2,926 research outputs found
Streaming in-patient BPM data to the cloud with a real-time monitoring system
Monitoring the heart activities for old people or people with medical history (Arrhythmia or CHD) is targeted by most new medical technologies. This paper demonstrated an in-patient real-time monitoring system for heart rate estimation. A ratio of beats per minute (BPM) is continuously recorded, streamed and archived to the cloud via WeMos WiFi development board. This cost effective system is simply based on two sub-systems: BPM data acquisition through pulse sensor and WeMos-based communication systems. The streamed BPM data are saved instantaneously in Google drive as spreadsheets which can only be accessed by authorized persons wherever the internet service is available. Thus, the person in charge can remotely observe the patientâs status and do analytics for the archived data. A pilot study with eight subjects was carried out to validate the developed BPM tele-monitoring system. Encouraging results have been achieved
Locking-free two-layer Timoshenko beam element with interlayer slip
A new locking-free strain-based finite element formulation for the numerical treatment of linear static analysis of two-layer planar composite beams with interlayer slip is proposed. In this formulation, the modified principle of virtual work is introduced as a basis for the finite element discretization. The linear kinematic equations are included into the principle by the procedure, similar to that of Lagrangian multipliers. A strain field vector remains the only unknown function to be interpolated in the finite element implementation of the principle. In contrast with some of the displacement-based and mixed finite element formulations of the composite beams with interlayer slip, the present formulation is completely locking-free. Hence, there are no shear and slip locking, poor convergence and stress oscillations in these finite elements. The generalization of the composite beam theory with the consideration of the Timoshenko beam theory for the individual component of a composite beam represents a substantial contribution in the field of analysis of non-slender composite beams with an interlayer slip. An extension of the present formulation to the non-linear material problems is straightforward. As only a few finite elements are needed to describe a composite beam with great precision, the new finite element formulations is perfectly suited for practical calculations. (c) 2007 Elsevier B.V. All rights reserved
A triangulated perspective for understanding CAM use in Lebanon: a qualitative study.
Background: Existing evidence marked a prevalent use of Complementary and Alternative Medicine (CAM) therapies in Lebanon that is concomitant with low rates of disclosure to health care providers and limited knowledge among the general public of safety and side effects of CAM use.
Objectives: To examine the perspectives of Lebanese CAM users, CAM providers, and health care providers (HCPs) regarding their understanding of CAM and of the Push and Pull factors that drive its use.
Methods: A qualitative research study was conducted using in-depth interviews, targeting Lebanese adults (CAM users; 18-65 years) (n=14), CAM providers such as yoga instructors, owners of CAM product outlets, herbalists, and religious figures (n=13); and HCPs including physicians, nurses, dietitians, and pharmacists (n=14). The topic guide covered, in addition to the understanding of CAM, the Push and Pull factors driving CAM use. The adults were recruited by convenient sampling, and CAM providers and HCPs using a purposive sampling approach. Interviews were audiotaped, transcribed, and translated into English. Analysis was performed using a qualitative thematic approach. Similarities and differences in the perceptions of the participants with regards to factors that influence CAM use were charted and contrasted, using a triangulated approach.
Results: The three study groups exhibited a similar understanding of CAM, referring to non-conventional therapies used to prevent/treat diseases or to enhance wellbeing. CAM users and CAM providers identified "distrust in HCPs", "lack of patient-centered care in CM", and "limitations and side effects of CM" as important Push factors. All study groups highlighted the limited CAM knowledge of HCPs as a main reason for the lack of patient-centered care. All three groups also underscored the affordability and the social and cultural support for CAM as main enablers of its prevalent use. Unlike HCPs who were skeptical about the safety and effectiveness of CAM, CAM users and CAM providers indicated that most of CAM therapies are safe and efficient.
Conclusions: The triangulation of perspectives (CAM users, CAM providers, and HCPs) in this study allowed a comprehensive appraisal of CAM use and its drivers. Improving the HCPs' CAM-related knowledge, promoting patient-centered care and fostering an open dialogue between HCPs and CAM providers are among the recommendations of the study.
Background: Existing evidence marked a prevalent use of Complementary and Alternative Medicine (CAM) therapies in Lebanon that is concomitant with low rates of disclosure to health care providers and limited knowledge among the general public of safety and side effects of CAM use.
Objectives: To examine the perspectives of Lebanese CAM users, CAM providers, and health care providers (HCPs) regarding their understanding of CAM and of the Push and Pull factors that drive its use.
