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Medicaid reimbursements for physician services are determined by each state. However, how these reimbursements vary between states, and how these reimbursements vary in comparison to Medicare reimbursements is unknown for musculoskeletal radiology studies.To evaluate the variability in Medicaid and Medicare physician reimbursements for musculoskeletal imaging studies between states.We evaluated the Medicare and Medicaid physician reimbursements for the most commonly performed musculoskeletal radiology studies (15 radiographs and 10 MRIs) based on Medicare's 2017 National Summary Data File. Medicare and Medicaid reimbursements for these studies were compared by dollar difference (difference in reimbursement in dollars between Medicare and Medicaid). State-wide variability in these reimbursements was quantified by the coefficient of variation (COV) and by the dollar difference in reimbursement amounts. Medicaid and Medicare reimbursement rates were compared using a paired t-test, since the data was paired by state.The mean Medicaid reimbursement rates were lower for musculoskeletal radiographs (p 0.05) but higher for musculoskeletal MRI studies than the Medicare rates (p 0.05). As hypothesized, there was variation in both Medicare and Medicaid imaging reimbursements between states, however, the variation was substantially higher for Medicaid reimbursements. We found the Medicare reimbursement COV between states was 0.07 for all imaging studies, whereas the Medicaid reimbursement COV between states varied from 0.23 to 0.55 for radiographs and from 0.31 to 0.45 for MRIs.The data show that there is mild, but constant variation across imaging studies in Medicare reimbursement for musculoskeletal imaging studies between states. However, there is more variation in the Medicaid reimbursements across imaging studies and between states. More appropriate reimbursement may increase access to care for Medicaid patients.

In the present work, the formulation and solution of the inverse problem of structural damage identification is presented based on the Bayesian inference, a powerful approach that has been widely used for the formulation of inverse problems in a statistical framework. The structural damage is continuously described by a cohesion field, which is spatially discretized by the finite element method, and the solution of the inverse problem of damage identification, from the Bayesian point of view, is the posterior probability densities of the nodal cohesion parameters. In this approach, prior information about the parameters of interest and the quantification of the uncertainties related to the magnitudes measured can be used to estimate the sought parameters. Markov Chain Monte Carlo (MCMC) method, implemented via the Metropolis-Hastings (MH) algorithm, is commonly used to sample such densities. However, the conventional MH algorithm may present some difficulties, for instance, in high dimensional problems or when the parameters of interest are highly correlated or the posterior probability density is very peaked. In order to overcome these difficulties, a new adaptive MH algorithm (P-AMH) is proposed in the present work. Numerical results related to an inverse problem of damage identification in a simply supported Euler-Bernoulli beam are presented. Synthetic experimental time domain data, obtained with different damage scenarios, and noise levels, were addressed with the aim at assessing the proposed damage identification approach. An adaptive MH algorithm (H-AMH) and the conventional MH algorithm, already consolidated in the literature, were also considered for comparison purposes. The numerical results show that both adaptive algorithms outperformed the conventional MH. Besides, the P-AMH provided Markov chains with faster convergence and better mixing than the ones provided by the H-AMH.

Since neuronal activity is coupled with neurovascular activity, we aimed to analyze the cerebral blood flow hemodynamics during and following high-definition transcranial direct current stimulation (HD-tDCS). We assessed the mean middle cerebral artery blood flow velocity (MCA-BFv) bilaterally using transcranial doppler ultrasound, during and after HD-tDCS, in eleven right-handed healthy adult participants (6 women, 5 men; mean age 31 ± 5.6 years old), with no evidence of brain or cardiovascular dysfunction. The HD-tDCS electrode montage was centered over the right temporo-parietal junction. The stimulation protocol comprised 3 blocks of 2 min at each current intensity (1, 2, and 3 mA) and an inter-stimulus interval of 5 min between blocks. Participants received three electrical stimulation conditions (anode center, cathode center, and sham) on three different days, with an interval of at least 24 h. Stimulation was well tolerated across HD-tDCS conditions tested, and the volunteers reported no significant discomfort related to stimulation. There was no significant difference in the right or the left MCA-BFv during or after the stimulation protocol across all stimulation conditions. We conclude that at a range of intensities, vascular reaction assessed using middle cerebral artery blood flow is not significantly altered during or after HD-tDCS both locally and remotely, which provides further evidence for the safety of HD-tDCS.

