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Purpose There are no reported large series of trabeculectomy with mitomycin-C (MMC) in Western patients with primary angle-closure glaucoma (PACG). Our study evaluates long-term tonometric outcomes of trabeculectomy in PACG. Materials and methods This is a retrospective cohort study. The primary outcomes were the Kaplan-Meier success rates on survival analyses using 3 criteria, with or without adjunctive medication: (A) intraocular pressure (IOP) ≤18 mm Hg and IOP reduction of 20%; (B) IOP≤15 mm Hg and IOP reduction 25%; and (C) IOP≤12 mm Hg and IOP reduction 30%. In total, 136 eyes (102 patients) with PACG who underwent trabeculectomy MMC were included. The Cox proportional hazard regression analysis was used to identify risk factors for failure with multivariate analysis (P Results The qualified success rates (±SD) after 1, 3, and 5 years of follow-up for criterion A were 92% (±2.2%), 78% (±3.8%), and 72% (±4.3%); for criterion B, 86% (±3.0%), 65% (±4.4%), and 59% (±4.7%); and for criterion C, 62% (±4.2%), 40% (±4.5%), and 32% (±4.4%). Baseline factors associated with failure were: family history, absence of laser peripheral iridotomy, higher IOP, and presence of a crystalline lens. Conclusions Trabeculectomy with MMC effectively reduces IOP in PACG. Long-term IOP reduction is achieved for target IOP levels in the mid-teens. Presence of a crystalline lens, lack of iridotomy and higher preoperative IOP were associated with higher risks of failure.

Purpose To evaluate the long-term outcomes of second Ahmed glaucoma valve (AGV) implants in eyes with glaucoma. Design Retrospective interventional case series. Methods Patients with sequential second Ahmed valves implanted in the same eye from 1994 to 2016 were included. Success was defined with 3 criteria: (1) intraocular pressure (IOP) ≤ 21 mm Hg and IOP reduction of 20%; (2) IOP ≤ 18 mm Hg and IOP reduction of 25%; and (3) IOP ≤15 mm Hg and IOP reduction of 30%. The primary analysis was the 5-year Kaplan-Meier survival rate for each criterion. Failure was established when the success criterion was not met at 2 consecutive visits at least 3 months after the surgery. Loss of light perception, requirement for additional glaucoma surgery, hypotony maculopathy, and serious complications were also considered failures. Results One hundred ten eyes from 104 patients were included with a mean follow-up of 5.0 years (interquartile range [IQR] 1.6–7.33 years). The median (IQR) age at the second AGV was 68.0 (53.5–77.9) years. The median (IQR) time between surgeries was 2.1 (0.7–4.0) years. The 5-year Kaplan-Meier survival rates were 57%, 51%, and 30% for criteria 1, 2, and 3, respectively. Conclusion A second AGV is effective in reducing IOP in patients who require additional IOP lowering after a first AGV. The success rates are comparable to primary AGV implantation, and to trabeculectomy in eyes with a previously implanted glaucoma drainage device. A second AGV is a viable option in eyes with inadequate IOP levels after a primary AGV.

PURPOSE To compare the assessment of serial visual fields (VFs) based on subjective expert evaluation with the fast and slow VF component rates determined with pointwise exponential regression (PER) and pointwise linear regression (PLR). MATERIALS AND METHODS A total of 5272 VF examinations from 376 eyes diagnosed with open-angle glaucoma were included. Three glaucoma specialists assessed each VF qualitatively to evaluate progression status and the qualitative rate of progression. The rates of VF decay were determined with PER and PLR at each VF location, which were ranked according to the regression coefficient and partitioned into 2 groups (fast and slow). A mean rate for the fast and slow partitions was obtained based on the average of the regression coefficients in each partition. κ-values were used to measure the agreement among the experts and the PER and PLR algorithms. RESULTS The average baseline VF mean deviation for the study sample was -6.6 (±5.9) dB. The agreement of the likelihood of progression among the dichotomized experts' score and PER was moderate (κ=0.41, P

Author(s): Sharifipour, Farideh; Morales, Esteban; Lee, Ji Woong; Giaconi, JoAnn; Afifi, Abdelmonem A; Yu, Fei; Caprioli, Joseph; Nouri-Mahdavi, Kouros | Abstract: PurposeTo test the hypothesis that vertical asymmetry in macular ganglion cell/inner plexiform layer (GCIPL) thickness can improve detection of early glaucoma.MethodsSixty-nine normal eyes and 101 glaucoma eyes had macular imaging with spectral-domain optical coherence tomography (OCT; 200 × 200 cube). The resulting GCIPL thickness matrix was grouped into a 20 × 20 superpixel array and superior superpixels were compared to their inferior counterparts. A global asymmetry index (AI) was defined as the grand mean of the asymmetry ratios. To measure local asymmetry, the corresponding thickness measurements of three rows above and below the horizontal raphe were compared individually and in combinations. Global and local AIs were compared to the best-performing GCIPL thickness parameters with area under the receiver operating curves (AUC) and sensitivity/specificities.ResultsAge or axial length did not influence AIs in normal subjects (P ≥ 0.08). Global and local AIs were significantly higher in the glaucoma group compared to normal eyes. Minimum (AUC = 0.962, 95% confidence interval [CI]: 0.936-0.989) and inferotemporal thickness (AUC = 0.944, 95% CI: 0.910-0.977; P = 0.122) performed best for detection of early glaucoma. The AUC for global AI was 0.851 (95% CI: 0.792-0.909) compared to 0.916 (95% CI: 0.874-0.958) for the best local AI. Combining minimum or inferotemporal GCIPL thickness and the best local AI led to higher partial AUCs (0.088 and 0.085, 90% specificity, P = 0.120 and 0.130, respectively) than GCIPL thickness measures.ConclusionsMacular vertical thickness asymmetry measures did not perform better than sectoral or minimum GCIPL thickness for detection of early glaucoma. Combining local asymmetry parameters with the best sectoral GCIPL thickness measures enhanced this task.

