First record of partial albinism in the critically endangered Angelshark (Squatina squatina) (Linnaeus, 1758).

We report the first case of partial albinism in the Critically Endangered angelshark, Squatina squatina. The encounter with this specimen took place while SCUBA diving on the beach of Tufia, located on the east coast of the island of Gran Canaria on 2 April 2021. This is also the first confirmed finding of an albino elasmobranch specimen in the Canary Island archipelago.

Preliminary assessment of the impact of Covid-19 Pandemic in the small-scale and recreational fisheries of the Canary Islands.

Covid-19 pandemic has affected worldwide in many different ways. Fisheries around the world are not an exception due to the long-term isolation and the non-activities period suffered. To do an evaluation of its impact on the fishing sectors in the Canary Islands, 87 online and phone questionnaires were carried out between July and September 2020, conducting the interviews to artisanal fishermen, fishmongers, recreational charter boats fishermen and tackle shops along the archipelago. Both, the artisanal and recreational fishing sectors have been affected by this pandemic, but in an unequal manner. The drop of the demand of fresh fishing products in the islands markets due to the closure of hotels, restaurants and other services, and the highly significant decreasing in the number of tourists, provoked an estimated income loss for the artisanal fishermen about the 40% on average, but the majority of vessels continued their activities during the pandemic, with very limited effects on direct employment. However, the fishmonger's activity apparently was not affected and increased their monthly income in relation to the previous year. Likewise, the infeasibility of fishing charter companies due to the great reduction in the number of tourists contrasted with the significant increase in the number of recreational fishing licenses immediately after the confinement ended. Even though that fishing tackle shops increased sales by over 60% in relation to the similar period of the year before, only 4.4% of these shops declared not to have had economic losses.

Historical photographs of captures of recreational fishers indicate overexploitation of nearshore resources at an oceanic island.

In this study, we used a historical collection of photographs taken by recreational fishers from 1940 to 2014, at the island of Gran Canaria, to show both a significant decrease in the mean total length of Epinephelus marginatus and a concurrent change in the composition of captures. Before 1980, the mean total length of fish caught and photographed was c. 100 cm, while after 2009 this was typically < 40 cm. Before 1980, the predominant captured species was E. marginatus (an apex predator), but currently the majority of catches are of omnivorous species, in particular the parrotfish, Sparisoma cretense and seabreams Diplodus spp. Overall, integration of these results indicates a qualitative and quantitative variation in captures of recreational fishers, probably as a sign of change in ecological balances and the overfished status of many target species.

Temporal and spatial predictions of effect of alternative fishing policies for the Gran Canaria marine ecosystem.

In this paper we consider what may happen to the marine ecosystem of Gran Canaria Island within the 2030 horizon, if fishing strategies different from those currently in place were implemented and we evaluate the effect of, for example, reduction of recreational-artisanal fishing, limitation of catches (e.g. total allowable catches, TAC), or spatial distribution of fishing sectors. From all scenarios tested, only those that significantly reduce the high effort of the recreational fishing would allow the recovery of the most exploited stocks in the marine ecosystem in the short and medium-term. Moreover, the best management strategy, in contribution to abundance, was obtained with a scenario that has a spatial partition of exploitation rights between artisanal and recreational fishermen and includes no-fishing zones (NTZ). This work is a first attempt to use spatial and temporal models to assess the effectiveness of alternative fishery policies in the Canary Islands.

Low Prevalence of Biopsy-Proven Eosinophilic Esophagitis in Patients with Esophageal Food Impaction in Mexican Population.

