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Background: To describe the refractive outcomes of eyes with high regular corneal astigmatism undergoing age-related cataract surgery. Methods: Astigmatic patients who underwent cataract surgery with implantation of high-power XY1AT HOYA® toric lenses (IOLs) (≥ T5) between March 2020 and June 2022 were included. Patients were divided into 2 groups based on the type of Total Corneal Astigmatism (TCA) used for the toric IOL calculation: group 1 = TCATK− 700 (TCA measured by the Iol Master 700®) and group 2 = TCAAK− 700 (TCA estimated from the anterior keratometry of the Iol Master 700® and using the Abulafia-Koch regression). The best-uncorrected (UDVA) and corrected (CDVA) distance visual acuity, subjective spherical equivalent (SSEq) and subjective residual cylinder (SRC) were assessed at 1 month. The predictability (centroid [CEPA] and mean absolute error in predicted astigmatism [MAEPA]) of the 2 TCA assessment methods was analyzed. Results: 96 eyes of 74 patients were included. In the whole cohort, the UDVA was 0.14 ± 0.19 logMAR, the CDVA was 0.04 ± 0.07 logMAR. Postoperative SSEq was − 0.24 ± 0.53D. Postoperative SRC was − 0.48 ± 0.56D. The UDVA, SSEq and SRC did not significantly differ between groups. The MAEPA was significantly better with TCAAK−700 compared to TCATK−700: 0.58 ± 0.52D versus 0.65 ± 0.55D (p = 0.01). No significant difference was observed for the CEPA (p(x) = 0.09, p(y) = 0.19). Conclusions: XY1AT HOYA® toric IOLs are a very good alternative even in case of high toricity. Residual astigmatism predictability is high, it would be better with TCAAK− 700. This data should be confirmed with a larger sample of patients. Key messages: What is known: • Toric intraocular lenses allow achieving a significant gain in UCVA in astigmatic patients. • The value of anterior corneal astigmatism correlates with that of posterior corneal astigmatism. What is new: • Residual astigmatism in eyes with high astigmatism implanted with the Vivinex® toric intraocular lens is comparable to that of eyes with intermediate astigmatism using the current digital alignment technology. • The use of the Abulafia-Koch regression allows achieving a greater predictability of postoperative refractive outcomes with the Vivinex intraocular lens compared to the direct measurement of total astigmatism using the Swept-Source OCT technology in high-toricity cases. [ABSTRACT FROM AUTHOR]

The increasing deployment of large-scale wind turbines in place of conventional generators is expected to lead to the dominance of asynchronous power sources in future power systems, further accelerating the trend toward grid electrification. As a result, the ability of power sources to support system voltage and frequency is gradually diminishing. Synchronous condensers (SCs), which are synchronous machines operating without prime movers, serve as effective devices for providing both dynamic voltage support and inertia. They can significantly enhance the system's capacity to maintain voltage and frequency stability. However, most existing studies on the optimization of synchronous condenser configurations tend to focus on only one aspect at a time rather than addressing both simultaneously, limiting the full potential of these devices. Optimizing either the voltage or frequency in isolation often results in suboptimal improvements in the other. Moreover, the simultaneous optimization of both voltage and frequency can lead to non-convergent outcomes, complicating the search for an optimal solution. To address this, the paper proposes a hierarchical optimization strategy for synchronous condenser configuration aimed at enhancing both voltage and frequency stability. First, the connection sites for the synchronous condensers are determined based on short-circuit ratio (SCR) constraints. Next, an outer layer optimization model is developed to minimize the total installed capacity of the condensers while taking into account the SCR and transient overvoltage levels as constraints. Following this, an inner layer optimization model is introduced, incorporating a rate of change in the frequency f R o C o F and maximum frequency deviation f n a d i r as constraints. The model is solved using the bacterial foraging optimization algorithm (BFOA). Finally, a case study of a power grid with a high proportion of wind power validates the effectiveness of the proposed synchronous condenser configuration strategy. Compared to traditional methods, the total required capacity of synchronous condensers was significantly reduced. [ABSTRACT FROM AUTHOR]

