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1.
Heliyon ; 10(2): e24760, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38304849

RESUMEN

In this work, a two-level control system is used to minimize the total active power losses of an active distribution system connected to the external grid and composed of a wind turbine, two photovoltaic power sources, and two batteries. At the first control level, a model-based predictive control (MPC) is run, using non-homogeneous Markov reward models for wind power prediction and homogeneous Markov reward models for photovoltaic power. At the second level, an algorithm is run for optimal management of voltage control assets, such as voltage regulating transformers, to minimize losses. Different scenarios have been considered, highlighting the advantages of using an MPC framework. This results in an optimization process that can be influenced by different time horizons depending on whether or not the MPC is applied. The predictions allow considering a long-horizon stepwise optimization process that leads to an increasing number of variables along with the decrease of total active power losses. When the MPC is not applied, a short-horizon analysis is performed with a decrease in both the number of variables and the quality of the results. Different cases are considered in which the nominal power of a photovoltaic unit and the battery capacity are modified.

2.
Retina ; 43(12): 2118-2122, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37983379

RESUMEN

PURPOSE: To describe and evaluate the effectiveness of stripping the posterior hyaloid as vitreomacular traction treatment. METHODS: This prospective, consecutive, interventional study examined 10 eyes of 10 patients who underwent vitrectomy for vitreomacular traction. RESULTS: The best-corrected visual acuity improved from 20/63 (0.5 ± 0.18 logMAR) preoperatively to 20/36 (0.25 ± 0.15 logMAR) 3 months after the surgeries. Optical coherence tomography analysis showed a reduction of the mean foveal thickness from 462 ± 82 µ to 372 ± 28 µ at 3-month follow-up in all the eyes. No postoperative complications were reported. CONCLUSION: Stripping of the posterior hyaloid for the treatment of vitreomacular traction could improve the symptoms and visual acuity of patients, alleviating the traction on the macula and avoiding secondary retinal damage as macular hole formation.


Asunto(s)
Enfermedades de la Retina , Perforaciones de la Retina , Humanos , Tracción/efectos adversos , Estudios Prospectivos , Retina , Enfermedades de la Retina/diagnóstico , Trastornos de la Visión/cirugía , Perforaciones de la Retina/diagnóstico , Perforaciones de la Retina/cirugía , Perforaciones de la Retina/complicaciones , Vitrectomía/métodos , Tomografía de Coherencia Óptica , Estudios Retrospectivos
3.
Ophthalmologica ; 246(1): 58-67, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36843038

RESUMEN

INTRODUCTION: The aim of this study was to explore the early efficacy and safety of treatment with intravitreal injections (IVIs) of brolucizumab in patients presenting with neovascular age-related macular degeneration (nAMD) in a real-world setting. METHODS: This retrospective study included 194 eyes of 180 patients with nAMD treated with standard 6-mg IVIs of brolucizumab in our clinic between March 11, 2021, and June 15, 2022. Both treatment-naive (33 eyes) and switch therapy patients (161 eyes) were included in the study. Best corrected visual acuity (BCVA), central subfield thickness (CST), retinal fluid distribution (classified as intraretinal, subretinal, under the pigmented epithelium), treatment intervals, and adverse event rates were collected for analysis. RESULTS: Average follow-up time was 37.2 ± 16.6 weeks. Mean baseline BCVAs were 38.1 ± 4.5 and 41.9 ± 6.7 letters in the treatment-naive and switch therapy groups, with a final gain of 16.0 ± 4.9 (p < 0.0001) and 10.7 ± 5.9 (p < 0.0001) letters in the two groups, respectively. Throughout the study period, CST significantly decreased in both treatment naïve (from 352.0 ± 129.4 to 284.2 ± 93.8 µm; p = 0.0015) and switch therapy (from 369.9 ± 140.5 to 307.4 ± 123.5 µm; p < 0.0001). Significant fluid control rates were achieved at the end of the study period (45% and 27% eyes were completely free of fluid in naïve and switch groups, respectively). Five eyes (2.6%) developed adverse events with different grades of intraocular inflammation and visual outcomes. CONCLUSION: Brolucizumab IVI showed very good anatomical and functional outcomes in both naive and switch patients in this real-world experience. Nevertheless, even showing a favorable risk/benefit profile, clinicians and patients should be aware of the possibility of a small rate of severe complications.


