Estudo comparativo dos óleos voláteis de algumas espécies de Piperaceae

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J.M.O. Mesquita

Full Text Available O presente trabalho teve por objetivo a análise comparativa dos óleos voláteis de espécies da família Piperaceae. As espécies estudadas foram as seguintes: Piper aduncum, P. amalago, P. arboreum, P. cernuum, P. hispidum, P. regnelii, P. submarginalum, P. vicosanum e Pothomorphe umbellata. A análise dos óleos voláteis foi efetuada pela combinação de técnicas de Cromatografia de Fase Gasosa (CG e de Cromatografia de Fase Gasosa acoplada a Espectrometria de Massa (CG/EM. A porcentagem de identificação dos constituintes nas análises dos óleos voláteis de Piper aduncum, P. amalago, P. vicosanum, P. submarginalum e Pothomorphe umbellata, atingiu valores superiores a 80%. Houve predominância de compostos de natureza sesquiterpênica nas composições químicas das espécies analisadas, com exceção de P. hispidum, P. submarginalum e P. vicosanum onde a predominância na composição foi de monoterpenos. Pelos dados apresentados observou-se que, dentre os compostos majoritários, os mais freqüentes, nas 9 espécies estudadas, foram beta-pineno (9/9 e espatulenol (9/9, seguidos por E-cariofileno (8/9, óxido de cariofileno (8/9, germacreno D (7/9, alfa-pineno (7/9 e limoneno (6/9. Pela primeira vez se relata a composição dos óleos voláteis de P. submarginalum e P vicosanum.

Spherical gradient-index lenses as perfect imaging and maximum power transfer devices.

Science.gov (United States)

Gordon, J M

2000-08-01

Gradient-index lenses can be viewed from the perspectives of both imaging and nonimaging optics, that is, in terms of both image fidelity and achievable flux concentration. The simple class of gradient-index lenses with spherical symmetry, often referred to as modified Luneburg lenses, is revisited. An alternative derivation for established solutions is offered; the method of Fermat's strings and the principle of skewness conservation are invoked. Then these nominally perfect imaging devices are examined from the additional vantage point of power transfer, and the degree to which they realize the thermodynamic limit to flux concentration is determined. Finally, the spherical gradient-index lens of the fish eye is considered as a modified Luneburg lens optimized subject to material constraints.

Frugivoria e dispersão de sementes pelo lagarto teiú Tupinambis merianae (Reptilia: Teiidae)

OpenAIRE

Castro,Everaldo Rodrigo de; Galetti,Mauro

2004-01-01

Os lagartos teiús possuem uma dieta generalista, podendo agir como importantes dispersores de sementes em florestas semidecíduas do sudeste do Brasil. Foram estudadas a frugivoria e a dispersão de sementes de lagartos teiús usando animais em cativeiro, através da oferta de frutos de uma floresta semidecídua. Frutos de trinta espécies vegetais foram oferecidos aos lagartos em cativeiro, com diâmetro variando de 0,81 a 10,0 cm. Não foram encontradas diferenças estatísticas na germinação entre a...

School Technology Leadership in a Spanish Secondary School: The TEI Model

Science.gov (United States)

Gallego-Arrufat, María-Jesús; Gutiérrez-Santiuste, Elba; Campaña-Jiménez, Rafael Luis

2017-01-01

This study analyzes the perception that teachers and management team members in secondary school education have of "technology-based educational innovation" (TEI). Two questionnaires and in-depth interviews permit us to analyze leaders' perspective of planning, development, and evaluation. The school leaders' view diverges from that of…

WEATHER INDEX- THE BASIS OF WEATHER DERIVATIVES

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Botos Horia Mircea

2011-07-01

Full Text Available This paper approaches the subject of Weather Derivatives, more exactly their basic element the weather index. The weather index has two forms, the Heating Degree Day (HDD and the Cooling Degree Day (CDD. We will try to explain their origin, use and the relationship between the two forms of the index. In our research we started from the analysis of the weather derivatives and what they are based on. After finding out about weather index, we were interested in understanding exactly how they work and how they influence the value of the contract. On the national level the research in the field is scares, but foreign materials available. The study for this paper was based firstly on reading about Weather Derivative, and then going in the meteorogical field and determining the way by which the indices were determined. After this, we went to the field with interest in the indices, such as the energy and gas industries, and figured out how they determined the weather index. For the examples we obtained data from the weather index database, and calculated the value for the period. The study is made on a period of five years, in 8 cities of the European Union. The result of this research is that we can now understand better the importance of the way the indices work and how they influence the value of the Weather Derivatives. This research has an implication on the field of insurance, because of the fact that weather derivative are at the convergence point of the stock markets and the insurance market. The originality of the paper comes from the personal touch given to the theoretical aspect and through the analysis of the HDD and CDD index in order to show their general behaviour and relationship.

INTEGRATION OF IMAGE-DERIVED AND POS-DERIVED FEATURES FOR IMAGE BLUR DETECTION

Directory of Open Access Journals (Sweden)

T.-A. Teo

2016-06-01

Full Text Available The image quality plays an important role for Unmanned Aerial Vehicle (UAV’s applications. The small fixed wings UAV is suffering from the image blur due to the crosswind and the turbulence. Position and Orientation System (POS, which provides the position and orientation information, is installed onto an UAV to enable acquisition of UAV trajectory. It can be used to calculate the positional and angular velocities when the camera shutter is open. This study proposes a POS-assisted method to detect the blur image. The major steps include feature extraction, blur image detection and verification. In feature extraction, this study extracts different features from images and POS. The image-derived features include mean and standard deviation of image gradient. For POS-derived features, we modify the traditional degree-of-linear-blur (blinear method to degree-of-motion-blur (bmotion based on the collinear condition equations and POS parameters. Besides, POS parameters such as positional and angular velocities are also adopted as POS-derived features. In blur detection, this study uses Support Vector Machines (SVM classifier and extracted features (i.e. image information, POS data, blinear and bmotion to separate blur and sharp UAV images. The experiment utilizes SenseFly eBee UAV system. The number of image is 129. In blur image detection, we use the proposed degree-of-motion-blur and other image features to classify the blur image and sharp images. The classification result shows that the overall accuracy using image features is only 56%. The integration of image-derived and POS-derived features have improved the overall accuracy from 56% to 76% in blur detection. Besides, this study indicates that the performance of the proposed degree-of-motion-blur is better than the traditional degree-of-linear-blur.

Cardiac magnetic resonance imaging-derived pulmonary artery distensibility index correlates with pulmonary artery stiffness and predicts functional capacity in patients with pulmonary arterial hypertension

International Nuclear Information System (INIS)

Kang, Ki-Woon; Chang, Hyuk-Jae; Kim, Young-Jin; Choi, Byoung-Wook; Yang, Woo-In; Shim, Chi-Young; Ha, Jongwon; Chung, Namsik; Lee, Hye-Sun

2011-01-01

Increased stiffness of the pulmonary vascular bed is known to increase mortality in patients with pulmonary arterial hypertension (PAH); and pulmonary artery (PA) stiffness is also thought to be associated with exercise capacity. The purpose of the present study was to investigate whether cardiac magnetic resonance imaging (CMRI)-derived PA distensibility index correlates with PA stiffness estimated on right heart catheterization (RHC) and predicts functional capacity (FC) in patients with PAH. Thirty-five consecutive PAH patients (23% male, mean age, 44±13 years; 69% idiopathic) underwent CMRI, RHC, and 6-min walk test (6MWT). PA distensibility indices were derived from cross-sectional area change (%) in the transverse view, perpendicular to the axis of the main PA, on CMRI [(maximum area-minimum area)/minimum area during cardiac cycle]. Among the PA stiffness indices, pulmonary vascular resistance (PVR) and PA capacitance were calculated using hemodynamic dataset from RHC. CMRI-derived PA distensibility was inversely correlated with PVR (R 2 =0.34, P 2 =0.35, P 2 =0.61, P<0.001). Furthermore, PA distensibility <20% predicted poor FC (<400 m in 6MWT) with a sensitivity of 82% and a specificity of 94%. Non-invasive CMRI-derived PA distensibility index correlates with PA stiffness and can predict FC in patients with PAH. (author)

IDIOS: An innovative index for evaluating dental imaging-based osteoporosis screening indices

Energy Technology Data Exchange (ETDEWEB)

Barngkgei, Imad; Al Haffar, Iyad; Khattab, Razan [Faculty of Dentistry, Damascus University, Damascus (Syrian Arab Republic); Halboub, Esam; Almashraqi, Abeer Abdulkareem [Dept. of Maxillofacial Surgery and Diagnostic Sciences, College of Dentistry, Jazan University, Jazan (Saudi Arabia)

2016-09-15

The goal of this study was to develop a new index as an objective reference for evaluating current and newly developed indices used for osteoporosis screening based on dental images. Its name; IDIOS, stands for Index of Dental-imaging Indices of Osteoporosis Screening. A comprehensive PubMed search was conducted to retrieve studies on dental imaging-based indices for osteoporosis screening. The results of the eligible studies, along with other relevant criteria, were used to develop IDIOS, which has scores ranging from 0 (0%) to 15 (100%). The indices presented in the studies we included were then evaluated using IDIOS. The 104 studies that were included utilized 24, 4, and 9 indices derived from panoramic, periapical, and computed tomographic/cone-beam computed tomographic techniques, respectively. The IDIOS scores for these indices ranged from 0 (0%) to 11.75 (78.32%). IDIOS is a valuable reference index that facilitates the evaluation of other dental imaging-based osteoporosis screening indices. Furthermore, IDIOS can be utilized to evaluate the accuracy of newly developed indices.

IDIOS: An innovative index for evaluating dental imaging-based osteoporosis screening indices.

Science.gov (United States)

Barngkgei, Imad; Halboub, Esam; Almashraqi, Abeer Abdulkareem; Khattab, Razan; Al Haffar, Iyad

2016-09-01

The goal of this study was to develop a new index as an objective reference for evaluating current and newly developed indices used for osteoporosis screening based on dental images. Its name; IDIOS, stands for Index of Dental-imaging Indices of Osteoporosis Screening. A comprehensive PubMed search was conducted to retrieve studies on dental imaging-based indices for osteoporosis screening. The results of the eligible studies, along with other relevant criteria, were used to develop IDIOS, which has scores ranging from 0 (0%) to 15 (100%). The indices presented in the studies we included were then evaluated using IDIOS. The 104 studies that were included utilized 24, 4, and 9 indices derived from panoramic, periapical, and computed tomographic/cone-beam computed tomographic techniques, respectively. The IDIOS scores for these indices ranged from 0 (0%) to 11.75 (78.32%). IDIOS is a valuable reference index that facilitates the evaluation of other dental imaging-based osteoporosis screening indices. Furthermore, IDIOS can be utilized to evaluate the accuracy of newly developed indices.

IDIOS: An innovative index for evaluating dental imaging-based osteoporosis screening indices

International Nuclear Information System (INIS)

Barngkgei, Imad; Al Haffar, Iyad; Khattab, Razan; Halboub, Esam; Almashraqi, Abeer Abdulkareem

2016-01-01

The goal of this study was to develop a new index as an objective reference for evaluating current and newly developed indices used for osteoporosis screening based on dental images. Its name; IDIOS, stands for Index of Dental-imaging Indices of Osteoporosis Screening. A comprehensive PubMed search was conducted to retrieve studies on dental imaging-based indices for osteoporosis screening. The results of the eligible studies, along with other relevant criteria, were used to develop IDIOS, which has scores ranging from 0 (0%) to 15 (100%). The indices presented in the studies we included were then evaluated using IDIOS. The 104 studies that were included utilized 24, 4, and 9 indices derived from panoramic, periapical, and computed tomographic/cone-beam computed tomographic techniques, respectively. The IDIOS scores for these indices ranged from 0 (0%) to 11.75 (78.32%). IDIOS is a valuable reference index that facilitates the evaluation of other dental imaging-based osteoporosis screening indices. Furthermore, IDIOS can be utilized to evaluate the accuracy of newly developed indices

Impact of image noise on gamma index calculation

International Nuclear Information System (INIS)

Chen, M; Mo, X; Parnell, D; Olivera, G; Galmarini, D; Lu, W

2014-01-01

Purpose: The Gamma Index defines an asymmetric metric between the evaluated image and the reference image. It provides a quantitative comparison that can be used to indicate sample-wised pass/fail on the agreement of the two images. The Gamma passing/failing rate has become an important clinical evaluation tool. However, the presence of noise in the evaluated and/or reference images may change the Gamma Index, hence the passing/failing rate, and further, clinical decisions. In this work, we systematically studied the impact of the image noise on the Gamma Index calculation. Methods: We used both analytic formulation and numerical calculations in our study. The numerical calculations included simulations and clinical images. Three different noise scenarios were studied in simulations: noise in reference images only, in evaluated images only, and in both. Both white and spatially correlated noises of various magnitudes were simulated. For clinical images of various noise levels, the Gamma Index of measurement against calculation, calculation against measurement, and measurement against measurement, were evaluated. Results: Numerical calculations for both the simulation and clinical data agreed with the analytic formulations, and the clinical data agreed with the simulations. For the Gamma Index of measurement against calculation, its distribution has an increased mean and an increased standard deviation as the noise increases. On the contrary, for the Gamma index of calculation against measurement, its distribution has a decreased mean and stabilized standard deviation as the noise increases. White noise has greater impact on the Gamma Index than spatially correlated noise. Conclusions: The noise has significant impact on the Gamma Index calculation and the impact is asymmetric. The Gamma Index should be reported along with the noise levels in both reference and evaluated images. Reporting of the Gamma Index with switched roles of the images as reference and

Impact of Image Noise on Gamma Index Calculation

Science.gov (United States)

Chen, M.; Mo, X.; Parnell, D.; Olivera, G.; Galmarini, D.; Lu, W.

2014-03-01

Purpose: The Gamma Index defines an asymmetric metric between the evaluated image and the reference image. It provides a quantitative comparison that can be used to indicate sample-wised pass/fail on the agreement of the two images. The Gamma passing/failing rate has become an important clinical evaluation tool. However, the presence of noise in the evaluated and/or reference images may change the Gamma Index, hence the passing/failing rate, and further, clinical decisions. In this work, we systematically studied the impact of the image noise on the Gamma Index calculation. Methods: We used both analytic formulation and numerical calculations in our study. The numerical calculations included simulations and clinical images. Three different noise scenarios were studied in simulations: noise in reference images only, in evaluated images only, and in both. Both white and spatially correlated noises of various magnitudes were simulated. For clinical images of various noise levels, the Gamma Index of measurement against calculation, calculation against measurement, and measurement against measurement, were evaluated. Results: Numerical calculations for both the simulation and clinical data agreed with the analytic formulations, and the clinical data agreed with the simulations. For the Gamma Index of measurement against calculation, its distribution has an increased mean and an increased standard deviation as the noise increases. On the contrary, for the Gamma index of calculation against measurement, its distribution has a decreased mean and stabilized standard deviation as the noise increases. White noise has greater impact on the Gamma Index than spatially correlated noise. Conclusions: The noise has significant impact on the Gamma Index calculation and the impact is asymmetric. The Gamma Index should be reported along with the noise levels in both reference and evaluated images. Reporting of the Gamma Index with switched roles of the images as reference and

Image Vector Quantization codec indexes filtering

Directory of Open Access Journals (Sweden)

Lakhdar Moulay Abdelmounaim

2012-01-01

Full Text Available Vector Quantisation (VQ is an efficient coding algorithm that has been widely used in the field of video and image coding, due to its fast decoding efficiency. However, the indexes of VQ are sometimes lost because of signal interference during the transmission. In this paper, we propose an efficient estimation method to conceal and recover the lost indexes on the decoder side, to avoid re-transmitting the whole image again. If the image or video has the limitation of a period of validity, re-transmitting the data wastes the resources of time and network bandwidth. Therefore, using the originally received correct data to estimate and recover the lost data is efficient in time-constrained situations, such as network conferencing or mobile transmissions. In nature images, the pixels are correlated with their neighbours and VQ partitions the image into sub-blocks and quantises them to the indexes that are transmitted; the correlation between adjacent indexes is very strong. There are two parts of the proposed method. The first is pre-processing and the second is an estimation process. In pre-processing, we modify the order of codevectors in the VQ codebook to increase the correlation among the neighbouring vectors. We then use a special filtering method in the estimation process. Using conventional VQ to compress the Lena image and transmit it without any loss of index can achieve a PSNR of 30.429 dB on the decoder. The simulation results demonstrate that our method can estimate the indexes to achieve PSNR values of 29.084 and 28.327 dB when the loss rate is 0.5% and 1%, respectively.

Transformation invariant image indexing and retrieval for image databases

NARCIS (Netherlands)

Gevers, Th.; Smeulders, A.W.M.

1994-01-01

This paper presents a novel design of an image database system which supports storage, indexing and retrieval of images by content. The image retrieval methodology is based on the observation that images can be discriminated by the presence of image objects and their spatial relations. Images in the

Estimation of leaf area index in cereal crops using red-green images

DEFF Research Database (Denmark)

Kirk, Kristian; Andersen, Hans Jørgen; Thomsen, Anton G

2009-01-01

A new method for estimating the leaf area index (LAI) in cereal crops based on red-green images taken from above the crop canopy is introduced. The proposed method labels pixels into vegetation and soil classes using a combination of greenness and intensity derived from the red and green colour b...

Live Coral Cover Index Testing and Application with Hyperspectral Airborne Image Data

Directory of Open Access Journals (Sweden)

Karen E. Joyce

2013-11-01

Full Text Available Coral reefs are complex, heterogeneous environments where it is common for the features of interest to be smaller than the spatial dimensions of imaging sensors. While the coverage of live coral at any point in time is a critical environmental management issue, image pixels may represent mixed proportions of coverage. In order to address this, we describe the development, application, and testing of a spectral index for mapping live coral cover using CASI-2 airborne hyperspectral high spatial resolution imagery of Heron Reef, Australia. Field surveys were conducted in areas of varying depth to quantify live coral cover. Image statistics were extracted from co-registered imagery in the form of reflectance, derivatives, and band ratios. Each of the spectral transforms was assessed for their correlation with live coral cover, determining that the second derivative around 564 nm was the most sensitive to live coral cover variations(r2 = 0.63. Extensive field survey was used to transform relative to absolute coral cover, which was then applied to produce a live coral cover map of Heron Reef. We present the live coral cover index as a simple and viable means to estimate the amount of live coral over potentially thousands of km2 and in clear-water reefs.

NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Smoothed Normalized Difference Vegetation Index (NDVI) from NDE

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The Visible Infrared Imaging Radiometer Suite (VIIRS) Smoothed Normalized Difference Vegetation Index (NDVI) from NDE is a weekly product derived from the VIIRS...

Estimation of leaf area index in cereal crops using red–green images

DEFF Research Database (Denmark)

Nielsen, Kristian Kirk; Andersen, Hans Jørgen; Thomsen, Anton

2009-01-01

A new method for estimating the leaf area index (LAI) in cereal crops based on red–green images taken from above the crop canopy is introduced. The proposed method labels pixels into vegetation and soil classes using a combination of greenness and intensity derived from the red and green colour b....... Conclusions Acknowledgements Appendix. Modelling the correlation between greenness and brightness References   Fig. 1. Simulated image of a vegetation canopy (left), with distribution of pixel greenness and brightness (right). View Within Article...

Substâncias voláteis em mel floral e mel de melato

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CAMPOS Gisélia

2000-01-01

Full Text Available Embora pareça existir um "flavor" característico de mel, a grande variedade de flores disponíveis para a abelha, possibilita uma grande diversidade de flavor e aroma, indicando a presença de vários componentes voláteis. Alguns destes dependem da fisiologia da abelha, dos procedimentos após a colheita e no mel de melato há também a interferência de insetos sugadores e das formigas. Várias substâncias voláteis já foram identificadas, sendo algumas características de determinados méis uniflorais. Com o objetivo de encontrar uma substância volátil característica do mel de melato, seis amostras deste tipo de mel e seis amostras de mel floral foram analisadas usando extração por arraste de gás hidrogênio e cromatografia a gás acoplada a espectrometria de massas. Ácido acético foi encontrado em quatro amostras de mel de melato e em uma amostra de mel floral porém, com menor abundância.

Digitized hand-wrist radiographs: comparison of subjective and software-derived image quality at various compression ratios.

Science.gov (United States)

McCord, Layne K; Scarfe, William C; Naylor, Rachel H; Scheetz, James P; Silveira, Anibal; Gillespie, Kevin R

2007-05-01

The objectives of this study were to compare the effect of JPEG 2000 compression of hand-wrist radiographs on observer image quality qualitative assessment and to compare with a software-derived quantitative image quality index. Fifteen hand-wrist radiographs were digitized and saved as TIFF and JPEG 2000 images at 4 levels of compression (20:1, 40:1, 60:1, and 80:1). The images, including rereads, were viewed by 13 orthodontic residents who determined the image quality rating on a scale of 1 to 5. A quantitative analysis was also performed by using a readily available software based on the human visual system (Image Quality Measure Computer Program, version 6.2, Mitre, Bedford, Mass). ANOVA was used to determine the optimal compression level (P quality. When we used quantitative indexes, the JPEG 2000 images had lower quality at all compression ratios compared with the original TIFF images. There was excellent correlation (R2 >0.92) between qualitative and quantitative indexes. Image Quality Measure indexes are more sensitive than subjective image quality assessments in quantifying image degradation with compression. There is potential for this software-based quantitative method in determining the optimal compression ratio for any image without the use of subjective raters.

A aplicação das tecnologias de prototipagem rápida na confecção de matrizes táteis

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Maria Engracinda dos Santos Ferreira

Full Text Available No Brasil, as matrizes necessárias para a reprodução de mapas táteis ainda são produzidas de modo artesanal e demorado. Este artigo apresenta uma proposta de confeccionar matrizes táteis a partir de diferentes tecnologias de prototipagem rápida e determinar a sua viabilidade na automação do processo de fabricação das matrizes táteis. Primeiro foi realizada uma revisão na literatura sobre o assunto para verificar, dentro dos processos de prototipagem existentes, quais podem ser utilizados na confecção de matrizes táteis, principalmente quanto a capacidade da matéria-prima em resistir à pressão e altas temperaturas durante o processo de produção dos mapas finais. Apesar destes requisitos operacionais constituírem uma desvantagem em termos de equipamento especializado, o principal ganho no emprego destes poderá ser obtido pela garantia de geração de matrizes idênticas e flexibilidade na escolha de padrões. Os primeiros protótipos foram produzidos em poliuretano, pó de gesso e Uriol, em dois processos: impressoras 3D e máquinas fresadoras. As matrizes foram feitas apenas com o uso da fresadora, com poliuretano e MDF como matéria-prima. Foram conduzidos testes de percepção tátil pelo revisor de Braille do Instituto Benjamin Constant, seguindo metodologia padrão adotada pela instituição em todos os materiais produzidos.

Auto-indexing of oscillation images

International Nuclear Information System (INIS)

Higashi, Tsuneyuki

1990-01-01

A method is presented which indexes spots recorded on single oscillation images without any a priori knowledge of cell parameters. The strategy is similar to that used in four-circle diffractometry and the method works in a fully automatic manner. It is applicable to multiple oscillation images or multiple stills. A complementary method is also described to obtain orientation angles for the case where cell parameters have already been determined. (orig.)

MRI-derived Restriction Spectrum Imaging Cellularity Index is Associated with High Grade Prostate Cancer on Radical Prostatectomy Specimens

Directory of Open Access Journals (Sweden)

Michael Andre Liss

2015-02-01

Full Text Available Objectives: We evaluate a novel magnetic resonance imaging (MRI technique to improve detection of aggressive prostate cancer. Methods: We performed a retrospective analysis of presurgical prostate MRI scans using an advanced diffusion weighted imaging technique called Restriction Spectrum Imaging (RSI, which can be presented as a normalized z-score statistic (RSI z-score. Scans were acquired prior to radical prostatectomy. Prostatectomy specimens were processed using whole mount sectioning and regions of interest (ROIs were drawn around individual prostate cancer (PCa tumors. Corresponding ROIs were drawn on the MRI imaging and paired with ROIs in regions with no pathology. RSI z-score and conventional apparent diffusion coefficient (ADC values were recorded for each ROI. Paired t-test, ANOVA and logistic regression analyses were performed.Results: We evaluated 28 patients with 64 regions of interest (28 benign and 36 PCa. The mean difference in RSI z-score (PCa ROI – Benign ROI was 2.17 (SE = 0.11; p <0.001 and in ADC was 551 mm2/sec (SE = 80 mm2/sec; paired t-test, p <0.001. The differences in the means among all groups (benign, primary Gleason 3 and primary Gleason 4 was significant for both RSI z-score (F3,64 = 97.7, p <0.001 and ADC (F3,64 = 13.9, p <0.001. A t-test was performed on only PCa tumor ROIs (n=36 to determine prostate cancer aggressiveness (Gleason 3 vs. Gleason 4 revealing that RSI z-score was still significant (p = 0.03, whereas, ADC values were no longer significant (p = 0.08. In multivariable analysis adjusting for age and race, RSI z-score was associated with PCa aggressiveness (OR 10.3, 95%CI: 1.4-78.0, p=0.02 while ADC trended to significance (p=0.07. Conclusions: The RSI derived normalized cellularity index (RSI z-score is associated with aggressive prostate cancer as determined by pathologic Gleason scores. Further utilization of RSI techniques may serve to enhance standardized reporting systems.

Optimal Finite-Thrust Trans-earth Injection (TEI) Maneuvers for a Low Lunar Orbit (LLO) Earth Return Mission

Science.gov (United States)

2010-12-01

1997) A commonly used coordinate system in astrodynamics is called the Geocentric Equatorial Coordinate System (IJK) which is a non-rotating system...final TEI burn had a spacing range of approximately 0.4 to 0.8 minutes between them. The approach therefore was to examine the singular arc by

CHARACTERIZING LANDSCAPE SPATIAL HETEROGENEITY USING SEMIVARIOGRAM PARAMETERS DERIVED FROM NDVI IMAGES

Directory of Open Access Journals (Sweden)

Eduarda Martiniano de Oliveira Silveira

2017-12-01

Full Text Available Assuming a relationship between landscape heterogeneity and measures of spatial dependence by using remotely sensed data, the aim of this work was to evaluate the potential of semivariogram parameters, derived from satellite images with different spatial resolutions, to characterize landscape spatial heterogeneity of forested and human modified areas. The NDVI (Normalized Difference Vegetation Index was generated in an area of Brazilian amazon tropical forest (1,000 km².We selected samples (1 x 1 km from forested and human modified areas distributed throughout the study area, to generate the semivariogram and extract the sill (σ²-overall spatial variability of the surface property and range (φ-the length scale of the spatial structures of objects parameters. The analysis revealed that image spatial resolution influenced the sill and range parameters. The average sill and range values increase from forested to human modified areas and the greatest between-class variation was found for LANDSAT 8 imagery, indicating that this image spatial resolution is the most appropriate for deriving sill and range parameters with the intention of describing landscape spatial heterogeneity. By combining remote sensing and geostatistical techniques, we have shown that the sill and range parameters of semivariograms derived from NDVI images are a simple indicator of landscape heterogeneity and can be used to provide landscape heterogeneity maps to enable researchers to design appropriate sampling regimes. In the future, more applications combining remote sensing and geostatistical features should be further investigated and developed, such as change detection and image classification using object-based image analysis (OBIA approaches.

Process' standardization and change management in higher education. The case of TEI of Athens

Science.gov (United States)

Chalaris, Ioannis; Chalaris, Manolis; Gritzalis, Stefanos; Belsis, Petros

2015-02-01

The establishment of mature operational procedures and the effort of standardizing and certifying these procedures is a particularly arduous and demanding task which requires strong commitment from management to the existing objectives, administrative stability and continuity, availability of resources, an adequate implementation team with support from all stakeholders and of course great tolerance until tangible results of the investment are shown. Ensuring these conditions, particularly in times of economic crisis, is an extremely difficult task for large organizations such as TEI of Athens where there is heterogeneity in personnel and changes in the administrative hierarchy arise plethora of additional difficulties and require an effective change management. In this work we depict the path of standardization and certification of administrative functions of TEI of Athens, with emphasis on difficulties encountered and how to address them and in particular issues of change management and the culture related to this effort. The requirement for infrastructure needed to be maintained in processes and tools process & strategic management is embodied, in order to evolve mechanisms for continuous improvement processes and storage / recovery of the resulting knowledge. The work concludes with a general design of a road map of internal audit and continuous improvement processes for a large institution of higher education.

Region-Based Color Image Indexing and Retrieval

DEFF Research Database (Denmark)

Kompatsiaris, Ioannis; Triantafyllou, Evangelia; Strintzis, Michael G.

2001-01-01

In this paper a region-based color image indexing and retrieval algorithm is presented. As a basis for the indexing, a novel K-Means segmentation algorithm is used, modified so as to take into account the coherence of the regions. A new color distance is also defined for this algorithm. Based on ....... Experimental results demonstrate the performance of the algorithm. The development of an intelligent image content-based search engine for the World Wide Web is also presented, as a direct application of the presented algorithm....

Migratory herbivorous waterfowl track satellite-derived green wave index.

Directory of Open Access Journals (Sweden)

Mitra Shariatinajafabadi

Full Text Available Many migrating herbivores rely on plant biomass to fuel their life cycles and have adapted to following changes in plant quality through time. The green wave hypothesis predicts that herbivorous waterfowl will follow the wave of food availability and quality during their spring migration. However, testing this hypothesis is hampered by the large geographical range these birds cover. The satellite-derived normalized difference vegetation index (NDVI time series is an ideal proxy indicator for the development of plant biomass and quality across a broad spatial area. A derived index, the green wave index (GWI, has been successfully used to link altitudinal and latitudinal migration of mammals to spatio-temporal variations in food quality and quantity. To date, this index has not been used to test the green wave hypothesis for individual avian herbivores. Here, we use the satellite-derived GWI to examine the green wave hypothesis with respect to GPS-tracked individual barnacle geese from three flyway populations (Russian n = 12, Svalbard n = 8, and Greenland n = 7. Data were collected over three years (2008-2010. Our results showed that the Russian and Svalbard barnacle geese followed the middle stage of the green wave (GWI 40-60%, while the Greenland geese followed an earlier stage (GWI 20-40%. Despite these differences among geese populations, the phase of vegetation greenness encountered by the GPS-tracked geese was close to the 50% GWI (i.e. the assumed date of peak nitrogen concentration, thereby implying that barnacle geese track high quality food during their spring migration. To our knowledge, this is the first time that the migration of individual avian herbivores has been successfully studied with respect to vegetation phenology using the satellite-derived GWI. Our results offer further support for the green wave hypothesis applying to long-distance migrants on a larger scale.

Constituintes voláteis de cafés "gourmet" e mole do cerrado do triângulo mineiro em função da torra

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Nascimento Evandro Afonso do

2003-01-01

Full Text Available Neste trabalho foi estudada a variação da composição dos voláteis de dois cafés "gourmet" e de um café mole em função do grau de torrefação. Os cafés provenientes de Araguari, cerrado do Triângulo Mineiro, foram submetidos à torra americana (grãos marrons claros, média (grãos marrons e forte (grãos pretos e, em seguida, moídos e submetidos a uma destilação por arraste de vapor em contra-corrente com diclorometano. A análise de cromatografia gasosa acoplada à espectrometria de massas (CG-EM dos constituintes voláteis mostrou que piridina, pirazina e derivados, furfural e derivados são os principais constituintes voláteis dos cafés analisados. Mostrou ainda que não é possível diferenciar os três tipos de café pelos compostos dominantes (concentração acima de 1% no aroma. Foi observado também que a torra afeta sensivelmente os resultados, sendo que a torra americana, usada normalmente na prova da xícara para classificação sensorial de cafés, produz alguns voláteis de forte impacto no aroma que não aparecem na torra média nem na forte, além de apresentar concentrações dos componentes mais comuns muito diferentes daquelas observadas nas outras duas torras.

Visualization index for image-enabled medical records

Science.gov (United States)

Dong, Wenjie; Zheng, Weilin; Sun, Jianyong; Zhang, Jianguo

2011-03-01

With the widely use of healthcare information technology in hospitals, the patients' medical records are more and more complex. To transform the text- or image-based medical information into easily understandable and acceptable form for human, we designed and developed an innovation indexing method which can be used to assign an anatomical 3D structure object to every patient visually to store indexes of the patients' basic information, historical examined image information and RIS report information. When a doctor wants to review patient historical records, he or she can first load the anatomical structure object and the view the 3D index of this object using a digital human model tool kit. This prototype system helps doctors to easily and visually obtain the complete historical healthcare status of patients, including large amounts of medical data, and quickly locate detailed information, including both reports and images, from medical information systems. In this way, doctors can save time that may be better used to understand information, obtain a more comprehensive understanding of their patients' situations, and provide better healthcare services to patients.

Adaptive responses of cardiac function to fetal postural change as gestational age increases

Science.gov (United States)

Kim, Woo Jin; Choi, Hye Jin; Yang, Sun Young; Koo, Boo Hae; Ahn, Ki Hoon; Hong, Soon Cheol; Oh, Min-Jeong; Kim, Hai-Joong

2016-01-01

Objective The cardiovascular system maintains homeostasis through a series of adaptive responses to physiological requirements. However, little is known about the adaptation of fetal cardiac function to gravity, according to gestational age. In the present study, we aimed to evaluate the adaptive responses of cardiac function to postural changes, using Tei index measurements. Methods Fetal echocardiography and Doppler examination were performed on 114 women with vertex singleton pregnancies at 19 to 40 weeks' gestation. Participants were placed in an upright seated position, and the Tei index for fetal left ventricular cardiac function was measured. The women were then moved into a supine position and the Tei index was re-measured. Results The mean Tei index when measured in an upright seated position was significantly lower than that measured in a supine positioning for all fetuses (0.528±0.103 vs. 0.555±0.106, P=0.014, respectively). This difference was also noted in fetuses with a gestational age of 28–40 weeks (0.539±0.107 vs. 0.574±0.102, P=0.011, respectively). However, there was no difference in the Tei index between an upright seated and a supine position among fetuses with a gestational age of Postural changes from an upright seated to a supine position result in an increased Tei index after a gestational age of 28 weeks. This appears to reflect maturation in the adaptive responses of the fetal cardiovascular system to postural changes. PMID:27896244

Derivation and validation of a composite index of severity in chronic obstructive pulmonary disease: the DOSE Index.

Science.gov (United States)

Jones, Rupert C; Donaldson, Gavin C; Chavannes, Niels H; Kida, Kozui; Dickson-Spillmann, Maria; Harding, Samantha; Wedzicha, Jadwiga A; Price, David; Hyland, Michael E

2009-12-15

Chronic obstructive pulmonary disease (COPD) is increasingly recognized as a multicomponent disease with systemic consequences and effects on quality of life. Single measures such as lung function provide a limited reflection of how the disease affects patients. Composite measures have the potential to account for many of the facets of COPD. To derive and validate a multicomponent assessment tool of COPD severity that is applicable to all patients and health care settings. The index was derived using data from 375 patients with COPD in primary care. Regression analysis led to a model explaining 48% of the variance in health status as measured by the Clinical COPD Questionnaire with four components: dyspnea (D), airflow obstruction (O), smoking status (S), and exacerbation frequency (E). The DOSE Index was validated in cross-sectional and longitudinal samples in various health care settings in Holland, Japan, and the United Kingdom. The DOSE Index correlated with health status in all data sets. A high DOSE Index score (> or = 4) was associated with a greater risk of hospital admission (odds ratio, 8.3 [4.1-17]) or respiratory failure (odds ratio, 7.8 [3.4-18.3]). The index predicted exacerbations in the subsequent year (P Index is a simple, valid tool for assessing the severity of COPD. The index is related to a range of clinically important outcomes such as health care consumption and predicts future events.

Interference Imaging of Refractive Index Distribution in Thin Samples

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Ivan Turek

2004-01-01

Full Text Available There are three versions of interference imaging of refractive index distribution in thin samples suggested in this contribution. These are based on imaging of interference field created by waves reflected from the front and the back sample surface or imaging of interference field of Michelson or Mach-Zehnder interferometer with the sample put in one of the interferometers arm. The work discusses the advantages and disadvantages of these techniques and presents the results of imaging of refrective index distribution in photorefractive record of a quasi-harmonic optical field in thin LiNbO3 crystal sample.

The Training Evaluation Inventory (TEI)--Evaluation of Training Design and Measurement of Training Outcomes for Predicting Training Success

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Ritzmann, Sandrina; Hagemann, Vera; Kluge, Annette

2014-01-01

Training evaluation in research and organisational contexts is vital to ensure informed decisions regarding the value of training. The present study describes the development of a valid and reliable training evaluation inventory (TEI), as it does not exist so far. The objectives were a) to construct an instrument that is theoretically and…

Camera derived vegetation greenness index as proxy for gross primary production in a low Arctic wetland area

DEFF Research Database (Denmark)

Westergaard-Nielsen, Andreas; Lund, Magnus; Hansen, Birger Ulf

2013-01-01

vegetation index (NDVI) product derived from the WorldView-2 satellite. An object-based classification based on a bi-temporal image composite was used to classify the study area into heath, copse, fen, and bedrock. Temporal evolution of vegetation greenness was evaluated and modeled with double sigmoid...... and GPP (R-2 = 0.85, p remote Arctic regions....... (C) 2013 International Society for Photogrammetry and Remote Sensing, Inc. (ISPRS) Published by Elsevier B.V. All rights reserved....

Indexicality or Technological Intermediate? Moving Image Representation, Materiality, and the Real

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Verdon James

2016-09-01

Full Text Available Drawing on the application of C. S. Peirce’s notion of indexicality, this paper argues that iterative imaging technologies modulate the manner in which moving images represent reality and determine how they are traced back to that referent. Rather than subscribing to the canonical divergence between analogue and digital technologies, the paper argues that current moving image theories do not sufficiently acknowledge the granularity of technology when describing indexical relationships between moving images and the reality they represent. Despite a shared use of analogue technologies, film’s technique of fixing a full frame of movement to a momentarily static strip of light-sensitive celluloid or Mylar is profoundly different from analogue video’s parsing of the image frame to its constituent parts and then recording this signal to continuously moving tape or broadcasting the resulting images. These are particularities of technique and technology, not easily ranked in terms of verisimilitude. The paper concludes that despite a widely accepted indexical analogue/digital divide, the indexical status of analogue video is no different to that of digital video images because both consist of discrete and non-continuous picture elements.

Performance comparison of different graylevel image fusion schemes through a universal image quality index

NARCIS (Netherlands)

Toet, A.; Hogervorst, M.A.

2003-01-01

We applied a recently introduced universal image quality index Q that quantifies the distortion of a processed image relative to its original version, to assess the performance of different graylevel image fusion schemes. The method is as follows. First, we adopt an original test image as the

Focused Ultrasound-Induced Blood-Brain Barrier Opening: Association with Mechanical Index and Cavitation Index Analyzed by Dynamic Contrast-Enhanced Magnetic-Resonance Imaging.

Science.gov (United States)

Chu, Po-Chun; Chai, Wen-Yen; Tsai, Chih-Hung; Kang, Shih-Tsung; Yeh, Chih-Kuang; Liu, Hao-Li

2016-09-15

Focused ultrasound (FUS) with microbubbles can temporally open the blood-brain barrier (BBB), and the cavitation activities of microbubbles play a key role in the BBB-opening process. Previous attempts used contrast-enhanced magnetic resonance imaging (CE-MRI) to correlate the mechanical index (MI) with the scale of BBB-opening, but MI only partially gauged acoustic activities, and CE-MRI did not fully explore correlations of pharmacodynamic/pharmacokinetic behaviors. Recently, the cavitation index (CI) has been derived to serve as an indicator of microbubble-ultrasound stable cavitation, and may also serve as a valid indicator to gauge the level of FUS-induced BBB opening. This study investigates the feasibility of gauging FUS-induced BBB opened level via the two indexes, MI and CI, through dynamic contrast-enhanced (DCE)-MRI analysis as well as passive cavitation detection (PCD) analysis. Pharmacodynamic/pharmacokinetic parameters derived from DCE-MRI were characterized to identify the scale of FUS-induced BBB opening. Our results demonstrated that DCE-MRI can successfully access pharmacodynamic/pharmacokinetic BBB-opened behavior, and was highly correlated both with MI and CI, implying the feasibility in using these two indices to gauge the scale of FUS-induced BBB opening. The proposed finding may facilitate the design toward using focused ultrasound as a safe and reliable noninvasive CNS drug delivery.

A novel biomedical image indexing and retrieval system via deep preference learning.

Science.gov (United States)

Pang, Shuchao; Orgun, Mehmet A; Yu, Zhezhou

2018-05-01

The traditional biomedical image retrieval methods as well as content-based image retrieval (CBIR) methods originally designed for non-biomedical images either only consider using pixel and low-level features to describe an image or use deep features to describe images but still leave a lot of room for improving both accuracy and efficiency. In this work, we propose a new approach, which exploits deep learning technology to extract the high-level and compact features from biomedical images. The deep feature extraction process leverages multiple hidden layers to capture substantial feature structures of high-resolution images and represent them at different levels of abstraction, leading to an improved performance for indexing and retrieval of biomedical images. We exploit the current popular and multi-layered deep neural networks, namely, stacked denoising autoencoders (SDAE) and convolutional neural networks (CNN) to represent the discriminative features of biomedical images by transferring the feature representations and parameters of pre-trained deep neural networks from another domain. Moreover, in order to index all the images for finding the similarly referenced images, we also introduce preference learning technology to train and learn a kind of a preference model for the query image, which can output the similarity ranking list of images from a biomedical image database. To the best of our knowledge, this paper introduces preference learning technology for the first time into biomedical image retrieval. We evaluate the performance of two powerful algorithms based on our proposed system and compare them with those of popular biomedical image indexing approaches and existing regular image retrieval methods with detailed experiments over several well-known public biomedical image databases. Based on different criteria for the evaluation of retrieval performance, experimental results demonstrate that our proposed algorithms outperform the state

Derivative based sensitivity analysis of gamma index

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Biplab Sarkar

2015-01-01

Full Text Available Originally developed as a tool for patient-specific quality assurance in advanced treatment delivery methods to compare between measured and calculated dose distributions, the gamma index (γ concept was later extended to compare between any two dose distributions. It takes into effect both the dose difference (DD and distance-to-agreement (DTA measurements in the comparison. Its strength lies in its capability to give a quantitative value for the analysis, unlike other methods. For every point on the reference curve, if there is at least one point in the evaluated curve that satisfies the pass criteria (e.g., δDD = 1%, δDTA = 1 mm, the point is included in the quantitative score as "pass." Gamma analysis does not account for the gradient of the evaluated curve - it looks at only the minimum gamma value, and if it is <1, then the point passes, no matter what the gradient of evaluated curve is. In this work, an attempt has been made to present a derivative-based method for the identification of dose gradient. A mathematically derived reference profile (RP representing the penumbral region of 6 MV 10 cm × 10 cm field was generated from an error function. A general test profile (GTP was created from this RP by introducing 1 mm distance error and 1% dose error at each point. This was considered as the first of the two evaluated curves. By its nature, this curve is a smooth curve and would satisfy the pass criteria for all points in it. The second evaluated profile was generated as a sawtooth test profile (STTP which again would satisfy the pass criteria for every point on the RP. However, being a sawtooth curve, it is not a smooth one and would be obviously poor when compared with the smooth profile. Considering the smooth GTP as an acceptable profile when it passed the gamma pass criteria (1% DD and 1 mm DTA against the RP, the first and second order derivatives of the DDs (δD', δD" between these two curves were derived and used as the

Impact damage imaging in a curved composite panel with wavenumber index via Riesz transform

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Chang, Huan-Yu; Yuan, Fuh-Gwo

2018-03-01

The barely visible impact damages reduce the strength of composite structures significantly; however, they are difficult to be detected during regular visual inspection. A guided wave based damage imaging condition method is developed and applied on a curved composite panel, which is a part of an aileron from a retired Boeing C-17 Globemaster III. Ultrasonic guided waves are excited by a piezoelectric transducer (PZT) and then captured by a laser Doppler vibrometer (LDV). The wavefield images are constructed by measuring the out-of-plane velocity point by point within interrogation region, and the anomalies at the damage area can be observed with naked eye. The discontinuities of material properties leads to the change of wavenumber while the wave propagating through the damaged area. These differences in wavenumber can be observed by deriving instantaneous wave vector via Riesz transform (RT), and then be shown and highlighted with the proposed imaging condition named wavenumber index (WI). RT can be introduced as a two-dimensional (2-D) generalization of Hilbert transform (HT) to derive instantaneous phases, amplitudes, orientations of a guided-wave field. WI employs the instantaneous wave vector and weighted instantaneous wave energy computed from the instantaneous amplitudes, yielding high sensitivity and sharp damage image with computational efficiency. The BVID of the composite structure becomes therefore "visible" with the developed technique.

Feasibility study and quality assessment of unmanned aircraft system-derived multispectral images

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Chang, Kuo-Jen

2017-04-01

The purpose of study is to explore the precision and the applicability of UAS-derived multispectral images. In this study, the Micro-MCA6 multispectral camera was mounted on quadcopter. The Micro-MCA6 shoot images synchronized of each single band. By means of geotagged images and control points, the orthomosaic images of each single band generated firstly by 14cm resolution. The multispectral image was merged complete with 6 bands. In order to improve the spatial resolution, the 6 band image fused with 9cm resolution image taken from RGB camera. Quality evaluation of the image is verified of the each single band by using control points and check points. The standard deviations of errors are within 1 to 2 pixel resolution of each band. The quality of the multispectral image is compared with 3 cm resolution orthomosaic RGB image gathered from UAV in the same mission, as well. The standard deviations of errors are within 2 to 3 pixel resolution. The result shows that the errors resulting from the blurry and the band dislocation of the objects edge identification. To the end, the normalized difference vegetation index (NDVI) extracted from the image to explore the condition of vegetation and the nature of the environment. This study demonstrates the feasibility and the capability of the high resolution multispectral images.

Fingerprint Image Enhancement Based on Second Directional Derivative of the Digital Image

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Onnia Vesa

2002-01-01

Full Text Available This paper presents a novel approach of fingerprint image enhancement that relies on detecting the fingerprint ridges as image regions where the second directional derivative of the digital image is positive. A facet model is used in order to approximate the derivatives at each image pixel based on the intensity values of pixels located in a certain neighborhood. We note that the size of this neighborhood has a critical role in achieving accurate enhancement results. Using neighborhoods of various sizes, the proposed algorithm determines several candidate binary representations of the input fingerprint pattern. Subsequently, an output binary ridge-map image is created by selecting image zones, from the available binary image candidates, according to a MAP selection rule. Two public domain collections of fingerprint images are used in order to objectively assess the performance of the proposed fingerprint image enhancement approach.

A New ENSO Index Derived from Satellite Measurements of Column Ozone

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Ziemke, J. R.; Chandra, S.; Oman, L. D.; Bhartia, P. K.

2010-01-01

Column Ozone measured in tropical latitudes from Nimbus 7 total ozone mapping spectrometer (TOMS), Earth Probe TOMS, solar backscatter ultraviolet (SBUV), and Aura ozone monitoring instrument (OMI) are used to derive an El Nino-Southern Oscillation (ENSO) index. This index, which covers a time period from 1979 to the present, is defined as the Ozone ENSO Index (OEI) and is the first developed from atmospheric trace gas measurements. The OEI is constructed by first averaging monthly mean column ozone over two broad regions in the western and eastern Pacific and then taking their difference. This differencing yields a self-calibrating ENSO index which is independent of individual instrument calibration offsets and drifts in measurements over the long record. The combined Aura OMI and MLS ozone data confirm that zonal variability in total column ozone in the tropics caused by ENSO events lies almost entirely in the troposphere. As a result, the OEI can be derived directly from total column ozone instead of tropospheric column ozone. For clear-sky ozone measurements a +1K change in Nino 3.4 index corresponds to +2.9 Dobson Unit (DU) change in the OEI, while a +1 hPa change in SOI coincides with a -1.7DU change in the OEI. For ozone measurements under all cloud conditions these numbers are +2.4DU and -1.4 DU, respectively. As an ENSO index based upon ozone, it is potentially useful in evaluating climate models predicting long term changes in ozone and other trace gases.

Análise qualitativa de compostos voláteis do headspace de carne cozida de ovinos e caprinos

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Jossiê Zamperetti Donadel

2013-11-01

Full Text Available Este estudo teve como objetivo caracterizar qualitativamente os compostos voláteis (CV do headspace de diferentes músculos de carne cozida de ovinos e caprinos da região do Alto Camaquã, Rio Grande do Sul - Brasil. Os CV do headspace dos músculos cozidos, L. dorsi e V. lateralis de cinco ovinos machos (idade de 6 meses e cinco cabritos machos castrados (idade de 8-9 meses foram analisados pela técnica de microextração em fase sólida (HS-SPME e cromatógrafo a gás acoplado a espectrômetro de massas (GC/MS. Foram encontrados 73 compostos voláteis, dentre eles aldeídos, cetonas e compostos sulfurados, característicos de carne processada termicamente. A partir da fração volátil, foi possível encontrar marcadores que discriminassem as espécies animais estudadas, caracterizando os caprinos por apresentarem, entre outros compostos, terpenos (β-pineno, α-gurjuneno, α-muuroleno, ausentes em ovinos. Alguns compostos discriminaram V. lateralis e L. dorsi de ovinos, como álcool isopropílico, α-pineno, o-xileno, porém não foi possível obter uma diferenciação entre os músculos de caprinos.

CMOS image sensor-based immunodetection by refractive-index change.

Science.gov (United States)

Devadhasan, Jasmine P; Kim, Sanghyo

2012-01-01

A complementary metal oxide semiconductor (CMOS) image sensor is an intriguing technology for the development of a novel biosensor. Indeed, the CMOS image sensor mechanism concerning the detection of the antigen-antibody (Ag-Ab) interaction at the nanoscale has been ambiguous so far. To understand the mechanism, more extensive research has been necessary to achieve point-of-care diagnostic devices. This research has demonstrated a CMOS image sensor-based analysis of cardiovascular disease markers, such as C-reactive protein (CRP) and troponin I, Ag-Ab interactions on indium nanoparticle (InNP) substrates by simple photon count variation. The developed sensor is feasible to detect proteins even at a fg/mL concentration under ordinary room light. Possible mechanisms, such as dielectric constant and refractive-index changes, have been studied and proposed. A dramatic change in the refractive index after protein adsorption on an InNP substrate was observed to be a predominant factor involved in CMOS image sensor-based immunoassay.

Three-dimensional display and measurement of cardiac dynamic indexes from MR images

International Nuclear Information System (INIS)

Kono, M.; Matsuo, M.; Yamasaki, K.; Banno, T.; Toriwaki, J.; Yokoi, S.; Oshita, H.

1986-01-01

The cardiac dynamic index, to which such variables as cardiac output, ejection fraction, and wall motion contribute, is routinely determined using various modalities such as angiography, radionuclide imaging, US, and x-ray CT. Each of these modalities, however, has some disadvantages in regard to evaluating the cardiac dynamic index. The authors have obtained precise multidirectional projection images of the heart by means of computer graphics and reformatted data of cardiac MR images obtained with cardiac gating. The contiguous coronal MR images of the heart are made at an interimage distance of 5 mm. In each section, five or six cardiac images can be obtained, depending on the systolic or diastolic phase. These images are stored in a computer, and a three-dimensional display of the heart with biocular observation and with multiplex holograms is made possible with computer graphics. Three-dimensional measurement of the cardiac index is now being attempted, including cardiac output, ejection fraction, and wall motion

Application of a chlorophyll index derived from satellite data to ...

African Journals Online (AJOL)

Application of a chlorophyll index derived from satellite data to investigate the variability of phytoplankton in the Benguela ecosystem. H Demarcq, R Barlow, L Hutchings. Abstract. No Abstract. African Journal of Marine Science Vol.29(2) 2007: pp. 271-282. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD ...

Multiband super-resolution imaging of graded-index photonic crystal flat lens

Science.gov (United States)

Xie, Jianlan; Wang, Junzhong; Ge, Rui; Yan, Bei; Liu, Exian; Tan, Wei; Liu, Jianjun

2018-05-01

Multiband super-resolution imaging of point source is achieved by a graded-index photonic crystal flat lens. With the calculations of six bands in common photonic crystal (CPC) constructed with scatterers of different refractive indices, it can be found that the super-resolution imaging of point source can be realized by different physical mechanisms in three different bands. In the first band, the imaging of point source is based on far-field condition of spherical wave while in the second band, it is based on the negative effective refractive index and exhibiting higher imaging quality than that of the CPC. However, in the fifth band, the imaging of point source is mainly based on negative refraction of anisotropic equi-frequency surfaces. The novel method of employing different physical mechanisms to achieve multiband super-resolution imaging of point source is highly meaningful for the field of imaging.

Self-imaging of partially coherent light in graded-index media.

Science.gov (United States)

Ponomarenko, Sergey A

2015-02-15

We demonstrate that partially coherent light beams of arbitrary intensity and spectral degree of coherence profiles can self-image in linear graded-index media. The results can be applicable to imaging with noisy spatial or temporal light sources.

Images en mouvement stockage, repérage, indexation

CERN Document Server

Turner, James

1998-01-01

L'avènement puis la fusion des nouveaux modes de communication que sont l'informatique, les télécommunications et l'audiovisuel ont mis à la portée de tous une grande quantité d'images fixes et en mouvement dont la conservation et le repérage risquent de prendre des proportions démesurées. Le présent ouvrage veut offrir aux responsables de collection des repères pour aborder la problématique de l'indexation des images et faciliter l'accès des usagers à ces images.

OTIMIZAÇÃO DA ETAPA DE ISOLAMENTO DOS COMPOSTOS VOLÁTEIS DE MEL PARA ANÁLISE POR CROMATOGRAFIA GASOSA

Directory of Open Access Journals (Sweden)

Deborah H. M. BASTOS

2009-07-01

Full Text Available

O presente trabalho teve por objetivo desenvolver e detalhar uma metodologia de isolamento de compostos voláteis de mel de laranja, utilizando técnica de concentração do headspace e processo de otimização do tempo de captura e do solvente utilizado por meio de métodos sensoriais e instrumentais. Os voláteis foram capturados em polimero Porapak-Q, com tempos de captura variando entre 2 e 4 horas, utilizando-se acetona e hexano para sua desorção. Uma equipe sensorial treinada, composta por oito julgadores selecionados com base em poder discriminativo, repetibilidade e consenso nos julgamentos, avaliou a intensidade de aroma característico de mel em cada um dos isolados obtidos. Realizou-se análise cromatográfica em cada uma das fiações isoladas e o número de picos obtidos foi computado. Análise de variância univariada (ANOVA dos dados sensoriais indicou a acetona como o melhor solvente para eluição dos compostos capturados no polímero poroso e o tempo de captura de 3 horas suficiente para se obter um isolado, apresentando intensidade moderada de aroma característico de mel. Os dados instrumentais confirmaram os resultados obtidos pela análise sensorial dos isolados.

The development of a magnetic resonance imaging index for fistulising Crohn's disease

NARCIS (Netherlands)

Samaan, M. A.; Puylaert, C. A. J.; Levesque, B. G.; Zou, G. Y.; Stitt, L.; Taylor, S. A.; Shackelton, L. M.; Vandervoort, M. K.; Khanna, R.; Santillan, C.; Rimola, J.; Hindryckx, P.; Nio, C. Y.; Sandborn, W. J.; D'Haens, G.; Feagan, B. G.; Jairath, V.; Stoker, J.

2017-01-01

Magnetic resonance imaging (MRI) is the gold standard for assessment of perianal fistulising Crohn's disease (CD). The Van Assche index is the most commonly used MRI fistula index. To assess the reliability of the Van Assche index, and to modify the instrument to improve reliability and create a

Evaluation of the data of vegetable covering using fraction images and multitemporal vegetation index, derived of orbital data of moderate resolution of the sensor MODIS

International Nuclear Information System (INIS)

Murillo Mejia, Mario Humberto

2006-01-01

The objective was to evaluate the data obtained by sensor MODIS onboard the EOS terra satellite land cover units. The study area is the republic of Colombia in South America. The methodology consisted of analyzing the multitemporal (vegetation, soil and shade-water) fraction images and vegetation indices (NDVI) apply the lineal spectral mixture model to products derived from derived images by sensor MODIS data obtained in years 2001 and 2003. The mosaics of the original and the transformed vegetation (soil and shade-water) bands were generated for the whole study area using SPRING 4. 0 software, developed by INPE then these mosaics were segmented, classified, mapped, and edited to obtain a moderate resolution land cover map. The results derived from MODIS analysis were compared with Landsat ETM+ data acquire for a single test site. The results of the project showed the usefulness of MODIS images for large-scale land cover mapping and monitoring studies

Annotation of toponyms in TEI digital literary editions and linking to the web of data

Directory of Open Access Journals (Sweden)

Frontini, Francesca

2016-07-01

Full Text Available This paper aims to discuss the challenges and benefits of the annotation of place names in literary texts and literary criticism. We shall first highlight the problems of encoding spatial information in digital editions using the TEI format by means of two manual annotation experiments and the discussion of various cases. This will lead to the question of how to use existing semantic web resources to complement and enrich toponym mark-up, in particular to provide mentions with precise georeferencing. Finally the automatic annotation of a large corpus will show the potential of visualizing places from texts, by illustrating an analysis of the evolution of literary life from the spatial and geographical point of view.

Frugivoria e dispersão de sementes pelo lagarto teiú Tupinambis merianae (Reptilia: Teiidae Frugivory and seed dispersal by the tegu lizard Tupinambis merianae Reptilia: Teiidae

Directory of Open Access Journals (Sweden)

Everaldo Rodrigo de Castro

2004-01-01

Full Text Available Os lagartos teiús possuem uma dieta generalista, podendo agir como importantes dispersores de sementes em florestas semidecíduas do sudeste do Brasil. Foram estudadas a frugivoria e a dispersão de sementes de lagartos teiús usando animais em cativeiro, através da oferta de frutos de uma floresta semidecídua. Frutos de trinta espécies vegetais foram oferecidos aos lagartos em cativeiro, com diâmetro variando de 0,81 a 10,0 cm. Não foram encontradas diferenças estatísticas na germinação entre as sementes que passaram pelo trato digestivo do lagarto e as controle de Eugenia uniflora (chi²= 0.69, P>0.50, Genipa americana (chi²= 6.4, P>0.975, Cereus peruvianus (chi²= 0.018, P>0.10, e Solanum viarum (chi²= 6.23, P>0.975. O tempo de retenção da semente no tubo digestivo do teiú variou de 22 a 23 h para Solanum lycocarpum e 43 a 44 h para Syagrus romanzoffiana. Nossos resultados indicam que o lagarto teiú tem potencial para agir como um importante dispersor de sementes nos trópicos.Tegu lizards have a generalist diet and may play an important role as seed dispersers in semideciduous forests in south-east Brazil. We studied the frugivory and seed dispersal of tegu lizards using captive animals and offering wild fruits from a semideciduous forest. Thirty fruit species were eaten by the lizards in captivity, ranging from 0.81 to 10.0 cm (fruit diameter. Even large fruit adapted to dispersal by large mammals were swallowed (ex. Syagrus oleracea. There were no statistical differences in seed germination between seeds that passed through the lizard gut and the control in Eugenia uniflora (chi2 = 0.69, P>0.50, Genipa americana (chi2 = 6.4, P>0.975, Cereus peruvianus (chi2 = 0.018, P>0.10, and Solanum viarum (chi2 = 6.23, P>0.975. Seed retention time in the tegu gut ranged from 2224 h (Solanum lycocarpum to 4344 h (for Syagrus romanzoffiana. Our results indicate that tegu lizards have a potential to be an important seed dispersers in the

An initial ULF wave index derived from 2 years of Swarm observations

Science.gov (United States)

Papadimitriou, Constantinos; Balasis, Georgios; Daglis, Ioannis A.; Giannakis, Omiros

2018-03-01

The ongoing Swarm satellite mission provides an opportunity for better knowledge of the near-Earth electromagnetic environment. Herein, we use a new methodological approach for the detection and classification of ultra low-frequency (ULF) wave events observed by Swarm based on an existing time-frequency analysis (TFA) tool and utilizing a state-of-the-art high-resolution magnetic field model and Swarm Level 2 products (i.e., field-aligned currents - FACs - and the Ionospheric Bubble Index - IBI). We present maps of the dependence of ULF wave power with magnetic latitude and magnetic local time (MLT) as well as geographic latitude and longitude from the three satellites at their different locations in low-Earth orbit (LEO) for a period spanning 2 years after the constellation's final configuration. We show that the inclusion of the Swarm single-spacecraft FAC product in our analysis eliminates all the wave activity at high altitudes, which is physically unrealistic. Moreover, we derive a Swarm orbit-by-orbit Pc3 wave (20-100 MHz) index for the topside ionosphere and compare its values with the corresponding variations of solar wind variables and geomagnetic activity indices. This is the first attempt, to our knowledge, to derive a ULF wave index from LEO satellite data. The technique can be potentially used to define a new Level 2 product from the mission, the Swarm ULF wave index, which would be suitable for space weather applications.

A climate index derived from satellite measured spectral infrared radiation. Ph.D. Thesis

Science.gov (United States)

Abel, M. D.; Fox, S. K.

1982-01-01

The vertical infrared radiative emitting structure (VIRES) climate index, based on radiative transfer theory and derived from the spectral radiances typically used to retrieve temperature profiles, is introduced. It is assumed that clouds and climate are closely related and a change in one will result in a change in the other. The index is a function of the cloud, temperature, and moisture distributions. It is more accurately retrieved from satellite data than is cloudiness per se. The VIRES index is based upon the shape and relative magnitude of the broadband weighting function of the infrared radiative transfer equation. The broadband weighting curves are retrieved from simulated satellite infrared sounder data (spectral radiances). The retrieval procedure is described and the error error sensitivities of the method investigated. Index measuring options and possible applications of the VIRES index are proposed.

Effect of imaging time on the values of the sacroiliac index

International Nuclear Information System (INIS)

Dodig, D.; Domljan, Z.; Popovic, S.; Simonovic, I.; Zagreb Univ.

1988-01-01

Quantitative scintigraphy of the sacroiliac joints was performed in a group of normal subjects and a group of subjects with unilateral and bilateral sacroiliitis. The aim of the study was to determine whether the time intervals of imaging had any effect on the values of the sacroiliac index. Imaging was performed every 30 min up to 300 min and the indices were calculated at the time intervals mentioned. We found that the values of the sacroiliac index increased in the group of normal subjects until 150 min after the application of the radiopharmaceutical, and that in the group of subjects who had sacroiliitis they increased until 210 min. The results show that the time interval optimal to quantitative sacroiliac joint imaging is at least 3 1/2 h after administration of the radiopharmaceutical. (orig.)

