27 research outputs found
Metamorphism of the Sierra de Maz and implications for the tectonic evolution of the MARA terrane
The Mesoproterozoic MARA terrane of western South America is a composite igneous-metamorphic complex that is important for Paleozoic paleogeographic reconstructions and the relative positions of Laurentia and Gondwana. The magmatic and detrital records of the MARA terrane are consistent with a Laurentian origin; however, the metamorphic and deformation records lack sufficient detail to constrain the correlation of units within the MARA terrane and the timing and mechanisms of accretion to the Gondwana margin.
Combined regional mapping, metamorphic petrology, and garnet and monazite geochronology from the Sierra de Maz of northwest Argentina suggest that the region preserves four distinct litho-tectonic units of varying age and metamorphic conditions that are separated by middle- to lower-crustal ductile shear zones. The Zaino and Maz Complexes preserve Barrovian metamorphism and ages that are distinct from other units within the region. The Zaino and Maz Complexes both record metamorphism ca. 430–410 Ma and show no evidence of the regional Famatinian orogeny (ca. 490–455 Ma). In addition, the Maz Complex records an earlier granulite facies event at ca. 1.2 Ga. The Taco and Ramaditas Complexes, in contrast, experienced medium- and low-pressure upper amphibolite to granulite facies metamorphism, respectively, between ca. 470–460 Ma and were later deformed at ca. 440–420 Ma.
The Maz shear zone that bounds the Zaino and Maz Complexes records sinistral oblique to sinistral deformation between ca. 430–410 Ma. The data suggest that at least some units in the MARA terrane were accreted by translation, and the Gondwana margin of northwest Argentina transitioned from a dominantly convergent margin to a highly oblique margin in the Silurian
Genomic investigations of unexplained acute hepatitis in children
Since its first identification in Scotland, over 1,000 cases of unexplained paediatric hepatitis in children have been reported worldwide, including 278 cases in the UK1. Here we report an investigation of 38 cases, 66 age-matched immunocompetent controls and 21 immunocompromised comparator participants, using a combination of genomic, transcriptomic, proteomic and immunohistochemical methods. We detected high levels of adeno-associated virus 2 (AAV2) DNA in the liver, blood, plasma or stool from 27 of 28 cases. We found low levels of adenovirus (HAdV) and human herpesvirus 6B (HHV-6B) in 23 of 31 and 16 of 23, respectively, of the cases tested. By contrast, AAV2 was infrequently detected and at low titre in the blood or the liver from control children with HAdV, even when profoundly immunosuppressed. AAV2, HAdV and HHV-6 phylogeny excluded the emergence of novel strains in cases. Histological analyses of explanted livers showed enrichment for T cells and B lineage cells. Proteomic comparison of liver tissue from cases and healthy controls identified increased expression of HLA class 2, immunoglobulin variable regions and complement proteins. HAdV and AAV2 proteins were not detected in the livers. Instead, we identified AAV2 DNA complexes reflecting both HAdV-mediated and HHV-6B-mediated replication. We hypothesize that high levels of abnormal AAV2 replication products aided by HAdV and, in severe cases, HHV-6B may have triggered immune-mediated hepatic disease in genetically and immunologically predisposed children
The Influence of Noise Level on the Intelligibility of Artificial Larynx Speech Presented Auditorily and Audio-Visually
This study used a group of ten listeners with no previous exposure to artificial larynx speech to judge the intelligibility of Western Electric No. 5 speakers across varying noise conditions with audio versus audiovisual modes of presentation. Percentage scores across the conditions showed a decrease in intelligibility in the audio condition and a further decrease when noise was introduced. Percentage scores for the best condition (audiovisual plus a high signal to noise ratio) were low due to the listeners\u27 unfamiliarity with artificial larynx speech. Further analysis of listener responses indicated a proximity to the target response. Implications of these findings are discussed
Review of \u3ci\u3eNative Faces: Indian Cultures in American Art\u3c/i\u3e by Patricia Trenton and Patrick Houlihan
