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This paper investigates the factors influencing the career decisions of Chinese college graduates. The study applied the experimental method, with a survey conducted among two groups of college graduates (Chinese and international students). The experiment involved 686 students (343 Chinese students and 343 international students) in their final year. The main criteria for career choices among Chinese students include motivation (76%), interest (62%), personal development (53%), aptitudes (48%), awareness of the profession (38%) and attitudes of their parents/instructors (72%). By contrast, international students chose personal development (81%), aptitudes (74%) and motivation (68%) among the criteria. A career guidance training programme has been developed in order to improve motivation and willingness of college graduates to make decisions about their careers. The practical value and research outlooks are based on the opportunities arising when determining the influence of cross-cultural characteristics on the choice of a profession in the course of exploring the motivation and willingness to make career decisions not just for college graduates but also for universities in China and other countries in a comparative context. [ABSTRACT FROM AUTHOR]

Estimation and inference are two key components toward the solution of any statistical problem; however, the inferential issues of statistical assessment of agreement among two or more raters have not been well developed as compared to the development of estimation procedures in this area. The fundamental reason for this gap is the complex expression of the concordance correlation coefficient (CCC) that is frequently used in assessing agreement among raters. Large sample‐based statistical tests for CCC often fail to produce desired results for small samples. Hence, inferential procedures for small samples are urgently needed to evaluate agreement between raters. We argue that hypothesis testing of CCC has little value in practice due to the absence of a gold standard of agreement. In this article, we construct the generalized confidence interval (GCI) for CCC utilizing a bivariate normal distribution of measurements, and also develop a large sample‐based confidence interval (LSCI). We establish satisfactory performance of GCI by providing the desired coverage probability (CP) via simulation. Results of GCI and LSCI are illustrated and compared with a data set of a recent study performed at U.S. Department of Veterans Affairs, Hines. [ABSTRACT FROM AUTHOR]

In our previous study, Oxysterol-binding protein-related protein 2 (OSBPL2) was first identified as a new deafness-causative gene contribute to non-syndromic hearing loss. However, the underlying mechanism of OSBPL2 -induced hearing loss remains unknown. Here, we used hearing-specific cells and tissues OC-1 cells and zebrafish inner ear tissues as models to identify common transcriptome changes in genes and pathways in the absence of human OSBPL2 orthologues by RNA-seq analysis. In total, 2112 differentially expressed genes (DEGs) were identified between wild-type (WT) and Osbpl2 −/− OC-1 cells, and 877 DEGs were identified between WT and osbpl2b −/- zebrafish inner ear tissues. Functional annotation implicated Osbpl2/osbpl2b in lipid metabolism, cell adhesion and the extracellular matrix in both OC-1 cells and zebrafish inner ear tissues. Protein–protein interaction (PPI) analysis indicated that Osbpl2/osbpl2b were also involved in ubiquitination. Further experiments showed that Osbpl2 −/− OC-1 cells exhibited an abnormal focal adhesion morphology characterized by inhibited FAK activity and impaired cell adhesion. In conclusion, we identified novel pathways modulated by OSBPL2 orthologues, providing new insight into the mechanism of hearing loss induced by OSBPL2 deficiency. • Osbpl2 / osbpl2b defects enrich ECM-receptor interaction and focal adhesion in OC-1 cells and zebrafish inner ear tissues. • The activity of FAK is inhibited in Osbpl2 −/− OC-1 cells. • Novel pathways are identified to be modulated by OSBPL2 orthologues. [ABSTRACT FROM AUTHOR]