Refractive index sensing using Fluorescence Lifetime Imaging (FLIM)

International Nuclear Information System (INIS)

Jones, Carolyn; Suhling, Klaus

2006-01-01

The fluorescence lifetime is a function of the refractive index of the fluorophore's environment, for example in the case of the biologically important green fluorescent protein (GFP). In order to address the question whether this effect can be exploited to image the local environment of specific proteins in cell biology, we need to determine the distance over which the fluorophore's lifetime is sensitive to the refractive index. To this end, we employ Fluorescence Lifetime Imaging (FLIM) of fluorescein in NaOH buffer at an interface. This approach allows us to map the fluorescence lifetime as a function of distance from a buffer/air and buffer/oil interface. Preliminary data show that the fluorescence lifetime of fluorescein increases near a buffer/air interface and decreases near a buffer/oil interface. The range over which this fluorescence lifetime change occurs is found to be of the order several μm which is consistent with a theoretical model based on the full width at half maximum of the emission spectrum proposed by Toptygin

Image-based reflectance conversion of ASTER and IKONOS ...

African Journals Online (AJOL)

Spectral signatures derived from different image-based models for ASTER and IKONOS were inspected visually as first departure. This was followed by comparison of the total accuracy and Kappa index computed from supervised classification of images that were derived from different image-based atmospheric correction ...

Deep Hashing Based Fusing Index Method for Large-Scale Image Retrieval

Directory of Open Access Journals (Sweden)

Lijuan Duan

2017-01-01

Full Text Available Hashing has been widely deployed to perform the Approximate Nearest Neighbor (ANN search for the large-scale image retrieval to solve the problem of storage and retrieval efficiency. Recently, deep hashing methods have been proposed to perform the simultaneous feature learning and the hash code learning with deep neural networks. Even though deep hashing has shown the better performance than traditional hashing methods with handcrafted features, the learned compact hash code from one deep hashing network may not provide the full representation of an image. In this paper, we propose a novel hashing indexing method, called the Deep Hashing based Fusing Index (DHFI, to generate a more compact hash code which has stronger expression ability and distinction capability. In our method, we train two different architecture’s deep hashing subnetworks and fuse the hash codes generated by the two subnetworks together to unify images. Experiments on two real datasets show that our method can outperform state-of-the-art image retrieval applications.

Entire Functions of Bounded L-Index: Its Zeros and Behavior of Partial Logarithmic Derivatives

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Andriy Bandura

2017-01-01

Full Text Available In this paper, we obtain new sufficient conditions of boundedness of L-index in joint variables for entire function in Cn functions. They give an estimate of maximum modulus of an entire function by its minimum modulus on a skeleton in a polydisc and describe the behavior of all partial logarithmic derivatives and the distribution of zeros. In some sense, the obtained results are new for entire functions of bounded index and l-index in C too. They generalize known results of Fricke, Sheremeta, and Kuzyk.

Evaluation of the effects of diuron and its derivatives on Lemna gibba using a fluorescence toxicity index.

Science.gov (United States)

Dewez, David; Marchand, Mathieu; Eullaffroy, Philippe; Popovic, Radovan

2002-10-01

The herbicide diuron (DCMU) [3-(3,4-dichlorophenyl)-1,1-dimethylurea] is largely used in agricultural practices which contribute to water pollution in large areas. Its degradation induced by light or microbial activity is known to be a slow process, and may result in the accumulation of DCMU derivatives in the environment. In this report we used the yield of PSII variable fluorescence of Lemna gibba affected by the DCMU derivatives DCPMU [1-(3,4-dichlorophenyl)-3-methylurea], DCPU [1-(3,4-dichlorophenyl)urea], and DCA [3,4-dichloroaniline] to calculate the fluorescence toxicity index. We found the fluorescence toxicity index to be a useful parameter to evaluate the inhibitory effect on PSII electron transport in L. gibba exposed to DCMU and its derivatives. The variations observed for the inhibitory effect between DCMU and its derivatives seem to be caused by the modification of the dimethylurea group within the DCMU molecule. The fluorescence toxicity index demonstrated a strong quantitative dependency between the inhibitory effect of PSII electron transport and pollutant concentrations. We propose the fluorescence toxicity index to be a useful tool for future bioassays in evaluating the quality of water polluted with herbicides that induce an inhibition to PSII photochemistry. Copyright 2002 Wiley Periodicals, Inc.

Prediction of clamp-derived insulin sensitivity from the oral glucose insulin sensitivity index

DEFF Research Database (Denmark)

Tura, Andrea; Chemello, Gaetano; Szendroedi, Julia

2018-01-01

that underwent both a clamp and an OGTT or meal test, thereby allowing calculation of both the M value and OGIS. The population was divided into a training and a validation cohort (n = 359 and n = 154, respectively). After a stepwise selection approach, the best model for M value prediction was applied......AIMS/HYPOTHESIS: The euglycaemic-hyperinsulinaemic clamp is the gold-standard method for measuring insulin sensitivity, but is less suitable for large clinical trials. Thus, several indices have been developed for evaluating insulin sensitivity from the oral glucose tolerance test (OGTT). However......, most of them yield values different from those obtained by the clamp method. The aim of this study was to develop a new index to predict clamp-derived insulin sensitivity (M value) from the OGTT-derived oral glucose insulin sensitivity index (OGIS). METHODS: We analysed datasets of people...

Integrated NDVI images for Niger 1986-1987. [Normalized Difference Vegetation Index

Science.gov (United States)

Harrington, John A., Jr.; Wylie, Bruce K.; Tucker, Compton J.

1988-01-01

Two NOAA AVHRR images are presented which provide a comparison of the geographic distribution of an integration of the normalized difference vegetation index (NDVI) for the Sahel zone in Niger for the growing seasons of 1986 and 1987. The production of the images and the application of the images for resource management are discussed. Daily large area coverage with a spatial resolution of 1.1 km at nadir were transformed to the NDVI and geographically registered to produce the images.

On the derivation of vector radiative transfer equation for polarized radiative transport in graded index media

International Nuclear Information System (INIS)

Zhao, J.M.; Tan, J.Y.; Liu, L.H.

2012-01-01

Light transport in graded index media follows a curved trajectory determined by Fermat's principle. Besides the effect of variation of the refractive index on the transport of radiative intensity, the curved ray trajectory will induce geometrical effects on the transport of polarization ellipse. This paper presents a complete derivation of vector radiative transfer equation for polarized radiation transport in absorption, emission and scattering graded index media. The derivation is based on the analysis of the conserved quantities for polarized light transport along curved trajectory and a novel approach. The obtained transfer equation can be considered as a generalization of the classic vector radiative transfer equation that is only valid for uniform refractive index media. Several variant forms of the transport equation are also presented, which include the form for Stokes parameters defined with a fixed reference and the Eulerian forms in the ray coordinate and in several common orthogonal coordinate systems.

Derivation of the Radioactivity Index for Consumer Goods Containing NORM

Energy Technology Data Exchange (ETDEWEB)

Jang, Mee; Chung, Kun Ho; Ji, Young Yong; Kim, Chang Jong; Kang, Mun Ja [KAERI, Daejeon (Korea, Republic of)

2016-05-15

Some consumer goods to promote health such as anion bracelets, necklace and mats contain naturally occurring radioactive material (NORM). Some of them can cause problems because of high radioactivity. In the regulations, there is an annual effective dose limit of 1mSv for products, but the activity concentration limits and radioactivity index for products is not established yet. Although there are few researches for consumer goods containing NORM in foreign countries, in Japan, for the consumer goods. To regulate the NORM in consumer goods, it is necessary to derive activity concentration limits corresponding to the annual limits of 1mSv. In this research, we calculated the activity concentration limits according to the usage quantities of consumer goods. Using these results, it is possible to suggest several radioactivity indexes to apply to a lot of consumer goods.

Derivation of the Radioactivity Index for Consumer Goods Containing NORM

International Nuclear Information System (INIS)

Jang, Mee; Chung, Kun Ho; Ji, Young Yong; Kim, Chang Jong; Kang, Mun Ja

2016-01-01

Some consumer goods to promote health such as anion bracelets, necklace and mats contain naturally occurring radioactive material (NORM). Some of them can cause problems because of high radioactivity. In the regulations, there is an annual effective dose limit of 1mSv for products, but the activity concentration limits and radioactivity index for products is not established yet. Although there are few researches for consumer goods containing NORM in foreign countries, in Japan, for the consumer goods. To regulate the NORM in consumer goods, it is necessary to derive activity concentration limits corresponding to the annual limits of 1mSv. In this research, we calculated the activity concentration limits according to the usage quantities of consumer goods. Using these results, it is possible to suggest several radioactivity indexes to apply to a lot of consumer goods

Application of a Simplified Method for Estimating Perfusion Derived from Diffusion-Weighted MR Imaging in Glioma Grading

Directory of Open Access Journals (Sweden)

Mengqiu Cao

2018-01-01

Full Text Available Purpose: To evaluate the feasibility of a simplified method based on diffusion-weighted imaging (DWI acquired with three b-values to measure tissue perfusion linked to microcirculation, to validate it against from perfusion-related parameters derived from intravoxel incoherent motion (IVIM and dynamic contrast-enhanced (DCE magnetic resonance (MR imaging, and to investigate its utility to differentiate low- from high-grade gliomas.Materials and Methods: The prospective study was approved by the local institutional review board and written informed consent was obtained from all patients. From May 2016 and May 2017, 50 patients confirmed with glioma were assessed with multi-b-value DWI and DCE MR imaging at 3.0 T. Besides conventional apparent diffusion coefficient (ADC0,1000 map, perfusion-related parametric maps for IVIM-derived perfusion fraction (f and pseudodiffusion coefficient (D*, DCE MR imaging-derived pharmacokinetic metrics, including Ktrans, ve and vp, as well as a metric named simplified perfusion fraction (SPF, were generated. Correlation between perfusion-related parameters was analyzed by using the Spearman rank correlation. All imaging parameters were compared between the low-grade (n = 19 and high-grade (n = 31 groups by using the Mann-Whitney U test. The diagnostic performance for tumor grading was evaluated with receiver operating characteristic (ROC analysis.Results: SPF showed strong correlation with IVIM-derived f and D* (ρ = 0.732 and 0.716, respectively; both P < 0.001. Compared with f, SPF was more correlated with DCE MR imaging-derived Ktrans (ρ = 0.607; P < 0.001 and vp (ρ = 0.397; P = 0.004. Among all parameters, SPF achieved the highest accuracy for differentiating low- from high-grade gliomas, with an area under the ROC curve value of 0.942, which was significantly higher than that of ADC0,1000 (P = 0.004. By using SPF as a discriminative index, the diagnostic sensitivity and specificity were 87.1% and 94

Changes in right ventricular function assessed by echocardiography in dog models of mild RV pressure overload.

Science.gov (United States)

Morita, Tomoya; Nakamura, Kensuke; Osuga, Tatsuyuki; Yokoyama, Nozomu; Morishita, Keitaro; Sasaki, Noboru; Ohta, Hiroshi; Takiguchi, Mitsuyoshi

2017-07-01

The assessment of hemodynamic change by echocardiography is clinically useful in patients with pulmonary hypertension. Recently, mild elevation of the mean pulmonary arterial pressure (PAP) has been shown to be associated with increased mortality. However, changes in the echocardiographic indices of right ventricular (RV) function are still unknown. The objective of this study was to validate the relationship between echocardiographic indices of RV function and right heart catheterization variables under a mild RV pressure overload condition. Echocardiography and right heart catheterization were performed in dog models of mild RV pressure overload induced by thromboxane A 2 analog (U46619) (n=7). The mean PAP was mildly increased (19.3±1.1 mm Hg), and the cardiac index was decreased. Most echocardiographic indices of RV function were significantly impaired even under a mild RV pressure overload condition. Multivariate analysis revealed that the RV free wall longitudinal strain (RVLS), standard deviation of the time-to-peak longitudinal strain of RV six segments (RV-SD) by speckle-tracking echocardiography, and Tei index were independent echocardiographic predictors of the mean PAP (free wall RVLS, β=-0.60, P<.001; RV-SD, β=0.40, P=.011), pulmonary vascular resistance (free wall RVLS, β=-0.39, P=.020; RV-SD, β=0.47, P=.0086; Tei index, β=0.34, P=.047), and cardiac index (Tei index, β=-0.65, P<.001). Free wall RVLS, RV-SD, and Tei index are useful for assessing the hemodynamic change under a mild RV pressure overload condition. © 2017, Wiley Periodicals, Inc.

A Comparison of Leaf Area Index Maps Derived from Multi-Sensor Optical Data Acquired over Agricultural Areas

Directory of Open Access Journals (Sweden)

Giuseppe Satalino

2010-06-01

Full Text Available The objective of this study is to retrieve and compare Leaf Area Index (LAI maps from temporal series of SPOT, IKONOS and MERIS images acquired, from 2006 to 2008, over an agricultural site in Southern Italy. Results show that the root mean square error (RMSE of LAI derived from MERIS data is approximately 1 m2 m-2, slightly larger than the one obtained by using SPOT and IKONOS data. In addition, LAI retrieved from MERIS data tends to underestimate LAI retrieved from SPOT and IKONOS data, particularly at low LAI values. Nevertheless, the paper gives examples highlighting the strength of MERIS with respect to SPOT and IKONOS data in providing long and dense temporal series of LAI maps suitable to feature the temporal evolution of vegetation growth at regional scale.

Projeções, projetos e projéteis: o nome de 'África' e a subjetivação imperial em \\"Lágrimas Do Sol\\" (2003)

OpenAIRE

Marcelo R. S. Ribeiro

2008-01-01

RIBEIRO, Marcelo Rodrigues Souza. Projeções, projetos e projéteis: o nome de 'África' e a subjetivação imperial em \\"Lágrimas do Sol\\" (2003)\\". In: HAMBURGER, Esther; SOUZA, Gustavo; MENDONÇA, Leandro; AMANCIO, Tunico. (Org.). Estudos de Cinema SOCINE. 1 ed. São Paulo: Annablume; Fapesp; Socine, 2008, v. , p. 199-207.

The percien contribution for an indexal representation of visual images

Directory of Open Access Journals (Sweden)

Virginia Bentes Pinto

2008-04-01

Full Text Available However, even if along history the visual images have gained a great importance as sources of information, one cannot deny that with the newest information and communication technologies (ICT they drew the attention of experts from the most different fields of knowledge, such as arts, biology, astronomy, archeology, history, health, fashion, decoration, public relations, editing, engineering and architecture, among others. Presents some theoretical reflections concerning representation in Peirce’s perspective based on the context of the new approaches used for the treatment of visual images, using as examples the paradigms of the manual, semiautomatic, automatic and mixed index representation. The results of the experiments show that the difficulties found in the construction of an index representation of that document type originate from the complexity inherent in the process of production and reception of the imagetic sign.

Defect Tolerance to Intolerance in the Vacancy-Ordered Double Perovskite Semiconductors Cs ₂ SnI ₆ and Cs ₂ TeI ₆

Energy Technology Data Exchange (ETDEWEB)

Maughan, Annalise E.; Ganose, Alex M.; Bordelon, Mitchell M.; Miller, Elisa M.; Scanlon, David O.; Neilson, James R.

2016-07-13

Vacancy-ordered double perovskites of the general formula, A2BX6, are a family of perovskite derivatives composed of a face-centered lattice of nearly isolated [BX6] units with A-site cations occupying the cuboctahedral voids. Despite the presence of isolated octahedral units, the close-packed iodide lattice provides significant electronic dispersion, such that Cs2SnI6 has recently been explored for applications in photovoltaic devices. To elucidate the structure-property relationships of these materials, we have synthesized the solid solution Cs2Sn1-xTexI6. However, even though tellurium substitution increases electronic dispersion via closer I-I contact distances, the substitution experimentally yields insulating behavior from a significant decrease in carrier concentration and mobility. Density functional calculations of native defects in Cs2SnI6 reveal that iodine vacancies exhibit a low enthalpy of formation and the defect energy level is a shallow donor to the conduction band, rendering the material tolerant to these defect states. The increased covalency of Te-I bonding renders the formation of iodine vacancy states unfavorable, and is responsible for the reduction in conductivity upon Te substitution. Additionally, Cs2TeI6 is intolerant to the formation of these defects, as the defect level occurs deep within the band gap and thus localizes potential mobile charge carriers. In these vacancy-ordered double perovskites, the close-packed lattice of iodine provides significant electronic dispersion, while the interaction of the B- and X-site ions dictates the properties as they pertain to electronic structure and defect tolerance. This simplified perspective -- based on extensive experimental and theoretical analysis -- provides a platform from which to understand structure-property relationships in functional perovskite halides.

Comparing intellectual and graphical complexities of traditional and image-derived landuse maps

Institute of Scientific and Technical Information of China (English)

STEIN; Alfred

2010-01-01

Remotely sensed images have become a powerful source for landuse mapping.So far,no quantitative comparison and evaluation exist on the differences between an image-derived landuse map and a traditional landuse map.The comparison and evaluation may indicate the possibility for the replacement of a traditional landuse map by an image-derived map.Map complexity is widely used to describe cartographic representations and map effectiveness from intellectual aspect and graphical aspect.This paper quantifies intellectual and graphical map complexities to explore the differences between these two kinds of maps.Intellectual complexity concerns the meaning or significations contained on a map.Graphical complexity concerns spatial characteristics of the graphical content on a map.Results show that the high graphical complexity of the image-derived landuse map is not harmonized with its low intellectual complexity.The intention of this paper is to encourage realistic cognition of the accuracy and problems existing in image-derived landuse maps.

Computed tomography of x-ray index of refraction using the diffraction enhanced imaging method

International Nuclear Information System (INIS)

Dilmanian, F.A.; Ren, B.; Wu, X.Y.; Orion, I.; Zhong, Z.; Thomlinson, W.C.; Chapman, L.D.

2000-01-01

Diffraction enhanced imaging (DEI) is a new, synchrotron-based, x-ray radiography method that uses monochromatic, fan-shaped beams, with an analyser crystal positioned between the subject and the detector. The analyser allows the detection of only those x-rays transmitted by the subject that fall into the acceptance angle (central part of the rocking curve) of the monochromator/analyser system. As shown by Chapman et al , in addition to the x-ray attenuation, the method provides information on the out-of-plane angular deviation of x-rays. New images result in which the image contrast depends on the x-ray index of refraction and on the yield of small-angle scattering, respectively. We implemented DEI in the tomography mode at the National Synchrotron Light Source using 22 keV x-rays, and imaged a cylindrical acrylic phantom that included oil-filled, slanted channels. The resulting 'refraction CT image' shows the pure image of the out-of-plane gradient of the x-ray index of refraction. No image artefacts were present, indicating that the CT projection data were a consistent set. The 'refraction CT image' signal is linear with the gradient of the refractive index, and its value is equal to that expected. The method, at the energy used or higher, has the potential for use in clinical radiography and in industry. (author)

Validation of Vegetation Index Time Series from Suomi NPP Visible Infrared Imaging Radiometer Suite Using Tower Radiation Flux Measurements

Science.gov (United States)

Miura, T.; Kato, A.; Wang, J.; Vargas, M.; Lindquist, M.

2015-12-01

Satellite vegetation index (VI) time series data serve as an important means to monitor and characterize seasonal changes of terrestrial vegetation and their interannual variability. It is, therefore, critical to ensure quality of such VI products and one method of validating VI product quality is cross-comparison with in situ flux tower measurements. In this study, we evaluated the quality of VI time series derived from Visible Infrared Imaging Radiometer Suite (VIIRS) onboard the Suomi National Polar-orbiting Partnership (NPP) spacecraft by cross-comparison with in situ radiation flux measurements at select flux tower sites over North America and Europe. VIIRS is a new polar-orbiting satellite sensor series, slated to replace National Oceanic and Atmospheric Administration's Advanced Very High Resolution Radiometer in the afternoon overpass and to continue the highly-calibrated data streams initiated with Moderate Resolution Imaging Spectrometer of National Aeronautics and Space Administration's Earth Observing System. The selected sites covered a wide range of biomes, including croplands, grasslands, evergreen needle forest, woody savanna, and open shrublands. The two VIIRS indices of the Top-of-Atmosphere (TOA) Normalized Difference Vegetation Index (NDVI) and the atmospherically-corrected, Top-of-Canopy (TOC) Enhanced Vegetation Index (EVI) (daily, 375 m spatial resolution) were compared against the TOC NDVI and a two-band version of EVI (EVI2) calculated from tower radiation flux measurements, respectively. VIIRS and Tower VI time series showed comparable seasonal profiles across biomes with statistically significant correlations (> 0.60; p-value 0.95), with mean differences of 2.3 days and 5.0 days for the NDVI and the EVI, respectively. These results indicate that VIIRS VI time series can capture seasonal evolution of vegetated land surface as good as in situ radiometric measurements. Future studies that address biophysical or physiological interpretations

Composição de voláteis e perfil de aroma e sabor de méis de eucalipto e laranja

Directory of Open Access Journals (Sweden)

Bastos Deborah Helena Markowicz

2002-01-01

Full Text Available Neste trabalho foram analisados os compostos voláteis de amostras de mel de eucalipto e laranja colhidos nos estados de São Paulo e de Minas Gerais. O isolamento dos voláteis foi realizado empregando-se uma técnica de ''headspace'' dinâmico, a separação efetuada por cromatografia gasosa de alta resolução e a identificação por espectrometria de massas, Índices de Kovats e padrões, quando disponíveis. Foram identificados no mel de laranja o benzaldeído, o óxido cis de linalol, n-heptanal, 6-metil-5-hepten-2-ona, octanal e fenilacetaldeído, e em mel de eucalipto, o nonanal, 2-heptanona, 2-heptanol, octanol e nonanol. A caracterização sensorial desses méis foi obtida por Análise Descritiva Quantitativa e a aplicação de Análise dos Componentes Principais aos dados revelou que os descritores ''queimado'' e ''sabor residual'' caracterizam o mel de eucalipto, enquanto ''floral'' e ''cera'' caracterizam o mel de laranja. Entre os compostos identificados, o nonanal e o nonanol apresentaram contribuição sensorial importante ao mel de eucalipto, enquanto o fenilacetaldeído e o benzaldeído foram relacionados com os principais descritores do mel de laranja.

Degenerative lumbar spinal stenosis: correlation with Oswestry Disability Index and MR imaging.

Science.gov (United States)

Sirvanci, Mustafa; Bhatia, Mona; Ganiyusufoglu, Kursat Ali; Duran, Cihan; Tezer, Mehmet; Ozturk, Cagatay; Aydogan, Mehmet; Hamzaoglu, Azmi

2008-05-01

Because neither the degree of constriction of the spinal canal considered to be symptomatic for lumbar spinal stenosis nor the relationship between the clinical appearance and the degree of a radiologically verified constriction is clear, a correlation of patient's disability level and radiographic constriction of the lumbar spinal canal is of interest. The aim of this study was to establish a relationship between the degree of radiologically established anatomical stenosis and the severity of self-assessed Oswestry Disability Index in patients undergoing surgery for degenerative lumbar spinal stenosis. Sixty-three consecutive patients with degenerative lumbar spinal stenosis who were scheduled for elective surgery were enrolled in the study. All patients underwent preoperative magnetic resonance imaging and completed a self-assessment Oswestry Disability Index questionnaire. Quantitative image evaluation for lumbar spinal stenosis included the dural sac cross-sectional area, and qualitative evaluation of the lateral recess and foraminal stenosis were also performed. Every patient subsequently answered the national translation of the Oswestry Disability Index questionnaire and the percentage disability was calculated. Statistical analysis of the data was performed to seek a relationship between radiological stenosis and percentage disability recorded by the Oswestry Disability Index. Upon radiological assessment, 27 of the 63 patients evaluated had severe and 33 patients had moderate central dural sac stenosis; 11 had grade 3 and 27 had grade 2 nerve root compromise in the lateral recess; 22 had grade 3 and 37 had grade 2 foraminal stenosis. On the basis of the percentage disability score, of the 63 patients, 10 patients demonstrated mild disability, 13 patients moderate disability, 25 patients severe disability, 12 patients were crippled and three patients were bedridden. Radiologically, eight patients with severe central stenosis and nine patients with moderate

Volatile profile and sensory quality of new varieties of Capsicum chinense pepper Perfil de voláteis e qualidade sensorial de novas variedades de pimentas Capsicum chinense

Directory of Open Access Journals (Sweden)

Deborah dos Santos Garruti

2013-02-01

Full Text Available The objective of this study was to compare the sensory quality and the volatile compound profile of new varieties of Capsicum chinense pepper (CNPH 4080 a strain of'Cumari-do-Pará' and BRS Seriema with a known commercial variety (Biquinho. Volatiles were isolated from the headspace of fresh fruit by SPME and identified by GC-MS. Pickled peppers were produced for sensory evaluation. Aroma descriptors were evaluated by Check-All-That-Apply (CATA method, and the frequency data were submitted to Correspondence Analysis. Flavor acceptance was assessed by hedonic scale and analyzed by ANOVA. BRS Seriema showed the richest volatile profile, with 55 identified compounds, and up to 40% were compounds with sweet aroma notes. CNPH 4080 showed similar volatile profile to that of Biquinho pepper, but it had higher amounts of pepper-like and green-note compounds. The samples did not differ in terms of flavor acceptance, but they showed differences in aroma quality confirming the differences found in the volatile profiles. The C. chinense varieties developed by Embrapa proved to be more aromatic than Biquinho variety, and were well accepted by the judges.O objetivo deste estudo foi comparar a qualidade sensorial e o perfil de compostos voláteis de novas variedades de pimenta Capsicum (CNPH 4080, uma linhagem de cumari-do-pará, e BRS Seriema, com uma variedade comercial (Biquinho. Voláteis foram isolados do headspace dos frutos in natura por SPME e identificados por CG-EM. Conservas das pimentas foram produzidas para a análise sensorial. Descritores do aroma foram avaliados pelo método Check-All-That-Apply (CATA e os dados de frequência submetidos à Análise de Correspondência. A aceitação do sabor das amostras foi analisada por meio de ANOVA. A BRS Seriema apresentou rico perfil de voláteis, com 53 compostos identificados, sendo que cerca de 40% deles são compostos de aroma doce. A CNPH 4080 apresentou perfil semelhante ao da pimenta Biquinho, por

MRI-Derived Cellularity Index as a Potential Noninvasive Imaging Biomarker of Prostate Cancer

Science.gov (United States)

2016-12-01

patients has revealed atypical gelatinous necrosis. We have coined this abnormality bevacizumab-related imaging abnormality (BRIA) and have observed that...neurologic disorders . Radiology 1986;161: 401–7. 25. Merboldt K-D, HanickeW, Frahm J. Self-diffusion NMR imaging using stimulated echoes. J Magn Reson...sensitivity and functional characterization 8 Left peripheral mid gland 3–5 o’clock Bulges the capsule, no gross extraprostatic extension Motion and

Prognostic value and molecular correlates of a CT image-based quantitative pleural contact index in early stage NSCLC

Energy Technology Data Exchange (ETDEWEB)

Lee, Juheon; Cui, Yi; Li, Bailiang; Wu, Jia; Gensheimer, Michael F. [Stanford University School of Medicine, Department of Radiation Oncology, Stanford, CA (United States); Sun, Xiaoli [First Affiliated Hospital of Zhejiang University, Radiotherapy Department, Hangzhou, Zhejiang (China); Li, Dengwang [Stanford University School of Medicine, Department of Radiation Oncology, Stanford, CA (United States); Shandong Normal University, Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Biomedical Sciences, School of Physics and Electronics, Jinan Shi (China); Loo, Billy W.; Li, Ruijiang [Stanford University School of Medicine, Department of Radiation Oncology, Stanford, CA (United States); Stanford University School of Medicine, Stanford Cancer Institute, Stanford, CA (United States); Diehn, Maximilian [Stanford University School of Medicine, Department of Radiation Oncology, Stanford, CA (United States); Stanford University School of Medicine, Stanford Cancer Institute, Stanford, CA (United States); Stanford University School of Medicine, Institute for Stem Cell Biology and Regenerative Medicine, Stanford, CA (United States)

2018-02-15

To evaluate the prognostic value and molecular basis of a CT-derived pleural contact index (PCI) in early stage non-small cell lung cancer (NSCLC). We retrospectively analysed seven NSCLC cohorts. A quantitative PCI was defined on CT as the length of tumour-pleura interface normalised by tumour diameter. We evaluated the prognostic value of PCI in a discovery cohort (n = 117) and tested in an external cohort (n = 88) of stage I NSCLC. Additionally, we identified the molecular correlates and built a gene expression-based surrogate of PCI using another cohort of 89 patients. To further evaluate the prognostic relevance, we used four datasets totalling 775 stage I patients with publically available gene expression data and linked survival information. At a cutoff of 0.8, PCI stratified patients for overall survival in both imaging cohorts (log-rank p = 0.0076, 0.0304). Extracellular matrix (ECM) remodelling was enriched among genes associated with PCI (p = 0.0003). The genomic surrogate of PCI remained an independent predictor of overall survival in the gene expression cohorts (hazard ratio: 1.46, p = 0.0007) adjusting for age, gender, and tumour stage. CT-derived pleural contact index is associated with ECM remodelling and may serve as a noninvasive prognostic marker in early stage NSCLC. (orig.)

Heterogeneity image patch index and its application to consumer video summarization.

Science.gov (United States)

Dang, Chinh T; Radha, Hayder

2014-06-01

Automatic video summarization is indispensable for fast browsing and efficient management of large video libraries. In this paper, we introduce an image feature that we refer to as heterogeneity image patch (HIP) index. The proposed HIP index provides a new entropy-based measure of the heterogeneity of patches within any picture. By evaluating this index for every frame in a video sequence, we generate a HIP curve for that sequence. We exploit the HIP curve in solving two categories of video summarization applications: key frame extraction and dynamic video skimming. Under the key frame extraction frame-work, a set of candidate key frames is selected from abundant video frames based on the HIP curve. Then, a proposed patch-based image dissimilarity measure is used to create affinity matrix of these candidates. Finally, a set of key frames is extracted from the affinity matrix using a min–max based algorithm. Under video skimming, we propose a method to measure the distance between a video and its skimmed representation. The video skimming problem is then mapped into an optimization framework and solved by minimizing a HIP-based distance for a set of extracted excerpts. The HIP framework is pixel-based and does not require semantic information or complex camera motion estimation. Our simulation results are based on experiments performed on consumer videos and are compared with state-of-the-art methods. It is shown that the HIP approach outperforms other leading methods, while maintaining low complexity.

Advective surface velocity in the north west Pacific derived from NOAA AVHRR images

Digital Repository Service at National Institute of Oceanography (India)

Pankajakshan, T.; Akiyama, M.; Okada, Y.; Sugimori, Y.

Using sequential AVHRR images in November 1983, nearsurface advective velocities are derived in the region Kuroshio south of Japan. For deriving the velocities two methods are used. One is the Method of Cross Correlation (MCC), using image pair...

A quantitative index of regional blood flow in canine myocardium derived noninvasively with N-13 ammonia and dynamic positron emission tomography

Energy Technology Data Exchange (ETDEWEB)

Nienaber, C.A.; Ratib, O.; Gambhir, S.S.; Krivokapich, J.; Huang, S.C.; Phelps, M.E.; Schelbert, H.R. (Univ. of California, Los Angeles School of Medicine (USA))

1991-01-01

To derive a quantitative index of regional myocardial blood flow, the arterial input function of the flow tracer N-13 ammonia and the regional myocardial N-13 activity concentrations were noninvasively determined in 29 experiments in eight dogs. N-13 ammonia was administered intravenously and cross-sectional images were acquired dynamically using an ECAT III positron emission tomograph with an effective in-plane resolution of 13.46 mm full-width half-maximum. Time-activity curves were derived from the serial images by assigning regions of interest to the left ventricular myocardium and left ventricular blood pool. Tracer net extractions were estimated from the myocardial time-activity concentrations at various times after tracer injection and the integral of the arterial input function. Myocardial blood flow was altered by intravenous dipyridamole, morphine, propranolol and partial or complete occlusion of the left anterior descending coronary artery, and ranged from 9 to 860 ml/min per 100 g. Estimates of tracer net extractions were most accurate when determined from the myocardial N-13 activity concentrations at 60 s divided by the integral of the arterial input function to that time. These estimates correlated with regional myocardial blood flows determined independently by the microsphere technique by y = x (1 - 0.64(e-114/x); SEE = 22.9; r = 0.94). First pass extraction fractions of N-13 ammonia determined noninvasively with this approach declined with higher flows in a nonlinear fashion and were similar to those determined invasively by direct intracoronary N-13 ammonia injections. The findings indicate that an accurate index of regional myocardial blood flow can be obtained noninvasively by high temporal sampling of arterial and myocardial tracer activity concentrations with positron emission tomography.

Fluorescein Derivatives in Intravital Fluorescence Imaging

Directory of Open Access Journals (Sweden)

Michael S. Roberts

2013-08-01

Full Text Available Intravital fluorescence microscopy enables the direct imaging of fluorophores in vivo and advanced techniques such as fluorescence lifetime imaging (FLIM enable the simultaneous detection of multiple fluorophores. Consequently, it is now possible to record distribution and metabolism of a chemical in vivo and to optimise the delivery of fluorophores in vivo. Recent clinical applications with fluorescein and other intravital fluorescent stains have occurred in neurosurgery, dermatology [including photodynamic therapy (PDT] and endomicroscopy. Potential uses have been identified in periodontal disease, skin graft and cancer surgery. Animal studies have demonstrated that diseased tissue can be specifically stained with fluorophore conjugates. This review focuses on the fluorescein derived fluorophores in common clinical use and provides examples of novel applications from studies in tissue samples.

Automated method to compute Evans index for diagnosis of idiopathic normal pressure hydrocephalus on brain CT images

Science.gov (United States)

Takahashi, Noriyuki; Kinoshita, Toshibumi; Ohmura, Tomomi; Matsuyama, Eri; Toyoshima, Hideto

2017-03-01

The early diagnosis of idiopathic normal pressure hydrocephalus (iNPH) considered as a treatable dementia is important. The iNPH causes enlargement of lateral ventricles (LVs). The degree of the enlargement of the LVs on CT or MR images is evaluated by using a diagnostic imaging criterion, Evans index. Evans index is defined as the ratio of the maximal width of frontal horns (FH) of the LVs to the maximal width of the inner skull (IS). Evans index is the most commonly used parameter for the evaluation of ventricular enlargement. However, manual measurement of Evans index is a time-consuming process. In this study, we present an automated method to compute Evans index on brain CT images. The algorithm of the method consisted of five major steps: standardization of CT data to an atlas, extraction of FH and IS regions, the search for the outmost points of bilateral FH regions, determination of the maximal widths of both the FH and the IS, and calculation of Evans index. The standardization to the atlas was performed by using linear affine transformation and non-linear wrapping techniques. The FH regions were segmented by using a three dimensional region growing technique. This scheme was applied to CT scans from 44 subjects, including 13 iNPH patients. The average difference in Evans index between the proposed method and manual measurement was 0.01 (1.6%), and the correlation coefficient of these data for the Evans index was 0.98. Therefore, this computerized method may have the potential to accurately compute Evans index for the diagnosis of iNPH on CT images.

Radiation risk index for pediatric CT. A patient-derived metric

International Nuclear Information System (INIS)

Samei, Ehsan; Tian, Xiaoyu; Paul Segars, W.; Frush, Donald P.

2017-01-01

There is a benefit in characterizing radiation-induced cancer risk in pediatric chest and abdominopelvic CT: a singular metric that represents the whole-body radiation burden while also accounting for age, gender and organ sensitivity. To compute an index of radiation risk for pediatric chest and abdominopelvic CT. Using a protocol approved by our institutional review board, 42 pediatric patients (age: 0-16 years, weight: 2-80 kg) were modeled into virtual whole-body anatomical models. Organ doses were estimated for clinical chest and abdominopelvic CT examinations of the patients using validated Monte Carlo simulations of two major scanner models. Using age-, size- and gender-specific organ risk coefficients, the values were converted to normalized effective dose (by dose length product) (denoted as the k factor) and a normalized risk index (denoted as the q factor). An analysis was performed to determine how these factors are correlated with patient age and size for both males and females to provide a strategy to better characterize individualized risk. The k factor was found to be exponentially correlated with the average patient diameter. For both genders, the q factor also exhibited an exponential relationship with both the average patient diameter and with patient age. For both factors, the differences between the scanner models were less than 8%. The study defines a whole-body radiation risk index for chest and abdominopelvic CT imaging, that incorporates individual estimated organ dose values, organ radiation sensitivity, patient size, exposure age and patient gender. This indexing metrology enables the assessment and potential improvement of chest and abdominopelvic CT performance through surveillance of practice dose profiles across patients and may afford improved informed communication. (orig.)

Radiation risk index for pediatric CT. A patient-derived metric

Energy Technology Data Exchange (ETDEWEB)

Samei, Ehsan [Duke University Medical Center, Department of Radiology, Carl E. Ravin Advanced Imaging Laboratories, Durham, NC (United States); Duke University Medical Center, Department of Biomedical Engineering, Electrical and Computer Engineering, Durham, NC (United States); Duke University Medical Center, Medical Physics Graduate Program, Durham, NC (United States); Tian, Xiaoyu [Duke University Medical Center, Department of Radiology, Carl E. Ravin Advanced Imaging Laboratories, Durham, NC (United States); Paul Segars, W. [Duke University Medical Center, Department of Radiology, Carl E. Ravin Advanced Imaging Laboratories, Durham, NC (United States); Duke University Medical Center, Medical Physics Graduate Program, Durham, NC (United States); Frush, Donald P. [Duke University Medical Center, Medical Physics Graduate Program, Durham, NC (United States); Duke University Medical Center, Division of Pediatric Radiology, Department of Radiology, Durham, NC (United States)

2017-12-15

There is a benefit in characterizing radiation-induced cancer risk in pediatric chest and abdominopelvic CT: a singular metric that represents the whole-body radiation burden while also accounting for age, gender and organ sensitivity. To compute an index of radiation risk for pediatric chest and abdominopelvic CT. Using a protocol approved by our institutional review board, 42 pediatric patients (age: 0-16 years, weight: 2-80 kg) were modeled into virtual whole-body anatomical models. Organ doses were estimated for clinical chest and abdominopelvic CT examinations of the patients using validated Monte Carlo simulations of two major scanner models. Using age-, size- and gender-specific organ risk coefficients, the values were converted to normalized effective dose (by dose length product) (denoted as the k factor) and a normalized risk index (denoted as the q factor). An analysis was performed to determine how these factors are correlated with patient age and size for both males and females to provide a strategy to better characterize individualized risk. The k factor was found to be exponentially correlated with the average patient diameter. For both genders, the q factor also exhibited an exponential relationship with both the average patient diameter and with patient age. For both factors, the differences between the scanner models were less than 8%. The study defines a whole-body radiation risk index for chest and abdominopelvic CT imaging, that incorporates individual estimated organ dose values, organ radiation sensitivity, patient size, exposure age and patient gender. This indexing metrology enables the assessment and potential improvement of chest and abdominopelvic CT performance through surveillance of practice dose profiles across patients and may afford improved informed communication. (orig.)

Calibrating a hydraulic model using water levels derived from time series high-resolution Radarsat-2 synthetic aperture radar images and elevation data

Science.gov (United States)

Trudel, M.; Desrochers, N.; Leconte, R.

2017-12-01

Knowledge of water extent (WE) and level (WL) of rivers is necessary to calibrate and validate hydraulic models and thus to better simulate and forecast floods. Synthetic aperture radar (SAR) has demonstrated its potential for delineating water bodies, as backscattering of water is much lower than that of other natural surfaces. The ability of SAR to obtain information despite cloud cover makes it an interesting tool for temporal monitoring of water bodies. The delineation of WE combined with a high-resolution digital terrain model (DTM) allows extracting WL. However, most research using SAR data to calibrate hydraulic models has been carried out using one or two images. The objectives of this study is to use WL derived from time series high resolution Radarsat-2 SAR images for the calibration of a 1-D hydraulic model (HEC-RAS). Twenty high-resolution (5 m) Radarsat-2 images were acquired over a 40 km reach of the Athabasca River, in northern Alberta, Canada, between 2012 and 2016, covering both low and high flow regimes. A high-resolution (2m) DTM was generated combining information from LIDAR data and bathymetry acquired between 2008 and 2016 by boat surveying. The HEC-RAS model was implemented on the Athabasca River to simulate WL using cross-sections spaced by 100 m. An image histogram thresholding method was applied on each Radarsat-2 image to derive WE. WE were then compared against each cross-section to identify those were the slope of the banks is not too abrupt and therefore amenable to extract WL. 139 observations of WL at different locations along the river reach and with streamflow measurements were used to calibrate the HEC-RAS model. The RMSE between SAR-derived and simulated WL is under 0.35 m. Validation was performed using in situ observations of WL measured in 2008, 2012 and 2016. The RMSE between the simulated water levels calibrated with SAR images and in situ observations is less than 0.20 m. In addition, a critical success index (CSI) was

Moiré Effect: Index and the Digital Image

Directory of Open Access Journals (Sweden)

Stella Baraklianou

2014-10-01

Full Text Available The moiré effect and phenomena are natural occurring geometric formations that appear during the super-position of grid structures. Most widely recognisable in colour printing practices, generally viewed on screens (computer and TV they are in most cases examples of interference within a signal or a code, unwanted visual mis-alignment. Especially in digital image capture, moiré patternings appear when a geometrically even pattern, like a fabric or close-up of fine texture, has an appearance of rippled water with blue or red hues of concentric circle formations. The intriguing pattern formation in this case points back not only to the mis-alignment of frequencies, but can be further seen as the intersection point of a speculative ontology for the index of the digital image. Moiré not only as a visually reproducible phenomenon or effect, but a field of vision that blurs the boundaries between analogue and digital, perception and affect, manifesting the photographic as a constant site of becoming, a site of immanence. The philosophy of Henri Bergson, Brian Massumi and Francois Laruelle will be explored alongside the moiré image and phenomenon, to see if there is such a speculative site underlining the becoming of the digital image and its repercussions in contemporary digital culture.

Simulating Visible/Infrared Imager Radiometer Suite Normalized Difference Vegetation Index Data Using Hyperion and MODIS

Science.gov (United States)

Ross, Kenton W.; Russell, Jeffrey; Ryan, Robert E.

2006-01-01

The success of MODIS (the Moderate Resolution Imaging Spectrometer) in creating unprecedented, timely, high-quality data for vegetation and other studies has created great anticipation for data from VIIRS (the Visible/Infrared Imager Radiometer Suite). VIIRS will be carried onboard the joint NASA/Department of Defense/National Oceanic and Atmospheric Administration NPP (NPOESS (National Polar-orbiting Operational Environmental Satellite System) Preparatory Project). Because the VIIRS instruments will have lower spatial resolution than the current MODIS instruments 400 m versus 250 m at nadir for the channels used to generate Normalized Difference Vegetation Index data, scientists need the answer to this question: how will the change in resolution affect vegetation studies? By using simulated VIIRS measurements, this question may be answered before the VIIRS instruments are deployed in space. Using simulated VIIRS products, the U.S. Department of Agriculture and other operational agencies can then modify their decision support systems appropriately in preparation for receipt of actual VIIRS data. VIIRS simulations and validations will be based on the ART (Application Research Toolbox), an integrated set of algorithms and models developed in MATLAB(Registerd TradeMark) that enables users to perform a suite of simulations and statistical trade studies on remote sensing systems. Specifically, the ART provides the capability to generate simulated multispectral image products, at various scales, from high spatial hyperspectral and/or multispectral image products. The ART uses acquired ( real ) or synthetic datasets, along with sensor specifications, to create simulated datasets. For existing multispectral sensor systems, the simulated data products are used for comparison, verification, and validation of the simulated system s actual products. VIIRS simulations will be performed using Hyperion and MODIS datasets. The hyperspectral and hyperspatial properties of Hyperion

A randomly-controlled study on the cardiac function at the early stage of return to the plains after short-term exposure to high altitude.

Directory of Open Access Journals (Sweden)

Qiquan Zhou

Full Text Available High altitude acclimatization and adaptation mechanisms have been well clarified, however, high altitude de-adaptation mechanism remains unclear. In this study, we conducted a controlled study on cardiac functions in 96 healthy young male who rapidly entered the high altitude (3700 m and returned to the plains (1500 m after 50 days. Ninety eight healthy male who remained at low altitude were recruited as control group. The mean pulmonary arterial pressure (mPAP, left ventricular ejection fraction (LVEF, left ventricular fraction shortening (LVFS, cardiac function index (Tei index were tested. Levels of serum creatine kinase isoform MB (CK-MB, lactate dehydrogenase isoenzyme-1 (LDH-1, endothelin-1 (ET-1, nitrogen oxide (NO, serum hypoxia-inducible factor-1α (HIF-1α, 8-iso-prostaglandin F(2α (8-iso PGF(2α, superoxide dismutase (SOD and malonaldehyde (MDA were measured at an altitude of 3700 m and 1500 m respectively. The results showed that after short-term exposure to high altitude mPAP and Tei index increased significantly, while LVEF and LVFS decreased significantly. These changes were positively correlated with altitude. On the 15(th day after the subjects returned to low altitude, mPAP, LVEF and LVFS levels returned to the same level as those of the control subjects, but the Tei index in the returned subjects was still significantly higher than that in the control subjects (P<0.01. We also found that changes in Tei index was positively correlated with mPAP, ET-1, HIF-1α and 8-iso PGF(2α levels, and negatively correlated with the level of NO, LVEF, LVFS, CK-MB and LDH-1. These findings suggest that cardiac function de-adapts when returning to the plains after short-term exposure to high altitude and the function recovery takes a relatively long time.

Antecedent precipitation index determined from CST estimates of rainfall

Science.gov (United States)

Martin, David W.

1992-01-01

This paper deals with an experimental calculation of a satellite-based antecedent precipitation index (API). The index is also derived from daily rain images produced from infrared images using an improved version of GSFC's Convective/Stratiform Technique (CST). API is a measure of soil moisture, and is based on the notion that the amount of moisture in the soil at a given time is related to precipitation at earlier times. Four different CST programs as well as the Geostationary Operational Enviroment Satellite (GOES) Precipitation Index developed by Arkin in 1979 are compared to experimental results, for the Mississippi Valley during the month of July. Rain images are shown for the best CST code and the ARK program. Comparisons are made as to the accuracy and detail of the results for the two codes. This project demonstrates the feasibility of running the CST on a synoptic scale. The Mississippi Valley case is well suited for testing the feasibility of monitoring soil moisture by means of CST. Preliminary comparisons of CST and ARK indicate significant differences in estimates of rain amount and distribution.

Impacto aromático dos componentes voláteis do café soluvél : uma abordagem analítica e sensorial

OpenAIRE

Denisley Gentil Bassoli

2006-01-01

A aplicação de métodos instrumentais e analíticos cada vez mais sofisticados tem aprimorado a avaliação objetiva do aroma, característica determinante da qualidade de alimentos e de sua aceitabilidade, tendo sido detectados mais de oitocentos componentes voláteis no café torrado, mas com escassa informação disponível para café solúvel. Atualmente, a produção mundial de café solúvel é de aproximadamente quinhentas mil toneladas, sendo o Brasil um importante produtor. O café solúvel é obtido a ...

Relationship between body mass index and women's body image, self-esteem and eating behaviours in pregnancy: a cross-cultural study.

Science.gov (United States)

Shloim, Netalie; Hetherington, Marion M; Rudolf, Mary; Feltbower, Richard G

2015-04-01

This study examined the relationship between self-esteem, restrained eating, body image and body mass index during pregnancy. A total of 110 pregnant Israeli and UK women completed the Rosenberg Self-Esteem Questionnaire, the Dutch Eating Behaviour Questionnaire, scales to assess body image and demographics. Body mass index was calculated from antenatal records. Regression modelling determined the relationship between variables, countries and body mass index categories. High correlations were found between body image and body mass index with significantly higher body dissatisfaction for Israeli women. Self-esteem scores for pregnant women were similar to those reported for non-pregnant women. Poorer body image and higher prevalence of restrained eating were found in healthy weight Israeli women. © The Author(s) 2013.

Automatic Detection of Mitosis and Nuclei from Cytogenetic Images by CellProfiler Software for Mitotic Index Estimation

International Nuclear Information System (INIS)

Gonzalez, Jorge Ernesto; Romero, Ivonne; Garcia, Omar; Radl, Analia; Di Giorgio, Marina; Barquinero, Joan Francesc

2016-01-01

Mitotic Index (MI) estimation expressed as percentage of mitosis plays an important role as quality control endpoint. To this end, MI is applied to check the lot of media and reagents to be used throughout the assay and also to check cellular viability after blood sample shipping, indicating satisfactory/unsatisfactory conditions for the progression of cell culture. The objective of this paper was to apply the CellProfiler open-source software for automatic detection of mitotic and nuclei figures from digitized images of cultured human lymphocytes for MI assessment, and to compare its performance to that performed through semi-automatic and visual detection. Lymphocytes were irradiated and cultured for mitosis detection. Sets of images from cultures were analyzed visually and findings were compared with those using CellProfiler software. The CellProfiler pipeline includes the detection of nuclei and mitosis with 80% sensitivity and more than 99% specificity. We conclude that CellProfiler is a reliable tool for counting mitosis and nuclei from cytogenetic images, saves considerable time compared to manual operation and reduces the variability derived from the scoring criteria of different scorers. The CellProfiler automated pipeline achieves good agreement with visual counting workflow, i.e. it allows fully automated mitotic and nuclei scoring in cytogenetic images yielding reliable information with minimal user intervention. (authors)

Joint Textual And Visual Cues For Retrieving Images Using Latent Semantic Indexing

OpenAIRE

Pecenovic, Zoran; Ayer, Serge; Vetterli, Martin

2001-01-01

In this article we present a novel approach of integrating textual and visual descriptors of images in a unified retrieval structure. The methodology, inspired from text retrieval and information filtering is based on Latent Semantic Indexing (LS1).

Equilíbrio líquido-vapor de solventes na presença de solutos não voláteis

OpenAIRE

Parente, Bruno Miguel Ramos

2009-01-01

Neste trabalho estudou-se o efeito da adição de alguns sais e líquidos iónicos no equilíbrio líquido-vapor (ELV) de algumas misturas importantes na indústria química, tais como etanol + água, 1-propanol + água, 2-propanol + água, acetona + metanol, acetato de metilo + metanol e clorofórmio + etanol. O conjunto de solutos não voláteis estudados é formado por Ca(NO3)2, CuCl2, NaI, KI, LiNO3, LiCl, NaSCN, KCH3COO, CaCl2, [BMIM][Cl] e [EMIM][triflate]. Em primeiro lugar, realizo...

All-solid tellurite optical fiber with transversely disordered refractive index profile and its optical image transport performance

Science.gov (United States)

Tong, Hoang Tuan; Kuroyanagi, Shunei; Suzuki, Takenobu; Ohishi, Yasutake

2018-02-01

All-solid tellurite-glass optical rod and fiber with transversely-disordered refractive index profile were successfully fabricated to study the transport of infrared images by using transverse localization of light. The fabrication was carried out by using stack-and-draw and rod-in-tube techniques. The fabricated tellurite optical rod and fiber were composed of high-index and low-index units which were arranged randomly in the transverse plane but were invariant in the longitudinal direction. The diameter of each unit was approximately 1.0 μm. The high-index and low-index materials were TeO2-Li2O-WO3-MoO3-Nb2O5 (TLWMN) glass and TeO2-ZnO-Na2O-La2O3 (TZNL) glass, respectively. At 1550 nm, their refractive index difference Δn is 0.096. To investigate the optical image transport capability, A CW laser light at 1550 nm was used as an input probe beam and the 1951 U.S. Air Force test target was installed in front of 10-cm-long segments of the fabricated rod and fiber in the experimental setup. The output signal was recorded by a beam profiler. As a result, clear transported images of numbers and lines on the test target were obtained.

Volatile profile of the headspace fraction of "assa-peixe" (Vernonia sp. honeys Perfil dos compostos voláteis presentes na fração "headspace" de méis de assa-peixe

Directory of Open Access Journals (Sweden)

Mariana Carvalho Ribeiro

2008-03-01

Full Text Available The volatile compounds were isolated from the headspace fraction of "assa-peixe" honeys by adsorptive column chromatography, eluted with acetone and analysed by GC-FID and GC-MS. Volatile compounds were separated using a polar phase column. Low- and medium-boiling point volatile compounds predominated in the headspace. A large proportion of 3-penten-2-one (80.5 ± 13.9 µg.kg-1 and benzaldehyde (25.9 ± 4.2 µg.kg-1 was found in the headspace fraction, while 2-penten-1-ol, 3-hexenyl butanoate, octadecane and hexanoic acid (Os compostos voláteis da fração "Headspace" de méis de assa-peixe foram adsorvidos pela técnica de cromatografia de adsorção, eluídos com acetona e analisados através da CG/DIC e CG/EM usando coluna polar de sílica fundida. Os compostos voláteis de baixo e médio ponto de ebulição predominaram na fração "headspace". Foi achada uma grande proporção de 3-penten-2-ona (80,5 ± 13,9 µg.kg-1 e benzaldeído (25,9 ± 4,2 µg.kg-1, enquanto o 2-penten-1-ol, o hexanoato de 3-hexenila, o octadecano e o ácido hexanóico (<0,01 µg.kg-1 foram compostos minoritários. Um total de doze compostos voláteis foi identificado, sendo cinco descritos pela primeira vez no mel de assa-peixe. Destes cinco, a 3-penten-2-ona, o dodecano, o tridecano e o benzaldeído foram definitivamente identificados na fração "headspace" dos méis de assa-peixe brasileiro.

Cine dyscontractility index: A novel marker of mechanical dyssynchrony that predicts response to cardiac resynchronization therapy.

Science.gov (United States)

Werys, Konrad; Petryka-Mazurkiewicz, Joanna; Błaszczyk, Łukasz; Miśko, Jolanta; Śpiewak, Mateusz; Małek, Łukasz A; Mazurkiewicz, Łukasz; Miłosz-Wieczorek, Barbara; Marczak, Magdalena; Kubik, Agata; Dąbrowska, Agnieszka; Piątkowska-Janko, Ewa; Sawionek, Błażej; Wijesurendra, Rohan; Piechnik, Stefan K; Bogorodzki, Piotr

2016-12-01

To investigate whether magnetic resonance imaging (MRI) cine-derived dyssynchrony indices provide additional information compared to conventional tagged MRI (tMRI) acquisitions in heart failure patients undergoing cardiac resynchronization therapy (CRT). Patients scheduled for CRT (n = 52) underwent preprocedure MRI including cine and tMRI acquisitions. Segmental strain curves were calculated for both cine and tMRI to produce a range of standard indices for direct comparison between modalities. We also proposed and evaluated a novel index of "dyscontractility," which detects the presence of focal areas with paradoxically positive circumferential strain. Across conventional strain indices, there was only moderate-to-poor (R = 0.3-0.6) correlation between modalities; eight cine-derived indices showed statistically significant (P cine images (cine dyscontractility index, "CDI") was the single best predictor of clinical response to CRT (area under the curve AUC = 0.81, P Cine-derived strain indices offer potentially new information compared to tMRI. Specifically, the novel CDI is most strongly linked to response to cardiac resynchronization therapy in a contemporary patient cohort. It utilizes readily available MRI data, is relatively straightforward to process, and compares favorably with any conventional tagging index. J. Magn. Reson. Imaging 2016;44:1483-1492. © 2016 International Society for Magnetic Resonance in Medicine.

Measurement and comparison of remotely derived leaf area index predictors

Science.gov (United States)

Jensen, Ryan Russell

Environmental change occurs in response to both natural and anthropogenic causes. As the world's human population continues to increase, anthropogenic change will also increase. These changes affect the health and vigor of forests throughout the world, including those in north central Florida. Leaf Area Index (LAI), the amount of leaf area per unit ground area, is an important biophysical variable that is directly related to rates of atmospheric gas exchange, biomass partitioning, and productivity. While global and local models that map biophysical parameters are prevalent in the literature, landscape to regional scale models are less common. Therefore, the ability to map and monitor LAI over landscape to regional scale areas is essential for understanding medium scale biophysical properties and how these properties affect biogeochemical cycling, biomass accumulation, and primary productivity. This study develops and verifies several new models to estimate LAI using in situ field measurements throughout north central Florida, Landsat Thematic Mapper remotely sensed imagery, remotely derived vegetation indices, simple and multiple regression, and artificial neural networks (ANNs). This study concludes that while multiple band regression and regression with individual vegetation indices (Normalized Difference Vegetation Index, Soil Adjusted Vegetation Index, Simple Ratio, and Greenness Vegetation Index) can estimate LAI, the most accurate way to estimate regional scale LAI is to train an ANN using in situ LAI data and remote sensing brightness values measured from six different portions of the electromagnetic spectrum. The new ANN method of estimating LAI is then applied to two forest ecology studies. The first study analyzes LAI in longleaf pine/turkey oak sandhills as a function of time since last burn. It concludes that in the absence of fire, sandhill LAI increases, and this may be useful for identifying where prescribed burns need to be done. The second study

Derivative-based scale invariant image feature detector with error resilience.

Science.gov (United States)

Mainali, Pradip; Lafruit, Gauthier; Tack, Klaas; Van Gool, Luc; Lauwereins, Rudy

2014-05-01

We present a novel scale-invariant image feature detection algorithm (D-SIFER) using a newly proposed scale-space optimal 10th-order Gaussian derivative (GDO-10) filter, which reaches the jointly optimal Heisenberg's uncertainty of its impulse response in scale and space simultaneously (i.e., we minimize the maximum of the two moments). The D-SIFER algorithm using this filter leads to an outstanding quality of image feature detection, with a factor of three quality improvement over state-of-the-art scale-invariant feature transform (SIFT) and speeded up robust features (SURF) methods that use the second-order Gaussian derivative filters. To reach low computational complexity, we also present a technique approximating the GDO-10 filters with a fixed-length implementation, which is independent of the scale. The final approximation error remains far below the noise margin, providing constant time, low cost, but nevertheless high-quality feature detection and registration capabilities. D-SIFER is validated on a real-life hyperspectral image registration application, precisely aligning up to hundreds of successive narrowband color images, despite their strong artifacts (blurring, low-light noise) typically occurring in such delicate optical system setups.

Segmentation Technique for Image Indexing and Retrieval on Discrete Cosines Domain

Directory of Open Access Journals (Sweden)

Suhendro Yusuf Irianto

2013-03-01

Full Text Available This paper uses region growing segmentation technique to segment the Discrete Cosines (DC  image. The problem of content Based image retrieval (CBIR is the luck of accuracy in matching between image query and image in the database as it matches object and background in the same time.   This the reason previous CBIR techniques inaccurate and time consuming. The CBIR   based on the segmented region proposed in this work  separates object from background as CBIR need only match the object not the background.  By using region growing technique on DC image, it reduces the number of image       regions.    The proposed of recursive region growing is not new technique but its application on DC images to build    indexing keys is quite new and not yet presented by many     authors. The experimental results show  that the proposed methods on   segmented images present good precision which are higher than 0.60 on all classes . It can be concluded that  region growing segmented based CBIR more efficient    compare to DC images  in term of their precision 0.59 and 0.75, respectively. Moreover,  DC based CBIR  can save time and simplify algorithm compare to DCT images.

A new iterative algorithm to reconstruct the refractive index.

Science.gov (United States)

Liu, Y J; Zhu, P P; Chen, B; Wang, J Y; Yuan, Q X; Huang, W X; Shu, H; Li, E R; Liu, X S; Zhang, K; Ming, H; Wu, Z Y

2007-06-21

The latest developments in x-ray imaging are associated with techniques based on the phase contrast. However, the image reconstruction procedures demand significant improvements of the traditional methods, and/or new algorithms have to be introduced to take advantage of the high contrast and sensitivity of the new experimental techniques. In this letter, an improved iterative reconstruction algorithm based on the maximum likelihood expectation maximization technique is presented and discussed in order to reconstruct the distribution of the refractive index from data collected by an analyzer-based imaging setup. The technique considered probes the partial derivative of the refractive index with respect to an axis lying in the meridional plane and perpendicular to the propagation direction. Computer simulations confirm the reliability of the proposed algorithm. In addition, the comparison between an analytical reconstruction algorithm and the iterative method has been also discussed together with the convergent characteristic of this latter algorithm. Finally, we will show how the proposed algorithm may be applied to reconstruct the distribution of the refractive index of an epoxy cylinder containing small air bubbles of about 300 micro of diameter.

Body Image, Food Addiction, Depression, and Body Mass Index in University Students.

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Şanlier, Nevin; Türközü, Duygu; Toka, Onur

2016-01-01

The relationship between body image, depression, food addiction and body mass index (BMI) and differences in these variables due to gender and field of education have not been studied extensively. This study was conducted on a total of 793 university students (20.19 ± 1.90 years). The Beck Depression Inventory, Yale Food Addiction, and Body Image Scale were used. It was determined that body image scores of females and individuals enrolled in health sciences programs were lower compared to those of males and those enrolled in the social sciences. There was a negative relationship between body image and depression and food addiction scores. There was a positive relationship between food addiction and depression scores, in addition to a positive relationship between food addiction and BMI.

Automatic Detection of Mitosis and Nuclei From Cytogenetic Images by CellProfiler Software for Mitotic Index Estimation.

Science.gov (United States)

González, Jorge Ernesto; Radl, Analía; Romero, Ivonne; Barquinero, Joan Francesc; García, Omar; Di Giorgio, Marina

2016-12-01

Mitotic Index (MI) estimation expressed as percentage of mitosis plays an important role as quality control endpoint. To this end, MI is applied to check the lot of media and reagents to be used throughout the assay and also to check cellular viability after blood sample shipping, indicating satisfactory/unsatisfactory conditions for the progression of cell culture. The objective of this paper was to apply the CellProfiler open-source software for automatic detection of mitotic and nuclei figures from digitized images of cultured human lymphocytes for MI assessment, and to compare its performance to that performed through semi-automatic and visual detection. Lymphocytes were irradiated and cultured for mitosis detection. Sets of images from cultures were analyzed visually and findings were compared with those using CellProfiler software. The CellProfiler pipeline includes the detection of nuclei and mitosis with 80% sensitivity and more than 99% specificity. We conclude that CellProfiler is a reliable tool for counting mitosis and nuclei from cytogenetic images, saves considerable time compared to manual operation and reduces the variability derived from the scoring criteria of different scorers. The CellProfiler automated pipeline achieves good agreement with visual counting workflow, i.e. it allows fully automated mitotic and nuclei scoring in cytogenetic images yielding reliable information with minimal user intervention. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Image-guided, Laser-based Fabrication of Vascular-derived Microfluidic Networks

OpenAIRE

Heintz, Keely A.; Mayerich, David; Slater, John H.

2017-01-01

This detailed protocol outlines the implementation of image-guided, laser-based hydrogel degradation for the fabrication of vascular-derived microfluidic networks embedded in PEGDA hydrogels. Here, we describe the creation of virtual masks that allow for image-guided laser control; the photopolymerization of a micromolded PEGDA hydrogel, suitable for microfluidic network fabrication and pressure head-driven flow; the setup and use of a commercially available laser scanning confocal microscope...

Latent cardiac dysfunction as assessed by echocardiography in bed-bound patients following cerebrovascular accidents: comparison with nutritional status.

