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Sample records for quantitative biology volume

  1. Cold Spring Harbor symposia on quantitative biology: Volume 51, Molecular biology of /ital Homo sapiens/

    International Nuclear Information System (INIS)

    1986-01-01

    This volume is the second part of a collection of papers submitted by the participants to the 1986 Cold Spring Harbor Symposium on Quantitative Biology entitled Molecular Biology of /ital Homo sapiens/. The 49 papers included in this volume are grouped by subject into receptors, human cancer genes, and gene therapy. (DT)

  2. Cold Spring Harbor symposia on quantitative biology: Volume 49, Recombination at the DNA level

    International Nuclear Information System (INIS)

    1984-01-01

    This volume contains full papers prepared by the participants to the 1984 Cold Springs Harbor Symposia on Quantitative Biology. This year's theme is entitled Recombination at the DNA level. The volume consists of 93 articles grouped into subject areas entitled chromosome mechanics, yeast systems, mammalian homologous recombination, transposons, mu, plant transposons/T4 recombination, topoisomerase, resolvase and gyrase, Escherichia coli general recombination, RecA, repair, leukaryotic enzymes, integration and excision of bacteriophage, site-specific recombination, and recombination in vitro

  3. Cold Spring Harbor symposia on quantitative biology. Volume XLVII, Part 1. Structures of DNA

    International Nuclear Information System (INIS)

    Anon.

    1983-01-01

    The proceedings for the 47th Annual Cold Spring Harbor Symposia on Quantitative Biology are presented. This symposium focused on the Structure of DNA. Topics presented covered research in the handedness of DNA, conformational analysis, chemically modified DNA, chemical synthesis of DNA, DNA-protein interactions, DNA within nucleosomes, DNA methylation, DNA replication, gyrases and topoisomerases, recombining and mutating DNA, transcription of DNA and its regulation, the organization of genes along DNA, repetitive DNA and pseudogenes, and origins of replication, centromeres, and teleomeres

  4. Applications of Microfluidics in Quantitative Biology.

    Science.gov (United States)

    Bai, Yang; Gao, Meng; Wen, Lingling; He, Caiyun; Chen, Yuan; Liu, Chenli; Fu, Xiongfei; Huang, Shuqiang

    2018-05-01

    Quantitative biology is dedicated to taking advantage of quantitative reasoning and advanced engineering technologies to make biology more predictable. Microfluidics, as an emerging technique, provides new approaches to precisely control fluidic conditions on small scales and collect data in high-throughput and quantitative manners. In this review, the authors present the relevant applications of microfluidics to quantitative biology based on two major categories (channel-based microfluidics and droplet-based microfluidics), and their typical features. We also envision some other microfluidic techniques that may not be employed in quantitative biology right now, but have great potential in the near future. © 2017 Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences. Biotechnology Journal Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  5. Molecular biology of Homo sapiens: Abstracts of papers presented at the 51st Cold Spring Harbor symposium on quantitative biology

    International Nuclear Information System (INIS)

    Watson, J.D.; Siniscalco, M.

    1986-01-01

    This volume contains abstracts of papers presented at the 51st Cold Springs Harbor Symposium on Quantitative Biology. The topic for this meeting was the ''Molecular Biology of Homo sapiens.'' Sessions were entitled Human Gene Map, Human Cancer Genes, Genetic Diagnosis, Human Evolution, Drugs Made Off Human Genes, Receptors, and Gene Therapy. (DT)

  6. Molecular biology of Homo sapiens: Abstracts of papers presented at the 51st Cold Spring Harbor symposium on quantitative biology

    Energy Technology Data Exchange (ETDEWEB)

    Watson, J.D.; Siniscalco, M.

    1986-01-01

    This volume contains abstracts of papers presented at the 51st Cold Springs Harbor Symposium on Quantitative Biology. The topic for this meeting was the ''Molecular Biology of Homo sapiens.'' Sessions were entitled Human Gene Map, Human Cancer Genes, Genetic Diagnosis, Human Evolution, Drugs Made Off Human Genes, Receptors, and Gene Therapy. (DT)

  7. Quantitative biological measurement in Transmission Electron Tomography

    International Nuclear Information System (INIS)

    Mantell, Judith M; Verkade, Paul; Arkill, Kenton P

    2012-01-01

    It has been known for some time that biological sections shrink in the transmission electron microscope from exposure to the electron beam. This phenomenon is especially important in Electron Tomography (ET). The effect on shrinkage of parameters such as embedding medium or sample type is less well understood. In addition anisotropic area shrinkage has largely been ignored. The intention of this study is to explore the shrinkage on a number of samples ranging in thickness from 200 nm to 500 nm. A protocol was developed to determine the shrinkage in area and thickness using the gold fiducials used in electron tomography. In brief: Using low dose philosophy on the section, a focus area was used prior to a separate virgin study area for a series of known exposures on a tilted sample. The shrinkage was determined by measurements on the gold beads from both sides of the section as determined by a confirmatory tomogram. It was found that the shrinkage in area (approximately to 90-95% of the original) and the thickness (approximately 65% of the original at most) agreed with pervious authors, but that a lmost all the shrinkage was in the first minute and that although the direction of the in-plane shrinkage (in x and y) was sometimes uneven the end result was consistent. It was observed, in general, that thinner samples showed more percentage shrinkage than thicker ones. In conclusion, if direct quantitative measurements are required then the protocol described should be used for all areas studied.

  8. Quantitative biological measurement in Transmission Electron Tomography

    Science.gov (United States)

    Mantell, Judith M.; Verkade, Paul; Arkill, Kenton P.

    2012-07-01

    It has been known for some time that biological sections shrink in the transmission electron microscope from exposure to the electron beam. This phenomenon is especially important in Electron Tomography (ET). The effect on shrinkage of parameters such as embedding medium or sample type is less well understood. In addition anisotropic area shrinkage has largely been ignored. The intention of this study is to explore the shrinkage on a number of samples ranging in thickness from 200 nm to 500 nm. A protocol was developed to determine the shrinkage in area and thickness using the gold fiducials used in electron tomography. In brief: Using low dose philosophy on the section, a focus area was used prior to a separate virgin study area for a series of known exposures on a tilted sample. The shrinkage was determined by measurements on the gold beads from both sides of the section as determined by a confirmatory tomogram. It was found that the shrinkage in area (approximately to 90-95% of the original) and the thickness (approximately 65% of the original at most) agreed with pervious authors, but that a lmost all the shrinkage was in the first minute and that although the direction of the in-plane shrinkage (in x and y) was sometimes uneven the end result was consistent. It was observed, in general, that thinner samples showed more percentage shrinkage than thicker ones. In conclusion, if direct quantitative measurements are required then the protocol described should be used for all areas studied.

  9. On the Edge of Mathematics and Biology Integration: Improving Quantitative Skills in Undergraduate Biology Education

    Science.gov (United States)

    Feser, Jason; Vasaly, Helen; Herrera, Jose

    2013-01-01

    In this paper, the authors describe how two institutions are helping their undergraduate biology students build quantitative competencies. Incorporation of quantitative skills and reasoning in biology are framed through a discussion of two cases that both concern introductory biology courses, but differ in the complexity of the mathematics and the…

  10. Abstracts of papers presented at the LVIII Cold Spring Harbor Symposium on quantitative Biology: DNA and chromosomes

    Energy Technology Data Exchange (ETDEWEB)

    1993-12-31

    This volume contains the abstracts of oral and poster presentations made at the LVIII Cold Spring Harbor Symposium on Quantitative Biology entitles DNA & Chromosomes. The meeting was held June 2--June 9, 1993 at Cold Spring Harbor, New York.

  11. Infusion of Quantitative and Statistical Concepts into Biology Courses Does Not Improve Quantitative Literacy

    Science.gov (United States)

    Beck, Christopher W.

    2018-01-01

    Multiple national reports have pushed for the integration of quantitative concepts into the context of disciplinary science courses. The aim of this study was to evaluate the quantitative and statistical literacy of biology students and explore learning gains when those skills were taught implicitly in the context of biology. I examined gains in…

  12. Quantitative stem cell biology: the threat and the glory.

    Science.gov (United States)

    Pollard, Steven M

    2016-11-15

    Major technological innovations over the past decade have transformed our ability to extract quantitative data from biological systems at an unprecedented scale and resolution. These quantitative methods and associated large datasets should lead to an exciting new phase of discovery across many areas of biology. However, there is a clear threat: will we drown in these rivers of data? On 18th July 2016, stem cell biologists gathered in Cambridge for the 5th annual Cambridge Stem Cell Symposium to discuss 'Quantitative stem cell biology: from molecules to models'. This Meeting Review provides a summary of the data presented by each speaker, with a focus on quantitative techniques and the new biological insights that are emerging. © 2016. Published by The Company of Biologists Ltd.

  13. Free radicals in biology. Volume II

    International Nuclear Information System (INIS)

    Pryor, W.A.

    1976-01-01

    This volume continues the treatment of topics in free radical biology and free radical pathology from Volume I. In the first chapter, pyridinyl radicals, radicals which are models for those derived from NAD, are discussed. Pyridinyl radicals can be synthesized and isolated and directly studied in a number of chemical systems. The next chapter treats the role of glutathione in the cell. It is becoming even more apparent that this vital thiol controls a large number of important cellular functions. The GSH/GSSG balance has recently been implicated as a control for cellular development; this balance also may be important in relaying the effects of oxidants from one site to another in the body. The next chapter outlines the reactions of singlet oxygen; some of these involve free radicals and some do not. This reactive intermediate appears to be important both in photochemical smog and in cellular chemistry where singlet oxygen is produced by nonphotochemical processes. The production of free radicals from dry tissues, a controversial area with conflicting claims is reviewed. The next chapter outlines the current status of the studies of photochemical smog. The next two chapters treat specific reactive materials which are present in smog. The first discusses the chemistry of nitrogen oxides and ozone. The second chapter treats the chemistry of the peroxyacyl nitrites. These compounds, although present in only small concentration, are among the most toxic components of smog. The last two chapters treat radiation damage to proteins and radiation protection and radical reactions produced by radiation in nucleic acids

  14. Automated force volume image processing for biological samples.

    Directory of Open Access Journals (Sweden)

    Pavel Polyakov

    2011-04-01

    Full Text Available Atomic force microscopy (AFM has now become a powerful technique for investigating on a molecular level, surface forces, nanomechanical properties of deformable particles, biomolecular interactions, kinetics, and dynamic processes. This paper specifically focuses on the analysis of AFM force curves collected on biological systems, in particular, bacteria. The goal is to provide fully automated tools to achieve theoretical interpretation of force curves on the basis of adequate, available physical models. In this respect, we propose two algorithms, one for the processing of approach force curves and another for the quantitative analysis of retraction force curves. In the former, electrostatic interactions prior to contact between AFM probe and bacterium are accounted for and mechanical interactions operating after contact are described in terms of Hertz-Hooke formalism. Retraction force curves are analyzed on the basis of the Freely Jointed Chain model. For both algorithms, the quantitative reconstruction of force curves is based on the robust detection of critical points (jumps, changes of slope or changes of curvature which mark the transitions between the various relevant interactions taking place between the AFM tip and the studied sample during approach and retraction. Once the key regions of separation distance and indentation are detected, the physical parameters describing the relevant interactions operating in these regions are extracted making use of regression procedure for fitting experiments to theory. The flexibility, accuracy and strength of the algorithms are illustrated with the processing of two force-volume images, which collect a large set of approach and retraction curves measured on a single biological surface. For each force-volume image, several maps are generated, representing the spatial distribution of the searched physical parameters as estimated for each pixel of the force-volume image.

  15. Quantitative X-ray microanalysis of biological specimens

    International Nuclear Information System (INIS)

    Roomans, G.M.

    1988-01-01

    Qualitative X-ray microanalysis of biological specimens requires an approach that is somewhat different from that used in the materials sciences. The first step is deconvolution and background subtraction on the obtained spectrum. The further treatment depends on the type of specimen: thin, thick, or semithick. For thin sections, the continuum method of quantitation is most often used, but it should be combined with an accurate correction for extraneous background. However, alternative methods to determine local mass should also be considered. In the analysis of biological bulk specimens, the ZAF-correction method appears to be less useful, primarily because of the uneven surface of biological specimens. The peak-to-local background model may be a more adequate method for thick specimens that are not mounted on a thick substrate. Quantitative X-ray microanalysis of biological specimens generally requires the use of standards that preferably should resemble the specimen in chemical and physical properties. Special problems in biological microanalysis include low count rates, specimen instability and mass loss, extraneous contributions to the spectrum, and preparative artifacts affecting quantitation. A relatively recent development in X-ray microanalysis of biological specimens is the quantitative determination of local water content

  16. Integrating quantitative thinking into an introductory biology course improves students' mathematical reasoning in biological contexts.

    Science.gov (United States)

    Hester, Susan; Buxner, Sanlyn; Elfring, Lisa; Nagy, Lisa

    2014-01-01

    Recent calls for improving undergraduate biology education have emphasized the importance of students learning to apply quantitative skills to biological problems. Motivated by students' apparent inability to transfer their existing quantitative skills to biological contexts, we designed and taught an introductory molecular and cell biology course in which we integrated application of prerequisite mathematical skills with biology content and reasoning throughout all aspects of the course. In this paper, we describe the principles of our course design and present illustrative examples of course materials integrating mathematics and biology. We also designed an outcome assessment made up of items testing students' understanding of biology concepts and their ability to apply mathematical skills in biological contexts and administered it as a pre/postcourse test to students in the experimental section and other sections of the same course. Precourse results confirmed students' inability to spontaneously transfer their prerequisite mathematics skills to biological problems. Pre/postcourse outcome assessment comparisons showed that, compared with students in other sections, students in the experimental section made greater gains on integrated math/biology items. They also made comparable gains on biology items, indicating that integrating quantitative skills into an introductory biology course does not have a deleterious effect on students' biology learning.

  17. Integrating Quantitative Thinking into an Introductory Biology Course Improves Students’ Mathematical Reasoning in Biological Contexts

    Science.gov (United States)

    Hester, Susan; Buxner, Sanlyn; Elfring, Lisa; Nagy, Lisa

    2014-01-01

    Recent calls for improving undergraduate biology education have emphasized the importance of students learning to apply quantitative skills to biological problems. Motivated by students’ apparent inability to transfer their existing quantitative skills to biological contexts, we designed and taught an introductory molecular and cell biology course in which we integrated application of prerequisite mathematical skills with biology content and reasoning throughout all aspects of the course. In this paper, we describe the principles of our course design and present illustrative examples of course materials integrating mathematics and biology. We also designed an outcome assessment made up of items testing students’ understanding of biology concepts and their ability to apply mathematical skills in biological contexts and administered it as a pre/postcourse test to students in the experimental section and other sections of the same course. Precourse results confirmed students’ inability to spontaneously transfer their prerequisite mathematics skills to biological problems. Pre/postcourse outcome assessment comparisons showed that, compared with students in other sections, students in the experimental section made greater gains on integrated math/biology items. They also made comparable gains on biology items, indicating that integrating quantitative skills into an introductory biology course does not have a deleterious effect on students’ biology learning. PMID:24591504

  18. Water volume quantitation using nuclear magnetic resonance imaging: application to cerebrospinal fluid

    International Nuclear Information System (INIS)

    Lecouffe, P.; Huglo, D.; Dubois, P.; Rousseau, J.; Marchandise, X.

    1990-01-01

    Quantitation in proton NMR imaging is applied to cerebrospinal fluid (CSF). Total intracranial CSF volume was measured from Condon's method: CSF signal was compared with distilled water standard signal in a single sagittal thick slice. Brain signal was reduced to minimum using a 5000/360/400 sequence. Software constraints did not permit easy implementing on imager and uniformity correction was performed on a microcomputer. Accuracy was better than 4%. Total intracranial CSF was found between 91 and 164 ml in 5 healthy volunteers. Extraventricular CSF quantitation appears very improved by this method, but planimetric methods seem better in order to quantify ventricular CSF. This technique is compared to total lung water measurement from proton density according to Mac Lennan's method. Water volume quantitation confirms ability of NMR imaging to quantify biologic parameters but image defects have to be known by strict quality control [fr

  19. A method for three-dimensional quantitative observation of the microstructure of biological samples

    Science.gov (United States)

    Wang, Pengfei; Chen, Dieyan; Ma, Wanyun; Wu, Hongxin; Ji, Liang; Sun, Jialin; Lv, Danyu; Zhang, Lu; Li, Ying; Tian, Ning; Zheng, Jinggao; Zhao, Fengying

    2009-07-01

    Contemporary biology has developed into the era of cell biology and molecular biology, and people try to study the mechanism of all kinds of biological phenomena at the microcosmic level now. Accurate description of the microstructure of biological samples is exigent need from many biomedical experiments. This paper introduces a method for 3-dimensional quantitative observation on the microstructure of vital biological samples based on two photon laser scanning microscopy (TPLSM). TPLSM is a novel kind of fluorescence microscopy, which has excellence in its low optical damage, high resolution, deep penetration depth and suitability for 3-dimensional (3D) imaging. Fluorescent stained samples were observed by TPLSM, and afterward the original shapes of them were obtained through 3D image reconstruction. The spatial distribution of all objects in samples as well as their volumes could be derived by image segmentation and mathematic calculation. Thus the 3-dimensionally and quantitatively depicted microstructure of the samples was finally derived. We applied this method to quantitative analysis of the spatial distribution of chromosomes in meiotic mouse oocytes at metaphase, and wonderful results came out last.

  20. Review of Department of Defense Education Activity (DODEA) Schools. Volume II: Quantitative Analysis of Educational Quality

    National Research Council Canada - National Science Library

    Anderson, Lowell

    2000-01-01

    This volume compiles, and presents in integrated form, IDA's quantitative analysis of educational quality provided by DoD's dependent schools, It covers the quantitative aspects of volume I in greater...

  1. Novel whole brain segmentation and volume estimation using quantitative MRI

    Energy Technology Data Exchange (ETDEWEB)

    West, J. [Linkoeping University, Radiation Physics, Department of Medical and Health Sciences, Faculty of Health Sciences, Linkoeping (Sweden); Linkoeping University, Center for Medical Imaging Science and Visualization (CMIV), Linkoeping (Sweden); SyntheticMR AB, Linkoeping (Sweden); Warntjes, J.B.M. [Linkoeping University, Center for Medical Imaging Science and Visualization (CMIV), Linkoeping (Sweden); SyntheticMR AB, Linkoeping (Sweden); Linkoeping University and Department of Clinical Physiology UHL, County Council of Oestergoetland, Clinical Physiology, Department of Medical and Health Sciences, Faculty of Health Sciences, Linkoeping (Sweden); Lundberg, P. [Linkoeping University, Center for Medical Imaging Science and Visualization (CMIV), Linkoeping (Sweden); Linkoeping University and Department of Radiation Physics UHL, County Council of Oestergoetland, Radiation Physics, Department of Medical and Health Sciences, Faculty of Health Sciences, Linkoeping (Sweden); Linkoeping University and Department of Radiology UHL, County Council of Oestergoetland, Radiology, Department of Medical and Health Sciences, Faculty of Health Sciences, Linkoeping (Sweden)

    2012-05-15

    Brain segmentation and volume estimation of grey matter (GM), white matter (WM) and cerebro-spinal fluid (CSF) are important for many neurological applications. Volumetric changes are observed in multiple sclerosis (MS), Alzheimer's disease and dementia, and in normal aging. A novel method is presented to segment brain tissue based on quantitative magnetic resonance imaging (qMRI) of the longitudinal relaxation rate R{sub 1}, the transverse relaxation rate R{sub 2} and the proton density, PD. Previously reported qMRI values for WM, GM and CSF were used to define tissues and a Bloch simulation performed to investigate R{sub 1}, R{sub 2} and PD for tissue mixtures in the presence of noise. Based on the simulations a lookup grid was constructed to relate tissue partial volume to the R{sub 1}-R{sub 2}-PD space. The method was validated in 10 healthy subjects. MRI data were acquired using six resolutions and three geometries. Repeatability for different resolutions was 3.2% for WM, 3.2% for GM, 1.0% for CSF and 2.2% for total brain volume. Repeatability for different geometries was 8.5% for WM, 9.4% for GM, 2.4% for CSF and 2.4% for total brain volume. We propose a new robust qMRI-based approach which we demonstrate in a patient with MS. (orig.)

  2. Novel whole brain segmentation and volume estimation using quantitative MRI

    International Nuclear Information System (INIS)

    West, J.; Warntjes, J.B.M.; Lundberg, P.

    2012-01-01

    Brain segmentation and volume estimation of grey matter (GM), white matter (WM) and cerebro-spinal fluid (CSF) are important for many neurological applications. Volumetric changes are observed in multiple sclerosis (MS), Alzheimer's disease and dementia, and in normal aging. A novel method is presented to segment brain tissue based on quantitative magnetic resonance imaging (qMRI) of the longitudinal relaxation rate R 1 , the transverse relaxation rate R 2 and the proton density, PD. Previously reported qMRI values for WM, GM and CSF were used to define tissues and a Bloch simulation performed to investigate R 1 , R 2 and PD for tissue mixtures in the presence of noise. Based on the simulations a lookup grid was constructed to relate tissue partial volume to the R 1 -R 2 -PD space. The method was validated in 10 healthy subjects. MRI data were acquired using six resolutions and three geometries. Repeatability for different resolutions was 3.2% for WM, 3.2% for GM, 1.0% for CSF and 2.2% for total brain volume. Repeatability for different geometries was 8.5% for WM, 9.4% for GM, 2.4% for CSF and 2.4% for total brain volume. We propose a new robust qMRI-based approach which we demonstrate in a patient with MS. (orig.)

  3. Biological characteristics of crucian by quantitative inspection method

    Science.gov (United States)

    Chu, Mengqi

    2015-04-01

    Biological characteristics of crucian by quantitative inspection method Through quantitative inspection method , the biological characteristics of crucian was preliminary researched. Crucian , Belongs to Cypriniformes, Cyprinidae, Carassius auratus, is a kind of main plant-eating omnivorous fish,like Gregarious, selection and ranking. Crucian are widely distributed, perennial water all over the country all have production. Determine the indicators of crucian in the experiment, to understand the growth, reproduction situation of crucian in this area . Using the measured data (such as the scale length ,scale size and wheel diameter and so on) and related functional to calculate growth of crucian in any one year.According to the egg shape, color, weight ,etc to determine its maturity, with the mean egg diameter per 20 eggs and the number of eggs per 0.5 grams, to calculate the relative and absolute fecundity of the fish .Measured crucian were female puberty. Based on the relation between the scale diameter and length and the information, linear relationship between crucian scale diameter and length: y=1.530+3.0649. From the data, the fertility and is closely relative to the increase of age. The older, the more mature gonad development. The more amount of eggs. In addition, absolute fecundity increases with the pituitary gland.Through quantitative check crucian bait food intake by the object, reveals the main food, secondary foods, and chance food of crucian ,and understand that crucian degree of be fond of of all kinds of bait organisms.Fish fertility with weight gain, it has the characteristics of species and populations, and at the same tmes influenced by the age of the individual, body length, body weight, environmental conditions (especially the nutrition conditions), and breeding habits, spawning times factors and the size of the egg. After a series of studies of crucian biological character, provide the ecological basis for local crucian's feeding, breeding

  4. Modeling Cancer Metastasis using Global, Quantitative and Integrative Network Biology

    DEFF Research Database (Denmark)

    Schoof, Erwin; Erler, Janine

    understanding of molecular processes which are fundamental to tumorigenesis. In Article 1, we propose a novel framework for how cancer mutations can be studied by taking into account their effect at the protein network level. In Article 2, we demonstrate how global, quantitative data on phosphorylation dynamics...... can be generated using MS, and how this can be modeled using a computational framework for deciphering kinase-substrate dynamics. This framework is described in depth in Article 3, and covers the design of KinomeXplorer, which allows the prediction of kinases responsible for modulating observed...... phosphorylation dynamics in a given biological sample. In Chapter III, we move into Integrative Network Biology, where, by combining two fundamental technologies (MS & NGS), we can obtain more in-depth insights into the links between cellular phenotype and genotype. Article 4 describes the proof...

  5. Quantitative measures of healthy aging and biological age

    Science.gov (United States)

    Kim, Sangkyu; Jazwinski, S. Michal

    2015-01-01

    Numerous genetic and non-genetic factors contribute to aging. To facilitate the study of these factors, various descriptors of biological aging, including ‘successful aging’ and ‘frailty’, have been put forth as integrative functional measures of aging. A separate but related quantitative approach is the ‘frailty index’, which has been operationalized and frequently used. Various frailty indices have been constructed. Although based on different numbers and types of health variables, frailty indices possess several common properties that make them useful across different studies. We have been using a frailty index termed FI34 based on 34 health variables. Like other frailty indices, FI34 increases non-linearly with advancing age and is a better indicator of biological aging than chronological age. FI34 has a substantial genetic basis. Using FI34, we found elevated levels of resting metabolic rate linked to declining health in nonagenarians. Using FI34 as a quantitative phenotype, we have also found a genomic region on chromosome 12 that is associated with healthy aging and longevity. PMID:26005669

  6. Quantitative mass spectrometry of unconventional human biological matrices

    Science.gov (United States)

    Dutkiewicz, Ewelina P.; Urban, Pawel L.

    2016-10-01

    The development of sensitive and versatile mass spectrometric methodology has fuelled interest in the analysis of metabolites and drugs in unconventional biological specimens. Here, we discuss the analysis of eight human matrices-hair, nail, breath, saliva, tears, meibum, nasal mucus and skin excretions (including sweat)-by mass spectrometry (MS). The use of such specimens brings a number of advantages, the most important being non-invasive sampling, the limited risk of adulteration and the ability to obtain information that complements blood and urine tests. The most often studied matrices are hair, breath and saliva. This review primarily focuses on endogenous (e.g. potential biomarkers, hormones) and exogenous (e.g. drugs, environmental contaminants) small molecules. The majority of analytical methods used chromatographic separation prior to MS; however, such a hyphenated methodology greatly limits analytical throughput. On the other hand, the mass spectrometric methods that exclude chromatographic separation are fast but suffer from matrix interferences. To enable development of quantitative assays for unconventional matrices, it is desirable to standardize the protocols for the analysis of each specimen and create appropriate certified reference materials. Overcoming these challenges will make analysis of unconventional human biological matrices more common in a clinical setting. This article is part of the themed issue 'Quantitative mass spectrometry'.

  7. Quantitative analysis of biological fluids by electron probe and X ray spectrometry

    International Nuclear Information System (INIS)

    Girod, Chantal

    1986-01-01

    In order to know the kidney normal operation and to have an insight on cellular transport mechanisms and hormonal regulations at the nephron level, a technique based on the use of an electron probe has been developed for the elemental analysis of micro-volumes of biological fluids. This academic document reports applications of this technique on animals on which such fluids have been sampled at different levels of the nephron. As these samples are available in too small volumes to be dosed by conventional methods, they have been quantitatively analysed by using an electronic probe based analyser in order to determine concentrations of all elements with an atomic number greater than that of carbon. After a presentation of the implemented method and hardware, the author thus describes how an analysis is performed, and reports and discusses an example (analysis conditions, data acquisition, data processing, minimum detectable concentration, reasons for measurement scattering)

  8. Quantitative characterization of nanoparticle agglomeration within biological media

    International Nuclear Information System (INIS)

    Hondow, Nicole; Brydson, Rik; Wang, Peiyi; Holton, Mark D.; Brown, M. Rowan; Rees, Paul; Summers, Huw D.; Brown, Andy

    2012-01-01

    Quantitative analysis of nanoparticle dispersion state within biological media is essential to understanding cellular uptake and the roles of diffusion, sedimentation, and endocytosis in determining nanoparticle dose. The dispersion of polymer-coated CdTe/ZnS quantum dots in water and cell growth medium with and without fetal bovine serum was analyzed by transmission electron microscopy (TEM) and dynamic light scattering (DLS) techniques. Characterization by TEM of samples prepared by plunge freezing the blotted solutions into liquid ethane was sensitive to the dispersion state of the quantum dots and enabled measurement of agglomerate size distributions even in the presence of serum proteins where DLS failed. In addition, TEM showed a reduced packing fraction of quantum dots per agglomerate when dispersed in biological media and serum compared to just water, highlighting the effect of interactions between the media, serum proteins, and the quantum dots. The identification of a heterogeneous distribution of quantum dots and quantum dot agglomerates in cell growth medium and serum by TEM will enable correlation with the previously reported optical metrology of in vitro cellular uptake of this quantum dot dispersion. In this paper, we present a comparative study of TEM and DLS and show that plunge-freeze TEM provides a robust assessment of nanoparticle agglomeration state.

  9. Development of a Biological Science Quantitative Reasoning Exam (BioSQuaRE)

    Science.gov (United States)

    Stanhope, Liz; Ziegler, Laura; Haque, Tabassum; Le, Laura; Vinces, Marcelo; Davis, Gregory K.; Zieffler, Andrew; Brodfuehrer, Peter; Preest, Marion; Belitsky, Jason M.; Umbanhowar, Charles, Jr.; Overvoorde, Paul J.

    2017-01-01

    Multiple reports highlight the increasingly quantitative nature of biological research and the need to innovate means to ensure that students acquire quantitative skills. We present a tool to support such innovation. The Biological Science Quantitative Reasoning Exam (BioSQuaRE) is an assessment instrument designed to measure the quantitative…

  10. Biological Dynamics Markup Language (BDML): an open format for representing quantitative biological dynamics data.

    Science.gov (United States)

    Kyoda, Koji; Tohsato, Yukako; Ho, Kenneth H L; Onami, Shuichi

    2015-04-01

    Recent progress in live-cell imaging and modeling techniques has resulted in generation of a large amount of quantitative data (from experimental measurements and computer simulations) on spatiotemporal dynamics of biological objects such as molecules, cells and organisms. Although many research groups have independently dedicated their efforts to developing software tools for visualizing and analyzing these data, these tools are often not compatible with each other because of different data formats. We developed an open unified format, Biological Dynamics Markup Language (BDML; current version: 0.2), which provides a basic framework for representing quantitative biological dynamics data for objects ranging from molecules to cells to organisms. BDML is based on Extensible Markup Language (XML). Its advantages are machine and human readability and extensibility. BDML will improve the efficiency of development and evaluation of software tools for data visualization and analysis. A specification and a schema file for BDML are freely available online at http://ssbd.qbic.riken.jp/bdml/. Supplementary data are available at Bioinformatics online. © The Author 2014. Published by Oxford University Press.

  11. Biological evolution of replicator systems: towards a quantitative approach.

    Science.gov (United States)

    Martin, Osmel; Horvath, J E

    2013-04-01

    The aim of this work is to study the features of a simple replicator chemical model of the relation between kinetic stability and entropy production under the action of external perturbations. We quantitatively explore the different paths leading to evolution in a toy model where two independent replicators compete for the same substrate. To do that, the same scenario described originally by Pross (J Phys Org Chem 17:312-316, 2004) is revised and new criteria to define the kinetic stability are proposed. Our results suggest that fast replicator populations are continually favored by the effects of strong stochastic environmental fluctuations capable to determine the global population, the former assumed to be the only acting evolution force. We demonstrate that the process is continually driven by strong perturbations only, and that population crashes may be useful proxies for these catastrophic environmental fluctuations. As expected, such behavior is particularly enhanced under very large scale perturbations, suggesting a likely dynamical footprint in the recovery patterns of new species after mass extinction events in the Earth's geological past. Furthermore, the hypothesis that natural selection always favors the faster processes may give theoretical support to different studies that claim the applicability of maximum principles like the Maximum Metabolic Flux (MMF) or Maximum Entropy Productions Principle (MEPP), seen as the main goal of biological evolution.

  12. Review of progress in quantitative nondestructive evaluation. Volume 8A and Volume 8B

    International Nuclear Information System (INIS)

    Thompson, D.O.; Chimenti, D.E.

    1989-01-01

    Volume 8 contains the edited papers presented at the 1988 Review of Progress in Quantitative Nondestructive Evaluation meeting. The 288 papers discuss such topics as fundamental techniques as acoustic testing, eddy current testing, and x-ray radiography; advanced techniques using x-ray computed tomography and laser ultrasonics; interpretive signal and image processing using expert systems and adaptive analysis; NDE probes and sensors and NDE systems and instrumentation; materials process control and inspection reliability including human factors. Materials discussed range from electronic circuit materials, coatings, adhesive bonds, smart structures, composite materials, welded joints, ferrous materials, and steels and alloys. Stress, texture, structural and fracture properties of materials are characterized using various NDE techniques. Applications to reactor, aircraft, and space vehicle components are investigated

  13. Biological modelling of fuzzy target volumes in 3D radiotherapy

    International Nuclear Information System (INIS)

    Levegruen, S.; Kampen, M. van; Waschek, T.; Engenhart, R.; Schlegel, W.