Abstract: We have previously reported on the equivalent scatterer size, attenuation coefficient, and axial strain properties of atherosclerotic plaque ex vivo. Since plaque structure and composition may be damaged during a carotid endarterectomy procedure, characterization of in vivo properties of atherosclerotic plaque is essential. The relatively shallow depth of the carotid artery and plaque enables non-invasive evaluation of carotid plaque utilizing high frequency linear-array transducers. We investigate the ability of the attenuation coefficient and equivalent scatterer size parameters to differentiate between calcified, and lipidic plaque tissue. Softer plaques especially lipid rich and those with a thin fibrous cap are more prone to rupture and can be classified as unstable or vulnerable plaque. Preliminary results were obtained from 10 human patients whose carotid artery was scanned in vivo to evaluate atherosclerotic plaque prior to a carotid endarterectomy procedure. Our results indicate that the equivalent scatterer size obtained using Faran’s scattering theory for calcified regions are in the 120–180μm range while softer regions have larger equivalent scatterer size distribution in the 280–470μm range. The attenuation coefficient for calcified regions as expected is significantly higher than that for softer regions. In the frequency bandwidth ranging from 2.5 to 7.5MHz, the attenuation coefficient for calcified regions lies between 1.4 and 2.5dB/cm/MHz, while that for softer regions lies between 0.3 and 1.3dB/cm/MHz. [Copyright &y& Elsevier]

Abstract: Many ultrasonic parameters, primarily related to attenuation and scatterer size, have been used to characterize the composition of atherosclerotic plaque tissue. In this study, we combine elastographic (axial strain ratio) and ultrasonic tissue characterization parameters, namely the attenuation coefficient and a scattering parameter associated with an “equivalent” scatterer size to delineate between fibrous, calcified, and lipidic plaque tissue. We present results obtained from 44 ex vivo atherosclerotic plaque specimens obtained after carotid endarterectomy on human patients. Our results in the frequency range 2.5∼7.5 MHz indicate that softer plaques (with higher values of the strain ratio) are usually associated with larger equivalent scatterer size estimates (200 ∼500 μm) and lower values of the attenuation coefficient slope (<1 dB/cm/MHz). On the other hand, stiffer plaques (with lower strain ratio values) are associated with smaller equivalent scatterer size estimates (100 ∼200 μm) and higher values of the attenuation coefficient slope (1∼3 dB/cm/MHz). These results indicate that ultrasonic tissue characterization and strain parameters have the potential to differentiate between different plaque types. These parameters can be estimated from radio-frequency data acquired under in vivo conditions and may help the clinician decide on appropriate interventional techniques. (E-mail: tvarghese@wisc.edu) [Copyright &y& Elsevier]

Abstract: The cross-correlation algorithm used to compute the local strain components for elastographic imaging requires a minimum radio-frequency data segment length of around 10 wavelengths to obtain accurate and precise strain estimates with a reasonable signal-to-noise ratio. Shorter radio-frequency data segments generally introduce increased estimation errors as the information content in the data segment reduces. However, shorter data segments and increased overlaps are essential to improve the axial resolution in the strain image. In this paper, we propose a two-step cross-correlation technique that enables the use of window lengths on the order of a single wavelength to provide displacement and strain estimates with similar noise properties as those obtained with a 10 wavelength window. The first processing step utilizes a window length on the order of 10 wavelengths to obtain coarse displacement estimates between the pre- and postcompression radio frequency data frames. This coarse displacement is then interpolated and utilized as the initial guess-estimate for the second cross-correlation processing step using the smaller window. This step utilizes a single wavelength window to improve the axial resolution in strain estimation, without significantly compromising the noise properties of the image. Simulation and experimental results show that the signal-to-noise and contrast-to-noise ratio estimates improve significantly at the smaller window lengths with the two-step processing when compared with the use of a similar sized window in the currently utilized single window method. (E-mail: tvarghese@wisc.edu) [Copyright &y& Elsevier]

Abstract: Intravascular ultrasound (US) elastography reveals the elastic properties of vascular tissue and plaque. However, misalignment of the US catheter in the vessel lumen can cause incorrect strain estimation in intravascular US elastography caused by strain projection artifacts. In this paper, we present a general theoretical solution where the impact of catheter eccentricity, tilt and noncoplanar errors on the strain estimates are derived. Appropriate corrections to strain estimates can then be applied with prior knowledge of the catheter position information to reduce the strain projection artifacts. Simulations using a frequency-domain–based algorithm that models intravascular US imaging before and after a specified deformation are presented. The simulations are used to verify the theoretical derivations for two displacement situations (linear and nonlinear) under intraluminal pressure, with and without stress decay. The linear displacement case demonstrates that the correction factor is dependent only on the angle between the US beam and the cross-sectional plane of the vessel. For the nonlinear displacement case, where a l/r stress decay in the displacement is modeled, the correction factor becomes a more complicated function of the azimuthal angle. (E-mail: tvarghese@wisc.edu) [Copyright &y& Elsevier]

