160 research outputs found
Anastomose carotidobasilar e persistência da artéria hipoglossa primitiva: registro de um caso
Picturing the nation : The Celtic periphery as discursive other in the archaeological displays of the museum of Scotland
Using the archaeological displays at the Museum of Scotland in Edinburgh, this paper examines the exhibition as a site of identity creation through the negotiations between categories of same and Other. Through an analysis of the poetics of display, the paper argues that the exhibition constructs a particular relationship between the Celtic Fringe and Scottish National identity that draws upon the historical discourses of the Highlands and Islands of Scotland as a place and a time \u27apart\u27. This will be shown to have implications for the display of archaeological material in museums but also for contemporary understandings of Scottish National identity. <br /
Ethos of Ambiguity: Artist Teachers and the Transparency Exclusion Paradox
Addressing changes in conditions for practitioners that can be related to education policy in England and Wales since 2010, this article presents issues faced by teachers of art and design and theorises responses in practice. The current insistence on transparency in education emerges through policy that audits performativity, in a limiting skills bank. Practitioners in Art and Design are particularly affected by what I term ‘the transparency-exclusion paradox’, as they battle to maintain the subject area and are ‘othered’ by the EBacc and Progress 8. I will discuss an emergent ‘ethos of ambiguity’ among artist-teachers and contemporary artists, with a theoretical basis informed by Beauvoir and Foucault. Empirical data from research participants will be evidenced, to explore strategies of response in inclusive social practice. This article adds to literature that considers the effects of policy in implementation and it contributes to research on creative expressions of ambiguity in the arts
Orbital anastomoses of the anterior deep temporal artery
The anterior deep temporal artery may provide a major collateral pathway to the intracranial circulation through anastomoses with branches of the ophthalmic artery. Review of carotid angiograms in 26 patients with internal carotid artery occlusive disease revealed anterior deep temporal to ophthalmic artery anastomoses in 16 cases. This route of collateral blood flow was associated in most instances with total occlusion of the cervical portion of the internal carotid artery. Three cases demonstrating the angiographic anatomy of the anterior deep temporal artery and its potential anastomoses with branches of the ophthalmic artery are presented. L'artère temporale profonde antérieure peut être à l'origine de circulation colatérale grâce à ses anastomoses avec l'artère ophtalmique. Une telle anastomose a été constatée 16 fois sur 26 cas de thrombose de l'artère carotide interne. Über die A. temporalis anterior ist über Anastomosen zu den Ästen der A. ophthalmica ein Kollateral-Kreislauf zu den intracraniellen Gefäßabschnitten möglich. Bei 26 Patienten mit einem A. carotis interna-Verschluß zeigte sich dieser Kreislauf in 16 Fällen. Es wird über 3 Fälle ausführlich berichtet, bei denen die angiographische Anatomie der A. temporalis anterior und die möglichen Anastomosen mit Ästen der A. ophthalmica besprochen wird.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46672/1/234_2004_Article_BF00335020.pd
A systematic autopsy survey of human infant bridging veins
In the first years of life, subdural haemorrhage (SDH) within the cranial cavity can occur through accidental and non-accidental mechanisms as well as from birth-related injury. This type of bleeding is the most common finding in victims of abusive head trauma (AHT). Historically, the most frequent cause of SDHs in infancy is suggested to be traumatic damage to bridging veins traversing from the brain to the dural membrane. However, several alternative hypotheses have been suggested for the cause and origin of subdural bleeding. It has also been suggested by some that bridging veins are too large to rupture through the forces associated with AHT. To date, there have been no systematic anatomical studies on infant bridging veins. During 43 neonatal, infant and young child post-mortem examinations, we have mapped the locations and numbers of bridging veins onto a 3D model of the surface of a representative infant brain. We have also recorded the in situ diameter of 79 bridging veins from two neonatal, one infant and two young children at post-mortem examination. Large numbers of veins, both distant from and directly entering the dural venous sinuses, were discovered travelling between the brain and dural membrane, with the mean number of veins per brain being 54.1 and the largest number recorded as 94. The mean diameter of the bridging veins was 0.93 mm, with measurements ranging from 0.05 to 3.07 mm. These data demonstrate that some veins are extremely small and subjectively, and they appear to be delicate. Characterisation of infant bridging veins will contribute to the current understanding of potential vascular sources of subdural bleeding and could also be used to further develop computational models of infant head injury