    1995-01-01

    increase in NTCP is then calculated for a homogeneous dose distribution extending the boundaries of the volume considered towards the maximal PTV. Results: The behavior of the model and its dependence on the input parameters was investigated for the case of a brain tumor. Going from the minimal PTV towards the maximal PTV, the TCP increases show a sigmoidal shape. The increase in NTCP depends for each patient on the relative position of the organs at risk with respect to the region of uncertainty. We use the model as input into a computer assisted expert system based on Fuzzy Logic. Output of the Fuzzy system is the target volume which, for each individual patient, leads to the best compromise between high tumor control probability on one side and a low risk of complications on the other side. With this system the extent of the target volume towards noncritical structures is large, whereas the boundaries near an organ at risk within the region of uncertainty are strongly influenced by the partial volume of that organ at risk irradiated. Conclusion: At present biological models, in particular of TCP, suffer from a lack of data for the biological input parameters, especially for the density and distribution of clonogenic cells. The better these input parameters become established in the future, the more the model described here will serve as an important aid for the radiotherapist in the definition of the optimal target volume

  14. Progress in quantitative X-ray microanalysis of frozen-hydrated bulk biological samples

    International Nuclear Information System (INIS)

    Marshall, A.T.

    1988-01-01

    The analysis of bulk frozen-hydrated biological samples has developed now to a level where practical application of the technique is possible. Provided the sample is carefully coated with a conductive metal, the development of a space charge capable of causing a significant distortion of the electron diffusion volume does not seem to occur, and analytical resolution can be conveniently held to approximately 2 micron (both depth and lateral resolution). Two valid quantitative methods are available, and two methods of determining dry weight fractions are also available. An area where further research could lead to improvement in analysis of frozen-hydrated bulk samples is in the investigation of fracturing methods. If fracture planes that were flat and reproducible could be easily obtained, some of the difficulties of analysing frozen-hydrated bulk samples would be considerably reduced

  15. Low cost biological lung volume reduction therapy for advanced emphysema

    Directory of Open Access Journals (Sweden)

    Bakeer M

    2016-08-01

    Full Text Available Mostafa Bakeer,1 Taha Taha Abdelgawad,1 Raed El-Metwaly,1 Ahmed El-Morsi,1 Mohammad Khairy El-Badrawy,1 Solafa El-Sharawy2 1Chest Medicine Department, 2Clinical Pathology Department, Faculty of Medicine, Mansoura University, Mansoura, Egypt Background: Bronchoscopic lung volume reduction (BLVR, using biological agents, is one of the new alternatives to lung volume reduction surgery.Objectives: To evaluate efficacy and safety of biological BLVR using low cost agents including autologous blood and fibrin glue.Methods: Enrolled patients were divided into two groups: group A (seven patients in which autologous blood was used and group B (eight patients in which fibrin glue was used. The agents were injected through a triple lumen balloon catheter via fiberoptic bronchoscope. Changes in high resolution computerized tomography (HRCT volumetry, pulmonary function tests, symptoms, and exercise capacity were evaluated at 12 weeks postprocedure as well as for complications.Results: In group A, at 12 weeks postprocedure, there was significant improvement in the mean value of HRCT volumetry and residual volume/total lung capacity (% predicted (P-value: <0.001 and 0.038, respectively. In group B, there was significant improvement in the mean value of HRCT volumetry and (residual volume/total lung capacity % predicted (P-value: 0.005 and 0.004, respectively. All patients tolerated the procedure with no mortality.Conclusion: BLVR using autologous blood and locally prepared fibrin glue is a promising method for therapy of advanced emphysema in term of efficacy, safety as well as cost effectiveness. Keywords: BLVR, bronchoscopy, COPD, interventional pulmonology

  16. Automatic definition of targeted biological volumes for the radiotherapy applications

    International Nuclear Information System (INIS)

    Hatt, M.; Visvikis, D.; Cheze-Le-Rest, C.; Pradier, O.

    2009-01-01

    The proposed method: Fuzzy locally adaptive Bayesian (F.L.A.B.) showed its reliability and its precision on very complete collection of realistic simulated and real data. Its use in the context of radiotherapy allows to consider easily the studies implementation and scenari of dose painting or dose escalation, including in complex cases of heterogenous fixations. It is conceivable to apply F.L.A.B. on PET images with F.M.I.S.O. ( 18 F fluoro misonidazole) or F.L.T. (fluoro-L-thymidine) to complete the definition of the biological target volume. (N.C.)

  17. Quantitative CT: technique dependence of volume estimation on pulmonary nodules

    Science.gov (United States)

    Chen, Baiyu; Barnhart, Huiman; Richard, Samuel; Colsher, James; Amurao, Maxwell; Samei, Ehsan

    2012-03-01

    Current estimation of lung nodule size typically relies on uni- or bi-dimensional techniques. While new three-dimensional volume estimation techniques using MDCT have improved size estimation of nodules with irregular shapes, the effect of acquisition and reconstruction parameters on accuracy (bias) and precision (variance) of the new techniques has not been fully investigated. To characterize the volume estimation performance dependence on these parameters, an anthropomorphic chest phantom containing synthetic nodules was scanned and reconstructed with protocols across various acquisition and reconstruction parameters. Nodule volumes were estimated by a clinical lung analysis software package, LungVCAR. Precision and accuracy of the volume assessment were calculated across the nodules and compared between protocols via a generalized estimating equation analysis. Results showed that the precision and accuracy of nodule volume quantifications were dependent on slice thickness, with different dependences for different nodule characteristics. Other parameters including kVp, pitch, and reconstruction kernel had lower impact. Determining these technique dependences enables better volume quantification via protocol optimization and highlights the importance of consistent imaging parameters in sequential examinations.

  18. Quantitative analysis of normal fetal brain volume and flow by three-dimensional power Doppler ultrasound

    Directory of Open Access Journals (Sweden)

    Ju-Chun Hsu

    2013-09-01

    Conclusion: 3D ultrasound can be used to assess the fetal brain volume and blood flow development quantitatively. Our study indicates that the fetal brain vascularization and blood flow correlates significantly with the advancement of GA. This information may serve as a reference point for further studies of the fetal brain volume and blood flow in abnormal conditions.

  19. Laser-induced incandescence: Towards quantitative soot volume fraction measurements

    Energy Technology Data Exchange (ETDEWEB)

    Tzannis, A P; Wienbeucker, F; Beaud, P; Frey, H -M; Gerber, T; Mischler, B; Radi, P P [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1999-08-01

    Laser-Induced Incandescence has recently emerged as a versatile tool for measuring soot volume fraction in a wide range of combustion systems. In this work we investigate the essential features of the method. LII is based on the acquisition of the incandescence of soot when heated through a high power laser pulse. Initial experiments have been performed on a model laboratory flame. The behaviour of the LII signal is studied experimentally. By applying numerical calculations we investigate the possibility to obtain two-dimensional soot volume fraction distributions. For this purpose a combination of LII with other techniques is required. This part is discussed in some extent and the future work is outlined. (author) 4 figs., 3 refs.

  20. Amines as extracting agents for the quantitative determinations of actinides in biological samples

    International Nuclear Information System (INIS)

    Singh, N.P.

    1987-01-01

    The use of amines (primary, secondary and tertiary chains and quaternary ammonium salts) as extracting agents for the quantitative determination of actinides in biological samples is reviewed. Among the primary amines, only Primene JM-T is used to determine Pu in urine and bone. No one has investigated the possibility of using secondary amines to quantitatively extract actinides from biological samples. Among the tertiary amines, tri-n-octylamine, tri-iso-octylamine, tyricaprylamine (Alamine) and trilaurylamine (tridodecylamine) are used extensively to extract and separate the actinides from biological samples. Only one quaternary ammonium salt, methyltricapryl ammonium chloride (Aliquat-336), is used to extract Pu from biological samples. (author) 28 refs

  1. Space Biology and Medicine. Volume I; Space and Its Exploration

    Science.gov (United States)

    Nicogossian, Arnauld E.; Mohler, Stanley R.; Gazenko, Oleg G.; Grigoryev, Anatoliy I.

    1993-01-01

    and a path to our common future. But for humanity to embark on this path, we need to understand ourselves in a new environment. As such, an understanding of the biological consequences of and opportunities in space flight is essential. In this, the first volume of a joint U.S./Russian series on space biology and medicine, we describe the current status of our understanding of space and present general information that will prove useful when reading subsequent volumes. Since we are witnesses to the beginning of a new era of interplanetary travel, a significant portion of the first volume will concentrate on the physical and ecological conditions that exist in near and outer space, as well as heavenly bodies from the smallest ones to the giant planets and stars. While space exploration is a comparatively recent endeavor, its foundations were laid much more than 30 years ago, and its history has been an eventful one. In the first part of this volume, Rauschenbach, Sokolskiy, and Gurjian address the "Historical Aspects of Space Exploration" from its beginnings to a present-day view of the events of the space age. The nature of space itself and its features is the focus of the second section of the volume. In the first chapter of the part, "Stars and Interstellar Space," the origin and evolution of stars, and the nature of the portions of space most distant from Earth are described by Galeev and Marochnik. In Chapter 2, Pisarenko, Logachev, and Kurt in "The Sun and Interplanetary Space" bring us to the vicinity of our own solar system and provide a description and discussion of the nearest star and its influence on the space environment that our Earth and the other planets inhabit. In our solar system there are many fascinating objects, remnants of the formation of a rather ordinary star in a rather obscure portion of the galaxy. Historical accident has caused us to be much more curious (and knowledgeable) about "The Inner Planets of the Solar System" than about any of

  2. Understanding the heterogeneity in volume overload and fluid distribution in decompensated heart failure is key to optimal volume management: role for blood volume quantitation.

    Science.gov (United States)

    Miller, Wayne L; Mullan, Brian P

    2014-06-01

    This study sought to quantitate total blood volume (TBV) in patients hospitalized for decompensated chronic heart failure (DCHF) and to determine the extent of volume overload, and the magnitude and distribution of blood volume and body water changes following diuretic therapy. The accurate assessment and management of volume overload in patients with DCHF remains problematic. TBV was measured by a radiolabeled-albumin dilution technique with intravascular volume, pre-to-post-diuretic therapy, evaluated at hospital admission and at discharge. Change in body weight in relation to quantitated TBV was used to determine interstitial volume contribution to total fluid loss. Twenty-six patients were prospectively evaluated. Two patients had normal TBV at admission. Twenty-four patients were hypervolemic with TBV (7.4 ± 1.6 liters) increased by +39 ± 22% (range, +9.5% to +107%) above the expected normal volume. With diuresis, TBV decreased marginally (+30 ± 16%). Body weight declined by 6.9 ± 5.2 kg, and fluid intake/fluid output was a net negative 8.4 ± 5.2 liters. Interstitial compartment fluid loss was calculated at 6.2 ± 4.0 liters, accounting for 85 ± 15% of the total fluid reduction. TBV analysis demonstrated a wide range in the extent of intravascular overload. Dismissal measurements revealed marginally reduced intravascular volume post-diuretic therapy despite large reductions in body weight. Mobilization of interstitial fluid to the intravascular compartment with diuresis accounted for this disparity. Intravascular volume, however, remained increased at dismissal. The extent, composition, and distribution of volume overload are highly variable in DCHF, and this variability needs to be taken into account in the approach to individualized therapy. TBV quantitation, particularly serial measurements, can facilitate informed volume management with respect to a goal of treating to euvolemia. Copyright © 2014 American College of Cardiology Foundation. Published

  3. Quantitative imaging of single upconversion nanoparticles in biological tissue.

    Directory of Open Access Journals (Sweden)

    Annemarie Nadort

    Full Text Available The unique luminescent properties of new-generation synthetic nanomaterials, upconversion nanoparticles (UCNPs, enabled high-contrast optical biomedical imaging by suppressing the crowded background of biological tissue autofluorescence and evading high tissue absorption. This raised high expectations on the UCNP utilities for intracellular and deep tissue imaging, such as whole animal imaging. At the same time, the critical nonlinear dependence of the UCNP luminescence on the excitation intensity results in dramatic signal reduction at (∼1 cm depth in biological tissue. Here, we report on the experimental and theoretical investigation of this trade-off aiming at the identification of optimal application niches of UCNPs e.g. biological liquids and subsurface tissue layers. As an example of such applications, we report on single UCNP imaging through a layer of hemolyzed blood. To extend this result towards in vivo applications, we quantified the optical properties of single UCNPs and theoretically analyzed the prospects of single-particle detectability in live scattering and absorbing bio-tissue using a human skin model. The model predicts that a single 70-nm UCNP would be detectable at skin depths up to 400 µm, unlike a hardly detectable single fluorescent (fluorescein dye molecule. UCNP-assisted imaging in the ballistic regime thus allows for excellent applications niches, where high sensitivity is the key requirement.

  4. Bremsstrahlung background and quantitation of thin biological samples

    International Nuclear Information System (INIS)

    Khan, K.M.

    1991-02-01

    An inherent feature of all electron-excited X-ray spectra is the presence of a background upon which the characteristic peaks of interest are superimposed. To extract the x-ray intensity of the characteristics lines of interest, it is necessary to subtract this background, which may be due to both specimen generated Bremsstrahlung and extraneous sources, from a measured x-ray spectrum. Some conventional methods of background subtraction will be briefly reviewed. It has been seen that these conventional methods do not give sufficiently accurate results in biological analysis where the peaks of interest are not well-separated and most of the peaks lie in the region where the background is appreciably curved. An alternative approach of background subtraction for such samples is investigated which involves modelling the background using the currently available knowledge of x-ray physics and energy dispersive detectors. This method is particularly suitable for biological samples as well as other samples having an organic matrix. 6 figs. (author)

  5. On the analysis of complex biological supply chains: From Process Systems Engineering to Quantitative Systems Pharmacology.

    Science.gov (United States)

    Rao, Rohit T; Scherholz, Megerle L; Hartmanshenn, Clara; Bae, Seul-A; Androulakis, Ioannis P

    2017-12-05

    The use of models in biology has become particularly relevant as it enables investigators to develop a mechanistic framework for understanding the operating principles of living systems as well as in quantitatively predicting their response to both pathological perturbations and pharmacological interventions. This application has resulted in a synergistic convergence of systems biology and pharmacokinetic-pharmacodynamic modeling techniques that has led to the emergence of quantitative systems pharmacology (QSP). In this review, we discuss how the foundational principles of chemical process systems engineering inform the progressive development of more physiologically-based systems biology models.

  6. Quantitative analysis of dynamic association in live biological fluorescent samples.

    Directory of Open Access Journals (Sweden)

    Pekka Ruusuvuori

    Full Text Available Determining vesicle localization and association in live microscopy may be challenging due to non-simultaneous imaging of rapidly moving objects with two excitation channels. Besides errors due to movement of objects, imaging may also introduce shifting between the image channels, and traditional colocalization methods cannot handle such situations. Our approach to quantifying the association between tagged proteins is to use an object-based method where the exact match of object locations is not assumed. Point-pattern matching provides a measure of correspondence between two point-sets under various changes between the sets. Thus, it can be used for robust quantitative analysis of vesicle association between image channels. Results for a large set of synthetic images shows that the novel association method based on point-pattern matching demonstrates robust capability to detect association of closely located vesicles in live cell-microscopy where traditional colocalization methods fail to produce results. In addition, the method outperforms compared Iterated Closest Points registration method. Results for fixed and live experimental data shows the association method to perform comparably to traditional methods in colocalization studies for fixed cells and to perform favorably in association studies for live cells.

  7. Using Active Learning to Teach Concepts and Methods in Quantitative Biology.

    Science.gov (United States)

    Waldrop, Lindsay D; Adolph, Stephen C; Diniz Behn, Cecilia G; Braley, Emily; Drew, Joshua A; Full, Robert J; Gross, Louis J; Jungck, John A; Kohler, Brynja; Prairie, Jennifer C; Shtylla, Blerta; Miller, Laura A

    2015-11-01

    This article provides a summary of the ideas discussed at the 2015 Annual Meeting of the Society for Integrative and Comparative Biology society-wide symposium on Leading Students and Faculty to Quantitative Biology through Active Learning. It also includes a brief review of the recent advancements in incorporating active learning approaches into quantitative biology classrooms. We begin with an overview of recent literature that shows that active learning can improve students' outcomes in Science, Technology, Engineering and Math Education disciplines. We then discuss how this approach can be particularly useful when teaching topics in quantitative biology. Next, we describe some of the recent initiatives to develop hands-on activities in quantitative biology at both the graduate and the undergraduate levels. Throughout the article we provide resources for educators who wish to integrate active learning and technology into their classrooms. © The Author 2015. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

  8. Quantitative prediction of respiratory tidal volume based on the external torso volume change: a potential volumetric surrogate

    International Nuclear Information System (INIS)

    Li Guang; Arora, Naveen C; Xie Huchen; Ning, Holly; Citrin, Deborah; Kaushal, Aradhana; Zach, Leor; Camphausen, Kevin; Miller, Robert W; Lu Wei; Low, Daniel

    2009-01-01

    An external respiratory surrogate that not only highly correlates with but also quantitatively predicts internal tidal volume should be useful in guiding four-dimensional computed tomography (4DCT), as well as 4D radiation therapy (4DRT). A volumetric surrogate should have advantages over external fiducial point(s) for monitoring respiration-induced motion of the torso, which deforms in synchronization with a patient-specific breathing pattern. This study establishes a linear relationship between the external torso volume change (TVC) and lung air volume change (AVC) by validating a proposed volume conservation hypothesis (TVC = AVC) throughout the respiratory cycle using 4DCT and spirometry. Fourteen patients' torso 4DCT images and corresponding spirometric tidal volumes were acquired to examine this hypothesis. The 4DCT images were acquired using dual surrogates in cine mode and amplitude-based binning in 12 respiratory stages, minimizing residual motion artifacts. Torso and lung volumes were calculated using threshold-based segmentation algorithms and volume changes were calculated relative to the full-exhalation stage. The TVC and AVC, as functions of respiratory stages, were compared, showing a high correlation (r = 0.992 ± 0.005, p 2 = 0.980) without phase shift. The AVC was also compared to the spirometric tidal volumes, showing a similar linearity (slope = 1.030 ± 0.092, R 2 = 0.947). In contrast, the thoracic and abdominal heights measured from 4DCT showed relatively low correlation (0.28 ± 0.44 and 0.82 ± 0.30, respectively) and location-dependent phase shifts. This novel approach establishes the foundation for developing an external volumetric respiratory surrogate.

  9. Quantitative prediction of respiratory tidal volume based on the external torso volume change: a potential volumetric surrogate

    Energy Technology Data Exchange (ETDEWEB)

    Li Guang; Arora, Naveen C; Xie Huchen; Ning, Holly; Citrin, Deborah; Kaushal, Aradhana; Zach, Leor; Camphausen, Kevin; Miller, Robert W [Radiation Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States); Lu Wei; Low, Daniel [Department of Radiation Oncology, Washington University School of Medicine, St Louis, MO 63110 (United States)], E-mail: ligeorge@mail.nih.gov

    2009-04-07

    An external respiratory surrogate that not only highly correlates with but also quantitatively predicts internal tidal volume should be useful in guiding four-dimensional computed tomography (4DCT), as well as 4D radiation therapy (4DRT). A volumetric surrogate should have advantages over external fiducial point(s) for monitoring respiration-induced motion of the torso, which deforms in synchronization with a patient-specific breathing pattern. This study establishes a linear relationship between the external torso volume change (TVC) and lung air volume change (AVC) by validating a proposed volume conservation hypothesis (TVC = AVC) throughout the respiratory cycle using 4DCT and spirometry. Fourteen patients' torso 4DCT images and corresponding spirometric tidal volumes were acquired to examine this hypothesis. The 4DCT images were acquired using dual surrogates in cine mode and amplitude-based binning in 12 respiratory stages, minimizing residual motion artifacts. Torso and lung volumes were calculated using threshold-based segmentation algorithms and volume changes were calculated relative to the full-exhalation stage. The TVC and AVC, as functions of respiratory stages, were compared, showing a high correlation (r = 0.992 {+-} 0.005, p < 0.0001) as well as a linear relationship (slope = 1.027 {+-} 0.061, R{sup 2} = 0.980) without phase shift. The AVC was also compared to the spirometric tidal volumes, showing a similar linearity (slope = 1.030 {+-} 0.092, R{sup 2} = 0.947). In contrast, the thoracic and abdominal heights measured from 4DCT showed relatively low correlation (0.28 {+-} 0.44 and 0.82 {+-} 0.30, respectively) and location-dependent phase shifts. This novel approach establishes the foundation for developing an external volumetric respiratory surrogate.

  10. Isobio software: biological dose distribution and biological dose volume histogram from physical dose conversion using linear-quadratic-linear model.

    Science.gov (United States)

    Jaikuna, Tanwiwat; Khadsiri, Phatchareewan; Chawapun, Nisa; Saekho, Suwit; Tharavichitkul, Ekkasit

    2017-02-01

    To develop an in-house software program that is able to calculate and generate the biological dose distribution and biological dose volume histogram by physical dose conversion using the linear-quadratic-linear (LQL) model. The Isobio software was developed using MATLAB version 2014b to calculate and generate the biological dose distribution and biological dose volume histograms. The physical dose from each voxel in treatment planning was extracted through Computational Environment for Radiotherapy Research (CERR), and the accuracy was verified by the differentiation between the dose volume histogram from CERR and the treatment planning system. An equivalent dose in 2 Gy fraction (EQD 2 ) was calculated using biological effective dose (BED) based on the LQL model. The software calculation and the manual calculation were compared for EQD 2 verification with pair t -test statistical analysis using IBM SPSS Statistics version 22 (64-bit). Two and three-dimensional biological dose distribution and biological dose volume histogram were displayed correctly by the Isobio software. Different physical doses were found between CERR and treatment planning system (TPS) in Oncentra, with 3.33% in high-risk clinical target volume (HR-CTV) determined by D 90% , 0.56% in the bladder, 1.74% in the rectum when determined by D 2cc , and less than 1% in Pinnacle. The difference in the EQD 2 between the software calculation and the manual calculation was not significantly different with 0.00% at p -values 0.820, 0.095, and 0.593 for external beam radiation therapy (EBRT) and 0.240, 0.320, and 0.849 for brachytherapy (BT) in HR-CTV, bladder, and rectum, respectively. The Isobio software is a feasible tool to generate the biological dose distribution and biological dose volume histogram for treatment plan evaluation in both EBRT and BT.

  11. Development and Assessment of Modules to Integrate Quantitative Skills in Introductory Biology Courses.

    Science.gov (United States)

    Hoffman, Kathleen; Leupen, Sarah; Dowell, Kathy; Kephart, Kerrie; Leips, Jeff

    2016-01-01

    Redesigning undergraduate biology courses to integrate quantitative reasoning and skill development is critical to prepare students for careers in modern medicine and scientific research. In this paper, we report on the development, implementation, and assessment of stand-alone modules that integrate quantitative reasoning into introductory biology courses. Modules are designed to improve skills in quantitative numeracy, interpreting data sets using visual tools, and making inferences about biological phenomena using mathematical/statistical models. We also examine demographic/background data that predict student improvement in these skills through exposure to these modules. We carried out pre/postassessment tests across four semesters and used student interviews in one semester to examine how students at different levels approached quantitative problems. We found that students improved in all skills in most semesters, although there was variation in the degree of improvement among skills from semester to semester. One demographic variable, transfer status, stood out as a major predictor of the degree to which students improved (transfer students achieved much lower gains every semester, despite the fact that pretest scores in each focus area were similar between transfer and nontransfer students). We propose that increased exposure to quantitative skill development in biology courses is effective at building competency in quantitative reasoning. © 2016 K. Hoffman, S. Leupen, et al. CBE—Life Sciences Education © 2016 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  12. Biphasic dose responses in biology, toxicology and medicine: Accounting for their generalizability and quantitative features

    International Nuclear Information System (INIS)

    Calabrese, Edward J.

    2013-01-01

    The most common quantitative feature of the hormetic-biphasic dose response is its modest stimulatory response which at maximum is only 30–60% greater than control values, an observation that is consistently independent of biological model, level of organization (i.e., cell, organ or individual), endpoint measured, chemical/physical agent studied, or mechanism. This quantitative feature suggests an underlying “upstream” mechanism common across biological systems, therefore basic and general. Hormetic dose response relationships represent an estimate of the peak performance of integrative biological processes that are allometrically based. Hormetic responses reflect both direct stimulatory or overcompensation responses to damage induced by relatively low doses of chemical or physical agents. The integration of the hormetic dose response within an allometric framework provides, for the first time, an explanation for both the generality and the quantitative features of the hormetic dose response. -- Highlights: •The hormetic stimulation is at maximum 30–60% greater than control responses. •Hormesis is a measure of biological performance and plasticity. •The hormetic response is evolutionary based and highly generalizable. -- This paper provides a biologically based explanation for the generalizability/quantitative features of the hormetic dose response, representing a fundamental contribution to the field

  13. Prospects and challenges of quantitative phase imaging in tumor cell biology

    Science.gov (United States)

    Kemper, Björn; Götte, Martin; Greve, Burkhard; Ketelhut, Steffi

    2016-03-01

    Quantitative phase imaging (QPI) techniques provide high resolution label-free quantitative live cell imaging. Here, prospects and challenges of QPI in tumor cell biology are presented, using the example of digital holographic microscopy (DHM). It is shown that the evaluation of quantitative DHM phase images allows the retrieval of different parameter sets for quantification of cellular motion changes in migration and motility assays that are caused by genetic modifications. Furthermore, we demonstrate simultaneously label-free imaging of cell growth and morphology properties.

  14. Quantitation of right and left ventricular volume with MR imaging in patients with primary pulmonary hypertension

    International Nuclear Information System (INIS)

    Boxt, L.M.; Katz, J.; Kolb, T.; Czegledy, F.P.; Barst, R.J.

    1990-01-01

    This paper tests the utility of MR imaging in quantitating changes in ventricular volume and function in patients with primary pulmonary hypertension (PPH). Right ventricular (RV) and left ventricular (LV) end-diastolic (ED) and end-systolic (ES) volumes were determined in six patients with PPH and in eight controls. Short-axis images were obtained from the cardiac apex to the base at ED and ES, and the ventricular cavities were planimetered. Volumes were computed by summing the areas of the cavities times the thickness of the sections (12-14 mm). The intersection gap (1-3 mm) was averaged between adjacent sections. Results were indexed to the subject's body surface area. This technique was verified by comparison of results obtained by this method with the water displacement volumes of ventricular casts of eight excised bovine hearts and six water-filled balloons. Linear regression and the unpaired Students t test were used to test significance

  15. CADDIS Volume 4. Data Analysis: Biological and Environmental Data Requirements

    Science.gov (United States)

    Overview of PECBO Module, using scripts to infer environmental conditions from biological observations, statistically estimating species-environment relationships, methods for inferring environmental conditions, statistical scripts in module.

  16. Quantitative study on lung volume and lung perfusion using SPECT and CT in thoracal tumors

    International Nuclear Information System (INIS)

    Beyer-Enke, S.A.; Goerich, J.; Strauss, L.G.

    1988-01-01

    22 patients with space occupying lesions in the thoracal region were investigated by computer tomography and by perfusion scintigraphy using SPECT. In order to evaluate the CT images quantitatively, the lung volume was determined using approximation method and compared with the perfusion in the SPECT study. For this, anatomically equivalent transaxial SPECT slices had been coordinated to the CT slices. Between the determined lung volumes and the activity in the ocrresponding layers, a statistically significant correlation was found. It could be shown that the stronger perfusion, frequently observed at the right side of the healthy lung, may be explained by an higher volume of the right pulmonary lobe. Whereas in benign displacing processes the relation activity to volume was similar to the one of the healthy lung, a strongly reduced perfusion together with inconspicuous lung volumes became apparent with malignant tumors. In addition to the great morphological evidence of CT and SPECT studies, additional informations regarding the dignity of displacing processes may be derived from the quantitative evaluation of both methods. (orig.) [de

  17. Modeling optical behavior of birefringent biological tissues for evaluation of quantitative polarized light microscopy

    NARCIS (Netherlands)

    Turnhout, van M.C.; Kranenbarg, S.; Leeuwen, van J.L.

    2009-01-01

    Quantitative polarized light microscopy (qPLM) is a popular tool for the investigation of birefringent architectures in biological tissues. Collagen, the most abundant protein in mammals, is such a birefringent material. Interpretation of results of qPLM in terms of collagen network architecture and

  18. Quantitative analysis of CT brain images: a statistical model incorporating partial volume and beam hardening effects

    International Nuclear Information System (INIS)

    McLoughlin, R.F.; Ryan, M.V.; Heuston, P.M.; McCoy, C.T.; Masterson, J.B.

    1992-01-01

    The purpose of this study was to construct and evaluate a statistical model for the quantitative analysis of computed tomographic brain images. Data were derived from standard sections in 34 normal studies. A model representing the intercranial pure tissue and partial volume areas, with allowance for beam hardening, was developed. The average percentage error in estimation of areas, derived from phantom tests using the model, was 28.47%. We conclude that our model is not sufficiently accurate to be of clinical use, even though allowance was made for partial volume and beam hardening effects. (author)

  19. A Checklist for Successful Quantitative Live Cell Imaging in Systems Biology

    Science.gov (United States)

    Sung, Myong-Hee

    2013-01-01

    Mathematical modeling of signaling and gene regulatory networks has provided unique insights about systems behaviors for many cell biological problems of medical importance. Quantitative single cell monitoring has a crucial role in advancing systems modeling of molecular networks. However, due to the multidisciplinary techniques that are necessary for adaptation of such systems biology approaches, dissemination to a wide research community has been relatively slow. In this essay, I focus on some technical aspects that are often under-appreciated, yet critical in harnessing live cell imaging methods to achieve single-cell-level understanding and quantitative modeling of molecular networks. The importance of these technical considerations will be elaborated with examples of successes and shortcomings. Future efforts will benefit by avoiding some pitfalls and by utilizing the lessons collectively learned from recent applications of imaging in systems biology. PMID:24709701

  20. Optimization of quantitative waste volume determination technique for hanford waste tank closure

    International Nuclear Information System (INIS)

    Monts, David L.; Jang, Ping-Rey; Long, Zhiling; Okhuysen, Walter P.; Norton, Olin P.; Gresham, Lawrence L.; Su, Yi; Lindner, Jeffrey S.

    2011-01-01

    The Hanford Site is currently in the process of an extensive effort to empty and close its radioactive single-shell and double-shell waste storage tanks. Before this can be accomplished, it is necessary to know how much residual material is left in a given waste tank and the uncertainty with which that volume is known. The Institute for Clean Energy Technology (ICET) at Mississippi State University is currently developing a quantitative in-tank imaging system based on Fourier Transform Profilometry, FTP. FTP is a non-contact, 3-D shape measurement technique. By projecting a fringe pattern onto a target surface and observing its deformation due to surface irregularities from a different view angle, FTP is capable of determining the height (depth) distribution (and hence volume distribution) of the target surface, thus reproducing the profile of the target accurately under a wide variety of conditions. Hence FTP has the potential to be utilized for quantitative determination of residual wastes within Hanford waste tanks. In this paper, efforts to characterize the accuracy and precision of quantitative volume determination using FTP and the use of these results to optimize the FTP system for deployment within Hanford waste tanks are described. (author)

  1. Quantitative assessment of biological impact using transcriptomic data and mechanistic network models

    International Nuclear Information System (INIS)

    Thomson, Ty M.; Sewer, Alain; Martin, Florian; Belcastro, Vincenzo; Frushour, Brian P.; Gebel, Stephan; Park, Jennifer; Schlage, Walter K.; Talikka, Marja; Vasilyev, Dmitry M.; Westra, Jurjen W.; Hoeng, Julia; Peitsch, Manuel C.

