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Copepods can feed on, and may regulate, the blooms of harmful algae (HA), and may also facilitate dinoflagellate blooms by inducing toxin production and through selective grazing. However, exposure to HA may also cause mortality and reproductive impairment in copepods, with detrimental effects at the population-scale. Here we present the toxin profile of the dinoflagellate, Alexandrium catenella (formerly Alexandrium tamarense), and examine how it affects the survival and reproduction of the cosmopolitan marine copepod, Acartia tonsa. Healthy adult copepods were exposed to mono-specific diets of toxic and non-toxic strains of A. catenella (1119/27 and 1119/19, respectively) and non-toxic Rhodomonas sp. for 10 days alongside unfed controls to examine how their survival was influenced by likely HA bloom conditions. Additional 2-day experiments examined how their egg production rate and hatching success were affected by food deprivation, toxic A. catenella, a non-toxic alternative and a mixture of toxic and non-toxic prey, at high and low concentrations. Survival of A. tonsa declined over the 10-day experiment in all treatments but was not significantly lower in the toxic A. catenella treatment; mortality was only significantly enhanced in the unfed animals, which showed 100% mortality after 9 days. Egg production rates and hatching success from females in the unfed and toxic A. catenella treatments were all significantly lower than values observed in females fed Rhodomonas sp. or non-toxic A. catenella. Animals offered 1,000 μg C L–1 of Rhodomonas sp. and a 50:50 mixture of toxic A. catenella and Rhodomonas sp. produced significantly more eggs than animals fed toxic A. catenella alone. These results were not apparent at prey concentrations of 100 μg C L–1. The percentages of eggs to successfully hatch from females offered mono-specific diets of toxic A. catenella were always close to zero. Collectively, our results indicate that adult female A. tonsa can acquire suffi

Despite evidence for microbial endemism, an understanding of the impact of geological and paleoclimate events on the evolution of regional protist communities remains elusive. Here, we provide insights into the biogeographical history of Antarctic freshwater diatoms, using lacustrine fossils from mid-Miocene and Quaternary Antarctica, and dovetail this dataset with a global inventory of modern freshwater diatom communities. We reveal the existence of a diverse mid-Miocene diatom flora bearing similarities with several former Gondwanan landmasses. Miocene cooling and Plio-Pleistocene glaciations triggered multiple extinction waves, resulting in the selective depauperation of this flora. Although extinction dominated, in situ speciation and new colonizations ultimately shaped the species-poor, yet highly adapted and largely endemic, modern Antarctic diatom flora. Our results provide a more holistic view on the scale of biodiversity turnover in Neogene and Pleistocene Antarctica than the fragmentary perspective offered by macrofossils and underscore the sensitivity of lacustrine microbiota to large-scale climate perturbations.

The IOC-ICES-PICES Harmful Algal Event Database (HAEDAT) was used to describe the diversity and spatiotemporal distribution of harmful algal events along the Atlantic margin of Europe from 1987 - 2018. The majority of events recorded are caused by Diarrhetic Shellfish Toxins (DSTs). These events are recorded annually over a wide geographic area from southern Spain to northern Scotland and Iceland, and are responsible for annual closures of many shellfish harvesting areas. The dominant causative dinoflagellates, members of the morphospecies ‘Dinophysis acuminata complex’ and D. acuta, are common in the waters of the majority of countries affected. There are regional differences in the causative species associated with PST events; the coasts of Spain and Portugal with the dinoflagellates Alexandrium minutum and Gymnodinium catenatum, north west France/south west England/south Ireland with A. minutum, and Scotland/Faroe Islands/Iceland with A. catenella. This can influence the duration and spatial scale of PST events as well as the toxicity of shellfish. The diatom Pseudo-nitzschia australis is the most widespread Domoic Acid (DA) producer, with records coming from Spain, Portugal, France, Ireland and the UK. Amnesic Shellfish Toxins (ASTs) have caused prolonged closures for the scallop fishing industry due to the slow depuration rate of DA. Amendments to EU shellfish hygiene regulations introduced between 2002 and 2005 facilitated end-product testing and sale of adductor muscle. This reduced the impact of ASTs on the scallop fishing industry and thus the number of recorded HAEDAT events. Azaspiracids (AZAs) are the most recent toxin group responsible for events to be characterised in the ICES area. Events associated with AZAs have a discrete distribution with the majority recorded along the west coast of Ireland. Ciguatera Poisoning (CP) has been an emerging issue in the Canary Islands and Madeira since 2004. The majority of aquaculture and wild fish mortality events