Science.gov (United States)

Masugata, Hisashi; Senda, Shoichi; Goda, Fuminori; Yoshihara, Yumiko; Yoshikawa, Kay; Fujita, Norihiro; Himoto, Takashi; Okuyama, Hiroyuki; Taoka, Teruhisa; Imai, Masanobu; Kohno, Masakazu

2007-07-01

The aim of this study was to elucidate the cardiac function in bed-bound patients following cerebrovascular accidents. In accord with the criteria for activities of daily living (ADL) of the Japanese Ministry of Health, Labour and Welfare, 51 age-matched poststroke patients without heart disease were classified into 3 groups: rank A (house-bound) (n = 16, age, 85 +/- 6 years), rank B (chair-bound) (n = 16, age, 84 +/- 8 years), and rank C (bed-bound) (n = 19, age, 85 +/- 9 years). Using echocardiography, the left ventricular (LV) diastolic function was assessed by the ratio of early filling (E) and atrial contraction (A) transmitral flow velocities (E/A) of LV inflow. LV systolic function was assessed by LV ejection fraction (LVEF), and the Tei index was also measured to assess both LV systolic and diastolic function. No difference was observed in the E/A and LVEF among the 3 groups. The Tei index was higher in rank C (0.56 +/- 0.17) than in rank A (0.39 +/- 0.06) and rank B (0.48 +/- 0.17), and a statistically significant difference was observed between rank A and rank C (P cerebrovascular accidents. The Tei index may be a useful index of cardiac dysfunction in bed-bound patients because it is independent of the cardiac loading condition.

Time-resolved computed tomography of the liver: retrospective, multi-phase image reconstruction derived from volumetric perfusion imaging

Energy Technology Data Exchange (ETDEWEB)

Fischer, Michael A.; Kartalis, Nikolaos; Aspelin, Peter; Albiin, Nils; Brismar, Torkel B. [Karolinska University Hospital, Division of Medical Imaging and Technology, Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institutet, Stockholm (Sweden); Leidner, Bertil; Svensson, Anders [Karolinska University Hospital, Division of Medical Imaging and Technology, Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institutet, Stockholm (Sweden); Karolinska University Hospital Huddinge, Department of Radiology, Stockholm (Sweden)

2014-01-15

To assess feasibility and image quality (IQ) of a new post-processing algorithm for retrospective extraction of an optimised multi-phase CT (time-resolved CT) of the liver from volumetric perfusion imaging. Sixteen patients underwent clinically indicated perfusion CT using 4D spiral mode of dual-source 128-slice CT. Three image sets were reconstructed: motion-corrected and noise-reduced (MCNR) images derived from 4D raw data; maximum and average intensity projections (time MIP/AVG) of the arterial/portal/portal-venous phases and all phases (total MIP/ AVG) derived from retrospective fusion of dedicated MCNR split series. Two readers assessed the IQ, detection rate and evaluation time; one reader assessed image noise and lesion-to-liver contrast. Time-resolved CT was feasible in all patients. Each post-processing step yielded a significant reduction of image noise and evaluation time, maintaining lesion-to-liver contrast. Time MIPs/AVGs showed the highest overall IQ without relevant motion artefacts and best depiction of arterial and portal/portal-venous phases respectively. Time MIPs demonstrated a significantly higher detection rate for arterialised liver lesions than total MIPs/AVGs and the raw data series. Time-resolved CT allows data from volumetric perfusion imaging to be condensed into an optimised multi-phase liver CT, yielding a superior IQ and higher detection rate for arterialised liver lesions than the raw data series. (orig.)

Purine derivatives/creatinine ratio as an index of microbial protein synthesis in lactating Holstein cows

International Nuclear Information System (INIS)

Orellana, R.; Pulido, P.; Briones, M.; Sarabia, A.

2004-01-01

Three experiments were conducted to study creatinine excretion in milking cows, and its relationship to food intake and purine derivatives (PD) excretion as an index of microbial N synthesized in the rumen. In the first experiment, differences in creatinine determination method were studied: creatinine excretion was 26.8 ± 1.2 and 27.4 ± 2.2 mg/kg live weight, or 1,175.39 ± 74.69 and 1,199.9 ± 103.9 mmol/kgW 0.75 respectively for HPLC and colorimetry analysis. In the second experiment, the effect of concentrate supplement on the PDC index was studied. The inclusion of different levels of concentrate (0, 16, 33 and 50%) increased the PDC index significantly. The PDC index (Y) also showed a significant relationship with DOMI (X, kg/d): Y 16.85 X + 6.23; R 2 =0.84. Total PD excretion was calculated assuming constant daily excretion of creatinine (1.199 mmol/kgW 0.75 ). In the third experiment the effect of different roughage on the PDC index was studied. The substitution of a 23% of rye grass (Lolium sp.) silage by alkali treated wheat straw did not modify DOMI and the PDC index although among groups there was a significant decrease in milk production (1.5 L/cow/d) and in growth rate (-380 g/cow/d). (author)

Topographic soil wetness index derived from combined Alaska-British Columbia datasets for the Gulf of Alaska region

Science.gov (United States)

D'Amore, D. V.; Biles, F. E.

2016-12-01

The flow of water is often highlighted as a priority in land management planning and assessments related to climate change. Improved measurement and modeling of soil moisture is required to develop predictive estimates for plant distributions, soil moisture, and snowpack, which all play important roles in ecosystem planning in the face of climate change. Drainage indexes are commonly derived from GIS tools with digital elevation models. Soil moisture classes derived from these tools are useful digital proxies for ecosystem functions associated with the concentration of water on the landscape. We developed a spatially explicit topographically derived soil wetness index (TWI) across the perhumid coastal temperate rainforest (PCTR) of Alaska and British Columbia. Developing applicable drainage indexes in complex terrain and across broad areas required careful application of the appropriate DEM, caution with artifacts in GIS covers and mapping realistic zones of wetlands with the indicator. The large spatial extent of the model has facilitated the mapping of forest habitat and the development of water table depth mapping in the region. A key element of the TWI is the merging of elevation datasets across the US-Canada border where major rivers transect the international boundary. The unified TWI allows for seemless mapping across the international border and unified ecological applications. A python program combined with the unified DEM allows end users to quickly apply the TWI to all areas of the PCTR. This common platform can facilitate model comparison and improvements to local soil moisture conditions, generation of streamflow, and ecological site conditions. In this presentation we highlight the application of the TWI for mapping risk factors related to forest decline and the development of a regional water table depth map. Improved soil moisture maps are critical for deriving spatial models of changes in soil moisture for both plant growth and streamflow across

Image quality and volume computed tomography air kerma index (Cvol) evaluation in Recife

International Nuclear Information System (INIS)

Andrade, Marcos Ely Almeida

2008-01-01

The Computed Tomography (CT) is an important diagnostic imaging method, widely used. However, in spite of all the advantages and technologic advances within the CT scanners, the tomographic procedures result in high absorbed doses to patients. The main objective of this work was to perform a dosimetric study of CT scanners located at Recife and to evaluate the image quality on CT examinations in these equipment. The volume CT air kerma index (C VOL ) and air kerma length product (P KL,CT ) were estimated. These values were calculated using normalized weighted air kerma indexes in CT standard dosimetry phantoms ( n C W ), supplied by ImPACT group for several CT scanners, and the scan parameters of routine head, routine chest and hi-resolution chest CT exams performed at 20 institutions. The irradiation parameters of 15 adult patients for each CT procedure were registered at six participating centres, at which the phantom from the American College of Radiology (ACR) CT accreditation protocol was used for the image quality measurements. For routine head exams, the C VOL values varied between 12 and 58 mGy (at the posterior fossa) and 15 to 58 mGy (at the cerebrum) and the P KL,CT , from 150 to 750 mGy·cm. The C VOL values for routine chest procedures varied from 3 to 26 mGy and the P KL,CT , between 120 and 460 mGy·cm. In relation to Hi-resolution chest exams, C VOL values were from 1.0 to 2.7 mGy and the P KL,CT values varied between 24 and 67 mGy·cm. The image quality evaluations results showed that almost all scanners presented at least one inadequacy. One of the equipment presented faults at 70% of the tests. With regard to the image noise, only two scanners presented acceptable results. From these results, it is possible to conclude that the volume CT air kerma index values are lower than the European reference levels. However, the image quality of these CT scanners does not attend the ACR requirements, suggesting the need to implement quality assurance

Semantics-Based Intelligent Indexing and Retrieval of Digital Images - A Case Study

Science.gov (United States)

Osman, Taha; Thakker, Dhavalkumar; Schaefer, Gerald

The proliferation of digital media has led to a huge interest in classifying and indexing media objects for generic search and usage. In particular, we are witnessing colossal growth in digital image repositories that are difficult to navigate using free-text search mechanisms, which often return inaccurate matches as they typically rely on statistical analysis of query keyword recurrence in the image annotation or surrounding text. In this chapter we present a semantically enabled image annotation and retrieval engine that is designed to satisfy the requirements of commercial image collections market in terms of both accuracy and efficiency of the retrieval process. Our search engine relies on methodically structured ontologies for image annotation, thus allowing for more intelligent reasoning about the image content and subsequently obtaining a more accurate set of results and a richer set of alternatives matchmaking the original query. We also show how our well-analysed and designed domain ontology contributes to the implicit expansion of user queries as well as presenting our initial thoughts on exploiting lexical databases for explicit semantic-based query expansion.

Effect of body mass index on shifts in ultrasound-based image-guided intensity-modulated radiation therapy for abdominal malignancies

International Nuclear Information System (INIS)

Choi, Mehee; Fuller, Clifton D.; Wang, Samuel J.; Siddiqi, Ather; Wong, Adrian; Thomas, Charles R.; Fuss, Martin

2009-01-01

Background and purpose: We investigated whether corrective shifts determined by daily ultrasound-based image-guidance correlate with body mass index (BMI) of patients treated with image-guided intensity-modulated radiation therapy (IG-IMRT) for abdominal malignancies. The utility of daily image-guidance, particularly for patients with BMI > 25.0, is examined. Materials and methods: Total 3162 ultrasound-directed shifts were performed in 86 patients. Direction and magnitude of shifts were correlated with pretreatment BMI. Bivariate statistical analysis and analysis of set-up correction data were performed using systematic and random error calculations. Results: Total 2040 daily alignments were performed. Average 3D vector of set-up correction for all patients was 12.1 mm/fraction. Directional and absolute shifts and 3D vector length were significantly different between BMI cohorts. 3D displacement averaged 4.9 mm/fraction and 6.8mm/fraction for BMI ≤ 25.0 and BMI > 25.0, respectively. Systematic error in all axes and 3D vector was significantly greater for BMI > 25.0. Differences in random error were not statistically significant. Conclusions: Set-up corrections derived from daily ultrasound-based IG-IMRT of abdominal tumors correlated with BMI. Daily image-guidance may improve precision of IMRT delivery with benefits assessed for the entire population, particularly patients with increased habitus. Requisite PTV margins suggested in the absence of daily image-guidance are significantly greater in patients with BMI > 25.0.

Embolia gasosa venosa inadvertida durante cesariana: bolsas retráteis ​​para líquidos intravenosos sem saídas autovedantes oferecem riscos. Relato de caso

Directory of Open Access Journals (Sweden)

Mefkur Bakan

2013-08-01

Full Text Available O anestesiologista deve estar ciente das causas, do diagnóstico e do tratamento de embolia venosa e adotar padrões de prática para prevenir sua ocorrência. Embora a embolia gasosa seja uma complicação conhecida da cesariana, descrevemos um caso raro de desatenção que causou embolia gasosa iatrogênica quase fatal durante uma cesariana sob raquianestesia. uma das razões para o uso de bolsas autorretráteis para infusão em vez dos frascos convencionais de vidro ou plástico é a precaução contra embolia gasosa. Também demonstramos o risco de embolia venosa com o uso de dois tipos de bolsas plásticas retráteis (à base de cloreto de polivinil [PVC] e de polipropileno para líquidos intravenosos. As bolsas para líquidos sem saídas autovedantes apresentam risco de embolia gasosa se o sistema de fechamento estiver quebrado, enquanto a flexibilidade da bolsa limita a quantidade de entrada de ar. bolsas à base de pvc, que têm mais flexibilidade, apresentam risco significativamente menor de entrada de ar quando o equipo de administração intravenosa (IV é desconectado da saída. usar uma bolsa pressurizada para infusão rápida sem verificar e esvaziar todo o ar da bolsa IV pode ser perigoso.

Paradox image: a noninvasive index of regional left-ventricular dyskinesis

International Nuclear Information System (INIS)

Holman, B.L.; Wynne, J.; Idoine, J.; Zielonka, J.; Neill, J.

1979-01-01

The paradox image, a functional image of regional dyskinesis derived from the equilibrium (gated) radionuclide ventriculogram, was constructed by subtracting the background-corrected end-diastolic frame from the background-corrected end-systolic frame. In 11 patients showing dyskinesis by contrast ventriculography, the percentage of left-ventricular picture elements containing paradox ranged from 3.6 to 55.6% (21.44% +- 4.45 s.e.m.). In 11 patients with normokinesis and in eight patients with hypookinesis by contrast ventriculography, the left-ventricular picture elements demonstrating paradox were less than 1.1% in all cases. In nine patients with akinesis, the percentage of left-ventricular picture elements containing paradox was 2.05% +- 0.96 s.e.m. and was less than 2% in seven patients. There was also an excellent agreement between the location of dyskinesis on the paradox image and that by contrast ventriculography. The paradox image is a sensitive indicator of left-ventricular dyskinesis and should be useful in the evaluation of patients with suspected left-ventricular asynergy

Photosynthetic Efficiency of Northern Forest Ecosystems Using a MODIS-Derived Photochemical Reflectance Index (PRI)

Science.gov (United States)

Middleton, E. M.; Huemmrich, K. F.; Landis, D. R.; Black, T. A.; Barr, A. G.; McCaughey, J. H.

2016-01-01

This study evaluates a direct remote sensing approach from space for the determination of ecosystem photosynthetic light use efficiency (LUE), through measurement of vegetation reflectance changes expressed with the Photochemical Reflectance Index (PRI). The PRI is a normalized difference index based on spectral changes at a physiologically active wavelength (approximately 531 nanometers) as compared to a reference waveband, and is only available from a very few satellites. These include the two Moderate-Resolution Imaging Spectroradiometers (MODIS) on the Aqua and Terra satellites each of which have a narrow (10-nanometer) ocean band centered at 531 nanometers. We examined several PRI variations computed with candidate reference bands, since MODIS lacks the traditional 570-nanometer reference band. The PRI computed using MODIS land band 1 (620-670 nanometers) gave the best performance for daily LUE estimation. Through rigorous statistical analyses over a large image collection (n equals 420), the success of relating in situ daily tower-derived LUE to MODIS observations for northern forests was strongly influenced by satellite viewing geometry. LUE was calculated from CO2 fluxes (moles per moles of carbon absorbed quanta) measured at instrumented Canadian Carbon Program flux towers in four Canadian forests: a mature fir site in British Columbia, mature aspen and black spruce sites in Saskatchewan, and a mixed deciduous/coniferous forest site in Ontario. All aspects of the viewing geometry had significant effects on the MODIS-PRI, including the view zenith angle (VZA), the view azimuth angle, and the displacement of the view azimuth relative to the solar principal plane, in addition to illumination related variables.Nevertheless, we show that forward scatter sector views (VZA, 16 degrees-45 degrees) provided the strongest relationships to daily LUE, especially those collected in the early afternoon by Aqua (r squared = 0.83, RMSE (root mean square error) equals 0

The relationship between the retinal image quality and the refractive index of defects arising in IOL: numerical analysis

Science.gov (United States)

Geniusz, Malwina

2017-09-01

The best treatment for cataract patients, which allows to restore clear vision is implanting an artificial intraocular lens (IOL). The image quality of the lens has a significant impact on the quality of patient's vision. After a long exposure the implant to aqueous environment some defects appear in the artificial lenses. The defects generated in the IOL have different refractive indices. For example, glistening phenomenon is based on light scattering on the oval microvacuoles filled with an aqueous humor which refractive index value is about 1.34. Calcium deposits are another example of lens defects and they can be characterized by the refractive index 1.63. In the presented studies it was calculated how the difference between the refractive indices of the defect and the refractive index of the lens material affects the quality of image. The OpticStudio Professional program (from Radiant Zemax, LLC) was used for the construction of the numerical model of the eye with IOL and to calculate the characteristics of the retinal image. Retinal image quality was described in such characteristics as Point Spread Function (PSF) and the Optical Transfer Function with amplitude and phase. The results show a strong correlation between the refractive indices difference and retinal image quality.

Changes of renal blood flow after ESWL: Assessment by ASL MR imaging, contrast enhanced MR imaging, and renal resistive index

Energy Technology Data Exchange (ETDEWEB)

Abd Ellah, Mohamed, E-mail: dr_m_hamdy2006@hotmail.co [Innsbruck Medical University, Radiology Dept., Anich St. 35, 6020 Innsbruck (Austria); Kremser, Christian, E-mail: christian.kremser@i-med.ac.a [Innsbruck Medical University, Radiology Dept., Anich St. 35, 6020 Innsbruck (Austria); Pallwein, Leo, E-mail: leo.pallwein-prettner@uki.a [Innsbruck Medical University, Radiology Dept., Anich St. 35, 6020 Innsbruck (Austria); Aigner, Friedrich, E-mail: friedrich.Aigner@uki.a [Innsbruck Medical University, Radiology Dept., Anich St. 35, 6020 Innsbruck (Austria); Schocke, Michael, E-mail: michael.schocke@i-med.ac.a [Innsbruck Medical University, Radiology Dept., Anich St. 35, 6020 Innsbruck (Austria); Peschel, Reinhard, E-mail: reinhard.peschel@uki.a [Innsbruck Medical University, Urology Dept., Anich St. 35, 6020 Innsbruck (Austria); Pedross, Florian, E-mail: florian.pedross@i-med.ac.a [Innsbruck Medical University, Medical Statistics Dept., Anich St. 35, 6020 Innsbruck (Austria); Pinggera, Germar-Michael, E-mail: germar.pinggera@uki.a [Innsbruck Medical University, Urology Dept., Anich St. 35, 6020 Innsbruck (Austria); Wolf, Christian, E-mail: christian.wolf@bkh-reutte.a [Innsbruck Medical University, Radiology Dept., Anich St. 35, 6020 Innsbruck (Austria); Alsharkawy, Mostafa A.M., E-mail: drmostafamri@yahoo.co [Assiut University, Radiology Dept., Assiut (Egypt); Jaschke, Werner, E-mail: werner.jaschke@i-med.ac.a [Innsbruck Medical University, Radiology Dept., Anich St. 35, 6020 Innsbruck (Austria); Frauscher, Ferdinand, E-mail: ferdinand.frauscher@uki.a [Innsbruck Medical University, Radiology Dept., Anich St. 35, 6020 Innsbruck (Austria)

2010-10-15

The annual incidence of stone formation is increased in the industrialised world. Extracorporeal shockwave lithotripsy is a non-invasive effective treatment of upper urinary tract stones. This study is aimed to evaluate changes of renal blood flow in patients undergoing extracorporeal shock wave lithotripsy (ESWL) by arterial spin labeling (ASL) MR imaging, contrast enhanced dynamic MR imaging, and renal resistive index (RI). Thirteen patients with nephrolithiasis were examined using MR imaging and Doppler ultrasound 12 h before and 12 h after ESWL. ASL sequence was done for both kidneys and followed by contrast enhanced MR imaging. In addition RI Doppler ultrasound measurements were performed. A significant increase in RI (p < 0.001) was found in both treated and untreated kidneys. ASL MR imaging also showed significant changes in both kidneys (p < 0.001). Contrast enhanced dynamic MR imaging did not show significant changes in the kidneys. ESWL causes changes in RI and ASL MR imaging, which seem to reflect changes in renal blood flow.

Mapping Deforestation in North Korea Using Phenology-Based Multi-Index and Random Forest

Directory of Open Access Journals (Sweden)

Yihua Jin

2016-12-01

Full Text Available Phenology-based multi-index with the random forest (RF algorithm can be used to overcome the shortcomings of traditional deforestation mapping that involves pixel-based classification, such as ISODATA or decision trees, and single images. The purpose of this study was to investigate methods to identify specific types of deforestation in North Korea, and to increase the accuracy of classification, using phenological characteristics extracted with multi-index and random forest algorithms. The mapping of deforestation area based on RF was carried out by merging phenology-based multi-indices (i.e., normalized difference vegetation index (NDVI, normalized difference water index (NDWI, and normalized difference soil index (NDSI derived from MODIS (Moderate Resolution Imaging Spectroradiometer products and topographical variables. Our results showed overall classification accuracy of 89.38%, with corresponding kappa coefficients of 0.87. In particular, for forest and farm land categories with similar phenological characteristic (e.g., paddy, plateau vegetation, unstocked forest, hillside field, this approach improved the classification accuracy in comparison with pixel-based methods and other classes. The deforestation types were identified by incorporating point data from high-resolution imagery, outcomes of image classification, and slope data. Our study demonstrated that the proposed methodology could be used for deciding on the restoration priority and monitoring the expansion of deforestation areas.

Determining the number of clusters for kernelized fuzzy C-means algorithms for automatic medical image segmentation

Directory of Open Access Journals (Sweden)

E.A. Zanaty

2012-03-01

Full Text Available In this paper, we determine the suitable validity criterion of kernelized fuzzy C-means and kernelized fuzzy C-means with spatial constraints for automatic segmentation of magnetic resonance imaging (MRI. For that; the original Euclidean distance in the FCM is replaced by a Gaussian radial basis function classifier (GRBF and the corresponding algorithms of FCM methods are derived. The derived algorithms are called as the kernelized fuzzy C-means (KFCM and kernelized fuzzy C-means with spatial constraints (SKFCM. These methods are implemented on eighteen indexes as validation to determine whether indexes are capable to acquire the optimal clusters number. The performance of segmentation is estimated by applying these methods independently on several datasets to prove which method can give good results and with which indexes. Our test spans various indexes covering the classical and the rather more recent indexes that have enjoyed noticeable success in that field. These indexes are evaluated and compared by applying them on various test images, including synthetic images corrupted with noise of varying levels, and simulated volumetric MRI datasets. Comparative analysis is also presented to show whether the validity index indicates the optimal clustering for our datasets.

Changes of renal blood flow after ESWL: assessment by ASL MR imaging, contrast enhanced MR imaging, and renal resistive index.

Science.gov (United States)

Abd Ellah, Mohamed; Kremser, Christian; Pallwein, Leo; Aigner, Friedrich; Schocke, Michael; Peschel, Reinhard; Pedross, Florian; Pinggera, Germar-Michael; Wolf, Christian; Alsharkawy, Mostafa A M; Jaschke, Werner; Frauscher, Ferdinand

2010-10-01

The annual incidence of stone formation is increased in the industrialised world. Extracorporeal shockwave lithotripsy is a non-invasive effective treatment of upper urinary tract stones. This study is aimed to evaluate changes of renal blood flow in patients undergoing extracorporeal shock wave lithotripsy (ESWL) by arterial spin labeling (ASL) MR imaging, contrast enhanced dynamic MR imaging, and renal resistive index (RI). Thirteen patients with nephrolithiasis were examined using MR imaging and Doppler ultrasound 12h before and 12h after ESWL. ASL sequence was done for both kidneys and followed by contrast enhanced MR imaging. In addition RI Doppler ultrasound measurements were performed. A significant increase in RI (pESWL causes changes in RI and ASL MR imaging, which seem to reflect changes in renal blood flow. Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.

Imaging-genomics reveals driving pathways of MRI derived volumetric tumor phenotype features in Glioblastoma

International Nuclear Information System (INIS)

Grossmann, Patrick; Gutman, David A.; Dunn, William D. Jr; Holder, Chad A.; Aerts, Hugo J. W. L.

2016-01-01

Glioblastoma (GBM) tumors exhibit strong phenotypic differences that can be quantified using magnetic resonance imaging (MRI), but the underlying biological drivers of these imaging phenotypes remain largely unknown. An Imaging-Genomics analysis was performed to reveal the mechanistic associations between MRI derived quantitative volumetric tumor phenotype features and molecular pathways. One hundred fourty one patients with presurgery MRI and survival data were included in our analysis. Volumetric features were defined, including the necrotic core (NE), contrast-enhancement (CE), abnormal tumor volume assessed by post-contrast T1w (tumor bulk or TB), tumor-associated edema based on T2-FLAIR (ED), and total tumor volume (TV), as well as ratios of these tumor components. Based on gene expression where available (n = 91), pathway associations were assessed using a preranked gene set enrichment analysis. These results were put into context of molecular subtypes in GBM and prognostication. Volumetric features were significantly associated with diverse sets of biological processes (FDR < 0.05). While NE and TB were enriched for immune response pathways and apoptosis, CE was associated with signal transduction and protein folding processes. ED was mainly enriched for homeostasis and cell cycling pathways. ED was also the strongest predictor of molecular GBM subtypes (AUC = 0.61). CE was the strongest predictor of overall survival (C-index = 0.6; Noether test, p = 4x10 −4 ). GBM volumetric features extracted from MRI are significantly enriched for information about the biological state of a tumor that impacts patient outcomes. Clinical decision-support systems could exploit this information to develop personalized treatment strategies on the basis of noninvasive imaging. The online version of this article (doi:10.1186/s12885-016-2659-5) contains supplementary material, which is available to authorized users

Content Based Radiographic Images Indexing and Retrieval Using Pattern Orientation Histogram

Directory of Open Access Journals (Sweden)

Abolfazl Lakdashti

2008-06-01

Full Text Available Introduction: Content Based Image Retrieval (CBIR is a method of image searching and retrieval in a  database. In medical applications, CBIR is a tool used by physicians to compare the previous and current  medical images associated with patients pathological conditions. As the volume of pictorial information  stored in medical image databases is in progress, efficient image indexing and retrieval is increasingly  becoming a necessity.  Materials and Methods: This paper presents a new content based radiographic image retrieval approach  based on histogram of pattern orientations, namely pattern orientation histogram (POH. POH represents  the  spatial  distribution  of  five  different  pattern  orientations:  vertical,  horizontal,  diagonal  down/left,  diagonal down/right and non-orientation. In this method, a given image is first divided into image-blocks  and  the  frequency  of  each  type  of  pattern  is  determined  in  each  image-block.  Then,  local  pattern  histograms for each of these image-blocks are computed.   Results: The method was compared to two well known texture-based image retrieval methods: Tamura  and  Edge  Histogram  Descriptors  (EHD  in  MPEG-7  standard.  Experimental  results  based  on  10000  IRMA  radiography  image  dataset,  demonstrate  that  POH  provides  better  precision  and  recall  rates  compared to Tamura and EHD. For some images, the recall and precision rates obtained by POH are,  respectively, 48% and 18% better than the best of the two above mentioned methods.    Discussion and Conclusion: Since we exploit the absolute location of the pattern in the image as well as  its global composition, the proposed matching method can retrieve semantically similar medical images.

Book Review: Instagram and contemporary image, Lev Manovich

Directory of Open Access Journals (Sweden)

Carla Barrio Romera

2018-05-01

Full Text Available Book Review: Instagram and contemporary image, Lev Manovich, California Institute for Telecommunication and Information & The Graduate Center, City University of New York (CUNY, Cultural Analytics Lab, 2017, http://manovich.net/index.php/projects/instagram-and-contemporary-image, Attribution-NonCommercial-NoDerivatives 4.0 International Creative Commons license, 148 págs.

MR Imaging-derived Oxygen-Hemoglobin Dissociation Curves and Fetal-Placental Oxygen-Hemoglobin Affinities.

Science.gov (United States)

Avni, Reut; Golani, Ofra; Akselrod-Ballin, Ayelet; Cohen, Yonni; Biton, Inbal; Garbow, Joel R; Neeman, Michal

2016-07-01

Purpose To generate magnetic resonance (MR) imaging-derived, oxygen-hemoglobin dissociation curves and to map fetal-placental oxygen-hemoglobin affinity in pregnant mice noninvasively by combining blood oxygen level-dependent (BOLD) T2* and oxygen-weighted T1 contrast mechanisms under different respiration challenges. Materials and Methods All procedures were approved by the Weizmann Institutional Animal Care and Use Committee. Pregnant mice were analyzed with MR imaging at 9.4 T on embryonic days 14.5 (eight dams and 58 fetuses; imprinting control region ICR strain) and 17.5 (21 dams and 158 fetuses) under respiration challenges ranging from hyperoxia to hypoxia (10 levels of oxygenation, 100%-10%; total imaging time, 100 minutes). A shorter protocol with normoxia to hyperoxia was also performed (five levels of oxygenation, 20%-100%; total imaging time, 60 minutes). Fast spin-echo anatomic images were obtained, followed by sequential acquisition of three-dimensional gradient-echo T2*- and T1-weighted images. Automated registration was applied to align regions of interest of the entire placenta, fetal liver, and maternal liver. Results were compared by using a two-tailed unpaired Student t test. R1 and R2* values were derived for each tissue. MR imaging-based oxygen-hemoglobin dissociation curves were constructed by nonlinear least square fitting of 1 minus the change in R2*divided by R2*at baseline as a function of R1 to a sigmoid-shaped curve. The apparent P50 (oxygen tension at which hemoglobin is 50% saturated) value was derived from the curves, calculated as the R1 scaled value (x) at which the change in R2* divided by R2*at baseline scaled (y) equals 0.5. Results The apparent P50 values were significantly lower in fetal liver than in maternal liver for both gestation stages (day 14.5: 21% ± 5 [P = .04] and day 17.5: 41% ± 7 [P hemoglobin dissociation curves with a shorter protocol that excluded the hypoxic periods was demonstrated. Conclusion MR imaging

MULTI-TEMPORAL CROP SURFACE MODELS COMBINED WITH THE RGB VEGETATION INDEX FROM UAV-BASED IMAGES FOR FORAGE MONITORING IN GRASSLAND

Directory of Open Access Journals (Sweden)

M. Possoch

2016-06-01

Full Text Available Remote sensing of crop biomass is important in regard to precision agriculture, which aims to improve nutrient use efficiency and to develop better stress and disease management. In this study, multi-temporal crop surface models (CSMs were generated from UAV-based dense imaging in order to derive plant height distribution and to determine forage mass. The low-cost UAV-based RGB imaging was carried out in a grassland experiment at the University of Bonn, Germany, in summer 2015. The test site comprised three consecutive growths including six different nitrogen fertilizer levels and three replicates, in sum 324 plots with a size of 1.5×1.5 m. Each growth consisted of six harvesting dates. RGB-images and biomass samples were taken at twelve dates nearly biweekly within two growths between June and September 2015. Images were taken with a DJI Phantom 2 in combination of a 2D Zenmuse gimbal and a GoPro Hero 3 (black edition. Overlapping images were captured in 13 to 16 m and overview images in approximately 60 m height at 2 frames per second. The RGB vegetation index (RGBVI was calculated as the normalized difference of the squared green reflectance and the product of blue and red reflectance from the non-calibrated images. The post processing was done with Agisoft PhotoScan Professional (SfM-based and Esri ArcGIS. 14 ground control points (GCPs were located in the field, distinguished by 30 cm × 30 cm markers and measured with a RTK-GPS (HiPer Pro Topcon with 0.01 m horizontal and vertical precision. The errors of the spatial resolution in x-, y-, z-direction were in a scale of 3-4 cm. From each survey, also one distortion corrected image was georeferenced by the same GCPs and used for the RGBVI calculation. The results have been used to analyse and evaluate the relationship between estimated plant height derived with this low-cost UAV-system and forage mass. Results indicate that the plant height seems to be a suitable indicator for forage mass

Multi-Temporal Crop Surface Models Combined with the RGB Vegetation Index from Uav-Based Images for Forage Monitoring in Grassland

Science.gov (United States)

Possoch, M.; Bieker, S.; Hoffmeister, D.; Bolten, A.; Schellberg, J.; Bareth, G.

2016-06-01

Remote sensing of crop biomass is important in regard to precision agriculture, which aims to improve nutrient use efficiency and to develop better stress and disease management. In this study, multi-temporal crop surface models (CSMs) were generated from UAV-based dense imaging in order to derive plant height distribution and to determine forage mass. The low-cost UAV-based RGB imaging was carried out in a grassland experiment at the University of Bonn, Germany, in summer 2015. The test site comprised three consecutive growths including six different nitrogen fertilizer levels and three replicates, in sum 324 plots with a size of 1.5×1.5 m. Each growth consisted of six harvesting dates. RGB-images and biomass samples were taken at twelve dates nearly biweekly within two growths between June and September 2015. Images were taken with a DJI Phantom 2 in combination of a 2D Zenmuse gimbal and a GoPro Hero 3 (black edition). Overlapping images were captured in 13 to 16 m and overview images in approximately 60 m height at 2 frames per second. The RGB vegetation index (RGBVI) was calculated as the normalized difference of the squared green reflectance and the product of blue and red reflectance from the non-calibrated images. The post processing was done with Agisoft PhotoScan Professional (SfM-based) and Esri ArcGIS. 14 ground control points (GCPs) were located in the field, distinguished by 30 cm × 30 cm markers and measured with a RTK-GPS (HiPer Pro Topcon) with 0.01 m horizontal and vertical precision. The errors of the spatial resolution in x-, y-, z-direction were in a scale of 3-4 cm. From each survey, also one distortion corrected image was georeferenced by the same GCPs and used for the RGBVI calculation. The results have been used to analyse and evaluate the relationship between estimated plant height derived with this low-cost UAV-system and forage mass. Results indicate that the plant height seems to be a suitable indicator for forage mass. There is a

Pixel-wise derivation of pulmonary regurgitation index could influence clinical decision: A phase-contrast MR imaging study on patients with repaired tetralogy of Fallot.

Science.gov (United States)

Wu, Pei-Hsin; Chung, Hsiao-Wen; Wu, Ming-Ting; Ko, Cheng-Wen

2017-08-01

Regurgitant fraction (RF) measured from 2D phase-contrast MRI has been used as a standard to quantitate the degree of pulmonary regurgitation and serves as a determinant indicator of prognosis for tetralogy of Fallot after surgical repair. This study demonstrated the potential underestimate of RF using the conventional definition and its impact on clinical decision when backward flow occurred during systolic periods. Quantitative flow parameters, including forward flow volume (FFV), backward flow volume (BFV), and RF were estimated by two approaches: One derived from conventional ROI-averaged curve (bulk quantity) and the other in a pixel-wise manner to spatially reflect inhomogeneous flow profile (pixel-wise quantity). Eccentricity at systolic peak (Ecc sys ) was adopted as an index reflecting spatial flow inhomogeneity. Flow parameters derived from ROI-averaged curves on main pulmonary artery were significantly smaller than that of pixel-wise measurement (P 0.3 appears greater compared to the group with Ecc sys < 0.3. Thirteen out of 68 RF values (19%) were underrated while using bulk analysis. The spatial-related flow parameters showed more consistency with the qualitative flow profile pattern for pulmonary arteries, and could be a decisive complement for diagnostic classification. Copyright © 2017 Elsevier B.V. All rights reserved.

Digital processing of SEM images for the assessment of evaluation indexes of cleaning interventions on Pentelic marble surfaces

International Nuclear Information System (INIS)

Moropoulou, A.; Delegou, E.T.; Vlahakis, V.; Karaviti, E.

2007-01-01

In this work, digital processing of scanning-electron-microscopy images utilized to assess cleaning interventions applied on the Pentelic marble surfaces of the National Archaeological Museum and National Library in Athens, Greece. Beside mineralogical and chemical characterization that took place by scanning-electron-microscopy with Energy Dispersive X-ray Spectroscopy, the image-analysis program EDGE was applied for estimating three evaluation indexes of the marble micro-structure. The EDGE program was developed by the U.S. Geological Survey for the evaluation of cleaning interventions applied on Philadelphia City Hall. This computer program analyzes scanning-electron-microscopy images of stone specimens cut in cross-section for measuring the fractal dimension of the exposed surfaces, the stone near-surface fracture density, the shape factor (a surface roughness factor) and the friability index which represents the physico-chemical and physico-mechanical stability of the stone surface. The results indicated that the evaluation of the marble surface micro-structure before and after cleaning is achieved by the suggested indexes, while the performance of cleaning interventions on the marble surfaces can be assessed

Stylized facts in internal rates of return on stock index and its derivative transactions

Science.gov (United States)

Pichl, Lukáš; Kaizoji, Taisei; Yamano, Takuya

2007-08-01

Universal features in stock markets and their derivative markets are studied by means of probability distributions in internal rates of return on buy and sell transaction pairs. Unlike the stylized facts in normalized log returns, the probability distributions for such single asset encounters incorporate the time factor by means of the internal rate of return, defined as the continuous compound interest. Resulting stylized facts are shown in the probability distributions derived from the daily series of TOPIX, S & P 500 and FTSE 100 index close values. The application of the above analysis to minute-tick data of NIKKEI 225 and its futures market, respectively, reveals an interesting difference in the behavior of the two probability distributions, in case a threshold on the minimal duration of the long position is imposed. It is therefore suggested that the probability distributions of the internal rates of return could be used for causality mining between the underlying and derivative stock markets. The highly specific discrete spectrum, which results from noise trader strategies as opposed to the smooth distributions observed for fundamentalist strategies in single encounter transactions may be useful in deducing the type of investment strategy from trading revenues of small portfolio investors.

Phenotypic feature quantification of patient derived 3D cancer spheroids in fluorescence microscopy image

Science.gov (United States)

Kang, Mi-Sun; Rhee, Seon-Min; Seo, Ji-Hyun; Kim, Myoung-Hee

2017-03-01

Patients' responses to a drug differ at the cellular level. Here, we present an image-based cell phenotypic feature quantification method for predicting the responses of patient-derived glioblastoma cells to a particular drug. We used high-content imaging to understand the features of patient-derived cancer cells. A 3D spheroid culture formation resembles the in vivo environment more closely than 2D adherent cultures do, and it allows for the observation of cellular aggregate characteristics. However, cell analysis at the individual level is more challenging. In this paper, we demonstrate image-based phenotypic screening of the nuclei of patient-derived cancer cells. We first stitched the images of each well of the 384-well plate with the same state. We then used intensity information to detect the colonies. The nuclear intensity and morphological characteristics were used for the segmentation of individual nuclei. Next, we calculated the position of each nucleus that is appeal of the spatial pattern of cells in the well environment. Finally, we compared the results obtained using 3D spheroid culture cells with those obtained using 2D adherent culture cells from the same patient being treated with the same drugs. This technique could be applied for image-based phenotypic screening of cells to determine the patient's response to the drug.

Right ventricular function in asthmatic children determined with PW-TDI

International Nuclear Information System (INIS)

Wang Shaona; Song Lili; Cong Lin; Li Liping; Huang Yanxia

2007-01-01

Objective: To assess the right ventricular function of asthmatic children in onset period or remission period by using PW-TDI. Method: 36 children with confirmed asthma were enrolled. In tricuspid annular, the ECHO were recorded with PW-PDI pattern to obtain fight ventricular function (Sm, e-peak, Vmax for a-peak, and e/a), ICT, ET, IRT and Tei-Index. These were carried out in acute attack period and stable period. Result: Right ventficular function parameter (Sm, Vmax for e-peak, Vmax for a-peak, e/a and Tei-Index) in acute attack period were significant different compared to those in stable period (P<0.05). Conclusions: The fight ventricular function was impaired in patients with asthma in acute attack period. PW-TDI is helpful for assessing right ventricular function to asthmatic children. (authors)

Echocardiographic assessment of fetal left ventricular function in hypertensive disorder of pregnancy

International Nuclear Information System (INIS)

Liu Xiaozhen; Liu Shaozhong

2011-01-01

Objective: To investigate fetal left ventricular function in hypertensive disorder of pregnancy (HDP). Methods: Fetuses of hypertensive (84) and normotensive (147) mothers were enrolled in this study. The fetal left ventricular ejection fractions, E/A ratios of mitral valves, left atrial shortening fractions and Tei indexes of the two groups were measured on fetal echocardiography. Results: The left ventricular ejection fractions (P=0.040), E/A ratios of the mitral valves (P=0.042) and the left atrial shortening fractions (P=0.036) in fetuses of HDP were significantly smaller than those of the normal group whereas the Tei indexes (P=0.030) were significantly larger than those of the normal group. Conclusion: The hypertensive disorder of pregnancy may cause decreased systolic, diastolic and global function of the fetal left ventricle. (authors)

Refractive Index Imaging of Cells with Variable-Angle Near-Total Internal Reflection (TIR) Microscopy.

Science.gov (United States)

Bohannon, Kevin P; Holz, Ronald W; Axelrod, Daniel

2017-10-01

The refractive index in the interior of single cells affects the evanescent field depth in quantitative studies using total internal reflection (TIR) fluorescence, but often that index is not well known. We here present method to measure and spatially map the absolute index of refraction in a microscopic sample, by imaging a collimated light beam reflected from the substrate/buffer/cell interference at variable angles of incidence. Above the TIR critical angle (which is a strong function of refractive index), the reflection is 100%, but in the immediate sub-critical angle zone, the reflection intensity is a very strong ascending function of incidence angle. By analyzing the angular position of that edge at each location in the field of view, the local refractive index can be estimated. In addition, by analyzing the steepness of the edge, the distance-to-substrate can be determined. We apply the technique to liquid calibration samples, silica beads, cultured Chinese hamster ovary cells, and primary culture chromaffin cells. The optical technique suffers from decremented lateral resolution, scattering, and interference artifacts. However, it still provides reasonable results for both refractive index (~1.38) and for distance-to-substrate (~150 nm) for the cells, as well as a lateral resolution to about 1 µm.

Single-image phase retrieval using an edge illumination X-ray phase-contrast imaging setup

Energy Technology Data Exchange (ETDEWEB)

Diemoz, Paul C., E-mail: p.diemoz@ucl.ac.uk; Vittoria, Fabio A. [University College London, London WC1 E6BT (United Kingdom); Research Complex at Harwell, Oxford Harwell Campus, Didcot OX11 0FA (United Kingdom); Hagen, Charlotte K.; Endrizzi, Marco [University College London, London WC1 E6BT (United Kingdom); Coan, Paola [Ludwig-Maximilians-University, Munich 81377 (Germany); Ludwig-Maximilians-University, Garching 85748 (Germany); Brun, Emmanuel [Ludwig-Maximilians-University, Garching 85748 (Germany); European Synchrotron Radiation Facility, Grenoble 38043 (France); Wagner, Ulrich H.; Rau, Christoph [Diamond Light Source, Harwell Oxford Campus, Didcot OX11 0DE (United Kingdom); Robinson, Ian K. [Research Complex at Harwell, Oxford Harwell Campus, Didcot OX11 0FA (United Kingdom); London Centre for Nanotechnology, London WC1 H0AH (United Kingdom); Bravin, Alberto [European Synchrotron Radiation Facility, Grenoble 38043 (France); Olivo, Alessandro [University College London, London WC1 E6BT (United Kingdom); Research Complex at Harwell, Oxford Harwell Campus, Didcot OX11 0FA (United Kingdom)

2015-06-25

A method enabling the retrieval of thickness or projected electron density of a sample from a single input image is derived theoretically and successfully demonstrated on experimental data. A method is proposed which enables the retrieval of the thickness or of the projected electron density of a sample from a single input image acquired with an edge illumination phase-contrast imaging setup. The method assumes the case of a quasi-homogeneous sample, i.e. a sample with a constant ratio between the real and imaginary parts of its complex refractive index. Compared with current methods based on combining two edge illumination images acquired in different configurations of the setup, this new approach presents advantages in terms of simplicity of acquisition procedure and shorter data collection time, which are very important especially for applications such as computed tomography and dynamical imaging. Furthermore, the fact that phase information is directly extracted, instead of its derivative, can enable a simpler image interpretation and be beneficial for subsequent processing such as segmentation. The method is first theoretically derived and its conditions of applicability defined. Quantitative accuracy in the case of homogeneous objects as well as enhanced image quality for the imaging of complex biological samples are demonstrated through experiments at two synchrotron radiation facilities. The large range of applicability, the robustness against noise and the need for only one input image suggest a high potential for investigations in various research subjects.

Indexing amyloid peptide diffraction from serial femtosecond crystallography: new algorithms for sparse patterns

Energy Technology Data Exchange (ETDEWEB)

Brewster, Aaron S. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Sawaya, Michael R. [University of California, Los Angeles, CA 90095-1570 (United States); University of California, Los Angeles, CA 90095-1570 (United States); University of California, Los Angeles, CA 90095-1570 (United States); Rodriguez, Jose [University of California, Los Angeles, CA 90095-1570 (United States); University of California, Los Angeles, CA 90095-1570 (United States); Hattne, Johan; Echols, Nathaniel [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); McFarlane, Heather T. [University of California, Los Angeles, CA 90095-1570 (United States); University of California, Los Angeles, CA 90095-1570 (United States); Cascio, Duilio [University of California, Los Angeles, CA 90095-1570 (United States); University of California, Los Angeles, CA 90095-1570 (United States); University of California, Los Angeles, CA 90095-1570 (United States); Adams, Paul D. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); University of California, Berkeley, CA 94720 (United States); Eisenberg, David S. [University of California, Los Angeles, CA 90095-1570 (United States); University of California, Los Angeles, CA 90095-1570 (United States); University of California, Los Angeles, CA 90095-1570 (United States); Sauter, Nicholas K., E-mail: nksauter@lbl.gov [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

2015-02-01

Special methods are required to interpret sparse diffraction patterns collected from peptide crystals at X-ray free-electron lasers. Bragg spots can be indexed from composite-image powder rings, with crystal orientations then deduced from a very limited number of spot positions. Still diffraction patterns from peptide nanocrystals with small unit cells are challenging to index using conventional methods owing to the limited number of spots and the lack of crystal orientation information for individual images. New indexing algorithms have been developed as part of the Computational Crystallography Toolbox (cctbx) to overcome these challenges. Accurate unit-cell information derived from an aggregate data set from thousands of diffraction patterns can be used to determine a crystal orientation matrix for individual images with as few as five reflections. These algorithms are potentially applicable not only to amyloid peptides but also to any set of diffraction patterns with sparse properties, such as low-resolution virus structures or high-throughput screening of still images captured by raster-scanning at synchrotron sources. As a proof of concept for this technique, successful integration of X-ray free-electron laser (XFEL) data to 2.5 Å resolution for the amyloid segment GNNQQNY from the Sup35 yeast prion is presented.

Satellite image analysis and a hybrid ESSS/ANN model to forecast solar irradiance in the tropics

International Nuclear Information System (INIS)

Dong, Zibo; Yang, Dazhi; Reindl, Thomas; Walsh, Wilfred M.

2014-01-01

Highlights: • Satellite image analysis is performed and cloud cover index is classified using self-organizing maps (SOM). • The ESSS model is used to forecast cloud cover index. • Solar irradiance is estimated using multi-layer perceptron (MLP). • The proposed model shows better accuracy than other investigated models. - Abstract: We forecast hourly solar irradiance time series using satellite image analysis and a hybrid exponential smoothing state space (ESSS) model together with artificial neural networks (ANN). Since cloud cover is the major factor affecting solar irradiance, cloud detection and classification are crucial to forecast solar irradiance. Geostationary satellite images provide cloud information, allowing a cloud cover index to be derived and analysed using self-organizing maps (SOM). Owing to the stochastic nature of cloud generation in tropical regions, the ESSS model is used to forecast cloud cover index. Among different models applied in ANN, we favour the multi-layer perceptron (MLP) to derive solar irradiance based on the cloud cover index. This hybrid model has been used to forecast hourly solar irradiance in Singapore and the technique is found to outperform traditional forecasting models

Combining MRI with PET for partial volume correction improves image-derived input functions in mice

Energy Technology Data Exchange (ETDEWEB)

Evans, Eleanor; Buonincontri, Guido [Wolfson Brain Imaging Centre, University of Cambridge, Cambridge (United Kingdom); Izquierdo, David [Athinoula A Martinos Centre, Harvard University, Cambridge, MA (United States); Methner, Carmen [Department of Medicine, University of Cambridge, Cambridge (United Kingdom); Hawkes, Rob C [Wolfson Brain Imaging Centre, University of Cambridge, Cambridge (United Kingdom); Ansorge, Richard E [Department of Physics, University of Cambridge, Cambridge (United Kingdom); Kreig, Thomas [Department of Medicine, University of Cambridge, Cambridge (United Kingdom); Carpenter, T Adrian [Wolfson Brain Imaging Centre, University of Cambridge, Cambridge (United Kingdom); Sawiak, Stephen J [Wolfson Brain Imaging Centre, University of Cambridge, Cambridge (United Kingdom); Behavioural and Clinical Neurosciences Institute, University of Cambridge, Cambridge (United Kingdom)

2014-07-29

Kinetic modelling in PET requires the arterial input function (AIF), defined as the time-activity curve (TAC) in plasma. This measure is challenging to obtain in mice due to low blood volumes, resulting in a reliance on image-based methods for AIF derivation. We present a comparison of PET- and MR-based region-of-interest (ROI) analysis to obtain image-derived AIFs from the left ventricle (LV) of a mouse model. ROI-based partial volume correction (PVC) was performed to improve quantification.

Combining MRI with PET for partial volume correction improves image-derived input functions in mice

International Nuclear Information System (INIS)

Evans, Eleanor; Buonincontri, Guido; Izquierdo, David; Methner, Carmen; Hawkes, Rob C; Ansorge, Richard E; Kreig, Thomas; Carpenter, T Adrian; Sawiak, Stephen J

2014-01-01

Kinetic modelling in PET requires the arterial input function (AIF), defined as the time-activity curve (TAC) in plasma. This measure is challenging to obtain in mice due to low blood volumes, resulting in a reliance on image-based methods for AIF derivation. We present a comparison of PET- and MR-based region-of-interest (ROI) analysis to obtain image-derived AIFs from the left ventricle (LV) of a mouse model. ROI-based partial volume correction (PVC) was performed to improve quantification.

COMPOSTOS ORGÂNICOS VOLÁTEIS DE TINTAS IMOBILIÁRIAS E CERTIFICAÇÕES AMBIENTAIS: ESTUDO DE CASO PARA SUBSOLOS

Directory of Open Access Journals (Sweden)

Henrique Oliveira Merten

2016-11-01

Full Text Available RESUMO: Compostos orgânicos voláteis são poluentes atmosféricos capazes de provocar uma série de danos à saúde dos seres humanos, o que mostra a importância do seu estudo. Apesar disto, as legislações e certificações ambientais vigentes no mundo e no Brasil apresentam parâmetros muitas vezes ineficientes em relação a esses contaminantes. Neste contexto, o presente trabalho teve como objetivo a avaliação das legislações e certificações ambientais nacionais e internacionais em relação ao critério de concentração de compostos orgânicos voláteis (COVs em ambientes internos. Para tanto, foi apresentada uma avaliação simplificada da concentração de COVs emitidos por tintas imobiliárias nos subsolos de um edifício em Brasília, a fim de embasar a análise realizada. A principal contribuição deste trabalho foi apresentar a quantificação de COVs para o estudo de caso analisado, as lacunas presentes nas certificações e legislações ambientais com relação aos COVs, ressaltando os pontos que precisam ser melhorados na legislação para a minimização dos impactos à saúde causados por esses compostos. ABSTRACT: Volatile organic compounds are air pollutants that can cause a lot of damage to human health, which shows the importance of their study. Despite this, laws and environmental certifications in the world and Brazil have parameters often inefficient in relation to these contaminants. In this context, this study aimed to evaluate the legislation and national and international environmental certifications for the criterion of concentration of volatile organic compounds (VOCs in indoor environments. Therefore, it was presented a simplified evaluation of VOC concentration emitted by housing paints in the basement of a building in Brasilia, in order to base this analysis. The main contribution of this paper was to present the quantification of VOCs for the analyzed case study, the gaps present in certifications

Erythrocyte-derived nano-probes functionalized with antibodies for targeted near infrared fluorescence imaging of cancer cells

OpenAIRE

Anvari, Bahman; Mac, Jenny T.; Nunez, Vicente; Burns, Joshua M.; Guerrero, Yadir A.

2016-01-01

Constructs derived from mammalian cells are emerging as a new generation of nano-scale platforms for clinical imaging applications. Herein, we report successful engineering of hybrid nano-structures composed of erythrocyte-derived membranes doped with FDA-approved near infrared (NIR) chromophore, indocyanine green (ICG), and surface-functionalized with antibodies to achieve molecular targeting. We demonstrate that these constructs can be used for targeted imaging of cancer cells in vitro. The...

The Children's Body Image Scale: reliability and use with international standards for body mass index.

Science.gov (United States)

Truby, Helen; Paxton, Susan J

2008-03-01

To test the reliability of the Children's Body Image Scale (CBIS) and assess its usefulness in the context of new body size charts for children. Participants were 281 primary schoolchildren with 50% being retested after 3 weeks. The CBIS figure scale was compared with a range of international body mass index (BMI) reference standards. Children had a high degree of body image dissatisfaction. The test-retest reliability of the CBIS was supported. The CBIS is a useful tool for assessing body image in children with sound scale properties. It can also be used to identify the body size of children, which lies outside the healthy weight range of BMI.

Iron zircon pigment synthesis: Proposal of a mixing index for the raw materials mixtures

International Nuclear Information System (INIS)

Zumaquero, E.; Ortsb, M.J.; Sanz, V.; Mestre, S.

2017-01-01

Iron zircon coral pigments are very interesting from an industrial point of view because of their high colouring power and their stability at high temperatures. However, the pigment's synthesis is particularly troublesome due to its specific reaction mechanism. As an encapsulated pigment it becomes very important how the raw materials are distributed in the reaction mixture. To evaluate the effectiveness of the mixing process, it would be convenient to define a parameter, that is the mixing index, to estimate the degree of homogeneity of the system. In the current investigation, a mixing index is proposed derived from the power spectrum of Fourier transform of scanning electron microscope (SEM) images of the raw material mixture. Concretely, the number of pixels in a certain range of values in the image of the power spectrum, seems to behave relatively well as mixing index. This index allows us to distinguish between samples with different zirconia and iron oxide used as precursors. The proposed mixing index seems to be related to the colouring power of the final pigment when the synthesis generates enough zircon to encapsulate hematite particles. [es

Validation of an image quality index: its correlation with quality control parameters

International Nuclear Information System (INIS)

Cabrejas, M.L.C.; Giannone, C.A.; Arashiro, J.G.; Cabrejas, R.C.

2002-01-01

Objective and Rationale: To validate a new image quality index (the Performance Index: PI) that assesses detectability of simulated lesions with a phantom. This index, presumably must depend markedly on quality control (QC) parameters as tomographic uniformity (Unif), Centre of Rotation (COR) and Spatial resolution (FWHM). The simultaneous effects of the QC parameters may explain much of the variation in the PIs; i.e. they may be predictors of the PI values. Methods: An overall performance phantom containing 3 sections was used. The first uniform section was used to determine tomographic uniformity. From the analysis of the slices corresponding to the second section containing 8 cold cylindrical simulated lesions of different diameters (range 7 mm - 17 mm), the number of true and false positives are determined and from these a new Performance Index (PI) is defined as the ratio between the positive predictive value and the sensitivity (expressed as its complement adding a constant to avoid a singularity). A point source located on the top of the phantom was used to determine the Centre of Rotation and the Spatial Resolution expressed by the FWHM in mm. 40 nuclear medicine labs participate at the survey. Standard multiple regression analysis between the Performance Index, as dependent variable, and FWHM, COR and Unif as independent variables was performed to evaluate the influence of the QC parameters on the PI values. Results: It is shown that resolution and COR are both predictors of the PIs, with statistical significance for the multiple correlation co-efficient R. However the addition of the variable tomographic uniformity to the model, does not improve the prediction of PIs. Moreover, the regression model lacks overall statistical significance. Regression summary for dependent variable Performance Index is presented. Conclusions: We confirm that the new Performance Index (PI), depends on QC parameters as COR and Spatial resolution. Those labs whose PIs are out

Rapid Automatic Lighting Control of a Mixed Light Source for Image Acquisition using Derivative Optimum Search Methods

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Kim HyungTae

2015-01-01

Full Text Available Automatic lighting (auto-lighting is a function that maximizes the image quality of a vision inspection system by adjusting the light intensity and color.In most inspection systems, a single color light source is used, and an equal step search is employed to determine the maximum image quality. However, when a mixed light source is used, the number of iterations becomes large, and therefore, a rapid search method must be applied to reduce their number. Derivative optimum search methods follow the tangential direction of a function and are usually faster than other methods. In this study, multi-dimensional forms of derivative optimum search methods are applied to obtain the maximum image quality considering a mixed-light source. The auto-lighting algorithms were derived from the steepest descent and conjugate gradient methods, which have N-size inputs of driving voltage and one output of image quality. Experiments in which the proposed algorithm was applied to semiconductor patterns showed that a reduced number of iterations is required to determine the locally maximized image quality.

Refractive index sensing of green fluorescent proteins in living cells using fluorescence lifetime imaging microscopy

NARCIS (Netherlands)

van Manen, Henk-Jan; Verkuijlen, Paul; Wittendorp, Paul; Subramaniam, Vinod; van den Berg, Timo K; Roos, Dirk; Otto, Cees

2008-01-01

We show that fluorescence lifetime imaging microscopy (FLIM) of green fluorescent protein (GFP) molecules in cells can be used to report on the local refractive index of intracellular GFP. We expressed GFP fusion constructs of Rac2 and gp91(phox), which are both subunits of the phagocyte NADPH

Comparison of satellite-derived LAI and precipitation anomalies over Brazil with a thermal infrared-based Evaporative Stress Index for 2003-2013

Science.gov (United States)

Anderson, Martha C.; Zolin, Cornelio A.; Hain, Christopher R.; Semmens, Kathryn; Tugrul Yilmaz, M.; Gao, Feng

2015-07-01

Shortwave vegetation index (VI) and leaf area index (LAI) remote sensing products yield inconsistent depictions of biophysical response to drought and pluvial events that have occurred in Brazil over the past decade. Conflicting reports of severity of drought impacts on vegetation health and functioning have been attributed to cloud and aerosol contamination of shortwave reflectance composites, particularly over the rainforested regions of the Amazon basin which are subject to prolonged periods of cloud cover and episodes of intense biomass burning. This study compares timeseries of satellite-derived maps of LAI from the Moderate Resolution Imaging Spectroradiometer (MODIS) and precipitation from the Tropical Rainfall Mapping Mission (TRMM) with a diagnostic Evaporative Stress Index (ESI) retrieved using thermal infrared remote sensing over South America for the period 2003-2013. This period includes several severe droughts and floods that occurred both over the Amazon and over unforested savanna and agricultural areas in Brazil. Cross-correlations between absolute values and standardized anomalies in monthly LAI and precipitation composites as well as the actual-to-reference evapotranspiration (ET) ratio used in the ESI were computed for representative forested and agricultural regions. The correlation analyses reveal strong apparent anticorrelation between MODIS LAI and TRMM precipitation anomalies over the Amazon, but better coupling over regions vegetated with shorter grass and crop canopies. The ESI was more consistently correlated with precipitation patterns over both landcover types. Temporal comparisons between ESI and TRMM anomalies suggest longer moisture buffering timescales in the deeper rooted rainforest systems. Diagnostic thermal-based retrievals of ET and ET anomalies, such as used in the ESI, provide independent information on the impacts of extreme hydrologic events on vegetation health in comparison with VI and precipitation-based drought

Female body dissatisfaction after exposure to overweight and thin media images : The role of body mass index and neuroticism

NARCIS (Netherlands)

Dalley, Simon E.; Buunk, Abraham P.; Umit, Turul

Exposure to thin media images is thought to play a significant role in the development of body image dissatisfaction (BID) amongst females. In this study we examined whether individual differences in body mass index (BMI) and neuroticism can make females more vulnerable to BID upon exposure to

An effect of left ventricular hypertrophy on mild-to-moderate left ventricular diastolic dysfunction

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Sharma Kattel, MD

2016-03-01

Conclusions: In mild-to-moderate LVDD patients, both FP and the Tei index were significantly higher when LVH was present. This may suggest LVH as a possible predictor for the future development of severe LVDD and diastolic heart failure.

Five-membered heterocycles. Part II. Crystal structures and HOMA index calculations for selected 1,3,4-thiadiazole derivatives

Science.gov (United States)

Mrozek, A.; Karolak-Wojciechowska, J.; Amiel, P.; Barbe, J.

2000-06-01

Crystal structures of four bisubstituted 1,3,4-thiadiazole derivatives were determined. Detailed description of the five-membered heteroring geometry is enabled thorough analysis of ring aromaticity. For this purpose the HOMA index was used as a quantitative measure of aromaticity. The calculated HOMA indices evidenced the role of substituents. In particular, increase in the substituent electrophilicity brings about increase in aromaticity.

Characteristics of equatorial gravity waves derived from mesospheric airglow imaging observations

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S. Suzuki

2009-04-01

Full Text Available We present the characteristics of small-scale (<100 km gravity waves in the equatorial mesopause region derived from OH airglow imaging observations at Kototabang (100.3° E, 0.2° S, Indonesia, from 2002 to 2005. We adopted a method that could automatically detect gravity waves in the airglow images using two-dimensional cross power spectra of gravity waves. The propagation directions of the waves were likely controlled by zonal filtering due to stratospheric mean winds that show a quasi-biennial oscillation (QBO and the presence of many wave sources in the troposphere.

FELIX: an algorithm for indexing multiple crystallites in X-ray free-electron laser snapshot diffraction images

DEFF Research Database (Denmark)

Beyerlein, Kenneth R.; White, Thomas A.; Yefanov, Oleksandr

2017-01-01

A novel algorithm for indexing multiple crystals in snapshot X-ray diffraction images, especially suited for serial crystallography data, is presented. The algorithm, FELIX, utilizes a generalized parametrization of the Rodrigues-Frank space, in which all crystal systems can be represented without...

Multifunctional PHPMA-Derived Polymer for Ratiometric pH Sensing, Fluorescence Imaging, and Magnetic Resonance Imaging.

Science.gov (United States)

Su, Fengyu; Agarwal, Shubhangi; Pan, Tingting; Qiao, Yuan; Zhang, Liqiang; Shi, Zhengwei; Kong, Xiangxing; Day, Kevin; Chen, Meiwan; Meldrum, Deirdre; Kodibagkar, Vikram D; Tian, Yanqing

2018-01-17

In this paper, we report synthesis and characterization of a novel multimodality (MRI/fluorescence) probe for pH sensing and imaging. A multifunctional polymer was derived from poly(N-(2-hydroxypropyl)methacrylamide) (PHPMA) and integrated with a naphthalimide-based-ratiometric fluorescence probe and a gadolinium-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid complex (Gd-DOTA complex). The polymer was characterized using UV-vis absorption spectrophotometry, fluorescence spectrofluorophotometry, magnetic resonance imaging (MRI), and confocal microscopy for optical and MRI-based pH sensing and cellular imaging. In vitro labeling of macrophage J774 and esophageal CP-A cell lines shows the polymer's ability to be internalized in the cells. The transverse relaxation time (T 2 ) of the polymer was observed to be pH-dependent, whereas the spin-lattice relaxation time (T 1 ) was not. The pH probe in the polymer shows a strong fluorescence-based ratiometric pH response with emission window changes, exhibiting blue emission under acidic conditions and green emission under basic conditions, respectively. This study provides new materials with multimodalities for pH sensing and imaging.

