478 research outputs found

    Geometrically Induced Gauge Structure on Manifolds Embedded in a Higher Dimensional Space

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    We explain in a context different from that of Maraner the formalism for describing motion of a particle, under the influence of a confining potential, in a neighbourhood of an n-dimensional curved manifold M^n embedded in a p-dimensional Euclidean space R^p with p >= n+2. The effective Hamiltonian on M^n has a (generally non-Abelian) gauge structure determined by geometry of M^n. Such a gauge term is defined in terms of the vectors normal to M^n, and its connection is called the N-connection. In order to see the global effect of this type of connections, the case of M^1 embedded in R^3 is examined, where the relation of an integral of the gauge potential of the N-connection (i.e., the torsion) along a path in M^1 to the Berry's phase is given through Gauss mapping of the vector tangent to M^1. Through the same mapping in the case of M^1 embedded in R^p, where the normal and the tangent quantities are exchanged, the relation of the N-connection to the induced gauge potential on the (p-1)-dimensional sphere S^{p-1} (p >= 3) found by Ohnuki and Kitakado is concretely established. Further, this latter which has the monopole-like structure is also proved to be gauge-equivalent to the spin-connection of S^{p-1}. Finally, by extending formally the fundamental equations for M^n to infinite dimensional case, the present formalism is applied to the field theory that admits a soliton solution. The resultant expression is in some respects different from that of Gervais and Jevicki.Comment: 52 pages, PHYZZX. To be published in Int. J. Mod. Phys.

    Case report: a case of intractable Meniere's disease treated with autogenic training

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    <p>Abstract</p> <p>Background</p> <p>Psychological stress plays an important role in the onset and course of Meniere's disease. Surgical therapy and intratympanic gentamicin treatment are options for cases that are intractable to conventional medical therapy. Psychotherapy, however, including autogenic training (AT), which can be used for general relaxation, is not widely accepted. This paper describes the successful administration of AT in a subject suffering from intractable Meniere's disease.</p> <p>Case presentation</p> <p>A 51-year-old male patient has suffered from fluctuating right sensorineural hearing loss with vertigo since 1994. In May 2002, he was first admitted to our hospital due to a severe vertigo attack accompanied by right sensorineural hearing loss. Spontaneous nystagmus toward the right side was observed. Since April 2004, he has experienced vertigo spells with right-sided tinnitus a few times per month that are intractable to conventional medical therapy. After four months, tympanic tube insertion was preformed in the right tympanic membrane. Intratympanic injection of dexamethasone was ineffective. He refused Meniett therapy and intratympanic gentamicin injection. In addition to his vertigo spells, he suffered from insomnia, tinnitus, and anxiety. Tranquilizers such as benzodiazepines and antidepressants such as serotonin selective re-uptake inhibitors (SSRIs) failed to stop the vertigo and only slightly improved his insomnia. In December 2006, the patient began psychological counseling with a psychotherapist. After brief psychological counseling along with cognitive behavior therapy (CBT), he began AT. He diligently and regularly continued his AT training in his home according to a written timetable. His insomnia, tinnitus, and vertigo spells disappeared within a few weeks after only four psychotherapy sessions. In order to master the six standard formulas of AT, he underwent two more sessions. Thereafter, he underwent follow-up for 9 months with no additional treatment. He is now free from drugs, including tranquilizers, and has continued AT. No additional treatment was performed. When we examined him <b>six </b>and nine months later for follow-up, he was free of vertigo and insomnia.</p> <p>Conclusion</p> <p>AT together with CBT can be a viable and palatable treatment option for Meniere's disease patients who are not responsive to other therapies.</p

    Reciprocal regulation of airway rejection by the inducible gas-forming enzymes heme oxygenase and nitric oxide synthase

