An improved yeast transformation method for the generation of very large human antibody libraries.

PubMed

Benatuil, Lorenzo; Perez, Jennifer M; Belk, Jonathan; Hsieh, Chung-Ming

2010-04-01

Antibody library selection by yeast display technology is an efficient and highly sensitive method to identify binders to target antigens. This powerful selection tool, however, is often hampered by the typically modest size of yeast libraries (approximately 10(7)) due to the limited yeast transformation efficiency, and the full potential of the yeast display technology for antibody discovery and engineering can only be realized if it can be coupled with a mean to generate very large yeast libraries. We describe here a yeast transformation method by electroporation that allows for the efficient generation of large antibody libraries up to 10(10) in size. Multiple components and conditions including CaCl(2), MgCl(2), sucrose, sorbitol, lithium acetate, dithiothreitol, electroporation voltage, DNA input and cell volume have been tested to identify the best combination. By applying this developed protocol, we have constructed a 1.4 x 10(10) human spleen antibody library essentially in 1 day with a transformation efficiency of 1-1.5 x 10(8) transformants/microg vector DNA. Taken together, we have developed a highly efficient yeast transformation method that enables the generation of very large and productive human antibody libraries for antibody discovery, and we are now routinely making 10(9) libraries in a day for antibody engineering purposes.

Investigation of magnetic nanoparticle targeting in a simplified model of small vessel aneurysm

NASA Astrophysics Data System (ADS)

Mirzababaei, S. N.; Gorji, Tahereh B.; Baou, M.; Gorji-Bandpy, M.; Fatouraee, Nasser

2017-03-01

An in simulacra study was conducted to investigate the capture efficiency (CE) of magnetic nanoparticles (MNPs) in aneurysm model, under the effect of a bipolar permanent magnetic system positioned at the vicinity of the model vessel. The bipolar magnetic system with an active space of 9 cm was designed by FEMM software. The MNPs were magnetite nanoparticles synthesized by the hydrothermal method which were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscope and magnetometer measurements. Ferrofluid velocity, magnetic field strength, and aneurysm volume all proved to be important parameters which affect the capturing of MNPs. Overall, the results of this in simulacra study confirmed the effectiveness of magnetic targeting for possible aneurysm embolization.

Transform coding for hardware-accelerated volume rendering.

PubMed

Fout, Nathaniel; Ma, Kwan-Liu

2007-01-01

Hardware-accelerated volume rendering using the GPU is now the standard approach for real-time volume rendering, although limited graphics memory can present a problem when rendering large volume data sets. Volumetric compression in which the decompression is coupled to rendering has been shown to be an effective solution to this problem; however, most existing techniques were developed in the context of software volume rendering, and all but the simplest approaches are prohibitive in a real-time hardware-accelerated volume rendering context. In this paper we present a novel block-based transform coding scheme designed specifically with real-time volume rendering in mind, such that the decompression is fast without sacrificing compression quality. This is made possible by consolidating the inverse transform with dequantization in such a way as to allow most of the reprojection to be precomputed. Furthermore, we take advantage of the freedom afforded by off-line compression in order to optimize the encoding as much as possible while hiding this complexity from the decoder. In this context we develop a new block classification scheme which allows us to preserve perceptually important features in the compression. The result of this work is an asymmetric transform coding scheme that allows very large volumes to be compressed and then decompressed in real-time while rendering on the GPU.

The human T-cell leukemia virus type 1 p13II protein: effects on mitochondrial function and cell growth

PubMed Central

D’Agostino, DM; Silic-Benussi, M; Hiraragi, H; Lairmore, MD; Ciminale, V

2011-01-01

p13II of human T-cell leukemia virus type 1 (HTLV-1) is an 87-amino-acid protein that is targeted to the inner mitochondrial membrane. p13II alters mitochondrial membrane permeability, producing a rapid, membrane potential-dependent influx of K+. These changes result in increased mitochondrial matrix volume and fragmentation and may lead to depolarization and alterations in mitochondrial Ca2+ uptake/retention capacity. At the cellular level, p13II has been found to interfere with cell proliferation and transformation and to promote apoptosis induced by ceramide and Fas ligand. Assays carried out in T cells (the major targets of HTLV-1 infection in vivo) demonstrate that p13II-mediated sensitization to Fas ligand-induced apoptosis can be blocked by an inhibitor of Ras farnesylation, thus implicating Ras signaling as a downstream target of p13II function. PMID:15761473

Calculation of Lung Cancer Volume of Target Based on Thorax Computed Tomography Images using Active Contour Segmentation Method for Treatment Planning System

NASA Astrophysics Data System (ADS)

Patra Yosandha, Fiet; Adi, Kusworo; Edi Widodo, Catur

2017-06-01

In this research, calculation process of the lung cancer volume of target based on computed tomography (CT) thorax images was done. Volume of the target calculation was done in purpose to treatment planning system in radiotherapy. The calculation of the target volume consists of gross tumor volume (GTV), clinical target volume (CTV), planning target volume (PTV) and organs at risk (OAR). The calculation of the target volume was done by adding the target area on each slices and then multiply the result with the slice thickness. Calculations of area using of digital image processing techniques with active contour segmentation method. This segmentation for contouring to obtain the target volume. The calculation of volume produced on each of the targets is 577.2 cm3 for GTV, 769.9 cm3 for CTV, 877.8 cm3 for PTV, 618.7 cm3 for OAR 1, 1,162 cm3 for OAR 2 right, and 1,597 cm3 for OAR 2 left. These values indicate that the image processing techniques developed can be implemented to calculate the lung cancer target volume based on CT thorax images. This research expected to help doctors and medical physicists in determining and contouring the target volume quickly and precisely.

Twinning and martensite in a 304 austenitic stainless steel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shen, Yongfeng; Li, Xi; Sun, Xin

2012-08-30

The microstructure characteristics and deformation behavior of 304L stainless steel during tensile deformation at two different strain rates have been investigated by means of interrupted tensile tests, electron-backscatter-diffraction (EBSD) and transmission electron microscopy (TEM) techniques. The volume fractions of transformed martensite and deformation twins at different stages of the deformation process were measured using X-ray diffraction method and TEM observations. It is found that the volume fraction of martensite monotonically increases with increasing strain but decreases with increasing strain rate. On the other hand, the volume fraction of twins increases with increasing strain for strain level less than 57%. Beyondmore » that, the volume fraction of twins decreases with increasing strain. Careful TEM observations show that stacking faults (SFs) and twins preferentially occur before the nucleation of martensite. Meanwhile, both {var_epsilon}-martensite and {alpha}{prime}-martensite are observed in the deformation microstructures, indicating the co-existence of stress induced- transformation and strain-induced-transformation. We also discussed the effects of twinning and martensite transformation on work-hardening as well as the relationship between stacking faults, twinning and martensite transformation.« less

Finite size effects in phase transformation kinetics in thin films and surface layers

NASA Astrophysics Data System (ADS)

Trofimov, Vladimir I.; Trofimov, Ilya V.; Kim, Jong-Il

2004-02-01

In studies of phase transformation kinetics in thin films, e.g. crystallization of amorphous films, until recent time is widely used familiar Kolmogorov-Johnson-Mehl-Avrami (KJMA) statistical model of crystallization despite it is applicable only to an infinite medium. In this paper a model of transformation kinetics in thin films based on a concept of the survival probability for randomly chosen point during transformation process is presented. Two model versions: volume induced transformation (VIT) when the second-phase grains nucleate over a whole film volume and surface induced transformation (SIT) when they form on an interface with two nucleation mode: instantaneous nucleation at transformation onset and continuous one during all the process are studied. At VIT-process due to the finite film thickness effects the transformation profile has a maximum in a film middle, whereas that of the grains population reaches a minimum inhere, the grains density is always higher than in a volume material, and the thinner film the slower it transforms. The transformation kinetics in a thin film obeys a generalized KJMA equation with parameters depending on a film thickness and in limiting cases of extremely thin and thick film it reduces to classical KJMA equation for 2D- and 3D-system, respectively.

System and method for radiation dose calculation within sub-volumes of a monte carlo based particle transport grid

DOEpatents

Bergstrom, Paul M.; Daly, Thomas P.; Moses, Edward I.; Patterson, Jr., Ralph W.; Schach von Wittenau, Alexis E.; Garrett, Dewey N.; House, Ronald K.; Hartmann-Siantar, Christine L.; Cox, Lawrence J.; Fujino, Donald H.

2000-01-01

A system and method is disclosed for radiation dose calculation within sub-volumes of a particle transport grid. In a first step of the method voxel volumes enclosing a first portion of the target mass are received. A second step in the method defines dosel volumes which enclose a second portion of the target mass and overlap the first portion. A third step in the method calculates common volumes between the dosel volumes and the voxel volumes. A fourth step in the method identifies locations in the target mass of energy deposits. And, a fifth step in the method calculates radiation doses received by the target mass within the dosel volumes. A common volume calculation module inputs voxel volumes enclosing a first portion of the target mass, inputs voxel mass densities corresponding to a density of the target mass within each of the voxel volumes, defines dosel volumes which enclose a second portion of the target mass and overlap the first portion, and calculates common volumes between the dosel volumes and the voxel volumes. A dosel mass module, multiplies the common volumes by corresponding voxel mass densities to obtain incremental dosel masses, and adds the incremental dosel masses corresponding to the dosel volumes to obtain dosel masses. A radiation transport module identifies locations in the target mass of energy deposits. And, a dose calculation module, coupled to the common volume calculation module and the radiation transport module, for calculating radiation doses received by the target mass within the dosel volumes.

SU-G-JeP3-12: Use of Cone Beam CT and Deformable Image Registration for Assessing Geometrical and Dosimetric Variations During Lung Radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jurkovic, I; Stathakis, S; Markovic, M

Purpose: To assess the value of cone beam CT (CBCT) combined with deformable image registration in estimating the accuracy of the delivered treatment and the suitability of the applied target margins. Methods: Two patients with lung tumor were selected. Using their CT images intensity modulated radiation therapy (IMRT) treatment plans were developed to deliver 66Gy to the 95% of the PTV in 2Gy fractions. Using the Velocity AI software, the planning CT of each patient was registered with the fractional CBCT images that were obtained through the course of the treatment. After a CT to CBCT deformable image registration (DIR),more » the same fractional deformation matrix was used for the deformation of the planned dose distributions, as well as of all the contoured volumes, to each CBCT dataset. The dosimetric differences between the planning target volume (PTV) and various organs at risk (OARs) were recorded and compared. Results: CBCT data such as CTV volume change and PTV coverage was analyzed. There was a moderate relationship between volume changes and contouring method (automatic contouring using the DIR transformation vs. manual contouring on each CBCT) for patient #1 (r = 0.49), and a strong relationship for patient #2 (r = 0.83). The average PTV volume coverage from all the CBCT datasets was 91.2% for patient #1 and 95.6% for patient #2. Conclusion: Daily setup variations, tumor volume motion and lung deformation due to breathing yield differences in the actual delivered dose distributions versus the planned ones. The results presented indicate that these differences are apparent even with the use of daily IGRT. In certain fractions, the margins used seem to be insufficient to ensure acceptable lung tumor coverage. The observed differences notably depend on the tumor volume size and location. A larger cohort of patient is under investigation to verify those findings.« less

The transformation of targeted killing and international order.

PubMed

Senn, Martin; Troy, Jodok

2017-05-04

This article introduces the special issue's question of whether and how the current transformation of targeted killing is transforming the global international order and provides the conceptual ground for the individual contributions to the special issue. It develops a two-dimensional concept of political order and introduces a theoretical framework that conceives the maintenance and transformation of international order as a dynamic interplay between its behavioral dimension in the form of violence and discursive processes and its institutional dimension in the form of ideas, norms, and rules. The article also conceptualizes targeted killing and introduces a typology of targeted-killing acts on the basis of their legal and moral legitimacy. Building on this conceptual groundwork, the article takes stock of the current transformation of targeted killing and summarizes the individual contributions to this special issue.

Cross-sectional study of variables associated with length of stay and ICU need in open Roux-En-Y gastric bypass surgery for morbid obese patients: an exploratory analysis based on the Public Health System administrative database (Datasus) in Brazil.

PubMed

Asano, Elio Fernando; Rasera, Irineu; Shiraga, Elisabete Cristina

2012-12-01

This is an exploratory analysis of potential variables associated with open Roux-en-Y gastric bypass (RYGB) surgery hospitalization resource use pattern. Cross-sectional study based on an administrative database (DATASUS) records. Inclusion criteria were adult patients undergoing RYGB between Jan/2008 and Jun/2011. Dependent variables were length of stay (LoS) and ICU need. Independent variables were: gender, age, region, hospital volume, surgery at certified center of excellence (CoE) by the Surgical Review Corporation (SRC), teaching hospital, and year of hospitalization. Univariate and multivariate analysis (logistic regression for ICU need and linear regression for length of stay) were performed. Data from 13,069 surgeries were analyzed. In crude analysis, hospital volume was the most impactful variable associated with log-transformed LoS (1.312 ± 0.302 high volume vs. 1.670 ± 0.581 low volume, p < 0.001), whereas for ICU need it was certified CoE (odds ratio (OR), 0.016; 95% confidence interval (CI), 0.010-0.026). After adjustment by logistic regression, certified CoE remained as the strongest predictor of ICU need (OR, 0.011; 95% CI, 0.007-0.018), followed by hospital volume (OR, 3.096; 95% CI, 2.861-3.350). Age group, male gender, and teaching hospital were also significantly associated (p < 0.001). For log-transformed LoS, final model includes hospital volume (coefficient, -0.223; 95% CI, -0.250 to -0.196) and teaching hospital (coefficient, 0.375; 95% CI, 0.351-0.398). Region of Brazil was not associated with any of the outcomes. High-volume hospital was the strongest predictor for shorter LoS, whereas SRC certification was the strongest predictor of lower ICU need. Public health policies targeting an increase of efficiency and patient access to the procedure should take into account these results.

Improved wrist pannus volume measurement from contrast-enhanced MRI in rheumatoid arthritis using shuffle transform.

PubMed

Xanthopoulos, Emily; Hutchinson, Charles E; Adams, Judith E; Bruce, Ian N; Nash, Anthony F P; Holmes, Andrew P; Taylor, Christopher J; Waterton, John C

2007-01-01

Contrast-enhanced MRI is of value in assessing rheumatoid pannus in the hand, but the images are not always easy to quantitate. To develop and evaluate an improved measurement of volume of enhancing pannus (VEP) in the hand in human rheumatoid arthritis (RA). MR images of the hand and wrist were obtained for 14 patients with RA at 0, 1 and 13 weeks. Volume of enhancing pannus was measured on images created by subtracting precontrast T1-weighted images from contrast-enhanced T1-weighted images using a shuffle transformation technique. Maximum intensity projection (MIP) and 3D volume rendering of the images were used as a guide to identify the pannus and any contrast-enhanced veins. Visualisation of pannus was much improved following the shuffle transform. Between 0 weeks and 1 week, the mean value of the within-subject coefficient of variation (CoV) was 0.13 and the estimated total CoV was 0.15. There was no evidence of significant increased variability within the 13-week interval for the complete sample of patients. Volume of enhancing pannus can be measured reproducibly in the rheumatoid hand using 3D contrast-enhanced MRI and shuffle transform.

Pre- and postoperative radiotherapy for extremity soft tissue sarcoma: Evaluation of inter-observer target volume contouring variability among French sarcoma group radiation oncologists.

PubMed

Sargos, P; Charleux, T; Haas, R L; Michot, A; Llacer, C; Moureau-Zabotto, L; Vogin, G; Le Péchoux, C; Verry, C; Ducassou, A; Delannes, M; Mervoyer, A; Wiazzane, N; Thariat, J; Sunyach, M P; Benchalal, M; Laredo, J D; Kind, M; Gillon, P; Kantor, G

2018-04-01

The purpose of this study was to evaluate, during a national workshop, the inter-observer variability in target volume delineation for primary extremity soft tissue sarcoma radiation therapy. Six expert sarcoma radiation oncologists (members of French Sarcoma Group) received two extremity soft tissue sarcoma radiation therapy cases 1: one preoperative and one postoperative. They were distributed with instructions for contouring gross tumour volume or reconstructed gross tumour volume, clinical target volume and to propose a planning target volume. The preoperative radiation therapy case was a patient with a grade 1 extraskeletal myxoid chondrosarcoma of the thigh. The postoperative case was a patient with a grade 3 pleomorphic undifferentiated sarcoma of the thigh. Contour agreement analysis was performed using kappa statistics. For the preoperative case, contouring agreement regarding GTV, gross tumour volume GTV, clinical target volume and planning target volume were substantial (kappa between 0.68 and 0.77). In the postoperative case, the agreement was only fair for reconstructed gross tumour volume (kappa: 0.38) but moderate for clinical target volume and planning target volume (kappa: 0.42). During the workshop discussion, consensus was reached on most of the contour divergences especially clinical target volume longitudinal extension. The determination of a limited cutaneous cover was also discussed. Accurate delineation of target volume appears to be a crucial element to ensure multicenter clinical trial quality assessment, reproducibility and homogeneity in delivering RT. radiation therapy RT. Quality assessment process should be proposed in this setting. We have shown in our study that preoperative radiation therapy of extremity soft tissue sarcoma has less inter-observer contouring variability. Copyright © 2018 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

Wheat (Triticum aestivum L.) transformation using mature embryos.

PubMed

Medvecká, Eva; Harwood, Wendy A

2015-01-01

In most protocols for the Agrobacterium-mediated transformation of wheat, the preferred target tissues are immature embryos. However, transformation methods relying on immature embryos require the growth of plants under controlled conditions to provide a continuous supply of good-quality target tissue. The use of mature embryos as a target tissue has the advantage of only requiring good-quality seed as the starting material. Here we describe a transformation method based on the Agrobacterium-mediated transformation of callus cultures derived from mature wheat embryos of the genotype Bobwhite S56.

Helicity is the only integral invariant of volume-preserving transformations

PubMed Central

Enciso, Alberto; Peralta-Salas, Daniel; de Lizaur, Francisco Torres

2016-01-01

We prove that any regular integral invariant of volume-preserving transformations is equivalent to the helicity. Specifically, given a functional ℐ defined on exact divergence-free vector fields of class C1 on a compact 3-manifold that is associated with a well-behaved integral kernel, we prove that ℐ is invariant under arbitrary volume-preserving diffeomorphisms if and only if it is a function of the helicity. PMID:26864201

Control theory based airfoil design for potential flow and a finite volume discretization

NASA Technical Reports Server (NTRS)

Reuther, J.; Jameson, A.

1994-01-01

This paper describes the implementation of optimization techniques based on control theory for airfoil design. In previous studies it was shown that control theory could be used to devise an effective optimization procedure for two-dimensional profiles in which the shape is determined by a conformal transformation from a unit circle, and the control is the mapping function. The goal of our present work is to develop a method which does not depend on conformal mapping, so that it can be extended to treat three-dimensional problems. Therefore, we have developed a method which can address arbitrary geometric shapes through the use of a finite volume method to discretize the potential flow equation. Here the control law serves to provide computationally inexpensive gradient information to a standard numerical optimization method. Results are presented, where both target speed distributions and minimum drag are used as objective functions.

Activin-A, transforming growth factor-beta, and myostatin signaling pathway in experimental dilated cardiomyopathy.

PubMed

Mahmoudabady, Maryam; Mathieu, Myrielle; Dewachter, Laurence; Hadad, Ielham; Ray, Lynn; Jespers, Pascale; Brimioulle, Serge; Naeije, Robert; McEntee, Kathleen

2008-10-01

The pathogenic mechanisms of dilated cardiomyopathy are still uncertain. A number of cytokines and growth factors participate in the remodeling process of the disease. We investigated the cardiac myostatin, transforming growth factor (TGF)beta, and activin-A/Smad growth inhibitory signaling pathway in experimental dilated cardiomyopathy. Transvenous endomyocardial biopsies of the interventricular septum were taken weekly in 15 beagle dogs during the development of heart failure (HF) induced by rapid pacing over a period of 7 weeks. Genes involved in the myostatin-TGFbeta-activin-A/Smad signaling pathway and the cardiac hypertrophic process were quantified by real-time quantitative polymerase chain reaction. Left ventricular volume, function, and mass were evaluated by echocardiography. Overpacing was associated with increased left ventricular volumes and decreased ejection fraction, whereas the left ventricular mass remained unchanged. TGFbeta was increased in moderate HF. Activin-A mRNA expression was 4-fold higher in overt congestive HF than at baseline. A 2-fold decrease of activin type II receptors and activin receptor interacting protein 2 gene expressions were observed, as well as a transient decrease of follistatin. Activin type I receptors, activin receptor interacting protein 1, follistatin-related gene, and myostatin remained unchanged. The inhibitory Smad 7, a negative feedback loop regulator of the Smad pathway, was overexpressed in severe HF. Gene expression of the cyclin-dependent kinase inhibitor p21, a direct target gene of the Smad pathway, was 8-fold up-regulated in HF, whereas cyclin D1 was down-regulated. We conclude that tachycardia-induced dilated cardiomyopathy is characterized by gene overexpression of the TGFbeta-activin-A/Smad signaling pathway and their target gene p21 and by the absence of ventricular hypertrophy.

Smart grid initialization reduces the computational complexity of multi-objective image registration based on a dual-dynamic transformation model to account for large anatomical differences

NASA Astrophysics Data System (ADS)

Bosman, Peter A. N.; Alderliesten, Tanja

2016-03-01

We recently demonstrated the strong potential of using dual-dynamic transformation models when tackling deformable image registration problems involving large anatomical differences. Dual-dynamic transformation models employ two moving grids instead of the common single moving grid for the target image (and single fixed grid for the source image). We previously employed powerful optimization algorithms to make use of the additional flexibility offered by a dual-dynamic transformation model with good results, directly obtaining insight into the trade-off between important registration objectives as a result of taking a multi-objective approach to optimization. However, optimization has so far been initialized using two regular grids, which still leaves a great potential of dual-dynamic transformation models untapped: a-priori grid alignment with image structures/areas that are expected to deform more. This allows (far) less grid points to be used, compared to using a sufficiently refined regular grid, leading to (far) more efficient optimization, or, equivalently, more accurate results using the same number of grid points. We study the implications of exploiting this potential by experimenting with two new smart grid initialization procedures: one manual expert-based and one automated image-feature-based. We consider a CT test case with large differences in bladder volume with and without a multi-resolution scheme and find a substantial benefit of using smart grid initialization.

Tensor Fukunaga-Koontz transform for small target detection in infrared images

NASA Astrophysics Data System (ADS)

Liu, Ruiming; Wang, Jingzhuo; Yang, Huizhen; Gong, Chenglong; Zhou, Yuanshen; Liu, Lipeng; Zhang, Zhen; Shen, Shuli

2016-09-01

Infrared small targets detection plays a crucial role in warning and tracking systems. Some novel methods based on pattern recognition technology catch much attention from researchers. However, those classic methods must reshape images into vectors with the high dimensionality. Moreover, vectorizing breaks the natural structure and correlations in the image data. Image representation based on tensor treats images as matrices and can hold the natural structure and correlation information. So tensor algorithms have better classification performance than vector algorithms. Fukunaga-Koontz transform is one of classification algorithms and it is a vector version method with the disadvantage of all vector algorithms. In this paper, we first extended the Fukunaga-Koontz transform into its tensor version, tensor Fukunaga-Koontz transform. Then we designed a method based on tensor Fukunaga-Koontz transform for detecting targets and used it to detect small targets in infrared images. The experimental results, comparison through signal-to-clutter, signal-to-clutter gain and background suppression factor, have validated the advantage of the target detection based on the tensor Fukunaga-Koontz transform over that based on the Fukunaga-Koontz transform.

The transformation of targeted killing and international order

PubMed Central

Senn, Martin; Troy, Jodok

2017-01-01

ABSTRACT This article introduces the special issue’s question of whether and how the current transformation of targeted killing is transforming the global international order and provides the conceptual ground for the individual contributions to the special issue. It develops a two-dimensional concept of political order and introduces a theoretical framework that conceives the maintenance and transformation of international order as a dynamic interplay between its behavioral dimension in the form of violence and discursive processes and its institutional dimension in the form of ideas, norms, and rules. The article also conceptualizes targeted killing and introduces a typology of targeted-killing acts on the basis of their legal and moral legitimacy. Building on this conceptual groundwork, the article takes stock of the current transformation of targeted killing and summarizes the individual contributions to this special issue. PMID:29097903

DOE Office of Scientific and Technical Information (OSTI.GOV)

Devaraj, Arun; Jana, Saumyadeep; McInnis, Colleen A.

During eutectoid transformation of U-10Mo alloy, uniform metastable γ UMo phase is expected to transform to a mixture of α-U and γ’-U 2Mo phase. The presence of transformation products in final U-10Mo fuel, especially the α phase is considered detrimental for fuel irradiation performance, so it is critical to accurately evaluate the extent of transformation in the final U-10Mo alloy. This phase transformation can cause a volume change that induces a density change in final alloy. To understand this density and volume change, we developed a theoretical model to calculate the volume expansion and resultant density change of U-10Mo alloymore » as a function of the extent of eutectoid transformation. Based on the theoretically calculated density change for 0 to 100% transformation, we conclude that an experimental density measurement system will be challenging to employ to reliably detect and quantify the extent of transformation. Subsequently, to assess the ability of various methods to detect the transformation in U-10Mo, we annealed U-10Mo alloy samples at 500°C for various times to achieve in low, medium, and high extent of transformation. After the heat treatment at 500°C, the samples were metallographically polished and subjected to optical microscopy and x-ray diffraction (XRD) methods. Based on our assessment, optical microscopy and image processing can be used to determine the transformed area fraction, which can then be correlated with the α phase volume fraction measured by XRD analysis. XRD analysis of U-10Mo aged at 500°C detected only α phase and no γ’ was detected. To further validate the XRD results, atom probe tomography (APT) was used to understand the composition of transformed regions in U-10Mo alloys aged at 500°C for 10 hours. Based on the APT results, the lamellar transformation product was found to comprise α phase with close to 0 at% Mo and γ phase with 28–32 at% Mo, and the Mo concentration was highest at the α/γ interface.« less

Missing texture reconstruction method based on error reduction algorithm using Fourier transform magnitude estimation scheme.

PubMed

Ogawa, Takahiro; Haseyama, Miki

2013-03-01

A missing texture reconstruction method based on an error reduction (ER) algorithm, including a novel estimation scheme of Fourier transform magnitudes is presented in this brief. In our method, Fourier transform magnitude is estimated for a target patch including missing areas, and the missing intensities are estimated by retrieving its phase based on the ER algorithm. Specifically, by monitoring errors converged in the ER algorithm, known patches whose Fourier transform magnitudes are similar to that of the target patch are selected from the target image. In the second approach, the Fourier transform magnitude of the target patch is estimated from those of the selected known patches and their corresponding errors. Consequently, by using the ER algorithm, we can estimate both the Fourier transform magnitudes and phases to reconstruct the missing areas.

Effect of volume fraction of alpha and transformed beta on the high cycle fatigue properties of bimodal Ti6Al4V alloy

NASA Astrophysics Data System (ADS)

Jadhav, Shital; Powar, Amit; Patil, Sandip; Supare, Ashish; Farane, Bhagwan; Singh, Rajkumar, Dr.

2017-05-01

The present study was performed to investigate the effect of volume fraction of alpha and transformed beta phase on the high-cycle fatigue (HCF) properties of the bimodal titanium Ti6Al4V alloy. The effect of such morphology on mechanical properties was studied using tensile and rotating bending fatigue test as per ASTM standards. Microstructures and fractography of the specimens were studied using optical and scanning electron microscopy (SEM) respectively.Ti6Al4V alloy samples were heat treated to have three distinctive volume fractions of alpha and transformed beta phase. With an increase in quench delay from 30,50 and 70 sec during quenching after solutionizing temperature of 967°C, the volume fraction of alpha was found to be increased from 20% to 67%. Tests on tensile and rotating bending fatigue showed that the specimen with 20% volume fraction of alpha phase exhibited the highest tensile and fatigue strength, however the properties gets deteriorate with increase in volume fraction of alpha.

Detection of Fast Moving and Accelerating Targets Compensating Range and Doppler Migration

DTIC Science & Technology

2014-06-01

Radon -Fourier transform has been introduced to realize long- term coherent integration of the moving targets with range migration [8, 9]. Radon ...2010) Long-time coherent integration for radar target detection base on Radon -Fourier transform, in Proceedings of the IEEE Radar Conference, pp...432–436. 9. Xu, J., Yu, J., Peng, Y. & Xia, X. (2011) Radon -Fourier transform for radar target detection, I: Generalized Doppler filter bank, IEEE

The use of biomarkers to describe plasma-, red cell-, and blood volume from a simple blood test.

PubMed

Lobigs, Louisa Margit; Sottas, Pierre-Edouard; Bourdon, Pitre Collier; Nikolovski, Zoran; El-Gingo, Mohamed; Varamenti, Evdokia; Peeling, Peter; Dawson, Brian; Schumacher, Yorck Olaf

2017-01-01

Plasma volume and red cell mass are key health markers used to monitor numerous disease states, such as heart failure, kidney disease, or sepsis. Nevertheless, there is currently no practically applicable method to easily measure absolute plasma or red cell volumes in a clinical setting. Here, a novel marker for plasma volume and red cell mass was developed through analysis of the observed variability caused by plasma volume shifts in common biochemical measures, selected based on their propensity to present with low variations over time. Once a month for 6 months, serum and whole blood samples were collected from 33 active males. Concurrently, the CO-rebreathing method was applied to determine target levels of hemoglobin mass (HbM) and blood volumes. The variability of 18 common chemistry markers and 27 Full Blood Count variables was investigated and matched to the observed plasma volume variation. After the removal of between-subject variations using a Bayesian model, multivariate analysis identified two sets of 8 and 15 biomarkers explaining 68% and 69% of plasma volume variance, respectively. The final multiparametric model contains a weighting function to allow for isolated abnormalities in single biomarkers. This proof-of-concept investigation describes a novel approach to estimate absolute vascular volumes, with a simple blood test. Despite the physiological instability of critically ill patients, it is hypothesized the model, with its multiparametric approach and weighting function, maintains the capacity to describe vascular volumes. This model has potential to transform volume management in clinical settings. Am. J. Hematol. 92:62-67, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Kinetic effects on the morphology and stability of the pressure-induced extended-solid of carbon monoxide

NASA Astrophysics Data System (ADS)

Dang, Nhan C.; Ciezak-Jenkins, Jennifer A.

2018-04-01

In this work, the dependence of the morphology and stability of the extended solid of carbon monoxide (CO) is correlated to the rate of transformation from the molecular CO to extended solid of CO using optical imaging, photoluminescence, Raman spectroscopy, and X-ray diffraction. The analyses show the rate and pressure of the transformation to be strongly controlled by catalytic effects, both chemical and optical. In a larger volume per reaction area, the transformation was found to require either a longer time at an elevated pressure or a higher pressure compared to a sample synthesized in a smaller volume per reaction area, leading to the conclusion that the transformation rate is slower for a sample in a larger volume per reaction area. A faster rate of transformation was also noted when the reaction area of a CO sample was catalyzed with H2SO4. Through variation of the volume per reaction area, pressure or the addition of catalysts, it was possible to control the rate of the phase transition and therefore the morphology. In general, the extended solid of CO synthesized with a faster rate showed a more ordered structure and increased metastability relative to the material formed with a slower compression rate.

On framing potential features of SWCNTs and MWCNTs in mixed convective flow

NASA Astrophysics Data System (ADS)

Hayat, T.; Ullah, Siraj; Khan, M. Ijaz; Alsaedi, A.

2018-03-01

Our target in this research article is to elaborate the characteristics of Darcy-Forchheimer relation in carbon-water nanoliquid flow induced by impermeable stretched cylinder. Energy expression is modeled through viscous dissipation and nonlinear thermal radiation. Application of appropriate transformations yields nonlinear ODEs through nonlinear PDEs. Shooting technique is adopted for the computations of nonlinear ODEs. Importance of influential variables for velocity and thermal fields is elaborated graphically. Moreover rate of heat transfer and drag force are calculated and demonstrated through Tables. Our analysis reports that velocity is higher for ratio of rate constant and buoyancy factor when compared with porosity and volume fraction.

Genetic transformation protocols using zygotic embryos as explants: an overview.

PubMed

Tahir, Muhammad; Waraich, Ejaz A; Stasolla, Claudio

2011-01-01

Genetic transformation of plants is an innovative research tool which has practical significance for the development of new and improved genotypes or cultivars. However, stable introduction of genes of interest into nuclear genomes depends on several factors such as the choice of target tissue, the method of DNA delivery in the target tissue, and the appropriate method to select the transformed plants. Mature or immature zygotic embryos have been a popular choice as explant or target tissue for genetic transformation in both angiosperms and gymnosperms. As a result, considerable protocols have emerged in the literature which have been optimized for various plant species in terms of transformation methods and selection procedures for transformed plants. This article summarizes the recent advances in plant transformation using zygotic embryos as explants.

Effect of lattice-mismatch-induced strains on coupled diffusive and displacive phase transformations

NASA Astrophysics Data System (ADS)

Bouville, Mathieu; Ahluwalia, Rajeev

2007-02-01

Materials which can undergo slow diffusive transformations as well as fast displacive transformations are studied using the phase-field method. The model captures the essential features of the time-temperature-transformation (TTT) diagrams, continuous cooling transformation (CCT) diagrams, and microstructure formation of these alloys. In some material systems there can exist an intrinsic volume change associated with these transformations. We show that these coherency strains can stabilize mixed microstructures (such as retained austenite-martensite and pearlite-martensite mixtures) by an interplay between diffusive and displacive mechanisms, which can alter TTT and CCT diagrams. Depending on the conditions there can be competitive or cooperative nucleation of the two kinds of phases. The model also shows that small differences in volume changes can have noticeable effects on the early stages of martensite formation and on the resulting microstructures.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Katsuta, Y; Tohoku University Graduate School of Medicine, Sendal, Miyagi; Kadoya, N

Purpose: In this study, we developed a system to calculate three dimensional (3D) dose that reflects dosimetric error caused by leaf miscalibration for head and neck and prostate volumetric modulated arc therapy (VMAT) without additional treatment planning system calculation on real time. Methods: An original system called clarkson dose calculation based dosimetric error calculation to calculate dosimetric error caused by leaf miscalibration was developed by MATLAB (Math Works, Natick, MA). Our program, first, calculates point doses at isocenter for baseline and modified VMAT plan, which generated by inducing MLC errors that enlarged aperture size of 1.0 mm with clarkson dosemore » calculation. Second, error incuced 3D dose was generated with transforming TPS baseline 3D dose using calculated point doses. Results: Mean computing time was less than 5 seconds. For seven head and neck and prostate plans, between our method and TPS calculated error incuced 3D dose, the 3D gamma passing rates (0.5%/2 mm, global) are 97.6±0.6% and 98.0±0.4%. The dose percentage change with dose volume histogram parameter of mean dose on target volume were 0.1±0.5% and 0.4±0.3%, and with generalized equivalent uniform dose on target volume were −0.2±0.5% and 0.2±0.3%. Conclusion: The erroneous 3D dose calculated by our method is useful to check dosimetric error caused by leaf miscalibration before pre treatment patient QA dosimetry checks.« less

Transforming Education: Global Perspectives, Experiences and Implications. Educational Psychology: Critical Pedagogical Perspectives. Volume 24

ERIC Educational Resources Information Center

DeVillar, Robert A., Ed.; Jiang, Binbin, Ed.; Cummins, Jim, Ed.

2013-01-01

This research-based volume presents a substantive, panoramic view of ways in which Australia and countries in Africa, Asia, Europe, and North and South America engage in educational programs and practices to transform the learning processes and outcomes of their students. It reveals and analyzes national and global trajectories in key areas of…

Geometric shapes inversion method of space targets by ISAR image segmentation

NASA Astrophysics Data System (ADS)

Huo, Chao-ying; Xing, Xiao-yu; Yin, Hong-cheng; Li, Chen-guang; Zeng, Xiang-yun; Xu, Gao-gui

2017-11-01

The geometric shape of target is an effective characteristic in the process of space targets recognition. This paper proposed a method of shape inversion of space target based on components segmentation from ISAR image. The Radon transformation, Hough transformation, K-means clustering, triangulation will be introduced into ISAR image processing. Firstly, we use Radon transformation and edge detection to extract space target's main body spindle and solar panel spindle from ISAR image. Then the targets' main body, solar panel, rectangular and circular antenna are segmented from ISAR image based on image detection theory. Finally, the sizes of every structural component are computed. The effectiveness of this method is verified using typical targets' simulation data.

Improving the consistency in cervical esophageal target volume definition by special training.

PubMed

Tai, Patricia; Van Dyk, Jake; Battista, Jerry; Yu, Edward; Stitt, Larry; Tonita, Jon; Agboola, Olusegun; Brierley, James; Dar, Rashid; Leighton, Christopher; Malone, Shawn; Strang, Barbara; Truong, Pauline; Videtic, Gregory; Wong, C Shun; Wong, Rebecca; Youssef, Youssef

2002-07-01

Three-dimensional conformal radiation therapy requires the precise definition of the target volume. Its potential benefits could be offset by the inconsistency in target definition by radiation oncologists. In a previous survey of radiation oncologists, a large degree of variation in target volume definition of cervical esophageal cancer was noted for the boost phase of radiotherapy. The present study evaluated whether special training could improve the consistency in target volume definitions. A pre-training survey was performed to establish baseline values. This was followed by a special one-on-one training session on treatment planning based on the RTOG 94-05 protocol to 12 radiation oncologists. Target volumes were redrawn immediately and at 1-2 months later. Post-training vs. pre-training target volumes were compared. There was less variability in the longitudinal positions of the target volumes post-training compared to pre-training (p < 0.05 in 5 of 6 comparisons). One case had more variability due to the lack of a visible gross tumor on CT scans. Transverse contours of target volumes did not show any significant difference pre- or post-training. For cervical esophageal cancer, this study suggests that special training on protocol guidelines may improve consistency in target volume definition. Explicit protocol directions are required for situations where the gross tumor is not easily visible on CT scans. This may be particularly important for multicenter clinical trials, to reduce the occurrences of protocol violations.

OPS MCC level B/C formulation requirements: Area targets and space volumes processor

NASA Technical Reports Server (NTRS)

Bishop, M. J., Jr.

1979-01-01

The level B/C mathematical specifications for the area targets and space volumes processor (ATSVP) are described. The processor is designed to compute the acquisition-of-signal (AOS) and loss-of-signal (LOS) times for area targets and space volumes. The characteristics of the area targets and space volumes are given. The mathematical equations necessary to determine whether the spacecraft lies within the area target or space volume are given. These equations provide a detailed model of the target geometry. A semianalytical technique for predicting the AOS and LOS time periods is disucssed. This technique was designed to bound the actual visibility period using a simplified target geometry model and unperturbed orbital motion. Functional overview of the ATSVP is presented and it's detailed logic flow is described.

Time history solution program, L225 (TEV126). Volume 1: Engineering and usage

NASA Technical Reports Server (NTRS)

Kroll, R. I.; Tornallyay, A.; Clemmons, R. E.

1979-01-01

Volume 1 of a two volume document is presented. The usage of the convolution program L225 (TEV 126) is described. The program calculates the time response of a linear system by convoluting the impulsive response function with the time-dependent excitation function. The convolution is performed as a multiplication in the frequency domain. Fast Fourier transform techniques are used to transform the product back into the time domain to obtain response time histories. A brief description of the analysis used is presented.

Damping behavior of polymer composites with high volume fraction of NiMnGa powders

NASA Astrophysics Data System (ADS)

Sun, Xiaogang; Song, Jie; Jiang, Hong; Zhang, Xiaoning; Xie, Chaoying

2011-03-01

Polymer composites inserted with high volume fraction (up to 70 Vol%) of NiMnGa powders were fabricated and their damping behavior was investigated by dynamic mechanical analysis. It is found that the polymer matrix has little influence on the transformation temperatures of NiMnGa powders. A damping peak appears for NiMnGa/epoxy resin (EP) composites accompanying with the martensitic transformation or reverse martensitic transformation of NiMnGa powders during cooling or heating. The damping capacity for NiMnGa/EP composites increases linearly with the increase of volume fraction of NiMnGa powders and, decreases dramatically as the test frequency increases. The fracture strain of NiMnGa/EP composites decrease with the increase of NiMnGa powders.

Determination of the continuous cooling transformation diagram of a high strength low alloyed steel

NASA Astrophysics Data System (ADS)

Kang, Hun Chul; Park, Bong June; Jang, Ji Hun; Jang, Kwang Soon; Lee, Kyung Jong

2016-11-01

The continuous cooling transformation diagram of a high strength low alloyed steel was determined by a dilatometer and microscopic analysis (OM, SEM) as well as thermodynamic analysis. As expected, Widmanstätten ferrite, bainite and martensite coexisted for most cooling rates, which made it difficult to determine the transformation kinetics of individual phases. However, peaks were clearly observed in the dilatometric {d( {LVDT} )}/{dT} curves. By overlapping the {d( {LVDT} )}/{dT} curves, which were determined using various cooling rates, peaks were separated and the peak rate temperatures, as well as the temperature at the start of transformation (5%) and the end of transformation (95%) of an individual phase, were determined. A SEM analysis was also conducted to identify which phase existed and to quantify the volume fraction of each phase. It was confirmed that the additional {d( {LVDT} )}/{dT} curve analysis described the transformation behavior more precisely than the conventional continuous cooling transformation diagram, as determined by the volume measured from the microstructure analysis.

Automatic selection of landmarks in T1-weighted head MRI with regression forests for image registration initialization

NASA Astrophysics Data System (ADS)

Wang, Jianing; Liu, Yuan; Noble, Jack H.; Dawant, Benoit M.

2017-02-01

Medical image registration establishes a correspondence between images of biological structures and it is at the core of many applications. Commonly used deformable image registration methods are dependent on a good preregistration initialization. The initialization can be performed by localizing homologous landmarks and calculating a point-based transformation between the images. The selection of landmarks is however important. In this work, we present a learning-based method to automatically find a set of robust landmarks in 3D MR image volumes of the head to initialize non-rigid transformations. To validate our method, these selected landmarks are localized in unknown image volumes and they are used to compute a smoothing thin-plate splines transformation that registers the atlas to the volumes. The transformed atlas image is then used as the preregistration initialization of an intensity-based non-rigid registration algorithm. We show that the registration accuracy of this algorithm is statistically significantly improved when using the presented registration initialization over a standard intensity-based affine registration.

3D Registration of mpMRI for Assessment of Prostate Cancer Focal Therapy.

PubMed

Orczyk, Clément; Rosenkrantz, Andrew B; Mikheev, Artem; Villers, Arnauld; Bernaudin, Myriam; Taneja, Samir S; Valable, Samuel; Rusinek, Henry

2017-12-01

This study aimed to assess a novel method of three-dimensional (3D) co-registration of prostate magnetic resonance imaging (MRI) examinations performed before and after prostate cancer focal therapy. We developed a software platform for automatic 3D deformable co-registration of prostate MRI at different time points and applied this method to 10 patients who underwent focal ablative therapy. MRI examinations were performed preoperatively, as well as 1 week and 6 months post treatment. Rigid registration served as reference for assessing co-registration accuracy and precision. Segmentation of preoperative and postoperative prostate revealed a significant postoperative volume decrease of the gland that averaged 6.49 cc (P = .017). Applying deformable transformation based on mutual information from 120 pairs of MRI slices, we refined by 2.9 mm (max. 6.25 mm) the alignment of the ablation zone, segmented from contrast-enhanced images on the 1-week postoperative examination, to the 6-month postoperative T2-weighted images. This represented a 500% improvement over the rigid approach (P = .001), corrected by volume. The dissimilarity by Dice index of the mapped ablation zone using deformable transformation vs rigid control was significantly (P = .04) higher at the ablation site than in the whole gland. Our findings illustrate our method's ability to correct for deformation at the ablation site. The preliminary analysis suggests that deformable transformation computed from mutual information of preoperative and follow-up MRI is accurate in co-registration of MRI examinations performed before and after focal therapy. The ability to localize the previously ablated tissue in 3D space may improve targeting for image-guided follow-up biopsy within focal therapy protocols. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

Transformations: Proceedings of the 2008 Annual International Conference of the Association of Tertiary Learning Advisors of Aotearoa/New Zealand (ATLAANZ) (Porirua, New Zealand, November 19-21, 2008). Volume 4

ERIC Educational Resources Information Center

Silvester, Mary, Ed.

2009-01-01

This volume comprises the refereed proceedings of the 2008 ATLAANZ (Association of Tertiary Learning Advisors of Aotearoa/New Zealand) conference, and explores strands of transformations--learning within cultural contexts, service delivery, student literacy and numeracy, graduate students and professional practice. In Chapter 1, Kay Hammond…

Potential complications when developing gene deletion clones in Xylella fastidiosa.

PubMed

Johnson, Kameka L; Cursino, Luciana; Athinuwat, Dusit; Burr, Thomas J; Mowery, Patricia

2015-04-16

The Gram-negative xylem-limited bacterium, Xylella fastidiosa, is an important plant pathogen that infects a number of high value crops. The Temecula 1 strain infects grapevines and induces Pierce's disease, which causes symptoms such as scorching on leaves, cluster collapse, and eventual plant death. In order to understand the pathogenesis of X. fastidiosa, researchers routinely perform gene deletion studies and select mutants via antibiotic markers. Site-directed pilJ mutant of X. fastidiosa were generated and selected on antibiotic media. Mutant cultures were assessed by PCR to determine if they were composed of purely transformant cells or included mixtures of non-transformants cells. Then pure pilJ mutant and wildtype cells were mixed in PD2 medium and following incubation and exposure to kanamycin were assessed by PCR for presence of mutant and wildtype populations. We have discovered that when creating clones of targeted mutants of X. fastidiosa Temecula 1 with selection on antibiotic plates, X. fastidiosa lacking the gene deletion often persist in association with targeted mutant cells. We believe this phenomenon is due to spontaneous antibiotic resistance and/or X. fastidiosa characteristically forming aggregates that can be comprised of transformed and non-transformed cells. A combined population was confirmed by PCR, which showed that targeted mutant clones were mixed with non-transformed cells. After repeated transfer and storage the non-transformed cells became the dominant clone present. We have discovered that special precautions are warranted when developing a targeted gene mutation in X. fastidiosa because colonies that arise following transformation and selection are often comprised of transformed and non-transformed cells. Following transfer and storage the cells can consist primarily of the non-transformed strain. As a result, careful monitoring of targeted mutant strains must be performed to avoid mixed populations and confounding results.

Planned Subtotal Resection of Vestibular Schwannoma Differs from the Ideal Radiosurgical Target Defined by Adaptive Hybrid Surgery.

PubMed

Sheppard, John P; Lagman, Carlito; Prashant, Giyarpuram N; Alkhalid, Yasmine; Nguyen, Thien; Duong, Courtney; Udawatta, Methma; Gaonkar, Bilwaj; Tenn, Stephen E; Bloch, Orin; Yang, Isaac

2018-06-01

To retrospectively compare ideal radiosurgical target volumes defined by a manual method (surgeon) to those determined by Adaptive Hybrid Surgery (AHS) operative planning software in 7 patients with vestibular schwannoma (VS). Four attending surgeons (3 neurosurgeons and 1 ear, nose, and throat surgeon) manually contoured planned residual tumors volumes for 7 consecutive patients with VS. Next, the AHS software determined the ideal radiosurgical target volumes based on a specified radiotherapy plan. Our primary measure was the difference between the average planned residual tumor volumes and the ideal radiosurgical target volumes defined by AHS (dRV AHS-planned ). We included 7 consecutive patients with VS in this study. The planned residual tumor volumes were smaller than the ideal radiosurgical target volumes defined by AHS (1.6 vs. 4.5 cm 3 , P = 0.004). On average, the actual post-operative residual tumor volumes were smaller than the ideal radiosurgical target volumes defined by AHS (2.2 cm 3 vs. 4.5 cm 3 ; P = 0.02). The average difference between the ideal radiosurgical target volume defined by AHS and the planned residual tumor volume (dRV AHS-planned ) was 2.9 ± 1.7 cm 3 , and we observed a trend toward larger dRV AHS-planned in patients who lost serviceable facial nerve function compared with patients who maintained serviceable facial nerve function (4.7 cm 3 vs. 1.9 cm 3 ; P = 0.06). Planned subtotal resection of VS diverges from the ideal radiosurgical target defined by AHS, but whether that influences clinical outcomes is unclear. Copyright © 2018 Elsevier Inc. All rights reserved.

Synergistic Effects among the Structure, Martensite Transformation and Shear Band in a Shape Memory Alloy-Metallic Glass Composite

NASA Astrophysics Data System (ADS)

Zhang, Xudong; Ren, Junqiang; Ding, Xiangdong

2018-05-01

In this work, we use the finite element method to investigate the free volume evolution, as well as the martensite transformation effect and its connection with the pretreatment strain, in a shape memory alloy-metallic glass composite. Our simulation results show that the martensite phase transformation can enhance the blocking effect while relieving the free volume localization. The synergistic effect among the martensite transformation effect, blocking effect, and shear band interaction in the composite is responsible for the tensile plasticity and work-hardening capability. In addition, we design a Sierpinski carpet-like fractal microstructure so that the composite exhibits improved tensile performance as a result of the enhanced synergistic effect. However, the tensile performance of the composite deteriorates with increasing pretreatment strain since the martensite transformation effect is weakened.

Warping of a computerized 3-D atlas to match brain image volumes for quantitative neuroanatomical and functional analysis

NASA Astrophysics Data System (ADS)

Evans, Alan C.; Dai, Weiqian; Collins, D. Louis; Neelin, Peter; Marrett, Sean

1991-06-01

We describe the implementation, experience and preliminary results obtained with a 3-D computerized brain atlas for topographical and functional analysis of brain sub-regions. A volume-of-interest (VOI) atlas was produced by manual contouring on 64 adjacent 2 mm-thick MRI slices to yield 60 brain structures in each hemisphere which could be adjusted, originally by global affine transformation or local interactive adjustments, to match individual MRI datasets. We have now added a non-linear deformation (warp) capability (Bookstein, 1989) into the procedure for fitting the atlas to the brain data. Specific target points are identified in both atlas and MRI spaces which define a continuous 3-D warp transformation that maps the atlas on to the individual brain image. The procedure was used to fit MRI brain image volumes from 16 young normal volunteers. Regional volume and positional variability were determined, the latter in such a way as to assess the extent to which previous linear models of brain anatomical variability fail to account for the true variation among normal individuals. Using a linear model for atlas deformation yielded 3-D fits of the MRI data which, when pooled across subjects and brain regions, left a residual mis-match of 6 - 7 mm as compared to the non-linear model. The results indicate a substantial component of morphometric variability is not accounted for by linear scaling. This has profound implications for applications which employ stereotactic coordinate systems which map individual brains into a common reference frame: quantitative neuroradiology, stereotactic neurosurgery and cognitive mapping of normal brain function with PET. In the latter case, the combination of a non-linear deformation algorithm would allow for accurate measurement of individual anatomic variations and the inclusion of such variations in inter-subject averaging methodologies used for cognitive mapping with PET.

Volume and Mass Estimation of Three-Phase High Power Transformers for Space Applications

NASA Technical Reports Server (NTRS)

Kimnach, Greg L.

2004-01-01

Spacecraft historically have had sub-1kW(sub e), electrical requirements for GN&C, science, and communications: Galileo at 600W(sub e), and Cassini at 900W(sub e), for example. Because most missions have had the same order of magnitude power requirements, the Power Distribution Systems (PDS) use existing, space-qualified technology and are DC. As science payload and mission duration requirements increase, however, the required electrical power increases. Subsequently, this requires a change from a passive energy conversion (solar arrays and batteries) to dynamic (alternator, solar dynamic, etc.), because dynamic conversion has higher thermal and conversion efficiencies, has higher power densities, and scales more readily to higher power levels. Furthermore, increased power requirements and physical distribution lengths are best served with high-voltage, multi-phase AC to maintain distribution efficiency and minimize voltage drops. The generated AC-voltage must be stepped-up (or down) to interface with various subsystems or electrical hardware. Part of the trade-space design for AC distribution systems is volume and mass estimation of high-power transformers. The volume and mass are functions of the power rating, operating frequency, the ambient and allowable temperature rise, the types and amount of heat transfer available, the core material and shape, the required flux density in a core, the maximum current density, etc. McLyman has tabulated the performance of a number of transformers cores and derived a "cookbook" methodology to determine the volume of transformers, whereas Schawrze had derived an empirical method to estimate the mass of single-phase transformers. Based on the work of McLyman and Schwarze, it is the intent herein to derive an empirical solution to the volume and mass estimation of three-phase, laminated EI-core power transformers, having radiated and conducted heat transfer mechanisms available. Estimation of the mounting hardware, connectors, etc. is not included.

A comparison of Agrobacterium-mediated transformation and protoplast-mediated transformation with CRISPR-Cas9 and bipartite gene targeting substrates, as effective gene targeting tools for Aspergillus carbonarius.

PubMed

Weyda, István; Yang, Lei; Vang, Jesper; Ahring, Birgitte K; Lübeck, Mette; Lübeck, Peter S

2017-04-01

In recent years, versatile genetic tools have been developed and applied to a number of filamentous fungi of industrial importance. However, the existing techniques have limitations when it comes to achieve the desired genetic modifications, especially for efficient gene targeting. In this study, we used Aspergillus carbonarius as a host strain due to its potential as a cell factory, and compared three gene targeting techniques by disrupting the ayg1 gene involved in the biosynthesis of conidial pigment in A. carbonarius. The absence of the ayg1 gene leads to phenotypic change in conidia color, which facilitated the analysis on the gene targeting frequency. The examined transformation techniques included Agrobacterium-mediated transformation (AMT) and protoplast-mediated transformation (PMT). Furthermore, the PMT for the disruption of the ayg1 gene was carried out with bipartite gene targeting fragments and the recently adapted CRISPR-Cas9 system. All three techniques were successful in generating Δayg1 mutants, but showed different efficiencies. The most efficient method for gene targeting was AMT, but further it was shown to be dependent on the choice of Agrobacterium strain. However, there are different advantages and disadvantages of all three gene targeting methods which are discussed, in order to facilitate future approaches for fungal strain improvements. Copyright © 2017 Elsevier B.V. All rights reserved.

The DC dielectric breakdown strength of magnetic fluids based on transformer oil

NASA Astrophysics Data System (ADS)

Kopčanský, Peter; Tomčo, Ladislav; Marton, Karol; Koneracká, Martina; Timko, Milan; Potočová, Ivana

2005-03-01

The DC dielectric breakdown strength of magnetic fluids based on transformer oil TECHNOL US 4000, with different saturation magnetizations, was investigated in various orientations of external magnetic field. It was shown that the dielectric breakdown strength in H∣∣ E is strongly influenced by the aggregation effects. As a boundary volume concentration of magnetic particles, below which the magnetic fluids have better dielectric properties than pure transformer oil, the volume concentration Φ=0.01 was found. Thus magnetic fluids with Φ<0.01 are suitable for the use as a high-voltage insulation.

Truncated feature representation for automatic target detection using transformed data-based decomposition

NASA Astrophysics Data System (ADS)

Riasati, Vahid R.

2016-05-01

In this work, the data covariance matrix is diagonalized to provide an orthogonal bases set using the eigen vectors of the data. The eigen-vector decomposition of the data is transformed and filtered in the transform domain to truncate the data for robust features related to a specified set of targets. These truncated eigen features are then combined and reconstructed to utilize in a composite filter and consequently utilized for the automatic target detection of the same class of targets. The results associated with the testing of the current technique are evaluated using the peak-correlation and peak-correlation energy metrics and are presented in this work. The inverse transformed eigen-bases of the current technique may be thought of as an injected sparsity to minimize data in representing the skeletal data structure information associated with the set of targets under consideration.

Methods for genetic transformation of filamentous fungi.

PubMed

Li, Dandan; Tang, Yu; Lin, Jun; Cai, Weiwen

2017-10-03

Filamentous fungi have been of great interest because of their excellent ability as cell factories to manufacture useful products for human beings. The development of genetic transformation techniques is a precondition that enables scientists to target and modify genes efficiently and may reveal the function of target genes. The method to deliver foreign nucleic acid into cells is the sticking point for fungal genome modification. Up to date, there are some general methods of genetic transformation for fungi, including protoplast-mediated transformation, Agrobacterium-mediated transformation, electroporation, biolistic method and shock-wave-mediated transformation. This article reviews basic protocols and principles of these transformation methods, as well as their advantages and disadvantages.

A transformation method for deriving from a photograph, position and heading of a vehicle in a plane

NASA Technical Reports Server (NTRS)

Sleeper, R. K.; Smith, E. G.

1976-01-01

Equations have been derived that transform perspectively viewed planar surface coordinates, as seen in a photograph, into coordinates of the original plane surface. These transformation equations are developed in terms of nine geometric variables that define the photographic setup and are redefined in terms of eight parameters. The parameters are then treated as independent quantities that fully characterize the transformation and are expressed directly in terms of the four corner coordinates of a reference rectangle in the object plane and their coordinates as seen in a photograph. Vehicle position is determined by transforming the perspectively viewed coordinate position of a representative vehicle target into runway coordinates. Vehicle heading is determined from the runway coordinates of two vehicle target points. When the targets are elevated above the plane of the reference grid, the computation of the heading angle is unaffected; however, the computation of the target position may require adjustment of two parameters. Methods are given for adjusting the parameters for elevation and an example is included for both nonelevated and elevated target conditions.

Kinetics of the mechanochemical synthesis of alkaline-earth metal amides

NASA Astrophysics Data System (ADS)

Garroni, Sebastiano; Takacs, Laszlo; Leng, Haiyan; Delogu, Francesco

2014-07-01

A phenomenological framework is developed to model the kinetics of the formation of alkaline-earth metal amides by the ball milling induced reaction of their hydrides with gaseous ammonia. It is shown that the exponential character of the kinetic curves is modulated by the increase of the total volume of the powder inside the reactor due to the substantially larger molar volume of the products compared to the reactants. It is claimed that the volume of powder effectively processed during each collision connects the transformation rate to the physical and chemical processes underlying the mechanochemical transformations.

Automating the Transformational Development of Software. Volume 1.

DTIC Science & Technology

1983-03-01

DRACO system [Neighbors 80] uses meta-rules to derive information about which new transformations will be applicable after a particular transformation has...transformation over another. The new model, as Incorporated in a system called Glitter, explicitly represents transformation goals, methods, and selection...done anew for each new problem (compare this with Neighbor’s Draco system [Neighbors 80] which attempts to reuse domain analysis). o Is the user

Combined Synchrotron X-ray Diffraction and Digital Image Correlation Technique for Measurement of Austenite Transformation with Strain in TRIP-assisted Steels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Poling, Whitney A.; Savic, Vesna; Hector, Louis G.

2016-04-05

The strain-induced, diffusionless shear transformation of retained austenite to martensite during straining of transformation induced plasticity (TRIP) assisted steels increases strain hardening and delays necking and fracture leading to exceptional ductility and strength, which are attractive for automotive applications. A novel technique that provides the retained austenite volume fraction variation with strain in TRIP-assisted steels with improved precision is presented. Digital images of the gauge section of tensile specimens were first recorded up to selected plastic strains with a stereo digital image correlation (DIC) system. The austenite volume fraction was measured by synchrotron X-ray diffraction from small squares cut frommore » the gage section. Strain fields in the squares were then computed by localizing the strain measurement to the corresponding region of a given square during DIC post-processing of the images recorded during tensile testing. Results obtained for a QP980 steel are used to study the influence of initial volume fraction of austenite and the austenite transformation with strain on tensile mechanical behavior.« less

Detection technology of polarization target based on curvelet transform in turbid liquid

NASA Astrophysics Data System (ADS)

Zhang, Su; Duan, Jin; Fu, Qiang; Zhan, Juntong; Ma, Wanzhuo

2015-08-01

To suppress the interference of the target detecting in the turbid medium, a kind of polarization detection technology based on Curvelet transform was applied. This method firstly adjusts the angles of polarizing film to get the intensity images of the situations at 0°,60° and 120°, then deduces the images of Stokes vectors, degree of polarization (DOP) and polarization angle (PA) according to the Mueller matrix. At last the DOP and intensity images can be decomposed by Curvelet transform to realize the fusion of the high and low coefficients respectively, after the processed coefficients are reconstructed, the target which is easier to detect can be achieved. To prove this method, many targets in turbid medium have been detected by polarization method and fused their DOP and intensity images with Curvelet transform algorithm. As an example screws in moderate and high concentration liquid are presented respectively, from which we can see the unpolarized targets are less obvious in higher concentration liquid. When the DOP and intensity images are fused by Curvelet transform, the targets are emerged clearly out of the turbid medium, and the values of the quality evaluation parameters in clarity, degree of contract and spatial frequency are prominently enhanced comparing with the unpolarized images, which can show the feasibility of this method.

The 3-D unstructured mesh generation using local transformations

NASA Technical Reports Server (NTRS)

Barth, Timothy J.

1993-01-01

The topics are presented in viewgraph form and include the following: 3D combinatorial edge swapping; 3D incremental triangulation via local transformations; a new approach to multigrid for unstructured meshes; surface mesh generation using local transforms; volume triangulations; viscous mesh generation; and future directions.

Interoperability format translation and transformation between IFC architectural design file and simulation file formats

DOEpatents

Chao, Tian-Jy; Kim, Younghun

2015-02-03

Automatically translating a building architecture file format (Industry Foundation Class) to a simulation file, in one aspect, may extract data and metadata used by a target simulation tool from a building architecture file. Interoperability data objects may be created and the extracted data is stored in the interoperability data objects. A model translation procedure may be prepared to identify a mapping from a Model View Definition to a translation and transformation function. The extracted data may be transformed using the data stored in the interoperability data objects, an input Model View Definition template, and the translation and transformation function to convert the extracted data to correct geometric values needed for a target simulation file format used by the target simulation tool. The simulation file in the target simulation file format may be generated.

Using vertical Fourier transforms to invert potential-field data to magnetization or density models in the presence of topography

USGS Publications Warehouse

Phillips, Jeffrey

2014-01-01

A physical property inversion approach based on the use of 3D (or 2D) Fourier transforms to calculate the potential-field within a 3D (or 2D) volume from a known physical property distribution within the volume is described. Topographic surfaces and observations at arbitrary locations are easily accommodated. The limitations of the approach and applications to real data are considered.

Deformable medical image registration of pleural cavity for photodynamic therapy by using finite-element based method

NASA Astrophysics Data System (ADS)

Penjweini, Rozhin; Kim, Michele M.; Dimofte, Andrea; Finlay, Jarod C.; Zhu, Timothy C.

2016-03-01

When the pleural cavity is opened during the surgery portion of pleural photodynamic therapy (PDT) of malignant mesothelioma, the pleural volume will deform. This impacts the delivered dose when using highly conformal treatment techniques. To track the anatomical changes and contour the lung and chest cavity, an infrared camera-based navigation system (NDI) is used during PDT. In the same patient, a series of computed tomography (CT) scans of the lungs are also acquired before the surgery. The reconstructed three-dimensional contours from both NDI and CTs are imported into COMSOL Multiphysics software, where a finite element-based (FEM) deformable image registration is obtained. The CT contour is registered to the corresponding NDI contour by overlapping the center of masses and aligning their orientations. The NDI contour is considered as the reference contour, and the CT contour is used as the target one, which will be deformed. Deformed Geometry model is applied in COMSOL to obtain a deformed target contour. The distortion of the volume at X, Y and Z is mapped to illustrate the transformation of the target contour. The initial assessment shows that FEM-based image deformable registration can fuse images acquired by different modalities. It provides insights into the deformation of anatomical structures along X, Y and Z-axes. The deformed contour has good matches to the reference contour after the dynamic matching process. The resulting three-dimensional deformation map can be used to obtain the locations of other critical anatomic structures, e.g., heart, during surgery.

Phase-Transformation-Induced Extra Thermal Expansion Behavior of (SrxBa1-x)TiO3/Cu Composite.

PubMed

Sheng, Jie; Wang, Lidong; Li, Shouwei; Yin, Benke; Liu, Xiangli; Fei, Wei-Dong

2016-06-03

The properties of metal matrix composites (MMCs) can be optimized effectively through adjusting the type or the volume fraction of reinforcement. Generally, the coefficient of thermal expansion (CTE) of MMCs can be reduced by increasing the volume fraction of the reinforcement with lower CTE than metal matrix. However, it is great challenge to fabricate low CTE MMCs with low reinforcement volume fraction because of the limitation of reinforcement CTEs. SrxBa1-xTiO3 (SBT) powder presents negative thermal expansion behavior during the phase transformation from tetragonal to cubic phase. Here, we demonstrate that the phase transformation of SBT can be utilized to reduce and design the thermal expansion properties of SBT particle-reinforced Cu (SBT/Cu) composite, and ultralow CTE can be obtained in SBT/Cu composite. The X-ray diffraction analysis on heating indicates that the temperature range of phase transformation is extended greatly, therefore, the low CTE can be achieved within wide temperature range. Landau-Devonshire theory study on the phase transformation behaviors of SBT particles in the composite indicates that thermal mismatch stress significantly affects the Curie temperature of SBT particles and the CTE of the composite. The results given in the present study provide a new approach to design the MMCs with low CTE.

Influence of volume magnetostriction on the thermodynamic properties of Ni-Mn-Ga shape memory alloys

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kosogor, Anna; Institute of Magnetism, 36-b, Vernadsky Str., Kyiv 03142; Donetsk Institute for Physics and Engineering, Kyiv 03028

2015-10-07

In the present article, the thermodynamic properties of Ni-Mn-Ga ferromagnetic shape memory alloys exhibiting the martensitic transformations (MTs) above and below Curie temperature are compared. It is shown that when MT goes below Curie temperature, the elastic and thermal properties of alloy noticeably depend on magnetization value due to spontaneous volume magnetostriction. However, the separation of magnetic parts from the basic characteristics of MT is a difficult task, because the volume magnetostriction does not qualitatively change the transformational behaviour of alloy. This problem is solved for several Ni-Mn-Ga alloys by means of the quantitative theoretical analysis of experimental data obtainedmore » in the course of stress-strain tests. For each alloy, the entropy change and the transformation heat evolved in the course of MT are evaluated, first, from the results of stress-strain tests and, second, from differential scanning calorimetry data. For all alloys, a quantitative agreement between the values obtained in two different ways is observed. It is shown that the magnetic part of transformation heat exceeds the non-magnetic one for the Ni-Mn-Ga alloys undergoing MTs in ferromagnetic state, while the elevated values of transformation heat measured for the alloys undergoing MTs in paramagnetic state are caused by large MT strains.« less

Influence of volume magnetostriction on the thermodynamic properties of Ni-Mn-Ga shape memory alloys

NASA Astrophysics Data System (ADS)

Kosogor, Anna; L'vov, Victor A.; Cesari, Eduard

2015-10-01

In the present article, the thermodynamic properties of Ni-Mn-Ga ferromagnetic shape memory alloys exhibiting the martensitic transformations (MTs) above and below Curie temperature are compared. It is shown that when MT goes below Curie temperature, the elastic and thermal properties of alloy noticeably depend on magnetization value due to spontaneous volume magnetostriction. However, the separation of magnetic parts from the basic characteristics of MT is a difficult task, because the volume magnetostriction does not qualitatively change the transformational behaviour of alloy. This problem is solved for several Ni-Mn-Ga alloys by means of the quantitative theoretical analysis of experimental data obtained in the course of stress-strain tests. For each alloy, the entropy change and the transformation heat evolved in the course of MT are evaluated, first, from the results of stress-strain tests and, second, from differential scanning calorimetry data. For all alloys, a quantitative agreement between the values obtained in two different ways is observed. It is shown that the magnetic part of transformation heat exceeds the non-magnetic one for the Ni-Mn-Ga alloys undergoing MTs in ferromagnetic state, while the elevated values of transformation heat measured for the alloys undergoing MTs in paramagnetic state are caused by large MT strains.

A fuzzy feature fusion method for auto-segmentation of gliomas with multi-modality diffusion and perfusion magnetic resonance images in radiotherapy.

PubMed

Guo, Lu; Wang, Ping; Sun, Ranran; Yang, Chengwen; Zhang, Ning; Guo, Yu; Feng, Yuanming

2018-02-19

The diffusion and perfusion magnetic resonance (MR) images can provide functional information about tumour and enable more sensitive detection of the tumour extent. We aimed to develop a fuzzy feature fusion method for auto-segmentation of gliomas in radiotherapy planning using multi-parametric functional MR images including apparent diffusion coefficient (ADC), fractional anisotropy (FA) and relative cerebral blood volume (rCBV). For each functional modality, one histogram-based fuzzy model was created to transform image volume into a fuzzy feature space. Based on the fuzzy fusion result of the three fuzzy feature spaces, regions with high possibility belonging to tumour were generated automatically. The auto-segmentations of tumour in structural MR images were added in final auto-segmented gross tumour volume (GTV). For evaluation, one radiation oncologist delineated GTVs for nine patients with all modalities. Comparisons between manually delineated and auto-segmented GTVs showed that, the mean volume difference was 8.69% (±5.62%); the mean Dice's similarity coefficient (DSC) was 0.88 (±0.02); the mean sensitivity and specificity of auto-segmentation was 0.87 (±0.04) and 0.98 (±0.01) respectively. High accuracy and efficiency can be achieved with the new method, which shows potential of utilizing functional multi-parametric MR images for target definition in precision radiation treatment planning for patients with gliomas.

Homogeneous illusion device exhibiting transformed and shifted scattering effect

NASA Astrophysics Data System (ADS)

Mei, Jin-Shuo; Wu, Qun; Zhang, Kuang; He, Xun-Jun; Wang, Yue

2016-06-01

Based on the theory of transformation optics, a type of homogeneous illusion device exhibiting transformed and shifted scattering effect is proposed in this paper. The constitutive parameters of the proposed device are derived, and full-wave simulations are performed to validate the electromagnetic properties of transformed and shifted scattering effect. The simulation results show that the proposed device not only can visually shift the image of target in two dimensions, but also can visually transform the shape of target. It is expected that such homogeneous illusion device could possess potential applications in military camouflage and other field of electromagnetic engineering.

Continuous activation of Nrf2 and its target antioxidant enzymes leads to arsenite-induced malignant transformation of human bronchial epithelial cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Xu; Wang, Dapeng; Department of Toxicology, School of Public Health, Guizhou Medical University, Guiyang, Guizhou

Long-term exposure to arsenite leads to human lung cancer, but the underlying mechanisms of carcinogenesis remain obscure. The transcription factor of nuclear factor-erythroid-2 p45-related factor (Nrf2)-mediated antioxidant response represents a critical cellular defense mechanism and protection against various diseases. Paradoxically, emerging data suggest that the constitutive activation of Nrf2 is associated with cancer development, progression and chemotherapy resistance. However, the role of Nrf2 in the occurrence of cancer induced by long-term arsenite exposure remains to be fully understood. By establishing transformed human bronchial epithelial (HBE) cells via chronic low-dose arsenite treatment, we showed that, in acquiring this malignant phenotype, continuousmore » low level of ROS and sustained enhancement of Nrf2 and its target antioxidant enzyme levels were observed in the later-stage of arsenite-induced cell transformation. The downregulation of Keap1 level may be responsible for the over-activation of Nrf2 and its target enzymes. To validate these observations, Nrf2 was knocked down in arsenite-transformed HBE cells by SiRNA transfection, and the levels of Nrf2 and its target antioxidant enzymes, ROS, cell proliferation, migration, and colony formation were determined following these treatments. Results showed that blocked Nrf2 expression significantly reduced Nrf2 and its target antioxidant enzyme levels, restored ROS levels, and eventually suppressed cell proliferation, migration, and colony formation of the transformed cells. In summary, the results of the study strongly suggested that the continuous activation of Nrf2 and its target antioxidant enzymes led to the over-depletion of intracellular ROS levels, which contributed to arsenite-induced HBE cell transformation. - Highlights: • Low level, long term arsenite exposure induces malignant transformation in vitro. • Long term arsenite exposure reduces ROS and MDA levels. • Long term arsenite exposure enhances Nrf2-mediated antioxidant levels. • Knockdown of Nrf2 reduces malignant degree of arsenite-transformed cells.« less

Technical Note: Robust measurement of the slice-sensitivity profile in breast tomosynthesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maki, Aili K., E-mail: aili.maki@sri.utoronto.ca

2016-08-15

Purpose: The purpose of this work is to improve the repeatability of the measurement of the slice-sensitivity profile (SSP) in reconstructed breast tomosynthesis volumes. Methods: A grid of aluminum ball-bearings (BBs) within a PMMA phantom was imaged on breast tomosynthesis systems from three different manufacturers. The full-width half-maximum (FWHM) values were measured for the SSPs of the BBs in the reconstructed volumes. The effect of transforming the volumes from a Cartesian coordinate system (CCS) to a cone-beam coordinate system (CBCS) on the variability in the FWHM values was assessed. Results: Transforming the volumes from a CCS to a CBCS beforemore » measuring the SSPs reduced the coefficient of variation (COV) in the measurements of FWHM in repeated measurements by 56% and reduced the dependence of the FWHM values on the location of the BBs within the reconstructed volume by 76%. Conclusions: Measuring the SSP in the volumes in a CBCS improves the robustness of the measurement.« less

Interoperability format translation and transformation between IFC architectural design file and simulation file formats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chao, Tian-Jy; Kim, Younghun

Automatically translating a building architecture file format (Industry Foundation Class) to a simulation file, in one aspect, may extract data and metadata used by a target simulation tool from a building architecture file. Interoperability data objects may be created and the extracted data is stored in the interoperability data objects. A model translation procedure may be prepared to identify a mapping from a Model View Definition to a translation and transformation function. The extracted data may be transformed using the data stored in the interoperability data objects, an input Model View Definition template, and the translation and transformation function tomore » convert the extracted data to correct geometric values needed for a target simulation file format used by the target simulation tool. The simulation file in the target simulation file format may be generated.« less

An accurate segmentation method for volumetry of brain tumor in 3D MRI

NASA Astrophysics Data System (ADS)

Wang, Jiahui; Li, Qiang; Hirai, Toshinori; Katsuragawa, Shigehiko; Li, Feng; Doi, Kunio

2008-03-01

Accurate volumetry of brain tumors in magnetic resonance imaging (MRI) is important for evaluating the interval changes in tumor volumes during and after treatment, and also for planning of radiation therapy. In this study, an automated volumetry method for brain tumors in MRI was developed by use of a new three-dimensional (3-D) image segmentation technique. First, the central location of a tumor was identified by a radiologist, and then a volume of interest (VOI) was determined automatically. To substantially simplify tumor segmentation, we transformed the 3-D image of the tumor into a two-dimensional (2-D) image by use of a "spiral-scanning" technique, in which a radial line originating from the center of the tumor scanned the 3-D image spirally from the "north pole" to the "south pole". The voxels scanned by the radial line provided a transformed 2-D image. We employed dynamic programming to delineate an "optimal" outline of the tumor in the transformed 2-D image. We then transformed the optimal outline back into 3-D image space to determine the volume of the tumor. The volumetry method was trained and evaluated by use of 16 cases with 35 brain tumors. The agreement between tumor volumes provided by computer and a radiologist was employed as a performance metric. Our method provided relatively accurate results with a mean agreement value of 88%.

Origins of microstructural transformations in charged vesicle suspensions: the crowding hypothesis.