New sources of ancillary services are expected in the power system. For large and conventional generation units the dynamic response is well understood and detailed individual measurement is feasible, which factors in to the straightforward performance requirements applied today. For secure power system operation, a reliable service delivery is required, yet it may not be appropriate to apply conventional performancerequirements to new technologies and methods. The service performance requirements and assessment methods therefore need to be generalized and standardized in order to include future ancillary service sources. This paper develops a modeling method for ancillary services performance requirements, including performance and verification indices. The use of the modeling method and the indices is exemplified in two case studies.

The rising penetration of intermittent energy resources is increasing the need for more diverse electrical energy resources that are able to support ancillary services. Demand side management (DSM) has a significant potential to fulfil this role, but several challenges are still impeding the wide-scale integration of DSM. One of the major challenges is ensuring the performance of the networks that enable communications between control centres and the end DSM resources. This study presents an analysis of all communications networks that typically participate in the activation of DSM, and provides an estimate for the overall latency that these networks incur. The most significant sources of delay from each of the components of the communications network are identified which allows the most critical aspects to be determined. This analysis, therefore, offers a detailed evaluation of the performance of DSM resources in the scope of providing real-time ancillary services. It is shown that, using available communications technologies, DSM can be used to provide primary frequency support services. In some cases, neighbourhood area networks may add significant delay, requiring careful choice of the technologies deployed.

La presente investigación nace como una interrogante ¿cuál es la relación que existe entre el Programa del vaso de Leche y la satisfacción de los beneficiarios? El objetivo general fue determinar la incidencia del Programa alimenticio del vaso de Leche y la satisfacción de los beneficiarios del asentamiento humano “Lomas del Paraíso” del distrito de Villa María del Triunfo, Lima. El universo del estudio es 72 beneficiarios con una muestra de 61 encuestados; el muestreo a utilizar es de tipo probabilístico y el método es oleatorio simple, del cual hemos estudiados a las dos variables. La investigación es de enfoque cuantitativo, descriptiva, correlacional, de diseño no experimenta, de corte transversal, “que recogió la información en un momento específico, al aplicar el instrumento(PROVALECH); Programa vaso de leche a escala de Likert (Nunca, Casi nunca, A veces, Casi siempre, Siempre); el instrumento(SATBENEF); Satisfacción de los beneficiarios a escala de Likert (Nunca, Casi nunca, A veces, Casi siempre, Siempre), que brindaron información acerca de la incidencia que existente entre ” las dos variables y sus respectivas dimensiones.Se utilizó técnicas de correlación de Spearman. Se demostró como conclusión que existe una correlación positiva considerable significativa entre el Programa vaso de leche y la Satisfacción de los beneficiarios del asentamiento humano “Lomas del paraíso” distrito Villa María del Triunfo, Lima. Lima Norte Escuela de Posgrado Administración del Talento Humano

Demand response will become important for the integration of renewable energy sources in the power system. By controlling large pools of small sized consumption units, aggregators of demand response will provide ancillary services to Transmission System Operators and flexibility services to Distribution System Operators and Balance Responsible Parties. Since these services are essential for the secure operation of the grid, the aggregators must be validated. The process applied to traditional ancillary service resources cannot be applied to aggregators since the yare composed by geographically distributed heterogeneous resources. Departing from the current methods employed by Transmission System Operators for validating ancillary service resources, this thesis presents a procedure for validating aggregators. The procedure consists of documentation of the aggregator capabilities and a conceptual framework for aggregator validation testing. The documentation of aggregator capabilities is done through a Functional Reference Architecture for aggregators. The reference architecture identifies the basic functions that an aggregator must posses in order to do a successful service provision. The conceptual validation framework defines the test setup for aggregator validationtests. The validation tests must capture the stochastic nature of the aggregator, therefore the validation procedure makes use of concepts from the field of statistical test design. Benchmark scenarios and service requirements are the inputs to the validationtests. The service requirements are redefined in order to be inclusive of new technologies as ancillary service resources. This is done by redefining services in terms of performance, and removing requirements that assume service provision by large centralized generators. Serviceperformance evaluation and the service verification are the outputs of the validation tests. Also these concepts are redefined to suit the aggregator concept. Through general service models and service performance indices (inspired by the field of Control Performance Assessment), the service provision from aggregators can be evaluated.

