441 research outputs found
Eisenhart Lift of --Dimensional Mechanics
The Eisenhart lift is a variant of geometrization of classical mechanics with
degrees of freedom in which the equations of motion are embedded into the
geodesic equations of a Brinkmann-type metric defined on -dimensional
spacetime of Lorentzian signature. In this work, the Eisenhart lift of
-dimensional mechanics on curved background is studied. The corresponding
-dimensional metric is governed by two scalar functions which are just the
conformal factor and the potential of the original dynamical system. We derive
a conformal symmetry and a corresponding quadratic integral, associated with
the Eisenhart lift. The energy--momentum tensor is constructed which, along
with the metric, provides a solution to the Einstein equations. Uplifts of
-dimensional superintegrable models are discussed with a particular emphasis
on the issue of hidden symmetries. It is shown that for the -dimensional
Darboux--Koenigs metrics, only type I can result in Eisenhart lifts which
satisfy the weak energy condition. However, some physically viable metrics with
hidden symmetries are presented.Comment: 20 page
Utilizing Moving Vehicles as Sensors for Bridge Condition Screening – A Laboratory Verification
Health condition monitoring of bridge structures is attracting considerable attention, conventionally relying on visual inspection, and measurement-based methods that involve sensors installed directly on bridges. In recent years, drive-by monitoring methods that treat moving vehicles as moving sensors have been proposed as alternatives; these methods aim to be lowcost, mobile, and target fast bridge condition screening. In this study, we address the current lack of sufficient experimental verification of such methods. Laboratory experiments were conducted using a test vehicle system equipped with accelerometers in order to verify the practical feasibility of three drive-by methods: (1) bridge-frequency extraction using the Fourier spectrum of a vehicle’s dynamic response, (2) damage detection using the change in a vehicle’s spectral distribution pattern, and (3) roadway surface profile identification
Predictive Model for Adverse Events and Immune Response Based on the Production of Antibodies After the Second-Dose of the BNT162b2 mRNA Vaccine
Background: The BNT162b mRNA vaccine for coronavirus disease 2019, which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), mimics the immune response to natural infection. Few studies have predicted the adverse effects (AEs) after the second-dose vaccination. We present a predictive model for AEs and immune response after the second-dose of the BNT162b mRNA vaccine. Methods: To predict AEs, 282 healthcare workers (HCWs) were enrolled in this prospective observational study. The classification and regression tree (CART) model was established, and its predictive efficacy was assessed. To predict immune response, 282 HCWs were included in the analysis. Moreover, the factors affected by anti-SARS-CoV-2 spike protein RBD antibody (s-IgG) were evaluated using serum samples collected 2 months after the second-dose vaccination. The s-IgG level was assessed using Lumipulse G1200. Multiple regression analyses were conducted to evaluate variables associated with anti-s-IgG titer levels. Results: The most common AEs after the second-dose vaccination were pain (87.6%), redness (17.0%) at the injection site, fatigue (68.8%), headache (53.5%), and fever (37.5%). Based on the CART model, headache after the first-dose vaccination and age < 30 years were identified as the first and second discriminators for predicting the headache after the second-dose vaccination, respectively. In the multiple linear regression model, anti-s-IgG titer levels were associated with age, female sex, and AEs including headache and induration at the injection site after the second-dose vaccination. Conclusion: Headache after the first-dose vaccination can be a predictor of headache after the second-dose vaccination, and AEs are indicators of immune response
Physical Characteristics of Injection Site Pain After COVID-19 mRNA BNT162b2 Vaccination
Background: BNT162b2, an mRNA COVID-19 vaccine, was launched in many countries as an intramuscular vaccination for COVID-19 infection. Few studies have assessed the physical indications of pain at the immunization site. This study aimed to characterize pain at the injection site and investigate morphological attributes using ultrasound. Methods: Forty-three of 211 healthcare workers who received a second dose of BNT162b2 between February 2021 and March 2021 were enrolled in the study. The mean age of the subjects was 40 years. We evaluated patients’ pain at the injection site using the Numerical Rating Pain Scale (NRPS). We also assessed the thickness of the deltoid muscle fascia at the injection site by ultrasound. Bayesian robust correlation was employed