Greernguyen3097

Data-driven modeling directly utilizes experimental data with machine learning techniques to predict a material's response without the necessity of using phenomenological constitutive models. Although data-driven modeling presents a promising new approach, it has yet to be extended to the modeling of large-deformation biological tissues. Herein, we extend our recent local convexity data-driven (LCDD) framework (He and Chen, 2020) to model the mechanical response of a porcine heart mitral valve posterior leaflet. The predictability of the LCDD framework by using various combinations of biaxial and pure shear training protocols are investigated, and its effectiveness is compared with a full structural, phenomenological model modified from Zhang et al. (2016) and a continuum phenomenological Fung-type model (Tong and Fung, 1976). We show that the predictivity of the proposed LCDD nonlinear solver is generally less sensitive to the type of loading protocols (biaxial and pure shear) used in the data set, while more sensitive to the insufficient coverage of the experimental data when compared to the predictivity of the two selected phenomenological models. While no pre-defined functional form in the material model is necessary in LCDD, this study reinstates the importance of having sufficiently rich data coverage in the date-driven and machine learning type of approaches. It is also shown that the proposed LCDD method is an enhancement over the earlier distance-minimization data-driven (DMDD) against noisy data. This study demonstrates that when sufficient data is available, data-driven computing can be an alternative method for modeling complex biological materials.Springy poles are a unique load-carrying tool and inspire novel designs of other load-carrying systems. Previous experiments have shown that highly compliant poles with a natural frequency lower than step frequency are more economical than rigid poles during load carriage in walking and this was successfully explained in later modeling studies. However, an energetic benefit was not observed during running with highly compliant poles. We speculate that gait type (running versus walking) may be a factor accounting for the different observations. An optimization-based biped model is adopted to predict the energy cost of load carriage with poles during running, with the parameters from previous experimental studies. The predicted load motion and load-body interaction force agree well with experimental measurements. Compared to running with rigid poles, the highly compliant pole results in reduced peak ground reaction force, longer stance phase duration, and higher energy cost. The changes in running energetics are further found to depend on the natural frequency of the load-pole system relative to the step frequency, but with an opposite trend compared to the changes in walking energetics during pole carriage. Highly compliant poles cost more energy than rigid poles during running, while stiffer poles with a higher natural frequency may offer energetic benefits. This study indicates that the fundamental difference in gait type has a profound influence on the energetic performance of load-carrying devices and this should be taken into consideration in future device designs.Inertial measurement unit systems (IMU) are increasingly used in sports. However, no algorithm evaluating the instantaneous swimming velocity has been validated on the four swimming strokes, or on dive start. Our objective is to develop and validate a new method to measure instantaneous swimming velocity on athletes presenting various musculoskeletal and neurological impairments and swimming one of the four swimming strokes. Seven Paralympic athletes were involved and performed a total of 18 trials of 50 m in real conditions. All trials were recorded with a 3-axis accelerometer, a tethered device and a video camera. TAK-875 cell line The instantaneous velocity was computed by drift-free integration of the forward acceleration. For all trials, Bland-Altman analyses showed a bias of 0.03-0.06 m.s-1 with the tethered device, with 95% LOA lower than 0.31-0.80 m.s-1, RMSE was 0.14-0.39 m.s-1, and ICC amounted 0.494-0.941. No significant difference was found for the mean 50 m velocities between the accelerometer, the tethered device and the video camera. The results obtained for freestyle were comparable to those obtained with GPS in outdoor pools. Those obtained for backstroke, breaststroke and butterfly were very encouraging. Our method is simple, reliable, advantageous compared to tethered devices, and could be easily used in the field by coaches.

With the long-term goal of developing a diagnostic (

Tc) and therapeutic (

Re) agent pair for targeting somatostatin receptor (SSTR)-positive neuroendocrine tumors (NETs), we developed novel metal-cyclized peptides through direct labeling of the potent SSTR2 antagonist Ac-4-NO

-Phe-c(DCys-Tyr-DTrp-Lys-Thr-Cys)-DTyr-NH

(1) with Re (in Re-1),

Tc (in [

Tc]Tc-1) and

Re (in [

Re]Re-1).

Re-1 was characterized by LC-ESI-MS and HR-ESI-MS and was tested for receptor affinity in SSTR-expressing cells (AR42J). Radiolabeling of the peptide was achieved via ligand exchange from

Tc-labeled glucoheptonate or [

Re]ReOCl

(PPh

)

, yielding [

Tc]Tc-1 or [

Re]Re-1, respectively. In vitro stability of [

Tc]Tc-1/[

Re]Re-1 in PBS (10mM) at pH7.4 and 37°C was determined by HPLC analysis. Moreover, [

Tc]Tc-1 stability was tested in cysteine (1mM) and rat serum under the same conditions.

Re-1 consisted of two isomers, confirmed by LC-ESI-MS, with good SSTR2 affinity (IC

=43±6nM). Optimization of the

Tc l complex showed promising in vitro properties, and future in vivo studies will determine the potential for translating such a design into the human clinic.

MicroRNA-325-3p (miR-325-3p) is involved in the progression of a great number of tumors. However, the regulatory mechanism of miR-325-3p on hepatocellular carcinoma (HCC) remains unclear.

In this paper, we aim to investigate the underlying mechanism by which miR-325-3p regulate the progression of HCC.

RT-qPCR was performed to detect the levels of miR-325-3p, CXCL17, and CXCR8. Western bolt was conducted to determine the levels of pro-angiogenic factors VEGF, FGF2, Ang-1 and PDGF-B. Immunohistochemistry was carried to detect the distribution and expression of Ki-67 and CD34 in HCC tissues. MTT and colony formation were carried to evaluate cell proliferation, endothelial tube-formation assay was used detect tubule formation, and transwell assay was performed to evaluate cell migration and invasion ability. Dual-luciferase activity assay was used to verify the relationship between miR-325-3p and CXCL17.

MiR-325-3p was down-regulated in HCC cells and tissues, miR-325-3p overexpression inhibited the proliferation, migration and invasion of HCC cells.