This paper presents the failure analysis of a fire water pipe line from a petrochemical industry. Leakages were noticed at the top portion of the pipeline. Severe deep pits were observed at the top inner surface and deposits found at the bottom inner surface of the pipe line. Visual inspection, microscopic examination, chemical and water analyses were employed in the present failure analysis. The analysis results showed that the failure occurred due to the severe oxygen corrosion attack at the top portion of the pipe while the bottom surface of the pipe suffered from under deposit corrosion. The fire water pipe line was made of low carbon steel.

To explore the relationship between the visual field index (VFI) and the visual field mean deviation (MD) in glaucoma patients with moderately advanced perimetric damage and to identify the magnitude of the boundary effect of VFI that occurred when the VFI estimation strategy changed from pattern deviation probability value to total deviation probability value as the MD crossed -20 dB in longitudinal visual field (VF) series.A retrospective cohort study of longitudinal data analysis.The MD and VFI values obtained from VF tests conducted on 148 eyes of 148 glaucoma patients having an MD around -20 dB were studied. A total of 1286 VFs with MD values within the range of -16 dB to -24 dB were included. The eyes were divided into 2 groups, with the first having serial MDs all better than or all worse than -20 dB and the second with serial MDs crossing the -20 dB value. Change in MD (ΔMD) was defined as the absolute difference between the MD values of 2 consecutive VFs. Based on the 2 VFI values of the same VFs, the absolute value of change in VFI (ΔVFI) was calculated.The means (± standard deviation) for the ΔVFI were 4.17% (± 3.3%) in the group of eyes with MDs on either side of -20 dB, and were 15.8% (± 8.4%) in the group with MDs crossing -20 dB (P.0001). For ΔVFI/ΔMD, these values were 6.8%/dB (± 10.5%) when the range of MD falls on either side of -20 dB, and 7.9%/dB (± 6.2%) when the range of MD crosses the -20 dB values (P = .042).The values of the VFI become highly variable in serial VFs of eyes with MDs crossing -20 dB, in comparison to those VFIs associated with MDs on either side of -20 dB. The likelihood for this effect is the change from use of pattern deviation probability value to total deviation probability value in the points included in the calculation of VFI at -20 dB of MD. The development of indices to measure VF rates that are free from this boundary effect in moderately advanced glaucoma is desirable.

Author(s): Rabiolo, Alessandro; Morales, Esteban; Afifi, Abdelmonem A; Yu, Fei; Nouri-Mahdavi, Kouros; Caprioli, Joseph | Abstract: Purpose:To quantify visual field (VF) variability as a function of threshold sensitivity and location, and to compare weighted pointwise linear regression (PLR) with unweighted PLR and pointwise exponential regression (PER) for data fit and prediction ability. Methods:Two datasets were used for this retrospective study. The first was used to characterize and estimate VF variability, and included a total of 4,747 eyes of 3,095 glaucoma patients with six or more VFs and 3 years or more of follow-up. After performing PER for each series, standard deviation of residuals was quantified for each decibel of sensitivity as a measure of variability. A separate dataset was used to test and compare unweighted PLR, weighted PLR, and PER for data fit and prediction, and included 261 eyes of 176 primary open-angle glaucoma patients with 10 or more VFs and 6 years or more of follow-up. Results:The degree of variability changed as a function of threshold sensitivity with a zenith and a nadir at 33 and 11 dB, respectively. Variability decreased with eccentricity and was higher in the central 10° (P l 0.001). Differences among the methods for data fit were negligible. PER was the best model to predict future sensitivity values in the mid term and long term. Conclusions:VF variability increases with the severity of glaucoma damage and decreases with eccentricity. Weighted linear regression neither improves model fit nor prediction. PER exhibited the best prediction ability, which is likely related to the nonlinear nature of long-term glaucomatous perimetric decay. Translational Relevance:This study suggests that taking into account heteroscedasticity has no advantage in VF modeling.

Author(s): Rabiolo, Alessandro; Morales, Esteban; Mohamed, Lilian; Capistrano, Vicente; Kim, Ji Hyun; Afifi, Abdelmonem; Yu, Fei; Coleman, Anne L; Nouri-Mahdavi, Kouros; Caprioli, Joseph | Abstract: Purpose:To compare methods to assess visual field (VF) progression in glaucoma. Methods:4,950 VFs of 253 primary open angle-glaucoma patients were evaluated for progression with the following methods: clinical evaluation, guided progression analysis (GPA), mean deviation (MD), and visual field index (VFI) rates, Advanced Glaucoma Intervention Study (AGIS) and Collaborative Initial Glaucoma Treatment Study (CIGTS) scores, pointwise linear regression (PLR), permutation of PLR (PoPLR), and glaucoma rate index (GRI). A separate simulated series of longitudinal VFs was assessed with all methods except for GPA and clinical evaluation. Results:The average (±SD) age of the patients at baseline was 65.4 (±11.5) years. The average (±SD) follow-up was 11.8 (±4.6) years, and the mean (±SD) number of VFs was 16.8 (±7.0). Proportion of series detected as progressing was 65% for PoPLR, 58% for GRI, 41% for GPA, 40% for PLR, 36% for CIGTS, 35% for clinicians, 31% for MD rate, 29% for AGIS, and 22% for VFI rate. Median times to detection of progression were 7.3 years for PoPLR, 7.5 years for GRI, 11 years for clinicians, 14 years for GPA, 16 years for PLR, 17 years for CIGTS, 19 years for AGIS, and more than 20 years for MD and VFI rates. In simulated VF series, GRI had the highest partial area under the receiver operator characteristic curve (0.040) to distinguish between glaucoma progression and aging/cataract decay, followed by VFI rate (0.028), MD rate (0.024), and PoPLR (0.006). Conclusions:GRI and PoPLR showed the highest proportion of series detected as progressing and shortest times to progression detection. GRI exhibited the best ability to detect progression in the simulated VF series. Translational Relevance:Knowledge of the properties of every method would allow tailoring application in both clinical and research settings.

