Science.gov

Sample records for index susceptibility method

  1. Index for surface coherence (ISC): a method for calculating change susceptibility

    NASA Astrophysics Data System (ADS)

    Tran, Jonathan

    2016-05-01

    Coherent change detection (CCD) provides a way for analysts and detectors to find ephemeral features that would otherwise be invisible in traditional synthetic aperture radar (SAR) imagery. However, CCD can produce false alarms in regions of the image that have low SNR and high vegetation areas. The method proposed looks to eliminate these false alarm regions by creating a mask which can then be applied to change products. This is done by utilizing both the magnitude and coherence feature statistics of a scene. For each feature, the image is segmented into groups of similar pixels called superpixels. The method then utilizes a training phase to model each terrain that the user deems as capable of supporting change and statistically comparing superpixels in the image to the modeled terrain types. Finally, the method combines the features using probabilistic fusion to create a mask that a user can threshold and apply to a change product for human analysis or automatic feature detectors.

  2. Continental Portuguese Territory Flood Social Susceptibility Index

    NASA Astrophysics Data System (ADS)

    Grosso, N.; Dias, L.; Costa, H. P.; Santos, F. D.; Garrett, P.

    2014-12-01

    The combination of human exposure, extreme weather events and lack of adaptation strategies to cope with flood related impacts can potentially increase losses not only on infrastructure but also on human lives. These impacts are usually difficult to quantify due to the lack of data and for this reason most of the studies developed at the national scale only include the main characteristics that define the societal or individual predisposition to be affected, resist, adapt or recover, when exposed to a flood. The main objective of this work was to develop a flood social susceptibility index for the continental Portuguese territory based on the most representative variables able to characterize different influencing factors. This index is part of the national vulnerability index developed in the scope of Flood Maps in Climate Change Scenarios (CIRAC) project, supported by the Portuguese Association of Insurers (APS). The main results showed that the proposed index correctly identified populations more socially susceptible to floods, mostly concentrated in rural inland areas with lower income and education levels, when compared with the coastal region between Viana do Castelo and Setúbal.

  3. Continental Portuguese Territory Flood Social Susceptibility Index

    NASA Astrophysics Data System (ADS)

    Grosso, N.; Dias, L.; Costa, H. P.; Santos, F. D.; Garrett, P.

    2015-08-01

    The combination of human exposure, extreme weather events and lack of adaptation strategies to cope with flood-related impacts can potentially increase losses not only on infrastructure but also on human lives. These impacts are usually difficult to quantify due to the lack of data, and for this reason most of the studies developed at the national scale only include the main characteristics that define the societal or individual predisposition to be affected, resist, adapt or recover, when exposed to a flood. The main objective of this work was to develop a flood social susceptibility index for the continental Portuguese territory based on the most representative variables able to characterize different influencing factors. This index is a component of the national vulnerability index developed in the scope of Flood Maps in Climate Change Scenarios (CIRAC) project, supported by the Portuguese Association of Insurers (APS). The main results showed that the proposed index correctly identified populations less prepared to avoid flood effects or able to cope with them, mostly concentrated in rural inland areas with lower income and education levels when compared with the coastal region between Viana do Castelo and Setúbal.

  4. Assessment of groundwater vulnerability by combining drastic and susceptibility index: Application to Annaba superficial aquifer (Algeria)

    NASA Astrophysics Data System (ADS)

    Sedrati, Nassima; Djabri, Larbi; Chaffai, Hicham; Bougherira, Nabil

    2016-07-01

    Groundwater pollution due to anthropogenic activities is one of the major environmental problems in urban and industrial areas. The aim of this work is to propose a new integrated methodology to assess actual and forecasted groundwater vulnerability by combining Drastic and susceptibility index. The contamination susceptibility index (SI) at a given location was calculated by taking the product of the vulnerability DRASTIC index (VI) and the quality index (QI): SI=VI x QI. The superficial aquifer of Annaba plain was the study case proposed for the application of this methodology. The study revealed that the area with Very High vulnerability would increase 73 % in this superficial layer. This result can be explained by the susceptibility index map shows both hydrogeological and hydrochemical data related to the contamination problem including areas that should be taken into consideration during water management planning. The index map indicates that the most susceptible groundwater is occupies the majority of the study area. The validity of the DRASTIC and the susceptibility index methods, verified by comparing the distribution of some pollutants (Daouad, 2013) in the groundwater and the different vulnerability classes, shows a high contamination that affect the water quality in study areas.

  5. Using the statistical analysis method to assess the landslide susceptibility

    NASA Astrophysics Data System (ADS)

    Chan, Hsun-Chuan; Chen, Bo-An; Wen, Yo-Ting

    2015-04-01

    This study assessed the landslide susceptibility in Jing-Shan River upstream watershed, central Taiwan. The landslide inventories during typhoons Toraji in 2001, Mindulle in 2004, Kalmaegi and Sinlaku in 2008, Morakot in 2009, and the 0719 rainfall event in 2011, which were established by Taiwan Central Geological Survey, were used as landslide data. This study aims to assess the landslide susceptibility by using different statistical methods including logistic regression, instability index method and support vector machine (SVM). After the evaluations, the elevation, slope, slope aspect, lithology, terrain roughness, slope roughness, plan curvature, profile curvature, total curvature, average of rainfall were chosen as the landslide factors. The validity of the three established models was further examined by the receiver operating characteristic curve. The result of logistic regression showed that the factor of terrain roughness and slope roughness had a stronger impact on the susceptibility value. Instability index method showed that the factor of terrain roughness and lithology had a stronger impact on the susceptibility value. Due to the fact that the use of instability index method may lead to possible underestimation around the river side. In addition, landslide susceptibility indicated that the use of instability index method laid a potential issue about the number of factor classification. An increase of the number of factor classification may cause excessive variation coefficient of the factor. An decrease of the number of factor classification may make a large range of nearby cells classified into the same susceptibility level. Finally, using the receiver operating characteristic curve discriminate the three models. SVM is a preferred method than the others in assessment of landslide susceptibility. Moreover, SVM is further suggested to be nearly logistic regression in terms of recognizing the medium-high and high susceptibility.

  6. Computing discharge using the index velocity method

    USGS Publications Warehouse

    Levesque, Victor A.; Oberg, Kevin A.

    2012-01-01

    Application of the index velocity method for computing continuous records of discharge has become increasingly common, especially since the introduction of low-cost acoustic Doppler velocity meters (ADVMs) in 1997. Presently (2011), the index velocity method is being used to compute discharge records for approximately 470 gaging stations operated and maintained by the U.S. Geological Survey. The purpose of this report is to document and describe techniques for computing discharge records using the index velocity method. Computing discharge using the index velocity method differs from the traditional stage-discharge method by separating velocity and area into two ratings—the index velocity rating and the stage-area rating. The outputs from each of these ratings, mean channel velocity (V) and cross-sectional area (A), are then multiplied together to compute a discharge. For the index velocity method, V is a function of such parameters as streamwise velocity, stage, cross-stream velocity, and velocity head, and A is a function of stage and cross-section shape. The index velocity method can be used at locations where stage-discharge methods are used, but it is especially appropriate when more than one specific discharge can be measured for a specific stage. After the ADVM is selected, installed, and configured, the stage-area rating and the index velocity rating must be developed. A standard cross section is identified and surveyed in order to develop the stage-area rating. The standard cross section should be surveyed every year for the first 3 years of operation and thereafter at a lesser frequency, depending on the susceptibility of the cross section to change. Periodic measurements of discharge are used to calibrate and validate the index rating for the range of conditions experienced at the gaging station. Data from discharge measurements, ADVMs, and stage sensors are compiled for index-rating analysis. Index ratings are developed by means of regression

  7. Susceptibility index to surface contamination for the Little Cross Creek watershed, Cumberland County, North Carolina

    USGS Publications Warehouse

    Giorgino, M.J.; Terziotti, Silvia

    2001-01-01

    support the results of the susceptibility analysis. Although this susceptibility index is specific to the Little Cross Creek Basin, the methods used to develop the index are transferable to other watersheds.

  8. Continental Portuguese Territory Flood Susceptibility Index - contribution to a vulnerability index

    NASA Astrophysics Data System (ADS)

    Jacinto, R.; Grosso, N.; Reis, E.; Dias, L.; Santos, F. D.; Garrett, P.

    2015-08-01

    This work defines a national flood susceptibility index for the Portuguese continental territory, by proposing the aggregation of different variables which represent natural conditions for permeability, runoff and accumulation. This index is part of the national vulnerability index developed in the scope of Flood Maps in Climate Change Scenarios (CIRAC) project, supported by the Portuguese Association of Insurers (APS). This approach expands on previous works by trying to bridge the gap between different flood mechanisms (e.g. progressive and flash floods) occurring at different spatial scales in the Portuguese territory through (a) selecting homogeneously processed data sets and (b) aggregating their values to better translate the spatially continuous and cumulative influence in floods at multiple spatial scales. Results show a good ability to capture, in the higher susceptibility classes, different flood types: fluvial floods and flash floods. Lower values are usually related to mountainous areas, low water accumulation potential and more permeable soils. Validation with independent flood data sets confirmed these index characteristics, although some overestimation can be seen in the southern region of Alentejo where, due to a dense hydrographic network and an overall low slope, floods are not as frequent as a result of lower precipitation mean values. Future work will focus on (i) including extreme precipitation data sets to represent the triggering factor, (ii) improving representation of smaller and stepper basins, (iii) optimizing variable weight definition process and (iii) developing more robust independent flood validation data sets.

  9. Continental Portuguese Territory Flood Susceptibility Index - contribution for a vulnerability index

    NASA Astrophysics Data System (ADS)

    Jacinto, R.; Grosso, N.; Reis, E.; Dias, L.; Santos, F. D.; Garrett, P.

    2014-12-01

    This work defines a national flood susceptibility index for the Portuguese continental territory, by proposing the aggregation of different variables which represent natural conditions for permeability, runoff and accumulation. This index is part of the national vulnerability index developed in the scope of Flood Maps in Climate Change Scenarios (CIRAC) project, supported by the Portuguese Association of Insurers (APS). This approach expands on previous works by trying to bridge the gap between different floods mechanisms (e.g. progressive and flash floods) occurring at different spatial scales in the Portuguese territory through: (a) selecting homogeneously processed datasets, (b) aggregating their values to better translate the spatially continuous and cumulative influence in floods at multiple spatial scales. Results show a good ability to capture, in the higher susceptibility classes, different flood types: progressive floods and flash floods. Lower values are usually related to: mountainous areas, low water accumulation potential and more permeable soils. Validation with independent flood datasets confirmed these index characteristics, although some overestimation can be seen in the southern region of Alentejo where, due to a dense hydrographic network and an overall low slope, floods are not as frequent as a result of lower precipitation mean values. Future work will focus on: (i) including extreme precipitation datasets to represent the triggering factor, (ii) improving representation of smaller and stepper basins, (iii) optimizing variable weight definition process, (iii) developing more robust independent flood validation datasets.

  10. Absolute method of measuring magnetic susceptibility

    USGS Publications Warehouse

    Thorpe, A.; Senftle, F.E.

    1959-01-01

    An absolute method of standardization and measurement of the magnetic susceptibility of small samples is presented which can be applied to most techniques based on the Faraday method. The fact that the susceptibility is a function of the area under the curve of sample displacement versus distance of the magnet from the sample, offers a simple method of measuring the susceptibility without recourse to a standard sample. Typical results on a few substances are compared with reported values, and an error of less than 2% can be achieved. ?? 1959 The American Institute of Physics.

  11. Comparison and applicability of landslide susceptibility models based on landslide ratio-based logistic regression, frequency ratio, weight of evidence, and instability index methods in an extreme rainfall event

    NASA Astrophysics Data System (ADS)

    Wu, Chunhung

    2016-04-01

    Few researches have discussed about the applicability of applying the statistical landslide susceptibility (LS) model for extreme rainfall-induced landslide events. The researches focuses on the comparison and applicability of LS models based on four methods, including landslide ratio-based logistic regression (LRBLR), frequency ratio (FR), weight of evidence (WOE), and instability index (II) methods, in an extreme rainfall-induced landslide cases. The landslide inventory in the Chishan river watershed, Southwestern Taiwan, after 2009 Typhoon Morakot is the main materials in this research. The Chishan river watershed is a tributary watershed of Kaoping river watershed, which is a landslide- and erosion-prone watershed with the annual average suspended load of 3.6×107 MT/yr (ranks 11th in the world). Typhoon Morakot struck Southern Taiwan from Aug. 6-10 in 2009 and dumped nearly 2,000 mm of rainfall in the Chishan river watershed. The 24-hour, 48-hour, and 72-hours accumulated rainfall in the Chishan river watershed exceeded the 200-year return period accumulated rainfall. 2,389 landslide polygons in the Chishan river watershed were extracted from SPOT 5 images after 2009 Typhoon Morakot. The total landslide area is around 33.5 km2, equals to the landslide ratio of 4.1%. The main landslide types based on Varnes' (1978) classification are rotational and translational slides. The two characteristics of extreme rainfall-induced landslide event are dense landslide distribution and large occupation of downslope landslide areas owing to headward erosion and bank erosion in the flooding processes. The area of downslope landslide in the Chishan river watershed after 2009 Typhoon Morakot is 3.2 times higher than that of upslope landslide areas. The prediction accuracy of LS models based on LRBLR, FR, WOE, and II methods have been proven over 70%. The model performance and applicability of four models in a landslide-prone watershed with dense distribution of rainfall

  12. Sparse methods for Quantitative Susceptibility Mapping

    NASA Astrophysics Data System (ADS)

    Bilgic, Berkin; Chatnuntawech, Itthi; Langkammer, Christian; Setsompop, Kawin

    2015-09-01

    Quantitative Susceptibility Mapping (QSM) aims to estimate the tissue susceptibility distribution that gives rise to subtle changes in the main magnetic field, which are captured by the image phase in a gradient echo (GRE) experiment. The underlying susceptibility distribution is related to the acquired tissue phase through an ill-posed linear system. To facilitate its inversion, spatial regularization that imposes sparsity or smoothness assumptions can be employed. This paper focuses on efficient algorithms for regularized QSM reconstruction. Fast solvers that enforce sparsity under Total Variation (TV) and Total Generalized Variation (TGV) constraints are developed using Alternating Direction Method of Multipliers (ADMM). Through variable splitting that permits closed-form iterations, the computation efficiency of these solvers are dramatically improved. An alternative approach to improve the conditioning of the ill-posed inversion is to acquire multiple GRE volumes at different head orientations relative to the main magnetic field. The phase information from such multi-orientation acquisition can be combined to yield exquisite susceptibility maps and obviate the need for regularized reconstruction, albeit at the cost of increased data acquisition time.

  13. Transverse susceptibility method in nanoparticulate magnetic media.

    PubMed

    Cimpoesu, Dorin; Spinu, Leonard; Stancu, Alexandru

    2008-06-01

    Transverse susceptibility (TS) method is a reliable method for the determination of anisotropy in nanoparticulate media. To correctly evaluate the value of anisotropy in various modern nanostructured materials, a number of theoretical problems related to the method have to be well understood to avoid significant systematic errors. This paper presents the state of the art in the TS method which includes the expression for single domain particles with any type of anisotropy, the theoretical and micromagnetic, using Landau-Lifshitz-Gilbert (LLG) equation and stochastic LLG equation studies of the effects of ac field amplitude, inter-particle interactions, and magnetic relaxation. The problem of both real and imaginary parts of the TS signal is also discussed. PMID:18681012

  14. An automatic indexing method for medical documents.

    PubMed Central

    Wagner, M. M.

    1991-01-01

    This paper describes MetaIndex, an automatic indexing program that creates symbolic representations of documents for the purpose of document retrieval. MetaIndex uses a simple transition network parser to recognize a language that is derived from the set of main concepts in the Unified Medical Language System Metathesaurus (Meta-1). MetaIndex uses a hierarchy of medical concepts, also derived from Meta-1, to represent the content of documents. The goal of this approach is to improve document retrieval performance by better representation of documents. An evaluation method is described, and the performance of MetaIndex on the task of indexing the Slice of Life medical image collection is reported. PMID:1807564

  15. Association between the interaction of SMAD3 polymorphisms with body mass index and osteoarthritis susceptibility

    PubMed Central

    Kang, Baolin; Zhao, Feng; Zhang, Xin; Deng, Xiao; He, Xijing

    2015-01-01

    Purpose: This study aimed to investigate the relationship between the interaction of SMAD3 polymorphisms (rs12102171 and rs2289263) with body mass index (BMI) and osteoarthritis (OA) susceptibility. Methods: This study involved 112 OA patients and 120 healthy people. The controls were frequency-matched with the cases by age and sex. Hardy-Weinberg equilibrium (HWE) was tested by χ2 test in the control group. The rs12102171 and rs2289263 polymorphisms were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The relative risk of OA was represented by odds ratio (OR) with 95% confidence interval (CI) calculated by chi-squared test. Gene-environment interaction was analyzed by crossover analysis. Results: The TT genotype and T allele of SMAD3 rs12102171 polymorphism were more frequent in case than control groups (P=0.04 in both of two polymorphisms), which increased the risk of OA (OR=3.39, 95% CI=1.03-11.11 and OR=1.64, 95% CI=1.03-2.59). GG genotype and G allele were also the risk factors for OA (OR=3.22, 95% CI=1.09-9.51 and OR=1.57, 95% CI=1.02-2.42). The BMI had interactions with genotype CC and CT+TT of rs12102171 and TT and TG+GG of rs2289263 (rs12102171: OR=2.15, P=0.02 and OR=3.99, P=1.00×10-3; rs2289263: OR=2.73, P=4.00×10-3 and OR=4.67, P=0). Conclusions: CC and CT+TT and TT and TG+GG genotypes of SMAD3 rs12102171 and rs2289263 polymorphisms together with BMI may be susceptible factors to OA, and interactions there between can possibly confer risk to OA. PMID:26261637

  16. Method of identifying features in indexed data

    DOEpatents

    Jarman, Kristin H [Richland, WA; Daly, Don Simone [Richland, WA; Anderson, Kevin K [Richland, WA; Wahl, Karen L [Richland, WA

    2001-06-26

    The present invention is a method of identifying features in indexed data, especially useful for distinguishing signal from noise in data provided as a plurality of ordered pairs. Each of the plurality of ordered pairs has an index and a response. The method has the steps of: (a) providing an index window having a first window end located on a first index and extending across a plurality of indices to a second window end; (b) selecting responses corresponding to the plurality of indices within the index window and computing a measure of dispersion of the responses; and (c) comparing the measure of dispersion to a dispersion critical value. Advantages of the present invention include minimizing signal to noise ratio, signal drift, varying baseline signal and combinations thereof.

  17. A comparison landslide susceptibility assessment methods in the Luncavat watershed, Romania

    NASA Astrophysics Data System (ADS)

    Irimia, Radu; Cosmin Sandric, Ionut

    2015-04-01

    This paper uses quantitative approaches to generate a landslide susceptibility maps (LSM) for the Luncavăț watershed, located in the Getic Subcarpathians, Romania. The purpose of this study is to evaluate and to compare the results of multivariate and bivariate landslide susceptibility methods. For this study it was decided to use only three predictor factors: slope gradient, lithology and a land-use/land-cover. The study area spreads over approximate 300 km2. This area is highly affected by mass movements, over 65% of the area is moderately or highly susceptible to landslides. Bivariate and multivariate statistical analyses were applied to calculate a landslide susceptibility index. It was found that the results from all the methods converge for aproximate 75% of the Luncavat watershed. However, the bivariate method had some severe deficiencies and parts of the high and medium landslides susceptibility classess did not overlapped with the actual landslide inventory map. The result of the multivariate technique was more sensitive to the different local features of the test zone and it resulted in more accurate and homogeneous susceptibility maps. It is anticipated that the result of this work can be used by local authorithies to help identify high risk landslide areas, and those that are safe for building and other human activities

  18. Engine crankshaft indexing method and tool

    SciTech Connect

    Steffers, T.J.; Feyen, P.A.; Martin, W.R.

    1990-05-08

    This patent describes, in an internal combustion engine having a crankshaft extending axially from a crankcase, a pulley mounted to the crankshaft by a nut, and a disc mounted to the pulley by a plurality of bolts and covering the nut, a method for rotating the crankshaft to facilitate test and repair adjustments requiring precise indexing of rotational degrees of the crankshaft. It comprises: removing one or more of the bolts, removing the disc, providing a tool having a disc and an axial shank, engaging the tool disc with the remaining of the bolts, and rotating the shank to rotate the tool disc to impart rotation to the pulley and the crankshaft.

  19. Landslide Susceptibility Statistical Methods: A Critical and Systematic Literature Review

    NASA Astrophysics Data System (ADS)

    Mihir, Monika; Malamud, Bruce; Rossi, Mauro; Reichenbach, Paola; Ardizzone, Francesca

    2014-05-01

    Landslide susceptibility assessment, the subject of this systematic review, is aimed at understanding the spatial probability of slope failures under a set of geomorphological and environmental conditions. It is estimated that about 375 landslides that occur globally each year are fatal, with around 4600 people killed per year. Past studies have brought out the increasing cost of landslide damages which primarily can be attributed to human occupation and increased human activities in the vulnerable environments. Many scientists, to evaluate and reduce landslide risk, have made an effort to efficiently map landslide susceptibility using different statistical methods. In this paper, we do a critical and systematic landslide susceptibility literature review, in terms of the different statistical methods used. For each of a broad set of studies reviewed we note: (i) study geography region and areal extent, (ii) landslide types, (iii) inventory type and temporal period covered, (iv) mapping technique (v) thematic variables used (vi) statistical models, (vii) assessment of model skill, (viii) uncertainty assessment methods, (ix) validation methods. We then pulled out broad trends within our review of landslide susceptibility, particularly regarding the statistical methods. We found that the most common statistical methods used in the study of landslide susceptibility include logistic regression, artificial neural network, discriminant analysis and weight of evidence. Although most of the studies we reviewed assessed the model skill, very few assessed model uncertainty. In terms of geographic extent, the largest number of landslide susceptibility zonations were in Turkey, Korea, Spain, Italy and Malaysia. However, there are also many landslides and fatalities in other localities, particularly India, China, Philippines, Nepal and Indonesia, Guatemala, and Pakistan, where there are much fewer landslide susceptibility studies available in the peer-review literature. This

  20. Improved method for azole antifungal susceptibility testing.

    PubMed Central

    Gordon, M A; Lapa, E W; Passero, P G

    1988-01-01

    A reproducible method is described for the determination of the MICs of ketoconazole, miconazole, fluconazole, and itraconazole with sharp endpoints when employed with either yeasts or molds. A semisolid medium is used with controlled pH and standardized inoculum. The time of reading results is a critical factor in the conduct of this test. The medium is simple to prepare and has a relatively long refrigerator shelf life in a user-ready state, requiring only the addition of a freshly prepared inoculum after restoration to room temperature. Images PMID:2846651

  1. A different aspect to use of some soft computing methods for landslide susceptibility mapping

    NASA Astrophysics Data System (ADS)

    Akgün, Aykut

    2014-05-01

    In landslide literature, several applications of soft computing methods such as artifical neural networks (ANN), fuzzy inference systems, and decision trees for landslide susceptibility mapping can be found. In many of these studies, the effectiveness and validation of the models used are also discussed. To carry out analyses, more than one software, for example one statistical package and one geographical information systems software (GIS), are generally used together. In this study, four different soft computing techniques were applied for obtaining landslide susceptibility mapping only by one GIS software. For this purpose, Multi Layer Perceptron (MLP) back propagation neural network, Fuzzy Adaptive Resonance Theory (ARTMAP) neural network, Self-organizing Map (SOM) and Classification Tree Analysis (CTA) approaches were applied to the study area. The study area was selected from a part of Trabzon (North Turkey) city which is one of the most landslide prone areas in Turkey. Initially, five landslide conditioning parameters such as lithology, slope gradient, slope aspect, stream power index (SPI), and topographical wetness index (TWI) for the study area were produced in GIS. Then, these parameters were analysed by MLP, Fuzzy ARTMAP, SOM and CART soft computing classifiers of the IDRISI Taiga GIS and remote sensing software. To accomplish the analyses, two main input groups are needed. These are conditioning parameters and training areas. For training areas, initially, landslide inventory map which was obtained by both field studies and topographical analyses was compared with lithological unit classes. With the help of these comparison, frequency ratio (FR) values of landslide occurrence in the study area were determined. Using the FR values, five landslide susceptibility classes were differentiated from the lowest FR to highest FR values. After this differentiation, the training areas representing the landslide susceptibility classes were determined by using FR

  2. GIS-based assessment of landslide susceptibility using certainty factor and index of entropy models for the Qianyang County of Baoji city, China

    NASA Astrophysics Data System (ADS)

    Wang, Qiqing; Li, Wenping; Chen, Wei; Bai, Hanying

    2015-10-01

    The main goal of this study is to produce landslide susceptibility maps for the Qianyang County of Baoji city, China, using both certainty factor (CF) and index of entropy (IOE) models. At first, a landslide inventory map was prepared using earlier reports and aerial photographs as well as by carrying out field surveys. A total of 81 landslide locations were detected. Out of these, 56 (70%) landslides were randomly selected as training data for building landslide susceptibility models and the remaining 25 (30%) were used for the validation purposes. Then, a total number of 15 landslide causative factors, such as slope angle, slope aspect, general curvature, plan curvature, profile curvature, altitude, distance to faults, distance to rivers, distance to roads, the sediment transport index (STI), the stream power index (SPI), the topographic wetness index (TWI), geomorphology, lithology, and rainfall, were used in the analysis. The susceptibility maps produced using CF and IOE models had five different susceptibility classes such as very low, low, moderate, high, and very high. Finally, the output maps were validated using the validation data (i.e., 30% landslide location data that was not used during the model construction), using the area under the curve (AUC) method. The `success rate' curve showed that the area under the curve for CF and IOE models were 0.8433 (84.33%) and 0.8227 (82.27%) accuracy, respectively. Similarly, the validation result showed that the susceptibility map using CF model has the higher prediction accuracy of 82.32%, while for IOE model it was 80.88%. The results of this study showed that the two landslide susceptibility maps obtained were successful and can be used for preliminary land use planning and hazard mitigation purpose.

  3. Susceptibility testing of anaerobic bacteria: myth, magic, or method?

    PubMed Central

    Wexler, H M

    1991-01-01

    The demand for susceptibility testing of anaerobes has increased, yet consensus as to procedure and interpretation in this area has not been achieved. While routine testing of anaerobic isolates is not needed, certain isolates in specific clinical settings should be tested. Also, laboratories may monitor their local antibiograms by doing periodic surveillance batch testing. The National Committee for Clinical Laboratory Standards has published a protocol of methods approved for susceptibility testing of anaerobic bacteria. Both agar and broth microdilution are included; however, the broth disk elution method is no longer approved by the National Committee for Clinical Laboratory Standards because of method-related interpretive errors. A number of newer methods are undergoing evaluation and seem promising. Clinicians and microbiologists reviewing susceptibility reports should be aware of sources of variability in the test results. Variables in susceptibility testing of anaerobes include the media and methods used, organisms chosen for testing, breakpoints chosen for interpretation, antibiotic, and determination of endpoint. Clustering of MICs around the breakpoint may lead to significant variability in test results. Adherence of testing laboratories to approved methods and careful descriptions of the method and the breakpoints used for interpretation would facilitate interlaboratory comparisons and allow problems of emerging resistance to be noted. A variety of resistance mechanisms occurs in anaerobic bacteria, including the production of beta-lactamase and other drug-inactivating enzymes, alteration of target proteins, and inability of the drug to penetrate the bacterial wall. Antimicrobial resistance patterns in the United States and abroad are described. PMID:1747863

  4. Novel image fusion methods using intuitionistic index

    NASA Astrophysics Data System (ADS)

    Wang, Zirui; Wang, Zhihui

    2015-12-01

    In this paper, we present new methods for image fusion based on intuitionistic index in spatial domain and contourlet transform domain, furthermore we adopt two ways to fuse images in contourlet domain. When constructing an intuitionistic fuzzy set, we use the Gamma function to get the membership degree, and the Sugeno complementation to get the non-membership degree. Based on the information theory, the larger the hesitancy is, the more information it has. So we set up a fusion rule, by which the larger hesitancy will be chosen, to get a fused image from multi-focus images or remote sensing ones. We compare these new algorithms to some classical image fusion algorithms. The results show, for multi-focus image, these new algorithms are better comparing to other algorithms, and they can get a good fusion result, especially the contourlet transformation algorithm using the intuitionistic index. For remote sensing image, these new algorithms are not the best, but they can also get a well fusion result.

  5. Muscle inflammation susceptibility: a prognostic index of recovery potential after hip arthroplasty?

    PubMed

    Bamman, Marcas M; Ferrando, Arny A; Evans, Richard P; Stec, Michael J; Kelly, Neil A; Gruenwald, Johannes M; Corrick, Katie L; Trump, Jesse R; Singh, Jasvinder A

    2015-04-15

    While elective total hip arthroplasty (THA) for end-stage osteoarthritis (OA) improves pain, mobility function, and quality of life in most cases, a large proportion of patients suffer persistent muscle atrophy, pain, and mobility impairment. Extensive skeletal muscle damage is unavoidable in these surgical procedures, and it stands to reason that poor recovery and long-term mobility impairment among some individuals after THA is linked to failed muscle regeneration and regrowth following surgery and that local muscle inflammation susceptibility (MuIS) is a major contributing factor. Here we present results of two integrated studies. In study 1, we compared muscle inflammation and protein metabolism signaling in elective THA (n=15) vs. hip fracture/trauma (HFX; n=11) vs. nonsurgical controls (CON; n=19). In study 2, we compared two subgroups of THA patients dichotomized into MuIS⁺ (n=7) or MuIS⁻ (n=7) based on muscle expression of TNF-like weak inducer of apoptosis (TWEAK) receptor (Fn14). As expected, HFX demonstrated overt systemic and local muscle inflammation and hypermetabolism. By contrast, no systemic inflammation was detected in elective THA patients; however, local muscle inflammation in the perioperative limb was profound in MuIS⁺ and was accompanied by suppressed muscle protein synthesis compared with MuIS⁻. Muscle from the contralateral limb of MuIS⁺ was unaffected, providing evidence of a true inflammation susceptibility localized to the muscle surrounding the hip with end-stage OA. We suggest MuIS status assessed at the time of surgery may be a useful prognostic index for muscle recovery potential and could therefore provide the basis for a personalized approach to postsurgery rehabilitation. PMID:25670829

  6. A probabilistic method for estimating system susceptibility to HPM

    SciTech Connect

    Mensing, R.W.

    1989-05-18

    Interruption of the operation of electronic systems by HPM is a stochastic process. Thus, a realistic estimate of system susceptibility to HPM is best expressed in terms of the probability the HPM have an effect on the system (probability of effect). To estimate susceptibility of complex electronic systems by extensive testing is not practical. Thus, it is necessary to consider alternative approaches. One approach is to combine information from extensive low level testing and computer modeling with limited high level field test data. A method for estimating system susceptibility based on a pretest analysis of low level test and computer model data combined with a post test analysis after high level testing is described in this paper. 4 figs.

  7. Relationship among Probability of Failure, Landslide Susceptibility Index, and Rainfall Parameters

    NASA Astrophysics Data System (ADS)

    Lee, C. T.

    2015-12-01

    Common or basic susceptibility may exist in a region. This common feature has been tested to be true in several drainage basins in Taiwan in recent years. A multi-temporal landslide inventory was commonly used in building a landslide susceptibility model for a region. An event landslide inventory and triggering factors were also used to build an event landslide susceptibility model in recent years. An event-based landslide susceptibility model is dependent on that event, and different event models exhibit different susceptibility pattern. However, if we extract the triggering factors from the event model, then the model would be event-independent and can represent the basic susceptibility of the region. We found that different event-independent susceptibility model for the same region are similar in pattern, and is similar also to a susceptibility model built by a multi-temporal landslide inventory at that region. On this basis, we can use an event-independent susceptibility model to represent the basic susceptibility of the region with confidence. We tested the relationship between probability of failure and rainfall intensity, as well as total rainfall at each basic susceptibility bin. It was found that the relation is good; the probability of failure increases with an increase in the rainfalls and also an increase in the susceptibility. A fitting surface of probability of landslide failure using a rainfall parameter and the basic susceptibility as two independent variables was done and the example will be presented.

  8. A neighborhood susceptibility index for planning of local physical interventions in response to pandemic influenza outbreaks

    PubMed Central

    Timpka, Toomas; Eriksson, Henrik; Strömgren, Magnus; Eriksson, Olle; Ekberg, Joakim; Grimvall, Anders; Nyce, James; Gursky, Elin; Holm, Einar

    2010-01-01

    The global spread of a novel A (H1N1) influenza virus in 2009 has highlighted the possibility of a devastating pandemic similar to the ‘Spanish flu’ of 1917–1918. Responding to such pandemics requires careful planning for the early phases where there is no availability of pandemic vaccine. We set out to compute a Neighborhood Influenza Susceptibility Index (NISI) describing the vulnerability of local communities of different geo-socio-physical structure to a pandemic influenza outbreak. We used a spatially explicit geo-physical model of Linköping municipality (pop. 136,240) in Sweden, and employed an ontology-modeling tool to define simulation models and transmission settings. We found considerable differences in NISI between neighborhoods corresponding to primary care areas with regard to early progress of the outbreak, as well as in terms of the total accumulated share of infected residents counted after the outbreak. The NISI can be used in local preparations of physical response measures during pandemics. PMID:21347087

  9. Coral bleaching response index: a new tool to standardize and compare susceptibility to thermal bleaching.

    PubMed

    Swain, Timothy D; Vega-Perkins, Jesse B; Oestreich, William K; Triebold, Conrad; DuBois, Emily; Henss, Jillian; Baird, Andrew; Siple, Margaret; Backman, Vadim; Marcelino, Luisa

    2016-07-01

    As coral bleaching events become more frequent and intense, our ability to predict and mitigate future events depends upon our capacity to interpret patterns within previous episodes. Responses to thermal stress vary among coral species; however the diversity of coral assemblages, environmental conditions, assessment protocols, and severity criteria applied in the global effort to document bleaching patterns creates challenges for the development of a systemic metric of taxon-specific response. Here, we describe and validate a novel framework to standardize bleaching response records and estimate their measurement uncertainties. Taxon-specific bleaching and mortality records (2036) of 374 coral taxa (during 1982-2006) at 316 sites were standardized to average percent tissue area affected and a taxon-specific bleaching response index (taxon-BRI) was calculated by averaging taxon-specific response over all sites where a taxon was present. Differential bleaching among corals was widely variable (mean taxon-BRI = 25.06 ± 18.44%, ±SE). Coral response may differ because holobionts are biologically different (intrinsic factors), they were exposed to different environmental conditions (extrinsic factors), or inconsistencies in reporting (measurement uncertainty). We found that both extrinsic and intrinsic factors have comparable influence within a given site and event (60% and 40% of bleaching response variance of all records explained, respectively). However, when responses of individual taxa are averaged across sites to obtain taxon-BRI, differential response was primarily driven by intrinsic differences among taxa (65% of taxon-BRI variance explained), not conditions across sites (6% explained), nor measurement uncertainty (29% explained). Thus, taxon-BRI is a robust metric of intrinsic susceptibility of coral taxa. Taxon-BRI provides a broadly applicable framework for standardization and error estimation for disparate historical records and collection of novel

  10. Integration of data-driven and physically-based methods to assess shallow landslides susceptibility

    NASA Astrophysics Data System (ADS)

    Lajas, Sara; Oliveira, Sérgio C.; Zêzere, José Luis

    2016-04-01

    (lithology, land use, slope, aspect, curvature, topographic position index and the slope over area ratio) with the Information Value method and was used also to calibrate the strength parameters (cohesion and friction angle) of the different lithological units considered in the Infinity Slope model; and (ii) the validation group (60 cases) was used to independent validate and define the predictive capacity of the shallow landslides susceptibility maps produced with the Information Value method and the Infinite Slope method. The comparison of both landslide susceptibility maps was supported by: (i) the computation of the Receiver Operator Characteristic (ROC) curves; (ii) the calculation of the Area Under the Curve (AUC); and (iii) the evaluation of the spatial agreement between the landslide susceptibility classes. Finally, the susceptibility maps produced with the Information Value and the Infinite Slope methods are integrated into a single landslide susceptibility map based on a set of integration rules define by cross-validation of the susceptibility classes of both maps and analysis of the corresponding contingency table. This work was supported by the FCT - Portuguese Foundation for Science and Technology and is within the framework of the FORLAND Project. Sérgio Oliveira was funded by a postdoctoral grant (SFRH/BPD/85827/2012) from the Portuguese Foundation for Science and Technology (FCT).

  11. Review of methods to derive a Polar Cap (PC) index.

    NASA Astrophysics Data System (ADS)

    Stauning, Peter

    2016-07-01

    Since a Polar Cap (PC) index was introduced in 1985, several different methods have been used to derive index values. Basically, the northern (PCN) and southern (PCS) are based on geomagnetic recordings at Qaanaaq (Thule) and Vostok, respectively. However, different derivation methods can give index values differing by more than a factor 2. The PC indices are used, among other, in scientific analyses to link solar wind conditions to relevant geophysical effects and in forecast efforts to establish numerical criteria for imminent risk of geomagnetic storms and substorms. Thus, it is unfortunate that several different versions of the PC index have been in use, often without specifically mentioning the index version being used or without ensuring that proper documention and specification of the derivation method is available. The presentation shall briefly describe the basic calculation of a Polar Cap index and point specifically to the differences between the different derivation methods and to the consequences for the index values

  12. Addiction Severity Index Recent and Lifetime Summary Indexes Based on Nonparametric Item Response Theory Methods

    ERIC Educational Resources Information Center

    Alterman, Arthur I.; Cacciola, John S.; Habing, Brian; Lynch, Kevin G.

    2007-01-01

    Baseline Addiction Severity Index (5th ed.; ASI-5) data of 2,142 substance abuse patients were analyzed with two nonparametric item response theory (NIRT) methods: Mokken scaling and conditional covariance techniques. Nine reliable and dimensionally homogeneous Recent Problem indexes emerged in the ASI-5's seven areas, including two each in the…

  13. A comparison of bivariate statistical model and deterministic model-based landslide susceptibility mapping methods: An example from North Turkey

    NASA Astrophysics Data System (ADS)

    Akgun, Aykut; Erkan, Oguzhan

    2015-04-01

    In Turkey, landslide is one of the most important natural hazards. Due to landslide occurrence, several landforms and man made structures are adversely affected, and may cause many injuries and loss of life. In this context, landslide susceptibility assessment is important task to determine susceptible areas to landslide occurrence. Especially, several dam reservoir areas in Turkey are threated by landslide phenomena. For this reason, in this study, a dam reservoir area located in North Turkey was selected, and investigated in point of landslide susceptibility assessment. A landslide susceptibility assessment for the Kurtun dam reservoir area (Gumushane, North Turkey) was carried out by geographical information systems (GIS)-based statistical and deterministic models. For this purpose, frequency ratio (FR) and stability index mapping (SINMAP) methodologies were applied. In this context, eight conditioning parameters such as altitude, lithology, slope gradient, slope aspect, distance to drainage, distance to lineament, stream power index (SPI) and topographical wetness index (TWI) were considered. After assessment of these parameters by FR and SINMAP methods in a GIS environment, two landslide susceptibility maps were obtained. Then, the maps obtained were analyzed for verification purpose. For this purpose, area under curvature (AUC) approach was used. At the end of this process, the AUC values of 0.73 and 0.70 were found for FR and SINMAP methods, respectively. Additionally, the SINMAP statistical results showed that the 93.8% of the observed landslides in the area falls into the lower and upper threshold showing the stability index classes. These values indicate that the accuracies of landslide susceptibility maps are acceptable, and the maps are feasible for further natural hazard management affairs in the area.

  14. Quantitative assessment of susceptibility weighted imaging processing methods

    PubMed Central

    Li, Ningzhi; Wang, Wen-Tung; Sati, Pascal; Pham, Dzung L.; Butman, John A.

