Comparative methodology to investigate the presence of Escherichia coli K-12 strains in environmental and human stool samples

This study was undertaken to evaluate the specificity and efficiency of different methods to detect Escherichia coli K-12 strains. Another aim was to determine the frequency of E. coli K-12 strains among wild-type E. coli isolates from different sources. The detection of K-12 strains was performed both genotypically by K-12 specific polymerase chain reaction (PCR) and on the basis of phenotypical tests. In addition, the genome structures of E. coli strains were characterized by pulsed-field gel electrophoresis (PFGE). The most specific results could be obtained by the genotypical tests PCR and PFGE as well as by the K-12 specific phage assay. In total, 131 stool and 95 water isolates as well as 14 K-12 derivatives were examined by the different methods. No E. coli K-12 strains were detected among the wild-type isolates.

Methodology for GPS Synchronization Evaluation with High Accuracy

Clock synchronization in the order of nanoseconds is one of the critical factors for time-based localization. Currently used time synchronization methods are developed for the more relaxed needs of network operation. Their usability for positioning should be carefully evaluated. In this paper, we are particularly interested in GPS-based time synchronization. To judge its usability for localization we need a method that can evaluate the achieved time synchronization with nanosecond accuracy. Our method to evaluate the synchronization accuracy is inspired by signal processing algorithms and relies on fine grain time information. The method is able to calculate the clock offset and skew between devices with nanosecond accuracy in real time. It was implemented using software defined radio technology. We demonstrate that GPS-based synchronization suffers from remaining clock offset in the range of a few hundred of nanoseconds but the clock skew is negligible. Finally, we determine a corresponding lower bound on the expected positioning error.

A complete-pelvis segmentation framework for image-free total hip arthroplasty (THA): methodology and clinical study

Background Complete-pelvis segmentation in antero-posterior pelvic radiographs is required to create a patient-specific three-dimensional pelvis model for surgical planning and postoperative assessment in image-free navigation of total hip arthroplasty. Methods A fast and robust framework for accurately segmenting the complete pelvis is presented, consisting of two consecutive modules. In the first module, a three-stage method was developed to delineate the left hemipelvis based on statistical appearance and shape models. To handle complex pelvic structures, anatomy-specific information processing techniques were employed. As the input to the second module, the delineated left hemi-pelvis was then reflected about an estimated symmetry line of the radiograph to initialize the right hemi-pelvis segmentation. The right hemi-pelvis was segmented by the same three-stage method, Results Two experiments conducted on respectively 143 and 40 AP radiographs demonstrated a mean segmentation accuracy of 1.61±0.68 mm. A clinical study to investigate the postoperative assessment of acetabular cup orientations based on the proposed framework revealed an average accuracy of 1.2°±0.9° and 1.6°±1.4° for anteversion and inclination, respectively. Delineation of each radiograph costs less than one minute. Conclusions Despite further validation needed, the preliminary results implied the underlying clinical applicability of the proposed framework for image-free THA.

A methodology for appraising and selecting strategies to mitigate desertification based on stakeholder participation and global best practices

The main aim of the methodology presented in this paper is to provide a framework for a participatory process for the appraisal and selection of options to mitigate desertification and land degradation. This methodology is being developed within the EU project DESIRE (www.desire-project.eu/) in collaboration with WOCAT (www.wocat.org). It is used to select promising conservation strategies for test-implementation in each of the 16 degradation and desertification hotspot sites in the Mediterranean and around the world. The methodology consists of three main parts: In a first step, prevention and mitigation strategies already applied at the respective DESIRE study site are identified and listed during a workshop with representatives of different stakeholders groups (land users, policy makers, researchers). The participatory and process-oriented approach initiates a mutual learning process among the different stakeholders by sharing knowledge and jointly reflecting on current problems and solutions related to land degradation and desertification. In the second step these identified, locally applied solutions (technologies and approaches) are assessed with the help of the WOCAT methodology. Comprehensive questionnaires and a database system have been developed to document and evaluate all relevant aspects of technical measures as well as implementation approaches by teams of researchers and specialists, together with land users. This research process ensures systematic assessing and piecing together of local information, together with specific details about the environmental and socio-economic setting. The third part consists of another stakeholder workshop where promising strategies for sustainable land management in the given context are selected, based on the best practices database of WOCAT, including the evaluated locally applied strategies at the DESIRE sites. These promising strategies will be assessed with the help of a selection and decision support tool and adapted for test-implementation at the study site.

Introduction to the Talmud : historical and literary introduction, legal hermeneutics of the talmud, talmudical terminology and methodology, outlines of talmudical ethics

by M. Mielziner. With add. notes by Joshua Bloch ...

