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1.
Am J Bot ; 111(4): e16321, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38659272

RESUMEN

PREMISE: We studied the 3D morphology of a small, well-preserved cone from the Pennsylvanian Mazon Creek Lagerstätte to characterize its structure and determine its systematic affinity. Previously tentatively assigned to the enigmatic Tetraphyllostrobus, we show that it differs in key respects from that genus as described. METHODS: We systematically compared the new fossil with relevant Paleozoic cone genera and employed advanced imaging techniques, including scanning electron microscopy, Airyscan confocal super-resolution microscopy, optical microscopy, and X-ray microcomputed tomography to visualize and reconstruct the fossil cone in 3D. RESULTS: The analyses demonstrate unequivocally that the sporophylls of the new Mazon Creek cone are arranged in whorls of six and have characters typical of Sphenophyllales, including epidermal cells with undulatory margins and in situ spores assignable to Columinisporites. The combination of characters, including sporophyll arrangement, anatomy, and spore type, supports the establishment of Hexaphyllostrobus kostorhysii gen. et sp. nov. within Sphenophyllales. Furthermore, we show that Tetraphyllostrobus, although originally described as possessing smooth monolete spores, actually possesses Columinisporites-type spores, indicating that it, too, was most likely a sphenophyll. CONCLUSIONS: The recognition of Hexaphyllostrobus contributes to our knowledge of Pennsylvanian sphenophyll diversity, and in particular increases the number of species with in situ Columinisporites-type spores. Attribution of Hexaphyllostrobus to Sphenophyllales calls into question current interpretations of Tetraphyllostrobus suggesting that future research on better-preserved macrofossil material may demonstrate a sphenophyllalean relationship.


Asunto(s)
Fósiles , Fósiles/anatomía & histología , Microtomografía por Rayos X , Microscopía Electrónica de Rastreo , Tracheophyta/anatomía & histología , Tracheophyta/ultraestructura
2.
Ann Bot ; 133(2): 225-260, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38597914

RESUMEN

BACKGROUND: The Chloranthaceae comprise four extant genera (Hedyosmum, Ascarina, Chloranthus and Sarcandra), all with simple flowers. Molecular phylogenetics indicates that the Chloranthaceae diverged very early in angiosperm evolution, although how they are related to eudicots, magnoliids, monocots and Ceratophyllum is uncertain. Fossil pollen similar to that of Ascarina and Hedyosmum has long been recognized in the Early Cretaceous, but over the last four decades evidence of extinct Chloranthaceae based on other types of fossils has expanded dramatically and contributes significantly to understanding the evolution of the family. SCOPE: Studies of fossils from the Cretaceous, especially mesofossils of Early Cretaceous age from Portugal and eastern North America, recognized diverse flowers, fruits, seeds, staminate inflorescences and stamens of extinct chloranthoids. These early chloranthoids include forms related to extant Hedyosmum and also to the Ascarina, Chloranthus and Sarcandra clade. In the Late Cretaceous there are several occurrences of distinctive fossil androecia related to extant Chloranthus. The rich and still expanding Cretaceous record of Chloranthaceae contrasts with a very sparse Cenozoic record, emphasizing that the four extant genera are likely to be relictual, although speciation within the genera might have occurred in relatively recent times. In this study, we describe three new genera of Early Cretaceous chloranthoids and summarize current knowledge on the extinct diversity of the group. CONCLUSIONS: The evolutionary lineage that includes extant Chloranthaceae is diverse and abundantly represented in Early Cretaceous mesofossil floras that provide some of the earliest evidence of angiosperm reproductive structures. Extinct chloranthoids, some of which are clearly in the Chloranthaceae crown group, fill some of the morphological gaps that currently separate the extant genera, help to illuminate how some of the unusual features of extant Chloranthaceae evolved and suggest that Chloranthaceae are of disproportionate importance for a more refined understanding of ecology and phylogeny of early angiosperm diversification.