    2013-01-01

    Exposure to biologically active substances such as therapeutic drugs or environmental toxicants can impact biological systems at various levels, affecting individual molecules, signaling pathways, and overall cellular processes. The ability to derive mechanistic insights from the resulting system responses requires the integration of experimental measures with a priori knowledge about the system and the interacting molecules therein. We developed a novel systems biology-based methodology that leverages mechanistic network models and transcriptomic data to quantitatively assess the biological impact of exposures to active substances. Hierarchically organized network models were first constructed to provide a coherent framework for investigating the impact of exposures at the molecular, pathway and process levels. We then validated our methodology using novel and previously published experiments. For both in vitro systems with simple exposure and in vivo systems with complex exposures, our methodology was able to recapitulate known biological responses matching expected or measured phenotypes. In addition, the quantitative results were in agreement with experimental endpoint data for many of the mechanistic effects that were assessed, providing further objective confirmation of the approach. We conclude that our methodology evaluates the biological impact of exposures in an objective, systematic, and quantifiable manner, enabling the computation of a systems-wide and pan-mechanistic biological impact measure for a given active substance or mixture. Our results suggest that various fields of human disease research, from drug development to consumer product testing and environmental impact analysis, could benefit from using this methodology. - Highlights: • The impact of biologically active substances is quantified at multiple levels. • The systems-level impact integrates the perturbations of individual networks. • The networks capture the relationships between

  2. Quantitation of mandibular symphysis volume as a source of bone grafting.

    Science.gov (United States)

    Verdugo, Fernando; Simonian, Krikor; Smith McDonald, Roberto; Nowzari, Hessam

    2010-06-01

    Autogenous intramembranous bone graft present several advantages such as minimal resorption and high concentration of bone morphogenetic proteins. A method for measuring the amount of bone that can be harvested from the symphysis area has not been reported in real patients. The aim of the present study was to intrasurgically quantitate the volume of the symphysis bone graft that can be safely harvested in live patients and compare it with AutoCAD (version 16.0, Autodesk, Inc., San Rafael, CA, USA) tomographic calculations. AutoCAD software program quantitated symphysis bone graft in 40 patients using computerized tomographies. Direct intrasurgical measurements were recorded thereafter and compared with AutoCAD data. The bone volume was measured at the recipient sites of a subgroup of 10 patients, 6 months post sinus augmentation. The volume of bone graft measured by AutoCAD averaged 1.4 mL (SD 0.6 mL, range: 0.5-2.7 mL). The volume of bone graft measured intrasurgically averaged 2.3 mL (SD 0.4 mL, range 1.7-2.8 mL). The statistical difference between the two measurement methods was significant. The bone volume measured at the recipient sites 6 months post sinus augmentation averaged 1.9 mL (SD 0.3 mL, range 1.3-2.6 mL) with a mean loss of 0.4 mL. AutoCAD did not overestimate the volume of bone that can be safely harvested from the mandibular symphysis. The use of the design software program may improve surgical treatment planning prior to sinus augmentation.

  3. Gender, Math Confidence, and Grit: Relationships with Quantitative Skills and Performance in an Undergraduate Biology Course.

    Science.gov (United States)

    Flanagan, K M; Einarson, J

    2017-01-01

    In a world filled with big data, mathematical models, and statistics, the development of strong quantitative skills is becoming increasingly critical for modern biologists. Teachers in this field must understand how students acquire quantitative skills and explore barriers experienced by students when developing these skills. In this study, we examine the interrelationships among gender, grit, and math confidence for student performance on a pre-post quantitative skills assessment and overall performance in an undergraduate biology course. Here, we show that females significantly underperformed relative to males on a quantitative skills assessment at the start of term. However, females showed significantly higher gains over the semester, such that the gender gap in performance was nearly eliminated by the end of the semester. Math confidence plays an important role in the performance on both the pre and post quantitative skills assessments and overall performance in the course. The effect of grit on student performance, however, is mediated by a student's math confidence; as math confidence increases, the positive effect of grit decreases. Consequently, the positive impact of a student's grittiness is observed most strongly for those students with low math confidence. We also found grit to be positively associated with the midterm score and the final grade in the course. Given the relationships established in this study among gender, grit, and math confidence, we provide "instructor actions" from the literature that can be applied in the classroom to promote the development of quantitative skills in light of our findings. © 2017 K. M. Flanagan and J. Einarson. CBE—Life Sciences Education © 2017 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http

  4. Quantitative HPLC determination of [99mTc]-pertechnetate in radiopharmaceuticals and biological samples: Pt. 1

    International Nuclear Information System (INIS)

    Tianze Zhou; Hirth, W.W.; Heineman, W.R.; Deutsch, Edward

    1988-01-01

    Techniques have been developed which allow HPLC (high performance liquid chromatography) to be used for the quantitative determination of [ 99m Tc]pertechnetate in radiopharmaceuticals and biological samples. An instrumental technique accounts for 99m Tc species which do not elute from the HPLC column, while a chemical technique obviates interferences caused by Sn(II). These two techniques are incorporated into an anion exchange HPLC procedure which is applied to the determination of [ 99m Tc]pertechnetate in 99m Tc-diphosphonate radiopharmaceuticals and biological samples. (author)

  5. Doppler sonography of diabetic feet: Quantitative analysis of blood flow volume

    International Nuclear Information System (INIS)

    Seo, Young Lan; Kim, Ho Chul; Choi, Chul Soon; Yoon, Dae Young; Han, Dae Hee; Moon, Jeung Hee; Bae, Sang Hoon

    2002-01-01

    To analyze Doppler sonographic findings of diabetic feet by estimating the quantitative blood flow volume and by analyzing waveform on Doppler. Doppler sonography was performed in thirty four patients (10 diabetic patients with foot ulceration, 14 diabetic patients without ulceration and 10 normal patients as the normal control group) to measure the flow volume of the arteries of the lower extremities (posterior and anterior tibial arteries, and distal femoral artery. Analysis of doppler waveforms was also done to evaluate the nature of the changed blood flow volume of diabetic patients, and the waveforms were classified into triphasic, biphasic-1, biphasic-2 and monophasic patterns. Flow volume of arteries in diabetic patients with foot ulceration was increased witha statistical significance when compared to that of diabetes patients without foot ulceration of that of normal control group (P<0.05). Analysis of Doppler waveform revealed that the frequency of biphasic-2 pattern was significantly higher in diabetic patients than in normal control group(p<0.05). Doppler sonography in diabetic feet showed increased flow volume and biphasic Doppler waveform, and these findings suggest neuropathy rather than ischemic changes in diabetic feet.

  6. A simple, quantitative method using alginate gel to determine rat colonic tumor volume in vivo.

    Science.gov (United States)

    Irving, Amy A; Young, Lindsay B; Pleiman, Jennifer K; Konrath, Michael J; Marzella, Blake; Nonte, Michael; Cacciatore, Justin; Ford, Madeline R; Clipson, Linda; Amos-Landgraf, James M; Dove, William F

    2014-04-01

    Many studies of the response of colonic tumors to therapeutics use tumor multiplicity as the endpoint to determine the effectiveness of the agent. These studies can be greatly enhanced by accurate measurements of tumor volume. Here we present a quantitative method to easily and accurately determine colonic tumor volume. This approach uses a biocompatible alginate to create a negative mold of a tumor-bearing colon; this mold is then used to make positive casts of dental stone that replicate the shape of each original tumor. The weight of the dental stone cast correlates highly with the weight of the dissected tumors. After refinement of the technique, overall error in tumor volume was 16.9% ± 7.9% and includes error from both the alginate and dental stone procedures. Because this technique is limited to molding of tumors in the colon, we utilized the Apc(Pirc/+) rat, which has a propensity for developing colonic tumors that reflect the location of the majority of human intestinal tumors. We have successfully used the described method to determine tumor volumes ranging from 4 to 196 mm³. Alginate molding combined with dental stone casting is a facile method for determining tumor volume in vivo without costly equipment or knowledge of analytic software. This broadly accessible method creates the opportunity to objectively study colonic tumors over time in living animals in conjunction with other experiments and without transferring animals from the facility where they are maintained.

  7. Doppler sonography of diabetic feet: Quantitative analysis of blood flow volume

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Young Lan; Kim, Ho Chul; Choi, Chul Soon; Yoon, Dae Young; Han, Dae Hee; Moon, Jeung Hee; Bae, Sang Hoon [Hallym University College of Medicine, Seoul (Korea, Republic of)

    2002-09-15

    To analyze Doppler sonographic findings of diabetic feet by estimating the quantitative blood flow volume and by analyzing waveform on Doppler. Doppler sonography was performed in thirty four patients (10 diabetic patients with foot ulceration, 14 diabetic patients without ulceration and 10 normal patients as the normal control group) to measure the flow volume of the arteries of the lower extremities (posterior and anterior tibial arteries, and distal femoral artery. Analysis of doppler waveforms was also done to evaluate the nature of the changed blood flow volume of diabetic patients, and the waveforms were classified into triphasic, biphasic-1, biphasic-2 and monophasic patterns. Flow volume of arteries in diabetic patients with foot ulceration was increased witha statistical significance when compared to that of diabetes patients without foot ulceration of that of normal control group (P<0.05). Analysis of Doppler waveform revealed that the frequency of biphasic-2 pattern was significantly higher in diabetic patients than in normal control group(p<0.05). Doppler sonography in diabetic feet showed increased flow volume and biphasic Doppler waveform, and these findings suggest neuropathy rather than ischemic changes in diabetic feet.

  8. Application of LC–MS/MS for quantitative analysis of glucocorticoids and stimulants in biological fluids

    OpenAIRE

    Haneef, Jamshed; Shaharyar, Mohammad; Husain, Asif; Rashid, Mohd; Mishra, Ravinesh; Parveen, Shama; Ahmed, Niyaz; Pal, Manoj; Kumar, Deepak

    2013-01-01

    Liquid chromatography tandem mass chromatography (LCâMS/MS) is an important hyphenated technique for quantitative analysis of drugs in biological fluids. Because of high sensitivity and selectivity, LCâMS/MS has been used for pharmacokinetic studies, metabolites identification in the plasma and urine. This manuscript gives comprehensive analytical review, focusing on chromatographic separation approaches (column packing materials, column length and mobile phase) as well as different acquisiti...

  9. Application of LC–MS/MS for quantitative analysis of glucocorticoids and stimulants in biological fluids

    OpenAIRE

    Haneef, Jamshed; Shaharyar, Mohammad; Husain, Asif; Rashid, Mohd; Mishra, Ravinesh; Parveen, Shama; Ahmed, Niyaz; Pal, Manoj; Kumar, Deepak

    2013-01-01

    Liquid chromatography tandem mass chromatography (LC–MS/MS) is an important hyphenated technique for quantitative analysis of drugs in biological fluids. Because of high sensitivity and selectivity, LC–MS/MS has been used for pharmacokinetic studies, metabolites identification in the plasma and urine. This manuscript gives comprehensive analytical review, focusing on chromatographic separation approaches (column packing materials, column length and mobile phase) as well as different acquisiti...

  10. First experiences with model based iterative reconstructions influence on quantitative plaque volume and intensity measurements in coronary computed tomography angiography

    DEFF Research Database (Denmark)

    Precht, Helle; Kitslaar, Pieter H.; Broersen, Alexander

    2017-01-01

    Purpose: Investigate the influence of adaptive statistical iterative reconstruction (ASIR) and the model- based IR (Veo) reconstruction algorithm in coronary computed tomography angiography (CCTA) im- ages on quantitative measurements in coronary arteries for plaque volumes and intensities. Methods...

  11. Tumor and normal structures volume localization and quantitation in 3D radiotherapy treatment planning

    International Nuclear Information System (INIS)

    Anselmi, R.; Andreucci, L.

    1995-01-01

    Improvements in imaging technology have significantly enhanced the ability of the radiation oncologist to stage and to evaluate the response of tumor during and after treatment. Over the last few year, in fact, computed tomography (CT), magnetic resonance spectroscopy (MRS), positron emission tomography (PET), single photon emission computed tomography (SPECT) imaging radiolabelled monoclonal tumor antibodies have allowed tumor definition and evaluation. Concerning the above mentioned techniques accurate methods for the integration of morphological (CT, MRI) and functional (PET, SPECT, MRS) information can be very useful for volumes definition. In fact three-dimensional treatment planning depends heavily on volume displays and calculation based on volumes to convey information to the radiation oncologist, physicist and dosimetrist. The accuracy and reproducibility of the methods for creating these volumes are fundamental limitations of current treatment planning systems. Slice by slice manual contouring, which is extremely labor-intensive, and automatic edge detection, which has a high failure rate and requires human intervention are representative of the current standard of practice. The aim of our work is both to develop methods of image data integration and automatic segmentation, and to make the treatment planning system able to combine these multiple information in unified data set in order to get a better tumor volume definition and dose distribution calculation. Then the possibility of using morphological and functional images and other information coming from MR spectroscopy and electronic or confocal microscopy can allow the development into the treatment planning system of biological calculation models for evaluating tumor and normal tissue control probabilities (TCP, NTCP). The definitive use of these models into the 3-D treatment plannings will offer a considerable improvement in the biological efficacy of radiotherapy and it will constitute the object

  12. Quantitation of cerebral blood volume by 99mTc-DTPA-HSA SPECT

    International Nuclear Information System (INIS)

    Inoue, Yusuke; Machida, Kikuo; Momose, Toshimitsu

    1992-01-01

    The characteristics of technetium-99m diethylenetriaminepentaacetic acid human serum albumin ( 99m Tc-DTPA-HSA) as an agent for quantitation of cerebral blood volume (CBV) were examined. The radioactivity after decay correction as a percentage of the activity at 10 minutes was 84.3±1.3% at 120 minutes after the injection of 99m Tc-DTPA-HSA. Radioactivity was found exclusively in plasma, with little in blood cells. The blood retention of 99m Tc-DTPA-HSA is sufficient, and its use in the quantitation of CBV omits the need for centrifugation of the blood sample. CBV quantified using the tracer and a SPECT system with a single-head rotating gamma camera was 4.09±0.60 ml/100g brain, similar to values reported previously. Two serial SPECT scans provided similar images, and the CBV values determined by the two scans were closely correlated (p 99m Tc-DTPA-HSA has useful properties for quantitative CBV measurement and that quantitation of CBV by 99m Tc-DTPA-HSA SPECT is feasible using a system with a single-head rotating gamma camera. (author)

  13. Preparation of Biological Samples Containing Metoprolol and Bisoprolol for Applying Methods for Quantitative Analysis

    Directory of Open Access Journals (Sweden)

    Corina Mahu Ştefania

    2015-12-01

    Full Text Available Arterial hypertension is a complex disease with many serious complications, representing a leading cause of mortality. Selective beta-blockers such as metoprolol and bisoprolol are frequently used in the management of hypertension. Numerous analytical methods have been developed for the determination of these substances in biological fluids, such as liquid chromatography coupled with mass spectrometry, gas chromatography coupled with mass spectrometry, high performance liquid chromatography. Due to the complex composition of biological fluids a biological sample pre-treatment before the use of the method for quantitative determination is required in order to remove proteins and potential interferences. The most commonly used methods for processing biological samples containing metoprolol and bisoprolol were identified through a thorough literature search using PubMed, ScienceDirect, and Willey Journals databases. Articles published between years 2005-2015 were reviewed. Protein precipitation, liquid-liquid extraction and solid phase extraction are the main techniques for the extraction of these drugs from plasma, serum, whole blood and urine samples. In addition, numerous other techniques have been developed for the preparation of biological samples, such as dispersive liquid-liquid microextraction, carrier-mediated liquid phase microextraction, hollow fiber-protected liquid phase microextraction, on-line molecularly imprinted solid phase extraction. The analysis of metoprolol and bisoprolol in human plasma, urine and other biological fluids provides important information in clinical and toxicological trials, thus requiring the application of appropriate extraction techniques for the detection of these antihypertensive substances at nanogram and picogram levels.

  14. Introduction to the Symposium "Leading Students and Faculty to Quantitative Biology through Active Learning".

    Science.gov (United States)

    Waldrop, Lindsay D; Miller, Laura A

    2015-11-01

    The broad aim of this symposium and set of associated papers is to motivate the use of inquiry-based, active-learning teaching techniques in undergraduate quantitative biology courses. Practical information, resources, and ready-to-use classroom exercises relevant to physicists, mathematicians, biologists, and engineers are presented. These resources can be used to address the lack of preparation of college students in STEM fields entering the workforce by providing experience working on interdisciplinary and multidisciplinary problems in mathematical biology in a group setting. Such approaches can also indirectly help attract and retain under-represented students who benefit the most from "non-traditional" learning styles and strategies, including inquiry-based, collaborative, and active learning. © The Author 2015. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

  15. Novel gravimetric measurement technique for quantitative volume calibration in the sub-microliter range

    International Nuclear Information System (INIS)

    Liang, Dong; Zengerle, Roland; Steinert, Chris; Ernst, Andreas; Koltay, Peter; Bammesberger, Stefan; Tanguy, Laurent

    2013-01-01

    We present a novel measurement method based on the gravimetric principles adapted from the ASTM E542 and ISO 4787 standards for quantitative volume determination in the sub-microliter range. Such a method is particularly important for the calibration of non-contact micro dispensers as well as other microfluidic devices. The novel method is based on the linear regression analysis of continuously monitored gravimetric results and therefore is referred to as ‘gravimetric regression method (GRM)’. In this context, the regression analysis is necessary to compensate the mass loss due to evaporation that is significant for very small dispensing volumes. A full assessment of the measurement uncertainty of GRM is presented and results in a standard measurement uncertainty around 6 nl for dosage volumes in the range from 40 nl to 1 µl. The GRM has been experimentally benchmarked with a dual-dye ratiometric photometric method (Artel Inc., Westbrook, ME, USA), which can provide traceability of measurement to the International System of Units (SI) through reference standards maintained by NIST. Good precision (max. CV = 2.8%) and consistency (bias around 7 nl in the volume range from 40 to 400 nl) have been observed comparing the two methods. Based on the ASTM and ISO standards on the one hand and the benchmark with the photometric method on the other hand, two different approaches for establishing traceability for the GRM are discussed. (paper)

  16. Physiological frailty index (PFI): quantitative in-life estimate of individual biological age in mice.

    Science.gov (United States)

    Antoch, Marina P; Wrobel, Michelle; Kuropatwinski, Karen K; Gitlin, Ilya; Leonova, Katerina I; Toshkov, Ilia; Gleiberman, Anatoli S; Hutson, Alan D; Chernova, Olga B; Gudkov, Andrei V

    2017-03-19

    The development of healthspan-extending pharmaceuticals requires quantitative estimation of age-related progressive physiological decline. In humans, individual health status can be quantitatively assessed by means of a frailty index (FI), a parameter which reflects the scale of accumulation of age-related deficits. However, adaptation of this methodology to animal models is a challenging task since it includes multiple subjective parameters. Here we report a development of a quantitative non-invasive procedure to estimate biological age of an individual animal by creating physiological frailty index (PFI). We demonstrated the dynamics of PFI increase during chronological aging of male and female NIH Swiss mice. We also demonstrated acceleration of growth of PFI in animals placed on a high fat diet, reflecting aging acceleration by obesity and provide a tool for its quantitative assessment. Additionally, we showed that PFI could reveal anti-aging effect of mTOR inhibitor rapatar (bioavailable formulation of rapamycin) prior to registration of its effects on longevity. PFI revealed substantial sex-related differences in normal chronological aging and in the efficacy of detrimental (high fat diet) or beneficial (rapatar) aging modulatory factors. Together, these data introduce PFI as a reliable, non-invasive, quantitative tool suitable for testing potential anti-aging pharmaceuticals in pre-clinical studies.

  17. Co-clinical quantitative tumor volume imaging in ALK-rearranged NSCLC treated with crizotinib

    Energy Technology Data Exchange (ETDEWEB)

    Nishino, Mizuki, E-mail: Mizuki_Nishino@DFCI.HARVARD.EDU [Department of Radiology, Brigham and Women’s Hospital, 450 Brookline Ave., Boston MA, 02215 (United States); Department of Imaging, Dana-Farber Cancer Institute, 450 Brookline Ave., Boston MA, 02215 (United States); Sacher, Adrian G.; Gandhi, Leena; Chen, Zhao; Akbay, Esra [Department of Medical Oncology and Department of Medicine Dana-Farber Cancer Institute and Brigham and Women’s Hospital 450 Brookline Ave., Boston MA, 02215 (United States); Fedorov, Andriy; Westin, Carl F.; Hatabu, Hiroto [Department of Radiology, Brigham and Women’s Hospital, 450 Brookline Ave., Boston MA, 02215 (United States); Johnson, Bruce E.; Hammerman, Peter; Wong, Kwok-kin [Department of Medical Oncology and Department of Medicine Dana-Farber Cancer Institute and Brigham and Women’s Hospital 450 Brookline Ave., Boston MA, 02215 (United States)

    2017-03-15

    Highlights: • Role of co-clinical studies in precision cancer medicine is increasingly recognized. • This study compared tumor volume in co-clinical trials of ALK-rearranged NSCLC. • Similarities and differences of tumor volume changes in mice and humans were noted. • The study provides insights to optimize murine co-clinical trial designs. - Abstract: Purpose: To evaluate and compare the volumetric tumor burden changes during crizotinib therapy in mice and human cohorts with ALK-rearranged non-small-cell lung cancer (NSCLC). Methods: Volumetric tumor burden was quantified on serial imaging studies in 8 bitransgenic mice with ALK-rearranged adenocarcinoma treated with crizotinib, and in 33 human subjects with ALK-rearranged NSCLC treated with crizotinib. The volumetric tumor burden changes and the time to maximal response were compared between mice and humans. Results: The median tumor volume decrease (%) at the maximal response was −40.4% (range: −79.5%–+11.7%) in mice, and −72.9% (range: −100%–+72%) in humans (Wilcoxon p = 0.03). The median time from the initiation of therapy to maximal response was 6 weeks in mice, and 15.7 weeks in humans. Overall volumetric response rate was 50% in mice and 97% in humans. Spider plots of tumor volume changes during therapy demonstrated durable responses in the human cohort, with a median time on therapy of 13.1 months. Conclusion: The present study described an initial attempt to evaluate quantitative tumor burden changes in co-clinical imaging studies of genomically-matched mice and human cohorts with ALK-rearranged NSCLC treated with crizotinib. Differences are noted in the degree of maximal volume response between the two cohorts in this well-established paradigm of targeted therapy, indicating a need for further studies to optimize co-clinical trial design and interpretation.

  18. Co-clinical quantitative tumor volume imaging in ALK-rearranged NSCLC treated with crizotinib

    International Nuclear Information System (INIS)

    Nishino, Mizuki; Sacher, Adrian G.; Gandhi, Leena; Chen, Zhao; Akbay, Esra; Fedorov, Andriy; Westin, Carl F.; Hatabu, Hiroto; Johnson, Bruce E.; Hammerman, Peter; Wong, Kwok-kin

    2017-01-01

    Highlights: • Role of co-clinical studies in precision cancer medicine is increasingly recognized. • This study compared tumor volume in co-clinical trials of ALK-rearranged NSCLC. • Similarities and differences of tumor volume changes in mice and humans were noted. • The study provides insights to optimize murine co-clinical trial designs. - Abstract: Purpose: To evaluate and compare the volumetric tumor burden changes during crizotinib therapy in mice and human cohorts with ALK-rearranged non-small-cell lung cancer (NSCLC). Methods: Volumetric tumor burden was quantified on serial imaging studies in 8 bitransgenic mice with ALK-rearranged adenocarcinoma treated with crizotinib, and in 33 human subjects with ALK-rearranged NSCLC treated with crizotinib. The volumetric tumor burden changes and the time to maximal response were compared between mice and humans. Results: The median tumor volume decrease (%) at the maximal response was −40.4% (range: −79.5%–+11.7%) in mice, and −72.9% (range: −100%–+72%) in humans (Wilcoxon p = 0.03). The median time from the initiation of therapy to maximal response was 6 weeks in mice, and 15.7 weeks in humans. Overall volumetric response rate was 50% in mice and 97% in humans. Spider plots of tumor volume changes during therapy demonstrated durable responses in the human cohort, with a median time on therapy of 13.1 months. Conclusion: The present study described an initial attempt to evaluate quantitative tumor burden changes in co-clinical imaging studies of genomically-matched mice and human cohorts with ALK-rearranged NSCLC treated with crizotinib. Differences are noted in the degree of maximal volume response between the two cohorts in this well-established paradigm of targeted therapy, indicating a need for further studies to optimize co-clinical trial design and interpretation.

  19. Low power digital communication in implantable devices using volume conduction of biological tissues.

    Science.gov (United States)

    Yao, Ning; Lee, Heung-No; Sclabassi, R J; Sun, Mingui

    2006-01-01

    This work investigates the data communication problem of implantable devices using fundamental theories in communications. We utilize the volume conduction property of biological tissues to establish a digital communications link. Data obtained through animal experiments are used to analyze the time and frequency response of the volume conduction channel as well as to characterize the biological signals and noises present in the system. A low power bandwidth efficient channel-coded modulation scheme is proposed to conserve battery power and reduce the health risks associated.

  20. Quantitative model analysis with diverse biological data: applications in developmental pattern formation.

    Science.gov (United States)

    Pargett, Michael; Umulis, David M

    2013-07-15

    Mathematical modeling of transcription factor and signaling networks is widely used to understand if and how a mechanism works, and to infer regulatory interactions that produce a model consistent with the observed data. Both of these approaches to modeling are informed by experimental data, however, much of the data available or even acquirable are not quantitative. Data that is not strictly quantitative cannot be used by classical, quantitative, model-based analyses that measure a difference between the measured observation and the model prediction for that observation. To bridge the model-to-data gap, a variety of techniques have been developed to measure model "fitness" and provide numerical values that can subsequently be used in model optimization or model inference studies. Here, we discuss a selection of traditional and novel techniques to transform data of varied quality and enable quantitative comparison with mathematical models. This review is intended to both inform the use of these model analysis methods, focused on parameter estimation, and to help guide the choice of method to use for a given study based on the type of data available. Applying techniques such as normalization or optimal scaling may significantly improve the utility of current biological data in model-based study and allow greater integration between disparate types of data. Copyright © 2013 Elsevier Inc. All rights reserved.

  1. Quantitative modeling of gene networks of biological systems using fuzzy Petri nets and fuzzy sets

    Directory of Open Access Journals (Sweden)

    Raed I. Hamed

    2018-01-01

    Full Text Available Quantitative demonstrating of organic frameworks has turned into an essential computational methodology in the configuration of novel and investigation of existing natural frameworks. Be that as it may, active information that portrays the framework's elements should be known keeping in mind the end goal to get pertinent results with the routine displaying strategies. This information is frequently robust or even difficult to get. Here, we exhibit a model of quantitative fuzzy rational demonstrating approach that can adapt to obscure motor information and hence deliver applicable results despite the fact that dynamic information is fragmented or just dubiously characterized. Besides, the methodology can be utilized as a part of the blend with the current cutting edge quantitative demonstrating strategies just in specific parts of the framework, i.e., where the data are absent. The contextual analysis of the methodology suggested in this paper is performed on the model of nine-quality genes. We propose a kind of FPN model in light of fuzzy sets to manage the quantitative modeling of biological systems. The tests of our model appear that the model is practical and entirely powerful for information impersonation and thinking of fuzzy expert frameworks.

  2. Three-Dimensional Photography for Quantitative Assessment of Penile Volume-Loss Deformities in Peyronie's Disease.

    Science.gov (United States)

    Margolin, Ezra J; Mlynarczyk, Carrie M; Mulhall, John P; Stember, Doron S; Stahl, Peter J

    2017-06-01

    Non-curvature penile deformities are prevalent and bothersome manifestations of Peyronie's disease (PD), but the quantitative metrics that are currently used to describe these deformities are inadequate and non-standardized, presenting a barrier to clinical research and patient care. To introduce erect penile volume (EPV) and percentage of erect penile volume loss (percent EPVL) as novel metrics that provide detailed quantitative information about non-curvature penile deformities and to study the feasibility and reliability of three-dimensional (3D) photography for measurement of quantitative penile parameters. We constructed seven penis models simulating deformities found in PD. The 3D photographs of each model were captured in triplicate by four observers using a 3D camera. Computer software was used to generate automated measurements of EPV, percent EPVL, penile length, minimum circumference, maximum circumference, and angle of curvature. The automated measurements were statistically compared with measurements obtained using water-displacement experiments, a tape measure, and a goniometer. Accuracy of 3D photography for average measurements of all parameters compared with manual measurements; inter-test, intra-observer, and inter-observer reliabilities of EPV and percent EPVL measurements as assessed by the intraclass correlation coefficient. The 3D images were captured in a median of 52 seconds (interquartile range = 45-61). On average, 3D photography was accurate to within 0.3% for measurement of penile length. It overestimated maximum and minimum circumferences by averages of 4.2% and 1.6%, respectively; overestimated EPV by an average of 7.1%; and underestimated percent EPVL by an average of 1.9%. All inter-test, inter-observer, and intra-observer intraclass correlation coefficients for EPV and percent EPVL measurements were greater than 0.75, reflective of excellent methodologic reliability. By providing highly descriptive and reliable measurements of

  3. Flexible automated approach for quantitative liquid handling of complex biological samples.

    Science.gov (United States)

    Palandra, Joe; Weller, David; Hudson, Gary; Li, Jeff; Osgood, Sarah; Hudson, Emily; Zhong, Min; Buchholz, Lisa; Cohen, Lucinda H

    2007-11-01

    A fully automated protein precipitation technique for biological sample preparation has been developed for the quantitation of drugs in various biological matrixes. All liquid handling during sample preparation was automated using a Hamilton MicroLab Star Robotic workstation, which included the preparation of standards and controls from a Watson laboratory information management system generated work list, shaking of 96-well plates, and vacuum application. Processing time is less than 30 s per sample or approximately 45 min per 96-well plate, which is then immediately ready for injection onto an LC-MS/MS system. An overview of the process workflow is discussed, including the software development. Validation data are also provided, including specific liquid class data as well as comparative data of automated vs manual preparation using both quality controls and actual sample data. The efficiencies gained from this automated approach are described.

  4. Automated quantitative assessment of proteins' biological function in protein knowledge bases.

    Science.gov (United States)

    Mayr, Gabriele; Lepperdinger, Günter; Lackner, Peter

    2008-01-01

    Primary protein sequence data are archived in databases together with information regarding corresponding biological functions. In this respect, UniProt/Swiss-Prot is currently the most comprehensive collection and it is routinely cross-examined when trying to unravel the biological role of hypothetical proteins. Bioscientists frequently extract single entries and further evaluate those on a subjective basis. In lieu of a standardized procedure for scoring the existing knowledge regarding individual proteins, we here report about a computer-assisted method, which we applied to score the present knowledge about any given Swiss-Prot entry. Applying this quantitative score allows the comparison of proteins with respect to their sequence yet highlights the comprehension of functional data. pfs analysis may be also applied for quality control of individual entries or for database management in order to rank entry listings.

  5. Automated Quantitative Assessment of Proteins' Biological Function in Protein Knowledge Bases

    Directory of Open Access Journals (Sweden)

    Gabriele Mayr

    2008-01-01

    Full Text Available Primary protein sequence data are archived in databases together with information regarding corresponding biological functions. In this respect, UniProt/Swiss-Prot is currently the most comprehensive collection and it is routinely cross-examined when trying to unravel the biological role of hypothetical proteins. Bioscientists frequently extract single entries and further evaluate those on a subjective basis. In lieu of a standardized procedure for scoring the existing knowledge regarding individual proteins, we here report about a computer-assisted method, which we applied to score the present knowledge about any given Swiss-Prot entry. Applying this quantitative score allows the comparison of proteins with respect to their sequence yet highlights the comprehension of functional data. pfs analysis may be also applied for quality control of individual entries or for database management in order to rank entry listings.

  6. Life at the Common Denominator: Mechanistic and Quantitative Biology for the Earth and Space Sciences

    Science.gov (United States)

    Hoehler, Tori M.

    2010-01-01

    The remarkable challenges and possibilities of the coming few decades will compel the biogeochemical and astrobiological sciences to characterize the interactions between biology and its environment in a fundamental, mechanistic, and quantitative fashion. The clear need for integrative and scalable biology-environment models is exemplified in the Earth sciences by the challenge of effectively addressing anthropogenic global change, and in the space sciences by the challenge of mounting a well-constrained yet sufficiently adaptive and inclusive search for life beyond Earth. Our understanding of the life-planet interaction is still, however, largely empirical. A variety of approaches seek to move from empirical to mechanistic descriptions. One approach focuses on the relationship between biology and energy, which is at once universal (all life requires energy), unique (life manages energy flow in a fashion not seen in abiotic systems), and amenable to characterization and quantification in thermodynamic terms. Simultaneously, a focus on energy flow addresses a critical point of interface between life and its geological, chemical, and physical environment. Characterizing and quantifying this relationship for life on Earth will support the development of integrative and predictive models for biology-environment dynamics. Understanding this relationship at its most fundamental level holds potential for developing concepts of habitability and biosignatures that can optimize astrobiological exploration strategies and are extensible to all life.