This paper reviews recent works related to applications of reinforcement learning in power system optimal control problems. Based on an extensive analysis of works in the recent literature, we attempt to better understand the gap between reinforcement learning methods that rely on complete or incomplete information about the model dynamics and data-driven reinforcement learning approaches. More specifically we ask how such models change based on the application or the algorithm, what the currently open theoretical and numerical challenges are in each of the leading applications, and which reinforcement-based control strategies will rise in the following years. The reviewed research works are divided into "model-based" methods and "model-free" methods in order to highlight the current developments and trends within each of these two groups. The optimal control problems reviewed are energy markets, grid stability and control, energy management in buildings, electrical vehicles, and energy storage. [ABSTRACT FROM AUTHOR]

This paper presents the implementation of an improved resonance-type FCL, designed to enhance the transient stability of a photovoltaic farm. This FCL overcomes the well-known drawbacks associated with the conventional resonance-based FCLs. This FCL limits the fault during the fault period, quickly achieves stability during the recovery period, independent of the reactor's charging state, and notably reduces DC-link voltage fluctuations during faults. A power system simulation setup comprising a PV farm, synchronous generator, transformers, circuit breakers, transmission system, and several branches of loads is used for testing the proposed FCL. The simulation results validate that the proposed FCL better improves the system's stability and leads to improved fault current, PCC voltage, active power, reactive power, and DC-link voltage compared to other common types of resonant FCLs. [ABSTRACT FROM AUTHOR]

Background: The main drawback of BRAF/MEK inhibitors (BRAF/MEKi)-based targeted therapy in the management of BRAF-mutated cutaneous metastatic melanoma (MM) is the development of therapeutic resistance. We aimed to assess in this context the role of mTORC2, a signaling complex defined by the presence of the essential RICTOR subunit, regarded as an oncogenic driver in several tumor types, including MM. Methods: After analyzing The Cancer Genome Atlas MM patients' database to explore both overall survival and molecular signatures as a function of intra-tumor RICTOR levels, we investigated the effects of RICTOR downregulation in BRAFV600E MM cell lines on their response to BRAF/MEKi. We performed proteomic screening to identify proteins modulated by changes in RICTOR expression, and Seahorse analysis to evaluate the effects of RICTOR depletion on mitochondrial respiration. The combination of BRAFi with drugs targeting proteins and processes emerged in the proteomic screening was carried out on RICTOR-deficient cells in vitro and in a xenograft setting in vivo. Results: Low RICTOR levels in BRAF-mutated MM correlate with a worse clinical outcome. Gene Set Enrichment Analysis of low-RICTOR tumors display gene signatures suggestive of activation of the mitochondrial Electron Transport Chain (ETC) energy production. RICTOR-deficient BRAFV600E cells are intrinsically tolerant to BRAF/MEKi and anticipate the onset of resistance to BRAFi upon prolonged drug exposure. Moreover, in drug-naïve cells we observed a decline in RICTOR expression shortly after BRAFi exposure. In RICTOR-depleted cells, both mitochondrial respiration and expression of nicotinamide phosphoribosyltransferase (NAMPT) are enhanced, and their pharmacological inhibition restores sensitivity to BRAFi. Conclusions: Our work unveils an unforeseen tumor-suppressing role for mTORC2 in the early adaptation phase of BRAFV600E melanoma cells to targeted therapy and identifies the NAMPT-ETC axis as a potential therapeutic vulnerability of low RICTOR tumors. Importantly, our findings indicate that the evaluation of intra-tumor RICTOR levels has a prognostic value in metastatic melanoma and may help to guide therapeutic strategies in a personalized manner. [ABSTRACT FROM AUTHOR]

