Determination of anterior femoral bowing to length ratio in Iranian population

Due to the existence of different races and ethnicities and their different life styles, anatomical structure of people vary from one region of the world to another. The goal of this study is to determine the anterior femoral bowing to length ratio, which can be useful for planning major medical and therapeutic projects as well as designing medical equipment (including nails, orthoses and prosthetics). Lateral X-rays of femur bones of 250 patients who referred to Taleghani hospital in recent years (2011-2016) were retrieved from hospital archives and studied. 150 patients were females and 100 were males, ages ranging from 16 to 57 years old. All patients were Iranians with different ethnical backgrounds that referred to radiology centers of Tehran and Taleghani hospital and their records were saved in these centers archive. Based on femoral length, X-rays were categorized into eight groups; 300mm, 320mm, 340mm, 360mm, 380mm, 400mm, 420mm and 440mm, which are standards for manufacturing femoral nails in Iran as well as imported nails to Iran. Results showed significant difference compared to available femoral nails on the Iranian market, which indicates that these nails are not standard for Iranian population. Data analysis was based on anterior femoral bowing to length ratio alone. Gender and age were not considered for data analysis in this study and results were conclusive for all ages and genders

Artificial intelligence investigation of three silicates bioceramics-magnetite bio-nanocomposite: Hyperthermia and biomedical applications

Objective(s): Bioactive silicate ceramics have favorable features for applying as off-the-shelf bone and artificial tissue. Calcium silicate can enhance the generation of an immediate bond with host bone without an intervening rough surface in the bone layer. However, the silicate bioceramics have some drawback regarding their mechanical properties and chemical stabilities. Materials and Methods: In this study, magnetite nanoparticles (MNPs) as reinforcement were added to the three silicate bioceramics to investigate the physical and mechanical properties as well as their magnetic behavior as a case study and compare with other calcium silicate nanocomposite which are excellent candidates for hyperthermia applications. Then the artificial neural network (ANN) applied to the previous data to predict the mechanical and biological behavior of the bio-nanocomposite as output parameters. A predicted model was enhanced using ANN to measure the optimum size and reinforcement amount of the magnetite bio-nanocomposite. The results of the fabricated bio-nanocomposite were extracted experimentally corresponding to different MNPs weight fractions compared to the predicted model. Results: The X-ray diffraction (XRD), scan electron microscopy (SEM) technique were used to compare the porosity and porous tissue microstructure. Thereafter, an analytical solution is presented to express explicitly the physical and mechanical responses of the bulk/scaffold bio-nanocomposite. Conclusion: The obtained results showed the potential application of these calculations and analyses in a wide range of numerical studies. The comparison presented within the test and predicted values showed that the modeling outcomes were close to testing values

Mathematically and experimentally defined porous bone scaffold produced for bone substitute application

Objective (s): Artificial bone implants have been studied as a possible bone replacement for fractured and destroyed facial tissue; the techniques employed to determine the success of the dental implants. The stability, porosity and resistance of the bone implant which is subjected to varying forces and stresses within the surrounding bone is a subject of interest among the dentists. Materials and Methods: An experimental analysis was conducted on bio-nanocomposite scaffold using space holder methods. The reaction of the bio-nanocomposites deformation under load was determined using Abaqus software. Thereafter, an analytical solution was presented to express explicitly the deformation responses of the artificial bone implant. Results: It was seen that the vibrational behavior and mechanical performance of the sample containing 15 wt% additives have shown better mechanical characteristic compared to the pure specimen. On the other hand, the additive weight fraction has a significant effect on the compression test and porosity value. Also, the elastic modulus of the samples increases more than two times with the addition of additive (from 60 MPa to 145 MPa). From the results, it can be concluded that the highest vibration variation is seen in the sample with lower MNPs percentages.Conclusion: By observing the results of the stresses, it was seen that the stresses were in a small value in the bio-nanocomposites with highest amount of reinforcement

