Differences in the Quantity and Composition of Extracellular Vesicles in the Aqueous Humor of Patients with RetinalNeovascular Diseases

Extracellular vesicles (EVs) are secreted by various cells in the body fluid system and have been found to influence vessel formation and inflammatory responses in a variety of diseases. However, which EVs and their subtypes are involved in vascular retinal diseases is still unclear. Therefore, the aim of this study was to explore the particle distribution of EVs in retinal neovascular diseases, including age-related macular degeneration, polypoidal choroidal vasculopathy, and central retinal vein occlusion. The aqueous humor was harvested from 20 patients with different retinal neovascular diseases and six patients with cataracts as the control group. The particle distribution was analyzed using nanoparticle tracking analysis (NTA) and transmitting electron microscopy (TEM). The results revealed that the disease groups had large amounts of EVs and their subtypes compared to the control group. After isolating exosomes, a higher expression of CD81+ exosomes was shown in the disease groups using flow cytometry. The exosomes were then further classified into three subtypes of exomeres, small exosomes, and large exosomes, and their amounts were shown to differ depending on the disease type. To the best of our knowledge, this is the first study to elucidate the dynamics of EVs in retinal neovascular diseases using clinical cases. Our findings demonstrated the possible functionality of microvesicles and exosomes, indicating the potential of exosomes in the diagnosis and therapy of retinal neovascular diseases.

Effect of Prestrain on Precipitation Behaviors of Ti-2.5Cu Alloy

As a special hardenable α titanium alloy, Ti-2.5 Cu alloy was a candidate material for high temperature components requiring high strength and plasticity. The effect of prestrain on the precipitation behaviors was investigated in the present study. Tensile tests show that elongation up to 22 % can be obtained after solid solution (SS) treatment. Thereafter, prestrain in tension with 5 %, 10 %, 15 % and 20 % was carried out for the SS samples and then duplex aging was applied. Transmitting electron microscopy (TEM) investigations show that larger Ti2Cu particles were observed in the prestrained condition than free aging one, as prestrain significantly speeds up the precipitation kinetics. The strength firstly increases and then decreases for the prestrained samples after duplex aging, where the competition between precipitation hardening and recovery softening should be responsible. With the consideration of SS, precipitation and recovery, a strength model for duplex aging combined with prestrain was established, which is in well agreement with experiments. Present study may provide a promising way to obtain the strength of deformed hcp materials in industry application.

One-step synthesis of metal sulfide/tellurium composites with distinct microstructures

Microsphere flower- and mushroom-shaped metal sulfide/tellurium composites were synthesized through a one-step and template-free approach in which the simultaneous formation of tellurium and NiS (or CdS) leads to well-dispersed composites. The development of such distinct microstructures has been systematically investigated as a function of reaction temperature, concentrations of the starting reagents, and reaction time. Characterizations with scanning and transmitting electron microscopy, energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and thermal gravimetric methods illustrate that the as-obtained metal sulfides exist in different phases in the composites. CdS was found to present as cubic sphalerite-type cadmium sulfide crystals, whereas NiS was in the amorphous form. Photo-excitation and emission property of the NiS/Te composite was also examined.

Microstructure and Magnetic Properties of FePt/Ag Nanocomposite Films with Perpendicular Orientation

[FePt(2 nm)/Ag(d nm)]10 mutilayers were deposited on single crystal MgO (100) substrates by magnetron sputtering. L10-FePt/Ag nanocomposite films with a high coercivity and a perpendicular orientation were achieved by annealing the as-deposited films at 600 °C for 15 min. The result of high resolution transmitting electron microscopy (HRTEM) shows apparent mutilayer structure of the [FePt(2 nm)/Ag(5 nm)]10 film. We also found the good epitaxial growth of FePt on MgO [001] direction. Atomic force microscopy (AFM) observation on the surface morphology showed that the surface particle size and roughness degree decrease with increasing the Ag layer thickness.

Microstructure of ZrB2–SiC Composite Fabricated by Spark Plasma Sintering

ZrB2-SiC composite is a promising candidate for ultra-high temperature ceramics, which is difficult to be sintered due to strong covalent bonding of ZrB2 and SiC. ZrB2-30Vol.%SiC composite was prepared by spark plasma sintering technique (SPS) at the sintering temperature of 1850°C, sintering pressure of 50MPa, heating rate of 200°C/min and holding time of 3 minutes. The phase components and microstructure were examined by X-ray diffraction, scanning electron microscopy and transmitting electron microscopy. The results show that the product is composed of ZrB2 phase, SiC phase and ZrO2 phase. A rationalization for the presence of ZrO2 phase is based on the impurity of raw material and oxidation of ZrB2 during SPS. The consolidated product is very dense and no apparent pores exist in the microstructure. ZrO2 phase with irregular shape is found among some particles as a binder phase. It is shown that the presence of ZrO2 phase may be beneficial to the densification of ZrB2-SiC composite.

Structure and Function of the Superficial Corneal Epithelium

The surface of the cornea is extremely smooth. The glassy surface of the normal cornea appears to be maintained by retention of the tear film over the epithelium. The superficial cells of the corneal epithelium have fine ridges measuring 0. 5 μ high, 0.3 μ wide, and 0. 5-1 μ long. The ridges give a worm-like appearance and are slightly less conspicuous in the central portion. There is a ridge-free zone at the cell boundary (Fig. 1A). These ridges are consistently found in all normal animals. The cytological structure viewed by transmitting electron microscopy appears similar to that of microvilli (Fig. IB).