351 research outputs found

    Tubiclavoides striatum gen. nov et sp nov (Cnidaria : Hydrozoa) a new bathyal hydroid from the Gulf of Cadiz, north-east Atlantic Ocean

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    Tubiclavoides striatum, a new species of an athecate hydroid, was found on mud volcanoes, inactive carbonate clumneys, and cold-water coral stands in the Gulf of Cadiz (south-western Iberian Peninsula, Atlantic Ocean). The new family Tubiclavoididae and the new genus Tubiclavoides are proposed to accommodate the new species. The new hydroid is characterized by scattered filiform tentacles, sporosacs developing among the tentacles and hydrocauli covered with striated perisarc, often subdivided into imbricating cones. A full description and illustrations are provided, as well as some notes on the ecology and distribution of the new species

    DNA Sequence-Mediated, Evolutionarily Rapid Redistribution of Meiotic Recombination Hotspots: Commentary on Genetics 182: 459–469 and Genetics 187: 385–396

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    Hotspots regulate the position and frequency of Spo11 (Rec12)-initiated meiotic recombination, but paradoxically they are suicidal and are somehow resurrected elsewhere in the genome. After the DNA sequence-dependent activation of hotspots was discovered in fission yeast, nearly two decades elapsed before the key realizations that (A) DNA site-dependent regulation is broadly conserved and (B) individual eukaryotes have multiple different DNA sequence motifs that activate hotspots. From our perspective, such findings provide a conceptually straightforward solution to the hotspot paradox and can explain other, seemingly complex features of meiotic recombination. We describe how a small number of single-base-pair substitutions can generate hotspots de novo and dramatically alter their distribution in the genome. This model also shows how equilibrium rate kinetics could maintain the presence of hotspots over evolutionary timescales, without strong selective pressures invoked previously, and explains why hotspots localize preferentially to intergenic regions and introns. The model is robust enough to account for all hotspots of humans and chimpanzees repositioned since their divergence from the latest common ancestor

    Hydrozoa

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    The European list was derived from URMO which was edited by W. Vervoort. S.D. Cairns provided the list of hydrocorals and P. Schuchert provided additions the list of hydroids

    Hundreds of genetic barcodes of the species-rich hydroid superfamily Plumularioidea (Cnidaria, Medusozoa) provide a guide toward more reliable taxonomy

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    Marine hydroids are important benthic components of shallow and deep waters worldwide, but their taxonomy is controversial because diagnostic morphological characters to categorize taxa are limited. Their genetic relationships are also little investigated. We tested taxonomic hypotheses within the highly speciose superfamily Plumularioidea by integrating a classical morphological approach with DNA barcoding of the 16S and COI mitochondrial markers for 659 and 196 specimens of Plumularioidea, respectively. Adding Genbank sequences, we inferred systematic relationships among 1,114 plumularioids, corresponding to 123 nominal species and 17 novel morphospecies in five families of Plumularioidea. We found considerable inconsistencies in the systematics of nominal families, genera and species. The families Kirchenpaueriidae and Plumulariidae were polyphyletic and the Halopterididae paraphyletic. Most genera of Plumularioidea are not monophyletic. Species diversity is considerably underestimated. Within our study, at least 10% of the morphologically-distinctive morphospecies are undescribed, and about 40% of the overall species richness is represented by cryptic species. Convergent evolution and morphological plasticity therefore blur systematic relationships. Additionally, cryptic taxa occur frequently in sympatry or parapatry, complicating correspondence with type material of described species. Sometimes conspecificity of different morphotypes was found. The taxonomy of hydroids requires continued comprehensive revision.This work relied on several hydrozoan samples collected from various sites, with the aid of many people. Supplementary Table S1 refers many of the people involved in the collection and/or preservation of the samples. C.J.M. acknowledges his great buddy-divers Jaime N.-Ruiz (CIMAR, Univ. Costa Rica), Axel Calderon, Nathaniel Chu, Eleni Petrou (STRI, Smiths. Inst.), Hanae Spathias, Karen Koltes (at the Belize station, Smith. Inst.), Freya Sommer (Hopkins Marine Station), Remilson Ferreira ('Costa Norte', Sao Tome), Frederico Cardigos (DOP, Univ. Azores) and others that assisted the dives. C.J.M. also acknowledges Rita Castillo (CIMAR, Univ. Costa Rica), Plinio Gondola, Ligia Calderon, Laura Geyer, Maria Castillo (STRI, Smiths. Inst.), Gregory Ruiz (SERC, Smiths. Inst.), Paul Greenhall, William Keel (MSC, Smith. Inst.), Manuel Enes, Valentina Matos (IMAR/DOP, Univ. Azores), Filipe Porteiro, Joao Goncalves (OKEANOS/IMAR, Univ. Azores), Marina Cunha, Ascensao Ravara (CESAM, Univ. Aveiro), Shirley Pomponi (Harbor Branch, Florida Atlantic Univ.), Estrela Matilde (Fundacao Principe Trust), Monica Albuquerque, Ines Tojeira (EMEPC), Diana Carvalho (Nat. Mus. Nat. Hist., Lisbon) and many others colleagues that facilitated the morphologic classifications and deposition of the samples. Peter Schuchert (Mus. d'Hist. Nat. Geneve) kindly provided some DNA extractes. Todd Kincaid and his team of GUE divers (Project Baseline - Azores) collected valuable samples from unusual depths. Joana Boavida (CIIMAR, Univ. Algarve) facilitated some samples of the 'DeepReefs' project. Jim Drewery (Marine Scotland Science Inst.) also provided few samples. Dale Calder (Royal Ontario Museum) provided some bibliography to C.J.M. and discussed/resolved some dubios taxonomic classifications. Colleagues at the L.A.B. (NMNH, Smith. Inst.) were very supportive. The APC fees for open access publication were supported by a program of the Regional Government of the Azores ("Apoio ao funcionamento e gestao dos centros de I&D regionais: 2018 - DRCT-medida 1