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    Obliterative bronchiolitis (OB) develops insidiously in nearly half of all lung transplant recipients. Although typically preceded by a CD8+ T cell–rich lymphocytic bronchitis, it remains unresponsive to conventional immunosuppression. Using an airflow permissive model to study the role of gases flowing over the transplanted airway, it is shown that prolonged inhalation of sublethal doses of carbon monoxide (CO), but not nitric oxide (NO), obliterate the appearance of the obstructive airway lesion. Induction of the enzyme responsible for the synthesis of CO, heme oxygenase (Hmox) 1, increased carboxyhemoglobin levels and suppressed lymphocytic bronchitis and airway luminal occlusion after transplantation. In contrast, zinc protoporphyrin IX, a competitive inhibitor of Hmox, increased airway luminal occlusion. Compared with wild-type allografts, expression of inducible NO synthase (iNOS), which promotes the influx of cytoeffector leukocytes and airway graft rejection, was strikingly reduced by either enhanced expression of Hmox-1 or exogenous CO. Hmox-1/CO decreased nuclear factor (NF)-κB binding activity to the iNOS promoter region and iNOS expression. Inhibition of soluble guanylate cyclase did not interfere with the ability of CO to suppress OB, implicating a cyclic guanosine 3′,5′-monophosphate–independent mechanism through which CO suppresses NF-κB, iNOS transcription, and OB. Prolonged CO inhalation represents a new immunosuppresive strategy to prevent OB

    School closures and educational attainment in Ethiopia: Can extra classes help children to catch up?

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    Data availability statement: The data that support the findings of this study are available in Young Lives at https://beta. ukdataservice.ac.uk/datacatalogue/studies/study?id=7823&type=Data%20catalogue.ORCID: Fiona Carmichael https://orcid.org/0000-0002-7932-2410; Christian K. Darko https://orcid.org/0000-0002-1665-2594; Shireen Kanji https://orcid.org/0000-0003-3512-2596; Nicholas Vasilakos https://orcid.org/0000-0003-3279-2885.Copyright © 2022 The Authors. School closures impact children's attainment adversely, but understanding the effects of closures on children's attainment in lower-income countries is still limited. Addressing this deficit, this study examines how past school closures have impacted children's educational attainment in Ethiopia. The study uses individual student-level data from the Young Lives School Survey and standardised test scores in mathematics and language recorded at the start and end of the school year to model children's attainment. Multiple regression with propensity score matching is used to analyse how attainment over the school year is impacted by school closures for a matched sub-sample of 4842 students. The effectiveness of additional classes to make up for lost learning is also evaluated. Past school closures have had a detrimental effect on attainment in mathematics, but not literacy. Extra classes, specifically those that families do not pay for, have helped children in the past to recuperate lost learning and could serve this function post-Covid-19. Inequalities in learning outcomes, measured by Gini coefficients in educational attainment, are widened by school closures. Applying these results to the extensive school closures under Covid-19 furthers our understanding of the likely effects on academic attainment and can inform policy to mitigate the impact.https://beta. ukdataservice.ac.uk/datacatalogue/studies/study?id=7823&type=Data%20catalogu

    Learning-by-doing as an approach to teaching social entrepreneurship

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    Many studies have explored the use of learning-by-doing in higher education, but few have applied this to social entrepreneurship contexts and applications: this paper addresses this gap in the literature. Our programme involved students working with different stakeholders in an interactive learning environment to generate real revenue for social enterprises. Our results show that learning-by-doing enables students to develop their entrepreneurial skills and enhance their knowledge of social businesses. The findings also show that students became more effective at working in teams and in formulating and applying appropriate business strategies for the social enterprises. Overall, the learning-by-doing approach discussed in this paper is capable of developing the entrepreneurial skills of students, but there are challenges that need to be addressed if such an approach is to be effective

    The Horizontal Ice Nucleation Chamber (HINC) : INP measurements at conditions relevant for mixed-phase clouds at the High Altitude Research Station Jungfraujoch

