First-principles periodic calculation of four-body spin terms in high-Tc cuprate superconductors

A general mapping between the energy of pertinent magnetic solutions and the diagonal terms of the spin Hamiltonian in a local representation provides the first general framework to extract accurate values for the many body terms of extended spin Hamiltonians from periodic first-principle calculations. Estimates of these terms for La2CuO4, the paradigm of high-Tc superconductor parent compounds, and for the SrCu2O3 ladder compound are reported. For La2CuO4, present results support experimental evidence by Toader et al. [Phys. Rev. Lett. 94, 197202 (2005)]. For SrCu2O3 even larger four-body spin amplitudes are found together with Jl/Jr=1 and non-negligible ferromagnetic interladder exchange.

First-principles periodic calculation of four-body spin terms in high-Tc Cuprate superconductors

A general mapping between the energy of pertinent magnetic solutions and the diagonal terms of the spin Hamiltonian in a local representation provides the first general framework to extract accurate values for the many body terms of extended spin Hamiltonians from periodic first-principle calculations. Estimates of these terms for La2CuO4, the paradigm of high-Tc superconductor parent compounds, and for the SrCu2O3 ladder compound are reported. For La2CuO4, present results support experimental evidence by Toader et al. [Phys. Rev. Lett. 94, 197202 (2005)]. For SrCu2O3 even larger four-body spin amplitudes are found together with Jl/Jr=1 and non-negligible ferromagnetic interladder exchange.

Benchmarking therapeutic drug monitoring software: A systematic evaluation of available computer tools

Introduction: Therapeutic drug monitoring (TDM) aims at optimizing treatment by individualizing dosage regimen based on measurement of blood concentrations. Maintaining concentrations within a target range requires pharmacokinetic and clinical capabilities. Bayesian calculation represents a gold standard in TDM approach but requires computing assistance. In the last decades computer programs have been developed to assist clinicians in this assignment. The aim of this benchmarking was to assess and compare computer tools designed to support TDM clinical activities.¦Method: Literature and Internet search was performed to identify software. All programs were tested on common personal computer. Each program was scored against a standardized grid covering pharmacokinetic relevance, user-friendliness, computing aspects, interfacing, and storage. A weighting factor was applied to each criterion of the grid to consider its relative importance. To assess the robustness of the software, six representative clinical vignettes were also processed through all of them.¦Results: 12 software tools were identified, tested and ranked. It represents a comprehensive review of the available software's characteristics. Numbers of drugs handled vary widely and 8 programs offer the ability to the user to add its own drug model. 10 computer programs are able to compute Bayesian dosage adaptation based on a blood concentration (a posteriori adjustment) while 9 are also able to suggest a priori dosage regimen (prior to any blood concentration measurement), based on individual patient covariates, such as age, gender, weight. Among those applying Bayesian analysis, one uses the non-parametric approach. The top 2 software emerging from this benchmark are MwPharm and TCIWorks. Other programs evaluated have also a good potential but are less sophisticated (e.g. in terms of storage or report generation) or less user-friendly.¦Conclusion: Whereas 2 integrated programs are at the top of the ranked listed, such complex tools would possibly not fit all institutions, and each software tool must be regarded with respect to individual needs of hospitals or clinicians. Interest in computing tool to support therapeutic monitoring is still growing. Although developers put efforts into it the last years, there is still room for improvement, especially in terms of institutional information system interfacing, user-friendliness, capacity of data storage and report generation.

Kinetic resolution: a powerful tool for the synthesis of planar-chiral ferrocenes

Since the serendipitous discovery of ferrocene by Pauson and Kealy in 1951, it has become one of the most important structures in Organic Chemistry. Lately, kinetic resolution has emerged as a useful tool for the synthesis of planar chiral ferrocenes. This review aims to cover and discuss the development of this topic.

Auditing the management of vaccine-preventable disease outbreaks: the need for a tool

Public health activities, especially infectious disease control, depend on effective teamwork. We present the results of a pilot audit questionnaire aimed at assessing the quality of public health services in the management of VPD outbreaks. Audit questionnaire with three main areas indicators (structure, process and results) was developed. Guidelines were set and each indicator was assessed by three auditors. Differences in indicator scores according to median size of outbreaks were determined by ANOVA (significance at p (greater than or equal to) 0.05). Of 154 outbreaks; eighteen indicators had a satisfactory mean score, indicator "updated guidelines" and "timely reporting" had a poor mean score (2.84±106 and 2.44±1.67, respectively). Statistically significant differences were found according to outbreak size, in the indicators "availability of guidelines/protocol updated less than 3 years ago" (p = 0.03) and "days needed for outbreak control" (p = 0.04). Improving availability of updated guidelines, enhancing timely reporting and adequate recording of control procedures taken is needed to allow for management assessment and improvement.