  7. Quantitative computational models of molecular self-assembly in systems biology.

    Science.gov (United States)

    Thomas, Marcus; Schwartz, Russell

    2017-05-23

    Molecular self-assembly is the dominant form of chemical reaction in living systems, yet efforts at systems biology modeling are only beginning to appreciate the need for and challenges to accurate quantitative modeling of self-assembly. Self-assembly reactions are essential to nearly every important process in cell and molecular biology and handling them is thus a necessary step in building comprehensive models of complex cellular systems. They present exceptional challenges, however, to standard methods for simulating complex systems. While the general systems biology world is just beginning to deal with these challenges, there is an extensive literature dealing with them for more specialized self-assembly modeling. This review will examine the challenges of self-assembly modeling, nascent efforts to deal with these challenges in the systems modeling community, and some of the solutions offered in prior work on self-assembly specifically. The review concludes with some consideration of the likely role of self-assembly in the future of complex biological system models more generally.

  8. Study on methods of quantitative analysis of the biological thin samples in EM X-ray microanalysis

    International Nuclear Information System (INIS)

    Zhang Detian; Zhang Xuemin; He Kun; Yang Yi; Zhang Sa; Wang Baozhen

    2000-01-01

    Objective: To study the methods of quantitative analysis of the biological thin samples. Methods: Hall theory was used to study the qualitative analysis, background subtraction, peel off overlap peaks; external radiation and aberrance of spectra. Results: The results of reliable qualitative analysis and precise quantitative analysis were achieved. Conclusion: The methods for analysis of the biological thin samples in EM X-ray microanalysis can be used in biomedical research

  9. Quantitative phase imaging and differential interference contrast imaging for biological TEM

    International Nuclear Information System (INIS)

    Allman, B.E.; McMahon, P.J.; Barone-Nugent, E.D.; Nugent, E.D.

    2002-01-01

    Full text: Phase microscopy is a central technique in science. An experienced microscopist uses this effect to visualise (edge) structure within transparent samples by slightly defocusing the microscope. Although widespread in optical microscopy, phase contrast transmission electron microscopy (TEM) has not been widely adopted. TEM for biological specimens has largely relied on staining techniques to yield sufficient contrast. We show here a simple method for quantitative TEM phase microscopy that quantifies this phase contrast effect. Starting with conventional, digital, bright field images of the sample, our algorithm provides quantitative phase information independent of the sample's bright field intensity image. We present TEM phase images of a range of stained and unstained, biological and material science specimens. This independent phase and intensity information is then used to emulate a range of phase visualisation images familiar to optical microscopy, e.g. differential interference contrast. The phase images contain features not visible with the other imaging modalities. Further, if the TEM samples have been prepared on a microtome to a uniform thickness, the phase information can be converted into refractive index structure of the specimen. Copyright (2002) Australian Society for Electron Microscopy Inc

  10. Methods for quantitative measurement of tooth wear using the area and volume of virtual model cusps.

    Science.gov (United States)

    Kim, Soo-Hyun; Park, Young-Seok; Kim, Min-Kyoung; Kim, Sulhee; Lee, Seung-Pyo

    2018-04-01

    Clinicians must examine tooth wear to make a proper diagnosis. However, qualitative methods of measuring tooth wear have many disadvantages. Therefore, this study aimed to develop and evaluate quantitative parameters using the cusp area and volume of virtual dental models. The subjects of this study were the same virtual models that were used in our former study. The same age group classification and new tooth wear index (NTWI) scoring system were also reused. A virtual occlusal plane was generated with the highest cusp points and lowered vertically from 0.2 to 0.8 mm to create offset planes. The area and volume of each cusp was then measured and added together. In addition to the former analysis, the differential features of each cusp were analyzed. The scores of the new parameters differentiated the age and NTWI groups better than those analyzed in the former study. The Spearman ρ coefficients between the total area and the area of each cusp also showed higher scores at the levels of 0.6 mm (0.6A) and 0.8A. The mesiolingual cusp (MLC) showed a statistically significant difference ( P <0.01) from the other cusps in the paired t -test. Additionally, the MLC exhibited the highest percentage of change at 0.6A in some age and NTWI groups. Regarding the age groups, the MLC showed the highest score in groups 1 and 2. For the NTWI groups, the MLC was not significantly different in groups 3 and 4. These results support the proposal that the lingual cusp exhibits rapid wear because it serves as a functional cusp. Although this study has limitations due to its cross-sectional nature, it suggests better quantitative parameters and analytical tools for the characteristics of cusp wear.

  11. Quantitation of biological retinoids by high-pressure liquid chromatography: primary internal standardization using tritiated retinoids

    International Nuclear Information System (INIS)

    Cullum, M.E.; Zile, M.H.

    1986-01-01

    A single method is described for quantitation of 14 retinoids found in biological material. The method consists of reversed-phase HPLC, internal standardization, and carrier extraction procedures with three synthetic retinoids. Primary standardization of HPLC uv detector is achieved using tritiated all-trans-retinoic acid, all-trans-retinol, all-trans-retinyl palmitate, and all-trans-retinyl acetate. Extraction methods are standardized by correlating the uv absorbance of retinoids at 340 nm with radioactivity of tritiated retinoids of known specific activity. Quantitation of 10 pg of tritiated or 5 ng of nonradioactive retinoid per 0.1 g sample in a polarity range from 4-oxo-retinoic acid to retinyl stearate can be achieved in a single, 50-min chromatographic run. A single HPLC pump, a C 18 reversed-phased analytical column, a multistep three-solvent gradient, and inexpensive solvents based on methanol, water, and chloroform comprise this cost-effective chromatographic system. Our primary standardization method allows investigators employing different procedures to compare results between laboratories by standardizing the HPLC uv detector with commercially available tritiated retinoids. With this method we were able to quantitate nanomolar amounts of endogenous retinoic acids and retinyl esters, that HPLC uv only conditions usually would not detect in the circulation and liver of rats under physiological conditions

  12. Determination of quantitative tissue composition by iterative reconstruction on 3D DECT volumes

    Energy Technology Data Exchange (ETDEWEB)

    Magnusson, Maria [Linkoeping Univ. (Sweden). Dept. of Electrical Engineering; Linkoeping Univ. (Sweden). Dept. of Medical and Health Sciences, Radiation Physics; Linkoeping Univ. (Sweden). Center for Medical Image Science and Visualization (CMIV); Malusek, Alexandr [Linkoeping Univ. (Sweden). Dept. of Medical and Health Sciences, Radiation Physics; Linkoeping Univ. (Sweden). Center for Medical Image Science and Visualization (CMIV); Nuclear Physics Institute AS CR, Prague (Czech Republic). Dept. of Radiation Dosimetry; Muhammad, Arif [Linkoeping Univ. (Sweden). Dept. of Medical and Health Sciences, Radiation Physics; Carlsson, Gudrun Alm [Linkoeping Univ. (Sweden). Dept. of Medical and Health Sciences, Radiation Physics; Linkoeping Univ. (Sweden). Center for Medical Image Science and Visualization (CMIV)

    2011-07-01

    Quantitative tissue classification using dual-energy CT has the potential to improve accuracy in radiation therapy dose planning as it provides more information about material composition of scanned objects than the currently used methods based on single-energy CT. One problem that hinders successful application of both single- and dual-energy CT is the presence of beam hardening and scatter artifacts in reconstructed data. Current pre- and post-correction methods used for image reconstruction often bias CT attenuation values and thus limit their applicability for quantitative tissue classification. Here we demonstrate simulation studies with a novel iterative algorithm that decomposes every soft tissue voxel into three base materials: water, protein, and adipose. The results demonstrate that beam hardening artifacts can effectively be removed and accurate estimation of mass fractions of each base material can be achieved. Our iterative algorithm starts with calculating parallel projections on two previously reconstructed DECT volumes reconstructed from fan-beam or helical projections with small conebeam angle. The parallel projections are then used in an iterative loop. Future developments include segmentation of soft and bone tissue and subsequent determination of bone composition. (orig.)

  13. Improved dose–volume histogram estimates for radiopharmaceutical therapy by optimizing quantitative SPECT reconstruction parameters

    International Nuclear Information System (INIS)

    Cheng Lishui; Hobbs, Robert F; Sgouros, George; Frey, Eric C; Segars, Paul W

    2013-01-01

    In radiopharmaceutical therapy, an understanding of the dose distribution in normal and target tissues is important for optimizing treatment. Three-dimensional (3D) dosimetry takes into account patient anatomy and the nonuniform uptake of radiopharmaceuticals in tissues. Dose–volume histograms (DVHs) provide a useful summary representation of the 3D dose distribution and have been widely used for external beam treatment planning. Reliable 3D dosimetry requires an accurate 3D radioactivity distribution as the input. However, activity distribution estimates from SPECT are corrupted by noise and partial volume effects (PVEs). In this work, we systematically investigated OS-EM based quantitative SPECT (QSPECT) image reconstruction in terms of its effect on DVHs estimates. A modified 3D NURBS-based Cardiac-Torso (NCAT) phantom that incorporated a non-uniform kidney model and clinically realistic organ activities and biokinetics was used. Projections were generated using a Monte Carlo (MC) simulation; noise effects were studied using 50 noise realizations with clinical count levels. Activity images were reconstructed using QSPECT with compensation for attenuation, scatter and collimator–detector response (CDR). Dose rate distributions were estimated by convolution of the activity image with a voxel S kernel. Cumulative DVHs were calculated from the phantom and QSPECT images and compared both qualitatively and quantitatively. We found that noise, PVEs, and ringing artifacts due to CDR compensation all degraded histogram estimates. Low-pass filtering and early termination of the iterative process were needed to reduce the effects of noise and ringing artifacts on DVHs, but resulted in increased degradations due to PVEs. Large objects with few features, such as the liver, had more accurate histogram estimates and required fewer iterations and more smoothing for optimal results. Smaller objects with fine details, such as the kidneys, required more iterations and less

  14. Evaluation of fourier transform profilometry performance: quantitative waste volume determination under simulated Hanford waste tank conditions

    International Nuclear Information System (INIS)

    Jang, Ping-Rey; Leone, Teresa; Long, Zhiling; Mott, Melissa A.; Perry Norton, O.; Okhuysen, Walter P.; Monts, David L.

    2007-01-01

    The Hanford Site is currently in the process of an extensive effort to empty and close its radioactive single-shell and double-shell waste storage tanks. Before this can be accomplished, it is necessary to know how much residual material is left in a given waste tank and the chemical makeup of the residue. The objective of Mississippi State University's Institute for Clean Energy Technology's (ICET) efforts is to develop, fabricate, and deploy inspection tools for the Hanford waste tanks that will (1) be remotely operable; (2) provide quantitative information on the amount of wastes remaining; and (3) provide information on the spatial distribution of chemical and radioactive species of interest. A collaborative arrangement has been established with the Hanford Site to develop probe-based inspection systems for deployment in the waste tanks. ICET is currently developing an in-tank inspection system based on Fourier Transform Profilometry, FTP. FTP is a non-contact, 3-D shape measurement technique. By projecting a fringe pattern onto a target surface and observing its deformation due to surface irregularities from a different view angle, FTP is capable of determining the height (depth) distribution (and hence volume distribution) of the target surface, thus reproducing the profile of the target accurately under a wide variety of conditions. Hence FTP has the potential to be utilized for quantitative determination of residual wastes within Hanford waste tanks. We have completed a preliminary performance evaluation of FTP in order to document the accuracy, precision, and operator dependence (minimal) of FTP under conditions similar to those that can be expected to pertain within Hanford waste tanks. Based on a Hanford C-200 series tank with camera access through a riser with significant offset relative to the centerline, we devised a testing methodology that encompassed a range of obstacles likely to be encountered 'in tank'. These test objects were inspected by use

  15. Improved dose-volume histogram estimates for radiopharmaceutical therapy by optimizing quantitative SPECT reconstruction parameters

    Science.gov (United States)

    Cheng, Lishui; Hobbs, Robert F.; Segars, Paul W.; Sgouros, George; Frey, Eric C.

    2013-06-01

    In radiopharmaceutical therapy, an understanding of the dose distribution in normal and target tissues is important for optimizing treatment. Three-dimensional (3D) dosimetry takes into account patient anatomy and the nonuniform uptake of radiopharmaceuticals in tissues. Dose-volume histograms (DVHs) provide a useful summary representation of the 3D dose distribution and have been widely used for external beam treatment planning. Reliable 3D dosimetry requires an accurate 3D radioactivity distribution as the input. However, activity distribution estimates from SPECT are corrupted by noise and partial volume effects (PVEs). In this work, we systematically investigated OS-EM based quantitative SPECT (QSPECT) image reconstruction in terms of its effect on DVHs estimates. A modified 3D NURBS-based Cardiac-Torso (NCAT) phantom that incorporated a non-uniform kidney model and clinically realistic organ activities and biokinetics was used. Projections were generated using a Monte Carlo (MC) simulation; noise effects were studied using 50 noise realizations with clinical count levels. Activity images were reconstructed using QSPECT with compensation for attenuation, scatter and collimator-detector response (CDR). Dose rate distributions were estimated by convolution of the activity image with a voxel S kernel. Cumulative DVHs were calculated from the phantom and QSPECT images and compared both qualitatively and quantitatively. We found that noise, PVEs, and ringing artifacts due to CDR compensation all degraded histogram estimates. Low-pass filtering and early termination of the iterative process were needed to reduce the effects of noise and ringing artifacts on DVHs, but resulted in increased degradations due to PVEs. Large objects with few features, such as the liver, had more accurate histogram estimates and required fewer iterations and more smoothing for optimal results. Smaller objects with fine details, such as the kidneys, required more iterations and less

  16. Quantitative utilization of prior biological knowledge in the Bayesian network modeling of gene expression data

    Directory of Open Access Journals (Sweden)

    Gao Shouguo

    2011-08-01

    Full Text Available Abstract Background Bayesian Network (BN is a powerful approach to reconstructing genetic regulatory networks from gene expression data. However, expression data by itself suffers from high noise and lack of power. Incorporating prior biological knowledge can improve the performance. As each type of prior knowledge on its own may be incomplete or limited by quality issues, integrating multiple sources of prior knowledge to utilize their consensus is desirable. Results We introduce a new method to incorporate the quantitative information from multiple sources of prior knowledge. It first uses the Naïve Bayesian classifier to assess the likelihood of functional linkage between gene pairs based on prior knowledge. In this study we included cocitation in PubMed and schematic similarity in Gene Ontology annotation. A candidate network edge reservoir is then created in which the copy number of each edge is proportional to the estimated likelihood of linkage between the two corresponding genes. In network simulation the Markov Chain Monte Carlo sampling algorithm is adopted, and samples from this reservoir at each iteration to generate new candidate networks. We evaluated the new algorithm using both simulated and real gene expression data including that from a yeast cell cycle and a mouse pancreas development/growth study. Incorporating prior knowledge led to a ~2 fold increase in the number of known transcription regulations recovered, without significant change in false positive rate. In contrast, without the prior knowledge BN modeling is not always better than a random selection, demonstrating the necessity in network modeling to supplement the gene expression data with additional information. Conclusion our new development provides a statistical means to utilize the quantitative information in prior biological knowledge in the BN modeling of gene expression data, which significantly improves the performance.

  17. Quantitative X-ray analysis of biological fluids: the microdroplet technique

    International Nuclear Information System (INIS)

    Roinel, N.

    1988-01-01

    X-ray microanalysis can be used to quantitatively determine the elemental composition of microvolumes of biological fluids. This article describes the various steps in preparation of microdroplets for analysis: The manufacturing of micropipettes, the preparation of the specimen support, the deposition of droplets on the support, shock-freezing, and lyophilization. Examples of common artifacts (incomplete rehydration prior to freezing or partial rehydration after lyophilization) are demonstrated. Analysis can be carried out either by wavelength-dispersive analysis, which is the most sensitive method, or by energy-dispersive analysis, which is more commonly available. The minimum detectable concentration is 0.05 mmol.liter-1 for 0.1-nl samples analyzed by wavelength-dispersive spectrometry and 0.5-1 mmol.liter-1 for samples analyzed by energy-dispersive spectrometry. A major problem, especially in wavelength-dispersive analysis, where high beam currents are used, is radiation damage to the specimen; in particular chloride (but also other elements) can be lost. Quantitative analysis requires the use of standard solutions with elemental concentration in the same range as those present in the specimen

  18. Quantitative generalized ratiometric fluorescence spectroscopy for turbid media based on probe encapsulated by biologically localized embedding

    International Nuclear Information System (INIS)

    Yan, Xiu-Fang; Chen, Zeng-Ping; Cui, Yin-Yin; Hu, Yuan-Liang; Yu, Ru-Qin

    2016-01-01

    PEBBLE (probe encapsulated by biologically localized embedding) nanosensor encapsulating an intensity-based fluorescence indicator and an inert reference fluorescence dye inside the pores of stable matrix can be used as a generalized wavelength-ratiometric probe. However, the lack of an efficient quantitative model render the choices of inert reference dyes and intensity-based fluorescence indicators used in PEBBLEs based generalized wavelength-ratiometric probes rather limited. In this contribution, an extended quantitative fluorescence model was derived specifically for generalized wavelength-ratiometric probes based on PEBBLE technique (QFM GRP ) with a view to simplify the design of PEBBLEs and hence further extend their application potentials. The effectiveness of QFM GRP has been tested on the quantitative determination of free Ca 2+ in both simulated and real turbid media using a Ca 2+ sensitive PEBBLE nanosensor encapsulating Rhod-2 and eosin B inside the micropores of stable polyacrylamide matrix. Experimental results demonstrated that QFM GRP could realize precise and accurate quantification of free Ca 2+ in turbid samples, even though there is serious overlapping between the fluorescence excitation peaks of eosin B and Ca 2+ bound Rhod-2. The average relative predictive error value of QFM GRP for the test simulated turbid samples was 5.9%, about 2–4 times lower than the corresponding values of partial least squares calibration model and the empirical ratiometric model based on the ratio of fluorescence intensities at the excitation peaks of Ca 2+ bound Rhod-2 and eosin B. The recovery rates of QFM GRP for the real and spiked turbid samples varied from 93.1% to 101%, comparable to the corresponding results of atomic absorption spectrometry. - Highlights: • An advanced model was derived for generalized wavelength-ratiometric PEBBLEs. • The model can simplify the design of generalized wavelength-ratiometric PEBBLEs. • The model realized accurate

  19. A comparison of quantitative reconstruction techniques for PIXE-tomography analysis applied to biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Beasley, D.G., E-mail: dgbeasley@ctn.ist.utl.pt [IST/C2TN, Universidade de Lisboa, Campus Tecnológico e Nuclear, E.N.10, 2686-953 Sacavém (Portugal); Alves, L.C. [IST/C2TN, Universidade de Lisboa, Campus Tecnológico e Nuclear, E.N.10, 2686-953 Sacavém (Portugal); Barberet, Ph.; Bourret, S.; Devès, G.; Gordillo, N.; Michelet, C. [Univ. Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France); Le Trequesser, Q. [Univ. Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France); Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB, UPR9048) CNRS, Université de Bordeaux, 87 avenue du Dr. A. Schweitzer, Pessac F-33608 (France); Marques, A.C. [IST/IPFN, Universidade de Lisboa, Campus Tecnológico e Nuclear, E.N.10, 2686-953 Sacavém (Portugal); Seznec, H. [Univ. Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France); Silva, R.C. da [IST/IPFN, Universidade de Lisboa, Campus Tecnológico e Nuclear, E.N.10, 2686-953 Sacavém (Portugal)

    2014-07-15

    The tomographic reconstruction of biological specimens requires robust algorithms, able to deal with low density contrast and low element concentrations. At the IST/ITN microprobe facility new GPU-accelerated reconstruction software, JPIXET, has been developed, which can significantly increase the speed of quantitative reconstruction of Proton Induced X-ray Emission Tomography (PIXE-T) data. It has a user-friendly graphical user interface for pre-processing, data analysis and reconstruction of PIXE-T and Scanning Transmission Ion Microscopy Tomography (STIM-T). The reconstruction of PIXE-T data is performed using either an algorithm based on a GPU-accelerated version of the Maximum Likelihood Expectation Maximisation (MLEM) method or a GPU-accelerated version of the Discrete Image Space Reconstruction Algorithm (DISRA) (Sakellariou (2001) [2]). The original DISRA, its accelerated version, and the MLEM algorithm, were compared for the reconstruction of a biological sample of Caenorhabditis elegans – a small worm. This sample was analysed at the microbeam line of the AIFIRA facility of CENBG, Bordeaux. A qualitative PIXE-T reconstruction was obtained using the CENBG software package TomoRebuild (Habchi et al. (2013) [6]). The effects of pre-processing and experimental conditions on the elemental concentrations are discussed.

  20. The effect of volume-of-interest misregistration on quantitative planar activity and dose estimation

    International Nuclear Information System (INIS)

    Song, N; Frey, E C; He, B

    2010-01-01

    In targeted radionuclide therapy (TRT), dose estimation is essential for treatment planning and tumor dose response studies. Dose estimates are typically based on a time series of whole-body conjugate view planar or SPECT scans of the patient acquired after administration of a planning dose. Quantifying the activity in the organs from these studies is an essential part of dose estimation. The quantitative planar (QPlanar) processing method involves accurate compensation for image degrading factors and correction for organ and background overlap via the combination of computational models of the image formation process and 3D volumes of interest defining the organs to be quantified. When the organ VOIs are accurately defined, the method intrinsically compensates for attenuation, scatter and partial volume effects, as well as overlap with other organs and the background. However, alignment between the 3D organ volume of interest (VOIs) used in QPlanar processing and the true organ projections in the planar images is required. The aim of this research was to study the effects of VOI misregistration on the accuracy and precision of organ activity estimates obtained using the QPlanar method. In this work, we modeled the degree of residual misregistration that would be expected after an automated registration procedure by randomly misaligning 3D SPECT/CT images, from which the VOI information was derived, and planar images. Mutual information-based image registration was used to align the realistic simulated 3D SPECT images with the 2D planar images. The residual image misregistration was used to simulate realistic levels of misregistration and allow investigation of the effects of misregistration on the accuracy and precision of the QPlanar method. We observed that accurate registration is especially important for small organs or ones with low activity concentrations compared to neighboring organs. In addition, residual misregistration gave rise to a loss of precision

  1. Residual DNA analysis in biologics development: review of measurement and quantitation technologies and future directions.

    Science.gov (United States)

    Wang, Xing; Morgan, Donna M; Wang, Gan; Mozier, Ned M

    2012-02-01

    Residual DNA (rDNA) is comprised of deoxyribonucleic acid (DNA) fragments and longer length molecules originating from the host organism that may be present in samples from recombinant biological processes. Although similar in basic structural base pair units, rDNA may exist in different sizes and physical forms. Interest in measuring rDNA in recombinant products is based primarily on demonstration of effective purification during manufacturing, but also on some hypothetical concerns that, in rare cases, depending on the host expression system, some DNA sequences may be potentially infectious or oncogenic (e.g., HIV virus and the Ras oncogene, respectively). Recent studies suggest that a sequence known as long interspersed nucleotide element-1 (LINE-1), widely distributed in the mammalian genome, is active as a retrotransposon that can be transcribed to RNA, reverse-transcribed into DNA and inserts into a new site in genome. This integration process could potentially disrupt critical gene functions or induce tumorigenesis in mammals. Genomic DNA from microbial sources, on the other hand, could add to risk of immunogenicity to the target recombinant protein being expressed, due to the high CpG content and unmethylated DNA sequence. For these and other reasons, it is necessary for manufacturers to show clearance of DNA throughout production processes and to confirm low levels in the final drug substance using an appropriately specific and quantitative analytical method. The heterogeneity of potential rDNA sequences that might be makes the testing of all potential analytes challenging. The most common methodology for rDNA quantitation used currently is real-time polymerase chain reaction (RT-PCR), a robust and proven technology. Like most rDNA quantitation methods, the specificity of RT-PCR is limited by the sequences to which the primers are directed. To address this, primase-based whole genome amplification is introduced herein. This paper will review the recent

  2. Quantitative Analysis of Variability and Uncertainty in Environmental Data and Models. Volume 1. Theory and Methodology Based Upon Bootstrap Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Frey, H. Christopher [North Carolina State University, Raleigh, NC (United States); Rhodes, David S. [North Carolina State University, Raleigh, NC (United States)

    1999-04-30

    This is Volume 1 of a two-volume set of reports describing work conducted at North Carolina State University sponsored by Grant Number DE-FG05-95ER30250 by the U.S. Department of Energy. The title of the project is “Quantitative Analysis of Variability and Uncertainty in Acid Rain Assessments.” The work conducted under sponsorship of this grant pertains primarily to two main topics: (1) development of new methods for quantitative analysis of variability and uncertainty applicable to any type of model; and (2) analysis of variability and uncertainty in the performance, emissions, and cost of electric power plant combustion-based NOx control technologies. These two main topics are reported separately in Volumes 1 and 2.

  3. Mixing subattolitre volumes in a quantitative and highly parallel manner with soft matter nanofluidics

    DEFF Research Database (Denmark)

    Christensen, Sune M.; Bolinger, Pierre-Yves; Hatzakis, Nikos

    2012-01-01

    Handling and mixing ultrasmall volumes of reactants in parallel can increase the throughput and complexity of screening assays while simultaneously reducing reagent consumption. Microfabricated silicon and plastic can provide reliable fluidic devices, but cannot typically handle total volumes sma...

  4. Liquid chromatography coupled with tandem mass spectrometry for the quantitative analysis of anticancer drugs in biological matrices

    NARCIS (Netherlands)

    Stokvis, Ellen

    2004-01-01

    In this thesis, the development and validation of liquid chromatography tandem mass spectrometric (LC-MS/MS) methods for the quantitative bioanalysis of anticancer drugs are described. The monitoring of these drugs in biological fluids and tissues is important during both pre-clinical and clinical

  5. Volume measurement of the leg with the depth camera for quantitative evaluation of edema

    Science.gov (United States)

    Kiyomitsu, Kaoru; Kakinuma, Akihiro; Takahashi, Hiroshi; Kamijo, Naohiro; Ogawa, Keiko; Tsumura, Norimichi

    2017-02-01

    Volume measurement of the leg is important in the evaluation of leg edema. Recently, method for measurement by using a depth camera is proposed. However, many depth cameras are expensive. Therefore, we propose a method using Microsoft Kinect. We obtain a point cloud of the leg by Kinect Fusion technique and calculate the volume. We measured the volume of leg for three healthy students during three days. In each measurement, the increase of volume was confirmed from morning to evening. It is known that the volume of leg is increased in doing office work. Our experimental results meet this expectation.

  6. Quantitative Modeling of Membrane Transport and Anisogamy by Small Groups Within a Large-Enrollment Organismal Biology Course

    Directory of Open Access Journals (Sweden)

    Eric S. Haag

    2016-12-01

    Full Text Available Quantitative modeling is not a standard part of undergraduate biology education, yet is routine in the physical sciences. Because of the obvious biophysical aspects, classes in anatomy and physiology offer an opportunity to introduce modeling approaches to the introductory curriculum. Here, we describe two in-class exercises for small groups working within a large-enrollment introductory course in organismal biology. Both build and derive biological insights from quantitative models, implemented using spreadsheets. One exercise models the evolution of anisogamy (i.e., small sperm and large eggs from an initial state of isogamy. Groups of four students work on Excel spreadsheets (from one to four laptops per group. The other exercise uses an online simulator to generate data related to membrane transport of a solute, and a cloud-based spreadsheet to analyze them. We provide tips for implementing these exercises gleaned from two years of experience.

  7. Advances in radiation biology: Relative radiation sensitivities of human organ systems. Volume 12

    International Nuclear Information System (INIS)

    Lett, J.T.; Altman, K.I.; Ehmann, U.K.; Cox, A.B.

    1987-01-01

    This volume is a thematically focused issue of Advances in Radiation Biology. The topic surveyed is relative radiosensitivity of human organ systems. Topics considered include relative radiosensitivities of the thymus, spleen, and lymphohemopoietic systems; relative radiosensitivities of the small and large intestine; relative rediosensitivities of the oral cavity, larynx, pharynx, and esophagus; relative radiation sensitivity of the integumentary system; dose response of the epidermal; microvascular, and dermal populations; relative radiosensitivity of the human lung; relative radiosensitivity of fetal tissues; and tolerance of the central and peripheral nervous system to therapeutic irradiation

  8. Advances in radiation biology: Relative radiation sensitivities of human organ systems. Volume 12

    Energy Technology Data Exchange (ETDEWEB)

    Lett, J.T.; Altman, K.I.; Ehmann, U.K.; Cox, A.B.

    1987-01-01

    This volume is a thematically focused issue of Advances in Radiation Biology. The topic surveyed is relative radiosensitivity of human organ systems. Topics considered include relative radiosensitivities of the thymus, spleen, and lymphohemopoietic systems; relative radiosensitivities of the small and large intestine; relative rediosensitivities of the oral cavity, larynx, pharynx, and esophagus; relative radiation sensitivity of the integumentary system; dose response of the epidermal; microvascular, and dermal populations; relative radiosensitivity of the human lung; relative radiosensitivity of fetal tissues; and tolerance of the central and peripheral nervous system to therapeutic irradiation.

  9. Biological intrusion barriers for large-volume waste-disposal sites

    International Nuclear Information System (INIS)

    Hakonson, T.E.; Cline, J.F.; Rickard, W.H.

    1982-01-01

    intrusion of plants and animals into shallow land burial sites with subsequent mobilization of toxic and radiotoxic materials has occured. Based on recent pathway modeling studies, such intrusions can contribute to the dose received by man. This paper describes past work on developing biological intrusion barrier systems for application to large volume waste site stabilization. State-of-the-art concepts employing rock and chemical barriers are discussed relative to long term serviceability and cost of application. The interaction of bio-intrusion barrier systems with other processes affecting trench cover stability are discussed to ensure that trench cover designs minimize the potential dose to man. 3 figures, 6 tables

  10. Risk Factors for Chronic Subdural Hematoma Recurrence Identified Using Quantitative Computed Tomography Analysis of Hematoma Volume and Density.

    Science.gov (United States)

    Stavrinou, Pantelis; Katsigiannis, Sotirios; Lee, Jong Hun; Hamisch, Christina; Krischek, Boris; Mpotsaris, Anastasios; Timmer, Marco; Goldbrunner, Roland

    2017-03-01

    Chronic subdural hematoma (CSDH), a common condition in elderly patients, presents a therapeutic challenge with recurrence rates of 33%. We aimed to identify specific prognostic factors for recurrence using quantitative analysis of hematoma volume and density. We retrospectively reviewed radiographic and clinical data of 227 CSDHs in 195 consecutive patients who underwent evacuation of the hematoma through a single burr hole, 2 burr holes, or a mini-craniotomy. To examine the relationship between hematoma recurrence and various clinical, radiologic, and surgical factors, we used quantitative image-based analysis to measure the hematoma and trapped air volumes and the hematoma densities. Recurrence of CSDH occurred in 35 patients (17.9%). Multivariate logistic regression analysis revealed that the percentage of hematoma drained and postoperative CSDH density were independent risk factors for recurrence. All 3 evacuation methods were equally effective in draining the hematoma (71.7% vs. 73.7% vs. 71.9%) without observable differences in postoperative air volume captured in the subdural space. Quantitative image analysis provided evidence that percentage of hematoma drained and postoperative CSDH density are independent prognostic factors for subdural hematoma recurrence. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. First experiences with model based iterative reconstructions influence on quantitative plaque volume and intensity measurements in coronary computed tomography angiography

    International Nuclear Information System (INIS)

    Precht, H.; Kitslaar, P.H.; Broersen, A.; Gerke, O.; Dijkstra, J.; Thygesen, J.; Egstrup, K.; Lambrechtsen, J.