Methods: A qualitative research study was conducted using in-depth interviews, targeting Lebanese adults (CAM users; 18-65 years) (n=14), CAM providers such as yoga instructors, owners of CAM product outlets, herbalists, and religious figures (n=13); and HCPs including physicians, nurses, dietitians, and pharmacists (n=14). The topic guide covered, in addition to the understanding of CAM, the Push and Pull factors driving CAM use. The adults were recruited by convenient sampling, and CAM providers and HCPs using a purposive sampling approach. Interviews were audiotaped, transcribed, and translated into English. Analysis was performed using a qualitative thematic approach. Similarities and differences in the perceptions of the participants with regards to factors that influence CAM use were charted and contrasted, using a triangulated approach.
Results: The three study groups exhibited a similar understanding of CAM, referring to non-conventional therapies used to prevent/treat diseases or to enhance wellbeing. CAM users and CAM providers identified "distrust in HCPs", "lack of patient-centered care in CM", and "limitations and side effects of CM" as important Push factors. All study groups highlighted the limited CAM knowledge of HCPs as a main reason for the lack of patient-centered care. All three groups also underscored the affordability and the social and cultural support for CAM as main enablers of its prevalent use. Unlike HCPs who were skeptical about the safety and effectiveness of CAM, CAM users and CAM providers indicated that most of CAM therapies are safe and efficient.
Conclusions: The triangulation of perspectives (CAM users, CAM providers, and HCPs) in this study allowed a comprehensive appraisal of CAM use and its drivers. Improving the HCPs' CAM-related knowledge, promoting patient-centered care and fostering an open dialogue between HCPs and CAM providers are among the recommendations of the study
Determination of the Loading Mode Dependence of the Proportionality Parameter for the Tearing Energy of Embedded Flaws in Elastomers Under Multiaxial Deformations
In this paper, the relationship between the tearing energy and the far-field cracking energy density (CED) is evaluated for an embedded penny-shaped flaw in a 3D elastomer body under a range of loading modes. A 3D finite element model of the system is used to develop a computational-based fracture mechanics approach which is used to evaluate the tearing energy at the crack in different multiaxial loading states. By analysing the tearing energyâs relationship to the far-field CED, the proportionality parameter in the CED formulation is found to be a function of stretch and biaxiality. Using a definition of biaxiality that gives a unique value for each loading mode, the proportionality parameter becomes a linear function of stretch and biaxiality. Tearing energies predicted through the resulting equation show excellent agreement to those calculated computationally
Formulation and Permeation Kinetic Studies of Flurbiprofen Gel
Purpose: To investigate the in vitro permeation and drug release kinetics of flurbiprofen gel.Methods: Thirteen batches (G1, G2 ⊠G13) of flurbiprofen gels were prepared using different ratios ofpermeation enhancers, i.e., propylene glycol (PG) and polyethylene glycol (PEG), by response surface methodology (RSM). Viscosity, pH, spreadability, consistency and drug content of the flurbiprofen gels were measured. Permeation experiments were conducted using silicone membrane in a modified Franz diffusion cell. Permeation parameters determined include diffusion coefficient (D), Flux (J), lag time (tLag), permeation coefficient (Kp), input rate (IR) and enhancement ratio (ER). Primary skin irritation test was performed for the optimized gel, G3, using 11 human volunteers.Results: Maximum solubility (72.15 ± 0.02 mg/mL) of flurbiprofen was observed in a mixture (2:1) of methanol and water. Partition coefficient (Ko/w) was determined as logP = 3.68 ± 0.11. The gels were stable under various storage conditions, and were homogenous, crystalline and transparent. Viscosity, pH, spreadability, consistency and drug content were in the range of 150 â 178 Ă 102 cps, 5.42 - 5.75, 5.0 - 7.0 g.cm/s, 3.0 - 9.0 mm, and 97.99 - 99.86 %, respectively. No irritation or lesions (erythma, redness and ulceration) occurred in human volunteers over a 30-day period. The optimized formulation, G3, showed maximum flux through silicone membrane.Conclusion: PG and PEG are effective enhancers of flurbiprofen from various formulations when used in various ratios.Keywords: Flurbiprofen, Gel, Diffusion, Permeation enhancers, Skin irritation, Silicone membran
Exact slip-buckling analysis of two-layer composite columns
A mathematical model for slip-buckling has been proposed and its analytical solution has been found for the analysis of layered and geometrically perfect composite columns with inter-layer slip between the layers. The analytical study has been carried out to evaluate exact critical forces and to compare them to those in the literature. Particular emphasis has been placed on the influence of interface compliance on decreasing the bifurcation loads. For this purpose, a preliminary parametric study has been performed by which the influence of various material and geometric parameters on buckling forces have been investigated. (C) 2009 Elsevier Ltd. All rights reserved
Fire analysis of timber composite beams with interlayer slip
