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Can the ischemic penumbra be identified on noncontrast CT of acute stroke?

<p><b>Background and Purpose:</b> Early ischemic changes on noncontrast CT in acute stroke include both hypoattenuation and brain swelling, which may have different pathophysiological significance.</p> <p><b>Methods:</b> Noncontrast CT and CT perfusion brain scans from patients with suspected acute stroke <6 hours after onset were reviewed. Five raters independently scored noncontrast CTs blind to clinical data using the Alberta Stroke Program Early CT Score (ASPECTS). Each ASPECTS region was scored as hypodense or swollen. A separate reviewer measured time to peak and cerebral blood volume in each ASPECTS region on CT perfusion. Time to peak and cerebral blood volume were compared for each region categorized as normal, hypodense, or isodense and swollen.</p> <p><b>Results:</b> Scans of 32 subjects a median 155 minutes after onset yielded 228 regions with both CT perfusion and noncontrast CT data. Isodense swelling was associated with significantly higher cerebral blood volume (P=0.016) and with penumbral perfusion (posttest:pretest likelihood ratio 1.44 [95% CI: 0.68 to 2.90]), whereas hypodensity was associated with more severe time to peak delay and with core perfusion (likelihood ratio 3.47 [95% CI: 1.87 to 6.34]). Neither isodense swelling nor hypodensity was sensitive for prediction of perfusion pattern, but appearances were highly specific (87.2% and 91.0% for penumbra and core, respectively). Intrarater agreement was good or excellent, but interrater agreement for both hypodensity and swelling was poor.</p> <p><b>Conclusions:</b> Regions exhibiting hypoattenuation are likely to represent the infarct core, whereas regions that are isodense and swollen have increased cerebral blood volume and are more likely to signify penumbral perfusion. Although noncontrast CT is not sensitive for detection of core and penumbra, appearances are specific. Some information on tissue viability can therefore be obtained from noncontrast CT.</p&gt

From the 'cinematic' to the 'anime-ic': Issues of movement in anime

This is the author's accepted manuscript. The final published article is available from the link below.This article explores the way that movement is formally depicted in anime. Drawing on Thomas Lamarre's concepts of the `cinematic' and the `anime-ic', the article interrogates further the differences in movement and action in anime from traditional filmic form. While often considered in terms of `flatness', anime offers spectacle, character development and, ironically, depth through the very form of movement put to use in such texts.The article questions whether the modes of address at work in anime are unique to this form of animation.Taking into account how the terms `cinematic' and `anime-ic' can be understood (and by extension the cinematic and animatic apparatus), the article also begins to explore how viewers might identify with such images

A systematic review of the current evidence regarding interventions for anxiety, PTSD, sleepiness and fatigue in the law enforcement workplace

© 2019 National Institute of Occupational Safety and Health. Law enforcement is inherently stressful, and police officers are particularly vulnerable to mental and physical disorders. As such, researchers are currently assessing intervention strategies that may combat or manage these psychological, physical and mental issues. To review most recent information regarding anxiety, PTSD, and sleepiness and fatigue and identify the interventions and treatments proposed to overcome work related stressors and associated mental illnesses inflicting law enforcement officers. The EMBASE, OVID MEDLINE and PsycINFO databases were canvassed for articles investigating anxiety, post-traumatic stress disorder, sleepiness, and fatigue. Initial article selections were made based on title, whilst final inclusion was informed by a full critical appraisal with respect to the primary and secondary effects. The systematic search returned 363 records, of which 183 were unique. Following screening, 43 records were included in the final review. The included literature assessed the efficacy of several interventions, and provided a number of recommendations regarding interventions, and policy. Moreover, literature indicates that police officers benefit from interventions targeting work-related stress and potential psychological disorders, if these interventions are continuous. Furthermore, larger controlled studies are required to further elucidate the benefits of psychosocial intervention in law enforcement

Mimicking protein environments with bioinorganic models

Through the design and application of a novel modular synthetic strategy, a diverse family of phosphate receptors has been synthesised. The receptors were based around a complexed metal centre such as zinc (II) or copper (II) within a polyazamacrocycle framework. The initial design was to couple the polyazamacrocycle directly to a crown ether system to give a heteroditopic scaffold where the two components were in close proximity to each other. Due to the synthetic difficulties encountered, a novel approach was developed, whereby the use of an amino acid linker was employed to couple the two species. The modular approach successfully allowed the variation of the metal centre through incorporation of different sized polyazamacrocycles. In the first instance we used a four-nitrogen donor host, cylen, to chelate zinc and in the second we attached a smaller triazamacrocycle, tacn to complex copper metal. The linker was changed to allow variations in polarity, functionality and structure through the selection of specific backbone residues. The synthesis and characterisation of glycine, aminodiacetic acid and glutamic acid derivatives proved that the methodology was effective and viable for a number of different linkers with varying structure. The use of iminodiacetic acid enabled the coupling of two cyclen metal hosts which enabled the synthesis of a bimetallic zinc complex and a novel tritopic system. Most importantly, the artificial receptors that we have created were shown to be excellent hosts for phosphate moieties. The proposed mode of binding in our systems was entropically driven through the efficient desolvation of the crown ether cavity upon phosphate binding. The interactions were in general, endothermic (+DH°) which was assigned to the reorganisation of solvent molecules upon expulsion which is in agreement with a growing body of evidence in the literature. Through isothermal titration calorimetry, 1H NMR and UV/vis titration experiments, we were able to determine that the ditopic systems acted as ion pair receptors. The binding of one ion affected the affinity of the ion partner. In the case of ZnL1.(OTf)2 it was shown that the individual binding of the cation is negligible but in the presence of phosphate the cation exerts a positive influence on the binding of the anion. We were able to calculate through simple control experiments that the binding of inorganic phosphate with a number of different metal counter ions exhibited positive cooperativity. This is one of the first examples of positive cooperativity between ion pairs in an aqueous environment at physiological pH