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    In this work we describe the Horizontal Ice Nucleation Chamber (HINC) as a new instrument to measure ambient ice-nucleating particle (INP) concentrations for conditions relevant to mixed-phase clouds. Laboratory verification and validation experiments confirm the accuracy of the thermodynamic conditions of temperature (T) and relative humidity (RH) in HINC with uncertainties in T of ±0.4 K and in RH with respect to water (RHw) of ±1.5 %, which translates into an uncertainty in RH with respect to ice (RHi) of ±3.0 % at T &gt; 235 K. For further validation of HINC as a field instrument, two measurement campaigns were conducted in winters 2015 and 2016 at the High Altitude Research Station Jungfraujoch (JFJ; Switzerland, 3580 m a. s. l. ) to sample ambient INPs. During winters 2015 and 2016 the site encountered free-tropospheric conditions 92 and 79 % of the time, respectively. We measured INP concentrations at 242 K at water-subsaturated conditions (RHw = 94 %), relevant for the formation of ice clouds, and in the water-supersaturated regime (RHw = 104 %) to represent ice formation occurring under mixed-phase cloud conditions. In winters 2015 and 2016 the median INP concentrations at RHw = 94 % was below the minimum detectable concentration. At RHw = 104 %, INP concentrations were an order of magnitude higher, with median concentrations in winter 2015 of 2.8 per standard liter (std L−1; normalized to standard T of 273 K and pressure, p, of 1013 hPa) and 4.7 std L−1 in winter 2016. The measurements are in agreement with previous winter measurements obtained with the Portable Ice Nucleation Chamber (PINC) of 2.2 std L−1 at the same location. During winter 2015, two events caused the INP concentrations at RHw = 104 % to significantly increase above the campaign average. First, an increase to 72.1 std L−1 was measured during an event influenced by marine air, arriving at the JFJ from the North Sea and the Norwegian Sea. The contribution from anthropogenic or other sources can thereby not be ruled out. Second, INP concentrations up to 146.2 std L−1 were observed during a Saharan dust event. To our knowledge this is the first time that a clear enrichment in ambient INP concentration in remote regions of the atmosphere is observed during a time of marine air mass influence, suggesting the importance of marine particles on ice nucleation in the free troposphere

    Advancing Team Cohesion: Using an Escape Room as a Novel Approach

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    Objective: An escape room was used to study teamwork and its determinants, which have been found to relate to the quality and safety of patient care delivery. This pilot study aimed to explore the value of an escape room as a mechanism for improving cohesion among interdisciplinary healthcare teams. Methods: This research was conducted at a nonprofit medical center in Southern California. All participants who work on a team were invited to participate. Authors employed an interrupted within-subjects design, with two pre- and post- escape room questionnaires related to two facets of group cohesion: (belonging – (PGC-B) and morale (PGC-M)). Participants rated their perceptions of group cohesion before, after, and one-month after the escape room. The main outcome measures included PGC-B/M. Results: Sixty-two teams participated (n 280 participants) of which 31 teams (50%) successfully “escaped” in the allotted 45 minutes. There was a statistically significant difference in PGC between the three time periods, F(4, 254) 24.10, p \u3c .001; Wilks’ K .725; partial g2 .275. Results indicated significantly higher scores for PGC immediately after the escape room and at the one-month follow-up compared to baseline. Conclusions: This work offers insights into the utility of using an escape room as a team building intervention in interprofessional healthcare teams. Considering the modifiability of escape rooms, they may function as valuable team building mechanisms in healthcare. More work is needed to determine how escape rooms compare to more traditional team building curriculums

    Identifying and addressing conflicting results across multiple discordant systematic reviews on the same question: protocol for a replication study of the Jadad algorithm

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    Introduction An increasing growth of systematic reviews (SRs) presents notable challenges for decision-makers seeking to answer clinical questions. In 1997, an algorithm was created by Jadad to assess discordance in results across SRs on the same question. Our study aims to (1) replicate assessments done in a sample of studies using the Jadad algorithm to determine if the same SR would have been chosen, (2) evaluate the Jadad algorithm in terms of utility, efficiency and comprehensiveness, and (3) describe how authors address discordance in results across multiple SRs. Methods and analysis We will use a database of 1218 overviews (2000-2020) created from a bibliometric study as the basis of our search for studies assessing discordance (called discordant reviews). This bibliometric study searched MEDLINE (Ovid), Epistemonikos and Cochrane Database of Systematic Reviews for overviews. We will include any study using Jadad (1997) or another method to assess discordance. The first 30 studies screened at the full-text stage by two independent reviewers will be included. We will replicate the authors' Jadad assessments. We will compare our outcomes qualitatively and evaluate the differences between our Jadad assessment of discordance and the authors' assessment. Ethics and dissemination No ethics approval was required as no human subjects were involved. In addition to publishing in an open-access journal, we will disseminate evidence summaries through formal and informal conferences, academic websites, and across social media platforms. This is the first study to comprehensively evaluate and replicate Jadad algorithm assessments of discordance across multiple SRs
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