BACKGROUND: Eosinophilic esophagitis (EoE) is the most common cause of dysphagia and esophageal food impaction (EFI) in the USA, Western Europe, and Australia. In Mexico, the uncomplicated form of this disease is infrequent, and prevalence in patients with EFI is unknown. AIMS: To determine the prevalence and causes of EFI, endoscopic and therapeutic aspects, and establish the prevalence of biopsy-proven EoE in patients with EFI. METHODS: Diagnostic upper gastrointestinal endoscopy reports from January 2011 to December 2016 were retrospectively reviewed. Patients with therapeutic procedures, gastrointestinal hemorrhage, or non-food foreign body impaction were excluded. The number of patients with EFI was determined. Additionally, patients with esophageal biopsy were retained for EoE prevalence calculation. The diagnosis of EoE was defined with the presence of eosinophil infiltration count ≥ 15/high-power field with or without typical endoscopic abnormalities. RESULTS: A total of 4700 reports of the same number of patients were selected; 2209 were males (47%) with a mean age of 57.6 ± 12.3 years (range 14-93). We identified 36 patients with EFI (0.76, 95% CI 0.51-1.01), 16 males (44.4%) with a mean age of 54.9 ± 19.7 (range 22-92). Esophageal biopsies were obtained in 17/36 (47.2%) cases. The diagnosis of EoE was confirmed in 2 patients (11.7%). Peptic stenosis was the most frequent cause of EFI. CONCLUSIONS: EoE is an infrequent cause of EFI in the Mexican population (11.7%). EoE had the lowest prevalence compared to that reported in Caucasian populations. The prevalence of EFI was also low.

Visual Discrimination Increase by Yellow Filters in Retinitis Pigmentosa.

PURPOSE: The objective of this study was to evaluate, by halometry and under low illumination conditions, the effects of short-wavelength light absorbance filters on visual discrimination capacity in retinitis pigmentosa patients. METHODS: This was an observational, prospective, analytic, and transversal study on 109 eyes of 57 retinitis pigmentosa patients with visual acuity better than 1.25 logMAR. Visual disturbance index (VDI) was determined using the software Halo 1.0, with and without the interposition of filters which absorb (totally or partially) short-wavelength light between 380 and 500 nm. RESULTS: A statistically significant reduction in the VDI values determined using filters which absorb short-wavelength light was observed (p < 0.0001). The established VDIs in patients with VA logMAR <0.4 were 0.30 ± 0.05 (95% CI, 0.26-0.36) for the lens alone, 0.20 ± 0.04 (95% CI, 0.16-0.24) with the filter that completely absorbs wavelengths shorter than 450 nm, and 0.24 ± 0.04 (95% CI, 0.20-0.28) with the filter that partially absorbs wavelengths shorter than 450 nm, which implies a 20 to 33% visual discrimination capacity increase. In addition, a decrease of VDI in at least one eye was observed in more than 90% of patients when using a filter. CONCLUSIONS: Short-wavelength light absorbance filters increase visual discrimination capacity under low illumination conditions in retinitis pigmentosa patients. Use of such filters constitutes a suitable method to improve visual quality related to intraocular light visual disturbances under low illumination conditions in this group of patients.

Prevalence of refractive errors in children in Equatorial Guinea.

PURPOSE: The aim of this work is to evaluate the epidemiological aspects of the refractive errors in school-aged children in Malabo (Island of Bioko), Equatorial Guinea (western-central Africa). METHODS: A total of 425 schoolchildren (209 male subjects and 216 female subjects, aged between 6 and 16 years) were examined to evaluate their refraction errors in Malabo, Equatorial Guinea (western-central Africa). The examination included autorefraction with cycloplegia, measurement of visual acuity (VA) for far vision, and the curvature radii of the main meridians of the anterior surface of the cornea. RESULTS: A low prevalence of myopia was found (≤-0.50 diopters [D] spherical equivalent), with unilateral and bilateral myopia being 10.4 and 5.2%, respectively. The prevalence of unilateral and bilateral hypermetropia (≥2.0 D spherical equivalent) was 3.1 and 1.6%, respectively. Astigmatism (≤-0.75 D) was found in unilateral form in 32.5% of these children, whereas bilateral astigmatism was found in 11.8%. After excluding children having any ocular pathology, the low prevalence of high refractive errors signified good VA in these children. Significant differences were found in the distribution of the refractive errors by age and type of schooling (public or private) but not by sex. In general, the radii of the anterior of the cornea did not vary significantly with age. CONCLUSIONS: The mean refractive errors found were low and therefore VA was high in these children. There was a low prevalence of myopia, with significantly higher values in those who attended private schools (educationally and socioeconomically more demanding). Astigmatism was the most frequent refractive error.