PubMed

Seth, Mansi; Ramachandran, Arun; Murch, Bruce P; Leal, L Gary

2014-09-02

It is observed that charged unilamellar vesicles in a suspension can spontaneously deflate and subsequently transition to form bilamellar vesicles, even in the absence of externally applied triggers such as salt or temperature gradients. We provide strong evidence that the driving force for this deflation-induced transition is the repulsive electrostatic pressure between charged vesicles in concentrated suspensions, above a critical effective volume fraction. We use volume fraction measurements and cryogenic transmission electron microscopy imaging to quantitatively follow both the macroscopic and microstructural time-evolution of cationic diC18:1 DEEDMAC vesicle suspensions at different surfactant and salt concentrations. A simple model is developed to estimate the extent of deflation of unilamellar vesicles caused by electrostatic interactions with neighboring vesicles. It is determined that when the effective volume fraction of the suspension exceeds a critical value, charged vesicles in a suspension can experience "crowding" due to overlap of their electrical double layers, which can result in deflation and subsequent microstructural transformations to reduce the effective volume fraction of the suspension. Ordinarily in polydisperse colloidal suspensions, particles interacting via a repulsive potential transform into a glassy state above a critical volume fraction. The behavior of charged vesicle suspensions reported in this paper thus represents a new mechanism for the relaxation of repulsive interactions in crowded situations.

Targeted Gene Deletion in Cordyceps militaris Using the Split-Marker Approach.

PubMed

Lou, HaiWei; Ye, ZhiWei; Yun, Fan; Lin, JunFang; Guo, LiQiong; Chen, BaiXiong; Mu, ZhiXian

2018-05-01

The macrofungus Cordyceps militaris contains many kinds of bioactive ingredients that are regulated by functional genes, but the functions of many genes in C. militaris are still unknown. In this study, to improve the frequency of homologous integration, a genetic transformation system based on a split-marker approach was developed for the first time in C. militaris to knock out a gene encoding a terpenoid synthase (Tns). The linear and split-marker deletion cassettes were constructed and introduced into C. militaris protoplasts by PEG-mediated transformation. The transformation of split-marker fragments resulted in a higher efficiency of targeted gene disruption than the transformation of linear deletion cassettes did. The color phenotype of the Tns gene deletion mutants was different from that of wild-type C. militaris. Moreover, a PEG-mediated protoplast transformation system was established, and stable genetic transformants were obtained. This method of targeted gene deletion represents an important tool for investigating the role of C. militaris genes.

The surface science of nanocrystals

NASA Astrophysics Data System (ADS)

Boles, Michael A.; Ling, Daishun; Hyeon, Taeghwan; Talapin, Dmitri V.

2016-02-01

All nanomaterials share a common feature of large surface-to-volume ratio, making their surfaces the dominant player in many physical and chemical processes. Surface ligands -- molecules that bind to the surface -- are an essential component of nanomaterial synthesis, processing and application. Understanding the structure and properties of nanoscale interfaces requires an intricate mix of concepts and techniques borrowed from surface science and coordination chemistry. Our Review elaborates these connections and discusses the bonding, electronic structure and chemical transformations at nanomaterial surfaces. We specifically focus on the role of surface ligands in tuning and rationally designing properties of functional nanomaterials. Given their importance for biomedical (imaging, diagnostics and therapeutics) and optoelectronic (light-emitting devices, transistors, solar cells) applications, we end with an assessment of application-targeted surface engineering.

Positive and negative effects of dielectric breakdown in transformer oil based magnetic fluids

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Jong-Chul, E-mail: jclee01@gwnu.ac.kr; Lee, Won-Ho; Lee, Se-Hee

The transformer oil based magnetic fluids can be considered as the next-generation insulation fluids because they offer exciting new possibilities to enhance dielectric breakdown voltage as well as heat transfer performance compared to pure transformer oils. In this study, we have investigated the dielectric breakdown strength of the fluids with the various volume concentrations of nanoparticles in accordance with IEC 156 standard and have tried to find the reason for changing the dielectric breakdown voltage of the fluids from the magnetic field analysis. It was found that the dielectric breakdown voltage of pure transformer oil is around 12 kV withmore » the gap distance of 1.5 mm. In the case of our transformer oil-based magnetic fluids with 0.08% < Φ < 0.6% (Φ means the volume concentration of magnetic nanoparticles), the dielectric breakdown voltage shows above 40 kV, which is 3.3 times higher positively than that of pure transformer oil. Negatively in the case when the volume concentration of magnetic nanoparticles is above 0.65%, the dielectric breakdown voltage decreases reversely. From the magnetic field analysis, the reason might be considered as two situations: the positive is for the conductive nanoparticles dispersed well near the electrodes, which play an important role in converting fast electrons to slow negatively charged particles, and the negative is for the agglomeration of the particles near the electrodes, which leads to the breakdown initiation.« less

Are there benefits or harm from pressure targeting during lung-protective ventilation?

PubMed

MacIntyre, Neil R; Sessler, Curtis N

2010-02-01

Mechanically, breath design is usually either flow/volume-targeted or pressure-targeted. Both approaches can effectively provide lung-protective ventilation, but they prioritize different ventilation parameters, so their responses to changing respiratory-system mechanics and patient effort are different. These different response behaviors have advantages and disadvantages that can be important in specific circumstances. Flow/volume targeting guarantees a set minute ventilation but sometimes may be difficult to synchronize with patient effort, and it will not limit inspiratory pressure. In contrast, pressure targeting, with its variable flow, may be easier to synchronize and will limit inspiratory pressure, but it provides no control over delivered volume. Skilled clinicians can maximize benefits and minimize problems with either flow/volume targeting or pressure targeting. Indeed, as is often the case in managing complex life-support devices, it is operator expertise rather than the device design features that most impacts patient outcomes.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yu, Cun; Ren, Yang; Cui, Lishan

Under high pressure, materials usually shrink during compression as described by an equation of state. Here, we present the anomalous volume expansion behavior of a one-dimensional Nb nanowire embedded in a NiTi transforming matrix, while the matrix undergoes a pressure-induced martensitic transformation. The Nb volume expansion depends on the NiTi transition pressure range from the matrix, which is controlled by the shear strain induced by different pressure transmitting media. The transformation-induced interfacial stresses between Nb and NiTi may play a major role in this anomaly. In conclusion, our discovery sheds new light on the nano-interfacial effect on mechanical anomalies inmore » heterogeneous systems during a pressure-induced phase transition.« less

Water-filled balloon in the postoperative resection cavity improves dose distribution to target volumes in radiotherapy of maxillary sinus carcinoma.

PubMed

Zhang, Qun; Lin, Shi-Rong; He, Fang; Kang, De-Hua; Chen, Guo-Zhang; Luo, Wei

2011-11-01

Postoperative radiotherapy is a major treatment for patients with maxillary sinus carcinoma. However, the irregular resection cavity poses a technical difficulty for this treatment, causing uneven dose distribution to target volumes. In this study, we evaluated the dose distribution to target volumes and normal tissues in postoperative intensity-modulated radiotherapy (IMRT) after placing a water-filled balloon into the resection cavity. Three postoperative patients with advanced maxillary sinus carcinoma were selected in this trial. Water-filled balloons and supporting dental stents were fabricated according to the size of the maxillary resection cavity. Simulation CT scans were performed with or without water-filled balloons, IMRT treatment plans were established, and dose distribution to target volumes and organs at risk were evaluated. Compared to those in the treatment plan without balloons, the dose (D98) delivered to 98% of the gross tumor volume (GTV) increased by 2.1 Gy (P = 0.009), homogeneity index (HI) improved by 2.3% (P = 0.001), and target volume conformity index (TCI) of 68 Gy increased by 18.5% (P = 0.011) in the plan with balloons. Dosimetry endpoints of normal tissues around target regions in both plans were not significantly different (P > 0.05) except for the optic chiasm. In the plan without balloons, 68 Gy high-dose regions did not entirely cover target volumes in the ethmoid sinus, posteromedial wall of the maxillary sinus, or surgical margin of the hard palate. In contrast, 68 Gy high-dose regions entirely covered the GTV in the plan with balloons. These results suggest that placing a water-filled balloon in the resection cavity for postoperative IMRT of maxillary sinus carcinoma can reduce low-dose regions and markedly and simultaneously increase dose homogeneity and conformity of target volumes.

PET/CT-guided treatment planning for paediatric cancer patients: a simulation study of proton and conventional photon therapy

PubMed Central

Brodin, N P; Björk-Eriksson, T; Birk Christensen, C; Kiil-Berthelsen, A; Aznar, M C; Hollensen, C; Markova, E; Munck af Rosenschöld, P

2015-01-01

Objective: To investigate the impact of including fluorine-18 fludeoxyglucose (18F-FDG) positron emission tomography (PET) scanning in the planning of paediatric radiotherapy (RT). Methods: Target volumes were first delineated without and subsequently re-delineated with access to 18F-FDG PET scan information, on duplicate CT sets. RT plans were generated for three-dimensional conformal photon RT (3DCRT) and intensity-modulated proton therapy (IMPT). The results were evaluated by comparison of target volumes, target dose coverage parameters, normal tissue complication probability (NTCP) and estimated risk of secondary cancer (SC). Results: Considerable deviations between CT- and PET/CT-guided target volumes were seen in 3 out of the 11 patients studied. However, averaging over the whole cohort, CT or PET/CT guidance introduced no significant difference in the shape or size of the target volumes, target dose coverage, irradiated volumes, estimated NTCP or SC risk, neither for IMPT nor 3DCRT. Conclusion: Our results imply that the inclusion of PET/CT scans in the RT planning process could have considerable impact for individual patients. There were no general trends of increasing or decreasing irradiated volumes, suggesting that the long-term morbidity of RT in childhood would on average remain largely unaffected. Advances in knowledge: 18F-FDG PET-based RT planning does not systematically change NTCP or SC risk for paediatric cancer patients compared with CT only. 3 out of 11 patients had a distinct change of target volumes when PET-guided planning was introduced. Dice and mismatch metrics are not sufficient to assess the consequences of target volume differences in the context of RT. PMID:25494657

Image-guided ex-vivo targeting accuracy using a laparoscopic tissue localization system

NASA Astrophysics Data System (ADS)

Bieszczad, Jerry; Friets, Eric; Knaus, Darin; Rauth, Thomas; Herline, Alan; Miga, Michael; Galloway, Robert; Kynor, David

2007-03-01

In image-guided surgery, discrete fiducials are used to determine a spatial registration between the location of surgical tools in the operating theater and the location of targeted subsurface lesions and critical anatomic features depicted in preoperative tomographic image data. However, the lack of readily localized anatomic landmarks has greatly hindered the use of image-guided surgery in minimally invasive abdominal procedures. To address these needs, we have previously described a laser-based system for localization of internal surface anatomy using conventional laparoscopes. During a procedure, this system generates a digitized, three-dimensional representation of visible anatomic surfaces in the abdominal cavity. This paper presents the results of an experiment utilizing an ex-vivo bovine liver to assess subsurface targeting accuracy achieved using our system. During the experiment, several radiopaque targets were inserted into the liver parenchyma. The location of each target was recorded using an optically-tracked insertion probe. The liver surface was digitized using our system, and registered with the liver surface extracted from post-procedure CT images. This surface-based registration was then used to transform the position of the inserted targets into the CT image volume. The target registration error (TRE) achieved using our surface-based registration (given a suitable registration algorithm initialization) was 2.4 mm +/- 1.0 mm. A comparable TRE (2.6 mm +/- 1.7 mm) was obtained using a registration based on traditional fiducial markers placed on the surface of the same liver. These results indicate the potential of fiducial-free, surface-to-surface registration for image-guided lesion targeting in minimally invasive abdominal surgery.

Projected Improvements in Accelerated Partial Breast Irradiation Using a Novel Breast Stereotactic Radiotherapy Device: A Dosimetric Analysis.

PubMed

Snider, James W; Mutaf, Yildirim; Nichols, Elizabeth; Hall, Andrea; Vadnais, Patrick; Regine, William F; Feigenberg, Steven J

2017-01-01

Accelerated partial breast irradiation has caused higher than expected rates of poor cosmesis. At our institution, a novel breast stereotactic radiotherapy device has demonstrated dosimetric distributions similar to those in brachytherapy. This study analyzed comparative dose distributions achieved with the device and intensity-modulated radiation therapy accelerated partial breast irradiation. Nine patients underwent computed tomography simulation in the prone position using device-specific immobilization on an institutional review board-approved protocol. Accelerated partial breast irradiation target volumes (planning target volume_10mm) were created per the National Surgical Adjuvant Breast and Bowel Project B-39 protocol. Additional breast stereotactic radiotherapy volumes using smaller margins (planning target volume_3mm) were created based on improved immobilization. Intensity-modulated radiation therapy and breast stereotactic radiotherapy accelerated partial breast irradiation plans were separately generated for appropriate volumes. Plans were evaluated based on established dosimetric surrogates of poor cosmetic outcomes. Wilcoxon rank sum tests were utilized to contrast volumes of critical structures receiving a percentage of total dose ( Vx). The breast stereotactic radiotherapy device consistently reduced dose to all normal structures with equivalent target coverage. The ipsilateral breast V20-100 was significantly reduced ( P < .05) using planning target volume_10mm, with substantial further reductions when targeting planning target volume_3mm. Doses to the chest wall, ipsilateral lung, and breast skin were also significantly lessened. The breast stereotactic radiotherapy device's uniform dosimetric improvements over intensity-modulated accelerated partial breast irradiation in this series indicate a potential to improve outcomes. Clinical trials investigating this benefit have begun accrual.

Anomalous behavior of cristobalite in helium under high pressure

NASA Astrophysics Data System (ADS)

Sato, Tomoko; Takada, Hiroto; Yagi, Takehiko; Gotou, Hirotada; Okada, Taku; Wakabayashi, Daisuke; Funamori, Nobumasa

2013-01-01

We have investigated the high-pressure behavior of cristobalite in helium by powder X-ray diffraction. Cristobalite transformed to a new phase at about 8 GPa. This phase is supposed to have a molar volume of about 30 % larger than cristobalite, suggesting the dissolution of helium atoms in its interstitial voids. On further compression, the new phase transformed to a different phase which showed an X-ray diffraction pattern similar to cristobalite X-I at about 21 GPa. On the other hand, when the new phase was decompressed, it transformed to another new phase at about 7 GPa, which is also supposed to have a molar volume of about 25 % larger than cristobalite. On further decompression, the second new phase transformed to cristobalite II at about 2 GPa. In contrast to cristobalite, quartz did not show anomalous behavior in helium. The behavior of cristobalite in helium was also consistent with that in other mediums up to about 8 GPa, where the volume of cristobalite became close to that of quartz. These results suggest that dissolution of helium may be controlled not only by the density (amount of voids) but also by the network structure of SiO4 tetrahedra (topology of voids).

Transform Decoding of Reed-Solomon Codes. Volume I. Algorithm and Signal Processing Structure

DTIC Science & Technology

1982-11-01

systematic channel co.’e. 1. lake the inverse transform of the r- ceived se, - nee. 2. Isolate the error syndrome from the inverse transform and use... inverse transform is identic l with interpolation of the polynomial a(z) from its n values. In order to generate a Reed-Solomon (n,k) cooce, we let the set...in accordance with the transform of equation (4). If we were to apply the inverse transform of equa- tion (6) to the coefficient sequence of A(z), we

Poisson noise removal with pyramidal multi-scale transforms

NASA Astrophysics Data System (ADS)

Woiselle, Arnaud; Starck, Jean-Luc; Fadili, Jalal M.

2013-09-01

In this paper, we introduce a method to stabilize the variance of decimated transforms using one or two variance stabilizing transforms (VST). These VSTs are applied to the 3-D Meyer wavelet pyramidal transform which is the core of the first generation 3D curvelets. This allows us to extend these 3-D curvelets to handle Poisson noise, that we apply to the denoising of a simulated cosmological volume.

CrossTalk: The Journal of Defense Software Engineering. Volume 19, Number 5

DTIC Science & Technology

2006-05-01

Coming Events Web Sites Call for Articles Visit CrossTalk at the SSTC BackTalk Transforming: Business , Security ,Warfighting CrossTalk 76 SMXG CO-SPONSOR...theme “Transforming: Business , Security , Warfighting.” Transformation is not just the current buzzword: Many industries and the military have...systems. Transforming: Business , Security ,Warfighting Characteristic edocfosenilnoillim001-01eziS Number of external interfaces 30-300 Number of

A Semantic Transformation Methodology for the Secondary Use of Observational Healthcare Data in Postmarketing Safety Studies.

PubMed

Pacaci, Anil; Gonul, Suat; Sinaci, A Anil; Yuksel, Mustafa; Laleci Erturkmen, Gokce B

2018-01-01

Background: Utilization of the available observational healthcare datasets is key to complement and strengthen the postmarketing safety studies. Use of common data models (CDM) is the predominant approach in order to enable large scale systematic analyses on disparate data models and vocabularies. Current CDM transformation practices depend on proprietarily developed Extract-Transform-Load (ETL) procedures, which require knowledge both on the semantics and technical characteristics of the source datasets and target CDM. Purpose: In this study, our aim is to develop a modular but coordinated transformation approach in order to separate semantic and technical steps of transformation processes, which do not have a strict separation in traditional ETL approaches. Such an approach would discretize the operations to extract data from source electronic health record systems, alignment of the source, and target models on the semantic level and the operations to populate target common data repositories. Approach: In order to separate the activities that are required to transform heterogeneous data sources to a target CDM, we introduce a semantic transformation approach composed of three steps: (1) transformation of source datasets to Resource Description Framework (RDF) format, (2) application of semantic conversion rules to get the data as instances of ontological model of the target CDM, and (3) population of repositories, which comply with the specifications of the CDM, by processing the RDF instances from step 2. The proposed approach has been implemented on real healthcare settings where Observational Medical Outcomes Partnership (OMOP) CDM has been chosen as the common data model and a comprehensive comparative analysis between the native and transformed data has been conducted. Results: Health records of ~1 million patients have been successfully transformed to an OMOP CDM based database from the source database. Descriptive statistics obtained from the source and target databases present analogous and consistent results. Discussion and Conclusion: Our method goes beyond the traditional ETL approaches by being more declarative and rigorous. Declarative because the use of RDF based mapping rules makes each mapping more transparent and understandable to humans while retaining logic-based computability. Rigorous because the mappings would be based on computer readable semantics which are amenable to validation through logic-based inference methods.

Atrial natriuretic peptide: a magic bullet for cancer therapy targeting Wnt signaling and cellular pH regulators.

PubMed

Serafino, A; Pierimarchi, P

2014-01-01

Atrial natriuretic peptide (ANP) is a cardiac hormone playing a crucial role in cardiovascular homeostasis mainly through blood volume and pressure regulation. In the last years, the new property ascribed to ANP of inhibiting tumor growth both in vitro and in vivo has made this peptide an attractive candidate for anticancer therapy. The molecular mechanism underlying the anti-proliferative effect of ANP has been mainly related to its interaction with the specific receptors NPRs, through which this natriuretic hormone inhibits some metabolic targets critical for cancer development, including the Ras-MEK1⁄2-ERK1⁄2 kinase cascade, functioning as a multikinase inhibitor. In this review we summarize the current knowledge on this topic, focusing on our recent data demonstrating that the antitumor activity of this natriuretic hormone is also mediated by a concomitant effect on the Wnt/β-catenin pathway and on the pH regulation ability of cancer cells, through a Frizzled-related mechanism. This peculiarity of simultaneously targeting two processes crucial for neoplastic transformation and solid tumor survival reinforces the utility of ANP for the development of both preventive and therapeutic strategies.

A novel ship CFAR detection algorithm based on adaptive parameter enhancement and wake-aided detection in SAR images

NASA Astrophysics Data System (ADS)

Meng, Siqi; Ren, Kan; Lu, Dongming; Gu, Guohua; Chen, Qian; Lu, Guojun

2018-03-01

Synthetic aperture radar (SAR) is an indispensable and useful method for marine monitoring. With the increase of SAR sensors, high resolution images can be acquired and contain more target structure information, such as more spatial details etc. This paper presents a novel adaptive parameter transform (APT) domain constant false alarm rate (CFAR) to highlight targets. The whole method is based on the APT domain value. Firstly, the image is mapped to the new transform domain by the algorithm. Secondly, the false candidate target pixels are screened out by the CFAR detector to highlight the target ships. Thirdly, the ship pixels are replaced by the homogeneous sea pixels. And then, the enhanced image is processed by Niblack algorithm to obtain the wake binary image. Finally, normalized Hough transform (NHT) is used to detect wakes in the binary image, as a verification of the presence of the ships. Experiments on real SAR images validate that the proposed transform does enhance the target structure and improve the contrast of the image. The algorithm has a good performance in the ship and ship wake detection.

International Spine Radiosurgery Consortium Consensus Guidelines for Target Volume Definition in Spinal Stereotactic Radiosurgery

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cox, Brett W., E-mail: coxb@mskcc.org; Spratt, Daniel E.; Lovelock, Michael

2012-08-01

Purpose: Spinal stereotactic radiosurgery (SRS) is increasingly used to manage spinal metastases. However, target volume definition varies considerably and no consensus target volume guidelines exist. This study proposes consensus target volume definitions using common scenarios in metastatic spine radiosurgery. Methods and Materials: Seven radiation oncologists and 3 neurological surgeons with spinal radiosurgery expertise independently contoured target and critical normal structures for 10 cases representing common scenarios in metastatic spine radiosurgery. Each set of volumes was imported into the Computational Environment for Radiotherapy Research. Quantitative analysis was performed using an expectation maximization algorithm for Simultaneous Truth and Performance Level Estimation (STAPLE)more » with kappa statistics calculating agreement between physicians. Optimized confidence level consensus contours were identified using histogram agreement analysis and characterized to create target volume definition guidelines. Results: Mean STAPLE agreement sensitivity and specificity was 0.76 (range, 0.67-0.84) and 0.97 (range, 0.94-0.99), respectively, for gross tumor volume (GTV) and 0.79 (range, 0.66-0.91) and 0.96 (range, 0.92-0.98), respectively, for clinical target volume (CTV). Mean kappa agreement was 0.65 (range, 0.54-0.79) for GTV and 0.64 (range, 0.54-0.82) for CTV (P<.01 for GTV and CTV in all cases). STAPLE histogram agreement analysis identified optimal consensus contours (80% confidence limit). Consensus recommendations include that the CTV should include abnormal marrow signal suspicious for microscopic invasion and an adjacent normal bony expansion to account for subclinical tumor spread in the marrow space. No epidural CTV expansion is recommended without epidural disease, and circumferential CTVs encircling the cord should be used only when the vertebral body, bilateral pedicles/lamina, and spinous process are all involved or there is extensive metastatic disease along the circumference of the epidural space. Conclusions: This report provides consensus guidelines for target volume definition for spinal metastases receiving upfront SRS in common clinical situations.« less

Phase-Transformation-Induced Extra Thermal Expansion Behavior of (SrxBa1–x)TiO3/Cu Composite

PubMed Central

Sheng, Jie; Wang, Lidong; Li, Shouwei; Yin, Benke; Liu, Xiangli; Fei, Wei-Dong

2016-01-01

The properties of metal matrix composites (MMCs) can be optimized effectively through adjusting the type or the volume fraction of reinforcement. Generally, the coefficient of thermal expansion (CTE) of MMCs can be reduced by increasing the volume fraction of the reinforcement with lower CTE than metal matrix. However, it is great challenge to fabricate low CTE MMCs with low reinforcement volume fraction because of the limitation of reinforcement CTEs. SrxBa1−xTiO3 (SBT) powder presents negative thermal expansion behavior during the phase transformation from tetragonal to cubic phase. Here, we demonstrate that the phase transformation of SBT can be utilized to reduce and design the thermal expansion properties of SBT particle-reinforced Cu (SBT/Cu) composite, and ultralow CTE can be obtained in SBT/Cu composite. The X-ray diffraction analysis on heating indicates that the temperature range of phase transformation is extended greatly, therefore, the low CTE can be achieved within wide temperature range. Landau-Devonshire theory study on the phase transformation behaviors of SBT particles in the composite indicates that thermal mismatch stress significantly affects the Curie temperature of SBT particles and the CTE of the composite. The results given in the present study provide a new approach to design the MMCs with low CTE. PMID:27255420

Video denoising, deblocking, and enhancement through separable 4-D nonlocal spatiotemporal transforms.

PubMed

Maggioni, Matteo; Boracchi, Giacomo; Foi, Alessandro; Egiazarian, Karen

2012-09-01

We propose a powerful video filtering algorithm that exploits temporal and spatial redundancy characterizing natural video sequences. The algorithm implements the paradigm of nonlocal grouping and collaborative filtering, where a higher dimensional transform-domain representation of the observations is leveraged to enforce sparsity, and thus regularize the data: 3-D spatiotemporal volumes are constructed by tracking blocks along trajectories defined by the motion vectors. Mutually similar volumes are then grouped together by stacking them along an additional fourth dimension, thus producing a 4-D structure, termed group, where different types of data correlation exist along the different dimensions: local correlation along the two dimensions of the blocks, temporal correlation along the motion trajectories, and nonlocal spatial correlation (i.e., self-similarity) along the fourth dimension of the group. Collaborative filtering is then realized by transforming each group through a decorrelating 4-D separable transform and then by shrinkage and inverse transformation. In this way, the collaborative filtering provides estimates for each volume stacked in the group, which are then returned and adaptively aggregated to their original positions in the video. The proposed filtering procedure addresses several video processing applications, such as denoising, deblocking, and enhancement of both grayscale and color data. Experimental results prove the effectiveness of our method in terms of both subjective and objective visual quality, and show that it outperforms the state of the art in video denoising.

Research on autonomous identification of airport targets based on Gabor filtering and Radon transform

NASA Astrophysics Data System (ADS)

Yi, Juan; Du, Qingyu; Zhang, Hong jiang; Zhang, Yao lei

2017-11-01

Target recognition is a leading key technology in intelligent image processing and application development at present, with the enhancement of computer processing ability, autonomous target recognition algorithm, gradually improve intelligence, and showed good adaptability. Taking the airport target as the research object, analysis the airport layout characteristics, construction of knowledge model, Gabor filter and Radon transform based on the target recognition algorithm of independent design, image processing and feature extraction of the airport, the algorithm was verified, and achieved better recognition results.

Phase transformation and sustained load crack growth in ZrO[sub 2] + 3 mol% Y[sub 2]O[sub 3]: Experiments and kinetic modeling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yin, H.; Gao, M.; Wei, R.P.

1995-01-01

To better understand environmentally assisted crack growth (SCG) in yttria stabilized zirconia, experimental studies were undertaken to characterize the kinetics of crack growth and the associated stress/moisture induced phase transformation in ZrO[sub 2] + 3 mol% Y[sub 2]O[sub 3] (3Y-TZP) in water, dry nitrogen and toluene from 3 to 70 C. The results showed that crack growth in water depended strongly on stress intensity factor (K[sub 1]) and temperature (T) and involved the transformation of a thin layer of material near the crack tip from the tetragonal (t) to the monoclinic (m) phase. These results, combined with literature data onmore » moisture-induced phase transformation, suggested that crack growth enhancement by water is controlled by the rate of this transformation and reflects the environmental cracking susceptibility of the transformed m-phase. A model was developed to link subcritical crack growth (SCG) rate to the kinetics of t [yields] m phase transformation. The SCG rate is expressed as an exponential function of stress-free activation energy, a stress-dependent contribution in terms of the mode 1 stress intensity factor K[sub I] and actuation volume, and temperature. The stress-free activation energies for water and the inert environments were determined to be 82 [+-] 3 and 169 [+-] 4 kJ/mol, respectively, at the 95% confidence level, and the corresponding activation volumes were 14 and 35 unit cells. The decreases in activation energy and activation volume may be attributed to a change in surface energy by water.« less

Effect of martensitic transformation on springback behavior of 304L austenitic stainless steel

NASA Astrophysics Data System (ADS)

Fathi, H.; Mohammadian Semnani, H. R.; Emadoddin, E.; Sadeghi, B. Mohammad

2017-09-01

The present paper studies the effect of martensitic transformation on the springback behavior of 304L austenitic stainless steel. Martensite volume fraction was determined at the bent portion under various strain rates after bending test. Martensitic transformation has a significant effect on the springback behavior of this material. The findings of this study indicated that the amount of springback was reduced under a situation of low strain rate, while a higher amount of springback was obtained with a higher strain rate. The reason for this phenomenon is that higher work hardening occurs during the forming process with the low strain rate due to the higher martensite volume fraction, therefore the formability of the sheet is enhanced and it leads to a decreased amount of springback after the bending test. Dependency of the springback on the martensite volume fraction and strain rate was expressed as formulas from the results of the experimental tests and simulation method. Bending tests were simulated using LS-DYNA software and utilizing MAT_TRIP to determine the martensite volume fraction and strain under various strain rates. Experimental result reveals good agreement with the simulation method.

Search Radar Track-Before-Detect Using the Hough Transform.

DTIC Science & Technology

1995-03-01

before - detect processing method which allows previous data to help in target detection. The technique provides many advantages compared to...improved target detection scheme, applicable to search radars, using the Hough transform image processing technique. The system concept involves a track

Experimental Study on the Dielectric Breakdown Voltage of the Insulating Oil Mixed with Magnetic Nanoparticles

NASA Astrophysics Data System (ADS)

Lee, Jong-Chul; Kim, Woo-Young

In this study, we have measured the dielectric breakdown voltage of transformer oil-based nanofluids in accordance with IEC 156 standard and have investigated the dielectric breakdown performance with the application of an external magnetic field and different volume concentrations of magnetic nanoparticles. It is confirmed that the dielectric breakdown voltage of pure transformer oil is about 10 kV with a gap distance of 1 mm between electrodes. In the case of our transformer oil-based nanofluids with 0.08% < Φ < 0.39% (Φ means the volume concentration of magnetic nanoparticles in the fluid), the dielectric breakdown voltage is three times higher than that of pure transformer oil. Furthermore, when the external magnetic field is applied under the experimental vessel, the dielectric breakdown voltage of the nanofluids is above 40 kV, which is 30% higher than that without the external magnetic field.

Heat storage in alloy transformations

NASA Technical Reports Server (NTRS)

Birchenall, C. E.; Gueceri, S. I.; Farkas, D.; Labdon, M. B.; Nagaswami, N.; Pregger, B.

1981-01-01

The feasibility of using metal alloys as thermal energy storage media was determined. The following major elements were studied: (1) identification of congruently transforming alloys and thermochemical property measurements; (2) development of a precise and convenient method for measuring volume change during phase transformation and thermal expansion coefficients; (3) development of a numerical modeling routine for calculating heat flow in cylindrical heat exchangers containing phase change materials; and (4) identification of materials that could be used to contain the metal alloys. Several eutectic alloys and ternary intermetallic phases were determined. A method employing X-ray absorption techniques was developed to determine the coefficients of thermal expansion of both the solid and liquid phases and the volume change during phase transformation from data obtained during one continuous experimental test. The method and apparatus are discussed and the experimental results are presented. The development of the numerical modeling method is presented and results are discussed for both salt and metal alloy phase change media.

Behavioral Investigation on the Frames of Reference Involved in Visuomotor Transformations during Peripheral Arm Reaching

PubMed Central

Pelle, Gina; Perrucci, Mauro Gianni; Galati, Gaspare; Fattori, Patrizia; Galletti, Claudio; Committeri, Giorgia

2012-01-01

Background Several psychophysical experiments found evidence for the involvement of gaze-centered and/or body-centered coordinates in arm-movement planning and execution. Here we aimed at investigating the frames of reference involved in the visuomotor transformations for reaching towards visual targets in space by taking target eccentricity and performing hand into account. Methodology/Principal Findings We examined several performance measures while subjects reached, in complete darkness, memorized targets situated at different locations relative to the gaze and/or to the body, thus distinguishing between an eye-centered and a body-centered frame of reference involved in the computation of the movement vector. The errors seem to be mainly affected by the visual hemifield of the target, independently from its location relative to the body, with an overestimation error in the horizontal reaching dimension (retinal exaggeration effect). The use of several target locations within the perifoveal visual field allowed us to reveal a novel finding, that is, a positive linear correlation between horizontal overestimation errors and target retinal eccentricity. In addition, we found an independent influence of the performing hand on the visuomotor transformation process, with each hand misreaching towards the ipsilateral side. Conclusions While supporting the existence of an internal mechanism of target-effector integration in multiple frames of reference, the present data, especially the linear overshoot at small target eccentricities, clearly indicate the primary role of gaze-centered coding of target location in the visuomotor transformation for reaching. PMID:23272180

Prospective treatment plan-specific action limits for real-time intrafractional monitoring in surface image guided radiosurgery.

PubMed

Yock, Adam D; Pawlicki, Todd; Kim, Gwe-Ya

2016-07-01

In surface image guided radiosurgery, action limits are created to determine at what point intrafractional motion exhibited by the patient is large enough to warrant intervention. Action limit values remain constant across patients despite the fact that patient motion affects the target coverage of brain metastases differently depending on the planning technique and other treatment plan-specific factors. The purpose of this work was twofold. The first purpose was to characterize the sensitivity of single-met per iso and multimet per iso treatment plans to uncorrected patient motion. The second purpose was to describe a method to prospectively determine treatment plan-specific action limits considering this sensitivity. In their surface image guided radiosurgery technique, patient positioning is achieved with a thermoplastic mask that does not cover the patient's face. The patient's exposed face is imaged by a stereoscopic photogrammetry system. It is then compared to a reference surface and monitored throughout treatment. Seventy-two brain metastases (representing 29 patients) were used for this study. Twenty-five mets were treated individually ("single-met per iso plans"), and 47 were treated in a plan simultaneously with at least one other met ("multimet per iso plans"). For each met, the proportion of the gross tumor volume that remained within the 100% prescription isodose line was estimated under the influence of combinations of translations and rotations (0.0-3.0 mm and 0.0°-3.0°, respectively). The target volume and the prescription dose-volume were considered concentric spheres that each encompassed a volume determined from the treatment plan. Plan-specific contour plots and DVHs were created to illustrate the sensitivity of a specific lesion to uncorrected patient motion. Both single-met per iso and multimet per iso plans exhibited compromised target coverage under translations and rotations, though multimet per iso plans were considerably more sensitive to these transformations (2.3% and 39.8%, respectively). Plan-specific contour plots and DVHs were used to illustrate how size, distance from isocenter, and planning technique affect a particular met's sensitivity to motion. Stereotactic radiosurgery treatment plans that treat multiple brain metastases using a common isocenter are particularly susceptible to compromised target coverage as a result of uncorrected patient motion. The use of such a planning technique along with other treatment plan-specific factors should influence patient motion management. A graphical representation of the effect of translations and rotations on any particular plan can be generated to inform clinicians of the appropriate action limit when monitoring intrafractional motion.

Transformative Leadership: A Reader. Counterpoints: Studies in the Postmodern Theory of Education. Volume 409

ERIC Educational Resources Information Center

Shields, Carolyn M., Ed.

2011-01-01

This important, timely, and thought-provoking reader is a collection of original chapters by authors from five different countries, each of whom explores a facet of transformative leadership. Transformative leadership is fundamentally a critical approach to leadership that goes well beyond the tenets of most current leadership theories to focus on…

4-Benzothiazole-7-hydroxyindolinyl diaryl ureas are potent P2Y1 antagonists with favorable pharmacokinetics: low clearance and small volume of distribution.

PubMed

Qiao, Jennifer X; Wang, Tammy C; Hiebert, Sheldon; Hu, Carol H; Schumacher, William A; Spronk, Steven A; Clark, Charles G; Han, Ying; Hua, Ji; Price, Laura A; Shen, Hong; Chacko, Silvi A; Everlof, Gerry; Bostwick, Jeffrey S; Steinbacher, Thomas E; Li, Yi-Xin; Huang, Christine S; Seiffert, Dietmar A; Rehfuss, Robert; Wexler, Ruth R; Lam, Patrick Y S

2014-10-01

Current antithrombotic discovery efforts target compounds that are highly efficacious in thrombus reduction with less bleeding liability than the standard of care. Preclinical data suggest that P2Y1 antagonists may have lower bleeding liabilities than P2Y12 antagonists while providing similar antithrombotic efficacy. This article describes our continuous SAR efforts in a series of 7-hydroxyindolinyl diaryl ureas. When dosed orally, 4-trifluoromethyl-7-hydroxy-3,3-dimethylindolinyl analogue 4 was highly efficacious in a model of arterial thrombosis in rats with limited bleeding. The chemically labile CF3 group in 4 was then transformed to various groups via a novel one-step synthesis, yielding a series of potent P2Y1 antagonists. Among them, the 4-benzothiazole-substituted indolines had desirable PK properties in rats, specifically, low clearance and small volume of distribution. In addition, compound 40 had high i.v. exposure and modest bioavailability, giving it the best overall profile. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Policies to Spur Energy Access. Executive Summary; Volume 1, Engaging the Private Sector in Expanding Access to Electricity; Volume 2, Case Studies to Public-Private Models to Finance Decentralized Electricity Access

DOE Office of Scientific and Technical Information (OSTI.GOV)

Walters, Terri; Rai, Neha; Esterly, Sean

Government policy is one of the most important factors in engaging the private sector in providing universal access to electricity. In particular, the private sector is well positioned to provide decentralized electricity products and services. While policy uncertainty and regulatory barriers can keep enterprises and investors from engaging in the market, targeted policies can create opportunities to leverage private investment and skills to expand electricity access. However, creating a sustainable market requires policies beyond traditional electricity regulation. The report reviews the range of policy issues that impact the development and expansion of a market for decentralized electricity services from establishingmore » an enabling policy environment to catalyzing finance, building human capacity, and integrating energy access with development programs. The case studies in this report show that robust policy frameworks--addressing a wide range of market issues--can lead to rapid transformation in energy access. The report highlights examples of these policies in action Bangladesh, Ethiopia, Mali, Mexico, and Nepal.« less

Dynamics of the microglial/amyloid interaction indicate a role in plaque maintenance.

PubMed

Bolmont, Tristan; Haiss, Florent; Eicke, Daniel; Radde, Rebecca; Mathis, Chester A; Klunk, William E; Kohsaka, Shinichi; Jucker, Mathias; Calhoun, Michael E

2008-04-16

Microglial cells aggregate around amyloid plaques in Alzheimer's disease, but, despite their therapeutic potential, various aspects of their reactive kinetics and role in plaque pathogenesis remain hypothetical. Through use of in vivo imaging and quantitative morphological measures in transgenic mice, we demonstrate that local resident microglia rapidly react to plaque formation by extending processes and subsequently migrating toward plaques, in which individual transformed microglia somata remain spatially stable for weeks. The number of plaque-associated microglia increased at a rate of almost three per plaque per month, independent of plaque volume. Larger plaques were surrounded by larger microglia, and a subset of plaques changed in size over time, with an increase or decrease related to the volume of associated microglia. Far from adopting a more static role, plaque-associated microglia retained rapid process and membrane movement at the plaque/glia interface. Microglia internalized systemically injected amyloid-binding dye at a much higher rate in the vicinity of plaques. These results indicate a role for microglia in plaque maintenance and provide a model with multiple targets for therapeutic intervention.

Dynamics of the Microglial/Amyloid Interaction Indicate a Role in Plaque Maintenance

PubMed Central

Bolmont, Tristan; Haiss, Florent; Eicke, Daniel; Radde, Rebecca; Mathis, Chester A.; Klunk, William E.; Kohsaka, Shinichi; Jucker, Mathias

2008-01-01

Microglial cells aggregate around amyloid plaques in Alzheimer's disease, but, despite their therapeutic potential, various aspects of their reactive kinetics and role in plaque pathogenesis remain hypothetical. Through use of in vivo imaging and quantitative morphological measures in transgenic mice, we demonstrate that local resident microglia rapidly react to plaque formation by extending processes and subsequently migrating toward plaques, in which individual transformed microglia somata remain spatially stable for weeks. The number of plaque-associated microglia increased at a rate of almost three per plaque per month, independent of plaque volume. Larger plaques were surrounded by larger microglia, and a subset of plaques changed in size over time, with an increase or decrease related to the volume of associated microglia. Far from adopting a more static role, plaque-associated microglia retained rapid process and membrane movement at the plaque/glia interface. Microglia internalized systemically injected amyloid-binding dye at a much higher rate in the vicinity of plaques. These results indicate a role for microglia in plaque maintenance and provide a model with multiple targets for therapeutic intervention. PMID:18417708

The Quest for Targets Executing MYC-Dependent Cell Transformation.

PubMed

Hartl, Markus

2016-01-01

MYC represents a transcription factor with oncogenic potential converting multiple cellular signals into a broad transcriptional response, thereby controlling the expression of numerous protein-coding and non-coding RNAs important for cell proliferation, metabolism, differentiation, and apoptosis. Constitutive activation of MYC leads to neoplastic cell transformation, and deregulated MYC alleles are frequently observed in many human cancer cell types. Multiple approaches have been performed to isolate genes differentially expressed in cells containing aberrantly activated MYC proteins leading to the identification of thousands of putative targets. Functional analyses of genes differentially expressed in MYC-transformed cells had revealed that so far more than 40 upregulated or downregulated MYC targets are actively involved in cell transformation or tumorigenesis. However, further systematic and selective approaches are required for determination of the known or yet unidentified targets responsible for processing the oncogenic MYC program. The search for critical targets in MYC-dependent tumor cells is exacerbated by the fact that during tumor development, cancer cells progressively evolve in a multistep process, thereby acquiring their characteristic features in an additive manner. Functional expression cloning, combinatorial gene expression, and appropriate in vivo tests could represent adequate tools for dissecting the complex scenario of MYC-specified cell transformation. In this context, the central goal is to identify a minimal set of targets that suffices to phenocopy oncogenic MYC. Recently developed genomic editing tools could be employed to confirm the requirement of crucial transformation-associated targets. Knowledge about essential MYC-regulated genes is beneficial to expedite the development of specific inhibitors to interfere with growth and viability of human tumor cells in which MYC is aberrantly activated. Approaches based on the principle of synthetic lethality using MYC-overexpressing cancer cells and chemical or RNAi libraries have been employed to search for novel anticancer drugs, also leading to the identification of several druggable targets. Targeting oncogenic MYC effector genes instead of MYC may lead to compounds with higher specificities and less side effects. This class of drugs could also display a wider pharmaceutical window because physiological functions of MYC, which are important for normal cell growth, proliferation, and differentiation would be less impaired.

The Quest for Targets Executing MYC-Dependent Cell Transformation

PubMed Central

Hartl, Markus

2016-01-01

MYC represents a transcription factor with oncogenic potential converting multiple cellular signals into a broad transcriptional response, thereby controlling the expression of numerous protein-coding and non-coding RNAs important for cell proliferation, metabolism, differentiation, and apoptosis. Constitutive activation of MYC leads to neoplastic cell transformation, and deregulated MYC alleles are frequently observed in many human cancer cell types. Multiple approaches have been performed to isolate genes differentially expressed in cells containing aberrantly activated MYC proteins leading to the identification of thousands of putative targets. Functional analyses of genes differentially expressed in MYC-transformed cells had revealed that so far more than 40 upregulated or downregulated MYC targets are actively involved in cell transformation or tumorigenesis. However, further systematic and selective approaches are required for determination of the known or yet unidentified targets responsible for processing the oncogenic MYC program. The search for critical targets in MYC-dependent tumor cells is exacerbated by the fact that during tumor development, cancer cells progressively evolve in a multistep process, thereby acquiring their characteristic features in an additive manner. Functional expression cloning, combinatorial gene expression, and appropriate in vivo tests could represent adequate tools for dissecting the complex scenario of MYC-specified cell transformation. In this context, the central goal is to identify a minimal set of targets that suffices to phenocopy oncogenic MYC. Recently developed genomic editing tools could be employed to confirm the requirement of crucial transformation-associated targets. Knowledge about essential MYC-regulated genes is beneficial to expedite the development of specific inhibitors to interfere with growth and viability of human tumor cells in which MYC is aberrantly activated. Approaches based on the principle of synthetic lethality using MYC-overexpressing cancer cells and chemical or RNAi libraries have been employed to search for novel anticancer drugs, also leading to the identification of several druggable targets. Targeting oncogenic MYC effector genes instead of MYC may lead to compounds with higher specificities and less side effects. This class of drugs could also display a wider pharmaceutical window because physiological functions of MYC, which are important for normal cell growth, proliferation, and differentiation would be less impaired. PMID:27313991

Detection and volume estimation of embolic air in the middle cerebral artery using transcranial Doppler sonography.

PubMed

Bunegin, L; Wahl, D; Albin, M S

1994-03-01

Cerebral embolism has been implicated in the development of cognitive and neurological deficits following bypass surgery. This study proposes methodology for estimating cerebral air embolus volume using transcranial Doppler sonography. Transcranial Doppler audio signals of air bubbles in the middle cerebral artery obtained from in vivo experiments were subjected to a fast-Fourier transform analysis. Audio segments when no air was present as well as artifact resulting from electrocautery and sensor movement were also subjected to fast-Fourier transform analysis. Spectra were compared, and frequency and power differences were noted and used for development of audio band-pass filters for isolation of frequencies associated with air emboli. In a bench model of the middle cerebral artery circulation, repetitive injections of various air volumes between 0.5 and 500 microL were made. Transcranial Doppler audio output was band-pass filtered, acquired digitally, then subjected to a fast-Fourier transform power spectrum analysis and power spectrum integration. A linear least-squares correlation was performed on the data. Fast-Fourier transform analysis of audio segments indicated that frequencies between 250 and 500 Hz are consistently dominant in the spectrum when air emboli are present. Background frequencies appear to be below 240 Hz, and artifact resulting from sensor movement and electrocautery appears to be below 300 Hz. Data from the middle cerebral artery model filtered through a 307- to 450-Hz band-pass filter yielded a linear relation between emboli volume and the integrated value of the power spectrum near 40 microL. Detection of emboli less than 0.5 microL was inconsistent, and embolus volumes greater than 40 microL were indistinguishable from one another. The preliminary technique described in this study may represent a starting point from which automated detection and volume estimation of cerebral emboli might be approached.

Registration of organs with sliding interfaces and changing topologies

NASA Astrophysics Data System (ADS)

Berendsen, Floris F.; Kotte, Alexis N. T. J.; Viergever, Max A.; Pluim, Josien P. W.

2014-03-01

Smoothness and continuity assumptions on the deformation field in deformable image registration do not hold for applications where the imaged objects have sliding interfaces. Recent extensions to deformable image registration that accommodate for sliding motion of organs are limited to sliding motion along approximately planar surfaces or cannot model sliding that changes the topological configuration in case of multiple organs. We propose a new extension to free-form image registration that is not limited in this way. Our method uses a transformation model that consists of uniform B-spline transformations for each organ region separately, which is based on segmentation of one image. Since this model can create overlapping regions or gaps between regions, we introduce a penalty term that minimizes this undesired effect. The penalty term acts on the surfaces of the organ regions and is optimized simultaneously with the image similarity. To evaluate our method registrations were performed on publicly available inhale-exhale CT scans for which performances of other methods are known. Target registration errors are computed on dense landmark sets that are available with these datasets. On these data our method outperforms the other methods in terms of target registration error and, where applicable, also in terms of overlap and gap volumes. The approximation of the other methods of sliding motion along planar surfaces is reasonably well suited for the motion present in the lung data. The ability of our method to handle sliding along curved boundaries and for changing region topology configurations was demonstrated on synthetic images.

An augmented parametric response map with consideration of image registration error: towards guidance of locally adaptive radiotherapy

NASA Astrophysics Data System (ADS)

Lausch, Anthony; Chen, Jeff; Ward, Aaron D.; Gaede, Stewart; Lee, Ting-Yim; Wong, Eugene

2014-11-01

Parametric response map (PRM) analysis is a voxel-wise technique for predicting overall treatment outcome, which shows promise as a tool for guiding personalized locally adaptive radiotherapy (RT). However, image registration error (IRE) introduces uncertainty into this analysis which may limit its use for guiding RT. Here we extend the PRM method to include an IRE-related PRM analysis confidence interval and also incorporate multiple graded classification thresholds to facilitate visualization. A Gaussian IRE model was used to compute an expected value and confidence interval for PRM analysis. The augmented PRM (A-PRM) was evaluated using CT-perfusion functional image data from patients treated with RT for glioma and hepatocellular carcinoma. Known rigid IREs were simulated by applying one thousand different rigid transformations to each image set. PRM and A-PRM analyses of the transformed images were then compared to analyses of the original images (ground truth) in order to investigate the two methods in the presence of controlled IRE. The A-PRM was shown to help visualize and quantify IRE-related analysis uncertainty. The use of multiple graded classification thresholds also provided additional contextual information which could be useful for visually identifying adaptive RT targets (e.g. sub-volume boosts). The A-PRM should facilitate reliable PRM guided adaptive RT by allowing the user to identify if a patient’s unique IRE-related PRM analysis uncertainty has the potential to influence target delineation.

Targets of vascular protection in acute ischemic stroke differ in type 2 diabetes

PubMed Central

Kelly-Cobbs, Aisha I.; Prakash, Roshini; Li, Weiguo; Pillai, Bindu; Hafez, Sherif; Coucha, Maha; Johnson, Maribeth H.; Ogbi, Safia N.; Fagan, Susan C.

2013-01-01

Hemorrhagic transformation is an important complication of acute ischemic stroke, particularly in diabetic patients receiving thrombolytic treatment with tissue plasminogen activator, the only approved drug for the treatment of acute ischemic stroke. The objective of the present study was to determine the effects of acute manipulation of potential targets for vascular protection [i.e., NF-κB, peroxynitrite, and matrix metalloproteinases (MMPs)] on vascular injury and functional outcome in a diabetic model of cerebral ischemia. Ischemia was induced by middle cerebral artery occlusion in control and type 2 diabetic Goto-Kakizaki rats. Treatment groups received a single dose of the peroxynitrite decomposition catalyst 5,10,15,20-tetrakis(4-sulfonatophenyl)prophyrinato iron (III), the nonspecific NF-κB inhibitor curcumin, or the broad-spectrum MMP inhibitor minocycline at reperfusion. Poststroke infarct volume, edema, hemorrhage, neurological deficits, and MMP-9 activity were evaluated. All acute treatments reduced MMP-9 and hemorrhagic transformation in diabetic groups. In addition, acute curcumin and minocycline therapy reduced edema in these animals. Improved neurological function was observed in varying degrees with treatment, as indicated by beam-walk performance, modified Bederson scores, and grip strength; however, infarct size was similar to untreated diabetic animals. In control animals, all treatments reduced MMP-9 activity, yet bleeding was not improved. Neuroprotection was only conferred by curcumin and minocycline. Uncovering the underlying mechanisms contributing to the success of acute therapy in diabetes will advance tailored stroke therapies. PMID:23335797

miR-24 and miR-122 Negatively Regulate the Transforming Growth Factor-β/Smad Signaling Pathway in Skeletal Muscle Fibrosis.

PubMed

Sun, Yaying; Wang, Hui; Li, Yan; Liu, Shaohua; Chen, Jiwu; Ying, Hao

2018-06-01

Fibrosis is common after skeletal muscle injury, undermining tissue regeneration and function. The mechanism underlying skeletal muscle fibrosis remains unveiled. Transforming growth factor-β/Smad signaling pathway is supposed to play a pivotal role. However, how microRNAs interact with transforming growth factor-β/Smad-related muscle fibrosis remains unclear. We showed that microRNA (miR)-24-3p and miR-122-5p declined in skeletal muscle fibrosis, which was a consequence of transforming growth factor-β. Upregulating Smad4 suppressed two microRNAs, whereas inhibiting Smad4 elevated microRNAs. Luciferase reporter assay and chromatin immunoprecipitation confirmed that Smad4 directly inhibited two microRNAs. On the other hand, overexpression of these two miRs retarded fibrotic process. We further identified that Smad2 was a direct target of miR-24-3p, whereas miR-122-5p targeted transforming growth factor-β receptor-II. Both targets were important participants in transforming growth factor-β/Smad signaling. Taken together, a positive feedback loop in transforming growth factor-β/Smad4 signaling pathway in skeletal muscle fibrosis was identified. Transforming growth factor-β/Smad axis could be downregulated by microRNAs. This effect, however, was suppressed by Smad4, the downstream of transforming growth factor-β. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Anomalous expansion of Nb nanowires in a NiTi matrix under high pressure

DOE PAGES

Yu, Cun; Ren, Yang; Cui, Lishan; ...

2016-10-17

Under high pressure, materials usually shrink during compression as described by an equation of state. Here, we present the anomalous volume expansion behavior of a one-dimensional Nb nanowire embedded in a NiTi transforming matrix, while the matrix undergoes a pressure-induced martensitic transformation. The Nb volume expansion depends on the NiTi transition pressure range from the matrix, which is controlled by the shear strain induced by different pressure transmitting media. The transformation-induced interfacial stresses between Nb and NiTi may play a major role in this anomaly. In conclusion, our discovery sheds new light on the nano-interfacial effect on mechanical anomalies inmore » heterogeneous systems during a pressure-induced phase transition.« less

Statistical Mechanical Proof of the Second Law of Thermodynamics based on Volume Entropy

NASA Astrophysics Data System (ADS)

Campisi, Michele

2007-10-01

As pointed out in [M. Campisi. Stud. Hist. Phil. M. P. 36 (2005) 275-290] the volume entropy (that is the logarithm of the volume of phase space enclosed by the constant energy hyper-surface) provides a good mechanical analogue of thermodynamic entropy because it satisfies the heat theorem and it is an adiabatic invariant. This property explains the ``equal'' sign in Clausius principle (Sf>=Si) in a purely mechanical way and suggests that the volume entropy might explain the ``larger than'' sign (i.e. the Law of Entropy Increase) if non adiabatic transformations were considered. Based on the principles of quantum mechanics here we prove that, provided the initial equilibrium satisfy the natural condition of decreasing ordering of probabilities, the expectation value of the volume entropy cannot decrease for arbitrary transformations performed by some external sources of work on a insulated system. This can be regarded as a rigorous quantum mechanical proof of the Second Law.

Feasibility Study on Fully Automatic High Quality Translation: Volume II. Final Technical Report.

ERIC Educational Resources Information Center

Lehmann, Winifred P.; Stachowitz, Rolf

This second volume of a two-volume report on a fully automatic high quality translation (FAHQT) contains relevant papers contributed by specialists on the topic of machine translation. The papers presented here cover such topics as syntactical analysis in transformational grammar and in machine translation, lexical features in translation and…

DOE Office of Scientific and Technical Information (OSTI.GOV)

Avkshtol, V; Tanny, S; Reddy, K

Purpose: Stereotactic radiation therapy (SRT) provides an excellent alternative to embolization and surgical excision for the management of appropriately selected cerebral arteriovenous malformations (AVMs). The currently accepted standard for delineating AVMs is planar digital subtraction angiography (DSA). DSA can be used to acquire a 3D data set that preserves osseous structures (3D-DA) at the time of the angiography for SRT planning. Magnetic resonance imaging (MRI) provides an alternative noninvasive method of visualizing the AVM nidus with comparable spatial resolution. We utilized 3D-DA and T1 post-contrast MRI data to evaluate the differences in SRT target volumes. Methods: Four patients underwent 3D-DAmore » and high-resolution MRI. 3D T1 post-contrast images were obtained in all three reconstruction planes. A planning CT was fused with MRI and 3D-DA data sets. The AVMs were contoured utilizing one of the image sets at a time. Target volume, centroid, and maximum and minimum dimensions were analyzed for each patient. Results: Targets delineated using post-contrast MRI demonstrated a larger mean volume. AVMs >2 cc were found to have a larger difference between MRI and 3D-DA volumes. Larger AVMs also demonstrated a smaller relative uncertainty in contour centroid position (1 mm). AVM targets <2 cc had smaller absolute differences in volume, but larger differences in contour centroid position (2.5 mm). MRI targets demonstrated a more irregular shape compared to 3D-DA targets. Conclusions: Our preliminary data supports the use of MRI alone to delineate AVM targets >2 cc. The greater centroid stability for AVMs >2 cc ensures accurate target localization during image fusion. The larger MRI target volumes did not result in prohibitively greater volumes of normal brain tissue receiving the prescription dose. The larger centroid instability for AVMs <2 cc precludes the use of MRI alone for target delineation. We recommend incorporating a 3D-DA for these patients.« less

Single-Isocenter Multiple-Target Stereotactic Radiosurgery: Risk of Compromised Coverage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Roper, Justin, E-mail: justin.roper@emory.edu; Department of Biostatistics and Bioinformatics, Winship Cancer Institute of Emory University, Atlanta, Georgia; Chanyavanich, Vorakarn

2015-11-01

Purpose: To determine the dosimetric effects of rotational errors on target coverage using volumetric modulated arc therapy (VMAT) for multitarget stereotactic radiosurgery (SRS). Methods and Materials: This retrospective study included 50 SRS cases, each with 2 intracranial planning target volumes (PTVs). Both PTVs were planned for simultaneous treatment to 21 Gy using a single-isocenter, noncoplanar VMAT SRS technique. Rotational errors of 0.5°, 1.0°, and 2.0° were simulated about all axes. The dose to 95% of the PTV (D95) and the volume covered by 95% of the prescribed dose (V95) were evaluated using multivariate analysis to determine how PTV coverage was relatedmore » to PTV volume, PTV separation, and rotational error. Results: At 0.5° rotational error, D95 values and V95 coverage rates were ≥95% in all cases. For rotational errors of 1.0°, 7% of targets had D95 and V95 values <95%. Coverage worsened substantially when the rotational error increased to 2.0°: D95 and V95 values were >95% for only 63% of the targets. Multivariate analysis showed that PTV volume and distance to isocenter were strong predictors of target coverage. Conclusions: The effects of rotational errors on target coverage were studied across a broad range of SRS cases. In general, the risk of compromised coverage increased with decreasing target volume, increasing rotational error and increasing distance between targets. Multivariate regression models from this study may be used to quantify the dosimetric effects of rotational errors on target coverage given patient-specific input parameters of PTV volume and distance to isocenter.« less

Simulating the Effect of Spectroscopic MRI as a Metric for Radiation Therapy Planning in Patients with Glioblastoma

PubMed Central

Cordova, J. Scott; Kandula, Shravan; Gurbani, Saumya; Zhong, Jim; Tejani, Mital; Kayode, Oluwatosin; Patel, Kirtesh; Prabhu, Roshan; Schreibmann, Eduard; Crocker, Ian; Holder, Chad A.; Shim, Hyunsuk; Shu, Hui-Kuo

2017-01-01

Due to glioblastoma’s infiltrative nature, an optimal radiation therapy (RT) plan requires targeting infiltration not identified by anatomical magnetic resonance imaging (MRI). Here, high-resolution, whole-brain spectroscopic MRI (sMRI) is used to describe tumor infiltration alongside anatomical MRI and simulate the degree to which it modifies RT target planning. In 11 patients with glioblastoma, data from preRT sMRI scans were processed to give high-resolution, whole-brain metabolite maps normalized by contralateral white matter. Maps depicting choline to N-Acetylaspartate (Cho/NAA) ratios were registered to contrast-enhanced T1-weighted RT planning MRI for each patient. Volumes depicting metabolic abnormalities (1.5−, 1.75−, and 2.0-fold increases in Cho/NAA ratios) were compared with conventional target volumes and contrast-enhancing tumor at recurrence. sMRI-modified RT plans were generated to evaluate target volume coverage and organ-at-risk dose constraints. Conventional clinical target volumes and Cho/NAA abnormalities identified significantly different regions of microscopic infiltration with substantial Cho/NAA abnormalities falling outside of the conventional 60 Gy isodose line (41.1, 22.2, and 12.7 cm3, respectively). Clinical target volumes using Cho/NAA thresholds exhibited significantly higher coverage of contrast enhancement at recurrence on average (92.4%, 90.5%, and 88.6%, respectively) than conventional plans (82.5%). sMRI-based plans targeting tumor infiltration met planning objectives in all cases with no significant change in target coverage. In 2 cases, the sMRI-modified plan exhibited better coverage of contrast-enhancing tumor at recurrence than the original plan. Integration of the high-resolution, whole-brain sMRI into RT planning is feasible, resulting in RT target volumes that can effectively target tumor infiltration while adhering to conventional constraints. PMID:28105468

Image registration via optimization over disjoint image regions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pitts, Todd; Hathaway, Simon; Karelitz, David B.

Technologies pertaining to registering a target image with a base image are described. In a general embodiment, the base image is selected from a set of images, and the target image is an image in the set of images that is to be registered to the base image. A set of disjoint regions of the target image is selected, and a transform to be applied to the target image is computed based on the optimization of a metric over the selected set of disjoint regions. The transform is applied to the target image so as to register the target imagemore » with the base image.« less

A difference tracking algorithm based on discrete sine transform

NASA Astrophysics Data System (ADS)

Liu, HaoPeng; Yao, Yong; Lei, HeBing; Wu, HaoKun

2018-04-01

Target tracking is an important field of computer vision. The template matching tracking algorithm based on squared difference matching (SSD) and standard correlation coefficient (NCC) matching is very sensitive to the gray change of image. When the brightness or gray change, the tracking algorithm will be affected by high-frequency information. Tracking accuracy is reduced, resulting in loss of tracking target. In this paper, a differential tracking algorithm based on discrete sine transform is proposed to reduce the influence of image gray or brightness change. The algorithm that combines the discrete sine transform and the difference algorithm maps the target image into a image digital sequence. The Kalman filter predicts the target position. Using the Hamming distance determines the degree of similarity between the target and the template. The window closest to the template is determined the target to be tracked. The target to be tracked updates the template. Based on the above achieve target tracking. The algorithm is tested in this paper. Compared with SSD and NCC template matching algorithms, the algorithm tracks target stably when image gray or brightness change. And the tracking speed can meet the read-time requirement.

A new method for detecting small and dim targets in starry background

NASA Astrophysics Data System (ADS)

Yao, Rui; Zhang, Yanning; Jiang, Lei

2011-08-01

Small visible optical space targets detection is one of the key issues in the research of long-range early warning and space debris surveillance. The SNR(Signal to Noise Ratio) of the target is very low because of the self influence of image device. Random noise and background movement also increase the difficulty of target detection. In order to detect small visible optical space targets effectively and rapidly, we bring up a novel detecting method based on statistic theory. Firstly, we get a reasonable statistical model of visible optical space image. Secondly, we extract SIFT(Scale-Invariant Feature Transform) feature of the image frames, and calculate the transform relationship, then use the transform relationship to compensate whole visual field's movement. Thirdly, the influence of star was wiped off by using interframe difference method. We find segmentation threshold to differentiate candidate targets and noise by using OTSU method. Finally, we calculate statistical quantity to judge whether there is the target for every pixel position in the image. Theory analysis shows the relationship of false alarm probability and detection probability at different SNR. The experiment result shows that this method could detect target efficiently, even the target passing through stars.

Transform Decoding of Reed-Solomon Codes. Volume II. Logical Design and Implementation.

DTIC Science & Technology

1982-11-01

i A. nE aib’ = a(bJ) ; j=0, 1, ... , n-l (2-8) i=01 Similarly, the inverse transform is obtained by interpolation of the polynomial a(z) from its n...with the transform so that either a forward or an inverse transform may be used to encode. The only requirement is that tie reverse of the encoding... inverse transform of the received sequence is the polynomial sum r(z) = e(z) + a(z), where e(z) is the inverse transform of the error polynomial E(z), and a

Dosimetric comparison of photon and proton treatment techniques for chondrosarcoma of thoracic spine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yadav, Poonam, E-mail: yadav@humonc.wisc.edu; Department of Medical Physics, University of Wisconsin, Madison, WI; University of Wisconsin Riverview Cancer Center, Wisconsin Rapids, WI

2013-10-01

Chondrosarcomas are relatively radiotherapy resistant, and also delivering high radiation doses is not feasible owing to anatomic constraints. In this study, the feasibility of helical tomotherapy for treatment of chondrosarcoma of thoracic spine is explored and compared with other available photon and proton radiotherapy techniques in the clinical setting. A patient was treated for high-grade chondrosarcoma of the thoracic spine using tomotherapy. Retrospectively, the tomotherapy plan was compared with intensity-modulated radiation therapy, dynamic arc photon therapy, and proton therapy. Two primary comparisons were made: (1) comparison of normal tissue sparing with comparable target volume coverage (plan-1), and (2) comparison ofmore » target volume coverage with a constrained maximum dose to the cord center (plan-2). With constrained target volume coverage, proton plans were found to yield lower mean doses for all organs at risk (spinal cord, esophagus, heart, and both lungs). Tomotherapy planning resulted in the lowest mean dose to all organs at risk amongst photon-based methods. For cord dose constrained plans, the static-field intensity-modulated radiation therapy and dynamic arc plans resulted target underdosing in 20% and 12% of planning target volume2 volumes, respectively, whereas both proton and tomotherapy plans provided clinically acceptable target volume coverage with no portion of planning target volume2 receiving less than 90% of the prescribed dose. Tomotherapy plans are comparable to proton plans and produce superior results compared with other photon modalities. This feasibility study suggests that tomotherapy is an attractive alternative to proton radiotherapy for delivering high doses to lesions in the thoracic spine.« less

Extending unbiased stereology of brain ultrastructure to three-dimensional volumes

NASA Technical Reports Server (NTRS)

Fiala, J. C.; Harris, K. M.; Koslow, S. H. (Principal Investigator)

2001-01-01

OBJECTIVE: Analysis of brain ultrastructure is needed to reveal how neurons communicate with one another via synapses and how disease processes alter this communication. In the past, such analyses have usually been based on single or paired sections obtained by electron microscopy. Reconstruction from multiple serial sections provides a much needed, richer representation of the three-dimensional organization of the brain. This paper introduces a new reconstruction system and new methods for analyzing in three dimensions the location and ultrastructure of neuronal components, such as synapses, which are distributed non-randomly throughout the brain. DESIGN AND MEASUREMENTS: Volumes are reconstructed by defining transformations that align the entire area of adjacent sections. Whole-field alignment requires rotation, translation, skew, scaling, and second-order nonlinear deformations. Such transformations are implemented by a linear combination of bivariate polynomials. Computer software for generating transformations based on user input is described. Stereological techniques for assessing structural distributions in reconstructed volumes are the unbiased bricking, disector, unbiased ratio, and per-length counting techniques. A new general method, the fractional counter, is also described. This unbiased technique relies on the counting of fractions of objects contained in a test volume. A volume of brain tissue from stratum radiatum of hippocampal area CA1 is reconstructed and analyzed for synaptic density to demonstrate and compare the techniques. RESULTS AND CONCLUSIONS: Reconstruction makes practicable volume-oriented analysis of ultrastructure using such techniques as the unbiased bricking and fractional counter methods. These analysis methods are less sensitive to the section-to-section variations in counts and section thickness, factors that contribute to the inaccuracy of other stereological methods. In addition, volume reconstruction facilitates visualization and modeling of structures and analysis of three-dimensional relationships such as synaptic connectivity.

Effect of Ni Addition on Bainite Transformation and Properties in a 2000 MPa Grade Ultrahigh Strength Bainitic Steel

NASA Astrophysics Data System (ADS)

Tian, Junyu; Xu, Guang; Jiang, Zhengyi; Hu, Haijiang; Zhou, Mingxing

2018-05-01

The effects of Nickle (Ni) addition on bainitic transformation and property of ultrahigh strength bainitic steels are investigated by three austempering processes. The results indicate that Ni addition hinders the isothermal bainite transformation kinetics, and decreases the volume fraction of bainite due to the decrease of chemical driving force for nucleation and growth of bainite transformation. Moreover, the product of tensile strength and total elongation (PSE) of high carbon bainitic steels decreases with Ni addition at higher austempering temperatures (220 and 250 °C), while it shows no significant difference at lower austempering temperature (200 °C). For the same steel (Ni-free or Ni-added steel), the amounts of bainite and RA firstly increase and then decrease with the increase of the austempering temperature, resulting in the highest PSE in the sample austempered at temperature of 220 °C. In addition, the effects of austempering time on bainite amount and property of high carbon bainitic steels are also analyzed. It indicates that in a given transformation time range of 30 h, more volume of bainite and better mechanical property in high carbon bainitic steels can be obtained by increasing the isothermal transformation time.

Research to improve the accuracy of determining the stroke volume of an artificial ventricle using the wavelet transform

NASA Astrophysics Data System (ADS)

Grad, Leszek; Murawski, Krzysztof; Sulej, Wojciech

2017-08-01

In the article we presented results obtained during research, which are the continuation of work on the use of artificial neural networks to determine the relationship between the view of the membrane and the stroke volume of the blood chamber of the mechanical prosthetic heart. The purpose of the research was to increase the accuracy of determining the blood chamber volume. Therefore, the study was focused on the technique of the features that the image extraction gives. During research we used the wavelet transform. The achieved results were compared to the results obtained by other previous methods. Tests were conducted on the same mechanical prosthetic heart model used in previous experiments.

Three-dimensional microscopic tomographic imagings of the cataract in a human lens in vivo

NASA Astrophysics Data System (ADS)

Masters, Barry R.

1998-10-01

The problem of three-dimensional visualization of a human lens in vivo has been solved by a technique of volume rendering a transformed series of 60 rotated Scheimpflug (a dual slit reflected light microscope) digital images. The data set was obtained by rotating the Scheimpflug camera about the optic axis of the lens in 3 degree increments. The transformed set of optical sections were first aligned to correct for small eye movements, and then rendered into a volume reconstruction with volume rendering computer graphics techniques. To help visualize the distribution of lens opacities (cataracts) in the living, human lens the intensity of light scattering was pseudocolor coded and the cataract opacities were displayed as a movie.

Heat transfer comparison of nanofluid filled transformer and traditional oil-immersed transformer

NASA Astrophysics Data System (ADS)

Zhang, Yunpeng; Ho, Siu-lau; Fu, Weinong

2018-05-01

Dispersing nanoparticles with high thermal conductivity into transformer oil is an innovative approach to improve the thermal performance of traditional oil-immersed transformers. This mixture, also known as nanofluid, has shown the potential in practical application through experimental measurements. This paper presents the comparisons of nanofluid filled transformer and traditional oil-immersed transformer in terms of their computational fluid dynamics (CFD) solutions from the perspective of optimal design. Thermal performance of transformers with the same parameters except coolants is compared. A further comparison on heat transfer then is made after minimizing the oil volume and maximum temperature-rise of these two transformers. Adaptive multi-objective optimization method is employed to tackle this optimization problem.

A dual selection based, targeted gene replacement tool for Magnaporthe grisea and Fusarium oxysporum.

PubMed

Khang, Chang Hyun; Park, Sook-Young; Lee, Yong-Hwan; Kang, Seogchan

2005-06-01

Rapid progress in fungal genome sequencing presents many new opportunities for functional genomic analysis of fungal biology through the systematic mutagenesis of the genes identified through sequencing. However, the lack of efficient tools for targeted gene replacement is a limiting factor for fungal functional genomics, as it often necessitates the screening of a large number of transformants to identify the desired mutant. We developed an efficient method of gene replacement and evaluated factors affecting the efficiency of this method using two plant pathogenic fungi, Magnaporthe grisea and Fusarium oxysporum. This method is based on Agrobacterium tumefaciens-mediated transformation with a mutant allele of the target gene flanked by the herpes simplex virus thymidine kinase (HSVtk) gene as a conditional negative selection marker against ectopic transformants. The HSVtk gene product converts 5-fluoro-2'-deoxyuridine to a compound toxic to diverse fungi. Because ectopic transformants express HSVtk, while gene replacement mutants lack HSVtk, growing transformants on a medium amended with 5-fluoro-2'-deoxyuridine facilitates the identification of targeted mutants by counter-selecting against ectopic transformants. In addition to M. grisea and F. oxysporum, the method and associated vectors are likely to be applicable to manipulating genes in a broad spectrum of fungi, thus potentially serving as an efficient, universal functional genomic tool for harnessing the growing body of fungal genome sequence data to study fungal biology.

Andrei Sakharov Prize

NASA Astrophysics Data System (ADS)

Xu, Liangying

2008-04-01

Ever since my youth, the writings of Einstein had always enlightened my life. However, I later began to follow Marxism and threw myself into the Chinese revolution. Yet, ironically, after the victory of the revolution I myself became a target of the revolutionary dictatorship. Started from 1962 I collected, edited and translated ``Collected Works of Einstein'' in the countryside. Fourteen years later the three-volume collected works were published in China, which created immense impacts to Chinese intellectuals. It was Einstein's thoughts on human rights and democracy that awakened me. Since then I have devoted myself to the fight for human rights and to the cause of democratic enlightenment in China. My goal is to transform an autocratic China that tramples human rights into a democratic and free modern China that respects human rights.

Transforming Aggregate Object-Oriented Formal Specifications to Code

DTIC Science & Technology

1999-03-01

integration issues associated with a formal-based software transformation system, such as the source specification, the problem space architecture , design architecture ... design transforms, and target software transforms. Software is critical in today’s Air Force, yet its specification, design, and development

The HALT Polycystic Kidney Disease Trials – Analysis of baseline parameters

PubMed Central

Torres, Vicente E.; Chapman, Arlene B.; Perrone, Ronald D.; Bae, K. Ty; Abebe, Kaleab Z.; Bost, James E.; Miskulin, Dana C.; Steinman, Theodore I.; Braun, William; Winklhofer, Franz T.; Hogan, Marie C.; Oskoui, Frederic Rahbari; Kelleher, Cass; Masoumi, Amirali; Glockner, James; Halin, Neil J; Martin, Diego; Remer, Erick; Patel, Nayana.; Pedrosa, Ivan; Wetzel, Louis H.; Thompson, Paul A.; Miller, J. Philip; Meyers, Catherine M.; Schrier, Robert W.

2013-01-01

HALT-PKD consists of two randomized trials comparing treatment with an angiotensin converting inhibitor (ACEI)-angiotensin receptor blocker (ARB) combination vs ACEI alone and standard vs low blood pressure target in Study A (eGFR >60 ml/min/1.73 m2) and ACEI-ARB vs ACEI alone in Study B (eGFR 25-60 ml/min/1.73 m2). It includes the largest cohort of systematically studied ADPKD patients (558 A and 486 B) to date. We used correlation and multiple regression cross-sectional analyses to ascertain associations of baseline parameters with total kidney (TKV) and liver (TLV) or liver cyst (LCV) volumes measured by MRI in Study A and with eGFR in both studies. Lower eGFR and higher natural log transformed urine albumin excretion are independently associated with larger natural log transformed TKV adjusted for height (HtTKV). Higher BSA is independently associated with higher ln(HtTKV) and lower eGFR. Men have larger HtTKV and smaller LCV than women. A weak correlation was found between ln(HtTKV) and ln(HtTLV) or ln(LCV) in women only. Women have higher urine aldosterone excretions and lower plasma potassium levels. In summary, this analysis 1) confirms a strong association between renal volume and functional parameters, 2) shows that gender and other factors differentially affect the development of polycystic disease in the kidney and liver, and 3) suggests an association between anthropomorphic measures reflecting preand/or post-natal growth and the severity of the disease. PMID:22205355

Reperfusion-Associated Hemorrhagic Transformation in SHR Rats

PubMed Central

Henning, Erica C.; Latour, Lawrence L.; Hallenbeck, John M.; Warach, Steven

2016-01-01

Background and Purpose Symptomatic hemorrhagic transformation (HT) is the most important complicating factor after treatment with intravenous tissue plasminogen activator. In this study, we used multimodal magnetic resonance imaging to investigate the incidence and severity of reperfusion-based HT in spontaneously hypertensive rats after ischemia/reperfusion. Methods Twenty male spontaneously hypertensive rats were subjected to 30 minutes of middle cerebral artery occlusion via the suture model. Diffusion-weighted, T2-weighted, and gradient-echo imaging were performed on days 1, 2, 3, 4, and 7 for longitudinal evaluation of lesion evolution, vasogenic edema, and HT, respectively. Findings on gradient-echo images were classified according to the severity of hemorrhage: no HT; punctate or small petechial hemorrhage (HI-1); confluent petechial hemorrhage (HI-2); hematoma with absent/mild space-occupying effect (PH-1, ≤30% lesion volume); and hematoma with significant space-occupying effect and potential perihematomal edema (PH-2, >30% lesion volume). Histopathologic evaluation of HT was performed after final imaging for comparison with magnetic resonance imaging results. Results Final hemorrhage scores based on severity were as follows: HI-1 23.1%, HI-2 30.8%, PH-1 30.8%, and PH-2 15.4%. Similar to clinical observations, only PH-2 was associated with neurologic deterioration and associated weight loss. Conclusions This model has a high incidence of parenchymal hematomas (46.2%) and therefore is appropriate for the evaluation of novel therapeutics targeting blood-brain barrier integrity and the reduction of symptomatic HT events (PH-2), as well as those potentially “at risk” for neurologic deterioration (PH-1). PMID:18757286

Folktale Themes and Activities for Children. Volume 2: Trickster and Transformation Tales. Learning through Folklore Series.

