Joint Coverage Research Articles

Medicaid Coverage for Weight Loss Counseling May Make ‘Cents’

Medicaid Coverage for Weight Loss Counseling May Make ‘Cents’

Joint coverage and link utilization for fast IP local protection

To mitigate the impact of failures, many IP Fast Local Recovery (IPFLR) schemes have been proposed to reroute traffic in the events of failures. However, the existing IPFLR schemes either aimed to find the alternate backup routes to protect failures, or focused on balancing the traffic load routed on the backup routes. Furthermore, in Internet, flows are often managed by shortest path routing, and therefore purely determining the backup routing paths is not sufficient in protecting the error-prone networks. In this paper, we propose a Simulated Annealing based Load balancing and Protection (SALP) scheme to determine link weights for balancing link utilization in the non-failure state and simultaneously construct backup routing tables for protecting any single link failure in IP networks. In our proposed scheme, the two most significant issues, (1) load balancing and (2) coverage, are jointly considered to recover the network operation from single link failures. In the proposed scheme, upon a failure, only the nodes adjacent to a failure are activated to divert affected traffic to backup paths without disturbing regular traffic. Numerical results delineate that the proposed scheme achieves high coverage rate and load balancing at the expense of slightly increasing the entries of backup routing table.

Distributed Energy-Efficient Clustering algorithm for Wireless Sensor Networks

Wireless sensor networks (WSNs) consist of a large number of limited capability (power and processing) Micro Electro Mechanical Systems (MEMS) capable of measuring and reporting physical variables related to their environment. In surveillance applications, sensors are deployed in a certain field to detect and report events like presence, movement, or intrusion in the monitored area. Minimizing energy dissipation and maximizing network lifetime are important issues in the design of applications and protocols for sensor networks. Energy-efficient sensor state planning consists in finding an optimal assignment of states to sensors in order to maximize network lifetime. The existing scheme developed a centralized mechanism for near-optimal state assignment to sensors in large-scale cluster-based monitoring wireless sensor networks. The existing one was based on a tabu algorithm that computes a near-optimal network configuration in which each sensor can be activated, put in sleep mode or promoted as cluster head. The existing mechanism maximizes network lifetime while ensuring the full coverage of the monitored area and the connectivity of the obtained configuration. Connectivity is fulfilled through an optimally computed spanning tree connecting all the cluster heads. Due to abnormal node distribution in case of land surveillance, the existing tabu based optimal energy setting become complex. In addition the tabu algorithm keeps the probabilistic event detection independent for the respective node. To overcome the abnormal node Distribution event detection triviality, distributed energy efficient algorithm is proposed in this work. The proposed work of this thesis, develop a more sophisticated heuristic to improve the network lifetime. The proposed scheme handles distance-dependent probabilistic event detection. The distance based probability is a function of the distance of the corresponding sensor from the event. The proposed system develop distributed algorithm which addresses the energy-efficient clustering under the joint coverage and routing constraint. The experimental simulations are carried for the proposed model using Network Simulator 2 (NS-2) for multiple simulation times, routing topology and energy coverage area.

Simultaneous Confidence Bands for Nonlinear Regression Models with Application to Population Pharmacokinetic Analyses

Many applications in biostatistics rely on nonlinear regression models, such as, for example, population pharmacokinetic and pharmacodynamic modeling, or modeling approaches for dose-response characterization and dose selection. Such models are often expressed as nonlinear mixed-effects models, which are implemented in all major statistical software packages. Inference on the model curve can be based on the estimated parameters, from which pointwise confidence intervals for the mean profile at any single point in the covariate region (time, dose, etc.) can be derived. These pointwise confidence intervals, however, should not be used for simultaneous inferences beyond that single covariate value. If assessment over the entire covariate region is required, the joint coverage probability by using the combined pointwise confidence intervals is likely to be less than the nominal coverage probability. In this paper we consider simultaneous confidence bands for the mean profile over the covariate region of interest and propose two large-sample methods for their construction. The first method is based on the Schwarz inequality and an asymptotic χ 2 distribution. The second method relies on simulating from a multivariate normal distribution. We illustrate the methods with the pharmacokinetics of theophylline. In addition, we report the results of an extensive simulation study to investigate the operating characteristics of the two construction methods. Finally, we present extensions to construct simultaneous confidence bands for the difference of two models and to assess equivalence between two models in biosimilarity applications.