Phytolith and spherulite studies of herbivores dung from the African Savannah as a tool for palaeocological reconstruction.

Los restos fecales están compuestos mayoritariamente por materia orgánica, la cual se degrada con el tiempo despareciendo finalmente del registro arqueológico. Sin embargo, estos restos fecales también contienen ciertos elementos resistentes al paso del tiempo y a los efectos postdeposicionales. Las esferulitas son cristales de carbonato cálcico formadas en los intestinos de ciertos animales herbívoros, principalmente rumiantes y que posteriormente son depositados en los restos fecales. Los fitolitos de sílice, aunque se forman en las plantas, son también comúnmente identificados en los restos fecales de animales herbívoros. Su número y morfología dependerá de la dieta vegetal de estos animales. El estudio que aquí se presenta se centra en el análisis microscópico de ambos elementos, fitolitos y esferulitas, identificados en restos fecales, de varios animales herbívoros, recolectados durante la estación seca en la Garganta de Olduvai en Tanzania. Los fitolitos y las esferulitas fueron identificados y analizados siguiendo un método morfológico y cuantitativo. Los fitolitos fueron luego comparados con una colección de referencia de plantas modernas de la misma zona geográfica con el propósito de estudiar la dieta de cada uno de los animales analizados. Finalmente los resultados fueron relacionados con los obtenidos del estudio de esferulitas, con el propósito de analizar la relación entre morfología y número de fitolitos y morfología y número de esferulitas para cada uno de los restos fecales analizados. El objetivo de este trabajo consiste en evaluar la utilidad de combinar ambas técnicas para identificar restos fecales en el registro arqueológico y, consecuentemente, responder a cuestiones relacionadas con el animal productor de estos restos, su dieta y movimientos migratorios y, paralelamente, la paleovegetación y el paleopaisaje en una región determinada.

Development of a GPS-Based Sign Inventory Tool for Iowa’s Statewide Management System, May 2011

This report is on state-of-the-art research efforts specific to infrastructure inventory/data collection with sign inventory as a case study. The development of an agency-wide sign inventory is based on feature inventory and location information. Specific to location, a quick and simple location acquisition tool is critical to tying assets to an accurate location-referencing system. This research effort provides a contrast between legacy referencing systems (route and milepost) and global positioning system- (GPS-) based techniques (latitude and longitude) integrated into a geographic information system (GIS) database. A summary comparison of field accuracies using a variety of consumer grade devices is also provided. This research, and the data collection tools developed, are critical in supporting the Iowa Department of Transportation (DOT) Statewide Sign Management System development effort. For the last two years, a Task Force has embarked on a comprehensive effort to develop a sign management system to improve sign quality, as well as to manage all aspects of signage, from request, ordering, fabricating, installing, maintaining, and ultimately removing, and to provide the ability to budget for these key assets on a statewide basis. This effort supported the development of a sign inventory tool and is the beginning of the development of a sign management system to support the Iowa DOT efforts in the consistent, cost effective, and objective decision making process when it comes to signs and their maintenance.

Compliance Monitoring Report Technical Assistance Tool, 2008

This form requests the minimum information required to demonstrate the extent of compliance with section 223(a)(11), 223(a)(12), 223(a)(13), 223(a)(14) of the JJDP Act of 2002. Many of these reporting requirements may be found in 28 C.F.R. 31.303(f)(5).

Compliance Monitoring Report Technical Assistance Tool, 2009

This form requests the minimum information required to demonstrate the extent of compliance with section 223(a)(11), 223(a)(12), 223(a)(13), 223(a)(14) of the JJDP Act of 2002. Many of these reporting requirements may be found in 28 C.F.R. 31.303(f)(5).

A Monte Carlo-based procedure for independent monitor unit calculation in IMRT treatment plans.

Intensity-modulated radiotherapy (IMRT) treatment plan verification by comparison with measured data requires having access to the linear accelerator and is time consuming. In this paper, we propose a method for monitor unit (MU) calculation and plan comparison for step and shoot IMRT based on the Monte Carlo code EGSnrc/BEAMnrc. The beamlets of an IMRT treatment plan are individually simulated using Monte Carlo and converted into absorbed dose to water per MU. The dose of the whole treatment can be expressed through a linear matrix equation of the MU and dose per MU of every beamlet. Due to the positivity of the absorbed dose and MU values, this equation is solved for the MU values using a non-negative least-squares fit optimization algorithm (NNLS). The Monte Carlo plan is formed by multiplying the Monte Carlo absorbed dose to water per MU with the Monte Carlo/NNLS MU. Several treatment plan localizations calculated with a commercial treatment planning system (TPS) are compared with the proposed method for validation. The Monte Carlo/NNLS MUs are close to the ones calculated by the TPS and lead to a treatment dose distribution which is clinically equivalent to the one calculated by the TPS. This procedure can be used as an IMRT QA and further development could allow this technique to be used for other radiotherapy techniques like tomotherapy or volumetric modulated arc therapy.