Background: To describe and analyze the real-life refractive, functional and safety outcomes of the Clareon® intraocular lens (IOL) after 3 years. Methods: Data was collected retrospectively for observational purposes between July 2017 and December 2019 in the ophthalmology department of Desgenettes military hospital in Lyon, France. Eyes that underwent cataract surgery with Claeron® implantation were consecutively included. Patients with a systemic or ocular condition that could affect the visual outcome were excluded. Postoperative corrected (CDVA) and uncorrected (UDVA) distance visual acuities as well as capsule and IOL transparency were assessed at 1 month and 3 years. Results: A total of 326 eyes were analyzed at one month and 191 eyes were reassessed at the 3-year follow-up visit. At 3 years, the mean CDVA was 0.003 LogMAR (95% confidence interval [CI]: -0.003 to -0.01) and the mean UDVA was 0.075 (95% CI: 0.054 to 0.095). Three quarters of the patients had an UDVA ≥ 0.097 logMAR (20/25 Snellen equivalent) and 50% had an UDVA ≥ 0 (20/20). The absence of glistening was reported in 95.3% of cases and 4.7% [9] of patients experienced a clinically significant posterior capsular opacification (PCO) for which Nd:YAG treatment was required. Conclusions: This real-life study reports high-performance and stable long-term refractive outcomes of the Clareon® IOL with good safety in terms of PCO and glistening. Key message: What is known The Clareon® is a recent hydrophobic intraocular lens (IOL) that has shown high-performance functional and safety outcomes in published studies after a 1-year follow-up. What is new These good functional and safety outcomes were maintained over a 3-year follow-up. A low rate of Nd:YAG treatment was reported (4.7%), and it was needed late during the third year following surgery. This finding is comparable with what has been reported with the AcrySof material. A low rate of glistening over time was confirmed. [ABSTRACT FROM AUTHOR]

Introduction: The aim of the study was to assess the outcome of long treat-and-extend (TE) anti-VEGF intravitreal injection (IVI) intervals (≥every 12 weeks [Q12W]) in neovascular age-related macular degeneration (nAMD). The aims of this retrospective study were to determine the proportion of nAMD eyes treated ≥ Q12W, to analyze their longitudinal, functional, and anatomical outcomes, and to compare functional and anatomical outcomes between eyes that rapidly versus slowly reached a Q12W regimen and between eyes directly treated with versus initiating lately the TE regimen. Methods: All patients receiving IVIs for nAMD were screened. The longitudinal, functional, and anatomical characteristics of Q12W-treated eyes were reported at different timepoints. Results: Ninety-one eyes were included (38% of our total nAMD cohort). The mean TE regimen time to reach a Q12W interval was 20.1 ± 16.2 months. During this time, a mean number of 12.1 ± 9.3 IVIs were needed. The mean best-corrected visual acuity was 68 letters at the time of diagnosis and was maintained (p > 0.05). Eyes that rapidly reached a Q12W interval had a shorter follow-up before TE regimen initiation (p = 0.04) and received fewer IVIs (p = 0.02) than eyes that slowly reached a Q12W interval. Eyes directly treated with the TE regimen reached a Q12W interval more rapidly than eyes with late TE initiation. The neovascularization subtype was not a predictor of outcome in TE-treated eyes. Conclusion: ≥Q12W eyes represent an important part of the nAMD population in our real-life study. No baseline anatomical characteristics were associated with the outcome under a TE regimen, although early TE regimen initiation allowed extending more rapidly the IVI interval. [ABSTRACT FROM AUTHOR]