Majid Moshirfar,1– 3 James Ellis,4 Daniel Beesley,5 Shannon E McCabe,1,6 Adam Lewis,7 William B West Jnr,4 Yasmyne Ronquillo,1 Phillip Hoopes Snr1 1Hoopes Vision Research Center, Hoopes Vision, Draper, UT, USA; 2John A. Moran Eye Center, Department of Ophthalmology and Visual Sciences, University of Utah, Salt Lake City, UT, USA; 3Utah Lions Eye Bank, Murray, UT, USA; 4University of Utah School of Medicine, Salt Lake City, UT, USA; 5Brigham Young University, Provo, UT, USA; 6Mission Hills Eye Center, Pleasant Hill, CA, USA; 7Kansas City University College of Osteopathic Medicine, Kansas City, MO, USACorrespondence: Majid MoshirfarHoopes Vision Research Center, Hoopes Vision, Draper, UT, USATel +1 801-568-0200Fax +1 801-563-0200Email cornea2020@me.comPurpose: To compare the visual performance of the AcrySof IQ PanOptix trifocal intraocular lens and the TECNIS Symfony extended depth-of-focus lens at near and distance visual ranges.Methods: A total of 146 patients (221 eyes) who underwent phacoemulsification and cataract extraction and received either a PanOptix or Symfony lens from January 2019 to July 2020 were included in the study (83 PanOptix non-toric, 30 PanOptix toric, 70 Symfony non-toric, and 38 Symfony toric). Uncorrected distance (UDVA), uncorrected near (UNVA), and corrected distance (CDVA) visual acuity were assessed at one-day, one-month, and three-months postoperatively. Averages of UDVA, UNVA, and CDVA were taken to evaluate which lens was superior at near and distance visual ranges. Secondary outcome measures including glare, halo, dryness, and problems with night vision were documented at each postoperative visit.Results: At one month postoperatively, the average UNVA was 0.16 ± 0.14 logMAR in the PanOptix group and 0.21 ± 0.14 logMAR in the Symfony group (P=0.007); the average UDVA for the PanOptix group was 0.09 ± 0.13 logMAR compared to the Symfony group at 0.10 ± 0.14 logMAR (P=0.67); and the average CDVA was 0.02 ± 0.05 logMAR in the PanO

Majid Moshirfar,1– 3 Adam L Lewis,4 James H Ellis,5 Shannon E McCabe,1,6 Yasmyne C Ronquillo,1 Phillip C Hoopes Sr1 1Hoopes Vision Research Center, Hoopes Vision, Draper, UT, USA; 2John A. Moran Eye Center, Department of Ophthalmology and Visual Sciences, University of Utah School of Medicine, Salt Lake City, UT, USA; 3Utah Lions Eye Bank, Murray, UT, USA; 4Kansas City University, Kansas City, MO, USA; 5University of Utah School of Medicine, Salt Lake City, UT, USA; 6Mission Hills Eye Center, Pleasant Hill, CA, USACorrespondence: Majid MoshirfarMedical Director Hoopes Vision Research Center, Hoopes Vision, 11820 S. State Street Suite #200, Draper, UT, 84020, USATel +1 801-568-0200Fax +1 801-563-0200Email cornea2020@me.comIntroduction: Retained lens fragments in the anterior chamber following cataract extraction (CE) with phacoemulsification are rare but can lead to significant patient morbidity. Our study aimed to identify risk factors associated with retained lens fragments.Methods: Patients who underwent cataract surgery and subsequently identified to have retained lens fragments in the anterior segment were included. Incidence per year, patient demographics, visual acuity, ocular biometrics, surgical technique, surgeon performing CE, and outcomes were collected retrospectively and compared to a control group.Results: Twenty-four patients were identified with retained lens fragments, with an incidence of 0.10%. The mean age was 76 years ± 6.72 (60– 80) compared to 63 ± 11.41 (22– 86) in the control group (p < 0.001). Patients with UDVA 20/150 or worse experienced a greater average improvement in visual acuity compared to patients with UDVA better than 20/150 (logMAR 0.46 vs logMAR 0.05). The mean intraocular pressures before (CE), after CE but before fragment removal, and following fragment removal were 14 mmHg ± 2.59, 19 mmHg ± 8.20, and 11 mmHg ± 2.75, respectively. Twent