Glaucoma Macular SD-OCT Outcome Measures: Comparison of Local Structure-Function Relationships and Dynamic Range Arezoo Miraftabi, 1,2 Navid Amini, 1 Esteban Morales, 1 Sharon Henry, 1 Fei Yu, 1,3 Abdolmonem Afifi, 3 Anne L. Coleman, 1 Joseph Caprioli, 1 and Kouros Nouri-Mahdavi 1 Glaucoma Division, Stein Eye Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California, United States 2 Eye Research Center, Rasoul Akram Hospital, Iran University of Medical Sciences, Tehran, Iran Department of Biostatistics, Jonathan and Karin Fielding School of Public Health, University of California, Los Angeles, Los Angeles, California, United States Correspondence: Kouros Nouri- Mahdavi, 100 Stein Plaza, Los An- geles, CA, 90095, USA; nouri-mahdavi@jsei.ucla.edu. Submitted: March 28, 2016 Accepted: July 14, 2016 Citation: Miraftabi A, Amini N, Morales E, et al. Macular SD-OCT outcome measures: comparison of local struc- ture-function relationships and dy- namic range. Invest Ophthalmol Vis Sci. 2016;57:4815–4823. DOI:10.1167/iovs.16-19648 P URPOSE . We tested the hypothesis that the macular ganglion cell layer (GCL) thickness demonstrates a stronger structure-function (SF) relationship and extends the useful range of macular measurements compared with combined macular inner layer or full thickness. M ETHODS . Ninety-eight glaucomatous eyes and eight normal eyes with macular spectral domain optical coherence tomography (SD-OCT) volume scans and 10-2 visual fields were enrolled. Inner plexiform layer (IPL), GCL, macular retinal nerve fiber layer (mRNFL), ganglion cell-inner plexiform layer (GCIPL), ganglion cell complex (GCC), and full thickness (FT) measurements were calculated for 8 3 8 arrays of 38 superpixels. Main outcome measures were local structure- function relationships between macular superpixels and corresponding sensitivities on 10-2 fields after adjusting for ganglion cell displacement, dynamic range of measurements, and the change point (total deviation value where macular parameters reached measurement floor). R ESULTS . Median (interquartile range [IQR]) mean deviation was 7.2 (11.6 to 3.2) dB in glaucoma eyes. Strength of SF relationships was highest for GCIPL, GCL, GCC, and IPL (q ¼ 0.635, 0.627, 0.621, and 0.577, respectively; P 0.046 for comparisons against GCIPL). Highest SF correlations coincided with the peak of GCL thickness, where the dynamic range was widest for FT (81.1 lm), followed by GCC (65.7 lm), GCIPL (54.9 lm), GCL (35.2 lm), mRNFL (27.5 lm), and IPL (20.9 lm). Change points were similar for all macular parameters (7.8 to 8.9 dB). C ONCLUSIONS . GCIPL, GCL, and GCC demonstrated comparable SF relationships while FT, GCC, and GCIPL had the widest dynamic range. Measurement of GCL did not extend the range of useful structural measurements. Measuring GCL does not provide any advantage for detection of progression with current SD-OCT technology. Keywords: macular imaging, SD-OCT, dynamic range, structure-function dentification of glaucoma progression is a pivotal task in day- to-day management of glaucoma, to which various structural and functional measures have been applied. The advent of spectral-domain optical coherence tomography (SD-OCT) has provided the glaucoma research community with a powerful tool for detecting early glaucoma or its progression. Many reports have highlighted the potential role of retinal nerve fiber layer (RNFL), 1,2 although more research is needed to better understand its limitations and the appropriate circumstances for its application. Some recent investigations have demon- strated the utility and added value of macular SD-OCT imaging for detecting glaucoma, but its role remains less well defined with respect to progression. 3–10 Thanks to development of segmentation algorithms applied to SD-OCT imaging, various inner macular parameters are now available to investigators and clinicians. 3,11,12 These include single layer measurements such as ganglion cell (GCL), inner plexiform (IPL), or retinal nerve fiber layer, combination of inner retinal layers such as the ganglion cell-inner plexiform layer (GCIPL) and the ganglion cell complex (GCC), which includes the combined I thickness of the GCIPL and macular RNFL (mRNFL), or the full retinal thickness. The comparative utility of these various thickness parameters for detection of glaucoma progression is unknown. To this aim, the strength of the corresponding structure-function relationships and the comparative dynamic range of these parameters need to be compared. Another issue of interest is the point of change on structure-function plots at which each parameter reaches its measurement floor. We hypothesized that the macular GCL has a stronger correlation with central visual field sensitivities and may extend the range of useful structural measurements compared with other individual or combined inner retinal layers and may be a better outcome measure for detection of glaucoma progression. To this aim, this study was carried out to compare: (1) localized structure-function relationships between GCL and other macular thickness measurements, (2) the dynamic range of macular structural parameters, and (3) the change point for these parameters (i.e., the approximate threshold sensitivity beyond which the structural measures do not provide much additional information). iovs.arvojournals.org j ISSN: 1552-5783 This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