    2013-01-01

    Purpose To evaluate different susceptibility weighted imaging (SWI) phase processing methods and parameter selection, thereby improving understanding of potential artifacts, as well as facilitating choice of methodology in clinical settings. Materials and Methods Two major phase processing methods, Homodyne-filtering and phase unwrapping-high pass (HP) filtering, were investigated with various phase unwrapping approaches, filter sizes, and filter types. Magnitude and phase images were acquired from a healthy subject and brain injury patients on a 3T clinical Siemens MRI system. Results were evaluated based on image contrast to noise ratio and presence of processing artifacts. Results When using a relatively small filter size (32 pixels for the matrix size 512 × 512 pixels), all Homodyne-filtering methods were subject to phase errors leading to 2% to 3% masked brain area in lower and middle axial slices. All phase unwrapping-filtering/smoothing approaches demonstrated fewer phase errors and artifacts compared to the Homodyne-filtering approaches. For performing phase unwrapping, Fourier-based methods, although less accurate, were 2–4 orders of magnitude faster than the PRELUDE, Goldstein and Quality-guide methods. Conclusion Although Homodyne-filtering approaches are faster and more straightforward, phase unwrapping followed by HP filtering approaches perform more accurately in a wider variety of acquisition scenarios. PMID:24923594

  15. Genome-wide association analysis identifies three new susceptibility loci for childhood body mass index.

    PubMed

    Felix, Janine F; Bradfield, Jonathan P; Monnereau, Claire; van der Valk, Ralf J P; Stergiakouli, Evie; Chesi, Alessandra; Gaillard, Romy; Feenstra, Bjarke; Thiering, Elisabeth; Kreiner-Møller, Eskil; Mahajan, Anubha; Pitkänen, Niina; Joro, Raimo; Cavadino, Alana; Huikari, Ville; Franks, Steve; Groen-Blokhuis, Maria M; Cousminer, Diana L; Marsh, Julie A; Lehtimäki, Terho; Curtin, John A; Vioque, Jesus; Ahluwalia, Tarunveer S; Myhre, Ronny; Price, Thomas S; Vilor-Tejedor, Natalia; Yengo, Loïc; Grarup, Niels; Ntalla, Ioanna; Ang, Wei; Atalay, Mustafa; Bisgaard, Hans; Blakemore, Alexandra I; Bonnefond, Amelie; Carstensen, Lisbeth; Eriksson, Johan; Flexeder, Claudia; Franke, Lude; Geller, Frank; Geserick, Mandy; Hartikainen, Anna-Liisa; Haworth, Claire M A; Hirschhorn, Joel N; Hofman, Albert; Holm, Jens-Christian; Horikoshi, Momoko; Hottenga, Jouke Jan; Huang, Jinyan; Kadarmideen, Haja N; Kähönen, Mika; Kiess, Wieland; Lakka, Hanna-Maaria; Lakka, Timo A; Lewin, Alexandra M; Liang, Liming; Lyytikäinen, Leo-Pekka; Ma, Baoshan; Magnus, Per; McCormack, Shana E; McMahon, George; Mentch, Frank D; Middeldorp, Christel M; Murray, Clare S; Pahkala, Katja; Pers, Tune H; Pfäffle, Roland; Postma, Dirkje S; Power, Christine; Simpson, Angela; Sengpiel, Verena; Tiesler, Carla M T; Torrent, Maties; Uitterlinden, André G; van Meurs, Joyce B; Vinding, Rebecca; Waage, Johannes; Wardle, Jane; Zeggini, Eleftheria; Zemel, Babette S; Dedoussis, George V; Pedersen, Oluf; Froguel, Philippe; Sunyer, Jordi; Plomin, Robert; Jacobsson, Bo; Hansen, Torben; Gonzalez, Juan R; Custovic, Adnan; Raitakari, Olli T; Pennell, Craig E; Widén, Elisabeth; Boomsma, Dorret I; Koppelman, Gerard H; Sebert, Sylvain; Järvelin, Marjo-Riitta; Hyppönen, Elina; McCarthy, Mark I; Lindi, Virpi; Harri, Niinikoski; Körner, Antje; Bønnelykke, Klaus; Heinrich, Joachim; Melbye, Mads; Rivadeneira, Fernando; Hakonarson, Hakon; Ring, Susan M; Smith, George Davey; Sørensen, Thorkild I A; Timpson, Nicholas J; Grant, Struan F A; Jaddoe, Vincent W V

    2016-01-15

    A large number of genetic loci are associated with adult body mass index. However, the genetics of childhood body mass index are largely unknown. We performed a meta-analysis of genome-wide association studies of childhood body mass index, using sex- and age-adjusted standard deviation scores. We included 35 668 children from 20 studies in the discovery phase and 11 873 children from 13 studies in the replication phase. In total, 15 loci reached genome-wide significance (P-value < 5 × 10(-8)) in the joint discovery and replication analysis, of which 12 are previously identified loci in or close to ADCY3, GNPDA2, TMEM18, SEC16B, FAIM2, FTO, TFAP2B, TNNI3K, MC4R, GPR61, LMX1B and OLFM4 associated with adult body mass index or childhood obesity. We identified three novel loci: rs13253111 near ELP3, rs8092503 near RAB27B and rs13387838 near ADAM23. Per additional risk allele, body mass index increased 0.04 Standard Deviation Score (SDS) [Standard Error (SE) 0.007], 0.05 SDS (SE 0.008) and 0.14 SDS (SE 0.025), for rs13253111, rs8092503 and rs13387838, respectively. A genetic risk score combining all 15 SNPs showed that each additional average risk allele was associated with a 0.073 SDS (SE 0.011, P-value = 3.12 × 10(-10)) increase in childhood body mass index in a population of 1955 children. This risk score explained 2% of the variance in childhood body mass index. This study highlights the shared genetic background between childhood and adult body mass index and adds three novel loci. These loci likely represent age-related differences in strength of the associations with body mass index. PMID:26604143

  16. Generalized nonlinear Schrödinger equation for dispersive susceptibility and permeability: application to negative index materials.

    PubMed

    Scalora, Michael; Syrchin, Maxim S; Akozbek, Neset; Poliakov, Evgeni Y; D'Aguanno, Giuseppe; Mattiucci, Nadia; Bloemer, Mark J; Zheltikov, Aleksei M

    2005-07-01

    A new generalized nonlinear Schrödinger equation describing the propagation of ultrashort pulses in bulk media exhibiting frequency dependent dielectric susceptibility and magnetic permeability is derived and used to characterize wave propagation in a negative index material. The equation has new features that are distinct from ordinary materials (mu=1): the linear and nonlinear coefficients can be tailored through the linear properties of the medium to attain any combination of signs unachievable in ordinary matter, with significant potential to realize a wide class of solitary waves. PMID:16090616

  17. New methods for indexing multi-lattice diffraction data

    SciTech Connect

    Gildea, Richard J.; Waterman, David G.; Parkhurst, James M.; Axford, Danny; Sutton, Geoff; Stuart, David I.; Sauter, Nicholas K.; Evans, Gwyndaf; Winter, Graeme

    2014-10-01

    A new indexing method is presented which is capable of indexing multiple crystal lattices from narrow wedges of data. The efficacy of this method is demonstrated with both semi-synthetic multi-lattice data and real multi-lattice data recorded from microcrystals of ∼1 µm in size. A new indexing method is presented which is capable of indexing multiple crystal lattices from narrow wedges of diffraction data. The method takes advantage of a simplification of Fourier transform-based methods that is applicable when the unit-cell dimensions are known a priori. The efficacy of this method is demonstrated with both semi-synthetic multi-lattice data and real multi-lattice data recorded from crystals of ∼1 µm in size, where it is shown that up to six lattices can be successfully indexed and subsequently integrated from a 1° wedge of data. Analysis is presented which shows that improvements in data-quality indicators can be obtained through accurate identification and rejection of overlapping reflections prior to scaling.

  18. Using a Lethality Index to Assess Susceptibility of Tribolium confusum and Oryzaephilus surinamensis to Insecticides

    PubMed Central

    Vlontzos, George; Arthur, Frank H.

    2015-01-01

    We evaluated knockdown caused by four insecticides: alpha-cypermethrin, chlorfenapyr, pirimiphos-methyl and fipronil against adults of Tribolium confusum Jacquelin Duval, the confused flour beetle and Oryzaephilus surinamensis (L.), the sawtoothed grain beetle. Bioassays were conducted on concrete and metal surfaces. Adults of the tested species were exposed on both surfaces treated with the above insecticides at two doses (low and high). Knockdown assessment was done after 15, 30 and 60 min of adult exposure in the treated surfaces. Also, after 1, 3, 5, 7 and 14 d of exposure, a lethality index was calculated with an equation resulting to values from 0 to 100, where 100 indicated complete mortality and 0 complete survival. We also developed a lethality index by ranking each adult on each surface from 0 to 4, 0: adults moved normally, 1: adults were knocked down, but were able to walk for short intervals, 2: adults were knocked down and unable to walk, but with visible movement of antennae etc., 3: adults were knocked down, with very minimal movement of the tarsi and the antennae and 4: adults were dead (no movement). Knockdown of adults immediately after exposure (15–60 min) was higher for pirimiphos-methyl followed by alpha-cypermethrin, for both dose rates tested and species, but only on the metal surface. The lethality index was nearly 100 for all insecticides after 5d of exposure for O. surinamensis, while for T. confusum the adult lethality index was considerably lower for alpha-cypermethrin, suggesting that that recovery from knockdown occurred. Chlorfenapyr was the only insecticide that was more effective on concrete than on metal, while the reverse was noted for the other three insecticides. These results show that knockdown has different levels, which can be used as indicators of insect mortality or recovery. PMID:26560316

  19. New methods for indexing multi-lattice diffraction data

    DOE PAGESBeta

    Gildea, Richard J.; Waterman, David G.; Parkhurst, James M.; Axford, Danny; Sutton, Geoff; Stuart, David I.; Sauter, Nicholas K.; Evans, Gwyndaf; Winter, Graeme

    2014-09-27

    A new indexing method is presented which is capable of indexing multiple crystal lattices from narrow wedges of diffraction data. The method takes advantage of a simplification of Fourier transform-based methods that is applicable when the unit-cell dimensions are known a priori. The efficacy of this method is demonstrated with both semi-synthetic multi-lattice data and real multi-lattice data recorded from crystals of ~1 µm in size, where it is shown that up to six lattices can be successfully indexed and subsequently integrated from a 1° wedge of data. Analysis is presented which shows that improvements in data-quality indicators can bemore » obtained through accurate identification and rejection of overlapping reflections prior to scaling.« less

  20. New methods for indexing multi-lattice diffraction data

    SciTech Connect

    Gildea, Richard J.; Waterman, David G.; Parkhurst, James M.; Axford, Danny; Sutton, Geoff; Stuart, David I.; Sauter, Nicholas K.; Evans, Gwyndaf; Winter, Graeme

    2014-09-27

    A new indexing method is presented which is capable of indexing multiple crystal lattices from narrow wedges of diffraction data. The method takes advantage of a simplification of Fourier transform-based methods that is applicable when the unit-cell dimensions are known a priori. The efficacy of this method is demonstrated with both semi-synthetic multi-lattice data and real multi-lattice data recorded from crystals of ~1 µm in size, where it is shown that up to six lattices can be successfully indexed and subsequently integrated from a 1° wedge of data. Analysis is presented which shows that improvements in data-quality indicators can be obtained through accurate identification and rejection of overlapping reflections prior to scaling.

  1. New methods for indexing multi-lattice diffraction data

    PubMed Central

    Gildea, Richard J.; Waterman, David G.; Parkhurst, James M.; Axford, Danny; Sutton, Geoff; Stuart, David I.; Sauter, Nicholas K.; Evans, Gwyndaf; Winter, Graeme

    2014-01-01

    A new indexing method is presented which is capable of indexing multiple crystal lattices from narrow wedges of diffraction data. The method takes advantage of a simplification of Fourier transform-based methods that is applicable when the unit-cell dimensions are known a priori. The efficacy of this method is demonstrated with both semi-synthetic multi-lattice data and real multi-lattice data recorded from crystals of ∼1 µm in size, where it is shown that up to six lattices can be successfully indexed and subsequently integrated from a 1° wedge of data. Analysis is presented which shows that improvements in data-quality indicators can be obtained through accurate identification and rejection of overlapping reflections prior to scaling. PMID:25286849

  2. A Simple Method to Estimate Harvest Index in Grain Crops

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Several methods have been proposed to simulate yield in crop simulation models. In this work we present a simple method to estimate harvest index (HI) of grain crops based on fractional post-anthesis growth (fG = fraction of growth that occurred post-anthesis). We propose that there is a linear or c...

  3. Development of a Susceptibility Index of Apple Cultivars for Codling Moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae) Oviposition

    PubMed Central

    Joshi, Neelendra K.; Rajotte, Edwin G.; Myers, Clayton T.; Krawczyk, Greg; Hull, Larry A.

    2015-01-01

    Codling moth (CM), Cydia pomonella (L.) (Lepidoptera: Tortricidae) is a major fruit feeding pest of apples. Understanding susceptibility differences of various apple cultivars to CM oviposition is an important step in developing resistant varieties as well as monitoring and management strategies for this pest in apple orchards planted with mixed-cultivars. In this context, oviposition preferences of CM for the fruits of different apple cultivars were studied in laboratory bioassays using a series of no-choice and multiple-choice tests in 2006, 2007, and 2008. In 2006 and 2007, 10 apple cultivars, viz., Arlet, Fuji, Gala, Golden Delicious, Honeycrisp, Pristine, Delicious, Stayman, Sunrise, and York Imperial were evaluated, while in the 2008 tests, Golden Delicious, Honeycrisp, and York Imperial were evaluated. During the 2006 tests, preferred apple cultivars for CM oviposition were Golden Delicious and Fuji, while the least preferred were Arlet, Pristine, Sunrise, and Honeycrisp. Similarly, during the 2007 tests, Golden Delicious, Fuji and Stayman remained the preferred cultivars, while Arlet, Honeycrisp, Pristine, and Sunrise remained the least preferred cultivars. In the 2008 tests, Golden Delicious and Honeycrisp were the most and least preferred cultivars, respectively. Based on the oviposition preferences from these bioassays, a susceptibility index for each cultivar was developed. This index may be used as a standard measure in cultivar evaluations in breeding programs, and may assist fruit growers and crop consultants to select the most appropriate cultivar(s) for monitoring and detecting the initial signs of fruit injury from CM in an apple orchard planted with mixed-cultivars. PMID:26617629

  4. A Safety Index and Method for Flightdeck Evaluation

    NASA Technical Reports Server (NTRS)

    Latorella, Kara A.

    2000-01-01

    If our goal is to improve safety through machine, interface, and training design, then we must define a metric of flightdeck safety that is usable in the design process. Current measures associated with our notions of "good" pilot performance and ultimate safety of flightdeck performance fail to provide an adequate index of safe flightdeck performance for design evaluation purposes. The goal of this research effort is to devise a safety index and method that allows us to evaluate flightdeck performance holistically and in a naturalistic experiment. This paper uses Reason's model of accident causation (1990) as a basis for measuring safety, and proposes a relational database system and method for 1) defining a safety index of flightdeck performance, and 2) evaluating the "safety" afforded by flightdeck performance for the purpose of design iteration. Methodological considerations, limitations, and benefits are discussed as well as extensions to this work.

  5. Mode-Stirred Method Implementation for HIRF Susceptibility Testing and Results Comparison with Anechoic Method

    NASA Technical Reports Server (NTRS)

    Nguyen, Truong X.; Ely, Jay J.; Koppen, Sandra V.

    2001-01-01

    This paper describes the implementation of mode-stirred method for susceptibility testing according to the current DO-160D standard. Test results on an Engine Data Processor using the implemented procedure and the comparisons with the standard anechoic test results are presented. The comparison experimentally shows that the susceptibility thresholds found in mode-stirred method are consistently higher than anechoic. This is consistent with the recent statistical analysis finding by NIST that the current calibration procedure overstates field strength by a fixed amount. Once the test results are adjusted for this value, the comparisons with the anechoic results are excellent. The results also show that test method has excellent chamber to chamber repeatability. Several areas for improvements to the current procedure are also identified and implemented.

  6. A Molecular Selection Index Method Based on Eigenanalysis

    PubMed Central

    Cerón-Rojas, J. Jesús; Castillo-González, Fernando; Sahagún-Castellanos, Jaime; Santacruz-Varela, Amalio; Benítez-Riquelme, Ignacio; Crossa, José

    2008-01-01

    The traditional molecular selection index (MSI) employed in marker-assisted selection maximizes the selection response by combining information on molecular markers linked to quantitative trait loci (QTL) and phenotypic values of the traits of the individuals of interest. This study proposes an MSI based on an eigenanalysis method (molecular eigen selection index method, MESIM), where the first eigenvector is used as a selection index criterion, and its elements determine the proportion of the trait's contribution to the selection index. This article develops the theoretical framework of MESIM. Simulation results show that the genotypic means and the expected selection response from MESIM for each trait are equal to or greater than those from the traditional MSI. When several traits are simultaneously selected, MESIM performs well for traits with relatively low heritability. The main advantages of MESIM over the traditional molecular selection index are that its statistical sampling properties are known and that it does not require economic weights and thus can be used in practical applications when all or some of the traits need to be improved simultaneously. PMID:18716338

  7. Method and system for efficiently searching an encoded vector index

    DOEpatents

    Bui, Thuan Quang; Egan, Randy Lynn; Kathmann, Kevin James

    2001-09-04

    Method and system aspects for efficiently searching an encoded vector index are provided. The aspects include the translation of a search query into a candidate bitmap, and the mapping of data from the candidate bitmap into a search result bitmap according to entry values in the encoded vector index. Further, the translation includes the setting of a bit in the candidate bitmap for each entry in a symbol table that corresponds to candidate of the search query. Also included in the mapping is the identification of a bit value in the candidate bitmap pointed to by an entry in an encoded vector.

  8. A multiresolution method for tagline detection and indexing.

    PubMed

    Yuan, Xiaohui; Zhang, Jian; Buckles, Bill P

    2010-03-01

    Tagline detection and indexing are challenging tasks due to complicated anatomical properties and imaging noise. In this paper, we will address the following two important issues in tagline detection: 1) an automatic method independent from imaging approaches with improved robustness and accuracy and 2) tagline indexing that matches taglines in task and reference images for postprocessing. Our method consists of two steps: First, a wavelet decomposition is performed on a tagged magnetic resonance (tMR) image. Subband correlation is used to dampen anatomical boundaries but enhance taglines. A tagline map is created by segmenting a reconstructed image using pseudowavelet reconstruction. Next, tagline pixels are grouped into clusters and isolated small line segments are eliminated. A snake method is then used to index and recover broken taglines. Our method has been validated with 320 tMR tongue images. Measurement of tagline accuracy was performed by computing tag pixel displacement. Without assumptions on tagline models, it detects taglines automatically. Comparison studies were conducted against the harmonic phase method. Our experiments resulted in a p-value of 1E-6 with one-way ANOVA, which indicates a significant improvement in accuracy and robustness. PMID:20129871

  9. A reproducible method to determine the meteoroid mass index

    NASA Astrophysics Data System (ADS)

    Pokorný, P.; Brown, P. G.

    2016-08-01

    Context. The determination of meteoroid mass indices is central to flux measurements and evolutionary studies of meteoroid populations. However, different authors use different approaches to fit observed data, making results difficult to reproduce and the resulting uncertainties difficult to justify. The real, physical, uncertainties are usually an order of magnitude higher than the reported values. Aims: We aim to develop a fully automated method that will measure meteoroid mass indices and associated uncertainty. We validate our method on large radar and optical datasets and compare results to obtain a best estimate of the true meteoroid mass index. Methods: Using MultiNest, a Bayesian inference tool that calculates the evidence and explores the parameter space, we search for the best fit of cumulative number vs. mass distributions in a four-dimensional space of variables (a,b,X1,X2). We explore biases in meteor echo distributions using optical meteor data as a calibration dataset to establish the systematic offset in measured mass index values. Results: Our best estimate for the average de-biased mass index for the sporadic meteoroid complex, as measured by radar appropriate to the mass range 10-3 > m > 10-5 g, was s = -2.10 ± 0.08. Optical data in the 10-1 > m > 10-3 g range, with the shower meteors removed, produced s = -2.08 ± 0.08. We find the mass index used by Grün et al. (1985) is substantially larger than we measure in the 10-4 < m < 10-1 g range. Our own code with a simple manual and a sample dataset can be found here: http://ftp://aquarid.physics.uwo.ca/pub/peter/MassIndexCode/

  10. Methicillin Resistant Staphylococcus aureus: Inconsistencies in Vancomycin Susceptibility Testing Methods, Limitations and Advantages of each Method

    PubMed Central

    Himani; Madan, Molly; Pandey, Anita; Thakuria, Bhaskar

    2015-01-01

    Background Vancomycin may be ineffective against an increasing proportion of methicillin resistant Staphylococcus aureus (MRSA) with minimum inhibitory concentrations (MICs) well within the susceptible range. On the other hand it is common knowledge that determination of vancomycin MICs is method dependent. Therefore, given the apparent variability in vancomycin MIC results obtained with the different methods, the use of the vancomycin MIC to predict the outcome of serious S. aureus infections needs to take into account the method used and the results of studies using that particular method. Aim Comparative study was carried out to evaluate the MICs obtained by BMD method, E-test, and Vitek 2 method and to detect inconsistencies in these vancomycin for 66 MRSA isolates obtained from various samples of patients attending the OPDs & IPDs within a period of one year. Materials and Methods A comparative study was carried out to evaluate the MICs obtained by BMD method, E-test, and Vitek 2 method to detect vancomycin susceptibility in 66 clinical isolates of MRSA obtained from various samples of patients attending the OPDs & IPDs within a period of one year. The study was conducted in Department of Microbiology, Subharti Medical College, Meerut from January to December 2012. Results On determination of MICs for vancomycin for the MRSA isolates, all were identified as VSSA by BMD, E-Test & Vitek 2 methods. However, the vancomycin MIC values obtained by E-test correlated better with BMD method (correlation factor= 0.6727) than Vitek 2 (correlation factor=0.5316), indicating E-Test to be a better method for determination of vancomycin MICs as compared to Vitek 2. Conclusion MRSA isolates with higher vancomycin MICs, even within the susceptibility range, are being observed more frequently which result in treatment failures with vancomycin. Because of the discrepancy that exists in vancomycin MIC results from different methods, the prediction of outcome of serious S

  11. A method in model updating using Miscorrelation Index sensitivity

    NASA Astrophysics Data System (ADS)

    Kozak, Mustafa Tuğrul; Öztürk, Murat; Özgüven, H. Nevzat

    2009-08-01

    This paper presents a new model updating method based on minimization of an index called Miscorrelation Index (MCI), which is introduced to localize the coordinates carrying error in a finite element (FE) model. MCI can be calculated from measured frequency response functions (FRFs) and dynamic stiffness matrix of the FE model for each coordinate as a function of frequency. Nonzero numerical values for MCI of a coordinate indicate errors in one or more elements of the system matrices corresponding to this coordinate. The sensitivity-driven model updating method presented in this study (MCI Sensitivity Method) is based on minimization of MCI. The application of the method is illustrated with four case studies. In the first and second examples a discrete system is considered, and computationally generated and polluted FRFs are used as pseudo-test data. In the third and fourth case studies, real test data is used and the performance of the method in practical applications is demonstrated on the benchmark structure built to simulate the dynamic behavior of an airplane, namely, GARTEUR SM-AG19 test bed. It is concluded that MCI Sensitivity Method yields successful results even when the measured responses of only a few coordinates are used, especially when miscorrelation is due to local errors.

  12. Zero-velocity magnetophoretic method for the determination of particle magnetic susceptibility.

    PubMed

    Watarai, Hitoshi; Duc, Hoang Trong Tien; Lan, Tran Thi Ngoc; Zhang, Tianyi; Tsukahara, Satoshi

    2014-01-01

    A simple zero-velocity method to determine the particle magnetic susceptibility by measuring the magnetophoretic velocity was proposed. The principle is that the magnetophoretic velocity of a particle in a liquid medium must be zero when the magnetic susceptibilities of the medium and the particle are equal, or the gravity force and the magnetophoretic force are balanced. By changing the medium magnetic susceptibility and measuring the magnetophoretic velocity of a particle, the particle magnetic susceptibility was determined from the medium magnetic susceptibility under the zero-velocity condition. The feasibility of the method was demonstrated for polystyrene particles using a Dy(III) solution in the horizontal migration mode and different organic solvents in the vertical migration mode. PMID:25007934

  13. A Simple Method to Determine the Refractive Index of Glass.

    ERIC Educational Resources Information Center

    Mak, Se-yuen

    1988-01-01

    Describes an experiment for determining the refractive index. Discusses the experiment procedure and mathematical expression for calculating the index. Provides two geometrical diagrams and a graph for determining the index with a typical data. (YP)

  14. The lead-lag relationship between stock index and stock index futures: A thermal optimal path method

    NASA Astrophysics Data System (ADS)

    Gong, Chen-Chen; Ji, Shen-Dan; Su, Li-Ling; Li, Sai-Ping; Ren, Fei

    2016-02-01

    The study of lead-lag relationship between stock index and stock index futures is of great importance for its wide application in hedging and portfolio investments. Previous works mainly use conventional methods like Granger causality test, GARCH model and error correction model, and focus on the causality relation between the index and futures in a certain period. By using a non-parametric approach-thermal optimal path (TOP) method, we study the lead-lag relationship between China Securities Index 300 (CSI 300), Hang Seng Index (HSI), Standard and Poor 500 (S&P 500) Index and their associated futures to reveal the variance of their relationship over time. Our finding shows evidence of pronounced futures leadership for well established index futures, namely HSI and S&P 500 index futures, while index of developing market like CSI 300 has pronounced leadership. We offer an explanation based on the measure of an indicator which quantifies the differences between spot and futures prices for the surge of lead-lag function. Our results provide new perspectives for the understanding of the dynamical evolution of lead-lag relationship between stock index and stock index futures, which is valuable for the study of market efficiency and its applications.

  15. Isolation Method (direct plating or enrichment) does not affect Antimicrobial Susceptibility of Campylobacter from Chicken Carcasses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To determine if Campylobacter isolation method influenced antimicrobial susceptibility results, the minimum inhibitory concentrations (MIC) of nine antimicrobials were compared for 291 pairs of Campylobacter isolates recovered from chicken carcass rinse samples using direct plating and an enrichment...

  16. BSAC standardized disc susceptibility testing method (version 8).

    PubMed

    Andrews, J M

    2009-09-01

    There have been considerable changes to the format of the recommendations since the previous version (version 7). The majority of the footnotes to the tables have been removed and the notations added to the end column; it is hoped that this change will avoid confusion in interpretation. Antibiotics have been separated into groups, e.g. beta-lactams, aminoglycosides, etc. Recommendations for urinary tract infections (UTIs) have been removed for most agents except for those that are administered solely for the treatment of uncomplicated UTIs or where there are limited recommendations for specific organisms, e.g. trimethoprim. For agents that previously had dual recommendations, systemic recommendations remain and the intermediate category can be used for interpretation for UTIs because intermediate susceptibility infers that the infection may respond as the agent is concentrated at the site of infection. This change will also avoid errors in interpretation when an organism is isolated from multiple sites, e.g. blood and urine. The changes that have been made to version 7 are as follows: MIC and zone diameter breakpoints (BPs) for trimethoprim, fosfomycin and nitrofurantoin for UTIs (Table 7); MIC and zone diameter breakpoints (BPs) for doripenem (Tables 7-9); colistin MIC BPs for Pseudomonas spp. (Table 9), co-trimoxazole MIC BPs for Stenotrophomonas maltophilia (Table 10); staphylococci MIC and zone diameter BPs for clarithromycin, clindamycin, erythromycin, quinupristin/dalfopristin, trimethoprim UTI, nitrofurantoin UTI and rifampicin (Table 11); Streptococcus pneumoniae MIC and zone diameter BPs for azithromycin, clarithromycin, erythromycin, co-trimoxazole, linezolid, rifampicin and telithromycin (Table 12); addition of streptomycin recommendations for enterococci (Table 13); enterococcal MIC and zone diameter BPs for quinupristin/dalfopristin, nitrofurantoin UTI and trimethoprim UTI (Table 13); beta-haemolytic streptococci MIC and zone diameter BPs for

  17. Incidences from modifications of the computational methods of the psophic index

    NASA Technical Reports Server (NTRS)

    Francois, J.

    1981-01-01

    In France, the level of annoyance in areas around airports is represented by the psyphic index N. Various modifications were proposed in the method of calculating this indexing order to improve the index as an annoyance indicator. The quality of the modified N index as a prognosis index for annoyance caused by aircraft noise is included.

  18. Bacterial Cytological Profiling (BCP) as a Rapid and Accurate Antimicrobial Susceptibility Testing Method for Staphylococcus aureus

    PubMed Central

    Quach, D.T.; Sakoulas, G.; Nizet, V.; Pogliano, J.; Pogliano, K.

    2016-01-01

    Successful treatment of bacterial infections requires the timely administration of appropriate antimicrobial therapy. The failure to initiate the correct therapy in a timely fashion results in poor clinical outcomes, longer hospital stays, and higher medical costs. Current approaches to antibiotic susceptibility testing of cultured pathogens have key limitations ranging from long run times to dependence on prior knowledge of genetic mechanisms of resistance. We have developed a rapid antimicrobial susceptibility assay for Staphylococcus aureus based on bacterial cytological profiling (BCP), which uses quantitative fluorescence microscopy to measure antibiotic induced changes in cellular architecture. BCP discriminated between methicillin-susceptible (MSSA) and -resistant (MRSA) clinical isolates of S. aureus (n = 71) within 1–2 h with 100% accuracy. Similarly, BCP correctly distinguished daptomycin susceptible (DS) from daptomycin non-susceptible (DNS) S. aureus strains (n = 20) within 30 min. Among MRSA isolates, BCP further identified two classes of strains that differ in their susceptibility to specific combinations of beta-lactam antibiotics. BCP provides a rapid and flexible alternative to gene-based susceptibility testing methods for S. aureus, and should be readily adaptable to different antibiotics and bacterial species as new mechanisms of resistance or multidrug-resistant pathogens evolve and appear in mainstream clinical practice. PMID:26981574

  19. Bacterial Cytological Profiling (BCP) as a Rapid and Accurate Antimicrobial Susceptibility Testing Method for Staphylococcus aureus.

    PubMed

    Quach, D T; Sakoulas, G; Nizet, V; Pogliano, J; Pogliano, K

    2016-02-01

    Successful treatment of bacterial infections requires the timely administration of appropriate antimicrobial therapy. The failure to initiate the correct therapy in a timely fashion results in poor clinical outcomes, longer hospital stays, and higher medical costs. Current approaches to antibiotic susceptibility testing of cultured pathogens have key limitations ranging from long run times to dependence on prior knowledge of genetic mechanisms of resistance. We have developed a rapid antimicrobial susceptibility assay for Staphylococcus aureus based on bacterial cytological profiling (BCP), which uses quantitative fluorescence microscopy to measure antibiotic induced changes in cellular architecture. BCP discriminated between methicillin-susceptible (MSSA) and -resistant (MRSA) clinical isolates of S. aureus (n = 71) within 1-2 h with 100% accuracy. Similarly, BCP correctly distinguished daptomycin susceptible (DS) from daptomycin non-susceptible (DNS) S. aureus strains (n = 20) within 30 min. Among MRSA isolates, BCP further identified two classes of strains that differ in their susceptibility to specific combinations of beta-lactam antibiotics. BCP provides a rapid and flexible alternative to gene-based susceptibility testing methods for S. aureus, and should be readily adaptable to different antibiotics and bacterial species as new mechanisms of resistance or multidrug-resistant pathogens evolve and appear in mainstream clinical practice. PMID:26981574

  20. A Microfluidic Channel Method for Rapid Drug-Susceptibility Testing of Pseudomonas aeruginosa

    PubMed Central

    Matsumoto, Yoshimi; Grushnikov, Andrey; Kikuchi, Kazuma; Noji, Hiroyuki; Yamaguchi, Akihito; Yagi, Yasushi

    2016-01-01

    The recent global increase in the prevalence of antibiotic-resistant bacteria and lack of development of new therapeutic agents emphasize the importance of selecting appropriate antimicrobials for the treatment of infections. However, to date, the development of completely accelerated drug susceptibility testing methods has not been achieved despite the availability of a rapid identification method. We proposed an innovative rapid method for drug susceptibility testing for Pseudomonas aeruginosa that provides results within 3 h. The drug susceptibility testing microfluidic (DSTM) device was prepared using soft lithography. It consisted of five sets of four microfluidic channels sharing one inlet slot, and the four channels are gathered in a small area, permitting simultaneous microscopic observation. Antimicrobials were pre-introduced into each channel and dried before use. Bacterial suspensions in cation-adjusted Mueller–Hinton broth were introduced from the inlet slot and incubated for 3 h. Susceptibilities were microscopically evaluated on the basis of differences in cell numbers and shapes between drug-treated and control cells, using dedicated software. The results of 101 clinically isolated strains of P. aeruginosa obtained using the DSTM method strongly correlated with results obtained using the ordinary microbroth dilution method. Ciprofloxacin, meropenem, ceftazidime, and piperacillin caused elongation in susceptible cells, while meropenem also induced spheroplast and bulge formation. Morphological observation could alternatively be used to determine the susceptibility of P. aeruginosa to these drugs, although amikacin had little effect on cell shape. The rapid determination of bacterial drug susceptibility using the DSTM method could also be applicable to other pathogenic species, and it could easily be introduced into clinical laboratories without the need for expensive instrumentation. PMID:26872134

  1. A Microfluidic Channel Method for Rapid Drug-Susceptibility Testing of Pseudomonas aeruginosa.

    PubMed

    Matsumoto, Yoshimi; Sakakihara, Shouichi; Grushnikov, Andrey; Kikuchi, Kazuma; Noji, Hiroyuki; Yamaguchi, Akihito; Iino, Ryota; Yagi, Yasushi; Nishino, Kunihiko

    2016-01-01

    The recent global increase in the prevalence of antibiotic-resistant bacteria and lack of development of new therapeutic agents emphasize the importance of selecting appropriate antimicrobials for the treatment of infections. However, to date, the development of completely accelerated drug susceptibility testing methods has not been achieved despite the availability of a rapid identification method. We proposed an innovative rapid method for drug susceptibility testing for Pseudomonas aeruginosa that provides results within 3 h. The drug susceptibility testing microfluidic (DSTM) device was prepared using soft lithography. It consisted of five sets of four microfluidic channels sharing one inlet slot, and the four channels are gathered in a small area, permitting simultaneous microscopic observation. Antimicrobials were pre-introduced into each channel and dried before use. Bacterial suspensions in cation-adjusted Mueller-Hinton broth were introduced from the inlet slot and incubated for 3 h. Susceptibilities were microscopically evaluated on the basis of differences in cell numbers and shapes between drug-treated and control cells, using dedicated software. The results of 101 clinically isolated strains of P. aeruginosa obtained using the DSTM method strongly correlated with results obtained using the ordinary microbroth dilution method. Ciprofloxacin, meropenem, ceftazidime, and piperacillin caused elongation in susceptible cells, while meropenem also induced spheroplast and bulge formation. Morphological observation could alternatively be used to determine the susceptibility of P. aeruginosa to these drugs, although amikacin had little effect on cell shape. The rapid determination of bacterial drug susceptibility using the DSTM method could also be applicable to other pathogenic species, and it could easily be introduced into clinical laboratories without the need for expensive instrumentation. PMID:26872134

  2. In Vitro Antibiotic Susceptibilities of Yersinia pestis Determined by Broth Microdilution following CLSI Methods

    PubMed Central

    Hershfield, Jeremy; Marchand, Charles; Miller, Lynda; Halasohoris, Stephanie; Purcell, Bret K.; Worsham, Patricia L.

    2015-01-01

    In vitro susceptibilities to 45 antibiotics were determined for 30 genetically and geographically diverse strains of Yersinia pestis by the broth microdilution method at two temperatures, 28°C and 35°C, following Clinical and Laboratory Standards Institute (CLSI) methods. The Y. pestis strains demonstrated susceptibility to aminoglycosides, quinolones, tetracyclines, β-lactams, cephalosporins, and carbapenems. Only a 1-well shift was observed for the majority of antibiotics between the two temperatures. Establishing and comparing antibiotic susceptibilities of a diverse but specific set of Y. pestis strains by standardized methods and establishing population ranges and MIC50 and MIC90 values provide reference information for assessing new antibiotic agents and also provide a baseline for use in monitoring any future emergence of resistance. PMID:25583720

  3. Diagnosis of coccidioidomycosis by culture: safety considerations, traditional methods, and susceptibility testing.

    PubMed

    Sutton, Deanna A

    2007-09-01

    The recovery of Coccidioides spp. by culture and confirmation utilizing the AccuProbe nucleic acid hybridization method by GenProbe remain the definitive diagnostic method. Biosafety considerations from specimen collection through culture confirmation in the mycology laboratory are critical, as acquisition of coccidioidomycosis by laboratory workers is well documented. The designation of Coccidioides spp. as select agents of potential bioterrorism has mandated strict regulation of their transport and inventory. The genus appears generally susceptible, in vitro, although no defined breakpoints exist. Susceptibility testing may assist in documenting treatment failures. PMID:17363439

  4. Multicenter evaluation of broth microdilution method for susceptibility testing of Cryptococcus neoformans against fluconazole.

    PubMed Central

    Sanati, H; Messer, S A; Pfaller, M; Witt, M; Larsen, R; Espinel-Ingroff, A; Ghannoum, M

    1996-01-01

    We have developed a microdilution method for measuring the susceptibility of Cryptococcus neoformans to fluconazole. The present study evaluated the interlaboratory agreement of the results for the microdilution method obtained at three different sites and compared this method with the National Committee for Clinical Laboratory Standards M27-P reference method. Excellent interlaboratory agreement among the results obtained at the three sites was achieved with this method (83 and 96% agreement within 1 and 2 log2 dilutions, respectively). An overall agreement of 90% between the microdilution method and the M27-P method was observed, demonstrating the comparability of the two methods. However, there are inherent problems with the M27-P method in relation to measuring C. neoformans susceptibility, including suboptimal growth of the organism in RPMI 1640, a longer incubation period, and a narrow range of MICs. On the basis of these data, the microdilution method tested in this study is recommended for inclusion in the National Committee for Laboratory Standards method for testing the antifungal susceptibility of C. neoformans. PMID:8727919

  5. Comparison of Soil Quality Index Using Three Methods

    PubMed Central

    Mukherjee, Atanu; Lal, Rattan

    2014-01-01

    Assessment of management-induced changes in soil quality is important to sustaining high crop yield. A large diversity of cultivated soils necessitate identification development of an appropriate soil quality index (SQI) based on relative soil properties and crop yield. Whereas numerous attempts have been made to estimate SQI for major soils across the World, there is no standard method established and thus, a strong need exists for developing a user-friendly and credible SQI through comparison of various available methods. Therefore, the objective of this article is to compare three widely used methods to estimate SQI using the data collected from 72 soil samples from three on-farm study sites in Ohio. Additionally, challenge lies in establishing a correlation between crop yield versus SQI calculated either depth wise or in combination of soil layers as standard methodology is not yet available and was not given much attention to date. Predominant soils of the study included one organic (Mc), and two mineral (CrB, Ko) soils. Three methods used to estimate SQI were: (i) simple additive SQI (SQI-1), (ii) weighted additive SQI (SQI-2), and (iii) statistically modeled SQI (SQI-3) based on principal component analysis (PCA). The SQI varied between treatments and soil types and ranged between 0–0.9 (1 being the maximum SQI). In general, SQIs did not significantly differ at depths under any method suggesting that soil quality did not significantly differ for different depths at the studied sites. Additionally, data indicate that SQI-3 was most strongly correlated with crop yield, the correlation coefficient ranged between 0.74–0.78. All three SQIs were significantly correlated (r = 0.92–0.97) to each other and with crop yield (r = 0.65–0.79). Separate analyses by crop variety revealed that correlation was low indicating that some key aspects of soil quality related to crop response are important requirements for estimating SQI. PMID:25148036

  6. A Reference Broth Microdilution Method for Dalbavancin In Vitro Susceptibility Testing of Bacteria that Grow Aerobically.