Abstract: A set of five tissue-mimicking phantoms with cylindrical inclusions were produced for assessing long-term stability of geometry and elastic properties and assessing accuracy of determination of elastic properties. The base aqueous materials were either gelatin or a mixture of agar and gelatin. Stiffness was controlled by selection of the volume percent consisting of microscopic safflower oil droplets. Cylinder diameters remained unchanged within 1% or 2% over many months. Strain ratios from elastograms of the phantoms were stable over many months, implying that elastic contrasts were also stable. Test samples, called production samples, for measurement of Young’s moduli were made at the time of manufacture of each phantom and were stored separately from one another. Each production sample was homogeneous and consisted of either inclusion material or background material. For all five phantoms, it was found that the elastic contrast computed using Young’s modulus values determined using the production samples accurately represented the true elastic contrasts in the corresponding phantom. This finding was established by the fact that the (true) elastic contrasts determined using samples excised from the phantoms themselves agreed with the elastic contrasts obtained using the homogeneous production samples. (E-mail: elmadsen@wisc.edu) [Copyright &y& Elsevier]

Abstract: Two anthropomorphic uterine phantoms were developed that allow assessment and comparison of strain imaging systems adapted for use with saline-infused sonohysterography (SIS). Tissue-mimicking (TM) materials consist of dispersions of safflower oil in gelatin. TM fibroids are stiffer than the TM myometrium/cervix, and TM polyps are softer. The first uterine phantom has 3-mm-diameter TM fibroids distributed randomly in TM myometrium. The second uterine phantom has a 5-mm and 8-mm spherical TM fibroid, in addition to a 5-mm spherical and a 12.5-mm-long (medicine capsule–shaped) TM endometrial polyp protruding into the endometrial cavity; also, a 10-mm spherical TM fibroid projects from the serosal surface. Strain images using the first phantom show the stiffer 3-mm TM fibroids in the myometrium. Results from the second uterine phantom show that, as expected, parts of inclusions projecting into the uterine cavity will appear very stiff, whether they are stiff or soft. Results from both phantoms show that although there is a five-fold difference in the Young''s moduli values, there is not a significant difference in the strain in the transition from the TM myometrium to the TM fat. These phantoms allow for realistic comparison and evolution of SIS strain imaging techniques and can aid clinical personnel to develop skills for SIS strain imaging. (E-mail: mahobson@gmail.com) [Copyright &y& Elsevier]

Abstract: Two equivalent anthropomorphic breast phantoms were constructed, one for use in ultrasound elastography and the other in magnetic resonance (MR) elastography. A complete description of the manufacturing methods is provided. The materials used were oil-in-gelatin dispersions, where the volume percent oil differentiates the materials, primarily according to Young’s moduli. Values of Young’s moduli are in agreement with in vitro ranges for the corresponding normal and abnormal breast tissues. Ultrasound and nuclear magnetic resonance (NMR) properties are reasonably well represented. Phantoms of the type described promise to aid researchers who are developing hardware and software for elastography. Examples of ultrasound and MR elastograms of the phantoms are included to demonstrate the utility of the phantoms. Also, the level of stability of elastic properties of the component materials is quantified over a 15-month period. Such phantoms can serve as performance-assessing intermediaries between simple phantoms (consisting, for example, of homogeneous cylindrical inclusions in a homogeneous background) and a full-scale clinical trial. Thus, premature clinical trials may be avoided. (E-mail: elmadsen@wisc.edu) [Copyright &y& Elsevier]