    The Ursinus Weekly, October 22, 1951

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    Seniors elect Paul Doughty new president • Full day planned for return of Old Timers • Weekly staff is enlarged by new members • Y retreat termed success; Varied program enjoyed • Chem group plans trip to exhibition • Ruby pictures slated • FTA plans roast for all members • Red Cross plans first aid, life saving courses for students • \u2755 show features night club life • 4 members added to Lantern staff • Chairmen named for junior events • Jobs offered • Scientific phenomena featured in magic show October 31 • Y cabinet makes new appointments • F&M demands no pre-game visitation • Editorials: New topics needed; British bar allusions • Letters to the editor • Alumni • Engagement • Identical twins revolt against heredity laws • Cutting classes requires skillful maneuvering and also fat purse • Ruth Reed goes to Venezuela for Y summer work • Ursinus meets Wagner on Homecoming day • Spying by Happy Chandler helped Centre top Harvard • Belles are victors in last 60 seconds as Rittenhouse scores winning goal • Glock paces Ursinus scorers • Curtis takes lead in interdorm loop • Bakermen lose to Rutgers, 5-4 • Grizzlies beat Swarthmore to gain football holiday • Swarthmore defeated in J.V. hockey, 5-4 • Pre-med society changes constitution; Election slated • WSGA secures dates for activities meetings during year • Debating explained • Meistersingers practice • Pre-legal drive opens • Chess club loseshttps://digitalcommons.ursinus.edu/weekly/1524/thumbnail.jp

    Driven by speculation, not by impact - the effects of plastic on fish species.

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    Plastic products have facilitated the daily lives of an exponentially increasing world population for over 70 years, whilst inadvertently creating one of the most topical environmental issues of the 21st Century: the plastic pollution crisis. Since the mid-20th Century, plastic production has expanded continuously to global production levels of over 350 million tons in 2018 (Thompson et al. 2009; Plastics Europe, 2019). Articles surrounding the presence and impacts of plastic pollution on aquatic animals including fish species have become a regular occurrence on media platforms (Kramm et al. 2018) and scientific publications (Henderson & Green, 2020); however, while iconic pictures of individual fish and other taxa with variously attached or ingested plastics might make headlines, they do not of themselves prove impacts, absolute or relative, at population levels

    Anatomic segmentectomy for stage I non–small-cell lung cancer: Comparison of video-assisted thoracic surgery versus open approach