    2017-01-01

    Purpose: Investigate the influence of adaptive statistical iterative reconstruction (ASIR) and the model-based IR (Veo) reconstruction algorithm in coronary computed tomography angiography (CCTA) images on quantitative measurements in coronary arteries for plaque volumes and intensities. Methods: Three patients had three independent dose reduced CCTA performed and reconstructed with 30% ASIR (CTDI vol at 6.7 mGy), 60% ASIR (CTDI vol 4.3 mGy) and Veo (CTDI vol at 1.9 mGy). Coronary plaque analysis was performed for each measured CCTA volumes, plaque burden and intensities. Results: Plaque volume and plaque burden show a decreasing tendency from ASIR to Veo as median volume for ASIR is 314 mm 3 and 337 mm 3 –252 mm 3 for Veo and plaque burden is 42% and 44% for ASIR to 39% for Veo. The lumen and vessel volume decrease slightly from 30% ASIR to 60% ASIR with 498 mm 3 –391 mm 3 for lumen volume and vessel volume from 939 mm 3 to 830 mm 3 . The intensities did not change overall between the different reconstructions for either lumen or plaque. Conclusion: We found a tendency of decreasing plaque volumes and plaque burden but no change in intensities with the use of low dose Veo CCTA (1.9 mGy) compared to dose reduced ASIR CCTA (6.7 mGy & 4.3 mGy), although more studies are warranted. - Highlights: • Veo decrease plaque volumes and plaque burden using low-dose CCTA. • Moving from ASIR 30%, ASIR 60% to Veo did not appear to influence the plaque intensities. • Studies including larger sample size are needed to investigate the effect on plaque.

  12. Generating quantitative models describing the sequence specificity of biological processes with the stabilized matrix method

    Directory of Open Access Journals (Sweden)

    Sette Alessandro

    2005-05-01

    Full Text Available Abstract Background Many processes in molecular biology involve the recognition of short sequences of nucleic-or amino acids, such as the binding of immunogenic peptides to major histocompatibility complex (MHC molecules. From experimental data, a model of the sequence specificity of these processes can be constructed, such as a sequence motif, a scoring matrix or an artificial neural network. The purpose of these models is two-fold. First, they can provide a summary of experimental results, allowing for a deeper understanding of the mechanisms involved in sequence recognition. Second, such models can be used to predict the experimental outcome for yet untested sequences. In the past we reported the development of a method to generate such models called the Stabilized Matrix Method (SMM. This method has been successfully applied to predicting peptide binding to MHC molecules, peptide transport by the transporter associated with antigen presentation (TAP and proteasomal cleavage of protein sequences. Results Herein we report the implementation of the SMM algorithm as a publicly available software package. Specific features determining the type of problems the method is most appropriate for are discussed. Advantageous features of the package are: (1 the output generated is easy to interpret, (2 input and output are both quantitative, (3 specific computational strategies to handle experimental noise are built in, (4 the algorithm is designed to effectively handle bounded experimental data, (5 experimental data from randomized peptide libraries and conventional peptides can easily be combined, and (6 it is possible to incorporate pair interactions between positions of a sequence. Conclusion Making the SMM method publicly available enables bioinformaticians and experimental biologists to easily access it, to compare its performance to other prediction methods, and to extend it to other applications.

  13. Mammographic quantitative image analysis and biologic image composition for breast lesion characterization and classification

    Energy Technology Data Exchange (ETDEWEB)

    Drukker, Karen, E-mail: kdrukker@uchicago.edu; Giger, Maryellen L.; Li, Hui [Department of Radiology, University of Chicago, Chicago, Illinois 60637 (United States); Duewer, Fred; Malkov, Serghei; Joe, Bonnie; Kerlikowske, Karla; Shepherd, John A. [Radiology Department, University of California, San Francisco, California 94143 (United States); Flowers, Chris I. [Department of Radiology, University of South Florida, Tampa, Florida 33612 (United States); Drukteinis, Jennifer S. [Department of Radiology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida 33612 (United States)

    2014-03-15

    Purpose: To investigate whether biologic image composition of mammographic lesions can improve upon existing mammographic quantitative image analysis (QIA) in estimating the probability of malignancy. Methods: The study population consisted of 45 breast lesions imaged with dual-energy mammography prior to breast biopsy with final diagnosis resulting in 10 invasive ductal carcinomas, 5 ductal carcinomain situ, 11 fibroadenomas, and 19 other benign diagnoses. Analysis was threefold: (1) The raw low-energy mammographic images were analyzed with an established in-house QIA method, “QIA alone,” (2) the three-compartment breast (3CB) composition measure—derived from the dual-energy mammography—of water, lipid, and protein thickness were assessed, “3CB alone”, and (3) information from QIA and 3CB was combined, “QIA + 3CB.” Analysis was initiated from radiologist-indicated lesion centers and was otherwise fully automated. Steps of the QIA and 3CB methods were lesion segmentation, characterization, and subsequent classification for malignancy in leave-one-case-out cross-validation. Performance assessment included box plots, Bland–Altman plots, and Receiver Operating Characteristic (ROC) analysis. Results: The area under the ROC curve (AUC) for distinguishing between benign and malignant lesions (invasive and DCIS) was 0.81 (standard error 0.07) for the “QIA alone” method, 0.72 (0.07) for “3CB alone” method, and 0.86 (0.04) for “QIA+3CB” combined. The difference in AUC was 0.043 between “QIA + 3CB” and “QIA alone” but failed to reach statistical significance (95% confidence interval [–0.17 to + 0.26]). Conclusions: In this pilot study analyzing the new 3CB imaging modality, knowledge of the composition of breast lesions and their periphery appeared additive in combination with existing mammographic QIA methods for the distinction between different benign and malignant lesion types.

  14. Development of a Univariate Membrane-Based Mid-Infrared Method for Protein Quantitation and Total Lipid Content Analysis of Biological Samples

    Directory of Open Access Journals (Sweden)

    Ivona Strug

    2014-01-01

    Full Text Available Biological samples present a range of complexities from homogeneous purified protein to multicomponent mixtures. Accurate qualification of such samples is paramount to downstream applications. We describe the development of an MIR spectroscopy-based analytical method offering simultaneous protein quantitation (0.25–5 mg/mL and analysis of total lipid or detergent species, as well as the identification of other biomolecules present in biological samples. The method utilizes a hydrophilic PTFE membrane engineered for presentation of aqueous samples in a dried format compatible with fast infrared analysis. Unlike classical quantification techniques, the reported method is amino acid sequence independent and thus applicable to complex samples of unknown composition. By comparison to existing platforms, this MIR-based method enables direct quantification using minimal sample volume (2 µL; it is well-suited where repeat access and limited sample size are critical parameters. Further, accurate results can be derived without specialized training or knowledge of IR spectroscopy. Overall, the simplified application and analysis system provides a more cost-effective alternative to high-throughput IR systems for research laboratories with minimal throughput demands. In summary, the MIR-based system provides a viable alternative to current protein quantitation methods; it also uniquely offers simultaneous qualification of other components, notably lipids and detergents.

  15. Occipital Lobe Gray Matter Volume in Male Patients with Chronic Schizophrenia: A Quantitative MRI Study

    Science.gov (United States)

    Onitsuka, Toshiaki; McCarley, Robert W.; Kuroki, Noriomi; Dickey, Chandlee C.; Kubicki, Marek; Demeo, Susan S.; Frumin, Melissa; Kikinis, Ron; Jolesz, Ferenc A.; Shenton, Martha E.

    2008-01-01

    Schizophrenia is characterized by deficits in cognition as well as visual perception. There have, however, been few magnetic resonance imaging (MRI) studies of the occipital lobe as an anatomically defined region of interest in schizophrenia. To examine whether or not patients with chronic schizophrenia show occipital lobe volume abnormalities, we measured gray matter volumes for both the primary visual area (PVA) and the visual association areas (VAA) using MRI based neuroanatomical landmarks and three-dimensional information. PVA and VAA gray matter volumes were measured using high-spatial resolution MRI in 25 male patients diagnosed with chronic schizophrenia and in 28 male normal controls. Chronic schizophrenia patients showed reduced bilateral VAA gray matter volume (11%), compared with normal controls, whereas patients showed no group difference in PVA gray matter volume. These results suggest that reduced bilateral VAA may be a neurobiological substrate of some of the deficits observed in early visual processing in schizophrenia. PMID:17350226

  16. X-ray cone beam microtomography for quantitative assessment of tracheal and pharyngeal volumes of Rhodnius prolixus

    International Nuclear Information System (INIS)

    Souza, Izabella Soares de

    2017-01-01

    In the past decade microcomputerized tomography imaging using synchrotron radiation has become a powerful technique to generate high resolution images of Rhodinus prolixus. Images of soft tissues (protocerebrum and muscles) and dense structures (pharynx, trachea and esophagus) of R. prolixus head have been obtained using synchrotron radiation microtomography in mono and polychromatic configuration, respectively. Advancements in conventional microtomography have increased the achievable resolution and contrast, making this relatively inexpensive and widely available technology potentially useful for studies of insect internal morphology. The main goal of this work was to provide a new set of high quality microtomographic images of R. prolixus achieved by means of a desktop X-ray microtomograph. It allows the three-dimensional visualization of important chitinized structures: pharynx and tracheae. Pharyngeal and tracheal volumes were quantitatively evaluated at different days (1, 4, 10, 15 and 20) after feeding. The results suggest that variation of average volumes could be attributed to insect hormone 20-hydroxy-ecdysone (20-OH-Ec) pulse at 11 days after feeding. Pharyngeal volumes decrease 3.80 times. On the other hand, tracheal volumes increase 1.78 times. Head total volume showed similar trends than trachea. (author)

  17. Application of LC–MS/MS for quantitative analysis of glucocorticoids and stimulants in biological fluids

    Directory of Open Access Journals (Sweden)

    Jamshed Haneef

    2013-10-01

    Full Text Available Liquid chromatography tandem mass chromatography (LC–MS/MS is an important hyphenated technique for quantitative analysis of drugs in biological fluids. Because of high sensitivity and selectivity, LC–MS/MS has been used for pharmacokinetic studies, metabolites identification in the plasma and urine. This manuscript gives comprehensive analytical review, focusing on chromatographic separation approaches (column packing materials, column length and mobile phase as well as different acquisition modes (SIM, MRM for quantitative analysis of glucocorticoids and stimulants. This review is not meant to be exhaustive but rather to provide a general overview for detection and confirmation of target drugs using LC–MS/MS and thus useful in the doping analysis, toxicological studies as well as in pharmaceutical analysis. Keywords: LC–MS/MS, Ionization techniques, Glucocorticoids, Stimulants, Hyphenated techniques, Biological fluid

  18. Gender, Math Confidence, and Grit: Relationships with Quantitative Skills and Performance in an Undergraduate Biology Course

    Science.gov (United States)

    Flanagan, K. M.; Einarson, J.

    2017-01-01

    In a world filled with big data, mathematical models, and statistics, the development of strong quantitative skills is becoming increasingly critical for modern biologists. Teachers in this field must understand how students acquire quantitative skills and explore barriers experienced by students when developing these skills. In this study, we…

  19. Technical Performance Capability of Fourier Transform Profilometry for Quantitative Waste Volume Determination under Hanford Waste Tank Condition

    International Nuclear Information System (INIS)

    Monts, D.L.; Jang, P.R.; Long, Z.; Norton, O.P.; Okhuysen, W.P.; Su, Y.; Waggoner, Ch.A.

    2009-01-01

    The Hanford Site is currently in the process of an extensive effort to empty and close its radioactive single-shell and double-shell waste storage tanks. Before this can be accomplished, it is necessary to know how much residual material is left in a given waste tank and the chemical makeup of the residue. The Institute for Clean Energy Technology (ICET) at Mississippi State University is currently developing a quantitative in-tank inspection system based on Fourier Transform Profilometry (FTP). FTP is a non-contact, 3-D shape measurement technique. By projecting a fringe pattern onto a target surface and observing its deformation due to surface irregularities from a different view angle, FTP is capable of determining the height (depth) distribution (and hence volume distribution) of the target surface, thus reproducing the profile of the target accurately under a wide variety of conditions. Hence FTP has the potential to be utilized for quantitative determination of residual wastes within Hanford waste tanks. We report the results of a technical feasibility study to document the accuracy and precision of quantitative volume determination using the Fourier transform profilometry technique under simulated Hanford waste tank conditions. (authors)

  20. LONGITUDINAL QUANTITATIVE EVALUATION OF PHOTORECEPTOR VOLUME FOLLOWING REPAIR OF MACULA-OFF RETINAL DETACHMENT.

    Science.gov (United States)

    Narala, Ramsudha; Scarinci, Fabio; Shaarawy, Amr; Simonett, Joseph M; Flaxel, Christina J; Fawzi, Amani A

    2016-08-01

    To quantify photoreceptor volume changes after successful surgical repair of macula-off retinal detachment and to correlate these volumetric changes to postoperative best-corrected visual acuity (BCVA). Retrospective study of 15 eyes of 15 patients with macula-off retinal detachment who underwent successful surgical repair. A minimum of 4 optical coherence tomography scans that straddled the foveal center was used to quantify the central photoreceptor volume (central 1 mm). Mean photoreceptor volume at the first postoperative visit was 0.451 mm, increasing to 0.523 mm at the final postoperative visit (P = 0.004). Mean BCVA improved from 1.13 ± 0.59 logarithm of the minimum angle of resolution units (∼20/270) preoperatively to 0.52 ± 0.42 logarithm of the minimum angle of resolution units (∼20/66) at the final postoperative visit (P = 0.001). Mean photoreceptor volume at either the initial or final visit demonstrated significant correlations with final postoperative BCVA (r = -0.670, P = 0.017 and r = -0.753, P = 0.005, respectively). Shorter time interval from diagnosis to surgery was significantly associated with greater mean final postoperative photoreceptor volume (r = -0.588, P = 0.021) and better mean final postoperative BCVA (r = 0.709, P = 0.003). We observed a significant increase in photoreceptor volume after successful retinal detachment repair; photoreceptor volume was positively associated with BCVA and time to surgery. Our series emphasizes the importance of prompt surgical repair and shows that photoreceptor recovery and volumetric improvement correlate significantly with BCVA.

  1. Temperature-dependent phase transitions in zeptoliter volumes of a complex biological membrane

    International Nuclear Information System (INIS)

    Nikiforov, Maxim P; Jesse, Stephen; Kalinin, Sergei V; Hohlbauch, Sophia; Proksch, Roger; King, William P; Voitchovsky, Kislon; Contera, Sonia Antoranz

    2011-01-01

    Phase transitions in purple membrane have been a topic of debate for the past two decades. In this work we present studies of a reversible transition of purple membrane in the 50-60 deg. C range in zeptoliter volumes under different heating regimes (global heating and local heating). The temperature of the reversible phase transition is 52 ± 5 deg. C for both local and global heating, supporting the hypothesis that this transition is mainly due to a structural rearrangement of bR molecules and trimers. To achieve high resolution measurements of temperature-dependent phase transitions, a new scanning probe microscopy-based method was developed. We believe that our new technique can be extended to other biological systems and can contribute to the understanding of inhomogeneous phase transitions in complex systems.

  2. Space Biology and Medicine. Volume 4; Health, Performance, and Safety of Space Crews

    Science.gov (United States)

    Dietlein, Lawrence F. (Editor); Pestov, Igor D. (Editor)

    2004-01-01

    Volume IV is devoted to examining the medical and associated organizational measures used to maintain the health of space crews and to support their performance before, during, and after space flight. These measures, collectively known as the medical flight support system, are important contributors to the safety and success of space flight. The contributions of space hardware and the spacecraft environment to flight safety and mission success are covered in previous volumes of the Space Biology and Medicine series. In Volume IV, we address means of improving the reliability of people who are required to function in the unfamiliar environment of space flight as well as the importance of those who support the crew. Please note that the extensive collaboration between Russian and American teams for this volume of work resulted in a timeframe of publication longer than originally anticipated. Therefore, new research or insights may have emerged since the authors composed their chapters and references. This volume includes a list of authors' names and addresses should readers seek specifics on new information. At least three groups of factors act to perturb human physiological homeostasis during space flight. All have significant influence on health, psychological, and emotional status, tolerance, and work capacity. The first and most important of these factors is weightlessness, the most specific and radical change in the ambient environment; it causes a variety of functional and structural changes in human physiology. The second group of factors precludes the constraints associated with living in the sealed, confined environment of spacecraft. Although these factors are not unique to space flight, the limitations they entail in terms of an uncomfortable environment can diminish the well-being and performance of crewmembers in space. The third group of factors includes the occupational and social factors associated with the difficult, critical nature of the

  3. The next generation of training for Arabidopsis researchers: bioinformatics and quantitative biology

    Science.gov (United States)

    It has been more than 50 years since Arabidopsis (Arabidopsis thaliana) was first introduced as a model organism to understand basic processes in plant biology. A well-organized scientific community has used this small reference plant species to make numerous fundamental plant biology discoveries (P...

  4. Stereological estimates of nuclear volume and other quantitative variables in supratentorial brain tumors. Practical technique and use in prognostic evaluation

    DEFF Research Database (Denmark)

    Sørensen, Flemming Brandt; Braendgaard, H; Chistiansen, A O

    1991-01-01

    The use of morphometry and modern stereology in malignancy grading of brain tumors is only poorly investigated. The aim of this study was to present these quantitative methods. A retrospective feasibility study of 46 patients with supratentorial brain tumors was carried out to demonstrate...... the practical technique. The continuous variables were correlated with the subjective, qualitative WHO classification of brain tumors, and the prognostic value of the parameters was assessed. Well differentiated astrocytomas (n = 14) had smaller estimates of the volume-weighted mean nuclear volume and mean...... nuclear profile area, than those of anaplastic astrocytomas (n = 13) (2p = 3.1.10(-3) and 2p = 4.8.10(-3), respectively). No differences were seen between the latter type of tumor and glioblastomas (n = 19). The nuclear index was of the same magnitude in all three tumor types, whereas the mitotic index...

  5. Biologic lung volume reduction in advanced upper lobe emphysema: phase 2 results.

    Science.gov (United States)

    Criner, Gerard J; Pinto-Plata, Victor; Strange, Charlie; Dransfield, Mark; Gotfried, Mark; Leeds, William; McLennan, Geoffrey; Refaely, Yael; Tewari, Sanjiv; Krasna, Mark; Celli, Bartolome

    2009-05-01

    Biologic lung volume reduction (BioLVR) is a new endobronchial treatment for advanced emphysema that reduces lung volume through tissue remodeling. Assess the safety and therapeutic dose of BioLVR hydrogel in upper lobe predominant emphysema. Open-labeled, multicenter phase 2 dose-ranging studies were performed with BioLVR hydrogel administered to eight subsegmental sites (four in each upper lobe) involving: (1) low-dose treatment (n = 28) with 10 ml per site (LD); and (2) high-dose treatment (n = 22) with 20 ml per site (HD). Safety was assessed by the incidence of serious medical complications. Efficacy was assessed by change from baseline in pulmonary function tests, dyspnea score, 6-minute walk distance, and health-related quality of life. After treatment there were no deaths and four serious treatment-related complications. A reduction in residual volume to TLC ratio at 12 weeks (primary efficacy outcome) was achieved with both LD (-6.4 +/- 9.3%; P = 0.002) and HD (-5.5 +/- 9.4%; P = 0.028) treatments. Improvements in pulmonary function in HD (6 mo: DeltaFEV(1) = +15.6%; P = 0.002; DeltaFVC = +9.1%; P = 0.034) were greater than in LD patients (6 mo: DeltaFEV(1) = +6.7%; P = 0.021; DeltaFVC = +5.1%; P = 0.139). LD- and HD-treated groups both demonstrated improved symptom scores and health-related quality of life. BioLVR improves physiology and functional outcomes up to 6 months with an acceptable safety profile in upper lobe predominant emphysema. Overall improvement was greater and responses more durable with 20 ml per site than 10 ml per site dosing. Clinical trial registered with www.clinicaltrials.gov (NCT 00435253 and NCT 00515164).

  6. Quantitative analysis of normal fetal medulla oblongata volume and flow by three-dimensional power Doppler ultrasound.

    Science.gov (United States)

    Shyu, Ing-Luen; Wang, Peng-Hui; Chen, Chih-Yao; Chen, Yi-Jen; Chang, Chia-Ming; Horng, Huann-Cheng; Yang, Ming-Jie; Yen, Ming-Shyen

    2016-06-01

    Assessment of the fetal medulla oblongata volume (MOV) and blood flow might be important in the evaluation of fetal brain growth. We used three-dimensional power Doppler ultrasound (3DPDUS) to assess the fetal MOV and blood flow index in normal gestation. The relationships between these parameters were further analyzed. We assessed the total volume and blood flow index of the fetal MO in normal pregnancies using a 3DPDUS (Voluson 730 Expert). The true sagittal plane over the fetal occipital area was measured by a 3D transabdominal probe to scan the fetal MO under the power Doppler mode. Then, we quantitatively assessed the total volume of the fetal MOV, mean gray area (MG), vascularization index (VI), and flow index (FI). A total of 106 fetuses, ranging from 19 weeks to 39 weeks of gestation, were involved in our study. The volume of the fetal MO was highly positively correlated with gestational age [correlation coefficient (r) = 0.686, p < 0.0001]. The MG was negatively correlated with gestational age [r = -0.544, p < 0.0001). VI and FI showed no significant correlation with gestational age (p = 0.123 and p = 0.219, respectively). 3DPDUS can be used to assess the fetal MOV and blood flow development quantitatively. Our study indicated that fetal MOV and blood flow correlated significantly with the advancement of gestational age. This information may serve as reference data for further studies of the fetal brain and blood flow under abnormal conditions. Copyright © 2016. Published by Elsevier B.V.

  7. The quantitative study of marked individuals in ecology, evolution and conservation biology: a foreword to the EURING 2003 Conference

    Directory of Open Access Journals (Sweden)

    Senar, J. C.

    2004-06-01

    were charged with selecting 4-7 talks on the topic of their session. Each session additionally included a plenary conference intended to summarise or to provide a general but synthetic flavour of the topic. As a novelty in EURING conferences, we asked session chairs to include at least one talk dealing with study species other than birds. This is the result of a heated but fruitful discussion at EURING 2000 in Point Reyes, and fits with the general aim to spread the capture-recapture methodology beyond zoological groups: although EURING as an organization, deals with birds, and conferences have traditionally focused on this group, the capture-recapture approach is becoming a standard way to address biologically relevant questions on populations and individuals (Schwarz, 2002, for any zoological group. This volume, contains several nice examples of taxa other than birds. As far as possible, we selected chairs so that each session was delineated with a good balance between the biological and the statistician emphasis. This balance has in fact characterised EURING conferences, which in addition to the workshop atmosphere always present, has lead to very fruitful exchanges. Session The quantitative study of marked individuals in ecology, evolution and conservation biology: a foreword to the EURING 2003 Conference which in addition to the workshop atmosphere always present, has lead to very fruitful exchanges. Session chairs were also asked to act as editors for the papers within their session. All the papers were hence subjected to peer review, as in any other issue of Animal Biodiversity and Conservation, and presentation of the paper in the Conference did not assure publication in the Proceedings. This has lead to an even higher quality of the papers presented at the Conference. Editors were additionally asked to write a short summary on their session. Given that these summaries also present the views of the Editors on the different topics presented, we have preferred

  8. Technical performance characterization of fourier transform profilometry for quantitative waste volume determination under Hanford waste tank conditions - 16281

    International Nuclear Information System (INIS)

    Monts, David L.; Jang, Ping-Rey; Long, Zhiling; Norton, Olin P.; Gresham, Lawrence L.; Su, Yi; Lindner, Jeffrey S.

    2009-01-01

    The Hanford Site in western Washington state is currently in the process of an extensive effort to empty and close its radioactive single-shell and double-shell waste storage tanks. Before this can be accomplished, it is necessary to know how much residual material is left in a given waste tank and the chemical makeup of the residue. The Institute for Clean Energy Technology (ICET) at Mississippi State University is currently developing an quantitative in-tank inspection system based on Fourier Transform Profilometry, FTP. FTP is a non-contact, 3-D shape measurement technique. By projecting a fringe pattern onto a target surface and observing its deformation due to surface irregularities from a different view angle, FTP is capable of determining the height (depth) distribution (and hence volume distribution) of the target surface, thus reproducing the profile of the target accurately under a wide variety of conditions. Hence FTP has the potential to be utilized for quantitative determination of residual wastes within Hanford waste tanks. We report the results of a technical feasibility study to document the accuracy and precision of quantitative volume determination using the Fourier transform profilometry technique under simulated Hanford waste tank conditions. We have initiated a technical feasibility assessment of the Fourier transform profilometry (FTP) technique for determining the volume of residual waste in Hanford radioactive waste tanks; preliminary results to date are presented in this paper. We find that we achieve FTP volume determinations with relatively small errors under conditions corresponding to the most challenging within a Hanford waste tank-viewing non-descript targets at a distance of 16.1 m (53 ft) and an angle of 62 deg.. We have determined that we can minimize measurement uncertainty by maximizing the camera-to-projector distance d, using an optical zoom of at least 5x, and ensuring that FTP images are only recorded after instrumental warm

  9. Fuzzy hidden Markov chains segmentation for volume determination and quantitation in PET

    Energy Technology Data Exchange (ETDEWEB)

    Hatt, M [INSERM U650, Laboratoire du Traitement de l' Information Medicale (LaTIM), CHU Morvan, Bat 2bis (I3S), 5 avenue Foch, Brest, 29609 (France); Lamare, F [INSERM U650, Laboratoire du Traitement de l' Information Medicale (LaTIM), CHU Morvan, Bat 2bis (I3S), 5 avenue Foch, Brest, 29609, (France); Boussion, N [INSERM U650, Laboratoire du Traitement de l' Information Medicale (LaTIM), CHU Morvan, Bat 2bis (I3S), 5 avenue Foch, Brest, 29609 (France); Turzo, A [INSERM U650, Laboratoire du Traitement de l' Information Medicale (LaTIM), CHU Morvan, Bat 2bis (I3S), 5 avenue Foch, Brest, 29609 (France); Collet, C [Ecole Nationale Superieure de Physique de Strasbourg (ENSPS), ULP, Strasbourg, F-67000 (France); Salzenstein, F [Institut d' Electronique du Solide et des Systemes (InESS), ULP, Strasbourg, F-67000 (France); Roux, C [INSERM U650, Laboratoire du Traitement de l' Information Medicale (LaTIM), CHU Morvan, Bat 2bis (I3S), 5 avenue Foch, Brest, 29609 (France); Jarritt, P [Medical Physics Agency, Royal Victoria Hospital, Belfast (United Kingdom); Carson, K [Medical Physics Agency, Royal Victoria Hospital, Belfast (United Kingdom); Rest, C Cheze-Le [INSERM U650, Laboratoire du Traitement de l' Information Medicale (LaTIM), CHU Morvan, Bat 2bis (I3S), 5 avenue Foch, Brest, 29609 (France); Visvikis, D [INSERM U650, Laboratoire du Traitement de l' Information Medicale (LaTIM), CHU Morvan, Bat 2bis (I3S), 5 avenue Foch, Brest, 29609 (France)

    2007-07-21

    Accurate volume of interest (VOI) estimation in PET is crucial in different oncology applications such as response to therapy evaluation and radiotherapy treatment planning. The objective of our study was to evaluate the performance of the proposed algorithm for automatic lesion volume delineation; namely the fuzzy hidden Markov chains (FHMC), with that of current state of the art in clinical practice threshold based techniques. As the classical hidden Markov chain (HMC) algorithm, FHMC takes into account noise, voxel intensity and spatial correlation, in order to classify a voxel as background or functional VOI. However the novelty of the fuzzy model consists of the inclusion of an estimation of imprecision, which should subsequently lead to a better modelling of the 'fuzzy' nature of the object of interest boundaries in emission tomography data. The performance of the algorithms has been assessed on both simulated and acquired datasets of the IEC phantom, covering a large range of spherical lesion sizes (from 10 to 37 mm), contrast ratios (4:1 and 8:1) and image noise levels. Both lesion activity recovery and VOI determination tasks were assessed in reconstructed images using two different voxel sizes (8 mm{sup 3} and 64 mm{sup 3}). In order to account for both the functional volume location and its size, the concept of % classification errors was introduced in the evaluation of volume segmentation using the simulated datasets. Results reveal that FHMC performs substantially better than the threshold based methodology for functional volume determination or activity concentration recovery considering a contrast ratio of 4:1 and lesion sizes of <28 mm. Furthermore differences between classification and volume estimation errors evaluated were smaller for the segmented volumes provided by the FHMC algorithm. Finally, the performance of the automatic algorithms was less susceptible to image noise levels in comparison to the threshold based techniques. The

  10. Quantitation of mandibular ramus volume as a source of bone grafting.

    Science.gov (United States)

    Verdugo, Fernando; Simonian, Krikor; Smith McDonald, Roberto; Nowzari, Hessam

    2009-10-01

    When alveolar atrophy impairs dental implant placement, ridge augmentation using mandibular ramus graft may be considered. In live patients, however, an accurate calculation of the amount of bone that can be safely harvested from the ramus has not been reported. The use of a software program to perform these calculations can aid in preventing surgical complications. The aim of the present study was to intra-surgically quantify the volume of the ramus bone graft that can be safely harvested in live patients, and compare it to presurgical computerized tomographic calculations. The AutoCAD software program quantified ramus bone graft in 40 consecutive patients from computerized tomographies. Direct intra-surgical measurements were recorded thereafter and compared to software data (n = 10). In these 10 patients, the bone volume was also measured at the recipient sites 6 months post-sinus augmentation. The mandibular second and third molar areas provided the thickest cortical graft averaging 2.8 +/- 0.6 mm. The thinnest bone was immediately posterior to the third molar (1.9 +/- 0.3 mm). The volume of ramus bone graft measured by AutoCAD averaged 0.8 mL (standard deviation [SD] 0.2 mL, range: 0.4-1.2 mL). The volume of bone graft measured intra-surgically averaged 2.5 mL (SD 0.4 mL, range: 1.8-3.0 mL). The difference between the two measurement methods was significant (p AutoCAD software program did not overestimate the volume of bone that can be safely harvested from the mandibular ramus.

  11. Quantitative, high-resolution proteomics for data-driven systems biology

    DEFF Research Database (Denmark)

    Cox, J.; Mann, M.

    2011-01-01

    Systems biology requires comprehensive data at all molecular levels. Mass spectrometry (MS)-based proteomics has emerged as a powerful and universal method for the global measurement of proteins. In the most widespread format, it uses liquid chromatography (LC) coupled to high-resolution tandem...... primary structure of proteins including posttranslational modifications, to localize proteins to organelles, and to determine protein interactions. Here, we describe the principles of analysis and the areas of biology where proteomics can make unique contributions. The large-scale nature of proteomics...... data and its high accuracy pose special opportunities as well as challenges in systems biology that have been largely untapped so far....

  12. Calculus, Biology and Medicine: A Case Study in Quantitative Literacy for Science Students

    Directory of Open Access Journals (Sweden)

    Kim Rheinlander

    2011-01-01

    Full Text Available This paper describes a course designed to enhance the numeracy of biology and pre-medical students. The course introduces students with the background of one semester of calculus to systems of nonlinear ordinary differential equations as they appear in the mathematical biology literature. Evaluation of the course showed increased enjoyment and confidence in doing mathematics, and an increased appreciation of the utility of mathematics to science. Students who complete this course are better able to read the research literature in mathematical biology and carry out research problems of their own.

  13. WE-B-304-02: Treatment Planning Evaluation and Optimization Should Be Biologically and Not Dose/volume Based

    International Nuclear Information System (INIS)

    Deasy, J.

