Design of athermalized mounting structure for the sub-aperture primary mirror of a synthetic aperture telescope

The imaging quality of the synthetic aperture system is sensitive to the positioning accuracy of the sub-aperture primary mirror. A novel flexible mounting structure of bimetallic material is proposed for the athermalization of the sub-aperture primary mirror of the Fizeau Synthetic Aperture Telescope – which is composed of seven sub-aperture. The axial position accuracy of the sub-aperture primary mirror must be less than 5 µm under 10°C temperature rise to meet the requirements of the optical system. Firstly, a single mounting unit is analyzed theoretically, and the initial parameters are determined. The conceptual design of the mounting structure is carried out by using initial parameters. The orthogonal optimization algorithm and range analysis are used to optimize the structural parameters. The finite element model of the flexible mounting structure is established and the coupled thermal-mechanical simulation analysis is performed. Then the thermal sensitivity test of the sub-aperture primary mirror mounting structure was carried out. Under the effect of a temperature rise of 10°C, the axial displacement of the sub-aperture primary mirror mounting surface is less than 3 µm. Finally, the synthetic aperture system is assembled, and the optical test verifies that the synthetic aperture system has good imaging capabilities.

A giant renal angiomyolipoma: a rare case report and review of literature

Renal angiomyolipomas (AMLs) are the most common benign tumours of the kidney that occur sporadically in 80% of the patients and are seen associated with genetic conditions such as tuberous sclerosis in rest of the patients. The diagnosis of renal AML pre-operatively have been made easier with the advent of good imaging modalities. The management of these tumours depends on factors such as size, clinical presentation, extent of parenchymal involvement and ranges from a wait and watch strategy to a radical nephrectomy. Herewith, we reported of a giant renal AML who presented with complaints of lump in abdomen with headache and palpitations. She was diagnosed to have a giant renal AML on imaging. The patient was managed with radical nephrectomy after renal AML. A brief case report with review literature was presented here.

Ultrasonic Imaging of Carotid Inflammatory Plaque with Superparamagnetic Nanoparticles

Chronic inflammation can stimulate the formation and progression of atherosclerotic plaques and increase the vulnerability of plaques. However, there are few studies on the changes of carotid inflammatory plaques during treatment. Our study attempted to investigate the use of superparamagnetic iron oxide nanoparticle (SPION) ultrasound imaging to detect the expression of vascular cell adhesion molecule-1 (VCAM-1) in patients with carotid plaques and analyze the effects of SPION ultrasound imaging in inflammatory plaque visualization effect. SPION microbubble contrast agents have good imaging effects both in vivo and in vitro. We conjugated the VCAM-1 protein to the microbubbles wrapped in SPIONs to form SPIONs carrying VCAM-1 antibodies. Observe the signal intensity of SPIONs carrying VCAM-1 antibody to arteritis plaque. The results showed that the SPION contrast agent carrying VCAM-1 antibody had higher peak gray-scale video intensity than the other two groups of contrast agents not carrying VCAM-1 antibody. It shows that SPIONs have excellent imaging effects in ultrasound imaging, can evaluate the inflammatory response of arterial plaque lesions, and are of great significance for the study of carotid inflammatory plaque changes.

An all-in-one approach for synthesis and functionalization of nano colloidal gold with acetylacetone

Controllable synthesis, proper dispersion, and feasible functionalization are crucial requirements for the application of nanomaterials in many scenarios. Here, we report an all-in-one approach for the synthesis and functionalization of gold nanoparticles (AuNPs) with the simplest β-diketone, acetylacetone (AcAc). With this approach, the particle size of the resultant AuNPs was tunable by simply adjusting the light intensity or AcAc dosage. Moreover, owing to the capping role of AcAc, the resultant AuNPs could be stably dispersed in water for a year without obvious change in morphology and photochemical property. Formation of ligand to metal charge transfer complexes was found to play an important role in the redox conversion of Au with AcAc. Meanwhile, the moderate complexation ability enables the surface AcAc on the AuNPs to undergo ligand exchange reactions. With the aid of Ag+, the AuNPs underwent ligand exchange reaction with glutathione and exhibited enhanced photoluminescence (PL) with a maximum of 22-fold increase in PL intensity. The PL response was linear to the concentration of glutathione in the range of 0~500 μM. Such a ligand exchange reaction makes the obtained AuNPs being good imaging probes. To the best of our knowledge, this is the first work on illustrating the roles of AcAc as a multifunctional ligand in fabrication of NPs, which sheds new light on the surface modulation in synthesis of nanomaterials.

A New Method for Auto-Inspecting Both Opposite Surfaces of Tec Components Based on Equal-Optical-Path Imaging System

An new optical method for simultaneously inspecting opposite surfaces defects of thermoelectric cooler (TEC) components that meets condition of equal optical paths for both surfaces imaging has been proposed. The optical apparatus for surfaces defects inspection has been designed and established with “confocal” imaging system consisting of two trapzoid reflection prisms and one optical images combiner. Experimental investigations on defects inspection with the “confocal” imaging system have been carried out. The results showed that the proposed optical method can be used to simultaneously inspect the defects of opposite surfaces of TEC components without need to employ a tele-centric imaging lens with large depth of focus. It was concluded that the optical inspection method can meet the technical requirements for inspecting opposite surfaces (both side surfaces, or both top and bottom surfaces) defects of TEC components and has advantages of equal good imaging quality, increased inspection accuracy and throughput, simplified system configuration and improved system reliability etc.