Volatile profile of heated soybean oil treated with quercetin and chlorogenic acid Perfil de compostos voláteis do óleo de soja aquecido e tratado com quercetina e ácido clorogênico

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Adriana Leão de Miranda

2008-12-01

Full Text Available Changes in the profile of volatile compounds after the heating of refined soybean oil without adding antioxidants, and treated with quercetin and chlorogenic acid (5-CQA were investigated by GC/FID, GC/MS, and GC/SNIFFING. The heating temperature of the oil sample was 20 °C for the first minute, and then it was increased up to 160 °C at the rate of 10 °C min-1. The final temperature was kept for 10 minutes. 19 volatiles were identified in the heated samples without antioxidants. Medium-chain carbonyls predominated in the volatile fraction, mainly 2-heptenal, 2,4-heptadienal and 2,4-decadienal. Around 11 to 15 volatile compounds were detected in the heated samples treated with 5-CQA and quercetin, respectively. 5-CQA was not very efficient in delaying the formation of oxidative volatile compounds. The samples quercetin presented lower proportion of carbonyls with C6-C9.. The GC peak area data were used as an approach to estimate the relative content of each volatile compound and indicate that the samples treated with quercetin (p As alterações no perfil de compostos voláteis, após o aquecimento de óleo de soja refinado sem a adição de antioxidantes e tratado previamente com quercetina e ácido clorogênico (5-ACQ, foram investigadas através da CG/DIC, CG/EM e CG/SNIFFING. A temperatura de aquecimento do óleo foi de 20 °C no primeiro minuto e aumentada até 160 °C à taxa de 10 °C min-1. A temperatura final foi mantida por 10 minutos. Um total de 19 compostos voláteis foi identificado nas amostras aquecidas sem a adição de antioxidantes. As carbonilas de cadeia média predominaram na fração volátil. Cerca de 15 e 11 compostos voláteis foram detectados no óleo aquecido com adição prévia de quercetina e 5-ACQ, respectivamente. As amostras tratadas com quercetina mostraram uma menor proporção de carbonilas com esqueletos de carbono C6-C9. A composição estimada de compostos voláteis mostrou que amostras tratadas com

Diethylenetriaminepentaacetic acid-gadolinium (DTPA-Gd)-conjugated polysuccinimide derivatives as magnetic resonance imaging contrast agents.

Science.gov (United States)

Lee, Ha Young; Jee, Hye Won; Seo, Sung Mi; Kwak, Byung Kook; Khang, Gilson; Cho, Sun Hang

2006-01-01

Biocompatible polysuccinimide (PSI) derivatives conjugated with diethylenetriaminepentaacetic acid gadolinium (DTPA-Gd) were prepared as magnetic resonance imaging (MRI) contrast agents. In this study, we synthesized PSI derivatives incorporating methoxy-poly(ethylene glycol) (mPEG) as hydrophilic ligand, hexadecylamine as hydrophobic ligand, and DTPA-Gd as contrast agent. PSI was synthesized by the polycondensation polymerization of aspartic acid. All the synthesized materials were characterized by proton nuclear magnetic resonance (1H NMR). Critical micellization concentrations were determined using fluorescent probes (pyrene). Micelle size and shape were measured by electro-photometer light scattering (ELS) and atomic force microscopy (AFM). The formed micelle size ranged from 100 to 300 nm. The T1-weighted MR images of the phantom prepared with PSI-mPEG-C16-(DTPA-Gd) were obtained in a 3.0 T clinical MR imager, and the conjugates showed a great potential as MRI contrast agents.

County-Scale Spatial Distribution of Soil Enzyme Activities and Enzyme Activity Indices in Agricultural Land: Implications for Soil Quality Assessment

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Xiangping Tan

2014-01-01

Full Text Available Here the spatial distribution of soil enzymatic properties in agricultural land was evaluated on a county-wide (567 km2 scale in Changwu, Shaanxi Province, China. The spatial variations in activities of five hydrolytic enzymes were examined using geostatistical methods. The relationships between soil enzyme activities and other soil properties were evaluated using both an integrated total enzyme activity index (TEI and the geometric mean of enzyme activities (GME. At the county scale, soil invertase, phosphatase, and catalase activities were moderately spatially correlated, whereas urease and dehydrogenase activities were weakly spatially correlated. Correlation analysis showed that both TEI and GME were better correlated with selected soil physicochemical properties than single enzyme activities. Multivariate regression analysis showed that soil OM content had the strongest positive effect while soil pH had a negative effect on the two enzyme activity indices. In addition, total phosphorous content had a positive effect on TEI and GME in orchard soils, whereas alkali-hydrolyzable nitrogen and available potassium contents, respectively, had negative and positive effects on these two enzyme indices in cropland soils. The results indicate that land use changes strongly affect soil enzyme activities in agricultural land, where TEI provides a sensitive biological indicator for soil quality.

Relationship between LiDAR-derived forest canopy height and Landsat images

Science.gov (United States)

Cristina Pascual; Antonio Garcia-Abril; Warren B. Cohen; Susana. Martin-Fernandez

2010-01-01

The mean and standard deviation (SD) of light detection and ranging (LiDAR)-derived canopy height are related to forest structure. However, LiDAR data typically cover a limited area and have a high economic cost compared with satellite optical imagery. Optical images may be required to extrapolate LiDAR height measurements across a broad landscape. Different spectral...

Properties of the water column and bottom derived from Airborne Visible Infrared Imaging Spectrometer (AVIRIS) data

Science.gov (United States)

Lee, Zhongping; Carder, Kendall L.; Chen, Robert F.; Peacock, Thomas G.

2001-06-01

Using Airborne Visible Infrared Imaging Spectrometer (AVIRIS) data as an example, we show in this study that the properties of the water column and bottom of a large, shallow area can be adequately retrieved using a model-driven optimization technique. The simultaneously derived properties include bottom depth, bottom albedo, and water absorption and backscattering coefficients, which in turn could be used to derive concentrations of chlorophyll, dissolved organic matter, and suspended sediments in the water column. The derived bottom depths were compared with a bathymetry chart and a boat survey and were found to agree very well. Also, the derived bottom albedo image shows clear spatial patterns, with end-members consistent with sand and seagrass. The image of absorption and backscattering coefficients indicates that the water is quite horizontally mixed. Without bottom corrections, chlorophyll a retrievals were ˜50 mg m-3, while the retrievals after bottom corrections were tenfold less, approximating real values. These results suggest that the model and approach used work very well for the retrieval of subsurface properties of shallow-water environments even for rather turbid environments like Tampa Bay, Florida.

Individual Factors Affecting Self-esteem, and Relationships Among Self-esteem, Body Mass Index, and Body Image in Patients With Schizophrenia.

Science.gov (United States)

Oh, EunJung; Song, EunJu; Shin, JungEun

2017-12-01

The purposes of this study were to identify correlations between body mass index, body image, and self-esteem in patients with schizophrenia and to analyse the specific factors affecting self-esteem. This study had a descriptive design, utilising a cross-sectional survey. Participants were patients with schizophrenia who were admitted to a mental health facility in South Korea. A total of 180 questionnaires were distributed, and an appropriate total sample size of 167 valid questionnaires was analysed. Self-esteem was significantly correlated with body image, the subscale of appearance orientation, and body areas satisfaction. However, body mass index exhibited no significant correlation with any variable. The variables found to have a significant explanatory power of 21.4% were appearance orientation and body areas satisfaction. The explanatory power of all factors was 33.6%. The self-esteem of patients with schizophrenia was influenced by body mass index and body image. The positive symptoms of schizophrenia can be controlled by medication, whereas negative symptoms can be improved through education and nursing care with medication. Thus, psychiatric nurses should develop education and care programs that contribute to the positive body image and self-esteem of patients with schizophrenia. Copyright © 2017 Elsevier Inc. All rights reserved.

A spatial-spectral approach for deriving high signal quality eigenvectors for remote sensing image transformations

DEFF Research Database (Denmark)

Rogge, Derek; Bachmann, Martin; Rivard, Benoit

2014-01-01

Spectral decorrelation (transformations) methods have long been used in remote sensing. Transformation of the image data onto eigenvectors that comprise physically meaningful spectral properties (signal) can be used to reduce the dimensionality of hyperspectral images as the number of spectrally...... distinct signal sources composing a given hyperspectral scene is generally much less than the number of spectral bands. Determining eigenvectors dominated by signal variance as opposed to noise is a difficult task. Problems also arise in using these transformations on large images, multiple flight...... and spectral subsampling to the data, which is accomplished by deriving a limited set of eigenvectors for spatially contiguous subsets. These subset eigenvectors are compiled together to form a new noise reduced data set, which is subsequently used to derive a set of global orthogonal eigenvectors. Data from...

Evaluation of noni (Morinda citrifolia volatile profile by dynamic headspace and gas chromatography-mass spectrometry Avaliação do perfil de voláteis em noni (Morinda citrifolia por headspace dinâmico e cromatografia gasosa-espectrometria de massas

Directory of Open Access Journals (Sweden)

Adriana Sousa

2010-09-01

Full Text Available Noni is a fruit that has interested the scientific community due to its medicinal and functional activities. Different products that contain noni are already in the market, but their consumption could be impaired by their distinctive unpleasant aroma and flavor. The aim of this work was to evaluate the noni pulp volatile profile by dynamic headspace and gas chromatography-mass spectrometry. Thirty seven volatile compounds were detected, mainly alcohols (63.3%, esters (26.9%, cetones (7.4%, and acids (1.2%.O noni é um fruto que tem interessado à comunidade científica por sua atividade funcional e medicinal. Já se encontram no mercado diferentes produtos que contêm noni em sua composição, mas seu consumo tem sido prejudicado por seu aroma e sabor desagradáveis. O objetivo deste trabalho foi o de avaliar o perfil de voláteis da polpa de noni pela técnica de headspace dinâmico e cromatografia gasosa-espectrometria de massas. Foram detectados 37 compostos voláteis, sendo os principais: alcoóis (63,3%, ésteres (26,9%, cetonas (7,4% e ácidos (1,2%.

Open Computer Forensic Architecture a Way to Process Terabytes of Forensic Disk Images

Science.gov (United States)

Vermaas, Oscar; Simons, Joep; Meijer, Rob

This chapter describes the Open Computer Forensics Architecture (OCFA), an automated system that dissects complex file types, extracts metadata from files and ultimately creates indexes on forensic images of seized computers. It consists of a set of collaborating processes, called modules. Each module is specialized in processing a certain file type. When it receives a so called 'evidence', the information that has been extracted so far about the file together with the actual data, it either adds new information about the file or uses the file to derive a new 'evidence'. All evidence, original and derived, is sent to a router after being processed by a particular module. The router decides which module should process the evidence next, based upon the metadata associated with the evidence. Thus the OCFA system can recursively process images until from every compound file the embedded files, if any, are extracted, all information that the system can derive, has been derived and all extracted text is indexed. Compound files include, but are not limited to, archive- and zip-files, disk images, text documents of various formats and, for example, mailboxes. The output of an OCFA run is a repository full of derived files, a database containing all extracted information about the files and an index which can be used when searching. This is presented in a web interface. Moreover, processed data is easily fed to third party software for further analysis or to be used in data mining or text mining-tools. The main advantages of the OCFA system are Scalability, it is able to process large amounts of data.

Performance evaluation of inpatient service in Beijing: a horizontal comparison with risk adjustment based on Diagnosis Related Groups.

Science.gov (United States)

Jian, Weiyan; Huang, Yinmin; Hu, Mu; Zhang, Xiumei

2009-04-30

The medical performance evaluation, which provides a basis for rational decision-making, is an important part of medical service research. Current progress with health services reform in China is far from satisfactory, without sufficient regulation. To achieve better progress, an effective tool for evaluating medical performance needs to be established. In view of this, this study attempted to develop such a tool appropriate for the Chinese context. Data was collected from the front pages of medical records (FPMR) of all large general public hospitals (21 hospitals) in the third and fourth quarter of 2007. Locally developed Diagnosis Related Groups (DRGs) were introduced as a tool for risk adjustment and performance evaluation indicators were established: Charge Efficiency Index (CEI), Time Efficiency Index (TEI) and inpatient mortality of low-risk group cases (IMLRG), to reflect respectively work efficiency and medical service quality. Using these indicators, the inpatient services' performance was horizontally compared among hospitals. Case-mix Index (CMI) was used to adjust efficiency indices and then produce adjusted CEI (aCEI) and adjusted TEI (aTEI). Poisson distribution analysis was used to test the statistical significance of the IMLRG differences between different hospitals. Using the aCEI, aTEI and IMLRG scores for the 21 hospitals, Hospital A and C had relatively good overall performance because their medical charges were lower, LOS shorter and IMLRG smaller. The performance of Hospital P and Q was the worst due to their relatively high charge level, long LOS and high IMLRG. Various performance problems also existed in the other hospitals. It is possible to develop an accurate and easy to run performance evaluation system using Case-Mix as the tool for risk adjustment, choosing indicators close to consumers and managers, and utilizing routine report forms as the basic information source. To keep such a system running effectively, it is necessary to

Spectral detector CT-derived virtual non-contrast images: comparison of attenuation values with unenhanced CT.

Science.gov (United States)

Ananthakrishnan, Lakshmi; Rajiah, Prabhakar; Ahn, Richard; Rassouli, Negin; Xi, Yin; Soesbe, Todd C; Lewis, Matthew A; Lenkinski, Robert E; Leyendecker, John R; Abbara, Suhny

2017-03-01

To assess virtual non-contrast (VNC) images obtained on a detection-based spectral detector CT scanner and determine how attenuation on VNC images derived from various phases of enhanced CT compare to those obtained from true unenhanced images. In this HIPAA compliant, IRB approved prospective multi-institutional study, 46 patients underwent pre- and post-contrast imaging on a prototype dual-layer spectral detector CT between October 2013 and November 2015, yielding 84 unenhanced and VNC pairs (25 arterial, 39 portal venous/nephrographic, 20 urographic). Mean attenuation was measured by one of three readers in the liver, spleen, kidneys, psoas muscle, abdominal aorta, and subcutaneous fat. Equivalence testing was used to determine if the mean difference between unenhanced and VNC attenuation was less than 5, 10, or 15 HU. VNC image quality was assessed on a 5 point scale. Mean difference between unenhanced and VNC attenuation was VNC attenuation were equivalent in all tissues except fat using a threshold of VNC overestimated the HU relative to unenhanced images. VNC image quality was rated as excellent or good in 84% of arterial phase and 85% of nephrographic phase cases, but only 40% of urographic phase. VNC images derived from novel dual layer spectral detector CT demonstrate attenuation values similar to unenhanced images in all tissues evaluated except for subcutaneous fat. Further study is needed to determine if attenuation thresholds currently used clinically for common pathology should be adjusted, particularly for lesions containing fat.

Comparing the Dry Season In-Situ Leaf Area Index (LAI Derived from High-Resolution RapidEye Imagery with MODIS LAI in a Namibian Savanna

Directory of Open Access Journals (Sweden)

Manuel J. Mayr

2015-04-01

Full Text Available The Leaf Area Index (LAI is one of the most frequently applied measures to characterize vegetation and its dynamics and functions with remote sensing. Satellite missions, such as NASA’s Moderate Resolution Imaging Spectroradiometer (MODIS operationally produce global datasets of LAI. Due to their role as an input to large-scale modeling activities, evaluation and verification of such datasets are of high importance. In this context, savannas appear to be underrepresented with regards to their heterogeneous appearance (e.g., tree/grass-ratio, seasonality. Here, we aim to examine the LAI in a heterogeneous savanna ecosystem located in Namibia’s Owamboland during the dry season. Ground measurements of LAI are used to derive a high-resolution LAI model with RapidEye satellite data. This model is related to the corresponding MODIS LAI/FPAR (Fraction of Absorbed Photosynthetically Active Radiation scene (MOD15A2 in order to evaluate its performance at the intended annual minimum during the dry season. Based on a field survey we first assessed vegetation patterns from species composition and elevation for 109 sites. Secondly, we measured in situ LAI to quantitatively estimate the available vegetation (mean = 0.28. Green LAI samples were then empirically modeled (LAImodel with high resolution RapidEye imagery derived Difference Vegetation Index (DVI using a linear regression (R2 = 0.71. As indicated by several measures of model performance, the comparison with MOD15A2 revealed moderate consistency mostly due to overestimation by the aggregated LAImodel. Model constraints aside, this study may point to important issues for MOD15A2 in savannas concerning the underlying MODIS Land Cover product (MCD12Q1 and a potential adjustment by means of the MODIS Burned Area product (MCD45A1.

Derivation of the scan time requirement for maintaining a consistent PET image quality

International Nuclear Information System (INIS)

Kim, Jin Su; Lee, Jae Sung; Kim, Seok-Ki

2015-01-01

Objectives: the image quality of PET for larger patients is relatively poor, even though the injection dose is optimized considering the NECR characteristics of the PET scanner. This poor image quality is due to the lower level of maximum NECR that can be achieved in these large patients. The aim of this study was to optimize the PET scan time to obtain a consistent PET image quality regardless of the body size, based on the relationship between the patient specific NECR (pNECR) and body weight. Methods: eighty patients (M/F=53/27, body weight: 059 ± 1 kg) underwent whole-body FDG PET scans using a Philips GEMINI GS PET/CT scanner after an injection of 0.14 mCi/kg FDG. The relationship between the scatter fraction (SF) and body weight was determined by repeated Monte Carlo simulations using a NEMA scatter phantom, the size of which varied according to the relationship between the abdominal circumference and body weight. Using this information, the pNECR was calculated from the prompt and delayed PET sinograms to obtain the prediction equation of NECR vs. body weight. The time scaling factor (F TS ) for the scan duration was finally derived to make PET images with equivalent SNR levels. Results: the SF and NECR had the following nonlinear relationships with the body weight: SF=0.15 ⋅ body weight 0.3 and NECR = 421.36 (body weight) −0.84 . The equation derived for F TS was 0.01⋅ body weight + 0.2, which means that, for example, a 120-kg person should be scanned 1.8 times longer than a 70 kg person, or the scan time for a 40-kg person can be reduced by 30%. Conclusion: the equation of the relative time demand derived in this study will be useful for maintaining consistent PET image quality in clinics

Indexation of cardiac output to biometric parameters in critically ill patients: A systematic analysis of a transpulmonary thermodilution-derived database.

Science.gov (United States)

Saugel, Bernd; Mair, Sebastian; Götz, Simon Q; Tschirdewahn, Julia; Frank, Johanna; Höllthaler, Josef; Schmid, Roland M; Huber, Wolfgang

2015-10-01

Cardiac output (CO) (liters per minute) is usually normalized (ie, indexed) to the patient's body surface area (BSA) resulting in the hemodynamic variable cardiac index (CI) (liters per minute per square meter). We aimed (1) to evaluate the impact of different body weight-based CO indexations on the resulting CI values and (2) to identify biometric parameters independently associated with CO in critically ill patients. The study is an analysis of a database containing transpulmonary thermodilution-derived hemodynamic variables of 234 medical intensive care unit patients. Cardiac index indexed to actual BSA was statistically significantly lower compared with CI indexed to predicted BSA in the totality of patients and in the subgroups of patients with body mass index greater than or equal to 25 kg/m(2) but less than 30 kg/m(2) and body mass index greater than or equal to 30 kg/m(2) (with a statistically significant difference in the proportion of low and high CI measurements). Multivariate analysis of the first CO measurement of each patient demonstrated that CO was independently associated with age (P biometric factors independently associated with CO. Age was identified as the most important factor with each year of age decreasing CO by 66 mL/min (95% confidence interval, 47-86 mL/min). The indexation of CO to BSA is highly dependent on the body weight estimation formula used to calculate BSA. Cardiac output is independently associated with the biometric factors age, height, and BWact. These factors might be considered for indexation of CO. Copyright © 2015 Elsevier Inc. All rights reserved.

A Miniaturized Antenna with Negative Index Metamaterial Based on Modified SRR and CLS Unit Cell for UWB Microwave Imaging Applications

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Md. Moinul Islam

2015-01-01

Full Text Available A miniaturized antenna employing a negative index metamaterial with modified split-ring resonator (SRR and capacitance-loaded strip (CLS unit cells is presented for Ultra wideband (UWB microwave imaging applications. Four left-handed (LH metamaterial (MTM unit cells are located along one axis of the antenna as the radiating element. Each left-handed metamaterial unit cell combines a modified split-ring resonator (SRR with a capacitance-loaded strip (CLS to obtain a design architecture that simultaneously exhibits both negative permittivity and negative permeability, which ensures a stable negative refractive index to improve the antenna performance for microwave imaging. The antenna structure, with dimension of 16 × 21 × 1.6 mm3, is printed on a low dielectric FR4 material with a slotted ground plane and a microstrip feed. The measured reflection coefficient demonstrates that this antenna attains 114.5% bandwidth covering the frequency band of 3.4–12.5 GHz for a voltage standing wave ratio of less than 2 with a maximum gain of 5.16 dBi at 10.15 GHz. There is a stable harmony between the simulated and measured results that indicate improved nearly omni-directional radiation characteristics within the operational frequency band. The stable surface current distribution, negative refractive index characteristic, considerable gain and radiation properties make this proposed negative index metamaterial antenna optimal for UWB microwave imaging applications.

Alkyl-fluorinated thymidine derivatives for imaging cell proliferation

International Nuclear Information System (INIS)

Toyohara, Jun; Hayashi, Akio; Gogami, Akie; Hamada, Masahiro; Hamashima, Yoshio; Katoh, Takahiro; Node, Manabu; Fujibayashi, Yasuhisa

2006-01-01

Derivatives of 2'-deoxyuridine that contain fluoroalkyl groups at the C5 position and derivatives of thymidine that contain fluoroalkyl groups at the N3 position were synthesized and examined in three in vitro assays designed to evaluate their potential as radiopharmaceuticals for imaging cellular proliferation. Three of the former nucleosides and five of the latter were synthesized. The three assays were as follows: (a) phosphoryl transfer assay, which showed that all three of the former nucleosides and four of the latter ones were phosphorylated by recombinant human thymidine kinase 1 (TK1) and that N 3 -(2-fluoroethyl)-thymidine (NFT202) was the most potent substrate of the eight nucleosides studied; (b) transport assay, which indicated that all eight nucleosides had good affinity for an 6-[(4-nitrobenzyl)thio]-9-β-D-ribofuranosylpurine-sensitive mouse erythrocyte nucleoside transporter, with inhibition constants in the range of 0.02-0.55 mM; and (c) degradation assay, which showed that all but one of the former nucleosides and none of the latter were degraded by recombinant Escherichia coli thymidine phosphorylase (an enzyme that catalyzes the glycosidic bond of thymidine and 2'-deoxyuridine derivatives). From these in vitro screening assays, we selected NFT202 as a candidate for subsequent in vivo evaluation because this compound met the three minimum requirements of the in vitro screening assays and had the most potent phosphorylation activity as a substrate for recombinant human TK1

The Psychometric Assessment of Children with Learning Disabilities: An Index Derived from a Principal Components Analysis of the WISC-R.

Science.gov (United States)

Lawson, J. S.; Inglis, James

1984-01-01

A learning disability index (LDI) for the assessment of intellectual deficits on the Wechsler Intelligence Scale for Children-Revised (WISC-R) is described. The Factor II score coefficients derived from an unrotated principal components analysis of the WISC-R normative data, in combination with the individual's scaled scores, are used for this…

Integration of biological responses from a suite of bioassays for the Venice Lagoon (Italy) through sediment toxicity index - part A: development and comparison of two methodological approaches.

Science.gov (United States)

Losso, Chiara; Novelli, Alessandra Arizzi; De Salvador, Davide; Ghetti, Pier Francesco; Ghirardini, Annamaria Volpi

2010-12-01

Marine and coastal quality assessment, based on test batteries involving a wide array of endpoints, organisms and test matrices, needs for setting up toxicity indices that integrate multiple toxicological measures for decision-making processes and that classify the continuous toxicity response into discrete categories according to the European Water Framework Directive. Two toxicity indices were developed for the lagoon environment such as the Venice Lagoon. Stepwise procedure included: the construction of a database that identified test-matrix pairs (indicators); the selection of a minimum number of ecotoxicological indicators, called toxicological core metrics (CMs-tox) on the basis of specific criteria; the development of toxicity scores for each CM-tox; the integration of the CMs-tox into two indices, the Toxicity Effect Index (TEI), based on the transformation of Toxic Unit (TU) data that were integrated as logarithmic sum, and the Weighted Average Toxicity Index (WATI), starting from toxicity classes integrated as weighted mean. Results from the indices are compared; advantages and drawbacks of both approaches are discussed. Copyright © 2010. Published by Elsevier Ltd.

Gradient-Index Optics

Science.gov (United States)

2010-03-31

nonimaging design capabilities to incorporate 1. REPORT DATE (DD-MM-YYYY) 4. TITLE AND SUBTITLE 12-04-2011 13. SUPPLEMENTARY NOTES The views, opinions...Box 12211 Research Triangle Park, NC 27709-2211 15. SUBJECT TERMS Imaging Optics, Nonimaging Optics, Gradient Index Optics, Camera, Concentrator...imaging and nonimaging design capabilities to incorporate manufacturable GRIN lenses can provide imaging lens systems that are compact and

CT urography in the urinary bladder: To compare excretory phase images using a low noise index and a high noise index with adaptive noise reduction filter

International Nuclear Information System (INIS)

Takeyama, Nobuyuki; Hayashi, Takaki; Ohgiya, Yoshimitsu

2011-01-01

Background: Although CT urography (CTU) is widely used for the evaluation of the entire urinary tract, the most important drawback is the radiation exposure. Purpose: To evaluate the effect of a noise reduction filter (NRF) using a phantom and to quantitatively and qualitatively compare excretory phase (EP) images using a low noise index (NI) with those using a high NI and postprocessing NRF (pNRF). Material and Methods: Each NI value was defined for a slice thickness of 5 mm, and reconstructed images with a slice thickness of 1.25 mm were assessed. Sixty patients who were at high risk of developing bladder tumors (BT) were divided into two groups according to whether their EP images were obtained using an NI of 9.88 (29 patients; group A) or an NI of 20 and pNRF (31 patients; group B). The CT dose index volume (CTDI vol ) and the contrast-to-noise ratio (CNR) of the bladder with respect to the anterior pelvic fat were compared in both groups. Qualitative assessment of the urinary bladder for image noise, sharpness, streak artifacts, homogeneity, and the conspicuity of polypoid or sessile-shaped BTs with a short-axis diameter greater than 10 mm was performed using a 3-point scale. Results: The phantom study showed noise reduction of approximately 40% and 76% dose reduction between group A and group B. CTDI vol demonstrated a 73% reduction in group B (4.6 ± 1.1 mGy) compared with group A (16.9 ± 3.4 mGy). The CNR value was not significantly different (P = 0.60) between group A (16.1 ± 5.1) and group B (16.6 ± 7.6). Although group A was superior (P < 0.01) to group B with regard to image noise, other qualitative analyses did not show significant differences. Conclusion: EP images using a high NI and pNRF were quantitatively and qualitatively comparable to those using a low NI, except with regard to image noise

On the refractive index of sodium iodide solutions for index matching in PIV

Science.gov (United States)

Bai, Kunlun; Katz, Joseph

2014-04-01

Refractive index matching has become a popular technique for facilitating applications of modern optical diagnostic techniques, such as particle image velocimetry, in complex systems. By matching the refractive index of solid boundaries with that of the liquid, unobstructed optical paths can be achieved for illumination and image acquisition. In this research note, we extend previously provided data for the refractive index of aqueous solutions of sodium iodide (NaI) for concentrations reaching the temperature-dependent solubility limit. Results are fitted onto a quadratic empirical expression relating the concentration to the refractive index. Temperature effects are also measured. The present range of indices, 1.333-1.51, covers that of typical transparent solids, from silicone elastomers to several recently introduced materials that could be manufactured using rapid prototyping. We also review briefly previous measurements of the refractive index, viscosity, and density of NaI solutions, as well as prior research that has utilized this fluid.

Eyewear-style three-dimensional endoscope derived from microstructured polymer fiber with the function of image transmission

International Nuclear Information System (INIS)

Kong De-Peng; Wang Li-Li; He Zheng-Quan; Ma Tian; Chu Jiu-Rong

2013-01-01

A method of fabricating multi-core polymer image fiber is proposed. Image fiber preform is fabricated by stacking thousands of polymer fibers each with a 0.25-mm diameter orderly in a die by only one step. The preform is heated and stretched into image fiber with an outer diameter of 2 mm. Then a portable eyewear-style three-dimensional (3D) endoscope system is designed, fabricated, and characterized. This endoscopic system is composed of two graded index lenses, two pieces of 0.35-m length image guide fibers, and a pair of oculars. It shows good flexibility and portability, and can provide the depth information accordingly. (general)

An index with improved diagnostic accuracy for the diagnosis of Crohn's disease derived from the Lennard-Jones criteria.

Science.gov (United States)

Reinisch, S; Schweiger, K; Pablik, E; Collet-Fenetrier, B; Peyrin-Biroulet, L; Alfaro, I; Panés, J; Moayyedi, P; Reinisch, W

2016-09-01

The Lennard-Jones criteria are considered the gold standard for diagnosing Crohn's disease (CD) and include the items granuloma, macroscopic discontinuity, transmural inflammation, fibrosis, lymphoid aggregates and discontinuous inflammation on histology. The criteria have never been subjected to a formal validation process. To develop a validated and improved diagnostic index based on the items of Lennard-Jones criteria. Included were 328 adult patients with long-standing CD (median disease duration 10 years) from three centres and classified as 'established', 'probable' or 'non-CD' by Lennard-Jones criteria at time of diagnosis. Controls were patients with ulcerative colitis (n = 170). The performance of each of the six diagnostic items of Lennard-Jones criteria was modelled by logistic regression and a new index based on stepwise backward selection and cut-offs was developed. The diagnostic value of the new index was analysed by comparing sensitivity, specificity and accuracy vs. Lennard-Jones criteria. By Lennard-Jones criteria 49% (n = 162) of CD patients would have been diagnosed as 'non-CD' at time of diagnosis (sensitivity/specificity/accuracy, 'established' CD: 0.34/0.99/0.67; 'probable' CD: 0.51/0.95/0.73). A new index was derived from granuloma, fibrosis, transmural inflammation and macroscopic discontinuity, but excluded lymphoid aggregates and discontinuous inflammation on histology. Our index provided improved diagnostic accuracy for 'established' and 'probable' CD (sensitivity/specificity/accuracy, 'established' CD: 0.45/1/0.72; 'probable' CD: 0.8/0.85/0.82), including the subgroup isolated colonic CD ('probable' CD, new index: 0.73/0.85/0.79; Lennard-Jones criteria: 0.43/0.95/0.69). We developed an index based on items of Lennard-Jones criteria providing improved diagnostic accuracy for the differential diagnosis between CD and UC. © 2016 John Wiley & Sons Ltd.

An Amateur's Guide to Observing and Imaging the Heavens

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Morison, Ian

2014-06-01

Foreword; Acknowledgments; Prologue: a tale of two scopes; 1. Telescope and observing fundamentals; 2. Refractors; 3. Binoculars and spotting scopes; 4. The Newtonian telescope and its derivatives; 5. The Cassegrain telescope and its derivatives - Schmidt-Cassegrains and Maksutovs; 6. Telescope maintenance, collimation and star testing; 7. Telescope accessories: finders, eyepieces and bino-viewers; 8. Telescope mounts: alt/az and equatorial with their computerised variants; 9. The art of visual observing; 10. Visual observations of the Moon and planets; 11. Imaging the Moon and planets with DSLRs and web-cams; 12. Observing and imaging the Sun in white light and H-alpha; 13. Observing with an astro-video camera to 'see' faint objects; 14. Deep sky imaging with standard and H-alpha modified DSLR cameras; 15. Deep sky imaging with cooled CCD cameras; 16. Auto-guiding techniques and equipment; 17. Spectral studies of the Sun, stars and galaxies; 18. Improving and enhancing images in Photoshop; Index.

Optimized Data Indexing Algorithms for OLAP Systems

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Lucian BORNAZ

2010-12-01

Full Text Available The need to process and analyze large data volumes, as well as to convey the information contained therein to decision makers naturally led to the development of OLAP systems. Similarly to SGBDs, OLAP systems must ensure optimum access to the storage environment. Although there are several ways to optimize database systems, implementing a correct data indexing solution is the most effective and less costly. Thus, OLAP uses indexing algorithms for relational data and n-dimensional summarized data stored in cubes. Today database systems implement derived indexing algorithms based on well-known Tree, Bitmap and Hash indexing algorithms. This is because no indexing algorithm provides the best performance for any particular situation (type, structure, data volume, application. This paper presents a new n-dimensional cube indexing algorithm, derived from the well known B-Tree index, which indexes data stored in data warehouses taking in consideration their multi-dimensional nature and provides better performance in comparison to the already implemented Tree-like index types.

A new method of derived equatorial plasma bubbles motion by tracing OI 630 nm emission all-sky images

Science.gov (United States)

Li, M.; Yu, T.; Chunliang, X.; Zuo, X.; Liu, Z.

2017-12-01

A new method for estimating the equatorial plasma bubbles (EPBs) motions from airglow emission all-sky images is presented in this paper. This method, which is called 'cloud-derived wind technology' and widely used in satellite observation of wind, could reasonable derive zonal and meridional velocity vectors of EPBs drifts by tracking a series of successive airglow 630.0 nm emission images. Airglow emission images data are available from an all sky airglow camera in Hainan Fuke (19.5°N, 109.2°E) supported by China Meridional Project, which can receive the 630.0nm emission from the ionosphere F region at low-latitudes to observe plasma bubbles. A series of pretreatment technology, e.g. image enhancement, orientation correction, image projection are utilized to preprocess the raw observation. Then the regions of plasma bubble extracted from the images are divided into several small tracing windows and each tracing window can find a target window in the searching area in following image, which is considered as the position tracing window moved to. According to this, velocities in each window are calculated by using the technology of cloud-derived wind. When applying the cloud-derived wind technology, the maximum correlation coefficient (MCC) and the histogram of gradient (HOG) methods to find the target window, which mean to find the maximum correlation and the minimum euclidean distance between two gradient histograms in respectively, are investigated and compared in detail. The maximum correlation method is fianlly adopted in this study to analyze the velocity of plasma bubbles because of its better performance than HOG. All-sky images from Hainan Fuke, between August 2014 and October 2014, are analyzed to investigate the plasma bubble drift velocities using MCC method. The data at different local time at 9 nights are studied and find that zonal drift velocity in different latitude at different local time ranges from 50 m/s to 180 m/s and there is a peak value at

Biofiltração de compostos orgânicos voláteis e gás sulfídrico em estações de despejos industriais de processamento de hidrocarbonetos.

OpenAIRE

Beatrix Nery Villa Martignoni

2007-01-01

Neste trabalho foi estudado o tratamento simultâneo por biofiltração de emissões de compostos orgânicos voláteis, COV e gás sulfídrico, H2S, em estações de tratamento de despejos industriais, de refinaria de petróleo, ETDI. A biofiltração dos gases emanados da EDTI mostrou ser uma técnica de alta eficiência, atingindo valores de 95 a 99 % para tratamento simultâneo de COV e H2S em concentrações de 1000 e 100 ppmv, respectivamente. Foram realizados testes em 95 dias consecutivos...

Low dose reconstruction algorithm for differential phase contrast imaging.

Science.gov (United States)

Wang, Zhentian; Huang, Zhifeng; Zhang, Li; Chen, Zhiqiang; Kang, Kejun; Yin, Hongxia; Wang, Zhenchang; Marco, Stampanoni

2011-01-01

Differential phase contrast imaging computed tomography (DPCI-CT) is a novel x-ray inspection method to reconstruct the distribution of refraction index rather than the attenuation coefficient in weakly absorbing samples. In this paper, we propose an iterative reconstruction algorithm for DPCI-CT which benefits from the new compressed sensing theory. We first realize a differential algebraic reconstruction technique (DART) by discretizing the projection process of the differential phase contrast imaging into a linear partial derivative matrix. In this way the compressed sensing reconstruction problem of DPCI reconstruction can be transformed to a resolved problem in the transmission imaging CT. Our algorithm has the potential to reconstruct the refraction index distribution of the sample from highly undersampled projection data. Thus it can significantly reduce the dose and inspection time. The proposed algorithm has been validated by numerical simulations and actual experiments.

Application of a Simplified Method for Estimating Perfusion Derived from Diffusion-Weighted MR Imaging in Glioma Grading.

Science.gov (United States)

Cao, Mengqiu; Suo, Shiteng; Han, Xu; Jin, Ke; Sun, Yawen; Wang, Yao; Ding, Weina; Qu, Jianxun; Zhang, Xiaohua; Zhou, Yan

2017-01-01

Purpose : To evaluate the feasibility of a simplified method based on diffusion-weighted imaging (DWI) acquired with three b -values to measure tissue perfusion linked to microcirculation, to validate it against from perfusion-related parameters derived from intravoxel incoherent motion (IVIM) and dynamic contrast-enhanced (DCE) magnetic resonance (MR) imaging, and to investigate its utility to differentiate low- from high-grade gliomas. Materials and Methods : The prospective study was approved by the local institutional review board and written informed consent was obtained from all patients. From May 2016 and May 2017, 50 patients confirmed with glioma were assessed with multi- b -value DWI and DCE MR imaging at 3.0 T. Besides conventional apparent diffusion coefficient (ADC 0,1000 ) map, perfusion-related parametric maps for IVIM-derived perfusion fraction ( f ) and pseudodiffusion coefficient (D*), DCE MR imaging-derived pharmacokinetic metrics, including K trans , v e and v p , as well as a metric named simplified perfusion fraction (SPF), were generated. Correlation between perfusion-related parameters was analyzed by using the Spearman rank correlation. All imaging parameters were compared between the low-grade ( n = 19) and high-grade ( n = 31) groups by using the Mann-Whitney U test. The diagnostic performance for tumor grading was evaluated with receiver operating characteristic (ROC) analysis. Results : SPF showed strong correlation with IVIM-derived f and D* ( ρ = 0.732 and 0.716, respectively; both P simplified method to measure tissue perfusion based on DWI by using three b -values may be helpful to differentiate low- from high-grade gliomas. SPF may serve as a valuable alternative to measure tumor perfusion in gliomas in a noninvasive, convenient and efficient way.

The relationship between image quality and CT dose index of multi-slice low-dose chest CT

International Nuclear Information System (INIS)

Zhu Xiaohua; Shao Jiang; Shi Jingyun; You Zhengqian; Li Shijun; Xue Yongming

2003-01-01

Objective: To explore the rationality and possibility of multi-slice low-dose CT scan in the examination of the chest. Methods: (1) X-ray dose index measurement: 120 kV tube voltage, 0.75 s rotation, 8 mm and 3 mm slice thickness, and the tube current setting of 115.0, 40.0, 25.0, and 7.5 mAs were employed in every section. The X-ray radiation dose was measured and compared statistically. (2) phantom measurement of homogeneity and noise: The technical parameters were 120 kV, 0.75 s, 8 mm and 3 mm sections, and every slice was scanned using tube current of 115.0, 40.0, 25.0, and 7.5 mAs. Five same regions of interest were measured on every image. The homogeneity and noise level of CT were appraised. (3) The multi-slice low-dose CT in patients: 30 patients with mass and 30 with patch shadow in the lung were selected randomly. The technical parameters were 120 kV, 0.75 s, 8 mm and 3 mm slice thickness. 115.0, 40.0, 25.0, 15.0, and 7.5 mAs tube current were employed in each same slice. Otherwise, 15 cases with helical scan were examined using 190, 150, 40, 25, and 15 mAs tube current. The reconstruction images of MIP, MPR, CVR, HRCT, 3D, CT virtual endoscopy, and variety of interval reconstruction were compared. (4) Evaluation of image quality: CT images were evaluated by four doctors using single-blind method, and 3 degrees including normal image, image with few artifact, and image with excessive artifact, were employed and analyzed statistically. Results: (1) The CT dose index with 115.0 mAs tube current exceeded those of 40.0, 25.0, and 7.5 mAs by about 60%, 70%, and 85%, respectively. (2) The phantom measurement showed that the lower of CT dose the lower of homogeneity, the lower of CT dose the higher of noise level. (3) Result of image quality evaluation: The percentage of the normal image had no significant difference between 8 and 3 mm in 115, 40, and 25 mAs (P>0.05). Conclusion: Multi-slice low-dose chest CT technology may protect the patients and guarantee the

Comparison of Body Image and its Relationship with Body Mass Index (BMI in High School Students of Ahvaz, Iran

Directory of Open Access Journals (Sweden)

Mahsa Behdarvandi

2017-02-01

Full Text Available BackgroundIt is not clearly specified that which of the components of body mass index (BMI affect body image and which of them do not. Given that having information in this regard is of special importance as a basis for future planning for adolescents, the present research aimed to compare body image in female and male adolescents and study its relationship with body mass index in high school students of Ahwaz, Khuzestan Province in the academic year 2015-2016.Materials and MethodsIn this descriptive-analytic study, 200 high school students were selected as the sample using the random cluster sampling method. The required data were collected using demographic questionnaire, anthropometric data checklist (height and weight, and the Multidimensional Body-Self Relations Questionnaire (MBSRQ. All descriptive and inferential statistics tests were performed using SPSS-17 at a confidence level of 95%.Results: The students ranged from 15 to 18 years old. Equal distribution was employed among all four grades of high school. Body mass index (BMI in male students showed a significant inverse relationship only with appearance orientation (P

DNA index determination with Automated Cellular Imaging System (ACIS in Barrett's esophagus: Comparison with CAS 200

Directory of Open Access Journals (Sweden)

Klein Michael

2005-08-01

Full Text Available Abstract Background For solid tumors, image cytometry has been shown to be more sensitive for diagnosing DNA content abnormalities (aneuploidy than flow cytometry. Image cytometry has often been performed using the semi-automated CAS 200 system. Recently, an Automated Cellular Imaging System (ACIS was introduced to determine DNA content (DNA index, but it has not been validated. Methods Using the CAS 200 system and ACIS, we compared the DNA index (DI obtained from the same archived formalin-fixed and paraffin embedded tissue samples from Barrett's esophagus related lesions, including samples with specialized intestinal metaplasia without dysplasia, low-grade dysplasia, high-grade dysplasia and adenocarcinoma. Results Although there was a very good correlation between the DI values determined by ACIS and CAS 200, the former was 25% more sensitive in detecting aneuploidy. ACIS yielded a mean DI value 18% higher than that obtained by CAS 200 (p t test. In addition, the average time required to perform a DNA ploidy analysis was shorter with the ACIS (30–40 min than with the CAS 200 (40–70 min. Results obtained by ACIS gave excellent inter-and intra-observer variability (coefficient of correlation >0.9 for both, p Conclusion Compared with the CAS 200, the ACIS is a more sensitive and less time consuming technique for determining DNA ploidy. Results obtained by ACIS are also highly reproducible.

Phenotype analysis of early risk factors from electronic medical records improves image-derived diagnostic classifiers for optic nerve pathology

Science.gov (United States)

Chaganti, Shikha; Nabar, Kunal P.; Nelson, Katrina M.; Mawn, Louise A.; Landman, Bennett A.

2017-03-01

We examine imaging and electronic medical records (EMR) of 588 subjects over five major disease groups that affect optic nerve function. An objective evaluation of the role of imaging and EMR data in diagnosis of these conditions would improve understanding of these diseases and help in early intervention. We developed an automated image processing pipeline that identifies the orbital structures within the human eyes from computed tomography (CT) scans, calculates structural size, and performs volume measurements. We customized the EMR-based phenome-wide association study (PheWAS) to derive diagnostic EMR phenotypes that occur at least two years prior to the onset of the conditions of interest from a separate cohort of 28,411 ophthalmology patients. We used random forest classifiers to evaluate the predictive power of image-derived markers, EMR phenotypes, and clinical visual assessments in identifying disease cohorts from a control group of 763 patients without optic nerve disease. Image-derived markers showed more predictive power than clinical visual assessments or EMR phenotypes. However, the addition of EMR phenotypes to the imaging markers improves the classification accuracy against controls: the AUC improved from 0.67 to 0.88 for glaucoma, 0.73 to 0.78 for intrinsic optic nerve disease, 0.72 to 0.76 for optic nerve edema, 0.72 to 0.77 for orbital inflammation, and 0.81 to 0.85 for thyroid eye disease. This study illustrates the importance of diagnostic context for interpretation of image-derived markers and the proposed PheWAS technique provides a flexible approach for learning salient features of patient history and incorporating these data into traditional machine learning analyses.

Parameter-based estimation of CT dose index and image quality using an in-house android™-based software

International Nuclear Information System (INIS)

Mubarok, S; Lubis, L E; Pawiro, S A

2016-01-01

Compromise between radiation dose and image quality is essential in the use of CT imaging. CT dose index (CTDI) is currently the primary dosimetric formalisms in CT scan, while the low and high contrast resolutions are aspects indicating the image quality. This study was aimed to estimate CTDI vol and image quality measures through a range of exposure parameters variation. CTDI measurements were performed using PMMA (polymethyl methacrylate) phantom of 16 cm diameter, while the image quality test was conducted by using catphan ® 600. CTDI measurements were carried out according to IAEA TRS 457 protocol using axial scan mode, under varied parameters of tube voltage, collimation or slice thickness, and tube current. Image quality test was conducted accordingly under the same exposure parameters with CTDI measurements. An Android™ based software was also result of this study. The software was designed to estimate the value of CTDI vol with maximum difference compared to actual CTDI vol measurement of 8.97%. Image quality can also be estimated through CNR parameter with maximum difference to actual CNR measurement of 21.65%. (paper)

Analysis of photon-scanning tunneling microscope images of inhomogeneous samples: Determination of the local refractive index of channel waveguides

International Nuclear Information System (INIS)

Bourillot, E.; Fornel, F. de.; Goudonnet, J.P.

1995-01-01

Channel waveguides are imaged by a photon-scanning tunneling microscope (PSTM). The polarization of the light and its orientation with respect to the guide aids are shown to be very important parameters in the analysis of the images of such samples. We simulated image formation for the plane of incidence parallel to the axis of the guide. Our theoretical results are qualitatively in agreement with our measurements. These results show the ability of the PSTM to give information about the local refractive-index variations of a sample. 21 refs., 14 figs

Distinguishing plant population and variety with UAV-derived vegetation indices

Science.gov (United States)

Oakes, Joseph; Balota, Maria

2017-05-01

Variety selection and seeding rate are two important choice that a peanut grower must make. High yielding varieties can increase profit with no additional input costs, while seeding rate often determines input cost a grower will incur from seed costs. The overall purpose of this study was to examine the effect that seeding rate has on different peanut varieties. With the advent of new UAV technology, we now have the possibility to use indices collected with the UAV to measure emergence, seeding rate, growth rate, and perhaps make yield predictions. This information could enable growers to make management decisions early in the season based on low plant populations due to poor emergence, and could be a useful tool for growers to use to estimate plant population and growth rate in order to help achieve desired crop stands. Red-Green-Blue (RGB) and near-infrared (NIR) images were collected from a UAV platform starting two weeks after planting and continued weekly for the next six weeks. Ground NDVI was also collected each time aerial images were collected. Vegetation indices were derived from both the RGB and NIR images. Greener area (GGA- the proportion of green pixels with a hue angle from 80° to 120°) and a* (the average red/green color of the image) were derived from the RGB images while Normalized Differential Vegetative Index (NDVI) was derived from NIR images. Aerial indices were successful in distinguishing seeding rates and determining emergence during the first few weeks after planting, but not later in the season. Meanwhile, these aerial indices are not an adequate predictor of yield in peanut at this point.

2008 Natural Resource Management Index (NRMI)

Data.gov (United States)

National Aeronautics and Space Administration — The 2008 Natural Resources Management Index (NRMI) is a composite index for 226 countries derived from the average of four proximity-to-target scores from eco-region...

Ray transference of a system with radial gradi- ent index

Directory of Open Access Journals (Sweden)

W. F. Harris

2012-12-01

Full Text Available The ray transference is central to the understanding of the first-order optical character of an optical system including the visual optical system of the eye.  It can be calculated for dioptric and catadioptric systems from a knowledge of curvatures, tilts and spacing of surfaces in the system provided the material between successive surfaces has a uniform index of refraction.  However the index of the natural lens of the eye is not uniform but varies with position.  There is a need, therefore, for a method of calculating the transference of systems containing such gradient-index elements.  As a first step this paper shows that the transference of elements in which the index varies radially can be obtained directly from published formulae.  The transferences of radial-gradient systems are examined.  Expressions are derived for several properties including the power, the front- and back-surface powers and the locations of the cardinal points.  Equations are obtained for rays through such systems and for the locations of images of object points through them.  Numerical examples are presented in the appen-dix. (S Afr Optom 2012 71(2 57-63

Genotypic variation in transpiration efficiency due to differences in photosynthetic capacity among sugarcane-related clones.

Science.gov (United States)

Li, Chunjia; Jackson, Phillip; Lu, Xin; Xu, Chaohua; Cai, Qing; Basnayake, Jayapathi; Lakshmanan, Prakash; Ghannoum, Oula; Fan, Yuanhong

2017-04-01

Sugarcane, derived from the hybridization of Saccharum officinarum×Saccharum spontaneum, is a vegetative crop in which the final yield is highly driven by culm biomass production. Cane yield under irrigated or rain-fed conditions could be improved by developing genotypes with leaves that have high intrinsic transpiration efficiency, TEi (CO2 assimilation/stomatal conductance), provided this is not offset by negative impacts from reduced conductance and growth rates. This study was conducted to partition genotypic variation in TEi among a sample of diverse clones from the Chinese collection of sugarcane-related germplasm into that due to variation in stomatal conductance versus that due to variation in photosynthetic capacity. A secondary goal was to define protocols for optimized larger-scale screening of germplasm collections. Genotypic variation in TEi was attributed to significant variation in both stomatal and photosynthetic components. A number of genotypes were found to possess high TEi as a result of high photosynthetic capacity. This trait combination is expected to be of significant breeding value. It was determined that a small number of observations (16) is sufficient for efficiently screening TEi in larger populations of sugarcane genotypes The research methodology and results reported are encouraging in supporting a larger-scale screening and introgression of high transpiration efficiency in sugarcane breeding. However, further research is required to quantify narrow sense heritability as well as the leaf-to-field translational potential of genotypic variation in transpiration efficiency-related traits observed in this study. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Near infrared spatial frequency domain fluorescence imaging of tumor phantoms containing erythrocyte-derived optical nanoplatforms

Science.gov (United States)

Burns, Joshua M.; Schaefer, Elise; Anvari, Bahman

2018-02-01

Light-activated theranostic constructs provide a multi-functional platform for optical imaging and phototherapeutic applications. Our group has engineered nano-sized vesicles derived from erythrocytes that encapsulate the FDAapproved near infrared (NIR) absorber indocyanine green (ICG). We refer to these constructs as NIR erythrocytemimicking transducers (NETs). Once photo-excited by NIR light these constructs can transduce the photons energy to emit fluorescence, generate heat, or induce chemical reactions. In this study, we investigated fluorescence imaging of NETs embedded within tumor phantoms using spatial frequency domain imaging (SFDI). Using SFDI, we were able to fluorescently image simulated tumors doped with different concentration of NETs. These preliminary results suggest that NETs can be used in conjunction with SFDI for potential tumor imaging applications.

Leaf Area Index Estimation in Vineyards from Uav Hyperspectral Data, 2d Image Mosaics and 3d Canopy Surface Models

Science.gov (United States)

Kalisperakis, I.; Stentoumis, Ch.; Grammatikopoulos, L.; Karantzalos, K.

2015-08-01

The indirect estimation of leaf area index (LAI) in large spatial scales is crucial for several environmental and agricultural applications. To this end, in this paper, we compare and evaluate LAI estimation in vineyards from different UAV imaging datasets. In particular, canopy levels were estimated from i.e., (i) hyperspectral data, (ii) 2D RGB orthophotomosaics and (iii) 3D crop surface models. The computed canopy levels have been used to establish relationships with the measured LAI (ground truth) from several vines in Nemea, Greece. The overall evaluation indicated that the estimated canopy levels were correlated (r2 > 73%) with the in-situ, ground truth LAI measurements. As expected the lowest correlations were derived from the calculated greenness levels from the 2D RGB orthomosaics. The highest correlation rates were established with the hyperspectral canopy greenness and the 3D canopy surface models. For the later the accurate detection of canopy, soil and other materials in between the vine rows is required. All approaches tend to overestimate LAI in cases with sparse, weak, unhealthy plants and canopy.

Referenceless Prediction of Perceptual Fog Density and Perceptual Image Defogging.

Science.gov (United States)

Choi, Lark Kwon; You, Jaehee; Bovik, Alan Conrad

2015-11-01

We propose a referenceless perceptual fog density prediction model based on natural scene statistics (NSS) and fog aware statistical features. The proposed model, called Fog Aware Density Evaluator (FADE), predicts the visibility of a foggy scene from a single image without reference to a corresponding fog-free image, without dependence on salient objects in a scene, without side geographical camera information, without estimating a depth-dependent transmission map, and without training on human-rated judgments. FADE only makes use of measurable deviations from statistical regularities observed in natural foggy and fog-free images. Fog aware statistical features that define the perceptual fog density index derive from a space domain NSS model and the observed characteristics of foggy images. FADE not only predicts perceptual fog density for the entire image, but also provides a local fog density index for each patch. The predicted fog density using FADE correlates well with human judgments of fog density taken in a subjective study on a large foggy image database. As applications, FADE not only accurately assesses the performance of defogging algorithms designed to enhance the visibility of foggy images, but also is well suited for image defogging. A new FADE-based referenceless perceptual image defogging, dubbed DEnsity of Fog Assessment-based DEfogger (DEFADE) achieves better results for darker, denser foggy images as well as on standard foggy images than the state of the art defogging methods. A software release of FADE and DEFADE is available online for public use: http://live.ece.utexas.edu/research/fog/index.html.

The Carbon City Index (CCI)

DEFF Research Database (Denmark)

Boyd, Britta; Straatman, Bas; Mangalagiu, Diana

This paper presents a consumption-based Carbon City Index for CO2 emissions in a city. The index is derived from regional consumption and not from regional production. It includes imports and exports of emissions, factual emission developments, green investments as well as low carbon city...

A new index for electricity spot markets

International Nuclear Information System (INIS)

Falbo, Paolo; Fattore, Marco; Stefani, Silvana

2010-01-01

Different indexes are used in electricity markets worldwide to represent the daily behavior of spot prices. However, the peculiarities of these markets require a careful choice of the index, based on mathematical formulation and its statistical properties. Choosing a bad index may influence the financial policies of market players, since derivative pricing and hedging performance can be deeply affected. In this paper with an initial theoretical analysis, we intend to show that the most widely used indexes (simple arithmetic average and weighted average with current volumes) are poor representatives of the spot market. We will then perform an analysis of the hedging strategy on a derivative instrument (an Asian option) written on a reference index. The resulting simulations, applied to OMEL (Spain) and EEX (Germany), are sufficiently clear cut to suggest that the decision to adopt an index to represent properly a market must be taken very carefully. Finally we will propose a new index (FAST index) and, after comparing it with the previous indexes, will show that both theoretically and practically this index can be taken as a good electricity market synthetic indicator.

Differences in Gaussian diffusion tensor imaging and non-Gaussian diffusion kurtosis imaging model-based estimates of diffusion tensor invariants in the human brain.

Science.gov (United States)

Lanzafame, S; Giannelli, M; Garaci, F; Floris, R; Duggento, A; Guerrisi, M; Toschi, N

2016-05-01

An increasing number of studies have aimed to compare diffusion tensor imaging (DTI)-related parameters [e.g., mean diffusivity (MD), fractional anisotropy (FA), radial diffusivity (RD), and axial diffusivity (AD)] to complementary new indexes [e.g., mean kurtosis (MK)/radial kurtosis (RK)/axial kurtosis (AK)] derived through diffusion kurtosis imaging (DKI) in terms of their discriminative potential about tissue disease-related microstructural alterations. Given that the DTI and DKI models provide conceptually and quantitatively different estimates of the diffusion tensor, which can also depend on fitting routine, the aim of this study was to investigate model- and algorithm-dependent differences in MD/FA/RD/AD and anisotropy mode (MO) estimates in diffusion-weighted imaging of human brain white matter. The authors employed (a) data collected from 33 healthy subjects (20-59 yr, F: 15, M: 18) within the Human Connectome Project (HCP) on a customized 3 T scanner, and (b) data from 34 healthy subjects (26-61 yr, F: 5, M: 29) acquired on a clinical 3 T scanner. The DTI model was fitted to b-value =0 and b-value =1000 s/mm(2) data while the DKI model was fitted to data comprising b-value =0, 1000 and 3000/2500 s/mm(2) [for dataset (a)/(b), respectively] through nonlinear and weighted linear least squares algorithms. In addition to MK/RK/AK maps, MD/FA/MO/RD/AD maps were estimated from both models and both algorithms. Using tract-based spatial statistics, the authors tested the null hypothesis of zero difference between the two MD/FA/MO/RD/AD estimates in brain white matter for both datasets and both algorithms. DKI-derived MD/FA/RD/AD and MO estimates were significantly higher and lower, respectively, than corresponding DTI-derived estimates. All voxelwise differences extended over most of the white matter skeleton. Fractional differences between the two estimates [(DKI - DTI)/DTI] of most invariants were seen to vary with the invariant value itself as well as with MK

Atomic Force Microscopy Based Cell Shape Index

Science.gov (United States)

Adia-Nimuwa, Usienemfon; Mujdat Tiryaki, Volkan; Hartz, Steven; Xie, Kan; Ayres, Virginia

2013-03-01

Stellation is a measure of cell physiology and pathology for several cell groups including neural, liver and pancreatic cells. In the present work, we compare the results of a conventional two-dimensional shape index study of both atomic force microscopy (AFM) and fluorescent microscopy images with the results obtained using a new three-dimensional AFM-based shape index similar to sphericity index. The stellation of astrocytes is investigated on nanofibrillar scaffolds composed of electrospun polyamide nanofibers that has demonstrated promise for central nervous system (CNS) repair. Recent work by our group has given us the ability to clearly segment the cells from nanofibrillar scaffolds in AFM images. The clear-featured AFM images indicated that the astrocyte processes were longer than previously identified at 24h. It was furthermore shown that cell spreading could vary significantly as a function of environmental parameters, and that AFM images could record these variations. The new three-dimensional AFM-based shape index incorporates the new information: longer stellate processes and cell spreading. The support of NSF PHY-095776 is acknowledged.

Deriving soil function maps to assess related ecosystem services using imaging spectroscopy in the Lyss agricultural area, Switzerland

Science.gov (United States)

Diek, Sanne; de Jong, Rogier; Braun, Daniela; Böhler, Jonas; Schaepman, Michael

2014-05-01

Soils play an important role in the benefits offered by ecosystems services. In densely populated Switzerland soils are a scarce resource, with high pressure on services ranging from urban expansion to over-utilization. Key change drivers include erosion, soil degradation, land management change and (chemical) pollution, which should be taken into consideration. Therefore there is an emerging need for an integrated, sustainable and efficient system assessing the management of soil and land as a resource. The use of remote sensing can offer spatio-temporal and quantitative information of extended areas. In particular imaging spectroscopy has shown to perfectly complement existing sampling schemes as secondary information for digital soil mapping. Although only the upper-most layer of soil interacts with light when using reflectance spectroscopy, it still can offer valuable information that can be utilized by farmers and decision makers. Fully processed airborne imaging spectrometer data from APEX as well as land cover classification for the agricultural area in Lyss were available. Based on several spectral analysis methods we derived multiple soil properties, including soil organic matter, soil texture, and mineralogy; complemented by vegetation parameters, including leaf area index, chlorophyll content, pigment distribution, and water content. The surface variables were retrieved using a combination of index-based and physically-based retrievals. Soil properties in partly to fully vegetated areas were interpolated using regression kriging based methods. This allowed the continuous assessment of potential soil functions as well as non-contiguous maps of abundances of combined soil and vegetation parameters. Based on a simple regression model we could make a rough estimate of ecosystem services. This provided the opportunity to look at the differences between the interpolated soil function maps and the non-contiguous (but combined) vegetation and soil function maps

Evaluation of 18F-labeled icotinib derivatives as potential PET agents for tumor imaging

International Nuclear Information System (INIS)

Hongyu Ren; Hongyu Ning; Jin Chang; Mingxia Zhao; Yong He; Yan Chong; Chuanmin Qi

2016-01-01

In this study, three 18 F-labeled crown ether fused anilinoquinazoline derivatives ([ 18 F]11a-c) were synthesized and evaluated as potential tumor imaging probes. The biodistribution results of [ 18 F]11b were good. Compared with [ 18 F]-fludeoxyglucose and l-[ 18 F]-fluoroethyltyrosine in the same animal model, [ 18 F]11b had better tumor/brain, tumor/muscle, and tumor/blood uptake ratios. Overall, these results suggest that [ 18 F]11b is promising as a tumor imaging agent for positron emission tomography. (author)

Possible involvement of mitochondrial energy-producing ability in the development of right ventricular failure in monocrotaline-induced pulmonary hypertensive rats.

Science.gov (United States)

Daicho, Takuya; Yagi, Tatsuya; Abe, Yohei; Ohara, Meiko; Marunouchi, Tetsuro; Takeo, Satoshi; Tanonaka, Kouichi

2009-09-01

The present study was undertaken to explore the possible involvement of alterations in the mitochondrial energy-producing ability in the development of the right ventricular failure in monocrotaline-administered rats. The rats at the 6th week after subcutaneous injection of 60 mg/kg monocrotaline revealed marked myocardial hypertrophy and fibrosis, that is, severe cardiac remodeling. The time-course study on the cardiac hemodynamics of the monocrotaline-administered rat by the cannula and echocardiographic methods showed a reduction in cardiac double product, a decrease in cardiac output index, and an increase in the right ventricular Tei index, suggesting that the right ventricular failure was induced at the 6th week after monocrotaline administration in rats. The mitochondrial oxygen consumption rate of the right ventricular muscle isolated from the monocrotaline-administered animal was decreased, which was associated with a reduction in myocardial high-energy phosphates. Furthermore, the decrease in mitochondrial oxygen consumption rate was inversely related to the increase in the right ventricular Tei index of the monocrotaline-administered rats. These results suggest that impairment of the mitochondrial energy-producing ability is involved in the development of the right ventricular failure in monocrotaline-induced pulmonary hypertensive rats.

A Consistent Pricing Model for Index Options and Volatility Derivatives

DEFF Research Database (Denmark)

Cont, Rama; Kokholm, Thomas

observed properties of variance swap dynamics and allows for jumps in volatility and returns. An affine specification using L´evy processes as building blocks leads to analytically tractable pricing formulas for options on variance swaps as well as efficient numerical methods for pricing of European......We propose and study a flexible modeling framework for the joint dynamics of an index and a set of forward variance swap rates written on this index, allowing options on forward variance swaps and options on the underlying index to be priced consistently. Our model reproduces various empirically...... options on the underlying asset. The model has the convenient feature of decoupling the vanilla skews from spot/volatility correlations and allowing for different conditional correlations in large and small spot/volatility moves. We show that our model can simultaneously fit prices of European options...

