Maintaining the relevance of international journalism – BBC’s Peter Horrocks POLIS Perugia Speech

This is the text of the speech given by Peter Horrocks, the BBC’s Director of Global News, as the POLIS keynote speech at the International Journalism Festival in Perugia on April 14th. It was chaired by POLIS director Charlie Beckett

Contraction and Retraction of Muscular Fibres, With Special Reference to the Uterus.

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The precambrian geology of an area between Messina and Tshipise Limpopo mobile belt

A Dissertation Submitted tc the Faculty of Science, University of the Witwatersrand, Johannesburg, for the degree of Doctor of Philosophy. Johannesburg 1981An area of about 200 'sq km has been mapped at a scale of 1 : 25 000 between Messina and Tshipise. Subsequent laboratory work has included petrographic, whole-rock and mineral analysis in order to describe the Precambrian rock-types and lithologies, their structure, and their metomorphic history. The Precambrian lithologies underlying the study area consist of grey banded basement gneisses of granodioritic composition, together with a large variety of supracrustal rocktypes. These include quartzo-feldspathic gneiss, Singeleletype granitoid gneiss, garnet-cordierite-sillimunite gneiss, sapphirine-bearing rock, garnet-orthopyroxene-plagioclase symplectite, pyroxenitic amphibolite, quartzite, banded magnetite quartzite, amphibolite, calc-silicate gneiss and marble. These supracrustal rocks may belong to a geosynclinal-type series of depv .» Led or extruded lithologies. Intrusive rocks of the Messina Layered Intrusion consist of gabbroic and anorthositic gneiss. Metapyroxenites and serpentinites also occur. Both ancient deformed and you ger fabric-free mafic dykes transect this stratigraphy. Polyphase deformation has produced complex and intense folding of the area. Early isoclinal and ductile folds, now manifest as tight intrafolial folds, have been refolded around later structures. Most fold hinges plunge moderately to the south-west. Considerable flattening, attenuation and alongstrike boudinaging of the units occurs in the region, probably as a result of regional simple shear The assymetry of the folds in the region suggest that this simple shear was left lateral. Peorce-type variation diagrams for data from the Messina Layered Intrusion show plagioclase fractionation trends, and support the argument that these rocks are of plutonic igneous origin. The anorthcsites were the earliest cumulates, with the gabbros forming by subsequent fractionation. Rayleigh's law indicates that about 70 per cent fractionation has occurred in these rocks. The parental liquid appears to have been anomalously enriched in rubidium. The supracrustal units have experienced a high-grade metamorphism between about 3 100 m.y. ago and 2 400 m.y. ago. The P-T conditions for this metamorphism range from about 9 kbar and 900 C at the 'peak' of the metamorphism, to about 4 kbar and 650°C, and thus represents a retrogression within the field of medium pressure granulites. Earlier high-pressure granulite metamorphism is indicated by assemblages reported from other regions in t.ie Central Zone of the Limpopo Mobile Belt. These data suggest that the supracrustal rocks were subjected to burial into regions of the lower crust up to 40 km depth, and geothermal gradients between 15°C/km and 35°C/km were experienced. Water activities were low durin.j this high-grade metoeorphism, with water making up not more than 10 per cent of the fluid present during this event. The onset of relative tectonic stability and the end of high-grade metamorphism was achieved by about 2 200 m.y. 0go

Proliferation of metallic domains caused by inhomogeneous heating near the electrically-driven transition in VO2_2 nanobeams

We discuss the mechanisms behind the electrically driven insulator-metal transition in single crystalline VO$_2$ nanobeams. Our DC and AC transport measurements and the versatile harmonic analysis method employed show that non-uniform Joule heating causes phase inhomogeneities to develop within the nanobeam and is responsible for driving the transition in VO$_{2}$. A Poole-Frenkel like purely electric field induced transition is found to be absent and the role of percolation near and away from the electrically driven transition in VO$_{2}$ is also identified. The results and the harmonic analysis can be generalized to many strongly correlated materials that exhibit electrically driven transitions

