1,499 research outputs found
Einstein Structure of Squashed Four-Spheres
It is known that the moduli space of Einstein structures is an isolated point
so that an Einstein structure has no infinitesimal Einstein deformations. We
examine the rigidity of the Einstein structure by considering deformations of
the round four-sphere . We show that any deformation of the round
four-sphere causes it to deviate from the Einstein structure,
except trivial deformations at most only changing the size of the sphere.Comment: v2: 22 pages, 1 figure, references adde
The Detection Data Processing Mechanism for Vehicular Cyber Physical System in IoT Environment
With the development of the Internet of Things and big data technology, it was easy to collect personal situation information. The information collected in this way requires the user to support customized services via big data technology. However, traditional situational awareness systems request action through user cognition or provide consistent services for the specific purposes of multiple users. Therefore, this paper proposes a mechanism of Vehicular CPS with situational cognitive function that minimizes direct user intervention for user customization services. In this paper, we designed the system configuration and detailed process based on the scenario of the situation where the user is driving a car. A vector is used to provide a method for determining a dangerous water level by analyzing an abnormal state of a reception threshold with a sensor. The proposed system was analyzed by simulation. By using the authorization step that operates based on the sensor data, we were able to know that the reliability of the user is improved and that the reliable processing of the IoT service is possible. In the future, research for personal authentication and encryption is needed for more secure information processing
Generalization of Instanton-Induced Inflation and Dynamical Compactification
It was shown that Yang-Mills instantons on an internal space can trigger the
expansion of our four-dimensional universe as well as the dynamical
compactification of the internal space. We generalize the instanton-induced
inflation and dynamical compactification to general Einstein manifolds with
positive curvature and also to the FLRW metric with spatial curvature. We
explicitly construct Yang-Mills instantons on all Einstein manifolds under
consideration and find that the homogeneous and isotropic universe is allowed
only if the internal space is homogeneous. We then consider the FLRW metric
with spatial curvature as a solution of the eight-dimensional
Einstein-Yang-Mills theory. We find that open universe admits bouncing
solutions unlike the other cases .Comment: 30 pages, 5 figure
Oncostatin M stimulates cell migration and proliferation by down-regulating E-cadherin in HTR8/SVneo cell line through STAT3 activation
Remifentanil Prevents Withdrawal Movements Caused by Intravenous Injection of Rocuronium
PURPOSE: The incidence of pain induced withdrawal movement following intravenous injection of rocuronium is high. This randomized, double-blind, placebo-controlled study was designed to evaluate the effect of pretreatment of remifentanil on the withdrawal movements due to intravenous injection of rocuronium during anesthetic induction.
MATERIALS AND METHODS: Ninety adult female patients undergoing thyroidectomy were randomly allocated to three groups. Each patient intravenously received one of three solutions of equal volume (4 mL): normal saline (Group I, n=30), 0.5 microg/kg remifentanil (Group II, n=30) or 1 microg/kg remifentanil (Group III, n=30). Thirty seconds after remifentanil administration, anesthesia was induced with 5 mg/kg IV thiopental. Twenty seconds after thiopental injection, 0.6 mg/kg IV rocuronium was administered (injection rate of 0.5 mL/sec) and patients' withdrawal movements were assessed. Mean arterial pressure (MAP) and heart rate were assessed on arrival in the operation room, before the tracheal intubation and immediately, 1 and 2 min after the tracheal intubation.
RESULTS: The incidence of withdrawal movements was significantly lower in both of the remifentanil groups (3 and 0% in Group II and III, respectively) than in the saline group (70%). Remifentanil attenuated the increase of heart rate and MAP immediately and 1 min after the tracheal intubation.
CONCLUSION: The pretreatment with 0.5 and 1.0 microg/kg remifentanil of bolus doses prevented the withdrawal movements caused by rocuronium injection, and effectively blunted cardiovascular activation following tracheal intubationope
Strain-gradient-induced magnetic anisotropy in straight-stripe mixed-phase bismuth ferrites: An insight into flexomagnetic phenomenon
Implementation of antiferromagnetic compounds as active elements in
spintronics has been hindered by their insensitive nature against external
perturbations which causes difficulties in switching among different
antiferromagnetic spin configurations. Electrically-controllable strain
gradient can become a key parameter to tune the antiferromagnetic states of
multiferroic materials. We have discovered a correlation between an
electrically-written straight-stripe mixed-phase boundary and an in-plane
antiferromagnetic spin axis in highly-elongated La-5%-doped BiFeO thin
films by performing polarization-dependent photoemission electron microscopy in
conjunction with cluster model calculations. Model Hamiltonian calculation for
the single-ion anisotropy including the spin-orbit interaction has been
performed to figure out the physical origin of the link between the strain
gradient present in the mixed phase area and its antiferromagnetic spin axis.