Asunto(s)
Frutas , Magnoliopsida , Semillas , Ecología , Flores , Fósiles , Magnoliopsida/genética
3.
Am J Bot ; 111(2): e16268, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38050806

RESUMEN

PREMISE: Fossil seeds recovered from the Early Cretaceous of Mongolia and Inner Mongolia, China, are described and assigned to Mongolitria gen. nov., a new genus of gymnosperm seed. METHODS: Abundant lignitized seeds along with compression specimens isolated from the matrix were studied using a combination of scanning electron microscopy, anatomical sectioning, light microscopy, synchrotron radiation X-ray microtomography, and cuticle preparations. A single permineralized seed was examined by light microscopy of cellulose acetate peels and X-ray microtomography. RESULTS: Two species are recognized, Mongolitria friisae sp. nov. and Mongolitria exesum sp. nov. Both seeds are orthotropous with a short apical micropyle and a small, basal, circular attachment scar. The thick sclerenchymatous integument has a consistently three-parted organization and about 20 conspicuous longitudinal ribs on the surface. Mongolitria exesum differs from M. friisae primarily in its much larger size and thicker seed coat, which also preserves clear evidence of insect damage. CONCLUSIONS: Mongolitria is similar to other fossil seeds that have been assigned to Cycadales, but displays a unique combination of characters not found in any living or extinct cycadaceous plant, leaving its higher-level systematic affinities uncertain. Germination apparently involved splitting of the integument into three valves. Mongolitria was prominent among the plant parts accumulating in peat swamps in eastern Asia during the Early Cretaceous.


Asunto(s)
Evolución Biológica , Semillas , Microscopía Electrónica de Rastreo , China , Cycadopsida , Fósiles , Filogenia
4.
New Phytol ; 233(5): 2310-2322, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34981832

RESUMEN

Lycopodiaceae are one of three surviving families of lycopsids, a lineage of vascular plants with a fossil history dating to at least the Early Devonian or perhaps the Late Silurian (c. 415 Ma). Many fossils have been linked to crown Lycopodiaceae, but the lack of well-preserved material has hindered definitive recognition of this group in the paleobotanical record. New, exceptionally well-preserved permineralized lycopsid fossils from the Early Cretaceous (125.6 ± 1.0 Ma) of Inner Mongolia, China, were examined in detail using acetate peel and micro-computed tomography techniques. The anatomy of extant Lycopodiaceae was analyzed for comparison using fluorescence microscopy. Phylogenetic relationships of the new fossil to extant Lycopodiaceae were evaluated using parsimony and maximum likelihood analyses. Lycopodicaulis oellgaardii gen. et sp. nov. provides the earliest unequivocal and best-documented evidence of crown Lycopodiaceae and Lycopodioideae, based on anatomically-preserved fossil material. Recognition of Lycopodicaulis in Asia during the Early Cretaceous indicates the presence of crown Lycopodiaceae at this time, and striking similarities of stem anatomy with extant species provide a framework for the understanding of the interaction of branching and vascular anatomy in crown-group lycopsids.


Asunto(s)
Fósiles , Lycopodiaceae , Filogenia , Evolución Biológica , China , Lycopodiaceae/clasificación , Microtomografía por Rayos X
5.
Sci Rep ; 11(1): 18388, 2021 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-34526644

RESUMEN

New Caledonia was, until recently, considered an old continental island harbouring a rich biota with outstanding Gondwanan relicts. However, deep marine sedimentation and tectonic evidence suggest complete submergence of the island during the latest Cretaceous to the Paleocene. Molecular phylogenies provide evidence for some deeply-diverging clades that may predate the Eocene and abundant post-Oligocene colonisation events. Extinction and colonization biases, as well as survival of some groups in refuges on neighbouring paleo-islands, may have obscured biogeographic trends over long time scales. Fossil data are therefore crucial for understanding the history of the New Caledonian biota, but occurrences are sparse and have received only limited attention. Here we describe five exceptional fossil assemblages that provide important new insights into New Caledonia's terrestrial paleobiota from three key time intervals: prior to the submersion of the island, following re-emergence, and prior to Pleistocene climatic shifts. These will be of major importance for elucidating changes in New Caledonia's floristic composition over time.