Comparison of proximal femur and vertebral body strength improvements in the FREEDOM trial using an alternative finite element methodology

Denosumab reduced the incidence of new fractures in postmenopausal women with osteoporosis by 68% at the spine and 40% at the hip over 36 months compared with placebo in the FREEDOM study. This efficacy was supported by improvements from baseline in vertebral (18.2%) strength in axial compression and femoral (8.6%) strength in sideways fall configuration at 36 months, estimated in Newtons by an established voxel-based finite element (FE) methodology. Since FE analyses rely on the choice of meshes, material properties, and boundary conditions, the aim of this study was to independently confirm and compare the effects of denosumab on vertebral and femoral strength during the FREEDOM trial using an alternative smooth FE methodology. Unlike the previous FE study, effects on femoral strength in physiological stance configuration were also examined. QCT data for the proximal femur and two lumbar vertebrae were analyzed by smooth FE methodology at baseline, 12, 24, and 36 months for 51 treated (denosumab) and 47 control (placebo) subjects. QCT images were segmented and converted into smooth FE models to compute bone strength. L1 and L2 vertebral bodies were virtually loaded in axial compression and the proximal femora in both fall and stance configurations. Denosumab increased vertebral body strength by 10.8%, 14.0%, and 17.4% from baseline at 12, 24, and 36 months, respectively (p < 0.0001). Denosumab also increased femoral strength in the fall configuration by 4.3%, 5.1%, and 7.2% from baseline at 12, 24, and 36 months, respectively (p < 0.0001). Similar improvements were observed in the stance configuration with increases of 4.2%, 5.2%, and 5.2% from baseline (p ≤ 0.0007). Differences between the increasing strengths with denosumab and the decreasing strengths with placebo were significant starting at 12 months (vertebral and femoral fall) or 24 months (femoral stance). Using an alternative smooth FE methodology, we confirmed the significant improvements in vertebral body and proximal femur strength previously observed with denosumab. Estimated increases in strength with denosumab and decreases with placebo were highly consistent between both FE techniques.

Get real in individual participant data (IPD) meta-analysis: a review of the methodology.

Individual participant data (IPD) meta-analysis is an increasingly used approach for synthesizing and investigating treatment effect estimates. Over the past few years, numerous methods for conducting an IPD meta-analysis (IPD-MA) have been proposed, often making different assumptions and modeling choices while addressing a similar research question. We conducted a literature review to provide an overview of methods for performing an IPD-MA using evidence from clinical trials or non-randomized studies when investigating treatment efficacy. With this review, we aim to assist researchers in choosing the appropriate methods and provide recommendations on their implementation when planning and conducting an IPD-MA. © 2015 The Authors. Research Synthesis Methods published by John Wiley & Sons, Ltd.

GetReal in network meta-analysis: a review of the methodology.

Pairwise meta-analysis is an established statistical tool for synthesizing evidence from multiple trials, but it is informative only about the relative efficacy of two specific interventions. The usefulness of pairwise meta-analysis is thus limited in real-life medical practice, where many competing interventions may be available for a certain condition and studies informing some of the pairwise comparisons may be lacking. This commonly encountered scenario has led to the development of network meta-analysis (NMA). In the last decade, several applications, methodological developments, and empirical studies in NMA have been published, and the area is thriving as its relevance to public health is increasingly recognized. This article presents a review of the relevant literature on NMA methodology aiming to pinpoint the developments that have appeared in the field. Copyright © 2016 John Wiley & Sons, Ltd.

Quantitative multi-slice computed tomography assessment of the mitral valvular complex for transcatheter mitral valve interventions part 1: systematic measurement methodology and inter-observer variability

AIMS Transcatheter mitral valve replacement (TMVR) is an emerging technology with the potential to treat patients with severe mitral regurgitation at excessive risk for surgical mitral valve surgery. Multimodal imaging of the mitral valvular complex and surrounding structures will be an important component for patient selection for TMVR. Our aim was to describe and evaluate a systematic multi-slice computed tomography (MSCT) image analysis methodology that provides measurements relevant for transcatheter mitral valve replacement. METHODS AND RESULTS A systematic step-by-step measurement methodology is described for structures of the mitral valvular complex including: the mitral valve annulus, left ventricle, left atrium, papillary muscles and left ventricular outflow tract. To evaluate reproducibility, two observers applied this methodology to a retrospective series of 49 cardiac MSCT scans in patients with heart failure and significant mitral regurgitation. For each of 25 geometrical metrics, we evaluated inter-observer difference and intra-class correlation. The inter-observer difference was below 10% and the intra-class correlation was above 0.81 for measurements of critical importance in the sizing of TMVR devices: the mitral valve annulus diameters, area, perimeter, the inter-trigone distance, and the aorto-mitral angle. CONCLUSIONS MSCT can provide measurements that are important for patient selection and sizing of TMVR devices. These measurements have excellent inter-observer reproducibility in patients with functional mitral regurgitation.

H/L ratio as a measurement of stress in laying hens - methodology and reliability.

Measuring the ratio of heterophils and lymphocytes (H/L) in response to different stressors is a standard tool for assessing long-term stress in laying hens but detailed information on the reliability of measurements, measurement techniques and methods, and absolute cell counts is often lacking. Laying hens offered different sites of the nest boxes at different ages were compared in a two-treatment crossover experiment to provide detailed information on the procedure for measuring and the difficulties in the interpretation of H/L ratios in commercial conditions. H/L ratios were pen-specific and depended on the age and aviary system. There was no effect for the position of the nest. Heterophiles and lymphocytes were not correlated within individuals. Absolute cell counts differed in the number of heterophiles and lymphocytes and H/L ratios, whereas absolute leucocyte counts between individuals were similar. The reliability of the method using relative cell counts was good, yielding a correlation coefficient between double counts of r > 0.9. It was concluded that population-based reference values may not be sensitive enough to detect individual stress reactions and that the H/L ratio as an indicator of stress under commercial conditions may not be useful because of confounding factors and that other, non-invasive, measurements should be adopted.