ERIC Educational Resources Information Center

Kraus, Anne Marie

This companion volume to "Folktale Themes Volume 1: Pourquoi Tales," shows educators how to use folktales to provide meaningful, educational experiences for children. This book provides a complete package using folktales in the classroom--activity pages, teaching ideas, story themes, and an annotated bibliography of further reading for a…

Application of methylation in improving plasmid transformation into Helicobacter pylori.

PubMed

Zhao, Huilin; Xu, Linlin; Rong, Qianyu; Xu, Zheng; Ding, Yunfei; Zhang, Ying; Wu, Yulong; Li, Boqing; Ji, Xiaofei

2018-05-23

Helicobacter pylori is an important gastrointestinal pathogen. Its strains possess different levels of powerful restriction modification systems, which are significant barriers to genetic tools used for studying the role of functional genes in its pathogenesis. Methylating vectors in vitro was reported as an alternative to overcome this barrier in several bacteria. In this study we used two H. pylori-E. coli shuttle plasmids and several single/double-crossover homologous recombination gene-targeting plasmids, to test the role of methylation in H. pylori transformation. According to our results, transformants could be obtained only after shuttle plasmids were methylated before transformation. It is helpful in gene complementation and over-expression although at a low frequency. The frequency of gene-targeting transformation was also increased after methylation, especially for the single-crossover recombination plasmids, the transformants of which could only be obtained after methylation. For the double-crossover recombination targeting plasmids, the initial yield of transformants was 0.3-0.8 × 10 2 CFUs per microgram plasmid DNA. With the help of methylation, the yield was increased to 0.4-1.3 × 10 2 CFUs per microgram plasmid DNA. These results suggest that in vitro methylation can improve H. pylori transformation by different plasmids, which will benefit the pathogenic mechanism research. Copyright © 2018. Published by Elsevier B.V.

Factors influencing the specific interaction of Neisseria gonorrhoeae with transforming DNA.

PubMed Central

Goodman, S D; Scocca, J J

1991-01-01

The specific interaction of transformable Neisseria gonorrhoeae with DNA depends on the recognition of specific 10-residue target sequences. The relative affinity for DNA between 3 and 17 kb in size appears to be linearly related to the frequency of targets on the segment and is unaffected by absolute size. The average frequency of targets in chromosomal DNA of N. gonorrhoeae appears to be approximately one per 1,000 bp. PMID:1909325

Improved target detection algorithm using Fukunaga-Koontz transform and distance classifier correlation filter

NASA Astrophysics Data System (ADS)

Bal, A.; Alam, M. S.; Aslan, M. S.

2006-05-01

Often sensor ego-motion or fast target movement causes the target to temporarily go out of the field-of-view leading to reappearing target detection problem in target tracking applications. Since the target goes out of the current frame and reenters at a later frame, the reentering location and variations in rotation, scale, and other 3D orientations of the target are not known thus complicating the detection algorithm has been developed using Fukunaga-Koontz Transform (FKT) and distance classifier correlation filter (DCCF). The detection algorithm uses target and background information, extracted from training samples, to detect possible candidate target images. The detected candidate target images are then introduced into the second algorithm, DCCF, called clutter rejection module, to determine the target coordinates are detected and tracking algorithm is initiated. The performance of the proposed FKT-DCCF based target detection algorithm has been tested using real-world forward looking infrared (FLIR) video sequences.

Hierarchical brain mapping via a generalized Dirichlet solution for mapping brain manifolds

NASA Astrophysics Data System (ADS)

Joshi, Sarang C.; Miller, Michael I.; Christensen, Gary E.; Banerjee, Ayan; Coogan, Tom; Grenander, Ulf

1995-08-01

In this paper we present a coarse-to-fine approach for the transformation of digital anatomical textbooks from the ideal to the individual that unifies the work on landmark deformations and volume based transformation. The Hierarchical approach is linked to the Biological problem itself, coming out of the various kinds of information which is provided by the anatomists. This information is in the form of points, lines, surfaces and sub-volumes corresponding to 0, 1, 2, and 3 dimensional sub-manifolds respectively. The algorithm is driven by these sub- manifolds. We follow the approach that the highest dimensional transformation is a result from the solution of a sequence of lower dimensional problems driven by successive refinements or partitions of the images into various Biologically meaningful sub-structures.

Infrared small target enhancement: grey level mapping based on improved sigmoid transformation and saliency histogram

NASA Astrophysics Data System (ADS)

Wan, Minjie; Gu, Guohua; Qian, Weixian; Ren, Kan; Chen, Qian

2018-06-01

Infrared (IR) small target enhancement plays a significant role in modern infrared search and track (IRST) systems and is the basic technique of target detection and tracking. In this paper, a coarse-to-fine grey level mapping method using improved sigmoid transformation and saliency histogram is designed to enhance IR small targets under different backgrounds. For the stage of rough enhancement, the intensity histogram is modified via an improved sigmoid function so as to narrow the regular intensity range of background as much as possible. For the part of further enhancement, a linear transformation is accomplished based on a saliency histogram constructed by averaging the cumulative saliency values provided by a saliency map. Compared with other typical methods, the presented method can achieve both better visual performances and quantitative evaluations.

Neurotechnology for intelligence analysts

NASA Astrophysics Data System (ADS)

Kruse, Amy A.; Boyd, Karen C.; Schulman, Joshua J.

2006-05-01

Geospatial Intelligence Analysts are currently faced with an enormous volume of imagery, only a fraction of which can be processed or reviewed in a timely operational manner. Computer-based target detection efforts have failed to yield the speed, flexibility and accuracy of the human visual system. Rather than focus solely on artificial systems, we hypothesize that the human visual system is still the best target detection apparatus currently in use, and with the addition of neuroscience-based measurement capabilities it can surpass the throughput of the unaided human severalfold. Using electroencephalography (EEG), Thorpe et al1 described a fast signal in the brain associated with the early detection of targets in static imagery using a Rapid Serial Visual Presentation (RSVP) paradigm. This finding suggests that it may be possible to extract target detection signals from complex imagery in real time utilizing non-invasive neurophysiological assessment tools. To transform this phenomenon into a capability for defense applications, the Defense Advanced Research Projects Agency (DARPA) currently is sponsoring an effort titled Neurotechnology for Intelligence Analysts (NIA). The vision of the NIA program is to revolutionize the way that analysts handle intelligence imagery, increasing both the throughput of imagery to the analyst and overall accuracy of the assessments. Successful development of a neurobiologically-based image triage system will enable image analysts to train more effectively and process imagery with greater speed and precision.

Applications of wavelets in interferometry and artificial vision

NASA Astrophysics Data System (ADS)

Escalona Z., Rafael A.

2001-08-01

In this paper we present a different point of view of phase measurements performed in interferometry, image processing and intelligent vision using Wavelet Transform. In standard and white-light interferometry, the phase function is retrieved by using phase-shifting, Fourier-Transform, cosinus-inversion and other known algorithms. Our novel technique presented here is faster, robust and shows excellent accuracy in phase determinations. Finally, in our second application, fringes are no more generate by some light interaction but result from the observation of adapted strip set patterns directly printed on the target of interest. The moving target is simply observed by a conventional vision system and usual phase computation algorithms are adapted to an image processing by wavelet transform, in order to sense target position and displacements with a high accuracy. In general, we have determined that wavelet transform presents properties of robustness, relative speed of calculus and very high accuracy in phase computations.

The impact of PET/CT scanning on the size of target volumes, radiation exposure of organs at risk, TCP and NTCP, in the radiotherapy planning of non-small cell lung cancer.

PubMed

Vojtíšek, Radovan; Mužík, Jan; Slampa, Pavel; Budíková, Marie; Hejsek, Jaroslav; Smolák, Petr; Ferda, Jiří; Fínek, Jindřich

2014-05-01

To compare radiotherapy plans made according to CT and PET/CT and to investigate the impact of changes in target volumes on tumour control probability (TCP), normal tissue complication probability (NTCP) and the impact of PET/CT on the staging and treatment strategy. Contemporary studies have proven that PET/CT attains higher sensitivity and specificity in the diagnosis of lung cancer and also leads to higher accuracy than CT alone in the process of target volume delineation in NSCLC. Between October 2009 and March 2012, 31 patients with locally advanced NSCLC, who had been referred to radical radiotherapy were involved in our study. They all underwent planning PET/CT examination. Then we carried out two separate delineations of target volumes and two radiotherapy plans and we compared the following parameters of those plans: staging, treatment purpose, the size of GTV and PTV and the exposure of organs at risk (OAR). TCP and NTCP were also compared. PET/CT information led to a significant decrease in the sizes of target volumes, which had the impact on the radiation exposure of OARs. The reduction of target volume sizes was not reflected in the significant increase of the TCP value. We found that there is a very strong direct linear relationship between all evaluated dosimetric parameters and NTCP values of all evaluated OARs. Our study found that the use of planning PET/CT in the radiotherapy planning of NSCLC has a crucial impact on the precise determination of target volumes, more precise staging of the disease and thus also on possible changes of treatment strategy.

Consistency in seroma contouring for partial breast radiotherapy: Impact of guidelines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wong, Elaine K.; Truong, Pauline T.; Kader, Hosam A.

2006-10-01

Purpose: Inconsistencies in contouring target structures can undermine the precision of conformal radiation therapy (RT) planning and compromise the validity of clinical trial results. This study evaluated the impact of guidelines on consistency in target volume contouring for partial breast RT planning. Methods and Materials: Guidelines for target volume definition for partial breast radiation therapy (PBRT) planning were developed by members of the steering committee for a pilot trial of PBRT using conformal external beam planning. In phase 1, delineation of the breast seroma in 5 early-stage breast cancer patients was independently performed by a 'trained' cohort of four radiationmore » oncologists who were provided with these guidelines and an 'untrained' cohort of four radiation oncologists who contoured without guidelines. Using automated planning software, the seroma target volume (STV) was expanded into a clinical target volume (CTV) and planning target volume (PTV) for each oncologist. Means and standard deviations were calculated, and two-tailed t tests were used to assess differences between the 'trained' and 'untrained' cohorts. In phase 2, all eight radiation oncologists were provided with the same contouring guidelines, and were asked to delineate the seroma in five new cases. Data were again analyzed to evaluate consistency between the two cohorts. Results: The 'untrained' cohort contoured larger seroma volumes and had larger CTVs and PTVs compared with the 'trained' cohort in three of five cases. When seroma contouring was performed after review of contouring guidelines, the differences in the STVs, CTVs, and PTVs were no longer statistically significant. Conclusion: Guidelines can improve consistency among radiation oncologists performing target volume delineation for PBRT planning.« less

Magnetic Resonance Lymphography-Guided Selective High-Dose Lymph Node Irradiation in Prostate Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meijer, Hanneke J.M., E-mail: H.Meijer@rther.umcn.nl; Debats, Oscar A.; Kunze-Busch, Martina

2012-01-01

Purpose: To demonstrate the feasibility of magnetic resonance lymphography (MRL) -guided delineation of a boost volume and an elective target volume for pelvic lymph node irradiation in patients with prostate cancer. The feasibility of irradiating these volumes with a high-dose boost to the MRL-positive lymph nodes in conjunction with irradiation of the prostate using intensity-modulated radiotherapy (IMRT) was also investigated. Methods and Materials: In 4 prostate cancer patients with a high risk of lymph node involvement but no enlarged lymph nodes on CT and/or MRI, MRL detected pathological lymph nodes in the pelvis. These lymph nodes were identified and delineatedmore » on a radiotherapy planning CT to create a boost volume. Based on the location of the MRL-positive lymph nodes, the standard elective pelvic target volume was individualized. An IMRT plan with a simultaneous integrated boost (SIB) was created with dose prescriptions of 42 Gy to the pelvic target volume, a boost to 60 Gy to the MRL-positive lymph nodes, and 72 Gy to the prostate. Results: All MRL-positive lymph nodes could be identified on the planning CT. This information could be used to delineate a boost volume and to individualize the pelvic target volume for elective irradiation. IMRT planning delivered highly acceptable radiotherapy plans with regard to the prescribed dose levels and the dose to the organs at risk (OARs). Conclusion: MRL can be used to select patients with limited lymph node involvement for pelvic radiotherapy. MRL-guided delineation of a boost volume and an elective pelvic target volume for selective high-dose lymph node irradiation with IMRT is feasible. Whether this approach will result in improved outcome for these patients needs to be investigated in further clinical studies.« less

[Comparison of SIB-IMRT treatment plans for upper esophageal carcinoma].

PubMed

Fu, Wei-hua; Wang, Lv-hua; Zhou, Zong-mei; Dai, Jian-rong; Hu, Yi-min

2003-06-01

To implement simultaneous integrated boost intensity-modulated radiotherapy(SIB-IMRT) plans for upper esophageal carcinoma and investigate the dose profiles of tumor and electively treated region and the dose to organs at risk (OARs). SIB-IMRT plans were designed for two patients with upper esophageal carcinoma. Two target volumes were predefined: PTV1, the target volume of the primary lesion, which was given to 67.2 Gy, and PTV2, the target volume of electively treated region, which was given to 50.4 Gy. With the same dose-volume constraints, but different beams arrangements (3, 5, 7, or 9 equispaced coplanar beams), four plans were generated. Indices, including dose distribution, dose volume histogram (DVH) and conformity index, were used for comparison of these plans. The plan with three intensity-modulated beams could produce good dose distribution for the two target volumes. The dose conformity to targets and the dose to OARs were improved as the beam number increased. The dose distributions in targets changed little when the beam number increased from 7 to 9. Five to seven intensity-modulated beams can produce desirable dose distributions for simultaneous integrated boost (SIB) treatment for upper esophageal carcinoma. The primary tumor can get higher equivalent dose by SIB treatments. It is easier and more efficient to design plans with equispaced coplanar beams. The efficacy of SIB-IMRT remains to be determined by the clinical outcome.

P04.02 Analysis of 18F-DOPA PET imaging for target volume definition in patients with recurrent glioblastoma treated with proton therapy

PubMed Central

Amelio, D.; Scartoni, D.; Palucci, A.; Vennarini, S.; Giacomelli, I.; Lemoine, S.; Donner, D.; Farace, P.; Chierichetti, F.; Amichetti, M.

2017-01-01

Abstract Introduction: Target volume definition is of critical relevance when re-irradiation is delivered and steep dose gradient irradiation techniques, such as proton therapy (PT), are employed. Aim of the study is to investigate the impact of 18F-DOPA on target volume contouring in recurrent glioblastoma (rGBM) patients (pts) undergoing re-irradiation with PT. MATERIAL AND METHODS: We investigated the differences in volume and relationship of magnetic resonance imaging (MRI)- vs. DOPA PET-derived gross tumor volumes (GTVs) of 14 rGBM pts re-irradiated with PT between January and November 2016. All pts had been previously treated with photon radiotherapy (60 Gy) with concomitant and adjuvant temozolomide. All the pts received morphological MRI with contrast enhancement medium administration and 18F-DOPA PET-CT study. We used the pathological distribution of 18F-DOPA in brain tissue to identify the so-called Biological Tumor Volume (BTV). Such areas were assessed using a tumor to normal brain ratio > 2. Moreover, any area of contrast enhancement on MRI was used to identify the MRI-based GTV (MRGTV). Definitive GTV included MRGTV plus BTV. Clinical target volume was generated by adding to GTV a 3-mm uniform margin manually corrected in proximity of anatomical barriers. CTV was expanded by 4 mm to create planning target volume. All pts received 36 GyRBE in 18 fractions. Mean values of differently delineated GTVs were compared each other by paired Student’s t-test; p < 0.05 was considered significant. To further compare MRGTV and BTV, the overlapping (MRGTV ^ BTV) and the composite (MRGTV U BTV) volumes were calculated, and a concordance index (CI) was defined as the ratio between the overlap and composite volumes. Results: MRGTV (mean 14.9 ± 14.5 cc) was larger than BTV (mean 10.9 ± 9.8 cc) although this difference was not statistically significant. The composite volume (mean 20.9 ± 14.7 cc) was significantly larger than each single volume (p < 0.006). The overlapping volume (mean 5.7 ± 3.3 cc) was quite small compared to each single volume and suggest that relevant part of MRIGTV is not covered by BTV as well as that relevant part of BTV is not covered by MRGTV. In line with such results we recorded also a low CI (mean 0.26 ± 0.2). The PT irradiation of PET-integrated target volumes provided a median progression-free survival (PFS) of 6 months, while the 6-month PFS rate was 57%; median survival after PT was 8.7 months, while 9-month survival rate was 60%. Conclusions: Target volume definition for rGBM undergoing PT re-irradiation may yield significantly differing results depending upon the imaging modality used for target contouring. Our data suggest that 18F-DOPA PET can detect relevant non-enhancing pathological areas outside the conventional MRGTV ultimately yielding to larger volumes to be irradiated. Influence on clinical outcomes deserves further evaluation.

SU-C-17A-05: Quantification of Intra-Fraction Motion of Breast Tumors Using Cine-MRI

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heijst, T van; Philippens, M; Bongard, D van den

2014-06-01

Purpose: Magnetic resonance imaging (MRI) enables direct characterization of intra-fraction motion ofbreast tumors, due to high softtissue contrast and geometric accuracy. The purpose is to analyzethis motion in early-stage breast-cancer patients using pre-operative supine cine-MRI. Methods: MRI was performed in 12 female early-stage breast-cancer patients on a 1.5-T Ingenia (Philips)wide-bore scanner in supine radiotherapy (RT) position, prior to breast-conserving surgery. Twotwodimensional (2D) T2-weighted balanced fast-field echo (cine-MRI) sequences were added tothe RT protocol, oriented through the tumor. They were alternately acquired in the transverse andsagittal planes, every 0.3 s during 1 min. A radiation oncologist delineated gross target volumes(GTVs) onmore » 3D contrast-enhanced MRI. Clinical target volumes (CTV = GTV + 15 mm isotropic)were generated and transferred onto the fifth time-slice of the time-series, to which subsequents lices were registered using a non-rigid Bspline algorithm; delineations were transformed accordingly. To evaluate intra-fraction CTV motion, deformation fields between the transformed delineations were derived to acquire the distance ensuring 95% surface coverage during scanning(P95%), for all in-plane directions: anteriorposterior (AP), left-right (LR), and caudal-cranial(CC). Information on LR was derived from transverse scans, CC from sagittal scans, AP fromboth sets. Results: Time-series with registration errors - induced by motion artifacts - were excluded by visual inspection. For our analysis, 11 transverse, and 8 sagittal time-series were taken into account. Themedian P95% calculated in AP (19 series), CC (8), and LR (11) was 1.8 mm (range: 0.9–4.8), 1.7mm (0.8–3.6), and 1.0 mm (0.6–3.5), respectively. Conclusion: Intra-fraction motion analysis of breast tumors was achieved using cine-MRI. These first results show that in supine RT position, motion amplitudes are limited. This information can be used for adaptive RT planning, and to develop preoperative partial-breast RT strategies, such asablative RT for early-stage breast-cancer patients.« less

Trends in Transforming Scholarly Communication and Their Implications.

ERIC Educational Resources Information Center

Liu, Ziming

2003-01-01

Explores trends in transforming scholarly publishing and possible implications for electronic publishing and digital libraries. Topics include changes in collaborative research; changes in volume of information production; and age of cited documents and how older documents are used in today's network environment. (Author/LRW)

Precipitation and Phase Transformations in 2101 Lean Duplex Stainless Steel During Isothermal Aging

NASA Astrophysics Data System (ADS)

Maetz, Jean-Yves; Cazottes, Sophie; Verdu, Catherine; Kleber, Xavier

2016-01-01

The effect of isothermal aging at 963 K (690 °C) on the microstructure of a 2101 lean duplex stainless steel, with the composition Fe-21.5Cr-5Mn-1.6Ni-0.22N-0.3Mo, was investigated using a multi-technique and multi-scale approach. The kinetics of phase transformation and precipitation was followed from a few minutes to thousands of hours using thermoelectric power measurements; based on these results, certain aging states were selected for electron microscopy characterization. Scanning electron microscopy, electron back-scattered diffraction, and transmission electron microscopy were used to quantitatively describe the microstructural evolution through crystallographic analysis, chemical analysis, and volume fraction measurements from the macroscopic scale down to the nanometric scale. During aging, the precipitation of M23C6 carbides, Cr2N nitrides, and σ phase as well as the transformation of ferrite into austenite and austenite into martensite was observed. These complex microstructural changes are controlled by Cr volume diffusion. The precipitation and phase transformation mechanisms are described.

Target oriented dimensionality reduction of hyperspectral data by Kernel Fukunaga-Koontz Transform

NASA Astrophysics Data System (ADS)

Binol, Hamidullah; Ochilov, Shuhrat; Alam, Mohammad S.; Bal, Abdullah

2017-02-01

Principal component analysis (PCA) is a popular technique in remote sensing for dimensionality reduction. While PCA is suitable for data compression, it is not necessarily an optimal technique for feature extraction, particularly when the features are exploited in supervised learning applications (Cheriyadat and Bruce, 2003) [1]. Preserving features belonging to the target is very crucial to the performance of target detection/recognition techniques. Fukunaga-Koontz Transform (FKT) based supervised band reduction technique can be used to provide this requirement. FKT achieves feature selection by transforming into a new space in where feature classes have complimentary eigenvectors. Analysis of these eigenvectors under two classes, target and background clutter, can be utilized for target oriented band reduction since each basis functions best represent target class while carrying least information of the background class. By selecting few eigenvectors which are the most relevant to the target class, dimension of hyperspectral data can be reduced and thus, it presents significant advantages for near real time target detection applications. The nonlinear properties of the data can be extracted by kernel approach which provides better target features. Thus, we propose constructing kernel FKT (KFKT) to present target oriented band reduction. The performance of the proposed KFKT based target oriented dimensionality reduction algorithm has been tested employing two real-world hyperspectral data and results have been reported consequently.

3D-segmentation of the 18F-choline PET signal for target volume definition in radiation therapy of the prostate.

PubMed

Ciernik, I Frank; Brown, Derek W; Schmid, Daniel; Hany, Thomas; Egli, Peter; Davis, J Bernard

2007-02-01

Volumetric assessment of PET signals becomes increasingly relevant for radiotherapy (RT) planning. Here, we investigate the utility of 18F-choline PET signals to serve as a structure for semi-automatic segmentation for forward treatment planning of prostate cancer. 18F-choline PET and CT scans of ten patients with histologically proven prostate cancer without extracapsular growth were acquired using a combined PET/CT scanner. Target volumes were manually delineated on CT images using standard software. Volumes were also obtained from 18F-choline PET images using an asymmetrical segmentation algorithm. PTVs were derived from CT 18F-choline PET based clinical target volumes (CTVs) by automatic expansion and comparative planning was performed. As a read-out for dose given to non-target structures, dose to the rectal wall was assessed. Planning target volumes (PTVs) derived from CT and 18F-choline PET yielded comparable results. Optimal matching of CT and 18F-choline PET derived volumes in the lateral and cranial-caudal directions was obtained using a background-subtracted signal thresholds of 23.0+/-2.6%. In antero-posterior direction, where adaptation compensating for rectal signal overflow was required, optimal matching was achieved with a threshold of 49.5+/-4.6%. 3D-conformal planning with CT or 18F-choline PET resulted in comparable doses to the rectal wall. Choline PET signals of the prostate provide adequate spatial information amendable to standardized asymmetrical region growing algorithms for PET-based target volume definition for external beam RT.

A comparison of two dose calculation algorithms-anisotropic analytical algorithm and Acuros XB-for radiation therapy planning of canine intranasal tumors.

PubMed

Nagata, Koichi; Pethel, Timothy D

2017-07-01

Although anisotropic analytical algorithm (AAA) and Acuros XB (AXB) are both radiation dose calculation algorithms that take into account the heterogeneity within the radiation field, Acuros XB is inherently more accurate. The purpose of this retrospective method comparison study was to compare them and evaluate the dose discrepancy within the planning target volume (PTV). Radiation therapy (RT) plans of 11 dogs with intranasal tumors treated by radiation therapy at the University of Georgia were evaluated. All dogs were planned for intensity-modulated radiation therapy using nine coplanar X-ray beams that were equally spaced, then dose calculated with anisotropic analytical algorithm. The same plan with the same monitor units was then recalculated using Acuros XB for comparisons. Each dog's planning target volume was separated into air, bone, and tissue and evaluated. The mean dose to the planning target volume estimated by Acuros XB was 1.3% lower. It was 1.4% higher for air, 3.7% lower for bone, and 0.9% lower for tissue. The volume of planning target volume covered by the prescribed dose decreased by 21% when Acuros XB was used due to increased dose heterogeneity within the planning target volume. Anisotropic analytical algorithm relatively underestimates the dose heterogeneity and relatively overestimates the dose to the bone and tissue within the planning target volume for the radiation therapy planning of canine intranasal tumors. This can be clinically significant especially if the tumor cells are present within the bone, because it may result in relative underdosing of the tumor. © 2017 American College of Veterinary Radiology.

Probing chemical transformation in picolitre volume aerosol droplets

NASA Astrophysics Data System (ADS)

Miloserdov, Anatolij; Day, Calum P. F.; Rosario, Gabriela L.; Horrocks, Benjamin R.; Carruthers, Antonia E.

2017-08-01

We have demonstrated chemical transformation in single microscopic-sized aerosol droplets localised in optical tweezers. Droplets in situ are measured during chemical transformation processes of solvent exchange and solute transformation through an ion exchange reaction. Solvent exchange between deionised water and heavy water in aerosol droplets is monitored through observation of the OH and OD Raman stretches. A change in solute chemistry of aerosol is achieved through droplet coalescence events between calcium chloride and sodium carbonate to promote ion exchange. The transformation forming meta-stable and stable states of CaCO3 is observed and analysed using Gaussian peak decomposition to reveal polymorphs.

Investigating different computed tomography techniques for internal target volume definition.

PubMed

Yoganathan, S A; Maria Das, K J; Subramanian, V Siva; Raj, D Gowtham; Agarwal, Arpita; Kumar, Shaleen

2017-01-01

The aim of this work was to evaluate the various computed tomography (CT) techniques such as fast CT, slow CT, breath-hold (BH) CT, full-fan cone beam CT (FF-CBCT), half-fan CBCT (HF-CBCT), and average CT for delineation of internal target volume (ITV). In addition, these ITVs were compared against four-dimensional CT (4DCT) ITVs. Three-dimensional target motion was simulated using dynamic thorax phantom with target insert of diameter 3 cm for ten respiration data. CT images were acquired using a commercially available multislice CT scanner, and the CBCT images were acquired using On-Board-Imager. Average CT was generated by averaging 10 phases of 4DCT. ITVs were delineated for each CT by contouring the volume of the target ball; 4DCT ITVs were generated by merging all 10 phases target volumes. Incase of BH-CT, ITV was derived by boolean of CT phases 0%, 50%, and fast CT target volumes. ITVs determined by all CT and CBCT scans were significantly smaller (P < 0.05) than the 4DCT ITV, whereas there was no significant difference between average CT and 4DCT ITVs (P = 0.17). Fast CT had the maximum deviation (-46.1% ± 20.9%) followed by slow CT (-34.3% ± 11.0%) and FF-CBCT scans (-26.3% ± 8.7%). However, HF-CBCT scans (-12.9% ± 4.4%) and BH-CT scans (-11.1% ± 8.5%) resulted in almost similar deviation. On the contrary, average CT had the least deviation (-4.7% ± 9.8%). When comparing with 4DCT, all the CT techniques underestimated ITV. In the absence of 4DCT, the HF-CBCT target volumes with appropriate margin may be a reasonable approach for defining the ITV.

The Investigation of Strain-Induced Martensite Reverse Transformation in AISI 304 Austenitic Stainless Steel

NASA Astrophysics Data System (ADS)

Cios, G.; Tokarski, T.; Żywczak, A.; Dziurka, R.; Stępień, M.; Gondek, Ł.; Marciszko, M.; Pawłowski, B.; Wieczerzak, K.; Bała, P.

2017-10-01

This paper presents a comprehensive study on the strain-induced martensitic transformation and reversion transformation of the strain-induced martensite in AISI 304 stainless steel using a number of complementary techniques such as dilatometry, calorimetry, magnetometry, and in-situ X-ray diffraction, coupled with high-resolution microstructural transmission Kikuchi diffraction analysis. Tensile deformation was applied at temperatures between room temperature and 213 K (-60 °C) in order to obtain a different volume fraction of strain-induced martensite (up to 70 pct). The volume fraction of the strain-induced martensite, measured by the magnetometric method, was correlated with the total elongation, hardness, and linear thermal expansion coefficient. The thermal expansion coefficient, as well as the hardness of the strain-induced martensitic phase was evaluated. The in-situ thermal treatment experiments showed unusual changes in the kinetics of the reverse transformation (α' → γ). The X-ray diffraction analysis revealed that the reverse transformation may be stress assisted—strains inherited from the martensitic transformation may increase its kinetics at the lower annealing temperature range. More importantly, the transmission Kikuchi diffraction measurements showed that the reverse transformation of the strain-induced martensite proceeds through a displacive, diffusionless mechanism, maintaining the Kurdjumov-Sachs crystallographic relationship between the martensite and the reverted austenite. This finding is in contradiction to the results reported by other researchers for a similar alloy composition.

The Comparison Study of Quadratic Infinite Beam Program on Optimization Instensity Modulated Radiation Therapy Treatment Planning (IMRTP) between Threshold and Exponential Scatter Method with CERR® In The Case of Lung Cancer

NASA Astrophysics Data System (ADS)

Hardiyanti, Y.; Haekal, M.; Waris, A.; Haryanto, F.

2016-08-01

This research compares the quadratic optimization program on Intensity Modulated Radiation Therapy Treatment Planning (IMRTP) with the Computational Environment for Radiotherapy Research (CERR) software. We assumed that the number of beams used for the treatment planner was about 9 and 13 beams. The case used the energy of 6 MV with Source Skin Distance (SSD) of 100 cm from target volume. Dose calculation used Quadratic Infinite beam (QIB) from CERR. CERR was used in the comparison study between Gauss Primary threshold method and Gauss Primary exponential method. In the case of lung cancer, the threshold variation of 0.01, and 0.004 was used. The output of the dose was distributed using an analysis in the form of DVH from CERR. The maximum dose distributions obtained were on the target volume (PTV) Planning Target Volume, (CTV) Clinical Target Volume, (GTV) Gross Tumor Volume, liver, and skin. It was obtained that if the dose calculation method used exponential and the number of beam 9. When the dose calculation method used the threshold and the number of beam 13, the maximum dose distributions obtained were on the target volume PTV, GTV, heart, and skin.

SU-F-T-611: Critical Analysis and Efficacy of Linac Based (Beam Modulator) and Cyberknife Treatment Plans for Acoustic Neuroma/schwannoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

KP, Karrthick; Kataria, T; Thiyagarajan, R

Purpose: To study the critical analysis and efficacy of Linac and Cyberknife (CK) treatment plans for acoustic neuroma/schwannoma. Methods: Twelve of acoustic neuroma/schwannoma patients were taken for these study that. Treatment plans were generated in Multiplan treatment planning system (TPS) for CK using 5,7.5 and 10mm diameter collimators. Target volumes were in the range of 0.280 cc to 9.256 cc. Prescription dose (Rx) ranges from 1150cGy to 1950cGy delivered over 1 to 3 Fractions. For same patients stereotactic Volumetric modulated arc plans were generated using Elekta Linac with MLC thickness of 4mm in Monaco TPS. Appropriate calculation algorithms and gridmore » size were used with same Rx and organ at risk (OAR) constrains for both Linac and CK plans. Treatment plans were developed to achieve at least 95% of the target volume to receive the Rx. The dosimetric indices such as conformity index (CI), coverage, OAR dose and volume receiving 50% of Rx (V50%) were used to evaluate the plans. Results: Target volumes ranges from 0.280 cc to 3.5cc shows the CI of 1.16±0.109 and 1.53±0.360 for cyberknife and Linac plans respectively. For small volume targets, the OARs were well spared in CK plans. There are no significant differences in CI and OAR doses were observed between CK and Linac plans that have the target volume >3.5 cc. Perhaps the V50% were lesser in CK plans, and found to be 12.8± 8.4 and 22.8 ± 15.0 for CK and Linac respectively. Conclusion: The analysis shows the importance of collimator size for small volume targets. The target volumes >3.5 cc can be treated in Linac as comparable with CK. For targets <3.5cc CK plans showed superior plan quality with better CI and OAR sparing than the Linac based plans. Further studies may require evaluating the clinical advantage of CK robotic system.« less

SU-G-TeP2-08: Evaluation of Plastic Scintillator Detector for Small Field Stereotactic Patient-Specific Quality Assurance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Qin, Y; Gardner, S; Huang, Y

Purpose: To evaluate the performance of a commercial plastic scintillator detector (PSD) for small-field stereotactic patient-specific quality assurance using flattening-filter-free (FFF) beams. Methods: A total of ten spherical targets (volume range:[0.03cc–2cc]) were planned using Dynamic Conformal Arc(DCA-10 plans) and Volumetric Modulated Arc Therapy(VMAT-10 plans) techniques in Eclipse(AAA v.11, 1mm dose calculation grid size). Additionally, 15 previously-treated cranial and spine SRS plans were evaluated (6 DCA, 9 VMAT, volume range:[0.04cc–119.02cc]). All measurements were acquired using Varian Edge equipped with HDMLC. Three detectors were used: PinPoint ion chamber (PTW;active volume 0.015cc), Exradin W1 PSD (Standard Imaging;active volume 0.002cc), and Gafchromic EBT3 filmmore » (Ashland). PinPoint and PSD were positioned perpendicular to beam axis in a Lucy phantom (Standard Imaging). Films were placed at isocenter in solid water. Calibration films were delivered for absolute dose analysis. Results: For large spherical targets(>1.5cc) with DCA, all detectors agreed within 1% of AAA calculations. As target volume decreased, PSD measured higher doses than AAA (maximum difference: 3.3% at 0.03cc target), while PinPoint chamber measured lower doses (maximum difference:-3.8% at 0.03cc target). Inter-detector differences between pinpoint and PSD increased with decreasing target size; differences>5% were observed for targets<0.09cc. Similar trends for inter-detector behavior were observed for clinical plans. For target sizes<0.08cc, PSD measured>5% higher dose than PinPoint chamber (maximum difference: 9.25% at 0.04cc target). Film demonstrated agreement of −0.19±1.47% with PSD for all spherical targets, and agreement within −0.98±2.25% for all 15 clinical targets. Unlike DCA, VMAT plans did not show improved AAA-to-detector agreements for large targets. Conclusion: For all targets, the PSD measurements agreed with film within 1.0%, on average. For small volume targets (<0.10cc), PSD agreed with film but measured significantly higher doses (>5%) compared with the pin point ion chamber. The plastic scintillator detector appears to be suitable for accurate measurements of small SRS targets.« less

Use of biotin targeted methotrexate–human serum albumin conjugated nanoparticles to enhance methotrexate antitumor efficacy

PubMed Central

Taheri, Azade; Dinarvand, Rassoul; Nouri, Faranak Salman; Khorramizadeh, Mohammad Reza; Borougeni, Atefeh Taheri; Mansoori, Pooria; Atyabi, Fatemeh

2011-01-01

Biotin molecules could be used as suitable targeting moieties in targeted drug delivery systems against tumors. To develop a biotin targeted drug delivery system, we employed human serum albumin (HSA) as a carrier. Methotrexate (MTX) molecules were conjugated to HSA. MTX-HSA nanoparticles (MTX-HSA NPs) were prepared from these conjugates by cross-linking the HSA molecules. Biotin molecules were then conjugated on the surface of MTX-HSA NPs. The anticancer efficacy of biotin targeted MTX-HSA NPs was evaluated in mice bearing 4T1 breast carcinoma. A single dose of biotin targeted MTX-HSA NPs showed stronger in vivo antitumor activity than non-targeted MTX-HSA NPs and free MTX. By 7 days after treatment, average tumor volume in the biotin targeted MTX-HSA NPs-treated group decreased to 17.6% of the initial tumor volume when the number of attached biotin molecules on MTX-HSA-NPs was the highest. Average tumor volume in non-targeted MTX-HSA NPs-treated mice grew rapidly and reached 250.7% of the initial tumor volume. Biotin targeted MTX-HSA NPs increased the survival of tumor-bearing mice to 47.5 ± 0.71 days and increased their life span up to 216.7%. Mice treated with biotin targeted MTX-HSA NPs showed slight body weight loss (8%) 21 days after treatment, whereas non-targeted MTX-HSA NPs treatment at the same dose caused a body weight loss of 27.05% ± 3.1%. PMID:21931482

4D computed tomography scans for conformal thoracic treatment planning: is a single scan sufficient to capture thoracic tumor motion?

NASA Astrophysics Data System (ADS)

Tseng, Yolanda D.; Wootton, Landon; Nyflot, Matthew; Apisarnthanarax, Smith; Rengan, Ramesh; Bloch, Charles; Sandison, George; St. James, Sara

2018-01-01

Four dimensional computed tomography (4DCT) scans are routinely used in radiation therapy to determine the internal treatment volume for targets that are moving (e.g. lung tumors). The use of these studies has allowed clinicians to create target volumes based upon the motion of the tumor during the imaging study. The purpose of this work is to determine if a target volume based on a single 4DCT scan at simulation is sufficient to capture thoracic motion. Phantom studies were performed to determine expected differences between volumes contoured on 4DCT scans and those on the evaluation CT scans (slow scans). Evaluation CT scans acquired during treatment of 11 patients were compared to the 4DCT scans used for treatment planning. The images were assessed to determine if the target remained within the target volume determined during the first 4DCT scan. A total of 55 slow scans were compared to the 11 planning 4DCT scans. Small differences were observed in phantom between the 4DCT volumes and the slow scan volumes, with a maximum of 2.9%, that can be attributed to minor differences in contouring and the ability of the 4DCT scan to adequately capture motion at the apex and base of the motion trajectory. Larger differences were observed in the patients studied, up to a maximum volume difference of 33.4%. These results demonstrate that a single 4DCT scan is not adequate to capture all thoracic motion throughout treatment.

Event-Related Potential Responses to Task Switching Are Sensitive to Choice of Spatial Filter

PubMed Central

Wong, Aaron S. W.; Cooper, Patrick S.; Conley, Alexander C.; McKewen, Montana; Fulham, W. Ross; Michie, Patricia T.; Karayanidis, Frini

2018-01-01

Event-related potential (ERP) studies using the task-switching paradigm show that multiple ERP components are modulated by activation of proactive control processes involved in preparing to repeat or switch task and reactive control processes involved in implementation of the current or new task. Our understanding of the functional significance of these ERP components has been hampered by variability in their robustness, as well as their temporal and scalp distribution across studies. The aim of this study is to examine the effect of choice of reference electrode or spatial filter on the number, timing and scalp distribution of ERP elicited during task-switching. We compared four configurations, including the two most common (i.e., average mastoid reference and common average reference) and two novel ones that aim to reduce volume conduction (i.e., reference electrode standardization technique (REST) and surface Laplacian) on mixing cost and switch cost effects in cue-locked and target-locked ERP waveforms in 201 healthy participants. All four spatial filters showed the same well-characterized ERP components that are typically seen in task-switching paradigms: the cue-locked switch positivity and target-locked N2/P3 effect. However, both the number of ERP effects associated with mixing and switch cost, and their temporal and spatial resolution were greater with the surface Laplacian transformation which revealed rapid temporal adjustments that were not identifiable with other spatial filters. We conclude that the surface Laplacian transformation may be more suited to characterize EEG signatures of complex spatiotemporal networks involved in cognitive control. PMID:29568260

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tan, Y.B.; Yang, L.H.; Duan, J.L.

The kinetics of the β → α phase transformation in the 47Zr–45Ti–5Al–3V (wt.%) alloy with different initial β grain sizes under isothermal conditions was investigated by X-ray diffraction. The results showed that the volume fraction of α phase first increased with increasing aging time, and then reached an equilibrium value. The equilibrium value of α phase decreased with increased aging temperature. At the same aging temperature and time, the volume fraction of α phase in the 47Zr–45Ti–5Al–3V alloy solution-treated at 850 °C was higher than at 1050 °C, and the size of α phase in the 47Zr–45Ti–5Al–3V alloy solution-treated atmore » 850 °C was larger than that at 1050 °C. The kinetics of the β → α phase transformation was modeled under isothermal conditions in the theoretical frame of the Johnson–Mehl–Avrami–Kolmogorov (JMAK) theory. The Avrami index (n) increased with increasing aging temperature, while the reaction rate constant (k) decreased. - Highlights: • The kinetics of the β → α phase transformation in the ZrTiAlV alloy was investigated. • The volume fraction of α phase first increased and then reached an equilibrium value. • The kinetics of the β → α phase transformation was modeled by the JMAK theory. • The n increased with increasing aging temperature, while the k decreased.« less

Fast-match on particle swarm optimization with variant system mechanism

NASA Astrophysics Data System (ADS)

Wang, Yuehuang; Fang, Xin; Chen, Jie

2018-03-01

Fast-Match is a fast and effective algorithm for approximate template matching under 2D affine transformations, which can match the target with maximum similarity without knowing the target gesture. It depends on the minimum Sum-of-Absolute-Differences (SAD) error to obtain the best affine transformation. The algorithm is widely used in the field of matching images because of its fastness and robustness. In this paper, our approach is to search an approximate affine transformation over Particle Swarm Optimization (PSO) algorithm. We treat each potential transformation as a particle that possesses memory function. Each particle is given a random speed and flows throughout the 2D affine transformation space. To accelerate the algorithm and improve the abilities of seeking the global excellent result, we have introduced the variant system mechanism on this basis. The benefit is that we can avoid matching with huge amount of potential transformations and falling into local optimal condition, so that we can use a few transformations to approximate the optimal solution. The experimental results prove that our method has a faster speed and a higher accuracy performance with smaller affine transformation space.

Spectral Target Detection using Schroedinger Eigenmaps

NASA Astrophysics Data System (ADS)

Dorado-Munoz, Leidy P.

Applications of optical remote sensing processes include environmental monitoring, military monitoring, meteorology, mapping, surveillance, etc. Many of these tasks include the detection of specific objects or materials, usually few or small, which are surrounded by other materials that clutter the scene and hide the relevant information. This target detection process has been boosted lately by the use of hyperspectral imagery (HSI) since its high spectral dimension provides more detailed spectral information that is desirable in data exploitation. Typical spectral target detectors rely on statistical or geometric models to characterize the spectral variability of the data. However, in many cases these parametric models do not fit well HSI data that impacts the detection performance. On the other hand, non-linear transformation methods, mainly based on manifold learning algorithms, have shown a potential use in HSI transformation, dimensionality reduction and classification. In target detection, non-linear transformation algorithms are used as preprocessing techniques that transform the data to a more suitable lower dimensional space, where the statistical or geometric detectors are applied. One of these non-linear manifold methods is the Schroedinger Eigenmaps (SE) algorithm that has been introduced as a technique for semi-supervised classification. The core tool of the SE algorithm is the Schroedinger operator that includes a potential term that encodes prior information about the materials present in a scene, and enables the embedding to be steered in some convenient directions in order to cluster similar pixels together. A completely novel target detection methodology based on SE algorithm is proposed for the first time in this thesis. The proposed methodology does not just include the transformation of the data to a lower dimensional space but also includes the definition of a detector that capitalizes on the theory behind SE. The fact that target pixels and those similar pixels are clustered in a predictable region of the low-dimensional representation is used to define a decision rule that allows one to identify target pixels over the rest of pixels in a given image. In addition, a knowledge propagation scheme is used to combine spectral and spatial information as a means to propagate the "potential constraints" to nearby points. The propagation scheme is introduced to reinforce weak connections and improve the separability between most of the target pixels and the background. Experiments using different HSI data sets are carried out in order to test the proposed methodology. The assessment is performed from a quantitative and qualitative point of view, and by comparing the SE-based methodology against two other detection methodologies that use linear/non-linear algorithms as transformations and the well-known Adaptive Coherence/Cosine Estimator (ACE) detector. Overall results show that the SE-based detector outperforms the other two detection methodologies, which indicates the usefulness of the SE transformation in spectral target detection problems.

Phosphoproteins in extracellular vesicles as candidate markers for breast cancer

PubMed Central

Chen, I-Hsuan; Xue, Liang; Hsu, Chuan-Chih; Paez, Juan Sebastian Paez; Pan, Li; Andaluz, Hillary; Wendt, Michael K.; Iliuk, Anton B.; Tao, W. Andy

2017-01-01

The state of protein phosphorylation can be a key determinant of cellular physiology such as early-stage cancer, but the development of phosphoproteins in biofluids for disease diagnosis remains elusive. Here we demonstrate a strategy to isolate and identify phosphoproteins in extracellular vesicles (EVs) from human plasma as potential markers to differentiate disease from healthy states. We identified close to 10,000 unique phosphopeptides in EVs isolated from small volumes of plasma samples. Using label-free quantitative phosphoproteomics, we identified 144 phosphoproteins in plasma EVs that are significantly higher in patients diagnosed with breast cancer compared with healthy controls. Several biomarkers were validated in individual patients using paralleled reaction monitoring for targeted quantitation. This study demonstrates that the development of phosphoproteins in plasma EV as disease biomarkers is highly feasible and may transform cancer screening and monitoring. PMID:28270605

Phosphoproteins in extracellular vesicles as candidate markers for breast cancer.

PubMed

Chen, I-Hsuan; Xue, Liang; Hsu, Chuan-Chih; Paez, Juan Sebastian Paez; Pan, Li; Andaluz, Hillary; Wendt, Michael K; Iliuk, Anton B; Zhu, Jian-Kang; Tao, W Andy

2017-03-21

The state of protein phosphorylation can be a key determinant of cellular physiology such as early-stage cancer, but the development of phosphoproteins in biofluids for disease diagnosis remains elusive. Here we demonstrate a strategy to isolate and identify phosphoproteins in extracellular vesicles (EVs) from human plasma as potential markers to differentiate disease from healthy states. We identified close to 10,000 unique phosphopeptides in EVs isolated from small volumes of plasma samples. Using label-free quantitative phosphoproteomics, we identified 144 phosphoproteins in plasma EVs that are significantly higher in patients diagnosed with breast cancer compared with healthy controls. Several biomarkers were validated in individual patients using paralleled reaction monitoring for targeted quantitation. This study demonstrates that the development of phosphoproteins in plasma EV as disease biomarkers is highly feasible and may transform cancer screening and monitoring.

Transforming America: Cultural Cohesion, Educational Achievement, and Global Competitiveness. Educational Psychology. Volume 7

ERIC Educational Resources Information Center

DeVillar, Robert A.; Jiang, Binbin

2011-01-01

Creatively and rigorously blending historical research and contemporary data from various disciplines, this book cogently and comprehensively illustrates the problems and opportunities the American nation faces in education, economics, and the global arena. The authors propose a framework of transformation that would render American culture no…

Readings in Applied Transformational Grammar.

ERIC Educational Resources Information Center

Lester, Mark, Ed.

This volume contains nineteen essays, dealing with various aspects of transformational grammar, by scholars such as Noam Chomsky, Eric H. Lenneberg, and Leon Jakobovits. These essays have been reprinted from sources such as "College English" and "Language Learning" and are intended for the most part for a nontechnical audience. The anthology is…

Extracting Micro-Doppler Radar Signatures from Rotating Targets Using Fourier-Bessel Transform and Time-Frequency Analysis

DTIC Science & Technology

2014-10-16

Time-Frequency analysis, Short-Time Fourier Transform, Wigner Ville Distribution, Fourier Bessel Transform, Fractional Fourier Transform. I...INTRODUCTION Most widely used time-frequency transforms are short-time Fourier Transform (STFT) and Wigner Ville distribution (WVD). In STFT, time and...frequency resolutions are limited by the size of window function used in calculating STFT. For mono-component signals, WVD gives the best time and frequency

DNA transformation via local heat shock

NASA Astrophysics Data System (ADS)

Li, Sha; Meadow Anderson, L.; Yang, Jui-Ming; Lin, Liwei; Yang, Haw

2007-07-01

This work describes transformation of foreign DNA into bacterial host cells by local heat shock using a microfluidic system with on-chip, built-in platinum heaters. Plasmid DNA encoding ampicillin resistance and a fluorescent protein can be effectively transformed into the DH5α chemically competent E. coli using this device. Results further demonstrate that only one-thousandth of volume is required to obtain transformation efficiencies as good as or better than conventional practices. As such, this work complements other lab-on-a-chip technologies for potential gene cloning/therapy and protein expression applications.

Heat storage in alloy transformations

NASA Technical Reports Server (NTRS)

Birchenall, C. E.; Gueceri, S. I.

1980-01-01

The theory of eutectic transformation was examined to find guidelines to the best material combinations to examine. The heats of transformation were measured calorimetrically, and the volume changes of expanding solid mixtures and homogeneous liquid solutions, especially during the transformation between the two states at fixed temperature, were measured by changes in X-ray absorption. Heat flow models appropriate to storage in phase change materials were developed along with efficient calculating procedures so that the relative importance of the problems associated with energy storage density, heat conduction, and similar properties could be assessed.

Impact of Node Negative Target Volume Delineation on Contralateral Parotid Gland Dose Sparing Using IMRT in Head and Neck Cancer.

PubMed

Magnuson, William J; Urban, Erich; Bayliss, R Adam; Harari, Paul M

2015-06-01

There is considerable practice variation in treatment of the node negative (N0) contralateral neck in patients with head and neck cancer. In this study, we examined the impact of N0 neck target delineation volume on radiation dose to the contralateral parotid gland. Following institutional review board approval, 12 patients with head and neck cancer were studied. All had indications for treatment of the N0 neck, such as midline base of tongue or soft palate extension or advanced ipsilateral nodal disease. The N0 neck volumes were created using the Radiation Therapy Oncology Group head and neck contouring atlas. The physician-drawn N0 neck clinical target volume (CTV) was expanded by 25% to 200% to generate volume variation, followed by a 3-mm planning target volume (PTV) expansion. Surrounding organs at risk were contoured and complete intensity-modulated radiation therapy plans were generated for each N0 volume expansion. The median N0 target volume drawn by the radiation oncologist measured 93 cm(3) (range 71-145). Volumetric expansion of the N0 CTV by 25% to 200% increased the resultant mean dose to the contralateral parotid gland by 1.4 to 8.5 Gray (Gy). For example, a 4.1-mm increase in the N0 neck CTV translated to a 2.0-Gy dose increase to the parotid, 7.4 mm to a 4.5 Gy dose increase, and 12.5 mm to an 8.5 Gy dose increase, respectively. The treatment volume designated for the N0 neck has profound impact on resultant dose to the contralateral parotid gland. Variations of up to 15 mm are routine across physicians in target contouring, reflecting individual preference and training expertise. Depending on the availability of immobilization and image guidance techniques, experts commonly recommend 3 to 10 mm margin expansions to generate the PTV. Careful attention to the original volume of the N0 neck CTV, as well as expansion margins, is important in achieving effective contralateral gland sparing to reduce the resultant xerostomia and dysguesia that may ensue after radiotherapy. © The Author(s) 2014.

Use of volume-targeted non-invasive bilevel positive airway pressure ventilation in a patient with amyotrophic lateral sclerosis*,**

PubMed Central

Diaz-Abad, Montserrat; Brown, John Edward

2014-01-01

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease in which most patients die of respiratory failure. Although volume-targeted non-invasive bilevel positive airway pressure (BPAP) ventilation has been studied in patients with chronic respiratory failure of various etiologies, its use in ALS has not been reported. We present the case of a 66-year-old woman with ALS and respiratory failure treated with volume-targeted BPAP ventilation for 15 weeks. Weekly data downloads showed that disease progression was associated with increased respiratory muscle weakness, decreased spontaneous breathing, and increased use of non-invasive positive pressure ventilation, whereas tidal volume and minute ventilation remained relatively constant. PMID:25210968

Nanoindentation study on the characteristic of shear transformation zone in a Pd-based bulk metallic glass during serrated flow

NASA Astrophysics Data System (ADS)

Liao, G. K.; Long, Z. L.; Zhao, M. S. Z.; Peng, L.; Chai, W.; Ping, Z. H.

2018-04-01

This paper presents the research on the evolution of shear transformation zone (STZ) in a Pd-based bulk metallic glass (BMG) during serrated flow under nanoindentation. A novel method of estimating the STZ volume through statistical analysis of the serrated flow behavior was proposed for the first time. Based on the proposed method, the STZ volume of the studied BMG at various peak loads have been systematically investigated. The results indicate that the measured STZ volumes are in good agreement with that documented in literature, and the STZ size exhibits an increasing trend during indentation. Moreover, the correlation between the serrated flow dynamics and the STZ activation has also been evaluated. It is found that the STZ activation can promote the formation of self-organized critical (SOC) state during serrated flow.

Exact solution for heat transfer free convection flow of Maxwell nanofluids with graphene nanoparticles

NASA Astrophysics Data System (ADS)

Aman, Sidra; Zuki Salleh, Mohd; Ismail, Zulkhibri; Khan, Ilyas

2017-09-01

This article focuses on the flow of Maxwell nanofluids with graphene nanoparticles over a vertical plate (static) with constant wall temperature. Possessing high thermal conductivity, engine oil is useful to be chosen as base fluid with free convection. The problem is modelled in terms of PDE’s with boundary conditions. Some suitable non-dimensional variables are interposed to transform the governing equations into dimensionless form. The generated equations are solved via Laplace transform technique. Exact solutions are evaluated for velocity and temperature. These solutions are significantly controlled by some parameters involved. Temperature rises with elevation in volume fraction while Velocity decreases with increment in volume fraction. A comparison with previous published results are established and discussed. Moreover, a detailed discussion is made for influence of volume fraction on the flow and heat profile.

Combining transrectal ultrasound and CT for image-guided adaptive brachytherapy of cervical cancer: Proof of concept.

PubMed

Nesvacil, Nicole; Schmid, Maximilian P; Pötter, Richard; Kronreif, Gernot; Kirisits, Christian

To investigate the feasibility of a treatment planning workflow for three-dimensional image-guided cervix cancer brachytherapy, combining volumetric transrectal ultrasound (TRUS) for target definition with CT for dose optimization to organs at risk (OARs), for settings with no access to MRI. A workflow for TRUS/CT-based volumetric treatment planning was developed, based on a customized system including ultrasound probe, stepper unit, and software for image volume acquisition. A full TRUS/CT-based workflow was simulated in a clinical case and compared with MR- or CT-only delineation. High-risk clinical target volume was delineated on TRUS, and OARs were delineated on CT. Manually defined tandem/ring applicator positions on TRUS and CT were used as a reference for rigid registration of the image volumes. Treatment plan optimization for TRUS target and CT organ volumes was performed and compared to MRI and CT target contours. TRUS/CT-based contouring, applicator reconstruction, image fusion, and treatment planning were feasible, and the full workflow could be successfully demonstrated. The TRUS/CT plan fulfilled all clinical planning aims. Dose-volume histogram evaluation of the TRUS/CT-optimized plan (high-risk clinical target volume D 90 , OARs D 2cm³ for) on different image modalities showed good agreement between dose values reported for TRUS/CT and MRI-only reference contours and large deviations for CT-only target parameters. A TRUS/CT-based workflow for full three-dimensional image-guided cervix brachytherapy treatment planning seems feasible and may be clinically comparable to MRI-based treatment planning. Further development to solve challenges with applicator definition in the TRUS volume is required before systematic applicability of this workflow. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

Laser program annual report, 1980

DOE Office of Scientific and Technical Information (OSTI.GOV)

Coleman, L.W.; Krupke, W.F.; Strack, J.R.

1981-06-01

Volume 2 contains five sections that cover the areas of target design, target fabrication, diagnostics, and fusion experiments. Section 3 reports on target design activities, plasma theory and simulation, code development, and atomic theory. Section 4 presents the accomplishments of the Target Fabrication Group, Section 5 contains the results of our diagnostics development, and Section 6 describes advances made in the management and analysis of experimental data. Finally, Section 7 in Volume 2 reports the results of laser target experiments conducted during the year.

A Progressive Black Top Hat Transformation Algorithm for Estimating Valley Volumes from DEM Data

NASA Astrophysics Data System (ADS)

Luo, W.; Pingel, T.; Heo, J.; Howard, A. D.

2013-12-01

The amount of valley incision and valley volume are important parameters in geomorphology and hydrology research, because they are related to the amount erosion (and thus the volume of sediments) and the amount of water needed to create the valley. This is not only the case for terrestrial research but also for planetary research as such figuring out how much water was on Mars. With readily available digital elevation model (DEM) data, the Black Top Hat (BTH) transformation, an image processing technique for extracting dark features on a variable background, has been applied to DEM data to extract valley depth and estimate valley volume. However, previous studies typically use one single structuring element size for extracting the valley feature and one single threshold value for removing noise, resulting in some finer features such as tributaries not being extracted and underestimation of valley volume. Inspired by similar algorithms used in LiDAR data analysis to separate above ground features and bare earth topography, here we propose a progressive BTH (PBTH) transformation algorithm, where the structuring elements size is progressively increased to extract valleys of different orders. In addition, a slope based threshold was introduced to automatically adjust the threshold values for structuring elements with different sizes. Connectivity and shape parameters of the masked regions were used to keep the long linear valleys while removing other smaller non-connected regions. Preliminary application of the PBTH to Grand Canyon and two sites on Mars has produced promising results. More testing and fine-tuning is in progress. The ultimate goal of the project is to apply the algorithm to estimate the volume of valley networks on Mars and the volume of water needed to form the valleys we observe today and thus infer the nature of the hydrologic cycle on early Mars. The project is funded by NASA's Mars Data Analysis program.

Feature Interactions Enable Decoding of Sensorimotor Transformations for Goal-Directed Movement

PubMed Central

Barany, Deborah A.; Della-Maggiore, Valeria; Viswanathan, Shivakumar; Cieslak, Matthew

2014-01-01

Neurophysiology and neuroimaging evidence shows that the brain represents multiple environmental and body-related features to compute transformations from sensory input to motor output. However, it is unclear how these features interact during goal-directed movement. To investigate this issue, we examined the representations of sensory and motor features of human hand movements within the left-hemisphere motor network. In a rapid event-related fMRI design, we measured cortical activity as participants performed right-handed movements at the wrist, with either of two postures and two amplitudes, to move a cursor to targets at different locations. Using a multivoxel analysis technique with rigorous generalization tests, we reliably distinguished representations of task-related features (primarily target location, movement direction, and posture) in multiple regions. In particular, we identified an interaction between target location and movement direction in the superior parietal lobule, which may underlie a transformation from the location of the target in space to a movement vector. In addition, we found an influence of posture on primary motor, premotor, and parietal regions. Together, these results reveal the complex interactions between different sensory and motor features that drive the computation of sensorimotor transformations. PMID:24828640

A weighted adjustment of a similarity transformation between two point sets containing errors

NASA Astrophysics Data System (ADS)

Marx, C.

2017-10-01

For an adjustment of a similarity transformation, it is often appropriate to consider that both the source and the target coordinates of the transformation are affected by errors. For the least squares adjustment of this problem, a direct solution is possible in the cases of specific-weighing schemas of the coordinates. Such a problem is considered in the present contribution and a direct solution is generally derived for the m-dimensional space. The applied weighing schema allows (fully populated) point-wise weight matrices for the source and target coordinates, both weight matrices have to be proportional to each other. Additionally, the solutions of two borderline cases of this weighting schema are derived, which only consider errors in the source or target coordinates. The investigated solution of the rotation matrix of the adjustment is independent of the scaling between the weight matrices of the source and the target coordinates. The mentioned borderline cases, therefore, have the same solution of the rotation matrix. The direct solution method is successfully tested on an example of a 3D similarity transformation using a comparison with an iterative solution based on the Gauß-Helmert model.

Biotechnology of oil palm: strategies towards manipulation of lipid content and composition.

PubMed

Parveez, Ghulam Kadir Ahmad; Rasid, Omar Abdul; Masani, Mat Yunus Abdul; Sambanthamurthi, Ravigadevi

2015-04-01

Oil palm is a major economic crop for Malaysia. The major challenges faced by the industry are labor shortage, availability of arable land and unstable commodity price. This has caused the industry to diversify its applications into higher value products besides increasing its yield. While conventional breeding has its limitations, biotechnology was identified as one of the tools for overcoming the above challenges. Research on biotechnology of oil palm began more than two decades ago leveraging a multidisciplinary approach involving biochemical studies, gene and promoter isolation, transformation vector construction and finally genetic transformation to produce the targeted products. The main target of oil palm biotechnology research is to increase oleic acid in the mesocarp. Other targets are stearic acid, palmitoleic acid, ricinoleic acid, lycopene (carotenoid) and biodegradable plastics. Significant achievements were reported for the biochemical studies, isolation of useful oil palm genes and characterization of important promoters. A large number of transformation constructs for various targeted products were successfully produced using the isolated oil palm genes and promoters. Finally transformation of these constructs into oil palm embryogenic calli was carried out while the regeneration of transgenic oil palm harboring the useful genes is in progress.

Digital staining for histopathology multispectral images by the combined application of spectral enhancement and spectral transformation.

PubMed

Bautista, Pinky A; Yagi, Yukako

2011-01-01

In this paper we introduced a digital staining method for histopathology images captured with an n-band multispectral camera. The method consisted of two major processes: enhancement of the original spectral transmittance and the transformation of the enhanced transmittance to its target spectral configuration. Enhancement is accomplished by shifting the original transmittance with the scaled difference between the original transmittance and the transmittance estimated with m dominant principal component (PC) vectors;the m-PC vectors were determined from the transmittance samples of the background image. Transformation of the enhanced transmittance to the target spectral configuration was done using an nxn transformation matrix, which was derived by applying a least square method to the enhanced and target spectral training data samples of the different tissue components. Experimental results on the digital conversion of a hematoxylin and eosin (H&E) stained multispectral image to its Masson's trichrome stained (MT) equivalent shows the viability of the method.

An improved KCF tracking algorithm based on multi-feature and multi-scale

NASA Astrophysics Data System (ADS)

Wu, Wei; Wang, Ding; Luo, Xin; Su, Yang; Tian, Weiye

2018-02-01

The purpose of visual tracking is to associate the target object in a continuous video frame. In recent years, the method based on the kernel correlation filter has become the research hotspot. However, the algorithm still has some problems such as video capture equipment fast jitter, tracking scale transformation. In order to improve the ability of scale transformation and feature description, this paper has carried an innovative algorithm based on the multi feature fusion and multi-scale transform. The experimental results show that our method solves the problem that the target model update when is blocked or its scale transforms. The accuracy of the evaluation (OPE) is 77.0%, 75.4% and the success rate is 69.7%, 66.4% on the VOT and OTB datasets. Compared with the optimal one of the existing target-based tracking algorithms, the accuracy of the algorithm is improved by 6.7% and 6.3% respectively. The success rates are improved by 13.7% and 14.2% respectively.

Supervised target detection in hyperspectral images using one-class Fukunaga-Koontz Transform

NASA Astrophysics Data System (ADS)

Binol, Hamidullah; Bal, Abdullah

2016-05-01

A novel hyperspectral target detection technique based on Fukunaga-Koontz transform (FKT) is presented. FKT offers significant properties for feature selection and ordering. However, it can only be used to solve multi-pattern classification problems. Target detection may be considered as a two-class classification problem, i.e., target versus background clutter. Nevertheless, background clutter typically contains different types of materials. That's why; target detection techniques are different than classification methods by way of modeling clutter. To avoid the modeling of the background clutter, we have improved one-class FKT (OC-FKT) for target detection. The statistical properties of target training samples are used to define tunnel-like boundary of the target class. Non-target samples are then created synthetically as to be outside of the boundary. Thus, only limited target samples become adequate for training of FKT. The hyperspectral image experiments confirm that the proposed OC-FKT technique provides an effective means for target detection.

Level 2 processing for the imaging Fourier transform spectrometer GLORIA: derivation and validation of temperature and trace gas volume mixing ratios from calibrated dynamics mode spectra

NASA Astrophysics Data System (ADS)

Ungermann, J.; Blank, J.; Dick, M.; Ebersoldt, A.; Friedl-Vallon, F.; Giez, A.; Guggenmoser, T.; Höpfner, M.; Jurkat, T.; Kaufmann, M.; Kaufmann, S.; Kleinert, A.; Krämer, M.; Latzko, T.; Oelhaf, H.; Olchewski, F.; Preusse, P.; Rolf, C.; Schillings, J.; Suminska-Ebersoldt, O.; Tan, V.; Thomas, N.; Voigt, C.; Zahn, A.; Zöger, M.; Riese, M.

2015-06-01

The Gimballed Limb Observer for Radiance Imaging of the Atmosphere (GLORIA) is an airborne infrared limb imager combining a two-dimensional infrared detector with a Fourier transform spectrometer. It was operated aboard the new German Gulfstream G550 High Altitude LOng Range (HALO) research aircraft during the Transport And Composition in the upper Troposphere/lowermost Stratosphere (TACTS) and Earth System Model Validation (ESMVAL) campaigns in summer 2012. This paper describes the retrieval of temperature and trace gas (H2O, O3, HNO3) volume mixing ratios from GLORIA dynamics mode spectra that are spectrally sampled every 0.625 cm-1. A total of 26 integrated spectral windows are employed in a joint fit to retrieve seven targets using consecutively a fast and an accurate tabulated radiative transfer model. Typical diagnostic quantities are provided including effects of uncertainties in the calibration and horizontal resolution along the line of sight. Simultaneous in situ observations by the Basic Halo Measurement and Sensor System (BAHAMAS), the Fast In-situ Stratospheric Hygrometer (FISH), an ozone detector named Fairo, and the Atmospheric chemical Ionization Mass Spectrometer (AIMS) allow a validation of retrieved values for three flights in the upper troposphere/lowermost stratosphere region spanning polar and sub-tropical latitudes. A high correlation is achieved between the remote sensing and the in situ trace gas data, and discrepancies can to a large extent be attributed to differences in the probed air masses caused by different sampling characteristics of the instruments. This 1-D processing of GLORIA dynamics mode spectra provides the basis for future tomographic inversions from circular and linear flight paths to better understand selected dynamical processes of the upper troposphere and lowermost stratosphere.

Level 2 processing for the imaging Fourier transform spectrometer GLORIA: derivation and validation of temperature and trace gas volume mixing ratios from calibrated dynamics mode spectra

NASA Astrophysics Data System (ADS)

Ungermann, J.; Blank, J.; Dick, M.; Ebersoldt, A.; Friedl-Vallon, F.; Giez, A.; Guggenmoser, T.; Höpfner, M.; Jurkat, T.; Kaufmann, M.; Kaufmann, S.; Kleinert, A.; Krämer, M.; Latzko, T.; Oelhaf, H.; Olchewski, F.; Preusse, P.; Rolf, C.; Schillings, J.; Suminska-Ebersoldt, O.; Tan, V.; Thomas, N.; Voigt, C.; Zahn, A.; Zöger, M.; Riese, M.

2014-12-01

The Gimballed Limb Observer for Radiance Imaging of the Atmosphere (GLORIA) is an airborne infrared limb-imager combining a two-dimensional infrared detector with a Fourier transform spectrometer. It was operated aboard the new German Gulfstream G550 research aircraft HALO during the Transport And Composition in the upper Troposphere/lowermost Stratosphere (TACTS) and Earth System Model Validation (ESMVAL) campaigns in summer 2012. This paper describes the retrieval of temperature and trace gas (H2O, O3, HNO3) volume mixing ratios from GLORIA dynamics mode spectra. 26 integrated spectral windows are employed in a joint fit to retrieve seven targets using consecutively a fast and an accurate tabulated radiative transfer model. Typical diagnostic quantities are provided including effects of uncertainties in the calibration and horizontal resolution along the line-of-sight. Simultaneous in-situ observations by the BAsic HALO Measurement And Sensor System (BAHAMAS), the Fast In-Situ Stratospheric Hygrometer (FISH), FAIRO, and the Atmospheric chemical Ionization Mass Spectrometer (AIMS) allow a validation of retrieved values for three flights in the upper troposphere/lowermost stratosphere region spanning polar and sub-tropical latitudes. A high correlation is achieved between the remote sensing and the in-situ trace gas data, and discrepancies can to a large fraction be attributed to differences in the probed air masses caused by different sampling characteristics of the instruments. This 1-D processing of GLORIA dynamics mode spectra provides the basis for future tomographic inversions from circular and linear flight paths to better understand selected dynamical processes of the upper troposphere and lowermost stratosphere.

SU-G-BRC-15: The Potential Clinical Significance of Dose Mapping Error for Intra- Fraction Dose Mapping for Lung Cancer Patients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sayah, N; Weiss, E; Watkins, W

Purpose: To evaluate the dose-mapping error (DME) inherent to conventional dose-mapping algorithms as a function of dose-matrix resolution. Methods: As DME has been reported to be greatest where dose-gradients overlap tissue-density gradients, non-clinical 66 Gy IMRT plans were generated for 11 lung patients with the target edge defined as the maximum 3D density gradient on the 0% (end of inhale) breathing phase. Post-optimization, Beams were copied to 9 breathing phases. Monte Carlo dose computed (with 2*2*2 mm{sup 3} resolution) on all 10 breathing phases was deformably mapped to phase 0% using the Monte Carlo energy-transfer method with congruent mass-mapping (EMCM);more » an externally implemented tri-linear interpolation method with voxel sub-division; Pinnacle’s internal (tri-linear) method; and a post-processing energy-mass voxel-warping method (dTransform). All methods used the same base displacement-vector-field (or it’s pseudo-inverse as appropriate) for the dose mapping. Mapping was also performed at 4*4*4 mm{sup 3} by merging adjacent dose voxels. Results: Using EMCM as the reference standard, no clinically significant (>1 Gy) DMEs were found for the mean lung dose (MLD), lung V20Gy, or esophagus dose-volume indices, although MLD and V20Gy were statistically different (2*2*2 mm{sup 3}). Pinnacle-to-EMCM target D98% DMEs of 4.4 and 1.2 Gy were observed ( 2*2*2 mm{sup 3}). However dTransform, which like EMCM conserves integral dose, had DME >1 Gy for one case. The root mean square RMS of the DME for the tri-linear-to- EMCM methods was lower for the smaller voxel volume for the tumor 4D-D98%, lung V20Gy, and cord D1%. Conclusion: When tissue gradients overlap with dose gradients, organs-at-risk DME was statistically significant but not clinically significant. Target-D98%-DME was deemed clinically significant for 2/11 patients (2*2*2 mm{sup 3}). Since tri-linear RMS-DME between EMCM and tri-linear was reduced at 2*2*2 mm{sup 3}, use of this resolution is recommended for dose mapping. Interpolative dose methods are sufficiently accurate for the majority of cases. J.V. Siebers receives funding support from Varian Medical Systems.« less

Restricted Field IMRT Dramatically Enhances IMRT Planning for Mesothelioma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Allen, Aaron M.; Schofield, Deborah; Hacker, Fred

2007-12-01

Purpose: To improve the target coverage and normal tissue sparing of intensity-modulated radiotherapy (IMRT) for mesothelioma after extrapleural pneumonectomy. Methods and Materials: Thirteen plans from patients previously treated with IMRT for mesothelioma were replanned using a restricted field technique. This technique was novel in two ways. It limited the entrance beams to 200{sup o} around the target and three to four beams per case had their field apertures restricted down to the level of the heart or liver to further limit the contralateral lung dose. New constraints were added that included a mean lung dose of <9.5 Gy and volumemore » receiving {>=}5 Gy of <55%. Results: In all cases, the planning target volume coverage was excellent, with an average of 97% coverage of the planning target volume by the target dose. No change was seen in the target coverage with the new technique. The heart, kidneys, and esophagus were all kept under tolerance in all cases. The average mean lung dose, volume receiving {>=}20 Gy, and volume receiving {>=}5 Gy with the new technique was 6.6 Gy, 3.0%, and 50.8%, respectively, compared with 13.8 Gy, 15%, and 90% with the previous technique (p < 0.0001 for all three comparisons). The maximal value for any case in the cohort was 8.0 Gy, 7.3%, and 57.5% for the mean lung dose, volume receiving {>=}20 Gy, and volume receiving {>=}5 Gy, respectively. Conclusion: Restricted field IMRT provides an improved method to deliver IMRT to a complex target after extrapleural pneumonectomy. An upcoming Phase I trial will provide validation of these results.« less

Testing the efficiency of plant artificial microRNAs by transient expression in Nicotiana benthamiana reveals additional action at the translational level

PubMed Central

Yu, Shi; Pilot, Guillaume

2014-01-01

Artificial microRNAs (amiRNAs) have become an important tool to assess gene functions due to their high efficiency and specificity to decrease target gene expression. Based on the observed degree of complementarity between microRNAs (miRNAs) and their targets, it was widely accepted that plant miRNAs act at the mRNA stability level, while the animal miRNAs act at the translational level. Contrary to these canonical dogmas, recent evidence suggests that both plant and animal miRNAs act at both levels. Nevertheless, it is still impossible to predict the effect of an artificial miRNA on the stability or translation of the target mRNA in plants. Consequently, identifying and discarding inefficient amiRNAs prior to stable plant transformation would help getting suppressed mutants faster and at reduced cost. We designed and tested a method using transient expression of amiRNAs and the corresponding target genes in Nicotiana benthamiana leaves to test the efficacy of amiRNAs for suppression of the target protein accumulation. The ability of the amiRNAs to suppress the target gene expression in N. benthamiana was then compared to that in stably transformed Arabidopsis. It was found that the efficacy of 16 amiRNAs, targeting a total of four genes, varied greatly. The effects of amiRNAs on target mRNA accumulation did not always correlate with target protein accumulation or the corresponding phenotypes, while a similar trend of the silencing efficacy of amiRNAs could be observed between N. benthamiana and stably transformed Arabidopsis. Our results showed that, similar to endogenous plant miRNAs, plant amiRNAs could act at the translational level, a property needed to be taken into account when testing the efficacy of individual amiRNAs. Preliminary tests in N. benthamiana can help determine which amiRNA would be the most likely to suppress target gene expression in stably transformed plants. PMID:25477887

Focusing analytes from 50 μL into 500 pL: On-chip focusing from large sample volumes using isotachophoresis.

PubMed

van Kooten, Xander F; Truman-Rosentsvit, Marianna; Kaigala, Govind V; Bercovici, Moran

2017-09-05

The use of on-chip isotachophoresis assays for diagnostic applications is often limited by the small volumes of standard microfluidic channels. Overcoming this limitation is particularly important for detection of 'discrete' biological targets (such as bacteria) at low concentrations, where the volume of processed liquid in a standard microchannel might not contain any targets. We present a novel microfluidic chip that enables ITP focusing of target analytes from initial sample volumes of 50 μL into a concentrated zone with a volume of 500 pL, corresponding to a 100,000-fold increase in mean concentration, and a 300,000-fold increase in peak concentration. We present design considerations for limiting sample dispersion in such large-volume focusing (LVF) chips and discuss the trade-off between assay time and Joule heating, which ultimately governs the scalability of LVF designs. Finally, we demonstrate a 100-fold improvement of ITP focusing performance in the LVF chip as compared to conventional microchannels, and apply this enhancement to achieve highly sensitive detection of both molecular targets (DNA, down to 10 fM) and whole bacteria (down to 100 cfu/mL).

Investigation of potential factors affecting the measurement of dew point temperature in oil-soaked transformers

NASA Astrophysics Data System (ADS)

Kraus, Adam H.