The technology of artificial pneumoperitoneum CT and its application in diagnosis of abdominal adhesion

To retrospectively analyze the use of artificial pneumoperitoneum in CT scans, to explore its operation methods and technical points, and to lay the foundation for the widespread application of artificial pneumoperitoneum in CT. A total of 331 patients who underwent artificial pneumoperitoneum with CT angiography from January 1, 2013, to November 1, 2019, were recruited. All patients underwent standardized artificial pneumoperitoneum in the horizontal, left and right lateral, and prone positions during CT thin-layer scans of the abdomen and 3D reconstruction. Taking the surgical results as the gold standard, and using kappa test to verify the consistency of surgical results and imaging results. In all 331 patients, 43 patients had a normal peritoneal space, and 288 patients had an abnormal peritoneal space. And only 22 patients developed complications of subcutaneous emphysema, accounting for 6.6% of all 331 patients. In terms of the postoperative results, 28 were normal, and 303 were abnormal. The sensitivity, specificity and accuracy of CT diagnosis of abdominal adhesions using artificial pneumoperitoneum were 100%, 95.04%, and 95.46%, respectively. According to the Kappa consistency test, the imaging diagnosis from the CT scan with artificial pneumoperitoneum had a high consistency with the surgical results (kappa = 0.796, P < 0.05). The technique of artificial pneumoperitoneum CT is safe, reliable, highly practical, and proficient for obtaining good imaging results. It provides a good imaging basis for the diagnosis of intra-abdominal diseases, especially intra-abdominal adhesions.

The Application Value of MRI in the Training and Physical Rehabilitation of Gastrocnemius with Acute Sports Injury

The purpose of this study was to analyze the magnetic resonance imaging (MRI) signs of acute gastrocnemius injury and to provide the basis for clinical diagnosis. Thirty-two patients with acute gastrocnemius muscle injury (19 males and 13 females, aged 18–63 years, mean 46 years) were recruited, and MRI scans were performed. The results showed that all the lesions of calf gastrocnemius were detected in 32 patients, including first-degree injury in 15 cases, second-degree injury in 15 cases, and third-degree injury in 2 cases. MRI can display the location and pathological changes of acute gastrocnemius injury, providing good imaging data for clinical diagnosis and treatment.

An atypical presentation of a multiloculated giant pseudocyst of pancreas

Giant pseudocysts of the pancreas are rare and difficult to manage. Pseudocysts are usually treated by cystogastrostomy but dependent drainage for giant pseudocysts may require alternative methods like cystojejunostomy. We report here a rare case of a multiloculated giant pseudocyst of pancreas which presented atypically with protrusion through the lesser omentum. The pseudocyst protruding through the lesser omentum filled the whole upper abdomen up to umbilical region and displaced the stomach inferiorly. The stomach which is usually displaced anteriorly by pseudocysts was unusually displaced and splayed on the inferior aspect of the pseudocyst. The anterior wall of the fundus and body of the stomach was adherent to the inferior aspect of the pseudocyst. The pseudocyst was managed by draining into the stomach in a different way by performing a cystogastrostomy to the anterior wall of the stomach. Giant pseudocysts are difficult to manage, and good imaging studies are helpful in selecting surgical options for dependent drainage. Cystogastrostomy on the anterior wall of the stomach is a feasible option to drain pseudocysts which are predominantly overlying and adherent to the anterior wall of the stomach.

Recent Advances in Multimodal Molecular Imaging of Cancer Mediated by Hybrid Magnetic Nanoparticles

Cancer is the second leading cause of death in the world, which is why it is so important to make an early and very precise diagnosis to obtain a good prognosis. Thanks to the combination of several imaging modalities in the form of the multimodal molecular imaging (MI) strategy, a great advance has been made in early diagnosis, in more targeted and personalized therapy, and in the prediction of the results that will be obtained once the anticancer treatment is applied. In this context, magnetic nanoparticles have been positioned as strong candidates for diagnostic agents as they provide very good imaging performance. Furthermore, thanks to their high versatility, when combined with other molecular agents (for example, fluorescent molecules or radioisotopes), they highlight the advantages of several imaging techniques at the same time. These hybrid nanosystems can be also used as multifunctional and/or theranostic systems as they can provide images of the tumor area while they administer drugs and act as therapeutic agents. Therefore, in this review, we selected and identified more than 160 recent articles and reviews and offer a broad overview of the most important concepts that support the synthesis and application of multifunctional magnetic nanoparticles as molecular agents in advanced cancer detection based on the multimodal molecular imaging approach.

An Ultrastructural Study on the Effect of High Temperatures on Teeth and Restorative Materials That Aids in the Identification of Human Remains

Introduction. In most disasters, teeth are the only means of positive identification of an otherwise unrecognizable body, as there has been tremendous increase in the use of dental restorations that have different resistance to prolonged high temperature which is an important aid in identifying burned victims. Application of SEM/EDS in forensics was found useful in areas where there is a need for good imaging with high magnification combined with elemental analysis. The objective of this study was to analyze incineration effects on teeth and restorative materials using SEM/EDS. Materials and Method. 128 extracted teeth were collected, 96 were restored with silver amalgam, composite, and GIC of 32 each, and crown preparation was done in 32 teeth for which metal ceramic crowns were prepared. These teeth were subjected to 4 different temperatures (500°C, 700°C, 900°C, and 1100°C) for 20 minutes, and they were analyzed macroscopically and by using SEM for the changes subsequent to their exposure to such high temperatures. Results. All the restorations which were very difficult to identify by naked eye were identified with the help of SEM/EDS. Conclusion. Elemental analysis of the specific restorative material proves to be an essential tool for the forensic odontologist.