Novel smart composite materials for industrial wastewater treatment and reuse

Abstract: With the current levels of industrial development it is very difficult to prevent organic pollutants and toxic heavy metals from contaminating water. Thus purification of contaminated industrial water and its reuse is a global concern. The present study highlights application of a novel standalone technology in the form of polymers that efficiently extract a range of organic and inorganic impurities simultaneously for reuse of industrial effluent. Previous studies have focused on water soluble synthetic polymers for removal of organic contaminants, while biodegradable polymers are being used for extraction of toxic metals from water. Our earlier reports already describe a combination of synthetic and natural polymers with the ability to eliminate organic and inorganic spiked impurities from water on a lab scale. In the present work a series of novel smart composite materials have been synthesized and fully characterized. The avant-garde novelty of these materials for simultaneous removal of organic impurities such as phenols, anhydrides, textile dyes, pesticides, herbicides, antibiotics and inorganic heavy metals has been demonstrated and the novel polymers have shown a removal efficiency of more than 90% for each of the contaminants. Furthermore, the established 4-cycle reusability and an extensive reduction in levels of chemical oxygen demand suggests these materials would act as an improvement to the current methods for treating effluent water. The high reproducibility in synthesis, properties and elimination spectrum brands them as promising materials for industrial water remediation and reuse

The effects of material formulation and manufacturing process on mechanical and thermal properties of epoxy/clay nanocomposites

A holistic study was conducted to investigate the combined effect of three different pre-mixing processes, namely mechanical mixing, ultrasonication and centrifugation, on mechanical and thermal properties of epoxy/clay nanocomposites reinforced with different platelet-like montmorillonite (MMT) clays (Cloisite Na+, Cloisite 10A, Cloisite 15 or Cloisite 93A) at clay contents of 3–10 wt%. Furthermore, the effect of combined pre-mixing processes and material formulation on clay dispersion and corresponding material properties of resulting composites was investigated using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), flexural and Charpy impact tests, Rockwell hardness tests and differential scanning calorimetry (DSC). A high level of clay agglomeration and partially intercalated/exfoliated clay structures were observed regardless of clay type and content. Epoxy/clay nanocomposites demonstrate an overall noticeable improvement of up to 10 % in the glass transition temperature (Tg) compared to that of neat epoxy, which is interpreted by the inclusion of MMT clays acting as rigid fillers to restrict the chain mobility of epoxy matrices. The impact strength of epoxy/clay nanocomposites was also found to increase by up to 24 % with the addition of 3 wt% Cloisite Na+ clays. However, their flexural strength and hardness diminished when compared to those of neat epoxy, arising from several effects including clay agglomeration, widely distributed microvoids and microcracks as well as weak interfacial bonding between clay particles and epoxy matrices, as confirmed from TEM and SEM results. Overall, it is suggested that an improved technique should be used for the combination of pre-mixing processes in order to achieve the optimal manufacturing condition of uniform clay dispersion and minimal void contents

Calcium phosphate coatings: morphology, micro-structure and mechanical properties

Many biomedical implant coating systems consist of micro-deposited calcium phosphate droplets thermally sprayed onto a commercially pure Ti (CP Ti) substrate. In this study, the morphology of solidified droplet “splats” was examined using Scanning Electron Microscopy (SEM). The topography of splats sprayed onto substrates at room temperature (25 °C) and preheated to 100 °C and 300 °C was investigated. The splat shape was found to be strongly dependent on substrate preheating temperature. A homogeneous deposit density of amorphous calcium phosphate in splats deposited onto the cold substrate was confirmed by micro-Raman spectroscopy, whereas a very early stage of re-crystallization was detected using Transmission Electron Microscopy (TEM) for splats deposited onto 300 °C preheated substrates. TEM in conjunction with Focused Ion Beam (FIB) revealed the splats' ultra micro-structure. Correlation of Atomic Force Microscopy (AFM) with these results enabled links between different types of micro structures and true splat contacts with the substrates to be shown. Splats deposited onto the substrate at 300 °C showed generally well-adherent interfaces. The established presence of a thin layer of native oxide on this polished and preheated surface could serve to enhance the splat-substrate adhesion. Nano-indentation revealed that splats deposited onto the substrates at room temperature and 100 °C have similar hardness and elastic modulus values; however, preheating the substrate up to 300 °C improved these micro-mechanical properties. These combined findings promote further understanding of the extrinsic properties of the bulk calcium phosphate coating