Moisture within a transformer's insulation system has been proven to degrade its dielectric strength. When installing a transformer in situ, one method used to calculate the moisture content of the transformer insulation is to measure the dew point temperature of the internal gas volume of the transformer tank. There are two instruments commercially available that are designed for dew point temperature measurement: the Alnor Model 7000 Dewpointer and the Vaisala DRYCAPRTM Hand-Held Dewpoint Meter DM70. Although these instruments perform an identical task, the design technology behind each instrument is vastly different. When the Alnor Dewpointer and Vaisala DM70 instruments are used to measure the dew point of the internal gas volume simultaneously from a pressurized transformer, their differences in dew point measurement have been observed to vary as much as 30 °F. There is minimal scientific research available that focuses on the process of measuring dew point of a gas inside a pressurized transformer, let alone this observed phenomenon. The primary objective of this work was to determine what effect certain factors potentially have on dew point measurements of a transformer's internal gas volume, in hopes of understanding the root cause of this phenomenon. Three factors that were studied include (1) human error, (2) the use of calibrated and out-of-calibration instruments, and (3) the presence of oil vapor gases in the dry air sample, and their subsequent effects on the Q-value of the sampled gas. After completing this portion of testing, none of the selected variables proved to be a direct cause of the observed discrepancies between the two instruments. The secondary objective was to validate the accuracy of each instrument as compared to its respective published range by testing against a known dew point temperature produced by a humidity generator. In a select operating range of -22 °F to -4 °F, both instruments were found to be accurate and within their specified tolerances. This temperature range is frequently encountered in oil-soaked transformers, and demonstrates that both instruments can measure accurately over a limited, yet common, range despite their different design methodologies. It is clear that there is another unknown factor present in oil-soaked transformers that is causing the observed discrepancy between these instruments. Future work will include testing on newly manufactured or rewound transformers in order to investigate other variables that could be causing this discrepancy.

SU-F-J-45: Sparing Normal Tissue with Ultra-High Dose Rate in Radiation Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Feng, Y

Purpose: To spare normal tissue by reducing the location uncertainty of a moving target, we proposed an ultra-high dose rate system and evaluated. Methods: High energy electrons generated with a linear accelerator were injected into a storage ring to be accumulated. The number of the electrons in the ring was determined based on the prescribed radiation dose. The dose was delivered within a millisecond, when an online imaging system found that the target was in the position that was consistent with that in a treatment plan. In such a short time period, the displacement of the target was negligible. Themore » margin added to the clinical target volume (CTV) could be reduced that was evaluated by comparing of volumes between CTV and ITV in 14 cases of lung stereotactic body radiation therapy (SBRT) treatments. A design of the ultra-high dose rate system was evaluated based clinical needs and the recent developments of low energy (a few MeV) electron storage ring. Results: This design of ultra-high dose rate system was feasible based on the techniques currently available. The reduction of a target volume was significant by reducing the margin that accounted the motion of the target. ∼50% volume reduction of the internal target volume (ITV) could be achieved in lung SBRT treatments. Conclusion: With this innovation of ultra-high dose rate system, the margin of target is able to be significantly reduced. It will reduce treatment time of gating and allow precisely specified gating window to improve the accuracy of dose delivering.« less

Four-Dimensional Positron Emission Tomography: Implications for Dose Painting of High-Uptake Regions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aristophanous, Michalis, E-mail: maristophanous@lroc.harvard.edu; Yap, Jeffrey T.; Killoran, Joseph H.

Purpose: To investigate the behavior of tumor subvolumes of high [18F]-fluorodeoxyglucose (FDG) uptake as seen on clinical four-dimensional (4D) FDG-positron emission tomography (PET) scans. Methods and Materials: Four-dimensional FDG-PET/computed tomography scans from 13 patients taken before radiotherapy were available. The analysis was focused on regions of high uptake that are potential dose-painting targets. A total of 17 lesions (primary tumors and lymph nodes) were analyzed. On each one of the five phases of the 4D scan a classification algorithm was applied to obtain the region of highest uptake and segment the tumor volume. We looked at the behavior of bothmore » the high-uptake subvolume, called 'Boost,' and the segmented tumor volume, called 'Target.' We measured several quantities that characterize the Target and Boost volumes and quantified correlations between them. Results: The behavior of the Target could not always predict the behavior of the Boost. The shape deformation of the Boost regions was on average 133% higher than that of the Target. The gross to internal target volume expansion was on average 27.4% for the Target and 64% for the Boost, a statistically significant difference (p < 0.05). Finally, the inhale-to-exhale phase (20%) had the highest shape deformation for the Boost regions. Conclusions: A complex relationship between the measured quantities for the Boost and Target volumes is revealed. The results suggest that in cases in which advanced therapy techniques such as dose painting are being used, a close examination of the 4D PET scan should be performed.« less

Predictors of pneumothorax following endoscopic valve therapy in patients with severe emphysema.

PubMed

Gompelmann, Daniela; Lim, Hyun-Ju; Eberhardt, Ralf; Gerovasili, Vasiliki; Herth, Felix Jf; Heussel, Claus Peter; Eichinger, Monika

2016-01-01

Endoscopic valve implantation is an effective treatment for patients with advanced emphysema. Despite the minimally invasive procedure, valve placement is associated with risks, the most common of which is pneumothorax. This study was designed to identify predictors of pneumothorax following endoscopic valve implantation. Preinterventional clinical measures (vital capacity, forced expiratory volume in 1 second, residual volume, total lung capacity, 6-minute walk test), qualitative computed tomography (CT) parameters (fissure integrity, blebs/bulla, subpleural nodules, pleural adhesions, partial atelectasis, fibrotic bands, emphysema type) and quantitative CT parameters (volume and low attenuation volume of the target lobe and the ipsilateral untreated lobe, target air trapping, ipsilateral lobe volume/hemithorax volume, collapsibility of the target lobe and the ipsilateral untreated lobe) were retrospectively evaluated in patients who underwent endoscopic valve placement (n=129). Regression analysis was performed to compare those who developed pneumothorax following valve therapy (n=46) with those who developed target lobe volume reduction without pneumothorax (n=83). Low attenuation volume% of ipsilateral untreated lobe (odds ratio [OR] =1.08, P=0.001), ipsilateral untreated lobe volume/hemithorax volume (OR =0.93, P=0.017), emphysema type (OR =0.26, P=0.018), pleural adhesions (OR =0.33, P=0.012) and residual volume (OR =1.58, P=0.012) were found to be significant predictors of pneumothorax. Fissure integrity (OR =1.16, P=0.075) and 6-minute walk test (OR =1.05, P=0.077) were also indicative of pneumothorax. The model including the aforementioned parameters predicted whether a patient would experience a pneumothorax 84% of the time (area under the curve =0.84). Clinical and CT parameters provide a promising tool to effectively identify patients at high risk of pneumothorax following endoscopic valve therapy.

Predictors of pneumothorax following endoscopic valve therapy in patients with severe emphysema

PubMed Central

Gompelmann, Daniela; Lim, Hyun-ju; Eberhardt, Ralf; Gerovasili, Vasiliki; Herth, Felix JF; Heussel, Claus Peter; Eichinger, Monika

2016-01-01

Background Endoscopic valve implantation is an effective treatment for patients with advanced emphysema. Despite the minimally invasive procedure, valve placement is associated with risks, the most common of which is pneumothorax. This study was designed to identify predictors of pneumothorax following endoscopic valve implantation. Methods Preinterventional clinical measures (vital capacity, forced expiratory volume in 1 second, residual volume, total lung capacity, 6-minute walk test), qualitative computed tomography (CT) parameters (fissure integrity, blebs/bulla, subpleural nodules, pleural adhesions, partial atelectasis, fibrotic bands, emphysema type) and quantitative CT parameters (volume and low attenuation volume of the target lobe and the ipsilateral untreated lobe, target air trapping, ipsilateral lobe volume/hemithorax volume, collapsibility of the target lobe and the ipsilateral untreated lobe) were retrospectively evaluated in patients who underwent endoscopic valve placement (n=129). Regression analysis was performed to compare those who developed pneumothorax following valve therapy (n=46) with those who developed target lobe volume reduction without pneumothorax (n=83). Finding Low attenuation volume% of ipsilateral untreated lobe (odds ratio [OR] =1.08, P=0.001), ipsilateral untreated lobe volume/hemithorax volume (OR =0.93, P=0.017), emphysema type (OR =0.26, P=0.018), pleural adhesions (OR =0.33, P=0.012) and residual volume (OR =1.58, P=0.012) were found to be significant predictors of pneumothorax. Fissure integrity (OR =1.16, P=0.075) and 6-minute walk test (OR =1.05, P=0.077) were also indicative of pneumothorax. The model including the aforementioned parameters predicted whether a patient would experience a pneumothorax 84% of the time (area under the curve =0.84). Interpretation Clinical and CT parameters provide a promising tool to effectively identify patients at high risk of pneumothorax following endoscopic valve therapy. PMID:27536088

Consequences of anorectal cancer atlas implementation in the cooperative group setting: radiobiologic analysis of a prospective randomized in silico target delineation study.

PubMed

Mavroidis, Panayiotis; Giantsoudis, Drosoula; Awan, Musaddiq J; Nijkamp, Jasper; Rasch, Coen R N; Duppen, Joop C; Thomas, Charles R; Okunieff, Paul; Jones, William E; Kachnic, Lisa A; Papanikolaou, Niko; Fuller, Clifton D

2014-09-01

The aim of this study is to ascertain the subsequent radiobiological impact of using a consensus guideline target volume delineation atlas. Using a representative case and target volume delineation instructions derived from a proposed IMRT rectal cancer clinical trial, gross tumor volume (GTV) and clinical/planning target volumes (CTV/PTV) were contoured by 13 physician observers (Phase 1). The observers were then randomly assigned to follow (atlas) or not-follow (control) a consensus guideline/atlas for anorectal cancers, and instructed to re-contour the same case (Phase 2). The atlas group was found to have increased tumor control probability (TCP) after the atlas intervention for both the CTV (p<0.0001) and PTV1 (p=0.0011) with decreasing normal tissue complication probability (NTCP) for small intestine, while the control group did not. Additionally, the atlas group had reduced variance in TCP for all target volumes and reduced variance in NTCP for the bowel. In Phase 2, the atlas group had increased TCP relative to the control for CTV (p=0.03). Visual atlas and consensus treatment guideline usage in the development of rectal cancer IMRT treatment plans reduced the inter-observer radiobiological variation, with clinically relevant TCP alteration for CTV and PTV volumes. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Method for sputtering with low frequency alternating current

DOEpatents

Timberlake, John R.

1996-01-01

Low frequency alternating current sputtering is provided by connecting a low frequency alternating current source to a high voltage transformer having outer taps and a center tap for stepping up the voltage of the alternating current. The center tap of the transformer is connected to a vacuum vessel containing argon or helium gas. Target electrodes, in close proximity to each other, and containing material with which the substrates will be coated, are connected to the outer taps of the transformer. With an applied potential, the gas will ionize and sputtering from the target electrodes onto the substrate will then result. The target electrodes can be copper or boron, and the substrate can be stainless steel, aluminum, or titanium. Copper coatings produced are used in place of nickel and/or copper striking.

Method for sputtering with low frequency alternating current

DOEpatents

Timberlake, J.R.

1996-04-30

Low frequency alternating current sputtering is provided by connecting a low frequency alternating current source to a high voltage transformer having outer taps and a center tap for stepping up the voltage of the alternating current. The center tap of the transformer is connected to a vacuum vessel containing argon or helium gas. Target electrodes, in close proximity to each other, and containing material with which the substrates will be coated, are connected to the outer taps of the transformer. With an applied potential, the gas will ionize and sputtering from the target electrodes onto the substrate will then result. The target electrodes can be copper or boron, and the substrate can be stainless steel, aluminum, or titanium. Copper coatings produced are used in place of nickel and/or copper striking. 6 figs.

CRISPR/Cas9-mediated gene targeting in Arabidopsis using sequential transformation.

PubMed

Miki, Daisuke; Zhang, Wenxin; Zeng, Wenjie; Feng, Zhengyan; Zhu, Jian-Kang

2018-05-17

Homologous recombination-based gene targeting is a powerful tool for precise genome modification and has been widely used in organisms ranging from yeast to higher organisms such as Drosophila and mouse. However, gene targeting in higher plants, including the most widely used model plant Arabidopsis thaliana, remains challenging. Here we report a sequential transformation method for gene targeting in Arabidopsis. We find that parental lines expressing the bacterial endonuclease Cas9 from the egg cell- and early embryo-specific DD45 gene promoter can improve the frequency of single-guide RNA-targeted gene knock-ins and sequence replacements via homologous recombination at several endogenous sites in the Arabidopsis genome. These heritable gene targeting can be identified by regular PCR. Our approach enables routine and fine manipulation of the Arabidopsis genome.

Radiation therapy for breast cancer: Literature review

DOE Office of Scientific and Technical Information (OSTI.GOV)

Balaji, Karunakaran, E-mail: karthik.balaji85@gmail.com; School of Advanced Sciences, VIT University, Vellore; Subramanian, Balaji

Concave shape with variable size target volume makes treatment planning for the breast/chest wall a challenge. Conventional techniques used for the breast/chest wall cancer treatment provided better sparing of organs at risk (OARs), with poor conformity and uniformity to the target volume. Advanced technologies such as intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) improve the target coverage at the cost of higher low dose volumes to OARs. Novel hybrid techniques present promising results in breast/chest wall irradiation in terms of target coverage as well as OARs sparing. Several published data compared these technologies for the benefit ofmore » the breast/chest wall with or without nodal volumes. The aim of this article is to review relevant data and identify the scope for further research in developing optimal treatment plan for breast/chest wall cancer treatment.« less

Accommodating High Transformation Strains in Battery Electrodes via the Formation of Nanoscale Intermediate Phases: Operando Investigation of Olivine NaFePO 4 [Accommodation of High Transformation Strain in Battery Electrodes via Formation of Nanoscale Intermediate Phases: Operando Structure Investigation of Olivine Sodium Iron Phosphate

DOE PAGES

Xiang, Kai; Xing, Wenting; Ravnsbaek, Dorthe B.; ...

2017-02-21

Virtually all intercalation compounds used as battery electrodes exhibit significant changes in unit cell volume during use. Na xFePO 4 (0 < x < 1, NFP) olivine, of interest as a cathode for sodium-ion batteries, is a model for topotactic, high strain systems as it exhibits one of the largest discontinuous volume changes (~17% by volume) during its first-order transition between two otherwise isostructural phases. Using synchrotron radiation powder X-ray diffraction (PXD) and pair distribution function (PDF) analysis, we discover a new strain-accommodation mechanism wherein a third, <10 nm scale nanocrystalline phase forms to buffer the large lattice mismatch betweenmore » primary phases. The new phase has a and b lattice parameters matching one crystalline endmember phase and c lattice parameter matching the other, and is not detectable by powder diffraction alone. Finally, we suggest that this strain-accommodation mechanism may apply to systems with large transformation strains but in which true “amorphization” does not occur.« less

Accommodating High Transformation Strains in Battery Electrodes via the Formation of Nanoscale Intermediate Phases: Operando Investigation of Olivine NaFePO 4 [Accommodation of High Transformation Strain in Battery Electrodes via Formation of Nanoscale Intermediate Phases: Operando Structure Investigation of Olivine Sodium Iron Phosphate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xiang, Kai; Xing, Wenting; Ravnsbaek, Dorthe B.

Virtually all intercalation compounds used as battery electrodes exhibit significant changes in unit cell volume during use. Na xFePO 4 (0 < x < 1, NFP) olivine, of interest as a cathode for sodium-ion batteries, is a model for topotactic, high strain systems as it exhibits one of the largest discontinuous volume changes (~17% by volume) during its first-order transition between two otherwise isostructural phases. Using synchrotron radiation powder X-ray diffraction (PXD) and pair distribution function (PDF) analysis, we discover a new strain-accommodation mechanism wherein a third, <10 nm scale nanocrystalline phase forms to buffer the large lattice mismatch betweenmore » primary phases. The new phase has a and b lattice parameters matching one crystalline endmember phase and c lattice parameter matching the other, and is not detectable by powder diffraction alone. Finally, we suggest that this strain-accommodation mechanism may apply to systems with large transformation strains but in which true “amorphization” does not occur.« less

Planning 4D intensity-modulated arc therapy for tumor tracking with a multileaf collimator

NASA Astrophysics Data System (ADS)

Niu, Ying; Betzel, Gregory T.; Yang, Xiaocheng; Gui, Minzhi; Parke, William C.; Yi, Byongyong; Yu, Cedric X.

2017-02-01

This study introduces a practical four-dimensional (4D) planning scheme of IMAT using 4D computed tomography (4D CT) for planning tumor tracking with dynamic multileaf beam collimation. We assume that patients can breathe regularly, i.e. the same way as during 4D CT with an unchanged period and amplitude, and that the start of 4D-IMAT delivery can be synchronized with a designated respiratory phase. Each control point of the IMAT-delivery process can be associated with an image set of 4D CT at a specified respiratory phase. Target is contoured at each respiratory phase without a motion-induced margin. A 3D-IMAT plan is first optimized on a reference-phase image set of 4D CT. Then, based on the projections of the planning target volume in the beam’s eye view at different respiratory phases, a 4D-IMAT plan is generated by transforming the segments of the optimized 3D plan by using a direct aperture deformation method. Compensation for both translational and deformable tumor motion is accomplished, and the smooth delivery of the transformed plan is ensured by forcing connectivity between adjacent angles (control points). It is envisioned that the resultant plans can be delivered accurately using the dose rate regulated tracking method which handles breathing irregularities (Yi et al 2008 Med. Phys. 35 3955-62).This planning process is straightforward and only adds a small step to current clinical 3D planning practice. Our 4D planning scheme was tested on three cases to evaluate dosimetric benefits. The created 4D-IMAT plans showed similar dose distributions as compared with the 3D-IMAT plans on a single static phase, indicating that our method is capable of eliminating the dosimetric effects of breathing induced target motion. Compared to the 3D-IMAT plans with large treatment margins encompassing respiratory motion, our 4D-IMAT plans reduced radiation doses to surrounding normal organs and tissues.

Transformational and derivational strategies in analogical problem solving.

PubMed

Schelhorn, Sven-Eric; Griego, Jacqueline; Schmid, Ute

2007-03-01

Analogical problem solving is mostly described as transfer of a source solution to a target problem based on the structural correspondences (mapping) between source and target. Derivational analogy (Carbonell, Machine learning: an artificial intelligence approach Los Altos. Morgan Kaufmann, 1986) proposes an alternative view: a target problem is solved by replaying a remembered problem-solving episode. Thus, the experience with the source problem is used to guide the search for the target solution by applying the same solution technique rather than by transferring the complete solution. We report an empirical study using the path finding problems presented in Novick and Hmelo (J Exp Psychol Learn Mem Cogn 20:1296-1321, 1994) as material. We show that both transformational and derivational analogy are problem-solving strategies realized by human problem solvers. Which strategy is evoked in a given problem-solving context depends on the constraints guiding object-to-object mapping between source and target problem. Specifically, if constraints facilitating mapping are available, subjects are more likely to employ a transformational strategy, otherwise they are more likely to use a derivational strategy.

Transformation: Building a New Society. Through Chinese Eyes, Volume 2. Revised Edition.

ERIC Educational Resources Information Center

Seybolt, Peter J.; Clark, Leon E., Ed.

A Chinese view of China and the world is presented in this book, which is second in a series of two volumes which can be used in secondary and college courses. The reality of everyday life as experienced by the Chinese people is recreated in the series. Almost all of the material in both volumes has been written by Chinese and has been taken from…

Application of multivariate Gaussian detection theory to known non-Gaussian probability density functions

NASA Astrophysics Data System (ADS)

Schwartz, Craig R.; Thelen, Brian J.; Kenton, Arthur C.

1995-06-01

A statistical parametric multispectral sensor performance model was developed by ERIM to support mine field detection studies, multispectral sensor design/performance trade-off studies, and target detection algorithm development. The model assumes target detection algorithms and their performance models which are based on data assumed to obey multivariate Gaussian probability distribution functions (PDFs). The applicability of these algorithms and performance models can be generalized to data having non-Gaussian PDFs through the use of transforms which convert non-Gaussian data to Gaussian (or near-Gaussian) data. An example of one such transform is the Box-Cox power law transform. In practice, such a transform can be applied to non-Gaussian data prior to the introduction of a detection algorithm that is formally based on the assumption of multivariate Gaussian data. This paper presents an extension of these techniques to the case where the joint multivariate probability density function of the non-Gaussian input data is known, and where the joint estimate of the multivariate Gaussian statistics, under the Box-Cox transform, is desired. The jointly estimated multivariate Gaussian statistics can then be used to predict the performance of a target detection algorithm which has an associated Gaussian performance model.

Toward frameless stereotaxy: anatomical-vascular correlation and registration

NASA Astrophysics Data System (ADS)

Henri, Christopher J.; Cukiert, A.; Collins, D. Louis; Olivier, A.; Peters, Terence M.

1992-09-01

We present a method to correlate and register a projection angiogram with volume rendered tomographic data from the same patient. Previously, we have described how this may be accomplished using a stereotactic frame to handle the required coordinate transformations. Here we examine the efficacy of employing anatomically based landmarks as opposed to external fiducials to achieve the same results. The experiments required a neurosurgeon to identify several homologous points in a DSA image and a MRI volume which were subsequently used to compute the coordinate transformations governing the matching procedure. Correlation accuracy was assessed by comparing these results to those employing fiducial markers on a stereotactic frame, and by examining how different levels of noise in the positions of the homologous points affect the resulting coordinate transformations. Further simulations suggest that this method has potential to be used in planning stereotactic procedures without the use of a frame.

Reaching Potentials: Transforming Early Childhood Curriculum and Assessment. Volume 2.

ERIC Educational Resources Information Center

Bredekamp, Sue, Ed.; Rosegrant, Teresa, Ed.

This book builds on Volume 1 of "Reaching Potentials," which attempted to operationalize the "Guidelines for Appropriate Curriculum Content and Assessment" set by the National Association for the Education of Young Children (NAEYC) and the National Association of Early Childhood Specialists in State Departments of Education…

Big as Life: The Everyday Inclusive Curriculum. Volume 2.

ERIC Educational Resources Information Center

York, Stacey

This guide is intended to assist early childhood teachers in integrating multicultural, anti-bias education into the curriculum. Following an introduction discussing the goals and elements of a transformative curriculum, Part 1 of this volume presents curriculum units on animals, community, foods, friends, heroes and "sheroes," money,…

Critical Qualitative Research Reader. Critical Qualitative Research. Volume 2

ERIC Educational Resources Information Center

Steinberg, Shirley R., Ed.; Cannella, Gaile S., Ed.

2012-01-01

This volume of transformed research utilizes an activist approach to examine the notion that nothing is apolitical. Research projects themselves are critically examined for power orientations, even as they are used to address curricular problems and educational or societal issues. Philosophical perspectives that have facilitated an understanding…

Development of a Solid Phase Extraction Method for Agricultural Pesticides in Large-Volume Water Samples

EPA Science Inventory

An analytical method using solid phase extraction (SPE) and analysis by gas chromatography/mass spectrometry (GC/MS) was developed for the trace determination of a variety of agricultural pesticides and selected transformation products in large-volume high-elevation lake water sa...

American Higher Education Transformed, 1940-2005: Documenting the National Discourse

ERIC Educational Resources Information Center

Smith, Wilson, Ed.; Bender, Thomas, Ed.

2008-01-01

This long-awaited sequel to Richard Hofstadter and Wilson Smith's classic anthology "American Higher Education: A Documentary History" presents one hundred and seventy-two key edited documents that record the transformation of higher education over the past sixty years. The volume includes such seminal documents as Vannevar Bush's 1945…

RISK OF UNSATURATED/SATURATED TRANSPORT AND TRANSFORMATION OF CHEMICAL CONCENTRATIONS (RUSTIC): VOLUME 1. THEORY AND CODE VERIFICATION

EPA Science Inventory

The RUSTIC program links three subordinate models--PRZM, VADOFT, and SAFTMOD--in order to predict pesticide transport and transformation through the crop root zone, the unsaturated zone, and the saturated zone to drinking water wells. PRZM is a one-dimensional finite-difference m...

Preliminary experience with a novel method of three-dimensional co-registration of prostate cancer digital histology and in vivo multiparametric MRI.

PubMed

Orczyk, C; Rusinek, H; Rosenkrantz, A B; Mikheev, A; Deng, F-M; Melamed, J; Taneja, S S

2013-12-01

To assess a novel method of three-dimensional (3D) co-registration of prostate cancer digital histology and in-vivo multiparametric magnetic resonance imaging (mpMRI) image sets for clinical usefulness. A software platform was developed to achieve 3D co-registration. This software was prospectively applied to three patients who underwent radical prostatectomy. Data comprised in-vivo mpMRI [T2-weighted, dynamic contrast-enhanced weighted images (DCE); apparent diffusion coefficient (ADC)], ex-vivo T2-weighted imaging, 3D-rebuilt pathological specimen, and digital histology. Internal landmarks from zonal anatomy served as reference points for assessing co-registration accuracy and precision. Applying a method of deformable transformation based on 22 internal landmarks, a 1.6 mm accuracy was reached to align T2-weighted images and the 3D-rebuilt pathological specimen, an improvement over rigid transformation of 32% (p = 0.003). The 22 zonal anatomy landmarks were more accurately mapped using deformable transformation than rigid transformation (p = 0.0008). An automatic method based on mutual information, enabled automation of the process and to include perfusion and diffusion MRI images. Evaluation of co-registration accuracy using the volume overlap index (Dice index) met clinically relevant requirements, ranging from 0.81-0.96 for sequences tested. Ex-vivo images of the specimen did not significantly improve co-registration accuracy. This preliminary analysis suggests that deformable transformation based on zonal anatomy landmarks is accurate in the co-registration of mpMRI and histology. Including diffusion and perfusion sequences in the same 3D space as histology is essential further clinical information. The ability to localize cancer in 3D space may improve targeting for image-guided biopsy, focal therapy, and disease quantification in surveillance protocols. Copyright © 2013 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

Performance comparison of ISAR imaging method based on time frequency transforms

NASA Astrophysics Data System (ADS)

Xie, Chunjian; Guo, Chenjiang; Xu, Jiadong

2013-03-01

Inverse synthetic aperture radar (ISAR) can image the moving target, especially the target in the air, so it is important in the air defence and missile defence system. Time-frequency Transform was applied to ISAR imaging process widely. Several time frequency transforms were introduced. Noise jamming methods were analysed, and when these noise jamming were added to the echo of the ISAR receiver, the image can become blur even can't to be identify. But the effect is different to the different time frequency analysis. The results of simulation experiment show the Performance Comparison of the method.

Infrared small target detection with kernel Fukunaga Koontz transform

NASA Astrophysics Data System (ADS)

Liu, Rui-ming; Liu, Er-qi; Yang, Jie; Zhang, Tian-hao; Wang, Fang-lin

2007-09-01

The Fukunaga-Koontz transform (FKT) has been proposed for many years. It can be used to solve two-pattern classification problems successfully. However, there are few researchers who have definitely extended FKT to kernel FKT (KFKT). In this paper, we first complete this task. Then a method based on KFKT is developed to detect infrared small targets. KFKT is a supervised learning algorithm. How to construct training sets is very important. For automatically detecting targets, the synthetic target images and real background images are used to train KFKT. Because KFKT can represent the higher order statistical properties of images, we expect better detection performance of KFKT than that of FKT. The well-devised experiments verify that KFKT outperforms FKT in detecting infrared small targets.

Activation of antioxidant pathways in ras-mediated oncogenic transformation of human surface ovarian epithelial cells revealed by functional proteomics and mass spectrometry.

PubMed

Young, Travis W; Mei, Fang C; Yang, Gong; Thompson-Lanza, Jennifer A; Liu, Jinsong; Cheng, Xiaodong

2004-07-01

Cellular transformation is a complex process involving genetic alterations associated with multiple signaling pathways. Development of a transformation model using defined genetic elements has provided an opportunity to elucidate the role of oncogenes and tumor suppressor genes in the initiation and development of ovarian cancer. To study the cellular and molecular mechanisms of Ras-mediated oncogenic transformation of ovarian epithelial cells, we used a proteomic approach involving two-dimensional electrophoresis and mass spectrometry to profile two ovarian epithelial cell lines, one immortalized with SV40 T/t antigens and the human catalytic subunit of telomerase and the other transformed with an additional oncogenic ras(V12) allele. Of approximately 2200 observed protein spots, we have identified >30 protein targets that showed significant changes between the immortalized and transformed cell lines using peptide mass fingerprinting. Among these identified targets, one most notable group of proteins altered significantly consists of enzymes involved in cellular redox balance. Detailed analysis of these protein targets suggests that activation of Ras-signaling pathways increases the threshold of reactive oxidative species (ROS) tolerance by up-regulating the overall antioxidant capacity of cells, especially in mitochondria. This enhanced antioxidant capacity protects the transformed cells from high levels of ROS associated with the uncontrolled growth potential of tumor cells. It is conceivable that an enhanced antioxidation capability may constitute a common mechanism for tumor cells to evade apoptosis induced by oxidative stresses at high ROS levels.

Prospective feasibility trial of radiotherapy target definition for head and neck cancer using 3-dimensional PET and CT imaging.

PubMed

Scarfone, Christopher; Lavely, William C; Cmelak, Anthony J; Delbeke, Dominique; Martin, William H; Billheimer, Dean; Hallahan, Dennis E

2004-04-01

The aim of this investigation was to evaluate the influence and accuracy of (18)F-FDG PET in target volume definition as a complementary modality to CT for patients with head and neck cancer (HNC) using dedicated PET and CT scanners. Six HNC patients were custom fitted with head and neck and upper body immobilization devices, and conventional radiotherapy CT simulation was performed together with (18)F-FDG PET imaging. Gross target volume (GTV) and pathologic nodal volumes were first defined in the conventional manner based on CT. A segmentation and surface-rendering registration technique was then used to coregister the (18)F-FDG PET and CT planning image datasets. (18)F-FDG PET GTVs were determined and displayed simultaneously with the CT contours. CT GTVs were then modified based on the PET data to form final PET/CT treatment volumes. Five-field intensity-modulated radiation therapy (IMRT) was then used to demonstrate dose targeting to the CT GTV or the PET/CT GTV. One patient was PET-negative after induction chemotherapy. The CT GTV was modified in all remaining patients based on (18)F-FDG PET data. The resulting PET/CT GTV was larger than the original CT volume by an average of 15%. In 5 cases, (18)F-FDG PET identified active lymph nodes that corresponded to lymph nodes contoured on CT. The pathologically enlarged CT lymph nodes were modified to create final lymph node volumes in 3 of 5 cases. In 1 of 6 patients, (18)F-FDG-avid lymph nodes were not identified as pathologic on CT. In 2 of 6 patients, registration of the independently acquired PET and CT data using segmentation and surface rendering resulted in a suboptimal alignment and, therefore, had to be repeated. Radiotherapy planning using IMRT demonstrated the capability of this technique to target anatomic or anatomic/physiologic target volumes. In this manner, metabolically active sites can be intensified to greater daily doses. Inclusion of (18)F-FDG PET data resulted in modified target volumes in radiotherapy planning for HNC. PET and CT data acquired on separate, dedicated scanners may be coregistered for therapy planning; however, dual-acquisition PET/CT systems may be considered to reduce the need for reregistrations. It is possible to use IMRT to target dose to metabolically active sites based on coregistered PET/CT data.

Improving observational study estimates of treatment effects using joint modeling of selection effects and outcomes: the case of AAA repair.

PubMed

O'Malley, A James; Cotterill, Philip; Schermerhorn, Marc L; Landon, Bruce E

2011-12-01

When 2 treatment approaches are available, there are likely to be unmeasured confounders that influence choice of procedure, which complicates estimation of the causal effect of treatment on outcomes using observational data. To estimate the effect of endovascular (endo) versus open surgical (open) repair, including possible modification by institutional volume, on survival after treatment for abdominal aortic aneurysm, accounting for observed and unobserved confounding variables. Observational study of data from the Medicare program using a joint model of treatment selection and survival given treatment to estimate the effects of type of surgery and institutional volume on survival. We studied 61,414 eligible repairs of intact abdominal aortic aneurysms during 2001 to 2004. The outcome, perioperative death, is defined as in-hospital death or death within 30 days of operation. The key predictors are use of endo, transformed endo and open volume, and endo-volume interactions. There is strong evidence of nonrandom selection of treatment with potential confounding variables including institutional volume and procedure date, variables not typically adjusted for in clinical trials. The best fitting model included heterogeneous transformations of endo volume for endo cases and open volume for open cases as predictors. Consistent with our hypothesis, accounting for unmeasured selection reduced the mortality benefit of endo. The effect of endo versus open surgery varies nonlinearly with endo and open volume. Accounting for institutional experience and unmeasured selection enables better decision-making by physicians making treatment referrals, investigators evaluating treatments, and policy makers.

An automated landmark-based elastic registration technique for large deformation recovery from 4-D CT lung images

NASA Astrophysics Data System (ADS)

Negahdar, Mohammadreza; Zacarias, Albert; Milam, Rebecca A.; Dunlap, Neal; Woo, Shiao Y.; Amini, Amir A.

2012-03-01

The treatment plan evaluation for lung cancer patients involves pre-treatment and post-treatment volume CT imaging of the lung. However, treatment of the tumor volume lung results in structural changes to the lung during the course of treatment. In order to register the pre-treatment volume to post-treatment volume, there is a need to find robust and homologous features which are not affected by the radiation treatment along with a smooth deformation field. Since airways are well-distributed in the entire lung, in this paper, we propose use of airway tree bifurcations for registration of the pre-treatment volume to the post-treatment volume. A dedicated and automated algorithm has been developed that finds corresponding airway bifurcations in both images. To derive the 3-D deformation field, a B-spline transformation model guided by mutual information similarity metric was used to guarantee the smoothness of the transformation while combining global information from bifurcation points. Therefore, the approach combines both global statistical intensity information with local image feature information. Since during normal breathing, the lung undergoes large nonlinear deformations, it is expected that the proposed method would also be applicable to large deformation registration between maximum inhale and maximum exhale images in the same subject. The method has been evaluated by registering 3-D CT volumes at maximum exhale data to all the other temporal volumes in the POPI-model data.

Cluster State Quantum Computation

DTIC Science & Technology

2014-02-01

information of relevance to the transformation. We define the fidelity as the probability that the desired target gate ATar has been faithfully...implemented on the computational modes given a successful measurement of the ancilla modes: 2 , (3) since Tr ( ATar † ATar )=2Mc for a properly normalized...photonic gates The optimization method we have developed maximizes the success probability S for a given target transformation ATar , for given

Intracranial stereotactic radiosurgery with an adapted linear accelerator vs. robotic radiosurgery: Comparison of dosimetric treatment plan quality.

PubMed

Treuer, Harald; Hoevels, Moritz; Luyken, Klaus; Visser-Vandewalle, Veerle; Wirths, Jochen; Kocher, Martin; Ruge, Maximilian

2015-06-01

Stereotactic radiosurgery with an adapted linear accelerator (linac-SRS) is an established therapy option for brain metastases, benign brain tumors, and arteriovenous malformations. We intended to investigate whether the dosimetric quality of treatment plans achieved with a CyberKnife (CK) is at least equivalent to that for linac-SRS with circular or micromultileaf collimators (microMLC). A random sample of 16 patients with 23 target volumes, previously treated with linac-SRS, was replanned with CK. Planning constraints were identical dose prescription and clinical applicability. In all cases uniform optimization scripts and inverse planning objectives were used. Plans were compared with respect to coverage, minimal dose within target volume, conformity index, and volume of brain tissue irradiated with ≥ 10 Gy. Generating the CK plan was unproblematic with simple optimization scripts in all cases. With the CK plans, coverage, minimal target volume dosage, and conformity index were significantly better, while no significant improvement could be shown regarding the 10 Gy volume. Multiobjective comparison for the irradiated target volumes was superior in the CK plan in 20 out of 23 cases and equivalent in 3 out of 23 cases. Multiobjective comparison for the treated patients was superior in the CK plan in all 16 cases. The results clearly demonstrate the superiority of the irradiation plan for CK compared to classical linac-SRS with circular collimators and microMLC. In particular, the average minimal target volume dose per patient, increased by 1.9 Gy, and at the same time a 14% better conformation index seems to be an improvement with clinical relevance.

Kinome screening for regulators of the estrogen receptor identifies LMTK3 as a new therapeutic target in breast cancer.

PubMed

Giamas, Georgios; Filipović, Aleksandra; Jacob, Jimmy; Messier, Walter; Zhang, Hua; Yang, Dongyun; Zhang, Wu; Shifa, Belul Assefa; Photiou, Andrew; Tralau-Stewart, Cathy; Castellano, Leandro; Green, Andrew R; Coombes, R Charles; Ellis, Ian O; Ali, Simak; Lenz, Heinz-Josef; Stebbing, Justin

2011-06-01

Therapies targeting estrogen receptor α (ERα, encoded by ESR1) have transformed the treatment of breast cancer. However, large numbers of women relapse, highlighting the need for the discovery of new regulatory targets modulating ERα pathways. An siRNA screen identified kinases whose silencing alters the estrogen response including those previously implicated in regulating ERα activity (such as mitogen-activated protein kinase and AKT). Among the most potent regulators was lemur tyrosine kinase-3 (LMTK3), for which a role has not previously been assigned. In contrast to other modulators of ERα activity, LMTK3 seems to have been subject to Darwinian positive selection, a noteworthy result given the unique susceptibility of humans to ERα+ breast cancer. LMTK3 acts by decreasing the activity of protein kinase C (PKC) and the phosphorylation of AKT (Ser473), thereby increasing binding of forkhead box O3 (FOXO3) to the ESR1 promoter. LMTK3 phosphorylated ERα, protecting it from proteasomal degradation in vitro. Silencing of LMTK3 reduced tumor volume in an orthotopic mouse model and abrogated proliferation of ERα+ but not ERα- cells, indicative of its role in ERα activity. In human cancers, LMTK3 abundance and intronic polymorphisms were significantly associated with disease-free and overall survival and predicted response to endocrine therapies. These findings yield insights into the natural history of breast cancer in humans and reveal LMTK3 as a new therapeutic target.

Hemorrhagic transformation in patients with acute ischaemic stroke and an indication for anticoagulation.

PubMed

Marsh, E B; Llinas, R H; Hillis, A E; Gottesman, R F

2013-06-01

Intracerebral hemorrhage (ICH) can occur in patients following acute ischaemic stroke in the form of hemorrhagic transformation, and results in significant long-term morbidity and mortality. Anticoagulation theoretically increases risk. We evaluated stroke patients with an indication for anticoagulation to determine the factors associated with hemorrhagic transformation. Three-hundred and forty-five patients with ICD-9 codes indicating: (i) acute ischaemic stroke; and (ii) an indication for anticoagulation were screened. One-hundred and twenty-three met inclusion criteria. Data were collected retrospectively. Neuroimaging was reviewed for infarct volume and evidence of ICH. Hemorrhages were classified as: hemorrhagic conversion (petechiae) versus intracerebral hematoma (a space occupying lesion); symptomatic versus asymptomatic. Using multivariable logistic regression, we determined the hypothesized factors associated with intracerebral bleeding. Age [odds ratio (OR) = 1.50 per 10-year increment, 95% confidence interval (CI) 1.07-2.08], infarct volume (OR = 1.10 per 10 ccs, 95% CI 1.06-1.18) and worsening category of renal impairment by estimated glomerular filtration rate (eGFR; OR = 1.95, 95% CI 1.04-3.66) were predictors of hemorrhagic transformation. Ninety- nine out of 123 patients were anticoagulated. Hemorrhage rates of patients on and off anticoagulation did not differ (25.3% vs. 20.8%; P = 0.79); however, all intracerebral hematomas (n = 7) and symptomatic bleeds (n = 8) occurred in the anticoagulated group. The risk of hemorrhagic transformation in patients with acute ischaemic stroke and an indication for anticoagulation is multifactorial, and most closely associated with an individual's age, infarct volume and eGFR. © 2013 The Author(s) European Journal of Neurology © 2013 EFNS.

CF3DODA-Me induces apoptosis, degrades Sp1, and blocks the transformation phase of the blebbishield emergency program.

PubMed

Taoka, Rikiya; Jinesh, Goodwin G; Xue, Wenrui; Safe, Stephen; Kamat, Ashish M

2017-05-01

Cancer stem cells are capable of undergoing cellular transformation after commencement of apoptosis through the blebbishield emergency program in a VEGF-VEGFR2-dependent manner. Development of therapeutics targeting the blebbishield emergency program would thus be important in cancer therapy. Specificity protein 1 (Sp1) orchestrates the transcription of both VEGF and VEGFR2; hence, Sp1 could act as a therapeutic target. Here, we demonstrate that CF 3 DODA-Me induced apoptosis, degraded Sp1, inhibited the expression of multiple drivers of the blebbishield emergency program such as VEGFR2, p70S6K, and N-Myc through activation of caspase-3, inhibited reactive oxygen species; and inhibited K-Ras activation to abolish transformation from blebbishields as well as transformation in soft agar. These findings confirm CF 3 DODA-Me as a potential therapeutic candidate that can induce apoptosis and block transformation from blebbishields.

A novel earth observation based ecological indicator for cyanobacterial blooms

NASA Astrophysics Data System (ADS)

Anttila, Saku; Fleming-Lehtinen, Vivi; Attila, Jenni; Junttila, Sofia; Alasalmi, Hanna; Hällfors, Heidi; Kervinen, Mikko; Koponen, Sampsa

2018-02-01

Cyanobacteria form spectacular mass occurrences almost annually in the Baltic Sea. These harmful algal blooms are the most visible consequences of marine eutrophication, driven by a surplus of nutrients from anthropogenic sources and internal processes of the ecosystem. We present a novel Cyanobacterial Bloom Indicator (CyaBI) targeted for the ecosystem assessment of eutrophication in marine areas. The method measures the current cyanobacterial bloom situation (an average condition of recent 5 years) and compares this to the estimated target level for 'good environmental status' (GES). The current status is derived with an index combining indicative bloom event variables. As such we used seasonal information from the duration, volume and severity of algal blooms derived from earth observation (EO) data. The target level for GES was set by using a remote sensing based data set named Fraction with Cyanobacterial Accumulations (FCA; Kahru & Elmgren, 2014) covering years 1979-2014. Here a shift-detection algorithm for time series was applied to detect time-periods in the FCA data where the level of blooms remained low several consecutive years. The average conditions from these time periods were transformed into respective CyaBI target values to represent target level for GES. The indicator is shown to pass the three critical factors set for marine indicator development, namely it measures the current status accurately, the target setting can be scientifically proven and it can be connected to the ecosystem management goal. An advantage of the CyaBI method is that it's not restricted to the data used in the development work, but can be complemented, or fully applied, by using different types of data sources providing information on cyanobacterial accumulations.

Functional Requirements of a Target Description System for Vulnerability Analysis

DTIC Science & Technology

1979-11-01

called GIFT .1,2 Together the COMGEOM description model and GIFT codes make up the BRL’s target description system. The significance of a target...and modifying target descriptions are described. 1 Lawrence W. Bain, Jr. and Mathew J. Reisinger, "The GIFT Code User Manual; Volume 1...34The GIFT Code User Manual; Volume II, The Output Options," unpublished draft of BRL report. II. UNDERLYING PHILOSOPHY The BRL has a computer

Successful transient expression of Cas9 and single guide RNA genes in Chlamydomonas reinhardtii.

PubMed

Jiang, Wenzhi; Brueggeman, Andrew J; Horken, Kempton M; Plucinak, Thomas M; Weeks, Donald P

2014-11-01

The clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9 system has become a powerful and precise tool for targeted gene modification (e.g., gene knockout and gene replacement) in numerous eukaryotic organisms. Initial attempts to apply this technology to a model, the single-cell alga, Chlamydomonas reinhardtii, failed to yield cells containing edited genes. To determine if the Cas9 and single guide RNA (sgRNA) genes were functional in C. reinhardtii, we tested the ability of a codon-optimized Cas9 gene along with one of four different sgRNAs to cause targeted gene disruption during a 24-h period immediately following transformation. All three exogenously supplied gene targets as well as the endogenous FKB12 (rapamycin sensitivity) gene of C. reinhardtii displayed distinct Cas9/sgRNA-mediated target site modifications as determined by DNA sequencing of cloned PCR amplicons of the target site region. Success in transient expression of Cas9 and sgRNA genes contrasted with the recovery of only a single rapamycin-resistant colony bearing an appropriately modified FKB12 target site in 16 independent transformation experiments involving >10(9) cells. Failure to recover transformants with intact or expressed Cas9 genes following transformation with the Cas9 gene alone (or even with a gene encoding a Cas9 lacking nuclease activity) provided strong suggestive evidence for Cas9 toxicity when Cas9 is produced constitutively in C. reinhardtii. The present results provide compelling evidence that Cas9 and sgRNA genes function properly in C. reinhardtii to cause targeted gene modifications and point to the need for a focus on development of methods to properly stem Cas9 production and/or activity following gene editing. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

A Hough Transform Global Probabilistic Approach to Multiple-Subject Diffusion MRI Tractography

PubMed Central

Aganj, Iman; Lenglet, Christophe; Jahanshad, Neda; Yacoub, Essa; Harel, Noam; Thompson, Paul M.; Sapiro, Guillermo

2011-01-01

A global probabilistic fiber tracking approach based on the voting process provided by the Hough transform is introduced in this work. The proposed framework tests candidate 3D curves in the volume, assigning to each one a score computed from the diffusion images, and then selects the curves with the highest scores as the potential anatomical connections. The algorithm avoids local minima by performing an exhaustive search at the desired resolution. The technique is easily extended to multiple subjects, considering a single representative volume where the registered high-angular resolution diffusion images (HARDI) from all the subjects are non-linearly combined, thereby obtaining population-representative tracts. The tractography algorithm is run only once for the multiple subjects, and no tract alignment is necessary. We present experimental results on HARDI volumes, ranging from simulated and 1.5T physical phantoms to 7T and 4T human brain and 7T monkey brain datasets. PMID:21376655

Transformation volume effect on the magnetic anisotropy of Ni-Mn-Ga thin films

NASA Astrophysics Data System (ADS)

L'vov, V. A.; Golub, V.; Salyuk, O.; Barandiarán, J. M.; Chernenko, V. A.

2015-01-01

Ni-Mn-Ga ferromagnetic shape memory films with similar thickness and chemical composition, deposited onto cold (with a subsequent annealing) and hot MgO(001) substrates exhibit different internal stress and structure giving rise to a different orientation of the magnetic easy axes. A quantitative theoretical analysis of the crystallographic and ferromagnetic resonance (FMR) data shows that the different anisotropies can be caused by the difference in sign between the transformation volume changes in these films, as influenced by the internal stresses. To explain FMR data, the magnetoelastic coupling term of fourth-order in the magnetic vector and linear in the strain tensor components, appearing in the Landau expansion for the free energy, is taken into account. The coefficient of the term, which couples the magnetic vector components with the volume change of the Ni-Mn-Ga alloy, was estimated to be equal to about 10 7 erg cm - 3 .

Generation of Parametric Equivalent-Area Targets for Design of Low-Boom Supersonic Concepts

NASA Technical Reports Server (NTRS)

Li, Wu; Shields, Elwood

2011-01-01

A tool with an Excel visual interface is developed to generate equivalent-area (A(sub e)) targets that satisfy the volume constraints for a low-boom supersonic configuration. The new parametric Ae target explorer allows users to interactively study the tradeoffs between the aircraft volume constraints and the low-boom characteristics (e.g., loudness) of the ground signature. Moreover, numerical optimization can be used to generate the optimal A(sub e) target for given A(sub e) volume constraints. A case study is used to demonstrate how a generated low-boom Ae target can be matched by a supersonic configuration that includes a fuselage, wing, nacelle, pylon, aft pod, horizontal tail, and vertical tail. The low-boom configuration is verified by sonic-boom analysis with an off-body pressure distribution at three body lengths below the configuration

Trans-Membrane Area Asymmetry Controls the Shape of Cellular Organelles

PubMed Central

Beznoussenko, Galina V.; Pilyugin, Sergei S.; Geerts, Willie J. C.; Kozlov, Michael M.; Burger, Koert N. J.; Luini, Alberto; Derganc, Jure; Mironov, Alexander A.

2015-01-01

Membrane organelles often have complicated shapes and differ in their volume, surface area and membrane curvature. The ratio between the surface area of the cytosolic and luminal leaflets (trans-membrane area asymmetry (TAA)) determines the membrane curvature within different sites of the organelle. Thus, the shape of the organelle could be critically dependent on TAA. Here, using mathematical modeling and stereological measurements of TAA during fast transformation of organelle shapes, we present evidence that suggests that when organelle volume and surface area are constant, TAA can regulate transformation of the shape of the Golgi apparatus, endosomal multivesicular bodies, and microvilli of brush borders of kidney epithelial cells. Extraction of membrane curvature by small spheres, such as COPI-dependent vesicles within the Golgi (extraction of positive curvature), or by intraluminal vesicles within endosomes (extraction of negative curvature) controls the shape of these organelles. For instance, Golgi tubulation is critically dependent on the fusion of COPI vesicles with Golgi cisternae, and vice versa, for the extraction of membrane curvature into 50–60 nm vesicles, to induce transformation of Golgi tubules into cisternae. Also, formation of intraluminal ultra-small vesicles after fusion of endosomes allows equilibration of their TAA, volume and surface area. Finally, when microvilli of the brush border are broken into vesicles and microvilli fragments, TAA of these membranes remains the same as TAA of the microvilli. Thus, TAA has a significant role in transformation of organelle shape when other factors remain constant. PMID:25761238

Dosimetric performance of the new high-definition multileaf collimator for intracranial stereotactic radiosurgery.

PubMed

Dhabaan, Anees; Elder, Eric; Schreibmann, Eduard; Crocker, Ian; Curran, Walter J; Oyesiku, Nelson M; Shu, Hui-Kuo; Fox, Tim

2010-06-21

The objective was to evaluate the performance of a high-definition multileaf collimator (MLC) of 2.5 mm leaf width (MLC2.5) and compare to standard 5 mm leaf width MLC (MLC5) for the treatment of intracranial lesions using dynamic conformal arcs (DCA) technique with a dedicated radiosurgery linear accelerator. Simulated cases of spherical targets were created to study solely the effect of target volume size on the performance of the two MLC systems independent of target shape complexity. In addition, 43 patients previously treated for intracranial lesions in our institution were retrospectively planned using DCA technique with MLC2.5 and MLC5 systems. The gross tumor volume ranged from 0.07 to 40.57 cm3 with an average volume of 5.9 cm3. All treatment parameters were kept the same for both MLC-based plans. The plan evaluation was performed using figures of merits (FOM) for a rapid and objective assessment on the quality of the two treatment plans for MLC2.5 and MLC5. The prescription isodose surface was selected as the greatest isodose surface covering >or= 95% of the target volume and delivering 95% of the prescription dose to 99% of target volume. A Conformity Index (CI) and conformity distance index (CDI) were used to quantifying the dose conformity to a target volume. To assess normal tissue sparing, a normal tissue difference (NTD) was defined as the difference between the volume of normal tissue receiving a certain dose utilizing MLC5 and the volume receiving the same dose using MLC2.5. The CI and normal tissue sparing for the simulated spherical targets were better with the MLC2.5 as compared to MLC5. For the clinical patients, the CI and CDI results indicated that the MLC2.5 provides better treatment conformity than MLC5 even at large target volumes. The CI's range was 1.15 to 2.44 with a median of 1.59 for MLC2.5 compared to 1.60-2.85 with a median of 1.71 for MLC5. Improved normal tissue sparing was also observed for MLC2.5 over MLC5, with the NTD always positive, indicating improvement, and ranging from 0.1 to 8.3 for normal tissue receiving 50% (NTV50), 70% (NTV70) and 90% (NTV90) of the prescription dose. The MLC2.5 has a dosimetric advantage over the MLC5 in Linac-based radiosurgery using DCA method for intracranial lesions, both in treatment conformity and normal tissue sparing when target shape complexity increases.

Analysis of radiation exposure for naval units of Operation Crossroads. Volume 2. (Appendix A) target ships. Technical report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weitz, R.; Thomas, C.; Klemm, J.

1982-03-03

External radiation doses are reconstructed for crews of support and target ships of Joint Task Force One at Operation CROSSROADS, 1946. Volume I describes the reconstruction methodology, which consists of modeling the radiation environment, to include the radioactivity of lagoon water, target ships, and support ship contamination; retracing ship paths through this environment; and calculating the doses to shipboard personnel. The USS RECLAIMER, a support ship, is selected as a representative ship to demonstrate this methodology. Doses for all other ships are summarized. Volume II (Appendix A) details the results for target ship personnel. Volume III (Appendix B) details themore » results for support ship personnel. Calculated doses for more than 36,000 personnel aboard support ships while at Bikini range from zero to 1.7 rem. Of those, approximately 34,000 are less than 0.5 rem. From the models provided, doses due to target ship reboarding and doses accrued after departure from Bikini can be calculated, based on the individual circumstances of exposure.« less

Pretreatment Predictors of Adverse Radiation Effects After Radiosurgery for Arteriovenous Malformation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hayhurst, Caroline; Monsalves, Eric; Prooijen, Monique van

Purpose: To identify vascular and dosimetric predictors of symptomatic T2 signal change and adverse radiation effects after radiosurgery for arteriovenous malformation, in order to define and validate preexisting risk models. Methods and Materials: A total of 125 patients with arteriovenous malformations (AVM) were treated at our institution between 2005 and 2009. Eighty-five patients have at least 12 months of clinical and radiological follow-up. Any new-onset headaches, new or worsening seizures, or neurological deficit were considered adverse events. Follow-up magnetic resonance images were assessed for new onset T2 signal change and the volume calculated. Pretreatment characteristics and dosimetric variables were analyzedmore » to identify predictors of adverse radiation effects. Results: There were 19 children and 66 adults in the study cohort, with a mean age of 34 (range 6-74). Twenty-three (27%) patients suffered adverse radiation effects (ARE), 9 patients with permanent neurological deficit (10.6%). Of these, 5 developed fixed visual field deficits. Target volume and 12 Gy volume were the most significant predictors of adverse radiation effects on univariate analysis (p < 0.001). Location and cortical eloquence were not significantly associated with the development of adverse events (p = 0.12). No additional vascular parameters were identified as predictive of ARE. There was a significant target volume threshold of 4 cm{sup 3}, above which the rate of ARE increased dramatically. Multivariate analysis target volume and the absence of prior hemorrhage are the only significant predictors of ARE. The volume of T2 signal change correlates to ARE, but only target volume is predictive of a higher volume of T2 signal change. Conclusions: Target volume and the absence of prior hemorrhage is the most accurate predictor of adverse radiation effects and complications after radiosurgery for AVMs. A high percentage of permanent visual field defects in this series suggest the optic radiation is a critical radiosensitive structure.« less

Syntheses of near-net-shaped monolithic hydroxyapatite and hydroxyapatite-ASTM F75 composites by the oxidation of solid metal-bearing precursors

NASA Astrophysics Data System (ADS)

Saw, Eaden

A novel powder-metallurgical route was used to fabricate near net-shaped hydroxyapatite, Ca10(PO4)6(OH)2 (HA) and HA+Co-C-Mo composite bodies. Ca and beta-Ca2P 2O7 with Ca/P ˜ 1.67 was intimately mixed by high-energy mechanical alloying, formed into desired shapes by pressing and machining, and then converted into HA with a series of heat treatments: a 600°C annealing in dry O2 completely oxidized calcium within 3 h, and a subsequent annealing at ≤1150°C in moist O2 yielded phase-pure HA. The reduction in solid volume associated with the oxidation of calcium (Vm[CaO] < Vm[Ca]) was offset by the increase in solid volume associated with the conversion of CaO and Ca2P2O7 into HA. Thus, the overall dimensional changes upon transformation of Ca+beta-Ca2P 2O7 precursors into HA can be relatively small. A mixture of Co-Cr-Mo powder with the precursor prepared from Ca and beta-Ca 2P2O7, targeted to yield a 75 to 25 volume ratio of Co-Cr-Mo to stoichiometric HA were prepared with the same method but different annealing cycles: annealing at 1150°C in de-oxygenized, flowing Ar resulted in partial densification of the composite bodies, and subsequent annealing at 850°C in a moist O2 atmosphere yielded a composite of Co-Cr-Mo alloy with phase-pure HA. The overall dimensional changes upon transformation of Ca+beta-Ca2P2O7+CO-Cr-Mo precursors into HA/Co-Cr-Mo composite were relatively small. In this thesis, the phase and microstructural evolution at various stages of transformation to monolithic HA and to HA/Co-Cr-Mo alloy composites are discussed. Planar reaction couples and powder compacts of CaO-TCP were prepared to study the kinetics for HA formation from CaO+TCP. Pt strips were used in the planar reaction couples as inert markers. These reaction couples were heated at 1150°C for various times in moist O2. The results of powder compact analyses fits Carter's model, which indicated that the rate of HA conversion from CaO and TCP is limited by solid state diffusion of Ca 2+ and/or OH- through the HA layer.

Evaluation of direct-exchange areas for a cylindrical enclosure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sika, J.

1991-11-01

This paper reports on a method for calculating the radiative heat transfer direct-exchange areas for surface-to-surface, volume-to-surface, and volume-to-volume pairs of zones in axisymmetric cylindrical geometries. With this method the calculation of the direct-exchange areas can be transformed from the original four-, five-, and sixfold integrals in the defining relations to just single and/or double integrals. Gray gas with absorption coefficient K is assumed.

fMRI evidence for sensorimotor transformations in human cortex during smooth pursuit eye movements.

PubMed

Kimmig, H; Ohlendorf, S; Speck, O; Sprenger, A; Rutschmann, R M; Haller, S; Greenlee, M W

2008-01-01

Smooth pursuit eye movements (SP) are driven by moving objects. The pursuit system processes the visual input signals and transforms this information into an oculomotor output signal. Despite the object's movement on the retina and the eyes' movement in the head, we are able to locate the object in space implying coordinate transformations from retinal to head and space coordinates. To test for the visual and oculomotor components of SP and the possible transformation sites, we investigated three experimental conditions: (I) fixation of a stationary target with a second target moving across the retina (visual), (II) pursuit of the moving target with the second target moving in phase (oculomotor), (III) pursuit of the moving target with the second target remaining stationary (visuo-oculomotor). Precise eye movement data were simultaneously measured with the fMRI data. Visual components of activation during SP were located in the motion-sensitive, temporo-parieto-occipital region MT+ and the right posterior parietal cortex (PPC). Motor components comprised more widespread activation in these regions and additional activations in the frontal and supplementary eye fields (FEF, SEF), the cingulate gyrus and precuneus. The combined visuo-oculomotor stimulus revealed additional activation in the putamen. Possible transformation sites were found in MT+ and PPC. The MT+ activation evoked by the motion of a single visual dot was very localized, while the activation of the same single dot motion driving the eye was rather extended across MT+. The eye movement information appeared to be dispersed across the visual map of MT+. This could be interpreted as a transfer of the one-dimensional eye movement information into the two-dimensional visual map. Potentially, the dispersed information could be used to remap MT+ to space coordinates rather than retinal coordinates and to provide the basis for a motor output control. A similar interpretation holds for our results in the PPC region.

Phase transformation dependence on initial plastic deformation mode in Si via nanoindentation

DOE PAGES

Wong, Sherman; Haberl, Bianca; Williams, James S.; ...

2016-09-30

Silicon in its diamond-cubic phase is known to phase transform to a technologically interesting mixture of the body-centred cubic and rhombohedral phases under nanoindentation pressure. In this study, we demonstrate that during plastic deformation the sample can traverse two distinct pathways, one that initially nucleates a phase transformation while the other initially nucleates crystalline defects. These two pathways remain distinct even after sufficient pressure is applied such that both deformation mechanisms are present within the sample. Here, it is further shown that the indents that initially nucleate a phase transformation generate larger, more uniform volumes of the phase transformed materialmore » than indents that initially nucleate crystalline defects.« less

Radiotherapy treatment planning: benefits of CT-MR image registration and fusion in tumor volume delineation.

PubMed

Djan, Igor; Petrović, Borislava; Erak, Marko; Nikolić, Ivan; Lucić, Silvija

2013-08-01

Development of imaging techniques, computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET), made great impact on radiotherapy treatment planning by improving the localization of target volumes. Improved localization allows better local control of tumor volumes, but also minimizes geographical misses. Mutual information is obtained by registration and fusion of images achieved manually or automatically. The aim of this study was to validate the CT-MRI image fusion method and compare delineation obtained by CT versus CT-MRI image fusion. The image fusion software (XIO CMS 4.50.0) was applied to delineate 16 patients. The patients were scanned on CT and MRI in the treatment position within an immobilization device before the initial treatment. The gross tumor volume (GTV) and clinical target volume (CTV) were delineated on CT alone and on CT+MRI images consecutively and image fusion was obtained. Image fusion showed that CTV delineated on a CT image study set is mainly inadequate for treatment planning, in comparison with CTV delineated on CT-MRI fused image study set. Fusion of different modalities enables the most accurate target volume delineation. This study shows that registration and image fusion allows precise target localization in terms of GTV and CTV and local disease control.

Size effects in martensitic microstructures: Finite-strain phase field model versus sharp-interface approach

NASA Astrophysics Data System (ADS)

Tůma, K.; Stupkiewicz, S.; Petryk, H.

2016-10-01

A finite-strain phase field model for martensitic phase transformation and twinning in shape memory alloys is developed and confronted with the corresponding sharp-interface approach extended to interfacial energy effects. The model is set in the energy framework so that the kinetic equations and conditions of mechanical equilibrium are fully defined by specifying the free energy and dissipation potentials. The free energy density involves the bulk and interfacial energy contributions, the latter describing the energy of diffuse interfaces in a manner typical for phase-field approaches. To ensure volume preservation during martensite reorientation at finite deformation within a diffuse interface, it is proposed to apply linear mixing of the logarithmic transformation strains. The physically different nature of phase interfaces and twin boundaries in the martensitic phase is reflected by introducing two order-parameters in a hierarchical manner, one as the reference volume fraction of austenite, and thus of the whole martensite, and the second as the volume fraction of one variant of martensite in the martensitic phase only. The microstructure evolution problem is given a variational formulation in terms of incremental fields of displacement and order parameters, with unilateral constraints on volume fractions explicitly enforced by applying the augmented Lagrangian method. As an application, size-dependent microstructures with diffuse interfaces are calculated for the cubic-to-orthorhombic transformation in a CuAlNi shape memory alloy and compared with the sharp-interface microstructures with interfacial energy effects.

Triggering conditions and mobility of debris flows associated to complex earthflows

NASA Astrophysics Data System (ADS)

Malet, J.-P.; Laigle, D.; Remaître, A.; Maquaire, O.

2005-03-01

Landslides on black marl slopes of the French Alps are, in most cases, complex catastrophic failures in which the initial structural slides transform into slow-moving earthflows. Under specific hydrological conditions, these earthflows can transform into debris flows. Due to their sediment volume and their high mobility, debris flow induced by landslides are far much dangerous than these resulting from continuous erosive processes. A fundamental point to correctly delineate the area exposed to debris flows on the alluvial fans is therefore to understand why and how some earthflows transform into debris flow while most of them stabilize. In this paper, a case of transformation from earthflow to debris flow is presented and analysed. An approach combining geomorphology, hydrology, geotechnics and rheology is adopted to model the debris flow initiation (failure stage) and its runout (postfailure stage). Using the Super-Sauze earthflow (Alpes-de-Haute-Provence, France) as a case study, the objective is to characterize the hydrological and mechanical conditions leading to debris flow initiation in such cohesive material. Results show a very good agreement between the observed runout distances and these calculated using the debris flow modeling code Cemagref 1-D. The deposit thickness in the depositional area and the velocities of the debris flows are also well reproduced. Furthermore, a dynamic slope stability analysis shows that conditions in the debris source area under average pore water pressures and moisture contents are close to failure. A small excess of water can therefore initiate failure. Seepage analysis is used to estimate the volume of debris that can be released for several hydroclimatic conditions. The failed volumes are then introduced in the Cemagref 1-D runout code to propose debris flow hazard scenarios. Results show that clayey earthflow can transform under 5-year return period rainfall conditions into 1-km runout debris flow of volumes ranging between 2000 to 5000 m 3. Slope failures induced by 25-year return period rainfall can trigger large debris flow events (30,000 to 50,000 m 3) that can reach the alluvial fan and cause damage.

Transformations of Supercooled Austenite in a Promising High-Strength Steel Grade Under Continuous Cooling Conditions

NASA Astrophysics Data System (ADS)

Maisuradze, M. V.; Ryzhkov, M. A.; Yudin, Yu. V.; Kuklina, A. A.

2017-11-01

Special features of the transformations of supercooled austenite occurring under continuous cooling of a promising high-strength steel grade not standardized in the Russian Federation are determined. A method for evaluating the volume fractions of structure constituents formed in the steel as a result of cooling from 925°C at various constant rates within 0.025 - 75 K/sec is proposed and tested. The results are generalized in the form of a thermokinetic diagram of transformations of supercooled austenite.

Static harmonization of dynamically harmonized Fourier transform ion cyclotron resonance cell.

PubMed

Zhdanova, Ekaterina; Kostyukevich, Yury; Nikolaev, Eugene

2017-08-01

Static harmonization in the Fourier transform ion cyclotron resonance cell improves the resolving power of the cell and prevents dephasing of the ion cloud in the case of any trajectory of the charged particle, not necessarily axisymmetric cyclotron (as opposed to dynamic harmonization). We reveal that the Fourier transform ion cyclotron resonance cell with dynamic harmonization (paracell) is proved to be statically harmonized. The volume of the statically harmonized potential distribution increases with an increase in the number of trap segments.

Amplicon based RNA interference targeting V2 gene of cotton leaf curl Kokhran virus-Burewala strain can provide resistance in transgenic cotton plants

USDA-ARS?s Scientific Manuscript database

An RNAi based gene construct designated “C2” was used to target the V2 region of the cotton leaf curl virus (CLCuV) genome which is responsible for virus movement. The construct was transformed into two elite cotton varieties MNH-786 and VH-289. A shoot apex method of plant transformation using Agr...

Artifacts in Radar Imaging of Moving Targets

DTIC Science & Technology

2012-09-01

CA, USA, 2007. [11] B. Borden, Radar imaging of airborne targets: A primer for Applied mathematicians and Physicists . New York, NY: Taylor and... Project (0704–0188) Washington DC 20503. 1. AGENCY USE ONLY (Leave blank) 2. REPORT DATE 21 September 2012 3. REPORT TYPE AND DATES COVERED...CW Continuous Wave DAC Digital to Analog Convertor DFT Discrete Fourier Transform FBP Filtered Back Projection FFT Fast Fourier Transform GPS

A hidden variable in shear transformation zone volume versus Poisson's ratio relation in metallic glasses

NASA Astrophysics Data System (ADS)

Kim, S. Y.; Oh, H. S.; Park, E. S.

2017-10-01

Herein, we elucidate a hidden variable in a shear transformation zone (STZ) volume (Ω) versus Poisson's ratio (ν) relation and clarify the correlation between STZ characteristics and the plasticity of metallic glasses (MGs). On the basis of cooperative shear model and atomic stress theories, we carefully formulate Ω as a function of molar volume (Vm) and ν. The twofold trend in Ω and ν is attributed to a relatively large variation of Vm as compared to that of ν as well as an inverse relation between Vm and ν. Indeed, the derived equation reveals that the number of atoms in an STZ instead of Ω is a microstructural characteristic which has a close relationship with plasticity since it reflects the preference of atomistic behaviors between cooperative shearing and the generation of volume strain fluctuation under stress. The results would deepen our understanding of the correlation between microscopic behaviors (STZ activation) and macroscopic properties (plasticity) in MGs and enable a quantitative approach in associating various STZ-related macroscopic behaviors with intrinsic properties of MGs.

Assessment of the Derivative-Moment Transformation method for unsteady-load estimation

NASA Astrophysics Data System (ADS)

Mohebbian, Ali; Rival, David

2011-11-01

It is often difficult, if not impossible, to measure the aerodynamic or hydrodynamic forces on a moving body. For this reason, a classical control-volume technique is typically applied to extract the unsteady forces instead. However, measuring the acceleration term within the volume of interest using PIV can be limited by optical access, reflections as well as shadows. Therefore in this study an alternative approach, termed the Derivative-Moment Transformation (DMT) method, is introduced and tested on a synthetic data set produced using numerical simulations. The test case involves the unsteady loading of a flat plate in a two-dimensional, laminar periodic gust. The results suggest that the DMT method can accurately predict the acceleration term so long as appropriate spatial and temporal resolutions are maintained. The major deficiency was found to be the determination of pressure in the wake. The effect of control-volume size was investigated suggesting that smaller domains work best by minimizing the associated error with the pressure field. When increasing the control-volume size, the number of calculations necessary for the pressure-gradient integration increases, in turn substantially increasing the error propagation.

Transforming Public Education: Cases in Education Entrepreneurship. Instructor's Guide

ERIC Educational Resources Information Center

Childress, Stacey M., Ed.

2010-01-01

This instructor's guide is intended for use with "Transforming Public Education: Cases in Education Entrepreneurship." This volume includes a teaching note for each case in the student edition; the note provides basic guidance in how to initaite and organize the flow of the case discussion as well as how the case links to others before…

Generation of strongly coupled plasmas by high power excimer laser

NASA Astrophysics Data System (ADS)

Zhu, Yongxiang; Liu, Jingru; Zhang, Yongsheng; Hu, Yun; Zhang, Jiyan; Zheng, Zhijian; Ye, Xisheng

2013-05-01

(ultraviolet). To generate strongly coupled plasmas (SCP) by high power excimer laser, an Au-CH-Al-CH target is used to make the Al sample reach the state of SCP, in which the Au layer transforms laser energy to X-ray that heating the sample by volume and the CH layers provides necessary constraints. With aid of the MULTI-1D code, we calculate the state of the Al sample and its relationship with peak intensity, width and wavelength of laser pulses. The calculated results suggest that an excimer laser with peak intensity of the magnitude of 1013W/cm2 and pulse width being 5ns - 10ns is suitable to generate SCP with the temperature being tens of eV and the density of electron being of the order of 1022/cm-3. Lasers with shorter wavelength, such as KrF laser, are preferable.

Solution of the weighted symmetric similarity transformations based on quaternions

NASA Astrophysics Data System (ADS)

Mercan, H.; Akyilmaz, O.; Aydin, C.

2017-12-01

A new method through Gauss-Helmert model of adjustment is presented for the solution of the similarity transformations, either 3D or 2D, in the frame of errors-in-variables (EIV) model. EIV model assumes that all the variables in the mathematical model are contaminated by random errors. Total least squares estimation technique may be used to solve the EIV model. Accounting for the heteroscedastic uncertainty both in the target and the source coordinates, that is the more common and general case in practice, leads to a more realistic estimation of the transformation parameters. The presented algorithm can handle the heteroscedastic transformation problems, i.e., positions of the both target and the source points may have full covariance matrices. Therefore, there is no limitation such as the isotropic or the homogenous accuracy for the reference point coordinates. The developed algorithm takes the advantage of the quaternion definition which uniquely represents a 3D rotation matrix. The transformation parameters: scale, translations, and the quaternion (so that the rotation matrix) along with their covariances, are iteratively estimated with rapid convergence. Moreover, prior least squares (LS) estimation of the unknown transformation parameters is not required to start the iterations. We also show that the developed method can also be used to estimate the 2D similarity transformation parameters by simply treating the problem as a 3D transformation problem with zero (0) values assigned for the z-components of both target and source points. The efficiency of the new algorithm is presented with the numerical examples and comparisons with the results of the previous studies which use the same data set. Simulation experiments for the evaluation and comparison of the proposed and the conventional weighted LS (WLS) method is also presented.

A Theileria parva Isolate of Low Virulence Infects a Subpopulation of Lymphocytes

PubMed Central

Geysen, Dirk; Goddeeris, Bruno M.; Awino, Elias; Dobbelaere, Dirk A. E.; Naessens, Jan

2012-01-01

Theileria parva is a tick-transmitted protozoan parasite that infects and transforms bovine lymphocytes. We have previously shown that Theileria parva Chitongo is an isolate with a lower virulence than that of T. parva Muguga. Lower virulence appeared to be correlated with a delayed onset of the logarithmic growth phase of T. parva Chitongo-transformed peripheral blood mononuclear cells after in vitro infection. In the current study, infection experiments with WC1+ γδ T cells revealed that only T. parva Muguga could infect these cells and that no transformed cells could be obtained with T. parva Chitongo sporozoites. Subsequent analysis of the susceptibility of different cell lines and purified populations of lymphocytes to infection and transformation by both isolates showed that T. parva Muguga sporozoites could attach to and infect CD4+, CD8+, and WC1+ T lymphocytes, but T. parva Chitongo sporozoites were observed to bind only to the CD8+ T cell population. Flow cytometry analysis of established, transformed clones confirmed this bias in target cells. T. parva Muguga-transformed clones consisted of different cell surface phenotypes, suggesting that they were derived from either host CD4+, CD8+, or WC1+ T cells. In contrast, all in vitro and in vivo T. parva Chitongo-transformed clones expressed CD8 but not CD4 or WC1, suggesting that the T. parva Chitongo-transformed target cells were exclusively infected CD8+ lymphocytes. Thus, a role of cell tropism in virulence is likely. Since the adhesion molecule p67 is 100% identical between the two strains, a second, high-affinity adhesin that determines target cell specificity appears to exist. PMID:22202119

Image encryption with chaotic map and Arnold transform in the gyrator transform domains

NASA Astrophysics Data System (ADS)

Sang, Jun; Luo, Hongling; Zhao, Jun; Alam, Mohammad S.; Cai, Bin

2017-05-01

An image encryption method combing chaotic map and Arnold transform in the gyrator transform domains was proposed. Firstly, the original secret image is XOR-ed with a random binary sequence generated by a logistic map. Then, the gyrator transform is performed. Finally, the amplitude and phase of the gyrator transform are permutated by Arnold transform. The decryption procedure is the inverse operation of encryption. The secret keys used in the proposed method include the control parameter and the initial value of the logistic map, the rotation angle of the gyrator transform, and the transform number of the Arnold transform. Therefore, the key space is large, while the key data volume is small. The numerical simulation was conducted to demonstrate the effectiveness of the proposed method and the security analysis was performed in terms of the histogram of the encrypted image, the sensitiveness to the secret keys, decryption upon ciphertext loss, and resistance to the chosen-plaintext attack.

Optical design of an in vivo laparoscopic lighting system

NASA Astrophysics Data System (ADS)

Liu, Xiaolong; Abdolmalaki, Reza Yazdanpanah; Mancini, Gregory J.; Tan, Jindong

2017-12-01

This paper proposes an in vivo laparoscopic lighting system design to address the illumination issues, namely poor lighting uniformity and low optical efficiency, existing in the state-of-the-art in vivo laparoscopic cameras. The transformable design of the laparoscopic lighting system is capable of carrying purposefully designed freeform optical lenses for achieving lighting performance with high illuminance uniformity and high optical efficiency in a desired target region. To design freeform optical lenses for extended light sources such as LEDs with Lambertian light intensity distributions, we present an effective and complete freeform optical design method. The procedures include (1) ray map computation by numerically solving a standard Monge-Ampere equation; (2) initial freeform optical surface construction by using Snell's law and a lens volume restriction; (3) correction of surface normal vectors due to accumulated errors from the initially constructed surfaces; and (4) feedback modification of the solution to deal with degraded illuminance uniformity caused by the extended sizes of the LEDs. We employed an optical design software package to evaluate the performance of our laparoscopic lighting system design. The simulation results show that our design achieves greater than 95% illuminance uniformity and greater than 89% optical efficiency (considering Fresnel losses) for illuminating the target surgical region.

