Hartle-Hawking state is a maximum of entanglement entropy

It is shown that the Hartle-Hawking state of a scalar field is a maximum of entanglement entropy in the space of pure quantum states satisfying the condition that backreaction is finite. In other words, the Hartle-Hawking state is a curved-space analogue of the EPR state, which is also a maximum of entanglement entropy.Comment: Latex, 4 pages, Some comments are added on the "small backreaction condition

Acute Stroke: Present and Future of Catheter-Based Interventions

Abstract : Acute ischemic stroke is a major cause of morbidity and mortality in industrialized nations. The sequel of stroke ranges from mild to severe disability and even death. Since the impairment may be permanent, the costs to society from work incapacity and the need for long-term care can be high. Additionally, the burden of suffering associated with the disease may have devastating effects on individuals and families. Following the occlusion of a cerebral vessel, the full extent of the infarction may not become clinically and radiologically apparent until days after. By then, the surrounding watershed zone, or penumbra, either survives or succumbs to necrosis over time. The natural history of this "tissue at risk” is determined by two factors: the collateralization from other vascular territories and the possible occurrence of spontaneous recanalization of the occluded vessel. The current treatment options for acute ischemic stroke are aiming at an early and sustained restoration of flow to the penumbra. The effect of the treatment is therefore time-dependent and the neurologic outcome is a function of the time span between onset of symptoms and recanalization therapy as well as of the recanalization rate associated with a specific treatment. This report summarizes the results of the major trials on catheter-based interventions, either using thrombolytic drugs or novel mechanical approaches being developed to treat patients with acute ischemic strok

Low awareness of transient ischemic attacks and risk factors of stroke in a Swiss urban community

Background and purpose: Time delays from stroke onset to arrival at the hospital are the main obstacles for widespread use of thrombolysis. In order to decrease the delays, educational campaigns try to inform the general public how to act optimally in case of stroke. To determine the content of such a campaign, we assessed the stroke knowledge in our population. Methods: The stroke knowledge was studied by means of a closed-ended questionnaire. 422 randomly chosen inhabitants of Bern, Switzerland, were interviewed. Results: The knowledge of stroke warning signs (WS) was classified as good in 64.7%. A good knowledge of stroke risk factors (RF) was noted in 6.4%. 4.2% knew both the WS and the RF of stroke indicating a very good global knowledge of stroke. Only 8.3% recognized TIA as symptoms of stroke resolving within 24hours, and only 2.8% identified TIA as a disease requiring immediate medical help. In multivariate analysis being a woman, advancing age, and having an afflicted relative were associated with a good knowledge of WS (p=0.048, p<0.001 and p=0.043). Good knowledge of RF was related to university education (p<0.001). The good knowledge of TIA did not depend on age, sex, level of education or having an afflicted relative. Conclusions: The study brings to light relevant deficits of stroke knowledge in our population. A small number of participants could recognize TIA as stroke related symptoms resolving completely within 24hours. Only a third of the surveyed persons would seek immediate medical help in case of TIA. The information obtained will be used in the development of future educational campaign

Effective Confining Potential of Quantum States in Disordered Media

The amplitude of localized quantum states in random or disordered media may exhibit long-range exponential decay. We present here a theory that unveils the existence of an effective potential which finely governs the confinement of these states. In this picture, the boundaries of the localization subregions for low energy eigenfunctions correspond to the barriers of this effective potential, and the long-range exponential decay characteristic of Anderson localization is explained as the consequence of multiple tunneling in the dense network of barriers created by this effective potential. Finally, we show that Weyl’s formula based on this potential turns out to be a remarkable approximation of the density of states for a large variety of one-dimensional systems, periodic or random.National Science Foundation (U.S.) (Grant DMS-1069225)National Science Foundation (U.S.) (Grant DMS-1500771

