.1, 0.3, 0.5, 1, 2 and 5 wt percent). For the proposed polymer samples with photon energies ranging from 30 to 2000 KeV, the mass attenuation coefficient (MAC), a crucial parameter for studying gamma-ray shielding capability, was calculated using the Geant4 Monte Carlo code. Results were compared with those predicted by EpiXS. The values of the Geant4 code and the EpiXS software were both found to be in excellent agreement. Using the mass attenuation coefficient values, we determined the linear attenuation coefficients, electron density, effective atomic number, and half value layer for all the samples. The shielding properties of the polymer samples were also evaluated by estimating both the fast neutron removal cross-section and the mean free path of the fast neutron at energies between 0.25 and 5.5 keV. The study's findings indicate a positive correlation between the Fe nanoparticle content and the gamma-ray shielding performance of PP-Fe polymer samples. Out of the several glasses that were evaluated, it was found that the PP-Fe5 polymer sample demonstrates the highest efficacy in terms of gamma-ray shielding. Moreover, the polymer sample PP-Fe5, which consists of 5 mol% of iron (Fe), exhibits the highest value of ∑R (1.10650 cm-1) and the lowest value of the mean free path for fast neutrons. This indicates that the PP-Fe 5 possesses better gamma-neutron shielding efficiency. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the attenuation properties of epoxy resin and Rhizophora spp. particleboards bonded with epoxy resin as tissue equivalent phantom materials. The calculated linear and mass attenuation coefficients of epoxy resin and Rhizophora spp . particleboards bonded with three different weight percentages of the epoxy resin (5%, 10% and 15%) were compared with theoretical (XCOM) and experimental measurements of human liver tissue and water at the same energy levels. The 241 Am and 109 Cd point sources were used to measure the linear and mass attenuation coefficients of the samples at gamma energies; 26.3, 59.5 and 88.0 keV. The computed tomography (CT) scanner was employed to determine the mean attenuation values (CT number) for the fabricated samples and water at CT tube energy 120 kVp. The linear and mass attenuation coefficients of epoxy resin and fabricated Rhizophora spp . particleboard bonded with 15% of epoxy resin provided excellent agreement to the values of XCOM calculated in the human liver tissue and water, respectively. The CT number results showed that the epoxy resin and the Rhizophora spp . particleboard bonded with15% epoxy were in a good agreement with those of human liver tissue and water, respectively. Therefore, the overall attenuation measurements of this study verify the applicability of epoxy resin as a phantom material to mimic the human liver in CT examinations and the epoxy– Rhizophora spp. particleboard fabricated with 15% epoxy resin can be used as a tissue equivalent material corresponding to CT energy range. [ABSTRACT FROM AUTHOR]

Purpose: The study aims to evaluate precisely influence of temperature on the acoustical and physical properties of blood mimicking fluid (BMF) phantom made of polymer material. Materials & methods: Propylene glycol (PG) and polyethylene glycol (PEG) were fabricated to create artificial blood phantom. Acoustic (speed and attenuation) and physical properties (density and viscosity) of BMF were tested at specific temperatures of range 22 °C, 25 °C, 35 °C, 36 °C, and 37 °C using ultrasound signals. Results: At center frequency of 5 MHz, pulse-echo allows to acoustical (speed and attenuation) and physical (density and viscosity) values to be linearly decreased with increasing of temperature. The difference in values of speed, attenuation, density, and viscosity was nuance (±0.01, ±0.001, ±0.005, and ±0.151), respectively. Conclusions: Temperature test of range 22Co-37C° have nuance influence (±0.01, ±0.001, ±0.005, and ±0.151) on acoustical and physical properties when BMF phantom of special material of PG and PEG was used. This nuance influence may be taken in account in quality assurance of ultrasound imaging system. [ABSTRACT FROM AUTHOR]