Many quantum device signals are proportional to the number of the participating atoms that take part in the detection devices. Among these are optical magnetometers, atomic clocks, quantum communications and atom interferometers. One way to enhance the signal-to-noise ratio is to introduce atom entanglement that increases the signal in a super-radiant-like effect. A coherent em field inside a laser cavity is suggested to achieve atoms' correlation/entanglement. This may also play an important role in the basic quantum arena of many-body physics. An initial novel experiment to test the realization of atoms' correlation is described here. A Cs optical magnetometer is used as a tool to test the operation of a cell-in-cavity laser and its characteristics. A vapor cell is inserted into an elongated external cavity of the pump laser in Littrow configuration. Higher atom polarization and reduced laser linewidth are obtained leading to better magnetometer sensitivity and signal-to-noise ratio. The Larmor frequency changes of the Free Induction Decay of optically pumped Cs atomic polarization in the ambient earth magnetic field at room temperature is measured. Temporal changes in the magnetic field of less than 10 pT/√Hz are measured. The first-order dependence of the magnetic field on temperature and temperature gradients is eliminated, important in many practical applications. Single and gradiometric magnetometer configurations are presented. [ABSTRACT FROM AUTHOR]

The response of a spin exchange relaxation free atomic magnetometer to a repetitive short-pulsed pump was investigated. Quantum sub-resonances at a repetition rate of 1/n of the Larmor frequency of the magnetic field inside the shield are experimentally observed and theoretically explained. This is a type of synchronization phenomenon. Investigations in single alkali atom cells and mixed alkali atoms of K and Rb are presented. In the latter, one species is pumped while the probe is on the other species polarized by spin exchange. The effect of spin destruction, spin exchange, and collisions is studied in order to account for the width of the resonances. Quantum calculations of a three-level Λ model for this phenomenon exhibit a dip at the resonance frequency in the absorption spectrum for both cases of pulsed and cw pump modes and an evidence for electromagnetically induced transparency. [ABSTRACT FROM AUTHOR]

Background: The application of motor learning (ML) principles and research in physical therapy can optimize patient outcomes. However, the translation of the accumulated knowledge in ML to clinical practice is limited. Knowledge translation interventions, which are designed to promote changes in clinical behaviors, have the potential to address this implementation gap. We developed, implemented, and evaluated a knowledge translation intervention for ML implementation that focuses on building clinical capacity among physical therapists for the systematic application of ML knowledge in clinical practice. Methods: A total of 111 physical therapists underwent the intervention, which consisted of the following: (1) an interactive didactic 20-hour course; (2) an illustrated conceptual model of ML elements; and (3) a structured clinical-thinking form. Participants completed the Physical Therapists' Perceptions of Motor Learning (PTP-ML) questionnaire pre and post intervention. The PTP-ML was used to assess ML-related self-efficacy and implementation. Participants also provided post-intervention feedback. A sub-sample (n = 25) provided follow-up feedback more than a year after the completion of the intervention. Pre–post and post-follow-up changes in the PTP-ML scores were calculated. The information gathered from the open-ended items of the post-intervention feedback was analyzed to identify emerging themes. Results: Comparing pre- and post-intervention scores, significant changes were found in the total questionnaire scores, self-efficacy subscale scores, reported implementation subscale scores (P <.0001), and general perceptions and work environment subscale score (P <.005). The mean changes in the total questionnaire and self-efficacy scores also significantly exceeded the Reliable Change Index. In the follow-up sample, these changes were maintained. Participants felt that the intervention helped them organize their knowledge in a structured manner and consciously link their practice elements to concepts in ML. Discussion of clinical cases was reported to be the most valuable educational method, and the illustrated conceptual model of ML elements was the least valued. Respondents also suggested support activities to maintain and enhance the learning experience, including on-site mentorship and hands-on experience. Conclusions: Findings support the positive effect of an educational tool, most prominently on physical therapists' ML self-efficacy. The addition of practical modeling or ongoing educational support may enhance intervention effects. [ABSTRACT FROM AUTHOR]