The landscape law for tight binding Hamiltonians

The present paper extends the landscape theory pioneered in [FM, ADFJM2, DFM] to the tight-binding Schr\"odinger operator on $\Z^d$. In particular, we establish upper and lower bounds for the integrated density of states in terms of the counting function based upon the localization landscape

Stroke lesion size:Still a useful biomarker for stroke severity and outcome in times of high-dimensional models

BACKGROUND The volumetric size of a brain lesion is a frequently used stroke biomarker. It stands out among most imaging biomarkers for being a one-dimensional variable that is applicable in simple statistical models. In times of machine learning algorithms, the question arises of whether such a simple variable is still useful, or whether high-dimensional models on spatial lesion information are superior. METHODS We included 753 first-ever anterior circulation ischemic stroke patients (age 68.4±15.2 years; NIHSS at 24 h 4.4±5.1; modified Rankin Scale (mRS) at 3-months median[IQR] 1[0.75;3]) and traced lesions on diffusion-weighted MRI. In an out-of-sample model validation scheme, we predicted stroke severity as measured by NIHSS 24 h and functional stroke outcome as measured by mRS at 3 months either from spatial lesion features or lesion size. RESULTS For stroke severity, the best regression model based on lesion size performed significantly above chance (p < 0.0001) with R2 = 0.322, but models with spatial lesion features performed significantly better with R2 = 0.363 (t(752) = 2.889; p = 0.004). For stroke outcome, the best classification model based on lesion size again performed significantly above chance (p < 0.0001) with an accuracy of 62.8%, which was not different from the best model with spatial lesion features (62.6%, p = 0.80). With smaller training data sets of only 150 or 50 patients, the performance of high-dimensional models with spatial lesion features decreased up to the point of being equivalent or even inferior to models trained on lesion size. The combination of lesion size and spatial lesion features in one model did not improve predictions. CONCLUSIONS Lesion size is a decent biomarker for stroke outcome and severity that is slightly inferior to spatial lesion features but is particularly suited in studies with small samples. When low-dimensional models are desired, lesion size provides a viable proxy biomarker for spatial lesion features, whereas high-precision prediction models in personalised prognostic medicine should operate with high-dimensional spatial imaging features in large samples

Vascular Diseases of the Spinal Cord: A Review

Opinion statement: • In acute spinal cord ischemia syndrome (ASCIS), treatment recommendations are derived from data of cerebral ischemic stroke, atherosclerotic vascular disease and acute spinal cord injury. Besides acute management, secondary prevention is of major importance. Pathologies affecting the aorta as well as underlying cerebrovascular conditions should be treated whenever possible. • ASCIS may occur after aortic surgery, less often after thoracic endovascular aortic repair (TEVAR). Protocols are proposed. • Acute spinal cord hemorrhage can be treated surgically and/or pharmacologically. • Symptomatic treatment in patients with a spinal cord lesion is of major importance. Depending on level and extension of the lesion, there is a risk for systemic and neurological complications, which may be life-threatening. • Each spinal vascular malformation is a unique lesion that needs an individualized treatment algorithm. In case of a symptomatic vascular malformation, endovascular intervention is the primary treatment option. • Spinal dural Arteriovenous fistula (AVF) may be treated endovascularly or surgically. If preoperative localization of the fistula is possible, surgery is feasible with a low complication rate. In comparison, endovascular approaches are less invasive. • Spinal AVM are rather treated endovascularly than surgically or in a stepwise multidisciplinary approach. • Symptomatic and exophytic spinal cavernous angiomas should be treated surgically. Deep spinal cavernous angiomas that are asymptomatic or only show mild symptoms can be observe

Cerebral Venous Sinus Thrombosis Associated with Vaccine-Induced Thrombotic Thrombocytopenia—A Narrative Review

