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BackgroundThere is a paucity of data on anesthesia-related outcomes for endovascular treatment (EVT) in the extended window (>6 hours from ischemic stroke onset). We compared functional and safety outcomes between local anesthesia (LA) without sedation, conscious sedation (CS) and general anesthesia (GA).MethodsPatients who underwent EVT in the early (<6 hours) and extended time windows using LA, CS, or GA between October 2015 and March 2020 were included from a UK national stroke registry. Multivariable analyses were performed, adjusted for age, sex, baseline stroke severity, pre-stroke disability, EVT technique, center, procedural time and IV thrombolysis.ResultsA total of 4337 patients were included, 3193 in the early window (1135 LA, 446 CS, 1612 GA) and 1144 in the extended window (357 LA, 134 CS, 653 GA). Compared with GA, patients treated under LA alone had increased odds of an improved modified Rankin Scale (mRS) score at discharge (early: adjusted common (ac) OR=1.50, 95% CI 1.29 to 1.74, p=0.001; extended: acOR=1.29, 95% CI 1.01 to 1.66, p=0.043). Similar mRS scores at discharge were found in the LA and CS cohorts in the early and extended windows (p=0.21). Compared with CS, use of GA was associated with a worse mRS score at discharge in the early window (acOR=0.73, 95% CI 0.45 to 0.96, p=0.017) but not in the extended window (p=0.55). There were no significant differences in the rates of symptomatic intracranial hemorrhage or in-hospital mortality across the anesthesia modalities in the extended window.ConclusionLA without sedation during EVT was associated with improved functional outcomes compared with GA, but not CS, within and beyond 6 hours from stroke onset. Prospective studies assessing anesthesia-related outcomes in the extended time window are warranted.

New results for the process of discrete-cell, reverse mode gravure coating are presented, with the model considering a single cell and taking account of web thickness (stiffness) – an important feature neglected in previous analyses. Key results are: (i) confirmation that web tension, over the range encountered industrially, has negligible influence on web deformation; (ii) that web tension plays a secondary role to that of web stiffness. For parameters characteristic of those encountered in a typical coating operation the level of web deformation is found to be small, alluding to the importance of the two different length scales in the overall process – that at the cell (small) and coating bead (large) level.

High-fidelity aeroelastic simulations of the response of flexible wings to a sudden gust can result in a huge computing effort, making the search for the best wing design prohibitively expensive. As an alternative, a cost-effective multifidelity metamodelling-based optimization strategy, where a metamodel of a high-fidelity aeroelastic simulation response is built by tuning a lower fidelity aeroelastic simulation response, is proposed. In order to address and validate such an approach, both linear and non-linear aeroelastic equations for an aerofoil employing different levels of complexity for expressing the aerodynamic load are used for the high- and low-fidelity models. An aeroelastic gust response evaluation problem is formulated for the flexible wing of a small unmanned air vehicle, whose characteristic size makes it particularly susceptible to gusts. Three different approaches to tune the low-fidelity model, both explicit and implicit, are investigated and compared. Good agreement between the high-fidelity model and the corrected low-fidelity one shows that the proposed approach is indeed suitable for optimization of the aeroelastic gust performance of flexible wings.

Abstract: New results for the process of discrete-cell, reverse mode gravure coating are presented, with the model considering a single cell and taking account of web thickness (stiffness) – an important feature neglected in previous analyses. Key results are: (i) confirmation that web tension, over the range encountered industrially, has negligible influence on web deformation; (ii) that web tension plays a secondary role to that of web stiffness. For parameters characteristic of those encountered in a typical coating operation the level of web deformation is found to be small, alluding to the importance of the two different length scales in the overall process – that at the cell (small) and coating bead (large) level.

This article addresses the question of how science learning can be improved. It recognizes that, while learners themselves are responsible for their own learning, the quality of this learning is greatly influenced when appropriate resources are available to learners. These resources are provided through a partnership between teachers and learners. Three different types of resource are discussed. Tools, in the form of computer tools and conceptual tools, make tasks easier and allow learners to undertake tasks they would not otherwise be able to do. Tasks can facilitate effective learning by creating effective spaces for learners to work in, embodying key aspects of the disciplines of science, providing effective and authentic opportunities for learners to learn, and facilitating a dialogue between learners’ ideas and their experiences of the natural world. Environment – the ecology in which learning happens – provides three sources of information through the human, social, and conceptual worlds. When key aspects of these worlds are manifested in the environment, they scaffold the learning of science content, the nature of science, and the learning process itself, all of which are required for the deep understanding of science that constitutes improved science learning.

What are the implications of cognitive science for the design of instructional materials given its central concern with meaningful learning? This question was addressed during an attempt to improve the quality of learning in an introductory non-calculus college physics course where a major intellectual problem that many students face is the development of a coherent view of the information provided to them. The absence of a conceptual framework may contribute to the rapid loss of information often observed among many students shortly after their taking a test. Lack of a conceptual framework also may account for the frequent use of trial-and-error approaches to using formulae. This report cites the use of schema theory for the development of a generative schema or a set of schemas that could be used by students to integrate all of the physics content, and for the design of a means for representing and teaching the schema(s) in a set of instructional materials.

Conceptual conflict has long been recognized as a factor that could facilitate student learning. Due, however, to the lack of a convincing explanation of why it occurs, and how it can be resolved, it has seldom been used in instructional design. Its potential use in instruction is particularly relevant in the light of the recent, well-documented finding that students' existing conceptions frequently constitute a barrier to effective learning. This article examines conceptual conflict in the light of an epistemological model of learning as conceptual change. This analysis shows that the conceptual change model provides an explanation of conceptual conflict which is sufficiently detailed to allow it to be used in the design of instruction. The results of two studies, the first of which addressed the concepts of mass, volume, and density, and the second, the concept of speed, show that instruction, designed in this way, is effective in changing students' existing conceptions.

The techniques of transmission electron microscopy (TEM), including ultrastructural myeloperoxidase cytochemistry (MPO), and immunological marker analysis, have been used to classify 58 “difficult” cases of acute leukemia where a precise diagnosis could not be made on the basis of conventional light microscopy and cytochemistry. TEM with MPO proved most valuable in characterizing 15 cases of acute myeloid leukemia and its variants, as well as defining complex cellular subpopulations in 11 cases of chronic myeloid leukemia in blast crisis. Immunological marker studies provided conclusive evidence of lymphoid differentiation in 18 cases of acute lymphoblastic leukemia and related disorders. In addition, the combined techniques were used to document 14 cases of terminal transferase-positive acute myeloid leukemia. This study demonstrates that these 2 techniques provide overlapping and complementary information for accurate diagnosis and classification of morphologically difficult hematological malignancies.

Aerodynamic and meteorological concepts are combined in a procedure for estimating ground concentrations of effluents from stacks with various possible heights and exit gas velocities. The operation of each of the several influences at work is first described. A detailed example is then given of how the most important phases were integrated into a consistent procedure for predicting ground concentrations in answer to a specific design problem. Further improvements and refinements of the method are desirable and are being incorporated in a later study.

A 68‐year‐old man was first diagnosed as having acute myelomonoblastic leukaemia on March 17,1983. After two remissions with treatment, he suffered a further relapse, which caused him to present with a red eye, visual failure, and oedema of the right optic nerve head. Examination of cerebrospinal fluid that was obtained on lumbar puncture demonstrated an acute central nervous system relapse. Computed tomographic scanning led to the diagnosis of leukaemic infiltration of the optic nerve. Systemic and intrathecal treatment by appropriate chemotherapy and by orbital radiotherapy led to resolution of the clinical problem.