6.
Am J Bot ; 108(8): 1483-1499, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34458982

RESUMEN

PREMISE: Seed cones of extant Pinaceae exhibit two mechanisms of seed release. In "flexers" the cone scales remain attached to the central axis, while flexing and separating from each other to release the seeds. In "shedders" scales are shed from the axis, with the seeds either remaining attached to the scale or becoming detached. The early fossil history of Pinaceae from the Jurassic to Early Cretaceous is dominated by flexing seed cones, while the systematic information provided by shedding fossil cones has been overlooked and rarely integrated with data based on compression and permineralized specimens. We describe the earliest and best-documented evidence of a "shedder" seed cone from the Aptian-Albian of Mongolia. METHODS: Lignite samples from Tevshiin Govi locality were disaggregated in water, washed, and dried in air. Fossils were compared to material of extant Pinaceae using LM and CT scans. RESULTS: Lepidocasus mellonae gen. et sp. nov. is characterized by a seed cone that disarticulated at maturity and shed obovate bract-scale complexes that have a distinctive ribbed surface and an abaxial surface covered with abundant trichomes. The ovuliferous scale has ca. 30-40 resin canals, but only scarce xylem near the attachment to the cone axis. Resin vesicles are present in the seed integument. Phylogenetic analysis places Lepidocasus as sister to extant Cedrus within the abietoid grade. CONCLUSIONS: The exquisite preservation of the trichomes in L. mellonae raises questions about their potential ecological function in the cones of fossil and living Pinaceae. Lepidocasus mellonae also shows that a shedding dispersal syndrome, a feature that has often been overlooked, evolved early in the history of Pinaceae during the Early Cretaceous.


Asunto(s)
Pinaceae , Fósiles , Mongolia , Filogenia , Semillas
7.
Nature ; 594(7862): 223-226, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34040260

RESUMEN

The second integument of the angiosperm ovule is unique among seed plants, with developmental genetics that are distinct from those of the inner integument1. Understanding how the second integument should be compared to structures in other seed plants is therefore crucial to resolving the long-standing question of the origin of angiosperms2-6. Attention has focused on several extinct plants with recurved cupules that are reminiscent of the anatropous organization of the basic bitegmic ovules of angiosperms1-6, but interpretations have been hampered by inadequate information on the relevant fossils. Here we describe abundant exceptionally well-preserved recurved cupules from a newly discovered silicified peat dating to the Early Cretaceous epoch (around 125.6 million years ago) in Inner Mongolia, China. The new material, combined with re-examination of potentially related fossils, indicates that the recurved cupules of several groups of Mesozoic plants are all fundamentally comparable, and that their structure is consistent with the recurved form and development of the second integument in the bitegmic anatropous ovules of angiosperms. Recognition of these angiosperm relatives (angiophytes) provides a partial answer to the question of angiosperm origins, will help to focus future work on seed plant phylogenetics and has important implications for ideas on the origin of the angiosperm carpel.


Asunto(s)
Evolución Biológica , Extinción Biológica , Fósiles , Integumento Común/anatomía & histología , Magnoliopsida/anatomía & histología , Óvulo Vegetal/anatomía & histología , China , Historia Antigua , Magnoliopsida/ultraestructura , Mongolia , Óvulo Vegetal/ultraestructura , Filogenia
8.
Plant Divers ; 42(4): 319-322, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33094203
9.
Proc Natl Acad Sci U S A ; 117(18): 9674-9676, 2020 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-32303652
10.
PLoS One ; 15(1): e0226779, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31940374

RESUMEN

Previously unrecognized anatomical features of the cone scales of the enigmatic Early Cretaceous conifer Krassilovia mongolica include the presence of transversely oriented paracytic stomata, which is unusual for all other extinct and extant conifers. Identical stomata are present on co-occurring broad, linear, multiveined leaves assigned to Podozamites harrisii, providing evidence that K. mongolica and P. harrisii are the seed cones and leaves of the same extinct plant. Phylogenetic analyses of the relationships of the reconstructed Krassilovia plant place it in an informal clade that we name the Krassilovia Clade, which also includes Swedenborgia cryptomerioides-Podozamites schenkii, and Cycadocarpidium erdmanni-Podozamites schenkii. All three of these plants have linear leaves that are relatively broad compared to most living conifers, and that are also multiveined with transversely oriented paracytic stomata. We propose that these may be general features of the Krassilovia Clade. Paracytic stomata, and other features of this new group, recall features of extant and fossil Gnetales, raising questions about the phylogenetic homogeneity of the conifer clade similar to those raised by phylogenetic analyses of molecular data.