PurposeTo evaluate tonometric outcomes of patients with primary angle closure glaucoma (PACG) who have undergone trabeculectomy with mitomycin C (MMC) with and without concurrent phacoemulsification and to identify risk factors for postoperative failure.Patients and methodsRetrospective cohort study of 44 eyes of 33 phakic patients who underwent trabeculectomy with MMC with or without combined phacoemulsification for PACG. The primary endpoint was qualified tonometric success at 12 months according to predefined criteria. LogMAR visual acuity, number of glaucoma medications, and postoperative complications were also evaluated. Cox proportional hazard regression analysis was performed to identify potential risk factors for trabeculectomy failure.ResultsMean intraocular pressure (IOP) decreased from 21.3±7.9 to 12.2±3.9 mm Hg at 12 months (P1 minute were associated with decreased risk of surgical failure. Concurrent phacoemulsification at the time of trabeculectomy did not alter tonometric success or rate of complications.ConclusionsIn phakic patients with PACG, trabeculectomy with MMC significantly reduces IOP and number of glaucoma medications at 12 months without change in visual acuity. However, success rates are modest when based on more demanding tonometric criteria.

As aggregators become viable sources of ancillary services, they will be required to undergo a validation process similar to the prequalification process of traditional generators. Aggregators are fundamentally different from traditional generators in that they are formed of a large quantity of small heterogeneous resources that are geographically distributed. Therefore, a new test procedure must be designed for the aggregator validation. This work proposes such a procedure and exemplifies is with a study case. The validation of aggregators is essential if aggregators are to be integrated succesfully into the power system.

We characterized humic substances (HS) extracted from a Cu-contaminated soil without compost addition (C) or amended with a wheat straw-based compost (WSC) (H1), co-composted with Fe2O3 (H2), or co-composted with an allophane-rich soil (H3). Extracted HS were characterized under electron microscopy (SEM/TEM), energy-dispersive X-ray (X-EDS), and Fourier transform infrared (FTIR) spectroscopy. In addition, HS extracted from WSC (H4) were characterized at pH 4.0 and 8.0 with descriptive purposes. At pH 4.0, globular structures of H4 were observed, some of them aggregating within a large network. Contrariwise, at pH 8.0, long tubular and disaggregated structures prevailed. TEM microscopy suggests organo-mineral interactions at scales of 1 to 200 nm with iron oxide nanoparticles. HS extracted from soil-compost incubations showed interactions at nanoscale with minerals and crystal compounds into the organic matrix of HS. Bands associated to acidic functional groups of HS may suggest potential sorption interactions with transition metals. We conclude that metal ions and pH have an important role controlling the morphology and configuration of HS from WSC. Characterization of H4 extracted from WSC showed that physicochemical protection of HS could be present in composting systems treated with inorganic materials. Finally, the humified fractions obtained from compost-amended soils may have an important effect on metal-retention, supporting their potential use in metal-contaminated soils.

Author(s): Morales, Esteban; de Leon, John Mark S; Abdollahi, Niloufar; Yu, Fei; Nouri-Mahdavi, Kouros; Caprioli, Joseph | Abstract: PurposeThe study was conducted to evaluate threshold smoothing algorithms to enhance prediction of the rates of visual field (VF) worsening in glaucoma.MethodsWe studied 798 patients with primary open-angle glaucoma and 6 or more years of follow-up who underwent 8 or more VF examinations. Thresholds at each VF location for the first 4 years or first half of the follow-up time (whichever was greater) were smoothed with clusters defined by the nearest neighbor (NN), Garway-Heath, Glaucoma Hemifield Test (GHT), and weighting by the correlation of rates at all other VF locations. Thresholds were regressed with a pointwise exponential regression (PER) model and a pointwise linear regression (PLR) model. Smaller root mean square error (RMSE) values of the differences between the observed and the predicted thresholds at last two follow-ups indicated better model predictions.ResultsThe mean (SD) follow-up times for the smoothing and prediction phase were 5.3 (1.5) and 10.5 (3.9) years. The mean RMSE values for the PER and PLR models were unsmoothed data, 6.09 and 6.55; NN, 3.40 and 3.42; Garway-Heath, 3.47 and 3.48; GHT, 3.57 and 3.74; and correlation of rates, 3.59 and 3.64.ConclusionsSmoothed VF data predicted better than unsmoothed data. Nearest neighbor provided the best predictions; PER also predicted consistently more accurately than PLR. Smoothing algorithms should be used when forecasting VF results with PER or PLR.Translational relevanceThe application of smoothing algorithms on VF data can improve forecasting in VF points to assist in treatment decisions.