A visual test based on a freeware software for quantifying and displaying night-vision disturbances: study in subjects after alcohol consumption.

BACKGROUND: In this work, we propose the Halo test, a simple visual test based on a freeware software for quantifying and displaying night-vision disturbances perceived by subjects under different experimental conditions, more precisely studying the influence of the alcohol consumption on visual function. METHODS: In the Halo test, viewed on a monitor, the subject's task consists of detecting luminous peripheral stimuli around a central high-luminance stimulus over a dark background. The test, performed by subjects before and after consuming alcoholic drinks, which deteriorate visual performance, evaluates the influence that alcohol consumption exerts on the visual-discrimination capacity under low illumination conditions. Measurements were made monocularly and binocularly. Pupil size was also measured in both conditions (pre/post). Additionally, we used a double-pass device to measure objectively the optical-quality of the eye and corroborate the results from the Halo test. RESULTS: We found a significant deterioration of the discrimination capacity after alcohol consumption, indicating that the higher the breath-alcohol content, the greater the deterioration of the visual-discrimination capacity. After alcohol intake, the graphical results showed a greater area of undetected peripheral stimuli around the central high-luminance stimulus. An enlargement of the pupil was also observed and the optical quality of the eye was deteriorated after alcohol consumption. CONCLUSIONS: A greater influence of halos and other night-vision disturbances were reported with the Halo test after alcohol consumption. The Halo freeware software constitutes a positive contribution for evaluating nighttime visual performance in clinical applications, such as reported here, but also in patients after refractive surgery (where halos are present) or for monitoring (time course) some ocular pathologies under pharmacological treatment.

Life History Parameters and Fishing Aspects of the Alien Nimble Spray Crab Percnon gibbesi in a Native Area of the Central-East Atlantic.

Percnon gibbesi is a native crab species characteristic of intertidal and subtidal zones of the Atlantic coast of the European Macaronesian archipelagos (Azores, Madeira, and Canary Islands), and probably also in the neighbouring rocky coasts of northwest Africa. P. gibbesi is considered an invasive alien species in almost all of the Mediterranean, with expanding populations from Spain to Turkey, including Libya; However, its biology and ecology are highly unknown, despite all its range of distribution. In the intertidal zones of Gran Canaria Island, this crab, in the intertidal zones of Gran Canaria Island, shows a carapace length range between 4.1 and 22.7 mm (4.1-22.7 in males and 5.7-22.3 in females), where females showed higher weights and lengths than males on average; However, males predominated in all samples, with a sex ratio of 1:0.57. The L∞ for this crab was estimated to be 27 ± 3 mm (23 ± 4 mm for females and 25 ± 4 mm for males). The growth coefficient (K) was 0.24 year-1, the total mortality (Z) was Z = 1.71 year-1, and the natural mortality (M) was 0.47 year-1. Although females grow faster than males, males are more abundant in the larger length classes. Although the presence of ovigerous females indicated that reproduction takes place twice a year, from March to April and from August to September, the number of cohorts detected by the modal progression analysis showed that reproduction takes place all year.

Aggregative Behaviour of Spiny Butterfly Rays (Gymnura altavela, Linnaeus, 1758) in the Shallow Coastal Zones of Gran Canaria in the Eastern Central Atlantic.

The presence of spiny butterfly rays, Gymnura altavela, in waters less than 20 m deep off the Canary Islands shows marked seasonality, with relatively high abundances in the summer and autumn. Large aggregations of sometimes hundreds of individuals, primarily females, appear in specific shallow areas of the archipelago and seem to be associated with the seasonal variation in water temperature. This seasonal pattern of presence or absence in shallow areas suggests that spiny butterfly rays migrate into deeper waters or other unknown areas during the rest of the year. G. altavela shows sexual dimorphism; in our study, females were larger and more abundant than males, with a sex ratio of 1:18.9. The species' estimated asymptotic length, L∞, was 183.75 cm and thus close to the common length reported for the species (200 cm). The von Bertalanffy growth constant (k) oscillated between 0.210 and 0.310 year-1, as similarly described for the species in the Western North Atlantic off the U.S. coast. From June to November, the seawater temperature oscillated between 19 and 24 °C, and massive aggregations of females occurred at 22-24 °C and in a few specific sandy beaches on the islands. Spiny butterfly rays, mostly females, show a preference for aggregating in shallow waters during summertime, probably conditionate to mating or breeding behaviour.