Asunto(s)
Tracheophyta/anatomía & histología , Filogenia , Hojas de la Planta/anatomía & histología , Semillas/anatomía & histología , Terminología como Asunto , Tracheophyta/clasificación
13.
Clin Pract Cases Emerg Med ; 3(1): 47-50, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30775664

RESUMEN

We report a case of acute necrotizing eosinophilic myocarditis (ANEM) secondary to drug rash with eosinophilia and systemic symptoms (DRESS) related to administration of minocycline. Myocarditis is a rare complication of DRESS and can manifest as either a self-limited hypersensitivity myocarditis or as the frequently fatal ANEM. Due to the high morbidity and mortality caused by this disease, emergency physicians should be aware of the potential of ANEM in patients with history of DRESS and new-onset cardiac dysfunction. This case reviews the clinical presentation and management of ANEM and the potential role of extracorporeal membrane oxygenation use in the emergency department.

14.
Am J Bot ; 105(8): 1369-1388, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-30080239

RESUMEN

PREMISE OF THE STUDY: Exotestal seeds with characters that indicate relationship to extant Austrobaileyales and Nymphaeales are abundant in Early Cretaceous sediments from Portugal and eastern North America, but their variety and unique features provide evidence of extensive extinct diversity among early angiosperms. METHODS: The fossils were extracted from Early Cretaceous sediments from Virginia and Maryland, United States, by sieving in water. After cleaning with HF, HCl and water, they were examined using SEM and SRXTM and compared to seeds of extant and fossil angiosperms. KEY RESULTS: A new genus, Tanispermum gen. nov., with four species (T. hopewellense sp. nov., T. marylandense sp. nov., T. drewriense sp. nov., and T. antiquum sp. nov.) is recognized. Relationship with extant Austrobaileyales and Nymphaeales is indicated by an exotesta of tall palisade sclerenchyma with undulate anticlinal walls forming a jigsaw puzzle-like surface pattern. However, seeds of Tanispermum differ from those of Austrobaileyales and Nymphaeales in their hemi-orthotropous-hemi-anatropous organization. Attempts to place Tanispermum in a phylogenetic context confront a variety of problems, including lack of information on other parts of these extinct plants. CONCLUSIONS: The discovery highlights the extent to which the morphology of extant angiosperms is not representative of the diversity that once existed among early-diverging members of the group. The relictual nature of extant taxa near the base of the angiosperm tree greatly complicates the reconstruction of ancestral character states and emphasizes the need for focused paleobotanical studies to elucidate the extinct diversity that existed early in angiosperm evolution.


Asunto(s)
Fósiles/ultraestructura , Magnoliopsida/genética , Semillas/ultraestructura , Magnoliopsida/ultraestructura , Maryland , Virginia
15.
J Med Toxicol ; 14(3): 242-247, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29845507

RESUMEN

INTRODUCTION: Telemedicine and its use in medical toxicology have existed for some time. There are varied definitions, but existing ones center on using currently available forms of audio, video, and internet communications to provide "real-time" patient care. Definitions have historically limited reimbursement but recently expanded CMS guidelines have improved this. Here we describe our experience with telemedicine and reimbursement. METHODS: A retrospective study was conducted of all toxicology and billing reimbursement for fiscal year 2016 for a solo Medical Toxicology service. Clinical identifiers were used to match telemedicine consults to hospital financial databases and then removed. Telemedicine consults were isolated, quantified, and described. RESULTS: A total of 16 telemedicine consults were conducted. Average age was 37.2 (range 2 months-82 years). Gender was evenly split at 8:8. Twenty-five percent were pediatric consultations. The main purposes of consultation were as follows: diagnosis and disease management in drug ingestion, triage assistance, clearance consults, antidote administration, and buprenorphine induction. At the time of the work, $1896.00 for 9.3 h of teletoxicology services was reimbursed equating to an hourly reimbursement rate of $203.90/h. LIMITATIONS: Our data was obtained from a toxicology practice with a surrounding infrastructure dedicated to telemedicine. All sites may not have this robust ancillary support. Furthermore, not all states have reimbursement mandates such as New York State. CONCLUSION: To our knowledge, this is the first published work describing pilot data in the successful reimbursement for Medical Toxicology services delivered via telemedicine. Toxicology via telemedicine represents a great opportunity for advancing the practice of toxicology in an economically feasible way, particularly in rural or underserved areas.