Ages on weathered Plio-Pleistocene tephra sequences, western North Island, New Zealand

Using the zircon fission-track method, we have obtained five ages on members of two strongly-weathered silicic, Pliocene-Pleistocene tephra sequences, the Kauroa and Hamilton Ash formations, in western North Island, New Zealand. These are the first numerical ages to be obtained directly on these deposits. Of the Kauroa Ash sequence, member K1 (basal unit) was dated at 2.24 ± 0.29 Ma, confirming a previous age of c. 2.25 Ma obtained (via tephrochronology)from K/Ar ages on associated basalt lava. Members K2 and K3 gave indistinguishable ages between 1.68 ± 0.12 and 1.43 ± 0.17 Ma. Member K12, a correlative of Oparau Tephra and probably also Ongatiti Ignimbrite, was dated at 1.28 ± 0.11 Ma, consistent with an age of 1.23 ± 0.02 Ma obtained by various methods on Ongatiti Ignimbrite. Palaeomagnetic measurements indicated that members K13 to K15 (top unit, Waiterimu Ash) are aged between c. 1.2 Ma and 0.78 Ma. Possible sources of the Kauroa Ash Formation include younger volcanic centres in the southern Coromandel Volcanic Zone or older volcanic centres in the Taupo Volcanic Zone, or both. Of the Hamilton Ash sequence, the basal member Ohinewai Ash (HI) was dated at 0.38 ± 0.04 Ma. This age matches those obtained by various methods on Rangitawa Tephra of 0.34-0.35 Ma, supporting correlation with this Whakamaru-caldera derived deposit. The origin of the other Hamilton Ash beds is unknown but various younger volcanic centres in the Taupo Volcanic Zone are possible sources. The topmost member, Tikotiko Ash (H6-H7), is estimated to be aged between c. 0.18 and 0.08 Ma. Various silicic pyroclastic deposits documented in North Island and in marine cores may be co-eval with members of the Kauroa Ash and Hamilton Ash sequences on the basis of their age

Unification in the Description Logic EL

The Description Logic EL has recently drawn considerable attention since, on the one hand, important inference problems such as the subsumption problem are polynomial. On the other hand, EL is used to define large biomedical ontologies. Unification in Description Logics has been proposed as a novel inference service that can, for example, be used to detect redundancies in ontologies. The main result of this paper is that unification in EL is decidable. More precisely, EL-unification is NP-complete, and thus has the same complexity as EL-matching. We also show that, w.r.t. the unification type, EL is less well-behaved: it is of type zero, which in particular implies that there are unification problems that have no finite complete set of unifiers.Comment: 31page

Paramedic disaster health management competencies: a scoping review

Study/Objective: This scoping review aims to identify, categorise and explore the existing range of paramedic disaster health management competencies that have been developed internationally. The objective of the study is to assist EMS agencies to develop core competencies specific to their own environments in order to standardise teaching in the area of paramedic disaster health management response. Background: Paramedics play an essential role in all phases of disaster health management. Previous research has identified potential gaps in content and challenges to the sustainability of knowledge acquired through occasional disaster response training by paramedics. For paramedics to respond competently, they must be equipped with the necessary skills to provide comprehensive care to the populations affected by disasters. Despite this the literature shows that education and training for disaster response is variable and that an evidence based study specifically designed to outline sets of core competencies for Australian paramedics has never been undertaken. Methods: A systematic scoping review will be conducted using the Joanna Briggs Institute (JBI) methodology. The review will use information from four databases: PubMed, MEDLINE, ScienceDirect, and Scopus. Keywords and inclusion and exclusion criteria will be identified as strategies to use in this review. Results: Results will be extracted, mapped, and categorised from appropriate studies. The identified core competencies will be sorted into common domains such as communication, operations, planning, logistics, incident command systems and ethics. A descriptive analysis of the results will then be undertaken. Conclusion: Further research is needed to develop core competencies specific to Australian paramedics in order to standardise teaching in the area of disaster health management response. This study will assist agencies from all jurisdictions in evaluating or creating disaster curricula that adequately prepares and maintains paramedics for an effective all hazards disaster response