Native Faces is the catalogue to an exhibition of the same name presented at the Southwest Museum in Los Angeles in 1984 and at Omaha\u27s Joslyn Art Museum in 1985. The show featured late nineteenth and early twentieth century paintings of California, Southwest, and Plains Indian subjects by wellknown artists such as Joseph Sharp, Ernest Blumenschein and E. Irving Couse. The paintings were shown with related Indian artifacts and historic photographs. The catalogue focuses on sixteen of the paintings and their related material, with commentary on each by Patricia Trenton, an art historian, and Patrick Houlihan, an anthropologist
Text Message Intervention to Reduce Repeat Self-harm in Patients Presenting to the Emergency Department-A Study Protocol
Aims: To assess the feasibility of using supportive interactive text messages to reduce repeat self-harm, and to reduce the frequency and intensity of suicidal ideation and suicidal behaviour in patients discharged from an Emergency Department (ED) after an episode of self-harm. Study Design: Prospective rater blinded randomised trial. Place and Duration of Study: Sample: ED of Beaumont Hospital, Dublin, Ireland. Methodology: 100 patients presenting with self-harm to the ED will be randomised to receive treatment as usual plus supportive and interactive text messages for three months or to receive treatment as usual. Patients in both groups will be followed up at 1, 3 and 6 months to ascertain frequency and intensity of thoughts of self-harm and selfharming behaviour. Data will be analysed on an intention-to-treat basis using SPSS version 20 for Windows with descriptive statistics, student’s t-test, ANOVA analysis and chi-square tests. Results: We hypothesize that supportive, informative and interactive text messages delivered to patients discharged from an ED after an episode of self-harm will significantly reduce the frequency and intensity of thoughts of self-harm and self-harming behaviour in patients compared with those receiving only follow-up treatment as usual. A secondary hypothesis is that patients receiving the text messages will report an overall satisfaction with the text messaging system. Conclusion: This is a low cost, simple strategy which, if shown to have a significant impact on reducing rates of self-harming thoughts and behaviours in patients who have self-harmed, will allow progress in an area of great clinical importance. Further larger studies could then progress to clarify the potential impact on suicide rates
Predicted cardiac and second cancer risks for patients undergoing VMAT for mediastinal Hodgkin lymphoma
Background and purpose: To predict treatment-related cardiovascular disease (CVD) and second cancer 30-year absolute mortality risks (AMR30) for patients with mediastinal Hodgkin lymphoma in a large multicentre radiation oncology network in Ireland.
Material and methods: This study includes consecutive patients treated for mediastinal lymphoma using chemotherapy and involved site radiotherapy (RT) 2016–2019. Radiation doses to heart, left ventricle, cardiac valves, lungs, oesophagus, carotid arteries and female breasts were calculated. Individual CVD and second cancer AMR30 were predicted using Irish background population rates and dose–response relationships.
Results: Forty-four patients with Hodgkin lymphoma were identified, 23 females, median age 28 years. Ninety-eight percent received anthracycline, 80% received 4–6 cycles ABVD. Volumetric modulated arc therapy (VMAT) ± deep inspiration breath hold (DIBH) was delivered, median total prescribed dose 30 Gy. Average mean heart dose 9.8 Gy (range 0.2–23.8 Gy). Excess treatment-related mean AMR30 from CVD was 2.18% (0.79, 0.90, 0.01, 0.13 and 0.35% for coronary disease, heart failure, valvular disease, stroke and other cardiac diseases), 1.07% due to chemotherapy and a further 1.11% from RT. Excess mean AMR30 for second cancers following RT were: lung cancer 2.20%, breast cancer in females 0.34%, and oesophageal cancer 0.28%.
Conclusion: For patients with mediastinal lymphoma excess mortality risks from CVD and second cancers remain clinically significant despite contemporary chemotherapy and photon-RT. Efforts to reduce the toxicity of combined modality treatment, for example, using DIBH, reduced margins and advanced RT, e.g. proton beam therapy, should be continued to further reduce potentially fatal treatment effects