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Purpose: To compare optical and visual performances of two one-piece aspherical implanted intraocular lenses (IOLs) following phacoemulsification cataract surgery in a contralateral eye study., Methods: In this prospective randomized parallel-group study, 25 patients with bilateral age-related cataract were implanted in one eye with the EnVista IOL (MX60, Bausch & Lomb Corporations, Rochester, NY, USA) and the Acrysof IQ IOL (Acrysof IQ SN60WF, Alcon Surgical Laboratories, Fort Worth, TX, USA) in the other eye. Uncorrected and corrected distance visual acuity (UDVA, CDVA), refractive status, higher-orders aberrations (HOAs) in 5 and 6 mm pupil size, contrast sensitivity (CS) with and without glare, color vision status, and patient satisfaction were assessed in the two eyes at 1 and 3 months after surgery., Results: There was no significant difference in CDVA (P > 0.99), UDVA (P = 0.46), spherical equivalent refractive error (P = 0.63), CS with and without glare across different spatial frequencies, color vision, and root mean square (RMS) of aberrometric values between the two IOLs after 3-month follow-up. Spherical aberration with 5 and 6 mm pupil sizes (P = 0.02) and horizontal coma with a 6 mm pupil size (P < 0.001) were lower with the EnVista IOL. Patient's satisfaction showed no cases of dissatisfaction, and most patients were highly or moderately satisfied with both IOLs., Conclusion: The visual and optical performance of eyes implanted with the EnVista IOL or the Acrysof IQ IOL was similar, although the aberration profile differed., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V.)

Purpose : To compare the corneal cone location on different maps and instruments, and their agreements, with elevation maps. Methods : In 90 left eyes with bilateral keratoconus, the apex of cone location was determined based on the maximum simulated keratometry (Kmax) location on the anterior sagittal curvature map by Pentacam HR, the maximum curvature on the mean curvature map by ATLAS 9000, most elevated point of the island of positive elevation relative to the best fit sphere on the front and back corneal elevation maps by Pentacam HR, and thinnest point on the thickness map by Pentacam HR and Orbscan, and the thinnest points on pachymetry and epithelial thickness maps by RTVue OCT. Results : There was a significant difference among the location on different maps along the x - and y -axes ( p < .001). The lowest agreement with the cone apex on both front and back elevation maps was for the anterior sagittal curvature map and the highest agreement for the Pentacam thickness map. The majority of keratoconus cone apexes were displaced in the inferotemporal direction on the different maps except for the epithelial thickness maps. Conclusions : Despite the variability between different devices and methods; the thickness map on the Pentacam HR showed the highest correlation with the front and back elevation maps, while the RTVue epithelial thickness map showed the poorest correlation. Based on this study, epithelial thickness maps and anterior curvature maps should be utilized with caution to determine the location of the cone.

Precise protein sequencing and folding are believed to generate the structure and chemical diversity of natural channels 1,2 , both of which are essential to synthetically achieve proton transport performance comparable to that seen in natural systems. Geometrically defined channels have been fabricated using peptides, DNAs, carbon nanotubes, sequence-defined polymers and organic frameworks 3-13 . However, none of these channels rivals the performance observed in their natural counterparts. Here we show that without forming an atomically structured channel, four-monomer-based random heteropolymers (RHPs) 14 can mimic membrane proteins and exhibit selective proton transport across lipid bilayers at a rate similar to those of natural proton channels. Statistical control over the monomer distribution in an RHP leads to segmental heterogeneity in hydrophobicity, which facilitates the insertion of single RHPs into the lipid bilayers. It also results in bilayer-spanning segments containing polar monomers that promote the formation of hydrogen-bonded chains 15,16 for proton transport. Our study demonstrates the importance of the adaptability that is enabled by statistical similarity among RHP chains and of the modularity provided by the chemical diversity of monomers, to achieve uniform behaviour in heterogeneous systems. Our results also validate statistical randomness as an unexplored approach to realize protein-like behaviour at the single-polymer-chain level in a predictable manner.