Asunto(s)
Inhibidores de la Angiogénesis , Degeneración Macular Húmeda , Humanos , Estudios Retrospectivos , Factor A de Crecimiento Endotelial Vascular , Receptores de Factores de Crecimiento Endotelial Vascular/uso terapéutico , Agudeza Visual , Degeneración Macular Húmeda/diagnóstico , Degeneración Macular Húmeda/tratamiento farmacológico , Inyecciones Intravítreas , Proteínas Recombinantes de Fusión/uso terapéutico , Tomografía de Coherencia Óptica
4.
Retina ; 43(11): 2034-2036, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34731095

RESUMEN

PURPOSE: To describe and evaluate the effectiveness of the modified Carlevale intraocular lens (IOL) fixation technique, using two vitrectomy ports as lens plug fixation sites. MATERIALS AND METHODS: This prospective, consecutive, interventional study examined 60 eyes in 60 patients, who underwent 25- or 23-gauge vitrectomy for an IOL subluxation/luxation, lens dislocation, or aphakia, with Carlevale IOL implantation. RESULTS: Postoperatively, transient ocular hypotension was observed in four eyes. The mean refractive prediction error was -0.27 ± 0.78 diopters. No postoperative complications, such as retinal detachment, endophthalmitis, or IOL dislocation, were observed in the 4-month follow-up. CONCLUSION: This new technique may be simple, fast, and effective because of fewer scleral wounds and fewer postoperative complications.


Asunto(s)
Subluxación del Cristalino , Lentes Intraoculares , Humanos , Implantación de Lentes Intraoculares/métodos , Vitrectomía/métodos , Estudios Prospectivos , Esclerótica/cirugía , Agudeza Visual , Subluxación del Cristalino/cirugía , Complicaciones Posoperatorias/cirugía , Estudios Retrospectivos , Técnicas de Sutura
5.
J Appl Stat ; 49(15): 3908-3927, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36324481

RESUMEN

In this study, we consider different poverty indexes in a dynamic framework where individuals change their rate of income randomly in time. The primary objective of this paper is to assess the accuracy of the approximation of the indexes that can be obtained by applying the strong law of large numbers to an economic system composed of an infinite number of agents. The main result is a multivariate central limit theorem for dynamic poverty measures, which is obtained applying the theory of U-statistics. We also show how to get the confidence sets for the considered dynamic indexes, which show the appropriateness of the model. An application to the Italian income data from 1998 to 2012 confirms the effectiveness of the considered approach and the possibility to determine the evolution of poverty and inequality in real economies.

6.
Am J Ophthalmol ; 240: 30-36, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35227693

RESUMEN

PURPOSE: To report the 1-year results of human amniotic membrane patch implantation for optic disc pit maculopathy. DESIGN: A prospective, consecutive, interventional study. METHODS: Eleven eyes of 11 patients affected by optic disc pit maculopathy associated with subretinal/intraretinal fluid were included in this single-institution study. A 25-gauge pars plana vitrectomy was performed in all cases, with an implant of a human amniotic membrane patch into the optic disc pit and air was injected as endotamponade. The primary study outcome was the subretinal and intraretinal fluid reabsorption. Secondary outcomes were visual acuity improvement and postoperative complications. RESULTS: Mean central retinal thickness gradually diminished from 512 ± 137 µm to 243 ± 19 µm, at the 12-month follow-up. The mean visual acuity improved from 20/80 at baseline to 20/32 at the 12-month follow-up. Complete fluid resorption occurred in 9 of 11 (81.8%) eyes and there was partial resorption in 2 eyes (18%). No subretinal fluid recurrence was observed during the 12-month follow-up. No intraoperative or postoperative complications were reported during the follow-ups. The amniotic membrane patch remained detectable inside the pit for the entire follow-up time. CONCLUSION: An amniotic membrane plug may be effective for improving optic disc pit maculopathy. All cases had an anatomical improvement and encouraging visual acuity recovery.