SAMPLING METHODOLOGY FOR AIRBORNE SEMIVOLATILE ORGANIC POLLUTANTS USING POLYURETHANE FOAMS (COLLECTION, PESTICIDES, VOLATILE)

Indoor and ambient air organic pollutants have been gaining attention because they have been measured at levels with possible health effects. Studies have shown that most airborne polychlorinated biphenyls (PCBs), pesticides and many polycyclic aromatic hydrocarbons (PAHs) are present in the free vapor state. The purpose of this research was to extend recent investigative work with polyurethane foam (PUF) as a collection medium for semivolatile compounds. Open-porous flexible PUFs with different chemical makeup and physical properties were evaluated as to their collection affinities/efficiencies for various classes of compounds and the degree of sample recovery. Filtered air samples were pulled through plugs of PUF spiked with various semivolatiles under different simulated environmental conditions (temperature and humidity), and sampling parameters (flow rate and sample volume) in order to measure their effects on sample breakthrough volume (V(,B)). PUF was also evaluated in the passive mode using organo-phosphorus pesticides. Another major goal was to improve the overall analytical methodology; PUF is inexpensive, easy to handle in the field and has excellent airflow characteristics (low pressure drop). It was confirmed that the PUF collection apparatus behaves as if it were a gas-solid chromatographic system, in that, (V(,B)) was related to temperature and sample volume. Breakthrough volumes were essentially the same using both polyether and polyester type PUF. Also, little change was observed in the V(,B)s after coating PUF with common chromatographic liquid phases. Open cell (reticulated) foams gave better recoveries than closed cell foams. There was a slight increase in (V(,B)) with an increase in the number of cells/pores per inch. The high-density polyester PUF was found to be an excellent passive and active collection adsorbent. Good recoveries could be obtained using just solvent elution. A gas chromatograph equipped with a photoionization detector gave excellent sensitivities and selectivities for the various classes of compounds investigated. ^

A novel treatment planning methodology for high dose 166Ho-DOTMP therapy in patients with multiple myeloma

Bone marrow ablation, i.e., the complete sterilization of the active bone marrow, followed by bone marrow transplantation (BMT) is a comment treatment of hematological malignancies. The use of targeted bone-seeking radiopharmaceuticals to selectively deliver radiation to the adjacent bone marrow cavities while sparing normal tissues is a promising technique. Current radiopharmaceutical treatment planning methods do not properly compensate for the patient-specific variable distribution of radioactive material within the skeleton. To improve the current method of internal dosimetry, novel methods for measuring the radiopharmaceutical distribution within the skeleton were developed. 99mTc-MDP was proven as an adequate surrogate for measuring 166Ho-DOTMP skeletal uptake and biodistribution, allowing these measures to be obtained faster, safer, and with higher spatial resolution. This translates directly into better measurements of the radiation dose distribution within the bone marrow. The resulting bone marrow dose-volume histograms allow prediction of the patient disease response where conventional organ scale dosimetry failed. They indicate that complete remission is only achieved when greater than 90% of the bone marrow receives at least 30 Gy. ^ Comprehensive treatment planning requires combining target and non-target organ dosimetry. Organs in the urinary tract were of special concern. The kidney dose is primarily dependent upon the mean transit time of 166 Ho-DOTMP through the kidney. Deconvolution analysis of renograms predicted a mean transit time of 2.6 minutes for 166Ho-DOTMP. The radiation dose to the urinary bladder wall is dependent upon numerous factors including patient hydration and void schedule. For beta-emitting isotopes such as 166Ho, reduction of the bladder wall dose is best accomplished through good patient hydration and ensuring a partially full bladder at the time of injection. Encouraging the patient to void frequently, or catheterizing the patient without irrigation, will not significantly reduce the bladder wall dose. ^ The results from this work will produce the most advanced treatment planning methodology for bone marrow ablation therapy using radioisotopes currently available. Treatments can be tailored specifically for each patient, including the addition of concomitant total body irradiation for patients with unfavorable dose distributions, to deliver a desired patient disease response, while minimizing the dose or toxicity to non-target organs. ^

Measuring Middle School Achievement Growth With Student Growth Percentile Methodology

This study examined reading and mathematics achievement growth for middle school students over three years using statewide test scores using student growth percentile methodology (Betebenner, 2008). This newly-emerging growth methodology provides a basis for examining growth normatively (“what is”) in order to provide a foundation for policies about adequate growth (“what should be”) and excellent growth (“what could be”). Growth is compared among student subgroups and different middle schools. A particular focus of the study is identifying typical growth trajectories of low-achieving 6th graders through the middle school years.