    PubMed

    Koeth, Laura M; DiFranco-Fisher, Jeanna M; McCurdy, Sandra

    2015-01-01

    Antimicrobial susceptibility testing (AST) is performed to assess the in vitro activity of antimicrobial agents against various bacteria. The AST results, which are expressed as minimum inhibitory concentrations (MICs) are used in research for antimicrobial development and monitoring of resistance development and in the clinical setting for antimicrobial therapy guidance. Dalbavancin is a semi-synthetic lipoglycopeptide antimicrobial agent that was approved in May 2014 by the Food and Drug Administration (FDA) for the treatment of acute bacterial skin and skin structure infections caused by Gram-positive organisms. The advantage of dalbavancin over current anti-staphylococcal therapies is its long half-life, which allows for once-weekly dosing. Dalbavancin has activity against Staphylococcus aureus (including both methicillin-susceptible S. aureus [MSSA] and methicillin-resistant S. aureus [MRSA]), coagulase-negative staphylococci, Streptococcus pneumoniae, Streptococcus anginosus group, β-hemolytic streptococci and vancomycin susceptible enterococci. Similar to other recent lipoglycopeptide agents, optimization of CLSI and ISO broth susceptibility test methods includes the use of dimethyl sulfoxide (DMSO) as a solvent when preparing stock solutions and polysorbate 80 (P80) to alleviate adherence of the agent to plastic. Prior to the clinical studies and during the initial development of dalbavancin, susceptibility studies were not performed with the use of P-80 and MIC results tended to be 2-4 fold higher and similarly higher MIC results were obtained with the agar dilution susceptibility method. Dalbavancin was first included in CLSI broth microdilution methodology tables in 2005 and amended in 2006 to clarify use of DMSO and P-80. The broth microdilution (BMD) procedure shown here is specific to dalbavancin and is in accordance with the CLSI and ISO methods, with step-by-step detail and focus on the critical steps added for clarity. PMID:26381422

  7. Comparison of Three Reference Methods for Testing Susceptibility of Staphylococci to Trimethoprim-Sulfamethoxazole▿

    PubMed Central

    Griffith, R.; Creely, D.; Revell, P.; Dunne, W. Michael; Shortridge, D.

    2009-01-01

    Three reference MIC methods approved by the Clinical and Laboratory Standards Institute were compared by testing 567 staphylococci against trimethoprim-sulfamethoxazole. Category agreement ranged from 94.9% (broth macrodilution versus broth microdilution) to 98.6% (agar dilution versus broth microdilution). Twenty-seven strains resistant by broth macrodilution were susceptible by broth microdilution. PMID:19741069

  8. Method to create gradient index in a polymer

    DOEpatents

    Dirk, Shawn M; Johnson, Ross Stefan; Boye, Robert; Descour, Michael R; Sweatt, William C; Wheeler, David R; Kaehr, Bryan James

    2014-10-14

    Novel photo-writable and thermally switchable polymeric materials exhibit a refractive index change of .DELTA.n.gtoreq.1.0 when exposed to UV light or heat. For example, lithography can be used to convert a non-conjugated precursor polymer to a conjugated polymer having a higher index-of-refraction. Further, two-photon lithography can be used to pattern high-spatial frequency structures.

  9. Comparison of Four Methods for Determining Lysostaphin Susceptibility of Various Strains of Staphylococcus aureus

    PubMed Central

    Kusuma, Caroline M.; Kokai-Kun, John F.

    2005-01-01

    Lysostaphin is an endopeptidase that cleaves the pentaglycine cross-bridges of the staphylococcal cell wall rapidly lysing the bacteria. Recently, lysostaphin has been examined for its potential to treat infections and to clear Staphylococcus aureus nasal colonization, requiring a reliable method for determining the lysostaphin susceptibility of strains of S. aureus. We compared four methods for determining the lysostaphin susceptibility of 57 strains of methicillin-sensitive S. aureus, methicillin-resistant S. aureus, vancomycin intermediately susceptible S. aureus (VISA), mupirocin-resistant S. aureus, and various defined genetic mutants of S. aureus. Three reference lysostaphin-resistant S. aureus variants were also included in the assays as negative controls. The assays examined included turbidity, MIC, minimum bactericidal concentration (MBC), and disk diffusion assays. All of the strains of S. aureus tested, including a VISA strain which had previously been reported to be lysostaphin resistant, were susceptible to lysostaphin by all four methods. The three reference lysostaphin-resistant variants were resistant by all four methods. The disk diffusion assay was the simplest method to differentiate lysostaphin-susceptible S. aureus strains from lysostaphin-resistant variants, while the MBC assay could be used as a follow-up assay if required. In the disk diffusion assay, all strains of S. aureus tested revealed zones of inhibition of ≥11 mm using a 50-μg lysostaphin disk, while the three reference lysostaphin-resistant S. aureus variants had no zones of inhibition. In MBC assays, concentrations of lysostaphin ranging from 0.16 μg/ml to 2.5 μg/ml were found to cause a 3 log or greater drop from the initial CFU of S. aureus within 30 min for all strains tested. PMID:16048934

  10. Methods for semi-automated indexing for high precision information retrieval

    NASA Technical Reports Server (NTRS)

    Berrios, Daniel C.; Cucina, Russell J.; Fagan, Lawrence M.

    2002-01-01

    OBJECTIVE: To evaluate a new system, ISAID (Internet-based Semi-automated Indexing of Documents), and to generate textbook indexes that are more detailed and more useful to readers. DESIGN: Pilot evaluation: simple, nonrandomized trial comparing ISAID with manual indexing methods. Methods evaluation: randomized, cross-over trial comparing three versions of ISAID and usability survey. PARTICIPANTS: Pilot evaluation: two physicians. Methods evaluation: twelve physicians, each of whom used three different versions of the system for a total of 36 indexing sessions. MEASUREMENTS: Total index term tuples generated per document per minute (TPM), with and without adjustment for concordance with other subjects; inter-indexer consistency; ratings of the usability of the ISAID indexing system. RESULTS: Compared with manual methods, ISAID decreased indexing times greatly. Using three versions of ISAID, inter-indexer consistency ranged from 15% to 65% with a mean of 41%, 31%, and 40% for each of three documents. Subjects using the full version of ISAID were faster (average TPM: 5.6) and had higher rates of concordant index generation. There were substantial learning effects, despite our use of a training/run-in phase. Subjects using the full version of ISAID were much faster by the third indexing session (average TPM: 9.1). There was a statistically significant increase in three-subject concordant indexing rate using the full version of ISAID during the second indexing session (p < 0.05). SUMMARY: Users of the ISAID indexing system create complex, precise, and accurate indexing for full-text documents much faster than users of manual methods. Furthermore, the natural language processing methods that ISAID uses to suggest indexes contributes substantially to increased indexing speed and accuracy.

  11. Use of a proposed antimicrobial susceptibility testing method for Haemophilus parasuis.

    PubMed

    Dayao, Denise Ann E; Kienzle, Marco; Gibson, Justine S; Blackall, Patrick J; Turni, Conny

    2014-08-27

    The aim of this study was to examine the antimicrobial susceptibility of 97 Haemophilus parasuis cultured from Australian pigs. As there is no existing standard antimicrobial susceptibility technique available for H. parasuis, methods utilising the supplemented media, BA/SN for disc diffusion and test medium broth (TMB) for a microdilution technique, were initially evaluated with the reference strains recommended by the Clinical and Laboratory Standards Institute. The results of the media evaluation suggested that BA/SN and TMB can be used as suitable media for susceptibility testing of H. parasuis. The proposed microdilution technique was then used with 97 H. parasuis isolates and nine antimicrobial agents. The study found that Australian isolates showed elevated minimum inhibitory concentrations (MICs) for ampicillin (1%), penicillin (2%), erythromycin (7%), tulathromycin (9%), tilmicosin (22%), tetracycline (31%) and trimethoprim-sulfamethoxazole (40%). This study has described potential antimicrobial susceptibility methods for H. parasuis and has detected a low percentage of Australian H. parasuis isolates with elevated antimicrobial MICs. PMID:24984947

  12. Antimicrobial susceptibility testing of Australian isolates of Brachyspira hyodysenteriae using a new broth dilution method.

    PubMed

    Karlsson, Märit; Oxberry, Sophy L; Hampson, David J

    2002-01-01

    The antimicrobial susceptibilities of 76 field isolates of Brachyspira hyodysenteriae from different states of Australia were tested in a newly developed broth dilution procedure. The antimicrobial agents used were tiamulin, valnemulin, tylosin, erythromycin, lincomycin and clindamycin. The results from the broth dilution susceptibility testing of 39 of the isolates were compared with results obtained for the same isolates using the agar dilution method. Amongst the isolates tested by broth dilution, 17 were from three farms and had been collected over a number of years. Their pulsed field gel electrophoresis pattern previously had been determined. The broth dilution technique was simple to use, less labor intensive than agar dilution, and gave clear end points. The results obtained using the two methods generally corresponded well, although in a few cases the MIC obtained by broth dilution were lower than those with agar dilution. For the 76 isolates tested by broth dilution, the MIC(90) (mg/l) was: tiamulin, 1; valnemulin, 0.5; tylosin>256; erythromycin>256; lincomycin, 64 and clindamycin, 16. Only minor differences in susceptibility patterns were found amongst isolates from different Australian states. Over all the isolates, and also amongst the isolates obtained from different years on the three farms, there was no trend for the susceptibility of the isolates to alter with time. PMID:11731165

  13. Recommendation for a Standardised Method of Broth Microdilution Susceptibility Testing for Porcine Bordetella bronchiseptica

    PubMed Central

    Prüller, Sandra; Frömke, Cornelia; Kaspar, Heike; Klein, Günter; Kreienbrock, Lothar; Kehrenberg, Corinna

    2015-01-01

    The objective was to establish and standardise a broth microdilution susceptibility testing method for porcine Bordetella (B.) bronchiseptica. B. bronchiseptica isolates from different geographical regions and farms were genotyped by macrorestriction analysis and subsequent pulsed-field gel electrophoresis. One reference and one type strain plus two field isolates of B. bronchiseptica were chosen to analyse growth curves in four different media: cation-adjusted Mueller-Hinton broth (CAMHB) with and without 2% lysed horse blood, Brain-Heart-Infusion (BHI), and Caso broth. The growth rate of each test strain in each medium was determined by culture enumeration and the suitability of CAMHB was confirmed by comparative statistical analysis. Thereafter, reference and type strain and eight epidemiologically unrelated field isolates of B. bronchiseptica were used to test the suitability of a broth microdilution susceptibility testing method following CLSI-approved performance standards given in document VET01-A4. Susceptibility tests, using 20 antimicrobial agents, were performed in five replicates, and data were collected after 20 and 24 hours incubation and statistically analysed. Due to the low growth rate of B. bronchiseptica, an incubation time of 24 hours resulted in significantly more homogeneous minimum inhibitory concentrations after five replications compared to a 20-hour incubation. An interlaboratory comparison trial including susceptibility testing of 24 antimicrobial agents revealed a high mean level of reproducibility (97.9%) of the modified method. Hence, in a harmonization for broth microdilution susceptibility testing of B. bronchiseptica, an incubation time of 24 hours in CAMHB medium with an incubation temperature of 35°C and an inoculum concentration of approximately 5 x 105 cfu/ml was proposed. PMID:25910232

  14. A Novel Method to Capture the Onset of Dynamic Electrocardiographic Ischemic Changes and its Implications to Arrhythmia Susceptibility

    PubMed Central

    Sayadi, Omid; Puppala, Dheeraj; Ishaque, Nosheen; Doddamani, Rajiv; Merchant, Faisal M.; Barrett, Conor; Singh, Jagmeet P.; Heist, E. Kevin; Mela, Theofanie; Martínez, Juan Pablo; Laguna, Pablo; Armoundas, Antonis A.

    2014-01-01

    Background This study investigates the hypothesis that morphologic analysis of intracardiac electrograms provides a sensitive approach to detect acute myocardial infarction or myocardial infarction‐induced arrhythmia susceptibility. Large proportions of irreversible myocardial injury and fatal ventricular tachyarrhythmias occur in the first hour after coronary occlusion; therefore, early detection of acute myocardial infarction may improve clinical outcomes. Methods and Results We developed a method that uses the wavelet transform to delineate electrocardiographic signals, and we have devised an index to quantify the ischemia‐induced changes in these signals. We recorded body‐surface and intracardiac electrograms at baseline and following myocardial infarction in 24 swine. Statistically significant ischemia‐induced changes after the initiation of occlusion compared with baseline were detectable within 30 seconds in intracardiac left ventricle (P<0.0016) and right ventricle–coronary sinus (P<0.0011) leads, 60 seconds in coronary sinus leads (P<0.0002), 90 seconds in right ventricle leads (P<0.0020), and 360 seconds in body‐surface electrocardiographic signals (P<0.0022). Intracardiac leads exhibited a higher probability of detecting ischemia‐induced changes than body‐surface leads (P<0.0381), and the right ventricle–coronary sinus configuration provided the highest sensitivity (96%). The 24‐hour ECG recordings showed that the ischemic index is statistically significantly increased compared with baseline in lead I, aVR, and all precordial leads (P<0.0388). Finally, we showed that the ischemic index in intracardiac electrograms is significantly increased preceding ventricular tachyarrhythmic events (P<0.0360). Conclusions We present a novel method that is capable of detecting ischemia‐induced changes in intracardiac electrograms as early as 30 seconds following myocardial infarction or as early as 12 minutes preceding tachyarrhythmic events. PMID

  15. The Traffic Noise Index: A Method of Controlling Noise Nuisance.

    ERIC Educational Resources Information Center

    Langdon, F. J.; Scholes, W. E.

    This building research survey is an analysis of the social nuisance caused by urban motor ways and their noise. The Traffic Noise Index is used to indicate traffic noises and their effects on architectural designs and planning, while suggesting the need for more and better window insulation and acoustical barriers. Overall concern is for--(1)…

  16. Correlation of different phenotypic drug susceptibility testing methods for four fluoroquinolones in Mycobacterium tuberculosis

    PubMed Central

    Coeck, Nele; de Jong, Bouke C.; Diels, Maren; de Rijk, Pim; Ardizzoni, Elisa; Van Deun, Armand; Rigouts, Leen

    2016-01-01

    Background Molecular resistance testing fails to explain all fluoroquinolone resistance, with a continued need for a suitable rapid phenotypic drug susceptibility testing method. Objective To evaluate the optimal method for phenotypic fluoroquinolone susceptibility testing. Methods Using Löwenstein–Jensen medium, Middlebrook 7H11 agar, BACTEC-MGIT 960 and the resazurin microtitre plate assay, we determined susceptibility to fluoroquinolones in Mycobacterium tuberculosis and investigated cross-resistance between ofloxacin, levofloxacin, moxifloxacin and gatifloxacin. We compared MICs of all four fluoroquinolones for 91 strains on Löwenstein–Jensen (as the gold standard) with their MICs in resazurin plates, and with ofloxacin susceptibility at a single concentration in MGIT and on 7H11 agar, in addition to sequencing of the gyrAB genes. Results and conclusions Applying a cut-off of 2 mg/L ofloxacin, 1 mg/L levofloxacin and 0.5 mg/L moxifloxacin and gatifloxacin in all methods, some discordance between solid medium and MGIT methods was observed, yet this tended to be explained by MICs around the cut-off. The high discordance between Löwenstein–Jensen (LJ) and resazurin plates suggests that the currently applied cut-offs for all fluoroquinolones in the resazurin method should decrease and minor changes in colour (from blue to purple) be considered as meaningful. High-level resistance in all assays to all drugs correlated well with the presence of gyrA mutations, in support of recent findings that fluoroquinolone resistance should be tested at different concentrations, as patients with lower levels of resistance may continue to benefit from high-dose fluoroquinolone-based therapy. PMID:26851609

  17. A comparative study of frequency ratio, weights of evidence and logistic regression methods for landslide susceptibility mapping: Sultan Mountains, SW Turkey

    NASA Astrophysics Data System (ADS)

    Ozdemir, Adnan; Altural, Tolga

    2013-03-01

    This study evaluated and compared landslide susceptibility maps produced with three different methods, frequency ratio, weights of evidence, and logistic regression, by using validation datasets. The field surveys performed as part of this investigation mapped the locations of 90 landslides that had been identified in the Sultan Mountains of south-western Turkey. The landslide influence parameters used for this study are geology, relative permeability, land use/land cover, precipitation, elevation, slope, aspect, total curvature, plan curvature, profile curvature, wetness index, stream power index, sediment transportation capacity index, distance to drainage, distance to fault, drainage density, fault density, and spring density maps. The relationships between landslide distributions and these parameters were analysed using the three methods, and the results of these methods were then used to calculate the landslide susceptibility of the entire study area. The accuracy of the final landslide susceptibility maps was evaluated based on the landslides observed during the fieldwork, and the accuracy of the models was evaluated by calculating each model's relative operating characteristic curve. The predictive capability of each model was determined from the area under the relative operating characteristic curve and the areas under the curves obtained using the frequency ratio, logistic regression, and weights of evidence methods are 0.976, 0.952, and 0.937, respectively. These results indicate that the frequency ratio and weights of evidence models are relatively good estimators of landslide susceptibility in the study area. Specifically, the results of the correlation analysis show a high correlation between the frequency ratio and weights of evidence results, and the frequency ratio and logistic regression methods exhibit correlation coefficients of 0.771 and 0.727, respectively. The frequency ratio model is simple, and its input, calculation and output processes are

  18. Direct in vitro comparison of six 3D positive contrast methods for susceptibility marker imaging

    PubMed Central

    Vonken, Evert-jan P. A.; Schär, Michael; Yu, Jing; Bakker, Chris J. G.; Stuber, Matthias

    2012-01-01

    Purpose To compare different techniques for positive contrast imaging of susceptibility markers with MRI for 3D visualization. As several different techniques have been reported, the choice of the suitable method depends on its properties with regard to the amount of positive contrast and the desired background suppression, as well as other imaging constraints needed for a specific application. Materials and methods Six different positive contrast techniques are investigated for their ability to image at 3T a single susceptibility marker in vitro. The white marker method (WM), susceptibility gradient mapping (SGM), inversion recovery with on-resonant water suppression (IRON), frequency selective excitation (FSX), fast low flip-angle positive contrast SSFP (FLAPS), and iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL) were implemented and investigated. Results The different methods were compared with respect to the volume of positive contrast, the product of volume and signal intensity, imaging time, and the level of background suppression. Quantitative results are provided and strengths and weaknesses of the different approaches are discussed. Conclusion The appropriate choice of positive contrast imaging technique depends on the desired level of background suppression, acquisition speed, and robustness against artifacts, for which in vitro comparative data is now available. PMID:23281151

  19. A study of large scaled landslide susceptibility by using Weight-of-Evidence method: A case study from the Laonung River Watershed, Southern Taiwan

    NASA Astrophysics Data System (ADS)

    Chen, Chih-Hao; Lin, Ching-Weei; Tseng, Chih-Ming

    2013-04-01

    The Laonung River watershed which covered an area 1367 km2 is selected as the study area to construct large scaled landslides susceptibility model by using Weight-of-Evidence method. Within the study area, 950 landslides with an area more than 10 ha are identified from FORMOSAT 2 images, aerial photos, and LiDAR derived 1 m high resolution Digital-Elevation-Model (DEM) taken after typhoon Moratko in 2009. Among these, 271 landslides occurred recently and they show bare ground in aerial photos and satellite images. 318 landslides are vegetation recovery, and they are inferred from their topographic characteristics by using aerial photos with topographic map. Additionally, 361 landslides with topographic features of deep seated landslide such as crown main escarpment, down slop scarp, up slop scarp, and transverse cracks are identified from 1m resolution LiDAR derived DEM. Weight-of-Evidence method is a bivariate statistical approach which uses the concept of Bayes' theorem and odds ratio to calculate the weighting of each evaluation parameter. In this study, ten parameters including slope gradient, slope aspect, landform, elevation, lithology, dip-slope, undercut slope, normalized difference vegetation index (NDVI), the distance from geological structure and the distance from stream are selected as evaluation factors. For each parameter, the weighting for landslide susceptibility is calculated, and the weighting of all parameters are then summed to generate the landslide susceptibility map. The study results show the area under the success rate curves reaching 80%, and 70% of large scaled landslides falls within top 30% susceptibility index. It implies that the susceptibility model constructed by this study can effectively predict the location of large scaled landslides in the study area. The results can benefit to the management of mitigation plan of the large scaled landslides in southern Taiwan.

  20. Inaccuracy of the Disk Diffusion Method Compared with the Agar Dilution Method for Susceptibility Testing of Campylobacter spp.

    PubMed Central

    Kotilainen, Pirkko; Puukka, Pauli; Nakari, Ulla-Maija; Siitonen, Anja; Eerola, Erkki; Huovinen, Pentti; Hakanen, Antti J.

    2012-01-01

    The agar dilution method has been standardized by the CLSI for the susceptibility testing of Campylobacter species, and according to these standards, the disk diffusion method should be used only in screening for macrolide and ciprofloxacin resistance. Nevertheless, the disk diffusion test is currently widely used, since it is easy to perform in clinical microbiology laboratories. In this study, the disk diffusion method was compared to the agar dilution method by analyzing the in vitro activities of seven antimicrobial agents against 174 Campylobacter strains collected in Finland between 2003 and 2008. Recommendations of the CLSI were followed using Mueller-Hinton agar plates with 5% of sheep blood. For each strain, the disk diffusion tests were performed two to four times. Of the 33 erythromycin-resistant strains (MIC, ≥16 μg/ml), 24 (73%) constantly showed a 6-mm erythromycin inhibition zone (i.e., no inhibition), while for seven strains the inhibition zone varied from 6 to 44 mm in repeated measurements. Among the 141 erythromycin-susceptible strains (MIC, <16 μg/ml), erythromycin inhibition zones varied between 6 and 61 mm. Of the 87 ciprofloxacin-resistant strains, 47 (54%) showed 6-mm inhibition zones, while 40 strains showed inhibition zones between 6 and 60 mm. Significant differences between the repetitions were observed in the disk diffusion for all antimicrobial agents and all strains except for the macrolide-resistant strains regarding the macrolides. For 17 (10%) strains, the variation in repeated measurements was substantial. These results show that the disk diffusion method may not be a reliable tool for the susceptibility testing of Campylobacter spp. Further studies are needed to assess whether the disk diffusion test could be improved or whether all susceptibilities of campylobacters should be tested using an MIC-based method. PMID:22075583

  1. Gradient index liquid crystal devices and method of fabrication thereof

    DOEpatents

    Lee, Jae-Cheul; Jacobs, Stephen

    1991-01-01

    Laser beam apodizers using cholesteric liquid crystals provides soft edge profile by use of two separate cholesteric liquid crystal mixtures with different selective reflection bands which in an overlap region have a gradient index where reflectivity changes as a function of position. The apodizers can be configured as a one-dimensional beam apod INTRODUCTION The U.S. government has rights in the invention under Contract No. DE-FC03-85DP40200 between the University of Rochester and the Department of Energy.

  2. Gradient index liquid crystal devices and method of fabrication thereof

    DOEpatents

    Lee, J.C.; Jacobs, S.

    1991-10-29

    Laser beam apodizers using cholesteric liquid crystals provides soft edge profile by use of two separate cholesteric liquid crystal mixtures with different selective reflection bands which in an overlap region have a gradient index where reflectivity changes as a function of position. The apodizers can be configured as a one-dimensional beam apod INTRODUCTION The U.S. government has rights in the invention under Contract No. DE-FC03-85DP40200 between the University of Rochester and the Department of Energy.

  3. Activity of fosfomycin and comparison of several susceptibility testing methods against contemporary urine isolates.

    PubMed

    Hirsch, Elizabeth B; Raux, Brian R; Zucchi, Paola C; Kim, Yisu; McCoy, Christopher; Kirby, James E; Wright, Sharon B; Eliopoulos, George M

    2015-12-01

    Fosfomycin is recommended as first-line treatment for acute uncomplicated cystitis in women. It has demonstrated in vitro activity against a variety of pathogens; however, a paucity of data are available from the USA. We determined the susceptibility of a collection of urine isolates to fosfomycin and compared multiple methods of susceptibility testing. Consecutive non-duplicate Enterobacteriaceae, enterococci and Pseudomonas aeruginosa isolates were collected from the clinical microbiology laboratory between August 2013 and January 2014. Isolates represented hospitalised or emergency department patients with monomicrobial bacteriuria. Fosfomycin MICs were determined in duplicate, on separate days, by Etest and disk diffusion and results were compared with agar dilution. Nitrofurantoin and ciprofloxacin were used as comparators. MIC results were categorised using Clinical and Laboratory Standards Institute interpretive criteria for Escherichia coli and Enterococcus faecalis. Correlation between the three testing methods was evaluated. Overall susceptibility to fosfomycin was 94.4%, 93.5% and 87.9% by agar dilution, disk diffusion and Etest, respectively. Five fosfomycin-resistant isolates were identified, including two Morganella morganii, one P. aeruginosa, one Proteus mirabilis and one Enterobacter aerogenes. Across all organisms, rates of essential agreement, categorical agreement, minor errors, major errors and very major errors for Etest/disk diffusion compared with agar dilution were 77.3%/NA, 89.5/93.8%, 7.1/5.0%, 3.6/1.3% and 0/0%, respectively. Fosfomycin displayed fairly consistent activity against a majority of isolates collected when using the susceptibility breakpoint of 64 μg/mL. MICs for E. coli were particularly low (≤2 μg/mL). These data lend support to current guidelines that recommend fosfomycin as empirical first-line therapy for uncomplicated UTI. PMID:26498988

  4. Modelling shallow landslide susceptibility by means of a subsurface flow path connectivity index and estimates of soil depth spatial distribution

    NASA Astrophysics Data System (ADS)

    Lanni, C.; Borga, M.; Rigon, R.; Tarolli, P.

    2012-11-01

    Topographic index-based hydrological models have gained wide use to describe the hydrological control on the triggering of rainfall-induced shallow landslides at the catchment scale. A common assumption in these models is that a spatially continuous water table occurs simultaneously across the catchment. However, during a rainfall event isolated patches of subsurface saturation form above an impeding layer and their hydrological connectivity is a necessary condition for lateral flow initiation at a point on the hillslope. Here, a new hydrological model is presented, which allows us to account for the concept of hydrological connectivity while keeping the simplicity of the topographic index approach. A dynamic topographic index is used to describe the transient lateral flow that is established at a hillslope element when the rainfall amount exceeds a threshold value allowing for (a) development of a perched water table above an impeding layer, and (b) hydrological connectivity between the hillslope element and its own upslope contributing area. A spatially variable soil depth is the main control of hydrological connectivity in the model. The hydrological model is coupled with the infinite slope stability model and with a scaling model for the rainfall frequency-duration relationship to determine the return period of the critical rainfall needed to cause instability on three catchments located in the Italian Alps, where a survey of soil depth spatial distribution is available. The model is compared with a quasi-dynamic model in which the dynamic nature of the hydrological connectivity is neglected. The results show a better performance of the new model in predicting observed shallow landslides, implying that soil depth spatial variability and connectivity bear a significant control on shallow landsliding.

  5. An improved method for susceptibility and radius quantification of cylindrical objects from MRI.

    PubMed

    Hsieh, Ching-Yi; Cheng, Yu-Chung N; Neelavalli, Jaladhar; Haacke, E Mark; Stafford, R Jason

    2015-05-01

    A new method is developed to measure the magnetic susceptibilities and radii of small cylinder-like objects at arbitrary orientations accurately. This method for most biological substances only requires a standard gradient echo sequence with one or two echo times, depending on the orientation of an object relative to the main magnetic field. For objects oriented at the magic angle, however, this method is not applicable. As a byproduct of this method, the cross-sectional area as well as signals inside and outside the object can be determined. The uncertainty of each measurement is estimated from the error propagation method. Partial volume, dephasing, and phase aliasing effects are naturally included in the equations of this method. A number of simulations, phantom, and pilot in-vivo human studies are carried out to validate the theory. When the maximal phase value at the boundary of a given cylindrical object is larger than 3 radians, and the phase inside the object is more than 1 radian, the susceptibility can be accurately quantified within 15%. The radius of the object can be determined to subpixel accuracy. This is the case when the signal-to-noise ratio inside the object is about 6:1 or higher and the radius of the object is about one pixel or larger. These conditions are realistic when considering medullary and pial veins for example. PMID:25633922

  6. An improved method for susceptibility and radius quantification of cylindrical objects from MRI

    PubMed Central

    Hsieh, Ching-Yi; Cheng, Yu-Chung N.; Neelavalli, Jaladhar; Haacke, E. Mark; Stafford, R. Jason

    2015-01-01

    A new method is developed to measure the magnetic susceptibilities and radii of small cylinder-like objects at arbitrary orientations accurately. This method for most biological substances only requires a standard gradient echo sequence with one or two echo times, depending on the orientation of an object relative to the main magnetic field. For objects oriented at the magic angle, however, this method is not applicable. As a byproduct of this method, the cross-sectional area as well as signals inside and outside the object can be determined. The uncertainty of each measurement is estimated from the error propagation method. Partial volume, dephasing, and phase aliasing effects are naturally included in the equations of this method. A number of simulations, phantom, and pilot in-vivo human studies are carried out to validate the theory. When the maximal phase value at the boundary of a given cylindrical object is larger than 3 radians, and the phase inside the object is more than 1 radian, the susceptibility can be accurately quantified within 15%. The radius of the object can be determined to subpixel accuracy. This is the case when the signal-to-noise ratio inside the object is about 6:1 or higher and the radius of the object is about one pixel or larger. These conditions are realistic when considering medullary and pial veins for example. PMID:25633922

  7. Susceptibility testing of filamentous fungi to amphotericin B by a rapid radiometric method

    SciTech Connect

    Merz, W.G.; Fay, D.; Thumar, B.; Dixon, D.

    1984-01-01

    A rapid, radiometric method was developed to determine the susceptibility of filamentous fungi to amphotericin B. The rapid, radiometric method depended on measurement of the inhibition of /sup 24/CO/sub 2/ production in the presence of amphotericin B. Thirty isolates of filamentous fungi were tested by the rapid, radiometric method and a reference agar dilution method. There was 93% agreement between the two methods when an 80% or greater decrease in CO/sub 2/ production was used to calculate the minimal inhibitory concentration with the rapid, radiometric method. Minimal inhibitory concentrations, based on 80% decrease of CO/sub 2/ production, were achieved within 24 h of incubation with all of the fungi tested.

  8. In vitro susceptibility of dermatomycoses agents to six antifungal drugs and evaluation by fractional inhibitory concentration index of combined effects of amorolfine and itraconazole in dermatophytes.

    PubMed

    Tamura, Takashi; Asahara, Miwa; Yamamoto, Mikachi; Yamaura, Mariko; Matsumura, Mitsuru; Goto, Kazuo; Rezaei-Matehkolaei, Ali; Mirhendi, Hossein; Makimura, Miho; Makimura, Koichi

    2014-01-01

    To investigate the antifungal drug susceptibility of fungi responsible for dermatomycoses, minimum inhibition concentration (MIC) tests were performed in 44 strains of dermatophytes, including Trichophyton rubrum, Trichophyton mentagrophytes, Trichophyton verrucosum, Trichophyton tonsurans, Microsporum canis, Microsporum gypseum and Epidermophyton floccosum, with six antifungal drugs (amorolfine, terbinafine, butenafine, ketoconazole, itraconazole and bifonazole) by broth microdilution assay according to Clinical Laboratory Standard Institute protocols. Six possible dermatomycosis-causing non-dermatophytic fungi were also tested. The two major causes of tinea, T. rubrum and T. mentagrophytes, showed significantly different sensitivities to ketoconazole and bifonazole. Clinically derived dermatophytes were sensitive to the six antifungal drugs tested. However, non-dermatophytes, especially Fusarium spp., tended to be resistant to these antifungal drugs. In Trichophyton spp., the MICs of non-azole drugs had narrower distributions than those of azoles. To evaluate the effects of antifungal drug combinations, the fractional inhibitory concentration index was calculated for the combination of amorolfine and itraconazole as representative external and internal drugs for dermatophytes. It was found that this combination had synergistic or additive effects on most dermatophytes, and had no antagonistic effects. The variation in susceptibility of clinically derived fungal isolates indicates that identification of causative fungi is indispensable for appropriately choosing effective antifungal drugs in the early stages of infection. The results of combination assay suggest that multiple drugs with different antifungal mechanisms against growth of dermatophytes should be used to treat refractory dermatomycoses, especially onychomycosis. PMID:24215461

  9. An analysis method for evaluating gradient-index fibers based on Monte Carlo method

    NASA Astrophysics Data System (ADS)

    Yoshida, S.; Horiuchi, S.; Ushiyama, Z.; Yamamoto, M.

    2011-05-01

    We propose a numerical analysis method for evaluating gradient-index (GRIN) optical fiber using the Monte Carlo method. GRIN optical fibers are widely used in optical information processing and communication applications, such as an image scanner, fax machine, optical sensor, and so on. An important factor which decides the performance of GRIN optical fiber is modulation transfer function (MTF). The MTF of a fiber is swayed by condition of manufacturing process such as temperature. Actual measurements of the MTF of a GRIN optical fiber using this method closely match those made by conventional methods. Experimentally, the MTF is measured using a square wave chart, and is then calculated based on the distribution of output strength on the chart. In contrast, the general method using computers evaluates the MTF based on a spot diagram made by an incident point light source. But the results differ greatly from those by experiment. In this paper, we explain the manufacturing process which affects the performance of GRIN optical fibers and a new evaluation method similar to the experimental system based on the Monte Carlo method. We verified that it more closely matches the experimental results than the conventional method.

  10. Antireflective graded index silica coating, method for making

    DOEpatents

    Yoldas, Bulent E.; Partlow, Deborah P.

    1985-01-01

    Antireflective silica coating for vitreous material is substantially non-reflecting over a wide band of radiations. This is achieved by providing the coating with a graded degree of porosity which grades the index of refraction between that of air and the vitreous material of the substrate. To prepare the coating, there is first prepared a silicon-alkoxide-based coating solution of particular polymer structure produced by a controlled proportion of water to alkoxide and a controlled concentration of alkoxide to solution, along with a small amount of catalyst. The primary solvent is alcohol and the solution is polymerized and hydrolized under controlled conditions prior to use. The prepared solution is applied as a film to the vitreous substrate and rapidly dried. It is thereafter heated under controlled conditions to volatilize the hydroxyl radicals and organics therefrom and then to produce a suitable pore morphology in the residual porous silica layer. The silica layer is then etched in order to enlarge the pores in a graded fashion, with the largest of the pores remaining being sufficiently small that radiations to be passed through the substrate are not significantly scattered. For use with quartz substrates, extremely durable coatings which display only 0.1% reflectivity have been prepared.

  11. Comparison of Etest with Modified Broth Microdilution Method for Testing Susceptibility of Aspergillus spp. to Voriconazole

    PubMed Central

    Serrano, M. C.; Morilla, D.; Valverde, A.; Chávez, M.; Espinel-Ingroff, A.; Claro, R.; Ramírez, M.; Mazuelos, E. Martín

    2003-01-01

    We compared the Etest with a broth microdilution method, performed according to a modified National Committee for Clinical Laboratory Standards guideline (M38-A), for determining the in vitro susceptibility of 77 isolates of Aspergillus spp. (26 A. fumigatus, 21 A. flavus, 10 A. terreus, 9 A. niger, 5 A. nidulellus, 4 A. glaucus, and 2 A. flavipes isolates). Overall, there was 92.2% agreement between both methods when Etest MICs were read at 24 h and 83.1% agreement when both methods were read at 48 h. When Etest MICs were read at 24 h, the agreement was >90% for all species tested except for A. fumigatus (84.6%). When Etest MICs were read at 48 h, the agreement ranged from 50 to 100%. The poorest agreement was seen with A. glaucus (50%) and A. fumigatus (65%). Where a discrepancy was observed between Etest and the reference method, the Etest MIC was generally higher. The Etest appears to be a suitable alternative procedure for testing the susceptibility of Aspergillus spp. to voriconazole. PMID:14605181

  12. On the susceptibility of numerical methods to computational chaos and superstability

    NASA Astrophysics Data System (ADS)

    Varsakelis, C.; Anagnostidis, P.

    2016-04-01

    In the present study, the susceptibility of the forward and the backward Euler methods to computational chaos and superstability is investigated via the means of both a theoretical analysis and numerical experiments. A linear stability analysis of the fixed points and the periodic orbits of the maps induced by these methods asserts that, for large enough time-steps Δt, these maps undergo bifurcations and as result the acquired solutions are spurious. More specifically, it is shown that the backward Euler method suppresses chaotic behavior, whereas the forward Euler renders all linearly stable fixed points and periodic orbits of its induced map linearly unstable. Numerical experiments that illustrate the validity of the theoretical analysis are also presented and discussed. For the forward Euler method, in particular, the computation of bifurcation diagrams, the Maximum Lyapunov exponent and the Kolmogorov-Sinai entropy suggest that it can engender computational chaos.

  13. A method for estimating the susceptibility of electronic systems to HPM

    SciTech Connect

    Mensing, R.W.; King, R.J.; Cabayan, H.S.

    1988-05-01

    In this report, a method for estimating the susceptibility of electronic systems to High Power Microwave (HPM) is advanced. This method is being incorporated into an overall DOD assessment methodology that is being prepared by a tri-service working group headed by the Air Force. In the next two years, the methodology will be applied to assess several military systems and modified as necessary to establish a nationally-approved standard methodology. The objective of the effort is to establish a standardized assessment methodology to guide all ongoing US HPM system effects assessment activities. The work will involve development of a detailed, integrated assessment plan that includes system functional analyses (i.e., system analyses and including all analytical modeling of HPM coupling and subsystem/component susceptibility), low power characterization test, (i.e., coupling/subsystem component tests and system functional response tests), HPM effects tests, and post-test analyses combining system functional analyses, low power characterization test, and methods for extrapolating test results to possible threat parameter regimes not readily simulated. 25 refs., 10 figs., 2 tabs.

  14. A new method for joint susceptibility artefact correction and super-resolution for dMRI

    NASA Astrophysics Data System (ADS)

    Ruthotto, Lars; Mohammadi, Siawoosh; Weiskopf, Nikolaus

    2014-03-01

    Diffusion magnetic resonance imaging (dMRI) has become increasingly relevant in clinical research and neuroscience. It is commonly carried out using the ultra-fast MRI acquisition technique Echo-Planar Imaging (EPI). While offering crucial reduction of acquisition times, two limitations of EPI are distortions due to varying magnetic susceptibilities of the object being imaged and its limited spatial resolution. In the recent years progress has been made both for susceptibility artefact correction and increasing of spatial resolution using image processing and reconstruction methods. However, so far, the interplay between both problems has not been studied and super-resolution techniques could only be applied along one axis, the slice-select direction, limiting the potential gain in spatial resolution. In this work we describe a new method for joint susceptibility artefact correction and super-resolution in EPI-MRI that can be used to increase resolution in all three spatial dimensions and in particular increase in-plane resolutions. The key idea is to reconstruct a distortion-free, high-resolution image from a number of low-resolution EPI data that are deformed in different directions. Numerical results on dMRI data of a human brain indicate that this technique has the potential to provide for the first time in-vivo dMRI at mesoscopic spatial resolution (i.e. 500μm) a spatial resolution that could bridge the gap between white-matter information from ex-vivo histology (≍1μm) and in-vivo dMRI (≍2000μm).

  15. A FORTRAN Program for Computing Refractive Index Using the Double Variation Method.

    ERIC Educational Resources Information Center

    Blanchard, Frank N.

    1984-01-01

    Describes a computer program which calculates a best estimate of refractive index and dispersion from a large number of observations using the double variation method of measuring refractive index along with Sellmeier constants of the immersion oils. Program listing with examples will be provided on written request to the author. (Author/JM)

  16. The lattice Boltzmann method for one-dimensional transient radiative transfer in graded index gray medium

    NASA Astrophysics Data System (ADS)

    Zhang, Yong; Yi, Hong-Liang; Tan, He-Ping

    2014-04-01

    The lattice Boltzmann method (LBM) is extended to solve transient radiative transfer in one-dimensional slab containing absorbing and scattering media with graded index subjected to a short square laser irradiation. By using a fully implicit backward differencing scheme to discretize the transient term in the radiative transfer equation, a new type of lattice structure is devised. Firstly, for the case of the refractive index matched boundary, LBM solutions to transient radiative transfer in graded index medium are validated by comparison with results reported in the literature. Afterward, LBM is employed to investigate transient radiative transfer in graded index medium with a refractive index discontinuity at the boundaries. Effects of the graded index distributions, the optical thickness, and scattering phase function on transmittance and reflectance signals are investigated, and several interesting trends on the time-resolved signals are observed and analyzed.