Some technique-dependent patterns of collateral flow during cerebral angiography
During selective transfemoral catheter cerebral angiography, anastomoses between external carotid branches and the vertebral artery, between the vertebral and deep or ascending cervical arteries, and between the middle meningeal and ophthalmic arteries can be demonstrated fairly frequently in patients with no known vascular abnormalities. One can occasionally show bidirectional filling of these anastomoses depending on the vessel injected. Visualization of these anastomoses occurs to a variable degree and is sometimes entirely technique-dependent, reflecting a transient increase in the intraluminal pressure during the injection of contrast medium.-Thus, demonstration of extracranial collateral arterial flow during cerebral angiography should not necessarily be interpreted as an abnormal phenomenon, such as may be seen with arterial occlusive disease, vascular malformation, or a very vascular tumor. Au cours de l'angiographie cérébrale parcathétérismes sélectifs par voie fémorale, peuvent apparaître des anastomoses entre des branches carotidiennes externes et l'artère vertébrale, entre l'artère vertébrale et les artères cérébrales profondes ou ascendantes et entre l'artère méningée moyenne et l'artère ophtalmique. Occasionnellement, on peut mettre en évidence un remplissage bidirectionnel de ces anastomoses, en rapport avec le vaisseau injecté. La visualisation de ces anastomoses se produit de facon variable dépend parfois entièrement de la technique, reflétant une augmentation transitoire de la pression dans l'artère durant l'injection du produit de contraste. Par conséquent, l'observation d'une circulation artérielle collatérale extracrânienne pendant une angiographie cérébrale ne représente pas nécéssairement un phénomène anormal tel qu'on le rencontre dans les troubles artériels occlusifs, dans les malformations vasculaires et dans les tumeurs vascularisées. Während der selektiven transfemoralen Katheter-Angiographie können sich Anastomosen zwischen Externa-Gefäßen und der A. vertebralis, zwischen der A. vertebralis und tiefen oder aufsteigenden cervicalen Arterien und zwischen der A. meningica media und der A. ophthalmica darstellen. Diese Befunde finden sich auch bei Patienten, bei denen keine Gef:aßanomalien vorliegen. Gelegentlich wird ein bidirektionaler Kontrastmitteldurchfluß durch diese Anastomosen nachgewiesen, dabei ist die Kontrastmittelfüllung von der Lokalisation der Kontrastmittelinjektion abhängig. Es zeigt sich also, daß diese unterschiedlichen Durchströmungen technisch bedingt werden können und nicht immer als abnormales Phänomen gedeutet werden können.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46671/1/234_2004_Article_BF00341594.pd
Global assessment of marine plastic exposure risk for oceanic birds
Plastic pollution is distributed patchily around the world’s oceans. Likewise, marine organisms that are vulnerable to plastic ingestion or entanglement have uneven distributions. Understanding where wildlife encounters plastic is crucial for targeting research and mitigation. Oceanic seabirds, particularly petrels, frequently ingest plastic, are highly threatened, and cover vast distances during foraging and migration. However, the spatial overlap between petrels and plastics is poorly understood. Here we combine marine plastic density estimates with individual movement data for 7137 birds of 77 petrel species to estimate relative exposure risk. We identify high exposure risk areas in the Mediterranean and Black seas, and the northeast Pacific, northwest Pacific, South Atlantic and southwest Indian oceans. Plastic exposure risk varies greatly among species and populations, and between breeding and non-breeding seasons. Exposure risk is disproportionately high for Threatened species. Outside the Mediterranean and Black seas, exposure risk is highest in the high seas and Exclusive Economic Zones (EEZs) of the USA, Japan, and the UK. Birds generally had higher plastic exposure risk outside the EEZ of the country where they breed. We identify conservation and research priorities, and highlight that international collaboration is key to addressing the impacts of marine plastic on wide-ranging species
Effects of body size, sex, parental care and moult strategies on auk diving behaviour outside the breeding season