A Preserved Context Indexing System for Microcomputers: PERMDEX.

Science.gov (United States)

Yerkey, A. Neil

1983-01-01

Following a discussion of derivative versus assignment indexing, use of roles, and concept behind Preserved Concept Indexing System, features of PERMDEX (microcomputer program to assist in creation of permuted printed index) are described including indexer input and prompts, the shunting algorithm, and sorting and printing routines. Fourteen…

Bounds and inequalities relating h-index, g-index, e-index and generalized impact factor: an improvement over existing models.

Science.gov (United States)

Abbas, Ash Mohammad

2012-01-01

In this paper, we describe some bounds and inequalities relating h-index, g-index, e-index, and generalized impact factor. We derive the bounds and inequalities relating these indexing parameters from their basic definitions and without assuming any continuous model to be followed by any of them. We verify the theorems using citation data for five Price Medalists. We observe that the lower bound for h-index given by Theorem 2, [formula: see text], g ≥ 1, comes out to be more accurate as compared to Schubert-Glanzel relation h is proportional to C(2/3)P(-1/3) for a proportionality constant of 1, where C is the number of citations and P is the number of papers referenced. Also, the values of h-index obtained using Theorem 2 outperform those obtained using Egghe-Liang-Rousseau power law model for the given citation data of Price Medalists. Further, we computed the values of upper bound on g-index given by Theorem 3, g ≤ (h + e), where e denotes the value of e-index. We observe that the upper bound on g-index given by Theorem 3 is reasonably tight for the given citation record of Price Medalists.

Integration of biological responses from a suite of bioassays for the Venice Lagoon (Italy) through sediment toxicity index - Part A: Development and comparison of two methodological approaches

International Nuclear Information System (INIS)

Losso, Chiara; Novelli, Alessandra Arizzi; De Salvador, Davide; Ghetti, Pier Francesco; Ghirardini, Annamaria Volpi

2010-01-01

Marine and coastal quality assessment, based on test batteries involving a wide array of endpoints, organisms and test matrices, needs for setting up toxicity indices that integrate multiple toxicological measures for decision-making processes and that classify the continuous toxicity response into discrete categories according to the European Water Framework Directive. Two toxicity indices were developed for the lagoon environment such as the Venice Lagoon. Stepwise procedure included: the construction of a database that identified test-matrix pairs (indicators); the selection of a minimum number of ecotoxicological indicators, called toxicological core metrics (CMs-tox) on the basis of specific criteria; the development of toxicity scores for each CM-tox; the integration of the CMs-tox into two indices, the Toxicity Effect Index (TEI), based on the transformation of Toxic Unit (TU) data that were integrated as logarithmic sum, and the Weighted Average Toxicity Index (WATI), starting from toxicity classes integrated as weighted mean. Results from the indices are compared; advantages and drawbacks of both approaches are discussed. - Two toxicity indices were set up and compared to integrate toxicity data from a battery of bioassays for the Venice lagoon.

Integration of biological responses from a suite of bioassays for the Venice Lagoon (Italy) through sediment toxicity index - Part A: Development and comparison of two methodological approaches

Energy Technology Data Exchange (ETDEWEB)

Losso, Chiara, E-mail: closso@unive.i [Environmental Sciences Department, University Ca' Foscari of Venice, Campo della Celestia 2737/b, I-30122 Venice (Italy); Novelli, Alessandra Arizzi [Environmental Sciences Department, University Ca' Foscari of Venice, Campo della Celestia 2737/b, I-30122 Venice (Italy); De Salvador, Davide [Physics Department, Padova University, via Marzolo 8, 35131 Padova (Italy); Ghetti, Pier Francesco; Ghirardini, Annamaria Volpi [Environmental Sciences Department, University Ca' Foscari of Venice, Campo della Celestia 2737/b, I-30122 Venice (Italy)

2010-12-15

Marine and coastal quality assessment, based on test batteries involving a wide array of endpoints, organisms and test matrices, needs for setting up toxicity indices that integrate multiple toxicological measures for decision-making processes and that classify the continuous toxicity response into discrete categories according to the European Water Framework Directive. Two toxicity indices were developed for the lagoon environment such as the Venice Lagoon. Stepwise procedure included: the construction of a database that identified test-matrix pairs (indicators); the selection of a minimum number of ecotoxicological indicators, called toxicological core metrics (CMs-tox) on the basis of specific criteria; the development of toxicity scores for each CM-tox; the integration of the CMs-tox into two indices, the Toxicity Effect Index (TEI), based on the transformation of Toxic Unit (TU) data that were integrated as logarithmic sum, and the Weighted Average Toxicity Index (WATI), starting from toxicity classes integrated as weighted mean. Results from the indices are compared; advantages and drawbacks of both approaches are discussed. - Two toxicity indices were set up and compared to integrate toxicity data from a battery of bioassays for the Venice lagoon.

Captura de Rhynchophorus palmarum L. (Coleoptera: curculionidae em armadilhas iscadas com o feromônio de agregação e compostos voláteis de frutos do abacaxi Trap catches of Rhynchophorus palmarum L. (Coleoptera: curculionidae baited with its aggregation pheromone and volatile compounds from pineapple

Directory of Open Access Journals (Sweden)

Adriana Guimarães Duarte

2003-04-01

Full Text Available O objetivo deste trabalho foi determinar os índices de captura de Rhynchophorus palmarum em armadilhas iscadas com o feromônio de agregação, 6-metil-2(E-hepten-4-ol (rincoforol, associado a toletes de cana-de-açúcar, a pedaços de frutos do abacaxi e a seis compostos voláteis isolados de frutos do abacaxi. Os compostos voláteis do abacaxi são caracterizados por uma mistura de ésteres metílicos e etílicos, sendo o octanoato de metila e o octanoato de etila os mais abundantes. As armadilhas iscadas com o rincoforol associado a toletes de cana-de-açúcar e as iscas com rincoforol associado a pedaços de abacaxi não apresentaram diferenças significativas no número de besouros capturados. No entanto, ambas apresentaram índices de captura superiores àquelas em que o rincoforol foi utilizado em associação com voláteis do abacaxi. Não se observaram efeitos significativos do local e época de captura, nem no número de machos e de fêmeas capturados.The aim of this work was to investigate the capture of Rhynchophorus palmarum in traps baited with its aggregation pheromone, 6-methyl-2(E-hepten-4-ol (rhynchophorol, in association with sugar cane, pieces of pineapple fruit, and six volatile compounds from pineapple. A mixture of methyl and ethyl esters, being methyl octanoate and ethyl octanoate the most abundant, characterizes the volatile compounds from pineapple fruits. Traps baited with rhynchophorol in association with sugar cane and those baited with rhynchophorol in association with pieces of pineapple, showed no significant differences in the number of trapped weevils. However, both traps caught significantly more weevils, than those baited with rhynchophorol in association with pineapple volatiles. There were no significant effects from place and time or in the number of male and female weevils trapped.

WE-G-207-06: 3D Fluoroscopic Image Generation From Patient-Specific 4DCBCT-Based Motion Models Derived From Physical Phantom and Clinical Patient Images

International Nuclear Information System (INIS)

Dhou, S; Cai, W; Hurwitz, M; Rottmann, J; Myronakis, M; Cifter, F; Berbeco, R; Lewis, J; Williams, C; Mishra, P; Ionascu, D

2015-01-01

Purpose: Respiratory-correlated cone-beam CT (4DCBCT) images acquired immediately prior to treatment have the potential to represent patient motion patterns and anatomy during treatment, including both intra- and inter-fractional changes. We develop a method to generate patient-specific motion models based on 4DCBCT images acquired with existing clinical equipment and used to generate time varying volumetric images (3D fluoroscopic images) representing motion during treatment delivery. Methods: Motion models are derived by deformably registering each 4DCBCT phase to a reference phase, and performing principal component analysis (PCA) on the resulting displacement vector fields. 3D fluoroscopic images are estimated by optimizing the resulting PCA coefficients iteratively through comparison of the cone-beam projections simulating kV treatment imaging and digitally reconstructed radiographs generated from the motion model. Patient and physical phantom datasets are used to evaluate the method in terms of tumor localization error compared to manually defined ground truth positions. Results: 4DCBCT-based motion models were derived and used to generate 3D fluoroscopic images at treatment time. For the patient datasets, the average tumor localization error and the 95th percentile were 1.57 and 3.13 respectively in subsets of four patient datasets. For the physical phantom datasets, the average tumor localization error and the 95th percentile were 1.14 and 2.78 respectively in two datasets. 4DCBCT motion models are shown to perform well in the context of generating 3D fluoroscopic images due to their ability to reproduce anatomical changes at treatment time. Conclusion: This study showed the feasibility of deriving 4DCBCT-based motion models and using them to generate 3D fluoroscopic images at treatment time in real clinical settings. 4DCBCT-based motion models were found to account for the 3D non-rigid motion of the patient anatomy during treatment and have the potential

Natural Resource Management Index (NRMI), 2011 Release

Data.gov (United States)

National Aeronautics and Space Administration — The Natural Resource Management Index (NRMI), 2011 Release is a composite index for 174 countries derived from the average of four proximity-to-target indicators for...

Natural Resource Management Index (NRMI), 2010 Release

Data.gov (United States)

National Aeronautics and Space Administration — The Natural Resource Management Index (NRMI), 2010 Release is a composite index for 157 countries derived from the average of four proximity-to-target indicators for...

Natural Resource Management Index (NRMI), 2010 Release

Data.gov (United States)

National Aeronautics and Space Administration — The Natural Resource Management Index (NRMI), 2011 Release is a composite index for 174 countries derived from the average of four proximity-to-target indicators for...

Natural Resource Management Index (NRMI), 2009 Release

Data.gov (United States)

National Aeronautics and Space Administration — The Natural Resource Management Index (NRMI), 2009 Release is a composite index for 171 countries derived from the average of four proximity-to-target indicators for...

Caracterização e extração de compostos voláteis de resíduos do processamento de maracujá (Passiflora edulis Sims f. flavicarpa degener Characterization and extraction of volatile compounds from passion fruit (Passiflora edulis Sims f. flavicarpa degener processing waste

Directory of Open Access Journals (Sweden)

Lília Calheiros de Oliveira

2012-12-01

Full Text Available Este estudo objetivou extrair e identificar compostos voláteis presentes nos resíduos de processo de maracujá. Obtiveram-se destilados a partir de resíduos de maracujá através das técnicas de hidrodestilação simples e hidrodestilação com arraste de gás nitrogênio. Os compostos voláteis presentes nos destilados foram capturados por microextração em fase sólida, empregando-se fibra Carboxen/DVB/DMS, e identificados por cromatografia gasosa acoplada com espectrômetro de massa, usando a coluna capilar de sílica fundida CP WAX 52. Foram identificados trinta e um compostos voláteis no extrato obtido pela técnica de hidrodestilação simples, sendo os principais compostos: neral (26,19%, cinamato de metila (18,52%, linalol (16,82%, 1-undecanol (5,60%, cis-óxido de linalol (4,41%, benzaldeído (3,92% e 1-hexanol (3,48%. Para a hidrodestilação com arraste de gás nitrogênio, trinta compostos foram identificados, sendo que, em maior porcentagem de área, destacaram-se: cinamato de metila (30,41%, neral (24,46%, β-ionona (13,81%, linalol (4,0% e acido butanoico (2,19%. O presente estudo revelou que os resíduos de maracujá apresentam compostos voláteis que podem ser extraídos na forma de aromas, apresentando potencial para gerar essências naturais com valor agregado.The aim of this study was to extract and identify volatile compounds from passion fruit residues generated during processing. Distillates of passion fruit residues were obtained from the techniques of simple hydrodistillation and hydrodistillation by passing nitrogen gas. The volatile compounds present in the distillates were captured by solid phase microextraction with Carboxen/DVB/DMS fiber. The volatile compounds were indentified by gas chromatography with mass spectrometry using a fused sillica capillary column with a CP WAX 52 stationary phase. Thirty one compounds were indentified by simple hydrodistillation technique. The main compounds were: neral (26

Image quality of digital mammography images produced using wet and dry laser imaging systems

International Nuclear Information System (INIS)

Al Khalifah, K.; Brindhaban, A.; AlArfaj, R.; Jassim, O.

2006-01-01

Introduction: A study was carried out to compare the quality of digital mammographic images printed or processed by a wet laser imaging system and a dedicated mammographic dry laser imaging system. Material and methods: Digital images of a tissue equivalent breast phantom were obtained using a GE Senographe 2000D digital mammography system and different target/filter combinations of the X-ray tube. These images were printed on films using the Fuji FL-IM D wet laser imaging system and the Kodak DryView 8600 dry laser imaging system. The quality of images was assessed in terms of detectability of microcalcifications and simulated tumour masses by five radiologists. In addition, the contrast index and speed index of the two systems were measured using the step wedge in the phantom. The unpaired, unequal variance t-test was used to test any statistically significant differences. Results: There were no significant (p < 0.05) differences between the images printed using the two systems in terms of microcalcification and tumour mass detectability. The wet system resulted in slightly higher contrast index while the dry system showed significantly higher speed index. Conclusion: Both wet and dry laser imaging systems can produce mammography images of good quality on which 0.2 mm microcalcifications and 2 mm tumour masses can be detected. Dry systems are preferable due to the absence of wet chemical processing and solid or liquid chemical waste. The wet laser imaging systems, however, still represent a useful alternative to dry laser imaging systems for mammography studies

Image-derived and arterial blood sampled input functions for quantitative PET imaging of the angiotensin II subtype 1 receptor in the kidney

Energy Technology Data Exchange (ETDEWEB)

Feng, Tao; Tsui, Benjamin M. W.; Li, Xin; Vranesic, Melin; Lodge, Martin A.; Gulaldi, Nedim C. M.; Szabo, Zsolt, E-mail: zszabo@jhmi.edu [Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins School of Medicine, Baltimore, Maryland 21287 (United States)

2015-11-15

Purpose: The radioligand {sup 11}C-KR31173 has been introduced for positron emission tomography (PET) imaging of the angiotensin II subtype 1 receptor in the kidney in vivo. To study the biokinetics of {sup 11}C-KR31173 with a compartmental model, the input function is needed. Collection and analysis of arterial blood samples are the established approach to obtain the input function but they are not feasible in patients with renal diseases. The goal of this study was to develop a quantitative technique that can provide an accurate image-derived input function (ID-IF) to replace the conventional invasive arterial sampling and test the method in pigs with the goal of translation into human studies. Methods: The experimental animals were injected with [{sup 11}C]KR31173 and scanned up to 90 min with dynamic PET. Arterial blood samples were collected for the artery derived input function (AD-IF) and used as a gold standard for ID-IF. Before PET, magnetic resonance angiography of the kidneys was obtained to provide the anatomical information required for derivation of the recovery coefficients in the abdominal aorta, a requirement for partial volume correction of the ID-IF. Different image reconstruction methods, filtered back projection (FBP) and ordered subset expectation maximization (OS-EM), were investigated for the best trade-off between bias and variance of the ID-IF. The effects of kidney uptakes on the quantitative accuracy of ID-IF were also studied. Biological variables such as red blood cell binding and radioligand metabolism were also taken into consideration. A single blood sample was used for calibration in the later phase of the input function. Results: In the first 2 min after injection, the OS-EM based ID-IF was found to be biased, and the bias was found to be induced by the kidney uptake. No such bias was found with the FBP based image reconstruction method. However, the OS-EM based image reconstruction was found to reduce variance in the subsequent

Spatial and radiometric characterization of multi-spectrum satellite images through multi-fractal analysis

Science.gov (United States)

Alonso, Carmelo; Tarquis, Ana M.; Zúñiga, Ignacio; Benito, Rosa M.

2017-03-01

Several studies have shown that vegetation indexes can be used to estimate root zone soil moisture. Earth surface images, obtained by high-resolution satellites, presently give a lot of information on these indexes, based on the data of several wavelengths. Because of the potential capacity for systematic observations at various scales, remote sensing technology extends the possible data archives from the present time to several decades back. Because of this advantage, enormous efforts have been made by researchers and application specialists to delineate vegetation indexes from local scale to global scale by applying remote sensing imagery. In this work, four band images have been considered, which are involved in these vegetation indexes, and were taken by satellites Ikonos-2 and Landsat-7 of the same geographic location, to study the effect of both spatial (pixel size) and radiometric (number of bits coding the image) resolution on these wavelength bands as well as two vegetation indexes: the Normalized Difference Vegetation Index (NDVI) and the Enhanced Vegetation Index (EVI). In order to do so, a multi-fractal analysis of these multi-spectral images was applied in each of these bands and the two indexes derived. The results showed that spatial resolution has a similar scaling effect in the four bands, but radiometric resolution has a larger influence in blue and green bands than in red and near-infrared bands. The NDVI showed a higher sensitivity to the radiometric resolution than EVI. Both were equally affected by the spatial resolution. From both factors, the spatial resolution has a major impact in the multi-fractal spectrum for all the bands and the vegetation indexes. This information should be taken in to account when vegetation indexes based on different satellite sensors are obtained.

High-resolution imaging of cellular processes across textured surfaces using an indexed-matched elastomer.

Science.gov (United States)

Ravasio, Andrea; Vaishnavi, Sree; Ladoux, Benoit; Viasnoff, Virgile

2015-03-01

Understanding and controlling how cells interact with the microenvironment has emerged as a prominent field in bioengineering, stem cell research and in the development of the next generation of in vitro assays as well as organs on a chip. Changing the local rheology or the nanotextured surface of substrates has proved an efficient approach to improve cell lineage differentiation, to control cell migration properties and to understand environmental sensing processes. However, introducing substrate surface textures often alters the ability to image cells with high precision, compromising our understanding of molecular mechanisms at stake in environmental sensing. In this paper, we demonstrate how nano/microstructured surfaces can be molded from an elastomeric material with a refractive index matched to the cell culture medium. Once made biocompatible, contrast imaging (differential interference contrast, phase contrast) and high-resolution fluorescence imaging of subcellular structures can be implemented through the textured surface using an inverted microscope. Simultaneous traction force measurements by micropost deflection were also performed, demonstrating the potential of our approach to study cell-environment interactions, sensing processes and cellular force generation with unprecedented resolution. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

MODIS-derived daily PAR simulation from cloud-free images and its validation

Energy Technology Data Exchange (ETDEWEB)

Chen, Liangfu; Gu, Xingfa; Tian, Guoliang [State Key Laboratory of Remote Sensing Science, Jointly Sponsored by Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University, Beijing 100101 (China); The Center for National Spaceborne Demonstration, Beijing 100101 (China); Gao, Yanhua [State Key Laboratory of Remote Sensing Science, Jointly Sponsored by Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University, Beijing 100101 (China); Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101 (China); Yang, Lei [State Key Laboratory of Remote Sensing Science, Jointly Sponsored by Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University, Beijing 100101 (China); Jilin University, Changchun 130026 (China); Liu, Qinhuo [State Key Laboratory of Remote Sensing Science, Jointly Sponsored by Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University, Beijing 100101 (China)

2008-06-15

In this paper, a MODIS-derived daily PAR (photosynthetically active radiation) simulation model from cloud-free image over land surface has been developed based on Bird and Riordan's model. In this model, the total downwelling spectral surface irradiance is divided into two parts: one is beam irradiance, and another is diffuse irradiance. The attenuation of solar beam irradiance comprises scattering by the gas mixture, absorption by ozone, the gas mixture and water vapor, and scattering and absorption by aerosols. The diffuse irradiance is scattered out of the direct beam and towards the surface. The multiple ground-air interactions have been taken into account in the diffuse irradiance model. The parameters needed in this model are atmospheric water vapor content, aerosol optical thickness and spectral albedo ranging from 400 nm to 700 nm. They are all retrieved from MODIS data. Then, the instantaneous photosynthetically available radiation (IPAR) is integrated by using a weighted sum at each of the visible MODIS wavebands. Finally, a daily PAR is derived by integration of IPAR. In order to validate the MODIS-derived PAR model, we compared the field PAR measurements in 2003 and 2004 against the simulated PAR. The measurements were made at the Qianyanzhou ecological experimental station, Chinese Ecosystem Research Network. A total of 54 days of cloud-free MODIS L1B level images were used for the PAR simulation. Our results show that the simulated PAR is consistent with field measurements, where the correlation coefficient of linear regression between calculated PAR and measured PAR is 0.93396. However, there were some uncertainties in the comparison of 1 km pixel PAR with the tower flux stand measurement. (author)

Gold-carbon dots for the intracellular imaging of cancer-derived exosomes

Science.gov (United States)

Jiang, Xiaoyue; Zong, Shenfei; Chen, Chen; Zhang, Yizhi; Wang, Zhuyuan; Cui, Yiping

2018-04-01

As a novel fluorescent nanomaterial, gold-carbon quantum dots (GCDs) possess high biocompatibility and can be easily synthesized by a microwave-assisted method. Owing to their small sizes and unique optical properties, GCDs can be applied to imaging of biological targets, such as cells, exosomes and other organelles. In this study, GCDs were used for fluorescence imaging of exosomes. Tumor-specific antibodies are attached to the GCDs, forming exosome specific nanoprobes. The nanoprobes can label exosomes via immuno-reactions and thus facilitate fluorescent imaging of exosomes. When incubated with live cells, exosomes labeled with the nanoprobes can be taken up by the cells. The intracellular experiments confirmed that the majority of exosomes were endocytosed by cells and transported to lysosomes. The manner by which exosomes were taken up and the intracellular distribution of exosomes are unaffected by the GCDs. The experimental results successfully demonstrated that the presented nanoprobe can be used to study the intrinsic intracellular behavior of tumor derived exosomes. We believe that the GCDs based nanoprobe holds a great promise in the study of exosome related cellular events, such as cancer metastasis.

Self-compassion moderates the relationship between body mass index and both eating disorder pathology and body image flexibility.

Science.gov (United States)

Kelly, Allison C; Vimalakanthan, Kiruthiha; Miller, Kathryn E

2014-09-01

The current study examined whether self-compassion, the tendency to treat oneself kindly during distress and disappointments, would attenuate the positive relationship between body mass index (BMI) and eating disorder pathology, and the negative relationship between BMI and body image flexibility. One-hundred and fifty-three female undergraduate students completed measures of self-compassion, self-esteem, eating disorder pathology, and body image flexibility, which refers to one's acceptance of negative body image experiences. Controlling for self-esteem, hierarchical regressions revealed that self-compassion moderated the relationships between BMI and the criteria. Specifically, the positive relationship between BMI and eating disorder pathology and the negative relationship between BMI and body image flexibility were weaker the higher women's levels of self-compassion. Among young women, self-compassion may help to protect against the greater eating disturbances that coincide with a higher BMI, and may facilitate the positive body image experiences that tend to be lower the higher one's BMI. Copyright © 2014 Elsevier Ltd. All rights reserved.

Improved SAR Amplitude Image Offset Measurements for Deriving Three-Dimensional Coseismic Displacements

KAUST Repository

Wang, Teng; Jonsson, Sigurjon

2015-01-01

Offsets of synthetic aperture radar (SAR) images have played an important role in deriving complete three-dimensional (3-D) surface displacement fields in geoscientific applications. However, offset maps often suffer from multiple outliers and patch-like artifacts, because the standard offset-measurement method is a regular moving-window operation that does not consider the scattering characteristics of the ground. Here, we show that by focusing the offset measurements on predetected strong reflectors, the reliability and accuracy of SAR offsets can be significantly improved. Application to the 2011 Van (Turkey) earthquake reveals a clear deformation signal from an otherwise decorrelated interferogram, making derivation of the 3-D coseismic displacement field possible. Our proposed method can improve mapping of coseismic deformation and other ground displacements, such as glacier flow and landslide movement when strong reflectors exist.

Improved SAR Amplitude Image Offset Measurements for Deriving Three-Dimensional Coseismic Displacements

KAUST Repository

Wang, Teng

2015-02-03

Offsets of synthetic aperture radar (SAR) images have played an important role in deriving complete three-dimensional (3-D) surface displacement fields in geoscientific applications. However, offset maps often suffer from multiple outliers and patch-like artifacts, because the standard offset-measurement method is a regular moving-window operation that does not consider the scattering characteristics of the ground. Here, we show that by focusing the offset measurements on predetected strong reflectors, the reliability and accuracy of SAR offsets can be significantly improved. Application to the 2011 Van (Turkey) earthquake reveals a clear deformation signal from an otherwise decorrelated interferogram, making derivation of the 3-D coseismic displacement field possible. Our proposed method can improve mapping of coseismic deformation and other ground displacements, such as glacier flow and landslide movement when strong reflectors exist.

Physics of negative refractive index materials

International Nuclear Information System (INIS)

Ramakrishna, S Anantha

2005-01-01

In the past few years, new developments in structured electromagnetic materials have given rise to negative refractive index materials which have both negative dielectric permittivity and negative magnetic permeability in some frequency ranges. The idea of a negative refractive index opens up new conceptual frontiers in photonics. One much-debated example is the concept of a perfect lens that enables imaging with sub-wavelength image resolution. Here we review the fundamental concepts and ideas of negative refractive index materials. First we present the ideas of structured materials or meta-materials that enable the design of new materials with a negative dielectric permittivity, negative magnetic permeability and negative refractive index. We discuss how a variety of resonance phenomena can be utilized to obtain these materials in various frequency ranges over the electromagnetic spectrum. The choice of the wave-vector in negative refractive index materials and the issues of dispersion, causality and energy transport are analysed. Various issues of wave propagation including nonlinear effects and surface modes in negative refractive materials (NRMs) are discussed. In the latter part of the review, we discuss the concept of a perfect lens consisting of a slab of a NRM. This perfect lens can image the far-field radiative components as well as the near-field evanescent components, and is not subject to the traditional diffraction limit. Different aspects of this lens such as the surface modes acting as the mechanism for the imaging of the evanescent waves, the limitations imposed by dissipation and dispersion in the negative refractive media, the generalization of this lens to optically complementary media and the possibility of magnification of the near-field images are discussed. Recent experimental developments verifying these ideas are briefly covered

TOMS Absorbing Aerosol Index

Data.gov (United States)

Washington University St Louis — TOMS_AI_G is an aerosol related dataset derived from the Total Ozone Monitoring Satellite (TOMS) Sensor. The TOMS aerosol index arises from absorbing aerosols such...

Image retrieval

DEFF Research Database (Denmark)

Ørnager, Susanne

1997-01-01

The paper touches upon indexing and retrieval for effective searches of digitized images. Different conceptions of what subject indexing means are described as a basis for defining an operational subject indexing strategy for images. The methodology is based on the art historian Erwin Panofsky......), special knowledge about image codes, and special knowledge about history of ideas. The semiologist Roland Barthes has established a semiology for pictorial expressions based on advertising photos. Barthes uses the concepts denotation/connotation where denotations can be explained as the sober expression...

Testing non-rigid registration of nuclear medicine data using synthetic derived SPECT images

International Nuclear Information System (INIS)

Todd-Pokropek, A.

2002-01-01

Aim: Non-rigid registration is needed to build atlas data to make statistical tests of significance of uptake in nuclear medicine (NM). Non-rigid registration is much more difficult than rigid registration to validate since some kind of matching function must be defined throughout the volume being registered, and no suitable gold standards exist. The aim here has been to assess non-rigid methods of registration and deformation for NM to NM and NM to MRI data. An additional aim has been to derive good synthetic SPECT images from other NM and MRI data to be used after as reference standards. Material and Methods: Phantom and patient test images have been acquired for both NM and MRI, which are then used to generate projections, where the characteristics of the images are modified to change both signal and noise properties. These derived images are different in character but perfectly registered with the original data, and can then be deformed in a known manner. The registration algorithm is then run backwards to re-register the modified deformed data with the original images. A technique has been developed to assess the vector fields of the original deformation to the reverse non-rigid registration field. Results: The main purpose of this paper is to describe a methodology for optimising algorithms, not to develop the algorithms themselves. Two different algorithms based on optic flow and thin plate spline interpolation have been intercompared and in particular the constraints imposed tested. Considerable differences in matching can be observed in different regions for example edge and centre of brain. Conclusions: Quadratic distance between known makers is a bad estimate to use to assess non-rigid registration. A robust statistic has been developed which can be used to optimise non-rigid algorithms based on the use of synthetic SPECT reference datasets. While the task being tested is simpler than the real clinical task, it is the first essential step in the

Study of an image-derived SUV and a modified SUV using mouse FDG-PET

Energy Technology Data Exchange (ETDEWEB)

Zheng Xiujuan, E-mail: zhengxj@eie.polyu.edu.h [Department of Electronic Information Engineering, the Hong Kong Polytechnic University, Hung Hom, Kowloon (Hong Kong); Yu, Chin-Lung; Sha Wei; Radu, Caius; Huang, Sung-Cheng [Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, University of California Los Angeles, CA (United States); Feng Dagan [Department of Electronic Information Engineering, the Hong Kong Polytechnic University, Hung Hom, Kowloon (Hong Kong); School of Information Technologies, the University of Sydney, Sydney (Australia)

2011-04-15

Introduction: Standard uptake value (SUV) is calculated without consideration of the differences in plasma 2-deoxy-2-[18F]fluoro-D-glucose (FDG) clearance. Its variability can be affected by changes of the amount of excreted FDG by renal function. Moreover, the estimation of SUV is quite sensitive to errors in the measurements of body weight and injected dose. This study aims to develop an image-based method to obtain an image-derived SUV (iSUV) and a modified SUV (mSUV) to overcome these problems. Methods: Thirty-one tumor-planted SCID mice were scanned in micro-positron emission tomography (PET) at {approx}60 min post FDG injection and then scanned in micro-computed tomographic (CT). Using image-based method, the body weight and injected dose were derived from the microPET/CT images to calculate iSUV. The volumes and the total activities of FDG within the bladder and the whole-body were also obtained to calculate mSUV. For the selected targets, the iSUVs and mSUVs were compared against their corresponding SUVs. Results: Compared with SUV factor (injected dose/body weight), iSUV factor had an average percentage error of -0.7%. The linear regressions between SUV and iSUV had a slope of 0.99 with correlation coefficient of 0.95. Compared with SUV and iSUV, coefficient of variation of mSUV decreased while the tumor-to-background separation of mSUV increased. Conclusions: Using this image-based method, the iSUV can replace SUV when the actual measurements were missing or unreliable. The mSUV can reduce the inter-subject variability and enhance the tumor-to-background separation in mouse FDG-PET studies.

Study of an image-derived SUV and a modified SUV using mouse FDG-PET

International Nuclear Information System (INIS)

Zheng Xiujuan; Yu, Chin-Lung; Sha Wei; Radu, Caius; Huang, Sung-Cheng; Feng Dagan

2011-01-01

Introduction: Standard uptake value (SUV) is calculated without consideration of the differences in plasma 2-deoxy-2-[18F]fluoro-D-glucose (FDG) clearance. Its variability can be affected by changes of the amount of excreted FDG by renal function. Moreover, the estimation of SUV is quite sensitive to errors in the measurements of body weight and injected dose. This study aims to develop an image-based method to obtain an image-derived SUV (iSUV) and a modified SUV (mSUV) to overcome these problems. Methods: Thirty-one tumor-planted SCID mice were scanned in micro-positron emission tomography (PET) at ∼60 min post FDG injection and then scanned in micro-computed tomographic (CT). Using image-based method, the body weight and injected dose were derived from the microPET/CT images to calculate iSUV. The volumes and the total activities of FDG within the bladder and the whole-body were also obtained to calculate mSUV. For the selected targets, the iSUVs and mSUVs were compared against their corresponding SUVs. Results: Compared with SUV factor (injected dose/body weight), iSUV factor had an average percentage error of -0.7%. The linear regressions between SUV and iSUV had a slope of 0.99 with correlation coefficient of 0.95. Compared with SUV and iSUV, coefficient of variation of mSUV decreased while the tumor-to-background separation of mSUV increased. Conclusions: Using this image-based method, the iSUV can replace SUV when the actual measurements were missing or unreliable. The mSUV can reduce the inter-subject variability and enhance the tumor-to-background separation in mouse FDG-PET studies.

Composite Match Index with Application of Interior Deformation Field Measurement from Magnetic Resonance Volumetric Images of Human Tissues

Directory of Open Access Journals (Sweden)

Penglin Zhang

2012-01-01

Full Text Available Whereas a variety of different feature-point matching approaches have been reported in computer vision, few feature-point matching approaches employed in images from nonrigid, nonuniform human tissues have been reported. The present work is concerned with interior deformation field measurement of complex human tissues from three-dimensional magnetic resonance (MR volumetric images. To improve the reliability of matching results, this paper proposes composite match index (CMI as the foundation of multimethod fusion methods to increase the reliability of these various methods. Thereinto, we discuss the definition, components, and weight determination of CMI. To test the validity of the proposed approach, it is applied to actual MR volumetric images obtained from a volunteer’s calf. The main result is consistent with the actual condition.

Document image database indexing with pictorial dictionary

Science.gov (United States)

Akbari, Mohammad; Azimi, Reza

2010-02-01

In this paper we introduce a new approach for information retrieval from Persian document image database without using Optical Character Recognition (OCR).At first an attribute called subword upper contour label is defined then, a pictorial dictionary is constructed based on this attribute for the subwords. By this approach we address two issues in document image retrieval: keyword spotting and retrieval according to the document similarities. The proposed methods have been evaluated on a Persian document image database. The results have proved the ability of this approach in document image information retrieval.

Effective Five Directional Partial Derivatives-Based Image Smoothing and a Parallel Structure Design.

Science.gov (United States)

Choongsang Cho; Sangkeun Lee

2016-04-01

Image smoothing has been used for image segmentation, image reconstruction, object classification, and 3D content generation. Several smoothing approaches have been used at the pre-processing step to retain the critical edge, while removing noise and small details. However, they have limited performance, especially in removing small details and smoothing discrete regions. Therefore, to provide fast and accurate smoothing, we propose an effective scheme that uses a weighted combination of the gradient, Laplacian, and diagonal derivatives of a smoothed image. In addition, to reduce computational complexity, we designed and implemented a parallel processing structure for the proposed scheme on a graphics processing unit (GPU). For an objective evaluation of the smoothing performance, the images were linearly quantized into several layers to generate experimental images, and the quantized images were smoothed using several methods for reconstructing the smoothly changed shape and intensity of the original image. Experimental results showed that the proposed scheme has higher objective scores and better successful smoothing performance than similar schemes, while preserving and removing critical and trivial details, respectively. For computational complexity, the proposed smoothing scheme running on a GPU provided 18 and 16 times lower complexity than the proposed smoothing scheme running on a CPU and the L0-based smoothing scheme, respectively. In addition, a simple noise reduction test was conducted to show the characteristics of the proposed approach; it reported that the presented algorithm outperforms the state-of-the art algorithms by more than 5.4 dB. Therefore, we believe that the proposed scheme can be a useful tool for efficient image smoothing.

Asmens duomenų apsaugos ir žodžio laisvės konfliktas elektroninėje viešojoje erdvėje. Teisės būti pamirštam atvejis

OpenAIRE

Maslauskaitė, Judita

2018-01-01

Žodžio laisvė yra viena iš bene seniausiai pripažintų ir konstituciškai saugomų fundamentalių žmogaus teisių pasauliniu lygmeniu. Šiandienos demokratijų kontekste būtų sunku įsivaizduoti visuomenę, neturinčią teisės kalbėti, laisvai ir nuo niekieno nepriklausomai reikšti savo mintis bei idėjas. Pats žodžio laisvės konceptas buvo socialiai konstruojamas dar nuo amžių prieš Kristų, kuomet žodžio laisvė buvo prilyginama vyrų teisei laisvai kalbėti politinėmis temomis. Atsiradus ir plėtojantis pi...

An index of beam hardening artifact for two-dimensional cone-beam CT tomographic images: establishment and preliminary evaluation

Science.gov (United States)

Yuan, Fusong; Lv, Peijun; Yang, Huifang; Wang, Yong; Sun, Yuchun

2015-07-01

Objectives: Based on the pixel gray value measurements, establish a beam-hardening artifacts index of the cone-beam CT tomographic image, and preliminarily evaluate its applicability. Methods: The 5mm-diameter metal ball and resin ball were fixed on the light-cured resin base plate respectively, while four vitro molars were fixed above and below the ball, on the left and right respectively, which have 10mm distance with the metal ball. Then, cone beam CT was used to scan the fixed base plate twice. The same layer tomographic images were selected from the two data and imported into the Photoshop software. The circle boundary was built through the determination of the center and radius of the circle, according to the artifact-free images section. Grayscale measurement tools were used to measure the internal boundary gray value G0, gray value G1 and G2 of 1mm and 20mm artifacts outside the circular boundary, the length L1 of the arc with artifacts in the circular boundary, the circumference L2. Hardening artifacts index was set A = (G1 / G0) * 0.5 + (G2 / G1) * 0.4 + (L2 / L1) * 0.1. Then, the A values of metal and resin materials were calculated respectively. Results: The A value of cobalt-chromium alloy material is 1, and resin material is 0. Conclusion: The A value reflects comprehensively the three factors of hardening artifacts influencing normal oral tissue image sharpness of cone beam CT. The three factors include relative gray value, the decay rate and range of artifacts.

Z-Index Parameterization for Volumetric CT Image Reconstruction via 3-D Dictionary Learning.

Science.gov (United States)

Bai, Ti; Yan, Hao; Jia, Xun; Jiang, Steve; Wang, Ge; Mou, Xuanqin

2017-12-01

Despite the rapid developments of X-ray cone-beam CT (CBCT), image noise still remains a major issue for the low dose CBCT. To suppress the noise effectively while retain the structures well for low dose CBCT image, in this paper, a sparse constraint based on the 3-D dictionary is incorporated into a regularized iterative reconstruction framework, defining the 3-D dictionary learning (3-DDL) method. In addition, by analyzing the sparsity level curve associated with different regularization parameters, a new adaptive parameter selection strategy is proposed to facilitate our 3-DDL method. To justify the proposed method, we first analyze the distributions of the representation coefficients associated with the 3-D dictionary and the conventional 2-D dictionary to compare their efficiencies in representing volumetric images. Then, multiple real data experiments are conducted for performance validation. Based on these results, we found: 1) the 3-D dictionary-based sparse coefficients have three orders narrower Laplacian distribution compared with the 2-D dictionary, suggesting the higher representation efficiencies of the 3-D dictionary; 2) the sparsity level curve demonstrates a clear Z-shape, and hence referred to as Z-curve, in this paper; 3) the parameter associated with the maximum curvature point of the Z-curve suggests a nice parameter choice, which could be adaptively located with the proposed Z-index parameterization (ZIP) method; 4) the proposed 3-DDL algorithm equipped with the ZIP method could deliver reconstructions with the lowest root mean squared errors and the highest structural similarity index compared with the competing methods; 5) similar noise performance as the regular dose FDK reconstruction regarding the standard deviation metric could be achieved with the proposed method using (1/2)/(1/4)/(1/8) dose level projections. The contrast-noise ratio is improved by ~2.5/3.5 times with respect to two different cases under the (1/8) dose level compared

Integrative image segmentation optimization and machine learning approach for high quality land-use and land-cover mapping using multisource remote sensing data

Science.gov (United States)

Gibril, Mohamed Barakat A.; Idrees, Mohammed Oludare; Yao, Kouame; Shafri, Helmi Zulhaidi Mohd

2018-01-01

The growing use of optimization for geographic object-based image analysis and the possibility to derive a wide range of information about the image in textual form makes machine learning (data mining) a versatile tool for information extraction from multiple data sources. This paper presents application of data mining for land-cover classification by fusing SPOT-6, RADARSAT-2, and derived dataset. First, the images and other derived indices (normalized difference vegetation index, normalized difference water index, and soil adjusted vegetation index) were combined and subjected to segmentation process with optimal segmentation parameters obtained using combination of spatial and Taguchi statistical optimization. The image objects, which carry all the attributes of the input datasets, were extracted and related to the target land-cover classes through data mining algorithms (decision tree) for classification. To evaluate the performance, the result was compared with two nonparametric classifiers: support vector machine (SVM) and random forest (RF). Furthermore, the decision tree classification result was evaluated against six unoptimized trials segmented using arbitrary parameter combinations. The result shows that the optimized process produces better land-use land-cover classification with overall classification accuracy of 91.79%, 87.25%, and 88.69% for SVM and RF, respectively, while the results of the six unoptimized classifications yield overall accuracy between 84.44% and 88.08%. Higher accuracy of the optimized data mining classification approach compared to the unoptimized results indicates that the optimization process has significant impact on the classification quality.

Synthesis and evaluation of 18f-labeled benzylideneaniline derivatives as new biomarkers for β-amyloid imaging in Alzheimer's disease

International Nuclear Information System (INIS)

B, Rai Ganeaha; Jeong, Jae Min; Lee, Yun Sang; Chang, Young Soo; Kim, Young Ju; Kim, Hyung Woo; Lee, Dong Soo; Chung, June Key; Lee, Myung Chul

2005-01-01

Noninvasive early detection of the Aβ plaques in Alzheimer's disease (AD) brain may be useful tool for the treatment of AD patients. We herein describe the synthesis of 18 F-labeled benzylideneaniline derivatives utilizing a novel labeling approach for imaging Aβ plaques in AD patients. Condensation of [ 18 F] 4-fluorobenzaldehyde with various aromatic amines afforded 18 F-labeled benzylideneaniline derivatives. The biodistribution of 18F-Iabeled benzylideneaniline derivatives was studied with ICR male mice. The binding affinities of the cold compounds to Aβ (1-40) were determined using [ 125 I] 2-(3'-iodo-4-methylaminophenyl) benzothiazole as a reference standard. The radiochemical yields were 32-44% and radiochemical purities were above 99% after purification. Log P values of the compounds were 1.56-1.58. Some of the benzylideneaniline derivatives showed relatively high binding affinity to Aβ (1-40) aggregates (Ki 149-304 nM). The 18 F-labeled benzylideneaniline derivatives displayed high brain uptake ratio in normal mice (2.9-24.93). The study suggests that these 18 F-labeled compounds may be suitable for Aβ plaque imaging in AD patients

Alelopatia de extratos voláteis na germinação de sementes e no comprimento da raiz de alface Allelopathy of plant volatile extracts on seed germination and radicle length of lettuce

Directory of Open Access Journals (Sweden)

Maria da Conceição Sampaio Alves

2004-11-01

Full Text Available O objetivo deste trabalho foi identificar possíveis efeitos alelopáticos de extratos voláteis de óleos essenciais na germinação e no comprimento da raiz de plântulas de alface. Foram utilizadas cinco concentrações de cada óleo (0,0, 0,001, 0,01, 0,1 e 1,0%, v/v, em delineamento inteiramente casualizado, com quatro repetições de 25 sementes de alface. Os extratos voláteis de óleos essenciais de canela, alecrim-pimenta, capim-citronela e alfavaca-cravo evidenciaram potencialidades alelopáticas na germinação e comprimento das raízes de plântulas de alface, efeitos que variaram de acordo com a concentração do óleo. O extrato volátil de óleo de jaborandi estimula o crescimento da radícula e não provoca inibição da germinação de sementes de alface, caracterizando-se como de efeito alelopático benéfico.The objective of this work was to identify allelopathic effects of volatile extracts of essential oils on germination and radicle length of lettuce seedlings. Five concentrations were utilized for each oil (0.0, 0.001, 0.01, 0.1 and 1.0%, v/v arranged into a completely randomized design with four replicates of 25 seeds. The volatile extracts of essential oils of cinnamon, alecrim-pimenta, capim-citronela and alfavaca-cravo revealed allelopathic potentialities on lettuce seed germination and radicle growth, effect which varied according to the oil concentration. The volatile extract of Jaborandi essential oil stimulates radicle growth and does not inhibit lettuce seeds germination, which is characterized as a beneficial allelopathic effect.

Glioma grade assessment by using histogram analysis of diffusion tensor imaging-derived maps

International Nuclear Information System (INIS)

Jakab, Andras; Berenyi, Ervin; Molnar, Peter; Emri, Miklos

2011-01-01

Current endeavors in neuro-oncology include morphological validation of imaging methods by histology, including molecular and immunohistochemical techniques. Diffusion tensor imaging (DTI) is an up-to-date methodology of intracranial diagnostics that has gained importance in studies of neoplasia. Our aim was to assess the feasibility of discriminant analysis applied to histograms of preoperative diffusion tensor imaging-derived images for the prediction of glioma grade validated by histomorphology. Tumors of 40 consecutive patients included 13 grade II astrocytomas, seven oligoastrocytomas, six grade II oligodendrogliomas, three grade III oligoastrocytomas, and 11 glioblastoma multiformes. Preoperative DTI data comprised: unweighted (B 0 ) images, fractional anisotropy, longitudinal and radial diffusivity maps, directionally averaged diffusion-weighted imaging, and trace images. Sampling consisted of generating histograms for gross tumor volumes; 25 histogram bins per scalar map were calculated. The histogram bins that allowed the most precise determination of low-grade (LG) or high-grade (HG) classification were selected by multivariate discriminant analysis. Accuracy of the model was defined by the success rate of the leave-one-out cross-validation. Statistical descriptors of voxel value distribution did not differ between LG and HG tumors and did not allow classification. The histogram model had 88.5% specificity and 85.7% sensitivity in the separation of LG and HG gliomas; specificity was improved when cases with oligodendroglial components were omitted. Constructing histograms of preoperative radiological images over the tumor volume allows representation of the grade and enables discrimination of LG and HG gliomas which has been confirmed by histopathology. (orig.)

Whether administration of justice is exceptionally only a human right?

OpenAIRE

Sapetkaitė, Gabrielė

2017-01-01

Šio darbo tikslas yra aptarti teisingumo vykdymą kaip tradicinę žmogaus teisę, dirbtinio intelekto sistemų poveikį teisės srityje bei pateikti galimus žmogaus teisės vykdyti teisingumą reguliavimo sprendimus dirbtinio intelekto sistemų kontekste. Darbo objektas yra – žmogaus teisė vykdyti teisingumą. Magistro darbu yra siekiama paanalizuoti mokslinę problemą ir atsakyti į klausimą ar teisingumo vykdymas yra išimtinai tik žmogaus teisė? Siekiant atsakyti į šį klausimą darbe yra pateikiami užsi...

Unification and approximation of the law of civil procedure

OpenAIRE

Juronytė, Austė

2014-01-01

Šiame darbe yra analizuojami bendrieji civilinio proceso teisės vienodinimo ir derinimo civilinėse ir komercinėse bylose teorinai ir praktiniai klausimai: tai civilinio proceso teisės samprata, istorija ir pagrindiniai šių dienų civilinio proceso teisės raidos bruožai. Taip pat pirmojoje darbo dalyje analizuojamos civilinio proceso teisės vienodinimo kliūtys bei pagrindinės civilinio proceso teisės vienodinimo priežastys arba tikslai, svarstoma kiek jos yra pagrįstos. Antroji darbo dalis yra ...

Cultural Resource Predictive Model Literature and Records Search for Conesus Lake N.Y.

Science.gov (United States)

1980-02-01

Science Service Memoir 20. Savavd, Peter G. 1968 Plant Production in Conesus Lake, New York, As A Guide to the Effects of Pollution in the Qrpat Tak...Turner,Jae1851 Hisory of the Pioneer Settlenent of Phelps and Gorham’s Purchase, and Morris’ Reserve, Vol. I. William Ailing, ZEc ..tei. 1973 index to the

Perceived Body Image, Eating Behavior, and Sedentary Activities and Body Mass Index Categories in Kuwaiti Female Adolescents

Directory of Open Access Journals (Sweden)

Lemia H. Shaban

2016-01-01

Full Text Available Background. The State of Kuwait has a growing obesity epidemic in both genders and all age groups; however, obesity rates in the young seem to be rising. Methods. We conducted a cross-sectional survey in 169 Kuwaiti female adolescents attending both private and public schools spanning the six governorates in the State of Kuwait in order to explore female adolescents’ self-image, body dissatisfaction, type of school (private versus public, TV viewing, and computer games and their relationship to body mass index. Results. Approximately half the students classified as obese perceived their body image to lie in the normal range. Females in the obese category were the most dissatisfied with their body image, followed by those in the overweight category. Eating behavior, level of physical activity, school type, television viewing, computer/video usage, and desired BMI were not significantly associated with level of obesity. Conclusion. This study was one of the few studies to assess adolescent females’ body image dissatisfaction in relation to obesity in the State of Kuwait. The results suggest that including body image dissatisfaction awareness into obesity prevention programs would be of value.

Fluorescent carbon nanoparticles derived from natural materials of mango fruit for bio-imaging probes

Science.gov (United States)

Jeong, Chan Jin; Roy, Arup Kumer; Kim, Sung Han; Lee, Jung-Eun; Jeong, Ji Hoon; Insik; Park, Sung Young

2014-11-01

Water soluble fluorescent carbon nanoparticles (FCP) obtained from a single natural source, mango fruit, were developed as unique materials for non-toxic bio-imaging with different colors and particle sizes. The prepared FCPs showed blue (FCP-B), green (FCP-G) and yellow (FCP-Y) fluorescence, derived by the controlled carbonization method. The FCPs demonstrated hydrodynamic diameters of 5-15 nm, holding great promise for clinical applications. The biocompatible FCPs demonstrated great potential in biological fields through the results of in vitro imaging and in vivo biodistribution. Using intravenously administered FCPs with different colored particles, we precisely defined the clearance and biodistribution, showing rapid and efficient urinary excretion for safe elimination from the body. These findings therefore suggest the promising possibility of using natural sources for producing fluorescent materials.Water soluble fluorescent carbon nanoparticles (FCP) obtained from a single natural source, mango fruit, were developed as unique materials for non-toxic bio-imaging with different colors and particle sizes. The prepared FCPs showed blue (FCP-B), green (FCP-G) and yellow (FCP-Y) fluorescence, derived by the controlled carbonization method. The FCPs demonstrated hydrodynamic diameters of 5-15 nm, holding great promise for clinical applications. The biocompatible FCPs demonstrated great potential in biological fields through the results of in vitro imaging and in vivo biodistribution. Using intravenously administered FCPs with different colored particles, we precisely defined the clearance and biodistribution, showing rapid and efficient urinary excretion for safe elimination from the body. These findings therefore suggest the promising possibility of using natural sources for producing fluorescent materials. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr04805a

Filters involving derivatives with application to reconstruction from scanned halftone images

DEFF Research Database (Denmark)

Forchhammer, Søren; Jensen, Kim S.

1995-01-01

This paper presents a method for designing finite impulse response (FIR) filters for samples of a 2-D signal, e.g., an image, and its gradient. The filters, which are called blended filters, are decomposable in three filters, each separable in 1-D filters on subsets of the data set. Optimality...... in the minimum mean square error sense (MMSE) of blended filtering is shown for signals with separable autocorrelation function. Relations between correlation functions for signals and their gradients are derived. Blended filters may be composed from FIR Wiener filters using these relations. Simple blended...... is achievable with blended filters...

Design and Fabrication of Large Diameter Gradient-Index Lenses for Dual-Band Visible to Short-Wave Infrared Imaging Applications

Science.gov (United States)

Visconti, Anthony Joseph

The fabrication of gradient-index (GRIN) optical elements is quite challenging, which has traditionally restricted their use in many imaging systems; consequently, commercial-level GRIN components usually exist in one particular market or niche application space. One such fabrication technique, ion exchange, is a well-known process used in the chemical strengthening of glass, the fabrication of waveguide devices, and the production of small diameter GRIN optical relay systems. However, the manufacturing of large diameter ion-exchanged GRIN elements has historically been limited by long diffusion times. For example, the diffusion time for a 20 mm diameter radial GRIN lens in commercially available ion exchange glass for small diameter relays, is on the order of a year. The diffusion time can be dramatically reduced by addressing three key ion exchange process parameters; the composition of the glass, the diffusion temperature, and the composition of the salt bath. Experimental work throughout this thesis aims to (1) scale up the ion exchange diffusion process to 20 mm diameters for a fast-diffusing titania silicate glass family in both (2) sodium ion for lithium ion (Na+ for Li+) and lithium ion for sodium ion (Li+ for Na+) exchange directions, while (3) utilizing manufacturing friendly salt bath compositions. In addition, optical design studies have demonstrated that an important benefit of gradient-index elements in imaging systems is the added degree of freedom introduced with a gradient's optical power. However, these studies have not investigated the potential usefulness of GRIN materials in dual-band visible to short-wave infrared (vis-SWIR) imaging systems. The unique chromatic properties of the titania silicate ion exchange glass become a significant degree of freedom in the design process for these color-limited, broadband imaging applications. A single GRIN element can replace a cemented doublet or even a cemented triplet, without loss in overall system

Three-dimensional image technology in forensic anthropology: Assessing the validity of biological profiles derived from CT-3D images of the skeleton

Science.gov (United States)

Garcia de Leon Valenzuela, Maria Julia

This project explores the reliability of building a biological profile for an unknown individual based on three-dimensional (3D) images of the individual's skeleton. 3D imaging technology has been widely researched for medical and engineering applications, and it is increasingly being used as a tool for anthropological inquiry. While the question of whether a biological profile can be derived from 3D images of a skeleton with the same accuracy as achieved when using dry bones has been explored, bigger sample sizes, a standardized scanning protocol and more interobserver error data are needed before 3D methods can become widely and confidently used in forensic anthropology. 3D images of Computed Tomography (CT) scans were obtained from 130 innominate bones from Boston University's skeletal collection (School of Medicine). For each bone, both 3D images and original bones were assessed using the Phenice and Suchey-Brooks methods. Statistical analysis was used to determine the agreement between 3D image assessment versus traditional assessment. A pool of six individuals with varying experience in the field of forensic anthropology scored a subsample (n = 20) to explore interobserver error. While a high agreement was found for age and sex estimation for specimens scored by the author, the interobserver study shows that observers found it difficult to apply standard methods to 3D images. Higher levels of experience did not result in higher agreement between observers, as would be expected. Thus, a need for training in 3D visualization before applying anthropological methods to 3D bones is suggested. Future research should explore interobserver error using a larger sample size in order to test the hypothesis that training in 3D visualization will result in a higher agreement between scores. The need for the development of a standard scanning protocol focusing on the optimization of 3D image resolution is highlighted. Applications for this research include the possibility

Three-dimensional speckle tracking imaging assessment of left ventricular change in patient with coronary heart disease and its correlation with serum indexes

Directory of Open Access Journals (Sweden)

Jian-Li Fu

2016-10-01

Full Text Available Objective: To analyze the three-dimensional speckle tracking imaging assessment of left ventricular change in patient with coronary heart disease and its correlation with serum indexes. Methods: A total of 152 patients first diagnosed with coronary heart disease were the observation group of the study and 117 healthy subjects were the control group. Threedimensional speckle tracking imaging (3D-STI was used to evaluate the left ventricular function parameters of two groups, the serum content of endothelial function indexes and platelet function indexes were detected, and the correlation between left ventricular function parameters under 3D-STI and serum indexes was further analyzed. Results: Absolute values of left ventricular function parameters LVGLS, LVGRS, LVGCS and LVGAS from 3D-STI of observation group were significantly less than those of control group while Ptw and Torsion levels were greater than those of control group; endothelial function indexes vWF, sICAM-1, sVCAM-1 and ET-1 content in serum were significantly higher than those of control group while vWF-cp and NO content were significantly lower than those of control group; platelet function indexes CD62P, GMP-140, CD63, sP-selectin, sCD40L and PAC-1 content in serum were significantly higher than those of control group. The levels of left ventricular function parameters from 3D-STI in patients with coronary heart disease were directly correlated with serum indexes. Conclusion: 3D-STI can accurately assess the left ventricular function and the overall disease severity in patients with coronary heart disease, and it is expected to become an effective method for early diagnosis of diseases and guidance of clinical treatment.

Browse Title Index

African Journals Online (AJOL)

Items 101 - 150 of 985 ... Journal Home > Advanced Search > Browse Title Index ... Vol 17 (2010), Alternating Direction Implicit Finite Difference Time Domain Acoustic Wave Algorithm, Abstract. E Ikata .... Vol 17 (2010), Analytic derivation of the wave profile and phase speed of sixth order Stokes waves in deep water, Abstract.

Prediction Center (CPC) Polar Eurasia Teleconnection Pattern Index

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Monthly tabulated index of the Polar-Eurasia teleconnection pattern. The data spans the period 1950 to present. The index is derived from a rotated principal...

Climate Prediction Center (CPC) Scandinavia Teleconnection Pattern Index

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Monthly tabulated index of the Scandinavia teleconnection pattern. The data spans the period 1950 to present. The index is derived from a rotated principal component...

Identificação de compostos voláteis da cúrcuma empregando microextração por fase sólida e cromatografia gasosa acoplada à espectrometria de massas Identification of volatile compounds of turmeric using solid phase microextraction and gas chromatography coupled to mass spectrometry

Directory of Open Access Journals (Sweden)

Adriana R. Mata

2004-03-01

Full Text Available Compostos voláteis da cúrcuma (Curcuma longa L. cultivada no Brasil foram isolados por microextração por fase sólida. Os rizomas foram cozidos em solução de bicarbonato de sódio 0,1%, fatiados, secos e triturados. Visando estabelecer o sistema ideal para a microextração, fibras de polidimetilsiloxano de 100µm de espessura foram expostas ao headspace de frascos de 10mL. Estudou-se a influência das seguintes variáveis sobre o rendimento dos compostos voláteis obtidos: amostras em pó (0,1 a 1,0g e em solução (40mg/L, diferentes temperaturas (40 a 70ºC e tempos (2 a 20min de partição. O efeito da temperatura (210 a 240ºC e do tempo (3 e 5min de dessorção também foi avaliado. As melhores condições para a partição dos compostos voláteis foram 0,1g do pó, 70ºC e 5min. A temperatura de 220ºC e o tempo de 5 minutos foram os de maior eficiência para a dessorção. A cromatografia gasosa foi conduzida em coluna capilar, detecção por ionização de chama e identificação por espectrometria de massas. A análise dos espectros de massas obtidos para os nove compostos voláteis predominantes indicou a presença de ar-curcúmeno, ar-turmerona, zingibereno, beta-sesquifelandreno, sabineno, 1,8-cineol e 1,4-terpineol.Volatile compounds from turmeric (Curcuma longa L. cultived in Brazil were isolated by solid phase microextraction. The rhizomes were cooked in 0.1% sodium bicarbonate solution, sliced, dried and ground. Polydimethyldiloxanes fibers (100 mm diameter were exposed to the headspace of 10 mL flasks with the aim of establishing an ideal microextraction system. The influence of the following parameters on the volatile substances obtained was studied: powder samples (0.1 to 1.0 g and dissolved samples (40 mg/L, different temperatures (40 to 70ºC and partition periods (2 to 20 min. The effect of temperature (210 to 240ºC and time (3 to 5 min on desorption efficiency was also evaluated. Optimum conditions for the

Clearing and settlement of exchange traded derivatives

OpenAIRE

John McPartland

2009-01-01

Derivatives are a class of financial instruments that derive their value from some underlying commodity, security, index, or other asset. Futures and options are common forms of derivatives. This article explains how clearing and settlement systems for exchange traded derivatives work.

RadLex - German version: a radiological lexicon for indexing image and report information

International Nuclear Information System (INIS)

Marwede, D.; Lobsien, D.; Kahn, T.; Daumke, P.; Marko, K.; Schulz, S.

2009-01-01

Purpose: Since 2003 the Radiological Society of North America (RSNA) has been developing a lexicon of standardized radiological terms (RadLex) intended to support the structured reporting of imaging observations and the indexing of teaching cases. The aim of this study was to translate the first version of the lexicon (1 - 2007) into German and to implement a language-independent online term browser. Materials and Methods: RadLex version 1 - 2007 contains 6303 terms in nine main categories. Two radiologists independently translated the lexicon using medical dictionaries. Terms translated differently were revised and translated by consensus. For the development of an online term browser, a text processing algorithm called morphosemantic indexing was used which splits up words into small semantic units and compares those units to language-specific subword thesauri. Results: In total 6240 of 6303 terms (99 %) were translated. Of those terms 3965 were German, 1893 were Latin, 359 were multilingual, and 23 were English terms that are also used in German and were therefore maintained. The online term browser supports a language-independent term search in RadLex (German/English) and other common medical terminology (e.g., ICD 10). The term browser displays term hierarchies and translations in different frames and the complexity of the result lists can be adapted by the user. Conclusion: RadLex version 1 - 2007 developed by the RSNA is now available in German and can be accessed online through a term browser with an efficient search function. This is an important precondition for the future comparison of national and international indexed radiological examination results and the interoperability between digital teaching resources. (orig.)

Application of DOI index to analysis of selected examples of resistivity imaging models in Quaternary sediments

Directory of Open Access Journals (Sweden)

Glazer Michał

2014-12-01

Full Text Available Interpretation of resistivity cross sections may be in many cases unreliable due to the presence of artifacts left by the inversion process. One way to avoid erroneous conclusions about geological structure is creation of Depth of Investigation (DOI index maps, which describe durability of prepared model with respect to variable parameters of inversion. To assess the usefulness of this interpretation methodology in resistivity imaging method over quaternary sediments, it has been used to one synthetic data set and three investigation sites. Two of the study areas were placed in the Upper Silesian Industrial District region: Bytom - Karb, Chorzów - Chorzow Stary; and one in the Southern Pomeranian Lake District across Piława River Valley. Basing on the available geological information the results show high utility of DOI index in analysis of received resistivity models, on which areas poorly constrained by data has been designated.

A Three-Dimensional Index for Characterizing Crop Water Stress

Directory of Open Access Journals (Sweden)

Jessica A. Torrion

2014-05-01

Full Text Available The application of remotely sensed estimates of canopy minus air temperature (Tc-Ta for detecting crop water stress can be limited in semi-arid regions, because of the lack of full ground cover (GC at water-critical crop stages. Thus, soil background may restrict water stress interpretation by thermal remote sensing. For partial GC, the combination of plant canopy temperature and surrounding soil temperature in an image pixel is expressed as surface temperature (Ts. Soil brightness (SB for an image scene varies with surface soil moisture. This study evaluates SB, GC and Ts-Ta and determines a fusion approach to assess crop water stress. The study was conducted (2007 and 2008 on a commercial scale, center pivot irrigated research site in the Texas High Plains. High-resolution aircraft-based imagery (red, near-infrared and thermal was acquired on clear days. The GC and SB were derived using the Perpendicular Vegetation Index approach. The Ts-Ta was derived using an array of ground Ts sensors, thermal imagery and weather station air temperature. The Ts-Ta, GC and SB were fused using the hue, saturation, intensity method, respectively. Results showed that this method can be used to assess water stress in reference to the differential irrigation plots and corresponding yield without the use of additional energy balance calculation for water stress in partial GC conditions.