  17. Landslide susceptibility-certainty mapping by a multi-method approach: A case study in the Tertiary basin of Puy-en-Velay (Massif central, France)

    NASA Astrophysics Data System (ADS)

    Poiraud, Alexandre

    2014-07-01

    The present study discusses the use of integrated variables along with a combination of multi-method forecasts for landslide susceptibility mapping. The study area is located in the south-eastern French Massif central, a volcanic region containing Tertiary sedimentary materials that are prone to landslides. The flowage-type landslides within the study area are very slow-moving phenomena which affect the infrastructures and human settlements. The modelling process is based on a training set of landslides (70% of total landslides) and a set of controlling factor (slope, lithology, surficial formation, the topographic wetness index, the topographic position index, distance to thalweg, and aspect). We create a composite variable (or integrated variable), corresponding to the union of geology and surficial formation, in order to avoid the conditional dependence between these two variables and to build a geotechnical variable. We use five classical modelling methods (index, weight-of-evidence, logistic regression, decision tree, and unique condition unit) with the same training set but with different architectures of input data made up of controlling factors. All the models are tested with a validation group (30% of total landslides), using the Area Under the Receiver Operating Characteristic curve (AUC) to quantify their predictive performance. We finally select a single “best” model for each method. However, these five models are all equivalent in quality, despite their differences in detail, so no single model stands out against another. Finally, we combine the five models into a unique susceptibility map with a calculation of median susceptibility class. The final AUC value of this combined map is better than that for a single model (except for Unique Condition Unit), and we can evaluate the certainty of the susceptibility class pixel by pixel. In agreement with the sparse literature on this topic, we conclude that i) integrated variables increase the performance

  18. Rapid purity check method for susceptibility testing of M. tuberculosis complex with the MGIT 960 system.

    PubMed

    Huang, Tsi-Shu; Liu, Yung-Ching; Tu, Hui-Zin; Sy, Cheng-Len; Chen, Yao-Shen; Chen, Bao-Chen

    2007-01-01

    The Bactec MGIT 960 system is a rapid and reliable automated method for drug susceptibility testing of Mycobacterium tuberculosis complex (MTBC) that yields a high percentage of agreement with the standard method. The microscopic cord morphology of M. tuberculosis in liquid medium is characteristic, and readily differentiates MTBC from nontuberculous mycobacteria (NTM). The goals of this study were to describe the microscopic and macroscopic growth morphology of MTBC in antimicrobial-containing MGIT tubes and to evaluate the usefulness of the growth appearance during purity checking. The macroscopic cotton wool-like appearance of MTBC isolates in isoniazid (INH), streptomycin (SM), rifampin (RMP), and ethambutol (EMB)-containing tubes was observed in 97, 90, 93, and 71% of the isolates, respectively. The percentage of typical cord, loose, or frayed rope microscopic features in smears prepared from MTBC-positive cultures of INH, SM, RMP, and EMB-containing tubes was 96, 86, 97, and 71%, respectively. The sensitivity of the macroscopic morphology for predicting the purity of drug-containing MGIT tubes was 93%, while the microscopic morphology predicted the purity with a sensitivity rate of 92%. We found that simply examining the macroscopic morphology of the antimicrobial-containing MGIT tubes of drug-resistant MTBC isolates is useful in preventing false resistant results of susceptibility testing by the MGIT 960 system. PMID:18000288

  19. Susceptibility screening of hyphae-forming fungi with a new, easy, and fast inoculum preparation method.

    PubMed

    Schmalreck, Arno; Willinger, Birgit; Czaika, Viktor; Fegeler, Wolfgang; Becker, Karsten; Blum, Gerhard; Lass-Flörl, Cornelia

    2012-12-01

    In vitro susceptibility testing of clinically important fungi becomes more and more essential due to the rising number of fungal infections in patients with impaired immune system. Existing standardized microbroth dilution methods for in vitro testing of molds (CLSI, EUCAST) are not intended for routine testing. These methods are very time-consuming and dependent on sporulating of hyphomycetes. In this multicentre study, a new (independent of sporulation) inoculum preparation method (containing a mixture of vegetative cells, hyphae, and conidia) was evaluated. Minimal inhibitory concentrations (MIC) of amphotericin B, posaconazole, and voriconazole of 180 molds were determined with two different culture media (YST and RPMI 1640) according to the DIN (Deutsches Institut für Normung) microdilution assay. 24 and 48 h MIC of quality control strains, tested per each test run, prepared with the new inoculum method were in the range of DIN. YST and RPMI 1640 media showed similar MIC distributions for all molds tested. MIC readings at 48 versus 24 h yield 1 log(2) higher MIC values and more than 90 % of the MICs read at 24 and 48 h were within ± 2 log(2) dilution. MIC end point reading (log(2 MIC-RPMI 1640)-log(2 MIC-YST)) of both media demonstrated a tendency to slightly lower MICs with RPMI 1640 medium. This study reports the results of a new, time-saving, and easy-to-perform method for inoculum preparation for routine susceptibility testing that can be applied for all types of spore-/non-spore and hyphae-forming fungi. PMID:22864604

  20. Experimental method for the evaluation of the susceptibility of materials to shear band formation

    NASA Astrophysics Data System (ADS)

    Tham, R.

    2012-08-01

    In order to characterize materials with respect to their susceptibility to shear band formation at high strain rates, a modified Hopkinson pressure bar apparatus and hat-shaped steel specimens with a shear zone having a width significantly larger than the typical width of adiabatic bands are used. The sample is directly impacted by the striker. The force acting on the sample is measured with a PVDF-gauge between the sample and the output bar. The displacement is recorded with an electro-optical extensometer. The energy absorbed by the shearing process up to failure can be used as a reference for the susceptibility of materials to shear band formation. The method is demonstrated comparing the shear behavior of two high-strength steels with similar metallic structure and strength. Differences were found in the transition region between quasi-static and fully adiabatic shearing conditions where the energy up to rupture differs by 40 %. For fully adiabatic shear band formation, the deformation process of both materials equals. At extreme rates, shear processes are mainly governed by the thermodynamic properties of the materials. On the other hand, strength and structural properties play a role for low and intermediate rates where global and localized shear mechanisms occur in parallel.

  1. Case-parental control method in the search for disease-susceptibility genes

    SciTech Connect

    Khoury, M.J. )

    1994-08-01

    Historically, the search for disease-susceptibility genes has taken on two approaches, the linkage approach, traditionally the domain of the geneticist, and the association approach, traditionally the domain of the epidemiologist. The problem with association studies has been the choice of an appropriate control group with which cases can be compared with respect to the allelic distribution. The choice of appropriate controls has been extensively discussed in the epidemiology literature. To deal with confounding due to population stratification, sibling controls have been used as one group to adjust for genetic background. In the approach discussed by Knapp et al and Schaid and Sommer, the control group is a fictitious group formed by the parental alleles (at the locus of interest) that have not been transmitted to the proband. Cases and controls can then be compared with respect to the distribution of marker alleles at this locus, and measures of relative risk (haplotype or genotype relative risks) can be derived. The use of parental controls can provide a valuable method to search for disease-susceptibility genes for common diseases and to look for evidence of genotype-environment interaction. It is hoped that this methodology will be increasingly used in genetic-epidemiologic studies of disease.

  2. Determination of in vitro susceptibility of Mycobacterium tuberculosis to cephalosporins by radiometric and conventional methods

    SciTech Connect

    Heifets, L.B.; Iseman, M.D.; Cook, J.L.; Lindholm-Levy, P.J.; Drupa, I.

    1985-01-01

    Among eight cephalosporins and cephamycins tested in preliminary in vitro screening against Mycobacterium tuberculosis, the most promising for further study was found to be ceforanide, followed by ceftizoxime, cephapirin, and cefotaxime. Moxalactam, cefoxitin, cefamandole, and cephalothin were found to be not active enough against M. tuberculosis to be considered for further in vitro studies. The antibacterial activity of various ceforanide concentrations was investigated by three methods: (i) the dynamics of radiometric readings (growth index) in 7H12 broth; (ii) the number of CFU in the same medium; and (iii) the proportion method on 7H11 agar plates. There was a good correlation among the results obtained with these methods. The MIC for most strains ranged from 6.0 to 25.0 micrograms/ml. The BACTEC radiometric method is a reliable, rapid, and convenient method for preliminary screening and determination of the level of antibacterial activity of drugs not commonly used against M. tuberculosis.

  3. GIS based probabilistic analysis for shallow landslide susceptibility using Point Estimate Method

    NASA Astrophysics Data System (ADS)

    Park, Hyuck-Jin; Lee, Jung-Hyun

    2016-04-01

    The mechanical properties of soil materials (such as cohesion and friction angle) used in physically based model for landslide susceptibility analyses have been identified as the major source of uncertainty caused by complex geological conditions and spatial variability. In addition, limited sampling is another source of the uncertainty since the input parameters were obtained from broad areas. Therefore, in order to properly account for the uncertainty in mechanical parameters, the parameters were considered as random variables and the probabilistic analysis method has been used. In many previous researches, the Monte Carlo simulation has been widely used as the probabilistic analysis. However, since the Monte Carlo method requires a large number of repeated calculations and a great deal of calculation time to evaluate the probability of failure, it is not easy to adopt this approach to extensive study area due to a huge amount of computation time for regional study area. Therefore, this study proposes the alternative probabilistic analysis approach using the Point Estimate method (PEM), which has the advantage overcoming the shortcomings of the Monte Carlo simulation. This is because PEM requires only the mean and standard deviation of random variables and can obtain the probability of failure with a simple calculation. This proposed approach was performed in GIS based environments and applied to the study are which was experienced a large amount of landslides. The spatial database for input parameters and landslide inventory map were constructed in a grid-based GIS environment. To evaluate the performance of the model, the results of the landslide susceptibility assessment were compared with the landslide inventories using ROC graph.

  4. Automatic segmentation method of striatum regions in quantitative susceptibility mapping images

    NASA Astrophysics Data System (ADS)

    Murakawa, Saki; Uchiyama, Yoshikazu; Hirai, Toshinori

    2015-03-01

    Abnormal accumulation of brain iron has been detected in various neurodegenerative diseases. Quantitative susceptibility mapping (QSM) is a novel contrast mechanism in magnetic resonance (MR) imaging and enables the quantitative analysis of local tissue susceptibility property. Therefore, automatic segmentation tools of brain regions on QSM images would be helpful for radiologists' quantitative analysis in various neurodegenerative diseases. The purpose of this study was to develop an automatic segmentation and classification method of striatum regions on QSM images. Our image database consisted of 22 QSM images obtained from healthy volunteers. These images were acquired on a 3.0 T MR scanner. The voxel size was 0.9×0.9×2 mm. The matrix size of each slice image was 256×256 pixels. In our computerized method, a template mating technique was first used for the detection of a slice image containing striatum regions. An image registration technique was subsequently employed for the classification of striatum regions in consideration of the anatomical knowledge. After the image registration, the voxels in the target image which correspond with striatum regions in the reference image were classified into three striatum regions, i.e., head of the caudate nucleus, putamen, and globus pallidus. The experimental results indicated that 100% (21/21) of the slice images containing striatum regions were detected accurately. The subjective evaluation of the classification results indicated that 20 (95.2%) of 21 showed good or adequate quality. Our computerized method would be useful for the quantitative analysis of Parkinson diseases in QSM images.

  5. Development of an Antimicrobial Susceptibility Testing Method Suitable for Performing During Space Flight

    NASA Technical Reports Server (NTRS)

    Jorgensen, James H.; Skweres, Joyce A.; Mishra S. K.; McElmeel, M. Letticia; Maher, Louise A.; Mulder, Ross; Lancaster, Michael V.; Pierson, Duane L.

    1997-01-01

    Very little is known regarding the affects of the microgravity environment of space flight upon the action of antimicrobial agents on bacterial pathogens. This study was undertaken to develop a simple method for conducting antibacterial susceptibility tests during a Space Shuttle mission. Specially prepared susceptibility test research cards (bioMerieux Vitek, Hazelwood, MO) were designed to include 6-11 serial two-fold dilutions of 14 antimicrobial agents, including penicillins, cephalosporins, a Beta-lactamase inhibitor, vancomycin, erythromycin, tetracycline, gentamicin, ciprofloxacin, and trimethoprim/sulfamethoxazole. Minimal inhibitory concentrations (MICS) of the drugs were determined by visual reading of color endpoints in the Vitek research cards made possible by incorporation of a colorimetric growth indicator (alamarBlue(Trademark), Accumed International, Westlake, OH). This study has demonstrated reproducible susceptibility results when testing isolates of Staphylococcus aurezis, Group A Streptococcus, Enterococcusfaecalis, Escherichia coli (beta-lactamase positive and negative strains), Klebsiella pneumoniae, Enterobacter cloacae, and Pseudomoiias aeruginosa. In some instances, the MICs were comparable to those determined using a standard broth microdilution method, while in some cases the unique test media and format yielded slightly different values, that were themselves reproducible. The proposed in-flight experiment will include inoculation of the Vitek cards on the ground prior to launch of the Space Shuttle, storage of inoculated cards at refrigeration temperature aboard the Space Shuttle until experiment initiation, then incubation of the cards for 18-48 h prior to visual interpretation of MICs by the mission's astronauts. Ground-based studies have shown reproducible MICs following storage of inoculated cards for 7 days at 4-8 C to accommodate the mission's time schedule and the astronauts' activities. For comparison, ground-based control

  6. Research on the Construction Method of Comprehensive Evaluation Index of Geographic Conditions

    NASA Astrophysics Data System (ADS)

    Lv, S. H.; Zhang, J. X.; Zhang, Z. H.; Jiao, J. C.

    2016-06-01

    This article proposes a construction method for a comprehensive geographic conditions evaluation index based on geographic conditions survey data combined with thematic data on society, economy, ecology and population. This article constructs a three-level evaluation framework composed of index level, object level and factor level from the perspectives of ecological coordination, urban development, regional economic potential and basic public services, studies a method of acquiring all-level factor data on geographic conditions and discusses the comprehensive evaluation factor system of geographic conditions. The components of the all-level index are selected through principal component analysis, and iterative analysis is performed by innovatively setting conditions to ensure the independence of the factors and establish an evaluation factor set for geographic conditions. The weighting for the all-level index is obtained through the analytic hierarchy process resulting in the index of geographic conditions. From the perspective of geographic conditions, this article makes a dynamic and quantitative evaluation of national conditions and strengths to provide a reference basis for regional sustainable development and governmental management decisions. By using the method, this article first obtains the index of geographic conditions of Q city with comprehensive evaluation and analysis to verify the objectivity and scientific nature of the method and expand and deepen the application of survey data on geographic conditions.

  7. A Novel Pupillometric Method for Indexing Word Difficulty in Individuals With and Without Aphasia

    PubMed Central

    Hallowell, Brooke

    2015-01-01

    Purpose Cognitive effort is a clinically important facet of linguistic processing that is often overlooked in the assessment and treatment of people with aphasia (PWA). Furthermore, there is a paucity of valid ways to index cognitive effort in PWA. The construct of cognitive effort has been indexed for decades via pupillometry (measurement of pupil dilation and constriction during a cognitive task), yet pupillometry has not been implemented in studies including PWA. In the present study, we tested a novel method for indexing cognitive effort during linguistic processing in people with and without aphasia. Method Forty control participants and 39 PWA listened to semantically easy and difficult single nouns and looked at images while their pupillary responses were monitored. Mean pupil dilation in response to easy versus difficult nouns was calculated to index cognitive effort. Results Larger mean pupil dilation values were obtained for difficult compared with easy nouns for both groups. Conclusion Results provide preliminary evidence that pupillometry can be used to index cognitive effort during linguistic processing of single nouns in people with and without aphasia. Methods for indexing cognitive effort will be a valuable addition to existing assessment methods. Suggestions for further research are offered. PMID:26163655

  8. Methods and Applications of the Audibility Index in Hearing Aid Selection and Fitting

    PubMed Central

    Amlani, Amyn M.; Punch, Jerry L.; Ching, Teresa Y. C.

    2002-01-01

    During the first half of the 20th century, communications engineers at Bell Telephone Laboratories developed the articulation model for predicting speech intelligibility transmitted through different telecommunication devices under varying electroacoustic conditions. The profession of audiology adopted this model and its quantitative aspects, known as the Articulation Index and Speech Intelligibility Index, and applied these indices to the prediction of unaided and aided speech intelligibility in hearing-impaired listeners. Over time, the calculation methods of these indices—referred to collectively in this paper as the Audibility Index—have been continually refined and simplified for clinical use. This article provides (1) an overview of the basic principles and the calculation methods of the Audibility Index, the Speech Transmission Index and related indices, as well as the Speech Recognition Sensitivity Model, (2) a review of the literature on using the Audibility Index to predict speech intelligibility of hearing-impaired listeners, (3) a review of the literature on the applicability of the Audibility Index to the selection and fitting of hearing aids, and (4) a discussion of future scientific needs and clinical applications of the Audibility Index. PMID:25425917

  9. Susceptibility to Welding Cracking, Welding Sensitivity, Susceptibility to Welding Seam Cracking, and Test Methods for These Failures

    NASA Technical Reports Server (NTRS)

    Zeyen, K. L.

    1949-01-01

    In the years after the First World war a very rapid development, which even today has by no means come to an end, took place in the field of welding; here also, as in most technical innovations, failures made their appearance. Thereupon comprehensive Investigations were undertaken by steel manufacturers and consumers with cooperation of the authorities. b most cases the reasons for failure could be determined and eliminated and further occurrences avoided by the use of new test methods.

  10. Methods for Prediction of Refractive Index in Glasses for the Infrared

    SciTech Connect

    McCloy, John S.

    2011-06-14

    It is often useful to obtain custom glasses that meet particular requirements of refractive index and dispersion for high-end optical design and applications. In the case of infrared glasses, limited experimental data are available due to difficulties in processing of these glasses and also measuring refractive indices accurately. This paper proposes methods to estimate refractive index and dispersion as a function of composition for selected infrared-transmitting glasses. Methods for refractive index determination are reviewed and evaluated, including Gladstone-Dale, Wemple-DiDomenico single oscillator, Optical basicity, and Lorentz-Lorenz total polarizability. Various estimates for a set of PbO-Bi2O3-Ga2O3 (heavy metal oxide) and As-S (chalcogenide) glasses will be compared with measured values of index and dispersion.

  11. Rifampin Heteroresistance in Mycobacterium tuberculosis Cultures as Detected by Phenotypic and Genotypic Drug Susceptibility Test Methods

    PubMed Central

    Folkvardsen, Dorte Bek; Thomsen, Vibeke Ø.; Rigouts, Leen; Rasmussen, Erik Michael; Bang, Didi; Bernaerts, Gertjan; Werngren, Jim; Toro, Juan Carlos; Hoffner, Sven; Hillemann, Doris

    2013-01-01

    Tuberculosis patients may harbor both drug-susceptible and -resistant bacteria, i.e., heteroresistance. We used mixtures of rifampin-resistant and -susceptible Mycobacterium tuberculosis strains to simulate heteroresistance in patient samples. Molecular tests can be used for earlier discovery of multidrug resistance (MDR), but the sensitivity to detect heteroresistance is unknown. Conventional phenotypic drug susceptibility testing was the most sensitive, whereas two line probe assays and sequencing were unable to detect the clinically important 1% resistant bacteria. PMID:24068005

  12. In vitro antifungal susceptibility testing of Scopulariopsis brevicaulis strains using agar diffusion method.

    PubMed

    Skóra, Magdalena; Macura, Anna B

    2011-01-01

    The genus Scopulariopsis is a common soil saprotroph and has been isolated from air, organic waste and also from plant, animal and human tissues. Scopulariopsis has mainly been associated in humans with superficial mycoses, but it has also been described as the cause of subcutaneous and invasive infections. The most common aetiological agent of infections in humans is Scopulariopsis brevicaulis. This species has been reported to be resistant in vitro to broad-spectrum antifungal agents available today. The aim of the study was to establish in vitro antifungal susceptibility of 35 S. brevicaulis strains against amphotericin B (AMB), flucytosine (FC), caspofungin (CAS), terbinafine (TER), ciclopirox (CIC), voriconazole (VOR), clotrimazole (CTR), miconazole (MCZ), econazole (ECO), ketoconazole (KET), itraconazole (ITR), and fluconazole (FLU). Antifungal susceptibility tests were evaluated by an agar diffusion method (Neo-Sensitabs, Rosco, Denmark). AMB, FC, CAS, ITR and FLU showed no antifungal activity against S. brevicaulis. TER, CIC, CTR, KET, VOR, ECO, and MCZ revealed inhibitory activity for S. brevicaulis, but it varied for each of the drugs. The best antifungal effect was observed for TER and CIC. All isolates had large inhibition zones for TER and CIC. CTR was also inhibitory for all tested S. brevicaulis isolates, but the diameters of inhibition zones were smaller than for TER and CIC. Nearly 89% isolates showed inhibition zones for KET and the mean diameter of the inhibition zone was comparable to CTR. The least antifungal activity exhibited VQR, ECO and MCZ. Because of the multiresistance of S. brevicaulis, infections due to this species may not respond to particular antifungal treatment and other therapeutic approaches should be considered, e.g., combined therapy and/or surgery. PMID:21682097

  13. Refractive index gradient measurement across the thickness of a dielectric film by the prism coupling method

    SciTech Connect

    Sokolov, Viktor I; Panchenko, Vladislav Ya; Seminogov, V N

    2012-08-31

    A method is proposed for measuring the refractive index gradient n(z) in nonuniformly thick dielectric films. The method is based on the excitation of waveguide modes in a film using the prism coupling technique and on the calculation of n(z) and film thickness H{sub f} with the help of the angular positions of the TE or TM modes. The method can be used for an arbitrary shape of the index modulation over the film thickness in the limit of a small gradient [{Delta} n(z)/n(z) || 1]. (laser applications and other topics in quantum electronics)

  14. An in situ antimicrobial susceptibility testing method based on in vivo measurements of chlorophyll α fluorescence.

    PubMed

    Heliopoulos, Nikolaos S; Galeou, Angeliki; Papageorgiou, Sergios K; Favvas, Evangelos P; Katsaros, Fotios K; Stamatakis, Kostas

    2015-05-01

    Up to now antimicrobial susceptibility testing (AST) methods are indirect and generally involve the manual counting of bacterial colonies following the extraction of microorganisms from the surface under study and their inoculation in a separate procedure. In this work, an in situ, direct and instrumental method for the evaluation and assessment of antibacterial properties of materials and surfaces is proposed. Instead of indirectly determining antibacterial activity using the typical gram(-) test organisms with the subsequent manual colony count or inhibition zone measurement, the proposed procedure, employs photosynthetic gram(-) cyanobacteria deposited directly onto the surface under study and assesses cell proliferation and viability by a quick, accurate and reproducible instrumental chlorophyll fluorescence spectrophotometric technique. In contrast with existing methods of determination of antibacterial properties, it produces high resolution and quantitative results and is so versatile that it could be used to evaluate the antibacterial properties of any compound (organic, inorganic, natural or man-made) under any experimental conditions, depending on the targeted application. PMID:25771834

  15. Semi-vector iterative method for modes of high-index-contrast nanoscale waveguides.

    PubMed

    Gehlot, K; Sharma, A

    2013-04-22

    An approximate semi-analytical iterative method is presented to find vector modes of high-index contrast single mode waveguides. Present method is developed to provide improvement over scalar analysis of Vopt method. To illustrate the accuracy and efficiency of this method, modal properties of silicon strip nanoscale waveguide are studied in detail and compared with other approximate and rigorous numerical analysis. PMID:23609687

  16. Reliability of Hip Migration Index in Children with Cerebral Palsy: The Classic and Modified Methods

    PubMed Central

    Kim, Sun Mi; Sim, Eun Geol; Lim, Seong Gyu

    2012-01-01

    Objective To determine reliability and clinical use of two methods of migration index (MI) in CP patients with or without hip dysplasia. Method The materials included radiographs of 200 hips of children with cerebral palsy. Conventional anteroposterior radiographs of the pelvis were taken with the child in the supine position with standardized methods. Two rehabilitation doctors measured the migration index using two methods. In the classic method, the lateral margin of the acetabular roof was used as a landmark and in the modified method the lateral margin of the sourcil was used as a landmark. Each rater measured the migration index at three separate times with a time interval of at least one week. Intraclass correlation (ICC) was used to test the inter- and intra-rater reliability. Results MI shows excellent intra-rater reliability in both the classic and modified methods, but the inter-rater reliability was higher in the classic method than in the modified method. When categorized according to the sourcil classification, inter-rater reliability was higher in the normal sourcil type and lower in the dysplastic sourcil types. Conclusion Generally, the classic method showed higher reliability than the modified method, even though the reliability of the MI measurement was relatively high with both methods. PMID:22506233

  17. Landslide susceptibility mapping by combining the three methods Fuzzy Logic, Frequency Ratio and Analytical Hierarchy Process in Dozain basin

    NASA Astrophysics Data System (ADS)

    Tazik, E.; Jahantab, Z.; Bakhtiari, M.; Rezaei, A.; Kazem Alavipanah, S.

    2014-10-01

    Landslides are among the most important natural hazards that lead to modification of the environment. Therefore, studying of this phenomenon is so important in many areas. Because of the climate conditions, geologic, and geomorphologic characteristics of the region, the purpose of this study was landslide hazard assessment using Fuzzy Logic, frequency ratio and Analytical Hierarchy Process method in Dozein basin, Iran. At first, landslides occurred in Dozein basin were identified using aerial photos and field studies. The influenced landslide parameters that were used in this study including slope, aspect, elevation, lithology, precipitation, land cover, distance from fault, distance from road and distance from river were obtained from different sources and maps. Using these factors and the identified landslide, the fuzzy membership values were calculated by frequency ratio. Then to account for the importance of each of the factors in the landslide susceptibility, weights of each factor were determined based on questionnaire and AHP method. Finally, fuzzy map of each factor was multiplied to its weight that obtained using AHP method. At the end, for computing prediction accuracy, the produced map was verified by comparing to existing landslide locations. These results indicate that the combining the three methods Fuzzy Logic, Frequency Ratio and Analytical Hierarchy Process method are relatively good estimators of landslide susceptibility in the study area. According to landslide susceptibility map about 51% of the occurred landslide fall into the high and very high susceptibility zones of the landslide susceptibility map, but approximately 26 % of them indeed located in the low and very low susceptibility zones.

  18. Landslide susceptibility analysis in central Vietnam based on an incomplete landslide inventory: Comparison of a new method to calculate weighting factors by means of bivariate statistics

    NASA Astrophysics Data System (ADS)

    Meinhardt, Markus; Fink, Manfred; Tünschel, Hannes

    2015-04-01

    Vietnam is regarded as a country strongly impacted by climate change. Population and economic growth result in additional pressures on the ecosystems in the region. In particular, changes in landuse and precipitation extremes lead to a higher landslide susceptibility in the study area (approx. 12,400 km2), located in central Vietnam and impacted by a tropical monsoon climate. Hence, this natural hazard is a serious problem in the study area. A probability assessment of landslides is therefore undertaken through the use of bivariate statistics. However, the landslide inventory based only on field campaigns does not cover the whole area. To avoid a systematic bias due to the limited mapping area, the investigated regions are depicted as the viewshed in the calculations. On this basis, the distribution of the landslides is evaluated in relation to the maps of 13 parameters, showing the strongest correlation to distance to roads and precipitation increase. An additional weighting of the input parameters leads to better results, since some parameters contribute more to landslides than others. The method developed in this work is based on the validation of different parameter sets used within the statistical index method. It is called "omit error" because always omitting another parameter leads to the weightings, which describe how strong every single parameter improves or reduces the objective function. Furthermore, this approach is used to find a better input parameter set by excluding some parameters. After this optimization, nine input parameters are left, and they are weighted by the omit error method, providing the best susceptibility map with a success rate of 92.9% and a prediction rate of 92.3%. This is an improvement of 4.4% and 4.2%, respectively, compared to the basic statistical index method with the 13 input parameters.

  19. Agreement of Direct Antifungal Susceptibility Testing from Positive Blood Culture Bottles with the Conventional Method for Candida Species.

    PubMed

    Jabeen, Kauser; Kumar, Haresh; Farooqi, Joveria; Mehboob, Raunaq; Brandt, Mary E; Zafar, Afia

    2016-02-01

    Early availability of antifungal susceptibilities can ensure timely institution of targeted therapy in candidemia, which can improve patient outcomes. This study prospectively determines the agreement between the results of direct testing of antifungal susceptibilities from blood culture bottles by disk diffusion and Etest and the results of standardized susceptibility testing methods; direct testing would allow susceptibility results to be available 1 to 2 days earlier. A total of 104 blood cultures with different Candida species (28% C. albicans, 27% C. parapsilosis, 26% C. tropicalis, etc.) were evaluated between January 2012 and May 2013 for agreement of fluconazole, voriconazole, and amphotericin B susceptibility results by disk diffusion. Agreement in MICs obtained by Etest was determined for fluconazole (21 isolates), voriconazole (28 isolates), amphotericin (29 isolates), and caspofungin (29 isolates). The kappa scores for categorical agreement were highest for fluconazole by disk diffusion (0.902, standard error [SE] = 0.076) and Etest (1.00, SE = 0.218) and for amphotericin B by disk diffusion (1.00, SE = 0.098). The Pearson correlation (r) of zone diameters was strongest for fluconazole (0.69) and amphotericin (0.70) and moderate for voriconazole (0.60), and the Pearson correlation of MICs was strongest for fluconazole (0.94) and caspofungin (0.88). However, the moderate correlation of amphotericin MICs with zone diameters (-0.42) precludes the use of amphotericin B disk diffusion for susceptibility testing. There were no very major errors; however, there were 1 (1%) major and 5 (4.8%) minor errors with disk diffusion and 4 (13.3%) minor errors with Etest. Thus, antifungal disk diffusion directly from blood culture bottles is a rapid and easy method for fluconazole and voriconazole susceptibility testing for timely tailoring of candidemia therapy. PMID:26607985

  20. A modified method of vibration surveillance by using the optimal control at energy performance index

    NASA Astrophysics Data System (ADS)

    Kaliński, Krzysztof J.; Galewski, Marek A.

    2015-06-01

    A method of vibration surveillance by using the optimal control at energy performance index has been creatively modified. The suggested original modification depends on consideration of direct relationship between the measured acceleration signal and the optimal control command. The paper presents the results of experiments and Hardware-in-the-loop simulations of a new active vibration reduction algorithm based on the energy performance index idea modified in such a way, that it directly utilises the acceleration feedback signal. Promising prospects towards real application of the modified method in case of the high speed milling are predicted as well.

  1. [Identification of filamentous fungi isolated from clinical samples by two different methods and their susceptibility results].

    PubMed

    Direkel, Sahin; Otağ, Feza; Aslan, Gönül; Ulger, Mahmut; Emekdaş, Gürol

    2012-01-01

    Molds are widely distributed in nature. Aspergillus spp. represent the most frequently observed causative agents, however less frequent pathogens Fusarium, Scedosporium and Zygomycetes have also been considered the most important causes of morbidity and mortality in profoundly immunosuppressed hosts. The aims of this study were to identify filamentous fungi isolated from clinical specimens by conventional and molecular methods, and to detect their antifungal susceptibilities. A total of 6742 clinical specimens obtained from hospitalized patients at critical units of Mersin University Medical Faculty Hospital and sent to our laboratory between April 2008-January 2010 were included in the study. The isolates were identified by classical mycological methods and polymerase chain reaction-based DNA sequencing. Susceptibilities to fluconazole and voriconazole were tested by disk diffusion method and to fluconazole, voriconazole, amfoterisin B, caspofungin and posaconazole by E-test. Filamentous fungi were isolated from 71 (1.05%) samples (13 sputum, 4 wound, 4 peritoneal fluid, 3 extrenal ear discharge, 3 abscess and one of each cerebrospinal fluid, blood, tissue biopsy, nasal swab and conjunctival swab) which belonged to 32 patients (13 female, 19 male; age range 7 months-77 years, mean age: 46.6 years). Of the patients 62.3% presented one or more risk factors such as chronic renal failure (n= 8), chronic obstructive lung disease (n= 6), malignancy (n= 6), diabetes mellitus (n= 5) and peripheral vascular disease (n= 5). Of the isolates six were identified as Aspergillus niger, six as Aspergillus flavus, five as Aspergillus fumigatus, four as Aspergillus terreus, five as Fusarium spp., two as Bipolaris spp., and one of each as Acremonium spp., Aurebasidium spp., Mucor spp., and Scedosporium spp. By conventional methods. Three isolates exhibited different identities by DNA sequencing. All Aspergillus isolates were correctly identified at species level by both methods

  2. Polarimetry of moonlight: A new method for determining the refractive index of the lunar regolith

    NASA Astrophysics Data System (ADS)

    Fearnside, Andrew; Masding, Philip; Hooker, Chris

    2016-04-01

    We present a new method for remotely measuring the refractive index of the lunar regolith, using polarised moonlight. Umov's Law correlates the polarisation (Pmax) of scattered moonlight and the albedo (A) of the scattering lunar regolith. We discuss how deviations from this correlation have previously been linked to the so-called 'Polarimetric Anomaly Parameter', (Pmax)aA, which was proposed by Shkuratov and others as being related to variations in regolith grain size. We propose a reinterpretation of that parameter. We develop models of light scattering by regolith grains which predict that variation in the refractive index of regolith grains causes deviations from Umov's Law. Variations in other grain parameters such as grain size and degree of space weathering do not produce this deviation. The models are supported by polarimetric measurements on powdered terrestrial materials of differing refractive index. We derive a simple formula to express the relationship between refractive index and the deviation from Umov's Law and apply it to telescopic measurements of regions of the lunar surface. We show that the Aristarchus Plateau and the Marius Hills regions both comprise materials of unusually low refractive index. These results are consistent with recent estimates of the mineralogy of those areas. Picard and Peirce craters, in Mare Crisium, are shown to contain material of low refractive index similar to highland regions, as has been suggested by earlier studies of these craters.

  3. Method of determining effects of heat-induced irregular refractive index on an optical system.

    PubMed

    Song, Xifa; Li, Lin; Huang, Yifan

    2015-09-01

    The effects of an irregular refractive index on optical performance are examined. A method was developed to express a lens's irregular refractive index distribution. An optical system and its mountings were modeled by a thermomechanical finite element (FE) program in the predicted operating temperature range, -45°C-50°C. FE outputs were elaborated using a MATLAB optimization routine; a nonlinear least squares algorithm was adopted to determine which gradient equation best fit each lens's refractive index distribution. The obtained gradient data were imported into Zemax for sequential ray-tracing analysis. The root mean square spot diameter, modulation transfer function, and diffraction ensquared energy were computed for an optical system under an irregular refractive index and under thermoelastic deformation. These properties are greatly reduced by the irregular refractive index effect, which is one-third to five-sevenths the size of the thermoelastic deformation effect. Thus, thermal analyses of optical systems should consider not only thermoelastic deformation but also refractive index irregularities caused by inhomogeneous temperature. PMID:26368895

  4. Agar disk elution method for susceptibility testing of Mycobacterium marinum and Mycobacterium fortuitum complex to sulfonamides and antibiotics.

    PubMed Central

    Stone, M S; Wallace, R J; Swenson, J M; Thornsberry, C; Christensen, L A

    1983-01-01

    An agar disk elution method using round well plates, supplemented Mueller-Hinton agar, and commercial drug disks is described for susceptibility testing of Mycobacterium marinum and the rapidly growing mycobacteria to antibiotics and sulfonamides. By this method, 14 of 14 strains of M. marinum were susceptible to rifampin, doxycycline, minocycline, and trimethoprim-sulfamethoxazole. Identical results were obtained with Middlebrook 7H10 agar and drugs prepared from standard powders. With 58 isolates of Mycobacterium fortuitum and Mycobacterium chelonei, this method had a 92% correlation with broth minimal inhibitory concentration determinations for cefoxitin and greater than 98% for doxycycline, kanamycin, amikacin, and the sulfonamides. Sixty-nine percent of isolates of M. chelonei susceptible to amikacin on supplemented Mueller-Hinton agar were resistant on 7H10 agar, and 15 of 16 M. chelonei isolates susceptible to erythromycin in broth were resistant by disk elution when an endpoint of no growth was used with either agar. The agar disk elution method offers a practical method for testing of most antibacterial agents against these mycobacterial species. Images PMID:6651277

  5. A Simple Bayesian Climate Index Weighting Method for Seasonal Ensemble Forecasting

    NASA Astrophysics Data System (ADS)

    Bradley, A.; Habib, M. A.; Schwartz, S. S.

    2014-12-01

    Climate information — in the form of a measure of climate state or a climate forecast — can be an important predictor of future hydrologic conditions. For instance, streamflow variability for many locations around the globe is related to large-scale atmospheric oscillations, like the El Nino Southern Oscillation (ENSO) or the Pacific/Decadal Oscillation (PDO). Furthermore, climate forecast models are growing more skillful in their predictions of future climate variables on seasonal time scales. Finding effective ways to translate this climate information into improved hydrometeorological predictions is an area of ongoing research. In ensemble streamflow forecasting, where historical weather inputs or streamflow observations are used to generate the ensemble, climate index weighting is one way to represent the influence of current climate information. Using a climate index, each forecast variable member of the ensemble is selectively weighted to reflect climate conditions at the time of the forecast. A simple Bayesian climate index weighting of ensemble forecasts is presented. The original hydrologic ensemble members define a sample of the prior distribution; the relationship between the climate index and the ensemble member forecast variable is used to estimate a likelihood function. Given an observation of the climate index at the time of the forecast, the estimated likelihood function is then used to assign weights to each ensemble member. The weighted ensemble forecast is then used to estimate the posterior distribution of the forecast variable conditioned on the climate index. The proposed approach has several advantages over traditional climate index weighting methods. The weights assigned to the ensemble members accomplish the updating of the (prior) ensemble forecast distribution based on Bayes' Theorem, so the method is theoretically sound. The method also automatically adapts to the strength of the relationship between the climate index and the

  6. A Method to Measure Flame Index in Turbulent Partially-Premixed Flames

    NASA Astrophysics Data System (ADS)

    Rosenberg, David Ari

    This dissertation describes the development of a diagnostic technique and data processing routine to measure the flame index in partially-premixed flames, called the Flame Index Measurement Method. Many modern combustion applications involve conditions in which the fuel and oxidizer are only partially mixed prior to entering the flame. These partially-premixed flames contain some regions of premixed and some regions of non-premixed flamelets. New computational approaches use the flame index concept: premixed regions are identified and a premixed model is applied; non-premixed regions are also identified and a non-premixed model is applied. The flame index is defined as the normalized dot product of the gradients of the fuel and oxidizer mass fractions; it is +1 in premixed flamelets and is -1 in non-premixed flamelets. Previously there had been no experimentally measured values of flame index available to assess the modeling approaches. A new method has been developed to measure the flame index using planar laser-induced fluorescence tracers to indicate the sign and direction of the fuel and oxygen gradients. Through the modeling of premixed and non-premixed flamelets, acetone was selected as a fuel tracer and nitrogen dioxide was selected as an oxygen tracer. The fluorescence properties of both acetone and nitrogen dioxide were studied. With acetone seeded into the fuel, and nitrogen dioxide seeded into the air, the Flame Index Measurement Method was evaluated in laminar premixed and non-premixed methane/acetone/air flames, as well as in a well-defined turbulent partially-premixed burner, the Gas Turbine Model Combustor (GTMC). The flame index was measured in the GTMC with methane, propane, and syngas flames. Statistics (mean, variance, and probability mass functions) of the flame index are reported for the highly-turbulent partially-premixed GTMC flames. Two new statistical quantities were developed that describe the probability for the occurrence of premixed

  7. Susceptibilities of genital mycoplasmas to the newer quinolones as determined by the agar dilution method.

    PubMed Central

    Kenny, G E; Hooton, T M; Roberts, M C; Cartwright, F D; Hoyt, J

    1989-01-01

    The increasing resistance of genital mycoplasmas to tetracycline poses a problem because tetracycline is one of the few antimicrobial agents active against Mycoplasma hominis, Ureaplasma urealyticum, chlamydiae, gonococci, and other agents of genitourinary-tract disease. Since the quinolones are a promising group of antimicrobial agents, the susceptibilities of M. hominis and U. urealyticum to the newer 6-fluoroquinolones were determined by the agar dilution method. Ciprofloxacin, difloxacin, and ofloxacin had good activity against M. hominis, with the MIC for 50% of isolates tested (MIC50) being 1 microgram/ml. Fleroxacin, lomefloxacin, pefloxacin, and rosoxacin had MIC50s of 2 micrograms/ml. Enoxacin, norfloxacin, and amifloxacin had MIC50s of 8 to 16 micrograms/ml, and cinoxacin and nalidixic acid were inactive (MIC50, greater than or equal to 256 micrograms/ml). Overall, the activities of 6-fluoroquinolones for ureaplasmas were similar to those for M. hominis, with MICs being the same or twofold greater. The most active 6-fluoroquinolones against ureaplasmas were difloxacin, ofloxacin, and pefloxacin, with MIC50s of 1 to 2 micrograms/ml. Ciprofloxacin was unusual in that the MIC50 for M. hominis was 1 microgram/ml, whereas the MIC50 for ureaplasmas was 8 micrograms/ml. Since the MIC50s for the most active quinolones approximate achievable concentrations in blood and urine, quinolones have promise in treating mycoplasmal infections. PMID:2712541

  8. CLSI broth microdilution method for testing susceptibility of Malassezia pachydermatis to thiabendazole

    PubMed Central

    Nascente, Patrícia da Silva; Meinerz, Ana Raquel Mano; de Faria, Renata Osório; Schuch, Luiz Filipe Damé; Meireles, Mário Carlos Araújo; de Mello, João Roberto Braga

    2009-01-01

    Thiabendazole, classified as antiparasitic and also used as an antifungal drug, can be found as otological solution indicated for treatment of parasitic and fungal external otitis in small animals. Malassezia pachydermatis is a yeast recognized as a normal inhabitant on the skin and mucous membranes of dogs and cats. However, it is considered an opportunistic agent that causes external otitis and dermatitis in these animals. The aim of this study was to evaluate the in vitro effect of thiabendazole against 51 isolates of M. pachydermatis using the CLSI Broth Microdilution method that has been adapted for this yeast species (NCCLS, 2002). Based on this test, the Minimum Inhibitory Concentrations (MIC) of thiabendazol was calculated. Subsequently, the susceptibility of each isolate against this antifungal was determined. It was observed that the MIC of thiabendazole against M. pachydermatis ranged from 0.03 to > 4 µg/mL. A total of 13.7% of the isolates were found to be resistant, 47.1% were intermediate and 39.2% were sensitive to the drug. The rate of resistance of the yeasts against thiabendazole was similar to the results previously obtained with other antifungals, while the adapted broth microdilution technique used in this study proved to be efficient. PMID:24031347

  9. A simple statistical method for analyzing flood susceptibility with incorporating rainfall and impervious surface

    NASA Astrophysics Data System (ADS)

    Chiang, Shou-Hao; Chen, Chi-Farn

    2016-04-01

    Flood, as known as the most frequent natural hazard in Taiwan, has induced severe damages of residents and properties in urban areas. The flood risk is even more severe in Tainan since 1990s, with the significant urban development over recent decades. Previous studies have indicated that the characteristics and the vulnerability of flood are affected by the increase of impervious surface area (ISA) and the changing climate condition. Tainan City, in southern Taiwan is selected as the study area. This study uses logistic regression to functionalize the relationship between rainfall variables, ISA and historical flood events. Specifically, rainfall records from 2001 to 2014 were collected and mapped, and Landsat images of year 2001, 2004, 2007, 2010 and 2014 were used to generate the ISA with SVM (support vector machine) classifier. The result shows that rainfall variables and ISA are significantly correlated to the flood occurrence in Tainan City. With applying the logistic function, the likelihood of flood occurrence can be estimated and mapped over the study area. This study suggests the method is simple and feasible for rapid flood susceptibility mapping, when real-time rainfall observations can be available, and it has potential for future flood assessment, with incorporating climate change projections and urban growth prediction.

