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1. Effect of Assistance Using a Bilateral Robotic Knee Exoskeleton on Tibiofemoral Force Using a Neuromuscular Model

   https://doi.org/10.1007/s10439-022-02950-z  

   McLain, Bailey J. ; Lee, Dawit ; Mulrine, Sierra C. ; Young, Aaron J. ( June 2022 , Annals of Biomedical Engineering)

   Tibiofemoral compression forces present during locomotion can result in high stress and risk damage to the knee. Powered assistance using a knee exoskeleton may reduce the knee load by reducing the work required by the muscles. However, the exact effect of assistance on the tibiofemoral force is unknown. The goal of this study was to investigate the effect of knee extension assistance during the early stance phase on the tibiofemoral force. Nine able-bodied adults walked on an inclined treadmill with a bilateral knee exoskeleton with assistance and with no assistance. Using an EMG-informed neuromusculoskeletal model, muscle forces were estimated, then utilized to estimate the tibiofemoral contact force. Results showed a 28% reduction in the knee moment, which resulted in approximately a 15% decrease in knee extensor muscle activation and a 20% reduction in subsequent muscle force, leading to a significant 10% reduction in peak and 9% reduction in average tibiofemoral contact force during the early stance phase (p < 0.05). The results indicate the tibiofemoral force is highly dependent on the knee kinetics and quadricep muscle activation due to their influence on knee extensor muscle forces, the primary contributor to the knee load. 

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2. Analysis of vitamin B 12 in seawater and marine sediment porewater using ELISA: Vitamin B 12 analysis in seawater using ELISA

   https://doi.org/10.4319/lom.2011.9.515  

   Zhu, Qingzhi ; Aller, Robert C. ; Kaushik, Aleya ( October 2011 , Limnology and Oceanography: Methods)
3. Removing Antenna Effects using an Invertible Neural Network for Improved Estimation of Multilayered Tissue Profiles using UWB Radar

   https://doi.org/10.23919/USNC-URSI54200.2023.10289171  

   Chang, Yuyi ; Sugavanam, Nithin ; Ertin, Emre ( July 2023 , Proceedings of 2023 IEEE USNC-URSI Radio Science Meeting)

   Ultrawideband (UWB) radar sensors are an emerging biosensing modality that can be used to assess the dielectric properties of internal tissues. Antenna effects, including antenna body interactions limit the sensors ability to isolate the weak returns from the internal tissues. In this paper we develop a data driven calibration method for recovering Green’s function of the multilayered media model of the tissue profiles using an Invertible Neural Network (INN). The proposed INN structure is trained to invert the antenna transfer function to form estimates of the Green’s function modeling returns from internal tissues. We use simulation experiments to assess the effectiveness of the trained INN in antenna transfer function inversion. 

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4. Alignment of collagen matrices using magnetic nanowires and magnetic barcode readout using first order reversal curves (FORC) (invited)

   https://doi.org/10.1016/j.jmmm.2017.11.035  

   Sharma, Anirudh ; DiVito, Michael D. ; Shore, Daniel E. ; Block, Andrew D. ; Pollock, Katie ; Solheid, Peter ; Feinberg, Joshua M. ; Modiano, Jaime ; Lam, Cornelius H. ; Hubel, Allison ; et al ( August 2018 , Journal of Magnetism and Magnetic Materials)
5. Using LAMMPS to shed light on Haven’s ratio: Calculation of Haven’s ratio in alkali silicate glasses using molecular dynamics

   https://doi.org/10.3389/fmats.2023.1123213  

   Salrin, Tyler C. ; Johnson, Logan ; White, Seth ; Kilpatrick, Gregory ; Weber, Ethan ; Bragatto, Caio ( February 2023 , Frontiers in Materials)

   Haven and Verkerk studied the diffusion of ions in ionic conductive glasses with and without an external electric field to better understand the mechanisms behind ionic conductivity. In their work, they introduced the concept now known as Haven’s ratio (H R ), which is defined as the ratio of the tracer diffusion coefficient (D self ) of ions to the diffusion coefficient from steady-state ionic conductivity (D σ ), calculated by the Nernst–Einstein equation. D σ can be challenging to obtain experimentally because the number of charge carriers has to be implied, a subject still under discussion in the literature. Molecular dynamics (MD) allows for direct measurement of the mean squared displacement ( r 2 ) of diffusing cations, which can be used to calculate D, avoiding the definition of a charge carrier. Using MD, the authors have calculated the r 2 of three alkali ions (Li, Na, and K) at different temperatures and concentrations in silicate glass, with and without the influence of an electric field. Results found for H R generally fell close to 0.6 at lower concentrations (x = 0.1) and close to 0.3 at higher concentrations (x = 0.2 and 0.3), comparable to the literature, implying that the electric field introduces new mechanisms for the diffusion of ions and that MD can be a powerful tool to study ionic diffusion in glasses under external electric fields. 

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