Ametropias in school-age children in Fada N'Gourma (Burkina Faso, Africa).

PURPOSE: To assess epidemiological aspects of refractive errors in school-age children in Burkina Faso (west-central Africa). METHODS: A total of 315 school children (ranging from 6 to 16 years of age and belonging to different ethnic groups) taken at random from two urban schools in eastern Burkina Faso were examined to assess their refractive error, which was determined by non-cycloplegic retinoscopy with optical fogging. The standard Refractive Error Study in Children (RESC) definitions of refractive errors were used: myopia ≤-0.5 D spherical equivalent (SE) in at least one eye, hyperopia ≥2 D SE in at least one eye, astigmatism ≤-0.75 D cylinder in at least one eye, and anisometropia ≥1 D SE difference between the two eyes. RESULTS: Unilateral myopia and bilateral myopia were found in 2.5 and 1%, respectively; unilateral hyperopia in 17.1%, bilateral hyperopia in 8.6%; astigmatism in at least one eye in 11.7%. The highest prevalence value (18.4%) of astigmatism (≤-0.75 D) in at least one eye was found in the Gourmantché ethnic group. The low prevalence of large refractive errors makes visual acuity in these children very good (visual acuity logarithm of the minimum angle of resolution -0.073 ± 0.123 SD). CONCLUSIONS: There was a low prevalence of myopia in these African school children. Clinically significant high hyperopia (≥+2 D SE) was also uncommon. There were no significant differences between the distributions of refractive errors according to gender or ethnicity. With respect to age groups, the prevalences of hyperopia and astigmatism were significantly higher in the younger age groups.

Optical quality and visual discrimination capacity after myopic LASIK with a standard and aspheric ablation profile.

PURPOSE: To determine whether the eye's optical quality is correlated to the visual discrimination capacity of patients treated with LASIK using two different ablation algorithms. METHODS: Visual discrimination was evaluated by the disturbance index under low illumination (Halo v1.0 software, Laboratory of Vision Sciences and Applications) in two groups of patients who underwent LASIK with two different ablation algorithms using the Allegretto Wave Eye-Q 400 Hz laser (WaveLight AG). In the first group (standard group; 30 eyes), corneal ablations were performed with the standard algorithm (preoperative spherical equivalent refraction -3.20±1.70 diopters [D]). In the second group (Q-optimized group; 38 eyes; spherical equivalent refraction -3.40±1.90 D), the ablations were made with the Q-optimized (F-CAT) algorithm. Optical quality of the eye was calculated by the Strehl ratio measured with a double-pass device (OQAS, Visiometrics SL). RESULTS: After LASIK, both the Strehl ratio as well as visual discrimination capacity diminished in both groups, although the changes were significantly greater in the standard group than in the Q-optimized group. CONCLUSIONS: A high correlation was found between the Strehl ratio and the disturbance index in patients who underwent LASIK, regardless of the ablation algorithm applied. Optical and visual deterioration were greater after standard ablation.

[Systemic inflammatory response syndrome associated with use of ticagrelor]. / Síndrome de respuesta inflamatoria sistémica por ticagrelor.

Ticagrelor is anantiplatelet agent which acts through reversible binding to the P2Y12 adenosine-diphosphate receptors. In acute coronary syndromes it has been shown to reduce the risk of major cardiovascular events such as myocardial infarction, stroke and death. Although some hemorrhagic, kidney, liver and respiratory complications have been described in detail with the use of ticagrelor, other less frequent adverse effects are not so well clarified. We report the case of a patient with a systemic inflammatory response syndrome secondary to the use of ticagrelor.

