1,006 research outputs found

    Dynamics of Systems With Hamiltonian Monodromy

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    A system is said to have monodromy if, when we carry the system around a closed circuit, it does not return to its initial state. The simplest example is the square-root function in the complex plane. A Hamiltonian system is said to have Hamiltonian monodromy if its fundamental action-angle loops do not return to their initial topological state at the end of a closed circuit. These changes in topology of angle loops carry through to other aspects of these systems, including the classical dynamics of families of trajectories, quantum spectra and even wavefunctions. This topological change in the evolution of a loop of classical trajectories has been observed experimentally for the rst time, using an apparatus consisting of a spherical pendulum subject to magnetic potentials and torques. Presented in this dissertation are the details of this experiment, as well as theoretical calculations on a novel system: a double welled Mexican-hat system with two monodromy points. This is part of a more general research program that is concerned with the Lagrangian torus bration of the phase spaces of integrable Hamiltonian systems. It is in this way the calculations on the double welled system are carried out. in this dissertation, static and dynamical manifestations of monodromy are shown to exist for this system. It has been shown previously that corresponding topological changes occur in wavefunctions of systems with monodromy. Here it is shown that results of quantum wavefunction monodomy carry over intuitively

    Combining social network analysis and the NATO Approach Space to define agility. Topic 2: networks and networking

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    This paper takes the NATO SAS-050 Approach Space, a widely accepted model of command and control, and gives each of its primary axes a quantitative measure using social network analysis. This means that the actual point in the approach space adopted by real-life command and control organizations can be plotted along with the way in which that point varies over time and function. Part 1 of the paper presents the rationale behind this innovation and how it was subject to verification using theoretical data. Part 2 shows how the enhanced approach space was put to use in the context of a large scale military command post exercise. Agility is represented by the number of distinct areas in the approach space that the organization was able to occupy and there was a marked disparity between where the organization thought it should be and where it actually was, furthermore, agility varied across function. The humans in this particular scenario bestowed upon the organization the levels of agility that were observed, thus the findings are properly considered from a socio-technical perspective

    Mandatory SARS-CoV-2 Vaccinations in K-12 Schools, Colleges/Universities, and Businesses

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    The Centers for Disease Control and Prevention (CDC) recently issued guidance that fully vaccinated individuals can safely remove masks and end social distancing in most indoor settings. Educational facilities and businesses are faced with whether and how to differentiate between vaccinated and unvaccinated individuals, including requiring proof of vaccination. Mandatory vaccination has historically served as a tool to reach and sustain high immunization coverage and to prevent transmission in K-12 schools, colleges/universities, and health care facilities. Vaccine mandates could extend to workers and customers in businesses to ensure safer environments. This Viewpoint examines the epidemiologic, public health, and legal considerations for mandatory SARS-CoV-2 vaccinations in each setting

    Keabsahan Perubahan Status Hukum Desa Werwawan Menjadi Dusun Werwawan Di Kabupaten Maluku Barat Daya

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    The transfer of the village government center from Werwawan Village to Letoda Hamlet without going through a legal product, namely a Regional Regulation. This research is a normative juridical research, and then examines and knows the answers to this problem through a concept approach, statutory approach and case approach, then from the results of the description conclusions and suggestions can be drawn. The results showed that the formation of Letoda Hamlet to become an autonomous village and the transition of legal status from Werwawan Village to a hamlet were not in accordance with the substance and legal procedures in force, including the discretion of the Deputy Regent of West Southeast Maluku to the Head of Letoda Village to move the government administration center from Werwawan Village to Letoda Hamlet which was then accompanied by Letoda Hamlet to become an autonomous village and Werwawan Village to become a hamlet which did not have legal validity and had no binding legal force and the transition of legal status from Werwawan Village to Werwawan Hamlet had no legal status. Legal amendments in the concept of administrative law, material/factual actions and legal actions taken by the Deputy Regent of West Southeast Maluku which have implications for Letoda Hamlet becoming an autonomous village and Werwawan Village becoming a hamlet in principle are government actions that are not based on law so that there are legal consequences of the government's actions so that legal actions can give rise to legal consequences administratively and therefore Letoda Hamlet which has become an autonomous village and Werwawan Village which has become a hamlet does not have legal validity so it can be annulled

    A software solution for recording circadian oscillator features in time-lapse live cell microscopy

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    BACKGROUND: Fluorescent and bioluminescent time-lapse microscopy approaches have been successfully used to investigate molecular mechanisms underlying the mammalian circadian oscillator at the single cell level. However, most of the available software and common methods based on intensity-threshold segmentation and frame-to-frame tracking are not applicable in these experiments. This is due to cell movement and dramatic changes in the fluorescent/bioluminescent reporter protein during the circadian cycle, with the lowest expression level very close to the background intensity. At present, the standard approach to analyze data sets obtained from time lapse microscopy is either manual tracking or application of generic image-processing software/dedicated tracking software. To our knowledge, these existing software solutions for manual and automatic tracking have strong limitations in tracking individual cells if their plane shifts. RESULTS: In an attempt to improve existing methodology of time-lapse tracking of a large number of moving cells, we have developed a semi-automatic software package. It extracts the trajectory of the cells by tracking theirs displacements, makes the delineation of cell nucleus or whole cell, and finally yields measurements of various features, like reporter protein expression level or cell displacement. As an example, we present here single cell circadian pattern and motility analysis of NIH3T3 mouse fibroblasts expressing a fluorescent circadian reporter protein. Using Circadian Gene Express plugin, we performed fast and nonbiased analysis of large fluorescent time lapse microscopy datasets. CONCLUSIONS: Our software solution, Circadian Gene Express (CGE), is easy to use and allows precise and semi-automatic tracking of moving cells over longer period of time. In spite of significant circadian variations in protein expression with extremely low expression levels at the valley phase, CGE allows accurate and efficient recording of large number of cell parameters, including level of reporter protein expression, velocity, direction of movement, and others. CGE proves to be useful for the analysis of widefield fluorescent microscopy datasets, as well as for bioluminescence imaging. Moreover, it might be easily adaptable for confocal image analysis by manually choosing one of the focal planes of each z-stack of the various time points of a time series. AVAILABILITY: CGE is a Java plugin for ImageJ; it is freely available at: http://bigwww.epfl.ch/sage/soft/circadian/

    Mandating COVID-19 Vaccines

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    Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines hold promise to control the pandemic, and help restore normal social and economic life. The Food and Drug Administration (FDA) has granted emergency use authorization (EUA) for 2 mRNA vaccines and will likely issue full biologics licenses in the coming months. Anticipating vaccine scarcity, the Advisory Committee on Immunization Practice (ACIP) published guidance on vaccine priorities.Data show 95% efficacy for vaccines granted an EUA, but even highly effective vaccines cannot curb the pandemic without high population coverage and maintenance of other mitigation strategies. Recent data from 1,676 adults surveyed November 30-December 8, 2020 found that when a COVID-19 vaccine is approved and widely available: 34% would get it as soon as possible; 39% would wait; 9% would only get it if required for work/school; 15% would definitely not get it. Black persons, at high risk of infection and hospitalization, are less likely to report vaccine intent with only 20% reporting they would get the vaccine soon and 52% intending to wait. Intent to vaccinate has changed substantially over time and is likely to evolve. In this JAMA Viewpoint, we examine whether vaccine mandates would be lawful and ethical, and whether they could boost vaccine uptake
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