Alkaline phosphatase activity as a tool for assessing nutritional conditions in the seagrass Posidonia oceanica.(L.) Delile

The effects of experimental phosphorus enrichments on alkaline phosphatase activity (APA) of the seagrass Posidonia oceanica (L.) Delile were tested. Short-term additions (as phosphate, 12 hours, in the laboratory) decreased APA by 18-2896, depending on the plant part considered (roots, young leaves or old leaves). The values of APA after this treatment were well correlated with interna1 phosphorus pools (as P concentration in plant tissues). Long-term additions (as phosphate, added to the sediment, 1 month in situ) decreased APA by 40-75%, also depending on the plant part. We conclude that alkaline phosphatase activity is a good indicator of P deficiency in this seagrass. We used this indicator to assess the P-nutritional status in a series of meadows in the NW Mediterranean, finding a high geographical variability, but correlations between APA and basic features of the meadows (carbonate content of the sediment, organic content of the sediment, shoot density, etc.) were not significant. Consequently, phosphorus deficiency does not seem to be directly related to these descriptors.

MBIS: multivariate Bayesian image segmentation tool.

We present MBIS (Multivariate Bayesian Image Segmentation tool), a clustering tool based on the mixture of multivariate normal distributions model. MBIS supports multichannel bias field correction based on a B-spline model. A second methodological novelty is the inclusion of graph-cuts optimization for the stationary anisotropic hidden Markov random field model. Along with MBIS, we release an evaluation framework that contains three different experiments on multi-site data. We first validate the accuracy of segmentation and the estimated bias field for each channel. MBIS outperforms a widely used segmentation tool in a cross-comparison evaluation. The second experiment demonstrates the robustness of results on atlas-free segmentation of two image sets from scan-rescan protocols on 21 healthy subjects. Multivariate segmentation is more replicable than the monospectral counterpart on T1-weighted images. Finally, we provide a third experiment to illustrate how MBIS can be used in a large-scale study of tissue volume change with increasing age in 584 healthy subjects. This last result is meaningful as multivariate segmentation performs robustly without the need for prior knowledge.

Are patients at nutritional risk more prone to complications after major urological surgery?

PURPOSE: The nutritional risk score is a recommended screening tool for malnutrition. While a nutritional risk score of 3 or greater predicts adverse outcomes after digestive surgery, to our knowledge its predictive value for morbidity after urological interventions is unknown. We determined whether urological patients at nutritional risk are at higher risk for complications after major surgery than patients not at nutritional risk. MATERIALS AND METHODS: We performed a prospective observational study in consecutive patients undergoing major surgery. A priori sample calculation resulted in a study cohort of 220 patients. Interim analysis was planned after 110 patients. The nutritional risk score was assessed preoperatively by a specialized study nurse. Nutritional care was standardized in all patients. Postoperative complications were defined previously using the standardized Dindo-Clavien classification. The primary end point was 30-day morbidity. Univariate and multivariate analysis was performed to identify predictors of complications. RESULTS: The study was discontinued due to significant results after interim analysis. A total of 125 patients were included in analysis from June 2011 to June 2012 and 15 were excluded because of incomplete data. Of 51 patients at nutritional risk 38 (74%) presented with at least 1 complication compared to 28 of 59 controls (47%). Patients at nutritional risk were at threefold risk for complications on univariate and multivariate analysis (OR 3.3, 95% CI 1.3-8.0). Cystectomy was the only other predictor of morbidity (OR 10, 95% CI 2-48). CONCLUSIONS: Patients at nutritional risk are more prone to complications after major urological procedures. Whether this increased morbidity can be reversed by perioperative nutritional support should be studied.

Morphological Study of Intracardiac Signals as a New Tool to Track the Efficiency of Stepwise Ablation of Persistent Atrial Fibrillation

Intracardiac organization indices such as atrial fibrillation (AF) cycle length (AFCL) have been used to track the efficiency of stepwise catheter ablation (step-CA) of longstanding persistent AF, however with limited success. The morphology of AF activation waves reflects the underlying activation patterns. Its temporal evolution is a local organization indicator that could be potentially used for tracking the efficiency of step-CA. We report a new method for characterizing the structure of the temporal evolution of activation wave morphology. Using recurrence plots, novel organization indices are proposed. By computing their relative evolution during the first step of ablation vs baseline, we found that these new parameters are superior to AFCL to track the effect of step-CA "en route" to AF termination.