  10. Comparison of E-test with agar dilution methods in testing susceptibility of N. gonorrhoeae to azithromycin.

    PubMed

    Yasin, R M; Suan, K A; Meng, C Y

    1997-05-01

    A single dose of a new antibiotic, azithromycin, has been shown to be effective in the treatment of uncomplicated Neisseria gonorrhoeae. A clinical study was conducted to assess the in vitro susceptibility of N gonorrhoeae to azithromycin and compare the reliability of results obtained using the new E-test methodology for determination of the minimum inhibitory concentration (MIC) of antibiotic with those obtained through the standard agar dilution method. 135 clinical isolates of N gonorrhoeae were obtained from patients attending hospital-based sexually transmitted disease clinics in five geographic locations in Malaysia. 76 of the isolates were penicillinase-producing N gonorrhoeae and 69 were high-level tetracycline-resistant N gonorrhoeae. All isolates were susceptible to azithromycin based on the susceptible MIC breakpoint of 2.0 mcg/ml. The MICs ranged from 0.0078-0.25 mcg/ml by agar dilution method and from 0.016-0.50 mcg/ml by E-test. Agreement between these two methods was 97.8%. The single-dose regime and good antigonococcal and antichlamydial activity of azithromycin make this antibiotic a suitable treatment choice. Moreover, the findings of this study suggest that the simpler, faster E-test is as reliable as the agar dilution method. Given the tendency of the antimicrobial susceptibility pattern of N gonorrhoeae to change rapidly, it is important to monitor MICs to detect the emergence of resistance. PMID:9153733

  11. Fabrication of graded-index plastic optical fiber by the diffusion-assisted coextrusion method

    NASA Astrophysics Data System (ADS)

    Sohn, In-Sung

    Recently, plastic optical fibers (POFs) have drawn significant attention as high-speed transmission media due to their advantages over conventional glass optical fibers such as flexibility and durability. In addition, Grade-Index (GRIN) POFs with smoothly varying refractive indices provide increased data transmission speeds suitable for the short-distance communications such as local area networking or home networking. In this research, the diffusion-assisted coextrusion process is introduced as a method to fabricate GRIN POFs. In this process, two or more polymeric materials containing additives for refractive index modification are fed separately into a coextrusion die where a concentric multi-layer structure is formed. Subsequently, the diffusion of additives take places in a diffusion zone creating a non-equilibrium concentration profile, hence the refractive index profile. A theoretical analysis for the prediction of the refractive index profile obtainable by this process indicates that it is difficult to obtain a near-parabolic refractive index profile with the tubular flow design unless a very large residence time in the diffusion zone is provided. However, significant changes in the refractive index profile can be induced by adopting a multi-layer approach and an annulus flow design. Furthermore, the bandwidth estimated by the ray analysis indicates that even a small variation of the refractive index profile created by the additive diffusion can result in a significant increase in the bandwidth. To verify the findings from theoretical analysis, poly(methyl methacrylate)-base GRIN POFs with diphenyl sulfide and diphenyl sulfoxide as refractive index-modifying dopants were prepared and the effects of various operating conditions such as melt temperatures, flow rates and core-cladding interface positions were investigated. The dopant concentration profile, thus the refractive index profile, characterized by FT-IR spectroscopy, has been shown to be controllable

  12. A novel technique for modeling susceptibility-based contrast mechanisms for arbitrary microvascular geometries: the finite perturber method.

    PubMed

    Pathak, Arvind P; Ward, B Douglas; Schmainda, Kathleen M

    2008-04-15

    Recently, we demonstrated that vessel geometry is a significant determinant of susceptibility-induced contrast in MRI. This is especially relevant for susceptibility-contrast enhanced MRI of tumors with their characteristically abnormal vessel morphology. In order to better understand the biophysics of this contrast mechanism, it is of interest to model how various factors, including microvessel morphology contribute to the measured MR signal, and was the primary motivation for developing a novel computer modeling approach called the Finite Perturber Method (FPM). The FPM circumvents the limitations of traditional fixed-geometry approaches, and enables us to study susceptibility-induced contrast arising from arbitrary microvascular morphologies in 3D, such as those typically observed with brain tumor angiogenesis. Here we describe this new modeling methodology and some of its applications. The excellent agreement of the FPM with theory and the extant susceptibility modeling data, coupled with its computational efficiency demonstrates its potential to transform our understanding of the factors that engender susceptibility contrast in MRI. PMID:18308587

  13. In vitro resistance of clinical Fusarium species to amphotericin B and voriconazole using the EUCAST antifungal susceptibility method.

    PubMed

    Taj-Aldeen, Saad J; Salah, Husam; Al-Hatmi, Abdullah M S; Hamed, Manal; Theelen, Bart; van Diepeningen, Anne D; Boekhout, Teun; Lass-Flörl, Cornelia

    2016-08-01

    Susceptibility testing using the EUCAST-AFST method against 39 clinical Fusarium strains consecutively collected from local and invasive infections during the last 10years assessed the in vitro activities of amphotericin B (AmB) and triazole antifungal agents. In addition, the susceptibility pattern of 12 reference strains from the CBS-KNAW Fungal Biodiversity Centre (CBS) was evaluated. In particular Fusarium petroliphilum and F. solani sensu lato were involved in disseminated infections and known for treatment failure. AmB displayed the lowest MICs followed by voriconazole VRC, posaconazole (POC). Itraconazole (ITC) showed high MIC values, displaying in vitro resistance. Clinical isolates were significantly (P <0.05) more resistant to AmB, VRC, and POC, than the CBS reference isolates probably due to previous exposure to antifungal therapy. Resistant profiles to AmB and VRC, which are the currently recommended agents in the guidelines for treatments, and a late diagnosis may be associated with high mortality rate in immunocompromised patients. The present antifungal susceptibility profiles showed that species- and strain-specific differences in antifungal susceptibility exist within Fusarium and that susceptibility testing is important and may improve the prognosis of these infections. PMID:27312690

  14. Using the Method of Water Poverty Index (WPI) to Evaluate the Region Water Security

    NASA Astrophysics Data System (ADS)

    Fu, Q.; Kachanoski, G.

    2008-12-01

    Water security is a widely concerned issue in the world nowadays. A new method, water poverty index (WPI), has been used to evaluate the regional water security. Twelve state farms in Heilongjiang Province, Northeastern China were selected to evaluate water security status based on the data of 2006 by using WPI and mean deviation grading method. The method of WPI includes five key indexes, such as resources(R), access (A), capacity(C), utilization (U) and environment (E). Each key index includes several sub-indexes. According to the results of WPI, the grade of each farm has been calculated by using the method of mean deviation grading. Thus, the radar images can be protracted of each farm. From the radar images, the conclusions can be drawn that the WPI values of Farms 853 and Hongqiling were in very safe status, while that of Farm Raohe was in safe status, those of Farms Youyi, 597, 852, 291 and Jiangchuan were in moderate safe status, that of Farm Beixing was in low safe status and those of Farms Shuangyashan, Shuguang and Baoshan were in unsafe status. The results from this study can provide basic information for decision making on rational use of water resources and regulations for regional water safety guarantee system.

  15. Determination of the slow crack growth susceptibility coefficient of dental ceramics using different methods.

    PubMed

    Gonzaga, Carla Castiglia; Cesar, Paulo Francisco; Miranda, Walter Gomes; Yoshimura, Humberto Naoyuki

    2011-11-01

    This study compared three methods for the determination of the slow crack growth susceptibility coefficient (n) of two veneering ceramics (VM7 and d.Sign), two glass-ceramics (Empress and Empress 2) and a glass-infiltrated alumina composite (In-Ceram Alumina). Discs (n = 10) were prepared according to manufacturers' recommendations and polished. The constant stress-rate test was performed at five constant stress rates to calculate n(d) . For the indentation fracture test to determine n(IF) , Vickers indentations were performed and the crack lengths were measured under an optical microscope. For the constant stress test (performed only for d.Sign for the determination of n(s) ) four constant stresses were applied and held constant until the specimens' fracture and the time to failure was recorded. All tests were performed in artificial saliva at 37°C. The n(d) values were 17.2 for Empress 2, followed by d.Sign (20.5), VM7 (26.5), Empress (30.2), and In-Ceram Alumina (31.1). In-Ceram Alumina and Empress 2 showed the highest n(IF) values, 66.0 and 40.2, respectively. The n(IF) values determined for Empress (25.2), d.Sign (25.6), and VM7 (20.1) were similar. The n(s) value determined for d.Sign was 31.4. It can be concluded that the n values determined for the dental ceramics evaluated were significantly influenced by the test method used. PMID:21714087

  16. Evaluation of five susceptibility test methods for detection of tobramycin resistance in a cluster of epidemiologically related Acinetobacter baumannii isolates.

    PubMed

    Moodley, V Mischka; Oliver, Stephen P; Shankland, Iva; Elisha, B Gay

    2013-08-01

    Acinetobacter baumannii is a major nosocomial pathogen causing infections in critically ill patients. This organism has acquired the propensity to rapidly develop resistance to most antibiotics. At several hospitals within Cape Town, South Africa, tobramycin and colistin are frequently the only therapeutic options. Vitek2 automated susceptibility testing (AST) is used in the clinical laboratory to determine selected susceptibility profiles. The suspicion of a possible AST-related technical error when testing for susceptibility to tobramycin in A. baumannii precipitated this study. Thirty-nine A. baumannii strains isolated from clinical specimens (June to December 2006) were included in this prospective study. Tobramycin susceptibility testing results obtained by AST, disc diffusion, the epsilometer test (Etest), and agar dilution were compared to those for broth microdilution (BMD), the reference method. The tobramycin susceptibility results revealed errors in 25/39 (64%) isolates (10 very major and 15 minor errors) when AST was compared to BMD, 12/39 (31%) (2 very major and 10 minor errors) when Etest was compared to BMD, 16/39 (41%) (3 very major and 13 minor errors) when disc diffusion was compared to BMD, and 21/39 (54%) (10 very major and 11 minor errors) when agar dilution was compared to BMD. Using PCR, we detected aac(3)-IIa, which is associated with tobramycin resistance, in 21/25 of the discrepant isolates. Molecular typing (using pulsed-field gel electrophoresis and repetitive sequence-based PCR [rep-PCR]) showed that these isolates were genetically related. Clinical laboratories that routinely use the Vitek2 system should consider an alternative testing method for determining susceptibility to tobramycin. PMID:23698528

  17. Estimation of intrinsic aquifer vulnerability with index-overlay and statistical methods: the case of eastern Kopaida, central Greece

    NASA Astrophysics Data System (ADS)

    Tziritis, E.; Lombardo, L.

    2016-03-01

    The intrinsic vulnerability of a karstic aquifer system in central Greece was jointly assessed with the use of a statistical approach and PI method, as a function of topography, protective cover effectiveness and the degree to which this cover is bypassed due to flow conditions. The input data for the index-overlay PI method were derived from field works and 71 boreholes of the area; the information was obtained, subsequently its critical factors were compiled which included lithology, fissuring and karstification of bedrock, soil characteristics, hydrology, hydrogeology, topography and vegetation. The aforementioned parameters were processed jointly with the aid of a GIS and yielded the final estimation of intrinsic aquifer vulnerability to contamination. Results were compared with an equivalent spatially distributed probability map obtained through a stochastic approach. The calibration and test phase of the latter relied on morphometric conditions derived by terrain analyses of a digital elevation model as well as on geology and land use from thematic maps. This procedure allowed taking into account the topographic influences with respect to a deep system such as the local karstic aquifer of eastern Kopaida basin. Finally, results were validated with ground truth nitrate values obtained from 41 groundwater samples, highlighted the spatial delineation of susceptible areas to contamination in both cases and provided a robust tool for regional planning actions and water resources management schemes.

  18. Hybrid finite volume/ finite element method for radiative heat transfer in graded index media

    NASA Astrophysics Data System (ADS)

    Zhang, L.; Zhao, J. M.; Liu, L. H.; Wang, S. Y.

    2012-09-01

    The rays propagate along curved path determined by the Fermat principle in the graded index medium. The radiative transfer equation in graded index medium (GRTE) contains two specific redistribution terms (with partial derivatives to the angular coordinates) accounting for the effect of the curved ray path. In this paper, the hybrid finite volume with finite element method (hybrid FVM/FEM) (P.J. Coelho, J. Quant. Spectrosc. Radiat. Transf., vol. 93, pp. 89-101, 2005) is extended to solve the radiative heat transfer in two-dimensional absorbing-emitting-scattering graded index media, in which the spatial discretization is carried out using a FVM, while the angular discretization is by a FEM. The FEM angular discretization is demonstrated to be preferable in dealing with the redistribution terms in the GRTE. Two stiff matrix assembly schemes of the angular FEM discretization, namely, the traditional assembly approach and a new spherical assembly approach (assembly on the unit sphere of the solid angular space), are discussed. The spherical assembly scheme is demonstrated to give better results than the traditional assembly approach. The predicted heat flux distributions and temperature distributions in radiative equilibrium are determined by the proposed method and compared with the results available in other references. The proposed hybrid FVM/FEM method can predict the radiative heat transfer in absorbing-emitting-scattering graded index medium with good accuracy.

  19. A Hybrid Spatio-Temporal Data Indexing Method for Trajectory Databases

    PubMed Central

    Ke, Shengnan; Gong, Jun; Li, Songnian; Zhu, Qing; Liu, Xintao; Zhang, Yeting

    2014-01-01

    In recent years, there has been tremendous growth in the field of indoor and outdoor positioning sensors continuously producing huge volumes of trajectory data that has been used in many fields such as location-based services or location intelligence. Trajectory data is massively increased and semantically complicated, which poses a great challenge on spatio-temporal data indexing. This paper proposes a spatio-temporal data indexing method, named HBSTR-tree, which is a hybrid index structure comprising spatio-temporal R-tree, B*-tree and Hash table. To improve the index generation efficiency, rather than directly inserting trajectory points, we group consecutive trajectory points as nodes according to their spatio-temporal semantics and then insert them into spatio-temporal R-tree as leaf nodes. Hash table is used to manage the latest leaf nodes to reduce the frequency of insertion. A new spatio-temporal interval criterion and a new node-choosing sub-algorithm are also proposed to optimize spatio-temporal R-tree structures. In addition, a B*-tree sub-index of leaf nodes is built to query the trajectories of targeted objects efficiently. Furthermore, a database storage scheme based on a NoSQL-type DBMS is also proposed for the purpose of cloud storage. Experimental results prove that HBSTR-tree outperforms TB*-tree in some aspects such as generation efficiency, query performance and query type. PMID:25051028

  20. A hybrid spatio-temporal data indexing method for trajectory databases.

    PubMed

    Ke, Shengnan; Gong, Jun; Li, Songnian; Zhu, Qing; Liu, Xintao; Zhang, Yeting

    2014-01-01

    In recent years, there has been tremendous growth in the field of indoor and outdoor positioning sensors continuously producing huge volumes of trajectory data that has been used in many fields such as location-based services or location intelligence. Trajectory data is massively increased and semantically complicated, which poses a great challenge on spatio-temporal data indexing. This paper proposes a spatio-temporal data indexing method, named HBSTR-tree, which is a hybrid index structure comprising spatio-temporal R-tree, B*-tree and Hash table. To improve the index generation efficiency, rather than directly inserting trajectory points, we group consecutive trajectory points as nodes according to their spatio-temporal semantics and then insert them into spatio-temporal R-tree as leaf nodes. Hash table is used to manage the latest leaf nodes to reduce the frequency of insertion. A new spatio-temporal interval criterion and a new node-choosing sub-algorithm are also proposed to optimize spatio-temporal R-tree structures. In addition, a B*-tree sub-index of leaf nodes is built to query the trajectories of targeted objects efficiently. Furthermore, a database storage scheme based on a NoSQL-type DBMS is also proposed for the purpose of cloud storage. Experimental results prove that HBSTR-tree outperforms TB*-tree in some aspects such as generation efficiency, query performance and query type. PMID:25051028

  1. Bin-Hash Indexing: A Parallel Method for Fast Query Processing

    SciTech Connect

    Bethel, Edward W; Gosink, Luke J.; Wu, Kesheng; Bethel, Edward Wes; Owens, John D.; Joy, Kenneth I.

    2008-06-27

    This paper presents a new parallel indexing data structure for answering queries. The index, called Bin-Hash, offers extremely high levels of concurrency, and is therefore well-suited for the emerging commodity of parallel processors, such as multi-cores, cell processors, and general purpose graphics processing units (GPU). The Bin-Hash approach first bins the base data, and then partitions and separately stores the values in each bin as a perfect spatial hash table. To answer a query, we first determine whether or not a record satisfies the query conditions based on the bin boundaries. For the bins with records that can not be resolved, we examine the spatial hash tables. The procedures for examining the bin numbers and the spatial hash tables offer the maximum possible level of concurrency; all records are able to be evaluated by our procedure independently in parallel. Additionally, our Bin-Hash procedures access much smaller amounts of data than similar parallel methods, such as the projection index. This smaller data footprint is critical for certain parallel processors, like GPUs, where memory resources are limited. To demonstrate the effectiveness of Bin-Hash, we implement it on a GPU using the data-parallel programming language CUDA. The concurrency offered by the Bin-Hash index allows us to fully utilize the GPU's massive parallelism in our work; over 12,000 records can be simultaneously evaluated at any one time. We show that our new query processing method is an order of magnitude faster than current state-of-the-art CPU-based indexing technologies. Additionally, we compare our performance to existing GPU-based projection index strategies.

  2. The relationship of motion sickness susceptibility to learned autonomic control for symptom suppression

    NASA Technical Reports Server (NTRS)

    Cowings, P. S.; Toscano, W. B.

    1982-01-01

    Twenty-four men were randomly assigned to four equal groups matched in terms of their Coriolis Sickness Susceptibility Index (CSSI). Two groups of subjects were highly susceptible to motion sickness, and two groups were moderately susceptible. All subjects were given six C551 tests at 5-d intervals. Treatment Groups I (highly susceptible) and II (moderately susceptible) were taught to control their autonomic responses, using a training method called autogenic-feedback training (AFT) before the third, fourth, and fifth CSSI tests. Control groups III (highly susceptible) and IV (moderately susceptible) received no treatment. Results showed that both treatment groups significantly improved performance on CSSI tests after training; neither of the control groups changed significantly. Highly and moderately susceptible subjects in the two treatment groups improved at comparable rates. Highly susceptible control group subjects did not habituate across tests as readily as the moderately susceptible controls.

  3. Analysis of integrated optical waveguides: variational method and effective-index method with built-in perturbation correction.

    PubMed

    Sharma, A

    2001-06-01

    We show analytically that for the modal analysis of rectangular waveguides, the recently developed effective-index method with built-in perturbation correction is identical to the first-iteration cycle of the variational method that we had developed earlier [Opt. Quantum Electron. 12, 517 (1989)]. We also show that in a number of cases the accuracy improves considerably through iteration beyond the first cycle. PMID:11393630

  4. [A Method to Estimate Metal Abundance from Stellar Spectra Using Ca Line Index].

    PubMed

    Pan, Jing-chang; Luo, A-li; Li, Xiang-ru; Wei, Peng

    2015-09-01

    This paper presents a method to estimate stellar metallicity based on BP neural network and Ca line index. This method trains a BP ANN model from SDSS/SEGUE stellar spectra and parameters provided by SSPP. The values of Teff and the line index of Ca lines are the input of network while the [Fe/H] values are the oputput of the network. A set of samples are resampled from the set of all and then a network model is trained. The network can be used to predict the stellar metallicity from low-resolution spsectra. The experiment shows that the proposed method can accurately and effectively measure the [Fe/H] from the stellar spectra. PMID:26669184

  5. Patient and provider attitudes toward genomic testing for prostate cancer susceptibility: a mixed method study

    PubMed Central

    2013-01-01

    Background The strong association between family history and prostate cancer (PCa) suggests a significant genetic contribution, yet specific highly penetrant PCa susceptibility genes have not been identified. Certain single-nucleotide-polymorphisms have been found to correlate with PCa risk; however uncertainty remains regarding their clinical utility and how to best incorporate this information into clinical decision-making. Genetic testing is available directly to consumers and both patients and healthcare providers are becoming more aware of this technology. Purchasing online allows patients to bypass their healthcare provider yet patients may have difficulty interpreting test results and providers may be called upon to interpret results. Determining optimal ways to educate both patients and providers, and strategies for appropriately incorporating this information into clinical decision-making are needed. Methods A mixed-method study was conducted in Utah between October 2011 and December 2011. Eleven focus group discussions were held and surveys were administered to 23 first-degree relatives of PCa patients living in Utah and 24 primary-care physicians and urologists practicing in Utah to present specific information about these assessments and determine knowledge and attitudes regarding health implications of using these assessments. Results Data was independently coded by two researchers (relative Kappa = .88; provider Kappa = .77) and analyzed using a grounded theory approach. Results indicated differences in attitudes and behavioral intentions between patient and provider. Despite the test’s limitations relatives indicated interest in genetic testing (52%) while most providers indicated they would not recommend the test for their patients (79%). Relatives expected providers to interpret genetic test results and use results to provide personalized healthcare recommendations while the majority of providers did not think the information would be useful in

  6. Antimicrobial susceptibility of rapidly growing mycobacteria using the rapid colorimetric method.

    PubMed

    Ramis, I B; Cnockaert, M; von Groll, A; Nogueira, C L; Leão, S C; Andre, E; Simon, A; Palomino, J C; da Silva, P E A; Vandamme, P; Martin, A

    2015-07-01

    Drug susceptibility testing (DST) of rapidly growing mycobacteria (RGM) are recommended for guiding the antimicrobial therapy. We have evaluated the use of resazurin in Mueller-Hinton medium (MHR) for MIC determination of RGM and compared the results with those obtained with the reference standard broth microdilution in Mueller-Hinton (MH) and with the resazurin microtiter assay (REMA) in 7H9 broth. The MIC of eight drugs: amikacin (AMI), cefoxitin (FOX), ciprofloxacin (CIP), clarithromycin (CLA), doxycycline (DOX), linezolid (LZD), moxifloxacin (MXF) and trimethoprim-sulfamethoxazole (TMP-SMX) were evaluated against 76 RGM (18 species) using three methods (MH, MHR, and REMA) in a 96-well plate format incubated at 37 °C over 3-5 days. Results obtained in the MH plates were interpreted by the appearance of turbidity at the bottom of the well before adding the resazurin. MHR and 7H9-REMA plates were read by visual observation for a change in color from blue to pink. The majority of results were obtained at day 5 for MH and 1 day after for MHR and 7H9-REMA. However, the preliminary experiment on time to positivity results using the reference strain showed that the resazurin can be added to the MH at day 2 to produce the results at day 3, but future studies with large sets of strains are required to confirm this suggestion. A high level of agreement (kappa 1.000-0.884) was obtained between the MH and the MHR. Comparison of results obtained with 7H9-REMA, on the other hand, revealed several discrepancies and a lower level of agreement (kappa 1.000-0.111). The majority of the strains were resistant to DOX and TMP-SMX, and the most active antimicrobials for RGM were AMI and FOX. In the present study, MHR represented an excellent alternative for MIC determination of RGM. The results could be read reliably, more easily, and more quickly than with the classical MH method. PMID:25820290

  7. In Vitro Susceptibility of Candida Species to Four Antifungal Agents Assessed by the Reference Broth Microdilution Method

    PubMed Central

    Eksi, Fahriye; Gayyurhan, Efgan Dogan; Balci, Iclal

    2013-01-01

    This study was performed to determine the distribution of Candida species isolated from the blood cultures of the patients hospitalized in our hospital and to investigate their antifungal susceptibility. Candida strains were identified at species level by using classical methods and API ID 32C (bioMerieux, France) identification kits. The susceptibility of the strains to amphotericin B, fluconazole, voriconazole, and caspofungin was evaluated by using the reference broth microdilution method in document M27-A3 of the Clinical and Laboratory Standards Institute. Of the 111 Candida strains isolated, 47.7% were identified as C. albicans and 52.3% as non-albicans Candida strains. The MIC ranges were 0.03–1 μg/mL for amphotericin B, 0.125–≥64 μg/mL for fluconazole, 0.03–16 μg/mL for voriconazole, and 0.015–0.25 μg/mL for caspofungin. All Candida strains were susceptible to amphotericin B and caspofungin. 10.8% isolates were resistant to fluconazole and 8.1% isolates were dose-dependent susceptible. While 0.9% isolate was resistant to voriconazole, 0.9% isolate was dose-dependent susceptible. In our study, C. albicans and C. parapsilosis were the most frequently encountered agents of candidemia and it was detected that voriconazole with a low resistance rate might also be used with confidence in the treatment of infections occurring with these agents, primarily besides amphotericin B and caspofungin. PMID:24250260

  8. Debris flow susceptibility mapping using a qualitative heuristic method and Flow-R along the Yukon Alaska Highway Corridor, Canada

    NASA Astrophysics Data System (ADS)

    Blais-Stevens, A.; Behnia, P.

    2016-02-01

    This research activity aimed at reducing risk to infrastructure, such as a proposed pipeline route roughly parallel to the Yukon Alaska Highway Corridor (YAHC), by filling geoscience knowledge gaps in geohazards. Hence, the Geological Survey of Canada compiled an inventory of landslides including debris flow deposits, which were subsequently used to validate two different debris flow susceptibility models. A qualitative heuristic debris flow susceptibility model was produced for the northern region of the YAHC, from Kluane Lake to the Alaska border, by integrating data layers with assigned weights and class ratings. These were slope angle, slope aspect, surficial geology, plan curvature, and proximity to drainage system. Validation of the model was carried out by calculating a success rate curve which revealed a good correlation with the susceptibility model and the debris flow deposit inventory compiled from air photos, high-resolution satellite imagery, and field verification. In addition, the quantitative Flow-R method was tested in order to define the potential source and debris flow susceptibility for the southern region of Kluane Lake, an area where documented debris flow events have blocked the highway in the past (e.g. 1988). Trial and error calculations were required for this method because there was not detailed information on the debris flows for the YAHC to allow us to define threshold values for some parameters when calculating source areas, spreading, and runout distance. Nevertheless, correlation with known documented events helped define these parameters and produce a map that captures most of the known events and displays debris flow susceptibility in other, usually smaller, steep channels that had not been previously documented.

  9. In vitro susceptibility tests for cationic peptides: comparison of broth microdilution methods for bacteria that grow aerobically.

    PubMed

    Giacometti, A; Cirioni, O; Barchiesi, F; Del Prete, M S; Fortuna, M; Caselli, F; Scalise, G

    2000-06-01

    The in vitro susceptibilities of 90 clinical isolates of gram-positive and gram-negative aerobic bacteria to six cationic peptides, buforin II, cecropin P1, indolicidin, magainin II, nisin, and ranalexin, were evaluated by two broth microdilution methods. The first method was performed according to the procedures outlined by the National Committee for Clinical Laboratory Standards for bacteria that grow aerobically, while the second was performed according to the procedures recently proposed by the R. E. W. Hancock laboratory for testing antimicrobial peptides. Overall, the first method produced MICs two- and fourfold higher than the second method. PMID:10817731

  10. Interference method for monitoring the refractive index and the thickness of transparent films during deposition

    NASA Astrophysics Data System (ADS)

    Alius, H.; Schmidt, R.

    1990-04-01

    An interferometric method is described for simultaneous measurement of the refractive index and the thickness of transparent isotropic films during the deposition process. Two laser beams are focused impinging at two different angles onto the film. The intensity of the beams reflected from the growing film shows minima and maxima, which are counted and evaluated to determine the refractive index n and the thickness d of the film in the range of some 100 nm up to several micrometers using 633-nm laser light. n and d can be determined within an accuracy better than 1%, if the thickness is larger than three times the vacuum wavelength of the laser. The measurements are well in accordance with calculations of the intensity modulation. The method can easily be extended to multilayer systems.

  11. [Research on Accuracy and Stability of Inversing Vegetation Chlorophyll Content by Spectral Index Method].

    PubMed

    Jiang, Hai-ling; Yang, Hang; Chen, Xiao-ping; Wang, Shu-dong; Li, Xue-ke; Liu, Kai; Cen, Yi

    2015-04-01

    Spectral index method was widely applied to the inversion of crop chlorophyll content. In the present study, PSR3500 spectrometer and SPAD-502 chlorophyll fluorometer were used to acquire the spectrum and relative chlorophyll content (SPAD value) of winter wheat leaves on May 2nd 2013 when it was at the jointing stage of winter wheat. Then the measured spectra were resampled to simulate TM multispectral data and Hyperion hyperspectral data respectively, using the Gaussian spectral response function. We chose four typical spectral indices including normalized difference vegetation index (NDVD, triangle vegetation index (TVI), the ratio of modified transformed chlorophyll absorption ratio index (MCARI) to optimized soil adjusted vegetation index (OSAVI) (MCARI/OSAVI) and vegetation index based on universal pattern decomposition (VIUPD), which were constructed with the feature bands sensitive to the vegetation chlorophyll. After calculating these spectral indices based on the resampling TM and Hyperion data, the regression equation between spectral indices and chlorophyll content was established. For TM, the result indicates that VIUPD has the best correlation with chlorophyll (R2 = 0.819 7) followed by NDVI (R2 = 0.791 8), while MCARI/OSAVI and TVI also show a good correlation with R2 higher than 0.5. For the simulated Hyperion data, VIUPD again ranks first with R2 = 0.817 1, followed by MCARI/OSAVI (R2 = 0.658 6), while NDVI and TVI show very low values with R2 less than 0.2. It was demonstrated that VIUPD has the best accuracy and stability to estimate chlorophyll of winter wheat whether using simulated TM data or Hyperion data, which reaffirms that VIUPD is comparatively sensor independent. The chlorophyll estimation accuracy and stability of MCARI/OSAVI also works well, partly because OSAVI could reduce the influence of backgrounds. Two broadband spectral indices NDVI and TVI are weak for the chlorophyll estimation of simulated Hyperion data mainly because of

  12. Aquifer sensitivity to pesticide leaching: Testing a soils and hydrogeologic index method

    USGS Publications Warehouse

    Mehnert, E.; Keefer, D.A.; Dey, W.S.; Wehrmann, H.A.; Wilson, S.D.; Ray, C.

    2005-01-01

    For years, researchers have sought index and other methods to predict aquifer sensitivity and vulnerability to nonpoint pesticide contamination. In 1995, an index method and map were developed to define aquifer sensitivity to pesticide leaching based on a combination of soil and hydrogeologic factors. The soil factor incorporated three soil properties: hydraulic conductivity, amount of organic matter within individual soil layers, and drainage class. These properties were obtained from a digital soil association map. The hydrogeologic factor was depth to uppermost aquifer material. To test this index method, a shallow ground water monitoring well network was designed, installed, and sampled in Illinois. The monitoring wells had a median depth of 7.6 m and were located adjacent to corn and soybean fields where the only known sources of pesticides were those used in normal agricultural production. From September 1998 through February 2001, 159 monitoring wells were sampled for 14 pesticides but no pesticide metabolites. Samples were collected and analyzed to assess the distribution of pesticide occurrence across three units of aquifer sensitivity. Pesticides were detected in 18% of all samples and nearly uniformly from samples from the three units of aquifer sensitivity. The new index method did not predict pesticide occurrence because occurrence was not dependent on the combined soil and hydrogeologic factors. However, pesticide occurrence was dependent on the tested hydrogeologic factor and was three times higher in areas where the depth to the uppermost aquifer was <6 m than in areas where the depth to the uppermost aquifer was 6 to <15 m. Copyright ?? 2005 National Ground Water Association.

  13. Methods to retrieve the complex refractive index of aquatic suspended particles: going beyond simple shapes

    NASA Astrophysics Data System (ADS)

    Sánchez, Albert-Miquel; Piera, Jaume

    2016-07-01

    The scattering properties of aquatic suspended particles have many optical applications. Several data inversion methods have been proposed to estimate important features of particles, such as their size distribution or their refractive index. Most of the proposed methods are based on the Lorenz-Mie theory to solve Maxwell's equations, where particles are considered homogeneous spheres. A generalization that allows consideration of more complex-shaped particles is the T-matrix method. Although this approach imposes some geometrical restrictions (particles must be rotationally symmetrical) it is applicable to many life forms of phytoplankton. In this paper, three different scenarios are considered in order to compare the performance of several inversion methods for retrieving refractive indices. The error associated with each method is discussed and analyzed. The results suggest that inverse methods using the T-matrix approach are useful to accurately retrieve the refractive indices of particles with complex shapes, such as for many phytoplankton organisms.

  14. Evaluation of a Scanner-Assisted Colorimetric MIC Method for Susceptibility Testing of Gram-Negative Fermentative Bacteria

    PubMed Central

    Rahman, Mokhlasur; Kühn, Inger; Rahman, Motiur; Olsson-Liljequist, Barbro; Möllby, Roland

    2004-01-01

    We describe the ScanMIC method, a colorimetric MIC method for susceptibility testing of gram-negative fermentative bacteria. The method is a slight modification of the National Committee for Clinical Laboratory Standards (NCCLS) recommended broth microdilution method that uses a redox indicator 2,3,5-triphenyltetrazolium chloride (TTC) to enhance the estimate of bacterial growth inhibition in a microplate and a flatbed scanner to capture the microplate image. In-house software was developed to transform the microplate image into numerical values based on the amount of bacterial growth and to generate the MICs automatically. The choice of indicator was based on its low toxicity and ease of reading by scanner. We compared the ScanMIC method to the NCCLS recommended broth microdilution method with 197 coliform strains against seven antibacterial agents. The interpretative categorical agreement was obtained in 92.4% of the assays, and the agreement for MIC differences (within ±1 log2 dilution) was obtained in 96% for ScanMIC versus broth microdilution and 97% for a two-step incubation colorimetric broth microdilution versus the broth microdilution method. The method was found to be labor-saving, not to require any initial investment, and to show reliable results. Thus, the ScanMIC method could be useful for epidemiological surveys that include susceptibility testing of bacteria. PMID:15066837

  15. Variability of β-lactam susceptibility testing for Streptococcus pneumoniae using 4 commercial test methods and broth microdilution.

    PubMed

    Charles, Marthe K; Berenger, Byron M; Turnbull, LeeAnn; Rennie, Robert; Fuller, Jeff

    2016-03-01

    Limited data are available that verify the performance of commercial susceptibility methods for Streptococcus pneumoniae following the 2008 Clinical and Laboratory Standards Institute revision of the β-lactam breakpoints. We compared the performance of Etest, M.I.C. Evaluator (M.I.C.E), Vitek, and Sensititre systems to broth microdilution for S. pneumoniae susceptibility testing of penicillin, ceftriaxone, meropenem, and amoxicillin. Essential agreement was ≥90% for the majority of the β-lactams and methods tested, particularly for penicillin and ceftriaxone. Categorical agreements (CAs) for penicillin using meningeal and nonmeningeal breakpoints were ≥90%; CAs using penicillin oral breakpoints were 84-89%. Ceftriaxone CAs using nonmeningeal and meningeal breakpoints were 68-88% for Etest, M.I.C.E., and Vitek2 with 6-12% very major errors (VMEs) using meningeal breakpoints. Sensititre CAs for ceftriaxone, amoxicillin, and meropenem were ≥90% with no VMEs. In the context of the current guidelines, there exists considerable method-dependent variability in the susceptibility of S. pneumoniae to β-lactams. PMID:26707068

  16. Results Obtained with Various Antifungal Susceptibility Testing Methods Do Not Predict Early Clinical Outcome in Patients with Cryptococcosis

    PubMed Central

    Dannaoui, E.; Abdul, M.; Arpin, M.; Michel-Nguyen, A.; Piens, M. A.; Favel, A.; Lortholary, O.; Dromer, F.

    2006-01-01

    The in vitro susceptibilities of Cryptococcus neoformans isolates from consecutive human immunodeficiency virus-positive and -negative patients to the antifungal agents fluconazole, amphotericin B, and flucytosine were determined by different techniques, including the CLSI method, Etest, and broth microdilution in yeast nitrogen base (YNB) medium, during a multicenter prospective study in France. The relationship between the in vitro data and the clinical outcome 2 weeks after the initiation of antifungal therapy was assessed. In addition, the correlation between the strain serotype and the in vitro activities of the antifungals was determined, and the susceptibility results obtained with the different techniques were also compared. Thirty-seven patients received a combination of amphotericin B with flucytosine as first-line therapy, 22 were treated with amphotericin B alone, and 15 received fluconazole alone. Whatever the antifungal tested, there was no trend toward higher MICs for strains isolated from patients who failed to respond to a given therapy compared to those from patients who did not with either the CLSI method, Etest, or broth microdilution in YNB medium. The MICs obtained by the CLSI or Etest method were significantly lower for serotype D strains than for serotype A strains for both fluconazole and amphotericin B, while flucytosine MICs were not different according to serotype. These findings suggest that the in vitro antifungal susceptibility of C. neoformans, as determined with the techniques used, is not able to predict the early clinical outcome in patients with cryptococcosis. PMID:16801427

  17. Development of an Accelerated Test Method for the Determination of Susceptibility to Atmospheric Corrosion

    NASA Technical Reports Server (NTRS)

    Ambrose, John R.