Development of a mobile multispectral imaging platform for precise field phenotyping

DEFF Research Database (Denmark)

Svensgaard, Jesper; Roitsch, Thomas Georg; Christensen, Svend

2014-01-01

nitrogen levels, replicated on two different soil types at four different dates from 15 May (BBCH 13) to 18 June (BBCH 41 to 57). The images were analyzed and derived vegetation coverage and Normalized Difference Vegetation index (NDVI) were used to assess varietal differences. The results showed...... potentials for differentiating between the varieties using both vegetation coverage and NDVI, especially at the early growth stages. The perspectives of high-precision and high-throughput imaging for field phenotyping are discussed including the potentials of measuring varietal differences via spectral...

Sex and Age Differences in Body-Image, Self-Esteem, and Body Mass Index in Adolescents and Adults After Single-Ventricle Palliation

OpenAIRE

Pike, Nancy A.; Evangelista, Lorraine S.; Doering, Lynn V.; Eastwood, Jo-Ann; Lewis, Alan B.; Child, John S.

2012-01-01

Single-ventricle congenital heart disease (SVCHD) requires multiple palliative surgical procedures that leave visible surgical scars and physical deficits, which can alter body-image and self-esteem. This study aimed to compare sex and age differences in body-image, selfesteem, and body mass index (BMI) in adolescents and adults with SVCHD after surgical palliation with those of a healthy control group. Using a comparative, cross-sectional design, 54 adolescent and adult (26 male and 28 femal...

Analysis of glucose metabolism in patients with diabetes mellitus by using functional images derived from 18F-FDG PET

International Nuclear Information System (INIS)

Ohtake, Tohru; Yokoyama, Ikuo; Watanabe, Toshiaki; Kosaka, Noboru; Momose, Toshimitsu; Nishikawa, Jun-ichi; Serizawa, Takashi; Sasaki, Yasuhito

1993-01-01

Functional images of K complex (KC) and regional myocardial glucose utilization rates (rMGU), derived from F-18-fluoro-deoxy-glucose (F-18-FDG) positron emission computed tomography, were prepared. Using functional images obtained, myocardial glucose metabolism was examined in the fasting state, oral glucose loading (OG), and insulin clamp (IC) condition. The subjects were 10 patients with diabetes mellitus (DM), consisting of 8 with non-insulin dependent DM and 2 with insulin dependent DM, and 4 normal persons. Image quality, derived from both OG and IC approaches, was favorable in the normal group. In the groups of non-insulin dependent DM and insulin dependent DM patients, however, image quality was good with IC method but not with OG method. In the group of non-insulin dependent DM, rMGU derived by IC method was relatively high, but was significantly lower than that in the control group, suggesting a decreased function in glucose transporter. When using OG method, rMGU was even more decreased due to high blood sugar and low insulin. In the group of insulin dependent DM, both IC and OG approaches achieved the same rMGU as that in the control group, with the exception of KC derived by OG method that was decreased due to high blood sugar. In moderate or severe DM, myocardial viability seems to be difficult to evaluate because F-18-FDG uptake is decreased in the ischemic area associated with fasting high blood sugar. Mismatching between blood flow and metabolism is also difficult to detect due to high insulin or glucose load. Thus, myocardial viability should be evaluated in the condition of slightly loaded insulin by decreasing blood sugar. (N.K.)

A new relative hazard index

International Nuclear Information System (INIS)

Smith, C.F.; Burnett, T.W.T; Kastenberg, W.E.

1976-01-01

Several indexes for the evaluation of relative radionuclide hazards have been previously developed. In this paper, a new relative hazard index is derived for use in the assessment of the future burden to mankind from the presence of radionuclides in the environment. Important features of this hazard index are that it takes into account multiple decay schemes, non-equilibrium conditions, and finite time periods. As an application of this hazard index, a comparison is made between thermal reactor radioactive waste and the uranium required as fuel with the following conclusions: (1) For short time intervals (d 234 U breaking the uranium decay chain. (3) For long time intervals of concern (d >= 500 000 years), the reactor waste and consumed uranium indexes are equal after a much shorter decay time (approximately 10 years.) (author)

On the Economic Consequences of Index-Linked Investing

OpenAIRE

Jeffrey Wurgler

2010-01-01

Trillions of dollars are invested through index funds, exchange-traded funds, and other index derivatives. The benefits of index-linked investing are well-known, but the possible broader economic consequences are unstudied. I review research which suggests that index-linked investing is distorting stock prices and risk-return tradeoffs, which in turn may be distorting corporate investment and financing decisions, investor portfolio allocation decisions, fund manager skill assessments, and oth...

Synthesis of 18F labeled clotrimazole derivatives as a potential PET imaging agent

International Nuclear Information System (INIS)

Jung, Soon Jae; Kim, In Jong; Park, Jeong Hoon; Lee, Heung Nae; Kim, Sang Wook; Hur, Min Goo; Choi, Sang Moo; Yang, Seung Dae; Yu, Kook Hyun

2010-01-01

Clotrimazole [1- -1H-imidazole, CLT] has been reported to inhibit the proliferation of vascular endothelial and act as an in vitro anti-VEGF drug. It is also shown to inhibit angiogenesis in an animal model. The radioisotope labeled clotrimazole derivative can be utilized to monitor the physiologic processes of cancer. In this study, we synthesized [ 18 F]fluoride labeled clotrimazole derivatives as a new tumor imaging agent for PET. The references were prepared by a refluxing with clotrimazole and an excess of fluoroalkyltosylate in acetonitrile for 36 h and clotrimazole reacted with ditosylalkane to give precursors. [ 18 ]Fluoride labeled reaction was performed with precursor in Kryptofix[2.2.2]/K 2 CO 3 for 10 min at 80 .deg. C. The radiolabeling mixture was passed through a silica Sep-Pak cartridge to remove 18 F - . The [ 18 ]F-clotrimazole derivatives were synthesized with a 20 ∼ 25% yield. In the radiofluoriantion step, we used acetonitrile and DMSO as a solvent and observed a higher at the acetonitrile (25%) reaction compared with the DMSO reaction (5%)

Left ventricular fluid dynamics in heart failure: echocardiographic measurement and utilities of vortex formation time.

Science.gov (United States)

Poh, Kian Keong; Lee, Li Ching; Shen, Liang; Chong, Eric; Tan, Yee Leng; Chai, Ping; Yeo, Tiong Cheng; Wood, Malissa J

2012-05-01

In clinical heart failure (HF), inefficient propagation of blood through the left ventricle (LV) may result from suboptimal vortex formation (VF) ability of the LV during early diastole. We aim to (i) validate echocardiographic-derived vortex formation time (adapted) (VFTa) in control subjects and (ii) examine its utility in both systolic and diastolic HF. Transthoracic echocardiography was performed in 32 normal subjects and in 130 patients who were hospitalized with HF [91, reduced ejection fraction (rEF) and 39, preserved ejection fraction (pEF)]. In addition to biplane left ventricular ejection fraction (LVEF) and conventional parameters, the Tei index and tissue Doppler (TD) indices were measured. VFTa was obtained using the formula: 4 × (1 - β)/π × α³ × LVEF, where β is the fraction of total transmitral diastolic stroke volume contributed by atrial contraction (assessed by time velocity integral of the mitral E- and A-waves) and α is the biplane end-diastolic volume (EDV)(1/3) divided by mitral annular diameter during early diastole. VFTa was correlated with demographic, cardiac parameters, and a composite clinical endpoint comprising cardiac death and repeat hospitalization for HF. Mean VFTa was 2.67 ± 0.8 in control subjects; reduced in HF, preserved EF HF, 2.21 ± 0.8; HF with reduced EF, 1.25 ± 0.6 (PTD early diastolic myocardial velocities (E', septal, r = 0.46; lateral, r = 0.43), systolic myocardial velocities (S', septal, r = 0.47; lateral, r = 0.41), and inversely with the Tei index (r = -0.41); all Ps < 0.001. Sixty-two HF patients (49%) met the composite endpoint. VFTa of <1.32 was associated with significantly reduced event-free survival (Kaplan Meier log rank = 16.3, P= 0.0001) and predicted the endpoint with a sensitivity and specificity of 65 and 72%, respectively. VFTa, a dimensionless index, incorporating LV geometry, systolic and diastolic parameters, may be useful in the diagnosis and prognosis of HF.

Whole-tumor MRI histogram analyses of hepatocellular carcinoma: Correlations with Ki-67 labeling index.

Science.gov (United States)

Hu, Xin-Xing; Yang, Zhao-Xia; Liang, He-Yue; Ding, Ying; Grimm, Robert; Fu, Cai-Xia; Liu, Hui; Yan, Xu; Ji, Yuan; Zeng, Meng-Su; Rao, Sheng-Xiang

2017-08-01

To evaluate whether whole-tumor histogram-derived parameters for an apparent diffusion coefficient (ADC) map and contrast-enhanced magnetic resonance imaging (MRI) could aid in assessing Ki-67 labeling index (LI) of hepatocellular carcinoma (HCC). In all, 57 patients with HCC who underwent pretreatment MRI with a 3T MR scanner were included retrospectively. Histogram parameters including mean, median, standard deviation, skewness, kurtosis, and percentiles (5 th , 25 th , 75 th , 95 th ) were derived from the ADC map and MR enhancement. Correlations between histogram parameters and Ki-67 LI were evaluated and differences between low Ki-67 (≤10%) and high Ki-67 (>10%) groups were assessed. Mean, median, 5 th , 25 th , 75 th percentiles of ADC, and mean, median, 25 th , 75 th , 95 th percentiles of enhancement of arterial phase (AP) demonstrated significant inverse correlations with Ki-67 LI (rho up to -0.48 for ADC, -0.43 for AP) and showed significant differences between low and high Ki-67 groups (P Histogram-derived parameters of ADC and AP were potentially helpful for predicting Ki-67 LI of HCC. 3 Technical Efficacy: Stage 3 J. MAGN. RESON. IMAGING 2017;46:383-392. © 2016 International Society for Magnetic Resonance in Medicine.

The precision of the NDVI derived from AVHRR observations

International Nuclear Information System (INIS)

Roderick, M.; Smith, R.; Cridland, S.

1996-01-01

Vegetation studies using NOAA-AVHRR data have tended to focus on the use of the normalized difference vegetation index (NDVI). This unitless index is computed using near-infrared and red reflectances, and thus has both an accuracy and precision. This article reports on a formal statistical framework for assessing the precision of the NDVI derived from NOAA-AVHRR observations. The framework is based on the “best possible” precision concept, which assumes that signal quantization is the only source of observational error. While the radiance resolution of a spectral observation is essentially fixed by the instrument characteristics, the reflectance resolution is the radiance resolution divided by the cosine of the solar zenith angle. Using typical solar zenith angles for AVHRR image acquisitions over Australia, ± 0.01 NDVI units is typically with “best possible” precision attainable in the NDVI, although this degrades significantly over dark targets, and at large solar zenith angles. Transforming the computed NDVI into a single byte for disk storage results in little or no loss of precision. The framework developed in this article can be adapted to estimate the “best possible” precision of other vegetation indices derived using data from other remote sensing satellites. (author)

Refractive Index Sensing of Green Fluorescent Proteins in Living Cells Using Fluorescence Lifetime Imaging Microscopy

Science.gov (United States)

van Manen, Henk-Jan; Verkuijlen, Paul; Wittendorp, Paul; Subramaniam, Vinod; van den Berg, Timo K.; Roos, Dirk; Otto, Cees

2008-01-01

We show that fluorescence lifetime imaging microscopy (FLIM) of green fluorescent protein (GFP) molecules in cells can be used to report on the local refractive index of intracellular GFP. We expressed GFP fusion constructs of Rac2 and gp91phox, which are both subunits of the phagocyte NADPH oxidase enzyme, in human myeloid PLB-985 cells and showed by high-resolution confocal fluorescence microscopy that GFP-Rac2 and GFP-gp91phox are targeted to the cytosol and to membranes, respectively. Frequency-domain FLIM experiments on these PLB-985 cells resulted in average fluorescence lifetimes of 2.70 ns for cytosolic GFP-Rac2 and 2.31 ns for membrane-bound GFP-gp91phox. By comparing these lifetimes with a calibration curve obtained by measuring GFP lifetimes in PBS/glycerol mixtures of known refractive index, we found that the local refractive indices of cytosolic GFP-Rac2 and membrane-targeted GFP-gp91phox are ∼1.38 and ∼1.46, respectively, which is in good correspondence with reported values for the cytosol and plasma membrane measured by other techniques. The ability to measure the local refractive index of proteins in living cells by FLIM may be important in revealing intracellular spatial heterogeneities within organelles such as the plasma and phagosomal membrane. PMID:18223002

Community detection for fluorescent lifetime microscopy image segmentation

Science.gov (United States)

Hu, Dandan; Sarder, Pinaki; Ronhovde, Peter; Achilefu, Samuel; Nussinov, Zohar

2014-03-01

Multiresolution community detection (CD) method has been suggested in a recent work as an efficient method for performing unsupervised segmentation of fluorescence lifetime (FLT) images of live cell images containing fluorescent molecular probes.1 In the current paper, we further explore this method in FLT images of ex vivo tissue slices. The image processing problem is framed as identifying clusters with respective average FLTs against a background or "solvent" in FLT imaging microscopy (FLIM) images derived using NIR fluorescent dyes. We have identified significant multiresolution structures using replica correlations in these images, where such correlations are manifested by information theoretic overlaps of the independent solutions ("replicas") attained using the multiresolution CD method from different starting points. In this paper, our method is found to be more efficient than a current state-of-the-art image segmentation method based on mixture of Gaussian distributions. It offers more than 1:25 times diversity based on Shannon index than the latter method, in selecting clusters with distinct average FLTs in NIR FLIM images.

Deriving a blood-mimicking fluid for particle image velocimetry in Sylgard-184 vascular models.

Science.gov (United States)

Yousif, Majid Y; Holdsworth, David W; Poepping, Tamie L

2009-01-01

A new blood-mimicking fluid (BMF) has been developed for particle image velocimetry (PIV), which enables flow studies in vascular models (phantoms). A major difficulty in PIV that affects measurement accuracy is the refraction and distortion of light passing through the interface between the model and the fluid, due to the difference in refractive index (n) between the two materials. The problem can be eliminated by using a fluid with a refractive index matching that of the model. Such fluids are not commonly available, especially for vascular research where the fluid should also have a viscosity similar to human blood. In this work, a blood-mimicking fluid, composed of water (47.38% by weight), glycerol (36.94% by weight) and sodium iodide salt (15.68% by weight), was developed for compatibility with our silicone (Sylgard 184; n = 1.414) phantoms. The fluid exhibits a dynamic viscosity of 4.31+/-0.03 cP which lies within the range of human blood viscosity (4.4+/-0.6 cP). Both refractive index and viscosity were attained at 22.2+/-0.2 degrees C, which is a feasible room temperature, thus eliminating the need for a temperature-control system. The fluid will be used to study hemodynamics in vascular flow models fabricated from Sylgard 184.

Forest fire danger index based on modifying Nesterov Index, fuel, and anthropogenic activities using MODIS TERRA, AQUA and TRMM satellite datasets

Science.gov (United States)

Suresh Babu, K. V.; Roy, Arijit; Ramachandra Prasad, P.

2016-05-01

Forest fire has been regarded as one of the major causes of degradation of Himalayan forests in Uttarakhand. Forest fires occur annually in more than 50% of forests in Uttarakhand state, mostly due to anthropogenic activities and spreads due to moisture conditions and type of forest fuels. Empirical drought indices such as Keetch-Byram drought index, the Nesterov index, Modified Nesterov index, the Zhdanko index which belongs to the cumulative type and the Angstrom Index which belongs to the daily type have been used throughout the world to assess the potential fire danger. In this study, the forest fire danger index has been developed from slightly modified Nesterov index, fuel and anthropogenic activities. Datasets such as MODIS TERRA Land Surface Temperature and emissivity (MOD11A1), MODIS AQUA Atmospheric profile product (MYD07) have been used to determine the dew point temperature and land surface temperature. Precipitation coefficient has been computed from Tropical Rainfall measuring Mission (TRMM) product (3B42RT). Nesterov index has been slightly modified according to the Indian context and computed using land surface temperature, dew point temperature and precipitation coefficient. Fuel type danger index has been derived from forest type map of ISRO based on historical fire location information and disturbance danger index has been derived from disturbance map of ISRO. Finally, forest fire danger index has been developed from the above mentioned indices and MODIS Thermal anomaly product (MOD14) has been used for validating the forest fire danger index.

Deriving a Mutation Index of Carcinogenicity Using Protein Structure and Protein Interfaces

Science.gov (United States)

Hakas, Jarle; Pearl, Frances; Zvelebil, Marketa

2014-01-01

With the advent of Next Generation Sequencing the identification of mutations in the genomes of healthy and diseased tissues has become commonplace. While much progress has been made to elucidate the aetiology of disease processes in cancer, the contributions to disease that many individual mutations make remain to be characterised and their downstream consequences on cancer phenotypes remain to be understood. Missense mutations commonly occur in cancers and their consequences remain challenging to predict. However, this knowledge is becoming more vital, for both assessing disease progression and for stratifying drug treatment regimes. Coupled with structural data, comprehensive genomic databases of mutations such as the 1000 Genomes project and COSMIC give an opportunity to investigate general principles of how cancer mutations disrupt proteins and their interactions at the molecular and network level. We describe a comprehensive comparison of cancer and neutral missense mutations; by combining features derived from structural and interface properties we have developed a carcinogenicity predictor, InCa (Index of Carcinogenicity). Upon comparison with other methods, we observe that InCa can predict mutations that might not be detected by other methods. We also discuss general limitations shared by all predictors that attempt to predict driver mutations and discuss how this could impact high-throughput predictions. A web interface to a server implementation is publicly available at http://inca.icr.ac.uk/. PMID:24454733

Object-based Morphological Building Index for Building Extraction from High Resolution Remote Sensing Imagery

Directory of Open Access Journals (Sweden)

LIN Xiangguo

2017-06-01

Full Text Available Building extraction from high resolution remote sensing images is a hot research topic in the field of photogrammetry and remote sensing. In this article, an object-based morphological building index (OBMBI is constructed based on both image segmentation and graph-based top-hat reconstruction, and OBMBI is used for building extraction from high resolution remote sensing images. First, bidirectional mapping relationship between pixels, objects and graph-nodes are constructed. Second, the OBMBI image is built based on both graph-based top-hat reconstruction and the above mapping relationship. Third, a binary thresholding is performed on the OBMBI image, and the binary image is converted into vector format to derive the building polygons. Finally, the post-processing is made to optimize the extracted building polygons. Two images, including an aerial image and a panchromatic satellite image, are used to test both the proposed method and classic PanTex method. The experimental results suggest that our proposed method has a higher accuracy in building extraction than the classic PanTex method. On average, the correctness, the completeness and the quality of our method are respectively 9.49%, 11.26% and 14.11% better than those of the PanTex.

Polarization-based index of refraction and reflection angle estimation for remote sensing applications

Science.gov (United States)

Thilak, Vimal; Voelz, David G.; Creusere, Charles D.

2007-10-01

A passive-polarization-based imaging system records the polarization state of light reflected by objects that are illuminated with an unpolarized and generally uncontrolled source. Such systems can be useful in many remote sensing applications including target detection, object segmentation, and material classification. We present a method to jointly estimate the complex index of refraction and the reflection angle (reflected zenith angle) of a target from multiple measurements collected by a passive polarimeter. An expression for the degree of polarization is derived from the microfacet polarimetric bidirectional reflectance model for the case of scattering in the plane of incidence. Using this expression, we develop a nonlinear least-squares estimation algorithm for extracting an apparent index of refraction and the reflection angle from a set of polarization measurements collected from multiple source positions. Computer simulation results show that the estimation accuracy generally improves with an increasing number of source position measurements. Laboratory results indicate that the proposed method is effective for recovering the reflection angle and that the estimated index of refraction provides a feature vector that is robust to the reflection angle.

Context indexing of digital cardiac ultrasound records in PACS

Science.gov (United States)

Lobodzinski, S. Suave; Meszaros, Georg N.

1998-07-01

Recent wide adoption of the DICOM 3.0 standard by ultrasound equipment vendors created a need for practical clinical implementations of cardiac imaging study visualization, management and archiving, DICOM 3.0 defines only a logical and physical format for exchanging image data (still images, video, patient and study demographics). All DICOM compliant imaging studies must presently be archived on a 650 Mb recordable compact disk. This is a severe limitation for ultrasound applications where studies of 3 to 10 minutes long are a common practice. In addition, DICOM digital echocardiography objects require physiological signal indexing, content segmentation and characterization. Since DICOM 3.0 is an interchange standard only, it does not define how to database composite video objects. The goal of this research was therefore to address the issues of efficient storage, retrieval and management of DICOM compliant cardiac video studies in a distributed PACS environment. Our Web based implementation has the advantage of accommodating both DICOM defined entity-relation modules (equipment data, patient data, video format, etc.) in standard relational database tables and digital indexed video with its attributes in an object relational database. Object relational data model facilitates content indexing of full motion cardiac imaging studies through bi-directional hyperlink generation that tie searchable video attributes and related objects to individual video frames in the temporal domain. Benefits realized from use of bi-directionally hyperlinked data models in an object relational database include: (1) real time video indexing during image acquisition, (2) random access and frame accurate instant playback of previously recorded full motion imaging data, and (3) time savings from faster and more accurate access to data through multiple navigation mechanisms such as multidimensional queries on an index, queries on a hyperlink attribute, free search and browsing.

A simple model for yield prediction of rice based on vegetation index derived from satellite and AMeDAS data during ripening period

International Nuclear Information System (INIS)

Wakiyama, Y.; Inoue, K.; Nakazono, K.

2003-01-01

The present study was conducted to show a simple model for rice yield predicting by using a vegetation index (NDVI) derived from satellite and meteorological data. In a field experiment, the relationship between the vegetation index and radiation absorbed by the rice canopy was investigated from transplanting to maturity. Their correlation held. This result revealed that the vegetation index could be used as a measure of absorptance of solar radiation by rice canopy. NDVI multiplied by solar radiation (SR) every day was accumulated (Σ(SR·NDVI)) from the field experiment. Σ(SR·NDVI) was plotted against above ground dry matter. It was obvious that they had a strong relationship. Rice yield largely depends on solar radiation and air temperature during the ripening period. Air temperature affects dry matter production. Relationships between Y SR -1 (Y: rice yield, SR: solar radiation) and mean air temperature were investigated from meteorological data and statistical data on rice yield. There was an optimum air temperature, 21.3°C, for ripening. When it was near 21.3°C in the ripening period, the rice yield was higher. We proposed a simple model for yield prediction of rice based on these results. The model is composed with SR·NDVI and the optimum air temperature. Vegetation index was derived from 3 years, LANDSAT TM data in Toyama, Ishikawa, Fukui and Nagano prefectures at heading. The meteorological data was used from AMeDAS data. The model was described as follows: Y = 0.728 SR·NDVI−2.04(T−21.3) 2 + 282 (r 2 = 0.65, n = 43) where Y is rice yield (kg 10a -1 ), SR is solar radiation (MJ m -2 ) during the ripening period (from 10 days before heading to 30 days after heading), T is mean air temperature (°C) during the ripening period. RMSE was 33.7kg 10a -1 . The model revealed good precision. (author)

Snacking Patterns in Children: A Comparison between Australia, China, Mexico, and the US.

Science.gov (United States)

Wang, Dantong; van der Horst, Klazine; Jacquier, Emma F; Afeiche, Myriam C; Eldridge, Alison L

2018-02-11

Snacking is common in children and influenced by many factors. The aim of this study is to provide insight of both common and country-specific characteristics of snacking among 4-13 year old children. We analyzed snacking prevalence, energy and nutrient contributions from snacking across diverse cultures and regions, represented by Australia, China, Mexico, and the US using data from respective national surveys. We found that the highest prevalence of snacking was in Australia and the US (over 95%) where snacking provided one-third and one-quarter of total energy intake (TEI), respectively, followed by Mexico (76%, provided 15% TEI) and China (65%, provided 10% TEI). Compared to 4-8 year-olds, the consumption of fruits and milk was lower in 9-13 year-old children, with a trend of increasing savory snacks consumption in China, Mexico, and the US. The nutrient density index of added sugars and saturated fat was higher, especially in Australia, Mexico, and the US. Results suggested that snacking could be an occasion to promote fruit and vegetable consumption in all countries, especially for older children. Snacking guidelines should focus on reducing consumption of snacks high in saturated fat and added sugars for Australia, Mexico, and the US, whereas improving dairy consumption is important in China.

Dynamic renal transplant imaging with /sup 99m/Tc DTPA (Sn) supplemented by a transplant perfusion index in the management of renal transplants

International Nuclear Information System (INIS)

Hilson, A.J.W.; Maisey, M.N.; Brown, C.B.; Ogg, C.S.; Bewick, M.S.

1978-01-01

We have performed 955 studies on 152 patients with 167 renal transplants. Images were recorded following bolus injection of 12 to 15 mCi Tc-99m DTPA (Sn). The data were stored on a computer and analyzed by generation of region-of-interest curves from (a) the iliac artery distal to the transplant, (b) the kidney, and (c) a background area. A perfusion index was adopted: arterial counts per cell, integrated to peak/concurrent renal counts per cell x 100. In 276 studies the patient clearly had acute tubular necrosis (ATN), rejection, or a normal kidney on retrospective analysis. The normal perfusion index has a value below 150, and it increases with falling perfusion, such as is seen in rejection and in renal-artery stenosis. The use of this index in addition to sequential images and changes in the region-of-interest curves usually allows separation of rejection from ATN and, particularly, rejection from normals. When serial studies are performed, the separation of rejecting from nonrejecting transplants is excellent, although renal-artery stenosis may cause similar changes in perfusion

High molecular weight chitosan derivative polymeric micelles encapsulating superparamagnetic iron oxide for tumor-targeted magnetic resonance imaging

Directory of Open Access Journals (Sweden)

Xiao Y

2015-02-01

Full Text Available Yunbin Xiao,1,* Zuan Tao Lin,2,* Yanmei Chen,1 He Wang,1 Ya Li Deng,2 D Elizabeth Le,3 Jianguo Bin,1 Meiyu Li,1 Yulin Liao,1 Yili Liu,1 Gangbiao Jiang,2 Jianping Bin1 1State Key Laboratory of Organ Failure Research, Division of Cardiology, Nanfang Hospital, Southern Medical University, Guangzhou, People’s Republic of China; 2Department of Pharmaceutical Engineering, South China Agricultural University, Guangzhou, People’s Republic of China; 3Cardiovascular Division, Oregon Health and Science University, Portland, OR, USA *These authors contributed equally to this work Abstract: Magnetic resonance imaging (MRI contrast agents based on chitosan derivatives have great potential for diagnosing diseases. However, stable tumor-targeted MRI contrast agents using micelles prepared from high molecular weight chitosan derivatives are seldom reported. In this study, we developed a novel tumor-targeted MRI vehicle via superparamagnetic iron oxide nanoparticles (SPIONs encapsulated in self-aggregating polymeric folate-conjugated N-palmitoyl chitosan (FAPLCS micelles. The tumor-targeting ability of FAPLCS/SPIONs was demonstrated in vitro and in vivo. The results of dynamic light scattering experiments showed that the micelles had a relatively narrow size distribution (136.60±3.90 nm and excellent stability. FAPLCS/SPIONs showed low cytotoxicity and excellent biocompatibility in cellular toxicity tests. Both in vitro and in vivo studies demonstrated that FAPLCS/SPIONs bound specifically to folate receptor-positive HeLa cells, and that FAPLCS/SPIONs accumulated predominantly in established HeLa-derived tumors in mice. The signal intensities of T2-weighted images in established HeLa-derived tumors were reduced dramatically after intravenous micelle administration. Our study indicates that FAPLCS/SPION micelles can potentially serve as safe and effective MRI contrast agents for detecting tumors that overexpress folate receptors. Keywords: superparamagnetic

The Junkyard in the Jungle: Transnational, Transnatural Nature in Karen Tei Yamashita’s Through the Arc of the Rain Forest

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Begoña Simal

2010-03-01

Full Text Available In this new millennium the relatively young field of ecocriticism has had to face important transdisciplinary, transnational, and transnatural challenges. This article attempts to demonstrate how two of the major changes that environmental criticism is currently undergoing, the transnational turn and the transnatural challenge, have both been encoded in Through the Arc of the Rain Forest (1990, the first novel published by Karen Tei Yamashita. I particularly focus on a significant episode in Through the Arc of the Rain Forest, when a peculiar anthropogenic ecosystem is discovered, and interpret it according to Leo Marx’s classic paradigm of “the machine in the garden.” I intend to prove that Yamashita’s novel not only revisits the old master theory but also revamps it by destabilizing the classic human-nature divide inherent in first-wave ecocriticism and by adding the transnational ingredient. Thus, the machine-in-the-garden paradigm is updated in order to incorporate the broadening of current environmental criticism, both literally (globalization and conceptually (transnatural nature. While at times Marx’s paradigm may metamorphose in intriguing ways, the old trope also corroborates its continuing validity. Though filtered by the sieve of globalization and shaken by the emergence of cyborg ecosystems, “the machine in the garden” has survived as a compelling ecocritical framework, even if it occasionally mutates into a junkyard in the jungle.

Comparison of analyzer-based imaging computed tomography extraction algorithms and application to bone-cartilage imaging

International Nuclear Information System (INIS)

Diemoz, Paul C; Bravin, Alberto; Coan, Paola; Glaser, Christian

2010-01-01

In x-ray phase-contrast analyzer-based imaging, the contrast is provided by a combination of absorption, refraction and scattering effects. Several extraction algorithms, which attempt to separate and quantify these different physical contributions, have been proposed and applied. In a previous work, we presented a quantitative comparison of five among the most well-known extraction algorithms based on the geometrical optics approximation applied to planar images: diffraction-enhanced imaging (DEI), extended diffraction-enhanced imaging (E-DEI), generalized diffraction-enhanced imaging (G-DEI), multiple-image radiography (MIR) and Gaussian curve fitting (GCF). In this paper, we compare these algorithms in the case of the computed tomography (CT) modality. The extraction algorithms are applied to analyzer-based CT images of both plastic phantoms and biological samples (cartilage-on-bone cylinders). Absorption, refraction and scattering signals are derived. Results obtained with the different algorithms may vary greatly, especially in the case of large refraction angles. We show that ABI-CT extraction algorithms can provide an excellent tool to enhance the visualization of cartilage internal structures, which may find applications in a clinical context. Besides, by using the refraction images, the refractive index decrements for both the cartilage matrix and the cartilage cells have been estimated.

Correlation between the Quantifiable Parameters of Whole Solitary Pulmonary Nodules Perfusion Imaging Derived with Dynamic CT and Nodules Size

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Shiyuan LIU

2009-05-01

Full Text Available Background and objective The solitary pulmonary nodules (SPNs is one of the most common findings on chest radiographs. The blood flow patterns of the biggest single SPNs level has been studied. This assessment may be only a limited sample of the entire region of interest (ROI and is unrepresentative of the SPNs as a volume. Ideally, SPNs volume perfusion should be measured. The aim of this study is to evaluate the correlation between the quantifiableparameters of SPNs volume perfusion imaging derived with 16-slice spiral CT and 64-slice spiral CT and nodules size. Methods Sixty-five patients with SPNs (diameter≤3 cm; 42 malignant; 12 active inflammatory; 11 benign underwent multi-location dynamic contrast material-enhanced serial CT scanning mode with stable table were performed; The mean values of valid sections were calculated, as the quantifiable parameters of volume SPNs perfusion imaging derived with16-slice spiral CT and 64-slice spiral CT. The correlation between the quantifiable parameters of SPNs volume perfusion imaging derived with 16-slice spiral CT and 64-slice spiral CT and nodules size were assessed by means of linear regression analysis. Results No significant correlations were found between the nodules size and each of the peak height (PHSPN (32.15 Hu±14.55 Hu，ratio of peak height of the SPN to that of the aorta (SPN-to-A ratio(13.20±6.18%, perfusion(PSPN (29.79±19.12 mLmin-1100 g-1 and mean transit time (12.95±6.53 s (r =0.081, P =0.419; r =0.089, P =0.487; r =0.167, P =0.077; r =0.023, P =0.880. Conclusion No significant correlations were found between the quantifiable parameters of SPNs volume perfusion imaging derived with 16-slice spiral CT and 64-slice spiral CT and nodules size.

Grafting polyethylenimine with quinoline derivatives for targeted imaging of intracellular Zn2+ and logic gate operations

International Nuclear Information System (INIS)

Pan, Yi; Shi, Yupeng; Chen, Junying; Wong, Chap-Mo; Zhang, Heng; Li, Mei-Jin; Li, Cheuk-Wing; Yi, Changqing

2016-01-01

In this study, a highly sensitive and selective fluorescent Zn 2+ probe which exhibited excellent biocompatibility, water solubility, and cell-membrane permeability, was facilely synthesized in a single step by grafting polyethyleneimine (PEI) with quinoline derivatives. The primary amino groups in the branched PEI can increase water solubility and cell permeability of the probe PEIQ, while quinoline derivatives can specifically recognize Zn 2+ and reduce the potential cytotoxicity of PEI. Basing on fluorescence off-on mechanism, PEIQ demonstrated excellent sensing capability towards Zn 2+ in absolute aqueous solution, where a high sensitivity with a detection limit as low as 38.1 nM, and a high selectivity over competing metal ions and potential interfering amino acids, were achieved. Inspired by these results, elementary logic operations (YES, NOT and INHIBIT) have been constructed by employing PEIQ as the gate while Zn 2+ and EDTA as chemical inputs. Together with the low cytotoxicity and good cell-permeability, the practical application of PEIQ in living cell imaging was satisfactorily demonstrated, emphasizing its wide application in fundamental biology research. - Graphical abstract: The fluorescent Zn 2+ probe, PEIQ, is facilely synthesized by grafting PEI with 8-CAAQ, and demonstrated for the pratical applications in Zn 2+ imaging and implementation of molecular logic operations within biological cells. - Highlights: • PEIQ, fluorescent Zn 2+ probe, is synthesized by grafting PEI with quinoline derivatives. • PEIQ exhibits high sensitivity and selectivity in absolute aqueous solution. • PEIQ is biocompatible, water soluble, and cell-membrane permeable. • Elementary logic operations have been demonstrated for PEIQ/Zn 2+ /EDTA system. • The practical application of PEIQ in living cell imaging is demonstrated.

Prediction Center (CPC) Tropical/ Northern Hemisphere Teleconnection Pattern Index

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Monthly tabulated index of the Tropical/ Northern Hemisphere teleconnection pattern. The data spans the period 1950 to present. The index is derived from a rotated...

Climate Prediction Center (CPC) Pacific Transition Teleconnection Pattern Index

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Monthly tabulated index of the Pacific Transition teleconnection pattern. The data spans the period 1950 to present. The index is derived from a rotated principal...

Climate Prediction Center (CPC) East Atlantic Teleconnection Pattern Index

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Monthly tabulated index of the East Atlantic Teleconnection pattern. The data spans the period 1950 to present. The index is derived from a rotated principal...

Refractive-Index Sensing with Ultrathin Plasmonic Nanotubes

DEFF Research Database (Denmark)

Raza, Søren; Toscano, Giuseppe; Jauho, Antti-Pekka

2013-01-01

We study the refractive-index sensing properties of plasmonic nanotubes with a dielectric core and ultrathin metal shell. The few nanometer thin metal shell is described by both the usual Drude model and the nonlocal hydrodynamic model to investigate the effects of nonlocality. We derive an analy......We study the refractive-index sensing properties of plasmonic nanotubes with a dielectric core and ultrathin metal shell. The few nanometer thin metal shell is described by both the usual Drude model and the nonlocal hydrodynamic model to investigate the effects of nonlocality. We derive...... an analytical expression for the extinction cross section and show how sensing of the refractive index of the surrounding medium and the figure of merit are affected by the shape and size of the nanotubes. Comparison with other localized surface plasmon resonance sensors reveals that the nanotube exhibits...

[Evaluation of circulatory state using pulse oximeter: 2. PI (perfusion index) x PVI (pleth variability index)].

Science.gov (United States)

Kaneda, Toru; Suzuki, Toshiyasu

2009-07-01

Pulse oximeter expressed by SpO2 is used for monitoring respiratory state during operation and in ICU. Perfusion index (PI) and pleth variability index (PVI) as new indexes are calculated from pulse oximeter (Masimo SET Radical-7, Masimo Corp., USA, 1998) waveforms. And these indices were used as parameters to evaluate the circulatory state. For PI calculation, the pulsatile infrared signal is indexed against the nonpulsatile infrared signal and expressed as a percentage. It might thus be of future value in assessment of perioperative changes in peripheral perfusion. PVI is a measure of a dynamic change in PI that occurs during complete respiratory cycle. It might be thought that PVI, an index automatically derived from the pulse oximeter waveform analysis, had potentially clinical applications for noninvasive hypovolemia detection and fluid responsiveness monitoring.

To Image...or Not to Image?

Science.gov (United States)

Bruley, Karina

1996-01-01

Provides a checklist of considerations for installing document image processing with an electronic document management system. Other topics include scanning; indexing; the image file life cycle; benefits of imaging; document-driven workflow; and planning for workplace changes like postsorting, creating a scanning room, redeveloping job tasks and…

Climate Prediction Center (CPC) West Pacific Teleconnection Pattern Index

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Monthly tabulated index of the West Pacific (WP) teleconnection pattern. The data spans the period 1950 to present. The index is derived from a rotated principal...

A risk index for pediatric patients undergoing diagnostic imaging with 99mTc-dimercaptosuccinic acid that accounts for body habitus

Science.gov (United States)

O'Reilly, Shannon E.; Plyku, Donika; Sgouros, George; Fahey, Frederic H.; Treves, S. Ted; Frey, Eric C.; Bolch, Wesley E.

2016-03-01

Published guidelines for administered activity to pediatric patients undergoing diagnostic nuclear medicine imaging are currently obtained through expert consensus of the minimum values as a function of body weight as required to yield diagnostic quality images. We have previously shown that consideration of body habitus is also important in obtaining diagnostic quality images at the lowest administered activity. The objective of this study was to create a series of computational phantoms that realistically portray the anatomy of the pediatric patient population which can be used to develop and validate techniques to minimize radiation dose while maintaining adequate image quality. To achieve this objective, we have defined an imaging risk index that may be used in future studies to develop pediatric patient dosing guidelines. A population of 48 hybrid phantoms consisting of non-uniform B-spline surfaces and polygon meshes was generated. The representative ages included the newborn, 1 year, 5 year, 10 year and 15 year male and female. For each age, the phantoms were modeled at their 10th, 50th, and 90th height percentile each at a constant 50th weight percentile. To test the impact of kidney size, the newborn phantoms were modeled with the following three kidney volumes:  -15%, average, and  +15%. To illustrate the impact of different morphologies on dose optimization, we calculated the effective dose for each phantom using weight-based 99mTc-DMSA activity administration. For a given patient weight, body habitus had a considerable effect on effective dose. Substantial variations were observed in the risk index between the 10th and 90th percentile height phantoms from the 50th percentile phantoms for a given age, with the greatest difference being 18%. There was a dependence found between kidney size and risk of radiation induced kidney cancer, with the highest risk indices observed in newborns with the smallest kidneys. Overall, the phantoms and techniques

A fractal derivative model for the characterization of anomalous diffusion in magnetic resonance imaging

Science.gov (United States)

Liang, Yingjie; Ye, Allen Q.; Chen, Wen; Gatto, Rodolfo G.; Colon-Perez, Luis; Mareci, Thomas H.; Magin, Richard L.

2016-10-01

Non-Gaussian (anomalous) diffusion is wide spread in biological tissues where its effects modulate chemical reactions and membrane transport. When viewed using magnetic resonance imaging (MRI), anomalous diffusion is characterized by a persistent or 'long tail' behavior in the decay of the diffusion signal. Recent MRI studies have used the fractional derivative to describe diffusion dynamics in normal and post-mortem tissue by connecting the order of the derivative with changes in tissue composition, structure and complexity. In this study we consider an alternative approach by introducing fractal time and space derivatives into Fick's second law of diffusion. This provides a more natural way to link sub-voxel tissue composition with the observed MRI diffusion signal decay following the application of a diffusion-sensitive pulse sequence. Unlike previous studies using fractional order derivatives, here the fractal derivative order is directly connected to the Hausdorff fractal dimension of the diffusion trajectory. The result is a simpler, computationally faster, and more direct way to incorporate tissue complexity and microstructure into the diffusional dynamics. Furthermore, the results are readily expressed in terms of spectral entropy, which provides a quantitative measure of the overall complexity of the heterogeneous and multi-scale structure of biological tissues. As an example, we apply this new model for the characterization of diffusion in fixed samples of the mouse brain. These results are compared with those obtained using the mono-exponential, the stretched exponential, the fractional derivative, and the diffusion kurtosis models. Overall, we find that the order of the fractal time derivative, the diffusion coefficient, and the spectral entropy are potential biomarkers to differentiate between the microstructure of white and gray matter. In addition, we note that the fractal derivative model has practical advantages over the existing models from the

The influence of image reconstruction algorithms on linear thorax EIT image analysis of ventilation

International Nuclear Information System (INIS)

Zhao, Zhanqi; Möller, Knut; Frerichs, Inéz; Pulletz, Sven; Müller-Lisse, Ullrich

2014-01-01

Analysis methods of electrical impedance tomography (EIT) images based on different reconstruction algorithms were examined. EIT measurements were performed on eight mechanically ventilated patients with acute respiratory distress syndrome. A maneuver with step increase of airway pressure was performed. EIT raw data were reconstructed offline with (1) filtered back-projection (BP); (2) the Dräger algorithm based on linearized Newton–Raphson (DR); (3) the GREIT (Graz consensus reconstruction algorithm for EIT) reconstruction algorithm with a circular forward model (GR C ) and (4) GREIT with individual thorax geometry (GR T ). Individual thorax contours were automatically determined from the routine computed tomography images. Five indices were calculated on the resulting EIT images respectively: (a) the ratio between tidal and deep inflation impedance changes; (b) tidal impedance changes in the right and left lungs; (c) center of gravity; (d) the global inhomogeneity index and (e) ventilation delay at mid-dorsal regions. No significant differences were found in all examined indices among the four reconstruction algorithms (p > 0.2, Kruskal–Wallis test). The examined algorithms used for EIT image reconstruction do not influence the selected indices derived from the EIT image analysis. Indices that validated for images with one reconstruction algorithm are also valid for other reconstruction algorithms. (paper)

The influence of image reconstruction algorithms on linear thorax EIT image analysis of ventilation.

Science.gov (United States)

Zhao, Zhanqi; Frerichs, Inéz; Pulletz, Sven; Müller-Lisse, Ullrich; Möller, Knut

2014-06-01

Analysis methods of electrical impedance tomography (EIT) images based on different reconstruction algorithms were examined. EIT measurements were performed on eight mechanically ventilated patients with acute respiratory distress syndrome. A maneuver with step increase of airway pressure was performed. EIT raw data were reconstructed offline with (1) filtered back-projection (BP); (2) the Dräger algorithm based on linearized Newton-Raphson (DR); (3) the GREIT (Graz consensus reconstruction algorithm for EIT) reconstruction algorithm with a circular forward model (GR(C)) and (4) GREIT with individual thorax geometry (GR(T)). Individual thorax contours were automatically determined from the routine computed tomography images. Five indices were calculated on the resulting EIT images respectively: (a) the ratio between tidal and deep inflation impedance changes; (b) tidal impedance changes in the right and left lungs; (c) center of gravity; (d) the global inhomogeneity index and (e) ventilation delay at mid-dorsal regions. No significant differences were found in all examined indices among the four reconstruction algorithms (p > 0.2, Kruskal-Wallis test). The examined algorithms used for EIT image reconstruction do not influence the selected indices derived from the EIT image analysis. Indices that validated for images with one reconstruction algorithm are also valid for other reconstruction algorithms.

Optical CT imaging of solid radiochromic dosimeters in mismatched refractive index solutions using a scanning laser and large area detector.

Science.gov (United States)

Dekker, Kurtis H; Battista, Jerry J; Jordan, Kevin J

2016-08-01

The practical use of the PRESAGE® solid plastic dosimeter is limited by the inconvenience of immersing it in high-viscosity oils to achieve refractive index matching for optical computed tomography (CT) scanning. The oils are slow to mix and difficult to clean from surfaces, and the dosimeter rotation can generate dynamic Schlieren inhomogeneity patterns in the reference liquid, limiting the rotational and overall scan speed. Therefore, it would be beneficial if lower-viscosity, water-based solutions with slightly unmatched refractive index could be used instead. The purpose of this work is to demonstrate the feasibility of allowing mismatched conditions when using a scanning laser system with a large acceptance angle detector. A fiducial-based ray path measurement technique is combined with an iterative CT reconstruction algorithm to reconstruct images. A water based surrounding liquid with a low viscosity was selected for imaging PRESAGE® solid dosimeters. Liquid selection was optimized to achieve as high a refractive index as possible while avoiding rotation-induced Schlieren effects. This led to a refractive index mismatch of 6% between liquid and dosimeters. Optical CT scans were performed with a fan-beam scanning-laser optical CT system with a large area detector to capture most of the refracted rays. A fiducial marker placed on the wall of a cylindrical sample occludes a given light ray twice. With knowledge of the rotation angle and the radius of the cylindrical object, the actual internal path of each ray through the dosimeter can be calculated. Scans were performed with 1024 projections of 512 data samples each, and rays were rebinned to form 512 parallel-beam projections. Reconstructions were performed on a 512 × 512 grid using 100 iterations of the SIRT iterative CT algorithm. Proof of concept was demonstrated with a uniformly attenuating solution phantom. PRESAGE® dosimeters (11 cm diameter) were irradiated with Cobalt-60 irradiator to achieve

Optical CT imaging of solid radiochromic dosimeters in mismatched refractive index solutions using a scanning laser and large area detector

Energy Technology Data Exchange (ETDEWEB)

Dekker, Kurtis H., E-mail: kdekker2@uwo.ca [Department of Medical Biophysics, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario N6A 5C1 (Canada); Battista, Jerry J.; Jordan, Kevin J. [Departments of Medical Biophysics and Oncology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario N6A 5C1, Canada and Department of Physics and Engineering, London Regional Cancer Program, London Health Sciences Centre, 790 Commissioners Road East, London, Ontario N6A 4L6 (Canada)

2016-08-15

Purpose: The practical use of the PRESAGE® solid plastic dosimeter is limited by the inconvenience of immersing it in high-viscosity oils to achieve refractive index matching for optical computed tomography (CT) scanning. The oils are slow to mix and difficult to clean from surfaces, and the dosimeter rotation can generate dynamic Schlieren inhomogeneity patterns in the reference liquid, limiting the rotational and overall scan speed. Therefore, it would be beneficial if lower-viscosity, water-based solutions with slightly unmatched refractive index could be used instead. The purpose of this work is to demonstrate the feasibility of allowing mismatched conditions when using a scanning laser system with a large acceptance angle detector. A fiducial-based ray path measurement technique is combined with an iterative CT reconstruction algorithm to reconstruct images. Methods: A water based surrounding liquid with a low viscosity was selected for imaging PRESAGE® solid dosimeters. Liquid selection was optimized to achieve as high a refractive index as possible while avoiding rotation-induced Schlieren effects. This led to a refractive index mismatch of 6% between liquid and dosimeters. Optical CT scans were performed with a fan-beam scanning-laser optical CT system with a large area detector to capture most of the refracted rays. A fiducial marker placed on the wall of a cylindrical sample occludes a given light ray twice. With knowledge of the rotation angle and the radius of the cylindrical object, the actual internal path of each ray through the dosimeter can be calculated. Scans were performed with 1024 projections of 512 data samples each, and rays were rebinned to form 512 parallel-beam projections. Reconstructions were performed on a 512 × 512 grid using 100 iterations of the SIRT iterative CT algorithm. Proof of concept was demonstrated with a uniformly attenuating solution phantom. PRESAGE® dosimeters (11 cm diameter) were irradiated with Cobalt-60

T2-weighted MRI-derived textural features reflect prostate cancer aggressiveness: preliminary results.

Science.gov (United States)

Nketiah, Gabriel; Elschot, Mattijs; Kim, Eugene; Teruel, Jose R; Scheenen, Tom W; Bathen, Tone F; Selnæs, Kirsten M

2017-07-01

To evaluate the diagnostic relevance of T2-weighted (T2W) MRI-derived textural features relative to quantitative physiological parameters derived from diffusion-weighted (DW) and dynamic contrast-enhanced (DCE) MRI in Gleason score (GS) 3+4 and 4+3 prostate cancers. 3T multiparametric-MRI was performed on 23 prostate cancer patients prior to prostatectomy. Textural features [angular second moment (ASM), contrast, correlation, entropy], apparent diffusion coefficient (ADC), and DCE pharmacokinetic parameters (K trans and V e ) were calculated from index tumours delineated on the T2W, DW, and DCE images, respectively. The association between the textural features and prostatectomy GS and the MRI-derived parameters, and the utility of the parameters in differentiating between GS 3+4 and 4+3 prostate cancers were assessed statistically. ASM and entropy correlated significantly (p textural features correlated insignificantly with K trans and V e . GS 4+3 cancers had significantly lower ASM and higher entropy than 3+4 cancers, but insignificant differences in median ADC, K trans , and V e . The combined texture-MRI parameters yielded higher classification accuracy (91%) than the individual parameter sets. T2W MRI-derived textural features could serve as potential diagnostic markers, sensitive to the pathological differences in prostate cancers. • T2W MRI-derived textural features correlate significantly with Gleason score and ADC. • T2W MRI-derived textural features differentiate Gleason score 3+4 from 4+3 cancers. • T2W image textural features could augment tumour characterization.

Mapping the Salinity Gradient in a Microfluidic Device with Schlieren Imaging

Directory of Open Access Journals (Sweden)

Chen-li Sun

2015-05-01

Full Text Available This work presents the use of the schlieren imaging to quantify the salinity gradients in a microfluidic device. By partially blocking the back focal plane of the objective lens, the schlieren microscope produces an image with patterns that correspond to spatial derivative of refractive index in the specimen. Since salinity variation leads to change in refractive index, the fluid mixing of an aqueous salt solution of a known concentration and water in a T-microchannel is used to establish the relation between salinity gradients and grayscale readouts. This relation is then employed to map the salinity gradients in the target microfluidic device from the grayscale readouts of the corresponding micro-schlieren image. For saline solution with salinity close to that of the seawater, the grayscale readouts vary linearly with the salinity gradient, and the regression line is independent of the flow condition and the salinity of the injected solution. It is shown that the schlieren technique is well suited to quantify the salinity gradients in microfluidic devices, for it provides a spatially resolved, non-invasive, full-field measurement.

A universal color image quality metric

NARCIS (Netherlands)

Toet, A.; Lucassen, M.P.

2003-01-01

We extend a recently introduced universal grayscale image quality index to a newly developed perceptually decorrelated color space. The resulting color image quality index quantifies the distortion of a processed color image relative to its original version. We evaluated the new color image quality

Vegetation index analysis of multi-source remote sensing data in coal mine wasteland

Energy Technology Data Exchange (ETDEWEB)

Han, Y.X.; Li, M.Z.; Li, D.L. [China Agricultural University, Beijing (China)

2007-12-15

Thirty-six soil samples were collected and their hyperspectral data used to calculate vegetation indices such as a normalised difference vegetation index (NDVI) and a difference vegetation index (DVI). These were evaluated for typical surface object features within the wastelands around Haizhou Opencast Coal Mine in Fuxin city. A principal component analysis to the hyperspectral data was performed, and the result showed that the first and the second principal components satisfactorily accounted for the multi-spectral image information. The panchromatic and multi-spectral images of SPOT5 were then merged. The panchromatic image replaced the first principal component to improve spatial resolution of the image. In addition, the multispectral images and the NDVI image were classified into six types using the unsupervised classification method. The linear quantitative models were built up and the highest correlation coefficients were obtained between the hyperspectral vegetation index and the vegetation index data from the SPOT5 image. The results show that the hyperspectral data and remote sensing images can be used for quantitative estimation of soil nutrients in coal mine wasteland. They can also provide large area surface information for fast and effective decision making regarding revegetation and the monitoring of dynamic change.

Launching Markets for Stock Index Futures and Options: Case of Korea

OpenAIRE

Yu-Kyung Kim

1998-01-01

This paper discusses experiences on launching Korea’s first-ever regulated derivatives market, namely stock index futures, on May 3, 1996, and subsequent opening of a stock index options market on July 7, 1997. It illustrates what went on as the Korea Stock Exchange was making a decision on its opening and describes the current status of the derivatives market.

Compostos voláteis dos frutos de maracujá (Passiflora edulis forma Flavicarpa e de cajá (Spondias mombin L. obtidos pela técnica de headspace dinâmico Volatile compounds in passion fruit (Passiflora edulis forma Flavicarpa and yellow mombin (Spondias mombin L. fruits obtained by dynamic headspace technique

Directory of Open Access Journals (Sweden)

Nerendra Narain

2004-06-01

Full Text Available Entre as inúmeras frutas tropicais e subtropicais produzidas no Brasil, duas que se destacam do ponto de vista do aroma da polpa são maracujá amarelo (Passiflora edulis forma Flavicarpa e cajá (Spondias mombin L.. Os voláteis da polpa destas frutas foram capturados pela técnica de headspace dinâmico e analisados no sistema de cromatografia gasosa de alta resolução e espectrometria de massa. Foram identificados 48 e 33 compostos voláteis na polpa de maracujá e cajá, respectivamente. Os compostos voláteis predominantes na polpa de maracujá pertenceram às classes de ésteres (59,24%, aldeídos (15,27%, cetonas (11,70% e álcoois (6,56%, enquanto na polpa de cajá as principais classes de compostos foram de ésteres (48,76%, álcoois (21,69%, aldeídos (11,61% e cetonas (4,19%. Outros compostos aromáticos característicos foram para maracujá: beta-ionona e linalol e para cajá: gama-octalactona e ácidos butírico e hexanóico.Among the numerous tropical and sub-tropical fruits produced in Brazil, two that attain relatively greater importance from the point of view of aroma of their pulp are yellow passion fruit (Passiflora edulis forma Flavicarpa and yellow mombin (Spondias mombin L.. The volatile components in the pulp of these fruits were captured by dynamic headspace technique and were analyzed in a system of high-resolution gas chromatography and mass spectrometry. Forty-eight and thirty-one volatile compounds were identified in passion fruit and yellow mombin fruit pulp, respectively. The predominant volatile compounds in passion fruit pulp belonged to the classes of esters (59.24%, aldehydes (15.27%, ketones (11.70% and alcohols (6.56% while in the yellow mombin pulp, the principal classes of compounds were esters (48.76%, alcohols (21.69%. aldehydes (11.61% and ketones (4.19%. The other characteristic aroma compounds for passion fruit were beta-ionone and linalool and for yellow mombin were gamma-octalactone, butanoic and

Identificação e quantificação de voláteis de café através de cromatografia gasosa de alta resolução / espectrometria de massas empregando um amostrador automático de "headspace" Identification and quantification of coffee volatile components through high resolution gas chromatoghaph/mass spectrometer using a headspace automatic sampler

Directory of Open Access Journals (Sweden)

Leonardo César AMSTALDEN

2001-01-01

Full Text Available Usando um amostrador automático, os "headspaces" de três marcas comerciais de café torrado e moído foram analisados qualitativa e quantitativamente quanto a composição dos voláteis responsáveis pelo aroma através da técnica de cromatografia gasosa/espectrometria de massas. Uma vez que a metodologia não envolveu isolamento ou concentração dos aromas, suas proporções naturais foram mantidas, além de simplificar o preparo das amostras. O emprego do amostrador automático permitiu também boa resolução dos picos cromatográficos sem o emprego de criogenia, contribuindo para redução no tempo de análise. Noventa e um componentes puderam ser identificados, sendo que alguns compostos conhecidos como presentes em café como o dimetilsulfeto, metional e furfuril mercaptana não foram detectados. Os voláteis presentes em maior concentração puderam ser quantificados com o auxílio de dois padrões internos. A técnica se provou viável, tanto para caracterização como para quantificação de voláteis de café.Employing an automatic headspace sampler, the headspaces of three commercial brands of ground roasted coffee were qualitatively and quantitatively analyzed by gas chromatography / mass spectrometry. Since the methodology did not involve aroma isolation or concentration, their natural proportions were maintained, providing a more accurate composition of the flavors, and simplifying sample preparation. The automatic sampler allowed good resolution of the chromatographic peaks without cryofocusing the samples at the head of the column during injection, reducing analysis time. Ninety one compounds were identified and some known coffee volatiles, such as dimethyl sulphide, methional and furfuryl mercaptan were not detected. The more concentrated volatiles could be identified using two internal standards. The technique proved viable, for both characterization and for quantification of coffee volatiles.

Oriented Shape Index Histograms for Cell Classification

DEFF Research Database (Denmark)

Larsen, Anders Boesen Lindbo; Dahl, Anders Bjorholm; Larsen, Rasmus

2015-01-01

We propose a novel extension to the shape index histogram feature descriptor where the orientation of the second-order curvature is included in the histograms. The orientation of the shape index is reminiscent but not equal to gradient orientation which is widely used for feature description. We...... evaluate our new feature descriptor using a public dataset consisting of HEp-2 cell images from indirect immunoflourescence lighting. Our results show that we can improve classification performance significantly when including the shape index orientation. Notably, we show that shape index orientation...

Image-derived input function in dynamic human PET/CT: methodology and validation with 11C-acetate and 18F-fluorothioheptadecanoic acid in muscle and 18F-fluorodeoxyglucose in brain

International Nuclear Information System (INIS)

Croteau, Etienne; Lavallee, Eric; Hubert, Laurent; Rousseau, Jacques A.; Lecomte, Roger; Labbe, Sebastien M.; Carpentier, Andre C.; Pifferi, Fabien; Cunnane, Stephen C.; Benard, Francois

2010-01-01

Despite current advances in PET/CT systems, blood sampling still remains the standard method to obtain the radiotracer input function for tracer kinetic modelling. The purpose of this study was to validate the use of image-derived input functions (IDIF) of the carotid and femoral arteries to measure the arterial input function (AIF) in PET imaging. The data were obtained from two different research studies, one using 18 F-FDG for brain imaging and the other using 11 C-acetate and 18 F-fluoro-6-thioheptadecanoic acid ( 18 F-FTHA) in femoral muscles. The method was validated with two phantom systems. First, a static phantom consisting of syringes of different diameters containing radioactivity was used to determine the recovery coefficient (RC) and spill-in factors. Second, a dynamic phantom built to model bolus injection and clearance of tracers was used to establish the correlation between blood sampling, AIF and IDIF. The RC was then applied to the femoral artery data from PET imaging studies with 11 C-acetate and 18 F-FTHA and to carotid artery data from brain imaging with 18 F-FDG. These IDIF data were then compared to actual AIFs from patients. With 11 C-acetate, the perfusion index in the femoral muscle was 0.34±0.18 min -1 when estimated from the actual time-activity blood curve, 0.29±0.15 min -1 when estimated from the corrected IDIF, and 0.66±0.41 min -1 when the IDIF data were not corrected for RC. A one-way repeated measures (ANOVA) and Tukey's test showed a statistically significant difference for the IDIF not corrected for RC (p 18 F-FTHA there was a strong correlation between Patlak slopes, the plasma to tissue transfer rate calculated using the true plasma radioactivity content and the corrected IDIF for the femoral muscles (vastus lateralis r=0.86, p=0.027; biceps femoris r=0.90, p=0.017). On the other hand, there was no correlation between the values derived using the AIF and those derived using the uncorrected IDIF. Finally, in the brain imaging

Weather Derivatives – Origin, Types and Application

Directory of Open Access Journals (Sweden)

Piotr Binkowski

2008-01-01

Full Text Available The number of companies that are exposed to the revenues loss risk caused by weather variability is still increasing. The businesses that are mostly exposed to weather risk are following: energy, agriculture, constructions and transport. That situation has initiated dynamic growth of weather derivatives markets as well as the awareness of the weather risk among the market participants. Presently, the weather derivatives markets evaluate rapidly in all the mature economies: USA, Asia and Europe. Constructing weather derivatives relies on qu- antifying climate factors in the form of indexes, what is quite simple task, more difficultly can be gathering precise historical data of required climate factors. Taking into consideration so far development of derivatives especially the financial derivatives based on different types of indexes financial market has at disposal wide range of different types of proved derivatives (futures, forward, options, swaps, which can be successfully utilised on the weather-driven markets both for hedging weather risk and speculating.

Intra- and interspecific variation in tropical tree and liana phenology derived from Unmanned Aerial Vehicle images

Science.gov (United States)

Bohlman, S.; Park, J.; Muller-Landau, H. C.; Rifai, S. W.; Dandois, J. P.

2017-12-01

Phenology is a critical driver of ecosystem processes. There is strong evidence that phenology is shifting in temperate ecosystems in response to climate change, but tropical tree and liana phenology remains poorly quantified and understood. A key challenge is that tropical forests contain hundreds of plant species with a wide variety of phenological patterns. Satellite-based observations, an important source of phenology data in northern latitudes, are hindered by frequent cloud cover in the tropics. To quantify phenology over a large number of individuals and species, we collected bi-weekly images from unmanned aerial vehicles (UAVs) in the well-studied 50-ha forest inventory plot on Barro Colorado Island, Panama. Between October 2014 and December 2015 and again in May 2015, we collected a total of 35 sets of UAV images, each with continuous coverage of the 50-ha plot, where every tree ≥ 1 cm DBH is mapped. Spectral, texture, and image information was extracted from the UAV images for individual tree crowns, which was then used as inputs for a machine learning algorithm to predict percent leaf and branch cover. We obtained the species identities of 2000 crowns in the images via field mapping. The objectives of this study are to (1) determined if machine learning algorithms, applied to UAV images, can effectively quantify changes in leaf cover, which we term "deciduousness; (2) determine how liana cover effects deciduousness and (3) test how well UAV-derived deciduousness patterns match satellite-derived temporal patterns. Machine learning algorithms trained on a variety of image parameters could effectively determine leaf cover, despite variation in lighting and viewing angles. Crowns with higher liana cover have less overall deciduousness (tree + liana together) than crowns with lower liana cover. Individual crown deciduousness, summed over all crowns measured in the 50-ha plot, showed a similar seasonal pattern as MODIS EVI composited over 10 years. However

Proposal for a remote sensing trophic state index based upon Thematic Mapper/Landsat images

Directory of Open Access Journals (Sweden)

Evlyn Márcia Leão de Moraes Novo

2013-12-01

Full Text Available This work proposes a trophic state index based on the remote sensing retrieval of chlorophyll-α concentration. For that, in situ Bidirectional Reflectance Factor (BRF data acquired in the Ibitinga reservoir were resampled to match Landsat/TM spectral simulated bands (TM_sim bands and used to run linear correlation with concurrent measurements of chlorophyll-α concentration. Monte Carlo simulation was then applied to select the most suitable model relating chlorophyll-α concentration and simulated TM/Landsat reflectance. TM4_sim/TM3_sim ratio provided the best model with a R2 value of 0.78. The model was then inverted to create a look-up-table (LUT relating TM4_sim/TM3_sim ratio intervals to chlorophyll-α concentration trophic state classes covering the entire range measured in the reservoir. Atmospheric corrected Landsat TM images converted to surface reflectance were then used to generate a TM4/TM3 ratio image. The ratio image frequency distribution encompassed the range of TM4_sim/TM3_sim ratio indicating agreement between in situ and satellite data and supporting the use of satellite data to map chlorophyll- concentration trophic state distribution in the reservoir. Based on that, the LUT was applied to a Landsat/TM ratio image to map the spatial distribution of chlorophyll- trophic state classes in Ibitinga reservoir. Despite the stochastic selection of TM4_sim/TM3_sim ratio as the best input variable for modeling the chlorophyll-α concentration, it has a physical basis: high concentration of phytoplankton increases the reflectance in the near-infrared (TM4 and decreases the reflectance in the red (TM3. The band ratio, therefore, enhances the relationship between chlorophyll- concentration and remotely sensed reflectance.