Asunto(s)
Anomalías del Ojo , Degeneración Macular , Disco Óptico , Enfermedades de la Retina , Amnios , Anomalías del Ojo/complicaciones , Anomalías del Ojo/diagnóstico , Anomalías del Ojo/cirugía , Estudios de Seguimiento , Humanos , Degeneración Macular/complicaciones , Complicaciones Posoperatorias/cirugía , Estudios Prospectivos , Enfermedades de la Retina/complicaciones , Estudios Retrospectivos , Tomografía de Coherencia Óptica/métodos , Vitrectomía/métodos
7.
Neuromuscul Disord ; 30(2): 144-150, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32005494

RESUMEN

The purpose of the study is to evaluate retinal involvement in a cohort of patients affected by Myotonic Dystrophy type 1 (DM1). Both eyes of 30 patients and one eye of a 31st patient with genetically proven diagnosis of DM1 and both eyes of 20 healthy age- and gender-matched subjects were enrolled. All patients underwent complete ophthalmologic examination including best-corrected visual acuity, intraocular pressure measurement, fundoscopy, fundus autofluorescence, infrared imaging and spectral-domain optical coherence tomography with central macular thickness measurement. DM1 patients showed statistically significant higher central macular thickness values than controls. In the DM1 group, butterfly (14.8%) and reticular (13.1%) pigment abnormalities were found with corresponding drusenoid deposit and focal disruption of photoreceptor and retinal pigment epithelium layers. Compared with the controls, DM1 group had higher prevalence of epiretinal membrane. In the DM1 group, the prevalence of epiretinal membrane and retinal pigment epithelium alterations were directly correlated with age, whereas no correlation was found with disease duration, CTG expansion and MIRS score. In conclusion, in addition to the typical retinal pigment epithelium changes, DM1 is also associated with abnormalities of the vitreoretinal interface, particularly epiretinal membrane, resulting in central macular thickness increase. Both inner and outer retinal alterations were associated with increasing age, suggesting that DM1 may cause a premature aging of the retina.


Asunto(s)
Membrana Epirretinal/patología , Mácula Lútea/patología , Distrofia Miotónica/patología , Epitelio Pigmentado de la Retina/patología , Desprendimiento del Vítreo/patología , Adulto , Factores de Edad , Anciano , Envejecimiento Prematuro/patología , Membrana Epirretinal/diagnóstico por imagen , Membrana Epirretinal/etiología , Femenino , Estudios de Seguimiento , Humanos , Mácula Lútea/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Distrofia Miotónica/complicaciones , Distrofia Miotónica/diagnóstico por imagen , Epitelio Pigmentado de la Retina/diagnóstico por imagen , Índice de Severidad de la Enfermedad , Tomografía de Coherencia Óptica , Desprendimiento del Vítreo/diagnóstico por imagen , Desprendimiento del Vítreo/etiología , Adulto Joven
8.
Eur J Pharm Sci ; 34(2-3): 118-28, 2008 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-18420389

RESUMEN

Minocycline is a widely used antibacterial agent. Moreover, it is also demonstrated to be effective in several neurodegenerative disorders, due to its antioxidant and anti-inflammatory activities. However, the last activity is only apparent at very high doses. In fact, minocycline poorly crosses the blood-brain barrier (BBB) due to its low lipophilicity and half-life. The present work details the physicochemical characterization of a series of alkanoyl-10-O-minocycline derivatives (2-6), which are able to produce self-assembled aggregates in aqueous solution. The n-octanol/aqueous phase lipophilicity of minocycline and its derivatives were assessed by theoretical calculation, by shake-flask method, and by reversed-phase HPLC. Moreover, we determined their affinity for membrane phospholipids measuring their HPLC retention on phospholipid-based stationary phases, the so-called "Immobilized Artificial Membranes" (IAMs). Our results indicate high lipophilicity values for the minocycline derivatives (compounds 2-6); these values and the corresponding phospholipid affinities increase with the length of the hydrocarbon moiety substituent. Furthermore, the ability of the investigated alkanoyl-10-O-minocycline derivatives to self-assemble could allow a direct administration by oral and intraperitoneal routes as supramolecular systems. The advantages are an enhancement of drug solubilization, a sustained release, and the consequent less frequent drug administration. Moreover, we can hypothesize the potential solubilization in the micellar core of other poorly water soluble drugs which could improve the therapeutic effects of the pharmaceutical formulation in a combined therapy. Given the high lipophilicity of the title derivatives, they can be supposed to offer higher half-life and a better BBB penetration than minocycline. Since the new derivatives retain the structural features related to the antioxidant and anti-inflammatory effects of minocycline, they can be regarded not only as long-acting antimicrobial agents but also as candidate drugs for a targeted treatment of mental illness.


Asunto(s)
Alcanos/síntesis química , Minociclina/síntesis química , Enfermedades Neurodegenerativas/tratamiento farmacológico , Alquilación , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Indicadores y Reactivos , Micelas , Pruebas de Sensibilidad Microbiana , Minociclina/uso terapéutico , Espectrofotometría Ultravioleta
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