    2015-01-01

    The ultimate goal of radiotherapy treatment planning is to find a treatment that will yield a high tumor control probability (TCP) with an acceptable normal tissue complication probability (NTCP). Yet most treatment planning today is not based upon optimization of TCPs and NTCPs, but rather upon meeting physical dose and volume constraints defined by the planner. It has been suggested that treatment planning evaluation and optimization would be more effective if they were biologically and not dose/volume based, and this is the claim debated in this month’s Point/Counterpoint. After a brief overview of biologically and DVH based treatment planning by the Moderator Colin Orton, Joseph Deasy (for biological planning) and Charles Mayo (against biological planning) will begin the debate. Some of the arguments in support of biological planning include: this will result in more effective dose distributions for many patients DVH-based measures of plan quality are known to have little predictive value there is little evidence that either D95 or D98 of the PTV is a good predictor of tumor control sufficient validated outcome prediction models are now becoming available and should be used to drive planning and optimization Some of the arguments against biological planning include: several decades of experience with DVH-based planning should not be discarded we do not know enough about the reliability and errors associated with biological models the radiotherapy community in general has little direct experience with side by side comparisons of DVH vs biological metrics and outcomes it is unlikely that a clinician would accept extremely cold regions in a CTV or hot regions in a PTV, despite having acceptable TCP values Learning Objectives: To understand dose/volume based treatment planning and its potential limitations To understand biological metrics such as EUD, TCP, and NTCP To understand biologically based treatment planning and its potential limitations

  14. Quantitative analysis of macular retinal thickness and macular volume in diabetic retinopathy

    Directory of Open Access Journals (Sweden)

    Ying Zhao

    2017-12-01

    Full Text Available AIM: To evaluate and characterize the macular thickness and macular volume in patients of different stages of diabetic retinopathy with special-domain optical coherence tomography(SD-OCT. METHODS: Totally 40 patients(78 eyeswith diabetic retinopathy were recruited in the study from January 2016 to January 2017 in our hospital. According to the international clinical classification of diabetic retinopathy, 20 cases(40 eyeswere categorized as non-proliferative diabetic retinopathy(NPDRgroup and 20 cases proliferative diabetic retinopathy(PDRgroup(38 eyes. All subjects were examined and analyzed with Early Treatment Diabetic Retinopathy Study(ETDRSsubfields, which were embedded in HS(Haag-Streitwith diameter of 1, 3 and 6mm.The changes of retinal thickness and volume of the macular center were measured. RESULTS: The thickness of macular foveolar in NPDR group and PDR group were 252.57±31.36μm, 362.47±20.81μm. The retinal thickness of inner superior subfield(ISMand inner nasal subfield(INMwere the thickest; that of inner inferior subfield(IIMwas next to ISM and INM, and that of inner temporal subfield was the thinnest. Of the outer subfields, the retinal thickness of outer superior subfield(OSMwas the thickest; that of outer nasal subfield(ONMwas next to OSM, and that of outer temporal subfield(OTMand outer inferior subfield(OIMwas the thinnest. The value of macular central concave thickness and retinal thickness in each quadrant of the NPDR group were less than those of the PDR group, the difference was statistically significant(P3, 0.28±0.16mm3, the upper and nasal sides of the middle part of the partition were the largest, the inferior and the temporal side were the smallest. The nasal side of the outer loop was the largest, the upper was the second, the temporal side and the inferior were the smallest. The volume of macular central fovea and the retinal volume in each quadrant of the NPDR group were smaller than those of the PDR group, the

  15. Quantitative gated SPECT: the effect of reconstruction filter on calculated left ventricular ejection fractions and volumes

    International Nuclear Information System (INIS)

    Wright, Graham A.; McDade, Mark; Martin, William; Hutton, William

    2002-01-01

    Gated SPECT (GSPECT) offers the possibility of obtaining additional functional information from perfusion studies, including calculation of left ventricular ejection fraction (LVEF). The calculation of LVEF relies upon the identification of the endocardial surface, which will be affected by the spatial resolution and statistical noise in the reconstructed images. The aim of this study was to compare LVEFs and ventricular volumes calculated from GSPECT using six reconstruction filters. GSPECT and radionuclide ventriculography (RNVG) were performed on 40 patients; filtered back projection was used to reconstruct the datasets with each filter. LVEFs and volumes were calculated using the Cedars-Sinai QGS package. The correlation coefficient between RNVG and GSPECT ranged from 0.81 to 0.86 with higher correlations for smoother filters. The narrowest prediction interval was 11±2%. There was a trend towards higher LVEF values with smoother filters, the ramp filter yielding LVEFs 2.55±3.10% (p<0.001) lower than the Hann filter. There was an overall fall in ventricular volumes with smoother filters with a mean difference of 13.98±10.15 ml (p<0.001) in EDV between the Butterworth-0.5 and Butterworth-0.3 filters. In conclusion, smoother reconstruction filters lead to lower volumes and higher ejection fractions with the QGS algorithm, with the Butterworth-0.4 filter giving the highest correlation with LVEFs from RNVG. Even if the optimal filter is chosen the uncertainty in the measured ejection fractions is still too great to be clinically acceptable. (author)

  16. Quantitative analysis of the corpus callosum in children with cerebral palsy and developmental delay: correlation with cerebral white matter volume

    International Nuclear Information System (INIS)

    Panigrahy, Ashok; Barnes, Patrick D.; Robertson, Robert L.; Sleeper, Lynn A.; Sayre, James W.

    2005-01-01

    This study was conducted to quantitatively correlate the thickness of the corpus callosum with the volume of cerebral white matter in children with cerebral palsy and developmental delay. Material and methods: A clinical database of 70 children with cerebral palsy and developmental delay was established with children between the ages of 1 and 5 years. These children also demonstrated abnormal periventricular T2 hyperintensities associated with and without ventriculomegaly. Mid-sagittal T1-weighted images were used to measure the thickness (genu, mid-body, and splenium) and length of the corpus callosum. Volumes of interest were digitized based on gray-scale densities to define the hemispheric cerebral white matter on axial T2-weighted and FLAIR images. The thickness of the mid-body of the corpus callosum was correlated with cerebral white matter volume. Subgroup analysis was also performed to examine the relationship of this correlation with both gestational age and neuromotor outcome. Statistical analysis was performed using analysis of variance and Pearson correlation coefficients. There was a positive correlation between the thickness of the mid-body of the corpus callosum and the volume of cerebral white matter across all children studied (R=0.665, P=0.0001). This correlation was not dependent on gestational age. The thickness of the mid-body of the corpus callosum was decreased in the spastic diplegia group compared to the two other groups (hypotonia and developmental delay only; P<0.0001). Within each neuromotor subgroup, there was a positive correlation between thickness of the mid-body of the corpus callosum and volume of the cerebral white matter. (orig.)

  17. Quantitative analysis of the corpus callosum in children with cerebral palsy and developmental delay: correlation with cerebral white matter volume

    Energy Technology Data Exchange (ETDEWEB)

    Panigrahy, Ashok [Childrens Hospital Los Angeles, Department of Radiology, Los Angeles, CA (United States); Barnes, Patrick D. [Stanford University Medical Center, Department of Radiology, Lucile Salter Packard Children' s Hospital, Palo Alto, CA (United States); Robertson, Robert L. [Children' s Hospital Boston, Department of Radiology, Boston, MA (United States); Sleeper, Lynn A. [New England Research Institute, Watertown, MA (United States); Sayre, James W. [UCLA Medical Center, Departments of Radiology and Biostatistics, Los Angeles, CA (United States)

    2005-12-01

    This study was conducted to quantitatively correlate the thickness of the corpus callosum with the volume of cerebral white matter in children with cerebral palsy and developmental delay. Material and methods: A clinical database of 70 children with cerebral palsy and developmental delay was established with children between the ages of 1 and 5 years. These children also demonstrated abnormal periventricular T2 hyperintensities associated with and without ventriculomegaly. Mid-sagittal T1-weighted images were used to measure the thickness (genu, mid-body, and splenium) and length of the corpus callosum. Volumes of interest were digitized based on gray-scale densities to define the hemispheric cerebral white matter on axial T2-weighted and FLAIR images. The thickness of the mid-body of the corpus callosum was correlated with cerebral white matter volume. Subgroup analysis was also performed to examine the relationship of this correlation with both gestational age and neuromotor outcome. Statistical analysis was performed using analysis of variance and Pearson correlation coefficients. There was a positive correlation between the thickness of the mid-body of the corpus callosum and the volume of cerebral white matter across all children studied (R=0.665, P=0.0001). This correlation was not dependent on gestational age. The thickness of the mid-body of the corpus callosum was decreased in the spastic diplegia group compared to the two other groups (hypotonia and developmental delay only; P<0.0001). Within each neuromotor subgroup, there was a positive correlation between thickness of the mid-body of the corpus callosum and volume of the cerebral white matter. (orig.)

  18. Novel Uses of In Vitro Data to Develop Quantitative Biological Activity Relationship Models for in Vivo Carcinogenicity Prediction.

    Science.gov (United States)

    Pradeep, Prachi; Povinelli, Richard J; Merrill, Stephen J; Bozdag, Serdar; Sem, Daniel S

    2015-04-01

    The availability of large in vitro datasets enables better insight into the mode of action of chemicals and better identification of potential mechanism(s) of toxicity. Several studies have shown that not all in vitro assays can contribute as equal predictors of in vivo carcinogenicity for development of hybrid Quantitative Structure Activity Relationship (QSAR) models. We propose two novel approaches for the use of mechanistically relevant in vitro assay data in the identification of relevant biological descriptors and development of Quantitative Biological Activity Relationship (QBAR) models for carcinogenicity prediction. We demonstrate that in vitro assay data can be used to develop QBAR models for in vivo carcinogenicity prediction via two case studies corroborated with firm scientific rationale. The case studies demonstrate the similarities between QBAR and QSAR modeling in: (i) the selection of relevant descriptors to be used in the machine learning algorithm, and (ii) the development of a computational model that maps chemical or biological descriptors to a toxic endpoint. The results of both the case studies show: (i) improved accuracy and sensitivity which is especially desirable under regulatory requirements, and (ii) overall adherence with the OECD/REACH guidelines. Such mechanism based models can be used along with QSAR models for prediction of mechanistically complex toxic endpoints. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Explicit tracking of uncertainty increases the power of quantitative rule-of-thumb reasoning in cell biology.

    Science.gov (United States)

    Johnston, Iain G; Rickett, Benjamin C; Jones, Nick S

    2014-12-02

    Back-of-the-envelope or rule-of-thumb calculations involving rough estimates of quantities play a central scientific role in developing intuition about the structure and behavior of physical systems, for example in so-called Fermi problems in the physical sciences. Such calculations can be used to powerfully and quantitatively reason about biological systems, particularly at the interface between physics and biology. However, substantial uncertainties are often associated with values in cell biology, and performing calculations without taking this uncertainty into account may limit the extent to which results can be interpreted for a given problem. We present a means to facilitate such calculations where uncertainties are explicitly tracked through the line of reasoning, and introduce a probabilistic calculator called CALADIS, a free web tool, designed to perform this tracking. This approach allows users to perform more statistically robust calculations in cell biology despite having uncertain values, and to identify which quantities need to be measured more precisely to make confident statements, facilitating efficient experimental design. We illustrate the use of our tool for tracking uncertainty in several example biological calculations, showing that the results yield powerful and interpretable statistics on the quantities of interest. We also demonstrate that the outcomes of calculations may differ from point estimates when uncertainty is accurately tracked. An integral link between CALADIS and the BioNumbers repository of biological quantities further facilitates the straightforward location, selection, and use of a wealth of experimental data in cell biological calculations. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  20. A biology-based approach for quantitative structure-activity relationships (QSARs) in ecotoxicity.

    NARCIS (Netherlands)

    Jager, T.; Kooijman, S.A.L.M.

    2009-01-01

    Quantitative structure-activity relationships (QSARs) for ecotoxicity can be used to fill data gaps and limit toxicity testing on animals. QSAR development may additionally reveal mechanistic information based on observed patterns in the data. However, the use of descriptive summary statistics for

  1. Quantitative terahertz time-domain spectroscopy and analysis in chemistry and biology

    DEFF Research Database (Denmark)

    Jepsen, Peter Uhd

    2005-01-01

    I will describe how Terahertz Time-Domain Spectroscopy (THz-TDS) can be used for quantitative, broadband spectroscopy in the far-infrared spectral region. Thz-TDS is sensitive to long-range, non-covalent interactions in the condensed phase, for instance intermolecular hydrogen bonding in molecula...

  2. Quantitative Evaluation of Biologic Therapy Options for Psoriasis: A Systematic Review and Network Meta-Analysis.

    Science.gov (United States)

    Jabbar-Lopez, Zarif K; Yiu, Zenas Z N; Ward, Victoria; Exton, Lesley S; Mohd Mustapa, M Firouz; Samarasekera, Eleanor; Burden, A David; Murphy, Ruth; Owen, Caroline M; Parslew, Richard; Venning, Vanessa; Warren, Richard B; Smith, Catherine H

    2017-08-01

    Multiple biologic treatments are licensed for psoriasis. The lack of head-to-head randomized controlled trials makes choosing between them difficult for patients, clinicians, and guideline developers. To establish their relative efficacy and tolerability, we searched MEDLINE, PubMed, Embase, and Cochrane for randomized controlled trials of licensed biologic treatments for skin psoriasis. We performed a network meta-analysis to identify direct and indirect evidence comparing biologics with one another, methotrexate, or placebo. We combined this with hierarchical cluster analysis to consider multiple outcomes related to efficacy and tolerability in combination for each treatment. Study quality, heterogeneity, and inconsistency were evaluated. Direct comparisons from 41 randomized controlled trials (20,561 participants) were included. All included biologics were efficacious compared with placebo or methotrexate at 3-4 months. Overall, cluster analysis showed adalimumab, secukinumab, and ustekinumab were comparable in terms of high efficacy and tolerability. Ixekizumab and infliximab were differentiated by very high efficacy but poorer tolerability. The lack of longer term controlled data limited our analysis to short-term outcomes. Trial performance may not equate to real-world performance, and so results need to be considered alongside real-world, long-term safety and effectiveness data. These data suggest that it is possible to discriminate between biologics to inform clinical practice and decision making (PROSPERO 2015:CRD42015017538). Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  3. Use of 5-(4-dimethylaminobenzylidene)rhodanine in quantitating silver grains eluted from autoradiograms of biological material

    International Nuclear Information System (INIS)

    Ludlow, J.W.; Guikema, J.A.; Consigli, R.A.

    1986-01-01

    5-(4-Dimethylaminobenzylidene)rhodanine, a silver-specific dye, was used in a colorimetric assay to quantitate the autoradiographic deposition of silver onto X-ray film after exposure to sodium dodecyl sulfate-polyacrylamide gels of radiolabeled biological material. Silver grains were eluted from autoradiograms with 5 N potassium hydroxide, dissolved in nitric acid, and neutralized with 1 M Trizma Base. The concentration of silver was measured spectrophotometrically owing to the chelation properties of the dye. After corrections for background exposure were made, the silver contents of excised bands were then determined by comparison to a standard curve generated with silver nitrate. We have used this silver assay to quantitate the relative amount of each polypeptide band comprising the polyomavirus structural protein VP2 doublet. The method reported here has proven useful when densitometry is inconvenient (i.e., short distance between bands, irregular shape of bands, very faint bands) in addition to being inexpensive and simple to perform

  4. Measurement issues associated with quantitative molecular biology analysis of complex food matrices for the detection of food fraud.

    Science.gov (United States)

    Burns, Malcolm; Wiseman, Gordon; Knight, Angus; Bramley, Peter; Foster, Lucy; Rollinson, Sophie; Damant, Andrew; Primrose, Sandy

    2016-01-07

    Following a report on a significant amount of horse DNA being detected in a beef burger product on sale to the public at a UK supermarket in early 2013, the Elliott report was published in 2014 and contained a list of recommendations for helping ensure food integrity. One of the recommendations included improving laboratory testing capacity and capability to ensure a harmonised approach for testing for food authenticity. Molecular biologists have developed exquisitely sensitive methods based on the polymerase chain reaction (PCR) or mass spectrometry for detecting the presence of particular nucleic acid or peptide/protein sequences. These methods have been shown to be specific and sensitive in terms of lower limits of applicability, but they are largely qualitative in nature. Historically, the conversion of these qualitative techniques into reliable quantitative methods has been beset with problems even when used on relatively simple sample matrices. When the methods are applied to complex sample matrices, as found in many foods, the problems are magnified resulting in a high measurement uncertainty associated with the result which may mean that the assay is not fit for purpose. However, recent advances in the technology and the understanding of molecular biology approaches have further given rise to the re-assessment of these methods for their quantitative potential. This review focuses on important issues for consideration when validating a molecular biology assay and the various factors that can impact on the measurement uncertainty of a result associated with molecular biology approaches used in detection of food fraud, with a particular focus on quantitative PCR-based and proteomics assays.

  5. Single x-ray absorptiometry method for the quantitative mammographic measure of fibroglandular tissue volume

    International Nuclear Information System (INIS)

    Malkov, Serghei; Wang, Jeff; Kerlikowske, Karla; Cummings, Steven R.; Shepherd, John A.

    2009-01-01

    Purpose: This study describes the design and characteristics of a highly accurate, precise, and automated single-energy method to quantify percent fibroglandular tissue volume (%FGV) and fibroglandular tissue volume (FGV) using digital screening mammography. Methods: The method uses a breast tissue-equivalent phantom in the unused portion of the mammogram as a reference to estimate breast composition. The phantom is used to calculate breast thickness and composition for each image regardless of x-ray technique or the presence of paddle tilt. The phantom adheres to the top of the mammographic compression paddle and stays in place for both craniocaudal and mediolateral oblique screening views. We describe the automated method to identify the phantom and paddle orientation with a three-dimensional reconstruction least-squares technique. A series of test phantoms, with a breast thickness range of 0.5-8 cm and a %FGV of 0%-100%, were made to test the accuracy and precision of the technique. Results: Using test phantoms, the estimated repeatability standard deviation equaled 2%, with a ±2% accuracy for the entire thickness and density ranges. Without correction, paddle tilt was found to create large errors in the measured density values of up to 7%/mm difference from actual breast thickness. This new density measurement is stable over time, with no significant drifts in calibration noted during a four-month period. Comparisons of %FGV to mammographic percent density and left to right breast %FGV were highly correlated (r=0.83 and 0.94, respectively). Conclusions: An automated method for quantifying fibroglandular tissue volume has been developed. It exhibited good accuracy and precision for a broad range of breast thicknesses, paddle tilt angles, and %FGV values. Clinical testing showed high correlation to mammographic density and between left and right breasts.

  6. Quantitative detection of glucose level based on radiofrequency patch biosensor combined with volume-fixed structures.

    Science.gov (United States)

    Qiang, Tian; Wang, Cong; Kim, Nam-Young

    2017-12-15

    A concept for characterizing a radiofrequency (RF) patch biosensor combined with volume-fixed structures is presented for timely monitoring of an individual's glucose levels based on frequency variation. Two types of patch biosensors-separately integrated with a backside slot (0.53μL) and a front-side tank (0.70μL) structure-were developed to achieve precise and efficient detection while excluding the effects of interference due to the liquidity, shape, and thickness of the tested glucose sample. A glucose test analyte at different concentrations (50-600mg/dL) was dropped into the volume-fixed structures. It fully interacted with the RF patch electromagnetic field, effectively and sensitively changing the resonance frequency and magnitude of the reflection coefficient. Measurement results based on the resonance frequency showed high sensitivity up to 1.13MHz and 1.97MHz per mg/dL, and low detection limits of 26.54mg/dL and 15.22mg/dL, for the two types of patch biosensors, respectively, as well as a short response time of less than 1s. Excellent reusability of the proposed biosensors was verified through three sets of measurements for each individual glucose sample. Regression analysis revealed a good linear correlation between glucose concentrations and the resonance frequency shift. Moreover, to facilitate a multi-parameter-sensitive detection of glucose, the magnitude of the reflection coefficient was also tested, and it showed a good linear correlation with the glucose concentration. Thus, the proposed approach can be adopted for distinguishing glucose solution levels, and it is a potential candidate for early-stage detection of glucose levels in diabetes patients. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Development of capillary electrophoresis methods for quantitative determination of taurine in vehicle system and biological media.

    Science.gov (United States)

    da Silva, Dayse L P; Rüttinger, Hans H; Mrestani, Yahia; Baum, Walter F; Neubert, Reinhard H H

    2006-06-01

    CE methods have been developed for the determination of taurine in pharmaceutical formulation (microemulsion) and in biological media such as sweat. The CE system with end-column pulsed amperometric detection has been found to be an interesting method in comparison with UV and fluorescence detection for its simplicity and rapidity. A gold-disk electrode of 100 mm diameter was used as the working electrode. The effects of a field decoupler at the end of the capillary, separation voltage, injection and pressure times were investigated. A detection limit of 4 x 10(-5) mol/L was reached using integrated pulsed amperometric detection, a method successfully applied to taurine analysis of the biological samples such as sweat. For taurine analysis of oil-in-water microemulsion, fluorescence detector was the favored method, the detection limit of which was 4 x 10(-11) mol/L.

  8. Preparation of Biological Samples Containing Metoprolol and Bisoprolol for Applying Methods for Quantitative Analysis

    OpenAIRE

    Corina Mahu Ştefania; Monica Hăncianu; Luminiţa Agoroaei; Anda Cristina Coman Băbuşanu; Elena Butnaru

    2015-01-01

    Arterial hypertension is a complex disease with many serious complications, representing a leading cause of mortality. Selective beta-blockers such as metoprolol and bisoprolol are frequently used in the management of hypertension. Numerous analytical methods have been developed for the determination of these substances in biological fluids, such as liquid chromatography coupled with mass spectrometry, gas chromatography coupled with mass spectrometry, high performance liquid chromatography. ...

  9. Quantitative determination of nitrogen biological fixation by the N-15 isotopic method

    International Nuclear Information System (INIS)

    Basantes, Emilio; Trivelin, Paulo; Mui Tsai, Siu

    1993-01-01

    In order to quantify the biological nitrogen fixation (BNF) and to evaluate the mycorrhiza effect in the BNF, an experiment was carried on by applying 1 5 N -ammonium sulphate and mycorrhiza fungi to the soil. The treatments included legumes: mucuna negra(Stizolobium atterrinum Piper et Tracv) and caupi (Vigna unguiculoata L. Walp). Two control plants: non nodulating soybean (Glycine max L.Merril) and rice (Oryza sativa), were used for measuring the fixed N in the legumes by isotope dilution method. Both legumes and control plants assimmilated the same ammounts of nitrogen from the soil and fertilizer. The greater N content in the legumnes was determined as coming from the fixed nitrogen. Rice and non nodulating soybean showed to be good controls for measuring biological nitrogen fixation using isotopic dilution method. The values of fixed nitrogen for legumes calculated using rice as control plant were slightly greater than those with non nodulating soybean, nevertheless there were no significant statistical differences between the values. The mucuna fixed more N than caupi in both mycorrhiza treatments (76.7, 66.6 and 56. 7 per cent of N fixed, respectively). The mycorrhiza increased dry matter yield (13.84 per cent), accumulation of N in the plant(14.85 per cent N) and the biological N fixation (16.06 per cent N-fixed) in caupi

  10. Assessment of in vivo MR imaging compared to physical sections in vitro-A quantitative study of brain volumes using stereology

    DEFF Research Database (Denmark)

    Jelsing, Jacob; Rostrup, Egill; Markenroth, Karin

    2005-01-01

    The object of the present study was to compare stereological estimates of brain volumes obtained in vivo by magnetic resonance imaging (MRI) to corresponding volumes from physical sections in vitro. Brains of ten domestic pigs were imaged using a 3-T scanner. The volumes of different brain....... However, although intraobserver difference of MRI estimates was acceptable, the interobserver difference was not. A statistical highly significant difference of 11-41% was observed between observers for volume estimates of all compartments considered. The study demonstrates that quantitative MRI...

  11. Active auxin uptake by zucchini membrane vesicles: quantitation using ESR volume and delta pH determinations

    International Nuclear Information System (INIS)

    Lomax, T.L.; Mehlhorn, R.J.; Briggs, W.R.

    1985-01-01

    Closed and pH-tight membrane vesicles prepared from hypocotyls of 5-day-old dark-grown seedlings of Cucurbita pepo accumulate the plant growth hormone indole-3-acetic acid along an imposed proton gradient (pH low outside, high inside). The use of electron paramagnetic spin probes permitted quantitation both of apparent vesicle volume and magnitude of the pH gradient. Under the experimental conditions used, hormone accumulation was at minimum 20-fold, a value 4 times larger than what one would predict if accumulation reflected only diffusional equilibrium at the measured pH gradient. It is concluded that hormone uptake is an active process, with each protonated molecule of hormone accompanied by an additional proton. Experiments with ionophores confirm that it is the pH gradient itself which drives the uptake

  12. Stereological estimation of nuclear volume and other quantitative histopathological parameters in the prognostic evaluation of supraglottic laryngeal squamous cell carcinoma

    DEFF Research Database (Denmark)

    Sørensen, Flemming Brandt; Bennedbaek, O; Pilgaard, J

    1989-01-01

    The aim of this study was to investigate various approaches to the grading of malignancy in pre-treatment biopsies from patients with supraglottic laryngeal squamous cell carcinoma. The prospects of objective malignancy grading based on stereological estimation of the volume-weighted mean nuclear...... observers of the latter was poor in the material which consisted of 35 biopsy specimens. Unbiased estimates of nuclear Vv were on the average 385 microns3 (CV = 0.44), with more than 90% of the associated variance attributable to differences in nuclear Vv among individual lesions. Nuclear Vv was positively....... None of the investigated categorical and quantitative parameters (cutoff points = means) reached the level of significance with respect to prognostic value. However, nuclear Vv showed the best information concerning survival (2p = 0.08), and this estimator offers optimal features for objective...

  13. Quantitation of regional cerebral blood flow corrected for partial volume effect using O-15 water and PET

    DEFF Research Database (Denmark)

    IIda, H.; Law, I.; Pakkenberg, B.

    2000-01-01

    Limited spatial resolution of positron emission tomography (PET) can cause significant underestimation in the observed regional radioactivity concentration (so-called partial volume effect or PVE) resulting in systematic errors in estimating quantitative physiologic parameters. The authors have...... formulated four mathematical models that describe the dynamic behavior of a freely diffusible tracer (H215O) in a region of interest (ROI) incorporating estimates of regional tissue flow that are independent of PVE. The current study was intended to evaluate the feasibility of these models and to establish...... a methodology to accurately quantify regional cerebral blood flow (CBF) corrected for PVE in cortical gray matter regions. Five monkeys were studied with PET after IV H2(15)O two times (n = 3) or three times (n = 2) in a row. Two ROIs were drawn on structural magnetic resonance imaging (MRI) scans and projected...

  14. Epicardial fat volume and aortic stiffness in healthy individuals. A quantitative cardiac magnetic resonance study

    Energy Technology Data Exchange (ETDEWEB)

    Homsi, R.; Thomas, D.; Meier-Schroers, M.; Dabir, D.; Kuetting, D.; Luetkens, J.A.; Marx, C.; Schild, H.H. [Bonn University Hospital (Germany). Radiology; Gieseke, J. [Philips Healthcare, Hamburg (Germany); Sprinkart, A. [Bonn University Hospital (Germany). Radiology; Bochum Univ. (Germany). Inst. of Medical Engineering

    2016-09-15

    To determine epicardial fat volume (EFV) and aortic stiffness (assessed by aortic pulse wave velocity (PWV)) in healthy individuals, and to investigate the relationship of these parameters, and their association with body mass index (BMI) and age. 58 subjects (29 men, mean age 44.7 ± 13.9 years[y]) underwent a CMR exam at 1.5 Tesla. A 2 D velocity-encoded CMR scan was acquired to determine PWV. The EFV was measured based on a 3 D-mDixon sequence. Group comparisons were made between younger (age < 45y; n=30; mean age 33.4 ± 6.6y) and older (> 45y; n=28; 56.7 ± 8.4y) subjects and between subjects with a BMI < 25 kg/m{sup 2} (n=28; BMI 21.9 ± 2.5 kg/m{sup 2}) and a BMI > 25 kg/m{sup 2} (n=30; 28.7 ± 4.0 kg/m{sup 2}). Associations between the determined parameters were assessed by analyses of covariance (ANCOVAs). The mean values of PWV and EFV (normalized to body surface area) were 6.9 ±1.9 m/s and 44.2 ± 25.0 ml/m{sup 2}, respectively. The PWV and EFV were significantly higher in the older group (PWV=7.9 ± 2.0 m/s vs. 6.0 ± 1.2 m/s; EFV=54.7 ml/m{sup 2} vs. 34.5 ml/m{sup 2}; p < 0.01, each), with no significant differences in BMI or sex. In the overweighted group the EFV was significantly higher than in subjects with a BMI < 25kg/m{sup 2} (EFV=56.1 ± 27.1 ml/m{sup 2} vs. 31.5 ± 14.6 ml/m{sup 2}; p < 0.01) but without a significant difference in PWV. ANCOVA revealed a significant correlation between EFV and PWV, also after adjustment for age (p=0.025). An association was found between age and EFV as well as PWV. EFV and PWV were related to each other also after adjustment for age. The metabolic and pro-inflammatory activity found with increased epicardial fat volume may promote the development of atherosclerosis and aortic stiffness. CMR may be valuable for future studies investigating the relationship between EFV and PWV in patients with increased cardiovascular risk.

  15. Quantitative detection and biological propagation of scrapie seeding activity in vitro facilitate use of prions as model pathogens for disinfection.

    Directory of Open Access Journals (Sweden)

    Sandra Pritzkow

    Full Text Available Prions are pathogens with an unusually high tolerance to inactivation and constitute a complex challenge to the re-processing of surgical instruments. On the other hand, however, they provide an informative paradigm which has been exploited successfully for the development of novel broad-range disinfectants simultaneously active also against bacteria, viruses and fungi. Here we report on the development of a methodological platform that further facilitates the use of scrapie prions as model pathogens for disinfection. We used specifically adapted serial protein misfolding cyclic amplification (PMCA for the quantitative detection, on steel wires providing model carriers for decontamination, of 263K scrapie seeding activity converting normal protease-sensitive into abnormal protease-resistant prion protein. Reference steel wires carrying defined amounts of scrapie infectivity were used for assay calibration, while scrapie-contaminated test steel wires were subjected to fifteen different procedures for disinfection that yielded scrapie titre reductions of ≤10(1- to ≥10(5.5-fold. As confirmed by titration in hamsters the residual scrapie infectivity on test wires could be reliably deduced for all examined disinfection procedures, from our quantitative seeding activity assay. Furthermore, we found that scrapie seeding activity present in 263K hamster brain homogenate or multiplied by PMCA of scrapie-contaminated steel wires both triggered accumulation of protease-resistant prion protein and was further propagated in a novel cell assay for 263K scrapie prions, i.e., cerebral glial cell cultures from hamsters. The findings from our PMCA- and glial cell culture assays revealed scrapie seeding activity as a biochemically and biologically replicative principle in vitro, with the former being quantitatively linked to prion infectivity detected on steel wires in vivo. When combined, our in vitro assays provide an alternative to titrations of biological

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

    Science.gov (United States)

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

    2012-01-01

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

  17. Electrons, Photons, and Force: Quantitative Single-Molecule Measurements from Physics to Biology

    Science.gov (United States)

    2011-01-01

    Single-molecule measurement techniques have illuminated unprecedented details of chemical behavior, including observations of the motion of a single molecule on a surface, and even the vibration of a single bond within a molecule. Such measurements are critical to our understanding of entities ranging from single atoms to the most complex protein assemblies. We provide an overview of the strikingly diverse classes of measurements that can be used to quantify single-molecule properties, including those of single macromolecules and single molecular assemblies, and discuss the quantitative insights they provide. Examples are drawn from across the single-molecule literature, ranging from ultrahigh vacuum scanning tunneling microscopy studies of adsorbate diffusion on surfaces to fluorescence studies of protein conformational changes in solution. PMID:21338175

  18. Quantitative assay of element mass inventories in single cell biological systems with micro-PIXE

    Energy Technology Data Exchange (ETDEWEB)

    Ogrinc, Nina [Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); LOTRIČ Metrology, Selca 163, SI-4227 Selca (Slovenia); Pelicon, Primož, E-mail: primoz.pelicon@ijs.si [Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); Vavpetič, Primož; Kelemen, Mitja; Grlj, Nataša; Jeromel, Luka [Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); Tomić, Sergej [Medical Faculty of the Military Medical Academy, University of Defense, Crnotravska 17, Belgrade (Serbia); Čolić, Miodrag [Medical Faculty of the Military Medical Academy, University of Defense, Crnotravska 17, Belgrade (Serbia); Medical Faculty, University of Niš, Boulevard of Dr. Zoran Djindjić 81, 18000 Niš (Serbia); Beran, Alfred [Dipartimento di Oceanografia Biologica, Istituto Nazionale di Oceanografia e Geofisica Sperimentale, Via Auguste Piccard 54, 34151 Trieste (Italy)

    2013-07-01

    Elemental concentrations in micro-PIXE (Particle Induced X-ray Emission) maps of elements in biological tissue slices have been determined using auxiliary information on the sample matrix composition from EBS (Elastic Backscattering Spectroscopy) and STIM (Scanning Transmission Ion Microscopy). The thin sample approximation may be used for evaluating micro-PIXE data in cases, where X-ray absorption in the sample can be neglected and the mass of elements in a selected area can be estimated. The resulting sensitivity amounts to an impressive 10{sup −12} g of the selected elements. Two cases are presented as examples. In the first, we determined the total mass of gold nanoparticles internalized by human monocyte-derived dendritic cells (MDDC). In the second, an inventory of the mass of elements in the micro-particulate material adsorbed at the wall of the lorica of the microzooplankton species Tintinnopsis radix has been created.