El ticagrelor es un antiagregante plaquetario que actúa a través de la unión reversible a los receptores P2Y12 de la adenosina-difosfato. En el síndrome coronario agudo, ha demostrado reducir el riesgo de eventos cardiovasculares mayores como infarto de miocardio, accidente cerebrovascular y muerte. Si bien se han descripto en detalle ciertas complicaciones hemorrágicas, renales, hepáticas y respiratorias por el uso del ticagrelor, otros efectos adversos menos frecuentes de la droga no han sido adecuadamente esclarecidos. Presentamos el caso de un paciente con un síndrome de respuesta inflamatoria sistémica secundario al uso de ticagrelor.

Differences in the occurrence and abundance of batoids across an oceanic archipelago using complementary data sources: Implications for conservation.

Batoids, distributed from shallow to abyssal depths, are considerably vulnerable to anthropogenic threats. Data deficiencies on the distribution patterns of batoids, however, challenge their effective management and conservation. In this study, we took advantage of the particular geological and geomorphological configuration of the Canary Islands, across an east-to-west gradient in the eastern Atlantic Ocean, to assess whether patterns in the occurrence and abundance of batoids varied between groups of islands (western, central, and eastern). Data were collected from shallow (<40 m, via underwater visual counts and by a local community science program) and deep waters (60-700 m, via ROV deployments). Eleven species of batoids, assessed by the IUCN Red List of Threatened Species, were registered, including three "Critically Endangered" (Aetomylaeus bovinus, Dipturus batis, and Myliobatis aquila), three "Endangered" (Gymnura altavela, Mobula mobular, and Rostroraja alba), two "Vulnerable" (Dasyatis pastinaca and Raja maderenseis), and two "Data Deficient" (Taeniurops grabata and Torpedo marmorata). Also, a "Least Concern" species (Bathytoshia lata) was observed. Overall, batoids were ~1 to 2 orders of magnitude more abundant in the central and eastern islands, relative to the western islands. This pattern was consistent among the three sources of data and for both shallow and deep waters. This study, therefore, shows differences in the abundance of batoids across an oceanic archipelago, likely related to varying insular shelf area, availability of habitats, and proximity to the nearby continental (African) mass. Large variation in population abundances among islands suggests that "whole" archipelago management strategies are unlikely to provide adequate conservation. Instead, management plans should be adjusted individually per island and complemented with focused research to fill data gaps on the spatial use and movements of these iconic species.

Testing a model for excimer laser-ablation rates on corneal shape after refractive surgery.

We have tested whether a recent model [Appl. Phys. Lett.95, 174105 (2009)APPLAB0003-695110.1063/1.3254236] that considers the angular dependence of laser-ablation rates, including reflection losses and geometrical dependence of incident fluence, and the effect of plume absorption can have significant effects for refractive surgery patients. We have developed a mathematical procedure and deduced equations that show that this model can significantly influence postsurgical corneal parameters (radius and asphericity) and, thus, should be considered in ablation algorithms in order to achieve a better emmetropization and an effective correction of eye aberrations.

Influence of interocular differences in the Strehl ratio on binocular summation.

The aim of this work is to determine the influence of interocular differences in retinal image quality on binocular visual performance. We measured the contrast sensitivity function (both monocular and binocular) and we computed binocular summation. Data on retinal image quality were taken from a double-pass device (OQAS, Optical Quality Analysis System; Visiometrics SL. Tarrasa, Spain), providing the Strehl ratio as a parameter to quantify retinal image quality. A total of 28 observers took part in the experiments. Binocular summation for the contrast sensitivity function was found to be significantly (p < 0.001) correlated with interocular differences in the Strehl ratio. The higher the interocular differences in the Strehl ratio, the lower the binocular summation. Binocular summation is less effective as the interocular differences in retinal image increase.

Stereopsis Simulating Small-Aperture Corneal Inlay and Monovision Conditions.

