Shear Wave Elastography Combined with Thyroid Imaging Report and Data System for Risk Stratification of Thyroid Nodule Malignant Tumor

Benign and malignant thyroid cancer diagnosis is crucial. Our study intends to evaluate the role of shear wave elastography (SWE) and thyroid imaging report and data system (TI-RADS) in diagnosing the benign and malignant thyroid nodules. 100 thyroid nodules patients were recruited and evaluated by SWE and TI-RADS before fine needle biopsy and/or surgery. The maximum elastic index (Emax), mean elasticity index of thyroid nodules (Emean), minimum elastic index (Emin) and elastic ratio (ER) was measured and compared between different imaging. Ultrasound diagnosis showed solid nodules with significant hypoechoic, unclear boundary, and microcalcification. TI-RADS value was measured based on suspected ultrasound features. Combination of SWE and TI-RADS was performed. Among the 100 nodules, 38 were benign (38.0%), 62 were malignant (62.0%), and malignant nodules had significantly elevated SWE and TI-RADS compared with benign nodules (P < 0.001). The optimal SWE threshold for Emax was 51.95 kPa, with a sensitivity of 81.44% and specificity of 83.19%. There were two methods for combining SWE and TI-RADS. One was sequential detection, with a specificity of 95.80%, positive similarity ratio of 18.16 and PPV of 96.73%; the other was parallel detection method with a sensitivity of 94.85%, negative similarity ratio of 0.07 and PPV of 90.00%. Our results suggest that combination of SWE and TI-RADS might be applied to identify benign and malignant thyroid cancers.

A Simple Model to Relate the Elastic Ratio Gamma of a Critically Self-Organized Spring-Block Model with the Age of a Lithospheric Downgoing Plate in a Subduction Zone

In 1980, Ruff and Kanamori (RK) published an article on seismicity and the subduction zones where they reported that the largest characteristic earthquake (Mw) of a subduction zone is correlated with two geophysical quantities: the rate of convergence between the oceanic and continental plates (V) and the age of the corresponding subducting oceanic lithosphere (T). This proposal was synthetized by using an empirical graph (RK-diagram) that includes the variables Mw, V and T. We have recently published an article that reports that there are some common characteristics between real seismicity, sandpaper experiments and a critically self-organized spring-block model. In that paper, among several results we qualitatively recovered a RK-diagram type constructed with equivalent synthetic quantities corresponding to Mw, V and T. In the present paper, we improve that synthetic RK-diagram by means of a simple model relating the elastic ratio γ of a critically self-organized spring-block model with the age of a lithospheric downgoing plate. In addition, we extend the RK-diagram by including some large subduction earthquakes occurred after 1980. Similar behavior to the former RK-diagram is observed and its SOC synthetic counterpart is obtained.

Quantification of Pancreatic Stiffness on Intraoperative Ultrasound Elastography and Evaluation of its Relationship With Postoperative Pancreatic Fistula

“Soft pancreas” has often been reported as a predictive factor for postoperative pancreatic fistula (POPF) after pancreatectomy. However, pancreatic stiffness is judged subjectively by surgeons, without objective criteria. In the present study, pancreatic stiffness was quantified using intraoperative ultrasound elastography, and its relevance to POPF and histopathology was investigated. Forty-one patients (pancreatoduodenectomy, 30; distal pancreatectomy, 11) who underwent intraoperative elastography during pancreatectomy were included. The elastic ratio was determined at the pancreatic resection site (just above the portal vein) and at the remnant pancreas (head or tail). Correlations between the incidence of POPF and patient characteristics, operative variables, and the elastic ratio were examined. In addition, the relationship between the elastic ratio and the percentage of the exocrine gland at the resection stump was investigated. For pancreatoduodenectomy patients, main pancreatic duct diameter &lt; 3.2 mm and elastic ratio &lt; 2.09 were significant risk factors for POPF. In addition, the elastic ratio, but not main pancreatic duct diameter, was significantly associated with the percentage of exocrine gland area at the pancreatic resection stump. Pancreatic stiffness can be quantified using intraoperative elastography. Elastography can be used to diagnose “soft pancreas” and may thus be useful in predicting the occurrence of POPF.

Friction of Rough Soft Matter Contacts: Local Investigations Through Image Correlation Technique

The friction induced in contacts is a key feature concerning functionality of mechanisms, reliability of systems, energy consumption… Friction on soft matter occurs in many applications (tire/road contacts, touch-sensitive exploration, micro-manipulation of biological items…) as well as in nature. The latter offers various examples of how a topographic surface pattern may control friction. The result is a complex combination of phenomena: adhesion, elastic ratio of bodies in contact, viscous flow, plasticity occurrence, and topography interaction. The role of this latter phenomenon essentially lies in the splitting of the contact area between the two contacting materials and plays an important role on friction response when coupled with adhesion.

Preparation and Characterization of Thermoplastic Soy Protein Isolate

A soybean protein isolate (SPI) main chain grafted with methyl acrylate (MA) and methyl methacrylate (MMA) as a new thermoplastic copolymer (T-SPI) was prepared. The properties of the material were evaluated with DSC, FT-IR, and rotary rheometry. The results indicated that the monomer was grafted on SPI successfully. The T-SPI had a glass transition at about 66°C. T-SPI was a typical viscoelastic material, and its elastic ratio was 65.27%, the shear viscosity was very sensitive to temperature and the flowability of T-SPI was regulated by temperature.

Class Specific Physical Properties of Liquid Crystals and Correlations with Molecular Structure and Static Electrooptical Performance in Twist Cells

We made measurements of the temperature dependence of the static dielectric constants, the optical anisotropy and the three elastic constants of binary mixtures belonging to twelve structurally and physically markedly different liquid crystal classes. The class-specific material properties were quantitatively correlated with molecular structural elements. The changes of material properties occurring when different LC-classes are combined were investigated. Analytical approximations are presented which are shown to reproduce the static transmission characteristics of twisted nematic cells and their dependence on material constants and temperature with an accuracy comparable to exact numerical calculations. Strong smectic pretransitional effects are shown to influence not only k22 and k33 but also k11, thus suggesting that not only twist and bend but also splay deformations may be prohibitive in smectics. We show that the elastic ratio &33/&11 of different liquid crystal classes increases with increasing dielectric anisotropy thus leading to a decrease of the slope of transmission characteristics of twist cells. Furthermore, it is shown that k33/k11 decreases for molecules comprising heterocyclic rings whereas hydrogenation of an aromatic ring causes k33/k11 to increase.

The Resolution and Contrast in Biological Sections Determined by Inelastic and Elastic Scattering

In the electron microscopy of biological sections the adverse effect of chromatic aberration on image resolution is well known. In this paper calculations are presented for the inelastic and elastic image intensities using a wave-optical formulation. Quantitative estimates of the deterioration in image resolution as a result of chromatic aberration are presented as an alternative to geometric calculations. The predominance of inelastic scattering in the unstained biological and polymeric materials is shown by the inelastic to elastic ratio, I/E, within an objective aperture of 0.005 rad for amorphous carbon of a thickness, t=50nm, typical of biological sections; E=200keV, I/E=16.