  19. Quantitative assay of element mass inventories in single cell biological systems with micro-PIXE

    International Nuclear Information System (INIS)

    Ogrinc, Nina; Pelicon, Primož; Vavpetič, Primož; Kelemen, Mitja; Grlj, Nataša; Jeromel, Luka; Tomić, Sergej; Čolić, Miodrag; Beran, Alfred

    2013-01-01

    Elemental concentrations in micro-PIXE (Particle Induced X-ray Emission) maps of elements in biological tissue slices have been determined using auxiliary information on the sample matrix composition from EBS (Elastic Backscattering Spectroscopy) and STIM (Scanning Transmission Ion Microscopy). The thin sample approximation may be used for evaluating micro-PIXE data in cases, where X-ray absorption in the sample can be neglected and the mass of elements in a selected area can be estimated. The resulting sensitivity amounts to an impressive 10 −12 g of the selected elements. Two cases are presented as examples. In the first, we determined the total mass of gold nanoparticles internalized by human monocyte-derived dendritic cells (MDDC). In the second, an inventory of the mass of elements in the micro-particulate material adsorbed at the wall of the lorica of the microzooplankton species Tintinnopsis radix has been created

  20. A New Technique for Quantitative Determination of Dexamethasone in Pharmaceutical and Biological Samples Using Kinetic Spectrophotometric Method

    Directory of Open Access Journals (Sweden)

    Ali Mohammad Akhoundi-Khalafi

    2015-01-01

    Full Text Available Dexamethasone is a type of steroidal medications that is prescribed in many cases. In this study, a new reaction system using kinetic spectrophotometric method for quantitative determination of dexamethasone is proposed. The method is based on the catalytic effect of dexamethasone on the oxidation of Orange G by bromate in acidic media. The change in absorbance as a criterion of the oxidation reaction progress was followed spectrophotometrically. To obtain the maximum sensitivity, the effective reaction variables were optimized. Under optimized experimental conditions, calibration graph was linear over the range 0.2–54.0 mg L−1. The calculated detection limit (3sb/m was 0.14 mg L−1 for six replicate determinations of blank signal. The interfering effect of various species was also investigated. The present method was successfully applied for the determination of dexamethasone in pharmaceutical and biological samples satisfactorily.

  1. Automatic definition of targeted biological volumes for the radiotherapy applications; Definition automatique des volumes biologiques cibles pour les applications de radiotherapie

    Energy Technology Data Exchange (ETDEWEB)

    Hatt, M.; Visvikis, D. [LaTIM, U650 Inserm, 29 - Brest (France); Cheze-Le-Rest, C. [Service de medecine nucleaire, 29 - Brest (France); Pradier, O. [Service de radiotherapie, 29 - Brest (France)

    2009-10-15

    The proposed method: Fuzzy locally adaptive Bayesian (F.L.A.B.) showed its reliability and its precision on very complete collection of realistic simulated and real data. Its use in the context of radiotherapy allows to consider easily the studies implementation and scenari of dose painting or dose escalation, including in complex cases of heterogenous fixations. It is conceivable to apply F.L.A.B. on PET images with F.M.I.S.O. ({sup 18}F fluoro misonidazole) or F.L.T. (fluoro-L-thymidine) to complete the definition of the biological target volume. (N.C.)

  2. Host cell proteins in biologics development: Identification, quantitation and risk assessment.

    Science.gov (United States)

    Wang, Xing; Hunter, Alan K; Mozier, Ned M

    2009-06-15

    Host cell proteins (HCPs) are those produced or encoded by the organisms and unrelated to the intended recombinant product. Some are necessary for growth, survival, and normal cellular processing whereas others may be non-essential, simply carried along as baggage. Like the recombinant product, HCPs may also be modified by the host with a number of post-translational modifications. Regardless of the utility, or lack thereof, HCPs are undesirable in the final drug substance. Though commonly present in small quantities (parts per million expressed as nanograms per milligrams of the intended recombinant protein) much effort and cost is expended by industry to remove them. The purpose of this review is to summarize what is of relevance in regards to the biology, the impact of genomics and proteomics on HCP evaluation, the regulatory expectations, analytical approaches, and various methodologies to remove HCPs with bioprocessing. Historical data, bioinformatics approaches and industrial case study examples are provided. Finally, a proposal for a risk assessment tool is provided which brings these facets together and proposes a means for manufacturers to classify and organize a control strategy leading to meaningful product specifications. 2009 Wiley Periodicals, Inc.

  3. Three molecular forms of atrial natriuretic peptides: quantitative analysis and biological characterization.

    Science.gov (United States)

    Nagai-Okatani, Chiaki; Kangawa, Kenji; Minamino, Naoto

    2017-07-01

    Atrial natriuretic peptide (ANP) is primarily produced in the heart tissue and plays a pivotal role in maintaining cardiovascular homeostasis in endocrine and autocrine/paracrine systems and has clinical applications as a biomarker and a therapeutic agent for cardiac diseases. ANP is synthesized by atrial cardiomyocytes as a preprohormone that is processed by a signal peptidase and stored in secretory granules as a prohormone. Subsequent proteolytic processing of ANP by corin during the secretion process results in a bioactive form consisting of 28 amino acid residues. Mechanical stretch of the atrial wall and multiple humoral factors directly stimulates the transcription and secretion of ANP. Secreted ANP elicits natriuretic and diuretic effects via cyclic guanosine monophosphate produced through binding to the guanylyl cyclase-A/natriuretic peptide receptor-A. Circulating ANP is subjected to rapid clearance by a natriuretic peptide receptor-C-mediated mechanism and proteolytic degradation by neutral endopeptidase. In humans, ANP is present as three endogenous molecular forms: bioactive α-ANP, a homodimer of α-ANP designated as β-ANP, and an ANP precursor designated as proANP (also referred to as γ-ANP). The proANP and especially β-ANP, as minor forms in circulation, are notably increased in patients with cardiac diseases, suggesting the utility of monitoring the pathophysiological conditions that result in abnormal proANP processing that cannot be monitored by inactive N-terminal proANP-related fragments. Emerging plate-based sandwich immunoassays for individual quantitation of the three ANP forms enables evaluation of diagnostic implications and net ANP bioactivity. This new tool may provide further understanding in the pathophysiology of cardiac diseases. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd.

  4. A retrospective cross-sectional quantitative molecular approach in biological samples from patients with syphilis.

    Science.gov (United States)

    Pinto, Miguel; Antelo, Minia; Ferreira, Rita; Azevedo, Jacinta; Santo, Irene; Borrego, Maria José; Gomes, João Paulo

    2017-03-01

    Syphilis is the sexually transmitted disease caused by Treponema pallidum, a pathogen highly adapted to the human host. As a multistage disease, syphilis presents distinct clinical manifestations that pose different implications for diagnosis. Nevertheless, the inherent factors leading to diverse disease progressions are still unknown. We aimed to assess the association between treponemal loads and dissimilar disease outcomes, to better understand syphilis. We retrospectively analyzed 309 DNA samples distinct anatomic sites associated with particular syphilis manifestations. All samples had previously tested positive by a PCR-based diagnostic kit. An absolute quantitative real-time PCR procedure was used to precisely quantify the number of treponemal and human cells to determine T. pallidum loads in each sample. In general, lesion exudates presented the highest T. pallidum loads in contrast with blood-derived samples. Within the latter, a higher dispersion of T. pallidum quantities was observed for secondary syphilis. T. pallidum was detected in substantial amounts in 37 samples of seronegative individuals and in 13 cases considered as syphilis-treated. No association was found between treponemal loads and serological results or HIV status. This study suggests a scenario where syphilis may be characterized by: i) heterogeneous and high treponemal loads in primary syphilis, regardless of the anatomic site, reflecting dissimilar duration of chancres development and resolution; ii) high dispersion of bacterial concentrations in secondary syphilis, potentially suggesting replication capability of T. pallidum while in the bloodstream; and iii) bacterial evasiveness, either to the host immune system or antibiotic treatment, while remaining hidden in privileged niches. This work highlights the importance of using molecular approaches to study uncultivable human pathogens, such as T. pallidum, in the infection process. Copyright © 2017 Elsevier Ltd. All rights

  5. Quantitative global and gene-specific promoter methylation in relation to biological properties of neuroblastomas

    Directory of Open Access Journals (Sweden)

    Kiss Nimrod B

    2012-09-01

    Full Text Available Abstract Background In this study we aimed to quantify tumor suppressor gene (TSG promoter methylation densities levels in primary neuroblastoma tumors and cell lines. A subset of these TSGs is associated with a CpG island methylator phenotype (CIMP in other tumor types. Methods The study panel consisted of 38 primary tumors, 7 established cell lines and 4 healthy references. Promoter methylation was determined by bisulphate Pyrosequencing for 14 TSGs; and LINE-1 repeat element methylation was used as an indicator of global methylation levels. Results Overall mean TSG Z-scores were significantly increased in cases with adverse outcome, but were unrelated to global LINE-1 methylation. CIMP with hypermethylation of three or more gene promoters was observed in 6/38 tumors and 7/7 cell lines. Hypermethylation of one or more TSG (comprising TSGs BLU, CASP8, DCR2, CDH1, RASSF1A and RASSF2 was evident in 30/38 tumors. By contrast only very low levels of promoter methylation were recorded for APC, DAPK1, NORE1A, P14, P16, TP73, PTEN and RARB. Similar involvements of methylation instability were revealed between cell line models and neuroblastoma tumors. Separate analysis of two proposed CASP8 regulatory regions revealed frequent and significant involvement of CpG sites between exon 4 and 5, but modest involvement of the exon 1 region. Conclusions/significance The results highlight the involvement of TSG methylation instability in neuroblastoma tumors and cell lines using quantitative methods, support the use of DNA methylation analyses as a prognostic tool for this tumor type, and underscore the relevance of developing demethylating therapies for its treatment.

  6. Atlas based brain volumetry: How to distinguish regional volume changes due to biological or physiological effects from inherent noise of the methodology.

    Science.gov (United States)

    Opfer, Roland; Suppa, Per; Kepp, Timo; Spies, Lothar; Schippling, Sven; Huppertz, Hans-Jürgen

    2016-05-01

    Fully-automated regional brain volumetry based on structural magnetic resonance imaging (MRI) plays an important role in quantitative neuroimaging. In clinical trials as well as in clinical routine multiple MRIs of individual patients at different time points need to be assessed longitudinally. Measures of inter- and intrascanner variability are crucial to understand the intrinsic variability of the method and to distinguish volume changes due to biological or physiological effects from inherent noise of the methodology. To measure regional brain volumes an atlas based volumetry (ABV) approach was deployed using a highly elastic registration framework and an anatomical atlas in a well-defined template space. We assessed inter- and intrascanner variability of the method in 51 cognitively normal subjects and 27 Alzheimer dementia (AD) patients from the Alzheimer's Disease Neuroimaging Initiative by studying volumetric results of repeated scans for 17 compartments and brain regions. Median percentage volume differences of scan-rescans from the same scanner ranged from 0.24% (whole brain parenchyma in healthy subjects) to 1.73% (occipital lobe white matter in AD), with generally higher differences in AD patients as compared to normal subjects (e.g., 1.01% vs. 0.78% for the hippocampus). Minimum percentage volume differences detectable with an error probability of 5% were in the one-digit percentage range for almost all structures investigated, with most of them being below 5%. Intrascanner variability was independent of magnetic field strength. The median interscanner variability was up to ten times higher than the intrascanner variability. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. A bench-top K X-ray fluorescence system for quantitative measurement of gold nanoparticles for biological sample diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Ricketts, K., E-mail: k.ricketts@ucl.ac.uk [Division of Surgery and Interventional Sciences, University College London, Royal Free Campus, Rowland Hill Street, London NW3 2PF (United Kingdom); Guazzoni, C.; Castoldi, A. [Dipartimento di Elettronica, Informazione e Bioingegneria Politecnico di Milano and INFN, Sezione di Milano P.za Leonardo da Vinci, 32-20133 Milano (Italy); Royle, G. [Department of Medical Physics and Bioengineering, University College London, Malet Place Engineering Building, Gower Street, London WC1E 6BT (United Kingdom)

    2016-04-21

    Gold nanoparticles can be targeted to biomarkers to give functional information on a range of tumour characteristics. X-ray fluorescence (XRF) techniques offer potential quantitative measurement of the distribution of such heavy metal nanoparticles. Biologists are developing 3D tissue engineered cellular models on the centimetre scale to optimise targeting techniques of nanoparticles to a range of tumour characteristics. Here we present a high energy bench-top K-X-ray fluorescence system designed for sensitivity to bulk measurement of gold nanoparticle concentration for intended use in such thick biological samples. Previous work has demonstrated use of a L-XRF system in measuring gold concentrations but being a low energy technique it is restricted to thin samples or superficial tumours. The presented system comprised a high purity germanium detector and filtered tungsten X-ray source, capable of quantitative measurement of gold nanoparticle concentration of thicker samples. The developed system achieved a measured detection limit of between 0.2 and 0.6 mgAu/ml, meeting specifications of biologists and being approximately one order of magnitude better than the detection limit of alternative K-XRF nanoparticle detection techniques. The scatter-corrected K-XRF signal of gold was linear with GNP concentrations down to the detection limit, thus demonstrating potential in GNP concentration quantification. The K-XRF system demonstrated between 5 and 9 times less sensitivity than a previous L-XRF bench-top system, due to a fundamental limitation of lower photoelectric interaction probabilities at higher K-edge energies. Importantly, the K-XRF technique is however less affected by overlying thickness, and so offers future potential in interrogating thick biological samples.

  8. Quantitative global sensitivity analysis of a biologically based dose-response pregnancy model for the thyroid endocrine system.

    Science.gov (United States)

    Lumen, Annie; McNally, Kevin; George, Nysia; Fisher, Jeffrey W; Loizou, George D

    2015-01-01

    A deterministic biologically based dose-response model for the thyroidal system in a near-term pregnant woman and the fetus was recently developed to evaluate quantitatively thyroid hormone perturbations. The current work focuses on conducting a quantitative global sensitivity analysis on this complex model to identify and characterize the sources and contributions of uncertainties in the predicted model output. The workflow and methodologies suitable for computationally expensive models, such as the Morris screening method and Gaussian Emulation processes, were used for the implementation of the global sensitivity analysis. Sensitivity indices, such as main, total and interaction effects, were computed for a screened set of the total thyroidal system descriptive model input parameters. Furthermore, a narrower sub-set of the most influential parameters affecting the model output of maternal thyroid hormone levels were identified in addition to the characterization of their overall and pair-wise parameter interaction quotients. The characteristic trends of influence in model output for each of these individual model input parameters over their plausible ranges were elucidated using Gaussian Emulation processes. Through global sensitivity analysis we have gained a better understanding of the model behavior and performance beyond the domains of observation by the simultaneous variation in model inputs over their range of plausible uncertainties. The sensitivity analysis helped identify parameters that determine the driving mechanisms of the maternal and fetal iodide kinetics, thyroid function and their interactions, and contributed to an improved understanding of the system modeled. We have thus demonstrated the use and application of global sensitivity analysis for a biologically based dose-response model for sensitive life-stages such as pregnancy that provides richer information on the model and the thyroidal system modeled compared to local sensitivity analysis.

  9. Effects of Single and Combined Application of Organic and Biological Fertilizers on Quantitative and Qualitative Yield of Anisum (Pimpinella anisum

    Directory of Open Access Journals (Sweden)

    N Kamayestani

    2015-07-01

    Full Text Available In order to study the effects of single and combined applications of biofertilazer and organic fertilizers on quantitative and qualitative characteristics of anisum (Pimpinella anisum, an experiment was conducted based on a Randomized Complete Block Design with three replications and fifteen treatments at Research Station, Faculty of Agriculture, Ferdowsi University of Mashhad, Iran, in 2011 year. Treatments were: (1 mycorrhiza (Glomus intraradices, (2 mycorrhiza + cow manure, (3 mycorrhiza + vermicompost, (4 mycorrhiza+ compost, (5 mycorrhiza + chemical fertilizer, (6 biosulfur (Thiobacillus sp. + Bentonite, (7 biosulfur + chemical fertilizer, (8 biosulfur + cow manure, (9 biosulfur + vermicompost, (10 biosulfur+compost,11 (cow manure, (12 vermicompost, (13 chemical fertilizer (NPK, (14compost and (15 control. The results showed that application of fertilizer treatments had significant effect on most characteristics of anisum. The highest number of seed per umbelet (7.24, economic yield (1263.4kg/ha were obtained fram biosulfur treatment. The highest dry matter yield (4504.1 kg/ha resulted from combined application of biosulfur + chemical fertilizer and the highest harvest index (25.97% observed in biosulfur+cow manure. The combined application of mycorrhiza affected some qualification traits, as the highest number of umbel per plant (65.7, 1000 seed-weight (3.24 g and essential oil percentage (5.3% resulted from combined application of mycorrhiza+chemical fertilizer. In general, it can be concluded that application of organic and biological fertilizer particularly mycorrhiza and biosulfur had a significant effect on improving of quantitative and qualitative characteristics of anisum. Furthermore, the combined application of organic and biological fertilizer had higher positive effects than their single application.

  10. Quantitative global sensitivity analysis of a biologically based dose-response pregnancy model for the thyroid endocrine system

    Directory of Open Access Journals (Sweden)

    Annie eLumen

    2015-05-01

    Full Text Available A deterministic biologically based dose-response model for the thyroidal system in a near-term pregnant woman and the fetus was recently developed to evaluate quantitatively thyroid hormone perturbations. The current work focuses on conducting a quantitative global sensitivity analysis on this complex model to identify and characterize the sources and contributions of uncertainties in the predicted model output. The workflow and methodologies suitable for computationally expensive models, such as the Morris screening method and Gaussian Emulation processes, were used for the implementation of the global sensitivity analysis. Sensitivity indices, such as main, total and interaction effects, were computed for a screened set of the total thyroidal system descriptive model input parameters. Furthermore, a narrower sub-set of the most influential parameters affecting the model output of maternal thyroid hormone levels were identified in addition to the characterization of their overall and pair-wise parameter interaction quotients. The characteristic trends of influence in model output for each of these individual model input parameters over their plausible ranges were elucidated using Gaussian Emulation processes. Through global sensitivity analysis we have gained a better understanding of the model behavior and performance beyond the domains of observation by the simultaneous variation in model inputs over their range of plausible uncertainties. The sensitivity analysis helped identify parameters that determine the driving mechanisms of the maternal and fetal iodide kinetics, thyroid function and their interactions, and contributed to an improved understanding of the system modeled. We have thus demonstrated the use and application of global sensitivity analysis for a biologically based dose-response model for sensitive life-stages such as pregnancy that provides richer information on the model and the thyroidal system modeled compared to local

  11. Quantitating morphological changes in biological samples during scanning electron microscopy sample preparation with correlative super-resolution microscopy.

    Science.gov (United States)

    Zhang, Ying; Huang, Tao; Jorgens, Danielle M; Nickerson, Andrew; Lin, Li-Jung; Pelz, Joshua; Gray, Joe W; López, Claudia S; Nan, Xiaolin

    2017-01-01

    Sample preparation is critical to biological electron microscopy (EM), and there have been continuous efforts on optimizing the procedures to best preserve structures of interest in the sample. However, a quantitative characterization of the morphological changes associated with each step in EM sample preparation is currently lacking. Using correlative EM and superresolution microscopy (SRM), we have examined the effects of different drying methods as well as osmium tetroxide (OsO4) post-fixation on cell morphology during scanning electron microscopy (SEM) sample preparation. Here, SRM images of the sample acquired under hydrated conditions were used as a baseline for evaluating morphological changes as the sample went through SEM sample processing. We found that both chemical drying and critical point drying lead to a mild cellular boundary retraction of ~60 nm. Post-fixation by OsO4 causes at least 40 nm additional boundary retraction. We also found that coating coverslips with adhesion molecules such as fibronectin prior to cell plating helps reduce cell distortion from OsO4 post-fixation. These quantitative measurements offer useful information for identifying causes of cell distortions in SEM sample preparation and improving current procedures.

  12. Common biology of craving across legal and illegal drugs - a quantitative meta-analysis of cue-reactivity brain response.

    Science.gov (United States)

    Kühn, Simone; Gallinat, Jürgen

    2011-04-01

    The present quantitative meta-analysis set out to test whether cue-reactivity responses in humans differ across drugs of abuse and whether these responses constitute the biological basis of drug craving as a core psychopathology of addiction. By means of activation likelihood estimation, we investigated the concurrence of brain regions activated by cue-induced craving paradigms across studies on nicotine, alcohol and cocaine addicts. Furthermore, we analysed the concurrence of brain regions positively correlated with self-reported craving in nicotine and alcohol studies. We found direct overlap between nicotine, alcohol and cocaine cue reactivity in the ventral striatum. In addition, regions of close proximity were observed in the anterior cingulate cortex (ACC; nicotine and cocaine) and amygdala (alcohol, nicotine and cocaine). Brain regions of concurrence in drug cue-reactivity paradigms that overlapped with brain regions of concurrence in self-reported craving correlations were found in the ACC, ventral striatum and right pallidum (for alcohol). This first quantitative meta-analysis on drug cue reactivity identifies brain regions underlying nicotine, alcohol and cocaine dependency, i.e. the ventral striatum. The ACC, right pallidum and ventral striatum were related to drug cue reactivity as well as self-reported craving, suggesting that this set of brain regions constitutes the core circuit of drug craving in nicotine and alcohol addiction. © 2011 The Authors. European Journal of Neuroscience © 2011 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

  13. 3-Dimensional quantitative detection of nanoparticle content in biological tissue samples after local cancer treatment

    Energy Technology Data Exchange (ETDEWEB)

    Rahn, Helene, E-mail: helene.rahn@gmail.com [Institute of Fluid Mechanics, Chair of Magnetofluiddynamics, Technische Universitaet Dresden, Dresden 01069 (Germany); Alexiou, Christoph [ENT-Department, Section for Experimental Oncology and Nanomedicine (Else Kröner-Fresenius-Stiftungsprofessur), University Hospital Erlangen, Waldstraße 1, Erlangen 91054 (Germany); Trahms, Lutz [Physikalisch-Technische Bundesanstalt, Abbestraße 2-12, Berlin 10587 (Germany); Odenbach, Stefan [Institute of Fluid Mechanics, Chair of Magnetofluiddynamics, Technische Universitaet Dresden, Dresden 01069 (Germany)

    2014-06-01

    X-ray computed tomography is nowadays used for a wide range of applications in medicine, science and technology. X-ray microcomputed tomography (XµCT) follows the same principles used for conventional medical CT scanners, but improves the spatial resolution to a few micrometers. We present an example of an application of X-ray microtomography, a study of 3-dimensional biodistribution, as along with the quantification of nanoparticle content in tumoral tissue after minimally invasive cancer therapy. One of these minimal invasive cancer treatments is magnetic drug targeting, where the magnetic nanoparticles are used as controllable drug carriers. The quantification is based on a calibration of the XµCT-equipment. The developed calibration procedure of the X-ray-µCT-equipment is based on a phantom system which allows the discrimination between the various gray values of the data set. These phantoms consist of a biological tissue substitute and magnetic nanoparticles. The phantoms have been studied with XµCT and have been examined magnetically. The obtained gray values and nanoparticle concentration lead to a calibration curve. This curve can be applied to tomographic data sets. Accordingly, this calibration enables a voxel-wise assignment of gray values in the digital tomographic data set to nanoparticle content. Thus, the calibration procedure enables a 3-dimensional study of nanoparticle distribution as well as concentration. - Highlights: • Local cancer treatments are promising in reducing negative side effects occurring during conventional chemotherapy. • The nanoparticles play an important role in delivering drugs to the designated area during local cancer treatments as magnetic drug targeting. • We study the nanoparticles distribution in tumor tissue after magnetic drug targeting with X-ray computed tomography. • We achieved a 3-dimensional quantification of the nanoparticles content in tumor tissue out of digital tomographic data.

  14. CADDIS Volume 4. Data Analysis: Predicting Environmental Conditions from Biological Observations (PECBO Appendix)

    Science.gov (United States)

    Overview of PECBO Module, using scripts to infer environmental conditions from biological observations, statistically estimating species-environment relationships, methods for inferring environmental conditions, statistical scripts in module.

  15. BEDVH--A method for evaluating biologically effective dose volume histograms: Application to eye plaque brachytherapy implants

    International Nuclear Information System (INIS)

    Gagne, Nolan L.; Leonard, Kara L.; Huber, Kathryn E.; Mignano, John E.; Duker, Jay S.; Laver, Nora V.; Rivard, Mark J.

    2012-01-01

    Purpose: A method is introduced to examine the influence of implant duration T, radionuclide, and radiobiological parameters on the biologically effective dose (BED) throughout the entire volume of regions of interest for episcleral brachytherapy using available radionuclides. This method is employed to evaluate a particular eye plaque brachytherapy implant in a radiobiological context. Methods: A reference eye geometry and 16 mm COMS eye plaque loaded with 103 Pd, 125 I, or 131 Cs sources were examined with dose distributions accounting for plaque heterogeneities. For a standardized 7 day implant, doses to 90% of the tumor volume ( TUMOR D 90 ) and 10% of the organ at risk volumes ( OAR D 10 ) were calculated. The BED equation from Dale and Jones and published α/β and μ parameters were incorporated with dose volume histograms (DVHs) for various T values such as T = 7 days (i.e., TUMOR 7 BED 10 and OAR 7 BED 10 ). By calculating BED throughout the volumes, biologically effective dose volume histograms (BEDVHs) were developed for tumor and OARs. Influence of T, radionuclide choice, and radiobiological parameters on TUMOR BEDVH and OAR BEDVH were examined. The nominal dose was scaled for shorter implants to achieve biological equivalence. Results: TUMOR D 90 values were 102, 112, and 110 Gy for 103 Pd, 125 I, and 131 Cs, respectively. Corresponding TUMOR 7 BED 10 values were 124, 140, and 138 Gy, respectively. As T decreased from 7 to 0.01 days, the isobiologically effective prescription dose decreased by a factor of three. As expected, TUMOR 7 BEDVH did not significantly change as a function of radionuclide half-life but varied by 10% due to radionuclide dose distribution. Variations in reported radiobiological parameters caused TUMOR 7 BED 10 to deviate by up to 46%. Over the range of OAR α/β values, OAR 7 BED 10 varied by up to 41%, 3.1%, and 1.4% for the lens, optic nerve, and lacrimal gland, respectively. Conclusions: BEDVH permits evaluation of the

  16. Utility of Quantitative Tc-MAA SPECT/CT for yttrium-Labelled Microsphere Treatment Planning: Calculating Vascularized Hepatic Volume and Dosimetric Approach.

    Science.gov (United States)

    Garin, Etienne; Rolland, Yan; Lenoir, Laurence; Pracht, Marc; Mesbah, Habiba; Porée, Philippe; Laffont, Sophie; Clement, Bruno; Raoul, Jean-Luc; Boucher, Eveline

    2011-01-01

    Objectives. The aim of this study was to assess the effectiveness of SPECT/CT for volume measurements and to report a case illustrating the major impact of SPECT/CT in calculating the vascularized liver volume and dosimetry prior to injecting radiolabelled yttrium-90 microspheres (Therasphere). Materials and Methods. This was a phantom study, involving volume measurements carried out by two operators using SPECT and SPECT/CT images. The percentage of error for each method was calculated, and interobserver reproducibility was evaluated. A treatment using Therasphere was planned in a patient with three hepatic arteries, and the quantitative analysis of SPECT/CT for this patient is provided. Results. SPECT/CT volume measurements proved to be accurate (mean error Therasphere used. Conclusions. MAA SPECT/CT is accurate for vascularized liver volume measurements, providing a valuable contribution to the therapeutic planning of patients with complex hepatic vascularization.

  17. Utility of Quantitative 99mTc-MAA SPECT/CT for 90yttrium-Labelled Microsphere Treatment Planning: Calculating Vascularized Hepatic Volume and Dosimetric Approach

    Science.gov (United States)

    Garin, Etienne; Rolland, Yan; Lenoir, Laurence; Pracht, Marc; Mesbah, Habiba; Porée, Philippe; Laffont, Sophie; Clement, Bruno; Raoul, Jean-Luc; Boucher, Eveline

    2011-01-01

    Objectives. The aim of this study was to assess the effectiveness of SPECT/CT for volume measurements and to report a case illustrating the major impact of SPECT/CT in calculating the vascularized liver volume and dosimetry prior to injecting radiolabelled yttrium-90 microspheres (Therasphere). Materials and Methods. This was a phantom study, involving volume measurements carried out by two operators using SPECT and SPECT/CT images. The percentage of error for each method was calculated, and interobserver reproducibility was evaluated. A treatment using Therasphere was planned in a patient with three hepatic arteries, and the quantitative analysis of SPECT/CT for this patient is provided. Results. SPECT/CT volume measurements proved to be accurate (mean error Therasphere used. Conclusions. MAA SPECT/CT is accurate for vascularized liver volume measurements, providing a valuable contribution to the therapeutic planning of patients with complex hepatic vascularization. PMID:21822489

  18. Quantitative analysis of rat adipose tissue cell recovery, and non-fat cell volume, in primary cell cultures

    Directory of Open Access Journals (Sweden)

    Floriana Rotondo

    2016-11-01

    Full Text Available Background White adipose tissue (WAT is a complex, diffuse, multifunctional organ which contains adipocytes, and a large proportion of fat, but also other cell types, active in defense, regeneration and signalling functions. Studies with adipocytes often require their isolation from WAT by breaking up the matrix of collagen fibres; however, it is unclear to what extent adipocyte number in primary cultures correlates with their number in intact WAT, since recovery and viability are often unknown. Experimental Design Epididymal WAT of four young adult rats was used to isolate adipocytes with collagenase. Careful recording of lipid content of tissue, and all fraction volumes and weights, allowed us to trace the amount of initial WAT fat remaining in the cell preparation. Functionality was estimated by incubation with glucose and measurement of glucose uptake and lactate, glycerol and NEFA excretion rates up to 48 h. Non-adipocyte cells were also recovered and their sizes (and those of adipocytes were measured. The presence of non-nucleated cells (erythrocytes was also estimated. Results Cell numbers and sizes were correlated from all fractions to intact WAT. Tracing the lipid content, the recovery of adipocytes in the final, metabolically active, preparation was in the range of 70–75%. Cells showed even higher metabolic activity in the second than in the first day of incubation. Adipocytes were 7%, erythrocytes 66% and other stromal (nucleated cells 27% of total WAT cells. However, their overall volumes were 90%, 0.05%, and 0.2% of WAT. Non-fat volume of adipocytes was 1.3% of WAT. Conclusions The methodology presented here allows for a direct quantitative reference to the original tissue of studies using isolated cells. We have also found that the “live cell mass” of adipose tissue is very small: about 13 µL/g for adipocytes and 2 µL/g stromal, plus about 1 µL/g blood (the rats were killed by exsanguination. These data translate (with

  19. Quantitative agreement between [(15)O]H2O PET and model free QUASAR MRI-derived cerebral blood flow and arterial blood volume

    NARCIS (Netherlands)

    Heijtel, D. F. R.; Petersen, E. T.; Mutsaerts, H. J. M. M.; Bakker, E.; Schober, P.; Stevens, M. F.; van Berckel, B. N. M.; Majoie, C. B. L. M.; Booij, J.; van Osch, M. J. P.; van Bavel, E. T.; Boellaard, R.; Lammertsma, A. A.; Nederveen, A. J.

    2016-01-01

    The purpose of this study was to assess whether there was an agreement between quantitative cerebral blood flow (CBF) and arterial cerebral blood volume (CBVA) measurements by [(15)O]H2O positron emission tomography (PET) and model-free QUASAR MRI. Twelve healthy subjects were scanned within a week

  20. Correction for Partial Volume Effect Is a Must, Not a Luxury, to Fully Exploit the Potential of Quantitative PET Imaging in Clinical Oncology

    DEFF Research Database (Denmark)

    Alavi, Abass; Werner, Thomas J; Høilund-Carlsen, Poul Flemming

    2018-01-01

    The partial volume effect (PVE) is considered as one of the major degrading factors impacting image quality and hampering the accuracy of quantitative PET imaging in clinical oncology. This effect is the consequence of the limited spatial resolution of whole-body PET scanners, which results in bl...

  1. Australian Biology Test Item Bank, Years 11 and 12. Volume II: Year 12.

    Science.gov (United States)

    Brown, David W., Ed.; Sewell, Jeffrey J., Ed.