PURPOSE: To analyze stereoscopic vision under a broad range of experimental conditions simulating small-aperture corneal inlay and monovision conditions. METHODS: A total of 10 patients participated in the study. The anisocoria generated by corneal inlays was simulated by using a small-aperture contact lens fitted on the non-dominant eye. Visual acuity, contrast sensitivity function, visual discrimination capacity (halo perception), and stereoacuity tests were performed under natural conditions or when the non-dominant eye wore the small-aperture contact lens under two conditions: induced anisocoria and induced anisocoria combined with monovision (using two add-powers: +0.75 and +1.25 diopters [D]). Stereoscopic vision and binocular summation were analyzed under those experimental conditions and for far, intermediate, and near vision. RESULTS: The results showed a deterioration in stereoacuity with respect to natural conditions, being significant mainly for near and intermediate distances. Results with other visual functions showed a deterioration of the binocular summation and therefore of visual performance, although not in a generalized way for all distances. Binocular visual acuity under the conditions that used the small-aperture contact lens was comparable to that of the natural eye. CONCLUSIONS: The deterioration of stereopsis and other binocular functions found in this study may be acceptable for patients who had this surgical technique because it is similar to the deterioration found in other surgical procedures of emmetropization. [J Refract Surg. 2018;34(7):482-488.].

Síndrome de respuesta inflamatoria sistémica por ticagrelor / Systemic inflammatory response syndrome associated with use of ticagrelor

Resumen El ticagrelor es un antiagregante plaquetario que actúa a través de la unión reversible a los receptores P2Y12 de la adenosina-difosfato. En el síndrome coronario agudo, ha demostrado reducir el riesgo de eventos cardiovasculares mayores como infarto de miocardio, accidente cerebrovascular y muerte. Si bien se han descripto en detalle ciertas complicaciones hemorrágicas, renales, hepáticas y respiratorias por el uso del ticagrelor, otros efectos adversos menos frecuentes de la droga no han sido adecuadamente escla recidos. Presentamos el caso de un paciente con un síndrome de respuesta inflamatoria sistémica secundario al uso de ticagrelor.

Abstract Ticagrelor is anantiplatelet agent which acts through reversible binding to the P2Y12 adenosine-diphosphate recep tors. In acute coronary syndromes it has been shown to reduce the risk of major cardiovascular events such as myocardial infarction, stroke and death. Although some hemorrhagic, kidney, liver and respiratory complications have been described in detail with the use of ticagrelor, other less frequent adverse effects are not so well clari fied. We report the case of a patient with a systemic inflammatory response syndrome secondary to the use of ticagrelor.

Binocular summation and visual function with induced anisocoria and monovision.

The advances in new techniques for correcting presbyopia, such as a small aperture combined with monovision, require an in-depth study of binocular aspects. In this work, we have studied binocular visual performance of 12 subjects after inducing different degrees of anisocoria combined with two different add powers in the non-dominant eye. We have analysed visual performance in terms of the visual-discrimination capacity (a function to evaluate the strength of bothersome halos) and the contrast-sensitivity. The results show a deterioration of the binocular vision when inducing anisocoria and with any add power, with a higher perception of halos, a lower contrast sensitivity and poorer binocular summation of these visual functions on increasing anisocoria. This deterioration is clinically acceptable in the case of low add power, since positive binocular summation is maintained in contrast sensitivity, and visual discrimination is not altered.

Retinal-image quality and night-vision performance after alcohol consumption.

Purpose. To evaluate the influence of alcohol consumption on the retinal-image quality and visual performance under surrounding low-illumination conditions. Methods. A volunteer sample of 67 subjects was analyzed. Optical quality of the eye was evaluated by means of the Strehl ratio, the Objective Scattering Index (OSI), and the tear-film quality. We used the visual disturbance index (VDI) to evaluate visual performance under low-illumination conditions and we measured the pupil size under these conditions. The tear-film volume was also measured. All measurements were made before and after alcohol consumption and patients were classified into two groups depending on their breath alcohol content (BrAC): low-alcohol (BrAC < 0.25 mg/L) and high-alcohol content (BrAC ≥ 0.25 mg/L). Results. The VDI was significantly higher after alcohol consumption: the higher the BrAC, the higher the deterioration of the visual discrimination capacity. The pupil size increased significantly for the high-BrAC group. Parameters evaluating optical quality deteriorated after alcohol consumption. Conclusion. The visual performance under low-illumination conditions and the retinal-image quality were deteriorated after alcohol consumption, especially for the high-alcohol group. Furthermore, some physiological changes were observed under effects for high-alcohol contents, such as an increase in the pupil size and disturbances in the tear film, which deteriorated optical quality.