Three-dimensional digital holographic aperture synthesis for rapid and highly-accurate large-volume metrology

NASA Astrophysics Data System (ADS)

Crouch, Stephen; Kaylor, Brant M.; Barber, Zeb W.; Reibel, Randy R.

2015-09-01

Currently large volume, high accuracy three-dimensional (3D) metrology is dominated by laser trackers, which typically utilize a laser scanner and cooperative reflector to estimate points on a given surface. The dependency upon the placement of cooperative targets dramatically inhibits the speed at which metrology can be conducted. To increase speed, laser scanners or structured illumination systems can be used directly on the surface of interest. Both approaches are restricted in their axial and lateral resolution at longer stand-off distances due to the diffraction limit of the optics used. Holographic aperture ladar (HAL) and synthetic aperture ladar (SAL) can enhance the lateral resolution of an imaging system by synthesizing much larger apertures by digitally combining measurements from multiple smaller apertures. Both of these approaches only produce two-dimensional imagery and are therefore not suitable for large volume 3D metrology. We combined the SAL and HAL approaches to create a swept frequency digital holographic 3D imaging system that provides rapid measurement speed for surface coverage with unprecedented axial and lateral resolution at longer standoff ranges. The technique yields a "data cube" of Fourier domain data, which can be processed with a 3D Fourier transform to reveal a 3D estimate of the surface. In this paper, we provide the theoretical background for the technique and show experimental results based on an ultra-wideband frequency modulated continuous wave (FMCW) chirped heterodyne ranging system showing ~100 micron lateral and axial precisions at >2 m standoff distances.

Transformation kinetics for the shock wave induced phase transition in cadmium sulfide crystals

NASA Astrophysics Data System (ADS)

Knudson, M. D.; Gupta, Y. M.

2002-06-01

Initial stage kinetics of the cadmium sulfide (CdS) phase transition was investigated using picosecond time-resolved electronic spectroscopy in plate-impact shock wave experiments. Real-time changes in the electronic spectra were observed, with 100 ps time resolution, in CdS single crystals shocked along a and c axes to stresses ranging between 35 and 90 kbar, which is above the phase-transition threshold stress of approximately 30 kbar. Significant difference in the transformation kinetics was observed for the two crystal orientations. At sufficiently high instantaneous stress, above approximately 60 to 70 kbar for a axis and 50 kbar for c axis, transformation to a metastable state appears to reach a constant state within the 100 ps time resolution. At lower instantaneous stresses, an incubation period on the order of several nanoseconds is observed prior to the onset of electronic changes that mark the onset of the structural change. The subsequent increase in absorbance was quite rapid, with a constant state being reached within the first few nanoseconds after the onset of the structural changes. These results suggest that the nucleation process determines the transformation rate. This insight into transformation kinetics, along with the transformation mechanism obtained from the high-stress experiments, was used to develop a phenomenological model, incorporating ideas of nucleation and growth in martensitic transformations, to simulate the time-dependent extinction of light observed in our experiments. The calculational results incorporating both extinction due to light absorption by the daughter phase volumes and scattering of light by small volumes of the daughter phase were in good agreement with experimental observations. Finally, the orientational differences observed in the transformation kinetics were interpreted in terms of the differences in the elastic-plastic response for the two orientations.

Feasibility and Initial Dosimetric Findings for a Randomized Trial Using Dose-Painted Multiparametric Magnetic Resonance Imaging–Defined Targets in Prostate Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bossart, Elizabeth L., E-mail: EBossart@med.miami.edu; Stoyanova, Radka; Sandler, Kiri

2016-06-01

Purpose: To compare dosimetric characteristics with multiparametric magnetic resonance imaging–identified imaging tumor volume (gross tumor volume, GTV), prostate clinical target volume and planning target volume, and organs at risk (OARs) for 2 treatment techniques representing 2 arms of an institutional phase 3 randomized trial of hypofractionated external beam image guided highly targeted radiation therapy. Methods and Materials: Group 1 (n=20) patients were treated before the trial inception with the standard dose prescription. Each patient had an additional treatment plan generated per the experimental arm. A total of 40 treatment plans were compared (20 plans for each technique). Group 2 (n=15)more » consists of patients currently accrued to the hypofractionated external beam image guided highly targeted radiation therapy trial. Plans were created as per the treatment arm, with additional plans for 5 of the group 2 experimental arm with a 3-mm expansion in the imaging GTV. Results: For all plans in both patient groups, planning target volume coverage ranged from 95% to 100%; GTV coverage of 89.3 Gy for the experimental treatment plans ranged from 95.2% to 99.8%. For both groups 1 and 2, the percent volumes of rectum/anus and bladder receiving 40 Gy, 65 Gy, and 80 Gy were smaller in the experimental plans than in the standard plans. The percent volume at 1 Gy per fraction and 1.625 Gy per fraction were compared between the standard and the experimental arms, and these were found to be equivalent. Conclusions: The dose per fraction to the OARs can be made equal even when giving a large simultaneous integrated boost to the GTV. The data suggest that a GTV margin may be added without significant dose effects on the OARs.« less

Perturbation of nucleo-cytoplasmic transport affects size of nucleus and nucleolus in human cells.

PubMed

Ganguly, Abira; Bhattacharjee, Chumki; Bhave, Madhura; Kailaje, Vaishali; Jain, Bhawik K; Sengupta, Isha; Rangarajan, Annapoorni; Bhattacharyya, Dibyendu

2016-03-01

Size regulation of human cell nucleus and nucleolus are poorly understood subjects. 3D reconstruction of live image shows that the karyoplasmic ratio (KR) increases by 30-80% in transformed cell lines compared to their immortalized counterpart. The attenuation of nucleo-cytoplasmic transport causes the KR value to increase by 30-50% in immortalized cell lines. Nucleolus volumes are significantly increased in transformed cell lines and the attenuation of nucleo-cytoplasmic transport causes a significant increase in the nucleolus volume of immortalized cell lines. A cytosol and nuclear fraction swapping experiment emphasizes the potential role of unknown cytosolic factors in nuclear and nucleolar size regulation. © 2016 Federation of European Biochemical Societies.

Comparison of plan quality and delivery time between volumetric arc therapy (RapidArc) and Gamma Knife radiosurgery for multiple cranial metastases.

PubMed

Thomas, Evan M; Popple, Richard A; Wu, Xingen; Clark, Grant M; Markert, James M; Guthrie, Barton L; Yuan, Yu; Dobelbower, Michael C; Spencer, Sharon A; Fiveash, John B

2014-10-01

Volumetric modulated arc therapy (VMAT) has been shown to be feasible for radiosurgical treatment of multiple cranial lesions with a single isocenter. To investigate whether equivalent radiosurgical plan quality and reduced delivery time could be achieved in VMAT for patients with multiple intracranial targets previously treated with Gamma Knife (GK) radiosurgery. We identified 28 GK treatments of multiple metastases. These were replanned for multiarc and single-arc, single-isocenter VMAT (RapidArc) in Eclipse. The prescription for all targets was standardized to 18 Gy. Each plan was normalized for 100% prescription dose to 99% to 100% of target volume. Plan quality was analyzed by target conformity (Radiation Therapy Oncology Group and Paddick conformity indices [CIs]), dose falloff (area under the dose-volume histogram curve), as well as the V4.5, V9, V12, and V18 isodose volumes. Other end points included beam-on and treatment time. Compared with GK, multiarc VMAT improved median plan conformity (CIVMAT = 1.14, CIGK = 1.65; P < .001) with no significant difference in median dose falloff (P = .269), 12 Gy isodose volume (P = .500), or low isodose spill (P = .49). Multiarc VMAT plans were associated with markedly reduced treatment time. A predictive model of the 12 Gy isodose volume as a function of tumor number and volume was also developed. For multiple target stereotactic radiosurgery, 4-arc VMAT produced clinically equivalent conformity, dose falloff, 12 Gy isodose volume, and low isodose spill, and reduced treatment time compared with GK. Because of its similar plan quality and increased delivery efficiency, single-isocenter VMAT radiosurgery may constitute an attractive alternative to multi-isocenter radiosurgery for some patients.

Atlas-Based Segmentation Improves Consistency and Decreases Time Required for Contouring Postoperative Endometrial Cancer Nodal Volumes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Young, Amy V.; Department of Radiation Oncology, St. Luke's-Roosevelt Hospital, New York, NY; Wortham, Angela

2011-03-01

Purpose: Accurate target delineation of the nodal volumes is essential for three-dimensional conformal and intensity-modulated radiotherapy planning for endometrial cancer adjuvant therapy. We hypothesized that atlas-based segmentation ('autocontouring') would lead to time savings and more consistent contours among physicians. Methods and Materials: A reference anatomy atlas was constructed using the data from 15 postoperative endometrial cancer patients by contouring the pelvic nodal clinical target volume on the simulation computed tomography scan according to the Radiation Therapy Oncology Group 0418 trial using commercially available software. On the simulation computed tomography scans from 10 additional endometrial cancer patients, the nodal clinical targetmore » volume autocontours were generated. Three radiation oncologists corrected the autocontours and delineated the manual nodal contours under timed conditions while unaware of the other contours. The time difference was determined, and the overlap of the contours was calculated using Dice's coefficient. Results: For all physicians, manual contouring of the pelvic nodal target volumes and editing the autocontours required a mean {+-} standard deviation of 32 {+-} 9 vs. 23 {+-} 7 minutes, respectively (p = .000001), a 26% time savings. For each physician, the time required to delineate the manual contours vs. correcting the autocontours was 30 {+-} 3 vs. 21 {+-} 5 min (p = .003), 39 {+-} 12 vs. 30 {+-} 5 min (p = .055), and 29 {+-} 5 vs. 20 {+-} 5 min (p = .0002). The mean overlap increased from manual contouring (0.77) to correcting the autocontours (0.79; p = .038). Conclusion: The results of our study have shown that autocontouring leads to increased consistency and time savings when contouring the nodal target volumes for adjuvant treatment of endometrial cancer, although the autocontours still required careful editing to ensure that the lymph nodes at risk of recurrence are properly included in the target volume.« less

Coverage-based constraints for IMRT optimization

NASA Astrophysics Data System (ADS)

Mescher, H.; Ulrich, S.; Bangert, M.

2017-09-01

Radiation therapy treatment planning requires an incorporation of uncertainties in order to guarantee an adequate irradiation of the tumor volumes. In current clinical practice, uncertainties are accounted for implicitly with an expansion of the target volume according to generic margin recipes. Alternatively, it is possible to account for uncertainties by explicit minimization of objectives that describe worst-case treatment scenarios, the expectation value of the treatment or the coverage probability of the target volumes during treatment planning. In this note we show that approaches relying on objectives to induce a specific coverage of the clinical target volumes are inevitably sensitive to variation of the relative weighting of the objectives. To address this issue, we introduce coverage-based constraints for intensity-modulated radiation therapy (IMRT) treatment planning. Our implementation follows the concept of coverage-optimized planning that considers explicit error scenarios to calculate and optimize patient-specific probabilities q(\\hat{d}, \\hat{v}) of covering a specific target volume fraction \\hat{v} with a certain dose \\hat{d} . Using a constraint-based reformulation of coverage-based objectives we eliminate the trade-off between coverage and competing objectives during treatment planning. In-depth convergence tests including 324 treatment plan optimizations demonstrate the reliability of coverage-based constraints for varying levels of probability, dose and volume. General clinical applicability of coverage-based constraints is demonstrated for two cases. A sensitivity analysis regarding penalty variations within this planing study based on IMRT treatment planning using (1) coverage-based constraints, (2) coverage-based objectives, (3) probabilistic optimization, (4) robust optimization and (5) conventional margins illustrates the potential benefit of coverage-based constraints that do not require tedious adjustment of target volume objectives.

Geminivirus-Mediated Genome Editing in Potato (Solanum tuberosum L.) Using Sequence-Specific Nucleases

PubMed Central

Butler, Nathaniel M.; Baltes, Nicholas J.; Voytas, Daniel F.; Douches, David S.

2016-01-01

Genome editing using sequence-specific nucleases (SSNs) is rapidly being developed for genetic engineering in crop species. The utilization of zinc finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), and clustered regularly interspaced short palindromic repeats/CRISPR-associated systems (CRISPR/Cas) for inducing double-strand breaks facilitates targeting of virtually any sequence for modification. Targeted mutagenesis via non-homologous end-joining (NHEJ) has been demonstrated extensively as being the preferred DNA repair pathway in plants. However, gene targeting via homologous recombination (HR) remains more elusive but could be a powerful tool for directed DNA repair. To overcome barriers associated with gene targeting, a geminivirus replicon (GVR) was used to deliver SSNs targeting the potato ACETOLACTATE SYNTHASE1 (ALS1) gene and repair templates designed to incorporate herbicide-inhibiting point mutations within the ALS1 locus. Transformed events modified with GVRs held point mutations that were capable of supporting a reduced herbicide susceptibility phenotype, while events transformed with conventional T-DNAs held no detectable mutations and were similar to wild-type. Regeneration of transformed events improved detection of point mutations that supported a stronger reduced herbicide susceptibility phenotype. These results demonstrate the use of geminiviruses for delivering genome editing reagents in plant species, and a novel approach to gene targeting in a vegetatively propagated species. PMID:27493650

Facies Modeling Using 3D Pre-Stack Simultaneous Seismic Inversion and Multi-Attribute Probability Neural Network Transform in the Wattenberg Field, Colorado

NASA Astrophysics Data System (ADS)

Harryandi, Sheila

The Niobrara/Codell unconventional tight reservoir play at Wattenberg Field, Colorado has potentially two billion barrels of oil equivalent requiring hundreds of wells to access this resource. The Reservoir Characterization Project (RCP), in conjunction with Anadarko Petroleum Corporation (APC), began reservoir characterization research to determine how to increase reservoir recovery while maximizing operational efficiency. Past research results indicate that targeting the highest rock quality within the reservoir section for hydraulic fracturing is optimal for improving horizontal well stimulation through multi-stage hydraulic fracturing. The reservoir is highly heterogeneous, consisting of alternating chalks and marls. Modeling the facies within the reservoir is very important to be able to capture the heterogeneity at the well-bore scale; this heterogeneity is then upscaled from the borehole scale to the seismic scale to distribute the heterogeneity in the inter-well space. I performed facies clustering analysis to create several facies defining the reservoir interval in the RCP Wattenberg Field study area. Each facies can be expressed in terms of a range of rock property values from wells obtained by cluster analysis. I used the facies classification from the wells to guide the pre-stack seismic inversion and multi-attribute transform. The seismic data extended the facies information and rock quality information from the wells. By obtaining this information from the 3D facies model, I generated a facies volume capturing the reservoir heterogeneity throughout a ten square mile study-area within the field area. Recommendations are made based on the facies modeling, which include the location for future hydraulic fracturing/re-fracturing treatments to improve recovery from the reservoir, and potential deeper intervals for future exploration drilling targets.

Standardizing Naming Conventions in Radiation Oncology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Santanam, Lakshmi; Hurkmans, Coen; Mutic, Sasa

2012-07-15

Purpose: The aim of this study was to report on the development of a standardized target and organ-at-risk naming convention for use in radiation therapy and to present the nomenclature for structure naming for interinstitutional data sharing, clinical trial repositories, integrated multi-institutional collaborative databases, and quality control centers. This taxonomy should also enable improved plan benchmarking between clinical institutions and vendors and facilitation of automated treatment plan quality control. Materials and Methods: The Advanced Technology Consortium, Washington University in St. Louis, Radiation Therapy Oncology Group, Dutch Radiation Oncology Society, and the Clinical Trials RT QA Harmonization Group collaborated in creatingmore » this new naming convention. The International Commission on Radiation Units and Measurements guidelines have been used to create standardized nomenclature for target volumes (clinical target volume, internal target volume, planning target volume, etc.), organs at risk, and planning organ-at-risk volumes in radiation therapy. The nomenclature also includes rules for specifying laterality and margins for various structures. The naming rules distinguish tumor and nodal planning target volumes, with correspondence to their respective tumor/nodal clinical target volumes. It also provides rules for basic structure naming, as well as an option for more detailed names. Names of nonstandard structures used mainly for plan optimization or evaluation (rings, islands of dose avoidance, islands where additional dose is needed [dose painting]) are identified separately. Results: In addition to its use in 16 ongoing Radiation Therapy Oncology Group advanced technology clinical trial protocols and several new European Organization for Research and Treatment of Cancer protocols, a pilot version of this naming convention has been evaluated using patient data sets with varying treatment sites. All structures in these data sets were satisfactorily identified using this nomenclature. Conclusions: Use of standardized naming conventions is important to facilitate comparison of dosimetry across patient datasets. The guidelines presented here will facilitate international acceptance across a wide range of efforts, including groups organizing clinical trials, Radiation Oncology Institute, Dutch Radiation Oncology Society, Integrating the Healthcare Enterprise, Radiation Oncology domain (IHE-RO), and Digital Imaging and Communication in Medicine (DICOM).« less

Optimization of Craniospinal Irradiation for Pediatric Medulloblastoma Using VMAT and IMRT.

PubMed

Al-Wassia, Rolina K; Ghassal, Noor M; Naga, Adly; Awad, Nesreen A; Bahadur, Yasir A; Constantinescu, Camelia

2015-10-01

Intensity-modulated radiotherapy (IMRT) and volumetric-modulated arc therapy (VMAT) provide highly conformal target radiation doses, but also expose large volumes of healthy tissue to low-dose radiation. With improving survival, more children with medulloblastoma (MB) are at risk of late adverse effects of radiotherapy, including secondary cancers. We evaluated the characteristics of IMRT and VMAT craniospinal irradiation treatment plans in children with standard-risk MB to compare radiation dose delivery to target organs and organs at risk (OAR). Each of 10 children with standard-risk MB underwent both IMRT and VMAT treatment planning. Dose calculations used inverse planning optimization with a craniospinal dose of 23.4 Gy followed by a posterior fossa boost to 55.8 Gy. Clinical and planning target volumes were demarcated on axial computed tomography images. Dose distributions to target organs and OAR for each planning technique were measured and compared with published dose-volume toxicity data for pediatric patients. All patients completed treatment planning for both techniques. Analyses and comparisons of dose distributions and dose-volume histograms for the planned target volumes, and dose delivery to the OAR for each technique demonstrated the following: (1) VMAT had a modest, but significantly better, planning target volume-dose coverage and homogeneity compared with IMRT; (2) there were different OAR dose-sparing profiles for IMRT versus VMAT; and (3) neither IMRT nor VMAT demonstrated dose reductions to the published pediatric dose limits for the eyes, the lens, the cochlea, the pituitary, and the brain. The use of both IMRT and VMAT provides good target tissue coverage and sparing of the adjacent tissue for MB. Both techniques resulted in OAR dose delivery within published pediatric dose guidelines, except those mentioned above. Pediatric patients with standard-risk MB remain at risk for late endocrinologic, sensory (auditory and visual), and brain functional impairments.

[Effect of image fusion technology of radioactive particles implantation before and after the planning target and dosimetry].

PubMed

Jiang, Y L; Yu, J P; Sun, H T; Guo, F X; Ji, Z; Fan, J H; Zhang, L J; Li, X; Wang, J J

2017-08-01

Objective: To compare the post-implant target volumes and dosimetric evaluation with pre-plan, the gross tumor volume(GTV) by CT image fusion-based and the manual delineation of target volume in CT guided radioactive seeds implantation. Methods: A total of 10 patients treated under CT-guidance (125)I seed implantation during March 2016 to April 2016 were analyzed in Peking University Third Hospital.All patients underwent pre-operative CT simulation, pre-operative planning, implantation seeds, CT scanning after seed implantation and dosimetric evaluation of GTV.In every patient, post-implant target volumes were delineated by both two methods, and were divided into two groups. Group 1: image fusion pre-implantation simulation and post-operative CT image, then the contours of GTV were automatically performed by brachytherapy treatment planning system; Group 2: the contouring of the GTV on post-operative CT image were performed manually by three senior radiation oncologists independently. The average of three data was sets. Statistical analyses were performed using SPSS software, version 3.2.0. The paired t -test was used to compare the target volumes and D(90) parameters in two modality. Results: In Group 1, average volume of GTV in post-operation group was 12-167(73±56) cm(3). D(90) was 101-153 (142±19)Gy. In Group 2, they were 14-186(80±58)cm(3) and 96-146(122±16) Gy respectively. In both target volumes and D(90), there was no statistical difference between pre-operation and post-operation in Group 1.The D(90) was slightly lower than that of pre-plan group, but there was no statistical difference ( P =0.142); in Group 2, between pre-operation and post-operation group, there was a significant statistical difference in the GTV ( P =0.002). The difference of D(90) was similarly ( P <0.01). Conclusion: The method of delineation of post-implant GTV through fusion pre-implantation simulation and post-operative CT scan images, the contours of GTV are automatically performed by brachytherapy treatment planning system appears to have improved more accuracy, reproducibility and convenience than manual delineation of target volume by maximum reduce the interference from artificial factor and metal artifacts. Further work and more cases are required in the future.

Extraction of membrane structure in eyeball from MR volumes

NASA Astrophysics Data System (ADS)

Oda, Masahiro; Kin, Taichi; Mori, Kensaku

2017-03-01

This paper presents an accurate extraction method of spherical shaped membrane structures in the eyeball from MR volumes. In ophthalmic surgery, operation field is limited to a small region. Patient specific surgical simulation is useful to reduce complications. Understanding of tissue structure in the eyeball of a patient is required to achieve patient specific surgical simulations. Previous extraction methods of tissue structure in the eyeball use optical coherence tomography (OCT) images. Although OCT images have high resolution, imaging regions are limited to very small. Global structure extraction of the eyeball is difficult from OCT images. We propose an extraction method of spherical shaped membrane structures including the sclerotic coat, choroid, and retina. This method is applied to a T2 weighted MR volume of the head region. MR volume can capture tissue structure of whole eyeball. Because we use MR volumes, out method extracts whole membrane structures in the eyeball. We roughly extract membrane structures by applying a sheet structure enhancement filter. The rough extraction result includes parts of the membrane structures. Then, we apply the Hough transform to extract a sphere structure from the voxels set of the rough extraction result. The Hough transform finds a sphere structure from the rough extraction result. An experimental result using a T2 weighted MR volume of the head region showed that the proposed method can extract spherical shaped membrane structures accurately.

DOE Office of Scientific and Technical Information (OSTI.GOV)

MacFadden, Derek; Zhang Beibei; Brock, Kristy K.

Purpose: Increasing the magnetic resonance imaging (MRI) field strength can improve image resolution and quality, but concerns remain regarding the influence on geometric fidelity. The objectives of the present study were to spatially investigate the effect of 3-Tesla (3T) MRI on clinical target localization for stereotactic radiosurgery. Methods and Materials: A total of 39 patients were enrolled in a research ethics board-approved prospective clinical trial. Imaging (1.5T and 3T MRI and computed tomography) was performed after stereotactic frame placement. Stereotactic target localization at 1.5T vs. 3T was retrospectively analyzed in a representative cohort of patients with tumor (n = 4)more » and functional (n = 5) radiosurgical targets. The spatial congruency of the tumor gross target volumes was determined by the mean discrepancy between the average gross target volume surfaces at 1.5T and 3T. Reproducibility was assessed by the displacement from an averaged surface and volume congruency. Spatial congruency and the reproducibility of functional radiosurgical targets was determined by comparing the mean and standard deviation of the isocenter coordinates. Results: Overall, the mean absolute discrepancy across all patients was 0.67 mm (95% confidence interval, 0.51-0.83), significantly <1 mm (p < .010). No differences were found in the overall interuser target volume congruence (mean, 84% for 1.5T vs. 84% for 3T, p > .4), and the gross target volume surface mean displacements were similar within and between users. The overall average isocenter coordinate discrepancy for the functional targets at 1.5T and 3T was 0.33 mm (95% confidence interval, 0.20-0.48), with no patient-specific differences between the mean values (p >.2) or standard deviations (p >.1). Conclusion: Our results have provided clinically relevant evidence supporting the spatial validity of 3T MRI for use in stereotactic radiosurgery under the imaging conditions used.« less

SU-E-T-480: Radiobiological Dose Comparison of Single Fraction SRS, Multi-Fraction SRT and Multi-Stage SRS of Large Target Volumes Using the Linear-Quadratic Formula

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ding, C; Hrycushko, B; Jiang, S

2014-06-01

Purpose: To compare the radiobiological effect on large tumors and surrounding normal tissues from single fraction SRS, multi-fractionated SRT, and multi-staged SRS treatment. Methods: An anthropomorphic head phantom with a centrally located large volume target (18.2 cm{sup 3}) was scanned using a 16 slice large bore CT simulator. Scans were imported to the Multiplan treatment planning system where a total prescription dose of 20Gy was used for a single, three staged and three fractionated treatment. Cyber Knife treatment plans were inversely optimized for the target volume to achieve at least 95% coverage of the prescription dose. For the multistage plan,more » the target was segmented into three subtargets having similar volume and shape. Staged plans for individual subtargets were generated based on a planning technique where the beam MUs of the original plan on the total target volume are changed by weighting the MUs based on projected beam lengths within each subtarget. Dose matrices for each plan were export in DICOM format and used to calculate equivalent dose distributions in 2Gy fractions using an alpha beta ratio of 10 for the target and 3 for normal tissue. Results: Singe fraction SRS, multi-stage plan and multi-fractionated SRT plans had an average 2Gy dose equivalent to the target of 62.89Gy, 37.91Gy and 33.68Gy, respectively. The normal tissue within 12Gy physical dose region had an average 2Gy dose equivalent of 29.55Gy, 16.08Gy and 13.93Gy, respectively. Conclusion: The single fraction SRS plan had the largest predicted biological effect for the target and the surrounding normal tissue. The multi-stage treatment provided for a more potent biologically effect on target compared to the multi-fraction SRT treatments with less biological normal tissue than single-fraction SRS treatment.« less

From Broadway to Berlin: Transformative Learning through German Hip-Hop

ERIC Educational Resources Information Center

Sosulski, Michael J.

2013-01-01

This article explores the possibilities for effecting Transformative Learning in students of German language and culture through the use of popular music videos, in both the target and the students' own languages. Transformative Learning, a term that has differing valences in numerous academic disciplines, is employed here in its social-scientific…

Transforming growth factor-β1 promotes breast cancer metastasis by downregulating miR-196a-3p expression.

PubMed

Chen, Yan; Huang, Shai; Wu, Bo; Fang, Jiankai; Zhu, Minsheng; Sun, Li; Zhang, Lifeng; Zhang, Yongsheng; Sun, Maomin; Guo, Lingling; Wang, Shouli

2017-07-25

Transforming growth factor-β1 is considered a key contributor to the progression of breast cancer. MicroRNAs are important factors in the development and progression of many malignancies. In the present study, upon studies of breast cancer cell lines and tissues, we showed that microRNA -196a-3p is decreased by transforming growth factor-β1 in breast cancer cells and associated with breast cancer progression. We identified neuropilin-2 as a target gene of microRNA -196a-3p and showed that it is regulated by transforming growth factor-β1. Moreover, transforming growth factor-β1-mediated inhibition of microRNA -196a-3p and activation of neuropilin-2were required for transforming growth factor-β1-induced migration and invasion of breast cancer cells. In addition, neuropilin-2 expression was suppressed in breast tumors, particularly in triple-negative breast cancers. Collectively, our findings strongly indicate that microRNA -196a-3p is a predictive biomarker of breast cancer metastasis and patient survival and a potential therapeutic target in metastatic breast cancer.

Altering the sex determination pathway in Drosophila fat body modifies sex-specific stress responses

PubMed Central

Neckameyer, Wendi S.

2014-01-01

The stress response in Drosophila melanogaster reveals sex differences in behavior, similar to what has been observed in mammals. However, unlike mammals, the sex determination pathway in Drosophila is well established, making this an ideal system to identify factors involved in the modulation of sex-specific responses to stress. In this study, we show that the Drosophila fat body, which has been shown to be important for energy homeostasis and sex determination, is a dynamic tissue that is altered in response to stress in a sex and time-dependent manner. We manipulated the sex determination pathway in the fat body via targeted expression of transformer and transformer-2 and analyzed these animals for changes in their response to stress. In the majority of cases, manipulation of transformer or transformer-2 was able to change the physiological output in response to starvation and oxidative stress to that of the opposite sex. Our data also uncover the possibility of additional downstream targets for transformer and transformer-2 that are separate from the sex determination pathway and can influence behavioral and physiological responses. PMID:24789992

Cereal transformation through particle bombardment

NASA Technical Reports Server (NTRS)

Casas, A. M.; Kononowicz, A. K.; Bressan, R. A.; Hasegawa, P. M.; Mitchell, C. A. (Principal Investigator)

1995-01-01

The review focuses on experiments that lead to stable transformation in cereals using microprojectile bombardment. The discussion of biological factors that affect transformation examines target tissues and vector systems for gene transfer. The vector systems include reporter genes, selectable markers, genes of agronomic interest, and vector constructions. Other topics include physical parameters that affect DNA delivery, selection of stably transformed cells and plant regeneration, and analysis of gene expression and transmission to the progeny.

SU-G-JeP3-09: Tumor Location Prediction Using Natural Respiratory Volume for Respiratory Gated Radiation Therapy (RGRT): System Verification Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, M; Jung, J; Yoon, D

Purpose: Respiratory gated radiation therapy (RGRT) gives accurate results when a patient’s breathing is stable and regular. Thus, the patient should be fully aware during respiratory pattern training before undergoing the RGRT treatment. In order to bypass the process of respiratory pattern training, we propose a target location prediction system for RGRT that uses only natural respiratory volume, and confirm its application. Methods: In order to verify the proposed target location prediction system, an in-house phantom set was used. This set involves a chest phantom including target, external markers, and motion generator. Natural respiratory volume signals were generated using themore » random function in MATLAB code. In the chest phantom, the target takes a linear motion based on the respiratory signal. After a four-dimensional computed tomography (4DCT) scan of the in-house phantom, the motion trajectory was derived as a linear equation. The accuracy of the linear equation was compared with that of the motion algorithm used by the operating motion generator. In addition, we attempted target location prediction using random respiratory volume values. Results: The correspondence rate of the linear equation derived from the 4DCT images with the motion algorithm of the motion generator was 99.41%. In addition, the average error rate of target location prediction was 1.23% for 26 cases. Conclusion: We confirmed the applicability of our proposed target location prediction system for RGRT using natural respiratory volume. If additional clinical studies can be conducted, a more accurate prediction system can be realized without requiring respiratory pattern training.« less

Transformers: Shape-Changing Space Systems Built with Robotic Textiles

NASA Technical Reports Server (NTRS)

Stoica, Adrian

2013-01-01

Prior approaches to transformer-like robots had only very limited success. They suffer from lack of reliability, ability to integrate large surfaces, and very modest change in overall shape. Robots can now be built from two-dimensional (2D) layers of robotic fabric. These transformers, a new kind of robotic space system, are dramatically different from current systems in at least two ways. First, the entire transformer is built from a single, thin sheet; a flexible layer of a robotic fabric (ro-fabric); or robotic textile (ro-textile). Second, the ro-textile layer is foldable to small volume and self-unfolding to adapt shape and function to mission phases.

Planning evaluation of radiotherapy for complex lung cancer cases using helical tomotherapy

NASA Astrophysics Data System (ADS)

Kron, Tomas; Grigorov, Grigor; Yu, Edward; Yartsev, Slav; Chen, Jeff Z.; Wong, Eugene; Rodrigues, George; Trenka, Kris; Coad, Terry; Bauman, Glenn; Van Dyk, Jake

2004-08-01

Lung cancer treatment is one of the most challenging fields in radiotherapy. The aim of the present study was to investigate what role helical tomotherapy (HT), a novel approach to the delivery of highly conformal dose distributions using intensity-modulated radiation fan beams, can play in difficult cases with large target volumes typical for many of these patients. Tomotherapy plans were developed for 15 patients with stage III inoperable non-small-cell lung cancer. While not necessarily clinically indicated, elective nodal irradiation was included for all cases to create the most challenging scenarios with large target volumes. A 2 cm margin was used around the gross tumour volume (GTV) to generate primary planning target volume (PTV2) and 1 cm margin around elective nodes for secondary planning target volume (PTV1) resulting in PTV1 volumes larger than 1000 cm3 in 13 of the 15 patients. Tomotherapy plans were created using an inverse treatment planning system (TomoTherapy Inc.) based on superposition/convolution dose calculation for a fan beam thickness of 25 mm and a pitch factor between 0.3 and 0.8. For comparison, plans were created using an intensity-modulated radiation therapy (IMRT) approach planned on a commercial treatment planning system (TheraplanPlus, Nucletron). Tomotherapy delivery times for the large target volumes were estimated to be between 4 and 19 min. Using a prescribed dose of 60 Gy to PTV2 and 46 Gy to PTV1, the mean lung dose was 23.8 ± 4.6 Gy. A 'dose quality factor' was introduced to correlate the plan outcome with patient specific parameters. A good correlation was found between the quality of the HT plans and the IMRT plans with HT being slightly better in most cases. The overlap between lung and PTV was found to be a good indicator of plan quality for HT. The mean lung dose was found to increase by approximately 0.9 Gy per percent overlap volume. Helical tomotherapy planning resulted in highly conformal dose distributions. It allowed easy achievement of two different dose levels in the target simultaneously. As the overlap between PTV and lung volume is a major predictor of mean lung dose, future work will be directed to control of margins. Work is underway to investigate the possibility of breath-hold techniques for tomotherapy delivery to facilitate this aim.

The State of Asian Pacific America: Transforming Race Relations. A Public Policy Report, Volume IV.

ERIC Educational Resources Information Center

Ong, Paul M., Ed.

The papers in this collection respond to the importance of race in U.S. society by providing a comprehensive, multidisciplinary empirical analysis of the diverse ways in which Asian Pacific Americans are redefining and transforming contemporary U.S. race relations. Following a preface by Don T. Nakanishi and J. D. Hokoyama, the chapters are: (1)…

Optimization of Focused Ultrasound and Image Based Modeling in Image Guided Interventions

NASA Astrophysics Data System (ADS)

Almekkawy, Mohamed Khaled Ibrahim

Image-guided high intensity focused ultrasound (HIFU) is becoming increasingly accepted as a form of noninvasive ablative therapy for the treatment of prostate cancer, uterine fibroids and other tissue abnormalities. In principle, HIFU beams can be focused within small volumes which results in forming precise lesions within the target volume (e.g. tumor, atherosclerotic plaque) while sparing the intervening tissue. With this precision, HIFU offers the promise of noninvasive tumor therapy. The goal of this thesis is to develop an image-guidance mode with an interactive image-based computational modeling of tissue response to HIFU. This model could be used in treatment planning and post-treatment retrospective evaluation of treatment outcome(s). Within the context of treatment planning, the challenge of using HIFU to target tumors in organs partially obscured by the rib cage are addressed. Ribs distort HIFU beams in a manner that reduces the focusing gain at the target (tumor) and could cause a treatment-limiting collateral damage. We present a refocusing algorithms to efficiently steer higher power towards the target while limiting power deposition on the ribs, improving the safety and efficacy of tumor ablation. Our approach is based on an approximation of a non-convex to a convex optimization known as the semidefinite relaxation (SDR) technique. An important advantage of the SDR method over previously proposed optimization methods is the explicit control of the sidelobes in the focal plane. A finite-difference time domain (FDTD) heterogeneous propagation model of a 1-MHz concave phased array was used to model the acoustic propagation and temperature simulations in different tissues including ribs. The numerical methods developed for the refocusing problem are also used for retrospective analysis of targeting of atherosclerotic plaques using HIFU. Cases were simulated where seven adjacent HIFU shots (5000 W/cm2, 2 sec exposure time) were focused at the plaque tissue within the posterior wall of external femoral artery. After segmentation of the ultrasound image obtained for the treatment region in-vivo, we integrated this anatomical information into our simulation to account for different parameters that may be caused by these multi-region anatomical complexities. An FDTD heterogeneous model was used for both acoustic field and temperature computations. The acoustic field simulation considered a concave (40-mm radius of curvature) 32-element array operating at 3.5 MHz. To account for the blood flow in the vicinity of the target (plaque), we have used a modified transient bioheat transfer equation (tBHTE) with a convective term. The results from the numerical simulation were in good agreement with the thermal lesions identified by histological examination of the treated tissues. Within the context of accounting for the blood flow in tBHTE, the estimation of the displacement of tissue and blood motion are addressed. A new multi-dimensional speckle tracking method (MDST) utilizing the Riesz transform with subsample accuracy in all dimensions is described. Field II simulation of flow data in a channel is generated to provide a validation of the accuracy of the method. In addition, the new MDST method is applied to imaging data from the carotid artery of a healthy human volunteers. The results obtained show that using Riesz transform produces more robust estimation of the true displacement compared to previously published results.

Configuration Analysis of the ERS Points in Large-Volume Metrology System

PubMed Central

Jin, Zhangjun; Yu, Cijun; Li, Jiangxiong; Ke, Yinglin

2015-01-01

In aircraft assembly, multiple laser trackers are used simultaneously to measure large-scale aircraft components. To combine the independent measurements, the transformation matrices between the laser trackers’ coordinate systems and the assembly coordinate system are calculated, by measuring the enhanced referring system (ERS) points. This article aims to understand the influence of the configuration of the ERS points that affect the transformation matrix errors, and then optimize the deployment of the ERS points to reduce the transformation matrix errors. To optimize the deployment of the ERS points, an explicit model is derived to estimate the transformation matrix errors. The estimation model is verified by the experiment implemented in the factory floor. Based on the proposed model, a group of sensitivity coefficients are derived to evaluate the quality of the configuration of the ERS points, and then several typical configurations of the ERS points are analyzed in detail with the sensitivity coefficients. Finally general guidance is established to instruct the deployment of the ERS points in the aspects of the layout, the volume size and the number of the ERS points, as well as the position and orientation of the assembly coordinate system. PMID:26402685

Target matching based on multi-view tracking

NASA Astrophysics Data System (ADS)

Liu, Yahui; Zhou, Changsheng

2011-01-01

A feature matching method is proposed based on Maximally Stable Extremal Regions (MSER) and Scale Invariant Feature Transform (SIFT) to solve the problem of the same target matching in multiple cameras. Target foreground is extracted by using frame difference twice and bounding box which is regarded as target regions is calculated. Extremal regions are got by MSER. After fitted into elliptical regions, those regions will be normalized into unity circles and represented with SIFT descriptors. Initial matching is obtained from the ratio of the closest distance to second distance less than some threshold and outlier points are eliminated in terms of RANSAC. Experimental results indicate the method can reduce computational complexity effectively and is also adapt to affine transformation, rotation, scale and illumination.

Structure in the 3D Galaxy Distribution. III. Fourier Transforming the Universe: Phase and Power Spectra

NASA Technical Reports Server (NTRS)

Scargle, Jeffrey D.; Way, M. J.; Gazis, P. G.

2017-01-01

We demonstrate the effectiveness of a relatively straightforward analysis of the complex 3D Fourier transform of galaxy coordinates derived from redshift surveys. Numerical demonstrations of this approach are carried out on a volume-limited sample of the Sloan Digital Sky Survey redshift survey. The direct unbinned transform yields a complex 3D data cube quite similar to that from the Fast Fourier Transform of finely binned galaxy positions. In both cases, deconvolution of the sampling window function yields estimates of the true transform. Simple power spectrum estimates from these transforms are roughly consistent with those using more elaborate methods. The complex Fourier transform characterizes spatial distributional properties beyond the power spectrum in a manner different from (and we argue is more easily interpreted than) the conventional multipoint hierarchy. We identify some threads of modern large-scale inference methodology that will presumably yield detections in new wider and deeper surveys.

Comparison of 2D and 3D wavelet features for TLE lateralization

NASA Astrophysics Data System (ADS)

Jafari-Khouzani, Kourosh; Soltanian-Zadeh, Hamid; Elisevich, Kost; Patel, Suresh

2004-04-01

Intensity and volume features of the hippocampus from MR images of the brain are known to be useful in detecting the abnormality and consequently candidacy of the hippocampus for temporal lobe epilepsy surgery. However, currently, intracranial EEG exams are required to determine the abnormal hippocampus. These exams are lengthy, painful and costly. The aim of this study is to evaluate texture characteristics of the hippocampi from MR images to help physicians determine the candidate hippocampus for surgery. We studied the MR images of 20 epileptic patients. Intracranial EEG results as well as surgery outcome were used as gold standard. The hippocampi were manually segmented by an expert from T1-weighted MR images. Then the segmented regions were mapped on the corresponding FLAIR images for texture analysis. We calculate the average energy features from 2D wavelet transform of each slice of hippocampus as well as the energy features produced by 3D wavelet transform of the whole hippocampus volume. The 2D wavelet transform is calculated both from the original slices as well as from the slices perpendicular to the principal axis of the hippocampus. In order to calculate the 3D wavelet transform we first rotate each hippocampus to fit it in a rectangular prism and then fill the empty area by extrapolating the intensity values. We combine the resulting features with volume feature and compare their ability to distinguish between normal and abnormal hippocampi using linear classifier and fuzzy c-means clustering algorithm. Experimental results show that the texture features can correctly classify the hippocampi.

Automated linking of suspicious findings between automated 3D breast ultrasound volumes

NASA Astrophysics Data System (ADS)

Gubern-Mérida, Albert; Tan, Tao; van Zelst, Jan; Mann, Ritse M.; Karssemeijer, Nico

2016-03-01

Automated breast ultrasound (ABUS) is a 3D imaging technique which is rapidly emerging as a safe and relatively inexpensive modality for screening of women with dense breasts. However, reading ABUS examinations is very time consuming task since radiologists need to manually identify suspicious findings in all the different ABUS volumes available for each patient. Image analysis techniques to automatically link findings across volumes are required to speed up clinical workflow and make ABUS screening more efficient. In this study, we propose an automated system to, given the location in the ABUS volume being inspected (source), find the corresponding location in a target volume. The target volume can be a different view of the same study or the same view from a prior examination. The algorithm was evaluated using 118 linkages between suspicious abnormalities annotated in a dataset of ABUS images of 27 patients participating in a high risk screening program. The distance between the predicted location and the center of the annotated lesion in the target volume was computed for evaluation. The mean ± stdev and median distance error achieved by the presented algorithm for linkages between volumes of the same study was 7.75±6.71 mm and 5.16 mm, respectively. The performance was 9.54±7.87 and 8.00 mm (mean ± stdev and median) for linkages between volumes from current and prior examinations. The proposed approach has the potential to minimize user interaction for finding correspondences among ABUS volumes.

Evaluation of procedures for prediction of unconventional gas in the presence of geologic trends

USGS Publications Warehouse

Attanasi, E.D.; Coburn, T.C.

2009-01-01

This study extends the application of local spatial nonparametric prediction models to the estimation of recoverable gas volumes in continuous-type gas plays to regimes where there is a single geologic trend. A transformation is presented, originally proposed by Tomczak, that offsets the distortions caused by the trend. This article reports on numerical experiments that compare predictive and classification performance of the local nonparametric prediction models based on the transformation with models based on Euclidean distance. The transformation offers improvement in average root mean square error when the trend is not severely misspecified. Because of the local nature of the models, even those based on Euclidean distance in the presence of trends are reasonably robust. The tests based on other model performance metrics such as prediction error associated with the high-grade tracts and the ability of the models to identify sites with the largest gas volumes also demonstrate the robustness of both local modeling approaches. ?? International Association for Mathematical Geology 2009.

Heat storage in alloy transformations

NASA Technical Reports Server (NTRS)

Birchenall, C. E.

1980-01-01

The feasibility of using metal alloys as thermal energy storage media was investigated. The elements selected as candidate media were limited to aluminum, copper, magnesium, silicon, zinc, calcium, and phosphorus on the basis of low cost and latent heat of transformation. Several new eutectic alloys and ternary intermetallic phases were determined. A new method employing X-ray absorption techniques was developed to determine the coefficients of thermal expansion of both the solid and liquid phases and the volume change during phase transformation. The method and apparatus are discussed and the experimental results are presented for aluminum and two aluminum-eutectic alloys. Candidate materials were evaluated to determine suitable materials for containment of the metal alloys. Graphite was used to contain the alloys during the volume change measurements. Silicon carbide was identified as a promising containment material and surface-coated iron alloys were also evaluated. System considerations that are pertinent if alloy eutectics are used as thermal energy storage media are discussed. Potential applications to solar receivers and industrial furnaces are illustrated schematically.

In situ TEM near-field optical probing of nanoscale silicon crystallization.

PubMed

Xiang, Bin; Hwang, David J; In, Jung Bin; Ryu, Sang-Gil; Yoo, Jae-Hyuck; Dubon, Oscar; Minor, Andrew M; Grigoropoulos, Costas P

2012-05-09

Laser-based processing enables a wide variety of device configurations comprising thin films and nanostructures on sensitive, flexible substrates that are not possible with more traditional thermal annealing schemes. In near-field optical probing, only small regions of a sample are illuminated by the laser beam at any given time. Here we report a new technique that couples the optical near-field of the laser illumination into a transmission electron microscope (TEM) for real-time observations of the laser-materials interactions. We apply this technique to observe the transformation of an amorphous confined Si volume to a single crystal of Si using laser melting. By confinement of the material volume to nanometric dimensions, the entire amorphous precursor is within the laser spot size and transformed into a single crystal. This observation provides a path for laser processing of single-crystal seeds from amorphous precursors, a potentially transformative technique for the fabrication of solar cells and other nanoelectronic devices.

Plasma volume methodology: Evans blue, hemoglobin-hematocrit, and mass density transformations

NASA Technical Reports Server (NTRS)

Greenleaf, J. E.; Hinghofer-Szalkay, H.

1985-01-01

Methods for measuring absolute levels and changes in plasma volume are presented along with derivations of pertinent equations. Reduction in variability of the Evans blue dye dilution technique using chromatographic column purification suggests that the day-to-day variability in the plasma volume in humans is less than + or - 20 m1. Mass density determination using the mechanical-oscillator technique provides a method for measuring vascular fluid shifts continuously for assessing the density of the filtrate, and for quantifying movements of protein across microvascular walls. Equations for the calculation of volume and density of shifted fluid are presented.

Assessing the relationship between ad volume and awareness of a tobacco education media campaign

PubMed Central

Modayil, Mary V; Stevens, Colleen

2010-01-01

Background The relation between aided ad recall and level of television ad placement in a public health setting is not well established. We examine this association by looking back at 8 years of the California's Tobacco Control Program's (CTCP) media campaign. Methods Starting in July 2001, California's campaign was continuously monitored using five telephone series of surveys and six web-based series of surveys immediately following a media flight. We used population-based statewide surveys to measure aided recall for advertisements that were placed in each of these media flights. Targeted rating points (TRPs) were used to measure ad placement intensity throughout the state. Results Cumulative TRPs exhibited a stronger relation with aided ad recall than flight TRPs or TRP density. This association increased after log-transforming cumulative TRP values. We found that a one-unit increase in log-cumulative TRPs led to a 13.6% increase in aided ad recall using web-based survey data, compared to a 5.3% increase in aided ad recall using telephone survey data. Conclusions In California, the relation between aided ad recall and cumulative TRPs showed a diminishing return after a large volume of ad placements These findings may be useful in planning future ad placement for CTCP's media campaign. PMID:20382649

Method for accurate quantitation of background tissue optical properties in the presence of emission from a strong fluorescence marker

NASA Astrophysics Data System (ADS)

Bravo, Jaime; Davis, Scott C.; Roberts, David W.; Paulsen, Keith D.; Kanick, Stephen C.

2015-03-01

Quantification of targeted fluorescence markers during neurosurgery has the potential to improve and standardize surgical distinction between normal and cancerous tissues. However, quantitative analysis of marker fluorescence is complicated by tissue background absorption and scattering properties. Correction algorithms that transform raw fluorescence intensity into quantitative units, independent of absorption and scattering, require a paired measurement of localized white light reflectance to provide estimates of the optical properties. This study focuses on the unique problem of developing a spectral analysis algorithm to extract tissue absorption and scattering properties from white light spectra that contain contributions from both elastically scattered photons and fluorescence emission from a strong fluorophore (i.e. fluorescein). A fiber-optic reflectance device was used to perform measurements in a small set of optical phantoms, constructed with Intralipid (1% lipid), whole blood (1% volume fraction) and fluorescein (0.16-10 μg/mL). Results show that the novel spectral analysis algorithm yields accurate estimates of tissue parameters independent of fluorescein concentration, with relative errors of blood volume fraction, blood oxygenation fraction (BOF), and the reduced scattering coefficient (at 521 nm) of <7%, <1%, and <22%, respectively. These data represent a first step towards quantification of fluorescein in tissue in vivo.

Transforming Big Data into cancer-relevant insight: An initial, multi-tier approach to assess reproducibility and relevance* | Office of Cancer Genomics

Cancer.gov

The Cancer Target Discovery and Development (CTD^2) Network was established to accelerate the transformation of "Big Data" into novel pharmacological targets, lead compounds, and biomarkers for rapid translation into improved patient outcomes. It rapidly became clear in this collaborative network that a key central issue was to define what constitutes sufficient computational or experimental evidence to support a biologically or clinically relevant finding.

Specific α7 nicotinic acetylcholine receptor agonist ameliorates isoproterenol-induced cardiac remodelling in mice through TGF-β1/Smad3 pathway.

PubMed

Yang, Yong-Hua; Fang, Huan-Le; Zhao, Ming; Wei, Xiang-Lan; Zhang, Ning; Wang, Shun; Lu, Yi; Yu, Xiao-Jiang; Sun, Lei; He, Xi; Li, Dong-Ling; Liu, Jin-Jun; Zang, Wei-Jin

2017-12-01

It is well-accepted that inflammation plays an important role in the development of cardiac remodelling and that therapeutic approaches targeting inflammation can inhibit cardiac remodelling. Although a large amount of evidence indicates that activation of α7 nicotinic acetylcholine receptor (α7nAChR) causes an anti-inflammatory effect, the role of α7nAChR in cardiac remodelling and the underlying mechanism have not been established. To investigate the effect of the specific α7nAChR agonist, PNU282987, on cardiac remodelling induced by isoproterenol (ISO 60 mg/kg per day) in mice, the cardiomyocyte cross-sectional area (CSA) and collagen volume fraction were evaluated by hematoxylin and eosin (HE) and Masson staining, respectively. Cardiac function and ventricular wall thickness were measured by echocardiography. The protein expressions of collagen I, matrix metalloproteinase 9 (MMP-9), transforming growth factor β1 (TGF-β1), and Smad3 were analyzed by Western blot. ISO-induced cardiac hypertrophy, characterized by an increase in the heart weight/body weight ratio, CSA and ventricular wall thickness. Moreover, cardiac fibrosis indices, such as collagen volume fraction, MMP-9 and collagen I protein expression, were also increased by ISO. PNU282987 not only attenuated cardiac hypertrophy but also decreased the cardiac fibrosis induced by ISO. Furthermore, PNU282987 suppressed TGF-β1 protein expression and the phosphorylation of Smad3 induced by ISO. In conclusion, PNU282987 ameliorated the cardiac remodelling induced by ISO, which may be related to the TGF-β1/Smad3 pathway. These data imply that the α7nAChR may represent a novel therapeutic target for cardiac remodelling in many cardiovascular diseases. © 2017 John Wiley & Sons Australia, Ltd.

SU-C-BRA-02: Gradient Based Method of Target Delineation On PET/MR Image of Head and Neck Cancer Patients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dance, M; Chera, B; Falchook, A

2015-06-15

Purpose: Validate the consistency of a gradient-based segmentation tool to facilitate accurate delineation of PET/CT-based GTVs in head and neck cancers by comparing against hybrid PET/MR-derived GTV contours. Materials and Methods: A total of 18 head and neck target volumes (10 primary and 8 nodal) were retrospectively contoured using a gradient-based segmentation tool by two observers. Each observer independently contoured each target five times. Inter-observer variability was evaluated via absolute percent differences. Intra-observer variability was examined by percentage uncertainty. All target volumes were also contoured using the SUV percent threshold method. The thresholds were explored case by case so itsmore » derived volume matched with the gradient-based volume. Dice similarity coefficients (DSC) were calculated to determine overlap of PET/CT GTVs and PET/MR GTVs. Results: The Levene’s test showed there was no statistically significant difference of the variances between the observer’s gradient-derived contours. However, the absolute difference between the observer’s volumes was 10.83%, with a range from 0.39% up to 42.89%. PET-avid regions with qualitatively non-uniform shapes and intensity levels had a higher absolute percent difference near 25%, while regions with uniform shapes and intensity levels had an absolute percent difference of 2% between observers. The average percentage uncertainty between observers was 4.83% and 7%. As the volume of the gradient-derived contours increased, the SUV threshold percent needed to match the volume decreased. Dice coefficients showed good agreement of the PET/CT and PET/MR GTVs with an average DSC value across all volumes at 0.69. Conclusion: Gradient-based segmentation of PET volume showed good consistency in general but can vary considerably for non-uniform target shapes and intensity levels. PET/CT-derived GTV contours stemming from the gradient-based tool show good agreement with the anatomically and metabolically more accurate PET/MR-derived GTV contours, but tumor delineation accuracy can be further improved with the use PET/MR.« less

Bar coded retroreflective target

DOEpatents

Vann, Charles S.

2000-01-01

This small, inexpensive, non-contact laser sensor can detect the location of a retroreflective target in a relatively large volume and up to six degrees of position. The tracker's laser beam is formed into a plane of light which is swept across the space of interest. When the beam illuminates the retroreflector, some of the light returns to the tracker. The intensity, angle, and time of the return beam is measured to calculate the three dimensional location of the target. With three retroreflectors on the target, the locations of three points on the target are measured, enabling the calculation of all six degrees of target position. Until now, devices for three-dimensional tracking of objects in a large volume have been heavy, large, and very expensive. Because of the simplicity and unique characteristics of this tracker, it is capable of three-dimensional tracking of one to several objects in a large volume, yet it is compact, light-weight, and relatively inexpensive. Alternatively, a tracker produces a diverging laser beam which is directed towards a fixed position, and senses when a retroreflective target enters the fixed field of view. An optically bar coded target can be read by the tracker to provide information about the target. The target can be formed of a ball lens with a bar code on one end. As the target moves through the field, the ball lens causes the laser beam to scan across the bar code.

Micromechanics of plastic deformation and phase transformation in a three-phase TRIP-assisted advanced high strength steel: Experiments and modeling

NASA Astrophysics Data System (ADS)

Srivastava, Ankit; Ghassemi-Armaki, Hassan; Sung, Hyokyung; Chen, Peng; Kumar, Sharvan; Bower, Allan F.

2015-05-01

The micromechanics of plastic deformation and phase transformation in a three-phase advanced high strength steel are analyzed both experimentally and by microstructure-based simulations. The steel examined is a three-phase (ferrite, martensite and retained austenite) quenched and partitioned sheet steel with a tensile strength of 980 MPa. The macroscopic flow behavior and the volume fraction of martensite resulting from the austenite-martensite transformation during deformation were measured. In addition, micropillar compression specimens were extracted from the individual ferrite grains and the martensite particles, and using a flat-punch nanoindenter, stress-strain curves were obtained. Finite element simulations idealize the microstructure as a composite that contains ferrite, martensite and retained austenite. All three phases are discretely modeled using appropriate crystal plasticity based constitutive relations. Material parameters for ferrite and martensite are determined by fitting numerical predictions to the micropillar data. The constitutive relation for retained austenite takes into account contributions to the strain rate from the austenite-martensite transformation, as well as slip in both the untransformed austenite and product martensite. Parameters for the retained austenite are then determined by fitting the predicted flow stress and transformed austenite volume fraction in a 3D microstructure to experimental measurements. Simulations are used to probe the role of the retained austenite in controlling the strain hardening behavior as well as internal stress and strain distributions in the microstructure.

Combining registration and active shape models for the automatic segmentation of the lymph node regions in head and neck CT images

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen Antong; Deeley, Matthew A.; Niermann, Kenneth J.

2010-12-15

Purpose: Intensity-modulated radiation therapy (IMRT) is the state of the art technique for head and neck cancer treatment. It requires precise delineation of the target to be treated and structures to be spared, which is currently done manually. The process is a time-consuming task of which the delineation of lymph node regions is often the longest step. Atlas-based delineation has been proposed as an alternative, but, in the authors' experience, this approach is not accurate enough for routine clinical use. Here, the authors improve atlas-based segmentation results obtained for level II-IV lymph node regions using an active shape model (ASM)more » approach. Methods: An average image volume was first created from a set of head and neck patient images with minimally enlarged nodes. The average image volume was then registered using affine, global, and local nonrigid transformations to the other volumes to establish a correspondence between surface points in the atlas and surface points in each of the other volumes. Once the correspondence was established, the ASMs were created for each node level. The models were then used to first constrain the results obtained with an atlas-based approach and then to iteratively refine the solution. Results: The method was evaluated through a leave-one-out experiment. The ASM- and atlas-based segmentations were compared to manual delineations via the Dice similarity coefficient (DSC) for volume overlap and the Euclidean distance between manual and automatic 3D surfaces. The mean DSC value obtained with the ASM-based approach is 10.7% higher than with the atlas-based approach; the mean and median surface errors were decreased by 13.6% and 12.0%, respectively. Conclusions: The ASM approach is effective in reducing segmentation errors in areas of low CT contrast where purely atlas-based methods are challenged. Statistical analysis shows that the improvements brought by this approach are significant.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

You, D; Aryal, M; Samuels, S

Purpose: A previous study showed that large sub-volumes of tumor with low blood volume (BV) (poorly perfused) in head-and-neck (HN) cancers are significantly associated with local-regional failure (LRF) after chemoradiation therapy, and could be targeted with intensified radiation doses. This study aimed to develop an automated and scalable model to extract voxel-wise contrast-enhanced temporal features of dynamic contrastenhanced (DCE) MRI in HN cancers for predicting LRF. Methods: Our model development consists of training and testing stages. The training stage includes preprocessing of individual-voxel DCE curves from tumors for intensity normalization and temporal alignment, temporal feature extraction from the curves, featuremore » selection, and training classifiers. For feature extraction, multiresolution Haar discrete wavelet transformation is applied to each DCE curve to capture temporal contrast-enhanced features. The wavelet coefficients as feature vectors are selected. Support vector machine classifiers are trained to classify tumor voxels having either low or high BV, for which a BV threshold of 7.6% is previously established and used as ground truth. The model is tested by a new dataset. The voxel-wise DCE curves for training and testing were from 14 and 8 patients, respectively. A posterior probability map of the low BV class was created to examine the tumor sub-volume classification. Voxel-wise classification accuracy was computed to evaluate performance of the model. Results: Average classification accuracies were 87.2% for training (10-fold crossvalidation) and 82.5% for testing. The lowest and highest accuracies (patient-wise) were 68.7% and 96.4%, respectively. Posterior probability maps of the low BV class showed the sub-volumes extracted by our model similar to ones defined by the BV maps with most misclassifications occurred near the sub-volume boundaries. Conclusion: This model could be valuable to support adaptive clinical trials with further validation. The framework could be extendable and scalable to extract temporal contrastenhanced features of DCE-MRI in other tumors. We would like to acknowledge NIH for funding support: UO1 CA183848.« less

Transformation diffusion reconstruction of three-dimensional histology volumes from two-dimensional image stacks.

PubMed

Casero, Ramón; Siedlecka, Urszula; Jones, Elizabeth S; Gruscheski, Lena; Gibb, Matthew; Schneider, Jürgen E; Kohl, Peter; Grau, Vicente

2017-05-01

Traditional histology is the gold standard for tissue studies, but it is intrinsically reliant on two-dimensional (2D) images. Study of volumetric tissue samples such as whole hearts produces a stack of misaligned and distorted 2D images that need to be reconstructed to recover a congruent volume with the original sample's shape. In this paper, we develop a mathematical framework called Transformation Diffusion (TD) for stack alignment refinement as a solution to the heat diffusion equation. This general framework does not require contour segmentation, is independent of the registration method used, and is trivially parallelizable. After the first stack sweep, we also replace registration operations by operations in the space of transformations, several orders of magnitude faster and less memory-consuming. Implementing TD with operations in the space of transformations produces our Transformation Diffusion Reconstruction (TDR) algorithm, applicable to general transformations that are closed under inversion and composition. In particular, we provide formulas for translation and affine transformations. We also propose an Approximated TDR (ATDR) algorithm that extends the same principles to tensor-product B-spline transformations. Using TDR and ATDR, we reconstruct a full mouse heart at pixel size 0.92µm×0.92µm, cut 10µm thick, spaced 20µm (84G). Our algorithms employ only local information from transformations between neighboring slices, but the TD framework allows theoretical analysis of the refinement as applying a global Gaussian low-pass filter to the unknown stack misalignments. We also show that reconstruction without an external reference produces large shape artifacts in a cardiac specimen while still optimizing slice-to-slice alignment. To overcome this problem, we use a pre-cutting blockface imaging process previously developed by our group that takes advantage of Brewster's angle and a polarizer to capture the outline of only the topmost layer of wax in the block containing embedded tissue for histological sectioning. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

SU-E-T-287: Dose Verification On the Variation of Target Volume and Organ at Risk in Preradiation Chemotherapy IMRT for Nasopharyngeal Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, X; Kong, L; Wang, J

2015-06-15

Purpose: To quantify the target volume and organ at risk of nasopharyngeal carcinoma (NPC) patients with preradiation chemotherapy based on CT scanned during intensity-modulated radiotherapy (IMRT), and recalculate the dose distribution. Methods: Seven patients with NPC and preradiation chemotherapy, treated with IMRT (35 to 37 fractions) were reviewed. Repeat CT scanning was required to all of the patients during the radiotherapy, and the number of repeat CTs varies from 2 to 6. The plan CT and repeat CT were generated by different CT scanner. To ensure crespectively on the same IMPT plan. The real dose distribution was calculated by deformablemore » registration and weighted method in Raystation (v 4.5.1). The fraction of each dose is based on radiotherapy record. The volumetric and dose differences among these images were calculated for nascIpharyngeal tumor and retro-pharyngeal lymph nodes (GTV-NX), neck lymph nodes(GTV-ND), and parotid glands. Results: The volume variation in GTV-NX from CT1 to CT2 was 1.15±3.79%, and in GTV-LN −0.23±4.93%. The volume variation in left parotid from CT1 to CT2 was −6.79±11.91%, and in right parotid −3.92±8.80%. In patient 2, the left parotid volume were decreased remarkably, as a Result, the V30 and V40 of it were increased as well. Conclusion: The target volume of patients with NPC varied lightly during IMRT. It shows that preradiation chemotherapy can control the target volume variation and perform a good dose repeatability. Also, the decreasing volume of parotid in some patient might increase the dose of it, which might course potential complications.« less

The application of positron emission tomography/computed tomography in radiation treatment planning: effect on gross target volume definition and treatment management.

PubMed

Iğdem, S; Alço, G; Ercan, T; Unalan, B; Kara, B; Geceer, G; Akman, C; Zengin, F O; Atilla, S; Okkan, S

2010-04-01

To analyse the effect of the use of molecular imaging on gross target volume (GTV) definition and treatment management. Fifty patients with various solid tumours who underwent positron emission tomography (PET)/computed tomography (CT) simulation for radiotherapy planning from 2006 to 2008 were enrolled in this study. First, F-18 fluorodeoxyglucose (FDG)-PET and CT scans of the treatment site in the treatment position and then a whole body scan were carried out with a dedicated PET/CT scanner and fused thereafter. FDG-avid primary tumour and lymph nodes were included into the GTV. A multidisciplinary team defined the target volume, and contouring was carried out by a radiation oncologist using visual methods. To compare the PET/CT-based volumes with CT-based volumes, contours were drawn on CT-only data with the help of site-specific radiologists who were blind to the PET/CT results after a median time of 7 months. In general, our PET/CT volumes were larger than our CT-based volumes. This difference was significant in patients with head and neck cancers. Major changes (> or =25%) in GTV delineation were observed in 44% of patients. In 16% of cases, PET/CT detected incidental second primaries and metastatic disease, changing the treatment strategy from curative to palliative. Integrating functional imaging with FDG-PET/CT into the radiotherapy planning process resulted in major changes in a significant proportion of our patients. An interdisciplinary approach between imaging and radiation oncology departments is essential in defining the target volumes. Copyright 2010 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

Entanglement-assisted transformation is asymptotically equivalent to multiple-copy transformation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Duan Runyao; Feng Yuan; Ying Mingsheng

2005-08-15

We show that two ways of manipulating quantum entanglement - namely, entanglement-assisted local transformation [D. Jonathan and M. B. Plenio, Phys. Rev. Lett. 83, 3566 (1999)] and multiple-copy transformation [S. Bandyopadhyay, V. Roychowdhury, and U. Sen, Phys. Rev. A 65, 052315 (2002)]--are equivalent in the sense that they can asymptotically simulate each other's ability to implement a desired transformation from a given source state to another given target state with the same optimal success probability. As a consequence, this yields a feasible method to evaluate the optimal conversion probability of an entanglement-assisted transformation.

Ultra-low field nuclear magnetic resonance and magnetic resonance imaging to discriminate and identify materials

DOEpatents

Kraus, Robert H.; Matlashov, Andrei N.; Espy, Michelle A.; Volegov, Petr L.

2010-03-30

An ultra-low magnetic field NMR system can non-invasively examine containers. Database matching techniques can then identify hazardous materials within the containers. Ultra-low field NMR systems are ideal for this purpose because they do not require large powerful magnets and because they can examine materials enclosed in conductive shells such as lead shells. The NMR examination technique can be combined with ultra-low field NMR imaging, where an NMR image is obtained and analyzed to identify target volumes. Spatial sensitivity encoding can also be used to identify target volumes. After the target volumes are identified the NMR measurement technique can be used to identify their contents.

Cooling Concepts for High Power Density Magnetic Devices

NASA Astrophysics Data System (ADS)

Biela, Juergen; Kolar, Johann W.

In the area or power electronics there is a general trend to higher power densities. In order to increase the power density the systems must be designed optimally concerning topology, semiconductor selection, etc. and the volume of the components must be decreased. The decreasing volume comes along with a reduced surface for cooling. Consequently, new cooling methods are required. In the paper an indirect air cooling system for magnetic devices which combines the transformer with a heat sink and a heat transfer component is presented. Moreover, an analytic approach for calculating the temperature distribution is derived and validated by measurements. Based on these equations a transformer with an indirect air cooling system is designed for a 10kW telecom power supply.

NLT and extrapolated DLT:3-D cinematography alternatives for enlarging the volume of calibration.

PubMed

Hinrichs, R N; McLean, S P

1995-10-01

This study investigated the accuracy of the direct linear transformation (DLT) and non-linear transformation (NLT) methods of 3-D cinematography/videography. A comparison of standard DLT, extrapolated DLT, and NLT calibrations showed the standard (non-extrapolated) DLT to be the most accurate, especially when a large number of control points (40-60) were used. The NLT was more accurate than the extrapolated DLT when the level of extrapolation exceeded 100%. The results indicated that when possible one should use the DLT with a control object, sufficiently large as to encompass the entire activity being studied. However, in situations where the activity volume exceeds the size of one's DLT control object, the NLT method should be considered.

Predictors of clinical outcome in emphysema patients with atelectasis following endoscopic valve therapy: A retrospective study.

PubMed

Gompelmann, Daniela; Hofbauer, Tobias; Gerovasili, Vasiliki; Eberhardt, Ralf; Lim, Hyun-Ju; Herth, Felix; Heussel, Claus-Peter

2016-10-01

The aim of endoscopic valve therapy in patients with emphysema is complete lobar atelectasis of the most emphysematous lobe. However, even after the radiological advent of atelectasis, great variability in clinical outcomes can be observed. The baseline clinical measures (vital capacity (VC), forced expiratory flow in 1 s (FEV1 ), residual volume (RV) and 6-min walk test (6-MWT)) and computed tomography variables (low attenuation volume (LAV) of the target lobe, LAV% of the target and the ipsilateral untreated lobe and LAV of the target lobe to LAV of the target lung and to LAV of the total lung) of 77 patients with complete atelectasis following valve therapy were retrospectively examined to determine their impact on patient´s outcome (changes in VC, FEV1 , RV and 6-MWT from baseline to the time of atelectasis). Low attenuation volume of the target lobe to LAV of the target lung predicts a significant FEV1 improvement in patients with complete lobar atelectasis following valve therapy. A 10% difference in that computed tomography predictor was associated with a 82-mL improvement in FEV1 (P = 0.006). Lower 6-MWT scores, low VC and high RV at baseline were significantly associated with greater improvement in the respective parameter (all P < 0.001). Low attenuation volume of the target lobe to LAV of the target lung and baseline clinical measures seem to significantly predict clinical outcomes in patients with complete lobar atelectasis following valve treatment. © 2016 Asian Pacific Society of Respirology.

A Hough transform global probabilistic approach to multiple-subject diffusion MRI tractography.

PubMed

Aganj, Iman; Lenglet, Christophe; Jahanshad, Neda; Yacoub, Essa; Harel, Noam; Thompson, Paul M; Sapiro, Guillermo

2011-08-01

A global probabilistic fiber tracking approach based on the voting process provided by the Hough transform is introduced in this work. The proposed framework tests candidate 3D curves in the volume, assigning to each one a score computed from the diffusion images, and then selects the curves with the highest scores as the potential anatomical connections. The algorithm avoids local minima by performing an exhaustive search at the desired resolution. The technique is easily extended to multiple subjects, considering a single representative volume where the registered high-angular resolution diffusion images (HARDI) from all the subjects are non-linearly combined, thereby obtaining population-representative tracts. The tractography algorithm is run only once for the multiple subjects, and no tract alignment is necessary. We present experimental results on HARDI volumes, ranging from simulated and 1.5T physical phantoms to 7T and 4T human brain and 7T monkey brain datasets. Copyright © 2011 Elsevier B.V. All rights reserved.

Mining influence on underground water resources in arid and semiarid regions

NASA Astrophysics Data System (ADS)

Luo, A. K.; Hou, Y.; Hu, X. Y.

2018-02-01

Coordinated mining of coal and water resources in arid and semiarid regions has traditionally become a focus issue. The research takes Energy and Chemical Base in Northern Shaanxi as an example, and conducts statistical analysis on coal yield and drainage volume from several large-scale mines in the mining area. Meanwhile, research determines average water volume per ton coal, and calculates four typical years’ drainage volume in different mining intensity. Then during mining drainage, with the combination of precipitation observation data in recent two decades and water level data from observation well, the calculation of groundwater table, precipitation infiltration recharge, and evaporation capacity are performed. Moreover, the research analyzes the transforming relationship between surface water, mine water, and groundwater. The result shows that the main reason for reduction of water resources quantity and transforming relationship between surface water, groundwater, and mine water is massive mine drainage, which is caused by large-scale coal mining in the research area.

High Pressure Phase Transformations in Heavy Rare Earth Metals and Connections to Actinide Crystal Structures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vohra, Yogesh K.; Sangala, Bagvanth Reddy; Stemshorn, Andrew K.

2008-07-01

High-pressure studies have been performed on heavy rare earth metals Terbium (Tb) to 155 GPa and Holmium (Ho) to 134 GPa in a diamond anvil cell at room temperature. The following crystal structure sequence was observed in both metals hcp {yields} Sm-type {yields} dhcp {yields} distorted fcc (hR-24) {yields} monoclinic (C2/m) with increasing pressure. The last transformation to a low symmetry monoclinic phase is accompanied by a volume collapse of 5 % for Tb at 51 GPa and a volume collapse of 3 % for Ho at 103 GPa. This volume collapse under high pressure is reminiscent of f-shell delocalizationmore » in light rare earth metal Cerium (Ce), Praseodymium (Pr), and heavy actinide metals Americium (Am) and Curium (Cm). The orthorhombic Pnma phase that has been reported in Am and Cm after f-shell delocalization is not observed in heavy rare earth metals under high pressures. (authors)« less

Distributed ISAR Subimage Fusion of Nonuniform Rotating Target Based on Matching Fourier Transform.

PubMed

Li, Yuanyuan; Fu, Yaowen; Zhang, Wenpeng

2018-06-04

In real applications, the image quality of the conventional monostatic Inverse Synthetic Aperture Radar (ISAR) for the maneuvering target is subject to the strong fluctuation of Radar Cross Section (RCS), as the target aspect varies enormously. Meanwhile, the maneuvering target introduces nonuniform rotation after translation motion compensation which degrades the imaging performance of the conventional Fourier Transform (FT)-based method in the cross-range dimension. In this paper, a method which combines the distributed ISAR technique and the Matching Fourier Transform (MFT) is proposed to overcome these problems. Firstly, according to the characteristics of the distributed ISAR, the multiple channel echoes of the nonuniform rotation target from different observation angles can be acquired. Then, by applying the MFT to the echo of each channel, the defocused problem of nonuniform rotation target which is inevitable by using the FT-based imaging method can be avoided. Finally, after preprocessing, scaling and rotation of all subimages, the noncoherent fusion image containing all the RCS information in all channels can be obtained. The accumulation coefficients of all subimages are calculated adaptively according to the their image qualities. Simulation and experimental data are used to validate the effectiveness of the proposed approach, and fusion image with improved recognizability can be obtained. Therefore, by using the distributed ISAR technique and MFT, subimages of high-maneuvering target from different observation angles can be obtained. Meanwhile, by employing the adaptive subimage fusion method, the RCS fluctuation can be alleviated and more recognizable final image can be obtained.

Discrimination between landmine and mine-like targets using wavelets and spectral analysis

NASA Astrophysics Data System (ADS)

Mohana, Mahmoud A.; Abbas, Abbas M.; Gomaa, Mohamed L.; Ebrahim, Shereen M.

2013-06-01

Landmine is an explosive apparatus hidden in or on the ground, which blows up when a person or vehicle passes over it. Egypt is one of the countries suffering due to the unexploded ordnance (UXO). Around 2 million UXO are present in the Egyptian soil especially at Al-Alameen province, north of the western desert. Detection of buried landmines is a problem of military and humanitarian importance. Ground penetrating radar (GPR) is a powerful and non-destructive geophysical approach with a wide range of advantages in the field of landmine inspection. In the present paper, we apply different simulation models with Vivaldi antenna and mine-like targets by using the CST Microwave studio program. The field work is carried out by using a GPR device of model SIR 2000 from GSSI (Geophysical Survey Systems Incorporation) connected to 900 MHz antenna where the targets were buried in sand soil. Depending on the fact that the receiving powers (reflected, refracted and scattered) from the different materials are different, we study the spectral power densities for the received power from the different targets. The techniques used in this study are: direct fast Fourier transform, short time Fourier transform (spectrogram), wavelets transform and denoising techniques. Our results ought to be considered as finger prints for different scanned targets during this work. So we can discriminate between landmines and mine-like targets.

Foundations for Streaming Model Transformations by Complex Event Processing.

PubMed

Dávid, István; Ráth, István; Varró, Dániel

2018-01-01

Streaming model transformations represent a novel class of transformations to manipulate models whose elements are continuously produced or modified in high volume and with rapid rate of change. Executing streaming transformations requires efficient techniques to recognize activated transformation rules over a live model and a potentially infinite stream of events. In this paper, we propose foundations of streaming model transformations by innovatively integrating incremental model query, complex event processing (CEP) and reactive (event-driven) transformation techniques. Complex event processing allows to identify relevant patterns and sequences of events over an event stream. Our approach enables event streams to include model change events which are automatically and continuously populated by incremental model queries. Furthermore, a reactive rule engine carries out transformations on identified complex event patterns. We provide an integrated domain-specific language with precise semantics for capturing complex event patterns and streaming transformations together with an execution engine, all of which is now part of the Viatra reactive transformation framework. We demonstrate the feasibility of our approach with two case studies: one in an advanced model engineering workflow; and one in the context of on-the-fly gesture recognition.

Intravesical markers for delineation of target volume during external focal irradiation of bladder carcinomas.