Purpose: To compare the impact of total corneal astigmatism (TCA) estimated with the Abulafia-Koch formula (TCAABU) versus measured by Total Keratometry (TK), swept-source optical coherence tomography (OCT) coupled with telecentric keratometry (TCATK) on the refractive outcomes after cataract surgery with toric intraocular lens (IOL) implantation. Methods: Two hundred one eyes of 146 patients who underwent cataract surgery with toric IOL implantation (XY1AT; HOYA Corporation) were included in this single-center, retrospective study. For each eye, TCAABU (estimated from the anterior keratometry values measured with the IOLMaster 700 [Carl Zeiss Meditec AG]) and TCATK (measured using TK IOLMaster 700) were entered into the HOYA Toric Calculator. Patients were operated on based on TCAABU. For each eye, centroid and mean absolute error in predicted residual astigmatism (EPA) were calculated according to TCA used (TCAABU or TCATK). The cylinder power and the axis of the posterior chamber IOL were compared. Results: The mean uncorrected distance visual acuity was 0.07 ± 0.12 logMAR, the mean spherical equivalent was 0.11 ± 0.40 D, and mean residual astigmatism was 0.35 ± 0.36 D. Mean centroid EPA was 0.28 D at 132° with TCAABU and 0.35 D at 148° with TCATK (P(x) <.001; P(y) <.01). Mean absolute EPA was 0.46 ± 0.32 D with TCAABU and 0.50 ± 0.37 D with TCATK (P <.01). In the with-the-rule astigmatism subgroup, a deviation from the target of less than 0.50 D was achieved in 68% of eyes with TCAABU versus 50% of eyes with TCATK. The proposed posterior chamber IOL was different depending on the calculation methods used in 86% of cases. Conclusions: Both calculation methods showed excellent results. However, the predictability error was significantly reduced when TCAABU was used compared to TCATK measured with the IOLMaster 700 in the whole cohort. Finally, TCA was overestimated by TK in the with-the-rule astigmatism subgroup. [J Refract Surg. 2023;39(3):171–179.] [ABSTRACT FROM AUTHOR]

Purpose: Steroid-induced ocular hypertension (OHT) occurs in about a third of cases after dexamethasone implant (DEXi) intravitreal injection (IVI), for which treatment discontinuation may be required. The aim of this study was to assess the benefit of selective laser trabeculoplasty (SLT) in patients who developed transient OHT after DEXi injection to prevent subsequent steroid-induced OHT peaks during reinjections. Methods: A real-life, retrospective, and observational study was conducted to assess the intraocular pressure (IOP) after SLT in steroid responders after DEXi injection (IOP > 21 mmHg). Were analyzed: IOP 1 and 2 months after SLT, maximum IOP (IOPmax) after each new DEXi IVI, and the number of prophylactic hypotensive treatments needed at the time of DEXi reinjections. Results: Thirty-five eyes of 29 patients were included. The mean macular edema follow-up duration was 38.4 ± 28.4 months. SLT was performed after a mean number of 6.3 ± 4.7 DEXi IVIs. After SLT, the IOPmax measured after the first reinjection was lowered by 36.6 ± 14.7% (p < 0.0001). The mean number of hypotensive treatments was 2.1 ± 0.9 before versus 1.5 ± 0.8 after SLT. The post-reinjection lowering in OHT peak was maintained during the subsequent 3 DEXi IVIs: − 29.1 ± 25.5% (p = 0.0009), − 35.8 ± 13.1% (p = 0.0078), and − 45.4 ± 8.6% (p = 0.0312) after the second, third, and fourth DEXi reinjections. SLT allowed continuing injections in 88.6% of patients. Conclusion: The use of 180° SLT in this indication could be an effective therapeutic alternative to control steroid-induced OHT and safely continue DEXi injections. [ABSTRACT FROM AUTHOR]