to explore the relationship between the pain intensity scores and ultrasound measurements. Results: All eligible subjects complained of pain at the injection site. A median pain onset of 8 hours post-vaccination and a median peak intensity score of 4 were reported. Onset of relief occurred after 2 days. Ultrasound images demonstrated a 2.5-fold increase in fascia thickness at the injection site without intramuscular echogenicity change in all subjects. A correlation was established between the NRPS score and the non-injection-to-injection-side ratio of fascia thickness at the injection site (rho = 0.66). Conclusion: A sore arm was the most prevalent side effect of BNT162b2 vaccination and could be attributed to temporal fasciitis
Experiences of Negotiations for Improving Research Environment and Burnout among Young Physician Researchers in Japan
Physician scientists in Japan are often too busy to be sufficiently involved in research work. This cross-sectional study aimed to investigate their experiences negotiating with their superiors to improve their research environment and determine its relationship with psychological burnout. Among 1790 physician awardees of Grants-in-Aid for Young Scientists in 2014-2015, 490 responded (response rate 27.4%) and 408 were eligible for analysis. Outcome measures included two negotiation experiences: for reduction of clinical duty hours/promotion opportunities and for increased space or equipment/increased research budget. The main explanatory variables were personal, patient-related, and work-related burnout measured by the Copenhagen Burnout Inventory. The percentages of the above-mentioned two types of negotiations were 20-24% in women and 17-20% in men. Multivariable stepwise logistic regression analyses demonstrated that (1) the negotiation for reduction of clinical duty hours/promotion opportunities was significantly associated with physician scientists who had a short amount of weekly research time and high patient-related burnout score, and (2) the negotiation for increased space or equipment/increased research budget was significantly associated with older age, single status, and high personal and patient-related burnout scores. High burnout is related to negotiation experiences among physician researchers in Japan
Expression of fractalkine and its receptor, CX3CR1, in atopic dermatitis: Possible contribution to skin inflammation
Background: Fractalkine (FKN) induces activation and adhesion of leukocytes expressing its receptor, CX3CR1. FKN is released from the cell surface through proteolytic cleavage as soluble FKN (sFKN). Objective: We sought to assess FKN and CX3CR1 expression in the skin, serum sFKN levels, and CX3CR1 expression on blood leukocytes in patients with atopic dermatitis (AD). Methods: FKN and CX3CR1 expression in the skin was examined immunohistochemically. mRNA expression of FKN, thymus and activation-regulated chemokine, and macrophage-derived chemokine in the skin was assessed by means of real-time RT-PCR. Serum sFKN levels were assessed by using ELISA. Blood leukocytes were stained for CX3CR1 by means of flow cytometric analysis. Results: FKN was strongly expressed on endothelial cells in skin lesions of patients with AD and psoriasis but not in normal skin. FKN mRNA levels in AD lesional skin increased to a similar extent to thymus and activation-regulated chemokine and macrophage-derived chemokine mRNA levels. CX3CR1-expressing cells in the affected skin of patients with AD or psoriasis increased compared with those in normal skin. Serum sFKN levels were increased in patients with AD but not in patients with psoriasis relative to levels in healthy control subjects. Serum sFKN levels were associated with the disease severity and decreased with the improvement of skin lesions in patients with AD. CX3CR1+ cell frequencies and CX3CR1 expression levels were decreased in CD8+ T cells, monocytes, and natural killer cells from patients with AD, but this was not observed in patients with psoriasis. Conclusions: These results suggest that through functions in both membrane-bound and soluble forms, FKN plays an important role in the trafficking of CX3CR1+ leukocytes during the inflammation caused by AD
Lateral Earth Pressure on Retaining Wall
President Cheryl B. Schrader discuses the recent report by a variety of Ohio higher institutions. The study assesses the economic impact of higher education in Ohio. She gives many details about the impact that Wright State has on the economy
Development of an Autonomous Vehicle Equipped with a Broadband Ultrasonic Sensor (Thermophone) for Engineering Verification of the Bats Jamming Avoidance Behavior
The 11th International Symposium on Adaptive Motion of Animals and Machines. Kobe University, Japan. 2023-06-06/09. Adaptive Motion of Animals and Machines Organizing Committee.Poster Session P3
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