PubMed

Hulshof, Maarten C C M; van Andel, George; Bel, Arjen; Gangel, Pieter; van de Kamer, Jeroen B

2007-07-01

A clip forceps was developed which can insert markers at the border of a bladder tumour through a rigid cystoscope. This technique proved to be simple and safe and is of help for delineation of the target volume during CT simulation for focal boost irradiation of bladder cancer.

Intra-fraction motion of larynx radiotherapy

NASA Astrophysics Data System (ADS)

Durmus, Ismail Faruk; Tas, Bora

2018-02-01

In early stage laryngeal radiotherapy, movement is an important factor. Thyroid cartilage can move from swallowing, breathing, sound and reflexes. The effects of this motion on the target volume (PTV) during treatment were examined. In our study, the target volume movement during the treatment for this purpose was examined. Thus, setup margins are re-evaluated and patient-based PTV margins are determined. Intrafraction CBCT was scanned in 246 fractions for 14 patients. During the treatment, the amount of deviation which could be lateral, vertical and longitudinal axis was determined. ≤ ± 0.1cm deviation; 237 fractions in the lateral direction, 202 fractions in the longitudinal direction, 185 fractions in the vertical direction. The maximum deviation values were found in the longitudinal direction. Intrafraction guide in laryngeal radiotherapy; we are sure of the correctness of the treatment, the target volume is to adjust the margin and dose more precisely, we control the maximum deviation of the target volume for each fraction. Although the image quality of intrafraction-CBCT scans was lower than the image quality of planning CT, they showed sufficient contrast for this work.

Using injectable hydrogel markers to assess resimulation for boost target volume definition in a patient undergoing whole-breast radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Patel, Henal; Goyal, Sharad; Kim, Leonard, E-mail: kimlh@rutgers.edu

Several publications have recommended that patients undergoing whole-breast radiotherapy be resimulated for boost planning. The rationale for this is that the seroma may be smaller when compared with the initial simulation. However, the decision remains whether to use the earlier or later images to define an appropriate boost target volume. A patient undergoing whole-breast radiotherapy had new, injectable, temporary hydrogel fiducial markers placed 1 to 3 cm from the seroma at the time of initial simulation. The patient was resimulated 4.5 weeks later for conformal photon boost planning. Computed tomography (CT) scans acquired at the beginning and the end ofmore » whole-breast radiotherapy showed that shrinkage of the lumpectomy cavity was not matched by a corresponding reduction in the surrounding tissue volume, as demarcated by hydrogel markers. This observation called into question the usual interpretation of cavity shrinkage for boost target definition. For this patient, it was decided to define the boost target volume on the initial planning CT instead of the new CT.« less

Analysis of radiation exposure for naval units of Operation Crossroads. Volume 3. (Appendix B) support ships. Technical report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weitz, R.; Thomas, C.; Klemm, J.

1982-03-03

External radiation doses are reconstructed for crews of support and target ships of Joint Task Force One at Operation CROSSROADS, 1946. Volume I describes the reconstruction methodology, which consists of modeling the radiation environment, to include the radioactivity of lagoon water, target ships, and support ship contamination; retracing ship paths through this environment; and calculating the doses to shipboard personnel. The USS RECLAIMER, a support ship, is selected as a representative ship to demonstrate this methodology. Doses for all other ships are summarized. Volume II (Appendix A) details the results for target ship personnel. Volume III (Appendix B) details themore » results for support ship personnel. Calculated doses for more than 36,000 personnel aboard support ships while at Bikini range from zero to 1.7 rem. Of those approximately 34,000 are less than 0.5 rem. From the models provided, doses due to target ship reboarding and doses accrued after departure from Bikini can be calculated, based on the individual circumstances of exposure.« less

The role of PET in target localization for radiotherapy treatment planning.

PubMed

Rembielak, Agata; Price, Pat

2008-02-01

Positron emission tomography (PET) is currently accepted as an important tool in oncology, mostly for diagnosis, staging and restaging purposes. It provides a new type of information in radiotherapy, functional rather than anatomical. PET imaging can also be used for target volume definition in radiotherapy treatment planning. The need for very precise target volume delineation has arisen with the increasing use of sophisticated three-dimensional conformal radiotherapy techniques and intensity modulated radiation therapy. It is expected that better delineation of the target volume may lead to a significant reduction in the irradiated volume, thus lowering the risk of treatment complications (smaller safety margins). Better tumour visualisation also allows a higher dose of radiation to be applied to the tumour, which may lead to better tumour control. The aim of this article is to review the possible use of PET imaging in the radiotherapy of various cancers. We focus mainly on non-small cell lung cancer, lymphoma and oesophageal cancer, but also include current opinion on the use of PET-based planning in other tumours including brain, uterine cervix, rectum and prostate.

Displacive Transformation in Ceramics

DTIC Science & Technology

1994-02-28

product However, the evidence here is thin because no other interface which, during transformation movement, pro - crystallographic data were used other... con - and the parent phase. stants c and a change abruptly and the structure becomles The phenomenological crystallographic theory of cubic. Since the...detectable negative volume change near T,, PbTiO3 Pro * vides a more sensitve indication of the role of lattice vari- Department of Matcrials Science

About the choice of Gibbs' potential for modelling of FCC ↔ HCP transformation in FeMnSi-based shape memory alloys

NASA Astrophysics Data System (ADS)

Evard, Margarita E.; Volkov, Aleksandr E.; Belyaev, Fedor S.; Ignatova, Anna D.

2018-05-01

The choice of Gibbs' potential for microstructural modeling of FCC ↔ HCP martensitic transformation in FeMn-based shape memory alloys is discussed. Threefold symmetry of the HCP phase is taken into account on specifying internal variables characterizing volume fractions of martensite variants. Constraints imposed on model constants by thermodynamic equilibrium conditions are formulated.

The experimental study of the DC dielectric breakdown strength in magnetic fluids

NASA Astrophysics Data System (ADS)

Kopčanský, P.; Tomčo, L.; Marton, K.; Koneracká, M.; Potočová, I.; Timko, M.

2004-05-01

Magnetic fluids have been studied for use as a high-voltage insulation. High-voltage measurements on magnetic fluids based on transformer oil, as a function of volume concentrations of magnetite particles and applied magnetic field, showed the increase of the DC dielectric breakdown strength opposite transformer oil, if the saturation magnetization of magnetic fluid is up to 4 mT approximately.

LLE Review Quarterly Report (October - December 2007). Volume 113

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zuegel, Jonathan D.

2007-12-01

This volume of the LLE Review, covering October–December 2007, features “High-Intensity Laser–Plasma Interactions in the Refluxing Limit,” by P. M. Nilson, W. Theobald, J. Myatt, C. Stoeckl, M. Storm, O. V. Gotchev, J. D. Zuegel, R. Betti, D. D. Meyerhofer, and T. C. Sangster. In this article (p. 1), the authors report on target experiments using the Multi-Terawatt (MTW) Laser Facility to study isochoric heating of solid-density targets by fast electrons produced from intense, short-pulse laser irradiation. Electron refluxing occurs due to target-sheath field effects and contains most of the fast electrons within the target volume. This efficiently heats themore » solid-density plasma through collisions. X-ray spectroscopic measurements of absolute K α (x-radiation) photon yields and variations of the K β/K α b emission ratio both indicate that laser energy couples to fast electrons with a conversion efficiency of approximately 20%. Bulk electron temperatures of at least 200 eV are inferred for the smallest mass targets.« less

Doses to organs and tissues from concomitant imaging in radiotherapy: a suggested framework for clinical justification.

PubMed

Harrison, R M

2008-12-01

The increasing use of imaging for localization and verification in radiotherapy has raised issues concerning the justifiable doses to critical organs and tissues from concomitant exposures, particularly when extensive image-guided radiotherapy is indicated. Doses at positions remote from the target volume include components from high-energy leakage and scatter, as well as from concomitant imaging. In this paper, simulated prostate, breast and larynx treatments are used to compare doses from both high-energy and concomitant exposures as a function of distance from the target volume. It is suggested that the fraction, R, of the total dose at any point within the patient that is attributable to concomitant exposures may be a useful aid in their justification. R is small within the target volume and at large distances from it. However, there is a critical region immediately adjacent to the planning target volume where the dose from concomitant imaging combines with leakage and scatter to give values of R that approach 0.5 in the examples given here. This is noteworthy because the regions just outside the target volume will receive total doses in the order of 1 Gy, where commensurately high risk factors may not be substantially reduced because of cell kill. Other studies have identified these regions as sites of second cancers. The justification of an imaging regimen might therefore usefully take into account the maximum value of R encountered from the combination of imaging and radiotherapy for particular treatment sites.

Effects of online cone-beam computed tomography with active breath control in determining planning target volume during accelerated partial breast irradiation.

PubMed

Li, Y; Zhong, R; Wang, X; Ai, P; Henderson, F; Chen, N; Luo, F

2017-04-01

To test if active breath control during cone-beam computed tomography (CBCT) could improve planning target volume during accelerated partial breast radiotherapy for breast cancer. Patients who were more than 40 years old, underwent breast-conserving dissection and planned for accelerated partial breast irradiation, and with postoperative staging limited to T1-2 N0 M0, or postoperative staging T2 lesion no larger than 3cm with a negative surgical margin greater than 2mm were enrolled. Patients with lobular carcinoma or extensive ductal carcinoma in situ were excluded. CBCT images were obtained pre-correction, post-correction and post-treatment. Set-up errors were recorded at left-right, anterior-posterior and superior-inferior directions. The differences between these CBCT images, as well as calculated radiation doses, were compared between patients with active breath control or free breathing. Forty patients were enrolled, among them 25 had active breath control. A total of 836 CBCT images were obtained for analysis. CBCT significantly reduced planning target volume. However, active breath control did not show significant benefit in decreasing planning target volume margin and the doses of organ-at-risk when compared to free breathing. CBCT, but not active breath control, could reduce planning target volume during accelerated partial breast irradiation. Copyright © 2017 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

Dim target trajectory-associated detection in bright earth limb background

NASA Astrophysics Data System (ADS)

Chen, Penghui; Xu, Xiaojian; He, Xiaoyu; Jiang, Yuesong

2015-09-01

The intensive emission of earth limb in the field of view of sensors contributes much to the observation images. Due to the low signal-to-noise ratio (SNR), it is a challenge to detect small targets in earth limb background, especially for the detection of point-like targets from a single frame. To improve the target detection, track before detection (TBD) based on the frame sequence is performed. In this paper, a new technique is proposed to determine the target associated trajectories, which jointly carries out background removing, maximum value projection (MVP) and Hough transform. The background of the bright earth limb in the observation images is removed according to the profile characteristics. For a moving target, the corresponding pixels in the MVP image are shifting approximately regularly in time sequence. And the target trajectory is determined by Hough transform according to the pixel characteristics of the target and the clutter and noise. Comparing with traditional frame-by-frame methods, determining associated trajectories from MVP reduces the computation load. Numerical simulations are presented to demonstrate the effectiveness of the approach proposed.

Utilization of cone-beam CT for offline evaluation of target volume coverage during prostate image-guided radiotherapy based on bony anatomy alignment.

PubMed

Paluska, Petr; Hanus, Josef; Sefrova, Jana; Rouskova, Lucie; Grepl, Jakub; Jansa, Jan; Kasaova, Linda; Hodek, Miroslav; Zouhar, Milan; Vosmik, Milan; Petera, Jiri

2012-01-01

To assess target volume coverage during prostate image-guided radiotherapy based on bony anatomy alignment and to assess possibility of safety margin reduction. Implementation of IGRT should influence safety margins. Utilization of cone-beam CT provides current 3D anatomic information directly in irradiation position. Such information enables reconstruction of the actual dose distribution. Seventeen prostate patients were treated with daily bony anatomy image-guidance. Cone-beam CT (CBCT) scans were acquired once a week immediately after bony anatomy alignment. After the prostate, seminal vesicles, rectum and bladder were contoured, the delivered dose distribution was reconstructed. Target dose coverage was evaluated by the proportion of the CTV encompassed by the 95% isodose. Original plans employed a 1 cm safety margin. Alternative plans assuming a smaller 7 mm margin between CTV and PTV were evaluated in the same way. Rectal and bladder volumes were compared with the initial ones. Rectal and bladder volumes irradiated with doses higher than 75 Gy, 70 Gy, 60 Gy, 50 Gy and 40 Gy were analyzed. In 12% of reconstructed plans the prostate coverage was not sufficient. The prostate underdosage was observed in 5 patients. Coverage of seminal vesicles was not satisfactory in 3% of plans. Most of the target underdosage corresponded to excessive rectal or bladder filling. Evaluation of alternative plans assuming a smaller 7 mm margin revealed 22% and 11% of plans where prostate and seminal vesicles coverage, respectively, was compromised. These were distributed over 8 and 7 patients, respectively. Sufficient dose coverage of target volumes was not achieved for all patients. Reducing of safety margin is not acceptable. Initial rectal and bladder volumes cannot be considered representative for subsequent treatment.

Miniature Laser Tracker

DOEpatents

Vann, Charles S.

2003-09-09

This small, inexpensive, non-contact laser sensor can detect the location of a retroreflective target in a relatively large volume and up to six degrees of position. The tracker's laser beam is formed into a plane of light which is swept across the space of interest. When the beam illuminates the retroreflector, some of the light returns to the tracker. The intensity, angle, and time of the return beam is measured to calculate the three dimensional location of the target. With three retroreflectors on the target, the locations of three points on the target are measured, enabling the calculation of all six degrees of target position. Until now, devices for three-dimensional tracking of objects in a large volume have been heavy, large, and very expensive. Because of the simplicity and unique characteristics of this tracker, it is capable of three-dimensional tracking of one to several objects in a large volume, yet it is compact, light-weight, and relatively inexpensive. Alternatively, a tracker produces a diverging laser beam which is directed towards a fixed position, and senses when a retroreflective target enters the fixed field of view. An optically bar coded target can be read by the tracker to provide information about the target. The target can be formed of a ball lens with a bar code on one end. As the target moves through the field, the ball lens causes the laser beam to scan across the bar code.

ON THE BENEFITS AND RISKS OF PROTON THERAPY IN PEDIATRIC CRANIOPHARYNGIOMA

PubMed Central

Beltran, Chris; Roca, Monica; Merchant, Thomas E.

2013-01-01

Purpose Craniopharyngioma is a pediatric brain tumor whose volume is prone to change during radiation therapy. We compared photon- and proton-based irradiation methods to determine the effect of tumor volume change on target coverage and normal tissue irradiation in these patients. Methods and Materials For this retrospective study, we acquired imaging and treatment-planning data from 14 children with craniopharyngioma (mean age, 5.1 years) irradiated with photons (54 Gy) and monitored by weekly magnetic resonance imaging (MRI) examinations during radiation therapy. Photon intensity-modulated radiation therapy (IMRT), double-scatter proton (DSP) therapy, and intensity-modulated proton therapy (IMPT) plans were created for each patient based on his or her pre-irradiation MRI. Target volumes were contoured on each weekly MRI scan for adaptive modeling. The measured differences in conformity index (CI) and normal tissue doses, including functional sub-volumes of the brain, were compared across the planning methods, as was target coverage based on changes in target volumes during treatment. Results CI and normal tissue dose values of IMPT plans were significantly better than those of the IMRT and DSP plans (p < 0.01). Although IMRT plans had a higher CI and lower optic nerve doses (p < 0.01) than did DSP plans, DSP plans had lower cochlear, optic chiasm, brain, and scanned body doses (p < 0.01). The mean planning target volume (PTV) at baseline was 54.8 cm3, and the mean increase in PTV was 11.3% over the course of treatment. The dose to 95% of the PTV was correlated with a change in the PTV; the R2 values for all models, 0.73 (IMRT), 0.38 (DSP), and 0.62 (IMPT), were significant (p < 0.01). Conclusions Compared with photon IMRT, proton therapy has the potential to significantly reduce whole-brain and -body irradiation in pediatric patients with craniopharyngioma. IMPT is the most conformal method and spares the most normal tissue; however, it is highly sensitive to target volume changes, whereas the DSP method is not. PMID:21570209

Interobserver delineation uncertainty in involved-node radiation therapy (INRT) for early-stage Hodgkin lymphoma: on behalf of the Radiotherapy Committee of the EORTC lymphoma group.

PubMed

Aznar, Marianne C; Girinsky, Theodore; Berthelsen, Anne Kiil; Aleman, Berthe; Beijert, Max; Hutchings, Martin; Lievens, Yolande; Meijnders, Paul; Meidahl Petersen, Peter; Schut, Deborah; Maraldo, Maja V; van der Maazen, Richard; Specht, Lena

2017-04-01

In early-stage classical Hodgkin lymphoma (HL) the target volume nowadays consists of the volume of the originally involved nodes. Delineation of this volume on a post-chemotherapy CT-scan is challenging. We report on the interobserver variability in target volume definition and its impact on resulting treatment plans. Two representative cases were selected (1: male, stage IB, localization: left axilla; 2: female, stage IIB, localizations: mediastinum and bilateral neck). Eight experienced observers individually defined the clinical target volume (CTV) using involved-node radiotherapy (INRT) as defined by the EORTC-GELA guidelines for the H10 trial. A consensus contour was generated and the standard deviation computed. We investigated the overlap between observer and consensus contour [Sørensen-Dice coefficient (DSC)] and the magnitude of gross deviations between the surfaces of the observer and consensus contour (Hausdorff distance). 3D-conformal (3D-CRT) and intensity-modulated radiotherapy (IMRT) plans were calculated for each contour in order to investigate the impact of interobserver variability on each treatment modality. Similar target coverage was enforced for all plans. The median CTV was 120 cm 3 (IQR: 95-173 cm 3 ) for Case 1, and 255 cm 3 (IQR: 183-293 cm 3 ) for Case 2. DSC values were generally high (>0.7), and Hausdorff distances were about 30 mm. The SDs between all observer contours, providing an estimate of the systematic error associated with delineation uncertainty, ranged from 1.9 to 3.8 mm (median: 3.2 mm). Variations in mean dose resulting from different observer contours were small and were not higher in IMRT plans than in 3D-CRT plans. We observed considerable differences in target volume delineation, but the systematic delineation uncertainty of around 3 mm is comparable to that reported in other tumour sites. This report is a first step towards calculating an evidence-based planning target volume margin for INRT in HL.

Virtual medicinal chemistry: in silico pre-docking functional group transformation for discovery of novel inhibitors of botulinum toxin serotype A light chain.

PubMed

O'Malley, Sean; Sareth, Sina; Jiao, Guan-Sheng; Kim, Seongjin; Thai, April; Cregar-Hernandez, Lynne; McKasson, Linda; Margosiak, Stephen A; Johnson, Alan T

2013-05-01

A novel method for applying high-throughput docking to challenging metalloenzyme targets is described. The method utilizes information-based virtual transformation of library carboxylates to hydroxamic acids prior to docking, followed by compound acquisition, one-pot (two steps) chemical synthesis and in vitro screening. In two experiments targeting the botulinum neurotoxin serotype A metalloprotease light chain, hit rates of 32% and 18% were observed. Copyright © 2013 Elsevier Ltd. All rights reserved.

Assessment of the derivative-moment transformation method for unsteady-load estimation

NASA Astrophysics Data System (ADS)

Mohebbian, Ali; Rival, David E.

2012-08-01

It is often difficult, if not impossible, to measure the aerodynamic or hydrodynamic forces on a moving body. For this reason, a classical control-volume technique is typically applied to extract the unsteady forces. However, measuring the acceleration term within the volume of interest using particle image velocimetry (PIV) can be limited by optical access, reflections, as well as shadows. Therefore, in this study, an alternative approach, termed the derivative-moment transformation (DMT) method, is introduced and tested on a synthetic data set produced using numerical simulations. The test case involves the unsteady loading of a flat plate in a two-dimensional, laminar periodic gust. The results suggest that the DMT method can accurately predict the acceleration term so long as appropriate spatial and temporal resolutions are maintained. The major deficiency, which is more dominant for the direction of drag, was found to be the determination of pressure and unsteady terms in the wake. The effect of control-volume size was investigated, suggesting that larger domains work best by minimizing the associated error in the determination of the pressure field. When decreasing the control-volume size, wake vortices, which produce high gradients across the control surfaces, are found to substantially increase the level of error. On the other hand, it was shown that for large control volumes, and with realistic spatial resolution, the accuracy of the DMT method would also suffer. Therefore, a delicate compromise is required when selecting control-volume size in future experiments.

Detection and Classification of Transformer Winding Mechanical Faults Using UWB Sensors and Bayesian Classifier

NASA Astrophysics Data System (ADS)

Alehosseini, Ali; A. Hejazi, Maryam; Mokhtari, Ghassem; B. Gharehpetian, Gevork; Mohammadi, Mohammad

2015-06-01

In this paper, the Bayesian classifier is used to detect and classify the radial deformation and axial displacement of transformer windings. The proposed method is tested on a model of transformer for different volumes of radial deformation and axial displacement. In this method, ultra-wideband (UWB) signal is sent to the simplified model of the transformer winding. The received signal from the winding model is recorded and used for training and testing of Bayesian classifier in different axial displacement and radial deformation states of the winding. It is shown that the proposed method has a good accuracy to detect and classify the axial displacement and radial deformation of the winding.

Development of a carburizing and quenching simulation tool: A material model for low carbon steels undergoing phase transformations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bammann, D.; Prantil, V.; Kumar, A.

1996-06-24

An internal state variable formulation for phase transforming alloy steels is presented. We have illustrated how local transformation plasticity can be accommodated by an appropriate choice for the corresponding internal stress field acting between the phases. The state variable framework compares well with a numerical micromechanical calculation providing a discrete dependence of microscopic plasticity on volume fraction and the stress dependence attributable to a softer parent phase. The multiphase model is used to simulate the stress state of a quenched bar and show qualitative trends in the response when the transformation phenomenon is incorporated on the length scale of amore » global boundary value problem.« less

Maize transformation technology development for commercial event generation.

PubMed

Que, Qiudeng; Elumalai, Sivamani; Li, Xianggan; Zhong, Heng; Nalapalli, Samson; Schweiner, Michael; Fei, Xiaoyin; Nuccio, Michael; Kelliher, Timothy; Gu, Weining; Chen, Zhongying; Chilton, Mary-Dell M

2014-01-01

Maize is an important food and feed crop in many countries. It is also one of the most important target crops for the application of biotechnology. Currently, there are more biotech traits available on the market in maize than in any other crop. Generation of transgenic events is a crucial step in the development of biotech traits. For commercial applications, a high throughput transformation system producing a large number of high quality events in an elite genetic background is highly desirable. There has been tremendous progress in Agrobacterium-mediated maize transformation since the publication of the Ishida et al. (1996) paper and the technology has been widely adopted for transgenic event production by many labs around the world. We will review general efforts in establishing efficient maize transformation technologies useful for transgenic event production in trait research and development. The review will also discuss transformation systems used for generating commercial maize trait events currently on the market. As the number of traits is increasing steadily and two or more modes of action are used to control key pests, new tools are needed to efficiently transform vectors containing multiple trait genes. We will review general guidelines for assembling binary vectors for commercial transformation. Approaches to increase transformation efficiency and gene expression of large gene stack vectors will be discussed. Finally, recent studies of targeted genome modification and transgene insertion using different site-directed nuclease technologies will be reviewed.

Maize transformation technology development for commercial event generation

PubMed Central

Que, Qiudeng; Elumalai, Sivamani; Li, Xianggan; Zhong, Heng; Nalapalli, Samson; Schweiner, Michael; Fei, Xiaoyin; Nuccio, Michael; Kelliher, Timothy; Gu, Weining; Chen, Zhongying; Chilton, Mary-Dell M.

2014-01-01

Maize is an important food and feed crop in many countries. It is also one of the most important target crops for the application of biotechnology. Currently, there are more biotech traits available on the market in maize than in any other crop. Generation of transgenic events is a crucial step in the development of biotech traits. For commercial applications, a high throughput transformation system producing a large number of high quality events in an elite genetic background is highly desirable. There has been tremendous progress in Agrobacterium-mediated maize transformation since the publication of the Ishida et al. (1996) paper and the technology has been widely adopted for transgenic event production by many labs around the world. We will review general efforts in establishing efficient maize transformation technologies useful for transgenic event production in trait research and development. The review will also discuss transformation systems used for generating commercial maize trait events currently on the market. As the number of traits is increasing steadily and two or more modes of action are used to control key pests, new tools are needed to efficiently transform vectors containing multiple trait genes. We will review general guidelines for assembling binary vectors for commercial transformation. Approaches to increase transformation efficiency and gene expression of large gene stack vectors will be discussed. Finally, recent studies of targeted genome modification and transgene insertion using different site-directed nuclease technologies will be reviewed. PMID:25140170

Study and Experiment on Non-Contact Voltage Sensor Suitable for Three-Phase Transmission Line

PubMed Central

Zhou, Qiang; He, Wei; Xiao, Dongping; Li, Songnong; Zhou, Kongjun

2015-01-01

A voltage transformer, as voltage signal detection equipment, plays an important role in a power system. Presently, more and more electric power systems are adopting potential transformer and capacitance voltage transformers. Transformers are often large in volume and heavyweight, their insulation design is difficult, and an iron core or multi-grade capacitance voltage division structure is generally adopted. As a result, the detection accuracy of transformer is reduced, a huge phase difference exists between detection signal and voltage signal to be measured, and the detection signal cannot accurately and timely reflect the change of conductor voltage signal to be measured. By aiming at the current problems of electric transformation, based on electrostatic induction principle, this paper designed a non-contact voltage sensor and gained detection signal of the sensor through electrostatic coupling for the electric field generated by electric charges of the conductor to be measured. The insulation structure design of the sensor is simple and its volume is small; phase difference of sensor measurement is effectively reduced through optimization design of the electrode; and voltage division ratio and measurement accuracy are increased. The voltage sensor was tested on the experimental platform of simulating three-phase transmission line. According to the result, the designed non-contact voltage sensor can realize accurate and real-time measurement for the conductor voltage. It can be applied to online monitoring for the voltage of three-phase transmission line or three-phase distribution network line, which is in accordance with the development direction of the smart grid. PMID:26729119

Study and Experiment on Non-Contact Voltage Sensor Suitable for Three-Phase Transmission Line.

PubMed

Zhou, Qiang; He, Wei; Xiao, Dongping; Li, Songnong; Zhou, Kongjun

2015-12-30

A voltage transformer, as voltage signal detection equipment, plays an important role in a power system. Presently, more and more electric power systems are adopting potential transformer and capacitance voltage transformers. Transformers are often large in volume and heavyweight, their insulation design is difficult, and an iron core or multi-grade capacitance voltage division structure is generally adopted. As a result, the detection accuracy of transformer is reduced, a huge phase difference exists between detection signal and voltage signal to be measured, and the detection signal cannot accurately and timely reflect the change of conductor voltage signal to be measured. By aiming at the current problems of electric transformation, based on electrostatic induction principle, this paper designed a non-contact voltage sensor and gained detection signal of the sensor through electrostatic coupling for the electric field generated by electric charges of the conductor to be measured. The insulation structure design of the sensor is simple and its volume is small; phase difference of sensor measurement is effectively reduced through optimization design of the electrode; and voltage division ratio and measurement accuracy are increased. The voltage sensor was tested on the experimental platform of simulating three-phase transmission line. According to the result, the designed non-contact voltage sensor can realize accurate and real-time measurement for the conductor voltage. It can be applied to online monitoring for the voltage of three-phase transmission line or three-phase distribution network line, which is in accordance with the development direction of the smart grid.

Analysis of FET-PET imaging for target volume definition in patients with gliomas treated with conformal radiotherapy.

PubMed

Rieken, Stefan; Habermehl, Daniel; Giesel, Frederik L; Hoffmann, Christoph; Burger, Ute; Rief, Harald; Welzel, Thomas; Haberkorn, Uwe; Debus, Jürgen; Combs, Stephanie E

2013-12-01

Modern radiotherapy (RT) techniques such as stereotactic RT, intensity-modulated RT, or particle irradiation allow local dose escalation with simultaneous sparing of critical organs. Several trials are currently investigating their benefit in glioma reirradiation and boost irradiation. Target volume definition is of critical importance especially when steep dose gradient techniques are employed. In this manuscript we investigate the impact of O-(2-(F-18)fluoroethyl)-l-tyrosine-positron emission tomography/computer tomography (FET-PET/CT) on target volume definition in low and high grade glioma patients undergoing either first or re-irradiation with particles. We investigated volumetric size and uniformity of magnetic resonance imaging (MRI)- vs. FET-PET/CT-derived gross tumor volumes (GTVs) and planning target volumes (PTVs) of 41 glioma patients. Clinical cases are presented to demonstrate potential benefits of integrating FET-PET/CT-planning into daily routine. Integrating FET-uptake into the delineation of GTVs yields larger volumes. Combined modality-derived PTVs are significantly enlarged in high grade glioma patients and in case of primary RT. The congruence of MRI and FET signals for the identification of glioma GTVs is poor with mean uniformity indices of 0.39. MRI-based PTVs miss 17% of FET-PET/CT-based GTVs. Non significant alterations were detected in low grade glioma patients and in those undergoing reirradiation. Target volume definition for malignant gliomas during initial RT may yield significantly differing results depending upon the imaging modality, which the contouring process is based upon. The integration of both MRI and FET-PET/CT may help to improve GTV coverage by avoiding larger incongruences between physical and biological imaging techniques. In low grade gliomas and in cases of reirradiation, more studies are needed in order to investigate a potential benefit of FET-PET/CT for planning of RT. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Dosimetric and radiobiological characterizations of prostate intensity-modulated radiotherapy and volumetric-modulated arc therapy: A single-institution review of ninety cases

PubMed Central

Khan, Muhammad Isa; Jiang, Runqing; Kiciak, Alexander; ur Rehman, Jalil; Afzal, Muhammad; Chow, James C. L.

2016-01-01

This study reviewed prostate volumetric-modulated arc therapy (VMAT) plans with intensity-modulated radiotherapy (IMRT) plans after prostate IMRT technique was replaced by VMAT in an institution. Characterizations of dosimetry and radiobiological variation in prostate were determined based on treatment plans of 40 prostate IMRT patients (planning target volume = 77.8–335 cm3) and 50 VMAT patients (planning target volume = 120–351 cm3) treated before and after 2013, respectively. Both IMRT and VMAT plans used the same dose-volume criteria in the inverse planning optimization. Dose-volume histogram, mean doses of target and normal tissues (rectum, bladder and femoral heads), dose-volume points (D99% of planning target volume; D30%, D50%, V30 Gy and V35 Gy of rectum and bladder; D5%, V14 Gy, V22 Gy of femoral heads), conformity index (CI), homogeneity index (HI), gradient index (GI), prostate tumor control probability (TCP), and rectal normal tissue complication probability (NTCP) based on the Lyman-Burman-Kutcher algorithm were calculated for each IMRT and VMAT plan. From our results, VMAT plan was found better due to its higher (1.05%) CI, lower (0.83%) HI and (0.75%) GI than IMRT. Comparing doses in normal tissues between IMRT and VMAT, it was found that IMRT mostly delivered higher doses of about 1.05% to the normal tissues than VMAT. Prostate TCP and rectal NTCP were found increased (1%) for VMAT than IMRT. It is seen that VMAT technique can decrease the dose-volume evaluation criteria for the normal tissues. Based on our dosimetric and radiobiological results in treatment plans, it is concluded that our VMAT implementation could produce comparable or slightly better target coverage and normal tissue sparing with a faster treatment time in prostate radiotherapy. PMID:27651562

Secret shared multiple-image encryption based on row scanning compressive ghost imaging and phase retrieval in the Fresnel domain

NASA Astrophysics Data System (ADS)

Li, Xianye; Meng, Xiangfeng; Wang, Yurong; Yang, Xiulun; Yin, Yongkai; Peng, Xiang; He, Wenqi; Dong, Guoyan; Chen, Hongyi

2017-09-01

A multiple-image encryption method is proposed that is based on row scanning compressive ghost imaging, (t, n) threshold secret sharing, and phase retrieval in the Fresnel domain. In the encryption process, after wavelet transform and Arnold transform of the target image, the ciphertext matrix can be first detected using a bucket detector. Based on a (t, n) threshold secret sharing algorithm, the measurement key used in the row scanning compressive ghost imaging can be decomposed and shared into two pairs of sub-keys, which are then reconstructed using two phase-only mask (POM) keys with fixed pixel values, placed in the input plane and transform plane 2 of the phase retrieval scheme, respectively; and the other POM key in the transform plane 1 can be generated and updated by the iterative encoding of each plaintext image. In each iteration, the target image acts as the input amplitude constraint in the input plane. During decryption, each plaintext image possessing all the correct keys can be successfully decrypted by measurement key regeneration, compression algorithm reconstruction, inverse wavelet transformation, and Fresnel transformation. Theoretical analysis and numerical simulations both verify the feasibility of the proposed method.

Altering the sex determination pathway in Drosophila fat body modifies sex-specific stress responses.

PubMed

Argue, Kathryn J; Neckameyer, Wendi S

2014-07-01

The stress response in Drosophila melanogaster reveals sex differences in behavior, similar to what has been observed in mammals. However, unlike mammals, the sex determination pathway in Drosophila is well established, making this an ideal system to identify factors involved in the modulation of sex-specific responses to stress. In this study, we show that the Drosophila fat body, which has been shown to be important for energy homeostasis and sex determination, is a dynamic tissue that is altered in response to stress in a sex and time-dependent manner. We manipulated the sex determination pathway in the fat body via targeted expression of transformer and transformer-2 and analyzed these animals for changes in their response to stress. In the majority of cases, manipulation of transformer or transformer-2 was able to change the physiological output in response to starvation and oxidative stress to that of the opposite sex. Our data also uncover the possibility of additional downstream targets for transformer and transformer-2 that are separate from the sex determination pathway and can influence behavioral and physiological responses. Copyright © 2014 the American Physiological Society.

ESTRO ACROP guidelines for target volume definition in the treatment of locally advanced non-small cell lung cancer.

PubMed

Nestle, Ursula; De Ruysscher, Dirk; Ricardi, Umberto; Geets, Xavier; Belderbos, Jose; Pöttgen, Christoph; Dziadiuszko, Rafal; Peeters, Stephanie; Lievens, Yolande; Hurkmans, Coen; Slotman, Ben; Ramella, Sara; Faivre-Finn, Corinne; McDonald, Fiona; Manapov, Farkhad; Putora, Paul Martin; LePéchoux, Cécile; Van Houtte, Paul

2018-04-01

Radiotherapy (RT) plays a major role in the curative treatment of locally advanced non-small cell lung cancer (NSCLC). Therefore, the ACROP committee was asked by the ESTRO to provide recommendations on target volume delineation for standard clinical scenarios in definitive (chemo)radiotherapy (RT) and adjuvant RT for locally advanced NSCLC. The guidelines given here are a result of the evaluation of a structured questionnaire followed by a consensus discussion, voting and writing procedure within the committee. Hence, we provide advice for methods and time-points of diagnostics and imaging before the start of treatment planning and for the mandatory and optional imaging to be used for planning itself. Concerning target volumes, recommendations are given for GTV delineation of primary tumour and lymph nodes followed by issues related to the delineation of CTVs for definitive and adjuvant radiotherapy. In the context of PTV delineation, recommendations about the management of geometric uncertainties and target motion are given. We further provide our opinions on normal tissue delineation and organisational and responsibility questions in the process of target volume delineation. This guideline intends to contribute to the standardisation and optimisation of the process of RT treatment planning for clinical practice and prospective studies. Copyright © 2018 Elsevier B.V. All rights reserved.

Clinical implementation of stereotaxic brain implant optimization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rosenow, U.F.; Wojcicka, J.B.

1991-03-01

This optimization method for stereotaxic brain implants is based on seed/strand configurations of the basic type developed for the National Cancer Institute (NCI) atlas of regular brain implants. Irregular target volume shapes are determined from delineation in a stack of contrast enhanced computed tomography scans. The neurosurgeon may then select up to ten directions, or entry points, of surgical approach of which the program finds the optimal one under the criterion of smallest target volume diameter. Target volume cross sections are then reconstructed in 5-mm-spaced planes perpendicular to the implantation direction defined by the entry point and the target volumemore » center. This information is used to define a closed line in an implant cross section along which peripheral seed strands are positioned and which has now an irregular shape. Optimization points are defined opposite peripheral seeds on the target volume surface to which the treatment dose rate is prescribed. Three different optimization algorithms are available: linear least-squares programming, quadratic programming with constraints, and a simplex method. The optimization routine is implemented into a commercial treatment planning system. It generates coordinate and source strength information of the optimized seed configurations for further dose rate distribution calculation with the treatment planning system, and also the coordinate settings for the stereotaxic Brown-Roberts-Wells (BRW) implantation device.« less

Target coverage in image-guided stereotactic body radiotherapy of liver tumors.

PubMed

Wunderink, Wouter; Méndez Romero, Alejandra; Vásquez Osorio, Eliana M; de Boer, Hans C J; Brandwijk, René P; Levendag, Peter C; Heijmen, Ben J M

2007-05-01

To determine the effect of image-guided procedures (with computed tomography [CT] and electronic portal images before each treatment fraction) on target coverage in stereotactic body radiotherapy for liver patients using a stereotactic body frame (SBF) and abdominal compression. CT guidance was used to correct for day-to-day variations in the tumor's mean position in the SBF. By retrospectively evaluating 57 treatment sessions, tumor coverage, as obtained with the clinically applied CT-guided protocol, was compared with that of alternative procedures. The internal target volume-plus (ITV(+)) was introduced to explicitly include uncertainties in tumor delineations resulting from CT-imaging artifacts caused by residual respiratory motion. Tumor coverage was defined as the volume overlap of the ITV(+), derived from a tumor delineated in a treatment CT scan, and the planning target volume. Patient stability in the SBF, after acquisition of the treatment CT scan, was evaluated by measuring the displacement of the bony anatomy in the electronic portal images relative to CT. Application of our clinical protocol (with setup corrections following from manual measurements of the distances between the contours of the planning target volume and the daily clinical target volume in three orthogonal planes, multiple two-dimensional) increased the frequency of nearly full (> or = 99%) ITV(+) coverage to 77% compared with 63% without setup correction. An automated three-dimensional method further improved the frequency to 96%. Patient displacements in the SBF were generally small (< or = 2 mm, 1 standard deviation), but large craniocaudal displacements (maximal 7.2 mm) were occasionally observed. Daily, CT-assisted patient setup may substantially improve tumor coverage, especially with the automated three-dimensional procedure. In the present treatment design, patient stability in the SBF should be verified with portal imaging.

Preoperative single fraction partial breast radiotherapy for early-stage breast cancer.

PubMed

Palta, Manisha; Yoo, Sua; Adamson, Justus D; Prosnitz, Leonard R; Horton, Janet K

2012-01-01

Several recent series evaluating external beam accelerated partial breast irradiation (PBI) have reported adverse cosmetic outcomes, possibly related to large volumes of normal tissue receiving near-prescription doses. We hypothesized that delivery of external beam PBI in a single fraction to the preoperative tumor volume would be feasible and result in a decreased dose to the uninvolved breast compared with institutional postoperative PBI historical controls. A total of 17 patients with unifocal Stage T1 breast cancer were identified. Contrast-enhanced subtraction magnetic resonance images were loaded into an Eclipse treatment planning system and used to define the target volumes. A "virtual plan" was created using four photon beams in a noncoplanar beam arrangement and optimized to deliver 15 Gy to the planning target volume. The median breast volume was 1,713 cm(3) (range: 1,014-2,140), and the median clinical target volume was 44 cm(3) (range: 26-73). In all cases, 100% of the prescription dose covered 95% of the clinical target volume. The median conformity index was 0.86 (range: 0.70-1.12). The median percentage of the ipsilateral breast volume receiving 100% and 50% of the prescribed dose was 3.8% (range: 2.2-6.9) and 13.3% (range: 7.5-20.8) compared with 18% (range: 3-42) and 53% (range: 24-65) in the institutional historical controls treated with postoperative external beam PBI (p = .002). The median maximum skin dose was 9 Gy. The median dose to 1 and 10 cm(3) of skin was 6.7 and 4.9 Gy. The doses to the heart and ipsilateral lung were negligible. Preoperative PBI resulted in a substantial reduction in ipsilateral breast tissue dose compared with postoperative PBI. The skin dose appeared reasonable, given the small volumes. A prospective Phase I trial evaluating this technique is ongoing. Copyright © 2012 Elsevier Inc. All rights reserved.

Genetic transformation of Fusarium avenaceum by Agrobacterium tumefaciens mediated transformation and the development of a USER-Brick vector construction system

PubMed Central

2014-01-01

Background The plant pathogenic and saprophytic fungus Fusarium avenaceum causes considerable in-field and post-field losses worldwide due to its infections of a wide range of different crops. Despite its significant impact on the profitability of agriculture production and a desire to characterize the infection process at the molecular biological level, no genetic transformation protocol has yet been established for F. avenaceum. In the current study, it is shown that F. avenaceum can be efficiently transformed by Agrobacterium tumefaciens mediated transformation. In addition, an efficient and versatile single step vector construction strategy relying on Uracil Specific Excision Reagent (USER) Fusion cloning, is developed. Results The new vector construction system, termed USER-Brick, is based on a limited number of PCR amplified vector fragments (core USER-Bricks) which are combined with PCR generated fragments from the gene of interest. The system was found to have an assembly efficiency of 97% with up to six DNA fragments, based on the construction of 55 vectors targeting different polyketide synthase (PKS) and PKS associated transcription factor encoding genes in F. avenaceum. Subsequently, the ΔFaPKS3 vector was used for optimizing A. tumefaciens mediated transformation (ATMT) of F. avenaceum with respect to six variables. Acetosyringone concentration, co-culturing time, co-culturing temperature and fungal inoculum were found to significantly impact the transformation frequency. Following optimization, an average of 140 transformants per 106 macroconidia was obtained in experiments aimed at introducing targeted genome modifications. Targeted deletion of FaPKS6 (FA08709.2) in F. avenaceum showed that this gene is essential for biosynthesis of the polyketide/nonribosomal compound fusaristatin A. Conclusion The new USER-Brick system is highly versatile by allowing for the reuse of a common set of building blocks to accommodate seven different types of genome modifications. New USER-Bricks with additional functionality can easily be added to the system by future users. The optimized protocol for ATMT of F. avenaceum represents the first reported targeted genome modification by double homologous recombination of this plant pathogen and will allow for future characterization of this fungus. Functional linkage of FaPKS6 to the production of the mycotoxin fusaristatin A serves as a first testimony to this. PMID:25048842

Converting Differential Photometry Results to the Standard System using Transform Generator and Transform Applier (Abstract)

NASA Astrophysics Data System (ADS)

Ciocca, M.

2016-12-01

(Abstract only) Since Fall of 2014, AAVSO made available two very useful software tools: transform generator (tg) and transform applier (ta). tg, authored by Gordon Myers (gordonmyers@hotmail.com), is a program, running under python that allows the user to obtain the transformation coefficients of their imaging train. ta, authored by George Silvis, allows users to apply the transformation coefficients obtained previously to their photometric observation. The data so processed become then directly comparable to those of other observers. I will show how to obtain transform coefficient using two Standard Field (M 67 and NGC7790), how consistent the results are and as an application, I will present transformed data for two AAVSO Target stars, AE UMA and RR CET.

Semi-automated segmentation of a glioblastoma multiforme on brain MR images for radiotherapy planning.

PubMed

Hori, Daisuke; Katsuragawa, Shigehiko; Murakami, Ryuuji; Hirai, Toshinori

2010-04-20

We propose a computerized method for semi-automated segmentation of the gross tumor volume (GTV) of a glioblastoma multiforme (GBM) on brain MR images for radiotherapy planning (RTP). Three-dimensional (3D) MR images of 28 cases with a GBM were used in this study. First, a sphere volume of interest (VOI) including the GBM was selected by clicking a part of the GBM region in the 3D image. Then, the sphere VOI was transformed to a two-dimensional (2D) image by use of a spiral-scanning technique. We employed active contour models (ACM) to delineate an optimal outline of the GBM in the transformed 2D image. After inverse transform of the optimal outline to the 3D space, a morphological filter was applied to smooth the shape of the 3D segmented region. For evaluation of our computerized method, we compared the computer output with manually segmented regions, which were obtained by a therapeutic radiologist using a manual tracking method. In evaluating our segmentation method, we employed the Jaccard similarity coefficient (JSC) and the true segmentation coefficient (TSC) in volumes between the computer output and the manually segmented region. The mean and standard deviation of JSC and TSC were 74.2+/-9.8% and 84.1+/-7.1%, respectively. Our segmentation method provided a relatively accurate outline for GBM and would be useful for radiotherapy planning.

Individualized Nonadaptive and Online-Adaptive Intensity-Modulated Radiotherapy Treatment Strategies for Cervical Cancer Patients Based on Pretreatment Acquired Variable Bladder Filling Computed Tomography Scans

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bondar, M.L., E-mail: m.bondar@erasmusmc.nl; Hoogeman, M.S.; Mens, J.W.

2012-08-01

Purpose: To design and evaluate individualized nonadaptive and online-adaptive strategies based on a pretreatment established motion model for the highly deformable target volume in cervical cancer patients. Methods and Materials: For 14 patients, nine to ten variable bladder filling computed tomography (CT) scans were acquired at pretreatment and after 40 Gy. Individualized model-based internal target volumes (mbITVs) accounting for the cervix and uterus motion due to bladder volume changes were generated by using a motion-model constructed from two pretreatment CT scans (full and empty bladder). Two individualized strategies were designed: a nonadaptive strategy, using an mbITV accounting for the full-rangemore » of bladder volume changes throughout the treatment; and an online-adaptive strategy, using mbITVs of bladder volume subranges to construct a library of plans. The latter adapts the treatment online by selecting the plan-of-the-day from the library based on the measured bladder volume. The individualized strategies were evaluated by the seven to eight CT scans not used for mbITVs construction, and compared with a population-based approach. Geometric uniform margins around planning cervix-uterus and mbITVs were determined to ensure adequate coverage. For each strategy, the percentage of the cervix-uterus, bladder, and rectum volumes inside the planning target volume (PTV), and the clinical target volume (CTV)-to-PTV volume (volume difference between PTV and CTV) were calculated. Results: The margin for the population-based approach was 38 mm and for the individualized strategies was 7 to 10 mm. Compared with the population-based approach, the individualized nonadaptive strategy decreased the CTV-to-PTV volume by 48% {+-} 6% and the percentage of bladder and rectum inside the PTV by 5% to 45% and 26% to 74% (p < 0.001), respectively. Replacing the individualized nonadaptive strategy by an online-adaptive, two-plan library further decreased the percentage of bladder and rectum inside the PTV (0% to 10% and -1% to 9%; p < 0.004) and the CTV-to-PTV volume (4-96 ml). Conclusions: Compared with population-based margins, an individualized PTV results in better organ-at-risk sparing. Online-adaptive radiotherapy further improves organ-at-risk sparing.« less

Mitochondrial clearance by the STK38 kinase supports oncogenic Ras-induced cell transformation

PubMed Central

Bettoun, Audrey; Surdez, Didier; Vallerand, David; Gundogdu, Ramazan; Sharif, Ahmad A.D.; Gomez, Marta; Cascone, Ilaria; Meunier, Brigitte; White, Michael A.; Codogno, Patrice; Parrini, Maria Carla; Camonis, Jacques H.; Hergovich, Alexander

2016-01-01

Oncogenic Ras signalling occurs frequently in many human cancers. However, no effective targeted therapies are currently available to treat patients suffering from Ras-driven tumours. Therefore, it is imperative to identify downstream effectors of Ras signalling that potentially represent promising new therapeutic options. Particularly, considering that autophagy inhibition can impair the survival of Ras-transformed cells in tissue culture and mouse models, an understanding of factors regulating the balance between autophagy and apoptosis in Ras-transformed human cells is needed. Here, we report critical roles of the STK38 protein kinase in oncogenic Ras transformation. STK38 knockdown impaired anoikis resistance, anchorage-independent soft agar growth, and in vivo xenograft growth of Ras-transformed human cells. Mechanistically, STK38 supports Ras-driven transformation through promoting detachment-induced autophagy. Even more importantly, upon cell detachment STK38 is required to sustain the removal of damaged mitochondria by mitophagy, a selective autophagic process, to prevent excessive mitochondrial reactive oxygen species production that can negatively affect cancer cell survival. Significantly, knockdown of PINK1 or Parkin, two positive regulators of mitophagy, also impaired anoikis resistance and anchorage-independent growth of Ras-transformed human cells, while knockdown of USP30, a negative regulator of PINK1/Parkin-mediated mitophagy, restored anchorage-independent growth of STK38-depleted Ras-transformed human cells. Therefore, our findings collectively reveal novel molecular players that determine whether Ras-transformed human cells die or survive upon cell detachment, which potentially could be exploited for the development of novel strategies to target Ras-transformed cells. PMID:27283898

Employing Extracellular Volume Cardiovascular Magnetic Resonance Measures of Myocardial Fibrosis to Foster Novel Therapeutics.

PubMed

Schelbert, Erik B; Sabbah, Hani N; Butler, Javed; Gheorghiade, Mihai

2017-06-01

Quantifying myocardial fibrosis (MF) with myocardial extracellular volume measures acquired during cardiovascular magnetic resonance promises to transform clinical care by advancing pathophysiologic understanding and fostering novel therapeutics. Extracellular volume quantifies MF by measuring the extracellular compartment depicted by the myocardial uptake of contrast relative to plasma. MF is a key domain of dysfunctional but viable myocardium among others (eg, microvascular dysfunction and cardiomyocyte/mitochondrial dysfunction). Although anatomically distinct, these domains may functionally interact. MF represents pathological remodeling in the heart associated with cardiac dysfunction and adverse outcomes likely mediated by interactions with the microvasculature and the cardiomyocyte. Reversal of MF improves key measures of cardiac dysfunction, so reversal of MF represents a likely mechanism for improved outcomes. Instead of characterizing the myocardium as homogenous tissue and using important yet still generic descriptors, such as thickness (hypertrophy) and function (diastolic or systolic), which lack mechanistic specificity, paradigms of cardiac disease have evolved to conceptualize myocardial disease and patient vulnerability based on the extent of disease involving its various compartments. Specifying myocardial compartmental involvement may then implicate cellular/molecular disease pathways for treatment and targeted pharmaceutical development and above all highlight the role of the cardiac-specific pathology in heart failure among myriad other changes in the heart and beyond. The cardiology community now requires phase 2 and 3 clinical trials to examine strategies for the regression/prevention of MF and eventually biomarkers to identify MF without reliance on cardiovascular magnetic resonance. It seems likely that efficacious antifibrotic therapy will improve outcomes, but definitive data are needed. © 2017 American Heart Association, Inc.

Image-based modeling of tumor shrinkage in head and neck radiation therapy1

PubMed Central

Chao, Ming; Xie, Yaoqin; Moros, Eduardo G.; Le, Quynh-Thu; Xing, Lei

2010-01-01

Purpose: Understanding the kinetics of tumor growth∕shrinkage represents a critical step in quantitative assessment of therapeutics and realization of adaptive radiation therapy. This article presents a novel framework for image-based modeling of tumor change and demonstrates its performance with synthetic images and clinical cases. Methods: Due to significant tumor tissue content changes, similarity-based models are not suitable for describing the process of tumor volume changes. Under the hypothesis that tissue features in a tumor volume or at the boundary region are partially preserved, the kinetic change was modeled in two steps: (1) Autodetection of homologous tissue features shared by two input images using the scale invariance feature transformation (SIFT) method; and (2) establishment of a voxel-to-voxel correspondence between the images for the remaining spatial points by interpolation. The correctness of the tissue feature correspondence was assured by a bidirectional association procedure, where SIFT features were mapped from template to target images and reversely. A series of digital phantom experiments and five head and neck clinical cases were used to assess the performance of the proposed technique. Results: The proposed technique can faithfully identify the known changes introduced when constructing the digital phantoms. The subsequent feature-guided thin plate spline calculation reproduced the “ground truth” with accuracy better than 1.5 mm. For the clinical cases, the new algorithm worked reliably for a volume change as large as 30%. Conclusions: An image-based tumor kinetic algorithm was developed to model the tumor response to radiation therapy. The technique provides a practical framework for future application in adaptive radiation therapy. PMID:20527569

Targeting RAS-driven human cancer cells with antibodies to upregulated and essential cell-surface proteins.

PubMed

Martinko, Alexander J; Truillet, Charles; Julien, Olivier; Diaz, Juan E; Horlbeck, Max A; Whiteley, Gordon; Blonder, Josip; Weissman, Jonathan S; Bandyopadhyay, Sourav; Evans, Michael J; Wells, James A

2018-01-23

While there have been tremendous efforts to target oncogenic RAS signaling from inside the cell, little effort has focused on the cell-surface. Here, we used quantitative surface proteomics to reveal a signature of proteins that are upregulated on cells transformed with KRAS G12V , and driven by MAPK pathway signaling. We next generated a toolkit of recombinant antibodies to seven of these RAS-induced proteins. We found that five of these proteins are broadly distributed on cancer cell lines harboring RAS mutations. In parallel, a cell-surface CRISPRi screen identified integrin and Wnt signaling proteins as critical to RAS-transformed cells. We show that antibodies targeting CDCP1, a protein common to our proteomics and CRISPRi datasets, can be leveraged to deliver cytotoxic and immunotherapeutic payloads to RAS-transformed cancer cells and report for RAS signaling status in vivo. Taken together, this work presents a technological platform for attacking RAS from outside the cell. © 2018, Martinko et al.

Next-Generation Performance-Based Regulation. Volume 1: Introduction - Global Lessons for Success; Volume 2: Primer - Essential Elements of Design and Implementation; Volume 3: Innovative Examples from Around the World

DOE Office of Scientific and Technical Information (OSTI.GOV)

Logan, Jeffrey S

Performance-based regulations (PBRs) provide a regulatory framework to connect goals, targets, and measures to utility performance or executive compensation. Well-designed PBRs provide incentives for utility performance, benefiting consumers and utility owners alike. This report considers the role of both PBRs and more discrete performance incentive mechanisms (PIMs) in 21st century power sector transformation. Innovative technologies are transforming the way electricity is generated, delivered, and consumed. PBRs have the potential to realign utility, investor, and consumer incentives and mitigate emerging challenges to the utility business model, renewable integration, and even cyber security.The goals of PBRs in the form of multi-year ratemore » plans are in many respects the same in terms of providing reasonably priced and reliable service to customers. However, today's technologies have changed, and there is more emphasis on clean energy. Thus, the pathways and the potential outcomes are different than they were in the 20th century when centralized generator stations and large infrastructure additions dominated the utility landscape. Given unprecedented changes underway in the electricity sector, PBRs - by specifying expectations of utility performance and outcomes for consumers, while staying agnostic to the exact means of delivery - constitute a form of prescient regulation that harnesses disruption. PBRs are one tool in a broader toolbox in the transition toward flexible regulatory and market structures that rewards utilities that adapt or evolve in reaction to market and technology change. PBRs and PIMs have great value for the electric industry when designed well and can be applied to many different situations. How exactly PBR mechanisms are most effectively enacted will vary based on the utility ownership model, institutional arrangements, and a variety of other local factors. PBRs should be tailored to the needs and goals of each jurisdiction, and perhaps each utility, to most effectively achieve the needs of a 21st century power grid in that jurisdiction. Presented in three volumes, this report highlights the lessons learned from their evolving history, explores essential elements of their design and implementation as well as considerations for how they may be best applied, and examines leading examples of PBRs from the United Kingdom, New York, Denmark, Mexico, and South Africa. The full report, 'Next-Generation Performance Based Regulation - Emphasizing Utility Performance to Unleash Power Sector Innovation,' published in September 2017, can be accessed at https://www.nrel.gov/docs/fy17osti/68512.pdf.« less

Fluence map optimization (FMO) with dose-volume constraints in IMRT using the geometric distance sorting method.

PubMed

Lan, Yihua; Li, Cunhua; Ren, Haozheng; Zhang, Yong; Min, Zhifang

2012-10-21

A new heuristic algorithm based on the so-called geometric distance sorting technique is proposed for solving the fluence map optimization with dose-volume constraints which is one of the most essential tasks for inverse planning in IMRT. The framework of the proposed method is basically an iterative process which begins with a simple linear constrained quadratic optimization model without considering any dose-volume constraints, and then the dose constraints for the voxels violating the dose-volume constraints are gradually added into the quadratic optimization model step by step until all the dose-volume constraints are satisfied. In each iteration step, an interior point method is adopted to solve each new linear constrained quadratic programming. For choosing the proper candidate voxels for the current dose constraint adding, a so-called geometric distance defined in the transformed standard quadratic form of the fluence map optimization model was used to guide the selection of the voxels. The new geometric distance sorting technique can mostly reduce the unexpected increase of the objective function value caused inevitably by the constraint adding. It can be regarded as an upgrading to the traditional dose sorting technique. The geometry explanation for the proposed method is also given and a proposition is proved to support our heuristic idea. In addition, a smart constraint adding/deleting strategy is designed to ensure a stable iteration convergence. The new algorithm is tested on four cases including head-neck, a prostate, a lung and an oropharyngeal, and compared with the algorithm based on the traditional dose sorting technique. Experimental results showed that the proposed method is more suitable for guiding the selection of new constraints than the traditional dose sorting method, especially for the cases whose target regions are in non-convex shapes. It is a more efficient optimization technique to some extent for choosing constraints than the dose sorting method. By integrating a smart constraint adding/deleting scheme within the iteration framework, the new technique builds up an improved algorithm for solving the fluence map optimization with dose-volume constraints.

Dosimetric evaluation of IMRT plan for homogenous and inhomogeneous medium using AAPM TG-119 protocol

NASA Astrophysics Data System (ADS)

Fatimah, L. A. N.; Wibowo, W. E.; Pawiro, S. A.

2017-05-01

The American Association of Physicists in Medicine (AAPM) TG-119 protocol has been applied for dose verification in IMRT technique. However, some criteria in the protocol need to be verified for inhomogeneous medium and small volume targets. Hence, the purpose of this study was to verify the assessment criteria of dose verification in AAPM TG-119 for inhomogeneous medium and small volume targets. The work has been conducted by dose verification for homogeneous (phantom A) and inhomogeneous phantoms (phantom B and C) on two geometrical targets: C-shape and circular targets. The targets were simulated using 7 static dMLC IMRT fields at two different depths of 5 g/cm2 and 10 g/cm2. The dose optimisation and calculation were done by using Pinnacle3 for 6 MV photons beam. The planning objectives were set according to AAPM TG-119 parameters. The plan analysis was conducted by Conformity Index and Homogeneity Index. The point dose measurements were conducted with Exradin A16, Semiflex 0.125cc, and Gafchromic EBT3. The plan results show that CI for C-shape target is in the range of 0.710-0.999 at 10 g/cm2 depth and 0.691-1.613 at 5 g/cm2. In addition, HI for C-shape and circular were in the range of 6.3%-58.7% and 5.4%-87.1% for 10 g/cm2 depth. The measurement results show that the dose measurement at inhomogeneous medium and small volume targets are much lower than the criteria in AAPM TG-119. In conclusion, the criteria in the AAPM TG-119 cannot be fully implemented for inhomogeneous medium and small volume targets.

CS-09RTVP-1 PROMOTES THE MESENCHYMAL TRANSFORMATION OF GLIOMA STEM CELLS VIA THE CXCR4 AND IL-6 PATHWAYS

PubMed Central

Giladi, Nis; Lee, Hae Kyung; Finniss, Susan; Cazacu, Simona; Xiang, Cunli; Poisson, Laila; Mikkelsen, Tom; Ziv-Av, Amotz; Brodie, Chaya

2014-01-01

Glioblastoma (GBM), the most aggressive primary brain tumors, are categorized into the major subgroups: proneural, neural, classical and mesenchymal, the latter being characterized by increased invasion and poor prognosis. We recently identified RTVP-1 as a glioma-associated protein that regulates glioma cell migration and invasion. Using ChiP analyses, we found that the RTVP-1 promoter binds STAT3 and C/EBPbeta, the two master transcription factors that regulate mesenchymal transformation of GBM. Analysis of TCGA tumor specimens demonstrated that the expression of RTVP-1 was higher in the mesenchymal GBM and was inversely correlated with patient survival. We further found that RTVP-1 was expressed in glioma stem cells (GSCs) but not in human neural stem cells (NSCs). Overexpression of RTVP-1 in NSCs induced their mesenchymal transformation, whereas silencing of RTVP-1 in GSCs decreased their mesenchymal signature, increased their neural phenotypes and inhibited the self renewal and stemness of these cells. Silencing of RTVP-1 also decreased tumor volume of GSC-derived xenografts and increased animal survival. Using gene array analysis of RTVP-1 silenced cells we identified IL-6 and CXCR4 as major mediators of RTVP-1 effects on the mesenchymal transformation and self-renewal of GSCs. Using a pull down assay with His-tagged RTVP-1 and FRET analysis, we identified HSP27, N-WASP and hnRNPK as novel interacting proteins of RTVP-1, that mediate its effects on GSC migration and invadopodia formation. In summary, RTVP-1 expression is regulated by STAT3 and CEBPbeta and is promoting the mesenchymal transformation of GSCs. RTVP-1 induces self-renewal and migration of GSCs by the increased expression of IL-6 and CXCR4 and via its interaction with N-WASP, hnRNPK and HSP27. The upregulation of IL-6 by RTVP-1 acts in a positive feedback loop to further increase RTVP-1 expression by activating the STAT3 pathway. Collectively, these results implicate RTVP-1 as a novel prognostic marker and therapeutic target in GBM.

MO-F-CAMPUS-T-02: Optimizing Orientations of Hundreds of Intensity-Modulated Beams to Treat Multiple Brain Targets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ma, L; Dong, P; Larson, D

Purpose: To investigate a new modulated beam orientation optimization (MBOO) approach maximizing treatment planning quality for the state-of-the-art flattening filter free (FFF) beam that has enabled rapid treatments of multiple brain targets. Methods: MBOO selects and optimizes a large number of intensity-modulated beams (400 or more) from all accessible beam angles surrounding a patient’s skull. The optimization algorithm was implemented on a standalone system that interfaced with the 3D Dicom images and structure sets. A standard published data set that consisted of 1 to 12 metastatic brain tumor combinations was selected for MBOO planning. The planning results from various coplanarmore » and non-coplanar configurations via MBOO were then compared with the results obtained from a clinical volume modulated arc therapy (VMAT) delivery system (Truebeam RapidArc, Varian Oncology). Results: When planning a few number of targets (n<4), MBOO produced results equivalent to non-coplanar multi-arc VMAT planning in terms of target volume coverage and normal tissue sparing. For example, the 12-Gy and 4-Gy normal brain volumes for the 3-target plans differed by less than 1 mL ( 3.0 mLvs 3.8 mL; and 35.2 mL vs 36.3 mL, respectively) for MBOO versus VMAT. However, when planning a larger number of targets (n≥4), MBOO significantly reduced the dose to the normal brain as compared to VMAT, though the target volume coverage was equivalent. For example, the 12-Gy and 4-Gy normal brain volumes for the 12-target plans were 10.8 mL vs. 18.0 mL and 217.9 mL vs. 390.0 mL, respectively for the non-coplanar MBOO versus the non-coplanar VMAT treatment plans, yielding a reduction in volume of more than 60% for the case. Conclusion: MBOO is a unique approach for maximizing normal tissue sparing when treating a large number (n≥4) of brain tumors with FFF linear accelerators. Dr Ma and Dr Sahgal are currently on the board of international society of stereotactic radiosurgery. Dr Sahgal has received support for educational presentations from Elekta company.« less

Feature Transformation Detection Method with Best Spectral Band Selection Process for Hyper-spectral Imaging

NASA Astrophysics Data System (ADS)

Chen, Hai-Wen; McGurr, Mike; Brickhouse, Mark

2015-11-01

We present a newly developed feature transformation (FT) detection method for hyper-spectral imagery (HSI) sensors. In essence, the FT method, by transforming the original features (spectral bands) to a different feature domain, may considerably increase the statistical separation between the target and background probability density functions, and thus may significantly improve the target detection and identification performance, as evidenced by the test results in this paper. We show that by differentiating the original spectral, one can completely separate targets from the background using a single spectral band, leading to perfect detection results. In addition, we have proposed an automated best spectral band selection process with a double-threshold scheme that can rank the available spectral bands from the best to the worst for target detection. Finally, we have also proposed an automated cross-spectrum fusion process to further improve the detection performance in lower spectral range (<1000 nm) by selecting the best spectral band pair with multivariate analysis. Promising detection performance has been achieved using a small background material signature library for concept-proving, and has then been further evaluated and verified using a real background HSI scene collected by a HYDICE sensor.

Literacy Is Transformative. The Thirty-Fifth Yearbook A Doubled Peer Reviewed Publication of the Association of Literacy Educators and Researchers

ERIC Educational Resources Information Center

Szabo, Susan, Ed.; Martin, Linda, Ed.; Haas, Leslie, Ed.; Garza-Garcia, Lizabeth, Ed.

2013-01-01

For their 56th annual meeting, the Association of Educators and Researchers (ALER) met in Grand Rapids, Michigan at the Amway Grand Hotel. This year's conference theme was Literacy Is Transformative, which was also used as the title for this year's Yearbook, Volume 35. Included are double-peer reviewed papers, the presidential address,…

Registering coherent change detection products associated with large image sets and long capture intervals

DOEpatents

Perkins, David Nikolaus; Gonzales, Antonio I

2014-04-08

A set of co-registered coherent change detection (CCD) products is produced from a set of temporally separated synthetic aperture radar (SAR) images of a target scene. A plurality of transformations are determined, which transformations are respectively for transforming a plurality of the SAR images to a predetermined image coordinate system. The transformations are used to create, from a set of CCD products produced from the set of SAR images, a corresponding set of co-registered CCD products.

International Center For Actuators And Transducers

DTIC Science & Technology

2003-06-01

electromagnetic noise-free systems. The photostrictive effect has also been used recently for a photophonic device, in which light is transformed into sound...of Actuators Loss and Heat Generation Heat generation Temperature riseSurface Area SHeat dissipation Effective Volume V e Total Volume V Driving...and the use of a responsive positioner was considered to compensate for the detrimental effects . YEAR (A.D.) 2000190018001700 Manufacturing (µm) 10

Viewer-centered and body-centered frames of reference in direct visuomotor transformations.

PubMed

Carrozzo, M; McIntyre, J; Zago, M; Lacquaniti, F

1999-11-01

It has been hypothesized that the end-point position of reaching may be specified in an egocentric frame of reference. In most previous studies, however, reaching was toward a memorized target, rather than an actual target. Thus, the role played by sensorimotor transformation could not be disassociated from the role played by storage in short-term memory. In the present study the direct process of sensorimotor transformation was investigated in reaching toward continuously visible targets that need not be stored in memory. A virtual reality system was used to present visual targets in different three-dimensional (3D) locations in two different tasks, one with visual feedback of the hand and arm position (Seen Hand) and the other without such feedback (Unseen Hand). In the Seen Hand task, the axes of maximum variability and of maximum contraction converge toward the mid-point between the eyes. In the Unseen Hand task only the maximum contraction correlates with the sight-line and the axes of maximum variability are not viewer-centered but rotate anti-clockwise around the body and the effector arm during the move from the right to the left workspace. The bulk of findings from these and previous experiments support the hypothesis of a two-stage process, with a gradual transformation from viewer-centered to body-centered and arm-centered coordinates. Retinal, extra-retinal and arm-related signals appear to be progressively combined in superior and inferior parietal areas, giving rise to egocentric representations of the end-point position of reaching.

Disposable blast shields for use on NIF imaging diagnostics

NASA Astrophysics Data System (ADS)

Smith, Cal A.; Wang, Karen M.; Masters, Nathan

2015-08-01

The NIFs 192 lasers can deliver 2 MJ of energy to Target Chamber Center (TCC) to produce environments not available in any other experimental laboratory. The NIFs ability to deliver such intense energy to a small volume causes harsh consequences to experimental equipment and supporting diagnostics such as holhraums, support packages, target positioners, diagnostic equipment, and laser optics. Of these, the hohlraum and support packages are typically quickly vaporized and transformed into an expanding shell of high-hypersonic gases referred to as debris wind. During an experimental event such as fusion implosion, the target diagnostic components used to measure key observables in the experiment are subjected to extreme pressures and impact shocks due to incident debris wind loading. As diagnostics are positioned closer to TCC, the diagnostic pinhole stacks and other components along the diagnostic structure become more likely to be at or above the yield strength of the materials commonly used. In particular, the pinhole stack components and data recording instruments behind the pinholes are the most costly to replace. Thus, a conceptual configuration for a pinhole shield is proposed, analyzed, and tested with the intent of mitigating damage to the pinhole stack and imaging equipment and allowing immediate re-use of this diagnostic equipment. This pinhole shield would be a replaceable window that can be replaced quickly by inserting and removing it before and after each experimental laser shot, which will allow NIF to benefit from significant material and labor costs.

Mod-5A wind turbine generator program design report. Volume 4: Drawings and specifications, book 1

NASA Astrophysics Data System (ADS)

1984-08-01

The design, development and analysis of the 7.3 MW MOD-5A wind turbine generator is documented. Volume 4 contains the drawings and specifications that were developed in preparation for building the MOD-5A wind turbine generator. This is the first of five books of volume four. It contains structural design criteria, generator step-up transformer specs, specs for design, fabrication and testing of the system, specs for the ground control enclosure, systems specs, slip ring specs, and control system specs.

Mod-5A Wind Turbine Generator Program Design Report. Volume 4: Drawings and Specifications, Book 1

NASA Technical Reports Server (NTRS)

1984-01-01

The design, development and analysis of the 7.3 MW MOD-5A wind turbine generator is documented. Volume 4 contains the drawings and specifications that were developed in preparation for building the MOD-5A wind turbine generator. This is the first of five books of volume four. It contains structural design criteria, generator step-up transformer specs, specs for design, fabrication and testing of the system, specs for the ground control enclosure, systems specs, slip ring specs, and control system specs.

Phase transformations and equation of state of praseodymium metal to 103 GPa

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chesnut, Gary N.; Vohra, Yogesh K.

2000-08-01

Pressure-induced structural phase transformations in a trivalent rare-earth metal praseodymium (Pr) were studied at room temperature in a diamond anvil cell to 103 GPa by energy dispersive x-ray diffraction using a synchrotron source. Our x-ray diffraction studies document the following crystal structure sequence: dhcp{yields}fcc{yields}distorted fcc(hR24 type){yields}monoclinic(C2/m){yields}{alpha}-uranium with increasing pressure. We measure a 16.7% volume collapse at the transition to the {alpha}-uranium phase at 20 GPa. The high-pressure {alpha}-uranium phase in Pr was found to be stable to the highest pressure of 103 GPa, which corresponds to a volume compression V/V{sub 0}=0.407. (c) 2000 The American Physical Society.

Time efficient Gabor fused master slave optical coherence tomography

NASA Astrophysics Data System (ADS)

Cernat, Ramona; Bradu, Adrian; Rivet, Sylvain; Podoleanu, Adrian

2018-02-01

In this paper the benefits in terms of operation time that Master/Slave (MS) implementation of optical coherence tomography can bring in comparison to Gabor fused (GF) employing conventional fast Fourier transform based OCT are presented. The Gabor Fusion/Master Slave Optical Coherence Tomography architecture proposed here does not need any data stitching. Instead, a subset of en-face images is produced for each focus position inside the sample to be imaged, using a reduced number of theoretically inferred Master masks. These en-face images are then assembled into a final volume. When the channelled spectra are digitized into 1024 sampling points, and more than 4 focus positions are required to produce the final volume, the Master Slave implementation of the instrument is faster than the conventional fast Fourier transform based procedure.

Agrobacterium-mediated genetic transformation of Coffea arabica (L.) is greatly enhanced by using established embryogenic callus cultures

PubMed Central

2011-01-01

Background Following genome sequencing of crop plants, one of the main challenges today is determining the function of all the predicted genes. When gene validation approaches are used for woody species, the main obstacle is the low recovery rate of transgenic plants from elite or commercial cultivars. Embryogenic calli have frequently been the target tissue for transformation, but the difficulty in producing or maintaining embryogenic tissues is one of the main problems encountered in genetic transformation of many woody plants, including Coffea arabica. Results We identified the conditions required for successful long-term proliferation of embryogenic cultures in C. arabica and designed a highly efficient and reliable Agrobacterium tumefaciens-mediated transformation method based on these conditions. The transformation protocol with LBA1119 harboring pBin 35S GFP was established by evaluating the effect of different parameters on transformation efficiency by GFP detection. Using embryogenic callus cultures, co-cultivation with LBA1119 OD600 = 0.6 for five days at 20 °C enabled reproducible transformation. The maintenance conditions for the embryogenic callus cultures, particularly a high auxin to cytokinin ratio, the age of the culture (optimum for 7-10 months of proliferation) and the use of a yellow callus phenotype, were the most important factors for achieving highly efficient transformation (> 90%). At the histological level, successful transformation was related to the number of proembryogenic masses present. All the selected plants were proved to be transformed by PCR and Southern blot hybridization. Conclusion Most progress in increasing transformation efficiency in coffee has been achieved by optimizing the production conditions of embryogenic cultures used as target tissues for transformation. This is the first time that a strong positive effect of the age of the culture on transformation efficiency was demonstrated. Our results make Agrobacterium-mediated transformation of embryogenic cultures a viable and useful tool both for coffee breeding and for the functional analysis of agronomically important genes. PMID:21595964

STRUCTURE IN THE 3D GALAXY DISTRIBUTION: III. FOURIER TRANSFORMING THE UNIVERSE: PHASE AND POWER SPECTRA.

PubMed

Scargle, Jeffrey D; Way, M J; Gazis, P R

2017-04-10

We demonstrate the effectiveness of a relatively straightforward analysis of the complex 3D Fourier transform of galaxy coordinates derived from redshift surveys. Numerical demonstrations of this approach are carried out on a volume-limited sample of the Sloan Digital Sky Survey redshift survey. The direct unbinned transform yields a complex 3D data cube quite similar to that from the Fast Fourier Transform (FFT) of finely binned galaxy positions. In both cases deconvolution of the sampling window function yields estimates of the true transform. Simple power spectrum estimates from these transforms are roughly consistent with those using more elaborate methods. The complex Fourier transform characterizes spatial distributional properties beyond the power spectrum in a manner different from (and we argue is more easily interpreted than) the conventional multi-point hierarchy. We identify some threads of modern large scale inference methodology that will presumably yield detections in new wider and deeper surveys.

STRUCTURE IN THE 3D GALAXY DISTRIBUTION: III. FOURIER TRANSFORMING THE UNIVERSE: PHASE AND POWER SPECTRA

PubMed Central

Scargle, Jeffrey D.; Way, M. J.; Gazis, P. R.

2017-01-01

We demonstrate the effectiveness of a relatively straightforward analysis of the complex 3D Fourier transform of galaxy coordinates derived from redshift surveys. Numerical demonstrations of this approach are carried out on a volume-limited sample of the Sloan Digital Sky Survey redshift survey. The direct unbinned transform yields a complex 3D data cube quite similar to that from the Fast Fourier Transform (FFT) of finely binned galaxy positions. In both cases deconvolution of the sampling window function yields estimates of the true transform. Simple power spectrum estimates from these transforms are roughly consistent with those using more elaborate methods. The complex Fourier transform characterizes spatial distributional properties beyond the power spectrum in a manner different from (and we argue is more easily interpreted than) the conventional multi-point hierarchy. We identify some threads of modern large scale inference methodology that will presumably yield detections in new wider and deeper surveys. PMID:29628519

Structure in the 3D Galaxy Distribution. III. Fourier Transforming the Universe: Phase and Power Spectra

DOE Office of Scientific and Technical Information (OSTI.GOV)

Scargle, Jeffrey D.; Way, M. J.; Gazis, P. R., E-mail: Jeffrey.D.Scargle@nasa.gov, E-mail: Michael.J.Way@nasa.gov, E-mail: PGazis@sbcglobal.net

We demonstrate the effectiveness of a relatively straightforward analysis of the complex 3D Fourier transform of galaxy coordinates derived from redshift surveys. Numerical demonstrations of this approach are carried out on a volume-limited sample of the Sloan Digital Sky Survey redshift survey. The direct unbinned transform yields a complex 3D data cube quite similar to that from the Fast Fourier Transform of finely binned galaxy positions. In both cases, deconvolution of the sampling window function yields estimates of the true transform. Simple power spectrum estimates from these transforms are roughly consistent with those using more elaborate methods. The complex Fouriermore » transform characterizes spatial distributional properties beyond the power spectrum in a manner different from (and we argue is more easily interpreted than) the conventional multipoint hierarchy. We identify some threads of modern large-scale inference methodology that will presumably yield detections in new wider and deeper surveys.« less

Structure in the 3D Galaxy Distribution: III. Fourier Transforming the Universe: Phase and Power Spectra

NASA Technical Reports Server (NTRS)

Scargle, Jeffrey D.; Way, M. J.; Gazis, P. R.