    1991-01-01

    The theoretical rationale is presented for use of a repetitive cyclic current reversal voltammetric technique for characterization of localized corrosion processes, including atmospheric corrosion. Applicability of this proposed experimental protocol is applied to characterization of susceptibility to crevice and pitting corrosion, atmospheric corrosion and stress corrosion cracking. Criteria upon which relative susceptibility is based were determined and tested using two iron based alloys commonly in use at NASA-Kennedy; A36 (a low carbon steel) and 4130 (a low alloy steel). Practicality of the procedure was demonstrated by measuring changes in anodic polarization behavior during high frequency current reversal cycles of 25 cycles per second with 1 mA/sq cm current density amplitude in solutions containing Cl anions. The results demonstrated that, due to excessive polarization which affects conductivity of barrier corrosion product layers, A36 was less resistant to atmospheric corrosion than its 4130 counterpart; behavior which was also demonstrated during exposure tests.

  18. The Mid-term Forecast Method of Solar Radiation Index {F}_{10.7}

    NASA Astrophysics Data System (ADS)

    Wang, H. B.; Xiong, J. N.; Zhao, C. Y.

    2014-07-01

    In the low earth orbit satellite's orbit computation, the solar radiation index F_{10.7} is an important parameter, which is usually used to describe the solar activity's effect on the thermosphere density and the orbit perturbation. So the accuracy of index F_{10.7} will affect the precision of orbit prediction. In this paper, based on the characteristics of the solar 27-day short-term activity, we bring up a forecast method of F_{10.7} which can use the historical indices of the past 135 days to predict the solar radiation indices in the next 54 days. That is to say, the method is able to forecast the variations of solar radiation for about two rotation-cycles in the future. In this paper, we compare this method with those widely-used methods. The detail results are as follows: (1) This paper's method is observably better than the traditional triangle function method; (2) In the short-term forecast (7 days) , this paper's method is little better than the method developed by Space Weather Prediction Center in America, since the root mean square could be reduced by about 19% when using this paper's method; (3) In the mid-termforecast (2 7 days), the accuracy of this paper's method is almost equal to the 54-order self-regression method which is used widely in our country. However, fewer parameters and observation data are needed in this paper's method, leading to the more convenient application in orbit computation. Moreover, on the 54th day the correlation coefficient between the prediction and actual index is still greater than 0.92, implying that the method can keep stable in mid-term forecast. All in all, the advantage of this paper's method is that it could use fewer historical indices to predict the mid-term solar radiation independent of extra solar real-time observation, and it is very helpful to the orbit short- and mid-term predictions in some space flight missions.

  19. Novel method to assess antiretroviral target trough concentrations using in vitro susceptibility data.

    PubMed

    Acosta, Edward P; Limoli, Kay L; Trinh, Lan; Parkin, Neil T; King, Jennifer R; Weidler, Jodi M; Ofotokun, Ighovwerha; Petropoulos, Christos J

    2012-11-01

    Durable suppression of HIV-1 replication requires the establishment of antiretroviral drug concentrations that exceed the susceptibility of the virus strain(s) infecting the patient. Minimum plasma drug concentrations (C(trough)) are correlated with response, but determination of target C(trough) values is hindered by a paucity of in vivo concentration-response data. In the absence of these data, in vitro susceptibility measurements, adjusted for serum protein binding, can provide estimations of suppressive in vivo drug concentrations. We derived serum protein binding correction factors (PBCF) for protease inhibitors, nonnucleoside reverse transcriptase inhibitors, and an integrase inhibitor by measuring the effect of a range of human serum concentrations on in vitro drug susceptibility measured with the PhenoSense HIV assay. PBCFs corresponding to 100% HS were extrapolated using linear regression and ranged from 1.4 for nevirapine to 77 for nelfinavir. Using the mean 95% inhibitory concentration (IC(95)) for ≥1,200 drug-susceptible viruses, we calculated protein-bound IC(95) (PBIC(95)) values. PBIC(95) values were concordant with the minimum effective C(trough) values that were established in well-designed pharmacodynamic studies (e.g., indinavir, saquinavir, and amprenavir). In other cases, the PBIC(95) values were notably lower (e.g., darunavir, efavirenz, and nevirapine) or higher (nelfinavir and etravirine) than existing target recommendations. The establishment of PBIC(95) values as described here provides a convenient and standardized approach for estimation of the minimum drug exposure that is required to maintain viral suppression and prevent the emergence of drug-resistant variants, particularly when in vivo concentration-response relationships are lacking. PMID:22964257

  20. Space Systems - Safety and Compatibility of Materials - Method to Determine the Ignition Susceptibility of Materials or Components to Particle Impact

    NASA Technical Reports Server (NTRS)

    Hirsch, David B.

    2011-01-01

    The scope of this International Technical Specification is to provide a method to determine the ignition susceptibility of materials and components to particle impact. The method can be used to determine the conditions at which ignition and consumption of a specimen material occurs when impacted by single or multiple particles entrained in a flow of gaseous oxygen (GOX). Alternatively, the method can be used to determine if a specific material or component is subject to ignition and sustained combustion in a given flow environment when impacted by single or multiple particles entrained in a flow of GOX.

  1. ABCD matrix of the human lens gradient-index profile: applicability of the calculation methods.

    PubMed

    Díaz, José Antonio

    2008-01-10

    The applicability of different approximate methods proposed to determine the paraxial properties of the gradient-index (GRIN) distribution resembling that of the human lens, by means of the system ABCD matrix, is tested. Thus, the parabolic-ray-path approximation has been extended to provide the ABCD matrix of a slab lens comprised of a rotationally GRIN medium. The results show that this method has good numerical stability, and it is also the easiest one in determining the Gaussian constants of the human lens GRIN profile. PMID:18188201

  2. A survey on palette reordering methods for improving the compression of color-indexed images.

    PubMed

    Pinho, Armando J; Neves, António J R

    2004-11-01

    Palette reordering is a well-known and very effective approach for improving the compression of color-indexed images. In this paper, we provide a survey of palette reordering methods, and we give experimental results comparing the ability of seven of them in improving the compression efficiency of JPEG-LS and lossless JPEG 2000. We concluded that the pairwise merging heuristic proposed by Memon et al. is the most effective, but also the most computationally demanding. Moreover, we found that the second most effective method is a modified version of Zeng's reordering technique, which was 3%-5% worse than pairwise merging, but much faster. PMID:15540450

  3. I like your GRIN: Deign methods for gradient-index progressive addition lenses

    NASA Astrophysics Data System (ADS)

    Fischer, David J.; Moore, Duncan T.

    2002-12-01

    Progressive addition lenses (PALs) are vision correction lenses with a continuous change in power, used to treat the physical condition presbyopia. These lenses are currently fabricated using non-rotationally symmetric surfaces to achieve the focal power transition and aberration control. In this research, we consider the use of Gradient-Index (GRIN) designs for providing both power progression and aberration control. The use of B-Spline curves for GRIN representation is explained. Design methods and simulation results for GRIN PALs are presented. Possible uses for the design methods with other lenses, such as unifocal lenses and axicons, are also discussed.

  4. Grouping Method for Neighbor Objects of Moving Object Using Hash Index

    NASA Astrophysics Data System (ADS)

    Lee, B.; Kim, J.; Yu, K.

    2015-10-01

    A location-based social network (LBSNS) is a social network service (SNS) that is based on a user's location, unlike SNS, and facilitates additional activities like neighbour-user search and group formation in real time. This research examined the efficiency of a real-time grouping method for extracted neighbour objects on a WMTS (Web Map Tile Service) for which a hash index was used. As a result, the suggested method is not different from buffering a neighbour area according to the average number of returned data per 1 km2, and the required time is shorter than that of buffering.

  5. A Multi-Index Integrated Change detection method for updating the National Land Cover Database

    USGS Publications Warehouse

    Jin, Suming; Yang, Limin; Xian, George Z.; Danielson, Patrick; Homer, Collin

    2010-01-01

    Land cover change is typically captured by comparing two or more dates of imagery and associating spectral change with true thematic change. A new change detection method, Multi-Index Integrated Change (MIIC), has been developed to capture a full range of land cover disturbance patterns for updating the National Land Cover Database (NLCD). Specific indices typically specialize in identifying only certain types of disturbances; for example, the Normalized Burn Ratio (NBR) has been widely used for monitoring fire disturbance. Recognizing the potential complementary nature of multiple indices, we integrated four indices into one model to more accurately detect true change between two NLCD time periods. The four indices are NBR, Normalized Difference Vegetation Index (NDVI), Change Vector (CV), and a newly developed index called the Relative Change Vector (RCV). The model is designed to provide both change location and change direction (e.g. biomass increase or biomass decrease). The integrated change model has been tested on five image pairs from different regions exhibiting a variety of disturbance types. Compared with a simple change vector method, MIIC can better capture the desired change without introducing additional commission errors. The model is particularly accurate at detecting forest disturbances, such as forest harvest, forest fire, and forest regeneration. Agreement between the initial change map areas derived from MIIC and the retained final land cover type change areas will be showcased from the pilot test sites.

  6. A Multi-Index Integrated Change Detection Method for Updating the National Land Cover Database

    NASA Astrophysics Data System (ADS)

    Jin, S.; Yang, L.; Xian, G. Z.; Danielson, P.; Homer, C.

    2010-12-01

    Land cover change is typically captured by comparing two or more dates of imagery and associating spectral change with true thematic change. A new change detection method, Multi-Index Integrated Change (MIIC), has been developed to capture a full range of land cover disturbance patterns for updating the National Land Cover Database (NLCD). Specific indices typically specialize in identifying only certain types of disturbances; for example, the Normalized Burn Ratio (NBR) has been widely used for monitoring fire disturbance. Recognizing the potential complementary nature of multiple indices, we integrated four indices into one model to more accurately detect true change between two NLCD time periods. The four indices are NBR, Normalized Difference Vegetation Index (NDVI), Change Vector (CV), and a newly developed index called the Relative Change Vector (RCV). The model is designed to provide both change location and change direction (e.g. biomass increase or biomass decrease). The integrated change model has been tested on five image pairs from different regions exhibiting a variety of disturbance types. Compared with a simple change vector method, MIIC can better capture the desired change without introducing additional commission errors. The model is particularly accurate at detecting forest disturbances, such as forest harvest, forest fire, and forest regeneration. Agreement between the initial change map areas derived from MIIC and the retained final land cover type change areas will be showcased from the pilot test sites.

  7. Development and testing of method for assessing and mapping agricultural areas susceptible to atrazine leaching in the state of Washington

    USGS Publications Warehouse

    Voss, Frank D.

    2003-01-01

    In a joint effort by the Washington State Department of Agriculture, the Washington Department of Ecology, and the U.S. Geological Survey, the Environmental Protection Agency's Pesticide Root Zone Model and a Geographic Information System were used to develop and test a method for screening and mapping the susceptibility of ground water in agricultural areas to pesticide contamination. The objective was to produce a map that would be used by the Washington State Department of Agriculture to allocate resources for monitoring pesticide levels in ground water. The method was tested by producing a map showing susceptibility to leaching of the pesticide atrazine for the Columbia Basin Irrigation Project, which encompasses an area of intensive agriculture in eastern Washington. The reliability of the atrazine map was assessed by using statistical procedures to determine whether the median of the percentage of atrazine simulated to leach below the root zone in wells where atrazine was detected was statistically greater than the median percentage at wells where atrazine was not detected (at or above 0.001 microgram per liter) in 134 wells sampled by the U.S. Geological Survey. A statistical difference in medians was not found when all 134 wells were compared. However, a statistical difference was found in medians for two subsets of the 134 wells that were used in land-use studies (studies examining the quality of ground water beneath specific crops). The statistical results from wells from the land-use studies indicate that the model potentially can be used to map the relative susceptibility of agricultural areas to atrazine leaching. However, the distinction between areas of high and low susceptibility may not yet be sufficient to use the method for allocating resources to monitor water quality. Several options are offered for improving the reliability of future simulations.

  8. R-Index Measure of Microencapsulated Tributyrin in Gamma-Cyclodextrin Influenced by Drying Method.

    PubMed

    Donovan, Joseph D; Lee, Soo-Yeun; Lee, Youngsoo

    2016-09-01

    Microencapsulation is commonly used in the food industry for a variety of purposes including added ingredient functionally and taste-masking for those ingredients with negative sensory qualities. Tributyrin (TB), a source intestinally-essential butyric acid, possesses negative aroma (cheesy, fecal) and taste (bitter) qualities. This has significantly limited its use in food applications for the potential improvement of intestinal health. Utilizing spray drying and low-temperature oven drying, microcapsules containing TB were produced using whey (WPI), WPI and inulin, and gamma-cyclodextrin (GCD). To determine how microcapsule formulation and drying method affected the perception of TB relative to a control, microencapsulated and free TB were added to an infant formula system and evaluated using the rating method to determine R-index measures. Pooled R-index measures (α = 0.01, 2-tailed, and n = 170) indicated that the only microcapsule not significantly different from the control (R-index below 57.95%) was the GCD and TB oven dried (GCT OD) microcapsule. All other WPI, WPI-inulin, and GCD and TB spray-dried (GCT SD) microcapsules were all significantly different from the control. Average individual R-index results indicated that all microcapsules in infant formula, except for GCT OD, were significantly different (P < 0.01) from the control formula but not from free TB. Spray drying may create microcapsules with surface TB and disturb the GCD-TB complex, allowing free, and surface TB to be perceived by the panelists. The GCT OD microcapsule has the potential to be used for the potential oral treatment of intestinal disorders in functional food applications without the negative sensory qualities of TB. PMID:27527112

  9. In vitro antimicrobial susceptibility testing of Borrelia burgdorferi: a microdilution MIC method and time-kill studies.

    PubMed Central

    Dever, L L; Jorgensen, J H; Barbour, A G

    1992-01-01

    The susceptibility of Borrelia burgdorferi, the causative agent of Lyme borreliosis, to various antimicrobial agents varies widely among published studies. These differences are probably due in part to variations in susceptibility testing techniques and growth endpoint determinations. We developed a microdilution method for determining the MICs of antibiotics against B. burgdorferi. The method incorporated BSK II medium, a final inoculum of 10(6) cells per ml, and a 72-h incubation period and was found to be simple and highly reproducible. A variety of antibiotics and strains of B. burgdorferi and one strain of Borrelia hermsii were examined by this method. MICs of penicillin, ceftriaxone, and erythromycin for the B31 strain of B. burgdorferi were 0.06, 0.03, and 0.03 microgram/ml, respectively. We compared the MICs obtained by the microdilution method with those obtained by a macrodilution method using similar criteria for endpoint determinations and found the values obtained by both methods to be in close agreement. To further investigate the bactericidal activities of penicillin, ceftriaxone, and erythromycin against strain B31, we used subsurface plating to determine MBCs and we also performed time-kill studies. The MBCs of penicillin, ceftriaxone, and erythromycin were 0.125, 0.03, and 0.06 micrograms/ml, respectively. Time-kill curves demonstrated a greater than or equal to 3-log10-unit killing after 72 h with penicillin, ceftriaxone, and erythromycin; ceftriaxone provided the greatest reduction in CFU. The described methods offer a more standardized and objective approach to susceptibility testing of B. burgdorferi. Images PMID:1400969

  10. A rapid method for the determination of microbial susceptibility using the firefly luciferase assay for adenosine triphosphate (ATP)

    NASA Technical Reports Server (NTRS)

    Vellend, H.; Tuttle, S. A.; Barza, M.; Weinstein, L.; Picciolo, G. L.; Chappelle, E. W.

    1975-01-01

    Luciferase assay for adenosine triphosphate (ATP) was optimized for pure bacteria in broth in order to evaluate if changes in bacterial ATP content could be used as a rapid measure of antibiotic effect on microorganisms. Broth cultures of log phase bacteria were incubated at 310 K (37 C) for 2.5 hours at antimicrobial concentrations which resulted in the best discrimination between sensitive and resistant strains. Eighty-seven strains of 11 bacterial species were studied for their susceptibility to 12 commonly used antimicrobial agents: ampicillin, Penicillin G, nafcillin, carbenicillin, cephalothin, tetracycline, erythromycin, clindamycin, gentamicin, nitrofurantoin, colistin, and chloramplenicol. The major advantage of the ATP system over existing methods of rapid microbial susceptibility testing is that the assay can be made specific for bacterial ATP.

  11. A Simple Accurate Alternative to the Minimum-Deviation Method for the Determination of the Refractive Index of a Prism.

    ERIC Educational Resources Information Center

    Waldenstrom, S.; Naqvi, K. Razi

    1978-01-01

    Proposes an alternative to the classical minimum-deviation method for determining the refractive index of a prism. This new "fixed angle of incidence method" may find applications in research. (Author/GA)

  12. Development of Similar Broth Microdilution Methods to Determine the Antimicrobial Susceptibility of Flavobacterium columnare and F. psychrophilum.

    PubMed

    Gieseker, Charles M; Crosby, Tina C; Mayer, Tamara D; Bodeis, Sonya M; Stine, Cynthia B

    2016-03-01

    Flavobacterium columnare and F. psychrophilum are major fish pathogens that cause diseases that may require antimicrobial therapy. Choice of appropriate treatment is dependent upon determining the antimicrobial susceptibility of isolates. Therefore we optimized methods for broth microdilution testing of F. columnare and F. psychrophilum to facilitate standardizing an antimicrobial susceptibility test. We developed adaptations to make reproducible broth inoculums and confirmed the proper incubation time and media composition. We tested the stability of potential quality-control bacteria and compared test results between different operators. Log phase occurred at 48 h for F. columnare and 72-96 h for F. psychrophilum, confirming the test should be incubated at 28°C for approximately 48 h and at 18°C for approximately 96 h, respectively. The most consistent susceptibility results were achieved with plain, 4-g/L, dilute Mueller-Hinton broth supplemented with dilute calcium and magnesium. Supplementing the broth with horse serum did not improve growth. The quality-control strains, Escherichia coli ATCC 25922 and Aeromonas salmonicida subsp. salmonicida ATCC 33658, yielded stable minimal inhibitory concentrations (MIC) against all seven antimicrobials tested after 30 passes at 28°C and 15 passes at 18°C. In comparison tests, most MICs of the isolates agreed 100% within one drug dilution for ampicillin, florfenicol, and oxytetracycline. The agreement was lower with the ormetoprim-sulfdimethoxine combination, but there was at least 75% agreement for all but one isolate. These experiments have provided methods to help standardize antimicrobial susceptibility testing of these nutritionally fastidious aquatic bacteria. Received June 24, 2015; accepted October 2, 2015. PMID:26949840

  13. Occlusion culling and calculation for a computer generated hologram using spatial frequency index method

    NASA Astrophysics Data System (ADS)

    Zhao, Kai; Huang, Yingqing; Yan, Xingpeng; Jiang, Xiaoyu

    2015-10-01

    A spatial frequency index method is proposed to cull occlusion and generate a hologram. Object points with the same spatial frequency are put into a set for their mutual occlusion. The hidden surfaces of the three-dimensional (3D) scene are quickly removed through culling the object points that are furthest from the hologram plane in the set. The phases of plane wave, which are only interrelated with the spatial frequencies, are precomputed and stored in a table. According to the spatial frequency of the object points, the phases of plane wave for generating fringes are obtained directly from the table. Three 3D scenes are chosen to verify the spatial frequency index method. Both numerical simulation and optical reconstruction are performed. Experimental results demonstrate that the proposed method can cull the hidden surfaces of the 3D scene correctly. The occlusion effect of the 3D scene can be well reproduced. The computational speed is better than that obtained using conventional methods but is still time-consuming.

  14. Bend insensitive graded index multimode polymer optical waveguides fabricated using the Mosquito method

    NASA Astrophysics Data System (ADS)

    Takahashi, Asami; Ishigure, Takaaki

    2015-02-01

    We fabricate low-loss graded index (GI) circular core multimode polymer optical waveguides with 90o bending and demonstrate low bending loss even if the bend radius is as small as 1 mm. In the several fabrication methods for GI-core polymer waveguides already proposed, we adopt the "Mosquito method" that utilize a microdispenser because the Mosquito method makes it possible to fabricate waveguides directly on board at desired places on a printed circuit board, and to draw various patterns of cores including curves. However, in the waveguides including such curved cores, the additional transmission loss due to the bending (bending loss) is a concern. Thus, we characterize the fabricated GI-core polymer waveguides with bending: using two kinds of cladding monomer with different refractive indexes for fabricating waveguides with bending. We found when the NA of waveguides was as high as 0.35, no additional loss due to bending was observed even if the bending radius is as small as 1 mm. The core diameter of the fabricated waveguides is 50 μm, and it is possible to further decrease the bending loss in the waveguides with smaller core diameter. Furthermore, utilizing the Mosquito method, we fabricate waveguides with not only horizontally curved cores but also vertically curved ones. Waveguides with vertically curved cores could make it possible to realize three-dimensionally optical wiring applicable to on-board optical interconnects.

  15. Susceptibility Testing

    MedlinePlus

    ... page helpful? Also known as: Sensitivity Testing; Drug Resistance Testing; Culture and Sensitivity; C & S; Antimicrobial Susceptibility Formal name: Bacterial and Fungal Susceptibility Testing Related tests: Urine Culture ; ...

  16. Is a New Standard Needed for Diffusion Methods for In Vitro Susceptibility Testing of Fosfomycin against Pseudomonas aeruginosa?

    PubMed Central

    Díez-Aguilar, María; Martínez-García, Laura; Morosini, María Isabel

    2015-01-01

    We analyzed fosfomycin susceptibility results in Pseudomonas aeruginosa clinical isolates obtained by MIC gradient strips and disk diffusion methods using two different inocula, 108 and 106 CFU/ml, and compared them to the agar dilution reference method. Essential and categorical agreements were 93.6% and 95%, respectively, for the 106 CFU/ml alternative inoculum, and they were 67.6% and 78.2%, respectively, for the standard inoculum (108 CFU/ml). The use of the 106 CFU/ml inoculum improves the agreement values and inhibition zone readings. PMID:26643341

  17. Resazurin Microtiter Assay Plate Testing of Mycobacterium tuberculosis Susceptibilities to Second-Line Drugs: Rapid, Simple, and Inexpensive Method

    PubMed Central

    Martin, Anandi; Camacho, Mirtha; Portaels, Françoise; Palomino, Juan Carlos

    2003-01-01

    The emergence of multidrug-resistant tuberculosis calls for new, rapid drug susceptibility tests. We have tested 150 Mycobacterium tuberculosis isolates against the second-line drugs ethionamide, kanamycin, capreomycin, ofloxacin, and para-aminosalicylic acid by the colorimetric resazurin microtiter assay and the proportion method. By visual reading, MICs were obtained after 8 days. A very good correlation between results by the colorimetric resazurin microtiter assay and the proportion method was obtained. The colorimetric resazurin microtiter assay is inexpensive, rapid, and simple to perform, and implementation of the assay is feasible for low-resource countries. PMID:14576129

  18. Comparative Evaluation of Colistin Susceptibility Testing Methods among Carbapenem-Nonsusceptible Klebsiella pneumoniae and Acinetobacter baumannii Clinical Isolates.

    PubMed

    Dafopoulou, Konstantina; Zarkotou, Olympia; Dimitroulia, Evangelia; Hadjichristodoulou, Christos; Gennimata, Vasiliki; Pournaras, Spyros; Tsakris, Athanasios

    2015-08-01

    We compared six colistin susceptibility testing (ST) methods on 61 carbapenem-nonsusceptible Klebsiella pneumoniae (n = 41) and Acinetobacter baumannii (n = 20) clinical isolates with provisionally elevated colistin MICs by routine ST. Colistin MICs were determined by broth microdilution (BMD), BMD with 0.002% polysorbate 80 (P80) (BMD-P80), agar dilution (AD), Etest, Vitek2, and MIC test strip (MTS). BMD was used as the reference method for comparison. The EUCAST-recommended susceptible and resistant breakpoints of ≤2 and >2 μg/ml, respectively, were applied for both K. pneumoniae and A. baumannii. The proportions of colistin-resistant strains were 95.1, 77, 96.7, 57.4, 65.6, and 98.4% by BMD, BMD-P80, AD, Etest, MTS, and Vitek2, respectively. The Etest and MTS methods produced excessive rates of very major errors (VMEs) (39.3 and 31.1%, respectively), while BMD-P80 produced 18% VMEs, AD produced 3.3% VMEs, and Vitek2 produced no VMEs. Major errors (MEs) were rather limited by all tested methods. These data show that gradient diffusion methods may lead to inappropriate colistin therapy. Clinical laboratories should consider the use of automated systems, such as Vitek2, or dilution methods for colistin ST. PMID:26014928

  19. Comparative Evaluation of Colistin Susceptibility Testing Methods among Carbapenem-Nonsusceptible Klebsiella pneumoniae and Acinetobacter baumannii Clinical Isolates

    PubMed Central

    Dafopoulou, Konstantina; Zarkotou, Olympia; Dimitroulia, Evangelia; Hadjichristodoulou, Christos; Gennimata, Vasiliki; Tsakris, Athanasios

    2015-01-01

    We compared six colistin susceptibility testing (ST) methods on 61 carbapenem-nonsusceptible Klebsiella pneumoniae (n = 41) and Acinetobacter baumannii (n = 20) clinical isolates with provisionally elevated colistin MICs by routine ST. Colistin MICs were determined by broth microdilution (BMD), BMD with 0.002% polysorbate 80 (P80) (BMD-P80), agar dilution (AD), Etest, Vitek2, and MIC test strip (MTS). BMD was used as the reference method for comparison. The EUCAST-recommended susceptible and resistant breakpoints of ≤2 and >2 μg/ml, respectively, were applied for both K. pneumoniae and A. baumannii. The proportions of colistin-resistant strains were 95.1, 77, 96.7, 57.4, 65.6, and 98.4% by BMD, BMD-P80, AD, Etest, MTS, and Vitek2, respectively. The Etest and MTS methods produced excessive rates of very major errors (VMEs) (39.3 and 31.1%, respectively), while BMD-P80 produced 18% VMEs, AD produced 3.3% VMEs, and Vitek2 produced no VMEs. Major errors (MEs) were rather limited by all tested methods. These data show that gradient diffusion methods may lead to inappropriate colistin therapy. Clinical laboratories should consider the use of automated systems, such as Vitek2, or dilution methods for colistin ST. PMID:26014928

  20. Accuracy of different methods for susceptibility testing of gentamicin with KPC carbapenemase-producing Klebsiella pneumoniae.

    PubMed

    Arena, Fabio; Giani, Tommaso; Vaggelli, Guendalina; Terenzi, Giovanni; Pecile, Patrizia; Rossolini, Gian Maria

    2015-02-01

    Performance of Vitek2, Etest, and TREK broth microdilution (BMD) panels was evaluated versus reference CLSI BMD for gentamicin susceptibility testing with 57 bloodstream isolates of KPC-producing Klebsiella pneumoniae. Compared with reference BMD, the Essential Agreement and Categorical Agreement for TREK panels, Vitek2, and Etest were 91.2%, 31.6%, and 61.4%, respectively, and 86%, 21%, and 52.6%, respectively. Four very major discrepancies occurred with Vitek2. In these 4 strains, gentamicin resistance was associated with the presence of an armA aminoglycoside resistance determinant. PMID:25533616

  1. A retrospective evaluation method for in vitro mammalian genotoxicity tests using cytotoxicity index transformation formulae.

    PubMed

    Fujita, Yurika; Kasamatsu, Toshio; Ikeda, Naohiro; Nishiyama, Naohiro; Honda, Hiroshi

    2016-01-15

    Although in vitro chromosomal aberration tests and micronucleus tests have been widely used for genotoxicity evaluation, false-positive results have been reported under strong cytotoxic conditions. To reduce false-positive results, the new Organization for Economic Co-operation and Development (OECD) test guideline (TG) recommends the use of a new cytotoxicity index, relative increase in cell count or relative population doubling (RICC/RPD), instead of the traditionally used index, relative cell count (RCC). Although the use of the RICC/RPD may result in different outcomes and require re-evaluation of tested substances, it is impractical to re-evaluate all existing data. Therefore, we established a method to estimate test results from existing RCC data. First, we developed formulae to estimate RICC/RPD from RCC without cell counts by considering cell doubling time and experiment time. Next, the accuracy of the cytotoxicity index transformation formulae was verified by comparing estimated RICC/RPD and measured RICC/RPD for 3 major chemicals associated with false-positive genotoxicity test results: ethyl acrylate, eugenol and p-nitrophenol. Moreover, 25 compounds with false-positive in vitro chromosomal aberration (CA) test results were re-evaluated to establish a retrospective evaluation method based on derived estimated RICC/RPD values. The estimated RICC/RPD values were in good agreement with the measured RICC/RPD values for every concentration and chemical, and the estimated RICC suggested the possibility that 12 chemicals (48%) with previously judged false-positive results in fact had negative results. Our method enables transformation of RCC data into RICC/RPD values with a high degree of accuracy and will facilitate comprehensive retrospective evaluation of test results. PMID:26778504

  2. Random Estimate the values of seed oil of Cucurbita maxima by refractive index method.

    PubMed

    Saxena, R B

    2010-01-01

    The crude oil having lower iodine and free fatty acids values has Aamdosha properties. These properties are present due to toxic and anti-toxic compounds. These compounds can be harmful for the special diseases and may be unsaturated, saturated, open chain etc. The adulteration can take part as catalytic action for the toxic effect for the special diseases. Toxic properties of oils are removed by different ingrediants and methods. C. maxima seed tail (mst) is used with food and medicine. The present paper deals with the study of oil by refractive index and equations. PMID:22131677

  3. Evaluation of the broth microdilution method using 2,3-diphenyl-5-thienyl-(2)-tetrazolium chloride for rapidly growing mycobacteria susceptibility testing.

    PubMed

    Lee, Sun Min; Kim, Jeong man; Jeong, Joseph; Park, Young Kil; Bai, Gill-Han; Lee, Eun Yup; Lee, Min Ki; Chang, Chulhun L

    2007-10-01

    As the incidence of nontuberculous mycobacterial infection has been increasing recently in Korea, the importance of drug susceptibility test for clinical isolates of mycobacteria has become larger. In this study we determined the antimicrobial susceptibility patterns of clinical isolates of M. fortuitum and M. abscessus in Korea, and evaluated the efficacy of a modified broth microdilution method using 2,3-diphenyl-5-thienyl-(2)-tetrazolium chloride (STC), in terms of its ability to provide accurate and easy-to-read minimal inhibitory concentration (MIC) endpoints for the susceptibility testing of rapidly growing mycobacteria. Most isolates of M. fortuitum and M. abscessus in Korea are susceptible or intermediately susceptible to amikacin, cefoxitin, ciprofloxacin, and clarithromycin. Many isolates of M. fortuitum are susceptible to doxycycline, sulfamethoxazole, and imipenem, while many M. abscessus isolates are resistant to these drugs. In the present study, the modified broth microdilution method using STC was found to be reliable, easy to read, and inexpensive for M. fortuitum and M. abscessus susceptibility testing. The modified colorimetric MIC testing method using STC was proven to be a useful surrogate for RGM antibiotic susceptibility testing. PMID:17982223

  4. A single-image method for x-ray refractive index CT

    NASA Astrophysics Data System (ADS)

    Mittone, A.; Gasilov, S.; Brun, E.; Bravin, A.; Coan, P.

    2015-05-01

    X-ray refraction-based computer tomography imaging is a well-established method for nondestructive investigations of various objects. In order to perform the 3D reconstruction of the index of refraction, two or more raw computed tomography phase-contrast images are usually acquired and combined to retrieve the refraction map (i.e. differential phase) signal within the sample. We suggest an approximate method to extract the refraction signal, which uses a single raw phase-contrast image. This method, here applied to analyzer-based phase-contrast imaging, is employed to retrieve the index of refraction map of a biological sample. The achieved accuracy in distinguishing the different tissues is comparable with the non-approximated approach. The suggested procedure can be used for precise refraction computer tomography with the advantage of a reduction of at least a factor of two of both the acquisition time and the dose delivered to the sample with respect to any of the other algorithms in the literature.

  5. Analysis of graded-index optical fibers by the spectral parameter power series method

    NASA Astrophysics Data System (ADS)

    Castillo-Pérez, Raúl; Kravchenko, Vladislav V.; Torba, Sergii M.

    2015-02-01

    The spectral parameter power series (SPPS) method is a recently introduced technique (Kravchenko 2008 Complex Var. Elliptic Equ. 53 775-89, Kravchenko and Porter 2010 Math. Methods Appl. Sci. 33 459-68) for solving linear differential equations and related spectral problems. In this work we develop an approach based on the SPPS for analysis of graded-index optical fibers. The characteristic equation of the eigenvalue problem for calculation of guided modes is obtained in an analytical form in terms of SPPS. Truncation of the series and consideration in this way of the approximate characteristic equation gives us a simple and efficient numerical method for solving the problem. Comparison with the results obtained by other available techniques reveals clear advantages for the SPPS approach, in particular, with regards to accuracy. Based on the solution of the eigenvalue problem, parameters describing the dispersion are analyzed as well.

  6. Spatial interpolation of precipitation indexes in Sierra Nevada (Spain): comparing the performance of some interpolation methods

    NASA Astrophysics Data System (ADS)

    Pereira, Paulo; Oliva, Marc; Misiune, Ieva

    2015-08-01

    The objective of this paper is to examine the spatial distribution of several precipitation indexes in Sierra Nevada, Spain: mean annual number of wet days (R ≥ 1 mm), mean annual number of heavy rainy days (R ≥ 10 mm) and mean annual number of very heavy precipitation days (R ≥ 20 mm) and test the performance of several interpolation methods using these variables. In total, 17 univariate and multivariate methods were tested. A set of 36 metereological stations distributed in Sierra Nevada and neighbouring areas was analysed in this study. The original data did not followed the normal distribution; thus, a logarithm was applied to data meet normality purposes. Interpolator's performance was assessed using the root mean square error generated from cross-validation. The results showed that the mean annual R ≥ 10 mm and R ≥ 20 mm have a higher variability than R ≥ 1 mm. While the elevation and longitude did not show a significant correlation with the studied indexes, the latitude (i.e. distance to the sea) showed a significant negative correlation. The regressions carried out confirmed that elevation was the covariate with higher capacity to explain the variability of the indexes. The incorporation of elevation and longitude slightly increased the explanation capacity of the models. The data of LogR ≥ 1 mm, LogR ≥ 10 mm and LogR ≥ 20 mm displayed a clustered pattern, especially the last two indexes that also showed a strong spatial dependency attributed to the effects of local topography, slope, aspect and valley orientation. The best fitted variogram model to LogR ≥ 1 mm was the linear one while for the LogR ≥ 10 mm and LogR ≥ 20 mm, the Gaussian was the most appropriate. The best interpolator for LogR ≥ 1 mm was the local polinomyal with the power of 1, whereas for LogR ≥ 10 mm and LogR ≥ 20 mm, regression kriging (ROK) using as auxiliary variables the elevation, latitude and longitude was the most accurate. ROK methods significantly

  7. Methods Used to Assess the Susceptibility to Contamination of Transient, Non-Community Public Ground-Water Supplies in Indiana

    USGS Publications Warehouse

    Arihood, Leslie D.; Cohen, David A.

    2006-01-01

    The Safe Water Drinking Act of 1974 as amended in 1996 gave each State the responsibility of developing a Source-Water Assessment Plan (SWAP) that is designed to protect public-water supplies from contamination. Each SWAP must include three elements: (1) a delineation of the source-water protection area, (2) an inventory of potential sources of contaminants within the area, and (3) a determination of the susceptibility of the public-water supply to contamination from the inventoried sources. The Indiana Department of Environmental Management (IDEM) was responsible for preparing a SWAP for all public-water supplies in Indiana, including about 2,400 small public ground-water supplies that are designated transient, non-community (TNC) supplies. In cooperation with IDEM, the U.S. Geological Survey compiled information on conditions near the TNC supplies and helped IDEM complete source-water assessments for each TNC supply. The delineation of a source-water protection area (called the assessment area) for each TNC ground-water supply was defined by IDEM as a circular area enclosed by a 300-foot radius centered at the TNC supply well. Contaminants of concern (COCs) were defined by IDEM as any of the 90 contaminants for which the U.S. Environmental Protection Agency has established primary drinking-water standards. Two of these, nitrate as nitrogen and total coliform bacteria, are Indiana State-regulated contaminants for TNC water supplies. IDEM representatives identified potential point and nonpoint sources of COCs within the assessment area, and computer database retrievals were used to identify potential point sources of COCs in the area outside the assessment area. Two types of methods-subjective and subjective hybrid-were used in the SWAP to determine susceptibility to contamination. Subjective methods involve decisions based upon professional judgment, prior experience, and (or) the application of a fundamental understanding of processes without the collection and

  8. Determination of Isavuconazole Susceptibility of Aspergillus and Candida Species by the EUCAST Method

    PubMed Central

    Howard, Susan J.; Lass-Flörl, Cornelia; Cuenca-Estrella, Manuel; Gomez-Lopez, Alicia

    2013-01-01

    Isavuconazole is a novel expanded-spectrum triazole, which has recently been approved by the FDA as an orphan drug to treat invasive aspergillosis and is currently being studied in phase III clinical trials for invasive candidiasis. The susceptibility of relatively few clinical isolates has been reported. In this study, the isavuconazole susceptibilities of 1,237 Aspergillus and 2,010 Candida geographically diverse clinical isolates were determined by EUCAST methodology at four European mycology laboratories, producing the largest multicenter data set thus far for this compound. In addition, a blinded collection of 30 cyp51A mutant Aspergillus fumigatus clinical isolates and 10 wild-type isolates was tested. From these two data sets, the following preliminary epidemiological cutoff (ECOFF) values were suggested: 2 mg/liter for Aspergillus fumigatus, Aspergillus terreus, and Aspergillus flavus; 4 mg/liter for Aspergillus niger; 0.25 mg/liter for Aspergillus nidulans; and 0.03 mg/liter for Candida albicans, Candida parapsilosis, and Candida tropicalis. Unfortunately, ECOFFs could not be determined for Candida glabrata or Candida krusei due to an unexplained interlaboratory MIC variation. For the blinded collection of A. fumigatus isolates, all MICs were ≤2 mg/liter for wild-type isolates. Differential isavuconazole MICs were observed for triazole-resistant A. fumigatus isolates with different cyp51A alterations: TR34/L98H mutants had elevated isavuconazole MICs, whereas isolates with G54 and M220 alterations had MICs in the wild-type range, suggesting that the efficacy of isavuconazole may not be affected by these alterations. This study will be an aid in interpreting isavuconazole MICs for clinical care and an important step in the future process of setting official clinical breakpoints. PMID:23959309

  9. Sensitivity analysis of TOPSIS method in water quality assessment II: sensitivity to the index input data.

    PubMed

    Li, Peiyue; Wu, Jianhua; Qian, Hui; Chen, Jie

    2013-03-01

    This is the second part of the study on sensitivity analysis of the technique for order preference by similarity to ideal solution (TOPSIS) method in water quality assessment. In the present study, the sensitivity of the TOPSIS method to the index input data was investigated. The sensitivity was first theoretically analyzed under two major assumptions. One assumption was that one index or more of the samples were perturbed with the same ratio while other indices kept unchanged. The other one was that all indices of a given sample were changed simultaneously with the same ratio, while the indices of other samples were unchanged. Furthermore, a case study under assumption 2 was also carried out in this paper. When the same indices of different water samples are changed simultaneously with the same variation ratio, the final water quality assessment results will not be influenced at all. When the input data of all indices of a given sample are perturbed with the same variation ratio, the assessment values of all samples will be influenced theoretically. However, the case study shows that only the perturbed sample is sensitive to the variation, and a simple linear equation representing the relation between the closeness coefficient (CC) values of the perturbed sample and variation ratios can be derived under the assumption 2. This linear equation can be used for determining the sample orders under various variation ratios. PMID:22832843

  10. Method of time resolved refractive index measurements of x-ray laser heated solids

    SciTech Connect

    Williams, G. O.; Kuenzel, S.; Fajardo, M.; Vinko, S. M.; Sardinha, A. B.; Zeitoun, Ph.

    2013-04-15

    With the advent of new x-ray light-sources worldwide, the creation of dense, uniformly heated plasma states arising from intense x-ray irradiation of solids has been made possible. In the early stages of x-ray solid heating, before significant hydrodynamic motion occurs, the matter exists in a highly non-equilibrium state. A method based on wavefront sensing is proposed to probe some of the fundamental properties of these states. The deflection and absorption of a high harmonic probe beam propagated through the plasma can be measured with a wavefront sensor, and allow for the determination of the complex refractive index (RI) of the plasma, giving a 2D map of the optical properties as function of time in a pump-probe arrangement. A solid heating model has been used to estimate the expected temperatures of x-ray heated thin foils, and these temperatures are used in three separate models to estimate the changes in the refractive index. The calculations show the changes induced on an extreme ultra-violet (XUV) probe beam by a solid density thin foil plasma are significant, in terms of deflection angle and absorption, to be measured by already existing XUV Hartmann wavefront sensors. The method is applicable to a wide range of photon energies in the XUV (10 s to several 100 s of eV) and plasma parameters, and can add much needed experimental data to the fundamental properties of such dense plasma states.

