Unusual Temperature Dependence of Nanoscale Structural Organization in Deep Eutectic Solvents

In a recent work, we reported the existence of nanoscale spatial organization in (alkylamide + Li⁺/ClO₄^–)-based deep eutectic solvents (DESs). We also described that the nanoscale organization in these systems was primarily due to ion-pair self-segregation. This segregation also accompanied prominent interaction between the ionic species of the electrolyte and alkylamide polar groups. In the present study, we show that for the DESs studied, the intensity of the prepeak, the so-called marker of the nanoscale heterogeneity, in the X-ray and neutron scattering structure functions increases upon increasing temperature. Herein, we show that the increase in the heterogeneity is because of the enhanced correlations between the ionic species at higher temperature. We also show that the rate of enhancement in the ionic correlations with temperature is more than the rate of diminution in the electrolyte–alkylamide cross-correlations. The alkylamide–alkylamide correlations are largely unaffected by any change in the temperature

Controlling Mixed-Protein Adsorption Layers on Colloidal Alumina Particles by Tailoring Carboxyl and Hydroxyl Surface Group Densities

We show that different ratios of bovine serum albumin (BSA) and lysozyme (LSZ) can be achieved in a mixed protein adsorption layer by tailoring the amounts of carboxyl (−COOH) and aluminum hydroxyl (AlOH) groups on colloidal alumina particles (<i>d</i>₅₀ ≈ 180 nm). The particles are surface-functionalized with −COOH groups, and the resultant surface chemistry, including the remaining AlOH groups, is characterized and quantified using elemental analysis, ζ potential measurements, acid–base titration, IR spectroscopy, electron microscopy, nitrogen adsorption, and dynamic light scattering. BSA and LSZ are subsequently added to the particle suspensions, and protein adsorption is monitored by in situ ζ potential measurements while being quantified by UV spectroscopy and gel electrophoresis. A comparison of single-component and sequential protein adsorption reveals that BSA and LSZ have specific adsorption sites: BSA adsorbs primarily via AlOH groups, whereas LSZ adsorbs only via −COOH groups (1–2 −COOH groups on the particle surface is enough to bind one LSZ molecule). Tailoring such groups on the particle surface allows control of the composition of a mixed BSA and LSZ adsorption layer. The results provide further insight into how particle surface chemistry affects the composition of protein adsorption layers on colloidal particles and is valuable for the design of such particles for biotechnological and biomedical applications

Engineering Enhanced Pore Sizes Using FhuA Δ1-160 from E. coli Outer Membrane as Template

<p>Mean AD for ten major white matter tracts in healthy term controls (blue bars) and ELBW infants (red bars).</p

Mean total number of fibers with corresponding <i>intra</i>-rater measurement error, repeatability coefficient, and reliability data for ten white matter tracts in preterm and term infants.

<p>Mean total number of fibers with corresponding <i>intra</i>-rater measurement error, repeatability coefficient, and reliability data for ten white matter tracts in preterm and term infants.</p

Location of ROIs on DTI color maps for the uncinate (UNC) tract in a preterm infant.

<p>(A) First polygonal shaped ROI drawn for segmenting the UCN in coronal view; (B) Fiber bundle after the first ROI was drawn in sagittal view; (C) The second ROI drawn anterior to the first ROI on the same coronal image; (D) Final trajectory of the UNC in sagittal view.</p

<i>Intra</i>-rater and <i>inter</i>-rater Dice similarity index for total number of voxels of ten white matter tracts in preterm and term infants.

<p><i>Intra</i>-rater and <i>inter</i>-rater Dice similarity index for total number of voxels of ten white matter tracts in preterm and term infants.</p

Reliability and Repeatability of Quantitative Tractography Methods for Mapping Structural White Matter Connectivity in Preterm and Term Infants at Term-Equivalent Age

<div><p>Premature infants exhibit widespread insults and delays in white matter maturation that can be sensitively detected early using diffusion tensor imaging. Diffusion tensor tractography facilitates in vivo visualization of white matter tracts and has the potential to be more sensitive than simpler two-dimensional DTI-based measures. However, the reliability and reproducibility of performing tractography for major white matter tracts in preterm infants is not known. The main objective of our study was to develop highly reliable and repeatable methods for ten white matter tracts in extremely low birth weight infants (birth weight ≤1000 g) at term-equivalent age. To demonstrate clinical utility, we also compared fiber microstructural and macrostructural parameters between preterm and healthy term controls. Twenty-nine ELBW infants and a control group of 15 healthy term newborns were studied. A team of researchers experienced in neuroanatomy/neuroimaging established the manual segmentation protocol based on a priori anatomical knowledge and an extensive training period to identify sources of variability. Intra- and inter-rater reliability and repeatability was tested using intra-class correlation coefficient, within-subject standard deviation (SD), repeatability, and Dice similarity index. Our results support our primary goal of developing highly reliable and reproducible comprehensive methods for manual segmentation of 10 white matter tracts in ELBW infants. The within-subject SD was within 1–2% and repeatability within 3–7% of the mean values for all 10 tracts. The intra-rater Dice index was excellent with a range of 0.97 to 0.99, and as expected, the inter-rater Dice index was lower (range: 0.80 to 0.91), but still within a very good reliability range. ELBW infants exhibited fewer fiber numbers and/or abnormal microstructure in a majority of the ten quantified tracts, consistent with injury/delayed development. This protocol could serve as a valuable tool for prompt evaluation of the impact of neuroprotective therapies and as a prognostic biomarker for neurodevelopmental impairments.</p></div

Mean number of voxels for ten major white matter tracts in healthy term controls (blue bars) and ELBW infants (red bars).

<p>Mean number of voxels for ten major white matter tracts in healthy term controls (blue bars) and ELBW infants (red bars).</p

<i>Inter</i>-rater measurement error, repeatability coefficient, and reliability data for mean fractional anisotropy of ten white matter tracts in preterm and term infants.

<p><i>Inter</i>-rater measurement error, repeatability coefficient, and reliability data for mean fractional anisotropy of ten white matter tracts in preterm and term infants.</p

Location of ROIs on DTI color maps for the optic radiation (OR) in a preterm infant brain.

<p>(A) First ROI over the lateral geniculate (LGN) region in sagittal view; (B) Fibers after the placement of the first ROI in sagittal view; (C) Second polygonal shaped ROI around the sagittal stratum fibers in coronal view; (D) Third oval shaped ROI drawn at the anterior edge of the occipital lobe in sagittal view; (E&F) 3D Sagittal and axial images showing the final trajectory of the OR tract.</p