In March 2021, cerebral venous sinus thrombosis and thrombocytopenia after vaccination with adenovirus-based vaccine against SARS-CoV-2 were first reported. The underlining condition has been termed vaccine-induced immune thrombocytopenia (VITT). Anti-platelet factor 4 antibodies have been proposed as a central component of the pathomechanism. Treatment recommendations entailed immunomodulation with intravenous immunoglobulins, avoidance of heparins and avoidance of platelet transfusions. Although mortality from VITT-associated cerebral venous sinus thrombosis has decreased over time, it remains high. The aim of this narrative review is to describe different aspects of this disease according to the current state of knowledge

Interkulturelle Kompetenz in der Sächsischen Wirtschaft

Das Working Paper Nr. 1 basiert auf der Studie „Ergebnisse der Situationsanalyse“, welche von der Technischen Universität Dresden, Fakultät für Erziehungswissenschaften, Institut für Berufspädagogik, Professur für Didaktik des beruflichen Lernens (Prof. Dr. paed. habil. Hanno Hortsch, Dipl.-Berufspäd. Marcel Köhler, Lars Leidl M.A., M.Sc.) im Auftrag der Staatlichen Studienakademie Breitenbrunn durchgeführt wurde. Die vollständige Studie, die für den vorliegenden Bericht durch die Herausgeberin gekürzt und redaktionell weiterverarbeitet wurde, wird nicht als eigene Publikation der Öffentlichkeit zugänglich gemacht. Diese Studie und das Working Paper sind Bestandteil des Projektes „Zusatzqualifikation zur Förderung der interkulturellen Kompetenz von Studierenden der Berufsakademie Sachsen“, welches aus Mitteln des Europäischen Sozialfonds (ESF) und des Freistaates Sachsen gefördert wird.:1 Ziele und Inhalte der „Zusatzqualifikation Interkulturelle Kompetenz“ 2 Gegenstand und Methode der Situationsanalyse 3 Ergebnisse der Situationsanalyse 3.1 Vorhandene Unternehmensstrukturen 3.2 Stellenwert und Bedeutung von interkulturell qualifiziertem Personal 3.3 Anforderungen an interkulturell qualifiziertes akademisches Fachpersonal 3.4 Inhalte der Zusatzqualifikation Interkulturelle Kompetenz 3.5 Zielländer/-kulturen/-regionen in der Konzeption der Zusatzqualifikation 3.6 Didaktisch-methodische Empfehlungen für die Konzeption 3.7 Befragung der Studierenden des Studiengangs Industrie 4 Fazi

Viewpoint: Evaluating the impact of malaria control efforts on mortality in sub-Saharan Africa

OBJECTIVE To describe an approach for evaluating the impact of malaria control efforts on malaria-associated mortality in sub-Saharan Africa, where disease-specific mortality trends usually cannot be measured directly and most malaria deaths occur among young children. METHODS Methods for evaluating changes in malaria-associated mortality are examined; advantages and disadvantages are presented. RESULTS All methods require a plausibility argument - i.e., an assumption that mortality reductions can be attributed to programmatic efforts if improvements are found in steps of the causal pathway between intervention scale-up and mortality trends. As different methods provide complementary information, they can be used together. We recommend following trends in the coverage of malaria control interventions, other factors influencing childhood mortality, malaria-associated morbidity (especially anaemia), and all-cause childhood mortality. This approach reflects decreases in malaria's direct and indirect mortality burden and can be examined in nearly all countries. Adding other information can strengthen the plausibility argument: trends in indicators of malaria transmission, information from demographic surveillance systems and sentinel sites where malaria diagnostics are systematically used, and verbal autopsies linked to representative household surveys. Health facility data on malaria deaths have well-recognized limitations; however, in specific circumstances, they could produce reliable trends. Model-based predictions can help describe changes in malaria-specific burden and assist with program management and advocacy. CONCLUSIONS Despite challenges, efforts to reduce malaria-associated mortality in Africa can be evaluated with trends in malaria intervention coverage and all-cause childhood mortality. Where there are resources and interest, complementary data on malaria morbidity and malaria-specific mortality could be added