Here, we present a suitable advancement of parallel local oxidation nanolithography, demonstrating its feasibility in alternate current mode (AC-PLON). For demonstration, we fabricated model structures consisting of an array of parallel nanostripes of electrochemical SiO x with a controlled roughness. Besides, we proved the repeatability of AC-PLON and its integrability with conventional parallel local oxidation nanolithography., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Hybrid biotic abiotic devices can be used to interface electronics with biological systems for novel therapies or to increase device functionality beyond silicon. Many strategies exist to merge the electronic and biological worlds, one dominated by electrons and holes as charge carriers, the other by ions. In the biological world, lipid bilayers and ion channels are essential to compartmentalize the cell machinery and regulate ionic fluxes across the cell membrane. Here, we demonstrate a bioelectronic device in which a lipid bilayer supported on H+-conducting Pd/PdHx contacts contains carbon nanotubes porin (CNTP) channels. This bioelectronic device uses CNTPs to control of H+ flow across the lipid bilayer with a voltage applied to the Pd/PdHx contacts. Potential applications of these devices include local pH sensing and control., Competing Interests: The authors have declared that no competing interests exist.

Merging biological systems with electronic components requires converting biological ionic currents into electrical signals. Previously, we coupled green-light-activated transport of protons by a palladium-binding version of H. turkmenica deltarhodopsin (HtdR) with electronic signal generation by exploiting palladium hydride (PdHx) formation on palladium (Pd) electrodes. Here, we broaden the scope of these devices by showing that blue proteorhodopsin (BPR) from marine bacteria is a suitable proton pump for expanding their spectral range. After engineering BPR for Pd binding and high-level expression in E. coli and after demonstrating that the fused Pd-binding domain is properly oriented to bring exiting protons to the surface of Pd/PdHx contacts, we take advantage of the pH tunability of the BPR absorption spectrum to construct HtdR- and BPR-based devices with light absorption maxima, and thus photocurrent maxima, separated by 37 nm. These devices exhibit wavelength-dependent photocurrent production when illuminated between 450 and 600 nm, opening the door to the development of biological cameras.

Biological systems exchange information often with chemical signals. Here, we demonstrate the chemical delivery of a fluorescent label using a bioelectronic trigger. Acid-sensitive microparticles release fluorescin diacetate upon low pH induced by a bioelectronic device. Cardiac fibroblast cells (CFs) uptake fluorescin diacetate, which transforms into fluorescein and emits a fluorescent signal. This proof-of-concept bioelectronic triggered delivery may be used in the future for real-time programming and control of cells and cell systems.

From cell-to-cell communication to metabolic reactions, ions and protons (H + ) play a central role in many biological processes. Examples of H + in action include oxidative phosphorylation, acid sensitive ion channels, and pH dependent enzymatic reactions. To monitor and control biological reactions in biology and medicine, it is desirable to have electronic devices with ionic and protonic currents. Here, we summarize our latest efforts on bioprotonic devices that monitor and control a current of H + in physiological conditions, and discuss future potential applications. Specifically, we describe the integration of these devices with enzymatic logic gates, bioluminescent reactions, and ion channels.

In biological systems, intercellular communication is mediated by membrane proteins and ion channels that regulate traffic of ions and small molecules across cell membranes. A bioelectronic device with ion channels that control ionic flow across a supported lipid bilayer (SLB) should therefore be ideal for interfacing with biological systems. Here, we demonstrate a biotic-abiotic bioprotonic device with Pd contacts that regulates proton (H + ) flow across an SLB incorporating the ion channels Gramicidin A (gA) and Alamethicin (ALM). We model the device characteristics using the Goldman-Hodgkin-Katz (GHK) solution to the Nernst-Planck equation for transport across the membrane. We derive the permeability for an SLB integrating gA and ALM and demonstrate pH control as a function of applied voltage and membrane permeability. This work opens the door to integrating more complex H + channels at the Pd contact interface to produce responsive biotic-abiotic devices with increased functionality.

Fusion of a palladium-binding peptide to an archaeal rhodopsin promotes intimate integration of the lipid-embedded membrane protein with a palladium hydride protonic contact. Devices fabricated with the palladium-binding deltarhodopsin enable light-activated conversion of protonic currents to electronic currents with on/off responses complete in seconds and a nearly tenfold increase in electrical signal relative to those made with the wild-type protein., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)