Asunto(s)
Atención a la Salud/economía , Atención a la Salud/métodos , Reembolso de Seguro de Salud , Telemedicina/economía , Telemedicina/métodos , Toxicología/economía , Toxicología/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antídotos/uso terapéutico , Costos y Análisis de Costo , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Proyectos Piloto , Intoxicación/diagnóstico , Intoxicación/tratamiento farmacológico , Derivación y Consulta , Estudios Retrospectivos , Flujo de Trabajo , Adulto Joven
16.
West J Emerg Med ; 18(5): 821-829, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28874933

RESUMEN

INTRODUCTION: The Choosing Wisely campaign currently recommends avoiding computed tomography (CT) of the head in low-risk emergency department (ED) patients with minor head injury, based on validated decision rules. However, the degree of adherence to this guideline in clinical practice is unknown. The objective of this study was to evaluate adherence to the Choosing Wisely campaign's recommendations regarding head CT imaging of patients with minor head injury in the ED. METHODS: We conducted a retrospective cohort study of adult ED patients at a Level I trauma center. Patients aged ≥ 18 years who presented to the ED with minor head injury were identified via International Classification of Diseases, 9th Revision, Clinical Modification codes. Medical record abstraction was conducted to determine the presence of clinical symptoms of the NEXUS II criteria, medical resource use, and head CT findings. We used descriptive statistics to characterize the study sample, and proportions were used to quantify guidelines adherence. RESULTS: A total of 489 subjects met inclusion criteria. ED providers appropriately applied the Choosing Wisely criteria for 75.5% of patients, obtaining head CTs when indicated by the NEXUS II rule (41.5%), and not obtaining head CTs when the NEXUS II criteria were not met (34.0%). However, ED providers obtained non-indicated CTs in 23.1% of patients. Less than 2% of the sample did not receive a head CT when imaging was indicated by NEXUS II. CONCLUSION: ED providers in our sample had variable adherence to the Choosing Wisely head-CT recommendation, especially for patients who did not meet the NEXUS II criteria.


Asunto(s)
Traumatismos Craneocerebrales/diagnóstico por imagen , Técnicas de Apoyo para la Decisión , Anciano , Protocolos Clínicos , Toma de Decisiones , Servicio de Urgencia en Hospital , Femenino , Adhesión a Directriz , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
17.
Proc Natl Acad Sci U S A ; 114(12): E2385-E2391, 2017 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-28265050

RESUMEN

The origins of the five groups of living seed plants, including the single relictual species Ginkgo biloba, are poorly understood, in large part because of very imperfect knowledge of extinct seed plant diversity. Here we describe well-preserved material from the Early Cretaceous of Mongolia of the previously enigmatic Mesozoic seed plant reproductive structure Umaltolepis, which has been presumed to be a ginkgophyte. Abundant new material shows that Umaltolepis is a seed-bearing cupule that was borne on a stalk at the tip of a short shoot. Each cupule is umbrella-like with a central column that bears a thick, resinous, four-lobed outer covering, which opens from below. Four, pendulous, winged seeds are attached to the upper part of the column and are enclosed by the cupule. Evidence from morphology, anatomy, and field association suggests that the short shoots bore simple, elongate Pseudotorellia leaves that have similar venation and resin ducts to leaves of living GinkgoUmaltolepis seed-bearing structures are very different from those of Ginkgo but very similar to fossils described previously as Vladimaria. Umaltolepis and Vladimaria do not closely resemble the seed-bearing structures of any living or extinct plant, but are comparable in some respects to those of certain Peltaspermales and Umkomasiales (corystosperms). Vegetative similarities of the Umaltolepis plant to Ginkgo, and reproductive similarities to extinct peltasperms and corystosperms, support previous ideas that Ginkgo may be the last survivor of a once highly diverse group of extinct plants, several of which exhibited various degrees of ovule enclosure.


Asunto(s)
Ginkgo biloba/anatomía & histología , Plantas/anatomía & histología , Semillas/anatomía & histología , Fósiles/anatomía & histología , Ginkgo biloba/clasificación , Plantas/clasificación , Semillas/clasificación
18.
Nat Plants ; 3: 17015, 2017 03 03.
Artículo en Inglés | MEDLINE | ID: mdl-28260783