The purpose of this paper is to model the behaviour of timber composite beams with interlayer slip, when simultaneously exposed to static loading and fire. A transient moisture-thermal state of a timber beam is analysed by the Luikov equations, and mechanical behaviour of timber composite beam is modelled by Reissner's kinematic equations. The model can handle layers of different materials. Material properties are functions of temperature. The thermal model is validated against the experimental data presented in the literature. Generally, the model provides excellent agreement with the experimental data. It is shown that the material properties of timber play an important role in the fire resistance analysis of timber structures when exposed to fire
The 2013 M_w 7.7 Balochistan Earthquake: Seismic Potential of an Accretionary Wedge
Great earthquakes rarely occur within active accretionary prisms, despite the intense longâterm deformation associated with the formation of these geologic structures. This paucity of earthquakes is often attributed to partitioning of deformation across multiple structures as well as aseismic deformation within and at the base of the prism (Davis et al., 1983). We use teleseismic data and satellite optical and radar imaging of the 2013 M_w 7.7 earthquake that occurred on the southeastern edge of the Makran plate boundary zone to study this unexpected earthquake. We first compute a multiple pointâsource solution from Wâphase waveforms to estimate fault geometry and rupture duration and timing. We then derive the distribution of subsurface fault slip from geodetic coseismic offsets. We sample for the slip posterior probability density function using a Bayesian approach, including a full description of the data covariance and accounting for errors in the elastic structure of the crust. The rupture nucleated on a subvertical segment, branching out of the Chaman fault system, and grew into a major earthquake along a 50° northâdipping thrust fault with significant alongâstrike curvature. Fault slip propagated at an average speed of 3.0ââkm/s for about 180 km and is concentrated in the top 10 km with no displacement on the underlying dĂ©collement. This earthquake does not exhibit significant slip deficit near the surface, nor is there significant segmentation of the rupture. We propose that complex interaction between the subduction accommodating the ArabiaâEurasia convergence to the south and the Ornach Nal fault plate boundary between India and Eurasia resulted in the significant strain gradient observed prior to this earthquake. Convergence in this region is accommodated both along the subduction megathrust and as internal deformation of the accretionary wedge
Compositional Variations in Sands of the Bagnold Dunes, Gale Crater, Mars, from Visible-Shortwave Infrared Spectroscopy and Comparison to Ground-Truth from the Curiosity Rover
During its ascent up Mount Sharp, the Mars Science Laboratory Curiosity rover traversed the Bagnold Dune Field. We model sand modal mineralogy and grain size at four locations near the rover traverse, using orbital shortwave infrared single-scattering albedo spectra and a Markov chain Monte Carlo implementation of Hapke's radiative transfer theory to fully constrain uncertainties and permitted solutions. These predictions, evaluated against in situ measurements at one site from the Curiosity rover, show that X-ray diffraction-measured mineralogy of the basaltic sands is within the 95% confidence interval of model predictions. However, predictions are relatively insensitive to grain size and are nonunique, especially when modeling the composition of minerals with solid solutions. We find an overall basaltic mineralogy and show subtle spatial variations in composition in and around the Bagnold Dunes, consistent with a mafic enrichment of sands with cumulative aeolian-transport distance by sorting of olivine, pyroxene, and plagioclase grains. Furthermore, the large variations in Fe and Mg abundances (~20 wt %) at the Bagnold Dunes suggest that compositional variability may be enhanced by local mixing of well-sorted sand with proximal sand sources. Our estimates demonstrate a method for orbital quantification of composition with rigorous uncertainty determination and provide key constraints for interpreting in situ measurements of compositional variability within Martian aeolian sandstones
Evaluation of seismic demand for substandard reinforced concrete structures
Background: Reinforced Concrete (RC) buildings with no seismic design exhibit degrading behaviour under severe seismic loading due to non-ductile brittle failure modes. The seismic performance of such substandard structures can be predicted using existing capacity demand diagram methods through the idealization of the non-linear capacity curve of the degrading system, and its comparison with a reduced earthquake demand spectrum. Objective: Modern non-linear static methods for derivation of capacity curves incorporate idealization assumptions that are too simplistic and do not apply for sub-standard buildings. The conventional idealisation procedures cannot maintain the true strength degradation behaviour of such structures in the post-peak part, and thus may lead to significant errors in seismic performance prediction especially in the cases of brittle failure modes dominating the response. Method: In order to increase the accuracy of the prediction, an alternative idealisation procedure using equivalent elastic perfectly plastic systems is proposed herein that can be used in conjunction with any capacity demand diagram method. Results: Moreover, the performance of this improved equivalent linearization procedure in predicting the response of an RC frame is assessed herein. Conclusion: This improved idealization procedure has been proven to reduce the error in the seismic performance prediction as compared to seismic shaking table test results [1] and will be further investigated probabilistically herein
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