Joint ground and air emergency medical services coverage models: A greedy heuristic solution approach

Aeromedical and ground ambulance services often team up in responding to trauma crashes, especially when the emergency helicopter is unable to land at the crash scene. We propose location-coverage models and a greedy heuristic for their solution to simultaneously locate ground and air ambulances, and landing zones (transfer points). We provide a coverage definition based on both response time and total service time, and consider three coverage options; only ground emergency medical services (EMS) coverage, only air EMS coverage, or joint coverage of ground and air EMS in which the patient is transferred from an ambulance into an emergency helicopter at a transfer point. To analyze this complex coverage situation we develop two sets of models, which are variations of the Location Set Covering Problem (LSCP) and the Maximal Covering Location Problem (MCLP). These models address uncertainty in spatial distribution of motor vehicle crash locations by providing coverage to a given set of both crash nodes and paths. The models also consider unavailability of ground ambulances by drawing upon concepts from backup coverage models. We illustrate our results on a case study that uses crash data from the state of New Mexico. The case study shows that crash node and path coverage percentage values decrease when ground ambulances are utilized only within their own jurisdiction.

Adaptive cost efficient deployment strategy for homogeneous wireless camera sensors

Availability of low cost low power camera sensors is likely to make possible applications that may otherwise have been infeasible. In this paper we investigate a cost efficient camera sensor deployment strategy based on random deployment of homogeneous sensors to monitor and/or surveillance a region of interest. We assume that there are costs associated with the sensors as well as with the deployments and our goal is to minimize the total cost while satisfying the desired coverage requirement. We consider two cases which assume the sensing field is obstacle free or with obstacles, and we develop analytical methods to derive the expected coverage of a single sensor as well as the joint coverage for a given number of homogenous camera sensors. Following this we propose an adaptive sensor deployment strategy, which deploys different number of sensors in each iteration, based on our analytical method. We then evaluate the expected cost of our deployment strategy by deriving expressions for the number of deployments and the number of sensors deployed during each deployment as a function of the probability distributions of joint coverage by sensors. We carry out simulation studies to validate the analytical results. Simulation studies are also used to demonstrate that our deployment strategy leads to near optimal values of sensors and deployments and hence achieves the overall low cost.

Collaborative Event-Driven Coverage and Rate Allocation for Event Miss-Ratio Assurances in Wireless Sensor Networks

Wireless sensor networks are often required to provide event miss-ratio assurance for a given event type. To meet such assurances along with minimum energy consumption, this paper shows how a node's activation and rate assignment is dependent on its distance to event sources, and proposes a practical coverage and rate allocation (CORA) protocol to exploit this dependency in realistic environments. Both uniform event distribution and nonuniform event distribution are considered and the notion of ideal correlation distance around a clusterhead is introduced for on-duty node selection. In correlation distance guided CORA, rate assignment assists coverage scheduling by determining which nodes should be activated for minimizing data redundancy in transmission. Coverage scheduling assists rate assignment by controlling the amount of overlap among sensing regions of neighboring nodes, thereby providing sufficient data correlation for rate assignment. Extensive simulation results show that CORA meets the required event miss-ratios in realistic environments. CORA's joint coverage scheduling and rate allocation reduce the total energy expenditure by 85%, average battery energy consumption by 25%, and the overhead of source coding up to 90% as compared to existing rate allocation techniques.

Treatment of Painful Pediatric Flatfoot With Maxwell-Brancheau Subtalar Arthroereisis Implant A Retrospective Radiographic Review

The purposes of this study were to evaluate the outcome of pediatric patients who have undergone Maxwell-Brancheau arthroereisis (MBA) subtalar implants for the treatment of painful pediatric flatfoot deformities. In a retrospective study, 39 patients (68 feet) were evaluated clinically and radiographically. The mean age of the patients was 12 years (range, 6-16 years). The mean period of follow-up was 24 months (range, 6-61 months). Statistical evaluation was performed on all radiographic measurements. Additional surgical procedures (gastrocnemius recession, Achilles tendon lengthening, Kidner posterior tibial tendon advancement) were performed in 22 of 68 feet. There were 10 (15%) complications, which consisted of 10 reoperations in 10 feet. Implants were exchanged in 9 feet because of implant migration, undercorrection, and overcorrection. There was 1 reoperation (in 1 foot) for implant removal because of persistent sinus tarsi pain. Radiographic evaluation demonstrated an improvement of all parameters determined. The parameters that were evaluated include talonavicular joint coverage, as well as lateral and anterior-posterior talocalcaneal angles. There were significant changes noted in pre- and postoperative measurements (P < .001). The MBA implant is effective for the correction of painful, flexible flatfoot deformity in children in short-term follow-up. However, this is a multiplanar deformity, and additional procedures may be needed in addition to the MBA.