CERN featured as leader in Global Innovation Index

CERN Multimedia

Anaïs Rassat, KT group

2016-01-01

The Global Innovation Index 2016 report is a leading reference on innovation and uses CERN as an example of a highly successful regional initiative.   The Global Innovation Index 2016 (GII) report highlights CERN’s successful innovation initiatives. (Image: GII) Read more here.

Counting the mismatches - lung ventilation/perfusion subtraction index

International Nuclear Information System (INIS)

Anderson, T.C.; Evans, S.G.; Larcos, G.; Farlow, D.C.

1998-01-01

Full text: There is potential for interobserver variability in interpretation of ventilation/perfusion (V/Q) scans. Objective quantification of V/Q mismatch could be useful. Thus, the aim of this study is to determine the validity of image subtraction in a group of 27 patients (11 men, 8 women; mean age 59.4 years [range 21-81 years])investigated by V/Q scans for suspected pulmonary emboli. A standard 6 view V/Q scan was obtained with two cobalt markers used on the anterior and posterior surfaces for image alignment. Ventilation images were normalised to the perfusion using an area of normal ventilation and perfusion. With the use of automated, and if required, manual alignment, perfusion images were subtracted from ventilation, with a median filter applied. A summed index of mismatch for each lung scan was calculated from the difference. This index was then retrospectively compared to the result reported by one of four experienced physicians. Two patients with chronic obstructive airways disease were excluded from analysis. We conclude that high probability V/Q scans can be differentiated from low probability studies using this index; further prospective investigation in a larger cohort is warranted

A risk index for pediatric patients undergoing diagnostic imaging with 99mTc-dimercaptosuccinic acid that accounts for body habitus

International Nuclear Information System (INIS)

O’Reilly, Shannon E; Plyku, Donika; Sgouros, George; Frey, Eric C; Fahey, Frederic H; Ted Treves, S; Bolch, Wesley E

2016-01-01

Published guidelines for administered activity to pediatric patients undergoing diagnostic nuclear medicine imaging are currently obtained through expert consensus of the minimum values as a function of body weight as required to yield diagnostic quality images. We have previously shown that consideration of body habitus is also important in obtaining diagnostic quality images at the lowest administered activity. The objective of this study was to create a series of computational phantoms that realistically portray the anatomy of the pediatric patient population which can be used to develop and validate techniques to minimize radiation dose while maintaining adequate image quality. To achieve this objective, we have defined an imaging risk index that may be used in future studies to develop pediatric patient dosing guidelines. A population of 48 hybrid phantoms consisting of non-uniform B-spline surfaces and polygon meshes was generated. The representative ages included the newborn, 1 year, 5 year, 10 year and 15 year male and female. For each age, the phantoms were modeled at their 10th, 50th, and 90th height percentile each at a constant 50th weight percentile. To test the impact of kidney size, the newborn phantoms were modeled with the following three kidney volumes:  −15%, average, and  +15%. To illustrate the impact of different morphologies on dose optimization, we calculated the effective dose for each phantom using weight-based 99m Tc-DMSA activity administration. For a given patient weight, body habitus had a considerable effect on effective dose. Substantial variations were observed in the risk index between the 10th and 90th percentile height phantoms from the 50th percentile phantoms for a given age, with the greatest difference being 18%. There was a dependence found between kidney size and risk of radiation induced kidney cancer, with the highest risk indices observed in newborns with the smallest kidneys. Overall, the phantoms and

Correlating two-photon excited fluorescence imaging of breast cancer cellular redox state with seahorse flux analysis of normalized cellular oxygen consumption

Science.gov (United States)

Hou, Jue; Wright, Heather J.; Chan, Nicole; Tran, Richard; Razorenova, Olga V.; Potma, Eric O.; Tromberg, Bruce J.

2016-06-01

Two-photon excited fluorescence (TPEF) imaging of the cellular cofactors nicotinamide adenine dinucleotide and oxidized flavin adenine dinucleotide is widely used to measure cellular metabolism, both in normal and pathological cells and tissues. When dual-wavelength excitation is used, ratiometric TPEF imaging of the intrinsic cofactor fluorescence provides a metabolic index of cells-the "optical redox ratio" (ORR). With increased interest in understanding and controlling cellular metabolism in cancer, there is a need to evaluate the performance of ORR in malignant cells. We compare TPEF metabolic imaging with seahorse flux analysis of cellular oxygen consumption in two different breast cancer cell lines (MCF-7 and MDA-MB-231). We monitor metabolic index in living cells under both normal culture conditions and, for MCF-7, in response to cell respiration inhibitors and uncouplers. We observe a significant correlation between the TPEF-derived ORR and the flux analyzer measurements (R=0.7901, p<0.001). Our results confirm that the ORR is a valid dynamic index of cell metabolism under a range of oxygen consumption conditions relevant for cancer imaging.

Fast and efficient indexing approach for object recognition

Science.gov (United States)

Hefnawy, Alaa; Mashali, Samia A.; Rashwan, Mohsen; Fikri, Magdi

1999-08-01

This paper introduces a fast and efficient indexing approach for both 2D and 3D model-based object recognition in the presence of rotation, translation, and scale variations of objects. The indexing entries are computed after preprocessing the data by Haar wavelet decomposition. The scheme is based on a unified image feature detection approach based on Zernike moments. A set of low level features, e.g. high precision edges, gray level corners, are estimated by a set of orthogonal Zernike moments, calculated locally around every image point. A high dimensional, highly descriptive indexing entries are then calculated based on the correlation of these local features and employed for fast access to the model database to generate hypotheses. A list of the most candidate models is then presented by evaluating the hypotheses. Experimental results are included to demonstrate the effectiveness of the proposed indexing approach.

One-Step 18F-Labeling of Estradiol Derivative for PET Imaging of Breast Cancer

Directory of Open Access Journals (Sweden)

Hongbo Huang

2018-01-01

Full Text Available Positron emission tomography (PET imaging is a useful method to evaluate in situ estrogen receptor (ER status for the early diagnosis of breast cancer and optimization of the appropriate treatment strategy. The 18F-labeled estradiol derivative has been successfully used to clinically assess the ER level of breast cancer. In order to simplify the radiosynthesis process, one-step 18F-19F isotope exchange reaction was employed for the 18F-fluorination of the tracer of [18F]AmBF3-TEG-ES. The radiotracer was obtained with the radiochemical yield (RCY of ~61% and the radiochemical purity (RCP of >98% within 40 min. Cell uptake and blocking assays indicated that the tracer could selectively accumulate in the ER-positive human breast cancer cell lines MCF-7 and T47D. In vivo PET imaging on the MCF-7 tumor-bearing mice showed relatively high tumor uptake (1.4~2.3 %D/g and tumor/muscle uptake ratio (4~6. These results indicated that the tracer is a promising PET imaging agent for ER-positive breast cancers.

Atmospheric effects on the NDVI - Strategies for its removal. [Normalized Difference Vegetation Index

Science.gov (United States)

Kaufman, Y. J.; Tanre, D.; Holben, B. N.; Markham, B.; Gitelson, A.

1992-01-01

The compositing technique used to derive global vegetation index (NDVI) from the NOAA AVHRR radiances reduces the residual effect of water vapor and aerosol on the NDVI. The reduction in the atmospheric effect is shown using a comprehensive measured data set for desert conditions, and a simulation for grass with continental aerosol. A statistical analaysis of the probability of occurrence of aerosol optical thickness and precipitable water vapor measured in different climatic regimes is used for this simulation. It is concluded that for a long compositing period (e.g., 27 days), the residual aerosol optical thickness and precipitable water vapor are usually too small to be corrected. For a 9-day compositing, the residual average aerosol effect may be about twice the correction uncertainty. For Landsat TM or Earth Observing System Moderate Resolution Imaging Spectrometer (EOS-MODIS) data, the newly defined atmospherically resistant vegetation index (ARVI) is more promising than possible direct atmospheric correction schemes, except for heavy desert dust conditions.

Alterações contráteis segmentares e sua associação com arritmias ventriculares complexas, em pacientes chagásicos com eletrocardiograma normal ou borderline Regional left ventricular dysfunction and its association with complex ventricular arrhythmia, in chagasic patients with normal or borderline electrocardiogram

Directory of Open Access Journals (Sweden)

Flavia Vernin de Oliveira Terzi

2010-10-01

Full Text Available INTRODUÇÃO: Morte súbita representa a principal causa de óbito em chagásicos. Eventos fatais em pacientes saudáveis, com anormalidades contráteis, foram documentados. O objetivo deste trabalho é determinar a associação entre alteração contrátil e arritmias ventriculares complexas em pacientes chagásicos, classe funcional I, eletrocardiograma normal ou borderline e função ventricular preservada. MÉTODOS: Quarenta e nove pacientes com doença de Chagas e eletrocardiograma normal ou borderline realizaram ecocardiograma, teste ergométrico e Holter. Avaliou-se a contratilidade global e segmentar dos ventrículos e a presença de arritmias ventriculares complexas induzidas no esforço e espontâneas, respectivamente. A análise estatística foi feita pelo modelo Log-Linear geral. RESULTADOS: Idade média de 56 anos; 55% mulheres. Alterações contráteis segmentares em 24,5% dos pacientes; 12% dos Holter e 18% dos testes ergométricos positivos. Houve associação entre arritmia e alteração segmentar condicionada à presença da disfunção sistólica leve do ventrículo esquerdo. CONCLUSÕES: Alterações contráteis, na presença de disfunção global leve, indicam pacientes sob maior risco de arritmias complexas.INTRODUCTION: Sudden death is the major cause of death among chagasic patients. A significant number of fatal events in patients without apparent heart disease and borderline electrocardiogram, but with contractile ventricular dysfunction, have been documented. This work aimed to determine the association between regional dysfunction and the presence of ventricular arrhythmia in chagasic patients without apparent heart disease. METHODS: Forty-nine patients with normal or borderline electrocardiogram were submitted to echocardiogram, exercise stress test and Holter. The presence of cardiac contractile alterations and complex ventricular arrhythmia was analyzed. Statistic analysis used the general Log-Linear model. RESULTS

Conditional non-independence of radiographic image features and the derivation of post-test probabilities – A mammography BI-RADS example

International Nuclear Information System (INIS)

Benndorf, Matthias

2012-01-01

Bayes' theorem has proven to be one of the cornerstones in medical decision making. It allows for the derivation of post-test probabilities, which in case of a positive test result become positive predictive values. If several test results are observed successively Bayes' theorem may be used with assumed conditional independence of test results or with incorporated conditional dependencies. Herein it is examined whether radiographic image features should be considered conditionally independent diagnostic tests when post-test probabilities are to be derived. For this purpose the mammographic mass dataset from the UCI (University of California, Irvine) machine learning repository is analysed. It comprises the description of 961 (516 benign, 445 malignant) mammographic mass lesions according to the BI-RADS (Breast Imaging: Reporting and Data System) lexicon. Firstly, an exhaustive correlation matrix is presented for mammography BI-RADS features among benign and malignant lesions separately; correlation can be regarded as measure for conditional dependence. Secondly, it is shown that the derived positive predictive values for the conjunction of the two features “irregular shape” and “spiculated margin” differ significantly depending on whether conditional dependencies are incorporated into the decision process or not. It is concluded that radiographic image features should not generally be regarded as conditionally independent diagnostic tests.

Abordagem terapêutica dos projéteis retidos no coração Management of bullets lodged in the heart

Directory of Open Access Journals (Sweden)

Enoch Brandão de Souza Meira

2005-03-01

Full Text Available Paciente do sexo masculino, 29 anos, apresentando ferimento por arma de fogo, com projétil alojado no coração e que chegou ao hospital hemodinamicamente estável. O diagnóstico, evidenciando a localização da bala, foi feito pelo ecocardiograma transesofágico (ET. Após 18 dias, foi submetido à cirurgia eletiva, sem circulação extracorpórea (CEC, para retirada do projétil encravado em parede anterior do ventrículo direito (VD e septo interventricular (SIV, com sucesso. Os autores discutem a conduta terapêutica para os projéteis retidos no coração, com base na literatura consultada, concluindo que a cirurgia para remoção dos mesmos pode ser indicada em pacientes assintomáticos individualizados.A 29-year-old man presented with a bullet lodged in his heart. He arrived at the hospital in a hemodynamically stable condition. The transesophageal echocardiogram performed for diagnosis revealed the location of the bullet. After 18 days, he underwent an elective off-pump cardiac surgery fto remove the bullet from the right ventricle wall and interventricular septum. The postoperative evolution was uneventful. The authors discuss the therapeutic options for removing bullets from thr heart, based on published data. They concluded that some asymptomatic patients with a bullet embedded in the heart should undergo surgery.

A Field Assessment of a Prototype Meter for Measuring the Wet-Bulb Globe-Thermometer Index

Science.gov (United States)

Walters, J. D.

1968-01-01

A prototype electronic instrument for the direct measurement of the wet-bulb globe-thermometer index is described. An assessment is made of its accuracy, as compared with W.B.G.T. indices calculated from conventional thermometric data, and a comparison is made between W.B.G.T. values read from the meter and effective or corrected effective temperatures derived from separate thermometric and air velocity recording instruments in the same climates. The instrument proved to be reliable and accurate over a wide range of climates and is a useful self-contained device for use in habitability surveys and similar investigations. Images PMID:5663429

Estimating Leaf Area Index for an arid region using Spectral Data ...

African Journals Online (AJOL)

In this study, spectral reflectance of pearl millet was computed at various wavelengths and at different times during the cropping season, using a spectroradiometer. Three main indices (Normalised Difference Vegetation Index, Ratio Vegetation Index, and Perpendicular Vegetation Index)were derived from the spectral data.

Sensitivity study of land biosphere CO2 exchange through an atmospheric tracer transport model using satellite-derived vegetation index data

International Nuclear Information System (INIS)

Knorr, W.; Heimann, M.

1994-01-01

We develop a simple, globally uniform model of CO 2 exchange between the atmosphere and the terrestrial biosphere by coupling the model with a three-dimensional atmospheric tracer transport model using observed winds, and checking results against observed concentrations of CO 2 at various monitoring sites. CO 2 fluxes are derived from observed greenness using satellite-derived Global Vegetation Index data, combined with observations of temperature, radiation, and precipitation. We explore a range of CO 2 flux formulations together with some modifications of the modelled atmospheric transport. We find that while some formulations can be excluded, it cannot be decided whether or not to make CO 2 uptake and release dependent on water stress. It appears that the seasonality of net CO 2 fluxes in the tropics, which would be expected to be driven by water availability, is small and is therefore not visible in the seasonal cycle of atmospheric CO 2 . The latter is dominated largely by northern temperate and boreal vegetation, where seasonality is mostly temperature determined. We find some evidence that there is still considerable CO 2 release from soils during northern-hemisphere winter. An exponential air temperature dependence of soil release with a Q 10 of 1.5 is found to be most appropriate, with no cutoff at low freezing temperatures. This result is independent of the year from which observed winds were taken. This is remarkable insofar as year-to-year changes in modelled CO 2 concentrations caused by changes in the wind data clearly outweigh those caused by year-to-year variability in the climate and vegetation index data. (orig.)

Performing derivative and integral operations for optical waves with optical metamaterials

Energy Technology Data Exchange (ETDEWEB)

Dai, Cun-Li [College of Engineering, Nanjing Agriculture University, Nanjing Jiangsu, 210031 (China); College of Science, Nanjing Agriculture University, Nanjing Jiangsu, 210095 (China); Zhao, Zhi-Gang; Li, Xiao-Lin [College of Engineering, Nanjing Agriculture University, Nanjing Jiangsu, 210031 (China); Yang, Hong-Wei, E-mail: phd_hwyang@njau.edu.cn [College of Science, Nanjing Agriculture University, Nanjing Jiangsu, 210095 (China)

2016-12-01

The graded refractive index waveguides can perform Fourier transform for an optical wave. According to this characteristic, simpler optical metamaterials with three waveguides are theoretically proposed, in which all of the waveguides are materials with a positive refractive index. By selecting the appropriate refractive index and structure size, the theory and simulations demonstrated that these metamaterials can perform mathematical operations for the outline of incident optical waves, including the first-order derivative, second-order derivative and the integral. - Highlights: • The derivative and integral operations of optical waves are achieved with a simpler model. • Both negative and positive refractive index boast the same functions. • The mathematical operations can be implemented only by changing the refractive index of the intermediate material. • The results will greatly expand the possible applications, including photon computers, picture processing, video displays and data storage.

Quantitative measurement of hepatic fibrosis with gadoxetic acid-enhanced magnetic resonance imaging in patients with chronic hepatitis B infection: A comparative study on aspartate aminotransferase to platelet ratio index and fibrosis-4 index

International Nuclear Information System (INIS)

Lee, Guy Mok; Kim, Youe Ree; Cho, Eun Young; Lee, Young Hwan; Yoon, Kwon Ha; Ryu, Jong Hyun; Kim, Tae Hoon

2017-01-01

To quantitatively measure hepatic fibrosis on gadoxetic acid-enhanced magnetic resonance (MR) in chronic hepatitis B (CHB) patients and identify the correlations with aspartate aminotransferase-to-platelet ratio index (APRI) and fibrosis-4 index (FIB-4) values. This study on gadoxetic acid-enhanced 3T MR imaging included 81 patients with CHB infection. To quantitatively measure hepatic fibrosis, MR images were analyzed with an aim to identify inhomogeneous signal intensities calculated from a coefficient of variation (CV) map in the liver parenchyma. We also carried out a comparative analysis between APRI and FIB-4 based on metaregression results. The diagnostic performance of the CV map was evaluated using a receiver-operating characteristic (ROC) curve. In the MR images, the mean CV values in control, groups I, II, and III based on APRI were 4.08 ± 0.92, 4.24 ± 0.80, 5.64 ± 1.11, and 5.73 ± 1.28, respectively (p < 0.001). In CHB patients grouped by FIB-4, the mean CV values of groups A, B, and C were 4.22 ± 0.95, 5.40 ± 1.19, and 5.71 ± 1.17, respectively (p < 0.001). The mean CV values correlated well with APRI (r = 0.392, p < 0.001) and FIB-4 (r = 0.294, p < 0.001). In significant fibrosis group, ROC curve analysis yielded an area under the curve of 0.875 using APRI and 0.831 using FIB-4 in HB, respectively. Gadoxetic acid-enhanced MR imaging for calculating a CV map showed moderate correlation with APRI and FIB-4 values and could be employed to quantitatively measure hepatic fibrosis in patients with CHB

Quantitative measurement of hepatic fibrosis with gadoxetic acid-enhanced magnetic resonance imaging in patients with chronic hepatitis B infection: A comparative study on aspartate aminotransferase to platelet ratio index and fibrosis-4 index

Energy Technology Data Exchange (ETDEWEB)

Lee, Guy Mok; Kim, Youe Ree; Cho, Eun Young; Lee, Young Hwan; Yoon, Kwon Ha [Wonkwang University School of Medicine, Iksan (Korea, Republic of); Ryu, Jong Hyun; Kim, Tae Hoon [Imaging Science Research Center, Wonkwang University, Iksan (Korea, Republic of)

2017-06-15

To quantitatively measure hepatic fibrosis on gadoxetic acid-enhanced magnetic resonance (MR) in chronic hepatitis B (CHB) patients and identify the correlations with aspartate aminotransferase-to-platelet ratio index (APRI) and fibrosis-4 index (FIB-4) values. This study on gadoxetic acid-enhanced 3T MR imaging included 81 patients with CHB infection. To quantitatively measure hepatic fibrosis, MR images were analyzed with an aim to identify inhomogeneous signal intensities calculated from a coefficient of variation (CV) map in the liver parenchyma. We also carried out a comparative analysis between APRI and FIB-4 based on metaregression results. The diagnostic performance of the CV map was evaluated using a receiver-operating characteristic (ROC) curve. In the MR images, the mean CV values in control, groups I, II, and III based on APRI were 4.08 ± 0.92, 4.24 ± 0.80, 5.64 ± 1.11, and 5.73 ± 1.28, respectively (p < 0.001). In CHB patients grouped by FIB-4, the mean CV values of groups A, B, and C were 4.22 ± 0.95, 5.40 ± 1.19, and 5.71 ± 1.17, respectively (p < 0.001). The mean CV values correlated well with APRI (r = 0.392, p < 0.001) and FIB-4 (r = 0.294, p < 0.001). In significant fibrosis group, ROC curve analysis yielded an area under the curve of 0.875 using APRI and 0.831 using FIB-4 in HB, respectively. Gadoxetic acid-enhanced MR imaging for calculating a CV map showed moderate correlation with APRI and FIB-4 values and could be employed to quantitatively measure hepatic fibrosis in patients with CHB.

INDEXABILITY AND OPTIMAL INDEX POLICIES FOR A CLASS OF REINITIALISING RESTLESS BANDITS.

Science.gov (United States)

Villar, Sofía S

2016-01-01

Motivated by a class of Partially Observable Markov Decision Processes with application in surveillance systems in which a set of imperfectly observed state processes is to be inferred from a subset of available observations through a Bayesian approach, we formulate and analyze a special family of multi-armed restless bandit problems. We consider the problem of finding an optimal policy for observing the processes that maximizes the total expected net rewards over an infinite time horizon subject to the resource availability. From the Lagrangian relaxation of the original problem, an index policy can be derived, as long as the existence of the Whittle index is ensured. We demonstrate that such a class of reinitializing bandits in which the projects' state deteriorates while active and resets to its initial state when passive until its completion possesses the structural property of indexability and we further show how to compute the index in closed form. In general, the Whittle index rule for restless bandit problems does not achieve optimality. However, we show that the proposed Whittle index rule is optimal for the problem under study in the case of stochastically heterogenous arms under the expected total criterion, and it is further recovered by a simple tractable rule referred to as the 1-limited Round Robin rule. Moreover, we illustrate the significant suboptimality of other widely used heuristic: the Myopic index rule, by computing in closed form its suboptimality gap. We present numerical studies which illustrate for the more general instances the performance advantages of the Whittle index rule over other simple heuristics.

Dynamic Modeling of CDS Index Tranche Spreads

DEFF Research Database (Denmark)

Dorn, Jochen

This paper provides a Market Model which implies a dynamics for standardized CDS index tranche spreads, i.e. tranches which securitise CDS index series and dispose of predefined subordination. This model is useful for pricing options on tranches with future Issue Dates as well as for modeling...... options on structured credit derivatives. With the upcoming regulation of the CDS market in perspective, the model presented here is also an attempt to face the effects on pricing approaches provoked by an eventual Clearing Chamber . It becomes also possible to calibrate Index Tranche Options with bespoke...... tenors/tranche subordination to market data obtained by more liquid Index Tranche Options with standard characteristics....

Nonperturbative results for two-index conformal windows

Energy Technology Data Exchange (ETDEWEB)

Bergner, Georg [Albert Einstein Center for Fundamental Physics,Institute for Theoretical Physics, University of Bern,Sidlerstrasse 5, CH-3012 Bern (Switzerland); Ryttov, Thomas A.; Sannino, Francesco [CP-Origins and the Danish IAS, University of Southern Denmark,5230 Odense M (Denmark)

2015-12-10

Via large and small N{sub c} relations we derive nonperturbative results about the conformal window of two-index theories. Using Schwinger-Dyson methods as well as four-loops results we estimate subleading corrections and show that naive large number of colors extrapolations are unreliable when N{sub c} is less than about six. Nevertheless useful nonperturbative inequalities for the size of the conformal windows, for any number of colors, can be derived. By further observing that the adjoint conformal window is independent of the number of colors we argue, among other things, that: the large N{sub c} two-index conformal window is twice the conformal window of the adjoint representation (which can be determined at small N{sub c}) expressed in terms of Dirac fermions; lattice results for adjoint matter can be used to provide independent information on the conformal dynamics of two-index theories such as SU(N{sub c}) with two and four symmetric Dirac flavors.

Nonperturbative results for two-index conformal windows

International Nuclear Information System (INIS)

Bergner, Georg; Ryttov, Thomas A.; Sannino, Francesco

2015-01-01

Via large and small N c relations we derive nonperturbative results about the conformal window of two-index theories. Using Schwinger-Dyson methods as well as four-loops results we estimate subleading corrections and show that naive large number of colors extrapolations are unreliable when N c is less than about six. Nevertheless useful nonperturbative inequalities for the size of the conformal windows, for any number of colors, can be derived. By further observing that the adjoint conformal window is independent of the number of colors we argue, among other things, that: the large N c two-index conformal window is twice the conformal window of the adjoint representation (which can be determined at small N c ) expressed in terms of Dirac fermions; lattice results for adjoint matter can be used to provide independent information on the conformal dynamics of two-index theories such as SU(N c ) with two and four symmetric Dirac flavors.

Hot Tip: Nominal Exchange Rates and Inflation Indexed Bond Yields

OpenAIRE

Richard H. Clarida

2013-01-01

This paper derives a structural relationship between the nominal exchange rate, national price levels, and observed yields on long maturity inflation - indexed bonds. This relationship can be interpreted as defining the fair value of the exchange rate that will prevail in any model or real world economy in which inflation indexed bonds are traded. An advantage of our derivation is that it does not require restrictive assumptions on financial market equilibrium to be operational. We take our t...

In vivo cell tracking imaging of hexadecyl-4-[{sup 123,} {sup 124}I]iodobenzoate labeled adipose derived stem cells (ADSCs) in rat heart

Energy Technology Data Exchange (ETDEWEB)

Kim, Min Hwan; Lee, Yong Jin; Lee, Kyo Chul [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

2011-10-15

Monitoring of transplanted stem cells for cardiac repair is important part in regenerative medicine. Direct cell labeling techniques using [{sup 18}F]FDG, [{sup 64}Cu]PTSM and [{sup 99m}Tc]-HMPAO have been developed for in vivo imaging. Especially, {sup 18}F-labeled derivates have been widely used for direct labeling agent. But the {sup 18}F has short half life (T{sub 1/2}={approx}2 h), thus this imaging agent has limitation of in vivo imaging. We used {sup 123}I or {sup 124}I which has relative long half life, to track the transplanted stem cells for a long-term imaging. This study is aimed to track the transplanted adipose derived stem cells (ADSCs) in rat heart using hexadecyl-4-[{sup 123,} {sup 124}I]iodobenzoate ([{sup 123,} {sup 124}I]HIB) mediated direct labeling method in vivo

Fully automatic registration and segmentation of first-pass myocardial perfusion MR image sequences.

Science.gov (United States)

Gupta, Vikas; Hendriks, Emile A; Milles, Julien; van der Geest, Rob J; Jerosch-Herold, Michael; Reiber, Johan H C; Lelieveldt, Boudewijn P F

2010-11-01

Derivation of diagnostically relevant parameters from first-pass myocardial perfusion magnetic resonance images involves the tedious and time-consuming manual segmentation of the myocardium in a large number of images. To reduce the manual interaction and expedite the perfusion analysis, we propose an automatic registration and segmentation method for the derivation of perfusion linked parameters. A complete automation was accomplished by first registering misaligned images using a method based on independent component analysis, and then using the registered data to automatically segment the myocardium with active appearance models. We used 18 perfusion studies (100 images per study) for validation in which the automatically obtained (AO) contours were compared with expert drawn contours on the basis of point-to-curve error, Dice index, and relative perfusion upslope in the myocardium. Visual inspection revealed successful segmentation in 15 out of 18 studies. Comparison of the AO contours with expert drawn contours yielded 2.23 ± 0.53 mm and 0.91 ± 0.02 as point-to-curve error and Dice index, respectively. The average difference between manually and automatically obtained relative upslope parameters was found to be statistically insignificant (P = .37). Moreover, the analysis time per slice was reduced from 20 minutes (manual) to 1.5 minutes (automatic). We proposed an automatic method that significantly reduced the time required for analysis of first-pass cardiac magnetic resonance perfusion images. The robustness and accuracy of the proposed method were demonstrated by the high spatial correspondence and statistically insignificant difference in perfusion parameters, when AO contours were compared with expert drawn contours. Copyright © 2010 AUR. Published by Elsevier Inc. All rights reserved.

Information management for high content live cell imaging

Directory of Open Access Journals (Sweden)

White Michael RH

2009-07-01

Full Text Available Abstract Background High content live cell imaging experiments are able to track the cellular localisation of labelled proteins in multiple live cells over a time course. Experiments using high content live cell imaging will generate multiple large datasets that are often stored in an ad-hoc manner. This hinders identification of previously gathered data that may be relevant to current analyses. Whilst solutions exist for managing image data, they are primarily concerned with storage and retrieval of the images themselves and not the data derived from the images. There is therefore a requirement for an information management solution that facilitates the indexing of experimental metadata and results of high content live cell imaging experiments. Results We have designed and implemented a data model and information management solution for the data gathered through high content live cell imaging experiments. Many of the experiments to be stored measure the translocation of fluorescently labelled proteins from cytoplasm to nucleus in individual cells. The functionality of this database has been enhanced by the addition of an algorithm that automatically annotates results of these experiments with the timings of translocations and periods of any oscillatory translocations as they are uploaded to the repository. Testing has shown the algorithm to perform well with a variety of previously unseen data. Conclusion Our repository is a fully functional example of how high throughput imaging data may be effectively indexed and managed to address the requirements of end users. By implementing the automated analysis of experimental results, we have provided a clear impetus for individuals to ensure that their data forms part of that which is stored in the repository. Although focused on imaging, the solution provided is sufficiently generic to be applied to other functional proteomics and genomics experiments. The software is available from: fhttp://code.google.com/p/livecellim/

Surface mineral maps of Afghanistan derived from HyMap imaging spectrometer data, version 2

Science.gov (United States)

Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.

2013-01-01

This report presents a new version of surface mineral maps derived from HyMap imaging spectrometer data collected over Afghanistan in the fall of 2007. This report also describes the processing steps applied to the imaging spectrometer data. The 218 individual flight lines composing the Afghanistan dataset, covering more than 438,000 square kilometers, were georeferenced to a mosaic of orthorectified Landsat images. The HyMap data were converted from radiance to reflectance using a radiative transfer program in combination with ground-calibration sites and a network of cross-cutting calibration flight lines. The U.S. Geological Survey Material Identification and Characterization Algorithm (MICA) was used to generate two thematic maps of surface minerals: a map of iron-bearing minerals and other materials, which have their primary absorption features at the shorter wavelengths of the reflected solar wavelength range, and a map of carbonates, phyllosilicates, sulfates, altered minerals, and other materials, which have their primary absorption features at the longer wavelengths of the reflected solar wavelength range. In contrast to the original version, version 2 of these maps is provided at full resolution of 23-meter pixel size. The thematic maps, MICA summary images, and the material fit and depth images are distributed in digital files linked to this report, in a format readable by remote sensing software and Geographic Information Systems (GIS). The digital files can be downloaded from http://pubs.usgs.gov/ds/787/downloads/.

Surface currents in the Bohai Sea derived from the Korean Geostationary Ocean Color Imager (GOCI)

Science.gov (United States)

Jiang, L.; Wang, M.

2016-02-01

The first geostationary ocean color satellite sensor, the Geostationary Ocean Color Imager (GOCI) onboard the Korean Communication, Ocean, and Meteorological Satellite can monitor and measure ocean phenomena over an area of 2500 × 2500 km2 around the western Pacific region centered at 36°N and 130°E. Hourly measurements during the day around 9:00 to 16:00 local time are a unique capability of GOCI to monitor ocean features of higher temporal variability. In this presentation, we show some recent results of GOCI-derived ocean surface currents in the Bohai Sea using the Maximum Cross-Correlation (MCC) feature tracking method and compare the results with altimetry-inversed tidal current observations produced from Oregon State University (OSU) Tidal Inversion Software (OTIS). The performance of the GOCI-based MCC method is assessed and the discrepancies between the GOCI- and OTIS-derived currents are evaluated. A series of sensitivity studies are conducted with images from various satellite products and of various time differences, MCC adjustable parameters, and influence from other forcings such as wind, to find the best setups for optimal MCC performance. Our results demonstrate that GOCI can effectively provide real-time monitoring of not only water optical, biological, and biogeochemical variability, but also the physical dynamics in the region.

Compuestos volátiles libres y enlazados glicosídicamente en la pulpa de la uva Caimarona (Pourouma cecropiifolia Mart. Compostos voláteis livres e enlaçados glicosídicamente na polpa da uva Caimarona (Pourouma cecropiifolia Mart.

Directory of Open Access Journals (Sweden)

Juliana Constanza Barrios Guio

2010-03-01

Full Text Available Los componentes volátiles presentes en la pulpa de la uva Caimarona se estudiaron mediante GC-MS. Éstos se extrajeron por tres técnicas: evaporación del aroma asistida con solvente (Solvent Assisted Flavour Evaporation SAFE, extracción continua líquido-líquido (LL y destilación por arrastre con vapor-extracción simultanea con solvente orgánico (DES. En general los componentes volátiles predominantes en la pulpa fueron alcoholes alifáticos y terpénicos. Las notas olfativas del extracto SAFE fueron descritas como floral tenue y verde herbal similares a las exhibidas por la pulpa fresca. Este extracto presentó como componentes mayoritarios linalol 1,2-propanodiol y salicilato de metilo. En contraste, el extracto LL presentó notas que recuerdan la uva pasa y el vino moscatel y sus componentes mayoritarios fueron el ácido acético, el salicilato de metilo y el 2,6-dimetil-2(Z,7-octadien-1,6-diol. El extracto DES fue descrito con notas fresca, floral, cereal y amargo y está constituido por un reducido número de componentes mostrando el efecto negativo de la temperatura en la extracción; sus componentes mayoritarios fueron 1,2-propanodiol, linalol y salicilato de metilo. Adicionalmente, los componentes volátiles mayoritarios liberados por hidrólisis enzimática (Rohapect D5L de los glicósidos de la pulpa fueron ácido acético, ácido benzoico y vainillina. Cabe destacar que aunque el linalol no se encontró entre las agliconas volátiles, se detectaron los dioles biogenéticamente relacionados: 3,7-dimetil-1,5-octadien-3,7-diol y los isómeros E y Z del 2,6-dimetil-2,7-octadien-1,6-diol.Os componentes voláteis presentes na polpa da uva Caimarona foram estudados mediante GC-MS. Estes foram extraídos por três técnicas: evaporação de aroma assistida com solvente (Solvent Assisted Flavour Evaporation SAFE, extração continua líquido-líquido (LL e destilação por arraste com vapor-extração simultânea com solvente org

SU-C-BRA-07: Variability of Patient-Specific Motion Models Derived Using Different Deformable Image Registration Algorithms for Lung Cancer Stereotactic Body Radiotherapy (SBRT) Patients

Energy Technology Data Exchange (ETDEWEB)

Dhou, S; Williams, C [Brigham and Women’s Hospital / Harvard Medical School, Boston, MA (United States); Ionascu, D [William Beaumont Hospital, Royal Oak, MI (United States); Lewis, J [University of California at Los Angeles, Los Angeles, CA (United States)

2016-06-15

Purpose: To study the variability of patient-specific motion models derived from 4-dimensional CT (4DCT) images using different deformable image registration (DIR) algorithms for lung cancer stereotactic body radiotherapy (SBRT) patients. Methods: Motion models are derived by 1) applying DIR between each 4DCT image and a reference image, resulting in a set of displacement vector fields (DVFs), and 2) performing principal component analysis (PCA) on the DVFs, resulting in a motion model (a set of eigenvectors capturing the variations in the DVFs). Three DIR algorithms were used: 1) Demons, 2) Horn-Schunck, and 3) iterative optical flow. The motion models derived were compared using patient 4DCT scans. Results: Motion models were derived and the variations were evaluated according to three criteria: 1) the average root mean square (RMS) difference which measures the absolute difference between the components of the eigenvectors, 2) the dot product between the eigenvectors which measures the angular difference between the eigenvectors in space, and 3) the Euclidean Model Norm (EMN), which is calculated by summing the dot products of an eigenvector with the first three eigenvectors from the reference motion model in quadrature. EMN measures how well an eigenvector can be reconstructed using another motion model derived using a different DIR algorithm. Results showed that comparing to a reference motion model (derived using the Demons algorithm), the eigenvectors of the motion model derived using the iterative optical flow algorithm has smaller RMS, larger dot product, and larger EMN values than those of the motion model derived using Horn-Schunck algorithm. Conclusion: The study showed that motion models vary depending on which DIR algorithms were used to derive them. The choice of a DIR algorithm may affect the accuracy of the resulting model, and it is important to assess the suitability of the algorithm chosen for a particular application. This project was supported

SU-C-BRA-07: Variability of Patient-Specific Motion Models Derived Using Different Deformable Image Registration Algorithms for Lung Cancer Stereotactic Body Radiotherapy (SBRT) Patients

International Nuclear Information System (INIS)

Dhou, S; Williams, C; Ionascu, D; Lewis, J

2016-01-01

Purpose: To study the variability of patient-specific motion models derived from 4-dimensional CT (4DCT) images using different deformable image registration (DIR) algorithms for lung cancer stereotactic body radiotherapy (SBRT) patients. Methods: Motion models are derived by 1) applying DIR between each 4DCT image and a reference image, resulting in a set of displacement vector fields (DVFs), and 2) performing principal component analysis (PCA) on the DVFs, resulting in a motion model (a set of eigenvectors capturing the variations in the DVFs). Three DIR algorithms were used: 1) Demons, 2) Horn-Schunck, and 3) iterative optical flow. The motion models derived were compared using patient 4DCT scans. Results: Motion models were derived and the variations were evaluated according to three criteria: 1) the average root mean square (RMS) difference which measures the absolute difference between the components of the eigenvectors, 2) the dot product between the eigenvectors which measures the angular difference between the eigenvectors in space, and 3) the Euclidean Model Norm (EMN), which is calculated by summing the dot products of an eigenvector with the first three eigenvectors from the reference motion model in quadrature. EMN measures how well an eigenvector can be reconstructed using another motion model derived using a different DIR algorithm. Results showed that comparing to a reference motion model (derived using the Demons algorithm), the eigenvectors of the motion model derived using the iterative optical flow algorithm has smaller RMS, larger dot product, and larger EMN values than those of the motion model derived using Horn-Schunck algorithm. Conclusion: The study showed that motion models vary depending on which DIR algorithms were used to derive them. The choice of a DIR algorithm may affect the accuracy of the resulting model, and it is important to assess the suitability of the algorithm chosen for a particular application. This project was supported

Combined Use of Multi-Temporal Optical and Radar Satellite Images for Grassland Monitoring

Directory of Open Access Journals (Sweden)

Pauline Dusseux

2014-06-01

Full Text Available The aim of this study was to assess the ability of optical images, SAR (Synthetic Aperture Radar images and the combination of both types of data to discriminate between grasslands and crops in agricultural areas where cloud cover is very high most of the time, which restricts the use of visible and near-infrared satellite data. We compared the performances of variables extracted from four optical and five SAR satellite images with high/very high spatial resolutions acquired during the growing season. A vegetation index, namely the NDVI (Normalized Difference Vegetation Index, and two biophysical variables, the LAI (Leaf Area Index and the fCOVER (fraction of Vegetation Cover were computed using optical time series and polarization (HH, VV, HV, VH. The polarization ratio and polarimetric decomposition (Freeman–Durden and Cloude–Pottier were calculated using SAR time series. Then, variables derived from optical, SAR and both types of remotely-sensed data were successively classified using the Support Vector Machine (SVM technique. The results show that the classification accuracy of SAR variables is higher than those using optical data (0.98 compared to 0.81. They also highlight that the combination of optical and SAR time series data is of prime interest to discriminate grasslands from crops, allowing an improved classification accuracy.

A North American regional reanalysis climatology of the Haines Index

Science.gov (United States)

Wei Lu; Joseph J. (Jay) Charney; Sharon Zhong; Xindi Bian; Shuhua. Liu

2011-01-01

A warm-season (May through October) Haines Index climatology is derived using 32-km regional reanalysis temperature and humidity data from 1980 to 2007. We compute lapse rates, dewpoint depressions, Haines Index factors A and B, and values for each of the low-, mid- and high-elevation variants of the Haines Index. Statistical techniques are used to investigate the...

Prediction of quantitative intrathoracic fluid volume to diagnose pulmonary oedema using LabVIEW.

Science.gov (United States)

Urooj, Shabana; Khan, M; Ansari, A Q; Lay-Ekuakille, Aimé; Salhan, Ashok K

2012-01-01

Pulmonary oedema is a life-threatening disease that requires special attention in the area of research and clinical diagnosis. Computer-based techniques are rarely used to quantify the intrathoracic fluid volume (IFV) for diagnostic purposes. This paper discusses a software program developed to detect and diagnose pulmonary oedema using LabVIEW. The software runs on anthropometric dimensions and physiological parameters, mainly transthoracic electrical impedance (TEI). This technique is accurate and faster than existing manual techniques. The LabVIEW software was used to compute the parameters required to quantify IFV. An equation relating per cent control and IFV was obtained. The results of predicted TEI and measured TEI were compared with previously reported data to validate the developed program. It was found that the predicted values of TEI obtained from the computer-based technique were much closer to the measured values of TEI. Six new subjects were enrolled to measure and predict transthoracic impedance and hence to quantify IFV. A similar difference was also observed in the measured and predicted values of TEI for the new subjects.

The Role of Trait Emotional Intelligence in Academic Performance: Theoretical Overview and Empirical Update.

Science.gov (United States)

Perera, Harsha N

2016-01-01

Considerable debate still exists among scholars over the role of trait emotional intelligence (TEI) in academic performance. The dominant theoretical position is that TEI should be orthogonal or only weakly related to achievement; yet, there are strong theoretical reasons to believe that TEI plays a key role in performance. The purpose of the current article is to provide (a) an overview of the possible theoretical mechanisms linking TEI with achievement and (b) an update on empirical research examining this relationship. To elucidate these theoretical mechanisms, the overview draws on multiple theories of emotion and regulation, including TEI theory, social-functional accounts of emotion, and expectancy-value and psychobiological model of emotion and regulation. Although these theoretical accounts variously emphasize different variables as focal constructs, when taken together, they provide a comprehensive picture of the possible mechanisms linking TEI with achievement. In this regard, the article redresses the problem of vaguely specified theoretical links currently hampering progress in the field. The article closes with a consideration of directions for future research.

Landmark Detection in Orbital Images Using Salience Histograms

Science.gov (United States)

Wagstaff, Kiri L.; Panetta, Julian; Schorghofer, Norbert; Greeley, Ronald; PendletonHoffer, Mary; bunte, Melissa

2010-01-01

NASA's planetary missions have collected, and continue to collect, massive volumes of orbital imagery. The volume is such that it is difficult to manually review all of the data and determine its significance. As a result, images are indexed and searchable by location and date but generally not by their content. A new automated method analyzes images and identifies "landmarks," or visually salient features such as gullies, craters, dust devil tracks, and the like. This technique uses a statistical measure of salience derived from information theory, so it is not associated with any specific landmark type. It identifies regions that are unusual or that stand out from their surroundings, so the resulting landmarks are context-sensitive areas that can be used to recognize the same area when it is encountered again. A machine learning classifier is used to identify the type of each discovered landmark. Using a specified window size, an intensity histogram is computed for each such window within the larger image (sliding the window across the image). Next, a salience map is computed that specifies, for each pixel, the salience of the window centered at that pixel. The salience map is thresholded to identify landmark contours (polygons) using the upper quartile of salience values. Descriptive attributes are extracted for each landmark polygon: size, perimeter, mean intensity, standard deviation of intensity, and shape features derived from an ellipse fit.

Folic acid derivatives for PET imaging and therapy addressing folate receptor positive tumors

Energy Technology Data Exchange (ETDEWEB)

Schieferstein, Hanno

2013-07-01

Folic acid, also known as vitamin B9, is the oxidized form of 5,6,7,8-tetrahydrofolate, which serves as methyl- or methylene donor (C1-building blocks) during DNA synthesis. Under physiological conditions the required amount of 5,6,7,8-tetrahydrofolate for survival of the cell is accomplished through the reduced folate carrier (RFC). In contrast, the supply of 5,6,7,8-tetrahydrofolate is insufficient under pathophysiological conditions of tumors due to an increased proliferation rate. Consequently, many tumor cells exhibit an (over)expression of the folate receptor. This phenomenon has been applied to diagnostics (PET, SPECT, MR) to image FR-positive tumors and on the other hand to treat malignancies related to a FR (over)expression. Based on this concept, a new {sup 18}F-labeled folate for PET imaging has been developed and was evaluated in vivo using tumor-bearing mice. The incorporation of oligoethylene spacers into the molecular structure led to a significant enhancement of the pharmacokinetics in comparison to previously developed {sup 18}F-folates. The liver uptake could be reduced by one sixth by remaining a tumor uptake of 3%ID/g leading to better contrast ratios. Encouraged by these results, a clickable {sup 18}F-labeled serine-based prosthetic group has been synthesized, again with the idea to improve the metabolic and pharmacokinetic profile of hydrophilic radiotracers. Therefore, an alkyne-carrying azido-functionalized serine derivative for coupling to biomolecules was synthesized and a chlorine leaving group for {sup 18}F-labeling, which could be accomplished using a microwave-assisted synthesis, a [K is contained in 2.2.2]{sup +}/carbonate system in DMSO. Radiochemical yields of 77±6% could be achieved. The promising results obtained from the FR-targeting concept in the diagnostic field have been transferred to the boron neutron capture therapy. Therefore, a folate derivative was coupled to different boron clusters and cell uptake studies were

Folic acid derivatives for PET imaging and therapy addressing folate receptor positive tumors

International Nuclear Information System (INIS)

Schieferstein, Hanno

2013-01-01

Folic acid, also known as vitamin B9, is the oxidized form of 5,6,7,8-tetrahydrofolate, which serves as methyl- or methylene donor (C1-building blocks) during DNA synthesis. Under physiological conditions the required amount of 5,6,7,8-tetrahydrofolate for survival of the cell is accomplished through the reduced folate carrier (RFC). In contrast, the supply of 5,6,7,8-tetrahydrofolate is insufficient under pathophysiological conditions of tumors due to an increased proliferation rate. Consequently, many tumor cells exhibit an (over)expression of the folate receptor. This phenomenon has been applied to diagnostics (PET, SPECT, MR) to image FR-positive tumors and on the other hand to treat malignancies related to a FR (over)expression. Based on this concept, a new 18 F-labeled folate for PET imaging has been developed and was evaluated in vivo using tumor-bearing mice. The incorporation of oligoethylene spacers into the molecular structure led to a significant enhancement of the pharmacokinetics in comparison to previously developed 18 F-folates. The liver uptake could be reduced by one sixth by remaining a tumor uptake of 3%ID/g leading to better contrast ratios. Encouraged by these results, a clickable 18 F-labeled serine-based prosthetic group has been synthesized, again with the idea to improve the metabolic and pharmacokinetic profile of hydrophilic radiotracers. Therefore, an alkyne-carrying azido-functionalized serine derivative for coupling to biomolecules was synthesized and a chlorine leaving group for 18 F-labeling, which could be accomplished using a microwave-assisted synthesis, a [K is contained in 2.2.2] + /carbonate system in DMSO. Radiochemical yields of 77±6% could be achieved. The promising results obtained from the FR-targeting concept in the diagnostic field have been transferred to the boron neutron capture therapy. Therefore, a folate derivative was coupled to different boron clusters and cell uptake studies were conducted. The synthesis of

Imaging sciences workshop

Energy Technology Data Exchange (ETDEWEB)

Candy, J.V.

1994-11-15

This workshop on the Imaging Sciences sponsored by Lawrence Livermore National Laboratory contains short abstracts/articles submitted by speakers. The topic areas covered include the following: Astronomical Imaging; biomedical imaging; vision/image display; imaging hardware; imaging software; Acoustic/oceanic imaging; microwave/acoustic imaging; computed tomography; physical imaging; imaging algorithms. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

Contrast-enhanced magnetic resonance imaging of the breast: the value of pharmacokinetic parameters derived from fast dynamic imaging during initial enhancement in classifying lesions

International Nuclear Information System (INIS)

Veltman, J.; Stoutjesdijk, M.; Mann, R.; Huisman, H.J.; Barentsz, J.O.; Blickman, J.G.; Boetes, C.

2008-01-01

The value of pharmacokinetic parameters derived from fast dynamic imaging during initial enhancement in characterizing breast lesions on magnetic resonance imaging (MRI) was evaluated. Sixty-eight malignant and 34 benign lesions were included. In the scanning protocol, high temporal resolution imaging was combined with high spatial resolution imaging. The high temporal resolution images were recorded every 4.1 s during initial enhancement (fast dynamic analysis). The high spatial resolution images were recorded at a temporal resolution of 86 s (slow dynamic analysis). In the fast dynamic evaluation pharmacokinetic parameters (K trans , V e and k ep ) were evaluated. In the slow dynamic analysis, each lesion was scored according to the BI-RADS classification. Two readers evaluated all data prospectively. ROC and multivariate analysis were performed. The slow dynamic analysis resulted in an AUC of 0.85 and 0.83, respectively. The fast dynamic analysis resulted in an AUC of 0.83 in both readers. The combination of both the slow and fast dynamic analyses resulted in a significant improvement of diagnostic performance with an AUC of 0.93 and 0.90 (P = 0.02). The increased diagnostic performance found when combining both methods demonstrates the additional value of our method in further improving the diagnostic performance of breast MRI. (orig.)

Estimation of an image derived input function with MR-defined carotid arteries in FDG-PET human studies using a novel partial volume correction method

DEFF Research Database (Denmark)

Sari, Hasan; Erlandsson, Kjell; Law, Ian

2017-01-01

Kinetic analysis of18F-fluorodeoxyglucose positron emission tomography data requires an accurate knowledge the arterial input function. The gold standard method to measure the arterial input function requires collection of arterial blood samples and is an invasive method. Measuring an image deriv...... input function (p > 0.12 for grey matter and white matter). Hence, the presented image derived input function extraction method can be a practical alternative to noninvasively analyze dynamic18F-fluorodeoxyglucose data without the need for blood sampling....

Grafting polyethylenimine with quinoline derivatives for targeted imaging of intracellular Zn{sup 2+} and logic gate operations

Energy Technology Data Exchange (ETDEWEB)

Pan, Yi; Shi, Yupeng; Chen, Junying; Wong, Chap-Mo; Zhang, Heng [Key Laboratory of Sensing Technology and Biomedical Instruments (Guangdong Province), School of Engineering, Sun Yat-Sen University, Guangzhou (China); Li, Mei-Jin [Key Laboratory of Analysis and Detection Technology for Food Safety, Ministry of Education and Fujian Province, Department of Chemistry, Fuzhou University, Fuzhou (China); Li, Cheuk-Wing [Institute of Chinese Medical Sciences, University of Macau (China); Yi, Changqing, E-mail: yichq@mail.sysu.edu.cn [Key Laboratory of Sensing Technology and Biomedical Instruments (Guangdong Province), School of Engineering, Sun Yat-Sen University, Guangzhou (China); Research Institute of Sun Yat-Sen University in Shenzhen, Shenzhen (China)

2016-12-01

In this study, a highly sensitive and selective fluorescent Zn{sup 2+} probe which exhibited excellent biocompatibility, water solubility, and cell-membrane permeability, was facilely synthesized in a single step by grafting polyethyleneimine (PEI) with quinoline derivatives. The primary amino groups in the branched PEI can increase water solubility and cell permeability of the probe PEIQ, while quinoline derivatives can specifically recognize Zn{sup 2+} and reduce the potential cytotoxicity of PEI. Basing on fluorescence off-on mechanism, PEIQ demonstrated excellent sensing capability towards Zn{sup 2+} in absolute aqueous solution, where a high sensitivity with a detection limit as low as 38.1 nM, and a high selectivity over competing metal ions and potential interfering amino acids, were achieved. Inspired by these results, elementary logic operations (YES, NOT and INHIBIT) have been constructed by employing PEIQ as the gate while Zn{sup 2+} and EDTA as chemical inputs. Together with the low cytotoxicity and good cell-permeability, the practical application of PEIQ in living cell imaging was satisfactorily demonstrated, emphasizing its wide application in fundamental biology research. - Graphical abstract: The fluorescent Zn{sup 2+} probe, PEIQ, is facilely synthesized by grafting PEI with 8-CAAQ, and demonstrated for the pratical applications in Zn{sup 2+} imaging and implementation of molecular logic operations within biological cells. - Highlights: • PEIQ, fluorescent Zn{sup 2+} probe, is synthesized by grafting PEI with quinoline derivatives. • PEIQ exhibits high sensitivity and selectivity in absolute aqueous solution. • PEIQ is biocompatible, water soluble, and cell-membrane permeable. • Elementary logic operations have been demonstrated for PEIQ/Zn{sup 2+}/EDTA system. • The practical application of PEIQ in living cell imaging is demonstrated.

Empirical temperature dependence of the refractive index of semiconductors

NARCIS (Netherlands)

Herve, P.J.L.; Vandamme, L.K.J.

1995-01-01

Values of the temperature coefficient of the refractive index were obtained from the derivation of a simple relation between energy band-gap and refractive index in semiconductors. These values, (dn/dT)/n, were compared to the experimental data found in literature. Our model, with only one fitting

Ultraviolet light induced refractive index structures in germanosilica

DEFF Research Database (Denmark)

Svalgaard, Mikael

1997-01-01

The focus of the research presented in this ph.d. thesis is refractive index structures photoinduced in germanonsilica waveguides with ultra-violet (UV) radiation. The physical mechanisms involved in photosensitivity and applications of a wide range of UV induced refractive index structures in both...... application of a scanning near-field optical microscope to obtain high resolution images of UV induced refractive index structures and by monitoring the dynamics of UV induced index changes and luminescence. During part of my ph.d. project I have worked at the National Institute of Standards and Technolgy...

Climate Prediction Center (CPC) Monthly Pacific North American Teleconnection Pattern Index

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Monthly tabulated index of the Pacific/ North American teleconnection pattern. The data spans the period 1950 to present. The index is derived from a rotated...

Climate Prediction Center (CPC) Monthly North Atlantic Oscillation (NAO) teleconnection index

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Monthly tabulated index of the North Atlantic Oscillation (NAO) teleconnection pattern. The data spans the period 1950 to present. The index is derived from a...

A comparison of footprint indexes calculated from ink and electronic footprints.

Science.gov (United States)

Urry, S R; Wearing, S C

2001-04-01

Pressure platforms offer the potential to measure and record electronic footprints rapidly; however, the accuracy of geometric indexes derived from these prints has not been investigated. A comparison of conventional ink footprints with simultaneously acquired electronic prints revealed significant differences in several geometric indexes. The contact area was consistently underestimated by the electronic prints and resulted in a significant change in the arch index. The long plantar angle was poorly correlated between techniques. This study demonstrated that electronic footprints, derived from a pressure platform, are not representative of the equivalent ink footprints and, consequently, should not be interpreted with reference to literature on conventional footprints.

Evaluating scintillators used in radiation detectors of medical imaging systems by the effective fidelity index method

International Nuclear Information System (INIS)

Kandarakis, I.; Cavouras, D.; Prassopoulos, P.; Kanellopoulos, E.; Nomicos, C.D.; Panayiotakis, G.S.

1999-01-01

Objective: The performance of medical X-ray image receptors depends: (1) on the scintillator light emission efficiency; and (2) on the compatibility of the scintillator light spectrum with the spectral sensitivity of the light detector (film, photocathode, or photodiode), employed in conjunction with the scintillator. In this study, a scintillator performance measure, the effective fidelity index (EFI), is defined as function of both the scintillator light emission efficiency and spectral compatibility. Materials and Method: CsI:Na, Gd 2 O 2 S:Tb and La 2 O 2 S:Tb scintillators were employed in the form of phosphor screens prepared in our laboratory with various coating thicknesses. The screens were irradiated with X-rays employing tube voltages ranging between 50-120 kVp. Results: The EFI performance of CsI:Na was found to increase with screen coating thickness and it was best when combined with the orthochromatic film or the ES/20 photocathode. Gd 2 O 2 S:Tb showed peak EFI performance at 70 mg/cm 2 coating thickness and it was well combined with the light detectors considered. Conclusion: In accordance with our results, CsI:Na may be employed in radiography when adequately protected against humidity. Gd 2 O 2 S:Tb suitability for conventional imaging was verified and it was found that it may be useful in all types of digital imaging. La 2 O 2 S:Tb could also be used in digital detectors of imaging applications demanding medium X-ray tube voltages

Near-infrared-fluorescence imaging of lymph nodes by using liposomally formulated indocyanine green derivatives.

Science.gov (United States)

Toyota, Taro; Fujito, Hiromichi; Suganami, Akiko; Ouchi, Tomoki; Ooishi, Aki; Aoki, Akira; Onoue, Kazutaka; Muraki, Yutaka; Madono, Tomoyuki; Fujinami, Masanori; Tamura, Yutaka; Hayashi, Hideki

2014-01-15

Liposomally formulated indocyanine green (LP-ICG) has drawn much attention as a highly sensitive near-infrared (NIR)-fluorescence probe for tumors or lymph nodes in vivo. We synthesized ICG derivatives tagged with alkyl chains (ICG-Cn), and we examined NIR-fluorescence imaging for lymph nodes in the lower extremities of mice by using liposomally formulated ICG-Cn (LP-ICG-Cn) as well as conventional liposomally formulated ICG (LP-ICG) and ICG. Analysis with a noninvasive preclinical NIR-fluorescence imaging system revealed that LP-ICG-Cn accumulates in only the popliteal lymph node 1h after injection into the footpad, whereas LP-ICG and ICG accumulate in the popliteal lymph node and other organs like the liver. This result indicates that LP-ICG-Cn is a useful NIR-fluorescence probe for noninvasive in vivo bioimaging, especially for the sentinel lymph node. Copyright © 2013 Elsevier Ltd. All rights reserved.

Multi-scale structural similarity index for motion detection

Directory of Open Access Journals (Sweden)

M. Abdel-Salam Nasr

2017-07-01

Full Text Available The most recent approach for measuring the image quality is the structural similarity index (SSI. This paper presents a novel algorithm based on the multi-scale structural similarity index for motion detection (MS-SSIM in videos. The MS-SSIM approach is based on modeling of image luminance, contrast and structure at multiple scales. The MS-SSIM has resulted in much better performance than the single scale SSI approach but at the cost of relatively lower processing speed. The major advantages of the presented algorithm are both: the higher detection accuracy and the quasi real-time processing speed.

Historic Low Wall Detection via Topographic Parameter Images Derived from Fine-Resolution DEM

Directory of Open Access Journals (Sweden)

Hone-Jay Chu

2017-11-01

Full Text Available Coral walls protect vegetation gardens from strong winds that sweep across Xiji Island, Taiwan Strait for half the year. Topographic parameters based on light detection and ranging (LiDAR-based high-resolution digital elevation model (DEM provide obvious correspondence with the expected form of landscape features. The information on slope, curvature, and openness can help identify the location of landscape features. This study applied the automatic landscape line detection to extract historic vegetable garden wall lines from a LiDAR-derived DEM. The three rapid processes used in this study included the derivation of topographic parameters, line extraction, and aggregation. The rules were extracted from a decision tree to check the line detection from multiple topographic parameters. Results show that wall line detection with multiple topographic parameter images is an alternative means of obtaining essential historic wall feature information. Multiple topographic parameters are highly related to low wall feature identification. Furthermore, the accuracy of wall feature detection is 74% compared with manual interpretation. Thus, this study provides rapid wall detection systems with multiple topographic parameters for further historic landscape management.

Hierarchy of Electronic Properties of Chemically Derived and Pristine Graphene Probed by Microwave Imaging

KAUST Repository

Kundhikanjana, Worasom

2009-11-11

Local electrical imaging using microwave impedance microscope is performed on graphene in different modalities, yielding a rich hierarchy of the local conductivity. The low-conductivity graphite oxide and its derivatives show significant electronic inhomogeneity. For the conductive chemical graphene, the residual defects lead to a systematic reduction of the microwave signals. In contrast, the signals on pristine graphene agree well with a lumped-element circuit model. The local impedance information can also be used to verify the electrical contact between overlapped graphene pieces. © 2009 American Chemical Society.

Climate Prediction Center (CPC) East Atlantic/ Western Russia Teleconnection Pattern Index

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Monthly tabulated index of the East Atlantic/ Western Russia teleconnection pattern. The data spans the period 1950 to present. The index is derived from a rotated...

Climate Prediction Center (CPC) East Pacific/ North Pacific Teleconnection Pattern Index

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Monthly tabulated index of the East Pacific/ North Pacific teleconnection pattern. The data spans the period 1950 to present. The index is derived from a rotated...

Dose reduction in coronary artery imaging with 64-row multi-slice helical CT with body mass index-dependent mA selection

International Nuclear Information System (INIS)

Gao Jianhua; Wang Guisheng; Zheng Jingchen; Li Jianying; Sun Xianchang; Gao Caihong; Dai Ruping

2008-01-01

Objective: To evaluate the robustness of body mass index (BMI) adapted tube current selection method for obtaining consistent image quality in MSCT coronary artery imaging. Methods: Initially one hundred patients in the control group (C group) underwent cardiac scans using GE 64-row VCT with standard scan protocol (640 mA, 120 kV, 0.35 sec, body bowtie, C 2 filter). Noise measurement was obtained for each patient using the average of three consecutive slices in the ascending aorta with ROI of 10 mm x 10 mm to establish the relationship between BMI, desired image noise (IN) and required mA. An excel table was established to predict the required mA to achieve a desired IN for each patient with different BMI. A second group of one hundred cardiac patients (L group) was scanned with BMI-adapted mA from the table to evaluate the practicability of this method. BMI, IN, CT dose index (CTDI), effective dose (ED) were all recorded. Results: For the control group of 100 patients, the mean values and standard deviations of image quality score (IQS), BMI, IN and ED were 3.71±0.54, 25.08±2.63, 24.56±5.03 and (17.63±1.68) mSv (with range of 15-22 mSv). Regression analysis indicated linear relationship between BMI and image noise with fixed mA. Using the relationship between tube current and image noise and noise ratio between large bowtie and cardiac bowtie, the following equation for the required tube current Xma to achieve present image noise of INa for patient with certain BMI value when using cardiac bowtie could be then obtained: Xma=Fma x [(k 1 x BMI + c 1 )/Ina] 2 , where Fma=640 mA, k 1 =1.033, c 1 = -3.2, INa=27 in the study. (2) For the patients in L group, the mean values and standard deviations of IQS, BMI, and IN were 3.69±0.53, 25.07±2.91, and 26.61±3.44, respectively. The average tube current used was (469.95±113.45) mA, depending on patient's BMI values. The average effectively dose was (9.08±2.25) mSv. There was no statistically difference between the

Value of three-dimensional volume rendering images in the assessment of the centrality index for preoperative planning in patients with renal masses.