RESUMEN

Angiosperms (flowering plants) are the most diverse of all major lineages of land plants and the dominant autotrophs in most terrestrial ecosystems. Their evolutionary and ecological appearance is therefore of considerable interest and has significant implications for understanding patterns of diversification in other lineages, including insects and other animals. More than half a century ago, influential reviews showed that while angiosperms are richly represented in sediments of Late Cretaceous and younger ages, there are no reliable records of angiosperms from pre-Cretaceous rocks. The extensive new macrofossil, mesofossil, and microfossil data that have accumulated since have confirmed and reinforced this pattern. Recently, however, molecular dating methods have raised the possibility that angiosperms may have existed much earlier, and there have been scattered reports of putative angiosperms from Triassic and Jurassic rocks. Critical assessment of these reports shows that, so far, none provide unequivocal evidence of pre-Cretaceous angiosperms. Angiosperms may ultimately be recognized from Jurassic or earlier rocks, but credible palaeobotanical evidence will require unambiguous documentation of the diagnostic structural features that separate angiosperms from other groups of extant and extinct seed plants.


Asunto(s)
Evolución Biológica , Fósiles/anatomía & histología , Magnoliopsida/clasificación , Evolución Molecular , Magnoliopsida/anatomía & histología , Magnoliopsida/genética , Filogenia
19.
Am J Bot ; 104(9): 1370-1381, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-29885232

RESUMEN

PREMISE OF THE STUDY: Hymenophyllaceae ("filmy ferns") are a widely distributed group of predominantly tropical, epiphytic ferns that also include some temperate and terrestrial species. Hymenophyllaceae are one of the earliest-diverging lineages within leptosporangiate ferns, but their fossil record is sparse, most likely because of their low fossilization potential and commonly poor preservation of their delicate, membranaceous fronds. A new species of unequivocal fossil Hymenophyllaceae, Hymenophyllum iwatsukii sp. nov., is described from the Early Cretaceous of Mongolia based on abundant and exceptionally well-preserved material. METHODS: Bulk lignite samples collected from Tevshiin Govi and Tugrug localities in Mongolia, were disaggregated in water, cleaned with hydrochloric and hydrofluoric acids, washed, and dried in air. Fossils were examined and compared to material of extant Hymenophyllaceae using LM and SEM. KEY RESULTS: The fossil fern specimens are assigned to the Hymenophyllaceae based on their membranaceous laminae with marginal sori that have sessile to short-stalked sporangia with oblique, complete annuli, and trilete, tetrahedral-globose spores. Within the family, the fossil material is assigned to the extant genus Hymenophyllum on the basis of bivalvate indusia and short, included receptacles. CONCLUSIONS: Hymenophyllum iwatsukii was likely an epiphyte based on the sedimentary environment in which the fossils are preserved, the associated fossil flora, and the growth habit of extant species of Hymenophyllum. The new fossil species underlines the extent to which morphological characters in Hymenophyllum have been conserved despite significant tectonic, climatic, ecological, and floristic changes since the Early Cretaceous.


Asunto(s)
Helechos/ultraestructura , Fósiles/anatomía & histología
20.
Ann Emerg Med ; 69(2): 227-240, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27998625

RESUMEN

STUDY OBJECTIVE: To identify critical emergency medicine-focused firearm injury research questions and develop an evidence-based research agenda. METHODS: National content experts were recruited to a technical advisory group for the American College of Emergency Physicians Research Committee. Nominal group technique was used to identify research questions by consensus. The technical advisory group decided to focus on 5 widely accepted categorizations of firearm injury. Subgroups conducted literature reviews on each topic and developed preliminary lists of emergency medicine-relevant research questions. In-person meetings and conference calls were held to iteratively refine the extensive list of research questions, following nominal group technique guidelines. Feedback from external stakeholders was reviewed and integrated. RESULTS: Fifty-nine final emergency medicine-relevant research questions were identified, including questions that cut across all firearm injury topics and questions specific to self-directed violence (suicide and attempted suicide), intimate partner violence, peer (nonpartner) violence, mass violence, and unintentional ("accidental") injury. Some questions could be addressed through research conducted in emergency departments; others would require work in other settings. CONCLUSION: The technical advisory group identified key emergency medicine-relevant firearm injury research questions. Emergency medicine-specific data are limited for most of these questions. Funders and researchers should consider increasing their attention to firearm injury prevention and control, particularly to the questions identified here and in other recently developed research agendas.


Asunto(s)
Medicina de Emergencia , Investigación sobre Servicios de Salud , Heridas por Arma de Fuego/prevención & control , Comités Consultivos , Consenso , Armas de Fuego , Humanos , Factores de Riesgo , Prevención del Suicidio
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