2017-01-01

We demonstrate the effectiveness of a relatively straightforward analysis of the complex 3D Fourier transform of galaxy coordinates derived from redshift surveys. Numerical demonstrations of this approach are carried out on a volume-limited sample of the Sloan Digital Sky Survey redshift survey. The direct unbinned transform yields a complex 3D data cube quite similar to that from the Fast Fourier Transform (FFT) of finely binned galaxy positions. In both cases deconvolution of the sampling window function yields estimates of the true transform. Simple power spectrum estimates from these transforms are roughly consistent with those using more elaborate methods. The complex Fourier transform characterizes spatial distributional properties beyond the power spectrum in a manner different from (and we argue is more easily interpreted than) the conventional multi-point hierarchy. We identify some threads of modern large scale inference methodology that will presumably yield detections in new wider and deeper surveys.

SU-E-CAMPUS-I-06: Y90 PET/CT for the Instantaneous Determination of Both Target and Non-Target Absorbed Doses Following Hepatic Radioembolization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pasciak, A; Kao, J

2014-06-15

Purpose The process of converting Yttrium-90 (Y90) PET/CT images into 3D absorbed dose maps will be explained. The simple methods presented will allow the medical physicst to analyze Y90 PET images following radioembolization and determine the absorbed dose to tumor, normal liver parenchyma and other areas of interest, without application of Monte-Carlo radiation transport or dose-point-kernel (DPK) convolution. Methods Absorbed dose can be computed from Y90 PET/CT images based on the premise that radioembolization is a permanent implant with a constant relative activity distribution after infusion. Many Y90 PET/CT publications have used DPK convolution to obtain 3D absorbed dose maps.more » However, this method requires specialized software limiting clinical utility. The Local Deposition method, an alternative to DPK convolution, can be used to obtain absorbed dose and requires no additional computer processing. Pixel values from regions of interest drawn on Y90 PET/CT images can be converted to absorbed dose (Gy) by multiplication with a scalar constant. Results There is evidence that suggests the Local Deposition method may actually be more accurate than DPK convolution and it has been successfully used in a recent Y90 PET/CT publication. We have analytically compared dose-volume-histograms (DVH) for phantom hot-spheres to determine the difference between the DPK and Local Deposition methods, as a function of PET scanner point-spread-function for Y90. We have found that for PET/CT systems with a FWHM greater than 3.0 mm when imaging Y90, the Local Deposition Method provides a more accurate representation of DVH, regardless of target size than DPK convolution. Conclusion Using the Local Deposition Method, post-radioembolization Y90 PET/CT images can be transformed into 3D absorbed dose maps of the liver. An interventional radiologist or a Medical Physicist can perform this transformation in a clinical setting, allowing for rapid prediction of treatment efficacy by comparison to published tumoricidal thresholds.« less

Nrf2 activator ameliorates hemorrhagic transformation in focal cerebral ischemia under warfarin anticoagulation.

PubMed

Imai, Takahiko; Takagi, Toshinori; Kitashoji, Akira; Yamauchi, Keita; Shimazawa, Masamitsu; Hara, Hideaki

2016-05-01

Oxidative stress has been reported to be a main cause of neuronal cell death in ischemia reperfusion injury (IRI). Nuclear factor-erythroid 2-related factor 2 (Nrf2) is an important factor involved in anti-oxidative responses. We previously reported that bardoxolone methyl (BARD), an Nrf2 activator, prevented damage induced by IRI. In this study, we investigated the effect of BARD on hemorrhagic transformation in the context of blood brain barrier (BBB) protection. Mice received pre-treatment with warfarin (4.0 mg/kg, p.o.). IRI was subsequently induced 18 h after the warfarin administration by transient middle cerebral artery occlusion (MCAO) for 6 h. BARD (0.06, 0.2, 0.6 or 2.0 mg/kg) or saline was injected intravenously immediately after reperfusion. The infarct volume, neurological score, intracranial hemorrhage volume, and BBB permeability were evaluated 24 h after MCAO. The survival rate and behavioral functional recovery were evaluated for 7 days following IRI. Furthermore, the effects of BARD on BBB components were investigated by western blotting and immunostaining analysis. BARD suppressed warfarin-mediated increases in the intracranial hemorrhage volume without affecting the infarct volume. BBB permeability was also suppressed by administration of BARD. Western blotting showed that BARD increased expression of BBB components such as endothelial cells, pericytes, and tight junction proteins. Furthermore, immunostaining showed that BARD induced localization of Nrf2 to endothelial cells and pericytes. BARD suppressed the exacerbation hemorrhage caused by warfarin pretreatment and ameliorated BBB disruption by protecting endothelial cells, pericytes, and tight junction protein expressions. These results indicate that Nrf2 activators may be an effective therapy against hemorrhagic transformation caused by anticoagulant drugs. Copyright © 2016 Elsevier Inc. All rights reserved.

Mitochondrial Ion Channels in Cancer Transformation

PubMed Central

Madamba, Stephen M.; Damri, Kevin N.; Dejean, Laurent M.; Peixoto, Pablo M.

2015-01-01

Cancer transformation involves reprograming of mitochondrial function to avert cell death mechanisms, monopolize energy metabolism, accelerate mitotic proliferation, and promote metastasis. Mitochondrial ion channels have emerged as promising therapeutic targets because of their connection to metabolic and apoptotic functions. This mini review discusses how mitochondrial channels may be associated with cancer transformation and expands on the possible involvement of mitochondrial protein import complexes in pathophysiological process. PMID:26090338

Dynamic magnetic resonance imaging assessment of vascular targeting agent effects in rat intracerebral tumor models

PubMed Central

Muldoon, Leslie L.; Gahramanov, Seymur; Li, Xin; Marshall, Deborah J.; Kraemer, Dale F.; Neuwelt, Edward A.

2011-01-01

We used dynamic MRI to evaluate the effects of monoclonal antibodies targeting brain tumor vasculature. Female athymic rats with intracerebral human tumor xenografts were untreated or treated with intetumumab, targeting αV-integrins, or bevacizumab, targeting vascular endothelial growth factor (n = 4–6 per group). Prior to treatment and at 1, 3, and 7 days after treatment, we performed standard MRI to assess tumor volume, dynamic susceptibility-contrast MRI with the blood-pool iron oxide nanoparticle ferumoxytol to evaluate relative cerebral blood volume (rCBV), and dynamic contrast-enhanced MRI to assess tumor vascular permeability. Tumor rCBV increased by 27 ± 13% over 7 days in untreated rats; intetumumab increased tumor rCBV by 65 ± 10%, whereas bevacizumab reduced tumor rCBV by 31 ± 10% at 7 days (P < .001 for group and day). Similarly, intetumumab increased brain tumor vascular permeability compared with controls at 3 and 7 days after treatment, whereas bevacizumab decreased tumor permeability within 24 hours (P = .0004 for group, P = .0081 for day). All tumors grew over the 7-day assessment period, but bevacizumab slowed the increase in tumor volume on MRI. We conclude that the vascular targeting agents intetumumab and bevacizumab had diametrically opposite effects on dynamic MRI of tumor vasculature in rat brain tumor models. Targeting αV-integrins increased tumor vascular permeability and blood volume, whereas bevacizumab decreased both measures. These findings have implications for chemotherapy delivery and antitumor efficacy. PMID:21123368

[Definition of nodal volumes in breast cancer treatment and segmentation guidelines].

PubMed

Kirova, Y M; Castro Pena, P; Dendale, R; Campana, F; Bollet, M A; Fournier-Bidoz, N; Fourquet, A

2009-06-01

To assist in the determination of breast and nodal volumes in the setting of radiotherapy for breast cancer and establish segmentation guidelines. Materials and methods. Contrast metarial enhanced CT examinations were obtained in the treatment position in 25 patients to clearly define the target volumes. The clinical target volume (CTV) including the breast, internal mammary nodes, supraclavicular and subclavicular regions and axxilary region were segmented along with the brachial plexus and interpectoral nodes. The following critical organs were also segmented: heart, lungs, contralateral breast, thyroid, esophagus and humeral head. A correlation between clinical and imaging findings and meeting between radiation oncologists and breast specialists resulted in a better definition of irradiation volumes for breast and nodes with establishement of segmentation guidelines and creation of an anatomical atlas. A practical approach, based on anatomical criteria, is proposed to assist in the segmentation of breast and node volumes in the setting of breast cancer treatment along with a definition of irradiation volumes.

Targeted Mutagenesis in Rice Using TALENs and the CRISPR/Cas9 System.

PubMed

Endo, Masaki; Nishizawa-Yokoi, Ayako; Toki, Seiichi

2016-01-01

Sequence-specific nucleases (SSNs), such as zinc-finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), and the clustered regularly interspersed short palindromic repeats (CRISPR)/CRISPR-associated protein 9 nuclease (Cas9) system, are powerful tools for understanding gene function and for developing novel traits in plants. In plant species for which transformation and regeneration systems using protoplasts are not yet established, direct delivery to nuclei of SSNs either in the form of RNA or protein is difficult. Thus, Agrobacterium-mediated transformation of SSN expression constructs in cultured cells is a practical means of delivering targeted mutagenesis in some plant species including rice. Because targeted mutagenesis occurs stochastically in transgenic cells and SSN-mediated targeted mutagenesis often leads to no selectable phenotype, identification of highly mutated cell lines is a critical step in obtaining regenerated plants with desired mutations.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Besemer, A; Marsh, I; Bednarz, B

Purpose: The calculation of 3D internal dose calculations in targeted radionuclide therapy requires the acquisition and temporal coregistration of a serial PET/CT or SPECT/CT images. This work investigates the dosimetric impact of different temporal coregistration methods commonly used for 3D internal dosimetry. Methods: PET/CT images of four mice were acquired at 1, 24, 48, 72, 96, 144 hrs post-injection of {sup 124}I-CLR1404. The therapeutic {sup 131}I-CLR1404 absorbed dose rate (ADR) was calculated at each time point using a Geant4-based MC dosimetry platform using three temporal image coregistration Methods: (1) no coregistration (NC), whole body sequential CT-CT affine coregistration (WBAC), andmore » individual sequential ROI-ROI affine coregistration (IRAC). For NC, only the ROI mean ADR was integrated to obtain ROI mean doses. For WBAC, the CT at each time point was coregistered to a single reference CT. The CT transformations were applied to the corresponding ADR images and the dose was calculated on a voxel-basis within the whole CT volume. For IRAC, each individual ROI was isolated and sequentially coregistered to a single reference ROI. The ROI transformations were applied to the corresponding ADR images and the dose was calculated on a voxel-basis within the ROI volumes. Results: The percent differences in the ROI mean doses were as large as 109%, 88%, and 32%, comparing the WBAC vs. IRAC, NC vs. IRAC, and NC vs. WBAC methods, respectively. The CoV in the mean dose between the all three methods ranged from 2–36%. The pronounced curvature of the spinal cord was not adequately coregistered using WBAC which resulted in large difference between the WBAC and IRAC. Conclusion: The method used for temporal image coregistration can result in large differences in 3D internal dosimetry calculations. Care must be taken to choose the most appropriate method depending on the imaging conditions, clinical site, and specific application. This work is partially funded by NIH Grant R21 CA198392-01.« less

Maxillary sinus volume in patients with impacted canines.

PubMed

Oz, Aslihan Zeynep; Oz, Abdullah Alper; El, Hakan; Palomo, Juan Martin

2017-01-01

To evaluate the maxillary sinus volumes in unilaterally impacted canine patients and to compare the volumetric changes that occur after the eruption of canines to the dental arch using cone beam computed tomography (CBCT). Pre- (T0) and posttreatment (T1) CBCT records of 30 patients were used to calculate maxillary sinus volumes between the impacted and erupted canine sides. The InVivoDental 5.0 program was used to measure the volume of the maxillary sinuses. The distance from impacted canine cusp tip to the target point on the palatal plane was also measured. Right maxillary sinus volume was statistically significantly smaller compared to that of the left maxillary sinus when the canine was impacted on the right side at T0. According to the T1 measurements there was no significant difference between the mean volumes of the impaction side and the contralateral side. The distance from the canine tip to its target point on the palatal plane were 17.17 mm, and the distance from the tip to the target point was 15.14 mm for the left- and right-side impacted canines, respectively, and there was a significant difference between the mean amount of change of both sides of maxillary sinuses after treatment of impacted canines. Orthodontic treatment of impacted canines created a significant increase in maxillary sinus volume when the impacted canines were closer with respect to the maxillary sinus.

Trabecular meshwork ECM remodeling in glaucoma: could RAS be a target?

PubMed

Agarwal, Puneet; Agarwal, Renu

2018-06-14

Disturbances of extracellular matrix (ECM) homeostasis in trabecular meshwork (TM) cause increased aqueous outflow resistance leading to elevated intraocular pressure (IOP) in glaucomatous eyes. Therefore, restoration of ECM homeostasis is a rational approach to prevent disease progression. Since renin-angiotensin system (RAS) inhibition positively alters ECM homeostasis in cardiovascular pathologies involving pressure and volume overload, it is likely that RAS inhibitors reduce IOP primarily by restoring ECM homeostasis. Areas covered: Current evidence showing the presence of RAS components in ocular tissue and its role in regulating aqueous humor dynamics is briefly summarized. The role of RAS in ECM remodeling is discussed both in terms of its effects on ECM synthesis and its breakdown. The mechanisms of ECM remodeling involving interactions of RAS with transforming growth factor-β, Wnt/β-catenin signaling, bone morphogenic proteins, connective tissue growth factor, and matrix metalloproteinases in ocular tissue are discussed. Expert opinion: Current literature strongly indicates a significant role of RAS in ECM remodeling in TM of hypertensive eyes. Hence, IOP-lowering effect of RAS inhibitors may primarily be attributed to restoration of ECM homeostasis in aqueous outflow pathways rather than its vascular effects. However, the mechanistic targets for RAS inhibitors have much wider distribution and consequences, which remain relatively unexplored in TM.

Optical design of an in vivo laparoscopic lighting system.

PubMed

Liu, Xiaolong; Abdolmalaki, Reza Yazdanpanah; Mancini, Gregory J; Tan, Jindong

2017-12-01

This paper proposes an in vivo laparoscopic lighting system design to address the illumination issues, namely poor lighting uniformity and low optical efficiency, existing in the state-of-the-art in vivo laparoscopic cameras. The transformable design of the laparoscopic lighting system is capable of carrying purposefully designed freeform optical lenses for achieving lighting performance with high illuminance uniformity and high optical efficiency in a desired target region. To design freeform optical lenses for extended light sources such as LEDs with Lambertian light intensity distributions, we present an effective and complete freeform optical design method. The procedures include (1) ray map computation by numerically solving a standard Monge-Ampere equation; (2) initial freeform optical surface construction by using Snell's law and a lens volume restriction; (3) correction of surface normal vectors due to accumulated errors from the initially constructed surfaces; and (4) feedback modification of the solution to deal with degraded illuminance uniformity caused by the extended sizes of the LEDs. We employed an optical design software package to evaluate the performance of our laparoscopic lighting system design. The simulation results show that our design achieves greater than 95% illuminance uniformity and greater than 89% optical efficiency (considering Fresnel losses) for illuminating the target surgical region. (2017) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

Accuracy of MRI-compatible contrast media injectors.

PubMed

Saake, M; Wuest, W; Becker, S; Uder, M; Janka, R

2014-03-01

To analyze the exactness of MRI-compatible contrast media (CM) injectors in an experimental setup and clinical use. Ejected fluid volumes and amounts of CM were quantified for single and double piston injections. The focus was on small volumes, as used in pediatric examination and test-bolus measurements. Samples were collected before and after clinical MRI scans and amounts of CM were measured. For single piston injections the volume differences were minimal (mean difference 0.01  ml). For double piston injections the volume of the first injection was decreased (mean 20.74  ml, target 21.00  ml, p < 0.01). After a position change of the Y-piece of the injection system, the amount of CM differed significantly from the target value (mean 1.23  mmol and 0.83  mmol at 1  ml/s flow rate, target 1.00  mmol, p < 0.01), independently of the wait time. The clinical samples confirmed these findings. The pistons of modern CM injectors work exactly. However, for small CM volumes the injected amount of CM can differ significantly from the target value in both directions. Influence factors are an incomplete elimination of air and exchange processes between the CM and saline chaser in the injection system. • In MRI examinations of children and test-bolus measurements, small amounts of CM are used. • The accuracy of single piston injections is high. • In double piston injections the injected amount of CM can differ significantly from the target value. © Georg Thieme Verlag KG Stuttgart · New York.

Dose gradient curve: A new tool for evaluating dose gradient.

PubMed

Sung, KiHoon; Choi, Young Eun

2018-01-01

Stereotactic radiotherapy, which delivers an ablative high radiation dose to a target volume for maximum local tumor control, requires a rapid dose fall-off outside the target volume to prevent extensive damage to nearby normal tissue. Currently, there is no tool to comprehensively evaluate the dose gradient near the target volume. We propose the dose gradient curve (DGC) as a new tool to evaluate the quality of a treatment plan with respect to the dose fall-off characteristics. The average distance between two isodose surfaces was represented by the dose gradient index (DGI) estimated by a simple equation using the volume and surface area of isodose levels. The surface area was calculated by mesh generation and surface triangulation. The DGC was defined as a plot of the DGI of each dose interval as a function of the dose. Two types of DGCs, differential and cumulative, were generated. The performance of the DGC was evaluated using stereotactic radiosurgery plans for virtual targets. Over the range of dose distributions, the dose gradient of each dose interval was well-characterized by the DGC in an easily understandable graph format. Significant changes in the DGC were observed reflecting the differences in planning situations and various prescription doses. The DGC is a rational method for visualizing the dose gradient as the average distance between two isodose surfaces; the shorter the distance, the steeper the dose gradient. By combining the DGC with the dose-volume histogram (DVH) in a single plot, the DGC can be utilized to evaluate not only the dose gradient but also the target coverage in routine clinical practice.

Patterns of recurrence after surgery alone versus preoperative chemoradiotherapy and surgery in the CROSS trials.

PubMed

Oppedijk, Vera; van der Gaast, Ate; van Lanschot, Jan J B; van Hagen, Pieter; van Os, Rob; van Rij, Caroline M; van der Sangen, Maurice J; Beukema, Jannet C; Rütten, Heidi; Spruit, Patty H; Reinders, Janny G; Richel, Dick J; van Berge Henegouwen, Mark I; Hulshof, Maarten C C M

2014-02-10

To analyze recurrence patterns in patients with cancer of the esophagus or gastroesophageal junction treated with either preoperative chemoradiotherapy (CRT) plus surgery or surgery alone. Recurrence pattern was analyzed in patients from the previously published CROSS I and II trials in relation to radiation target volumes. CRT consisted of five weekly courses of paclitaxel and carboplatin combined with a concurrent radiation dose of 41.4 Gy in 1.8-Gy fractions to the tumor and pathologic lymph nodes with margin. Of the 422 patients included from 2001 to 2008, 418 were available for analysis. Histology was mostly adenocarcinoma (75%). Of the 374 patients who underwent resection, 86% were allocated to surgery and 92% to CRT plus surgery. On January 1, 2011, after a minimum follow-up of 24 months (median, 45 months), the overall recurrence rate in the surgery arm was 58% versus 35% in the CRT plus surgery arm. Preoperative CRT reduced locoregional recurrence (LRR) from 34% to 14% (P < .001) and peritoneal carcinomatosis from 14% to 4% (P < .001). There was a small but significant effect on hematogenous dissemination in favor of the CRT group (35% v 29%; P = .025). LRR occurred in 5% within the target volume, in 2% in the margins, and in 6% outside the radiation target volume. In 1%, the exact site in relation to the target volume was unclear. Only 1% had an isolated infield recurrence after CRT plus surgery. Preoperative CRT in patients with esophageal cancer reduced LRR and peritoneal carcinomatosis. Recurrence within the radiation target volume occurred in only 5%, mostly combined with outfield failures.

Variability in target delineation of cervical carcinoma: A Korean radiation oncology group study (KROG 15-06)

PubMed Central

Joo, Ji Hyeon; Cho, Byung Chul; Jeong, Chi Young; Park, Won; Kim, Hak Jae; Yoon, Won Sup; Yoon, Mee Sun; Kim, Ji-Yoon; Choi, Jin Hwa; Choi, Youngmin; Kim, Joo-Young

2017-01-01

Purpose To determine inter-observer variability in target volume definition of cervical cancer in radical and adjuvant radiotherapy (RT) settings. Methods Eight physicians contoured CTVs of 2 patients underwent definitive and postoperative RT. Each volume was analyzed using the individual/median volume ratio and generalized conformity index (CIgen). And center of mass (COM) of each contour was calculated. Expert agreement was quantified using an expectation maximization algorithm for Simultaneous Truth and Performance Level Estimation (STAPLE). Results For definitive RT, the individual/median volume ratio ranged from 0.51 to 1.41, and CIgen was 0.531. Mean 3-dimensional distances of average to each COM were 7.8 mm. For postoperative RT setting, corresponding values were 0.65–1.38, 0.563, and 5.3 mm. Kappa value of expert agreement was 0.65 and 0.67, respectively. STAPLE estimates of the sensitivity, specificity, and kappa measures of inter-physician agreement were 0.73, 0.98, and 0.65 for the definitive and 0.75, 0.98, and 0.67 for the adjuvant radiotherapy setting. The largest difference was observed in the superior-inferior direction, particularly in the upper vagina and the common iliac area. Conclusion As there was still some variability in target delineation, more detailed guidelines for target volume delineation and continuing education would help to reduce this uncertainty. PMID:28301492

Targeting of the N-terminal coiled coil oligomerization interface of BCR interferes with the transformation potential of BCR-ABL and increases sensitivity to STI571.

PubMed

Beissert, Tim; Puccetti, Elena; Bianchini, Andrea; Güller, Saskia; Boehrer, Simone; Hoelzer, Dieter; Ottmann, Oliver Gerhard; Nervi, Clara; Ruthardt, Martin

2003-10-15

Translocations involving the abl locus on chromosome 9 fuses the tyrosine kinase c-ABL to proteins harboring oligomerization interfaces such as BCR or TEL, enabling these ABL-fusion proteins (X-ABL) to transform cells and to induce leukemia. The ABL kinase activity is blocked by the ABL kinase inhibitor STI571 which abrogates transformation by X-ABL. To investigate the role of oligomerization for the transformation potential of X-ABL and for the sensitivity to STI571, we constructed ABL chimeras with oligomerization interfaces of proteins involved in leukemia-associated translocations such as BCR, TEL, PML, and PLZF. We assessed the capacity of these chimeras to form high molecular weight (HMW) complexes as compared with p185(BCR-ABL). There was a direct relationship between the size of HMW complexes formed by these chimeras and their capacity to induce factor independence in Ba/F3 cells, whereas there was an inverse relationship between the size of the HMW complexes and the sensitivity to STI571. The targeting of the oligomerization interface of p185(BCR-ABL) by a peptide representing the coiled coil region of BCR reduced its potential to transform fibroblasts and increased sensitivity to STI571. Our results indicate that targeting of the oligomerization interfaces of the X-ABL enhances the effects of STI571 in the treatment of leukemia caused by X-ABL.

Transgenic oil palm: production and projection.

PubMed

Parveez, G K; Masri, M M; Zainal, A; Majid, N A; Yunus, A M; Fadilah, H H; Rasid, O; Cheah, S C

2000-12-01

Oil palm is an important economic crop for Malaysia. Genetic engineering could be applied to produce transgenic oil palms with high value-added fatty acids and novel products to ensure the sustainability of the palm oil industry. Establishment of a reliable transformation and regeneration system is essential for genetic engineering. Biolistic was initially chosen as the method for oil palm transformation as it has been the most successful method for monocotyledons to date. Optimization of physical and biological parameters, including testing of promoters and selective agents, was carried out as a prerequisite for stable transformation. This has resulted in the successful transfer of reporter genes into oil palm and the regeneration of transgenic oil palm, thus making it possible to improve the oil palm through genetic engineering. Besides application of the Biolistics method, studies on transformation mediated by Agrobacterium and utilization of the green fluorescent protein gene as a selectable marker gene have been initiated. Upon the development of a reliable transformation system, a number of useful targets are being projected for oil palm improvement. Among these targets are high-oleate and high-stearate oils, and the production of industrial feedstock such as biodegradable plastics. The efforts in oil palm genetic engineering are thus not targeted as commodity palm oil. Due to the long life cycle of the palm and the time taken to regenerate plants in tissue culture, it is envisaged that commercial planting of transgenic palms will not occur any earlier than the year 2020.

Pressure-induced magneto-structural transition in iron via a modified solid-state nudged elastic band method

NASA Astrophysics Data System (ADS)

Zarkevich, Nikolai A.; Johnson, Duane D.

2015-03-01

Materials under pressure may exhibit critical electronic and structural transitions that affect equation of states, as known for superconductors and the magneto-structural transformations of iron with both geophysical and planetary implications. While experiments often use constant-pressure (diamond-anvil cell, DAC) measurements, many theoretical results address a constant-volume transitions, which avoid issues with magnetic collapse but cannot be directly compared to experiment. We establish a modified solid-state nudge elastic band (MSS-NEB) method to handle magnetic systems that may exhibit moment (and volume) collapse during transformation. We apply it to the pressure-induced transformation in iron between the low-pressure body-centered cubic (bcc) and the high-pressure hexagonal close-packed (hcp) phases, find the bcc-hcp equilibrium coexistence pressure and a transitional pathway, and compare to shock and DAC experiments. We use methods developed with support by the U.S. Department of Energy (DE-FG02-03ER46026 and DE-AC02-07CH11358). Ames Laboratory is operated for the DOE by Iowa State University under contract DE-AC02-07CH11358.

In-situ visualization of stress-dependent bulk magnetic domain formation by neutron grating interferometry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Betz, B.; École Polytechnique Fédérale de Lausanne, NXMM Laboratory, IMX, CH-1015 Lausanne; Rauscher, P.

The performance and degree of efficiency of industrial transformers are directly influenced by the magnetic properties of high-permeability steel laminations (HPSLs). Industrial transformer cores are built of stacks of single HPSLs. While the insulating coating on each HPSL reduces eddy-current losses in the transformer core, the coating also induces favorable inter-granular tensile stresses that significantly influence the underlying magnetic domain structure. Here, we show that the neutron dark-field image can be used to analyze the influence of the coating on the volume and supplementary surface magnetic domain structures. To visualize the stress effect of the coating on the bulk domainmore » formation, we used an uncoated HPSL and stepwise increased the applied external tensile stress up to 20 MPa. We imaged the domain configuration of the intermediate stress states and were able to reproduce the original domain structure of the coated state. Furthermore, we were able to visualize how the applied stresses lead to a refinement of the volume domain structure and the suppression and reoccurrence of supplementary domains.« less

Optimal Design of Magnetic ComponentsinPlasma Cutting Power Supply

NASA Astrophysics Data System (ADS)

Jiang, J. F.; Zhu, B. R.; Zhao, W. N.; Yang, X. J.; Tang, H. J.

2017-10-01

Phase-shifted transformer and DC reactor are usually needed in chopper plasma cutting power supply. Because of high power rate, the loss of magnetic components may reach to several kilowatts, which seriously affects the conversion efficiency. Therefore, it is necessary to research and design low loss magnetic components by means of efficient magnetic materials and optimal design methods. The main task in this paper is to compare the core loss of different magnetic material, to analyze the influence of transformer structure, winding arrangement and wire structure on the characteristics of magnetic component. Then another task is to select suitable magnetic material, structure and wire in order to reduce the loss and volume of magnetic components. Based on the above outcome, the optimization design process of transformer and dc reactor are proposed in chopper plasma cutting power supply with a lot of solutions. These solutions are analyzed and compared before the determination of the optimal solution in order to reduce the volume and power loss of the two magnetic components and improve the conversion efficiency of plasma cutting power supply.

Transformation-Induced, Geometrically Necessary, Dislocation-Based Flow Curve Modeling of Dual-Phase Steels: Effect of Grain Size

NASA Astrophysics Data System (ADS)

Ramazani, Ali; Mukherjee, Krishnendu; Prahl, Ulrich; Bleck, Wolfgang

2012-10-01

The flow behavior of dual-phase (DP) steels is modeled on the finite-element method (FEM) framework on the microscale, considering the effect of the microstructure through the representative volume element (RVE) approach. Two-dimensional RVEs were created from microstructures of experimentally obtained DP steels with various ferrite grain sizes. The flow behavior of single phases was modeled through the dislocation-based work-hardening approach. The volume change during austenite-to-martensite transformation was modeled, and the resultant prestrained areas in the ferrite were considered to be the storage place of transformation-induced, geometrically necessary dislocations (GNDs). The flow curves of DP steels with varying ferrite grain sizes, but constant martensite fractions, were obtained from the literature. The flow curves of simulations that take into account the GND are in better agreement with those of experimental flow curves compared with those of predictions without consideration of the GND. The experimental results obeyed the Hall-Petch relationship between yield stress and flow stress and the simulations predicted this as well.

Plants having modified response to ethylene by transformation with an ETR nucleic acid

DOEpatents

Meyerowitz, Elliott M.; Chang, Caren; Bleecker, Anthony B.

2001-01-01

The invention includes transformed plants having at least one cell transformed with a modified ETR nucleic acid. Such plants have a phenotype characterized by a decrease in the response of at least one transformed plant cell to ethylene as compared to a plant not containing the transformed plant cell. Tissue and/or temporal specificity for expression of the modified ETR nucleic acid is controlled by selecting appropriate expression regulation sequences to target the location and/or time of expression of the transformed nucleic acid. The plants are made by transforming at least one plant cell with an appropriate modified ETR nucleic acid, regenerating plants from one or more of the transformed plant cells and selecting at least one plant having the desired phenotype.

Long-term exposure to fine particulate matter, residential proximity to major roads and measures of brain structure.

PubMed

Wilker, Elissa H; Preis, Sarah R; Beiser, Alexa S; Wolf, Philip A; Au, Rhoda; Kloog, Itai; Li, Wenyuan; Schwartz, Joel; Koutrakis, Petros; DeCarli, Charles; Seshadri, Sudha; Mittleman, Murray A

2015-05-01

Long-term exposure to ambient air pollution is associated with cerebrovascular disease and cognitive impairment, but whether it is related to structural changes in the brain is not clear. We examined the associations between residential long-term exposure to ambient air pollution and markers of brain aging using magnetic resonance imaging. Framingham Offspring Study participants who attended the seventh examination were at least 60 years old and free of dementia and stroke were included. We evaluated associations between exposures (fine particulate matter [PM2.5] and residential proximity to major roadways) and measures of total cerebral brain volume, hippocampal volume, white matter hyperintensity volume (log-transformed and extensive white matter hyperintensity volume for age), and covert brain infarcts. Models were adjusted for age, clinical covariates, indicators of socioeconomic position, and temporal trends. A 2-μg/m(3) increase in PM2.5 was associated with -0.32% (95% confidence interval, -0.59 to -0.05) smaller total cerebral brain volume and 1.46 (95% confidence interval, 1.10 to 1.94) higher odds of covert brain infarcts. Living further away from a major roadway was associated with 0.10 (95% confidence interval, 0.01 to 0.19) greater log-transformed white matter hyperintensity volume for an interquartile range difference in distance, but no clear pattern of association was observed for extensive white matter. Exposure to elevated levels of PM2.5 was associated with smaller total cerebral brain volume, a marker of age-associated brain atrophy, and with higher odds of covert brain infarcts. These findings suggest that air pollution is associated with insidious effects on structural brain aging even in dementia- and stroke-free persons. © 2015 American Heart Association, Inc.

Architecture and data processing alternatives for Tse computer. Volume 1: Tse logic design concepts and the development of image processing machine architectures

NASA Technical Reports Server (NTRS)

Rickard, D. A.; Bodenheimer, R. E.

1976-01-01

Digital computer components which perform two dimensional array logic operations (Tse logic) on binary data arrays are described. The properties of Golay transforms which make them useful in image processing are reviewed, and several architectures for Golay transform processors are presented with emphasis on the skeletonizing algorithm. Conventional logic control units developed for the Golay transform processors are described. One is a unique microprogrammable control unit that uses a microprocessor to control the Tse computer. The remaining control units are based on programmable logic arrays. Performance criteria are established and utilized to compare the various Golay transform machines developed. A critique of Tse logic is presented, and recommendations for additional research are included.

Plants having modified response to ethylene

DOEpatents

Meyerowitz, Elliott M.; Chang, Caren; Bleecker, Anthony B.

1997-01-01

The invention includes transformed plants having at least one cell transformed with a modified ETR nucleic acid. Such plants have a phenotype characterized by a decrease in the response of at least one transformed plant cell to ethylene as compared to a plant not containing the transformed plant cell. Tissue and/or temporal specificity for expression of the modified ETR nucleic acid is controlled by selecting appropriate expression regulation sequences to target the location and/or time of expression of the transformed nucleic acid. The plants are made by transforming at least one plant cell with an appropriate modified ETR nucleic acid, regenerating plants from one or more of the transformed plant cells and selecting at least one plant having the desired phenotype.

Plants having modified response to ethylene

DOEpatents

Meyerowitz, E.M.; Chang, C.; Bleecker, A.B.

1998-10-20

The invention includes transformed plants having at least one cell transformed with a modified ETR nucleic acid. Such plants have a phenotype characterized by a decrease in the response of at least one transformed plant cell to ethylene as compared to a plant not containing the transformed plant cell. Tissue and/or temporal specificity for expression of the modified ETR nucleic acid is controlled by selecting appropriate expression regulation sequences to target the location and/or time of expression of the transformed nucleic acid. The plants are made by transforming at least one plant cell with an appropriate modified ETR nucleic acid, regenerating plants from one or more of the transformed plant cells and selecting at least one plant having the desired phenotype. 67 figs.

Plants having modified response to ethylene

DOEpatents

Meyerowitz, Elliot M.; Chang, Caren; Bleecker, Anthony B.

1998-01-01

The invention includes transformed plants having at least one cell transformed with a modified ETR nucleic acid. Such plants have a phenotype characterized by a decrease in the response of at least one transformed plant cell to ethylene as compared to a plant not containing the transformed plant cell. Tissue and/or temporal specificity for expression of the modified ETR nucleic acid is controlled by selecting appropriate expression regulation sequences to target the location and/or time of expression of the transformed nucleic acid. The plants are made by transforming at least one plant cell with an appropriate modified ETR nucleic acid, regenerating plants from one or more of the transformed plant cells and selecting at least one plant having the desired phenotype.

Plants having modified response to ethylene

DOEpatents

Meyerowitz, E.M.; Chang, C.; Bleecker, A.B.

1997-11-18

The invention includes transformed plants having at least one cell transformed with a modified ETR nucleic acid. Such plants have a phenotype characterized by a decrease in the response of at least one transformed plant cell to ethylene as compared to a plant not containing the transformed plant cell. Tissue and/or temporal specificity for expression of the modified ETR nucleic acid is controlled by selecting appropriate expression regulation sequences to target the location and/or time of expression of the transformed nucleic acid. The plants are made by transforming at least one plant cell with an appropriate modified ETR nucleic acid, regenerating plants from one or more of the transformed plant cells and selecting at least one plant having the desired phenotype. 31 figs.

Recognition of A. thaliana centromeres by heterologous CENH3 requires high similarity to the endogenous protein.

PubMed

Moraes, Izabel C R; Lermontova, Inna; Schubert, Ingo

2011-02-01

The centromere is an essential chromosomal component assembling the kinetochore for chromosome attachment to the spindle microtubules and for directing the chromosome segregation during nuclear division. Kinetochore assembly requires deposition of the centromeric histone H3 variant (CENH3) into centromeric nucleosomes. CENH3 has a variable N-terminal and a more conserved C-terminal part, including the loop1 region of the histone fold domain, which is considered to be critical for centromere targeting. To investigate the structural requirements for centromere targeting, constructs for EYFP-tagged CENH3 of A. lyrata, A. arenosa, Capsella bursa-pastoris, Zea mays and Luzula nivea (the latter with holocentric chromosomes) were transformed into A. thaliana. Except for LnCENH3, all recombinant CENH3 proteins targeted A. thaliana centromeres, but the more distantly related the heterologous protein is, the lower is the efficiency of targeting. Alignment of CENH3 sequences revealed that the tested species share only three amino acids at loop1 region: threonine2, arginine12 and alanine15. These three amino acids were substituted by asparagine, proline and valine encoding sequences within a recombinant EYFP-AtCENH3 construct via PCR mutagenesis prior to transformation of A. thaliana. After transformation, immunostaining of root tip nuclei with anti-GFP antibodies yielded only diffuse signals, indicating that the original three amino acids are necessary but not sufficient for targeting A. thaliana centromeres.

3D craniofacial registration using thin-plate spline transform and cylindrical surface projection

PubMed Central

Chen, Yucong; Deng, Qingqiong; Duan, Fuqing

2017-01-01

Craniofacial registration is used to establish the point-to-point correspondence in a unified coordinate system among human craniofacial models. It is the foundation of craniofacial reconstruction and other craniofacial statistical analysis research. In this paper, a non-rigid 3D craniofacial registration method using thin-plate spline transform and cylindrical surface projection is proposed. First, the gradient descent optimization is utilized to improve a cylindrical surface fitting (CSF) for the reference craniofacial model. Second, the thin-plate spline transform (TPST) is applied to deform a target craniofacial model to the reference model. Finally, the cylindrical surface projection (CSP) is used to derive the point correspondence between the reference and deformed target models. To accelerate the procedure, the iterative closest point ICP algorithm is used to obtain a rough correspondence, which can provide a possible intersection area of the CSP. Finally, the inverse TPST is used to map the obtained corresponding points from the deformed target craniofacial model to the original model, and it can be realized directly by the correspondence between the original target model and the deformed target model. Three types of registration, namely, reflexive, involutive and transitive registration, are carried out to verify the effectiveness of the proposed craniofacial registration algorithm. Comparison with the methods in the literature shows that the proposed method is more accurate. PMID:28982117

3D craniofacial registration using thin-plate spline transform and cylindrical surface projection.

PubMed

Chen, Yucong; Zhao, Junli; Deng, Qingqiong; Duan, Fuqing

2017-01-01

Craniofacial registration is used to establish the point-to-point correspondence in a unified coordinate system among human craniofacial models. It is the foundation of craniofacial reconstruction and other craniofacial statistical analysis research. In this paper, a non-rigid 3D craniofacial registration method using thin-plate spline transform and cylindrical surface projection is proposed. First, the gradient descent optimization is utilized to improve a cylindrical surface fitting (CSF) for the reference craniofacial model. Second, the thin-plate spline transform (TPST) is applied to deform a target craniofacial model to the reference model. Finally, the cylindrical surface projection (CSP) is used to derive the point correspondence between the reference and deformed target models. To accelerate the procedure, the iterative closest point ICP algorithm is used to obtain a rough correspondence, which can provide a possible intersection area of the CSP. Finally, the inverse TPST is used to map the obtained corresponding points from the deformed target craniofacial model to the original model, and it can be realized directly by the correspondence between the original target model and the deformed target model. Three types of registration, namely, reflexive, involutive and transitive registration, are carried out to verify the effectiveness of the proposed craniofacial registration algorithm. Comparison with the methods in the literature shows that the proposed method is more accurate.

An estimation of vehicle kilometer traveled and on-road emissions using the traffic volume and travel speed on road links in Incheon City.

PubMed

Jung, Sungwoon; Kim, Jounghwa; Kim, Jeongsoo; Hong, Dahee; Park, Dongjoo

2017-04-01

The objective of this study is to estimate the vehicle kilometer traveled (VKT) and on-road emissions using the traffic volume in urban. We estimated two VKT; one is based on registered vehicles and the other is based on traffic volumes. VKT for registered vehicles was 2.11 times greater than that of the applied traffic volumes because each VKT estimation method is different. Therefore, we had to define the inner VKT is moved VKT inner in urban to compare two values. Also, we focused on freight modes because these are discharged much air pollutant emissions. From analysis results, we found middle and large trucks registered in other regions traveled to target city in order to carry freight, target city has included many industrial and logistics areas. Freight is transferred through the harbors, large logistics centers, or via locations before being moved to the final destination. During this process, most freight is moved by middle and large trucks, and trailers rather than small trucks for freight import and export. Therefore, these trucks from other areas are inflow more than registered vehicles. Most emissions from diesel trucks had been overestimated in comparison to VKT from applied traffic volumes in target city. From these findings, VKT is essential based on traffic volume and travel speed on road links in order to estimate accurately the emissions of diesel trucks in target city. Our findings support the estimation of the effect of on-road emissions on urban air quality in Korea. Copyright © 2016. Published by Elsevier B.V.

[Clinical target volume delineation for radiotherapy of the esophagus].

PubMed

Lazarescu, I; Thureau, S; Nkhali, L; Pradier, O; Dubray, B

2013-10-01

The dense lymphatic network of the esophagus facilitates tumour spreading along the cephalo-caudal axis and to locoregional lymph nodes. A better understanding of microscopic invasion by tumour cells, based on histological analysis of surgical specimens and analysis of recurrence sites, has justified a reduction in radiotherapy target volumes. The delineation of the clinical target volume (CTV) depends on tumour characteristics (site, histology) and on its spread as assessed on endoscopic ultrasonography and ((18)F)-fluorodeoxyglucose positron-emission tomography (FDG-PET). We propose that positive and negative predictive values for FDG-PET should be used to adapt the CTV according to the risk of nodal involvement. Copyright © 2013 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

Conduction-coupled Tesla transformer.

PubMed

Reed, J L

2015-03-01

A proof-of-principle Tesla transformer circuit is introduced. The new transformer exhibits the high voltage-high power output signal of shock-excited transformers. The circuit, with specification of proper circuit element values, is capable of obtaining extreme oscillatory voltages. The primary and secondary portions of the circuit communicate solely by conduction. The destructive arcing between the primary and secondary inductors in electromagnetically coupled transformers is ubiquitous. Flashover is eliminated in the new transformer as the high-voltage inductors do not interpenetrate and so do not possess an annular volume of electric field. The inductors are remote from one another. The high voltage secondary inductor is isolated in space, except for a base feed conductor, and obtains earth by its self-capacitance to the surroundings. Governing equations, for the ideal case of no damping, are developed from first principles. Experimental, theoretical, and circuit simulator data are presented for the new transformer. Commercial high-temperature superconductors are discussed as a means to eliminate the counter-intuitive damping due to small primary inductances in both the electromagnetic-coupled and new conduction-coupled transformers.

Studies on the controllable transformation of ferrihydrite

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu Hui, E-mail: liuhuicn@126.co; Ma, Miaorui; Qin, Mei

2010-09-15

Ferrihydrite was prepared by two different procedures. Ferrihydrite-1 was prepared by dropping NaOH solution into Fe(III) solution. Ferrihydrite-2 was prepared by adding Fe(III) and NaOH solutions into a certain volume of water simultaneously. Our earlier results obtained at {approx}100 {sup o}C have shown that the structure of ferrihydrite-2 favors its solid state transformation mechanism. Further research reveals that the structure of ferrihydrite-2 favors its dissolution re-crystallization mechanism at a temperature of {<=}60 {sup o}C. Based on the transformation mechanism of ferrihydrite at different temperatures, the controllable transformation from ferrihydrite to various iron (hydr)oxides such as lepidocrocite, goethite, hematite and magnetitemore » can be achieved by adjusting the pH, transformation temperature, transformation time, the amount of Fe(II) as well as the preparation procedures of ferrihydrite. The results in the present paper give a nice example that the transformation of a precursor can be controlled with the help of mechanism. - Graphical abstract: The transformations from ferrihydrite to lepidocrocite, goethite, hematite or magnetite can be controlled with the help of mechanism.« less

Encapsulating Metal Clusters and Acid Sites within Small Voids: Synthetic Strategies and Catalytic Consequences

NASA Astrophysics Data System (ADS)

Goel, Sarika

The selective encapsulation of metal clusters within zeolites can be used to prepare clusters that are uniform in diameter and to protect them against sintering and contact with feed impurities, while concurrently allowing active sites to select reactants based on their molecular size, thus conferring enzyme-like specificity to chemical catalysis. The apertures in small and medium-pore zeolites preclude the use of post-synthetic protocols to encapsulate the relevant metal precursors because cationic or anionic precursors with their charge-balancing double layer and gaseous complexes cannot diffuse through their windows or channels. We have developed general strategies to encapsulate metal clusters within small-pore zeolites by using metal precursors stabilized by ammonia or organic amine ligands, which stabilize metal precursors against their premature precipitation at the high temperature and pH conditions required for the hydrothermal synthesis of the target zeolite structures and favor interactions between metal precursors and incipient aluminosilicate nuclei during the self-assembly of microporous frameworks. When synthesis temperatures were higher than 400 K, available ligands were unable to prevent the premature precipitation of the metal precursors. In such cases, encapsulation was achieved instead via interzeolite transformations after successfully encapsulating metal precursors or clusters via post-synthesis exchange or ligand protection into parent zeolites and subsequently converting them into the target structures while retaining the encapsulated clusters or precursors. Such strategies led to the successful selective encapsulation of a wide range of metal clusters (Pt, Pd, Ru, Rh, Ir, Re, and Ag) within small-pore (SOD (sodalite), LTA (Linde type A (zeolite A)), GIS (gismondine), and ANA (analcime)) and medium-pore (MFI (ZSM-5)) zeolites. These protocols provide novel and diverse mechanism-based strategies for the design of catalysts with protected active sites. We have demonstrated the selectivity of the encapsulation processes by combining transmission electron microscopy and chemisorptive titrations with rigorous catalytic assessments of the ability of these materials to catalyze reactions of small molecules, which can access the intracrystalline voids, but not of larger molecules that cannot access the metal clusters within such voids. The selective confinement of clusters also prevented their contact with sulfur compounds (e.g., thiophene and H2S), thus allowing reactions to occur at conditions that otherwise render unconfined clusters unreactive. We have also developed synthetic protocols and guiding principles, inspired by mechanistic considerations, for the synthesis of zeolites via interzeolite transformations without the use of organic structure-directing agents (OSDA). More specifically, we have synthesized high-silica MFI (ZSM-5), CHA (chabazite), STF (SSZ-35) and MTW (ZSM-12) zeolites from FAU (faujasite) or BEA (beta) parent materials. Structures with lower framework densities (FAU or BEA) were successfully transformed into thermodynamically-favored, more stable structures with higher framework densities (MFI, CHA, STF, and MTW); to date, target materials with higher Si/Al ratios (Si/Al >10) have not been synthesized via interzeolite transformations without the aid of the OSDA species used to discover these zeolite structures and deemed essential up until now for their successful synthesis. Overcoming kinetic hurdles in such transformations required either the presence of common composite building units (CBU) between parent and target structures or, in their absence, the introduction of small amount of seeds of the daughter structures. The NaOH/SiO2 ratio, H2O/SiO2 ratio and Al content in reagents are used to enforce synchronization between the swelling and local restructuring within parent zeolite domains with the spalling of fragments or building units from seeds of the target structure. The pseudomorphic nature of these seed-mediated transformations, which conserve the volume occupied by the parent crystals and lead to similar size and crystal shape in products, reflect incipient nucleation of target structures occurring at the outer regions of the parent domains and lead to the formation of mesoporosity as a natural consequence of the space-conserving nature of these structural changes and of the higher density of the daughter frameworks. The synthesis mechanism and the guidelines developed enable us to enforce conditions required for the formation of zeolites that previously required OSDA species for their synthesis, thus expanding to a significant extent the diversity of zeolite frameworks that are accessible via these synthesis protocols and providing potential savings in the time and cost involved in the synthesis of some of these zeolite structures.

Influence of multiple brain metastases’ size and number on the quality of SRS - VMAT dose delivery

NASA Astrophysics Data System (ADS)

Prentou, G.; Koutsouveli, E.; Pantelis, E.; Papagiannis, P.; Georgiou, E.; Karaiskos, P.

2017-11-01

Stereotactic radiosurgery with volumetric modulated arc therapy (SRS-VMAT) has recently been introduced for treatment of multiple brain metastases with a single isocenter. The technique’s high efficiency is nevertheless dependent of metastatic tumors’ characteristics such as size and number. In this work the impact of the metastases’ size and number on the plan quality indices clinically used for plan evaluation and acceptance is investigated. Fifteen targets with a diameter of 1 cm and average volume of 0.7 cm3 and ten targets with a diameter of 2 cm and average volume of 6.5 cm3 were contoured on an anonymized patient CT dataset, in Monaco (Elekta) treatment planning system. VMAT plans for different target volumes (1 and 2 cm in diameter) and various target numbers (1-15) were generated using four non-coplanar arcs and the Agility (Elekta) linear accelerator (5 mm MLC width) using a Monte Carlo dose calculation algorithm and 1mm dose calculation grid resolution. Conformity index (CI), gradient index (GI) and heterogeneity index (HI) were determined for each target. High quality plans were created for both 1 cm and 2 cm in diameter targets for limited (<6) number of targets per plan. For increased number of irradiated targets (>6) both CI and GI, clinically used for plan evaluation and acceptance, were found to deteriorate.

Characterization of a Diamond Ground Y-TZP and Reversion of the Tetragonal to Monoclinic Transformation.

PubMed

Candido, L M; Fais, Lmg; Ferreira, E B; Antonio, S G; Pinelli, Lap

To characterize the surface of an yttria-stabilized zirconia (Y-TZP) ceramic after diamond grinding in terms of its crystalline phase, morphology, mean roughness (Ra), and wettability as well as to determine a thermal treatment to reverse the resulting tetragonal to monoclinic (t-m) transformation. Y-TZP specimens were distributed into different groups according to the actions (or no action) of grinding and irrigation. Grinding was accomplished using a diamond stone at a low speed. The samples were characterized by x-ray diffraction (XRD), scanning electron microscopy, goniometry, and profilometry. In situ high-temperature XRD was used to determine an annealing temperature to reverse the t-m transformation. Ra was submitted to the Kruskal-Wallis test, followed by the Dunn test (α=0.05). The volume fraction of the monoclinic phase and contact angle were submitted to one-way analysis of variance, followed by the Tukey test (α=0.05). Monoclinic zirconia was observed on the surface of samples after dry and wet grinding with a diamond stone. The volume fraction of the monoclinic phase was smaller on the dry ground samples (3.6%±0.3%) than on the wet ground samples (5.6%±0.3%). High-temperature XRD showed reversion of the t-m phase transformation, which started at 700°C and completed at 800°C in a conventional oven. Grinding with a diamond stone partially transformed the crystalline phase on the surface of a Y-TZP ceramic from tetragonal to monoclinic zirconia while simultaneously increasing the surface roughness and wettability. The t-m transformation could be reversed by heat treatment at 800°C or 900°C for 60 minutes or 1000°C for 30 minutes.

Investigation of Presage 3D Dosimetry as a Method of Clinically Intuitive Quality Assurance and Comparison to a Semi-3D Delta4 System

NASA Astrophysics Data System (ADS)

Crockett, Ethan Van

The need for clinically intuitive metrics for patient-specific quality assurance in radiation therapy has been well-documented (Zhen, Nelms et al. 2011). A novel transform method has shown to be effective at converting full-density 3D dose measurements made in a phantom to dose values in the patient geometry, enabling comparisons using clinically intuitive metrics such as dose-volume histograms (Oldham et al. 2011). This work investigates the transform method and compares its calculated dose-volume histograms (DVHs) to DVH values calculated by a Delta4 QA device (Scandidos), marking the first comparison of a true 3D system to a semi-3D device using clinical metrics. Measurements were made using Presage 3D dosimeters, which were readout by an in-house optical-CT scanner. Three patient cases were chosen for the study: one head-and-neck VMAT treatment and two spine IMRT treatments. The transform method showed good agreement with the planned dose values for all three cases. Furthermore, the transformed DVHs adhered to the planned dose with more accuracy than the Delta4 DVHs. The similarity between the Delta4 DVHs and the transformed DVHs, however, was greater for one of the spine cases than it was for the head-and-neck case, implying that the accuracy of the Delta4 Anatomy software may vary from one treatment site to another. Overall, the transform method, which incorporates data from full-density 3D dose measurements, provides clinically intuitive results that are more accurate and consistent than the corresponding results from a semi-3D Delta 4 system.

Automatic lithofacies segmentation from well-logs data. A comparative study between the Self-Organizing Map (SOM) and Walsh transform

NASA Astrophysics Data System (ADS)

Aliouane, Leila; Ouadfeul, Sid-Ali; Rabhi, Abdessalem; Rouina, Fouzi; Benaissa, Zahia; Boudella, Amar

2013-04-01

The main goal of this work is to realize a comparison between two lithofacies segmentation techniques of reservoir interval. The first one is based on the Kohonen's Self-Organizing Map neural network machine. The second technique is based on the Walsh transform decomposition. Application to real well-logs data of two boreholes located in the Algerian Sahara shows that the Self-organizing map is able to provide more lithological details that the obtained lithofacies model given by the Walsh decomposition. Keywords: Comparison, Lithofacies, SOM, Walsh References: 1)Aliouane, L., Ouadfeul, S., Boudella, A., 2011, Fractal analysis based on the continuous wavelet transform and lithofacies classification from well-logs data using the self-organizing map neural network, Arabian Journal of geosciences, doi: 10.1007/s12517-011-0459-4 2) Aliouane, L., Ouadfeul, S., Djarfour, N., Boudella, A., 2012, Petrophysical Parameters Estimation from Well-Logs Data Using Multilayer Perceptron and Radial Basis Function Neural Networks, Lecture Notes in Computer Science Volume 7667, 2012, pp 730-736, doi : 10.1007/978-3-642-34500-5_86 3)Ouadfeul, S. and Aliouane., L., 2011, Multifractal analysis revisited by the continuous wavelet transform applied in lithofacies segmentation from well-logs data, International journal of applied physics and mathematics, Vol01 N01. 4) Ouadfeul, S., Aliouane, L., 2012, Lithofacies Classification Using the Multilayer Perceptron and the Self-organizing Neural Networks, Lecture Notes in Computer Science Volume 7667, 2012, pp 737-744, doi : 10.1007/978-3-642-34500-5_87 5) Weisstein, Eric W. "Fast Walsh Transform." From MathWorld--A Wolfram Web Resource. http://mathworld.wolfram.com/FastWalshTransform.html

Stable plastid transformation in Scoparia dulcis L.

PubMed

Muralikrishna, Narra; Srinivas, Kota; Kumar, Kalva Bharath; Sadanandam, Abbagani

2016-10-01

In the present investigation we report stable plastid transformation in Scoparia dulcis L., a versatile medicinal herb via particle gun method. The vector KNTc, harbouring aadA as a selectable marker and egfp as a reporter gene which were under the control of synthetic promoter pNG1014a, targets inverted repeats, trnR / t rnN of the plastid genome. By use of this heterologous vector, recovery of transplastomic lines with suitable selection protocol have been successfully established with overall efficiency of two transgenic lines for 25 bombarded leaf explants. PCR and Southern blot analysis demonstrated stable integration of foreign gene into the target sequences. The results represent a significant advancement of the plastid transformation technology in medicinal plants, which relevantly implements a change over in enhancing and regulating of certain metabolic pathways.

Phospholipase C-mediated hydrolysis of phosphatidylcholine is a target of transforming growth factor beta 1 inhibitory signals.

PubMed Central

Diaz-Meco, M T; Dominguez, I; Sanz, L; Municio, M M; Berra, E; Cornet, M E; Garcia de Herreros, A; Johansen, T; Moscat, J

1992-01-01

Cell growth and tumor transformation can be restrained in certain cell systems by the action of transforming growth factor beta (TGF-beta). It has been established that the mechanism whereby TGF-beta 1 inhibits cell growth does not interfere with the triggering of early mitogenic signal transduction mechanisms. Phospholipase C-catalyzed hydrolysis of phosphatidylcholine (PC) is a relatively late step in the cascade activated by growth factors. Therefore, conceivably activation of phospholipase C-catalyzed hydrolysis of PC could be the target of TGF-beta 1 action. In the study reported here, we demonstrate that TGF-beta 1 inhibits the coupling of ras p21 to the activation of PC hydrolysis, which appears to be critical for the antiproliferative effects of TGF-beta 1. Images PMID:1309592

Improving the efficiency of molecular replacement by utilizing a new iterative transform phasing algorithm

DOE Office of Scientific and Technical Information (OSTI.GOV)

He, Hongxing; Fang, Hengrui; Miller, Mitchell D.

2016-07-15

An iterative transform algorithm is proposed to improve the conventional molecular-replacement method for solving the phase problem in X-ray crystallography. Several examples of successful trial calculations carried out with real diffraction data are presented. An iterative transform method proposed previously for direct phasing of high-solvent-content protein crystals is employed for enhancing the molecular-replacement (MR) algorithm in protein crystallography. Target structures that are resistant to conventional MR due to insufficient similarity between the template and target structures might be tractable with this modified phasing method. Trial calculations involving three different structures are described to test and illustrate the methodology. The relationshipmore » of the approach to PHENIX Phaser-MR and MR-Rosetta is discussed.« less

Edaravone, a free radical scavenger, attenuates cerebral infarction and hemorrhagic infarction in rats with hyperglycemia.

PubMed

Okamura, Koichi; Tsubokawa, Tamiji; Johshita, Hiroo; Miyazaki, Hiroshi; Shiokawa, Yoshiaki

2014-01-01

Thrombolysis due to acute ischemic stroke is associated with the risk of hemorrhagic infarction, especially after reperfusion. Recent experimental studies suggest that the main mechanism contributing to hemorrhagic infarction is oxidative stress caused by disruption of the blood-brain barrier. Edaravone, a free radical scavenger, decreases oxidative stress, thereby preventing hemorrhagic infarction during ischemia and reperfusion. In this study, we investigated the effects of edaravone on hemorrhagic infarction in a rat model of hemorrhagic transformation. We used a previously established hemorrhagic transformation model of rats with hyperglycemia. Hyperglycemia was induced by intraperitoneal injection of glucose to all rats (n  =  20). The rats with hyperglycemia showed a high incidence of hemorrhagic infarction. Middle cerebral artery occlusion (MCAO) for 1.5 hours followed by reperfusion for 24 hours was performed in edaravone-treated rats (n  =  10) and control rats (n  =  10). Upon completion of reperfusion, both groups were evaluated for infarct size and hemorrhage volume and the results obtained were compared. Edaravone significantly decreased infarct volume, with the average infarct volume in the edaravone-treated rats (227.6 mm(3)) being significantly lower than that in the control rats (264.0 mm(3)). Edaravone treatment also decreased the postischemic hemorrhage volumes (53.4 mm(3) in edaravone-treated rats vs 176.4 mm(3) in controls). In addition, the ratio of hemorrhage volume to infarct volume was lower in the edaravone-treated rats (23.5%) than in the untreated rats (63.2%). Edaravone attenuates cerebral infarction and hemorrhagic infarction in rats with hyperglycemia.

Real-Time Fourier Transformed Holographic Associative Memory With Photorefractive Material

NASA Astrophysics Data System (ADS)

Changsuk, Oh; Hankyu, Park

1989-02-01

We describe a volume holographic associative memory using photorefractive material and conventional planar mirror. Multiple hologram is generated with two angular multiplexed writing beams and Fourier transformed object beam in BaTiO3 crystal at 0.6328 μm. Complete image can be recalled successfully by partial input of original stored image. It is proved that our system is useful for optical implementation of real-time associative memory and location addressable memory.

Information as Power: An Anthology of Selected United States Army War College Student Papers. Volume 2

DTIC Science & Technology

2007-01-01

Russell H. Smith examines the effectiveness of American public diplomacy and the implications of its success or failure on the 2006 National Security...large measure, the success of U.S. military transformation rests on the belief that a transformed military can gain and maintain information...Kuwaiti sovereignty relied on integrating four of the five core capabilities of today’s IO; OPSEC, MILDEC, PSYOP, and EW. Coalition success

Annual Review of Research under the Joint Services Electronics Program. Volume 1.

DTIC Science & Technology

1982-12-01

time varying nonlinear system be transformable to a controllable time -invariant linear system have been presented. * If a...Conference Papers and Abstracts 1. Hunt, L.R., and R. Su, " Control of Nonlinear Time -Varying Systems ," 20th IEEE Conf. on Decision and Control , pp. 558...being C= vector fields on I,. We give necessary and sufficient conditions for this system to be transformable to a time -invariant controllable

Defense Science Board Summer Study on Transformation: A Progress Assessment. Volume 1

DTIC Science & Technology

2006-02-01

Force Chairmen. Dr. Jerry McGinn, OUSD(P), will serve as the Executive Secretary, and Lt Col Dave Robertson will serve as the Defense Science Board...Sweetzer United States Army Operational Assessment 2005 Col Gail Wojtowicz United States Air Force USAF Brief on Transformation Col Peter Zielinski ...JOC) COL Peter Zielinski CENTCOM Central Command C-10 DSB 2005 SUMMER STUDY ON APPENDICES MULTI-AGENCY INTEGRATION MG Herbert Altshuler Commander

Defense Science Board 2005 Summer Study on Transformation: A Progress Assessment. Volume 2. Supporting Reports

DTIC Science & Technology

2006-04-01

Banking Mr. Robert Luby, IBM Dr. Robert Lucky, Telcordia Technologies Mr. William Lynn, Raytheon Mr. Dave Oliver, EADS North America GOVERNMENT...MAY 2005 Central Command (CENTCOM) COL Peter Zielinski CENTCOM Office of Force Transformation (OFT) Review of COCOM Experimentation COL Richard...for Defense Analyses Mr. Patrick McCarthy, U.S. Joint Forces Command Mr. Stephen Moore, U.S. Joint Forces Command MAY 10, 2005 COL Peter Zielinski

From Main Street to Wall Street: The Transformation of For-Profit Education. ASHE Higher Education Report, Volume 31, Number 5

ERIC Educational Resources Information Center

Kinser, Kevin, Ed.

2006-01-01

This volume has four main goals. The first is to establish a historical perspective on the development of the for-profit sector in the United States. In most contemporary writing, the phenomenon is treated with only cursory attention to the antecedents of the institutions seen today. Although much is new about the current era, much is familiar,…

Apparatus Tests Peeling Of Bonded Rubbery Material

NASA Technical Reports Server (NTRS)

Crook, Russell A.; Graham, Robert

1996-01-01

Instrumented hydraulic constrained blister-peel apparatus obtains data on degree of bonding between specimen of rubbery material and rigid plate. Growth of blister tracked by video camera, digital clock, pressure transducer, and piston-displacement sensor. Cylinder pressure controlled by hydraulic actuator system. Linear variable-differential transformer (LVDT) and float provide second, independent measure of change in blister volume used as more precise volume feedback in low-growth-rate test.

Down-regulation of Rab5 decreases characteristics associated with maintenance of cell transformation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Silva, Patricio; Soto, Nicolás; Díaz, Jorge

2015-08-21

The early endosomal protein Rab5 is highly expressed in tumor samples, although a causal relationship between Rab5 expression and cell transformation has not been established. Here, we report the functional effects of targeting endogenous Rab5 with specific shRNA sequences in different tumor cell lines. Rab5 down-regulation in B16-F10 cells decreased tumor formation by subcutaneous injection into C57/BL6 mice. Accordingly, Rab5 targeting in B16-F10 and A549, but not MDA-MB-231 cells was followed by decreased cell proliferation, increased apoptosis and decreased anchorage-independent growth. These findings suggest that Rab5 expression is required to maintain characteristics associated with cell transformation. - Highlights: • Rab5more » is important to the maintenance of cell transformation characteristics. • Down-regulation of Rab5 decreases cell proliferation and increases apoptosis in different cancer cells. • Rab5 is required for anchorage-independent growth and tumorigenicity in-vivo.« less

Crustal evolution derived from the Izu-Bonin-Mariana arc velocity images

NASA Astrophysics Data System (ADS)

Takahashi, N.; Kodaira, S.; Tatsumi, Y.; Miura, S.; Sato, T.; Yamashita, M.; No, T.; Takahashi, T.; Noguchi, N.; Takizawa, K.; Kaiho, Y.; Kaneda, Y.

2010-12-01

The Izu-Bonin-Mariana arc is known as one of typical oceanic island arcs, which has developed by subduction between oceanic crusts producing continental materials. Japan Agency for Marine-Earth Science and Technology has carried out seismic surveys using a multi-channel reflection survey system (MCS) and ocean bottom seismographs (OBSs) in the Izu-Bonin-Mariana (IBM) arc since 2002, and reported these crustal images. As the results, we identified the structural characteristics of whole Izu-Bonin-Mariana arc. Rough structural characteristics are, 1) middle crust with Vp of 6 km/s, 2) upper part of the lower crust with Vp of 6.5-6.8 km/s, 3) lower part of the lower crust with Vp of 6.8-7.5 km/s, and 4) lower mantle velocity beneath the arc crusts. In addition, structural variation along the volcanic front, for example, thickness variation of andesitic layers was imaged and the distributions is consistent with those of rhyolite volcanoes, that is, it suggested that the cause the structural variation is various degree of crustal growth (Kodaira et al., 2007). Moreover, crustal thinning with high velocity lower crust across arc was also imaged, and it is interpreted that such crust has been influenced backarc opening (Takahashi et al., 2009). According to Tatsumi et al. (2008), andesitic middle crust is produced by differentiation of basaltic lower crust and a part of the restites are transformed to the upper mantle. This means that region showing much crustal differentiation has large volume of transformation of dense crustal materials to the mantle. We calculated volume profiles of the lower crust along all seismic lines based on the petrologic model, and compared them with observed real volumes obtained by seismic images. If the real volume of the lower crust is large, it means that the underplating of dense materials to the crustal bottom is dominant rather than transformation of dense materials to the upper mantle. According to obtained profiles to judge if the region is the transformation dominant or underplating, the transformation dominant regions are located along the volcanic front, the remnant arc for the incipient rifting like the Sumisu Rift just behind the volcanic front, rear arc regions, and fore-arc basins. Beneath the fore-arc basins, multiple rows showing transformation dominant distribute, and it extends from north to south around the Ogasawara Trough. On the other hand, the underplating dominant regions distribute between the volcanic front and the rear arc region, beneath the incipient rift, and between the multiple rows beneath the fore-arc basins. These locations showing underplating dominant are consistent with those with high velocity lower crust.

High-Resolution Wind Measurements for Offshore Wind Energy Development

NASA Technical Reports Server (NTRS)

Nghiem, Son V.; Neumann, Gregory

2011-01-01

A mathematical transform, called the Rosette Transform, together with a new method, called the Dense Sampling Method, have been developed. The Rosette Transform is invented to apply to both the mean part and the fluctuating part of a targeted radar signature using the Dense Sampling Method to construct the data in a high-resolution grid at 1-km posting for wind measurements over water surfaces such as oceans or lakes.

Multiple Frequency Contrast Source Inversion Method for Vertical Electromagnetic Profiling: 2D Simulation Results and Analyses

NASA Astrophysics Data System (ADS)

Li, Jinghe; Song, Linping; Liu, Qing Huo

2016-02-01

A simultaneous multiple frequency contrast source inversion (CSI) method is applied to reconstructing hydrocarbon reservoir targets in a complex multilayered medium in two dimensions. It simulates the effects of a salt dome sedimentary formation in the context of reservoir monitoring. In this method, the stabilized biconjugate-gradient fast Fourier transform (BCGS-FFT) algorithm is applied as a fast solver for the 2D volume integral equation for the forward computation. The inversion technique with CSI combines the efficient FFT algorithm to speed up the matrix-vector multiplication and the stable convergence of the simultaneous multiple frequency CSI in the iteration process. As a result, this method is capable of making quantitative conductivity image reconstruction effectively for large-scale electromagnetic oil exploration problems, including the vertical electromagnetic profiling (VEP) survey investigated here. A number of numerical examples have been demonstrated to validate the effectiveness and capacity of the simultaneous multiple frequency CSI method for a limited array view in VEP.

3D ocular ultrasound using gaze tracking on the contralateral eye: a feasibility study.

PubMed

Afsham, Narges; Najafi, Mohammad; Abolmaesumi, Purang; Rohling, Robert

2011-01-01

A gaze-deviated examination of the eye with a 2D ultrasound transducer is a common and informative ophthalmic test; however, the complex task of the pose estimation of the ultrasound images relative to the eye affects 3D interpretation. To tackle this challenge, a novel system for 3D image reconstruction based on gaze tracking of the contralateral eye has been proposed. The gaze fixates on several target points and, for each fixation, the pose of the examined eye is inferred from the gaze tracking. A single camera system has been developed for pose estimation combined with subject-specific parameter identification. The ultrasound images are then transformed to the coordinate system of the examined eye to create a 3D volume. Accuracy of the proposed gaze tracking system and the pose estimation of the eye have been validated in a set of experiments. Overall system error, including pose estimation and calibration, are 3.12 mm and 4.68 degrees.

Pictorial communication in virtual and real environments

NASA Technical Reports Server (NTRS)

Ellis, Stephen R. (Editor)

1991-01-01

Papers about the communication between human users and machines in real and synthetic environments are presented. Individual topics addressed include: pictorial communication, distortions in memory for visual displays, cartography and map displays, efficiency of graphical perception, volumetric visualization of 3D data, spatial displays to increase pilot situational awareness, teleoperation of land vehicles, computer graphics system for visualizing spacecraft in orbit, visual display aid for orbital maneuvering, multiaxis control in telemanipulation and vehicle guidance, visual enhancements in pick-and-place tasks, target axis effects under transformed visual-motor mappings, adapting to variable prismatic displacement. Also discussed are: spatial vision within egocentric and exocentric frames of reference, sensory conflict in motion sickness, interactions of form and orientation, perception of geometrical structure from congruence, prediction of three-dimensionality across continuous surfaces, effects of viewpoint in the virtual space of pictures, visual slant underestimation, spatial constraints of stereopsis in video displays, stereoscopic stance perception, paradoxical monocular stereopsis and perspective vergence. (No individual items are abstracted in this volume)

Separation and determination of estrogen in the water environment by high performance liquid chromatography-fourier transform infrared spectroscopy

PubMed Central

Zheng, Bei; Li, Wentao; Li, Hongyan; Liu, Lin; Lei, Pei; Ge, Xiaopeng; Yu, Zhiyong; Zhou, Yiqi

2016-01-01

The components for connecting high-performance liquid chromatography (HPLC) with Fourier-transform infrared spectroscopy (FTIR) were investigated to determine estrogen in the water environment, including heating for atomization, solvent removal, sample deposition, drive control, spectrum collection, chip swap, cleaning and drying. Results showed that when the atomization temperature was increased to 388 K, the interference of mobile phase components (methanol, H2O, acetonitrile, and NaH2PO4) were completely removed in the IR measurement of estrogen, with 0.999 of similarity between IR spectra obtained after separation and corresponding to the standard IR spectra. In experiments with varying HPLC injection volumes, high similarity for IR spectra was obtained at 20 ul injection volume at 0.01 mg/L BPA while a useful IR spectrum for 10 ng/L BPA was obtained at 80 ul injection volume. In addition, estrogen concentrations in the natural water samples were calculated semi-quantitatively from the peak intensities of IR spectrum in the mid-infrared region. PMID:27577974

Separation and determination of estrogen in the water environment by high performance liquid chromatography-fourier transform infrared spectroscopy

NASA Astrophysics Data System (ADS)

Zheng, Bei; Li, Wentao; Li, Hongyan; Liu, Lin; Lei, Pei; Ge, Xiaopeng; Yu, Zhiyong; Zhou, Yiqi

2016-08-01

The components for connecting high-performance liquid chromatography (HPLC) with Fourier-transform infrared spectroscopy (FTIR) were investigated to determine estrogen in the water environment, including heating for atomization, solvent removal, sample deposition, drive control, spectrum collection, chip swap, cleaning and drying. Results showed that when the atomization temperature was increased to 388 K, the interference of mobile phase components (methanol, H2O, acetonitrile, and NaH2PO4) were completely removed in the IR measurement of estrogen, with 0.999 of similarity between IR spectra obtained after separation and corresponding to the standard IR spectra. In experiments with varying HPLC injection volumes, high similarity for IR spectra was obtained at 20 ul injection volume at 0.01 mg/L BPA while a useful IR spectrum for 10 ng/L BPA was obtained at 80 ul injection volume. In addition, estrogen concentrations in the natural water samples were calculated semi-quantitatively from the peak intensities of IR spectrum in the mid-infrared region.

Oil Formation Volume Factor Determination Through a Fused Intelligence

NASA Astrophysics Data System (ADS)

Gholami, Amin

2016-12-01

Volume change of oil between reservoir condition and standard surface condition is called oil formation volume factor (FVF), which is very time, cost and labor intensive to determine. This study proposes an accurate, rapid and cost-effective approach for determining FVF from reservoir temperature, dissolved gas oil ratio, and specific gravity of both oil and dissolved gas. Firstly, structural risk minimization (SRM) principle of support vector regression (SVR) was employed to construct a robust model for estimating FVF from the aforementioned inputs. Subsequently, an alternating conditional expectation (ACE) was used for approximating optimal transformations of input/output data to a higher correlated data and consequently developing a sophisticated model between transformed data. Eventually, a committee machine with SVR and ACE was constructed through the use of hybrid genetic algorithm-pattern search (GA-PS). Committee machine integrates ACE and SVR models in an optimal linear combination such that makes benefit of both methods. A group of 342 data points was used for model development and a group of 219 data points was used for blind testing the constructed model. Results indicated that the committee machine performed better than individual models.

Isomap transform for segmenting human body shapes.

PubMed

Cerveri, P; Sarro, K J; Marchente, M; Barros, R M L

2011-09-01

Segmentation of the 3D human body is a very challenging problem in applications exploiting volume capture data. Direct clustering in the Euclidean space is usually complex or even unsolvable. This paper presents an original method based on the Isomap (isometric feature mapping) transform of the volume data-set. The 3D articulated posture is mapped by Isomap in the pose of Da Vinci's Vitruvian man. The limbs are unrolled from each other and separated from the trunk and pelvis, and the topology of the human body shape is recovered. In such a configuration, Hoshen-Kopelman clustering applied to concentric spherical shells is used to automatically group points into the labelled principal curves. Shepard interpolation is utilised to back-map points of the principal curves into the original volume space. The experimental results performed on many different postures have proved the validity of the proposed method. Reliability of less than 2 cm and 3° in the location of the joint centres and direction axes of rotations has been obtained, respectively, which qualifies this procedure as a potential tool for markerless motion analysis.

Targeted Injection of a Biocomposite Material Alters Macrophage and Fibroblast Phenotype and Function following Myocardial Infarction: Relation to Left Ventricular Remodeling

PubMed Central

McGarvey, Jeremy R.; Pettaway, Sara; Shuman, James A.; Novack, Craig P.; Zellars, Kia N.; Freels, Parker D.; Echols, Randall L.; Burdick, Jason A.; Gorman, Joseph H.; Gorman, Robert C.

