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Histopathology images are important for cancer diagnosis and prognosis. We extracted quantitative morphological features from breast cancers images and systematically analyzed their relationships with proteins and mRNAs. We observed concordant correlation patterns between image-protein and image-RNA and identified four cancer-related biological processes associated with morphological features related to different tumor components. Further, we observed that proteomic data reveal unique protein-related biological processes associated with morphology. Finally, prognostic morphological features were identified, and their roles are consistent with the underlying biological processes.

The GH4169 superalloy with different content of δ-Ni3Nb phase was welded by tungsten inert gas welding. A detailed study of microstructure and hardness of heat-affected zone (HAZ) was performed in both as-welded and aged state. The results show that the precipitation of δphase, especially the intergranular δphase, can lead to the enrichment of Nb and Mo elements, which promote the formation of γ/Laves eutectic constituent at grain boundaries in HAZ. In as-welded state, the hardness decreases first and then increases (exhibiting a “V” shape) with distance away from fusion line in HAZ, which is governed by grain size. After aging treatment, however, the γ″ phase plays a key role in hardness and leads to the “Λ” shape profiles of hardness in HAZ.

The natural melanin is one kind of ubiquitous biological pigments, which is produced in melanosomes and widely distributed in living organisms. The synthetic melanin, often known as polydopamine (PDA), has similar chemical compositions and physical properties to natural melanin. In recent years, both natural melanin and PDA have aroused increased research interests in biomedical fields owing to their inherent biocompatibility, antioxidant activity, free-radical scavenging, metal ion chelation, strong near-infrared absorption and high photothermal conversion efficiency. Inspired by these fascinating properties, melanin and PDA have been widely used as building blocks for the construction of multifunctional nanoplatforms for various biomedical applications. This review focuses on the state-of-the-art progress in melanin/PDA-based nanomaterials, which covers from their preparation methods to biomedical applications including bioimaging, treatment, theranostics, antibacterial, UV/radiation protection, biosensor and tissue engineering. Moreover, the current trends and the future prospects of melanin/PDA-based nanomaterials are also discussed.

The process of liver fibrosis changes the rheological properties of liver tissue. This study characterizes and compares liver fibrosis stages from F0 to F4 in rats in terms of shear viscoelastic moduli. Here two viscoelastic models, the Zener model and Voigt model, were applied to experimental data of rheometer tests and then values of elasticity and viscosity were estimated for each fibrosis stage. The results demonstrate that moderate fibrosis (≤F2) has a good correlation with liver viscoelasticity. The mean Zener elasticity E1increases from (0.452±0.094) kPa (F0) to (1.311±0.717) kPa (F2), while the mean Voigt elasticity Eincreases from (0.618±0.089) kPa (F0) to (1.701±0.844) kPa (F2). The mean Zener viscosity increases from (3.499±0.186) Pa·s (F0) to (4.947±1.811) Pa·s (F2) and the mean Voigt viscosity increases from (3.379±0.316) Pa·s (F0) to (4.625±1.296) Pa·s (F2). Compared with viscosity, the elasticity shows smaller variations at stages F1 and F2 no matter what viscoelastic model is used. Therefore, the estimated elasticity is more effective than viscosity for differentiating the fibrosis stages from F0 to F2.

MEMS devices, Micro Electro-Mechanical Systems, are electrical and mechanical systems with characteristic dimensions on the order of microns. Since these systems have moving mechanical parts, characterization of their dynamics, including their modal parameters, is highly desirable. This paper describes the validation of an existing implementation of the Stochastic Subspace Identification (SSI) algorithm, called MACEC, for experimental modal analysis of a micro-cantilever switch. A white noise signal applied to the built-in electrostatic actuator in the switches excited a response measured using microscanning Laser Doppler Vibrometry (LDV). The modal parameters found using MACEC matched well those predicted by theory, thus validating this combination for experimental modal analysis of MEMS structures.

Abstract: Golay codes are the most practical code in coded ultrasound imaging systems. But the trade-off for perfect range sidelobe cancellation is the requirement for two firings, thus resulting in motion-dependent decoding errors. In view of this, we propose a new scheme using the simultaneous emission of code pairs. The code pair is allocated to different elements of an aperture and transmitted simultaneously. The process of separating the code pair from the echo received is based on the orthogonality of the code pair. At last the autocorrelation functions of the individual Golay codes are added together. The simultaneous emission of code pairs instead of two firings recovers the frame rate loss, and eliminates the motion-dependent decoding error. Our theoretical analysis and simulations show that the scheme can be used to eliminate the tissue motion effects.

Quantitative evaluation of repairing effect of bone grafting material is one of the essential studying subjects. However, traditional evaluation methods are subjective and qualitative. In this paper, the region of new bone from a bone repairing biomaterial planted image is extracted based on color image segmentation and then statistically analyzed to evaluate the property of bone grafting material quantitatively. HSI color model, which corresponds with people’s vision system for color is used to achieve ideal segmental results and effective utilization of color information. The S and I variable are used as thresholding condition for image segmentation, thereby obtaining the area of new bone. The effect of BMP contained in BMP/α-TCP is estimated furthermore. Experimental results show that the composite BMP/α-TCP induce more bone than pure α-TCP in virtue of BMP. This study provides theoretical and experimental suggestions for clinical applications of BMP/α-TCP.

The surface morphology of film material directly affects its physical performance. It is of great significance for finding out its prospective physical performance to characterize the surface morphology of film material. It is hard to characterize them with some conventional methods. The surface morphology of film material was described from the fractal point of view, and the dimension was correlated with the resistivity of material. The [100]-orientated diamond film was primarily investigated. The results show that the greater the crystal grain is, the more uniform and regular the orientation is; and the more compact the arrangement is, the greater the fractal box dimension is. Moreover, when fractal box dimensions were within a certain range approximately from 2.92 to 2.97, it presents positively correlative relation with the logarithm of resistivity, Log(ρ), which resembles the Logistic curve. However, when the other dimensions are beyond the range mentioned above, resistivity doesn’t change with the increase in dimensions of fractal. This study will conduce to illustrating the relationship between the structure of crystal exemplified by arrangement and physical performance as well as material preparation.