Droop control is used for power management in DC grids. Based on the level of the DC grid voltage, the amount of power regulated to or from the appliance is regulated such, that power management is possible. The Universal 4 Leg is a laboratory setup for studying the functionality of a grid manager for power management. It has four independent outputs that can be regulated with pulse width modulation to control the power flow between the DC grid and for example, a rechargeable battery, solar panel or any passive load like lighting or heating

Background This study examined the immediate outcomes during the perioperative period associated with drains in the setting of total shoulder arthroplasty or reverse shoulder arthroplasty. We hypothesized that drain use would result in lower postoperative hemoglobin and hematocrit levels that would increase transfusion rates and longer hospital stays that would increase hospital costs. Methods The study prospectively randomized 100 patients (55% women; average age, 69.3 years) who underwent total shoulder arthroplasty or reverse shoulder arthroplasty to receive a closed-suction drainage device (drain group, n = 50) or not (control group, n = 50) at the time of wound closure. Basic demographic information and intraoperative and postoperative data were collected. Results The groups were similar with respect to basic patient demographics. Postoperatively, drains had no effect on transfusion rates or any perioperative complication (P > .715). There were also no significant differences in hemoglobin or hematocrit levels immediately after surgery or on postoperative day 1. On average, patients were discharged from the hospital 1.6 days and 2.1 days postoperatively in the control and drain groups, respectively (P = .124). The average cost associated for the control cohort's hospital stay was $35,796 ± $13,078 compared with $43,219 ± $24,679 for the drain cohort (P = .063). Discussion Drain use after shoulder arthroplasty had no appreciable difference on short-term perioperative outcomes, postoperative anemia, length of hospital stay, or cost. It is possible that the potential negative effects of postoperative drainage are blunted by the routine use of tranexamic acid.

The present work is concerned with the inverse problem of structural damage identification. The damage state of the structure is continuously described by a cohesion field, spatially discretized by the finite element method, and a response surface model (RSM) is considered to provide a polynomial relation between the nodal cohesion parameters and elements of the flexibility matrix of the system. Here, the inverse problem of damage identification is posed as an optimization one, where the objective is to minimize, with respect to the nodal cohesion parameters, the squared norm of the difference between an experimental response vector, composed with elements of the flexibility matrix obtained from a modal test on the supposed damaged structure, and the corresponding one predicted by a RSM. The Particle Swarm Optimization method was considered for solving the resulting inverse problem of damage identification. A simply supported Euler-Bernoulli beam, with three different damage scenarios and the synthetic experimental mode shapes corrupted with two different levels of noise, was considered in the numerical assessment of the proposed damage identification approach. The numerical results show that the proposed approach, built on a RSM of the flexibility matrix, presented results comparable with those obtained with the approach built on the FEM of the structure and it also presented an extremely higher computational performance.

In order to reduce the energy cost while improving the process operation, a study which aims to analyze the influence of the operational parameters variations and determine the optimal operating conditions of a pilot multi-effect desalination system (MED) at CIEMAT-Plataforma Solar de Almeriia (PSA) has been performed. An equation-based object-oriented mathematical model of the experimental MED plant, implemented using the modeling language Modelica and previously developed, calibrated and validated, has been adapted to carry out this study. Firstly, an energetic and exergetic analysis of the process under nominal conditions has been carried out, revealing the key sources of energy and exergy consumption. On the one hand, the thermal energy contained in the mass outflows are the main responsible source of the high energy consumption, on the other hand the entropy generation and the heat exchanged with the environment are the responsible of the exergy degradation. Secondly, a study on the influence of the operational parameters shows that the production of the real plant under nominal conditions is far from the maximum simulated values and some operational parameters have not a great influence in the process with respect to the rest. Finally, using a genetic optimization algorithm implemented in the modeling tool, a optimization process taking into account different energy and exergy performance criteria, sets optimal operational set points.

Electricity market decarbonization using renewable energies is essential to significantly reduce greenhouse gas emissions. However, the identification of the optimum electrical mix for each country is a challenging and complex task because of the many boundary conditions that must be taken into account, thus demanding the use of advanced analysis and computing tools. This paper presents a methodology based on artificial intelligence developed for this purpose and the results obtained when applied to the specific case of the Spanish electricity market long-term decarbonization. It also shows how effective this methodology is to find the optimum electrical mix fulfilling previously defined objectives: 100% coverage of the demand while simultaneously minimizing the electricity cost and curtailments. Results show the significant barriers to achieve a 100% renewable electrical mix without excessive curtailments or installed power. The methodology described here is suitable for any other country and target objectives.