2014-01-01

A treatment target for progressive left ventricular (LV) remodeling prevention following myocardial infarction (MI) is to affect structural changes directly within the MI region. One approach is through targeted injection of biocomposite materials, such as calcium hydroxyapatite microspheres (CHAM), into the MI region. In this study, the effects of CHAM injections upon key cell types responsible for the MI remodeling process, the macrophage and fibroblast, were examined. MI was induced in adult pigs before randomization to CHAM injections (20 targeted 0.1-ml injections within MI region) or saline. At 7 or 21 days post-MI (n = 6/time point per group), cardiac magnetic resonance imaging was performed, followed by macrophage and fibroblast isolation. Isolated macrophage profiles for monocyte chemotactic macrophage inflammatory protein-1 as measured by real-time polymerase chain reaction increased at 7 days post-MI in the CHAM group compared with MI only (16.3 ± 6.6 versus 1.7 ± 0.6 cycle times values, P < 0.05), and were similar by 21 days post-MI. Temporal changes in fibroblast function and smooth muscle actin (SMA) expression relative to referent control (n = 5) occurred with MI. CHAM induced increases in fibroblast proliferation, migration, and SMA expression—indicative of fibroblast transformation. By 21 days, CHAM reduced LV dilation (diastolic volume: 75 ± 2 versus 97 ± 4 ml) and increased function (ejection fraction: 48 ± 2% versus 38 ± 2%) compared with MI only (both P < 0.05). This study identified that effects on macrophage and fibroblast differentiation occurred with injection of biocomposite material within the MI, which translated into reduced adverse LV remodeling. These unique findings demonstrate that biomaterial injections impart biologic effects upon the MI remodeling process over any biophysical effects. PMID:25022514

Assessment of RNAi-induced silencing in banana (Musa spp.).

PubMed

Dang, Tuong Vi T; Windelinckx, Saskia; Henry, Isabelle M; De Coninck, Barbara; Cammue, Bruno P A; Swennen, Rony; Remy, Serge

2014-09-18

In plants, RNA- based gene silencing mediated by small RNAs functions at the transcriptional or post-transcriptional level to negatively regulate target genes, repetitive sequences, viral RNAs and/or transposon elements. Post-transcriptional gene silencing (PTGS) or the RNA interference (RNAi) approach has been achieved in a wide range of plant species for inhibiting the expression of target genes by generating double-stranded RNA (dsRNA). However, to our knowledge, successful RNAi-application to knock-down endogenous genes has not been reported in the important staple food crop banana. Using embryogenic cell suspension (ECS) transformed with ß-glucuronidase (GUS) as a model system, we assessed silencing of gusAINT using three intron-spliced hairpin RNA (ihpRNA) constructs containing gusAINT sequences of 299-nt, 26-nt and 19-nt, respectively. Their silencing potential was analysed in 2 different experimental set-ups. In the first, Agrobacterium-mediated co-transformation of banana ECS with a gusAINT containing vector and an ihpRNA construct resulted in a significantly reduced GUS enzyme activity 6-8 days after co-cultivation with either the 299-nt and 19-nt ihpRNA vectors. In the second approach, these ihpRNA constructs were transferred to stable GUS-expressing ECS and their silencing potential was evaluated in the regenerated in vitro plants. In comparison to control plants, transgenic plants transformed with the 299-nt gusAINT targeting sequence showed a 4.5 fold down-regulated gusA mRNA expression level, while GUS enzyme activity was reduced by 9 fold. Histochemical staining of plant tissues confirmed these findings. Northern blotting used to detect the expression of siRNA in the 299-nt ihpRNA vector transgenic in vitro plants revealed a negative relationship between siRNA expression and GUS enzyme activity. In contrast, no reduction in GUS activity or GUS mRNA expression occurred in the regenerated lines transformed with either of the two gusAINT oligo target sequences (26-nt and 19-nt). RNAi-induced silencing was achieved in banana, both at transient and stable level, resulting in significant reduction of gene expression and enzyme activity. The success of silencing was dependent on the targeted region of the target gene. The successful generation of transgenic ECS for second transformation with (an)other construct(s) can be of value for functional genomics research in banana.

Performance of Leak Compensation in All-Age ICU Ventilators During Volume-Targeted Neonatal Ventilation: A Lung Model Study.

PubMed

Itagaki, Taiga; Bennett, Desmond J; Chenelle, Christopher T; Fisher, Daniel F; Kacmarek, Robert M

2017-01-01

Volume-targeted ventilation is increasingly used in low birthweight infants because of the potential for reducing volutrauma and avoiding hypocapnea. However, it is not known what level of air leak is acceptable during neonatal volume-targeted ventilation when leak compensation is activated concurrently. Four ICU ventilators (Servo-i, PB980, V500, and Avea) were compared in available invasive volume-targeted ventilation modes (pressure control continuous spontaneous ventilation [PC-CSV] and pressure control continuous mandatory ventilation [PC-CMV]). The Servo-i and PB980 were tested with (+) and without (-) their proximal flow sensor. The V500 and Avea were tested with their proximal flow sensor as indicated by their manufacturers. An ASL 5000 lung model was used to simulate 4 neonatal scenarios (body weight 0.5, 1, 2, and 4 kg). The ASL 5000 was ventilated via an endotracheal tube with 3 different leaks. Two minutes of data were collected after each change in leak level, and the asynchrony index was calculated. Tidal volume (V T ) before and after the change in leak was assessed. The differences in delivered V T between before and after the change in leak were within ±5% in all scenarios with the PB980 (-/+) and V500. With the Servo-i (-/+), baseline V T was ≥10% greater than set V T during PC-CSV, and delivered V T markedly changed with leak. The Avea demonstrated persistent high V T in all leak scenarios. Across all ventilators, the median asynchrony index was 1% (interquartile range 0-27%) in PC-CSV and 1.8% (0-45%) in PC-CMV. The median asynchrony index was significantly higher in the Servo-i (-/+) than in the PB980 (-/+) and V500 in 1 and 2 kg scenarios during PC-CSV and PC-CMV. The PB980 and V500 were the only ventilators to acclimate to all leak scenarios and achieve targeted V T . Further clinical investigation is needed to validate the use of leak compensation during neonatal volume-targeted ventilation. Copyright © 2017 by Daedalus Enterprises.

Automatically detect and track infrared small targets with kernel Fukunaga-Koontz transform and Kalman prediction.

PubMed

Liu, Ruiming; Liu, Erqi; Yang, Jie; Zeng, Yong; Wang, Fanglin; Cao, Yuan

2007-11-01

Fukunaga-Koontz transform (FKT), stemming from principal component analysis (PCA), is used in many pattern recognition and image-processing fields. It cannot capture the higher-order statistical property of natural images, so its detection performance is not satisfying. PCA has been extended into kernel PCA in order to capture the higher-order statistics. However, thus far there have been no researchers who have definitely proposed kernel FKT (KFKT) and researched its detection performance. For accurately detecting potential small targets from infrared images, we first extend FKT into KFKT to capture the higher-order statistical properties of images. Then a framework based on Kalman prediction and KFKT, which can automatically detect and track small targets, is developed. Results of experiments show that KFKT outperforms FKT and the proposed framework is competent to automatically detect and track infrared point targets.

Automatically detect and track infrared small targets with kernel Fukunaga-Koontz transform and Kalman prediction

NASA Astrophysics Data System (ADS)

Liu, Ruiming; Liu, Erqi; Yang, Jie; Zeng, Yong; Wang, Fanglin; Cao, Yuan

2007-11-01

Fukunaga-Koontz transform (FKT), stemming from principal component analysis (PCA), is used in many pattern recognition and image-processing fields. It cannot capture the higher-order statistical property of natural images, so its detection performance is not satisfying. PCA has been extended into kernel PCA in order to capture the higher-order statistics. However, thus far there have been no researchers who have definitely proposed kernel FKT (KFKT) and researched its detection performance. For accurately detecting potential small targets from infrared images, we first extend FKT into KFKT to capture the higher-order statistical properties of images. Then a framework based on Kalman prediction and KFKT, which can automatically detect and track small targets, is developed. Results of experiments show that KFKT outperforms FKT and the proposed framework is competent to automatically detect and track infrared point targets.

Outlier and target detection in aerial hyperspectral imagery: a comparison of traditional and percentage occupancy hit or miss transform techniques

NASA Astrophysics Data System (ADS)

Young, Andrew; Marshall, Stephen; Gray, Alison

2016-05-01

The use of aerial hyperspectral imagery for the purpose of remote sensing is a rapidly growing research area. Currently, targets are generally detected by looking for distinct spectral features of the objects under surveillance. For example, a camouflaged vehicle, deliberately designed to blend into background trees and grass in the visible spectrum, can be revealed using spectral features in the near-infrared spectrum. This work aims to develop improved target detection methods, using a two-stage approach, firstly by development of a physics-based atmospheric correction algorithm to convert radiance into re ectance hyperspectral image data and secondly by use of improved outlier detection techniques. In this paper the use of the Percentage Occupancy Hit or Miss Transform is explored to provide an automated method for target detection in aerial hyperspectral imagery.

Under conditions of large geometric miss, tumor control probability can be higher for static gantry intensity-modulated radiation therapy compared to volume-modulated arc therapy for prostate cancer.

PubMed

Balderson, Michael; Brown, Derek; Johnson, Patricia; Kirkby, Charles

2016-01-01

The purpose of this work was to compare static gantry intensity-modulated radiation therapy (IMRT) with volume-modulated arc therapy (VMAT) in terms of tumor control probability (TCP) under scenarios involving large geometric misses, i.e., those beyond what are accounted for when margin expansion is determined. Using a planning approach typical for these treatments, a linear-quadratic-based model for TCP was used to compare mean TCP values for a population of patients who experiences a geometric miss (i.e., systematic and random shifts of the clinical target volume within the planning target dose distribution). A Monte Carlo approach was used to account for the different biological sensitivities of a population of patients. Interestingly, for errors consisting of coplanar systematic target volume offsets and three-dimensional random offsets, static gantry IMRT appears to offer an advantage over VMAT in that larger shift errors are tolerated for the same mean TCP. For example, under the conditions simulated, erroneous systematic shifts of 15mm directly between or directly into static gantry IMRT fields result in mean TCP values between 96% and 98%, whereas the same errors on VMAT plans result in mean TCP values between 45% and 74%. Random geometric shifts of the target volume were characterized using normal distributions in each Cartesian dimension. When the standard deviations were doubled from those values assumed in the derivation of the treatment margins, our model showed a 7% drop in mean TCP for the static gantry IMRT plans but a 20% drop in TCP for the VMAT plans. Although adding a margin for error to a clinical target volume is perhaps the best approach to account for expected geometric misses, this work suggests that static gantry IMRT may offer a treatment that is more tolerant to geometric miss errors than VMAT. Copyright © 2016 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

BSC-1 growth inhibitor transforms a mitogenic stimulus into a hypertrophic stimulus for renal proximal tubular cells: relationship to Na/sup +//H/sup +/ antiport activity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fine, L.G.; Holley, R.W.; Nasri, H.

Renal hypertrophy is characterized by an increase in cell size and protein content with minimal hyperplasia. The mechanisms of control of this pattern of cell growth have not been determined. The present studies examined whether the growth inhibitor elaborated by BSC-1 kidney epilethal cells (GI), which has nearly identical biological properties to transforming growth factor ..beta.. (TGF-..beta..), could transform a mitogenic stimulus into a hypertrophic stimulus for rabbit renal proximal tubular cells in primary culture. Insulin plus hydrocortisone increased the amount of protein per cell, cell volume, and (/sup 3/H)thymidine incorporation at 24 and 48 hr in these cells. Whenmore » added together with insulin plus hydrocortisone, GI/TGF-..beta.. inhibited the stimulatory effect of these mitogens on (/sup 3/H)thymidine incorporation but did not block the increase in protein per cell and cell volume - i.e., the cells underwent hypertrophy. The fact that this pattern persisted for 48 hr indicated that GI/TGF-..beta.. exerted a prolonged inhibitory effect on mitogenic-stimulated DNA synthesis rather than delaying its onset. Amiloride-sensitive Na/sup +/ uptake using /sup 22/Na/sup +/ as a tracer, correlated with protein per cell and cell volume rather than with DNA synthesis. These studies indicate that the control of cell size may be regulated by autocrine mechanisms mediated by the elaboration of growth inhibitory factors that alter the pattern of the growth response to mitogens.« less

MRI Volume Fusion Based on 3D Shearlet Decompositions.

PubMed

Duan, Chang; Wang, Shuai; Wang, Xue Gang; Huang, Qi Hong

2014-01-01

Nowadays many MRI scans can give 3D volume data with different contrasts, but the observers may want to view various contrasts in the same 3D volume. The conventional 2D medical fusion methods can only fuse the 3D volume data layer by layer, which may lead to the loss of interframe correlative information. In this paper, a novel 3D medical volume fusion method based on 3D band limited shearlet transform (3D BLST) is proposed. And this method is evaluated upon MRI T2* and quantitative susceptibility mapping data of 4 human brains. Both the perspective impression and the quality indices indicate that the proposed method has a better performance than conventional 2D wavelet, DT CWT, and 3D wavelet, DT CWT based fusion methods.

Target volume motion during anal cancer image guided radiotherapy using cone-beam computed tomography.

PubMed

Brooks, Corrinne J; Bernier, Laurence; Hansen, Vibeke N; Tait, Diana M

2018-05-01

Literature regarding image-guidance and interfractional motion of the anal canal (AC) during anal cancer radiotherapy is sparse. This study investigates interfractional AC motion during anal cancer radiotherapy. Bone matched cone beam CT (CBCT) images were acquired for 20 patients receiving anal cancer radiotherapy allowing population systematic and random error calculations. 12 were selected to investigate interfractional AC motion. Primary anal gross tumour volume and clinical target volume (CTVa) were contoured on each CBCT. CBCT CTVa volumes were compared to planning CTVa. CBCT CTVa volumes were combined into a CBCT-CTVa envelope for each patient. Maximum distortion between each orthogonal border of the planning CTVa and CBCT-CTVa envelope was measured. Frequency, volume and location of CBCT-CTVa envelope beyond the planning target volume (PTVa) was analysed. Population systematic and random errors were 1 and 3 mm respectively. 112 CBCTs were analysed in the interfractional motion study. CTVa varied between each imaging session particularly T location patients of anorectal origin. CTVa border expansions ≥ 1 cm were seen inferiorly, anteriorly, posteriorly and left direction. The CBCT-CTVa envelope fell beyond the PTVa ≥ 50% imaging sessions (n = 5). Of these CBCT CTVa distortions beyond PTVa, 44% and 32% were in the upper and lower thirds of PTVa respectively. The AC is susceptible to volume changes and shape deformations. Care must be taken when calculating or considering reducing the PTV margin to the anus. Advances in knowledge: Within a limited field of research, this study provides further knowledge of how the AC deforms during anal cancer radiotherapy.

Comparison of Dose Decrement from Intrafraction Motion for Prone and Supine Prostate Radiotherapy

PubMed Central

Olsen, Jeffrey; Parikh, Parag J; Watts, Michael; Noel, Camille E; Baker, Kenneth W; Santanam, Lakshmi; Michalski, Jeff M

2012-01-01

Background and Purpose Dose effects of intrafraction motion during prone prostate radiotherapy are unknown. We compared prone and supine treatment using real-time tracking data to model dose coverage. Material and Methods Electromagnetic tracking data was analyzed for 10 patients treated prone, and 15 treated supine, with IMRT for localized prostate cancer. Plans were generated using 0, 3, and 5 mm PTV expansions. Manual beam-hold interventions were applied to reposition the patient when translations exceeded a predetermined threshold. A custom software application (SWIFTER) used intrafraction tracking data acquired during beam-on to model delivered prostate dose, by applying rigid body transformations to the prostate structure contoured at simulation within the planned dose cloud. The delivered minimum prostate dose as a percentage of planned dose (Dmin%), and prostate volume covered by the prescription dose as a percentage of the planned volume (VRx%) were compared for prone and supine treatment. Results Dmin% was reduced for prone treatment for 0 (p=0.02) and 3 mm (p=0.03) PTV margins. VRx% was reduced for prone treatment only for 0 mm margins (p=0.002). No significant differences were found using 5 mm margins. Conclusions Intrafraction motion has a greater impact on target coverage for prone compared to supine prostate radiotherapy. PTV margins of 3 mm or less correlate with a significant decrease in delivered dose for prone treatment. PMID:22809590

Comparison of dose decrement from intrafraction motion for prone and supine prostate radiotherapy.

PubMed

Olsen, Jeffrey R; Parikh, Parag J; Watts, Michael; Noel, Camille E; Baker, Kenneth W; Santanam, Lakshmi; Michalski, Jeff M

2012-08-01

Dose effects of intrafraction motion during prone prostate radiotherapy are unknown. We compared prone and supine treatment using real-time tracking data to model dose coverage. Electromagnetic tracking data were analyzed for 10 patients treated prone, and 15 treated supine, with IMRT for localized prostate cancer. Plans were generated using 0 mm, 3 mm, and 5mm PTV expansions. Manual beam-hold interventions were applied to reposition the patient when translations exceeded a predetermined threshold. A custom software application (SWIFTER) used intrafraction tracking data acquired during beam-on model delivered prostate dose, by applying rigid body transformations to the prostate structure contoured at simulation within the planned dose cloud. The delivered minimum prostate dose as a percentage of planned dose (Dmin%), and prostate volume covered by the prescription dose as a percentage of the planned volume (VRx%) were compared for prone and supine treatment. Dmin% was reduced for prone treatment for 0 (p=0.02) and 3 mm (p=0.03) PTV margins. VRx% was reduced for prone treatment only for 0mm margins (p=0.002). No significant differences were found using 5 mm margins. Intrafraction motion has a greater impact on target coverage for prone compared to supine prostate radiotherapy. PTV margins of 3 mm or less correlate with a significant decrease in delivered dose for prone treatment. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

[Comparison of planning quality and delivery efficiency between volumetric modulated arc therapy and dynamic intensity modulated radiation therapy for nasopharyngeal carcinoma with more than 4 prescribed dose levels].

PubMed

Jia, Pengfei; Xu, Jun; Zhou, Xiaoxi; Chen, Jian; Tang, Lemin

2017-12-01

The aim of this study is to compare the planning quality and delivery efficiency between dynamic intensity modulated radiation therapy (d-IMRT) and dual arc volumetric modulated arc therapy (VMAT) systematically for nasopharyngeal carcinoma (NPC) patients with multi-prescribed dose levels, and to analyze the correlations between target volumes and plan qualities. A total of 20 patients of NPC with 4-5 prescribed dose levels to achieve simultaneous integrated boost (SIB) treated by sliding window d-IMRT in our department from 2014 to 2015 were re-planned with dual arc VMAT. All optimization objectives for each VMAT plan were as the same as the corresponding d-IMRT plan. The dose parameters for targets and organ at risk (OAR), the delivery time and monitor units (MU) in two sets of plans were compared respectively. The treatment accuracy was tested by three dimensional dose validation system. Finally, the correlations between the difference of planning quality and the volume of targets were discussed. The conform indexes (CIs) of planning target volumes (PTVs) in VMAT plans were obviously high than those in d-IMRT plans ( P < 0.05), but no significant correlations between the difference of CIs and the volume of targets were discovered ( P > 0.05). The target coverage and heterogeneity indexes (HIs) of PTV 1 and PGTV nd and PTV 3 in two sets of plans were consistent. The doses of PTV 2 decreased and HIs were worse in VMAT plans. VMAT could provide better spinal cord and brainstem sparing, but increase mean dose of parotids. The average number of MUs and delivery time for d-IMRT were 3.32 and 2.19 times of that for VMAT. The γ-index (3 mm, 3%) analysis for each plans was more than 97% in COMPASS ® measurement for quality assurance (QA). The results show that target dose coverages in d-IMRT and VMAT plans are similar for NPC with multi-prescribed dose levels. VMAT could improve the the CIs of targets, but reduce the dose to the target volume in neck except for PGTV nd . The biggest advantages of VMAT over d-IMRT are delivery efficiency and QA.

Mitigation of arsenic-induced acquired cancer phenotype in prostate cancer stem cells by miR-143 restoration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ngalame, Ntube N.O., E-mail: ngalamenn@niehs.nih.g

Inorganic arsenic, an environmental contaminant and a human carcinogen is associated with prostate cancer. Emerging evidence suggests that cancer stem cells (CSCs) are the driving force of carcinogenesis. Chronic arsenic exposure malignantly transforms the human normal prostate stem/progenitor cell (SC) line, WPE-stem to arsenic-cancer SCs (As-CSCs), through unknown mechanisms. MicroRNAs (miRNAs) are small, non-coding RNAs that negatively regulate gene expression at the posttranscriptional level. In prior work, miR-143 was markedly downregulated in As-CSCs, suggesting a role in arsenic-induced malignant transformation. In the present study, we investigated whether loss of miR-143 expression is important in arsenic-induced transformation of prostate SCs. Restorationmore » of miR-143 in As-CSCs was achieved by lentivirus-mediated miR-143 overexpression. Cells were assessed bi-weekly for up to 30 weeks to examine mitigation of cancer phenotype. Secreted matrix metalloproteinase (MMP) activity was increased by arsenic-induced malignant transformation, but miR-143 restoration decreased secreted MMP-2 and MMP-9 enzyme activities compared with scramble controls. Increased cell proliferation and apoptotic resistance, two hallmarks of cancer, were decreased upon miR-143 restoration. Increased apoptosis was associated with decreased BCL2 and BCL-XL expression. miR-143 restoration dysregulated the expression of SC/CSC self-renewal genes including NOTCH-1, BMI-1, OCT4 and ABCG2. The anticancer effects of miR-143 overexpression appeared to be mediated by targeting and inhibiting LIMK1 protein, and the phosphorylation of cofilin, a LIMK1 substrate. These findings clearly show that miR-143 restoration mitigated multiple cancer characteristics in the As-CSCs, suggesting a potential role in arsenic-induced transformation of prostate SCs. Thus, miR-143 is a potential biomarker and therapeutic target for arsenic-induced prostate cancer. - Highlights: • Chronic arsenic exposure malignantly transforms human prostate stem cells (SCs) to arsenic-cancer SCs via unknown mechanisms. • miR-143 was several fold downregulated in the arsenic-cancer SCs (As-CSCs), suggesting a likely role in transformation. • miR-143 restoration reduced cancer characteristics in the As-CSC, suggesting a role in arsenic-induced SC transformation. • miR-143 appears to exert its anticancer effect by inhibiting expression and activity of LIMK1, its predicted gene target. • These findings suggest miR-143 is a potential biomarker and therapeutic target for arsenic-induced prostate cancer.« less

A performance-oriented power transformer design methodology using multi-objective evolutionary optimization

PubMed Central

Adly, Amr A.; Abd-El-Hafiz, Salwa K.

2014-01-01

Transformers are regarded as crucial components in power systems. Due to market globalization, power transformer manufacturers are facing an increasingly competitive environment that mandates the adoption of design strategies yielding better performance at lower costs. In this paper, a power transformer design methodology using multi-objective evolutionary optimization is proposed. Using this methodology, which is tailored to be target performance design-oriented, quick rough estimation of transformer design specifics may be inferred. Testing of the suggested approach revealed significant qualitative and quantitative match with measured design and performance values. Details of the proposed methodology as well as sample design results are reported in the paper. PMID:26257939

A performance-oriented power transformer design methodology using multi-objective evolutionary optimization.

PubMed

Adly, Amr A; Abd-El-Hafiz, Salwa K

2015-05-01

Transformers are regarded as crucial components in power systems. Due to market globalization, power transformer manufacturers are facing an increasingly competitive environment that mandates the adoption of design strategies yielding better performance at lower costs. In this paper, a power transformer design methodology using multi-objective evolutionary optimization is proposed. Using this methodology, which is tailored to be target performance design-oriented, quick rough estimation of transformer design specifics may be inferred. Testing of the suggested approach revealed significant qualitative and quantitative match with measured design and performance values. Details of the proposed methodology as well as sample design results are reported in the paper.

Risk Assessment of Power System considering the CPS of Transformers

NASA Astrophysics Data System (ADS)

Zhou, Long; Peng, Zewu; Liu, Xindong; Li, Canbing; Chen, Can

2018-02-01

This paper constructs a risk assessment framework of power system for device-level information security, analyzes the typical protection configuration of power transformers, and takes transformer gas protection and differential protection as examples to put forward a method that analyzes the cyber security in electric power system, which targets transformer protection parameters. We estimate the risk of power system accounting for the cyber security of transformer through utilizing Monte Carlo method and two indexes, which are the loss of load probability and the expected demand not supplied. The proposed approach is tested with IEEE 9 bus system and IEEE 118 bus system.

[Radiotherapy volume delineation based on (18F)-fluorodeoxyglucose positron emission tomography for locally advanced or inoperable oesophageal cancer].

PubMed

Encaoua, J; Abgral, R; Leleu, C; El Kabbaj, O; Caradec, P; Bourhis, D; Pradier, O; Schick, U

2017-06-01

To study the impact on radiotherapy planning of an automatically segmented target volume delineation based on ( 18 F)-fluorodeoxy-D-glucose (FDG)-hybrid positron emission tomography-computed tomography (PET-CT) compared to a manually delineation based on computed tomography (CT) in oesophageal carcinoma patients. Fifty-eight patients diagnosed with oesophageal cancer between September 2009 and November 2014 were included. The majority had squamous cell carcinoma (84.5 %), and advanced stage (37.9 % were stade IIIA) and 44.8 % had middle oesophageal lesion. Gross tumour volumes were retrospectively defined based either manually on CT or automatically on coregistered PET/CT images using three different threshold methods: standard-uptake value (SUV) of 2.5, 40 % of maximum intensity and signal-to-background ratio. Target volumes were compared in length, volume and using the index of conformality. Radiotherapy plans to the dose of 50Gy and 66Gy using intensity-modulated radiotherapy were generated and compared for both data sets. Planification target volume coverage and doses delivered to organs at risk (heart, lung and spinal cord) were compared. The gross tumour volume based manually on CT was significantly longer than that automatically based on signal-to-background ratio (6.4cm versus 5.3cm; P<0.008). Doses to the lungs (V20, D mean ), heart (V40), and spinal cord (D max ) were significantly lower on plans using the PTV SBR . The PTV SBR coverage was statistically better than the PTV CT coverage on both plans. (50Gy: P<0.0004 and 66Gy: P<0.0006). The automatic PET segmentation algorithm based on the signal-to-background ratio method for the delineation of oesophageal tumours is interesting, and results in better target volume coverage and decreased dose to organs at risk. This may allow dose escalation up to 66Gy to the gross tumour volume. Copyright © 2017 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

Locoregional control after intensity-modulated radiotherapy for nasopharyngeal carcinoma with an anatomy-based target definition.

PubMed

Kawashima, Mitsuhiko; Ariji, Takaki; Kameoka, Satoru; Ueda, Takashi; Kohno, Ryosuke; Nishio, Teiji; Arahira, Satoko; Motegi, Atsushi; Zenda, Sadamoto; Akimoto, Tetsuo; Tahara, Makoto; Hayashi, Ryuichi

2013-12-01

The objective of the study was to evaluate locoregional control after intensity-modulated radiotherapy for nasopharyngeal cancer using a target definition along with anatomical boundaries. Forty patients with biopsy-proven squamous cell or non-keratinizing carcinoma of the nasopharynx who underwent intensity-modulated radiotherapy between April 2006 and November 2009 were reviewed. There were 10 females and 30 males with a median age of 48 years (range, 17-74 years). More than half of the patients had T3/4 (n = 21) and/or N2/3 (n = 24) disease. Intensity-modulated radiotherapy was administered as 70 Gy/33 fractions with or without concomitant chemotherapy. The clinical target volume was contoured along with muscular fascia or periosteum, and the prescribed radiotherapy dose was determined for each anatomical compartment and lymph node level in the head and neck. One local recurrence was observed at Meckel's cave on the periphery of the high-risk clinical target volume receiving a total dose of <63 Gy. Otherwise, six locoregional failures were observed within irradiated volume receiving 70 Gy. Local and nodal control rates at 3 years were 91 and 89%, respectively. Adverse events were acceptable, and 25 (81%) of 31 patients who were alive without recurrence at 2 years had xerostomia of ≤Grade 1. The overall survival rate at 3 years was 87%. Target definition along with anatomically defined boundaries was feasible without compromise of the therapeutic ratio. It is worth testing this method further to minimize the unnecessary irradiated volume and to standardize the target definition in intensity-modulated radiotherapy for nasopharyngeal cancer.

Australasian Gastrointestinal Trials Group (AGITG) Contouring Atlas and Planning Guidelines for Intensity-Modulated Radiotherapy in Anal Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ng, Michael, E-mail: mng@radoncvic.com.au; Leong, Trevor; University of Melbourne

2012-08-01

Purpose: To develop a high-resolution target volume atlas with intensity-modulated radiotherapy (IMRT) planning guidelines for the conformal treatment of anal cancer. Methods and Materials: A draft contouring atlas and planning guidelines for anal cancer IMRT were prepared at the Australasian Gastrointestinal Trials Group (AGITG) annual meeting in September 2010. An expert panel of radiation oncologists contoured an anal cancer case to generate discussion on recommendations regarding target definition for gross disease, elective nodal volumes, and organs at risk (OARs). Clinical target volume (CTV) and planning target volume (PTV) margins, dose fractionation, and other IMRT-specific issues were also addressed. A steeringmore » committee produced the final consensus guidelines. Results: Detailed contouring and planning guidelines and a high-resolution atlas are provided. Gross tumor and elective target volumes are described and pictorially depicted. All elective regions should be routinely contoured for all disease stages, with the possible exception of the inguinal and high pelvic nodes for select, early-stage T1N0. A 20-mm CTV margin for the primary, 10- to 20-mm CTV margin for involved nodes and a 7-mm CTV margin for the elective pelvic nodal groups are recommended, while respecting anatomical boundaries. A 5- to 10-mm PTV margin is suggested. When using a simultaneous integrated boost technique, a dose of 54 Gy in 30 fractions to gross disease and 45 Gy to elective nodes with chemotherapy is appropriate. Guidelines are provided for OAR delineation. Conclusion: These consensus planning guidelines and high-resolution atlas complement the existing Radiation Therapy Oncology Group (RTOG) elective nodal ano-rectal atlas and provide additional anatomic, clinical, and technical instructions to guide radiation oncologists in the planning and delivery of IMRT for anal cancer.« less

A New Suggestion for the Radiation Target Volume After a Subtotal Gastrectomy in Patients With Stomach Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nam, Heerim; Lim, Do Hoon; Kim, Sung

2008-06-01

Purpose: To compare treatment results between the use of two different radiation fields including and excluding remnant stomach and suggest new target volumes excluding remnant stomach after subtotal gastrectomy (STG) in patients with stomach cancer. Methods and Materials: We retrospectively analyzed 291 patients treated with adjuvant chemoradiotherapy after STG and D2 dissection at the Samsung Medical Center, Seoul, South Korea. Eighty-three patients registered from 1995 to 1997 underwent irradiation according to the INT 0116 protocol that recommended the inclusion of remnant stomach within the target volume (Group A). After this period, we excluded remnant stomach from the target volume formore » 208 patients (Group B). Median follow-up was 67 months. Results: Treatment failure developed in 93 patients (32.0%). Local and regional recurrence rates for Group A vs. Group B were 10.8% vs. 5.3% (p = not significant) and 9.6% vs. 6.3% (p = not significant), and recurrence rates for remnant stomach were 7.2% vs. 1.4% (p = 0.018), respectively. Overall and disease-free survival rates were not different between the two groups. Grade 3 or 4 vomiting and diarrhea developed more frequently in Group A than Group B (4.8% vs. 1.4% and 6.0% vs. 1.9%, respectively; p = 0.012; p < 0.001). Conclusion: Exclusion of remnant stomach from the radiation field had no effect on failure rates or survival, and a low complication rate occurred in patients treated excluding remnant stomach. We suggest that remnant stomach be excluded from the radiation target volume for patients with stomach cancer who undergo STG and D2 dissection.« less

Dose gradient curve: A new tool for evaluating dose gradient

PubMed Central

Choi, Young Eun

2018-01-01

Purpose Stereotactic radiotherapy, which delivers an ablative high radiation dose to a target volume for maximum local tumor control, requires a rapid dose fall-off outside the target volume to prevent extensive damage to nearby normal tissue. Currently, there is no tool to comprehensively evaluate the dose gradient near the target volume. We propose the dose gradient curve (DGC) as a new tool to evaluate the quality of a treatment plan with respect to the dose fall-off characteristics. Methods The average distance between two isodose surfaces was represented by the dose gradient index (DGI) estimated by a simple equation using the volume and surface area of isodose levels. The surface area was calculated by mesh generation and surface triangulation. The DGC was defined as a plot of the DGI of each dose interval as a function of the dose. Two types of DGCs, differential and cumulative, were generated. The performance of the DGC was evaluated using stereotactic radiosurgery plans for virtual targets. Results Over the range of dose distributions, the dose gradient of each dose interval was well-characterized by the DGC in an easily understandable graph format. Significant changes in the DGC were observed reflecting the differences in planning situations and various prescription doses. Conclusions The DGC is a rational method for visualizing the dose gradient as the average distance between two isodose surfaces; the shorter the distance, the steeper the dose gradient. By combining the DGC with the dose-volume histogram (DVH) in a single plot, the DGC can be utilized to evaluate not only the dose gradient but also the target coverage in routine clinical practice. PMID:29698471

DOE Office of Scientific and Technical Information (OSTI.GOV)

Balderson, Michael, E-mail: michael.balderson@rmp.uhn.ca; Brown, Derek; Johnson, Patricia

The purpose of this work was to compare static gantry intensity-modulated radiation therapy (IMRT) with volume-modulated arc therapy (VMAT) in terms of tumor control probability (TCP) under scenarios involving large geometric misses, i.e., those beyond what are accounted for when margin expansion is determined. Using a planning approach typical for these treatments, a linear-quadratic–based model for TCP was used to compare mean TCP values for a population of patients who experiences a geometric miss (i.e., systematic and random shifts of the clinical target volume within the planning target dose distribution). A Monte Carlo approach was used to account for themore » different biological sensitivities of a population of patients. Interestingly, for errors consisting of coplanar systematic target volume offsets and three-dimensional random offsets, static gantry IMRT appears to offer an advantage over VMAT in that larger shift errors are tolerated for the same mean TCP. For example, under the conditions simulated, erroneous systematic shifts of 15 mm directly between or directly into static gantry IMRT fields result in mean TCP values between 96% and 98%, whereas the same errors on VMAT plans result in mean TCP values between 45% and 74%. Random geometric shifts of the target volume were characterized using normal distributions in each Cartesian dimension. When the standard deviations were doubled from those values assumed in the derivation of the treatment margins, our model showed a 7% drop in mean TCP for the static gantry IMRT plans but a 20% drop in TCP for the VMAT plans. Although adding a margin for error to a clinical target volume is perhaps the best approach to account for expected geometric misses, this work suggests that static gantry IMRT may offer a treatment that is more tolerant to geometric miss errors than VMAT.« less

Potential dosimetric benefits of adaptive tumor tracking over the internal target volume concept for stereotactic body radiation therapy of pancreatic cancer.

PubMed

Karava, Konstantina; Ehrbar, Stefanie; Riesterer, Oliver; Roesch, Johannes; Glatz, Stefan; Klöck, Stephan; Guckenberger, Matthias; Tanadini-Lang, Stephanie

2017-11-09

Radiotherapy for pancreatic cancer has two major challenges: (I) the tumor is adjacent to several critical organs and, (II) the mobility of both, the tumor and its surrounding organs at risk (OARs). A treatment planning study simulating stereotactic body radiation therapy (SBRT) for pancreatic tumors with both the internal target volume (ITV) concept and the tumor tracking approach was performed. The two respiratory motion-management techniques were compared in terms of doses to the target volume and organs at risk. Two volumetric-modulated arc therapy (VMAT) treatment plans (5 × 5 Gy) were created for each of the 12 previously treated pancreatic cancer patients, one using the ITV concept and one the tumor tracking approach. To better evaluate the overall dose delivered to the moving tumor volume, 4D dose calculations were performed on four-dimensional computed tomography (4DCT) scans. The resulting planning target volume (PTV) size for each technique was analyzed. Target and OAR dose parameters were reported and analyzed for both 3D and 4D dose calculation. Tumor motion ranged from 1.3 to 11.2 mm. Tracking led to a reduction of PTV size (max. 39.2%) accompanied with significant better tumor coverage (p<0.05, paired Wilcoxon signed rank test) both in 3D and 4D dose calculations and improved organ at risk sparing. Especially for duodenum, stomach and liver, the mean dose was significantly reduced (p<0.05) with tracking for 3D and 4D dose calculations. By using an adaptive tumor tracking approach for respiratory-induced pancreatic motion management, a significant reduction in PTV size can be achieved, which subsequently facilitates treatment planning, and improves organ dose sparing. The dosimetric benefit of tumor tracking is organ and patient-specific.

Postoperative radiation in esophageal squamous cell carcinoma and target volume delineation

PubMed Central

Zhu, Yingming; Li, Minghuan; Kong, Li; Yu, Jinming

2016-01-01

Esophageal cancer is the sixth leading cause of cancer death worldwide, and patients who are treated with surgery alone, without neoadjuvant therapies, experience frequent relapses. Whether postoperative therapies could reduce the recurrence or improve overall survival is still controversial for these patients. The purpose of our review is to figure out the value of postoperative adjuvant therapy and address the disputes about target volume delineation according to published data. Based on the evidence of increased morbidity and disadvantages on patient survival caused by postoperative chemotherapy or radiotherapy (RT) alone provided by studies in the early 1990s, the use of postoperative adjuvant therapies in cases of esophageal squamous cell carcinoma has diminished substantially and has been replaced gradually by neoadjuvant chemoradiation. With advances in surgery and RT, accumulating evidence has recently rekindled interest in the delivery of postoperative RT or chemoradiotherapy in patients with stage T3/T4 or N1 (lymph node positive) carcinomas after radical surgery. However, due to complications with the standard radiation field, a nonconforming modified field has been adopted in most studies. Therefore, we analyze different field applications and provide suggestions on the optimization of the radiation field based on the major sites of relapse and the surgical non-clearance area. For upper and middle thoracic esophageal carcinomas, the bilateral supraclavicular and superior mediastinal areas remain common sites of recurrence and should be encompassed within the clinical target volume. In contrast, a consensus has yet to be reached regarding lower thoracic esophageal carcinomas; the “standard” clinical target volume is still recommended. Further studies of larger sample sizes should focus on different recurrence patterns, categorized by tumor locations, refined classifications, and differing molecular biology, to provide more information on the delineation of target volumes. PMID:27471393

Poster — Thur Eve — 32: Stereotactic Body Radiation Therapy for Peripheral Lung Lesion: Treatment Planning and Quality Assurance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wan, Shuying; Oliver, Michael; Wang, Xiaofang

2014-08-15

Stereotactic body radiation therapy (SBRT), due to its high precision for target localizing, has become widely used to treat tumours at various locations, including the lungs. Lung SBRT program was started at our institution a year ago. Eighteen patients with peripheral lesions up to 3 cm diameter have been treated with 48 Gy in 4 fractions. Based on four-dimensional computed tomography (4DCT) simulation, internal target volume (ITV) was delineated to encompass the respiratory motion of the lesion. A margin of 5 mm was then added to create the planning target volume (PTV) for setup uncertainties. There was no expansion frommore » gross tumour volume (GTV) to clinical target volume (CTV). Pinnacle 9.6 was used as the primary treatment planning system. Volumetric modulated arc therapy (VMAT) technique, with one or two coplanar arcs, generally worked well. For quality assurance (QA), each plan was exported to Eclipse 10 and dose calculation was repeated. Dose volume histograms (DVHs) of the targets and organs at risk (OARs) were then compared between the two treatment planning systems. Winston-Lutz tests were carried out as routine machine QA. Patient-specific QA included ArcCheck measurement with an insert, where an ionization chamber was placed at the centre to measure dose at the isocenter. For the first several patients, and subsequently for the plans with extremely strong modulation, Gafchromic film dosimetry was also employed. For each patient, a mock setup was scheduled prior to treatments. Daily pre- and post-CBCT were acquired for setup and assessment of intra-fractional motion, respectively.« less

An analytical approach for the calculation of stress-intensity factors in transformation-toughened ceramics

NASA Astrophysics Data System (ADS)

Müller, W. H.

1990-12-01

Stress-induced transformation toughening in Zirconia-containing ceramics is described analytically by means of a quantitative model: A Griffith crack which interacts with a transformed, circular Zirconia inclusion. Due to its volume expansion, a ZrO2-particle compresses its flanks, whereas a particle in front of the crack opens the flanks such that the crack will be attracted and finally absorbed. Erdogan's integral equation technique is applied to calculate the dislocation functions and the stress-intensity-factors which correspond to these situations. In order to derive analytical expressions, the elastic constants of the inclusion and the matrix are assumed to be equal.

Magnetostructural phase transformations in Tb 1-x Mn 2

DOE PAGES

Zou, Junding; Paudyal, Durga; Liu, Jing; ...

2015-01-16

Magnetism and phase transformations in non-stoichiometric Tb 1-xMn 2 (x = 0.056, 0.039) have been studied as functions of temperature and magnetic field using magnetization, heat capacity, and X-ray powder diffraction measurements. Lowering the temperature, the compounds sequentially order ferrimagnetically and antiferromagnetically, and finally, exhibit spin reorientation transitions. Moreover, these structural distortions from room temperature cubic to low temperature rhombohedral structures occur at T N, and are accompanied by large volume changes reaching ~-1.27% and -1.42%, respectively. First principles electronic structure calculations confirm the phase transformation from the ferrimagnetic cubic structure to the antiferromagnetic rhombohedral structure in TbMn 2.

Impact of FDG-PET on radiation therapy volume delineation in non-small-cell lung cancer.

PubMed

Bradley, Jeffrey; Thorstad, Wade L; Mutic, Sasa; Miller, Tom R; Dehdashti, Farrokh; Siegel, Barry A; Bosch, Walter; Bertrand, Rudi J

2004-05-01

Locoregional failure remains a significant problem for patients receiving definitive radiation therapy alone or combined with chemotherapy for non-small-cell lung cancer (NSCLC). Positron emission tomography (PET) with [(18)F]fluoro-2-deoxy-d-glucose (FDG) has proven to be a valuable diagnostic and staging tool for NSCLC. This prospective study was performed to determine the impact of treatment simulation with FDG-PET and CT on radiation therapy target volume definition and toxicity profiles by comparison to simulation with computed tomography (CT) scanning alone. Twenty-six patients with Stages I-III NSCLC were studied. Each patient underwent sequential CT and FDG-PET simulation on the same day. Immobilization devices used for both simulations included an alpha cradle, a flat tabletop, 6 external fiducial markers, and a laser positioning system. A radiation therapist participated in both simulations to reproduce the treatment setup. Both the CT and fused PET/CT image data sets were transferred to the radiation treatment planning workstation for contouring. Each FDG-PET study was reviewed with the interpreting nuclear radiologist before tumor volumes were contoured. The fused PET/CT images were used to develop the three-dimensional conformal radiation therapy (3DCRT) plan. A second physician, blinded to the results of PET, contoured the gross tumor volumes (GTV) and planning target volumes (PTV) from the CT data sets, and these volumes were used to generate mock 3DCRT plans. The PTV was defined by a 10-mm margin around the GTV. The two 3DCRT plans for each patient were compared with respect to the GTV, PTV, mean lung dose, volume of normal lung receiving > or =20 Gy (V20), and mean esophageal dose. The FDG-PET findings altered the AJCC TNM stage in 8 of 26 (31%) patients; 2 patients were diagnosed with metastatic disease based on FDG-PET and received palliative radiation therapy. Of the 24 patients who were planned with 3DCRT, PET clearly altered the radiation therapy volume in 14 (58%), as follows. PET helped to distinguish tumor from atelectasis in all 3 patients with atelectasis. Unsuspected nodal disease was detected by PET in 10 patients, and 1 patient had a separate tumor focus detected within the same lobe of the lung. Increases in the target volumes led to increases in the mean lung dose, V20, and mean esophageal dose. Decreases in the target volumes in the patients with atelectasis led to decreases in these normal-tissue toxicity parameters. Radiation targeting with fused FDG-PET and CT images resulted in alterations in radiation therapy planning in over 50% of patients by comparison with CT targeting. The increasing availability of integrated PET/CT units will facilitate the use of this technology for radiation treatment planning. A confirmatory multicenter, cooperative group trial is planned within the Radiation Therapy Oncology Group.

Analytical investigation for Lorentz forces effect on nanofluid Marangoni boundary layer hydrothermal behavior using HAM

NASA Astrophysics Data System (ADS)

Sheikholeslami, M.; Ganji, D. D.

2017-12-01

In this paper, semi analytical approach is applied to investigate nanofluid Marangoni convection in presence of magnetic field. Koo-Kleinstreuer-Li model is taken into account to simulate nanofluid properties. Homotopy analysis method is utilized to solve the final ordinary equations which are obtained from similarity transformation. Roles of Hartmann number and nanofluid volume fraction are presented graphically. Results show that temperature augments with rise of nanofluid volume fraction. Impact of nanofluid volume fraction on normal velocity is more than tangential velocity. Temperature gradient enhances with rise of magnetic number.

Althaea rosea Cavanil and Plantago major L. suppress neoplastic cell transformation through the inhibition of epidermal growth factor receptor kinase.

PubMed

Choi, Eun-Sun; Cho, Sung-Dae; Shin, Ji-Ae; Kwon, Ki Han; Cho, Nam-Pyo; Shim, Jung-Hyun

2012-10-01

For thousands of years in Asia, Althaea rosea Cavanil (ARC) and Plantago major L. (PML) have been used as powerful non-toxic therapeutic agents that inhibit inflammation. However, the anticancer mechanisms and molecular targets of ARC and PML are poorly understood, particularly in epidermal growth factor (EGF)-induced neoplastic cell transformation. The aim of this study was to evaluate the chemopreventive effects and mechanisms of the methanol extracts from ARC (MARC) and PML (MPML) in EGF-induced neoplastic cell transformation of JB6 P+ mouse epidermal cells using an MTS assay, anchorage-independent cell transformation assay and western blotting. Our results showed that MARC and MPML significantly suppressed neoplastic cell transformation by inhibiting the kinase activity of the EGF receptor (EGFR). The activation of EGFR by EGF was suppressed by MARC and MPML treatment in EGFR(+/+) cells, but not in EGFR(-/-) cells. In addition, MARC and MPML inhibited EGF-induced cell proliferation in EGFR-expressing murine embryonic fibroblasts (EGFR(+/+)). These results strongly indicate that EGFR targeting by MARC and MPML may be a good strategy for chemopreventive or chemotherapeutic applications.

Microstructural fingerprints of phase transitions in shock-loaded iron

NASA Astrophysics Data System (ADS)

Wang, S. J.; Sui, M. L.; Chen, Y. T.; Lu, Q. H.; Ma, E.; Pei, X. Y.; Li, Q. Z.; Hu, H. B.

2013-01-01

The complex structural transformation in crystals under static pressure or shock loading has been a subject of long-standing interest to materials scientists and physicists. The polymorphic transformation is of particular importance for iron (Fe), due to its technological and sociological significance in the development of human civilization, as well as its prominent presence in the earth's core. The martensitic transformation α-->ɛ (bcc-->hcp) in iron under shock-loading, due to its reversible and transient nature, requires non-trivial detective work to uncover its occurrence. Here we reveal refined microstructural fingerprints, needle-like colonies and three sets of {112}<111> twins with a threefold symmetry, with tell-tale features that are indicative of two sequential martensitic transformations in the reversible α-->ɛ phase transition, even though no ɛ is retained in the post-shock samples. The signature orientation relationships are consistent with previously-proposed transformation mechanisms, and the unique microstructural fingerprints enable a quantitative assessment of the volume fraction transformed.

SU-C-19A-07: Influence of Immobilization On Plan Robustness in the Treatment of Head and Neck Cancer with IMPT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bues, M; Anand, A; Liu, W

2014-06-15

Purpose: We evaluated the effect of interposing immobilization devices into the beam's path on the robustness of a head and neck plan. Methods: An anthropomorphic head phantom was placed into a preliminary prototype of a specialized head and neck immobilization device for proton beam therapy. The device consists of a hard low density shell, a custom mold insert, and thermoplastic mask to immobilize the patient's head in the shell. This device was provided by CIVCO Medical Solutions for the purpose of evaluation of suitability for proton beam therapy. See Figure 1. Two pairs of treatment plans were generated. The firstmore » plan in each pair was a reference plan including only the anthropomorphic phantom, and the second plan in each pair included the immobilization device. In all other respects the plans within the pair were identical. Results: In the case of the simple plan the degradation of plan robustness was found to be clinically insignificant. In this case, target coverage in the worst case scenario was reduced from 95% of the target volume receiving 96.5% of prescription dose to 95% of the target volume receiving 96.3% of prescription dose by introducing the immobilization device. In the case of the complex plan, target coverage of the boost volume in the worst case scenario was reduced from 95% of the boost target volume receiving 97% of prescription dose to 95% of the boost target volume receiving 83% of prescription dose by introducing the immobilization device. See Figure 2. Conclusion: Immobilization devices may have a deleterious effect on plan robustness. Evaluation of the preliminary prototype revealed a variable impact on the plan robustness depending of the complexity of the case. Brian Morse is an employee of CIVCO Medical Solutions.« less

High-Frequency Jet Ventilation for Complete Target Immobilization and Reduction of Planning Target Volume in Stereotactic High Single-Dose Irradiation of Stage I Non-Small Cell Lung Cancer and Lung Metastases

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fritz, Peter, E-mail: p.h.fritz@t-online.d; Kraus, Hans-Joerg; Muehlnickel, Werner

2010-09-01

Purpose: To demonstrate the feasibility of complete target immobilization by means of high-frequency jet ventilation (HFJV); and to show that the saving of planning target volume (PTV) on the stereotactic body radiation therapy (SBRT) under HFJV, compared with SBRT with respiratory motion, can be predicted with reliable accuracy by computed tomography (CT) scans at peak inspiration phase. Methods and Materials: A comparison regarding different methods for defining the PTV was carried out in 22 patients with tumors that clearly moved with respiration. A movement span of the gross tumor volume (GTV) was defined by fusing respiration-correlated CT scans. The PTVmore » enclosed the GTV positions with a safety margin throughout the breathing cycle. To create a PTV from CT scans acquired under HFJV, the same margins were drawn around the immobilized target. In addition, peak inspiration phase CT images (PIP-CTs) were used to approximate a target immobilized by HFJV. Results: The resulting HFJV-PTVs were between 11.6% and 45.4% smaller than the baseline values calculated as respiration-correlated CT-PTVs (median volume reduction, 25.4%). Tentative planning by means of PIP-CT PTVs predicted that in 19 of 22 patients, use of HFJV would lead to a reduction in volume of {>=}20%. Using this threshold yielded a positive predictive value of 0.89, as well as a sensitivity of 0.94 and a specificity of 0.5. Conclusions: In all patients, SBRT under HFJV provided a reliable immobilization of the GTVs and achieved a reduction in PTVs, regardless of patient compliance. Tentative planning facilitated the selection of patients who could better undergo radiation in respiratory standstill, both with greater accuracy and lung protection.« less

Volumetric modulated arc therapy versus step-and-shoot intensity modulated radiation therapy in the treatment of large nerve perineural spread to the skull base: a comparative dosimetric planning study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gorayski, Peter; Fitzgerald, Rhys; Barry, Tamara

Cutaneous squamous cell carcinoma with large nerve perineural (LNPN) infiltration of the base of skull is a radiotherapeutic challenge given the complex target volumes to nearby organs at risk (OAR). A comparative planning study was undertaken to evaluate dosimetric differences between volumetric modulated arc therapy (VMAT) versus intensity modulated radiation therapy (IMRT) in the treatment of LNPN. Five consecutive patients previously treated with IMRT for LNPN were selected. VMAT plans were generated for each case using the same planning target volumes (PTV), dose prescriptions and OAR constraints as IMRT. Comparative parameters used to assess target volume coverage, conformity and homogeneitymore » included V95 of the PTV (volume encompassed by the 95% isodose), conformity index (CI) and homogeneity index (HI). In addition, OAR maximum point doses, V20, V30, non-target tissue (NTT) point max doses, NTT volume above reference dose, monitor units (MU) were compared. IMRT and VMAT plans generated were comparable for CI (P = 0.12) and HI (P = 0.89). VMAT plans achieved better V95 (P = < 0.001) and reduced V20 and V30 by 652 cubic centimetres (cc) (28.5%) and 425.7 cc (29.1%), respectively. VMAT increased MU delivered by 18% without a corresponding increase in NTT dose. Compared with IMRT plans for LNPN, VMAT achieved comparable HI and CI.« less

Simultaneous integrated vs. sequential boost in VMAT radiotherapy of high-grade gliomas.

PubMed

Farzin, Mostafa; Molls, Michael; Astner, Sabrina; Rondak, Ina-Christine; Oechsner, Markus

2015-12-01

In 20 patients with high-grade gliomas, we compared two methods of planning for volumetric-modulated arc therapy (VMAT): simultaneous integrated boost (SIB) vs. sequential boost (SEB). The investigation focused on the analysis of dose distributions in the target volumes and the organs at risk (OARs). After contouring the target volumes [planning target volumes (PTVs) and boost volumes (BVs)] and OARs, SIB planning and SEB planning were performed. The SEB method consisted of two plans: in the first plan the PTV received 50 Gy in 25 fractions with a 2-Gy dose per fraction. In the second plan the BV received 10 Gy in 5 fractions with a dose per fraction of 2 Gy. The doses of both plans were summed up to show the total doses delivered. In the SIB method the PTV received 54 Gy in 30 fractions with a dose per fraction of 1.8 Gy, while the BV received 60 Gy in the same fraction number but with a dose per fraction of 2 Gy. All of the OARs showed higher doses (Dmax and Dmean) in the SEB method when compared with the SIB technique. The differences between the two methods were statistically significant in almost all of the OARs. Analysing the total doses of the target volumes we found dose distributions with similar homogeneities and comparable total doses. Our analysis shows that the SIB method offers advantages over the SEB method in terms of sparing OARs.

Internal jugular and vertebral vein volume flow in patients with clinically isolated syndrome or mild multiple sclerosis and healthy controls: results from a prospective sonographer-blinded study.

PubMed

Chambers, Brian; Chambers, Jayne; Churilov, Leonid; Cameron, Heather; Macdonell, Richard

2014-09-01

We evaluated internal jugular vein and vertebral vein volume flow using ultrasound, in patients with clinically isolated syndrome or mild multiple sclerosis and controls, to determine whether volume flow was different between the two groups. In patients and controls, internal jugular vein volume flow increased from superior to inferior segments, consistent with recruitment from collateral veins. Internal jugular vein and vertebral vein volume flow were greater on the right in supine and sitting positions. Internal jugular vein volume flow was higher in the supine posture. Vertebral vein volume flow was higher in the sitting posture. Regression analyses of cube root transformed volume flow data, adjusted for supine/sitting, right/left and internal jugular vein/vertebral vein, revealed no significant difference in volume flow in patients compared to controls. Our findings further refute the concept of venous obstruction as a causal factor in the pathogenesis of multiple sclerosis. Control volume flow data may provide useful normative reference values. © The Author(s) 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Quantitative prediction of phase transformations in silicon during nanoindentation

NASA Astrophysics Data System (ADS)

Zhang, Liangchi; Basak, Animesh

2013-08-01

This paper establishes the first quantitative relationship between the phases transformed in silicon and the shape characteristics of nanoindentation curves. Based on an integrated analysis using TEM and unit cell properties of phases, the volumes of the phases emerged in a nanoindentation are formulated as a function of pop-out size and depth of nanoindentation impression. This simple formula enables a fast, accurate and quantitative prediction of the phases in a nanoindentation cycle, which has been impossible before.

Energy Barriers and Hysteresis in Martensitic Phase Transformations

DTIC Science & Technology

2008-08-01

glacial acetic acid (CH3COOH) and 10-15% perchloric acid (HCLO4) by volume, the cathode was stainless steel , the anode was stainless steel or Ti, the...Submitted to Acta Materialia Energy barriers and hysteresis in martensitic phase transformations Zhiyong Zhang, Richard D. James and Stefan Müller...hysteresis based on the growth from a small scale of fully developed austenite martensite needles. In this theory the energy of the transition layer plays a

Transforming a Traditional Hands-On Activity into an Enquiry Activity to Foster More In-Depth Understanding of the Concept of Density

ERIC Educational Resources Information Center

Lee, Yeung Chung; Kwok, Ping Wai

2010-01-01

Traditional methods used to teach the concept of density that employ solid objects of different masses and volumes can be supplemented by enquiry activities in which students vary the mass-to-volume ratio of the same object to test ideas about density and flotation. A simple substance, Blu-Tack, is an ideal material to use in this case. The…

Critical dose and toxicity index of organs at risk in radiotherapy: Analyzing the calculated effects of modified dose fractionation in non–small cell lung cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pedicini, Piernicola, E-mail: ppiern@libero.it; Strigari, Lidia; Benassi, Marcello

2014-04-01

To increase the efficacy of radiotherapy for non–small cell lung cancer (NSCLC), many schemes of dose fractionation were assessed by a new “toxicity index” (I), which allows one to choose the fractionation schedules that produce less toxic treatments. Thirty-two patients affected by non resectable NSCLC were treated by standard 3-dimensional conformal radiotherapy (3DCRT) with a strategy of limited treated volume. Computed tomography datasets were employed to re plan by simultaneous integrated boost intensity-modulated radiotherapy (IMRT). The dose distributions from plans were used to test various schemes of dose fractionation, in 3DCRT as well as in IMRT, by transforming the dose-volumemore » histogram (DVH) into a biological equivalent DVH (BDVH) and by varying the overall treatment time. The BDVHs were obtained through the toxicity index, which was defined for each of the organs at risk (OAR) by a linear quadratic model keeping an equivalent radiobiological effect on the target volume. The less toxic fractionation consisted in a severe/moderate hyper fractionation for the volume including the primary tumor and lymph nodes, followed by a hypofractionation for the reduced volume of the primary tumor. The 3DCRT and IMRT resulted, respectively, in 4.7% and 4.3% of dose sparing for the spinal cord, without significant changes for the combined-lungs toxicity (p < 0.001). Schedules with reduced overall treatment time (accelerated fractionations) led to a 12.5% dose sparing for the spinal cord (7.5% in IMRT), 8.3% dose sparing for V{sub 20} in the combined lungs (5.5% in IMRT), and also significant dose sparing for all the other OARs (p < 0.001). The toxicity index allows to choose fractionation schedules with reduced toxicity for all the OARs and equivalent radiobiological effect for the tumor in 3DCRT, as well as in IMRT, treatments of NSCLC.« less

Secondary Students' Accounts of Carbon-Transforming Processes before and after Instruction

ERIC Educational Resources Information Center

Onyancha, Kennedy M.; Anderson, Charles W.

2012-01-01

The purpose of this study is to examine the extent to which more targeted instruction is helpful in eliciting students' scientific explanations of six selected carbon-transforming processes of combustion, cross processes, decomposition, growth, photosynthesis and respiration. We also examined these students' accounts regarding the corresponding…

Novel Platform for MRI-Guided Convection-Enhanced Delivery of Therapeutics: Preclinical Validation in Nonhuman Primate Brain

PubMed Central

Richardson, R. Mark; Kells, Adrian P.; Martin, Alastair J.; Larson, Paul S.; Starr, Philip A.; Piferi, Peter G.; Bates, Geoffrey; Tansey, Lisa; Rosenbluth, Kathryn H.; Bringas, John R.; Berger, Mitchel S.; Bankiewicz, Krystof S.

2011-01-01

Background/Aims A skull-mounted aiming device and integrated software platform has been developed for MRI-guided neurological interventions. In anticipation of upcoming gene therapy clinical trials, we adapted this device for real-time convection-enhanced delivery of therapeutics via a custom-designed infusion cannula. The targeting accuracy of this delivery system and the performance of the infusion cannula were validated in nonhuman primates. Methods Infusions of gadoteridol were delivered to multiple brain targets and the targeting error was determined for each cannula placement. Cannula performance was assessed by analyzing gadoteridol distributions and by histological analysis of tissue damage. Results The average targeting error for all targets (n = 11) was 0.8 mm (95% CI = 0.14). For clinically relevant volumes, the distribution volume of gadoteridol increased as a linear function (R2 = 0.97) of the infusion volume (average slope = 3.30, 95% CI = 0.2). No infusions in any target produced occlusion, cannula reflux or leakage from adjacent tracts, and no signs of unexpected tissue damage were observed. Conclusions This integrated delivery platform allows real-time convection-enhanced delivery to be performed with a high level of precision, predictability and safety. This approach may improve the success rate for clinical trials involving intracerebral drug delivery by direct infusion. PMID:21494065

Transformable DNA Nanocarriers for Plasma Membrane Targeted Delivery of Cytokine

PubMed Central

Sun, Wujin; Ji, Wenyan; Hu, Quanyin; Yu, Jicheng; Wang, Chao; Qian, Chenggen; Hochu, Gabrielle; Gu, Zhen

2016-01-01

Direct delivery of cytokines using nanocarriers holds great promise for cancer therapy. However, the nanometric scale of the vehicles made them susceptible to size-dependent endocytosis, reducing the plasma membrane-associated apoptosis signalling. Herein, we report a tumor microenvironment-responsive and transformable nanocarrier for cell membrane targeted delivery of cytokine. This formulation is comprised of a phospholipase A2 (PLA2) degradable liposome as a shell, and complementary DNA nanostructures (designated as nanoclews) decorated with cytokines as the cores. Utilizing the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) as a model cytokine, we demonstrate that the TRAIL loaded DNA nanoclews are capable of transforming into nanofibers after PLA2 activation. The nanofibers with micro-scaled lengths efficiently present the loaded TRAIL to death receptors on the cancer cell membrane and amplified the apoptotic signalling with reduced TRAIL internalization. PMID:27131597

Relationships Between the Phase Transformation Kinetics, Texture Evolution, and Microstructure Development in a 304L Stainless Steel Under Biaxial Loading Conditions: Synchrotron X-ray and Electron Backscatter Diffraction Studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cakmak, Ercan; Choo, Hahn; Kang, Jun-Yun

2015-02-11

The relationships between the martensitic phase transformation kinetics, texture evolution, and the microstructure development in the parent austenite phase were studied for a 304L stainless steel that exhibits the transformation-induced plasticity effect under biaxial loading conditions at ambient temperature. The applied loading paths included: pure torsion, simultaneous biaxial torsion/tension, simultaneous biaxial torsion/compression, and stepwise loading of tension followed by torsion (i.e., first loading by uniaxial tension and then by pure torsion in sequence). Synchrotron X-ray and electron backscatter diffraction techniques were used to measure the evolution of the phase fractions, textures, and microstructures as a function of the applied strains.more » The influence of loading character and path on the changes in martensitic phase transformation kinetics is discussed in the context of (1) texture-transformation relationship and the preferred transformation of grains belonging to certain texture components over the others, (2) effects of axial strains on shear band evolutions, and (3) volume changes associated with martensitic transformation.« less

Noncommutative Yang-Mills from equivalence of star products

NASA Astrophysics Data System (ADS)

Jurčo, B.; Schupp, P.

2000-05-01

It is shown that the transformation between ordinary and noncommutative Yang-Mills theory as formulated by Seiberg and Witten is due to the equivalence of certain star products on the D-brane world-volume.

EPA Science Matters Newsletter: Volume 2, Number 3

EPA Pesticide Factsheets

What began as a blueprint for designing safer chemical products and processes has, after two decades, not only transformed the field of chemistry but also given us the tools to build a sustainable future.

A statistical model for analyzing the rotational error of single isocenter for multiple targets technique.

PubMed

Chang, Jenghwa

2017-06-01

To develop a statistical model that incorporates the treatment uncertainty from the rotational error of the single isocenter for multiple targets technique, and calculates the extra PTV (planning target volume) margin required to compensate for this error. The random vector for modeling the setup (S) error in the three-dimensional (3D) patient coordinate system was assumed to follow a 3D normal distribution with a zero mean, and standard deviations of σ x , σ y , σ z . It was further assumed that the rotation of clinical target volume (CTV) about the isocenter happens randomly and follows a three-dimensional (3D) independent normal distribution with a zero mean and a uniform standard deviation of σ δ . This rotation leads to a rotational random error (R), which also has a 3D independent normal distribution with a zero mean and a uniform standard deviation of σ R equal to the product of σδπ180 and dI⇔T, the distance between the isocenter and CTV. Both (S and R) random vectors were summed, normalized, and transformed to the spherical coordinates to derive the Chi distribution with three degrees of freedom for the radial coordinate of S+R. PTV margin was determined using the critical value of this distribution for a 0.05 significance level so that 95% of the time the treatment target would be covered by the prescription dose. The additional PTV margin required to compensate for the rotational error was calculated as a function of σ R and dI⇔T. The effect of the rotational error is more pronounced for treatments that require high accuracy/precision like stereotactic radiosurgery (SRS) or stereotactic body radiotherapy (SBRT). With a uniform 2-mm PTV margin (or σ x = σ y = σ z = 0.715 mm), a σ R = 0.328 mm will decrease the CTV coverage probability from 95.0% to 90.9%, or an additional 0.2-mm PTV margin is needed to prevent this loss of coverage. If we choose 0.2 mm as the threshold, any σ R > 0.328 mm will lead to an extra PTV margin that cannot be ignored, and the maximal σ δ that can be ignored is 0.45° (or 0.0079 rad ) for dI⇔T = 50 mm or 0.23° (or 0.004 rad ) for dI⇔T = 100 mm. The rotational error cannot be ignored for high-accuracy/-precision treatments like SRS/SBRT, particularly when the distance between the isocenter and target is large. © 2017 American Association of Physicists in Medicine.

The performance of the progressive resolution optimizer (PRO) for RapidArc planning in targets with low-density media.

PubMed

Kan, Monica W K; Leung, Lucullus H T; Yu, Peter K N

2013-11-04

A new version of progressive resolution optimizer (PRO) with an option of air cavity correction has been implemented for RapidArc volumetric-modulated arc therapy (RA). The purpose of this study was to compare the performance of this new PRO with the use of air cavity correction option (PRO10_air) against the one without the use of the air cavity correction option (PRO10_no-air) for RapidArc planning in targets with low-density media of different sizes and complexities. The performance of PRO10_no-air and PRO10_air was initially compared using single-arc plans created for four different simple heterogeneous phantoms with virtual targets and organs at risk. Multiple-arc planning of 12 real patients having nasopharyngeal carcinomas (NPC) and ten patients having non-small cell lung cancer (NSCLC) were then performed using the above two options for further comparison. Dose calculations were performed using both the Acuros XB (AXB) algorithm with the dose to medium option and the analytical anisotropic algorithm (AAA). The effect of using intermediate dose option after the first optimization cycle in PRO10_air and PRO10_no-air was also investigated and compared. Plans were evaluated and compared using target dose coverage, critical organ sparing, conformity index, and dose homogeneity index. For NSCLC cases or cases for which large volumes of low-density media were present in or adjacent to the target volume, the use of the air cavity correction option in PRO10 was shown to be beneficial. For NPC cases or cases for which small volumes of both low- and high-density media existed in the target volume, the use of air cavity correction in PRO10 did not improve the plan quality. Based on the AXB dose calculation results, the use of PRO10_air could produce up to 18% less coverage to the bony structures of the planning target volumes for NPC cases. When the intermediate dose option in PRO10 was used, there was negligible difference observed in plan quality between optimizations with and without using the air cavity correction option.

Rapid update of discrete Fourier transform for real-time signal processing

NASA Astrophysics Data System (ADS)

Sherlock, Barry G.; Kakad, Yogendra P.

2001-10-01

In many identification and target recognition applications, the incoming signal will have properties that render it amenable to analysis or processing in the Fourier domain. In such applications, however, it is usually essential that the identification or target recognition be performed in real time. An important constraint upon real-time processing in the Fourier domain is the time taken to perform the Discrete Fourier Transform (DFT). Ideally, a new Fourier transform should be obtained after the arrival of every new data point. However, the Fast Fourier Transform (FFT) algorithm requires on the order of N log2 N operations, where N is the length of the transform, and this usually makes calculation of the transform for every new data point computationally prohibitive. In this paper, we develop an algorithm to update the existing DFT to represent the new data series that results when a new signal point is received. Updating the DFT in this way uses less computational order by a factor of log2 N. The algorithm can be modified to work in the presence of data window functions. This is a considerable advantage, because windowing is often necessary to reduce edge effects that occur because the implicit periodicity of the Fourier transform is not exhibited by the real-world signal. Versions are developed in this paper for use with the boxcar window, the split triangular, Hanning, Hamming, and Blackman windows. Generalization of these results to 2D is also presented.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ahmed, Raef S.; Shen, Sui; Ove, Roger

We wanted to describe a technique for the implementation of intensity-modulated radiotherapy (IMRT) with a real-time position monitor (RPM) respiratory gating system for the treatment of pleural space with intact lung. The technique is illustrated by a case of pediatric osteosarcoma, metastatic to the pleura of the right lung. The patient was simulated in the supine position where a breathing tracer and computed tomography (CT) scans synchronized at end expiration were acquired using the RPM system. The gated CT images were used to define target volumes and critical structures. Right pleural gated IMRT delivered at end expiration was prescribed tomore » a dose of 44 Gy, with 55 Gy delivered to areas of higher risk via simultaneous integrated boost (SIB) technique. IMRT was necessary to avoid exceeding the tolerance of intact lung. Although very good coverage of the target volume was achieved with a shell-shaped dose distribution, dose over the targets was relatively inhomogeneous. Portions of target volumes necessarily intruded into the right lung, the liver, and right kidney, limiting the degree of normal tissue sparing that could be achieved. The radiation doses to critical structures were acceptable and well tolerated. With intact lung, delivering a relatively high dose to the pleura with acceptable doses to surrounding normal tissues using respiratory gated pleural IMRT is feasible. Treatment delivery during a limited part of the respiratory cycle allows for reduced CT target volume motion errors, with reduction in the portion of the planning margin that accounts for respiratory motion, and subsequent increase in the therapeutic ratio.« less

Acoustic⁻Seismic Mixed Feature Extraction Based on Wavelet Transform for Vehicle Classification in Wireless Sensor Networks.

PubMed

Zhang, Heng; Pan, Zhongming; Zhang, Wenna

2018-06-07

An acoustic⁻seismic mixed feature extraction method based on the wavelet coefficient energy ratio (WCER) of the target signal is proposed in this study for classifying vehicle targets in wireless sensor networks. The signal was decomposed into a set of wavelet coefficients using the à trous algorithm, which is a concise method used to implement the wavelet transform of a discrete signal sequence. After the wavelet coefficients of the target acoustic and seismic signals were obtained, the energy ratio of each layer coefficient was calculated as the feature vector of the target signals. Subsequently, the acoustic and seismic features were merged into an acoustic⁻seismic mixed feature to improve the target classification accuracy after the acoustic and seismic WCER features of the target signal were simplified using the hierarchical clustering method. We selected the support vector machine method for classification and utilized the data acquired from a real-world experiment to validate the proposed method. The calculated results show that the WCER feature extraction method can effectively extract the target features from target signals. Feature simplification can reduce the time consumption of feature extraction and classification, with no effect on the target classification accuracy. The use of acoustic⁻seismic mixed features effectively improved target classification accuracy by approximately 12% compared with either acoustic signal or seismic signal alone.

Genome editing in Kluyveromyces and Ogataea yeasts using a broad-host-range Cas9/gRNA co-expression plasmid.

PubMed

Juergens, Hannes; Varela, Javier A; Gorter de Vries, Arthur R; Perli, Thomas; Gast, Veronica J M; Gyurchev, Nikola Y; Rajkumar, Arun S; Mans, Robert; Pronk, Jack T; Morrissey, John P; Daran, Jean-Marc G

2018-05-01

While CRISPR-Cas9-mediated genome editing has transformed yeast research, current plasmids and cassettes for Cas9 and guide-RNA expression are species specific. CRISPR tools that function in multiple yeast species could contribute to the intensifying research on non-conventional yeasts. A plasmid carrying a pangenomic origin of replication and two constitutive expression cassettes for Cas9 and ribozyme-flanked gRNAs was constructed. Its functionality was tested by analyzing inactivation of the ADE2 gene in four yeast species. In two Kluyveromyces species, near-perfect targeting (≥96%) and homologous repair (HR) were observed in at least 24% of transformants. In two Ogataea species, Ade- mutants were not observed directly after transformation, but prolonged incubation of transformed cells resulted in targeting efficiencies of 9% to 63% mediated by non-homologous end joining (NHEJ). In an Ogataea parapolymorpha ku80 mutant, deletion of OpADE2 mediated by HR was achieved, albeit at low efficiencies (<1%). Furthermore the expression of a dual polycistronic gRNA array enabled simultaneous interruption of OpADE2 and OpYNR1 demonstrating flexibility of ribozyme-flanked gRNA design for multiplexing. While prevalence of NHEJ prevented HR-mediated editing in Ogataea, such targeted editing was possible in Kluyveromyces. This broad-host-range CRISPR/gRNA system may contribute to exploration of Cas9-mediated genome editing in other Saccharomycotina yeasts.

Diffusion and perfusion weighted magnetic resonance imaging for tumor volume definition in radiotherapy of brain tumors.

PubMed

Guo, Lu; Wang, Gang; Feng, Yuanming; Yu, Tonggang; Guo, Yu; Bai, Xu; Ye, Zhaoxiang

2016-09-21

Accurate target volume delineation is crucial for the radiotherapy of tumors. Diffusion and perfusion magnetic resonance imaging (MRI) can provide functional information about brain tumors, and they are able to detect tumor volume and physiological changes beyond the lesions shown on conventional MRI. This review examines recent studies that utilized diffusion and perfusion MRI for tumor volume definition in radiotherapy of brain tumors, and it presents the opportunities and challenges in the integration of multimodal functional MRI into clinical practice. The results indicate that specialized and robust post-processing algorithms and tools are needed for the precise alignment of targets on the images, and comprehensive validations with more clinical data are important for the improvement of the correlation between histopathologic results and MRI parameter images.

Predicting Nonauditory Adverse Radiation Effects Following Radiosurgery for Vestibular Schwannoma: A Volume and Dosimetric Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hayhurst, Caroline; Monsalves, Eric; Bernstein, Mark

2012-04-01

Purpose: To define clinical and dosimetric predictors of nonauditory adverse radiation effects after radiosurgery for vestibular schwannoma treated with a 12 Gy prescription dose. Methods: We retrospectively reviewed our experience of vestibular schwannoma patients treated between September 2005 and December 2009. Two hundred patients were treated at a 12 Gy prescription dose; 80 had complete clinical and radiological follow-up for at least 24 months (median, 28.5 months). All treatment plans were reviewed for target volume and dosimetry characteristics; gradient index; homogeneity index, defined as the maximum dose in the treatment volume divided by the prescription dose; conformity index; brainstem; andmore » trigeminal nerve dose. All adverse radiation effects (ARE) were recorded. Because the intent of our study was to focus on the nonauditory adverse effects, hearing outcome was not evaluated in this study. Results: Twenty-seven (33.8%) patients developed ARE, 5 (6%) developed hydrocephalus, 10 (12.5%) reported new ataxia, 17 (21%) developed trigeminal dysfunction, 3 (3.75%) had facial weakness, and 1 patient developed hemifacial spasm. The development of edema within the pons was significantly associated with ARE (p = 0.001). On multivariate analysis, only target volume is a significant predictor of ARE (p = 0.001). There is a target volume threshold of 5 cm3, above which ARE are more likely. The treatment plan dosimetric characteristics are not associated with ARE, although the maximum dose to the 5th nerve is a significant predictor of trigeminal dysfunction, with a threshold of 9 Gy. The overall 2-year tumor control rate was 96%. Conclusions: Target volume is the most important predictor of adverse radiation effects, and we identified the significant treatment volume threshold to be 5 cm3. We also established through our series that the maximum tolerable dose to the 5th nerve is 9 Gy.« less