Triple pelvic osteotomy in the treatment of hip dysplasia

Insufficient femoral head coverage is found in a variety of diseases, with acetabular dysplasia as the most frequent disorder and triple pelvic osteotomy as the most recently introduced surgical treatment. This study analyses pre- and postoperative pathoanatomic characteristics of triple in comparison to Salter and Chiari osteotomies, with a logistic regression analysis of outcome predictor and effect explanator factors in relation to the chosen type of operation. The study involved 136 adolescents treated with Salter and Chiari osteotomies or a triple pelvic osteotomy at the Institute of Orthopaedic Surgery "Banjica" in Belgrade. The patients were between 10-20 years old at the time of operation. We collected and analyzed data from all the patients: illness history, operative parameters, preoperative and postoperative pathoanatomic data. The data was statistically processed using the statistical software SPSS, defining standard descriptive values, and by using the appropriate tests of analytic statistics: t-test for dependent and independent variables, chi2-test, Fisher's exact test, Wilcoxon's test, parameter correlation, one-way ANOVA, multi-factorial ANOVA and logistic regression, according to the type of the analyzed data and the conditions under which the statistical methods were applied. The average CE angle after triple pelvic osteotomy was 43.5 degrees, more improved than after the Salter osteotomy (33.0 degrees) and Chiari osteotomy (31.4 degrees) (F = 16.822; p < 0.01). Postoperative spherical congruence was also more frequent after the triple osteotomy than after the other two types of operations, and with a high significance. Preoperative painful discomfort was found to be a valid predictor of indications for the triple osteotomy over both Chiari and Salter osteotomies. The valid explanators of effect for the triple osteotomy are: postoperative joint congruence (compared to the Chiari osteotomy) and increase in joint coverage (compared to Salter osteotomy). Triple pelvic osteotomy is the method of choice in the management of acetabular dysplasia and other disturbances of hip joint containment in adolescent age.

Computed tomography study of radial head morphology

Computed tomography scans of 22 cadaveric adult elbows were obtained in 3 forearm positions: full supination, neutral, and full pronation. The radial head dimensions, the radiocapitellar joints, and the proximal radioulnar joints were measured. Multivariate analysis of variance was used to determine which portions of each articulation were the most congruent. The results showed that the radial head tended to become uncovered at the radial lip (P < .001). The radiocapitellar joint was tighter in pronation than in supination (P = .001). The proximal radioulnar joint was most congruent at the middle proximal radioulnar joint, at the midportion and posterior aspects rather than the anterior aspect (P < .001). The proximal radioulnar joint coverage was between 69 degrees and 79 degrees . Prosthesis trial sizing should be judged by the articulations providing the most congruency: (1) the ulnar lip or trough of the radiocapitellar joint in pronation and (2) the posterior or midportion of the middle proximal radioulnar joint.

Accuracy of T1 measurement with 3‐D Look‐Locker technique for dGEMRIC

To validate the accuracy of T1 measurement by three-dimensional Look-Locker method (3D LL) for delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) of human subjects with and without osteoarthritis (OA), as compared with two-dimensional inversion recovery fast spin-echo (2D IR-FSE) technique. MR sagittal images of the knees were acquired for T1 mapping in 29 subjects with standard 2D IR-FSE and 3D LL sequences 90-135 min following administration of 0.2 mmol/kg Gd-DTPA(2-). T1 maps of femoral and tibial cartilage were generated using custom software. Comparisons in T1 values between the two techniques were performed using regression analysis. Good agreement in T1 values between 2D IR-FSE and 3D LL was observed (R values of 0.90, and 0.85, and 0.86 for all, OA, and control subjects, respectively) when acquired within 15 min. The 3D LL sequence provides accurate T1 estimates of articular cartilage with advantages of entire joint coverage, shorter acquisition time, and a wide range of inversion times sampled within a single acquisition.

Three-Dimensional T1 Mapping for dGEMRIC at 3.0 T Using the Look Locker Method

The objective of this study was to implement a three-dimensional (3-D) T1 mapping sequence (3DLL) at 3.0 T for dGEMRIC based on the Look Locker scheme. Because all current reports on dGEMRIC are at 1.5 T and mostly using 2-D IR fast spin echo (FSE), data were acquired at 1.5 T and 3.0 T with both 3DLL and 2-D IR-FSE sequence. Phantoms with different concentrations of Gd(DTPA) were used and seven subjects (three asymptomatic, four symptomatic) were scanned using the dGEMRIC technique. The T1 measurements obtained on the phantom with 3DLL show very good agreement with those acquired with 2-D IR-FSE. Using a two-tailed paired t test, the T1 (Gd) measurements in two sections obtained in all subjects with both sequences were found to be statistically indistinguishable at either field strength (P = 0.07 at 1.5 T and P = 0.07 at 3.0 T). The preliminary data presented here suggest that the 3DLL sequence provides accurate T1 values with sufficient in-plane resolution and allows full joint coverage in less than 10 minutes.