Author(s): Caprioli, Joseph; Mohamed, Lilian; Morales, Esteban; Rabiolo, Alessandro; Sears, Nathaniel; Pradtana, Hirunpatravong; Alizadeh, Reza; Yu, Fei; Afifi, Abdelmonem A; Coleman, Anne L; Nouri-Mahdavi, Kouros | Abstract: PurposeTo develop a method to measure the rate of glaucomatous visual field (VF) deterioration and to identify fast progressors.MethodsRetrospective, longitudinal, observational study of 8486 eyes of 4610 glaucomatous patients with ≥6 VFs and ≥3 years of follow-up. A Glaucoma Rate Index (GRI) was calculated. VF locations were partitioned into exponential decay or exponential improvement models. A pointwise rate of change (PRC) was estimated with an exponential fit and expressed as the percent/year change of the age- and location-matched normal perimetric range, presented as a spatially conserved VF map. PRCs were summed and normalized with boundary rates set by simulated decaying and improving VF series on a scale of -100 to +100, respectively.ResultsA total of 89,704 VF examinations with 425,039 test location series was used. Median follow-up and number of VFs/eye were 9.7 years and 9 VFs, respectively. Initial and final mean deviations (±SD) were -4.2 (±5.2) and -5.7 (±6.4) dB. The proportions of test locations designated as decayed, improved, and unchanged were 13%, 4%, and 83%, respectively. Mean PRCs for decay, improvement, and no change were -3.7 (±4.7)%/y, 2.5 (±2.6)%/y, and -0.5 (±2.1)%/y, respectively. The number of eyes with negative and positive GRIs was 5802 (68%) and 2390 eyes (28%), respectively. The proportion of eyes defined as fast progressors was 6.8%.ConclusionsGRI provides a robust measure of glaucomatous VF change, operates without discontinuity over the entire perimetric range, and can be used to identify fast progressors.Translational relevanceThis study describes a novel method that can help the clinician to determine VF progression.

Aggregators are considered to be a key enabling technology for harvesting power system services from distributed energy resources (DER). As a precondition for more widespread use of aggregators in power systems, methods for comparing and validating aggregator designs must be established. This paper proposes a functional reference architecture for aggregators to address this requirement.

Aggregation algorithms that provide services to the grid via demand side management are moving from research ideas to the market. With the diversity of the technology delivering such services, it becomes essential to establish transparent performance standards from a service delivery perspective. This paper formulates performance measures and an index to evaluate in hind sight the quality of service delivery by an aggregator, both with respect to ancillary service and asset management service. The index is based on requirements formulated in service contracts and provides an overall assessment of the quality of service provided by an aggregation control algorithm. By a detailed case study we present and an application of the index, comparing the performance of two different control architectures for demand side management delivering a distribution grid service.

Our aim was to compare fit and predictive performance effectiveness of four pointwise regression models in measuring the visual field (VF) decay rate of progression in patients with open-angle glaucoma. We selected Humphrey VF data of patients with open-angle glaucoma with a minimum follow-up time of 6 years. For each eye (n = 798 from 588 patients), we regressed threshold sensitivity (y) at each VF test location for the entire VF series against follow-up time (x), with four candidate first-order regression models: (1) ordinary least-squares linear regression model (y = β 0 + β 1 x); (2) nondecay exponential regression model (y = β 0 + β 1e x ); (3) decay exponential regression model ( $$ y \,=\, {\text{e}}^{{\beta_{0} + \beta_{1} x}} $$ ); (4) Tobit-censored, maximum-likelihood linear regression model (y* = $$ \beta 0 + \beta 1{\text{x}} + \varepsilon $$ , e ~ N(0, σ2)), where x is follow-up time and y is threshold sensitivity. The average [± standard deviation (SD)] baseline VF mean deviation (MD) was −8.2 (±5.5) dB, the mean follow-up was 8.7 (±1.9) years, and the number of follow-up VFs was 14.7 (±4.4). The decay exponential model was the best-fitting (42.7 % of locations) and best-forecasting (65.5 % of locations) model. The decay exponential model was the best prediction model in all categories of severity. It is not clear that the ordinary least-squares linear regression model is always the favored model for fitting and forecasting VF data in patients with glaucoma. The pointwise decay exponential regression (PER) model was the best-fitting and best-predicting model across a wide range of glaucoma severity and can be readily understood by clinicians.

This paper presents a control scheme based on distributed model predictive control (DMPC) for coordinating flexible distributed energy resources (DER) of heterogeneous type in the Smart Grid with minimum system integration effort. This approach can be used for reducing the peak power exchange between the grid and a cluster of units in the same feeder in price-driven demand response applications. Preliminary simulations prove that the proposed coordination scheme for DMPC succeeds in coordinating flexible DER unit, achieving significant peak shaving when required. The rationale of this approach consists in coordinating independent units equipped with local MPC controller via simple information passing and hiding in the local controllers the units' dynamics.