  11. Multicenter Comparison of the Etest and EUCAST Methods for Antifungal Susceptibility Testing of Candida Isolates to Micafungin.

    PubMed

    Bougnoux, M-E; Dannaoui, E; Accoceberry, I; Angoulvant, A; Bailly, E; Botterel, F; Chevrier, S; Chouaki, T; Cornet, M; Dalle, F; Datry, A; Dupuis, A; Fekkar, A; Gangneux, J P; Guitard, J; Hennequin, C; Le Govic, Y; Le Pape, P; Maubon, D; Ranque, S; Sautour, M; Sendid, B; Chandenier, J

    2016-08-01

    In vitro susceptibility of 933 Candida isolates, from 16 French hospitals, to micafungin was determined using the Etest in each center. All isolates were then sent to a single center for determination of MICs by the EUCAST reference method. Overall essential agreement between the two tests was 98.5% at ±2 log2 dilutions and 90.2% at ±1 log2 dilutions. Categorical agreement was 98.2%. The Etest is a valuable alternative to EUCAST for the routine determination of micafungin MICs in medical mycology laboratories. PMID:27297480

  12. Performance index and meta-optimization of a direct search optimization method

    NASA Astrophysics Data System (ADS)

    Krus, P.; Ölvander, J.

    2013-10-01

    Design optimization is becoming an increasingly important tool for design, often using simulation as part of the evaluation of the objective function. A measure of the efficiency of an optimization algorithm is of great importance when comparing methods. The main contribution of this article is the introduction of a singular performance criterion, the entropy rate index based on Shannon's information theory, taking both reliability and rate of convergence into account. It can also be used to characterize the difficulty of different optimization problems. Such a performance criterion can also be used for optimization of the optimization algorithms itself. In this article the Complex-RF optimization method is described and its performance evaluated and optimized using the established performance criterion. Finally, in order to be able to predict the resources needed for optimization an objective function temperament factor is defined that indicates the degree of difficulty of the objective function.

  13. Comparing Methods for Identifying Biologically Implausible Values in Height, Weight, and Body Mass Index Among Youth.

    PubMed

    Lawman, Hannah G; Ogden, Cynthia L; Hassink, Sandra; Mallya, Giridhar; Vander Veur, Stephanie; Foster, Gary D

    2015-08-15

    As more epidemiologic data on childhood obesity become available, researchers are faced with decisions regarding how to determine biologically implausible values (BIVs) in height, weight, and body mass index. The purpose of the current study was 1) to track how often large, epidemiologic studies address BIVs, 2) to review BIV identification methods, and 3) to apply those methods to a large data set of youth to determine the effects on obesity and BIV prevalence estimates. Studies with large samples of anthropometric data (n > 1,000) were reviewed to track whether and how BIVs were defined. Identified methods were then applied to a longitudinal sample of 13,662 students (65% African American, 52% male) in 55 urban, low-income schools that enroll students from kindergarten through eighth grade (ages 5-13 years) in Philadelphia, Pennsylvania, during 2011-2012. Using measured weight and height at baseline and 1-year follow-up, we compared descriptive statistics, weight status prevalence, and BIV prevalence estimates. Eleven different BIV methods were identified. When these methods were applied to a large data set, severe obesity and BIV prevalence ranged from 7.2% to 8.6% and from 0.04% to 1.68%, respectively. Approximately 41% of large epidemiologic studies did not address BIV identification, and existing identification methods varied considerably. Increased standardization of the identification and treatment of BIVs may aid in the comparability of study results and accurate monitoring of obesity trends. PMID:26182944

  14. Comparing Methods for Identifying Biologically Implausible Values in Height, Weight, and Body Mass Index Among Youth

    PubMed Central

    Lawman, Hannah G.; Ogden, Cynthia L.; Hassink, Sandra; Mallya, Giridhar; Vander Veur, Stephanie; Foster, Gary D.

    2015-01-01

    As more epidemiologic data on childhood obesity become available, researchers are faced with decisions regarding how to determine biologically implausible values (BIVs) in height, weight, and body mass index. The purpose of the current study was 1) to track how often large, epidemiologic studies address BIVs, 2) to review BIV identification methods, and 3) to apply those methods to a large data set of youth to determine the effects on obesity and BIV prevalence estimates. Studies with large samples of anthropometric data (n > 1,000) were reviewed to track whether and how BIVs were defined. Identified methods were then applied to a longitudinal sample of 13,662 students (65% African American, 52% male) in 55 urban, low-income schools that enroll students from kindergarten through eighth grade (ages 5–13 years) in Philadelphia, Pennsylvania, during 2011–2012. Using measured weight and height at baseline and 1-year follow-up, we compared descriptive statistics, weight status prevalence, and BIV prevalence estimates. Eleven different BIV methods were identified. When these methods were applied to a large data set, severe obesity and BIV prevalence ranged from 7.2% to 8.6% and from 0.04% to 1.68%, respectively. Approximately 41% of large epidemiologic studies did not address BIV identification, and existing identification methods varied considerably. Increased standardization of the identification and treatment of BIVs may aid in the comparability of study results and accurate monitoring of obesity trends. PMID:26182944

  15. A theoretical drought classification method for the multivariate drought index based on distribution properties of standardized drought indices

    NASA Astrophysics Data System (ADS)

    Hao, Zengchao; Hao, Fanghua; Singh, Vijay P.; Xia, Youlong; Ouyang, Wei; Shen, Xinyi

    2016-06-01

    Drought indices have been commonly used to characterize different properties of drought and the need to combine multiple drought indices for accurate drought monitoring has been well recognized. Based on linear combinations of multiple drought indices, a variety of multivariate drought indices have recently been developed for comprehensive drought monitoring to integrate drought information from various sources. For operational drought management, it is generally required to determine thresholds of drought severity for drought classification to trigger a mitigation response during a drought event to aid stakeholders and policy makers in decision making. Though the classification of drought categories based on the univariate drought indices has been well studied, drought classification method for the multivariate drought index has been less explored mainly due to the lack of information about its distribution property. In this study, a theoretical drought classification method is proposed for the multivariate drought index, based on a linear combination of multiple indices. Based on the distribution property of the standardized drought index, a theoretical distribution of the linear combined index (LDI) is derived, which can be used for classifying drought with the percentile approach. Application of the proposed method for drought classification of LDI, based on standardized precipitation index (SPI), standardized soil moisture index (SSI), and standardized runoff index (SRI) is illustrated with climate division data from California, United States. Results from comparison with the empirical methods show a satisfactory performance of the proposed method for drought classification.

  16. In Vitro Amphotericin B Susceptibility of Malassezia pachydermatis Determined by the CLSI Broth Microdilution Method and Etest Using Lipid-Enriched Media

    PubMed Central

    Álvarez-Pérez, Sergio; Peláez, Teresa; Cutuli, Maite; García, Marta E.

    2014-01-01

    We determined the in vitro amphotericin B susceptibility of 60 Malassezia pachydermatis isolates by the CLSI broth microdilution method and the Etest using lipid-enriched media. All isolates were susceptible at MICs of ≤1 μg/ml, confirming the high activity of amphotericin B against this yeast species. Overall, the essential agreement between the tested methods was high (80% and 96.7% after 48 h and 72 h, respectively), and all discrepancies were regarded as nonsubstantial. PMID:24752258

  17. Stability-indicating HPLC method for the determination of impurities in meprobamate with refractive index detection.

    PubMed

    Karthikeyan, K; Balaji, T S; Shanmugasundaram, P; Chandrasekara Pillai, K

    2010-03-01

    The purpose of this study is to develop and validate a simple, sensitive, and robust high-performance liquid chromagraphic (HPLC) method for the determination of impurities ca. 2-methyl-2-propyl-1,3-propane diol (MP0) and 2-hydroxymethyl-2-methyl pentyl carbamate (MP1) in meprobamate (MEP) drug substance with refractive index (RI) detection. This method utilizes a Zorbax Eclipse XDB C(18) HPLC column, a mobile phase of 80:20 (v/v) 10 mM KH(2)PO(4),-acetonitrile, respectively. The stability-indicating capability of the method has been established by performing stress studies under acidic, basic, oxidation, light, humidity, and thermal conditions. The major degradation products of acid and base hydrolysis are identified as MP0 and MP1. The recovery data obtained for impurities are between 96.0-109.8%. The detection and quantitation limits of this method ranges from 0.009 to 0.017 mg/mL and 0.029 to 0.055 mg/mL, respectively. The relative standard deviation (RSD) for the area at QL is less than 6.1%. Good linearity (r(2) > 0.99) and precision (RSD < 2.2%) have been obtained for MEP, MP0, and MP1. This method has been applied successfully to determine the content of impurities in MEP bulk drug. PMID:20223088

  18. Improved Broth Microdilution Method for Antimicrobial Susceptibility Testing of Francisella Noatunensis Orientalis.

    PubMed

    Soto, Esteban; Halliday-Simmonds, Iona; Francis, Stewart; Fraites, Trellor; Martínez-López, Beatriz; Wiles, Judy; Hawke, John P; Endris, Richard D

    2016-09-01

    In this project we optimized a minimal inhibitory concentration testing protocol for Francisella noatunensis orientalis. Thirty-three F. noatunensis orientalis isolates recovered from different fish species and locations were tested, and Escherichia coli ATCC 25922 was used as a quality control reference strain. A modified cation-adjusted Mueller Hinton broth supplemented with 2% IsoVitalex and 0.1% glucose (MMH) was tested at a pH of 6.4 ± 0.1, 7.1 ± 0.1, and 7.3 ± 0.1. Growth curves generated for F. noatunensis orientalis indicated that MMH at a pH of 6.4 ± 0.1 provided optimal growth. There were no significant differences in the growth curves obtained from isolates recovered from different fish species or from fresh or marine water. The pH of 6.4 ± 0.1 in the MMH media interfered with the inhibitory properties of the potentiated sulfonamides (ormetoprim-sulfadimethoxine and trimethoprim-sulfamethoxazole) when using the E. coli ATCC reference strain. Minimal inhibitory concentrations of eight antimicrobials (gentamicin, enrofloxacin, ampicillin, oxytetracycline, erythromycin, florfenicol, flumequine, and oxolinic acid) were similar for all F. noatunensis orientalis isolates. The in vitro susceptibility data provided here can provide a baseline for monitoring the development of antimicrobial resistance among F. noatunensis orientalis isolates, as well as provide valuable data in the development of potential therapeutics. Received October 27, 2015; accepted April 13, 2016. PMID:27484609

  19. Blending and Downscaling of Landsat and MODIS Surface Reflectance for Water Body Delineation: A Comparison of Index-Simulate and Simulate-Index Methods

    NASA Astrophysics Data System (ADS)

    Jarihani, A.; Callow, J. N.; McVicar, T.; Van Niel, T.; Johansen, K.; Emelyanova, I.

    2013-12-01

    Single-sensor satellite remotely sensed data are typically either high temporal and low spatial resolution (e.g. MODIS) or low temporal and high spatial resolution (e.g. Landsat). Blending algorithms have been developed to overcome this limitation by predicting the composition of higher spatial and temporal resolution band data by blending individual corresponding bands of two sensors. The objective of this paper was to evaluate the accuracy of two advanced algorithms (STARFM and ESTARFM) in blending single bands and indices to downscale MODIS pixels (250-500 m) to Landsat resolution (28.5 m). We test two approaches to predicting indices: i) Index-Simulate (IS)-(i.e., indices directly predicted including EVI, NDVI NDWI24 and NDWI 27) from Landsat-MODIS pairs) and ii) Simulate- Index (SI)-(i.e. indices were calculated from five predicted bands (Blue, Green, Red, Near-Infrared and Mid-Infrared). Landsat-like images and indices (IS and SI) were predicted for 18 dates by using 20 pairs of cloud-free Landsat 5 TM and Aqua MODIS images and compared with observed Landsat images and indices. Based on RMSD (accuracy of predicted and observed bands and indices), pixel-to-pixel accuracy of each prediction and R-squared differences of predicted and observed pixels, ESTARFM produced a lower error than STARFM in predicting all four tested indices. Results of IS and SI methods showed that, both algorithms predict indices in IS method with higher accuracy than using SI method. That is, if interested in using indices in applications it best to calculate the index at the two resolutions then use the algorithms to simulate the index as opposed to simulating the individual bands then subsequently calculating the index. This study shows that, the high spatio-temporal resolution predicted water index (NDWI) can be used in water resources applications. Landsat-like daily water indices simulated by using blending Landsat and MODIS data provided daily flood inundation footprint. These

  20. Final report from the Committee on Antimicrobial Susceptibility Testing, Japanese Society of Chemotherapy, on the agar dilution method (2007).

    PubMed

    Nagayama, Ariaki; Yamaguchi, Keizo; Watanabe, Kunitomo; Tanaka, Masatoshi; Kobayashi, Intetsu; Nagasawa, Zenzo

    2008-10-01

    In 1968, the agar dilution method was developed as an independent Japanese method for measuring the minimal inhibitory concentration (MIC) of antimicrobial agents. As this method differed in a few respects from the MIC measurement methods used in other countries, it was revised in 1981, by a committee headed by Susumu Mitsuhashi, and the revised method (Chemotherapy 29:76-79, 1981) has been used since then. In 1979, an agar dilution method for measuring the MIC of anaerobes was developed by a committee chaired by Nozomu Kosakai (Chemotherapy 27:559-561, 1979). In 1990, a committee headed by Sachiko Goto approved a broth microdilution method for nonfastidious bacteria (Chemotherapy 38:102-105, 1990). Later, a committee headed by Atsushi Saito examined media that would be suitable for nonfastidious bacteria and fastidious bacteria, and they endeavored to prepare a broth microdilution method for anaerobic bacteria. In this context, a new broth microdilution method was proposed at the 40th Annual Meeting of the Japanese Society of Chemotherapy (JSC) in Nagoya in 1992, and the proposal was adopted as the standard JSC method after some modification (Chemotherapy 41: 183-189, 1993). The agar dilution method has remained unrevised for approximately 20 years. A proposal to review this method was recently made, and the 2007 Committee on Antimicrobial Susceptibility Testing was formed, comprising the JSC members listed below. Under the auspices of this committee, the method revised in 1981 was reviewed in comparison to the international standard method (Clinical and Laboratory Standards Institute [CLSI] method). PMID:18936894

  1. Multireservoir real-time operations for flood control using balanced water level index method.

    PubMed

    Wei, Chih-Chiang; Hsu, Nien-Sheng

    2008-09-01

    This paper presents a real-time simulation-optimization operation procedure for determining the reservoir releases at each time step during a flood. The proposed procedure involves two models, i.e., a hydrological forecasting model and a reservoir operation model. In the reservoir operation model, this paper compares two flood-control operation strategies for a multipurpose multireservoir system. While Strategy 1 is the real-time joint reservoir operations without using the balanced water level index (BWLI) method, Strategy 2 involves real-time joint reservoir operations using the BWLI method. The two strategies presented are formulated as mixed-integer linear programming (MILP) problems. The idea of using the BWLI method is derived from the HEC-5 program developed by the US Army Corps of Engineers. The proposed procedure has been applied to the Tanshui River Basin system in Taiwan using the 6h ahead forecast data of six typhoons. A comparison of the results obtained from the two strategies reveals that Strategy 2 performs much better than Strategy 1 in determining the reservoir real-time releases throughout the system during flood emergencies in order to minimize flooding, while maintaining all reservoirs in the system in balance if possible. Consequently, the proposed model using the BWLI method demonstrates its effectiveness in estimating real-time releases. PMID:17923249

  2. Nanocrystalline glass-ceramics implementation methods and refractive index modelling thereof

    NASA Astrophysics Data System (ADS)

    Vinogradova, Irina L.; Sultanov, Albert K.; Meshkov, Ivan K.; Andrianova, Anna V.; Salikhov, Aidar I.; Abdrakhmanova, Guzel I.; Yantilina, Liliya Z.

    2016-03-01

    Clear nanocrystalline material receipt possibilities are described in the paper. We investigated the possibility to process the glass-ceramics and quartz by intense torsion under high pressure. We found that due to the lack of plasticity of the material zone to maintain the integrity of the sample it is necessary to apply heating up to 200-250°C. The resulting material is supposed to be used in fiber-optic telecommunication systems. We conducted mathematical modeling of the refractive index in the linear and nonlinear mode capacities for nanostructured glass-ceramics. The analytical method is based on the strain oscillator motion under outer light wave effect model. We also found the coefficient of nonlinear stiffness for nanostructured glass-ceramics.

  3. RATIONAL DETERMINATION METHOD OF PROBABLE FREEZING INDEX FOR n-YEARS CONSIDERING THE REGIONAL CHARACTERISTICS

    NASA Astrophysics Data System (ADS)

    Kawabata, Shinichiro; Hayashi, Keiji; Kameyama, Shuichi

    This paper investigates a method for ob taining the probable freezing index for n -years from past frostaction damage and meteorological data. From investigati on of Japanese cold winter data from the areas of Hokkaido, Tohoku and south of Tohoku, it was found that the extent of cold winter had regularity by location south or north. Also, after obtaining return periods of cold winters by area, obvious regional characteristics were found. Mild winters are rare in Hokkaido. However, it was clarified that when Hokkaido had cold winters, its size increased. It wa s effective to determine the probable freezing indices as 20-, 15- and 10-year return periods for Hokkaido, Tohoku and south of Tohoku, respectively.

  4. EEG quantification of alertness: methods for early identification of individuals most susceptible to sleep deprivation

    NASA Astrophysics Data System (ADS)

    Berka, Chris; Levendowski, Daniel J.; Westbrook, Philip; Davis, Gene; Lumicao, Michelle N.; Olmstead, Richard E.; Popovic, Miodrag; Zivkovic, Vladimir T.; Ramsey, Caitlin K.

    2005-05-01

    Electroencephalographic (EEG) and neurocognitive measures were simultaneously acquired to quantify alertness from 24 participants during 44-hours of sleep deprivation. Performance on a three-choice vigilance task (3C-VT), paired-associate learning/memory task (PAL) and modified Maintenance of Wakefulness Test (MWT), and sleep technician-observed drowsiness (eye-closures, head-nods, EEG slowing) were quantified. The B-Alert system automatically classifies each second of EEG on an alertness/drowsiness continuum. B-Alert classifications were significantly correlated with technician-observations, visually scored EEG and performance measures. B-Alert classifications during 3C-VT, and technician observations and performance during the 3C-VT and PAL evidenced progressively increasing drowsiness as a result of sleep deprivation with a stabilizing effect observed at the batteries occurring between 0600 and 1100 suggesting a possible circadian effect similar to those reported in previous sleep deprivation studies. Participants were given an opportunity to take a 40-minute nap approximately 24-hours into the sleep deprivation portion of the study (i.e., 7 PM on Saturday). The nap was followed by a transient period of increased alertness. Approximately 8 hours after the nap, behavioral and physiological measures of drowsiness returned to levels prior to the nap. Cluster analysis was used to stratify individuals into three groups based on their level of impairment as a result of sleep deprivation. The combination of B-Alert and neuro-behavioral measures may identify individuals whose performance is most susceptible to sleep deprivation. These objective measures could be applied in an operational setting to provide a "biobehavioral assay" to determine vulnerability to sleep deprivation.

  5. Toward Reliable Estimates of Abundance: Comparing Index Methods to Assess the Abundance of a Mammalian Predator

    PubMed Central

    Güthlin, Denise; Storch, Ilse; Küchenhoff, Helmut

    2014-01-01

    Due to time and financial constraints indices are often used to obtain landscape-scale estimates of relative species abundance. Using two different field methods and comparing the results can help to detect possible bias or a non monotonic relationship between the index and the true abundance, providing more reliable results. We used data obtained from camera traps and feces counts to independently estimate relative abundance of red foxes in the Black Forest, a forested landscape in southern Germany. Applying negative binomial regression models, we identified landscape parameters that influence red fox abundance, which we then used to predict relative red fox abundance. We compared the estimated regression coefficients of the landscape parameters and the predicted abundance of the two methods. Further, we compared the costs and the precision of the two field methods. The predicted relative abundances were similar between the two methods, suggesting that the two indices were closely related to the true abundance of red foxes. For both methods, landscape diversity and edge density best described differences in the indices and had positive estimated effects on the relative fox abundance. In our study the costs of each method were of similar magnitude, but the sample size obtained from the feces counts (262 transects) was larger than the camera trap sample size (88 camera locations). The precision of the camera traps was lower than the precision of the feces counts. The approach we applied can be used as a framework to compare and combine the results of two or more different field methods to estimate abundance and by this enhance the reliability of the result. PMID:24743565

  6. Method for the simultaneous determination of total polyphenol and anthocyan indexes in red wines using a flow injection approach.

    PubMed

    González-Rodríguez, J; Pérez-Juan, P; Luque de Castro, M D

    2002-01-01

    A simultaneous and fast method for the determination of total polyphenol index (t.p.i.) and total anthocyan index (t.a.i.) has been developed by a flow injection approach and a diode array spectrophotometer for monitoring at 280 and 520 nm, respectively. Linear ranges were obtained from 20 to 70 index units and from 20 to 500 mg l(-1) for the t.p.i. and t.a.i., respectively. The results provided by the proposed method agree with those obtained using the polyphenol index at 280 nm and the Ribereau-Gayon method for the determination of total anthocyans. The sample throughout was 25-30 samples per hour. Analytical features such as repeatability, reproducibility and detection and quantification limits as well as the results of a robustness study based on the Steiner-Younden procedure are also given. PMID:18968479

  7. Method for indexing and retrieving manufacturing-specific digital imagery based on image content

    DOEpatents

    Ferrell, Regina K.; Karnowski, Thomas P.; Tobin, Jr., Kenneth W.

    2004-06-15

    A method for indexing and retrieving manufacturing-specific digital images based on image content comprises three steps. First, at least one feature vector can be extracted from a manufacturing-specific digital image stored in an image database. In particular, each extracted feature vector corresponds to a particular characteristic of the manufacturing-specific digital image, for instance, a digital image modality and overall characteristic, a substrate/background characteristic, and an anomaly/defect characteristic. Notably, the extracting step includes generating a defect mask using a detection process. Second, using an unsupervised clustering method, each extracted feature vector can be indexed in a hierarchical search tree. Third, a manufacturing-specific digital image associated with a feature vector stored in the hierarchicial search tree can be retrieved, wherein the manufacturing-specific digital image has image content comparably related to the image content of the query image. More particularly, can include two data reductions, the first performed based upon a query vector extracted from a query image. Subsequently, a user can select relevant images resulting from the first data reduction. From the selection, a prototype vector can be calculated, from which a second-level data reduction can be performed. The second-level data reduction can result in a subset of feature vectors comparable to the prototype vector, and further comparable to the query vector. An additional fourth step can include managing the hierarchical search tree by substituting a vector average for several redundant feature vectors encapsulated by nodes in the hierarchical search tree.

  8. A New Evaluation Method for Groundwater Quality Applied in Guangzhou Region, China: Using Fuzzy Method Combining Toxicity Index.

    PubMed

    Liu, Fan; Huang, Guanxing; Sun, Jichao; Jing, Jihong; Zhang, Ying

    2016-02-01

    Groundwater quality assessment is essential for drinking from a security point of view. In this paper, a new evaluation method called toxicity combined fuzzy evaluation (TCFE) has been put forward, which is based on the fuzzy synthetic evaluation (FSE) method and the toxicity data from Agency for Toxic Substances and Disease Registry. The comparison of TCFE and FSE in the groundwater quality assessment of Guangzhou region also has been done. The assessment results are divided into 5 water quality levels; level I is the best while level V is the worst. Results indicate that the proportion of level I, level II, and level III used by the FSE method was 69.33% in total. By contrast, this proportion rose to 81.33% after applying the TCFE method. In addition, 66.7% of level IV samples in the FSE method became level I (50%), level II (25%), and level III (25%) in the TCFE method and 29.41% of level V samples became level I (50%) and level III (50%). This trend was caused by the weight change after the combination of toxicity index. By analyzing the changes of different indicators' weight, it could be concluded that the better-changed samples mainly exceeded the corresponding standards of regular indicators and the deteriorated samples mainly exceeded the corresponding standards of toxic indicators. The comparison between the two results revealed that the TCFE method could represent the health implications of toxic indicators reasonably. As a result, the TCFE method is more scientific in view of drinking safety. PMID:26803098

  9. Comparative evaluation of tigecycline susceptibility testing methods for expanded-spectrum cephalosporin- and carbapenem-resistant gram-negative pathogens.

    PubMed

    Zarkotou, Olympia; Pournaras, Spyros; Altouvas, George; Pitiriga, Vassiliki; Tziraki, Maria; Mamali, Vassiliki; Themeli-Digalaki, Katerina; Tsakris, Athanassios

    2012-11-01

    We evaluated the Vitek2, Etest, and MIC Test Strip (MTS) methods of tigecycline susceptibility testing with 241 expanded-spectrum cephalosporin-resistant and/or carbapenem-resistant Enterobacteriaceae and Acinetobacter baumannii clinical isolates by using dry-form broth microdilution (BMD) as the reference method. The MIC(50/90)s were as follows: BMD, 1/4 μg/ml; Vitek2, 4/≥8 μg/ml; Etest, 2/4 μg/ml; MTS, 0.5/2 μg/ml. Vitek2 produced 9.1/21.2% major errors, Etest produced 0.4/0.8% major errors, and MTS produced no major errors but 0.4/3.3% very major errors (FDA/EUCAST breakpoints). Vitek2 tigecycline results require confirmation by BMD or Etest for multidrug-resistant pathogens. PMID:22933593

  10. Importance of biofilm in Candida parapsilosis and evaluation of its susceptibility to antifungal agents by colorimetric method.

    PubMed

    Růzicka, F; Holá, V; Votava, M; Tejkalová, R

    2007-01-01

    The ability of C. parapsilosis (an important cause of nosocomial infections) to produce biofilm was evaluated in 32 bloodstream isolates and 85 strains isolated from skin. The biofilm formation was found in 19 (59%) blood isolates and only in 33 (39%) isolates from skin. The antifungal susceptibility was assessed for amphotericin B, itraconazole and voriconazole in planktonic and biofilm form of the 19 biofilm-positive bloodstream strains by broth microdilution method according to NCCLS standards. The method was modified by the use of resazurin as a colorimetric indicator of the metabolically active cells which makes the determination of the effect of antifungal agents easier. Biofilm forms of all strains were more resistant than their planktonic form. PMID:17702457

  11. Evaluation of Microcracks orientation at Stromboli volcano using a Magnetic Ferrofluid and the Method of Anisotropy of Magnetic Susceptibility

    NASA Astrophysics Data System (ADS)

    Lewis, O.; Benson, P. M.; Vinciguerra, S.; Meredith, P. G.

    2005-12-01

    Most crustal rocks are anisotropic. In volcanic areas, anisotropy primarily results due to preferred directions of microcracks as magma cools. This effect is, in turn, enhanced due to local stress fields during deposition. The combined effects of these processes may thus give rise to a complex anisotropic fabric. Such fabrics can play crucial roles when enhancing the formation of slip surfaces which can lead to sector collapses of volcanic edifices, as is the case of Stromboli volcano (Italy) which experienced 4 sector collapses in the past 13ka. However, the rapid analysis of anisotropic microcrack fabrics (in terms of magnitude and principal direction) remains non-trivial. Current methods range from time consuming microcrack analysis of thin sections to the preparation of oriented cores for elastic-wave velocity measurement. To further our understanding of how microcrack fabrics influence the bulk properties of volcanic basalt, we employ a novel method which rapidly evaluates the 3-D microcrack orientation using technique of Anisotropy of Magnetic Susceptibility (AMS). First, we determine the rock matrix AMS (mAMS) using standard methods (via a Agico KLY-4 Kappabridge). Samples are then saturated with a magnetic ferrofluid, filling the microcrack network with a magnetically susceptible suspension of microscopic (10nm) magnetite particles. The AMS is then re-measured, with the matrix susceptibility values subtracted from these readings to yield the average 3-D pore space shape, size and orientation (pAMS). We describe the use of this method using basalt from Stromboli and comparing to a granite (Takidani) from the Japanese Alps in order to verify the technique and to investigate the relationship between the basalt microcrack geometry and field scale observation. For Takidani granite we find the structural anisotropy formed by the void space, as measured by pAMS, is well described by elastic wave velocity measurement; exhibiting anisotropy values of 19.1% and 7

  12. Comparative evaluation of three antifungal susceptibility test methods for Candida albicans isolates and correlation with response to fluconazole therapy.

    PubMed Central

    Ruhnke, M; Schmidt-Westhausen, A; Engelmann, E; Trautmann, M

    1996-01-01

    In vitro susceptibilities were determined for 56 Candida albicans isolates obtained from the oral cavities of 41 patients with human immunodeficiency virus infection. The agents tested included fluconazole, itraconazole, ketoconazole, flucytosine, and amphotericin B. MICs were determined by the broth microdilution technique following National Committee for Clinical Laboratory Standards document M27-P (M27-P micro), a broth microdilution technique using high-resolution medium (HR micro), and the Etest with solidified yeast-nitrogen base agar. The in vitro findings were correlated with in vivo response to fluconazole therapy for oropharyngeal candidiasis. For all C. albicans isolates from patients with oropharyngeal candidiasis not responding to fluconazole MICs were found to be > or = 6.25 micrograms/ml by the M27-P micro method and > or = 25 micrograms/ml by the HR micro method as well as the Etest. However, for several C. albicans isolates from patients who responded to fluconazole therapy MICs found to be above the suggested breakpoints of resistance. The appropriate rank order of best agreement between the M27-P micro method and HR micro method was amphotericin B > fluconazole > flucytosine > ketoconazole > itraconazole. The appropriate rank order with best agreement between the M27-P micro method and the Etest was flucytosine > amphotericin B > fluconazole > ketoconazole > or = itraconazole. It could be concluded that a good correlation between in vitro resistance and clinical failure was found with all methods. However, the test methods used in this study did not necessarily predict clinical response to therapy with fluconazole. PMID:8940474

  13. EUCAST technical note on isavuconazole breakpoints for Aspergillus, itraconazole breakpoints for Candida and updates for the antifungal susceptibility testing method documents.

    PubMed

    Arendrup, M C; Meletiadis, J; Mouton, J W; Guinea, J; Cuenca-Estrella, M; Lagrou, K; Howard, S J

    2016-06-01

    The Subcommittee on Antifungal Susceptibility Testing (AFST) of the ESCMID European Committee for Antimicrobial Susceptibility Testing (EUCAST) has determined breakpoints for isavuconazole and Aspergillus and for itraconazole and Candida spp., released a new document summarizing existing and new minimum inhibitory concentration ranges for quality control strains and revised the method documents for yeast and mould susceptibility testing. This technical note is based on the EUCAST isavuconazole and itraconazole rationale documents, version 1.0 of the routine and extended internal quality control for antifungal susceptibility testing as recommended by EUCAST, and the E.Def 7.3, E.Def 9.2 and E.Def 9.3 method documents (http://www.eucast.org). PMID:26851656

  14. Commercial scale fabrication method for fabricating a gradient refractive-index rod: Overcoming volume shrinkage and chemical restrictions.

    PubMed

    Cho, Hansol; Son, Young Mok; Kim, Mu Gyeom; Ra, Byoung Joo; Park, Joon-Yong; Lee, Seung Hui; Choi, Jin Sung; Song, Min Young; Park, O Ok; Kim, Youn Cheol; Hwang, Jin Taek

    2006-10-01

    We report a fabrication method for a gradient refractive-index polymeric object from a binary comonomer system, regardless of the monomers' reactivity ratio and the molar volume criteria of gradient refractive-index development. To fabricate a large gradient refractive-index rod consisting of a methyl methacrylate and 2,2,3,3-tetrafluoropropyl methacrylate comonomer pair that has not been used for fabrication of a copolymer gradient refractive-index rod by previous conventional methods because of chemical restrictions in molar volume and reactivity ratio difference, we use the so-called successive UV polymerization in a controlled radial volume in conjunction with an automatic refill reactor. Simultaneously and automatically, the volume shrinkage problem, an inevitable shortcoming for the fabrication of a large polymeric object in a commercial production scale, is overcome and exploited. The theoretical features of the refractive-index profile generation of this method are also compared with those of conventional methods for which the chemical restrictions of monomers are crucial for the shape of a refractive-index profile. PMID:16983409

  15. Study on the application of the Kent index method on the risk assessment of disastrous accidents in subway engineering.

    PubMed

    Lu, Hao; Wang, Mingyang; Yang, Baohuai; Rong, Xiaoli

    2013-01-01

    With the development of subway engineering, according to uncertain factors and serious accidents involved in the construction of subways, implementing risk assessment is necessary and may bring a number of benefits for construction safety. The Kent index method extensively used in pipeline construction is improved to make risk assessment much more practical for the risk assessment of disastrous accidents in subway engineering. In the improved method, the indexes are divided into four categories, namely, basic, design, construction, and consequence indexes. In this study, a risk assessment model containing four kinds of indexes is provided. Three kinds of risk occurrence modes are listed. The probability index model which considers the relativity of the indexes is established according to the risk occurrence modes. The model provides the risk assessment process through the fault tree method and has been applied in the risk assessment of Nanjing subway's river-crossing tunnel construction. Based on the assessment results, the builders were informed of what risks should be noticed and what they should do to avoid the risks. The need for further research is discussed. Overall, this method may provide a tool for the builders, and improve the safety of the construction. PMID:23710136

  16. Comparative analysis of different retrieval methods for mapping grassland leaf area index using airborne imaging spectroscopy

    NASA Astrophysics Data System (ADS)

    Atzberger, Clement; Darvishzadeh, Roshanak; Immitzer, Markus; Schlerf, Martin; Skidmore, Andrew; le Maire, Guerric

    2015-12-01

    Fine scale maps of vegetation biophysical variables are useful status indicators for monitoring and managing national parks and endangered habitats. Here, we assess in a comparative way four different retrieval methods for estimating leaf area index (LAI) in grassland: two radiative transfer model (RTM) inversion methods (one based on look-up-tables (LUT) and one based on predictive equations) and two statistical modelling methods (one partly, the other entirely based on in situ data). For prediction, spectral data were used that had been acquired over Majella National Park in Italy by the airborne hyperspectral HyMap instrument. To assess the performance of the four investigated models, the normalized root mean squared error (nRMSE) and coefficient of determination (R2) between estimates and in situ LAI measurements are reported (n = 41). Using a jackknife approach, we also quantified the accuracy and robustness of empirical models as a function of the size of the available calibration data set. The results of the study demonstrate that the LUT-based RTM inversion yields higher accuracies for LAI estimation (R2 = 0.91, nRMSE = 0.18) as compared to RTM inversions based on predictive equations (R2 = 0.79, nRMSE = 0.38). The two statistical methods yield accuracies similar to the LUT method. However, as expected, the accuracy and robustness of the statistical models decrease when the size of the calibration database is reduced to fewer samples. The results of this study are of interest for the remote sensing community developing improved inversion schemes for spaceborne hyperspectral sensors applicable to different vegetation types. The examples provided in this paper may also serve as illustrations for the drawbacks and advantages of physical and empirical models.

  17. Identification and Determination of Antibiotic Susceptibilities of Brucella Strains Isolated from Patients in Van, Turkey by Conventional and Molecular Methods

    PubMed Central

    Parlak, Mehmet; Güdücüoğlu, Hüseyin; Bayram, Yasemin; Çıkman, Aytekin; Aypak, Cenk; Kılıç, Selçuk; Berktaş, Mustafa

    2013-01-01

    Purpose: Brucellosis is a worldwide zoonotic disease and still constitutes a major public health problem. In this study, we aimed to identify biovars of Brucella strains isolated from clinical specimens taken from brucellosis patients from the Eastern Anatolia region as well determine the susceptibility of these isolates to tigecycline and azithromycin, drugs that may serve as alternatives to the conventional drugs used in the therapy. Materials and methods: Seventy-five Brucella spp. isolates were included in the study. All strains were identified by both conventional and molecular methods. Brucella Multiplex PCR kit (FC-Biotech, Code: 0301, Turkey) and B. melitensis biovar typing PCR kit (FC-Biotech, Code: 0302, Turkey) were used for molecular typing. Antimicrobial susceptibilities of all strains were determined by E-tests. Results: By conventional biotyping, 73 strains were identified as B. melitensis biovar 3 and two strains as B. abortus biovar 3. Molecular typing results were compatible with conventional methods. The MIC50 and MIC90 values of doxycycline were 0.047 and 0.094; tigecycline 0.094 and 0.125; trimethoprim/sulfamethoxazole 0.064 and 0.19; ciprofloxacin 0.19 for both; streptomycin 0.75 and 1; rifampin 1 and 2 and azithromycin 4 and 8. According to the MIC values, doxycycline was found to be the most effective antibiotic, followed by tigecycline, trimethoprim-sulfamethoxazole and ciprofloxacin. Conclusion: Currently recommended antibiotics for the treatment of brucellosis such as doxycycline, rifampin, streptomycin, trimethoprim-sulfamethoxazole and ciprofloxacin were found to be still effective. While our results showed that tigecycline can be used an alternative agent in the treatment of brucellosis, azithromycin has not been confirmed as an appropriate agent for the treatment. PMID:23983603

  18. Rapid method for determination of antimicrobial susceptibilities pattern of urinary bacteria

    NASA Technical Reports Server (NTRS)

    Picciolo, G. L.; Chapelle, E. W.; Barza, M. J.; Weinstein, L.; Tuttle, S. A.; Vellend, H.

    1975-01-01

    Method determines bacterial sensitivity to antimicrobial agents by measuring level of adenosine triphosphate remaining in the bacteria. Light emitted during reaction of sample with a mixture of luciferase and luciferin is measured.

  19. Methods for comparing drug policies--the utility of composite drug harm indexes.

    PubMed

    Ritter, Alison

    2009-11-01

    One of the challenges for drug policy research is being able to compare policy options and outcomes. The development of indexes, such as the UK Drug Harm Index or the UNODC Illicit Drug Index is a way to systematically enable such comparisons. An Index is a single common metric that represents the diverse outcomes or consequences of drug use. An Index may be used for performance monitoring within one country/region over time; to establish societal benefit of drug policies as expressed in social costs saved; to compare countries or regions; or for comparative policy analysis. Clarity of purpose is important in how an Index is used. The consequences or outcomes that can be combined into a single Index include health consequences, crime consequences, public amenity, pain and suffering, labour market outcomes, and drug manufacture and trafficking activity. The choice of outcomes for inclusion is driven by the purpose but also often by practical considerations, such as data availability. The weighting of the consequences is an important consideration in translating the outcomes into a common metric. A monetary unit has a number of advantages: it is a unit that can be measured across diverse impacts; it gives implicit "weighting" of harms; and it is intuitive for policy makers and community. On the other hand, it represents an economic perspective. No one Index will be regarded as suitable and appropriate by every stakeholder and ongoing research effort on Indexes is an important foundational research activity to advance illicit drug policy. PMID:19356915

  20. Comparative study on compact planar waveguide based photonic integrated couplers using simple effective index method

    NASA Astrophysics Data System (ADS)

    Deka, Bidyut; Dutta, Aradhana; Sahu, Partha P.

    2013-11-01

    The miniaturization of photonic components in integrated optic waveguide devices to microscale platform has attracted enormous attention from the researchers and entrepreneurs. In this paper, we present and report a comparative study of photonic integrated planar waveguide based couplers using a mathematical model based on sinusoidal mode simple effective index method (SEIM). The basic photonic integrated components such as directional coupler (DC), two mode interference (TMI) coupler and multimode interference (MMI) coupler have been designed and fabricated using the versatile SiON waveguide technology (SiON as the waveguide core material using silica waveguide). The experimental results have been compared with the SEIM based theoretical results and further verified with the commercially available software tool based on beam propagation method (BPM). With a focus towards device compactness, particular emphasis is placed on device geometry in an endeavour to achieve the same. In this direction, the theoretical and experimental results obtained have been compared with tooth shaped grating assisted geometry for these photonic components. It is found that the grating assisted structures have the beat length ~0.5 times lower than that of the conventional geometry. Further it is seen that the beat length of TMI coupler is smaller compared to the DC and MMI coupler.