Science.gov (United States)

Sofia, C; Magno, C; Silipigni, S; Cantisani, V; Mucciardi, G; Sottile, F; Inferrera, A; Mazziotti, S; Ascenti, G

2017-01-01

To evaluate the precision of the centrality index (CI) measurement on three-dimensional (3D) volume rendering technique (VRT) images in patients with renal masses, compared to its standard measurement on axial images. Sixty-five patients with renal lesions underwent contrast-enhanced multidetector (MD) computed tomography (CT) for preoperative imaging. Two readers calculated the CI on two-dimensional axial images and on VRT images, measuring it in the plane that the tumour and centre of the kidney were lying in. Correlation and agreement of interobserver measurements and inter-method results were calculated using intraclass correlation (ICC) coefficients and the Bland-Altman method. Time saving was also calculated. The correlation coefficients were r=0.99 (ppresent study showed that VRT and axial images produce almost identical values of CI, with the advantages of greater ease of execution and a time saving of almost 50% for 3D VRT images. In addition, VRT provides an integrated perspective that can better assist surgeons in clinical decision making and in operative planning, suggesting this technique as a possible standard method for CI measurement. Copyright © 2016 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

Integrated study of biomass index in La Herreria (Sierra de Guadarrama)

Science.gov (United States)

Hernandez Díaz-Ambrona, Carlos G.

2016-04-01

Drought severity has many implications for society, including its impacts on the water supply, water pollution, reservoir management and ecosystem. There have been many attempts to characterize its severity, resulting in the numerous drought indices that have been developed (Niemeyer 2008). The'biomass index', based on satellite image derived Normalized Difference Vegetation Index (NDVI) has been used in several countries for pasture and forage crops for some years (Rao, 2010; Escribano-Rodriguez et al., 2014). NDVI generally provides a broad overview of the vegetation condition and spatial vegetation distribution in a region. Vegetative drought is closely related with weather impacts. However, in NDVI, the weather component gets subdued by the strong ecological component. Another vegetation index is Vegetation Condition Index (VCI) that separates the short-term weather-related NDVI fluctuations from the long-term ecosystem changes (Kogan, 1990). Therefore, while NDVI shows seasonal vegetation dynamics, VCI rescales vegetation dynamics between 0 and 100 to reflect relative changes in the vegetation condition from extremely bad to optimal (Kogan et al., 2003). In this work a pasture area at La Herreria (Sierra de Guadarrama, Spain) has been delimited. Then, NDVI historical data are reconstructed based on remote sensing imaging MODIS, with 500x500m2 resolution. From the closest meteorological station (Santolaria-Canales, 2015) records of weekly precipitation, temperature and evapotranspiration from 2001 till 2012 were obtained. Standard Precipitation Index (SPI), Crop Moisture Index (CMI) (Palmer, 1968) and Evapotranspiration-Precipitation Ratio (EPR) are calculated in an attempt to relate them to several vegetation indexes: NDVI, VCI and NDVI Change Ratio to Median (RMNDVI). The results are discussed in the context of pasture index insurance. References Escribano Rodriguez, J.Agustín, Carlos Gregorio Hernández Díaz-Ambrona and Ana María Tarquis Alfonso

In vivo bioluminescence imaging using orthotopic xenografts towards patient's derived-xenograft Medulloblastoma models.

Science.gov (United States)

Asadzadeh, Fatemeh; Ferrucci, Veronica; DE Antonellis, Pasqualino; Zollo, Massimo

2017-03-01

Medulloblastoma is a cerebellar neoplasia of the central nervous system. Four molecular subgrups have been identified (MBWNT, MBSHH, MBgroup3 and MBgroup4) with distinct genetics and clinical outcome. Among these, MBgroup3-4 are highly metastatic with the worst prognosis. The current standard therapy includes surgery, radiation and chemotherapy. Thus, specific treatments adapted to cure those different molecular subgroups are needed. The use of orthotopic xenograft models, together with the non-invasive in vivo biolumiscence imaging (BLI) technology, is emerging during preclinical studies to test novel therapeutics for medulloblastoma treatment. Orthotopic MB xenografts were performed by injection of Daoy-luc cells, that had been previously infected with lentiviral particles to stably express luciferase gene, into the fourth right ventricle of the cerebellum of ten nude mice. For the implantation, specific stereotactic coordinates were used. Seven days after the implantation the mice were imaged by acquisitions of bioluminescence imaging (BLI) using IVIS 3D Illumina Imaging System (Xenogen). Tumor growth was evaluated by quantifying the bioluminescence signals using the integrated fluxes of photons within each area of interest using the Living Images Software Package 3.2 (Xenogen-Perkin Elmer). Finally, histological analysis using hematoxylin-eosin staining was performed to confirm the presence of tumorigenic cells into the cerebellum of the mice. We describe a method to use the in vivo bioluminescent imaging (BLI) showing the potential to be used to investigate the potential antitumorigenic effects of a drug for in vivo medulloblastoma treatment. We also discuss other studies in which this technology has been applied to obtain a more comprehensive knowledge of medulloblastoma using orthotopic xenograft mouse models. There is a need to develop patient's derived-xenograft (PDX) model systems to test novel drugs for medulloblastoma treatment within each molecular sub

Quantitative mapping of hepatic perfusion index using MR imaging: a potential reproducible tool for assessing tumour response to treatment with the antiangiogenic compound BIBF 1120, a potent triple angiokinase inhibitor

International Nuclear Information System (INIS)

Miyazaki, Keiko; Collins, David J.; Walker-Samuel, Simon; Leach, Martin O.; Koh, Dow-Mu; Taylor, Jane N.; Padhani, Anwar R.

2008-01-01

Hepatic metastases are arterially supplied, resulting in an elevated hepatic perfusion index (HPI). The purpose of this study was to use dynamic contrast-enhanced (DCE) MR imaging to quantify the HPI of metastases and the liver before and after treatment with a novel antiangiogenic drug. Ten patients with known metastatic liver disease underwent DCE-MR studies. HPIs of metastases and whole liver were derived using regions of interest (ROIs) and calculated on a pixel-by-pixel basis from quantified changes in gadopentetate dimeglumine (Gd-DTPA) concentration. The HPI measurement error prior to treatment was derived by the Bland-Altman analysis. The median HPI before and after treatment with antiangiogenic drug BIBF 1120 were compared using the Wilcoxon signed rank test. Prior to treatment, the median HPI of metastases, 0.75 ± 0.14, was significantly higher than that of the whole liver, 0.66 ± 0.16 (p < 0.01). Bland-Altman reproducibility coefficients of the median HPI from metastases and whole liver were 13.0 and 5.1% respectively. The median HPI of metastases decreased significantly at 28 days after treatment with BIBF 1120 (p < 0.05). This pilot study demonstrates that HPI determined using quantified Gd-DTPA concentration is reproducible and may be useful for monitoring antiangiogenic treatment response of hepatic metastases. (orig.)

Effect of chirality on cellular uptake, imaging and photodynamic therapy of photosensitizers derived from chlorophyll-a.

Science.gov (United States)

Srivatsan, Avinash; Pera, Paula; Joshi, Penny; Wang, Yanfang; Missert, Joseph R; Tracy, Erin C; Tabaczynski, Walter A; Yao, Rutao; Sajjad, Munawwar; Baumann, Heinz; Pandey, Ravindra K

2015-07-01

We have previously shown that the (124)I-analog of methyl 3-(1'-m-iodobenzyloxy) ethyl-3-devinyl-pyropheophorbide-a derived as racemic mixture from chlorophyll-a can be used for PET (positron emission tomography)-imaging in animal tumor models. On the other hand, as a non-radioactive analog, it showed excellent fluorescence and photodynamic therapy (PDT) efficacy. Thus, a single agent in a mixture of radioactive ((124)I-) and non-radioactive ((127)I) material can be used for both dual-imaging and PDT of cancer. Before advancing to Phase I human clinical trials, we evaluated the activity of the individual isomers as well as the impact of a chiral center at position-3(1) in directing in vitro/in vivo cellular uptake, intracellular localization, epithelial tumor cell-specific retention, fluorescence/PET imaging, and photosensitizing ability. The results indicate that both isomers (racemates), either as methyl ester or carboxylic acid, were equally effective. However, the methyl ester analogs, due to subcellular deposition into vesicular structures, were preferentially retained. All derivatives containing carboxylic acid at the position-17(2) were noted to be substrate for the ABCG2 (a member of the ATP binding cassette transporters) protein explaining their low retention in lung tumor cells expressing this transporter. The compounds in which the chirality at position-3 has been substituted by a non-chiral functionality showed reduced cellular uptake, retention and lower PDT efficacy in mice bearing murine Colon26 tumors. Copyright © 2015 Elsevier Ltd. All rights reserved.

Standardizing foot-type classification using arch index values.

Science.gov (United States)

Wong, Christopher Kevin; Weil, Rich; de Boer, Emily

2012-01-01

The lack of a reliable classification standard for foot type makes drawing conclusions from existing research and clinical decisions difficult, since different foot types may move and respond to treatment differently. The purpose of this study was to determine interrater agreement for foot-type classification based on photo-box-derived arch index values. For this correlational study with two raters, a sample of 11 healthy volunteers with normal to obese body mass indices was recruited from both a community weight-loss programme and a programme in physical therapy. Arch index was calculated using AutoCAD software from footprint photographs obtained via mirrored photo-box. Classification as high-arched, normal, or low-arched foot type was based on arch index values. Reliability of the arch index was determined with intra-class correlations; agreement on foot-type classification was determined using quadratic weighted kappa (κw). Average arch index was 0.215 for one tester and 0.219 for the second tester, with an overall range of 0.017 to 0.370. Both testers classified 6 feet as low-arched, 9 feet as normal, and 7 feet as high-arched. Interrater reliability for the arch index was ICC=0.90; interrater agreement for foot-type classification was κw=0.923. Classification of foot type based on arch index values derived from plantar footprint photographs obtained via mirrored photo-box showed excellent reliability in people with varying BMI. Foot-type classification may help clinicians and researchers subdivide sample populations to better differentiate mobility, gait, or treatment effects among foot types.

Standardizing Foot-Type Classification Using Arch Index Values

Science.gov (United States)

Weil, Rich; de Boer, Emily

2012-01-01

ABSTRACT Purpose: The lack of a reliable classification standard for foot type makes drawing conclusions from existing research and clinical decisions difficult, since different foot types may move and respond to treatment differently. The purpose of this study was to determine interrater agreement for foot-type classification based on photo-box-derived arch index values. Method: For this correlational study with two raters, a sample of 11 healthy volunteers with normal to obese body mass indices was recruited from both a community weight-loss programme and a programme in physical therapy. Arch index was calculated using AutoCAD software from footprint photographs obtained via mirrored photo-box. Classification as high-arched, normal, or low-arched foot type was based on arch index values. Reliability of the arch index was determined with intra-class correlations; agreement on foot-type classification was determined using quadratic weighted kappa (κw). Results: Average arch index was 0.215 for one tester and 0.219 for the second tester, with an overall range of 0.017 to 0.370. Both testers classified 6 feet as low-arched, 9 feet as normal, and 7 feet as high-arched. Interrater reliability for the arch index was ICC=0.90; interrater agreement for foot-type classification was κw=0.923. Conclusions: Classification of foot type based on arch index values derived from plantar footprint photographs obtained via mirrored photo-box showed excellent reliability in people with varying BMI. Foot-type classification may help clinicians and researchers subdivide sample populations to better differentiate mobility, gait, or treatment effects among foot types. PMID:23729964

Remote Cherenkov imaging-based quality assurance of a magnetic resonance image-guided radiotherapy system.

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Andreozzi, Jacqueline M; Mooney, Karen E; Brůža, Petr; Curcuru, Austen; Gladstone, David J; Pogue, Brian W; Green, Olga

2018-06-01

Tools to perform regular quality assurance of magnetic resonance image-guided radiotherapy (MRIgRT) systems should ideally be independent of interference from the magnetic fields. Remotely acquired optical Cherenkov imaging-based dosimetry measurements in water were investigated for this purpose, comparing measures of dose accuracy, temporal dynamics, and overall integrated IMRT delivery. A 40 × 30.5 × 37.5 cm 3 water tank doped with 1 g/L of quinine sulfate was imaged using an intensified charge-coupled device (ICCD) to capture the Cherenkov emission while being irradiated by a commercial MRIgRT system (ViewRay™). The ICCD was placed down-bore at the end of the couch, 4 m from treatment isocenter and behind the 5-Gauss line of the 0.35-T MRI. After establishing optimal camera acquisition settings, square beams of increasing size (4.2 × 4.2 cm 2 , 10.5 × 10.5 cm 2 , and 14.7 × 14.7 cm 2 ) were imaged at 0.93 frames per second, from an individual cobalt-60 treatment head, to develop projection measures related to percent depth dose (PDD) curves and cross beam profiles (CPB). These Cherenkov-derived measurements were compared to ionization chamber (IC) and radiographic film dosimetry data, as well as simulation data from the treatment planning system (TPS). An intensity-modulated radiotherapy (IMRT) commissioning plan from AAPM TG-119 (C4:C-Shape) was also imaged at 2.1 frames per second, and the single linear sum image from 509 s of plan delivery was compared to the dose volume prediction generated by the TPS using gamma index analysis. Analysis of standardized test target images (1024 × 1024 pixels) yielded a pixel resolution of 0.37 mm/pixel. The beam width measured from the Cherenkov image-generated projection CBPs was within 1 mm accuracy when compared to film measurements for all beams. The 502 point measurements (i.e., pixels) of the Cherenkov image-based projection percent depth dose curves (pPDDs) were compared to p

Non-Gaussian diffusion MR imaging of glioma: comparisons of multiple diffusion parameters and correlation with histologic grade and MIB-1 (Ki-67 labeling) index

Energy Technology Data Exchange (ETDEWEB)

Yan, Ren; Haopeng, Pang; Xiaoyuan, Feng; Jiawen, Zhang; Zhenwei, Yao [Fudan University, Department of Radiology, Huashan Hospital, Shanghai (China); Jinsong, Wu; Chengjun, Yao; Tianming, Qiu [Fudan University, Department of Neurosurgery, Huashan Hospital, Shanghai (China); Ji, Xiong [Fudan University, Department of Neuropathology, Huashan Hospital, Shanghai (China); Mao, Sheng; Yueyue, Ding [Department of Imaging, Suzhou Children' s Hospital, Suzhou, Jiangsu (China); Yong, Zhang [MR Research, GE Healthcare, Shanghai (China); Jianfeng, Luo [Fudan University, Department of Biostatistics, Public Health School, Shanghai (China)

2016-02-15

This study was conducted to compare the association of Gaussian and non-Gaussian magnetic resonance imaging (MRI)-derived parameters with histologic grade and MIB-1 (Ki-67 labeling) index (MI) in brain glioma. Sixty-five patients with pathologically confirmed glioma, who underwent diffusion-weighted MRI with 2 b values (0, 1000 s/mm{sup 2}) and 22 b values (≤5000 s/mm{sup 2}), respectively, were divided into three groups of grade II (n = 35), grade III (n = 8), and grade IV (n = 22). Comparisons by two groups were made for apparent diffusion coefficient (ADC), slow diffusion coefficient (Dslow), distributed diffusion coefficient (DDC), and heterogeneity index α. Analyses of receiver operating characteristic (ROC) curve were performed to maximize the area under the curve (AUC) for differentiating grade III + IV (high-grade glioma, HGG) from grade II (low-grade glioma, LGG) and grade IV (glioblastoma multiforme, GBM) from grade II + III (other grade glioma, OGG). Correlations with MI were analyzed for the MRI parameters. On tumor regions, the values of ADC, Dslow, DDC, and α were significantly higher in grade II [(1.37 ± 0.29, 0.70 ± 0.11, 1.39 ± 0.34) (x 10{sup -3} mm{sup 2}/s) and 0.88 ± 0.05, respectively] than in grade III [(0.99 ± 0.13, 0.55 ± 0.07, 1.04 ± 0.20) (x 10{sup -3} mm{sup 2}/s) and 0.80 ± 0.03, respectively] and grade IV [(1.03 ± 0.14, 0.50 ± 0.05, 1.02 ± 0.16) (x 10{sup -3} mm{sup 2}/s) and 0.76 ± 0.04, respectively] (all P < 0.001). The parameter α showed the highest AUCs of 0.950 and 0.922 in discriminating HGG from LGG and GBM from OGG, respectively. Significant correlations with histologic grade and MI were observed for the MRI parameters. The non-Gaussian MRI-derived parameters α and Dslow are superior to ADC in glioma grading, which are comparable with ADC as reliable biomarkers in noninvasively predicting the proliferation level of glioma malignancy. (orig.)

Non-Gaussian diffusion MR imaging of glioma: comparisons of multiple diffusion parameters and correlation with histologic grade and MIB-1 (Ki-67 labeling) index

International Nuclear Information System (INIS)

Yan, Ren; Haopeng, Pang; Xiaoyuan, Feng; Jiawen, Zhang; Zhenwei, Yao; Jinsong, Wu; Chengjun, Yao; Tianming, Qiu; Ji, Xiong; Mao, Sheng; Yueyue, Ding; Yong, Zhang; Jianfeng, Luo

2016-01-01

This study was conducted to compare the association of Gaussian and non-Gaussian magnetic resonance imaging (MRI)-derived parameters with histologic grade and MIB-1 (Ki-67 labeling) index (MI) in brain glioma. Sixty-five patients with pathologically confirmed glioma, who underwent diffusion-weighted MRI with 2 b values (0, 1000 s/mm 2 ) and 22 b values (≤5000 s/mm 2 ), respectively, were divided into three groups of grade II (n = 35), grade III (n = 8), and grade IV (n = 22). Comparisons by two groups were made for apparent diffusion coefficient (ADC), slow diffusion coefficient (Dslow), distributed diffusion coefficient (DDC), and heterogeneity index α. Analyses of receiver operating characteristic (ROC) curve were performed to maximize the area under the curve (AUC) for differentiating grade III + IV (high-grade glioma, HGG) from grade II (low-grade glioma, LGG) and grade IV (glioblastoma multiforme, GBM) from grade II + III (other grade glioma, OGG). Correlations with MI were analyzed for the MRI parameters. On tumor regions, the values of ADC, Dslow, DDC, and α were significantly higher in grade II [(1.37 ± 0.29, 0.70 ± 0.11, 1.39 ± 0.34) (x 10 -3 mm 2 /s) and 0.88 ± 0.05, respectively] than in grade III [(0.99 ± 0.13, 0.55 ± 0.07, 1.04 ± 0.20) (x 10 -3 mm 2 /s) and 0.80 ± 0.03, respectively] and grade IV [(1.03 ± 0.14, 0.50 ± 0.05, 1.02 ± 0.16) (x 10 -3 mm 2 /s) and 0.76 ± 0.04, respectively] (all P < 0.001). The parameter α showed the highest AUCs of 0.950 and 0.922 in discriminating HGG from LGG and GBM from OGG, respectively. Significant correlations with histologic grade and MI were observed for the MRI parameters. The non-Gaussian MRI-derived parameters α and Dslow are superior to ADC in glioma grading, which are comparable with ADC as reliable biomarkers in noninvasively predicting the proliferation level of glioma malignancy. (orig.)

Monosodium glutamate derived tricolor fluorescent carbon nanoparticles for cell-imaging application.

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Zheng, Nannan; Ding, Sha; Zhou, Xingping

2016-06-01

Fluorescent carbon nanoparticle (FCN) is a new type of carbon-based materials. Because of its wide raw material sources, excellent optical properties and good biocompatibility, FCN is getting more and more attentions. However, its synthesis from resources at low cost under mild conditions is still a challenge. Here we report a novel and simple method derived from monosodium glutamate carbonization to make tricolor fluorescent carbon nanoparticles with an average size below 10nm, a high yield up to 35.2% based on the carbon content in the resource, a long life-time of 3.71ns, and a high fluorescence quantum yield up to 51.5% by using quinine sulfate as the standard substance. We discovered that the fluorescent stability of the FCNs was very excellent under UV irradiation for hours in aqueous solutions of pH ranged from 2.0 to 9.0. The cell viability tested under a pretty high concentration of FCNs indicated their safety for biological applications. Based on their high fluorescence quantum efficiency and the advantages mentioned above, these FCNs were then used for cell imaging and exhibited a perfect performance under 3 kinds of excitation bands (UV, blue, and green lights). Thus, they can be practically applied to immune labeling and imaging in vivo in the near future. Copyright © 2016 Elsevier B.V. All rights reserved.

General Ultrasound Imaging

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Full Text Available ... News Physician Resources Professions Site Index A-Z General Ultrasound Ultrasound imaging uses sound waves to produce ... the limitations of General Ultrasound Imaging? What is General Ultrasound Imaging? Ultrasound is safe and painless, and ...

Application of second derivative spectroscopy for increasing molecular specificity of Fourier transform infrared spectroscopic imaging of articular cartilage.

Science.gov (United States)

Rieppo, L; Saarakkala, S; Närhi, T; Helminen, H J; Jurvelin, J S; Rieppo, J

2012-05-01

Fourier transform infrared (FT-IR) spectroscopic imaging is a promising method that enables the analysis of spatial distribution of biochemical components within histological sections. However, analysis of FT-IR spectroscopic data is complicated since absorption peaks often overlap with each other. Second derivative spectroscopy is a technique which enhances the separation of overlapping peaks. The objective of this study was to evaluate the specificity of the second derivative peaks for the main tissue components of articular cartilage (AC), i.e., collagen and proteoglycans (PGs). Histological bovine AC sections were measured before and after enzymatic removal of PGs. Both formalin-fixed sections (n = 10) and cryosections (n = 6) were investigated. Relative changes in the second derivative peak heights caused by the removal of PGs were calculated for both sample groups. The results showed that numerous peaks, e.g., peaks located at 1202 cm(-1) and 1336 cm(-1), altered less than 5% in the experiment. These peaks were assumed to be specific for collagen. In contrast, two peaks located at 1064 cm(-1) and 1376 cm(-1) were seen to alter notably, approximately 50% or more. These peaks were regarded to be specific for PGs. The changes were greater in cryosections than formalin-fixed sections. The results of this study suggest that the second derivative spectroscopy offers a practical and more specific method than routinely used absorption spectrum analysis methods to obtain compositional information on AC with FT-IR spectroscopic imaging. Copyright © 2012 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Nanostructures Derived from Starch and Chitosan for Fluorescence Bio-Imaging

Science.gov (United States)

Zu, Yinxue; Bi, Jingran; Yan, Huiping; Wang, Haitao; Song, Yukun; Zhu, Bei-Wei; Tan, Mingqian

2016-01-01

Fluorescent nanostructures (NSs) derived from polysaccharides have drawn great attention as novel fluorescent probes for potential bio-imaging applications. Herein, we reported a facile alkali-assisted hydrothermal method to fabricate polysaccharide NSs using starch and chitosan as raw materials. Transmission electron microscopy (TEM) demonstrated that the average particle sizes are 14 nm and 75 nm for starch and chitosan NSs, respectively. Fourier transform infrared (FT-IR) spectroscopy analysis showed that there are a large number of hydroxyl or amino groups on the surface of these polysaccharide-based NSs. Strong fluorescence with an excitation-dependent emission behaviour was observed under ultraviolet excitation. Interestingly, the photostability of the NSs was found to be superior to fluorescein and rhodamine B. The quantum yield of starch NSs could reach 11.12% under the excitation of 360 nm. The oxidative metal ions including Cu(II), Hg(II)and Fe(III) exhibited a quench effect on the fluorescence intensity of the prepared NSs. Both of the two kinds of the multicoloured NSs showed a maximum fluorescence intensity at pH 7, while the fluorescence intensity decreased dramatically when they were put in an either acidic or basic environment (at pH 3 or 11). The cytotoxicity study of starch NSs showed that low cell cytotoxicity and 80% viability was found after 24 h incubation, when their concentration was less than 10 mg/mL. The study also showed the possibility of using the multicoloured starch NSs for mouse melanoma cells and guppy fish imaging. PMID:28335258

Synthesis and biological evaluation of novel radioiodinated imidazopyridine derivatives for amyloid-β imaging in Alzheimer's disease.

Science.gov (United States)

Chen, Chun-Jen; Bando, Kazunori; Ashino, Hiroki; Taguchi, Kazumi; Shiraishi, Hideaki; Fujimoto, Osuke; Kitamura, Chiemi; Matsushima, Satoshi; Fujinaga, Masayuki; Zhang, Ming-Rong; Kasahara, Hiroyuki; Minamizawa, Takao; Jiang, Cheng; Ono, Maiko; Higuchi, Makoto; Suhara, Tetsuya; Yamada, Kazutaka; Ji, Bin

2014-08-01

Non-invasive detection for amyloid-β peptide (Aβ) deposition has important significance for the early diagnosis and medical intervention for Alzheimer's disease (AD). In this study, we developed a series of imidazopyridine derivatives as potential imaging agents for single-photon emission computed tomography (SPECT). Two of them, compounds DRK092 and DRM106, showed higher affinity for synthetic human Aβ 1-40 fibrils than did the well-known amyloid-imaging agent IMPY. A metabolite analysis revealed brain-permeable radioactive metabolites of (125)I-labeled DRK092 and IMPY; no radioactive metabolites from (125)I-labeled DRM106 ([(125)I]DRM106) were detected. In addition, in vitro autoradiography clearly demonstrated specific binding of [(125)I]DRM106 in the hippocampal region of AD enriched with Aβ plaques. Thus, our results strongly suggested that compound DRM106 can be used as an imaging agent for SPECT to detect Aβ deposition in AD brain. Copyright © 2014 Elsevier Ltd. All rights reserved.

Development of new index for forest fire risk using satellite images in Indonesia through the direct spectral measurements of soil

Science.gov (United States)

Hashimoto, A.; Akita, M.; Takahashi, Y.; Suzuki, H.; Hasegawa, Y.; Ogino, Y.; Naruse, N.; Takahashi, Y.

2016-12-01

In recent years, the smoke caused by the forest fires in Indonesia has become a serious problem. Most of the land in Indonesia is covered with peat moss, which occurs the expanding of fires due to the burning itself. Thus, the surface soil water, reflecting the amount of precipitation in the area, can become the indication of the risk of fires. This study aims to develop a new index reflecting the risk of forest fires in Indonesia using satellite remote sensing through the direct spectral measurements of peat moss soil.We have prepared the peat moss in 7 steps of soil water content measured at an accuracy of ±15 percent (Field pro, WD-3). We obtained spectra between 400nm and 1050nm (Source: halogen lamp, spectroscope: self-made space time, spectral analysis kit) from the peat moss.The obtained spectra show the difference from the previous spectral measurement for the soil in various water content. There are the features, especially, in the wavelength range of ultraviolet (400-450nm) and infrared (530-800nm) as shown in the figure; the more the soil water increases, the lower the reflectance becomes. We have developed a new index using the New deep blue band (433 453nm and NIR band 845 885nm of Landsat 8. The resulting satellite images calculated by our original index appears to reflect the risk of forest fires rather than well-known indices such as Normalized Difference Water Index and Normalized difference Soil Index.In conclusion, we have created a new index that highly reflects to the degree of soil water of a peat soil in Indonesia.

Bis-pyridinium quadrupolar derivatives. High Stokes shift selective probes for bio-imaging

Science.gov (United States)

Salice, Patrizio; Versari, Silvia; Bradamante, Silvia; Meinardi, Francesco; Macchi, Giorgio; Pagani, Giorgio A.; Beverina, Luca

2013-11-01

We describe the design, synthesis and characterization of five high Stokes shift quadrupolar heteroaryl compounds suitable as fluorescent probes in bio-imaging. In particular, we characterize the photophysical properties and the intracellular localization in Human Umbilical Vein Endothelial Cells (HUVEC) and Human Mesenchymal Stem Cells (HMSCs) for each dye. We show that, amongst all of the investigated derivatives, the 2,5-bis[1-(4-N-methylpyridinium)ethen-2-yl)]- N-methylpyrrole salt is the best candidates as selective mitochondrial tracker. Finally, we recorded the full emission spectrum of the most performing - exclusively mitochondrial selective - fluorescent probe directly from HUVEC stained cells. The emission spectrum collected from the stained mitochondria shows a remarkably more pronounced vibronic structure with respect to the emission of the free fluorophore in solution.

Treatment of Experimental Brain Tumors with Trombospondin-1 Derived Peptides: an In Vivo Imaging Study

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A. Bogdanov, Jr.

1999-11-01

Full Text Available Antiangiogenic and antiproliferative effects of synthetic D-reverse peptides derived from the type 1 repeats of thrombospondin (TSP1 [1,2] were studied in rodent C6 glioma and 9L gliosarcomas. To directly measure tumor size and vascular parameters, we employed in vivo magnetic resonance (MR imaging and corroborated results by traditional morphometric tissue analysis. Rats bearing either C6 or 9L tumors were treated with TSP1-derived peptide (D-reverse amKRFKQDGGWSHWSPWSSac, n=13 or a control peptide (D-reverse am KRAKQAGGASHASPASSac, n=12 at 10 mg/kg, administered either intravenously or through subcutaneous miniosmotic pumps starting 10 days after tumor implantation. Eleven days later, the effect of peptide treatment was evaluated. TSP1 peptide-treated 9L tumors (50.7±44.2 mm3, n=7 and C6 tumors (41.3±34.2 mm3, n=6 were significantly smaller than tumors treated with control peptide (9L: 215.7±67.8 mm3, n=6; C6:184.2±105.2 mm3, n=6. In contrast, the in vivo vascular volume fraction, the mean vascular area (determined by microscopy, and the microvascular density of tumors were not significantly different in any of the experimental groups. In cell culture, TSP1, and the amKRFKQDGGWSHWSPWSSac peptide showed antiproliferative effects against C6 with an IC of 45 nM for TSP1. These results indicate that TSP1derived peptides retard brain tumor growth presumably as a result of slower de novo blood vessel formation and synergistic direct antiproliferative effects on tumor cells. We also show that in vivo MR imaging can be used to assess treatment efficacy of novel antiangiogenic drugs non-invasively, which has obvious implications for clinical trials.

Fast Localization in Large-Scale Environments Using Supervised Indexing of Binary Features.

Science.gov (United States)

Youji Feng; Lixin Fan; Yihong Wu

2016-01-01

The essence of image-based localization lies in matching 2D key points in the query image and 3D points in the database. State-of-the-art methods mostly employ sophisticated key point detectors and feature descriptors, e.g., Difference of Gaussian (DoG) and Scale Invariant Feature Transform (SIFT), to ensure robust matching. While a high registration rate is attained, the registration speed is impeded by the expensive key point detection and the descriptor extraction. In this paper, we propose to use efficient key point detectors along with binary feature descriptors, since the extraction of such binary features is extremely fast. The naive usage of binary features, however, does not lend itself to significant speedup of localization, since existing indexing approaches, such as hierarchical clustering trees and locality sensitive hashing, are not efficient enough in indexing binary features and matching binary features turns out to be much slower than matching SIFT features. To overcome this, we propose a much more efficient indexing approach for approximate nearest neighbor search of binary features. This approach resorts to randomized trees that are constructed in a supervised training process by exploiting the label information derived from that multiple features correspond to a common 3D point. In the tree construction process, node tests are selected in a way such that trees have uniform leaf sizes and low error rates, which are two desired properties for efficient approximate nearest neighbor search. To further improve the search efficiency, a probabilistic priority search strategy is adopted. Apart from the label information, this strategy also uses non-binary pixel intensity differences available in descriptor extraction. By using the proposed indexing approach, matching binary features is no longer much slower but slightly faster than matching SIFT features. Consequently, the overall localization speed is significantly improved due to the much faster key

Fermion fractionization and index theorem

International Nuclear Information System (INIS)

Hirayama, Minoru; Torii, Tatsuo

1982-01-01

The relation between the fermion fractionization and the Callias-Bott-Seeley index theorem for the Dirac operator in the open space of odd dimension is clarified. Only the case of one spatial dimension is discussed in detail. Sum rules for the expectation values of various quantities in fermion-fractionized configurations are derived. (author)

Estimation and Validation of RapidEye-Based Time-Series of Leaf Area Index for Winter Wheat in the Rur Catchment (Germany

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Muhammad Ali

2015-03-01

Full Text Available Leaf Area Index (LAI is an important variable for numerous processes in various disciplines of bio- and geosciences. In situ measurements are the most accurate source of LAI among the LAI measuring methods, but the in situ measurements have the limitation of being labor intensive and site specific. For spatial-explicit applications (from regional to continental scales, satellite remote sensing is a promising source for obtaining LAI with different spatial resolutions. However, satellite-derived LAI measurements using empirical models require calibration and validation with the in situ measurements. In this study, we attempted to validate a direct LAI retrieval method from remotely sensed images (RapidEye with in situ LAI (LAIdestr. Remote sensing LAI (LAIrapideye were derived using different vegetation indices, namely SAVI (Soil Adjusted Vegetation Index and NDVI (Normalized Difference Vegetation Index. Additionally, applicability of the newly available red-edge band (RE was also analyzed through Normalized Difference Red-Edge index (NDRE and Soil Adjusted Red-Edge index (SARE. The LAIrapideye obtained from vegetation indices with red-edge band showed better correlation with LAIdestr (r = 0.88 and Root Mean Square Devation, RMSD = 1.01 & 0.92. This study also investigated the need to apply radiometric/atmospheric correction methods to the time-series of RapidEye Level 3A data prior to LAI estimation. Analysis of the the RapidEye Level 3A data set showed that application of the radiometric/atmospheric correction did not improve correlation of the estimated LAI with in situ LAI.

Tumor imaging and targeting potential of an Hsp70-derived 14-mer peptide.

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Mathias Gehrmann

Full Text Available We have previously used a unique mouse monoclonal antibody cmHsp70.1 to demonstrate the selective presence of a membrane-bound form of Hsp70 (memHsp70 on a variety of leukemia cells and on single cell suspensions derived from solid tumors of different entities, but not on non-transformed cells or cells from corresponding 'healthy' tissue. This antibody can be used to image tumors in vivo and target them for antibody-dependent cellular cytotoxicity. Tumor-specific expression of memHsp70 therefore has the potential to be exploited for theranostic purposes. Given the advantages of peptides as imaging and targeting agents, this study assessed whether a 14-mer tumor penetrating peptide (TPP; TKDNNLLGRFELSG, the sequence of which is derived from the oligomerization domain of Hsp70 which is expressed on the cell surface of tumor cells, can also be used for targeting membrane Hsp70 positive (memHsp70+ tumor cells, in vitro.The specificity of carboxy-fluorescein (CF- labeled TPP (TPP to Hsp70 was proven in an Hsp70 knockout mammary tumor cell system. TPP specifically binds to different memHsp70+ mouse and human tumor cell lines and is rapidly taken up via endosomes. Two to four-fold higher levels of CF-labeled TPP were detected in MCF7 (82% memHsp70+ and MDA-MB-231 (75% memHsp70+ cells compared to T47D cells (29% memHsp70+ that exhibit a lower Hsp70 membrane positivity. After 90 min incubation, TPP co-localized with mitochondrial membranes in memHsp70+ tumors. Although there was no evidence that any given vesicle population was specifically localized, fluorophore-labeled cmHsp70.1 antibody and TPP preferentially accumulated in the proximity of the adherent surface of cultured cells. These findings suggest a potential association between membrane Hsp70 expression and cytoskeletal elements that are involved in adherence, the establishment of intercellular synapses and/or membrane reorganization.This study demonstrates the specific binding and rapid

The second-order differential phase contrast and its retrieval for imaging with x-ray Talbot interferometry

International Nuclear Information System (INIS)

Yang Yi; Tang Xiangyang

2012-01-01

Purpose: The x-ray differential phase contrast imaging implemented with the Talbot interferometry has recently been reported to be capable of providing tomographic images corresponding to attenuation-contrast, phase-contrast, and dark-field contrast, simultaneously, from a single set of projection data. The authors believe that, along with small-angle x-ray scattering, the second-order phase derivative Φ ″ s (x) plays a role in the generation of dark-field contrast. In this paper, the authors derive the analytic formulae to characterize the contribution made by the second-order phase derivative to the dark-field contrast (namely, second-order differential phase contrast) and validate them via computer simulation study. By proposing a practical retrieval method, the authors investigate the potential of second-order differential phase contrast imaging for extensive applications. Methods: The theoretical derivation starts at assuming that the refractive index decrement of an object can be decomposed into δ=δ s +δ f , where δ f corresponds to the object's fine structures and manifests itself in the dark-field contrast via small-angle scattering. Based on the paraxial Fresnel-Kirchhoff theory, the analytic formulae to characterize the contribution made by δ s , which corresponds to the object's smooth structures, to the dark-field contrast are derived. Through computer simulation with specially designed numerical phantoms, an x-ray differential phase contrast imaging system implemented with the Talbot interferometry is utilized to evaluate and validate the derived formulae. The same imaging system is also utilized to evaluate and verify the capability of the proposed method to retrieve the second-order differential phase contrast for imaging, as well as its robustness over the dimension of detector cell and the number of steps in grating shifting. Results: Both analytic formulae and computer simulations show that, in addition to small-angle scattering, the

PAMAM Dendrimers as Potential Carriers of Gadolinium Complexes of Iminodiacetic Acid Derivatives for Magnetic Resonance Imaging

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Magdalena Markowicz-Piasecka

2015-01-01

Full Text Available This is the first study describing the utilization of PAMAM dendrimers as delivery vehicles of novel magnetic resonance imaging (MRI contrast agents. The purpose of this paper was to establish the potential of G4 PAMAM dendrimers as carriers of gadolinium complexes of iminodiacetic acid derivatives and determine imaging properties of synthesized compounds in in vivo studies. Furthermore, we examined the influence of four synthesized complexes on the process of clot formation, stabilization, and lysis and on amidolytic activity of thrombin. Biodistribution studies have shown that the compounds composed of PAMAM G4 dendrimers and gadolinium complexes of iminodiacetic acid derivatives increase signal intensity preferably in liver in range of 59–116% in MRI studies which corresponds with the greatest accumulation of gadolinium after administration of the compounds. Synthesized compounds affect kinetic parameters of the proces of clot formation, its stabilization, and lysis. However, only one synthesized compound at concentration 10-fold higher than potential plasma concentrations contributed to the increase of general parameters such as the overall potential of clot formation and lysis (↑CLAUC and total time of the process (↑T. Results of described studies provide additional insight into delivery properties of PAMAM dendrimers but simultaneously underscore the necessity for further research.

Bounding the HL-index of a graph: a majorization approach.

Science.gov (United States)

Clemente, Gian Paolo; Cornaro, Alessandra

2016-01-01

In mathematical chemistry, the median eigenvalues of the adjacency matrix of a molecular graph are strictly related to orbital energies and molecular orbitals. In this regard, the difference between the occupied orbital of highest energy (HOMO) and the unoccupied orbital of lowest energy (LUMO) has been investigated (see Fowler and Pisansky in Acta Chim. Slov. 57:513-517, 2010). Motivated by the HOMO-LUMO separation problem, Jaklič et al. in (Ars Math. Contemp. 5:99-115, 2012) proposed the notion of HL -index that measures how large in absolute value are the median eigenvalues of the adjacency matrix. Several bounds for this index have been provided in the literature. The aim of the paper is to derive alternative inequalities to bound the HL -index. By applying majorization techniques and making use of some known relations, we derive new and sharper upper bounds for this index. Analytical and numerical results show the performance of these bounds on different classes of graphs.

Assessment of treatment response in nonalcoholic steatohepatitis using advanced magnetic resonance imaging measures

Science.gov (United States)

Lin, Steven C.; Heba, Elhamy; Bettencourt, Ricki; Lin, Grace Y.; Valasek, Mark A.; Lunde, Ottar; Hamilton, Gavin; Sirlin, Claude B.; Loomba, Rohit

2017-01-01

Background Magnetic resonance imaging derived measures of liver fat and volume are emerging as accurate, non-invasive imaging biomarkers in non-alcoholic steatohepatitis (NASH). Little is known about these measures in relation to histology longitudinally. Aims This study examines this relationship between MRI-derived proton-density fat-fraction (PDFF), total liver volume (TLV), total liver fat index (TLFI), vs. histology in a NASH trial. Methods This is a secondary analysis of a 24-week randomized, double-blind, placebo-controlled trial of 50 patients with biopsy-proven NASH randomized to oral ezetimibe 10mg daily (n=25) vs. placebo (n=25). Baseline and post-treatment anthropometrics, biochemical profiling, MRI, and biopsies were obtained. Results Baseline mean PDFF correlated strongly with TLFI (Spearman’s ρ=0.94, n=45, PMRI-PDFF vs. TLV indicates that 10% reduction in MRI-PDFF predicts 257 mL reduction in TLV. Conclusions MRI-PDFF and TLV strongly correlated with TLFI. Decreases in steatosis were associated with an improvement in hepatomegaly. Lower values of these measures reflect lower histologic-steatosis grades. MRI-derived measures of liver fat and volume may be used as dynamic and more responsive imaging biomarkers in a NASH trial than histology. ClinicalTrials.gov number, NCT01766713. PMID:28116801

Conversion of hydroxycinnamic acids into volatile phenols in a synthetic medium and in red wine by Dekkera bruxellensis Transformação de ácidos hidroxicinâmicos em fenóis voláteis em meio sintético e em vinho tinto por Dekkera bruxellensis

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Maria João Cabrita

2012-03-01

Full Text Available The conversion of p-coumaric acid, ferulic acid, and caffeic acid into 4-ethylphenol, 4-ethylguaiacol and 4-ethylcatechol was studied in Dekkera bruxellensis ISA 1791 under defined conditions in a synthetic medium and in a red wine. Liquid chromatography (HPLC-DAD was used to quantify the phenolic acids, and gas chromatography (GC coupled to a FID detector was used to quantify volatile phenols using a novel analytical methodology that does not require sample derivatization. Identification was achieved by gas chromatography-mass detection (GC-MS. The results show that phenolic acids concentration decreases while volatile phenols concentration increases. The proportion of caffeic acid taken up by Dekkera bruxellensis is lower than that for p-coumaric or ferulic acid; therefore less 4-ethylcatechol is formed. More important, 4-ethylcathecol synthesis by Dekkera bruxellensis in wine has never been demonstrated so far. These results contribute decisively to a better understanding of the origin of the volatile phenols in wines. The accumulation of these compounds in wine is nowadays regarded as one of the key factors of quality control.A transformação do ácido p-cumárico, ácido ferúlico e ácido cafeico em 4-etilfenol, 4-etilguaiacol e 4-etilcatecol foi estudada na presença de Dekkera bruxelensis ISA 1791, sob condições controladas, em meio sintético e em vinho tinto. Os compostos fenólicos foram doseados por cromatografia em fase líquida (HPLC-DAD e os fenóis voláteis foram doseados por cromatografia em fase gasosa (GC com detector de ionização de chama (FID, recorrendo a uma metodologia que não requer prévia derivatização da amostra. A identificação dos compostos foi comprovada por espectrometria de massa (GC-MS. Os resultados demonstram que os teores em ácidos fenólicos diminuem enquanto se observa um aumento dos teores em fenóis voláteis. O ácido cafeico é dos três ácidos em estudo, o menos utilizado pela levedura, da

Susceptibility of the wild-derived inbred CAST/Ei mouse to infection by orthopoxviruses analyzed by live bioluminescence imaging

International Nuclear Information System (INIS)

Americo, Jeffrey L.; Sood, Cindy L.; Cotter, Catherine A.; Vogel, Jodi L.; Kristie, Thomas M.; Moss, Bernard; Earl, Patricia L.

2014-01-01

Classical inbred mice are extensively used for virus research. However, we recently found that some wild-derived inbred mouse strains are more susceptible than classical strains to monkeypox virus. Experiments described here indicated that the 50% lethal dose of vaccinia virus (VACV) and cowpox virus (CPXV) were two logs lower in wild-derived inbred CAST/Ei mice than classical inbred BALB/c mice, whereas there was little difference in the susceptibility of the mouse strains to herpes simplex virus. Live bioluminescence imaging was used to follow spread of pathogenic and attenuated VACV strains and CPXV virus from nasal passages to organs in the chest and abdomen of CAST/Ei mice. Luminescence increased first in the head and then simultaneously in the chest and abdomen in a dose-dependent manner. The spreading kinetics was more rapid with VACV than CPXV although the peak photon flux was similar. These data suggest advantages of CAST/Ei mice for orthopoxvirus studies. - Highlights: • Wild-derived inbred CAST/Ei mice are susceptible to vaccinia virus and cowpox virus. • Morbidity and mortality from orthopoxviruses are greater in CAST/Ei than BALB/c mice. • Morbidity and mortality from herpes simplex virus type 1 are similar in both mice. • Imaging shows virus spread from nose to lungs, abdominal organs and brain. • Vaccinia virus spreads more rapidly than cowpox virus

Susceptibility of the wild-derived inbred CAST/Ei mouse to infection by orthopoxviruses analyzed by live bioluminescence imaging

Energy Technology Data Exchange (ETDEWEB)

Americo, Jeffrey L.; Sood, Cindy L.; Cotter, Catherine A.; Vogel, Jodi L.; Kristie, Thomas M.; Moss, Bernard, E-mail: bmoss@nih.gov; Earl, Patricia L., E-mail: pearl@nih.gov

2014-01-20

Classical inbred mice are extensively used for virus research. However, we recently found that some wild-derived inbred mouse strains are more susceptible than classical strains to monkeypox virus. Experiments described here indicated that the 50% lethal dose of vaccinia virus (VACV) and cowpox virus (CPXV) were two logs lower in wild-derived inbred CAST/Ei mice than classical inbred BALB/c mice, whereas there was little difference in the susceptibility of the mouse strains to herpes simplex virus. Live bioluminescence imaging was used to follow spread of pathogenic and attenuated VACV strains and CPXV virus from nasal passages to organs in the chest and abdomen of CAST/Ei mice. Luminescence increased first in the head and then simultaneously in the chest and abdomen in a dose-dependent manner. The spreading kinetics was more rapid with VACV than CPXV although the peak photon flux was similar. These data suggest advantages of CAST/Ei mice for orthopoxvirus studies. - Highlights: • Wild-derived inbred CAST/Ei mice are susceptible to vaccinia virus and cowpox virus. • Morbidity and mortality from orthopoxviruses are greater in CAST/Ei than BALB/c mice. • Morbidity and mortality from herpes simplex virus type 1 are similar in both mice. • Imaging shows virus spread from nose to lungs, abdominal organs and brain. • Vaccinia virus spreads more rapidly than cowpox virus.

Multimodality Molecular Imaging of [18F]-Fluorinated Carboplatin Derivative Encapsulated in [111In]-Labeled Liposomes

Science.gov (United States)

Lamichhane, Narottam

Platinum based chemotherapy is amongst the mainstream DNA-damaging agents used in clinical cancer therapy today. Agents such as cisplatin, carboplatin are clinically prescribed for the treatment of solid tumors either as single agents, in combination, or as part of multi-modality treatment strategy. Despite the potent anti-tumor activity of these drugs, overall effectiveness is still hampered by inadequate delivery and retention of drug in tumor and unwanted normal tissue toxicity, induced by non-selective accumulation of drug in normal cells and tissues. Utilizing molecular imaging and nanoparticle technologies, this thesis aims to contribute to better understanding of how to improve the profile of platinum based therapy. By developing a novel fluorinated derivative of carboplatin, incorporating a Flourine-18 (18F) moiety as an inherent part of the molecule, quantitative measures of drug concentration in tumors and normal tissues can be directly determined in vivo and within the intact individual environment. A potential impact of this knowledge will be helpful in predicting the overall response of individual patients to the treatment. Specifically, the aim of this project, therefore, is the development of a fluorinated carboplatin drug derivative with an inherent positron emission tomography (PET) imaging capability, so that the accumulation of the drug in the tumor and normal organs can be studied during the course of therapy . A secondary objective of this research is to develop a proof of concept for simultaneous imaging of a PET radiolabeled drug with a SPECT radiolabeled liposomal formulation, enabling thereby bi-modal imaging of drug and delivery vehicle in vivo. The approach is challenging because it involves development in PET radiochemistry, PET and SPECT imaging, drug liposomal encapsulation, and a dual-modal imaging of radiolabeled drug and radiolabeled vehicle. The principal development is the synthesis of fluorinated carboplatin 19F-FCP using 2

Transient stability index for online stability assessment and contingency evaluation

Energy Technology Data Exchange (ETDEWEB)

Ribbens-Pavella, M; Murthy, P G; Horward, J L; Carpentier, J L

1982-04-01

An on-line methodology is proposed for assessing the robustness of a power system from the point of view of transient stability, and a scalar expression, the transient stability index, is accordingly derived. The reliability and sensitivity of this index are tested by means of simulations for a number of power system cases. The index is shown to be appropriate for online stability assessment, contingency evaluation and preventive control. 14 refs.

Large-Scale Partial-Duplicate Image Retrieval and Its Applications

Science.gov (United States)

2016-04-23

tree based image retrieval , a semantic-aware co-indexing algorithm is proposed to jointly embed two strong cues into the inverted indexes: 1) local...based image retrieval , a semantic-aware co-indexing algorithm is proposed to jointly embed two strong cues into the inverted indexes: 1) local...Distribution Unlimited UU UU UU UU 23-04-2016 23-Jan-2012 22-Jan-2016 Final Report: Large-Scale Partial-Duplicate Image Retrieval and Its Applications

Thermally activated delayed fluorescence of fluorescein derivative for time-resolved and confocal fluorescence imaging.

Science.gov (United States)

Xiong, Xiaoqing; Song, Fengling; Wang, Jingyun; Zhang, Yukang; Xue, Yingying; Sun, Liangliang; Jiang, Na; Gao, Pan; Tian, Lu; Peng, Xiaojun

2014-07-09

Compared with fluorescence imaging utilizing fluorophores whose lifetimes are in the order of nanoseconds, time-resolved fluorescence microscopy has more advantages in monitoring target fluorescence. In this work, compound DCF-MPYM, which is based on a fluorescein derivative, showed long-lived luminescence (22.11 μs in deaerated ethanol) and was used in time-resolved fluorescence imaging in living cells. Both nanosecond time-resolved transient difference absorption spectra and time-correlated single-photon counting (TCSPC) were employed to explain the long lifetime of the compound, which is rare in pure organic fluorophores without rare earth metals and heavy atoms. A mechanism of thermally activated delayed fluorescence (TADF) that considers the long wavelength fluorescence, large Stokes shift, and long-lived triplet state of DCF-MPYM was proposed. The energy gap (ΔEST) of DCF-MPYM between the singlet and triplet state was determined to be 28.36 meV by the decay rate of DF as a function of temperature. The ΔE(ST) was small enough to allow efficient intersystem crossing (ISC) and reverse ISC, leading to efficient TADF at room temperature. The straightforward synthesis of DCF-MPYM and wide availability of its starting materials contribute to the excellent potential of the compound to replace luminescent lanthanide complexes in future time-resolved imaging technologies.

Land Cover Classification Using Integrated Spectral, Temporal, and Spatial Features Derived from Remotely Sensed Images

Directory of Open Access Journals (Sweden)

Yongguang Zhai

2018-03-01

Full Text Available Obtaining accurate and timely land cover information is an important topic in many remote sensing applications. Using satellite image time series data should achieve high-accuracy land cover classification. However, most satellite image time-series classification methods do not fully exploit the available data for mining the effective features to identify different land cover types. Therefore, a classification method that can take full advantage of the rich information provided by time-series data to improve the accuracy of land cover classification is needed. In this paper, a novel method for time-series land cover classification using spectral, temporal, and spatial information at an annual scale was introduced. Based on all the available data from time-series remote sensing images, a refined nonlinear dimensionality reduction method was used to extract the spectral and temporal features, and a modified graph segmentation method was used to extract the spatial features. The proposed classification method was applied in three study areas with land cover complexity, including Illinois, South Dakota, and Texas. All the Landsat time series data in 2014 were used, and different study areas have different amounts of invalid data. A series of comparative experiments were conducted on the annual time-series images using training data generated from Cropland Data Layer. The results demonstrated higher overall and per-class classification accuracies and kappa index values using the proposed spectral-temporal-spatial method compared to spectral-temporal classification methods. We also discuss the implications of this study and possibilities for future applications and developments of the method.

W-transform method for feature-oriented multiresolution image retrieval

Energy Technology Data Exchange (ETDEWEB)

Kwong, M.K.; Lin, B. [Argonne National Lab., IL (United States). Mathematics and Computer Science Div.

1995-07-01

Image database management is important in the development of multimedia technology. Since an enormous amount of digital images is likely to be generated within the next few decades in order to integrate computers, television, VCR, cables, telephone and various imaging devices. Effective image indexing and retrieval systems are urgently needed so that images can be easily organized, searched, transmitted, and presented. Here, the authors present a local-feature-oriented image indexing and retrieval method based on Kwong, and Tang`s W-transform. Multiresolution histogram comparison is an effective method for content-based image indexing and retrieval. However, most recent approaches perform multiresolution analysis for whole images but do not exploit the local features present in the images. Since W-transform is featured by its ability to handle images of arbitrary size, with no periodicity assumptions, it provides a natural tool for analyzing local image features and building indexing systems based on such features. In this approach, the histograms of the local features of images are used in the indexing, system. The system not only can retrieve images that are similar or identical to the query images but also can retrieve images that contain features specified in the query images, even if the retrieved images as a whole might be very different from the query images. The local-feature-oriented method also provides a speed advantage over the global multiresolution histogram comparison method. The feature-oriented approach is expected to be applicable in managing large-scale image systems such as video databases and medical image databases.

Heel–Ball index: An analysis of footprint dimensions for determination of sex

Directory of Open Access Journals (Sweden)

Tanuj Kanchan

2014-06-01

Full Text Available Determination of sex from the footprints recovered at crime scenes can help the investigation by narrowing down the pool of possible suspects. The present research studies the dimensions of the heel and the ball in footprints, and derives the Heel–Ball (HB index from these foot dimensions with the aim to find out if the foot dimensions and the HB index exhibit sexual dimorphisms. The study was carried out on 100 individuals (50 males, 50 females of Indian origin. Footprints were obtained from both feet of the study participants using standard techniques. Thus, a total of 200 footprints were obtained. The breadth of the footprint at ball (BBAL and the breadth of the footprint at heel (BHEL were measured on the footprints. The HB index was derived as (BHEL ÷ BBAL × 100. The footprint measurements at the ball and heel were significantly larger in males on both the sides. Likewise, the derived HB index was larger in males in both feet, but the sex differences were not statistically significant. The study concludes that though footprint dimensions can be used in the determination of sex, the HB index may not be utilized in sex determination from footprints.

FRELIB, Failure Reliability Index Calculation

International Nuclear Information System (INIS)

Parkinson, D.B.; Oestergaard, C.

1984-01-01

1 - Description of problem or function: Calculation of the reliability index given the failure boundary. A linearization point (design point) is found on the failure boundary for a stationary reliability index (min) and a stationary failure probability density function along the failure boundary, provided that the basic variables are normally distributed. 2 - Method of solution: Iteration along the failure boundary which must be specified - together with its partial derivatives with respect to the basic variables - by the user in a subroutine FSUR. 3 - Restrictions on the complexity of the problem: No distribution information included (first-order-second-moment-method). 20 basic variables (could be extended)

Evaluation of vegetation cover using the normalized difference vegetation index (NDVI

Directory of Open Access Journals (Sweden)

Gabriela Camargos Lima

2013-08-01

Full Text Available Soil loss by water erosion is the main cause of soil degradation in Brazil. However, erosion can be reduced by the presence of vegetation. The Normalized Difference Vegetation Index (NDVI makes it possible to identify the vegetative vigor of crops or natural vegetation which facilities the identification of areas with vegetation covers. This information is very important in identifying the phenomena which might be occurring in a particular area, especially those related to soil degradation by water erosion. Thus, the aim of this work was to assess the canopy cover by using NDVI, checking the image accuracy using the Coverage Index (CI based on the Stocking method, in the Sub-basin of Posses, which belongs to the Cantareira System, located in the Extrema municipality, Minas Gerais, Brazil. Landsat-5 TM images were used. The sub-basin of Posses was very altered in comparison to the surrounding areas. The NDVI technique proved to be a suitable tool to assess the uses that occur in the sub-basin of Posses, as validated by the Stocking methodology. The map derived from NDVI allowed the geographic distribution of different land uses to be observed and allowed for the identification of critical areas in relation to vegetation cover as well. This finding can be used to optimize efforts to recover and protect soil in areas with bare soil and degraded pasture, in order to reduce environmental degradation. The CI has not exceeded 40% for land use classes that occur in the majority of the sub-basin (91%, except in areas of woody vegetation.

An Associative Index Model for the Results List Based on Vannevar Bush's Selection Concept

Science.gov (United States)

Cole, Charles; Julien, Charles-Antoine; Leide, John E.

2010-01-01

Introduction: We define the results list problem in information search and suggest the "associative index model", an ad-hoc, user-derived indexing solution based on Vannevar Bush's description of an associative indexing approach for his memex machine. We further define what selection means in indexing terms with reference to Charles…

Comparison of a new composite index based on midlatency auditory evoked potentials and electroencephalographic parameters with bispectral index (BIS) during moderate propofol sedation.

Science.gov (United States)

Hadzidiakos, D; Petersen, S; Baars, J; Herold, K; Rehberg, B

2006-11-01

Derived parameters of the electroencephalogram and auditory evoked potentials can be used to determine depth of anaesthesia and sedation. However, it is not known whether any parameter can identify the occurrence of awareness in individual patients. We have compared the performance of bispectral index and a new composite index derived from auditory evoked potentials and the electroencephalogram (AAI 1.61) in predicting consciousness, explicit and implicit memory during moderate sedation with propofol. Twenty-one patients with spinal anaesthesia received intraoperatively propofol at the age-corrected C(50) for loss of consciousness and were presented test words via headphones. Bispectral index and AAI 1.61 (auditory evoked potentials, AEP-Monitor2) were recorded in parallel as well as the Observer's Assessment of Alertness/Sedation-score. Postoperatively, testing for explicit and implicit memory formation was performed. Bispectral index and AAI 1.61 correlated well with loss of consciousness defined by an Observer's Assessment of Alertness/Sedation-score of 2 (identical P(K) of 0.87), but did not allow a prediction of postoperative explicit or implicit recall. Both bispectral index and AAI may be indices of depth of sedation rather than indicators of memory formation, which persists during propofol sedation even after loss of consciousness.

CRED Fagatele Bay National Marine Sanctuary Bathymetric Position Index Habitat Zones 2004

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetric Position Index (BPI) Zones derived from derivatives of Simrad EM-3000 multibeam bathymetry (3 m resolution). BPI zones are surficial characteristics of...

Optical waves in a gradient negative-index lens of a half-infinite length.

Science.gov (United States)

Ding, Yi S; Chan, C T; Wang, R P

2013-10-16

Materials with negative permittivity and permeability can overcome the diffraction limit, thereby making the sub-wavelength imaging possible. In this study, we analyze the effects of gradient index on a half-infinite perfect lens. We assume that the sharp interface between the vacuum and the negative-index material is replaced by a smooth transition profile such that the index gradually changing from positive to negative. Interestingly, we find that if the graded index profile is modeled by a tanh function, we can have closed-form analytical solutions for this problem, which is a distinct advantage as numerical solutions are not accurate for evanescent waves with large transverse wave vectors. By analyzing the analytical formulas we confirm that a nonzero total absorption can occur even for a near-zero absorption coefficient in the steady-state limit and the image plane contains multiple sub-wavelength images of an object.

Influences of overlap index on Fourier ptychography imaging

Science.gov (United States)

Wang, Honghong; Rong, Lu; Wang, Dayong; Zhang, Xu; Zhai, Changchao; Panezai, Spozmai; Wang, Yunxin; Zhao, Jie

2018-01-01

Fourier ptychography is a new type of synthetic aperture imaging technique based on phase retrieval method which can improve microscopeic imaging performance beyond the diffraction limit of the employed optical components by illuminating the object with oblique waves of different incident angles where the field of view remains unchanged. illumination angle and the overlap rate of spectrum will have a certain impact on the quality of reconstruction. In this paper, we study the effects of illumination angle and spectral overlap rate on the image quality of Fourier ptychography. The simulation results show that increasing the illumination angle and spectral overlap can improve the resolution, but there is a threshold for the key parameters of spectral overlap rate. The convergence rate decreases when the overlap rate exceeds 70%, and the reconstruction process is more time-consuming due to the high overlap rate. However the results of proposed study shows that an overlap of 60% is the optimal choice to acquire a high-quality recovery with high speed.

Validation of ozone monitoring instrument ultraviolet index against ground-based UV index in Kampala, Uganda.

Science.gov (United States)

Muyimbwa, Dennis; Dahlback, Arne; Ssenyonga, Taddeo; Chen, Yi-Chun; Stamnes, Jakob J; Frette, Øyvind; Hamre, Børge

2015-10-01

The Ozone Monitoring Instrument (OMI) overpass solar ultraviolet (UV) indices have been validated against the ground-based UV indices derived from Norwegian Institute for Air Research UV measurements in Kampala (0.31° N, 32.58° E, 1200 m), Uganda for the period between 2005 and 2014. An excessive use of old cars, which would imply a high loading of absorbing aerosols, could cause the OMI retrieval algorithm to overestimate the surface UV irradiances. The UV index values were found to follow a seasonal pattern with maximum values in March and October. Under all-sky conditions, the OMI retrieval algorithm was found to overestimate the UV index values with a mean bias of about 28%. When only days with radiation modification factor greater than or equal to 65%, 70%, 75%, and 80% were considered, the mean bias between ground-based and OMI overpass UV index values was reduced to 8%, 5%, 3%, and 1%, respectively. The overestimation of the UV index by the OMI retrieval algorithm was found to be mainly due to clouds and aerosols.

Applications of Sentinel-2 data for agriculture and forest monitoring using the absolute difference (ZABUD) index derived from the AgroEye software (ESA)

Science.gov (United States)

de Kok, R.; WeŻyk, P.; PapieŻ, M.; Migo, L.

2017-10-01

To convince new users of the advantages of the Sentinel_2 sensor, a simplification of classic remote sensing tools allows to create a platform of communication among domain specialists of agricultural analysis, visual image interpreters and remote sensing programmers. An index value, known in the remote sensing user domain as "Zabud" was selected to represent, in color, the essentials of a time series analysis. The color index used in a color atlas offers a working platform for an agricultural field control. This creates a database of test and training areas that enables rapid anomaly detection in the agricultural domain. The use cases and simplifications now function as an introduction to Sentinel_2 based remote sensing, in an area that before relies on VHR imagery and aerial data, to serve mainly the visual interpretation. The database extension with detected anomalies allows developers of open source software to design solutions for further agricultural control with remote sensing.

A special vegetation index for the weed detection in sensor based precision agriculture.

Science.gov (United States)

Langner, Hans-R; Böttger, Hartmut; Schmidt, Helmut