Our findings enable estimation of the strain-gradient-induced magnetic
anisotropy energy per Fe ion at around 510 eV m, and provide a
new pathway towards an electric-field-induced 90 rotation of
antiferromagnetic spin axis at room temperature by flexomagnetism.Comment: 32 pages, 5 figure
Customersâ Continued Adoption of Mobile Apps and Their Satisfaction with Restaurants: The Case of McDonaldâs
Background: The major purpose of this research is to examine Contactless Technology (CT) usersâ post-adoption phenomena in the context of mobile apps (MA) run by a Quick Service Restaurant (QSR). It applies the Post-Adoption Model of Information System Continuance (PAMISC) to examine how QSR customersâ technology anxiety (TA), confirmation of initial expectations, perceived usefulness (PU), and satisfaction with CT relate to their continued intention of use. Furthermore, the study investigates the relationship between customersâ satisfaction with CT and their overall satisfaction with QSR.
Methods: To test the research model, we collected survey data from 245 users of MA provided by McDonaldâs restaurants in the US, which are analyzed through Partial Least Square analysis using SmartPLS 4.0.
Results: The theoretical relationships in the PAMISC hold true in the context of QSRâs MA. Current QSR customersâ TA is negatively associated with their perceived usefulness, but is not related to the degree of confirmation of using MA. Customersâ continued intention of use and satisfaction with MA are positively related to overall satisfaction with QSR.
Conclusion: Our study is among the first to provide empirical/practical evidence of the PAMISC in the context of IT-enabled hospitality services. It also extends the model in two important ways. First, the study examines the role of TA, an important personal trait relevant to individualsâ use of QSR technology. Second, it highlights customersâ satisfaction with firm-provided technology to improve their overall satisfaction with the firm in the context of QSRs. For practitioners, it is important for QSR managers to understand the impact of TA on customersâ adoption of MA, so that they can design their MA with simpler interfaces and more human aspects. Managers should also make sure that MA is well-designed to satisfy customersâ needs, which will then lead to those customersâ overall satisfaction with the QSR
Six-dimensional considerations of Einstein's connection for the first two classes. I. The recurrence relations in 6
Lower dimensional cases of Einstein's connection were already investigated by many authors for n=2,3,4,5. This paper is the first part of the following series of two papers, in which we obtain a surveyable tensorial representation of 6-dimensional Einstein's connection in terms of the unified field tensor, with main emphasis on the derivation of powerful and useful recurrence relations which hold in 6-dimensional Einstein's unified field theory (i.e., 6-g-UFT)
Bedside prediction of right subclavian venous catheter insertion length
AbstractBackground and objectiveThe present study aimed to evaluate whether right subclavian vein (SCV) catheter insertion depth can be predicted reliably by the distances from the SCV insertion site to the ipsilateral clavicular notch directly (denoted as I-IC), via the top of the SCV arch, or via the clavicle (denoted as I-T-IC and I-C-IC, respectively).MethodIn total, 70 SCV catheterizations were studied. The I-IC, I-T-IC, and I-C-IC distances in each case were measured after ultrasound-guided SCV catheter insertion. The actual length of the catheter between the insertion site and the ipsilateral clavicular notch, denoted as L, was calculated by using chest X-ray.ResultsL differed from the I-T-IC, I-C-IC, and I-IC distances by 0.14±0.53, 2.19±1.17, and â0.45±0.68cm, respectively. The mean I-T-IC distance was the most similar to the mean L (intraclass correlation coefficient=0.89). The mean I-IC was significantly shorter than L, while the mean I-C-IC was significantly longer. Linear regression analysis provided the following formula: Predicted SCV catheter insertion length (cm)=â0.037+0.036ĂHeight (cm)+0.903ĂI-T-IC (cm) (adjusted r2=0.64).ConclusionThe I-T-IC distance may be a reliable bedside predictor of the optimal insertion length for a right SCV cannulation
Tidal Effects on Intermediate Waters: A Case Study in the East/Japan Sea
Although tides are believed to be the most important source for diapycnal mixing in the ocean, few studies have directly simulated open-ocean circulation including tides. Because the East/Japan Sea (EJS) has been considered to be a âminiature ocean,â tidal effects on the intermediate water of the EJS are investigated by using an eddy-resolving ocean general circulation model that can take account of M2 and K1 tides as well as oceanic flows. The simulated temperature and salinity in the intermediate layer are significantly improved by including tides. The improvement results from the combined effect of two internal tides. The M2 internal tide, propagating into the interior of the EJS, enhances vertical mixing and brings watermass characteristics closer to those observed. The K1 internal tide, trapped along the coast, induces southwestward flow along the Russian coast in the upper layer and thereby enhances the so-called Liman Current, which transports fresh waters with density conducive to the ventilation of intermediate waters in the EJS
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