Total Knee Arthroplasty Using Tissue Expander In Patient with Poor Soft Tissue Coverage of Knee: A Case Report

In total knee arthroplasty, the status of the soft tissue around the knee joint is important in preventing soft tissue complications and post-operative infection to obtain good results. This article reports a patient, who presented with a stiff knee joint and poor soft tissue coverage as a consequence of several operations after an open patellar fracture. The patient underwent total knee arthroplasty after an expansion of the skin and adjacent soft tissue using a tissue expander. The TKA results were satisfactory without any soft tissue complications including infections or skin necrosis.

SELECTING AND SHARPENING INFERENCES IN SIMULTANEOUS INFERENCE WITH A BAYESIAN APPROACH

A frequentist simultaneous confidence interval procedure requires the predetermination of the comparisons and their corresponding forms of confidence intervals before viewing the data in order that the error probability is controlled at a preassigned level. This often renders it less sensitive to detecting actual true differences and may result in it including many noninformative inferences. On the other hand, by taking a Bayesian approach, we can select the comparisons of interest and construct corresponding joint credible intervals after having viewed the data. This enables us to focus on those significant differences of interest and consequently to be able to make sharper inferences. The joint posterior probability of the credible intervals play a similar role as the joint coverage probability of the simultaneous confidence intervals, that is, to guarantee, with at least that probability, all the inferences made using the intervals are correct at the same time. In this article, we consider some standard problems in simultaneous inference and discuss how a Bayesian approach may be implemented. The methodologies are illustrated with examples.

An evaluation of municipal actions in the control of dengue vectors in the region of São José do Rio Prêto, São Paulo, 1989 to 1995

The aim of this study was to determine the coverage of municipal activities in terms of the control of Aedes aegypti and/or Aedes albopictus by routine house-to-house visits and by emergency activity, carried out between 1989 and 1995 in the area of São José do Rio Prêto, São Paulo State, and to evaluate the cross-correlation between them and the Breteau index (BI). For towns with up to 50,000 real estate properties, the joint coverage by routine and emergency activities was mostly appropriate and the routine activities showed a negative cross-correlation with the BI. For the county seat (more than 50,000 real estate properties), the coverage provided by the above activities was not correlated with the BI. In general, the coverage was inversely proportional to town size. Emergency activities did not show a correlation with the BI in any town size range, proving to be ineffective.

A technique for measuring the relative size and overlap of public Web search engines

Search engines are among the most useful and popular services on the Web. Users are eager to know how they compare. Which one has the largest coverage? Have they indexed the same portion of the Web? How many pages are out there? Although these questions have been debated in the popular and technical press, no objective evaluation methodology has been proposed and few clear answers have emerged. In this paper we describe a standardized, statistical way of measuring search engine coverage and overlap through random queries. Our technique does not require privileged access to any database. It can be implemented by third-party evaluators using only public query interfaces. We present results from our experiments showing size and overlap estimates for HotBot, AltaVista, Excite, and Infoseek as percentages of their total joint coverage in mid 1997 and in November 1997. Our method does not provide absolute values. However using data from other sources we estimate that as of November 1997 the number of pages indexed by HotBot, AltaVista, Excite, and Infoseek were respectively roughly 77M, 100M, 32M, and 17M and the joint total coverage was 160 million pages. We further conjecture that the size of the static, public Web as of November was over 200 million pages. The most startling finding is that the overlap is very small: less than 1.4% of the total coverage, or about 2.2 million pages were indexed by all four engines.

Three-dimensional computer analysis of complex acetabular insufficiency.

Fourteen patients with acetabular dysplasia were studied by using three-dimensional computed tomography (CT) reconstructions before pelvic osteotomies. Computer manipulation of the data allowed a preoperative visual assessment of acetabular shape, assessment of potential congruency between the femoral head and acetabulum by using a mathematical best-fit sphere, and measurement of surface contact distances that depict joint coverage and relate to concentration of weight-bearing forces. Preoperative evaluation of the three-dimensional images for these 14 patients allowed improved understanding of their abnormal anatomy and better surgical planning.