  1. Non-invasive method and apparatus for monitoring intracranial pressure and pressure volume index in humans

    NASA Technical Reports Server (NTRS)

    Yost, William T. (Inventor); Cantrell, Jr., John H. (Inventor)

    1997-01-01

    Non-invasive measuring devices responsive to changes in a patient's intracranial pressure (ICP) can be accurately calibrated for monitoring purposes by providing known changes in ICP by non-invasive methods, such as placing the patient on a tilting bed and calculating a change in ICP from the tilt angle and the length of the patient's cerebrospinal column, or by placing a pressurized skull cap on the patient and measuring the inflation pressure. Absolute values for the patient's pressure-volume index (PVI) and the steady state ICP can then be determined by inducing two known changes in the volume of cerebrospinal fluid while recording the corresponding changes in ICP by means of the calibrated measuring device. The two pairs of data for pressure change and volume change are entered into an equation developed from an equation describing the relationship between ICP and cerebrospinal fluid volume. PVI and steady state ICP are then determined by solving the equation. Methods for inducing known changes in cerebrospinal fluid volume are described.

  2. Re-analysis of Alaskan benchmark glacier mass-balance data using the index method

    USGS Publications Warehouse

    Van Beusekom, Ashely E.; O'Nell, Shad R.; March, Rod S.; Sass, Louis C.; Cox, Leif H.

    2010-01-01

    At Gulkana and Wolverine Glaciers, designated the Alaskan benchmark glaciers, we re-analyzed and re-computed the mass balance time series from 1966 to 2009 to accomplish our goal of making more robust time series. Each glacier's data record was analyzed with the same methods. For surface processes, we estimated missing information with an improved degree-day model. Degree-day models predict ablation from the sum of daily mean temperatures and an empirical degree-day factor. We modernized the traditional degree-day model and derived new degree-day factors in an effort to match the balance time series more closely. We estimated missing yearly-site data with a new balance gradient method. These efforts showed that an additional step needed to be taken at Wolverine Glacier to adjust for non-representative index sites. As with the previously calculated mass balances, the re-analyzed balances showed a continuing trend of mass loss. We noted that the time series, and thus our estimate of the cumulative mass loss over the period of record, was very sensitive to the data input, and suggest the need to add data-collection sites and modernize our weather stations.

  3. The effects of different test methods on the just noticeable difference of clarity index for music.

    PubMed

    Vigeant, Michelle C; Celmer, Robert D; Jasinski, Chris M; Ahearn, Meghan J; Schaeffler, Matthew J; Giacomoni, Clothilde B; Wells, Adam P; Ormsbee, Caitlin I

    2015-07-01

    The just noticeable differences (JNDs) of room acoustics metrics are necessary for research and design of performing arts venues. The goal of this work was to evaluate the effects of different testing methods on the measured JND of clarity index for music (C80). An initial study was conducted to verify the findings of other published works that the C80 JND is approximately 1 dB, as currently listed in ISO 3382:2009 (International Organization for Standardization, Switzerland, 2009), however, the results suggested a higher value. In the second study, the effects of using two variations of the method of constant stimuli were examined, where one variation required the subjects to evaluate the pair of signals by listening to each of them in their entirety, while the second approach allowed the participants to switch back and forth in real-time. More consistent results were obtained with the latter variation and the results indicated a C80 JND greater than 1 dB. In the final study, an extensive training period using the first variation was required, based on the second study, and the data were collected using the second variation. The analysis revealed that for the conditions used in this study (concert hall and chamber music hall) that the C80 JND is approximately 3 dB. PMID:26233046

  4. Retrieving Leaf Area Index (LAI) Using Remote Sensing: Theories, Methods and Sensors

    PubMed Central

    Zheng, Guang; Moskal, L. Monika

    2009-01-01

    The ability to accurately and rapidly acquire leaf area index (LAI) is an indispensable component of process-based ecological research facilitating the understanding of gas-vegetation exchange phenomenon at an array of spatial scales from the leaf to the landscape. However, LAI is difficult to directly acquire for large spatial extents due to its time consuming and work intensive nature. Such efforts have been significantly improved by the emergence of optical and active remote sensing techniques. This paper reviews the definitions and theories of LAI measurement with respect to direct and indirect methods. Then, the methodologies for LAI retrieval with regard to the characteristics of a range of remotely sensed datasets are discussed. Remote sensing indirect methods are subdivided into two categories of passive and active remote sensing, which are further categorized as terrestrial, aerial and satellite-born platforms. Due to a wide variety in spatial resolution of remotely sensed data and the requirements of ecological modeling, the scaling issue of LAI is discussed and special consideration is given to extrapolation of measurement to landscape and regional levels. PMID:22574042

  5. Evaluation of shape indexing methods for content-based retrieval of x-ray images

    NASA Astrophysics Data System (ADS)

    Antani, Sameer; Long, L. Rodney; Thoma, George R.; Lee, Dah-Jye

    2003-01-01

    Efficient content-based image retrieval of biomedical images is a challenging problem of growing research interest. Feature representation algorithms used in indexing medical images on the pathology of interest have to address conflicting goals of reducing feature dimensionality while retaining important and often subtle biomedical features. At the Lister Hill National Center for Biomedical Communications, a R&D division of the National Library of Medicine, we are developing a content-based image retrieval system for digitized images of a collection of 17,000 cervical and lumbar x-rays taken as a part of the second National Health and Nutrition Examination Survey (NHANES II). Shape is the only feature that effectively describes various pathologies identified by medical experts as being consistently and reliably found in the image collection. In order to determine if the state of the art in shape representation methods is suitable for this application, we have evaluated representative algorithms selected from the literature. The algorithms were tested on a subset of 250 vertebral shapes. In this paper we present the requirements of an ideal algorithm, define the evaluation criteria, and present the results and our analysis of the evaluation. We observe that while the shape methods perform well on visual inspection of the overall shape boundaries, they fall short in meeting the needs of determining similarity between the vertebral shapes based on the pathology.

  6. Evaluation of agar dilution and broth microdilution methods to determine the disinfectant susceptibility.

    PubMed

    Wu, Guoyan; Yang, Qianru; Long, Mei; Guo, Lijuan; Li, Bei; Meng, Yue; Zhang, Anyun; Wang, Hongning; Liu, Shuliang; Zou, Likou

    2015-11-01

    A variety of disinfectants have been widely used in veterinary hygiene, food industries and environments, which could induce the development of bacterial resistance to disinfectants. The methods used to investigate antimicrobial effects of disinfectant vary considerably among studies, making comparisons difficult. In this study, agar dilution and broth microdilution methods were used to compare the antimicrobial activities of four quaternary ammonium compounds (QACs) against foodborne and zoonotic pathogens. The potential relationship between the presence of QACs resistance genes and phenotypic resistance to QACs was also investigated. Our results indicated that the minimum inhibitory concentrations (MICs) determined by two methods might be different depended upon different QACs and bacteria applied. Regardless of the testing methods, Klebsiella pneumoniae was more tolerant among Gram-negative strains to four QACs, followed by Salmonella and Escherichia coli. The agreement between MICs obtained by the two methods was good, for benzalkonium chloride (78.15%), didecyldimethylammonium chloride (DDAC) (82.35%), cetylpyridinium chloride (CTPC) (97.48%) and cetyltrimethylammonium bromide (CTAB) (99.16%), respectively. Among all Gram-negative bacteria, 94.55% (n=52) of qacEΔ1-positive strains showed higher MICs (512 mg l(-1)) to CTAB. The qacEΔ1 gene was highly associated (P<0.05) with the high MICs of QACs (⩾512 mg l(-1)). In addition, DDAC remained as the most effective disinfectant against both Gram-positive and Gram-negative bacteria. This is the first study that compared the agar dilution and broth microdilution methods to assess the antimicrobial activity of QACs. The study demonstrated the need to standardize method that would be used in evaluating QACs antimicrobial properties in the future. PMID:25944532

  7. COMPARISON BETWEEN AUTOMATED SYSTEM AND PCR-BASED METHOD FOR IDENTIFICATION AND ANTIMICROBIAL SUSCEPTIBILITY PROFILE OF CLINICAL Enterococcus spp

    PubMed Central

    Furlaneto-Maia, Luciana; Rocha, Kátia Real; Siqueira, Vera Lúcia Dias; Furlaneto, Márcia Cristina

    2014-01-01

    Enterococci are increasingly responsible for nosocomial infections worldwide. This study was undertaken to compare the identification and susceptibility profile using an automated MicrosScan system, PCR-based assay and disk diffusion assay of Enterococcus spp. We evaluated 30 clinical isolates of Enterococcus spp. Isolates were identified by MicrosScan system and PCR-based assay. The detection of antibiotic resistance genes (vancomycin, gentamicin, tetracycline and erythromycin) was also determined by PCR. Antimicrobial susceptibilities to vancomycin (30 µg), gentamicin (120 µg), tetracycline (30 µg) and erythromycin (15 µg) were tested by the automated system and disk diffusion method, and were interpreted according to the criteria recommended in CLSI guidelines. Concerning Enterococcus identification the general agreement between data obtained by the PCR method and by the automatic system was 90.0% (27/30). For all isolates of E. faecium and E. faecalis we observed 100% agreement. Resistance frequencies were higher in E. faecium than E. faecalis. The resistance rates obtained were higher for erythromycin (86.7%), vancomycin (80.0%), tetracycline (43.35) and gentamicin (33.3%). The correlation between disk diffusion and automation revealed an agreement for the majority of the antibiotics with category agreement rates of > 80%. The PCR-based assay, the van(A) gene was detected in 100% of vancomycin resistant enterococci. This assay is simple to conduct and reliable in the identification of clinically relevant enterococci. The data obtained reinforced the need for an improvement of the automated system to identify some enterococci. PMID:24626409

  8. A Novel Pupillometric Method for Indexing Word Difficulty in Individuals with and without Aphasia

    ERIC Educational Resources Information Center

    Chapman, Laura R.; Hallowell, Brooke

    2015-01-01

    Purpose: Cognitive effort is a clinically important facet of linguistic processing that is often overlooked in the assessment and treatment of people with aphasia (PWA). Furthermore, there is a paucity of valid ways to index cognitive effort in PWA. The construct of cognitive effort has been indexed for decades via pupillometry (measurement of…

  9. Development of a method to measure and compare hospital waste: the Premier hospital waste index.

    PubMed

    Lowe, Timothy J; Kroch, Eugene; Martin, John; Bankowitz, Richard

    2014-01-01

    The authors developed 15 measures and a comparative index to assist acute care facilities in identifying and monitoring clinical and administrative functions for health care waste reduction. Primary clinical and administrative data were collected from 261 acute care facilities contained within a database maintained by Premier Inc, spanning October 1, 2010, to September 30, 2011. The measures and 4 index models were tested using the Cronbach α coefficient and item-to-total and Spearman rank correlations. The final index model was validated using 52 facilities that had complete data. Analysis of the waste measures showed good internal reliability (α = .85) with some overlap. Index modeling found that data transformation using the standard deviation and adjusting for the proportional contribution of each measure normalized the distribution and produced a Spearman rank correlation of 0.95. The waste measures and index methodology provide a simple and reliable means to identify and reduce waste and compare and monitor facility performance. PMID:23687221

  10. Fungal Susceptibility of Polyurethanes

    PubMed Central

    Darby, Richard T.; Kaplan, Arthur M.

    1968-01-01

    One hundred laboratory-synthesized polyurethanes were tested by a mixed-culture petri dish method for susceptibility to fungus attack. Polyether polyurethanes were moderately to highly resistant to fungal attack, whereas all polyester polyurethanes tested were highly susceptible. The susceptibility of the polyethers was related to the number of adjacent methylene groups in the polymer chain. At least two such groups were required for appreciable attack to occur. The presence of side chains on the diol moiety of the polyurethane reduced susceptibility. Images Fig. 1 Fig. 2 Fig. 3 PMID:16349806

  11. Development and evaluation of a method for calculating the Healthy Eating Index-2005 using the Nutrition Data System for Research

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Objective: To develop and evaluate a method for calculating the Healthy Eating Index-2005 (HEI-2005) with the widely used Nutrition Data System for Research (NDSR) based on the method developed for use with the US Department of Agriculture’s (USDA) Food and Nutrient Dietary Data System (FNDDS) and M...

  12. Comparative evaluation of macrodilution and alamar colorimetric microdilution broth methods for antifungal susceptibility testing of yeast isolates.

    PubMed Central

    To, W K; Fothergill, A W; Rinaldi, M G

    1995-01-01

    A comparative evaluation of the macrodilution method and the Alamar colorimetric method for the susceptibility testing of amphotericin B, fluconazole, and flucytosine was conducted with 134 pathogenic yeasts. The clinical isolates included 28 Candida albicans, 17 Candida tropicalis, 15 Candida parapsilosis, 12 Candida krusei, 10 Candida lusitaniae, 9 Candida guilliermondii, 18 Torulopsis glabrata, and 25 Cryptococcus neoformans isolates. The macrodilution method was performed and interpreted according to the recommendations of the National Committee for Clinical Laboratory Standards (document M27-P), and the Alamar colorimetric method was performed according to the manufacturer's instructions. For the Alamar colorimetric method, MICs were determined at 24 and 48 h of incubation for Candida species and T. glabrata and at 48 and 72 h of incubation for C. neoformans. The overall agreement within +/- 1 dilution for Candida species and T. glabrata against the three antifungal agents was generally good, with the values for amphotericin B, fluconazole, and flucytosine being 85.3, 77.9, and 86.2%, respectively, at the 24-h readings and 69.3, 65.2, and 97.2%, respectively, at the 48-h readings. Most disagreement was noted with fluconazole against C. tropicalis and T. glabrata. Our studies indicate that determination of MICs at 24 h by the Alamar colorimetric method is a valid alternate method for testing amphotericin B, fluconazole, and flucytosine against Candida species but not for testing fluconazole against C. tropicalis and T. glabrata. For flucytosine, much better agreement can be demonstrated against Candida species and T. glabrata at the 48-h readings by the Alamar method.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8567901

  13. Using Taguchi method to optimize differential evolution algorithm parameters to minimize workload smoothness index in SALBP

    NASA Astrophysics Data System (ADS)

    Mozdgir, A.; Mahdavi, Iraj; Seyyedi, I.; Shiraqei, M. E.

    2011-06-01

    An assembly line is a flow-oriented production system where the productive units performing the operations, referred to as stations, are aligned in a serial manner. The assembly line balancing problem arises and has to be solved when an assembly line has to be configured or redesigned. The so-called simple assembly line balancing problem (SALBP), a basic version of the general problem, has attracted attention of researchers and practitioners of operations research for almost half a century. There are four types of objective functions which are considered to this kind of problem. The versions of SALBP may be complemented by a secondary objective which consists of smoothing station loads. Many heuristics have been proposed for the assembly line balancing problem due to its computational complexity and difficulty in identifying an optimal solution and so many heuristic solutions are supposed to solve this problem. In this paper a differential evolution algorithm is developed to minimize workload smoothness index in SALBP-2 and the algorithm parameters are optimized using Taguchi method.

  14. The role of method of production and resolution of the DEM on slope-units delineation for landslide susceptibility assessment - Ubaye Valley, French Alps case study

    NASA Astrophysics Data System (ADS)

    Schlögel, Romy; Marchesini, Ivan; Alvioli, Massimiliano; Reichenbach, Paola; Rossi, Mauro; Malet, Jean-Philippe

    2016-04-01

    Landslide susceptibility assessment forms the basis of any hazard mapping, which is one of the essential parts of quantitative risk mapping. For the same study area, different susceptibility maps can be achieved depending on the type of susceptibility mapping methods, mapping unit, and scale. In the Ubaye Valley (South French Alps), we investigate the effect of resolution and method of production of the DEM to delineate slope units for landslide susceptibility mapping method. Slope units delineation has been processed using multiple combinations of circular variance and minimum area size values, which are the input parameters for a new software for terrain partitioning. We rely on this method taking into account homogeneity of aspect direction inside each unit and inhomogeneity between different units. We computed slope units delineation for 5, 10 and 25 meters resolution DEM, and investigate statistical distributions of morphometric variables within the different polygons. Then, for each different slope units partitioning, we calibrated a landslide susceptibility model, considering landslide bodies and scarps as a dependent variable (binary response). This work aims to analyse the role of DEM resolution on slope-units delineation for landslide susceptibility assessment. Area Under the Curve of the Receiver Operating Characteristic is investigated for the susceptibility model calculations. In addition, we analysed further the performance of the Logistic Regression Model by looking at the percentage of significant variable in the statistical analyses. Results show that smaller slope units have a better chance of containing a smaller number of thematic and morphometric variables, allowing for an easier classification. Reliability of the models according to the DEM resolution considered as well as scarp area and landslides bodies presence/absence as dependent variable are discussed.

  15. Physical Basis for the Temperature-Based Melt-Index Method.

    NASA Astrophysics Data System (ADS)

    Ohmura, Atsumu

    2001-04-01

    The close relationship between air temperature measured at standard screen level and the rate of melt on snow and ice has been widely used to estimate the rate of melt. The parameterization of the melt rate using air temperature usually takes a simple form as a function of either the mean temperature for the relevant period or positive degree-day statistics. The computation provides the melt rate with sufficient accuracy for most practical purposes. Because of its simplicity, it is often called a crude method and is rated as inferior to other more sophisticated methods such as the energy balance method. The method is often used with the justification that temperature data are easily available or that obtaining energy balance fluxes is difficult. The physical process responsible for the temperature effect on the melt rate is often attributed to the sensible heat conduction from the atmosphere. The simulation capacity of the temperature-based melt-index method, however, is too good to be called crude and inferior. The author investigated physical processes that make the air temperature so effective a parameter for melt rate. Air temperature has a more profound influence on melt than previously has been acknowledged. The influence of air temperature through the turbulent sensible heat flux is limited, however. The air temperature information is transferred to the surface mainly through longwave atmospheric radiation, which is by far the most important heat source for melt. Under cloudless-sky conditions, as much as 60% of the atmospheric emission is derived from within the first 100 m and 90% from the first 1 km of the atmosphere. When the sky is overcast with the cloud bottom within the first 1 km, more than 90% originates within this layer between the surface and the bottom of the cloud. When the sky is overcast with the cloud bottom higher than 1 km, the first 1 km of the atmosphere still makes up about 70% of the longwave irradiance at the surface, for which the

  16. A Proxy Method for Estimation of EE-index using MAGDAS/CPMN Data

    NASA Astrophysics Data System (ADS)

    Ueno, T.; Yumoto, K.; Uozumi, T.; Numata, Y.; Group, M.

    2008-12-01

    EE-index (EDst, EU, and EL) is a new index proposed by Space Environment Research Center, Kyushu University (see Uozumi et al., 2008) to monitor temporal and long-term variations of the equatorial electrojet (EEJ). EU and EL mainly represent the range of EEJ and CEJ (equatorial counter electrojet) components, respectively. The baseline levels of EU and EL are obtained by averaging the H-component magnetic variations observed at the nightside (LT = 18-06) MAGDAS/CPMN stations along the magnetic equator. EDst, defined by Uozumi et al. (2008) fluctuates depending on the number of stations in the nightside sector (LT = 18-06). If the number is few, EDst may include some local fluctuations: the partial ring current component, substorm component and so on. Such local components cause some error in estimating the baseline level of EU or EL. Therefore, we need to use as many stations' data as possible in order to derive EU and EL properly. Pacific region is one of the most difficult areas to measure the magnetic field near the dip equator, because there are few islands. In the present paper, we developed a new method to use the data obtained from Ewa Beach (EWA; G. Lat. = 21.32N, G. Long. = 158.0W, Dip Lat. = 38.03), Hawaii, USA for estimation of EDst. EWA is not the equatorial station, but its nighttime H-component magnetic variations are found to be similar to those of Christmas Island (CXI; G. Lat. = 2.05N, G. Long. = 157.5W, Dip Lat. = 5.24), Kiribati. Data from EWA can be used as a proxy of that from CXI for monitoring temporal and long-term variations of the equatorial electrojet (EEJ) in real time. Acknowledgements: Authors appreciate Prof. Hisashi Utada of Earthquake Research Institute, University of Tokyo for supplying the magnetometer data from Christmas Island, Kiribati. Our deepest gratitude goes to all the members of the MAGDAS/CPMN project for their ceaseless support. Especially, we wish to thank the staffs of the observation stations: Dr. Baylie Damtie

  17. Influence of different susceptibility testing methods and media on determination of the relevant fluconazole minimum inhibitory concentrations for heavy trailing Candida isolates with low-high phenotype.

    PubMed

    Alp, Sehnaz; Sancak, Banu; Hascelik, Gulsen; Arikan, Sevtap

    2010-11-01

    We investigated the incidence of trailing growth with fluconazole in 101 clinical Candida isolates (49 C. albicans and 52 C. tropicalis) and tried to establish the convenient susceptibility testing method and medium for fluconazole minimum inhibitory concentration (MIC) determination. MICs were determined by CLSI M27-A2 broth microdilution (BMD) and Etest methods on RPMI-1640 agar supplemented with 2% glucose (RPG) and on Mueller-Hinton agar supplemented with 2% glucose and 0.5 μg ml(-1) methylene blue (GMB). BMD and Etest MICs were read at 24 and 48 h, and susceptibility categories were compared. All isolates were determined as susceptible with BMD, Etest-RPG and Etest-GMB at 24 h. While all isolates were interpreted as susceptible at 48 h on Etest-RPG and Etest-GMB, one C. albicans isolate was interpreted as susceptible-dose dependent (S-DD) and two C. tropicalis isolates were interpreted as resistant with BMD. On Etest-RPG, trailing growth caused widespread microcolonies within the inhibition zone and resulted in confusion in MIC determination. On Etest-GMB, because of the nearly absence of microcolonies within the zone of inhibition, MICs were evaluated more easily. We conclude that, for the determination of fluconazole MICs of trailing Candida isolates, the Etest method has an advantage over BMD and can be used along with this reference method. Moreover, GMB appears more beneficial than RPG for the fluconazole Etest. PMID:19563491

  18. Food Insecurity and Body Mass Index: A Longitudinal Mixed Methods Study, Chelsea, Massachusetts, 2009–2013

    PubMed Central

    Shen, Aileen; Oo, Sarah; Tilahun, Hailu; Cohen, Marya J.; Berkowitz, Seth A.

    2015-01-01

    Introduction Cross-sectional studies show an association between food insecurity and higher body mass index (BMI), but this finding has not been evaluated longitudinally. Patient perspectives on food choice in resource-constrained environments are not well understood. The objective of this study was to evaluate the longitudinal association between food insecurity and BMI. Methods This mixed methods study used both a retrospective matched cohort and focus groups. For the quantitative analysis, all patients in a community health center who reported food insecurity from October 2009 through March 2010 (n = 457) were followed through August 2013 and compared with controls matched by age, sex, and race/ethnicity (n = 1,974). We evaluated the association between food insecurity and change in BMI by using linear, mixed effects longitudinal models. The qualitative analysis included patients with food insecurity, stratified by BMI. Qualitative data were analyzed by using open coding and grounded theory. Results The mean age of participants was 51 years; 61% were women, and 73% were Hispanic. Baseline BMI was similar in food insecure participants and matched controls. After adjustment in longitudinal analyses, food insecurity was associated with greater increase in BMI (0.15 kg/m2 per year more than controls, P < .001). Themes identified in 4 focus groups included attitudes and knowledge about food, food access, and food practices. Participants with BMI of 30 kg/m2 or less highlighted skills such as budgeting and portion control. Conclusion Food insecurity is associated with increase in BMI. The skills of food insecure participants who were not obese, such as portion control and budgeting, may be useful in weight management interventions for vulnerable patients. PMID:26247425

  19. The Ocular Redness Index: A Novel Automated Method for Measuring Ocular Injection

    PubMed Central

    Amparo, Francisco; Wang, Haobing; Emami-Naeini, Parisa; Karimian, Parisa; Dana, Reza

    2013-01-01

    Purpose. To develop and validate a novel automated system to assess ocular redness (OR) in clinical images. Methods. We developed a novel software that quantifies OR in digital images based on a mathematic algorithm using a centesimal continuous scoring scale. Subsequently, we conducted a study to validate the scores obtained with this system by correlating them with those obtained by two physicians using two image-based comparative subjective scales, the Efron and the Validated Bulbar Redness (VBR) grading scales. Additionally, we evaluated the level of clinical agreement between the Ocular Redness Index (ORI) score and the two image-based methods by means of the Bland-Altman analysis. Main outcome measures included correlation and level of agreement between the ORI score, Efron score, and the VBR score. Results. One hundred and two clinical photographs of eyes with OR were evaluated. The ORI scores significantly correlated with the scores obtained by the two clinicians using the Efron (Observer 1, R = 0.925, P < 0.001; Observer 2, R = 0.857, P < 0.001), and VBR (Observer 1, R = 0.830, P < 0.001; Observer 2, R = 0.821, P < 0.001) scales. The Bland-Altman analysis revealed levels of disagreement of up to 30 and 27 units for the ORI–Efron and ORI–VBR score comparisons, respectively. Conclusions. The ORI provides an objective and continuous scale for evaluating ocular injection in an automated manner, and without need for a trained physician for scoring. The ORI may be used as a new alternative for objective OR evaluation in clinics and in clinical trials. PMID:23766472

  20. Project 6: Cumulative Risk Assessment Methods and Applications: Task 6.3. Applying Genetic and Epigenetic Data to Inform Susceptibility

    EPA Science Inventory

    Susceptibility is defined by the NRC (2009) as the capacity to be affected. A person can be at greater or less risk relative to population median risk because of susceptibility factors such as life stage, sex, genetics, socioeconomic status, prior exposure to chemicals, and non-c...

  1. Toward a better understanding of the gamma index: Investigation of parameters with a surface-based distance method

    SciTech Connect

    Li Heng; Dong Lei; Zhang Lifei; Yang, James N.; Gillin, Michael T.; Zhu, X. Ronald

    2011-12-15

    Purpose: The purpose of this work was to clarify the interactions between the parameters used in the {gamma} index with the surface-based distance method, which itself can be viewed as a generalized version of the {gamma} index. The examined parameters included the distance to agreement (DTA)/dose difference (DD) criteria, the percentage used as a passing criterion, and the passing percentage for given DTA/DD criteria. The specific aims of our work were (1) to understand the relationships between the parameters used in the {gamma} index, (2) to determine the detection limit, or the minimum detectable error, of the {gamma} index with a given set of parameters, and (3) to establish a procedure to determine parameters that are consistent with the capacity of an IMRT QA system. Methods: The surface-based distance technique with dose gradient factor was derived, and then the relationship between surface-based distance and {gamma} index was established. The dose gradient factor for plans and measurements of 10 IMRT patients, 10 spine stereotactic radiosurgery (SRS) patients, and 3 Radiological Physics Center (RPC) head and neck phantom were calculated and evaluated. The detection limits of the surface-based distance and {gamma} index methods were examined by introducing known shifts to the 10 IMRT plans. Results: The means of the dose gradient factors were 0.434 mm/% and 0.956 mm/% for the SRS and IMRT plans, respectively. Key quantities (including the mean and 90th and 99th percentiles of the distance distribution) of the surface-based distance distribution between two dose distributions were linearly proportional to the actual shifts. However, the passing percentage of the {gamma} index for a given set of DTA/DD criteria was not associated with the actual shift. For IMRT, using the standard quality assurance criteria of 3 mm/3% DTA/DD and a 90% passing rate, we found that the detection limit of the {gamma} index in terms of global shift was 4.07 mm/4.07 % without noise

  2. Novel Method Based on Real-Time Cell Analysis for Drug Susceptibility Testing of Herpes Simplex Virus and Human Cytomegalovirus.

    PubMed

    Piret, Jocelyne; Goyette, Nathalie; Boivin, Guy

    2016-08-01

    The plaque reduction assay (PRA) is the gold standard phenotypic method to determine herpes simplex virus (HSV) and human cytomegalovirus (HCMV) susceptibilities to antiviral drugs. However, this assay is subjective and labor intensive. Here, we describe a novel antiviral phenotypic method based on real-time cell analysis (RTCA) that measures electronic impedance over time. The effective drug concentrations that reduced by 50% (EC50s) the cytopathic effects induced by HSV-1 and HCMV were evaluated by both methods. The EC50s of acyclovir and foscarnet against a reference wild-type (WT) HSV-1 strain in Vero cells were, respectively, 0.5 μM and 32.6 μM by PRA and 0.8 μM and 93.6 μM by RTCA. The EC50 ratios for acyclovir against several HSV-1 thymidine kinase (TK) mutants were 101.8×, 73.4×, 28.8×, and 35.4× (PRA) and 18.0×, 52.0×, 5.5×, and 87.8× (RTCA) compared to those for the WT. The EC50 ratios for acyclovir and foscarnet against the HSV-1 TK/DNA polymerase mutant were 182.8× and 9.7× (PRA) and >125.0× and 10.8× (RTCA) compared to the WT. The EC50s of ganciclovir and foscarnet against WT HCMV strain AD169 in fibroblasts were, respectively, 1.6 μM and 27.8 μM by PRA and 5.0 μM and 111.4 μM by RTCA. The EC50 ratios of ganciclovir against the HCMV UL97 mutant were 3.8× (PRA) and 8.2× (RTCA) compared to those for the WT. The EC50 ratios of ganciclovir and foscarnet against the HCMV UL97/DNA polymerase mutant were 17.1× and 12.1× (PRA) and 14.7× and 4.6× (RTCA) compared to those for the WT. RTCA allows objective drug susceptibility testing of HSV and HCMV and could permit high-throughput screening of new antivirals. PMID:27252463

  3. Comparison of dynamic susceptibility contrast-MRI perfusion quantification methods in the presence of delay and dispersion

    NASA Astrophysics Data System (ADS)

    Maan, Bianca; Simões, Rita Lopes; Meijer, Frederick J. A.; Klaas Jan Renema, W.; Slump, Cornelis H.

    2011-03-01

    The perfusion of the brain is essential to maintain brain function. Stroke is an example of a decrease in blood flow and reduced perfusion. During ischemic stroke the blood flow to tissue is hampered due to a clot inside a vessel. To investigate the recovery of stroke patients, follow up studies are necessary. MRI is the preferred imaging modality for follow up because of the absence of radiation dose concerns, contrary to CT. Dynamic Susceptibility Contrast (DSC) MRI is an imaging technique used for measuring perfusion of the brain, however, is not standard applied in the clinical routine due to lack of immediate patient benefit. Several post processing algorithms are described in the literature to obtain cerebral blood flow (CBF). The quantification of CBF relies on the deconvolution of a tracer concentration-time curve in an arterial and a tissue voxel. There are several methods to obtain this deconvolution based on singular-value decomposition (SVD). This contribution describes a comparison between the different approaches as currently there is no best practice for (all) clinical relevant situations. We investigate the influence of tracer delay, dispersion and recirculation on the performance of the methods. In the presence of negative delays, the truncated SVD approach overestimates the CBF. Block-circulant and reformulated SVD are delay-independent. Due to its delay dependent behavior, the truncated SVD approach performs worse in the presence of dispersion as well. However all SVD approaches are dependent on the amount of dispersion. Moreover, we observe that the optimal truncation parameter varies when recirculation is added to noisy data, suggesting that, in practice, these methods are not immune to tracer recirculation. Finally, applying the methods to clinical data resulted in a large variability of the CBF estimates. Block-circulant SVD will work in all situations and is the method with the highest potential.

  4. Use of indexed historical floods in flood frequency estimation with Fuzzy Bayesian methods

    NASA Astrophysics Data System (ADS)

    Salinas, Jose; Viglione, Alberto; Kiss, Andrea; Bloeschl, Guenter

    2015-04-01

    Efforts of the historical environmental extremes community during the last decades have resulted in the existence of long time series of floods, for example in Central Europe and the Mediterranean region, which in some cases range longer than 500 years in the past. In most of the cases the flood time series are presented in terms of indices, representing a combination of socio-economic indicators for the flood impact, e.g. economic damage, flood duration and extension, ... In hydrological engineering, historical floods are very useful because they give additional information which will reduce the uncertainty in estimates of discharges with low annual exceedance probabilities, i.e. with high return periods. In order to use the historical floods in formal flood frequency analysis, the precise value of the peak discharges would ideally be known, but as commented, they are most usually given in term of indices. This work presents a novel method on how to obtain a prior distribution for the parameters of the annual peak discharges distribution from indexed historical floods time series. The prior distribution is incorporated in the flood frequency estimation via Bayesian methods (see e.g. Viglione et al., 2013) in order to reduce the uncertainties in the design flood estimates. The historical data used is subject to a high degree of uncertainty and unpreciseness. In this sense, a framework is presented where the discharge thresholds between flood indices are modeled as fuzzy numbers. These fuzzy thresholds will define a fuzzy prior distribution, which will requires to apply Fuzzy Bayesian Inference (Viertl, 2008ab) to obtain fuzzy credibility intervals for the design floods. Viertl, R. (2008a) Foundations of Fuzzy Bayesian Inference, Journal of Uncertain Systems, 2, 187-191. Viertl, R. (2008b) Fuzzy Bayesian Inference. In: Soft Methods For Handling Variability And Imprecision. Advances In Soft Computing. Vol. 48. Springer-Verlag Berlin, pp 10-15. Viglione, A., R. Merz

  5. The long-run dynamic relationship between exchange rate and its attention index: Based on DCCA and TOP method

    NASA Astrophysics Data System (ADS)

    Wang, Xuan; Guo, Kun; Lu, Xiaolin

    2016-07-01

    The behavior information of financial market plays a more and more important role in modern economic system. The behavior information reflected in INTERNET search data has already been used in short-term prediction for exchange rate, stock market return, house price and so on. However, the long-run relationship between behavior information and financial market fluctuation has not been studied systematically. Further, most traditional statistic methods and econometric models could not catch the dynamic and non-linear relationship. An attention index of CNY/USD exchange rate is constructed based on search data from 360 search engine of China in this paper. Then the DCCA and Thermal Optimal Path methods are used to explore the long-run dynamic relationship between CNY/USD exchange rate and the corresponding attention index. The results show that the significant interdependency exists and the change of exchange rate is 1-2 days lag behind the attention index.

  6. The Dust Storm Index (DSI): A method for monitoring broadscale wind erosion using meteorological records

    NASA Astrophysics Data System (ADS)

    O'Loingsigh, T.; McTainsh, G. H.; Tews, E. K.; Strong, C. L.; Leys, J. F.; Shinkfield, P.; Tapper, N. J.

    2014-03-01

    Wind erosion of soils is a natural process that has shaped the semi-arid and arid landscapes for millennia. This paper describes the Dust Storm Index (DSI); a methodology for monitoring wind erosion using Australian Bureau of Meteorology (ABM) meteorological observational data since the mid-1960s (long-term), at continental scale. While the 46 year length of the DSI record is its greatest strength from a wind erosion monitoring perspective, there are a number of technical challenges to its use because when the World Meteorological Organisation (WMO) recording protocols were established the use of the data for wind erosion monitoring was never intended. Data recording and storage protocols are examined, including the effects of changes to the definition of how observers should interpret and record dust events. A method is described for selecting the 180 long-term ABM stations used in this study and the limitations of variable observation frequencies between stations are in part resolved. The rationale behind the DSI equation is explained and the examples of temporal and spatial data visualisation products presented include; a long term national wind erosion record (1965-2011), continental DSI maps, and maps of the erosion event types that are factored into the DSI equation. The DSI is tested against dust concentration data and found to provide an accurate representation of wind erosion activity. As the ABM observational records used here were collected according to WMO protocols, the DSI methodology could be used in all countries with WMO-compatible meteorological observation and recording systems.

  7. Method of producing optical quality glass having a selected refractive index

    DOEpatents

    Poco, John F.; Hrubesh, Lawrence W.

    2000-01-01

    Optical quality glass having a selected refractive index is produced by a two stage drying process. A gel is produced using sol-gel chemistry techniques and first dried by controlled evaporation until the gel volume reaches a pre-selected value. This pre-selected volume determines the density and refractive index of the finally dried gel. The gel is refilled with solvent in a saturated vapor environment, and then dried again by supercritical extraction of the solvent to form a glass. The glass has a refractive index less than the full density of glass, and the range of achievable refractive indices depends on the composition of the glass. Glasses having different refractive indices chosen from an uninterrupted range of values can be produced from a single precursor solution.

  8. Application of the scaling index method to μCT images of human trabecular bone for the characterization of biomechanical strength

    NASA Astrophysics Data System (ADS)

    Monetti, Roberto A.; Bauer, Jan; Müller, Dirk; Rummeny, Ernst; Matsuura, Maiko; Eckstein, Felix; Link, Thomas; Räth, Christoph

    2007-03-01

    Osteoporosis is a metabolic bone disorder characterized by the loss of bone mineral density (BMD) and the deterioration of the bone micro-architecture. Rarefied bone structures are more susceptible to fractures which are the worst complications of osteoporosis. Here, we apply a structure characterization method, namely the Scaling Index Method, to micro-computed tomographic (μ-CT) images of the distal radius and extract 3D nonlinear structure measures to assess the biomechanical properties of trabecular bone. Biomechanical properties were quantified by the maximum compressive strength (MCS) obtained in a biomechanical test and bone mineral density (BMD) was calculated using dual X-ray absorptiometry (DXA). μ-CT images allow for the application of two different modalities of the SIM which differ in the dimensional embedding of the image. Both representations lead to similar correlation coefficients with MCS which are significantly better than the ones obtained using standard 3D morphometric parameters and comparable to the result given by BMD. The analysis of μ-CT images based on the SIM allows for a sharp distinction of the different structural elements which compose the trabecular bone network.

  9. Retrieval of size and refractive index of spherical particles by multiangle light scattering: neural network method application.

    PubMed

    Berdnik, Vladimir V; Loiko, Valery A

    2009-11-10

    A method to retrieve the radius and the relative refractive index of spherical homogeneous nonabsorbing particles by multiangle scattering is proposed. It is based on the formation of noise-resistant functionals of the scattered intensity, which are invariant with respect to the linear homogeneous transformations of an intensity-based signal and approximation of the retrieved parameters' dependence on the functionals by a feed-forward neural network. The neural network was trained by minimization of the mean squared relative error in the range of particle radii from 0.6 mkm up to 13.6 mkm and relative refractive index from 1.015 up to 1.28. In comparison with training on a minimum of the mean squared error, this method enables one to increase the accuracy of the radius retrieval in the range of radii from 0.6 to 2 microm and refractive index in the range from 1.015 to 1.1. The values of intensity of light scattered in the interval of angles 10 degrees-60 degrees are used as input data. If the measurement error is 20%, the mean errors of the radius and relative refractive index are 0.8% and 7%, respectively. The results obtained by the proposed method and by the trial and error method with published experimental data (measured with a scanning flow cytometer) are compared. The maximal difference in the retrieval results of radius and the relative refractive index of particles obtained by both methods is under 5%. PMID:19904314

  10. In vitro antimicrobial activity of benzoyl peroxide against Propionibacterium acnes assessed by a novel susceptibility testing method.

    PubMed

    Okamoto, Kazuaki; Ikeda, Fumiaki; Kanayama, Shoji; Nakajima, Akiko; Matsumoto, Tatsumi; Ishii, Ritsuko; Umehara, Masatoshi; Gotoh, Naomasa; Hayashi, Naoki; Iyoda, Takako; Matsuzaki, Kaoru; Matsumoto, Satoru; Kawashima, Makoto

    2016-06-01

    Benzoyl peroxide (BPO), a therapeutic agent for acne vulgaris, was assessed for in vitro antimicrobial activity against Propionibacterium acnes using a novel broth microdilution testing that improved BPO solubility. We searched for a suitable culture medium to measure the minimum inhibitory concentration (MIC) of BPO against P. acnes and finally found the Gifu anaerobic medium (GAM) broth supplemented with 0.1(v/v)% glycerol and 2(v/v)% Tween 80, in which BPO dissolved up to 1250 μg/mL and P. acnes grew well. The MICs and minimum bactericidal concentrations (MBCs) of BPO against 44 clinical isolates of P. acnes collected from Japanese patients with acne vulgaris were determined by our testing method using the supplemented GAM broth. The MICs of BPO were 128 or 256 μg/mL against all isolates of P. acnes regardless of susceptibility to nadifloxacin or clindamycin. The MBCs of BPO were also 128 or 256 μg/mL against the same isolates. Moreover, BPO at the MIC showed a rapid bactericidal activity against P. acnes ATCC11827 in time-kill assay. In conclusion, we could develop a novel assay for the MIC and MBC determinations of BPO against P. acnes, which is reliable and reproducible as a broth microdilution testing and the present results suggest that BPO has a potent bactericidal activity against P. acnes. PMID:26806150