We tested the hypothesis that the macular ganglion cell layer (GCL) thickness demonstrates a stronger structure-function (SF) relationship and extends the useful range of macular measurements compared with combined macular inner layer or full thickness.Ninety-eight glaucomatous eyes and eight normal eyes with macular spectral domain optical coherence tomography (SD-OCT) volume scans and 10-2 visual fields were enrolled. Inner plexiform layer (IPL), GCL, macular retinal nerve fiber layer (mRNFL), ganglion cell-inner plexiform layer (GCIPL), ganglion cell complex (GCC), and full thickness (FT) measurements were calculated for 8 × 8 arrays of 3° superpixels. Main outcome measures were local structure-function relationships between macular superpixels and corresponding sensitivities on 10-2 fields after adjusting for ganglion cell displacement, dynamic range of measurements, and the change point (total deviation value where macular parameters reached measurement floor).Median (interquartile range [IQR]) mean deviation was -7.2 (-11.6 to -3.2) dB in glaucoma eyes. Strength of SF relationships was highest for GCIPL, GCL, GCC, and IPL (ρ = 0.635, 0.627, 0.621, and 0.577, respectively; P ≤ 0.046 for comparisons against GCIPL). Highest SF correlations coincided with the peak of GCL thickness, where the dynamic range was widest for FT (81.1 μm), followed by GCC (65.7 μm), GCIPL (54.9 μm), GCL (35.2 μm), mRNFL (27.5 μm), and IPL (20.9 μm). Change points were similar for all macular parameters (-7.8 to -8.9 dB).GCIPL, GCL, and GCC demonstrated comparable SF relationships while FT, GCC, and GCIPL had the widest dynamic range. Measurement of GCL did not extend the range of useful structural measurements. Measuring GCL does not provide any advantage for detection of progression with current SD-OCT technology.

Economic Model Predictive Control (MPC) is very well suited for controlling smart energy systems since electricity price and demand forecasts are easily integrated in the controller. Electric vehicles (EVs) are expected to play a large role in the future Smart Grid. They are expected to provide grid services, both for peak reduction and for ancillary services, by absorbing short term variations in the electricity production. In this paper the Economic MPC minimizes the cost of electricity consumption for a single EV. Simulations show savings of 50–60% of the electricity costs compared to uncontrolled charging from load shifting based on driving pattern predictions. The future energy system in Denmark will most likely be based on renewable energy sources e.g. wind and solar power. These green energy sources introduce stochastic fluctuations in the electricity production. Therefore, energy should be consumed as soon as it is produced to avoid the need for energy storage as this is expensive, limited and introduces efficiency losses. The Economic MPC for EVs described in this paper may contribute to facilitating transition to a fossil free energy system.

Número de publicación: 2 283 191 Número de solicitud: 200502143, Biomasa de pulpa de oliva con alto contenido en antioxidantes fenólicos, procedimiento de obtención, formulaciones y usos de las mismas. La presente invención proporciona una biomasa de pulpa de oliva con alto contenido en antioxidantes fenólicos tales como tirosol, ácido p-hidroxibenzoico, ácido p-hidroxifenilacético, ácido p-hidroxifenilpropiónico, ácido vaníllico, hidroxitirosol, ácido protocatéquico, 3,4-dihidroxifenilglicol, ácido beta-fenil-láctico, ácido p-hidroxicinámico, ácido cis-cafeico o ácido trans-cafeico, en unas concentraciones determinadas. Dicha biomasa se obtiene mediante un procedimiento que comprende añadir una mezcla de vitamina E y ascorbil palmitato a la pasta de olivas trituradas previamente a su centrifugación para separar el aceite de la biomasa. Asimismo, la invención proporciona también formulaciones que comprenden dicha biomasa y el uso de las mismas en aplicaciones farmacéuticas, alimentarias o cosméticas., Universidad de Granada

PURPOSE We investigated the longitudinal relationships between the changes in neuroretinal rim area (RA) and the slow (SC) and fast (FC) components of visual field (VF) decay at various stages of glaucoma. METHODS We divided 465 eyes of 338 patients into glaucoma suspect, and preperimetric, early, and moderate/advanced glaucoma. All patients had a minimum of 3 confocal scanning laser ophthalmoscopic examinations and 4 VF tests with follow-up of 4 or more years. A pointwise exponential regression was used to perform trend analyses on thresholds at each VF test location, which was partitioned into SC and FC. A mixed effects linear model was used to explore the associations of RA change with mean deviation (MD), visual field index (VFI), SC, and FC. RESULTS Decreased RA was associated with lower mean threshold sensitivities of FC regardless of baseline severity of glaucoma (P ≤ 0.03). The mean threshold sensitivities in SC were not correlated with RA change at any stage. Decreased RA was correlated with worse MD in preperimetric, early, and moderate/advanced glaucoma (P < 0.05). Decreased RA was correlated with worse VFI in preperimetric and early glaucoma only (P ≤ 0.04). CONCLUSIONS A decrease in rim area was significantly correlated with the fast VF component regardless of the baseline severity of glaucoma. Mean deviation and VFI correlated with change of rim area only in certain stages of glaucoma. The identification of the fast component seems a more robust and useful measure of glaucomatous change than MD or VFI.