Today, with the development of technology, different kinds of materials are being tested to increase the quality, efficiency and reliability of the materials used in the fields of space and aviation, computers, energy and health. In this direction, materials scientists and researchers from different disciplines make multidimensional analyzes and reveal the use of basic building materials in the technological field through both prototypes and simulation methods. In this way, it will be possible to use materials that can give better results than the materials currently used. In this study, polydimethylsiloxane C 2 H 6 OSi (PDMS) was prepared using zinc oxide nano powder additions according to the PDMS(ZnO) x formula, where (x =0, 2.5, 5, 7.5, 10, 15 mol %). UV–VIS spectroscopy was performed on the examined PDMS-PDMS(ZnO) 15 samples to estimate their optical properties. Transmission spectra demonstrate that the λ cutoff wavelength and color of the PDMS-PDMS(ZnO) 15 polymer samples both changed to a longer wavelength when ZnO concentration increased (stronger White). Additionally, FTIR analysis of samples were performed. Due to the physical blending of the nanoparticles with the polymeric matrix, the FTIR Spectra of the PDMS with ZnO nanoparticle samples demonstrate that no new peaks were discovered. The mass attenuation coefficient μ m of the prepared samples was calculated using the MCNP N-Particle Monte Carlo code and WinXCOM. It was discovered that the theoretical and simulation results were quite close. The addition of ZnO nanoparticles to the PDMS (ZnO) samples increased μ m values. The PDMS(ZnO) 15 polymer sample showed the lowest HVL, MFP, and TVL values of all the polymer samples due to its high ZnO content. It was included that the PDMS(ZnO) 15 is an effective promising material that could be used against gamma-radiation. • Novel polymer nanocomposites materials have been fabricated. • Characterization for nuclear shielding was conducted. • WinXCOM data were compared with the simulation findings. • The PDMS(ZnO) 15 sample has excellent gamma ray shielding properties. [ABSTRACT FROM AUTHOR]

Living cells are protected from ionizing radiation by shielding materials such as lead and concrete. This research aims to develop eco-friendly, low-cost, and non-toxic materials for use as physical radiation shielding materials. Bentonite clay and eggshell powder (ESP) were chosen for this study to develop alternative materials that can replace the usage of ordinary concrete in the construction of a physical barrier for radiation shielding. Various samples of bentonite clay concretes were prepared by adding 0%, 25%, 50%, 75%, and 100% of ESP. Four layers consisting of bismuth oxide (Bi 2 O 3), tungsten oxide (WO 3), bismuth oxide with graphene oxide (Bi 2 O 3 + GO), and tungsten oxide with graphene oxide (WO 3 + GO), loaded in epoxy matrix composites, were developed and added for enhancing concrete blocks' ability to absorb X-rays. PTW Diados with an ionization chamber was used to measure the absorbed dose of the prepared samples at X-ray tube energies of 60, 80, 100, and 120 kVp. The addition of ESP to Bentonite clay samples improved the attenuation ability of clay. The percentage of 75% ESP added to Bentonite clay is the optimum amount to achieve the best attenuation. Also, the addition of the layers significantly enhanced the block samples' ability to attenuate X-rays. On the other hand, the effectiveness of graphene oxide (GO) in increasing the X-ray attenuation capacity of WO 3 and Bi 2 O 3 depended on the applied kVp values (adding GO to Bi 2 O 3 resulted in an improvement in Bi 2 O 3 attenuation capacity at 60 and 80 kVp only). As a result, Bentonite clay blocks enriched with ESP and reinforced with Bi 2 O 3 , WO 3 , Bi 2 O 3 +GO or WO 3 +GO layers are recommended as an effective radiation shielding materials. • The optimum block mixture is combination of 75% of ESP and 25% of Bentonite clay. • Adding GO increased the X-ray attenuation capacity of WO 3 and Bi 2 O 3. • The Bi 2 O 3 , WO 3 and GO layers enhanced blocks' effectiveness as radiation shielding. [ABSTRACT FROM AUTHOR]