In recent years, explainable artificial intelligence (XAI) techniques have been developed to improve the explainability, trust and transparency of machine learning models. This work presents a method that explains the outputs of an air-handling unit (AHU) faults classifier using a modified XAI technique, such that non-AI expert end-users who require justification for the diagnosis output can easily understand the reasoning behind the decision. The method operates as follows: First, an XGBoost algorithm is used to detect and classify potential faults in the heating and cooling coil valves, sensors, and the heat recovery of an air-handling unit. Second, an XAI-based SHAP technique is used to provide explanations, with a focus on the end-users, who are HVAC engineers. Then, relevant features are chosen based on user-selected feature sets and features with high attribution scores. Finally, a sliding window system is used to visualize the short history of these relevant features and provide explanations for the diagnosed faults in the observed time period. This study aimed to provide information not only about what occurs at the time of fault appearance, but also about how the fault occurred. Finally, the resulting explanations are evaluated by seven HVAC expert engineers. The proposed approach is validated using real data collected from a shopping mall. [ABSTRACT FROM AUTHOR]

In this paper a control method for a matrix converter (MC) based on the heterodyne concept from the communication field is presented. The method is used to convert the high frequency of a microturbine generator’s (MTG) output voltage to the utility grid’s frequency. In this control method a frequency modulation (FM) of the MC’s switching frequency is achieved using a DQ0 analysis of the converter’s filtered output voltage with the utility grid’s frequency as a reference. After filtration, the MC achieves a conversion to the reference frequency with a minimal total harmonic distortion (THD) of the output voltage while using a low switching frequency. In addition, the proposed method decouples the output frequency, phase angle and voltage amplitude, which allows them to be controlled separately. This significantly simplifies the required control, and enables a robust and low-cost design. The theoretical analysis, simulation and experimental results of the method are reported. [ABSTRACT FROM AUTHOR]

Advanced machine learning techniques have recently demonstrated outstanding performance when applied to power quality disturbance (PQD) classification. Nevertheless, a possible problem is that power experts may find it hard to trust the results of such algorithms, if they do not fully understand the reasons for their outputs. In this light, this article suggests a method that explains the outputs of PQD classifiers, using explainable artificial intelligence (XAI). The method operates as follows: first, various XAI techniques and classifiers are combined and scored based on their explanations during the validation step. Then, the best combination of classifier and XAI technique for each disturbance is used on the testing set, such that the classifier outputs are more transparent. To accomplish these steps, a definition for the correct explanation in PQD is given. Also, to determine the quality of an explanation for a certain output, we propose an evaluation process to measure the explainability score for each XAI technique and classifier. By means of this approach, the PQD classifier outputs are optimized to be both accurate and easy to understand, allowing experts to make informed and trustworthy decisions. [ABSTRACT FROM AUTHOR]

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This paper proposes a power system multimode generator energy loss factor (GELF) based on energy flow method under environmental excitation. This index can evaluate generator damping changes in different oscillation modes in power systems, timely discover the damping deterioration of the generator, and track the source of low‐frequency oscillation. A signal expression method for electrical frequency domain under environmental excitation is derived. This method is combined with dissipated energy flow method to obtain a new type of GELF. In terms of signal processing, dynamic mode decomposition and Morlet wavelet filter extraction system mode components are used to improve computing accuracy. The proposed index enables online calculation with the support of phasor measurement unit and wide area measurement system. Simulation analysis is conducted in a standard 39 node system and wind‐integrated power system. Test results show the effectiveness and generality of the proposed index and method. [ABSTRACT FROM AUTHOR]