Importance A visual field parameter that is resistant to cataract formation and extraction would help monitor glaucomatous visual field progression in patients with coexisting glaucoma and cataract. Objective To evaluate the effect of cataract surgery on the slow and fast components of visual field decay in a group of patients with glaucoma. Design, Setting, and Participants Retrospective, interventional, longitudinal study. Eighty-five eyes of 68 patients with open-angle glaucoma who had cataract extraction were included. All patients had 5 or more reliable visual field measurements before and after surgery. Interventions A pointwise exponential regression was used to perform trend analysis on thresholds at visual field test locations before and after cataract surgery. The test locations were ranked according to the decay rate and were partitioned into slow and fast groups. Main Outcomes and Measures The slow and fast visual field rate components were measured before and after cataract surgery and were compared. Linear regressions of the mean deviation and the visual field parameter were performed against time and were compared before and after surgery. Results The mean (SD) mean deviation was −5.5 (5.1) dB before cataract surgery and −5.0 (4.9) dB after cataract surgery ( P = .002). The mean (SD) Visual Field Index was 86.4% (13.5%) before cataract surgery and 86.6% (13.3%) after cataract surgery ( P = .30). The mean (SD) slow component rate decreased from 0.48% (0.73%) per year before surgery to 0.26% (0.42%) per year after surgery ( P = .04). No statistically significant difference was identified in the fast component mean (SD) rate per year before surgery (3.37% [4.05%]) vs per year after surgery (3.46% [3.56%]) ( P = .29). Conclusions and Relevance Cataract progression seems to be the main determinant for the slow visual field rate component and does not change the fast visual field rate component. We conclude that the method used can help reduce the confounding effects of cataract progression and cataract extraction on measured perimetric progression in glaucoma.

PURPOSE To investigate baseline prognostic factors predicting rapid deterioration of the visual field in primary open-angle glaucoma patients. METHODS Seven hundred sixty-seven eyes of 566 glaucoma patients from the Advanced Glaucoma Intervention Study (AGIS) and the clinical database from Jules Stein Eye Institute's Glaucoma Division were included. The rates of decay at each visual field test location were calculated with pointwise exponential regression analysis (PER), and the rates were separated into faster and slower components for each series. Subjects with a faster component decay rate (≥ 36%/y) were defined as rapid progressors. Sex, race, age, visual acuity, intraocular pressure, mean deviation (MD), number of medications, use of diabetic or hypertension medications, and vertical cup-to-disc ratio at baseline were entered in a multivariable prognostic logistic regression model. RESULTS The average (± SD) MD was -8.02 (± 6.13), and the average age was 68.64 (± 11.71) years for the study group. Two hundred twenty-two eyes (28.9%) were identified as rapid progressors. The following baseline factors were predictors of faster deterioration: worse MD (P < 0.001, odds ratio [OR]: 1.11; 95% confidence interval [CI]: 1.07-1.15), larger vertical cup-to-disc ratio (P = 0.001, OR: 1.23; 95% CI: 1.09-1.39), and older age (P = 0.02, OR: 1.24; 95% CI: 1.04-1.48). After excluding the variables related to glaucoma severity at baseline (baseline MD and baseline vertical cup-to-disc ratio), the likelihood of being a rapid progressor was 54% greater in African Americans than in Caucasians (P = 0.03, OR: 1.55; 95% CI: 1.06-2.27). CONCLUSIONS Patients with more severe glaucomatous damage, as measured by both visual field or optic disc cupping and older age, are at highest risk for rapid worsening of the disease, as are African Americans compared to Caucasians. More aggressive treatment of such patients should be considered to prevent visual disability.

PurposeTo examine the prevalence of visual field deterioration in contralateral eyes of patients with worsening open-angle glaucoma and to evaluate the spatial concordance of visual field deterioration between both eyes.MethodsOne hundred sixteen open-angle glaucoma patients who underwent 8 or more visual field examinations over ≥ 6 years of follow-up were included. The rates of the fast and slow components of visual field decay for each of 52 visual field test locations were calculated with point-wise exponential regression analysis. The spatial concordance of visual field deterioration in contralateral eyes was evaluated with a concordance ratio (calculated as the number of overlapping locations divided by the total number of deteriorating locations) and by comparing the rate of decay in corresponding modified glaucoma hemifield test clusters.ResultsThe average visual field mean deviation (± standard deviation [SD]) was -8.5 (± 6.4) dB and the mean (± SD) follow-up time was 9.0 (± 1.6) years. Sixty-three patients had mild damage, 23 had moderate damage, and 30 had severe damage. The mean concordance ratio (± SD) was 0.46 (± 0.32) for the mild group, 0.33 (± 0.27) for the moderate group, and 0.35 (± 0.21) for the severe group. Thirty-one patients (27%) had deterioration in concordant locations (p < 0.05). Visual field deterioration was greater in the superior hemifield than the inferior hemifield (p < 0.05) when evaluated with both the concordance ratio and modified glaucoma hemifield test cluster analysis methods.ConclusionsThere is only fair spatial concordance with regard to visual field deterioration between the both eyes of an individual. We conclude that testing algorithms taking advantage of inter-eye spatial concordance would not be particularly advantageous in the early detection of glaucomatous deterioration.