Lithiation and Delithiation Reactions of Binary Silicide Electrodes in an Ionic Liquid Electrolyte as Novel Anodes for Lithium‐Ion Batteries

We investigated the lithiation and delithiation properties of pure binary silicide electrodes in an ionic liquid electrolyte as novel anodes for lithium‐ion batteries. Some electrodes maintain a high reversible capacity in the electrolyte, whereas they show a poor cycling performance in an organic electrolyte. The superior performance results from the high affinity for the transition metal that composes the silicide with Li. Based on reaction behavior analysis, the crystal structure of silicide is maintained during the cycling, and phase separation does not occur. The ionic liquid electrolyte suppresses the formation of cracks and exfoliation of the silicide layer from a substrate. In addition, a surface film formed on the silicide electrode through the reductive decomposition of the electrolyte has different components than that on a Si electrode, even in the same ionic liquid electrolyte. Soft X‐ray emission spectroscopy demonstrates that the pure silicide itself reacts with Li. The obtained results will provide significant insights into novel alloy‐based anode materials for lithium‐ion batteries

Intravoxel incoherent motion (IVIM) and non-Gaussian diffusion MRI of the lactating breast

Purpose: To investigate the effect of breastfeeding on IVIM and non-Gaussian diffusion MRI in the breast. Materials and methods: An IRB approved prospective study enrolled seventeen volunteers (12 in lactation and 5 with post-weaning, range 31–43 years; mean 35.4 years). IVIM (fIVIM and D*) and non-Gaussian diffusion (ADC0 and K) parameters using 16 b values, plus synthetic apparent diffusion coefficients (sADCs) from 2 key b values (b = 200 and 1500 s/mm2) were calculated using regions of interest. ADC0 maps of the whole breast were generated and their contrast patterns were evaluated by two independent readers using retroareolar and segmental semi-quantitative scores. To compare the diffusion and IVIM parameters, Wilcoxon signed rank tests were used between pre- and post-breastfeeding and Mann-Whitney tests were used between post-weaning and pre- or post-breastfeeding. Results: ADC0 and sADC values significantly decreased post-breastfeeding (1.90 vs. 1.72 × 10−3 mm2/s, P < 0.001 and 1.39 vs. 1.25 × 10−3 mm2/s, P < 0.001) while K values significantly increased (0.33 vs. 0.44, P < 0.05). fIVIM values significantly increased after breastfeeding (1.97 vs. 2.97%, P < 0.01). No significant difference was found in D* values. There was significant heterogeneity in ADC0 maps post-breastfeeding, both in retroareolar and segmental scores (P < 0.0001 and =0.0001). Conclusion: IVIM and non-Gaussian diffusion parameters significantly changed between pre- and post-breastfeeding status, and care needs to be taken in interpreting diffusion-weighted imaging (DWI) data in lactating breasts. Keywords: Diffusion-weighted imaging, Intravoxel incoherent motion, Kurtosis, Lactation, Breas

Variability of non-Gaussian diffusion MRI and intravoxel incoherent motion (IVIM) measurements in the breast

<div><p>We prospectively examined the variability of non-Gaussian diffusion magnetic resonance imaging (MRI) and intravoxel incoherent motion (IVIM) measurements with different numbers of b-values and excitations in normal breast tissue and breast lesions. Thirteen volunteers and fourteen patients with breast lesions (seven malignant, eight benign; one patient had bilateral lesions) were recruited in this prospective study (approved by the Internal Review Board). Diffusion-weighted MRI was performed with 16 b-values (0–2500 s/mm² with one number of excitations [NEX]) and five b-values (0–2500 s/mm², 3 NEX), using a 3T breast MRI. Intravoxel incoherent motion (flowing blood volume fraction [fIVIM] and pseudodiffusion coefficient [D*]) and non-Gaussian diffusion (theoretical apparent diffusion coefficient [ADC] at <i>b</i> value of 0 sec/mm² [ADC₀] and kurtosis [K]) parameters were estimated from IVIM and Kurtosis models using 16 b-values, and synthetic apparent diffusion coefficient (sADC) values were obtained from two key b-values. The variabilities between and within subjects and between different diffusion acquisition methods were estimated. There were no statistical differences in ADC₀, K, or sADC values between the different b-values or NEX. A good agreement of diffusion parameters was observed between 16 b-values (one NEX), five b-values (one NEX), and five b-values (three NEX) in normal breast tissue or breast lesions. Insufficient agreement was observed for IVIM parameters. There were no statistical differences in the non-Gaussian diffusion MRI estimated values obtained from a different number of b-values or excitations in normal breast tissue or breast lesions. These data suggest that a limited MRI protocol using a few b-values might be relevant in a clinical setting for the estimation of non-Gaussian diffusion MRI parameters in normal breast tissue and breast lesions.</p></div

Visualizing Intramolecular Dynamics of Membrane Proteins

Membrane proteins play important roles in biological functions, with accompanying allosteric structure changes. Understanding intramolecular dynamics helps elucidate catalytic mechanisms and develop new drugs. In contrast to the various technologies for structural analysis, methods for analyzing intramolecular dynamics are limited. Single-molecule measurements using optical microscopy have been widely used for kinetic analysis. Recently, improvements in detectors and image analysis technology have made it possible to use single-molecule determination methods using X-rays and electron beams, such as diffracted X-ray tracking (DXT), X-ray free electron laser (XFEL) imaging, and cryo-electron microscopy (cryo-EM). High-speed atomic force microscopy (HS-AFM) is a scanning probe microscope that can capture the structural dynamics of biomolecules in real time at the single-molecule level. Time-resolved techniques also facilitate an understanding of real-time intramolecular processes during chemical reactions. In this review, recent advances in membrane protein dynamics visualization techniques were presented

Within-subject coefficient of variation (wCV) and <i>P</i> values comparing the normal breast tissue datasets using different combinations of b-values and NEXs.

<p>Within-subject coefficient of variation (wCV) and <i>P</i> values comparing the normal breast tissue datasets using different combinations of b-values and NEXs.</p

Intraclass correlation coefficient of diffusion parameters in malignant and benign breast tumor datasets using one and three number of excitations (NEX) of five b-values.

<p>Intraclass correlation coefficient of diffusion parameters in malignant and benign breast tumor datasets using one and three number of excitations (NEX) of five b-values.</p

Diffusion and perfusion parameters in the datasets of malignant and benign breast tumors.

<p>Diffusion and perfusion parameters in the datasets of malignant and benign breast tumors.</p

DWI and IVIM parametric maps of invasive ductal carcinoma in a 63-year-old woman.

<p>The patient had bilateral lesions involving invasive ductal carcinoma in the left breast and fibroadenoma in the right breast (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0193444#pone.0193444.g001" target="_blank">Fig 1</a>). Axial diffusion and IVIM MRI maps were overlaid on T2-weighted images. (A) T2-weighted image, (B) ADC₀ map, (C) K map, (D) sADC map (E) fIVIM map, (F) D* map.</p