1,183 research outputs found

    Black Hole Mass Formula Is a Vanishing Noether Charge

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    The Noether current and its variation relation with respect to diffeomorphism invariance of gravitational theories have been derived from the horizontal variation and vertical-horizontal bi-variation of the Lagrangian, respectively. For Einstein's GR in the stationary, axisymmetric black holes, the mass formula in vacuum can be derived from this Noether current although it definitely vanishes. This indicates that the mass formula of black holes is a vanishing Noether charge in this case. The first law of black hole thermodynamics can also be derived from the variation relation of this vanishing Noether current.Comment: 7 page

    Improve The Logical Reasoning Ability of Primary School Students by Using Video Learning Assistant Teaching

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    Under the current situation of epidemic prevention and control, to ensure the continuous progress of student learning, Chinese Ministry of Education put forward the initiative of "suspension of classes without suspension of school". Primary and secondary schools have adopted online learning at home for students to "open schools in the cloud. There is a big difference between online learning and classroom learning. In this process, problems such as increased teaching burden of teachers, lack of interaction between teachers and students, and students' lack of active learning are also exposed. Video learning are a new type of teaching resource. It can improve the efficiency of primary school mathematics teaching by using video learning reasonably. Based on the above analysis, the purpose of this research is to investigate the development of primary school students' logical reasoning ability through the use of video leanings for auxiliary teaching. The research method adopts the experimental method and is divided into the experimental class and control class. The subjects of the study were 72 students from a primary school in Indonesia. Experimental results show that video learning for auxiliary teaching can effectively develop students' logical reasoning ability

    Patients with myasthenia gravis with acute onset of dyspnea: predictors of progression to myasthenic crisis and prognosis

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    Background: Life-threatening myasthenic crisis (MC) occurs in 10–20% of the patients with myasthenia gravis (MG). It is important to identify the predictors of progression to MC and prognosis in the patients with MG with acute exacerbations. Objective: This study aimed to explore the predictors of progression to MC in the patients with MG with acute onset of dyspnea and their short-term and long-term prognosis. Methods: This study is a retrospective cohort study. We collected and analyzed data on all the patients with MG with acute dyspnea over a 10-year period in a single center using the univariate and multivariate analysis. Results: Eighty-six patients with MG were included. In their first acute dyspnea episodes, 36 (41.9%) episodes eventually progressed to MC. A multivariate analysis showed that the early-onset MG (adjusted OR: 3.079, 95% CI 1.052–9.012) and respiratory infection as a trigger (adjusted OR: 3.926, 95% CI 1.141–13.510) were independent risk factors for the progression to MC, while intravenous immunoglobulin (IVIg) treatment prior to the mechanical ventilation (adjusted OR: 0.253, 95% CI 0.087–0.732) was a protective factor. The prognosis did not significantly differ between the patients with and without MC during the MG course, with a total of 45 (52.3%) patients reaching post-intervention status better than minimal manifestations at the last follow-up. Conclusion: When treating the patients with MG with acute dyspnea, the clinicians should be aware of the risk factors of progression to MC, such as early-onset MG and respiratory infection. IVIg is an effective treatment. With proper immunosuppressive therapy, this group of patients had an overall good long-term prognosis

    mHealth in China and the United States: How Mobile Technology is Transforming Healthcare in the World's Two Largest Economies

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    In this paper, we explore ways mobile technology can help with these difficulties. Specifically, we look at avenues through which mobile devices boost productivity, aid communications, and help providers improve affordability, access, and treatment. Using data drawn from China and the United States as well as global trends, we look at recent developments andemerging opportunities in mobile health, or mHealth. We argue that mobile technology assists patients, health providers, and policymakers in several different respects. It helps patients by giving them tools to monitor their health conditions and communicate those results to physicians. It enables health providers to connect with colleagues and offers alternative sources of information for patients. It is also an important tool to inform policymakers on health delivery and medical outcomes

    Acrylato[tris­(1-methyl-1H-benzimidazol-2-ylmeth­yl)amine]cobalt(II) perchlorate–dimethyl­formamide–methanol (2/2/3)

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    In the title complex, [Co(C3H3O2)(C27H27N7)]ClO4·C3H7NO·1.5CH4O, the CoII ion is five-coordinated by four N atoms from a tris­(1-methyl-1H-benzimidazol-2-ylmeth­yl)amine (mentb) ligand and one O atom from an acrylate ligand in a distorted trigonal–bipyramidal geometry with approximate mol­ecular C 3 symmetry. The atoms of the acrylate ligand are disordered over two sites, with approximate occupancies of 0.90 and 0.10. In addition, the solvent hemimethanol mol­ecule is disordered over two positions with equal occupancies. The crystal structure is stabilized by weak intermolecular O—H⋯O hydrogen bonds

    Association between clinical factors and result of immune checkpoint inhibitor related myasthenia gravis: a single center experience and systematic review

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    Background: Neurological immune-related adverse events (nirAEs) are rare toxicities of immune-checkpoint inhibitors (ICI). With the increase use of ICIs, incidence of nirAEs is growing, among which ICI related MG (irMG) is causing high fatality rate. Given the limited evidence, data from a large cohort of patients with irMG is needed to aid in recognition and management of this fatal complication. Objective: This study aimed to summarize clinical characteristics of irMG and explore predictors of irMG clinical outcome. Methods: We summarized our institution's patients who were diagnosed as irMG between Sep 2019 and Oct 2021. We systematically reviewed the literature through Oct 2021 to identify all similar reported patients who met inclusion criteria. As the control group, patients with idiopathic MG were used. We collected data on clinical features, management, and outcomes of both irMG and idioMG cases. Further statistical analysis was conducted. Results: Sixty three irMG patients and 380 idioMG patients were included in the final analysis. For irMG patients, six were from our institution while the rest 57 were from reported cases. The average age of irMG patients is 70.16 years old. Forty three were male. Average time from first ICI injection to symptom onset was 5.500 weeks. Eleven patients had a past history of MG. Higher MGFA classification and higher QMGS rates were observed in irMG patients compared to idioMG patients. For complication, more irMG patients had myositis or myocarditis overlapping compared to idioMG patients. The most commonly used treatment was corticosteroids for both idioMG and irMG. Twenty one patients (35%) with irMG had unfavorable disease outcome. Single variate and multivariate binary logistic regression proved that association with myocarditis, high MGFA classification or QMGS rates at first visit were negatively related to disease outcome in irMG patients. Conclusion: irMG is a life-threatening adverse event. irMG has unique clinical manifestations and clinical outcome compared to idioMG. When suspicious, early evaluation of MGFA classification, QMGS rates and myositis/myocarditis evaluation are recommended
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