The Digital Flynn Effect: Complexity of Posts on Social Media Increases over Time

Parents and teachers often express concern about the extensive use of social media by youngsters. Some of them see emoticons, undecipherable initialisms and loose grammar typical for social media as evidence of language degradation. In this paper, we use a simple measure of text complexity to investigate how the complexity of public posts on a popular social networking site changes over time. We analyze a unique dataset that contains texts posted by 942, 336 users from a large European city across nine years. We show that the chosen complexity measure is correlated with the academic performance of users: users from high-performing schools produce more complex texts than users from low-performing schools. We also find that complexity of posts increases with age. Finally, we demonstrate that overall language complexity of posts on the social networking site is constantly increasing. We call this phenomenon the digital Flynn effect. Our results may suggest that the worries about language degradation are not warranted

Ferromagnetism in defect-ridden oxides and related materials

The existence of high-temperature ferromagnetism in thin films and nanoparticles of oxides containing small quantities of magnetic dopants remains controversial. Some regard these materials as dilute magnetic semiconductors, while others think they are ferromagnetic only because the magnetic dopants form secondary ferromagnetic impurity phases such as cobalt metal or magnetite. There are also reports in d0 systems and other defective oxides that contain no magnetic ions. Here, we investigate TiO2 (rutile) containing 1 - 5% of iron cations and find that the room-temperature ferromagnetism of films prepared by pulsed-laser deposition is not due to magnetic ordering of the iron. The films are neither dilute magnetic semiconductors nor hosts to an iron-based ferromagnetic impurity phase. A new model is developed for defect-related ferromagnetism which involves a spin-split defect band populated by charge transfer from a proximate charge reservoir in the present case a mixture Fe2+ and Fe3+ ions in the oxide lattice. The phase diagram for the model shows how inhomogeneous Stoner ferromagnetism depends on the total number of electrons Ntot, the Stoner exchange integral I and the defect bandwidth W; the band occupancy is governed by the d-d Coulomb interaction U. There are regions of ferromagnetic metal, half-metal and insulator as well as nonmagnetic metal and insulator. A characteristic feature of the high-temperature Stoner magnetism is an an anhysteretic magnetization curve which is practically temperature independent below room temperature. This is related to a wandering ferromagnetic axis which is determined by local dipole fields. The magnetization is limited by the defect concentration, not by the 3d doping. Only 1-2 % of the volume of the films is magnetically ordered.Comment: 22 pages, 6 figure

Determinantal Characterization of Canonical Curves and Combinatorial Theta Identities

We characterize genus g canonical curves by the vanishing of combinatorial products of g+1 determinants of Brill-Noether matrices. This also implies the characterization of canonical curves in terms of (g-2)(g-3)/2 theta identities. A remarkable mechanism, based on a basis of H^0(K_C) expressed in terms of Szego kernels, reduces such identities to a simple rank condition for matrices whose entries are logarithmic derivatives of theta functions. Such a basis, together with the Fay trisecant identity, also leads to the solution of the question of expressing the determinant of Brill-Noether matrices in terms of theta functions, without using the problematic Klein-Fay section sigma.Comment: 35 pages. New results, presentation improved, clarifications added. Accepted for publication in Math. An

Defining plant resistance against Phytophthora Cinnamomi and application of resistance to revegetation

Phytophthora cinnamomi is a soil borne plant pathogen that causes devastating disease in many Australian ecosystems and threatens the survival of native flora. Compared with the number of plant species that are susceptible to P. cinnamomi, only a few species are known to be resistant and control of this pathogen by chemicals is difficult and undesirable in natural systems. The major aim of our research is therefore to characterise natural resistance and determine which signalling pathways and defence responses are involved. Our examination of resistance is being approached at several levels, one of which is through the use of the model plant, Arabidopsis. Previously, Arabidopsis had been shown to display ecotypic variation in responses to P. cinnamomi and we are exploring this further in conjunction with the analysis of a bank of Arabidopsis defence pathway mutants for their responses to the pathogen. These experiments will provide a fundamental basis for further analysis of the defence responses of native plants. Native species (susceptible and resistant) are being assessed for their responses to P. cinnamomi at morphological, biochemical and molecular levels. This research also involves field-based studies of plants under challenge at various sites throughout Victoria, Australia. The focus of this field-based research is to assess the responses of individual species to P. cinnamomi in the natural environment with the goal of identifying individuals within susceptible species that display \u27resistance\u27. Understanding how plants are able to resist this pathogen will enable strategies to be developed to enhance species survival and to restore structure and biodiversity to the ecosystems under threat.<br /