This work addresses the experimental validation of the explicit estimation of timewise varying boundary heat fluxes in thermally thin plates employing temperature measurements obtained by infrared thermography. The measurements were regularized with the controlled truncation of the eigenfunction expansions that are employed to overcome the ill-posed nature of the inverse problem. In order to allow for a critical analysis of the obtained estimates, reference results were obtained from Bayesian inference, implemented with the Markov Chain Monte Carlo (MCMC) method and the total variation prior. The good results achieved with the explicit technique, with very little computational effort, demonstrate the feasibility of the developed approach for practical applications.

Submitted by Jairo Amaro (jairo.amaro@sibi.ufrj.br) on 2019-06-06T16:25:31Z No. of bitstreams: 1 4-2017_Conjugated-heat-transfer-in-circular-microchannels-min.pdf: 430370 bytes, checksum: 00dd0e4c7f56fdb8b385ed86a2010a8c (MD5) Made available in DSpace on 2019-06-06T16:25:31Z (GMT). No. of bitstreams: 1 4-2017_Conjugated-heat-transfer-in-circular-microchannels-min.pdf: 430370 bytes, checksum: 00dd0e4c7f56fdb8b385ed86a2010a8c (MD5) Previous issue date: 2018-02-06 Indisponível. An integral transforms analysis is undertaken for conjugated heat transfer in circular microchannels with laminar gaseous flow in the slip flow regime. The solution methodology is based on the Generalized Integral Transform Technique applied to a single domain formulation that models the coupled heat transfer phenomena at the fluid stream and at the channel wall. The single domain formulation results in just one partial differential equation for the energy balance, making use of spatially variable coefficients with abrupt transitions, and accounting for the temperature jump at the interface due to the Knudsen numbers within the slip flow regime. This work extends the single domain formulation strategy, not a priori applicable to problems with discontinuities, by considering a very thin fictitious layer at the fluid-wall interface region, so as to mathematically represent an equivalence to the temperature jump. An integral balance technique for enhancing the convergence of the eigenfunctions is employed, so as to achieve more accurate results and improve convergence for the so derived multiscale problem. The results obtained are critically compared against a dedicated finite difference numerical solution for the original multi-region problem. Results for the Nusselt number are presented in order to investigate its behavior with respect to different Péclet and Knudsen numbers, and different wall thicknesses values, confirming the importance of the combined effects of slip flow, axial conduction and heat transfer conjugation in the analysis.

Internal combustion engine is the most spread motor machine in the world. The present work shows an alternative perspective to the study of the work cycle of combustion engines. This is not obtained by direct measurement, but is built with the data obtained in two experimental tests. In the first, pressure variations without combustion are measured in one cylinder of the engine, while the engine is fully loaded with the remaining cylinders. Then, during a traditional brake power test, the combustion products are measured to obtain the data corresponding to the combustion and expansion phase by calculation, applying the model of the indicated cycle provided to the same number of rotations as in the first test. As an application of the principle of overlapping effects, the result is obtaining the indicated cycle of the machine that serves to evaluate its efficiency. At the same time, the actual working fluid and the particular system are characterized. The text that is presented below focuses on the experimental validation of the described trials, presenting the methodology followed from the metrological and statistical point of view. It is expected that the results of the application of the model of the indicated cycle will provide data to characterize alternative hybrid fuels to be used in existing engines.

In Multi-Effect Distillation with Thermal Vapor Compression (MED-TVC) plants, fixed steam ejectors are usually designed for constant motive steam pressures. When these distillation units are integrated into Concentrating Solar Power (CSP) plants, the available motive steam pressure is normally lower than the design value (due to the partial load operation of the power cycle under different solar radiation conditions), being the efficiency of the steam ejectors drastically reduced. Also, it has a negative impact on the fresh water production from the desalination plant because of a decrease in the mass flow of the motive steam. All this can be avoided by using variable nozzle steam ejectors, which can adjust the mass flow rate of steam according to the variable pressure so that they are always operating with the maximum efficiency and therefore they can maintain the freshwater production of the desalination plant near to the nominal value. This work presents a study of the coupling between CSP plants and MED-TVC units using variable nozzle steam ejectors in a wide range of operating conditions (on and off-design). For this purpose, simulations of a Rankine cycle power block in a typical commercial CSP plant have been firstly performed at different thermal loads to investigate the operational limits that allow keeping the motive steam mass flow rates constant. Then, the efficiency and fresh water production of an MED-TVC unit coupled to the different extractions available at the CSP plant have been studied in a wide range of operating conditions, covering both nominal and partial loads. To this end, an operational model of the MED-TVC unit has been developed based on a design model previously published by the authors.