Information on seabird foraging behaviour outside the breeding season is currently limited. This knowledge gap is critical as this period is energetically demanding due to post‐fledging parental care, feather moult and changing environmental conditions. Based on species’ body size, post‐fledging parental strategy and primary moult schedule we tested predictions for key aspects of foraging behaviour (Maximum Dive Depth (MDD), Daily Time Submerged (DTS) and Diurnal Dive Activity (DDA)) using dive depth data collected from three seabird species (common guillemot Uria aalge, razorbill Alca torda and Atlantic puffin Fratercula arctica) from the end of the breeding season (July) to mid‐winter (January). We found partial support for predictions associated with body size; guillemots had greater MDD than razorbills but MDD did not differ between razorbills and puffins, despite the former being 35% heavier. In accordance with sexual monomorphism in all three species, MDD did not differ overall between the sexes. However, in guillemots and razorbills there were sex‐specific differences, such that male guillemots made deeper dives than females, and males of both species had higher DTS. In contrast, there were no marked sex differences in dive behaviour of puffins in July and August in accordance with their lack of post‐fledging parental care and variable moult schedule. We found support for the prediction that diving effort would be greater in mid‐winter compared to the period after the breeding season. Despite reduced daylight in mid‐winter, this increase in DTS occurred predominantly during the day and only guillemots appeared to dive nocturnally to any great extent. In comparison to diving behaviour of these species recorded during the breeding season, MDD was shallower and DTS was greater during the non‐breeding period. Such differences in diving behaviour during the post‐breeding period are relevant when identifying potential energetic bottlenecks, known to be key drivers of seabird population dynamics
Global assessment of marine plastic exposure risk for oceanic birds
Plastic pollution is distributed patchily around the world’s oceans. Likewise, marine organisms that are vulnerable to plastic ingestion or entanglement have uneven distributions. Understanding where wildlife encounters plastic is crucial for targeting research and mitigation. Oceanic seabirds, particularly petrels, frequently ingest plastic, are highly threatened, and cover vast distances during foraging and migration. However, the spatial overlap between petrels and plastics is poorly understood. Here we combine marine plastic density estimates with individual movement data for 7137 birds of 77 petrel species to estimate relative exposure risk. We identify high exposure risk areas in the Mediterranean and Black seas, and the northeast Pacific, northwest Pacific, South Atlantic and southwest Indian oceans. Plastic exposure risk varies greatly among species and populations, and between breeding and non-breeding seasons. Exposure risk is disproportionately high for Threatened species. Outside the Mediterranean and Black seas, exposure risk is highest in the high seas and Exclusive Economic Zones (EEZs) of the USA, Japan, and the UK. Birds generally had higher plastic exposure risk outside the EEZ of the country where they breed. We identify conservation and research priorities, and highlight that international collaboration is key to addressing the impacts of marine plastic on wide-ranging species
Global assessment of marine plastic exposure risk for oceanic birds
Plastic pollution is distributed patchily around the world's oceans. Likewise, marine organisms that are vulnerable to plastic ingestion or entanglement have uneven distributions. Understanding where wildlife encounters plastic is crucial for targeting research and mitigation. Oceanic seabirds, particularly petrels, frequently ingest plastic, are highly threatened, and cover vast distances during foraging and migration. However, the spatial overlap between petrels and plastics is poorly understood. Here we combine marine plastic density estimates with individual movement data for 7137 birds of 77 petrel species to estimate relative exposure risk. We identify high exposure risk areas in the Mediterranean and Black seas, and the northeast Pacific, northwest Pacific, South Atlantic and southwest Indian oceans. Plastic exposure risk varies greatly among species and populations, and between breeding and non-breeding seasons. Exposure risk is disproportionately high for Threatened species. Outside the Mediterranean and Black seas, exposure risk is highest in the high seas and Exclusive Economic Zones (EEZs) of the USA, Japan, and the UK. Birds generally had higher plastic exposure risk outside the EEZ of the country where they breed. We identify conservation and research priorities, and highlight that international collaboration is key to addressing the impacts of marine plastic on wide-ranging species.B.L.C., C.H., and A.M. were funded by the Cambridge Conservation Initiative’s Collaborative Fund sponsored by the Prince Albert II of Monaco Foundation. E.J.P. was supported by the Natural Environment Research Council C-CLEAR doctoral training programme (Grant no. NE/S007164/1). We are grateful to all those who assisted with the collection and curation of tracking data. Further details are provided in the Supplementary Acknowledgements. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.Peer reviewe
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