Blooms of harmful algae are increasing globally, yet their impacts on copepods, an important link between primary producers and higher trophic levels, remain largely unknown. Algal toxins may have direct, negative effects on the survival of copepods. They may also indirectly affect copepod survival by deterring feeding and thus decreasing the availability of energy and nutritional resources. Here we present a series of short-term (24 h) experiments in which the cosmopolitan marine copepod, Acartia tonsa, was exposed to a range of concentrations of the toxic dinoflagellate, Alexandrium catenella (strain 1119/27, formerly Alexandrium tamarense), with and without the presence of alternative, non-toxic prey (Rhodomonas sp.). We also present the toxin profile concentrations for A. catenella. The survival and feeding of A. tonsa were not affected across the range of concentrations recorded for A. catenella in the field; increased mortality of A. tonsa was only discernible when A. catenella was present at concentrations that exceed their reported environmental concentrations by two orders of magnitude. The observed lethal median concentration (LC50) for A. tonsa exposed to A. catenella was 12.45 ng STX eq L−1. We demonstrate that A. tonsa is capable of simultaneously ingesting both toxic and non-toxic algae, but increases clearance rates towards non-toxic prey as the proportional abundance of toxic A. catenella increases. The ability to actively select non-toxic algae whilst also ingesting toxic algae suggests that consumption of the latter does not cause physical incapacitation and thus does not affect ingestion in A. tonsa. This work shows that short-term exposure to toxic A. catenella is unlikely to elicit major effects on the grazing or survival of A. tonsa. However, more work is needed to understand the longer-term and sub-lethal effects of toxic algae on marine copepods.

This work proposes a new route to overcome the limits of the thermal poling technique for the creation of second order nonlinearity in conventional silica optical fibers. We prove that it is possible to enhance the nonlinear behavior of periodically poled fibers merging the effects of poling with the nonlinear intrinsic properties of some materials, such as MoS2, which are deposited inside the cladding holes of a twin-hole silica fiber. The optical waves involved in a second harmonic generation process partially overlap inside the thin film of the nonlinear material and exploit its higher third order susceptibility to produce an enhanced SHG., SCOPUS: ar.j, info:eu-repo/semantics/published

Thermal poling, a technique to create permanently effective second-order susceptibility in silica optical fibers, has recently been improved by the discovery of an "induction poling" technique1 and the adoption of liquid electrodes2, allowing for poling fibers of any length and geometry. Nevertheless, the nonlinearity created via thermal poling is always limited by the ooelig;'(3)of the optical fiber material and by the maximum electric field that can be frozen inside the glass. For these reasons research is ongoing to determine routes for further improving the nonlinear effects due to the thermal poling process. In this work, we propose to enhance the effects of the thermal poling by exploiting the intrinsic nonlinear properties of some 2D materials3, which are deposited inside the cladding holes of a twin-hole silica fiber. The materials we focused on are 2D Transition Metal Chalcogenide (2D TMDC) MoS2 and WS2 and the technique adopted to realize the deposition inside the cladding channels of a twin-hole step index silica fiber consists of a thermal decomposition process4 of the precursor ammonium tetrathiomolybdate (NH4)2MoS4 in 6% H2/Ar flow. The technique has allowed us to uniformly coat the two cladding channels for a length of 25 cm with a film nominally consisting in a bi-layer of the 2D materials. A Raman based analysis has been used to test the morphology of the coating. The fiber deposited with 2D materials was later thermally poled and periodically erased via exposure to UV light to reach the QPM condition at a wavelength of 1550 nm. The effective oœ'(2) of the fiber was measured via SHG for both the deposited and the pristine fiber, showing an enhancement of the nonlinearity in favor of the deposited one. The phenomenon can be explained by the exploitation of a higher oœ'(3) seen by the pump wave due to the presence of the 2D layer deposited inside the cladding holes and opens the possibility of exploiting the higher intrinsic material oœ'(2), in case o, SCOPUS: cp.p, info:eu-repo/semantics/published