29 research outputs found

    Cerebral aneurysm exclusion by CT angiography based on subarachnoid hemorrhage pattern: a retrospective study

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    <p>Abstract</p> <p>Background</p> <p>To identify patients with spontaneous subarachnoid hemorrhage for whom CT angiography alone can exclude ruptured aneurysms.</p> <p>Methods</p> <p>An observational retrospective review was carried out of all consecutive patients with non-traumatic subarachnoid hemorrhage who underwent both CT angiography and catheter angiography to exclude an aneurysm. CT angiography negative cases (no aneurysm) were classified according to their CT hemorrhage pattern as "aneurismal", "perimesencephalic" or as "no-hemorrhage."</p> <p>Results</p> <p>Two hundred and forty-one patients were included. A CT angiography aneurysm detection sensitivity and specificity of 96.4% and 96.0% were observed. All 35 cases of perimesencephalic or no-hemorrhage out of 78 CT angiography negatives also had negative angiography findings.</p> <p>Conclusions</p> <p>CT angiography is self-reliant to exclude ruptured aneurysms when either a perimesencephalic hemorrhage or no-hemorrhage pattern is identified on the CT within a week of symptom onset.</p

    Variation within and between Frankliniella Thrips Species in Host Plant Utilization

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    Anthophilous flower thrips in the genus Frankliniella (Thysanoptera: Thripidae) exploit ephemeral plant resources and therefore must be capable of successfully locating appropriate hosts on a repeated basis, yet little is known of interspecific and intraspecific variation in responses to host plant type and nutritional quality. Field trials were conducted over two seasons to determine if the abundance of males and females of three common Frankliniella species, F. occidentalis (Pergande), F. tritici (Fitch) and F. bispinosa (Morgan), their larvae, and a key predator, Orius insidiosus (Say) (Hemiptera: Anthocoridae) were affected by host plant type and plant nutritional quality. Two host plants, pepper, Capsicum annuum L. (Solanales: Solanaceae) and tomato, Solanum lycopersicum L. that vary in suitability for these species were examined, and their nutritional quality was manipulated by applying three levels of nitrogen fertilization (101 kg/ha, 202 kg/ha, 404 kg/ha). F. occidentalis females were more abundant in pepper than in tomato, but males did not show a differential response. Both sexes of F. tritici and F. bispinosa were more abundant in tomato than in pepper. Larval thrips were more abundant in pepper than in tomato. Likewise, O. insidiosus females and nymphs were more abundant in pepper than in tomato. Only F. occidentalis females showed a distinct response to nitrogen fertilization, with abundance increasing with fertilization. These results show that host plant utilization patterns vary among Frankliniella spp. and should not be generalized from results of the intensively studied F. occidentalis. Given the different pest status of these species and their differential abundance in pepper and tomato, it is critical that scouting programs include species identifications for proper management

    Predictions for the Leptonic Dirac CP Violation Phase: a Systematic Phenomenological Analysis

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    We derive predictions for the Dirac phase ÎŽ\delta present in the 3×33\times 3 unitary neutrino mixing matrix U=Ue† UÎœU = U_e^{\dagger} \, U_{\nu}, where UeU_e and UÎœU_{\nu} are 3×33\times 3 unitary matrices which arise from the diagonalisation respectively of the charged lepton and the neutrino mass matrices. We consider forms of UeU_e and UÎœU_{\nu} allowing us to express ÎŽ\delta as a function of three neutrino mixing angles, present in UU, and the angles contained in UÎœU_{\nu}. We consider several forms of UÎœU_{\nu} determined by, or associated with, symmetries, tri-bimaximal, bimaximal, etc., for which the angles in UÎœU_{\nu} are fixed. For each of these forms and forms of UeU_e allowing to reproduce the measured values of the neutrino mixing angles, we construct the likelihood function for cos⁥Ύ\cos \delta, using i) the latest results of the global fit analysis of neutrino oscillation data, and ii) the prospective sensitivities on the neutrino mixing angles. Our results, in particular, confirm the conclusion reached in earlier similar studies that the measurement of the Dirac phase in the neutrino mixing matrix, together with an improvement of the precision on the mixing angles, can provide unique information about the possible existence of symmetry in the lepton sector
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