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    ObjectivesAnatomic segmentectomy is increasingly being considered as a means of achieving an R0 resection for peripheral, small, stage I non–small-cell lung cancer. In the current study, we compare the results of video-assisted thoracic surgery (n = 104) versus open (n = 121) segmentectomy in the treatment of stage I non–small-cell lung cancer.MethodsA total of 225 consecutive anatomic segmentectomies were performed for stage IA (n = 138) or IB (n = 87) non–small-cell lung cancer from 2002 to 2007. Primary outcome variables included hospital course, complications, mortality, recurrence, and survival. Statistical comparisons were performed utilizing the t test and Fisher exact test. The probability of overall and recurrence-free survival was estimated with the Kaplan-Meier method, with significance being estimated by the log-rank test.ResultsMean age (69.9 years) and gender distribution were similar between the video-assisted thoracic surgery and open groups. Average tumor size was 2.3 cm (2.1 cm video-assisted thoracic surgery; 2.4 cm open). Mean follow-up was 16.2 (video-assisted thoracic surgery) and 28.2 (open) months. There were 2 perioperative deaths (2/225; 0.9%), both in the open group. Video-assisted thoracic surgery segmentectomy was associated with decreased length of stay (5 vs 7 days, P < .001) and pulmonary complications (15.4% vs 29.8%, P = .012) compared with open segmentectomy. Overall mortality, complications, local and systemic recurrence, and survival were similar between video-assisted thoracic surgery and open segmentectomy groups.ConclusionsVideo-assisted thoracic surgery segmentectomy can be performed with acceptable morbidity, mortality, recurrence, and survival. The video-assisted thoracic surgery approach affords a shorter length of stay and fewer postoperative pulmonary complications compared with open techniques. The potential benefits and limitations of segmentectomy will need to be further evaluated by prospective, randomized trials

    The accumulation of microplastic pollution in a commercially important fishing ground

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    The Irish Sea is an important area for Norway Lobster Nephrops norvegicus fisheries, which are the most valuable fishing resource in the UK. Norway lobster are known to ingest microplastic pollution present in the sediment and have displayed reduced body mass when exposed to microplastic pollution. Here, we identified microplastic pollution in the Irish Sea fishing grounds through analysis of 24 sediment samples from four sites of differing proximity to the Western Irish Sea Gyre in both 2016 and 2019. We used µFTIR spectroscopy to identify seven polymer types, and a total of 77 microplastics consisting of fibres and fragments. The mean microplastics per gram of sediment ranged from 0.13 to 0.49 and 0 to 1.17 MP/g in 2016 and 2019, respectively. There were no differences in the microplastic counts across years, and there was no correlation of microplastic counts with proximity to the Western Irish Sea Gyre. Considering the consistently high microplastic abundance found in the Irish Sea, and the propensity of N. norvegicus to ingest and be negatively impacted by them, we suggest microplastic pollution levels in the Irish Sea may have adverse impacts on N. norvegicus and negative implications for fishery sustainability in the future

    Defining sustainable and precautionary harvest rates for data-limited short-lived stocks: a case study of sprat (Sprattus sprattus) in the English Channel2023

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    Publication history: Accepted - 3 March 2023; Published - 17 April 2023.Empirical harvest control rules set catch advice based on observed indicators and are increasingly being used worldwide to manage fish stocks that lack formal assessments of stock and exploitation status. Within the International Council for the Exploration of the Sea, trend-based rules that adjust advice according to recent survey observations have been adopted; however, there is increasing evidence that such rules do not work well for short-lived pelagic species that can exhibit large inter-annual fluctuations in stock size. Constant harvest rates, removing a fixed proportion of observed biomass index, have been proposed as a suitable strategy for managing short-lived species. Unknown survey catchability has, however, remained a barrier to reliance on their application on these stocks in the past. We apply simulation testing to define a robust, sustainable constant harvest rate for a data-limited short-lived stock, using the English Channel sprat as a case study. By conditioning a management strategy evaluation framework based on existing and borrowed life-history parameters and precautionary considerations, we test and show that a constant harvest rate outperforms trend-based catch rules, maximizing yields while reducing risks of stock overexploitation, and conclude an 8.6% constant harvest rate provides sufficiently precautionary catch advice for this stock.Part of this work was funded by the UK Department of Environment, Food and Rural Affairs
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