Purpose: To assess the impact of intravitreal injections (IVTI) on ocular surface of patients treated with multiple injections. Methods: Prospective, tricentric study conducted in patients treated with unilateral IVTI. An asepsis protocol with povidone‐iodine was used for all patients during IVTI. The primary endpoint was the difference between the pre‐IVTI Ocular Surface Disease Index (OSDI 1) score and that measured on day one (D1) post‐IVTI (OSDI 2). Secondary endpoints were the evaluation of predictive factors for OSDI scores, pain assessment on D1, and the Lacrydiag® analysis of tears from the injected eye versus contralateral eye before IVTI. Results: Two hundred and nineteen patients with a mean age of 75.9 ± 10 years were included. The mean OSDI2‐OSDI1 difference was 19.2 ± 20.6 (p < 0.001). The mean noninvasive tear break‐up time was 6.41 ± 4.59 seconds in the injected eye versus 7.36 ± 4.36 seconds in the contralateral eye (p < 0.001). In the multivariate analysis, the factors significantly associated with the OSDI 2 score were the OSDI 1 score (p < 0.001), the pain score on D1 (p < 0.001) the number of instilled glaucoma eye drop (p = 0.01) and a centre effect (centres 2 and 3 versus centre 1, p < 0.001). Conclusion: Our results confirm the impairment of the ocular surface and quality of life immediately after an IVTI. These results suggest 3 levels of action to improve the immediate tolerance: improving the basal status of the ocular surface, reducing the contact time with povidone‐iodine that might be toxic to the surface, and improving immediate post‐IVTI treatment. [ABSTRACT FROM AUTHOR]

PURPOSE: To assess the impact of the use of artificial tears during the preoperative work-up performed before age-related cataract surgery, when a toric intraocular lens (IOL) was indicated. METHODS: This was a monocentric prospective study assessing 73 eyes of 51 patients, included consecutively after a preoperative work-up performed without artificial tears (no artificial tears group), when a toric IOL was indicated. Each included patient underwent a second series of examinations: biometry using the IOLMaster 700 (Carl Zeiss Meditec AG) and topography using the OPD-Scan II (Nidek), 1 minute after artificial tears instillation (artificial tears group; hyaluronate de sodium 0.15%, threalose 3% [Théalose; Théa]). Changes in anterior corneal astigmatism and subsequent changes in toric IOL calculation were analyzed. The error in predicted residual astigmatism was calculated. RESULTS: Anterior corneal astigmatism and total corneal astigmatism measured with the IOLMaster 700 were significantly modified when artificial tears were instilled before the examinations (1.51 ± 0.57 diopters [D], range: 0.75 to −3.55 vs 1.42 ± 0.63 D, range: 0.42 to 3.35 D; P =.043 and 1.59 ± 0.54 D, range: 0.87 to 3.48 vs 1.51 ± 0.59 D, range: 0.56 to 3.27 D, P =.038, respectively). This modification led to a change in IOL cylinder calculation in 43.8% of cases and to a change in implantation axis greater than 10° in 17.7% of cases. These changes were significantly greater in patients with a breakup time (BUT) less than 5 seconds (57.5% and 27.8%, with P =.009 and.029, respectively). In the subgroup of patients with a BUT of less than 5 seconds, the mean absolute error in predicted astigmatism was significantly lower after artificial tears instillation (0.48 ± 0.50 D, range: 0.00 to 2.79 vs 0.37 ± 0.25 D, range: 0.00 to 1.10 D, P =.048). CONCLUSIONS: Dry eye significantly impacted toric IOL calculations and should be taken into account during the preoperative assessments. Using artificial tears reduced the number of refractive errors. [J Refract Surg. 2021;37(11):759–766.] [ABSTRACT FROM AUTHOR]

In the field of power system dynamics, a main challenge is to properly tune the inverter control parameters, where one important parameter is the inverter's output impedance, physical or virtual. In this work, we provide a proof showing that a minimal output impedance must be used in order to keep the system stable. Although this result is well-known among practicing engineers, our proof reveals a fundamental property which causes instabililty, namely the pole excess of the inverter dynamic model. To prove this claim we model the system as a signal flow diagram, where the output impedances of the inverters are described using static gain feedback. Based on this model, we show that the typical dynamic model of grid supporting inverters has a pole excess larger than 2, which causes instability when high feedback gain is used. This result may be used to design a numerical method for estimating the minimal impedance. The theorem is validated based on an array of photovoltaic plants in the Ramat Negev region, which is part of the Israeli power grid. [ABSTRACT FROM AUTHOR]