Automated extraction of seed morphological traits from images

The description of biological objects, such as seeds, mainly relies on manual measurements of few characteristics, and on visual classification of structures, both of which can be subjective, error prone and time-consuming. Image analysis tools offer means to address these shortcomings, but we currently lack a method capable of automatically handling seeds from different taxa with varying morphological attributes and obtaining interpretable results. Here, we provide a simple image acquisition and processing protocol and introduce Traitor, an open-source software available as a command-line interface (CLI), which automates the extraction of seed morphological traits from images. The workflow for trait extraction consists of scanning seeds against a high-contrast background, correcting image colours, and analysing images with the software. Traitor is capable of processing hundreds of images of varied taxa simultaneously with just three commands, and without a need for training, manual fine-tuning or thresholding. The software automatically detects each object in the image and extracts size measurements, traditional morphometric descriptors widely used by scientists and practitioners, standardised shape coordinates, and colorimetric measurements. The method was tested on a dataset comprising of 91,667 images of seeds from 1228 taxa. Traitor's extracted average length and width values closely matched the average manual measurements obtained from the same collection (concordance correlation coefficient of 0.98). Further, we used a large image dataset to demonstrate how Traitor's output can be used to obtain representative seed colours for taxa, determine the phylogenetic signal of seed colour, and build objective classification categories for shape with high levels of visual interpretability. Our approach increases productivity and allows for large-scale analyses that would otherwise be unfeasible. Traitor enables the acquisition of data that are readily comparable across different taxa, opening new avenues to explore functional relevance of morphological traits and to advance on new tools for seed identification

GALA: an international multicentre randomised trial comparing general anaesthesia versus local anaesthesia for carotid surgery

Background: Patients who have severe narrowing at or near the origin of the internal carotid artery as a result of atherosclerosis have a high risk of ischaemic stroke ipsilateral to the arterial lesion. Previous trials have shown that carotid endarterectomy improves long-term outcomes, particularly when performed soon after a prior transient ischaemic attack or mild ischaemic stroke. However, complications may occur during or soon after surgery, the most serious of which is stroke, which can be fatal. It has been suggested that performing the operation under local anaesthesia, rather than general anaesthesia, may be safer. Therefore, a prospective, randomised trial of local versus general anaesthesia for carotid endarterectomy was proposed to determine whether type of anaesthesia influences peri-operative morbidity and mortality, quality of life and longer term outcome in terms of stroke-free survival. Methods/design: A two-arm, parallel group, multicentre randomised controlled trial with a recruitment target of 5000 patients. For entry into the study, in the opinion of the responsible clinician, the patient requiring an endarterectomy must be suitable for either local or general anaesthesia, and have no clear indication for either type. All patients with symptomatic or asymptomatic internal carotid stenosis for whom open surgery is advised are eligible. There is no upper age limit. Exclusion criteria are: no informed consent; definite preference for local or general anaesthetic by the clinician or patient; patient unlikely to be able to co-operate with awake testing during local anaesthesia; patient requiring simultaneous bilateral carotid endarterectomy; carotid endarterectomy combined with another operation such as coronary bypass surgery; and, the patient has been randomised into the trial previously. Patients are randomised to local or general anaesthesia by the central trial office. The primary outcome is the proportion of patients alive, stroke free ( including retinal infarction) and without myocardial infarction 30 days post-surgery. Secondary outcomes include the proportion of patients alive and stroke free at one year; health related quality of life at 30 days; surgical adverse events, re-operation and re-admission rates; the relative cost of the two methods of anaesthesia; length of stay and intensive and high dependency bed occupancy