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Following insertion of either Healon (sodium hyaluronate) or Viscoat (sodium chondroitin sulfate-sodium hyaluronate) into the anterior chamber of human eye bank eyes, a controlled amount of small air bubbles was introduced into the anterior chamber during phacoemulsification. After vital staining, damage to endothelial cells in the central cornea was quantified. Endothelial damage averaged 4.5% in eyes in which no viscoelastic was used (positive control), whereas damage was only 0.4% (P less than .001) in eyes in which a viscoelastic was inserted but no air bubbles were introduced (negative control). Endothelial damage in test specimens using air plus Healon averaged 4.9%. Damage in test specimens using air plus Viscoat averaged 0.3% (P less than .02). As demonstrated by scanning electron microscopy, many areas in the positive controls and in the Healon test specimens were damaged too extensively to quantitate accurately by the method we used. Thus, Viscoat may prevent or lessen damage to the corneal endothelium by small air bubbles during phacoemulsification.

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While grid-scale electricity storage (hereafter 'storage') could be crucial for deeply decarbonizing the electric power system, it would increase carbon dioxide (CO 2 ) emissions in current systems across the United States. To better understand how storage transitions from increasing to decreasing system CO 2 emissions, we quantify the effect of storage on operational CO 2 emissions as a power system decarbonizes under a moderate and strong CO 2 emission reduction target through 2045. Under each target, we compare the effect of storage on CO 2 emissions when storage participates in only energy, only reserve, and energy and reserve markets. We conduct our study in the Electricity Reliability Council of Texas (ERCOT) system and use a capacity expansion model to forecast generator fleet changes and a unit commitment and economic dispatch model to quantify system CO 2 emissions with and without storage. We find that storage would increase CO 2 emissions in the current ERCOT system, but would decrease CO 2 emissions in 2025 through 2045 under both decarbonization targets. Storage reduces CO 2 emissions primarily by enabling gas-fired generation to displace coal-fired generation, but also by reducing wind and solar curtailment. We further find that the market in which storage participates drives large differences in the magnitude, but not the direction, of the effect of storage on CO 2 emissions.

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Climate change will likely impact wind and solar resources. As power systems increasingly shift towards wind and solar power, these resource changes will increasingly impact power system operations. We assess how power system operations will be affected by climate change impacts on wind and solar resources by generating wind and solar generation profiles for a reference period and five climate change projections. We then run a unit commitment and economic dispatch model to dispatch a highrenewable generator fleet with these profiles. For climate change projections, we use 2041-2050 output from five global climate models (GCMs) for Representative Concentration Pathway 8.5 for Texas, our study system. All five GCMs indicate increased wind generation potential by 1%-4% under climate change in Texas, while three and two GCMs indicate increased and decreased solar generation potential, respectively, by up to 1%. Uneven generation potential changes across time result in greater changes in dispatched generation by fuel type. Notably, nuclear generation decreases across GCMs by up to 7%, largely in low-demand (winter) months when nuclear plants, which have a high minimum stable load, must reduce their generation to avoid overgeneration. Increased wind and/or solar generation result in reduced system CO 2 emissions and electricity production costs across four of the five GCMs by 8-16 million tons and $216-516 million, or by 2% and 1%, respectively. Future research should assess the atmospheric and climate dynamics that underlie such changes in power system operations.

A series of explanted intraocular lenses (IOLs) and autopsy globes containing IOLs that had previously had Nd:YAG laser posterior capsulotomy were analyzed at the Intermountain Ocular Research Center. A broad spectrum of laser-induced IOL damage was found. In the majority of instances, the damage was classified as mild and consisted of tiny pits on the IOLs' posterior surface. These pits would not be expected to produce any visually significant consequences. Moderate damage consisted of larger, more extensive pitting, craters, and small cracks. The most severely damaged IOLs showed extensive cracking and focal fracturing of the optic. Extensive damage may result in unacceptable visual blurring, distortion, and glare which in extreme cases may warrant IOL explantation, as presented in a case report.