Image Encryption and Stegenography Based on Computational Single Pixel Imaging

Multiple layers of information security are introduced based on computational ghost imaging (CGI). We show, in the first step, that it is possible to design a very reliable image encryption scheme using 3D computational ghost imaging with two single-pixel detectors sending data through two channels. Through the Normalized Root Mean Square scale, it is then shown that a further level of security can be achieved by merging data-carrying channels into one and using a coded order for their placement in the sequence of bucket data carried by the single channel. Yet another layer of security is introduced through hiding the actual grayscale image inside another image such that the hidden image cannot be recognized by naked eyes. We then retrieve the hidden image from a CGI reconstructed image. It is shown that the proposed scheme increases the security and robustness such that an attacker needs more than 96 percent of the coded order to recover the hidden data. Storing a grayscale image in a ghost image and retrieving different intensities for the hidden image is unprecedented and could be of interest to the information security community

Bone Regeneration: Current Status and Future Prospects

The ability of bone to heal with practically no scarring is the most extraordinary feature of it. However, perturbations of the fracture site could disrupt the repair process when defects reach a critical size, resulting in non‐union. Current therapies include allografting, autografting, applying vascularized grafts, and other bone transport techniques. However, although commonplace in orthopaedic surgery, these treatments have some limitations

Characterization and numerical simulation of a new microfluidic device for studying cells-nanofibers interactions based on collagen/PET/PDMS composite

Introduction: Recently, membrane microfluidic chips (MFCs) have become available to study biological basement membranes. The nanofiber (NF) membranes are suitable substrates for cell attachment and trapping, as demonstrated by their surface properties. In this study, a novel microfluidic device based on the electrospun collagen-modified polyethylene terephthalate (PET)/polydimethylsiloxane (PDMS) was designed and fabricated to mimic biological basement membranes.Methods: Hybrid NF containing PDMS/PET and collagen were successfully fabricated by two-nozzle electrospinning, and then PDMS chips were fabricated by soft lithography. The integrity of the membrane and NFs structure before (BC) and after cross-linking (AC) was evaluated by SEM, AFM, contact angle, FT-IR, BET, and tensile analysis. For further studies, numerical simulations were performed to evaluate the microfluidic flow in the PDMS-based device and demonstrate the fluid flow on top of a membrane. In the simulation, we used COMSOL Multiphysics to study the influence of flow rate and different surface topographies on the velocity and shear rate characteristics.Results: Cross-linking of NFs increased the diameter of NF (from 391 ± 169 nm to 660 ± 199 nm), hydrophilicity, elongation, and surface roughness (from 66.9 nm to 296.7 nm), but decreased the pore size volume of NFs (0.06 cm3 g−1 to 0.01 cm3 g−1). Bonding of NFs was possible through the use of oxygen plasma activated materials based on PDMS and PET. After bonding the NFs in the channels with oxygenated plasma, human umbilical vein endothelial cells (HUVEC) and glial cell line (C6) were successfully cultured and stained in MFC with dynamic conditions for 24 h at a flow rate of 10 μl/min.Discussion: The rougher microchannels exhibited a non-uniform shear rate distribution, and the flow rate was a parameter with a significant influence on the shear rate and velocity (roughness=0.3 µm). These results provided reliable evidence that the combination of electrospun NFs and cell culture can closely resemble a cell matrix

Ocular toxoplasmosis and retinal detachment: five case reports

BACKGROUND: Ocular toxoplasmosis is a potentially blinding cause of posterior uveitis. Retinal detachment is rare complication of ocular toxoplasmosis. AIM: To report the clinical course and prognosis of retinal breaks and detachments occurring in patients with ocular toxoplasmosis. PATIENTS AND METHODS: This study was a retrospective, non-comparative case series of five patients with ocular toxoplasmosis who had consulted us with retinal detachment. RESULTS: All of the participants had retinal detachment after severe and treatment resistant toxoplasmic retinochoroiditis, leaving one of them with decreased visual acuity to light perception in spite of treatment and final visual acuity was 20/100 or better in four patients. CONCLUSIONS: The functional prognosis for the patients with retinal detachment was poor. Careful retinal examination in ocular toxoplasmosis is warranted, especially in patients with severe intraocular inflammation

An analysis of underlying factors for implementing privatization in Iranian sport

The purpose of this research was to analyze the underlying factors of privatization implementation in Iran's sport, which was developed by developmental approach. Statistical population of this research was consisted of all managers and experts involved in sports privatization in the country. Regarding that this is a qualitative research, a total of 20 people were selected using the snowball purposeful sampling technique as a statistical sample. The data collection tool was interview. Interviews continued until the theoretical saturation stage was fulfilled. The data obtained from interviews were analyzed in three stages of open, axial and selective coding. The results of the research identified 41 concepts and 5 categories including factors related to financial market, management factors, media factors, cultural factors and legal factors that provide the platform for implementation of privatization in the sport of the country. According to the results of this research, privatization in Iran's sport has been affected by various conditions, it is suggested that sport authorities are encouraged to provide a condition in which people can be trained in order to gain specialty to enter in various areas such as advertising private sector and proper culture creation in press and TV and paying attention to philosophy of sport and culture creation among the people