    This document consists of test items which are applicable to biology courses throughout Australia (irrespective of course materials used); assess key concepts within course statement (for both core and optional studies); assess a wide range of cognitive processes; and are relevant to current biological concepts. These items are arranged under…

  2. Australian Biology Test Item Bank, Years 11 and 12. Volume I: Year 11.

    Science.gov (United States)

    Brown, David W., Ed.; Sewell, Jeffrey J., Ed.

    This document consists of test items which are applicable to biology courses throughout Australia (irrespective of course materials used); assess key concepts within course statement (for both core and optional studies); assess a wide range of cognitive processes; and are relevant to current biological concepts. These items are arranged under…

  3. Comparison of standardized uptake values with volume of distribution for quantitation of [11C]PBR28 brain uptake

    International Nuclear Information System (INIS)

    Yoder, Karmen K.; Territo, Paul R.; Hutchins, Gary D.; Hannestad, Jonas; Morris, Evan D.; Gallezot, Jean-Dominique; Normandin, Marc D.; Cosgrove, Kelly P.

    2015-01-01

    Introduction: [ 11 C]PBR28 is a high-affinity ligand for the Translocator Protein 18 kDa (TSPO), which is considered to be a marker for microglial activation. Volume of distribution (V T ) estimated with an arterial plasma input function is the gold standard for quantitation of [ 11 C]PBR28 binding. However, arterial sampling is impractical at many PET sites for multiple reasons. Reference region modeling approaches are not ideal for TSPO tracers, as the existence of a true reference region cannot be assumed. Given that it would be desirable to have a non-invasive index of [ 11 C]PBR28 binding, we elected to study the utility of the semi-quantitative metric, standardized uptake value (SUV) for use in brain [ 11 C]PBR PET studies. The primary goal of this study was to determine the relationship between SUV and V T . Methods: We performed a retrospective analysis of data from sixteen [ 11 C]PBR28 PET scans acquired in baboons at baseline and at multiple time points after IV injection of lipopolysaccharide, an endotoxin that transiently induces neuroinflammation. For each scan, data from 14 brain regions of interest were studied. V T was estimated with the Logan plot, using metabolite-corrected input functions. SUV was calculated with data from 30 to 60 minutes after [ 11 C]PBR28 injection. Results: Within individual PET studies, SUV tended to correlate well with V T . Across studies, the relationship between SUV and V T was variable. Conclusions: From study to study, there was variability in the degree of correlation between [ 11 C]PBR28 V T and SUV. There are multiple physiological factors that may contribute to this variance. Advances in Knowledge: As currently applied, the non-invasive measurement of SUV does not appear to be a reliable outcome variable for [ 11 C]PBR28. Additional work is needed to discover the source of the discrepancy in SUV between [ 11 C]PBR28 scans. Implications for Patient Care: There is a need to develop alternatives to arterial plasma

  4. Influence of magnification on the calculated value of left ventricular ejection fraction and volumes using quantitative gated perfusion SPECT

    International Nuclear Information System (INIS)

    Nunez, M.; Beretta, M.; Alonso, O.; Alvarez, B.; Canepa, J.; Mut, F.

    2002-01-01

    Aim: To compare left ventricular ejection fraction (LVEF), end-diastolic volumes (EDV) and end-systolic volumes (ESV) measured by quantitative gated SPECT (QGSPECT) in studies acquired with and without magnification factor (zoom). Material and Methods: We studied 30 consecutive patients (17 men, ages 61±14 years) referred for myocardial perfusion evaluation with a 2-day protocol. Studies were performed after injection of 925 MBq (25 mCi) of 99mTc-MIBI in the resting state. Gated SPECT was first acquired using a x2 zoom factor and immediately repeated with x1 zoom (no magnification), using a 64x64 matrix and 8 frames/cardiac cycle. Patients with arrhythmia were not included in the investigation. According to the median EDV calculated with the x2 zoom acquisition, the population was further divided in two sub-groups regarding the size of the LV cavity. Average LVEF, EDV, ESV and difference between values (delta) were then calculated for the total population and for each sub-group (a and b). Results: For the total population, results are expressed.Pearson correlation showed r=0.954 between LVEF with and without zoom (p<0.0001), but linear regression analysis did not fit a specific model (p=0.18). Median EDV with zoom was 92.5 ml, allowing to separate 15 cases with EDV above (a) and 15 below that value (b). Results for both sub-groups are presented. Conclusion: Calculated LVEF is higher with no zoom, at the expense of decreasing both EDV and ESV. Although differences were very significant for all parameters, ESV changes were specially relevant with no zoom, particularly in patients with smaller hearts. Although good correlation was found between LVEF with and without zoom, no specific correction factor was found to convert one value into the other. Magnification factor should be kept constant in gated SPECT if calculated LVEF values QGSPECT are expected to be reliable, and validation of the method using different zoom factors should be considered

  5. Volume Tracking: A new method for quantitative assessment and visualization of intracardiac blood flow from three-dimensional, time-resolved, three-component magnetic resonance velocity mapping

    International Nuclear Information System (INIS)

    Töger, Johannes; Carlsson, Marcus; Söderlind, Gustaf; Arheden, Håkan; Heiberg, Einar

    2011-01-01

    Functional and morphological changes of the heart influence blood flow patterns. Therefore, flow patterns may carry diagnostic and prognostic information. Three-dimensional, time-resolved, three-directional phase contrast cardiovascular magnetic resonance (4D PC-CMR) can image flow patterns with unique detail, and using new flow visualization methods may lead to new insights. The aim of this study is to present and validate a novel visualization method with a quantitative potential for blood flow from 4D PC-CMR, called Volume Tracking, and investigate if Volume Tracking complements particle tracing, the most common visualization method used today. Eight healthy volunteers and one patient with a large apical left ventricular aneurysm underwent 4D PC-CMR flow imaging of the whole heart. Volume Tracking and particle tracing visualizations were compared visually side-by-side in a visualization software package. To validate Volume Tracking, the number of particle traces that agreed with the Volume Tracking visualizations was counted and expressed as a percentage of total released particles in mid-diastole and end-diastole respectively. Two independent observers described blood flow patterns in the left ventricle using Volume Tracking visualizations. Volume Tracking was feasible in all eight healthy volunteers and in the patient. Visually, Volume Tracking and particle tracing are complementary methods, showing different aspects of the flow. When validated against particle tracing, on average 90.5% and 87.8% of the particles agreed with the Volume Tracking surface in mid-diastole and end-diastole respectively. Inflow patterns in the left ventricle varied between the subjects, with excellent agreement between observers. The left ventricular inflow pattern in the patient differed from the healthy subjects. Volume Tracking is a new visualization method for blood flow measured by 4D PC-CMR. Volume Tracking complements and provides incremental information compared to particle

  6. Imaging and quantitative data acquisition of biological cell walls with Atomic Force Microscopy and Scanning Acoustic Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Tittmann, B. R. [Penn State; Xi, X. [Penn State

    2014-09-01

    This chapter demonstrates the feasibility of Atomic Force Microscopy (AFM) and High Frequency Scanning Acoustic Microscopy (HF-SAM) as tools to characterize biological tissues. Both the AFM and the SAM have shown to provide imaging (with different resolution) and quantitative elasticity measuring abilities. Plant cell walls with minimal disturbance and under conditions of their native state have been examined with these two kinds of microscopy. After descriptions of both the SAM and AFM, their special features and the typical sample preparation is discussed. The sample preparation is focused here on epidermal peels of onion scales and celery epidermis cells which were sectioned for the AFM to visualize the inner surface (closest to the plasma membrane) of the outer epidermal wall. The nm-wide cellulose microfibrils orientation and multilayer structure were clearly observed. The microfibril orientation and alignment tend to be more organized in older scales compared with younger scales. The onion epidermis cell wall was also used as a test analog to study cell wall elasticity by the AFM nanoindentation and the SAM V(z) feature. The novelty in this work was to demonstrate the capability of these two techniques to analyze isolated, single layered plant cell walls in their natural state. AFM nanoindentation was also used to probe the effects of Ethylenediaminetetraacetic acid (EDTA), and calcium ion treatment to modify pectin networks in cell walls. The results suggest a significant modulus increase in the calcium ion treatment and a slight decrease in EDTA treatment. To complement the AFM measurements, the HF-SAM was used to obtain the V(z) signatures of the onion epidermis. These measurements were focused on documenting the effect of pectinase enzyme treatment. The results indicate a significant change in the V(z) signature curves with time into the enzyme treatment. Thus AFM and HF-SAM open the door to a systematic nondestructive structure and mechanical property

  7. Quantitative determination of 5-hydroxy-N-methylpyrrolidone in urine for biological monitoring of N-methylpyrrolidone exposure.

    Science.gov (United States)

    Ligocka, D; Lison, D; Haufroid, V

    2002-10-05

    The aim of this work was to validate a sensitive method for quantitative analysis of 5-hydroxy-N-methylpyrrolidone (5-HNMP) in urine. This compound has been recommended as a marker for biological monitoring of N-methylpyrrolidone (NMP) exposure. Different solvents and alternative methods of extraction including liquid-liquid extraction (LLE) on Chem Elut and solid-phase extraction (SPE) on Oasis HLB columns were tested. The most efficient extraction of 5-HNMP in urine was LLE with Chem Elut columns and dichloromethane as a solvent (consistently 22% of recovery). The urinary extracts were derivatized by bis(trimethylsilyl)trifluoroacetamide and analysed by gas chromatography-mass spectrometry (GC-MS) with tetradeutered 5-HNMP as an internal standard. The detection limit of this method is 0.017 mg/l urine with an intraassay precision of 1.6-2.6%. The proposed method of extraction is simple and reproducible. Four different m/z signal ratios of TMS-5-HNMP and tetralabelled TMS-5-HNMP have been validated and could be indifferently used in case of unexpected impurities from urine matrix. Copyright 2002 Elsevier Science B.V.

  8. Simulation of biological flow and transport in complex geometries using embedded boundary/volume-of-fluid methods

    International Nuclear Information System (INIS)

    Trebotich, David

    2007-01-01

    We have developed a simulation capability to model multiscale flow and transport in complex biological systems based on algorithms and software infrastructure developed under the SciDAC APDEC CET. The foundation of this work is a new hybrid fluid-particle method for modeling polymer fluids in irregular microscale geometries that enables long-time simulation of validation experiments. Both continuum viscoelastic and discrete particle representations have been used to model the constitutive behavior of polymer fluids. Complex flow environment geometries are represented on Cartesian grids using an implicit function. Direct simulation of flow in the irregular geometry is then possible using embedded boundary/volume-of-fluid methods without loss of geometric detail. This capability has been used to simulate biological flows in a variety of application geometries including biomedical microdevices, anatomical structures and porous media

  9. Feasibility of disposal of high-level radioactive waste into the seabed. Volume 6: Deep-sea biology, biological processes and radiobiology

    International Nuclear Information System (INIS)

    Pentreath, R.J.; Hargrave, B.T.; Roe, H.S.J.; Sibuet, M.

    1988-01-01

    One of the options suggested for disposal of high-level radioactive waste resulting from the generation of nuclear power is burial beneath the deep ocean floor in geologically stable sediment formations which have no economic value. The 8-volume series provides an assessment of the technical feasibility and radiological safety of this disposal concept based on the results obtained by ten years of co-operation and information exchange among the Member countries participating in the NEA Seabed Working Group. This report summarizes the biological description of selected sites, the means by which radionuclides could result in human exposure via seafood pathways, and the doses likely to be received by, and effects on, the deep-sea fauna

  10. Variability of left ventricular ejection fraction and volumes with quantitative gated SPECT: influence of algorithm, pixel size and reconstruction parameters in small and normal-sized hearts

    International Nuclear Information System (INIS)

    Hambye, Anne-Sophie; Vervaet, Ann; Dobbeleir, Andre

    2004-01-01

    Several software packages are commercially available for quantification of left ventricular ejection fraction (LVEF) and volumes from myocardial gated single-photon emission computed tomography (SPECT), all of which display a high reproducibility. However, their accuracy has been questioned in patients with a small heart. This study aimed to evaluate the performances of different software and the influence of modifications in acquisition or reconstruction parameters on LVEF and volume measurements, depending on the heart size. In 31 patients referred for gated SPECT, 64 2 and 128 2 matrix acquisitions were consecutively obtained. After reconstruction by filtered back-projection (Butterworth, 0.4, 0.5 or 0.6 cycles/cm cut-off, order 6), LVEF and volumes were computed with different software [three versions of Quantitative Gated SPECT (QGS), the Emory Cardiac Toolbox (ECT) and the Stanford University (SU-Segami) Medical School algorithm] and processing workstations. Depending upon their end-systolic volume (ESV), patients were classified into two groups: group I (ESV>30 ml, n=14) and group II (ESV 2 to 128 2 were associated with significantly larger volumes as well as lower LVEF values. Increasing the filter cut-off frequency had the same effect. With SU-Segami, a larger matrix was associated with larger end-diastolic volumes and smaller ESVs, resulting in a highly significant increase in LVEF. Increasing the filter sharpness, on the other hand, had no influence on LVEF though the measured volumes were significantly larger. (orig.)

  11. 'DRF-G - Grenoble Department of Fundamental Research. Activity report 1985, Nr 20. Volume II: 'Chemical Physics' 'Biology'

    International Nuclear Information System (INIS)

    1983-01-01

    This volume contains synthetic reports of researches performed in chemistry, in the field of biological and medical applications of nuclear magnetic resonance, and in biology during the 1981-1983 period or only during 1983. As far as chemistry is concerned, the following topics have been addressed: conducting organic polymers, organic and analytic electrochemistry, coordination chemistry, molecular dynamics, vegetal macromolecules, nucleic acids. As far as biology is concerned, the following topics have been addressed: systems associated with membranes, metalloproteins, cell biology and differentiation, immuno-chemistry, haematology, vegetal physiology, structural studies of proteins. Staff lists of researchers are provided for chemistry laboratories and biology laboratories, as well a list of publications

  12. Biological Survey, Buffalo River and Outer Harbor of Buffalo, New York. Volume I.

    Science.gov (United States)

    1982-06-01

    gizzard shad, pumpkin - seeds, rock bass, carp and golden shiner larvae were observed (Tables C1-C3, Volume 2). Figure 5 displays total seasonal...carp, pumpkin - seeds, yellow perch and gizzard shad scattered throughout the samples. From July through September, carp, pumpkinseeds and gizzard...cottonwoods to 9 m in height. In wet pockets, particularly east of the service road which parallels Fuhrmann Boulevard, Phragmites forms an almost pure

  13. Quantitative assessment of fatty infiltration and muscle volume of the rotator cuff muscles using 3-dimensional 2-point Dixon magnetic resonance imaging.

    Science.gov (United States)

    Matsumura, Noboru; Oguro, Sota; Okuda, Shigeo; Jinzaki, Masahiro; Matsumoto, Morio; Nakamura, Masaya; Nagura, Takeo

    2017-10-01

    In patients with rotator cuff tears, muscle degeneration is known to be a predictor of irreparable tears and poor outcomes after surgical repair. Fatty infiltration and volume of the whole muscles constituting the rotator cuff were quantitatively assessed using 3-dimensional 2-point Dixon magnetic resonance imaging. Ten shoulders with a partial-thickness tear, 10 shoulders with an isolated supraspinatus tear, and 10 shoulders with a massive tear involving supraspinatus and infraspinatus were compared with 10 control shoulders after matching age and sex. With segmentation of muscle boundaries, the fat fraction value and the volume of the whole rotator cuff muscles were computed. After reliabilities were determined, differences in fat fraction, muscle volume, and fat-free muscle volume were evaluated. Intra-rater and inter-rater reliabilities were regarded as excellent for fat fraction and muscle volume. Tendon rupture adversely increased the fat fraction value of the respective rotator cuff muscle (P tear group, muscle volume was significantly decreased in the infraspinatus (P = .035) and increased in the teres minor (P = .039). With subtraction of fat volume, a significant decrease of fat-free volume of the supraspinatus muscle became apparent with a massive tear (P = .003). Three-dimensional measurement could evaluate fatty infiltration and muscular volume with excellent reliabilities. The present study showed that chronic rupture of the tendon adversely increases the fat fraction of the respective muscle and indicates that the residual capacity of the rotator cuff muscles might be overestimated in patients with severe fatty infiltration. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  14. Increased brain iron deposition is a risk factor for brain atrophy in patients with haemodialysis: a combined study of quantitative susceptibility mapping and whole brain volume analysis.

    Science.gov (United States)

    Chai, Chao; Zhang, Mengjie; Long, Miaomiao; Chu, Zhiqiang; Wang, Tong; Wang, Lijun; Guo, Yu; Yan, Shuo; Haacke, E Mark; Shen, Wen; Xia, Shuang

    2015-08-01

    To explore the correlation between increased brain iron deposition and brain atrophy in patients with haemodialysis and their correlation with clinical biomarkers and neuropsychological test. Forty two patients with haemodialysis and forty one age- and gender-matched healthy controls were recruited in this prospective study. 3D whole brain high resolution T1WI and susceptibility weighted imaging were scanned on a 3 T MRI system. The brain volume was analyzed using voxel-based morphometry (VBM) in patients and to compare with that of healthy controls. Quantitative susceptibility mapping was used to measure and compare the susceptibility of different structures between patients and healthy controls. Correlation analysis was used to investigate the relationship between the brain volume, iron deposition and neuropsychological scores. Stepwise multiple regression analysis was used to explore the effect of clinical biomarkers on the brain volumes in patients. Compared with healthy controls, patients with haemodialysis showed decreased volume of bilateral putamen and left insular lobe (All P brain iron deposition is negatively correlated with the decreased volume of bilateral putamen (P brain iron deposition and dialysis duration was risk factors for brain atrophy in patients with haemodialysis. The decreased gray matter volume of the left insular lobe was correlated with neurocognitive impairment.

  15. A method for volume determination of the orbit and its contents by high resolution axial tomography and quantitative digital image analysis.

    Science.gov (United States)

    Cooper, W C

    1985-01-01

    The various congenital and acquired conditions which alter orbital volume are reviewed. Previous investigative work to determine orbital capacity is summarized. Since these studies were confined to postmortem evaluations, the need for a technique to measure orbital volume in the living state is presented. A method for volume determination of the orbit and its contents by high-resolution axial tomography and quantitative digital image analysis is reported. This procedure has proven to be accurate (the discrepancy between direct and computed measurements ranged from 0.2% to 4%) and reproducible (greater than 98%). The application of this method to representative clinical problems is presented and discussed. The establishment of a diagnostic system versatile enough to expand the usefulness of computerized axial tomography and polytomography should add a new dimension to ophthalmic investigation and treatment.

  16. Quantitative grain-scale ferroic domain volume fractions and domain switching strains from three-dimensional X-ray diffraction data

    DEFF Research Database (Denmark)

    Oddershede, Jette; Majkut, Marta; Caosyd, Qinghua

    2015-01-01

    A method for the extension of the three-dimensional X-ray diffraction technique to allow the extraction of domain volume fractions in polycrystalline ferroic materials is presented. This method gives access to quantitative domain volume fractions of hundreds of independent embedded grains within...... are applied to tetragonal coarse-grained Ba0.88Ca0.12Zr0.06Ti0.94O3 and rhombohedral fine-grained (0.82)Bi0.5Na0.5TiO3–(0.18)Bi0.5K0.5TiO3 electroceramic materials. The fitted volume fraction information is used to calculate grain-scale non-180° ferroelectric domain switching strains. The absolute errors...

  17. Cellular phone-based image acquisition and quantitative ratiometric method for detecting cocaine and benzoylecgonine for biological and forensic applications.

    Science.gov (United States)

    Cadle, Brian A; Rasmus, Kristin C; Varela, Juan A; Leverich, Leah S; O'Neill, Casey E; Bachtell, Ryan K; Cooper, Donald C

    2010-01-01

    Here we describe the first report of using low-cost cellular or web-based digital cameras to image and quantify standardized rapid immunoassay strips as a new point-of-care diagnostic and forensics tool with health applications. Quantitative ratiometric pixel density analysis (QRPDA) is an automated method requiring end-users to utilize inexpensive (∼ $1 USD/each) immunotest strips, a commonly available web or mobile phone camera or scanner, and internet or cellular service. A model is described whereby a central computer server and freely available IMAGEJ image analysis software records and analyzes the incoming image data with time-stamp and geo-tag information and performs the QRPDA using custom JAVA based macros (http://www.neurocloud.org). To demonstrate QRPDA we developed a standardized method using rapid immunotest strips directed against cocaine and its major metabolite, benzoylecgonine. Images from standardized samples were acquired using several devices, including a mobile phone camera, web cam, and scanner. We performed image analysis of three brands of commercially available dye-conjugated anti-cocaine/benzoylecgonine (COC/BE) antibody test strips in response to three different series of cocaine concentrations ranging from 0.1 to 300 ng/ml and BE concentrations ranging from 0.003 to 0.1 ng/ml. This data was then used to create standard curves to allow quantification of COC/BE in biological samples. Across all devices, QRPDA quantification of COC and BE proved to be a sensitive, economical, and faster alternative to more costly methods, such as gas chromatography-mass spectrometry, tandem mass spectrometry, or high pressure liquid chromatography. The limit of detection was determined to be between 0.1 and 5 ng/ml. To simulate conditions in the field, QRPDA was found to be robust under a variety of image acquisition and testing conditions that varied temperature, lighting, resolution, magnification and concentrations of biological fluid in a sample. To

  18. Cellular Phone-Based Image Acquisition and Quantitative Ratiometric Method for Detecting Cocaine and Benzoylecgonine for Biological and Forensic Applications

    Directory of Open Access Journals (Sweden)

    Brian A. Cadle

    2010-01-01

    Full Text Available Here we describe the first report of using low-cost cellular or web-based digital cameras to image and quantify standardized rapid immunoassay strips as a new point-of-care diagnostic and forensics tool with health applications. Quantitative ratiometric pixel density analysis (QRPDA is an automated method requiring end-users to utilize inexpensive (~ $1 USD/each immunotest strips, a commonly available web or mobile phone camera or scanner, and internet or cellular service. A model is described whereby a central computer server and freely available IMAGEJ image analysis software records and analyzes the incoming image data with time-stamp and geo-tag information and performs the QRPDA using custom JAVA based macros ( http://www.neurocloud.org . To demonstrate QRPDA we developed a standardized method using rapid immunotest strips directed against cocaine and its major metabolite, benzoylecgonine. Images from standardized samples were acquired using several devices, including a mobile phone camera, web cam, and scanner. We performed image analysis of three brands of commercially available dye-conjugated anti-cocaine/benzoylecgonine (COC/BE antibody test strips in response to three different series of cocaine concentrations ranging from 0.1 to 300 ng/ml and BE concentrations ranging from 0.003 to 0.1 ng/ml. This data was then used to create standard curves to allow quantification of COC/BE in biological samples. Across all devices, QRPDA quantification of COC and BE proved to be a sensitive, economical, and faster alternative to more costly methods, such as gas chromatography-mass spectrometry, tandem mass spectrometry, or high pressure liquid chromatography. The limit of detection was determined to be between 0.1 and 5 ng/ml. To simulate conditions in the field, QRPDA was found to be robust under a variety of image acquisition and testing conditions that varied temperature, lighting, resolution, magnification and concentrations of biological fluid

  19. Quantitative assessment of the synovial membrane in the rheumatoid wrist: an easily obtained MRI score reflects the synovial volume

    DEFF Research Database (Denmark)

    Østergaard, Mikkel; Hansen, M; Stoltenberg, M

    1996-01-01

    Determination of the synovial membrane volume in the rheumatoid arthritis (RA) wrist by gadolinium-DTPA-enhanced MRI is introduced. Moreover, dynamic imaging and an MRI score of synovial hypertrophy, based on gradings in six regions, are evaluated as substitutes of the time-consuming volume...

  20. Three-dimensional volume rendering of tibiofibular joint space and quantitative analysis of change in volume due to tibiofibular syndesmosis diastases

    International Nuclear Information System (INIS)

    Taser, F.; Shafiq, Q.; Ebraheim, N.A.

    2006-01-01

    The diagnosis of ankle syndesmosis injuries is made by various imaging techniques. The present study was undertaken to examine whether the three-dimensional reconstruction of axial CT images and calculation of the volume of tibiofibular joint space enhances the sensitivity of diastases diagnoses or not. Six adult cadaveric ankle specimens were used for spiral CT-scan assessment of tibiofibular syndesmosis. After the specimens were dissected, external fixation was performed and diastases of 1, 2, and 3 mm was simulated by a precalibrated device. Helical CT scans were obtained with 1.0-mm slice thickness. The data was transferred to the computer software AcquariusNET. Then the contours of the tibiofibular syndesmosis joint space were outlined on each axial CT slice and the collection of these slices were stacked using the computer software AutoCAD 2005, according to the spatial arrangement and geometrical coordinates between each slice, to produce a three-dimensional reconstruction of the joint space. The area of each slice and the volume of the entire tibiofibular joint space were calculated. The tibiofibular joint space at the 10th-mm slice level was also measured on axial CT scan images at normal, 1, 2 and 3-mm joint space diastases. The three-dimensional volume-rendering of the tibiofibular syndesmosis joint space from the spiral CT data demonstrated the shape of the joint space and has been found to be a sensitive method for calculating joint space volume. We found that, from normal to 1 mm, a 1-mm diastasis increases approximately 43% of the joint space volume, while from 1 to 3 mm, there is about a 20% increase for each 1-mm increase. Volume calculation using this method can be performed in cases of syndesmotic instability after ankle injuries and for preoperative and postoperative evaluation of the integrity of the tibiofibular syndesmosis. (orig.)

  1. A Quantitative Analysis of the Relationship between Medicare Payment and Service Volume for Glaucoma Procedures from 2005 through 2009.

    Science.gov (United States)

    Gong, Dan; Jun, Lin; Tsai, James C

    2015-05-01

    To calculate the association between Medicare payment and service volume for 6 commonly performed glaucoma procedures. Retrospective, longitudinal database study. A 100% dataset of all glaucoma procedures performed on Medicare Part B beneficiaries within the United States from 2005 to 2009. Fixed-effects regression model using Medicare Part B carrier data for all 50 states and the District of Columbia, controlling for time-invariant carrier-specific characteristics, national trends in glaucoma service volume, Medicare beneficiary population, number of ophthalmologists, and income per capita. Payment-volume elasticities, defined as the percent change in service volume per 1% change in Medicare payment, for laser trabeculoplasty (Current Procedural Terminology [CPT] code 65855), trabeculectomy without previous surgery (CPT code 66170), trabeculectomy with previous surgery (CPT code 66172), aqueous shunt to reservoir (CPT code 66180), laser iridotomy (CPT code 66761), and scleral reinforcement with graft (CPT code 67255). The payment-volume elasticity was nonsignificant for 4 of 6 procedures studied: laser trabeculoplasty (elasticity, -0.27; 95% confidence interval [CI], -1.31 to 0.77; P = 0.61), trabeculectomy without previous surgery (elasticity, -0.42; 95% CI, -0.85 to 0.01; P = 0.053), trabeculectomy with previous surgery (elasticity, -0.28; 95% CI, -0.83 to 0.28; P = 0.32), and aqueous shunt to reservoir (elasticity, -0.47; 95% CI, -3.32 to 2.37; P = 0.74). Two procedures yielded significant associations between Medicare payment and service volume. For laser iridotomy, the payment-volume elasticity was -1.06 (95% CI, -1.39 to -0.72; P payment, laser iridotomy service volume increased by 1.06%. For scleral reinforcement with graft, the payment-volume elasticity was -2.92 (95% CI, -5.72 to -0.12; P = 0.041): for every 1% decrease in CPT code 67255 payment, scleral reinforcement with graft service volume increased by 2.92%. This study calculated the association

  2. Quantitative estimation of a ratio of intracranial cerebrospinal fluid volume to brain volume based on segmentation of CT images in patients with extra-axial hematoma.

    Science.gov (United States)

    Nguyen, Ha Son; Patel, Mohit; Li, Luyuan; Kurpad, Shekar; Mueller, Wade

    2017-02-01

    Background Diminishing volume of intracranial cerebrospinal fluid (CSF) in patients with space-occupying masses have been attributed to unfavorable outcome associated with reduction of cerebral perfusion pressure and subsequent brain ischemia. Objective The objective of this article is to employ a ratio of CSF volume to brain volume for longitudinal assessment of space-volume relationships in patients with extra-axial hematoma and to determine variability of the ratio among patients with different types and stages of hematoma. Patients and methods In our retrospective study, we reviewed 113 patients with surgical extra-axial hematomas. We included 28 patients (age 61.7 +/- 17.7 years; 19 males, nine females) with an acute epidural hematoma (EDH) ( n = 5) and subacute/chronic subdural hematoma (SDH) ( n = 23). We excluded 85 patients, in order, due to acute SDH ( n = 76), concurrent intraparenchymal pathology ( n = 6), and bilateral pathology ( n = 3). Noncontrast CT images of the head were obtained using a CT scanner (2004 GE LightSpeed VCT CT system, tube voltage 140 kVp, tube current 310 mA, 5 mm section thickness) preoperatively, postoperatively (3.8 ± 5.8 hours from surgery), and at follow-up clinic visit (48.2 ± 27.7 days after surgery). Each CT scan was loaded into an OsiriX (Pixmeo, Switzerland) workstation to segment pixels based on radiodensity properties measured in Hounsfield units (HU). Based on HU values from -30 to 100, brain, CSF spaces, vascular structures, hematoma, and/or postsurgical fluid were segregated from bony structures, and subsequently hematoma and/or postsurgical fluid were manually selected and removed from the images. The remaining images represented overall brain volume-containing only CSF spaces, vascular structures, and brain parenchyma. Thereafter, the ratio between the total number of voxels representing CSF volume (based on values between 0 and 15 HU) to the total number of voxels

  3. Quantitatively Measured Anatomic Location and Volume of Optic Disc Drusen: An Enhanced Depth Imaging Optical Coherence Tomography Study

    DEFF Research Database (Denmark)

    Malmqvist, Lasse; Lindberg, Anne-Sofie Wessel; Dahl, Vedrana Andersen

    2017-01-01

    function using automated perimetric mean deviation (MD) and multifocal visual evoked potentials. Increased age (P = 0.015); larger ODD volume (P = 0.002); and more superficial anatomic ODD location (P = 0.007) were found in patients with ODD visible by ophthalmoscopy compared to patients with buried ODD.......025) and had a higher effect on MD when compared to retinal nerve fiber layer thickness. Large ODD volume is associated with optic nerve dysfunction. The worse visual field defects associated with visible ODD should only be ascribed to larger ODD volume and not to a more superficial anatomic ODD location....

  4. A newly developed maneuver, field change conversion (FCC), improved evaluation of the left ventricular volume more accurately on quantitative gated SPECT (QGS) analysis

    International Nuclear Information System (INIS)

    Tajima, Osamu; Shibasaki, Masaki; Hoshi, Toshiko; Imai, Kamon

    2002-01-01

    The purpose of this study was to investigate whether a newly developed maneuver that reduces the reconstruction area by a half more accurately evaluates left ventricular (LV) volume on quantitative gated SPECT (QGS) analysis. The subjects were 38 patients who underwent left ventricular angiography (LVG) followed by G-SPECT within 2 weeks. Acquisition was performed with a general purpose collimator and a 64 x 64 matrix. On QGS analysis, the field magnification was 34 cm in original image (Original: ORI), and furthermore it was changed from 34 cm to 17 cm to enlarge the re-constructed image (Field Change Conversion: FCC). End-diastolic volume (EDV) and end-systolic volume (ESV) of the left ventricle were also obtained using LVG. EDV was 71±19 ml, 83±20 ml and 98±23 ml for ORI, FCC and LVG, respectively (p<0.001: ORI versus LVG, p<0.001: ORI versus FCC, p<0.001: FCC versus LVG). ESV was 28±12 ml, 34±13 ml and 41±14 ml for ORI, FCC and LVG, respectively (p<0.001: ORI versus LVG, p<0.001: ORI versus FCC, p<0.001: FCC versus LVG). FCC was better than ORI for calculating LV volume in clinical cases. Furthermore, FCC is a useful method for accurately measuring the LV volume on QGS analysis. (author)

  5. Volume Tracking: A new method for quantitative assessment and visualization of intracardiac blood flow from three-dimensional, time-resolved, three-component magnetic resonance velocity mapping

    Directory of Open Access Journals (Sweden)

    Arheden Håkan

    2011-04-01

    Full Text Available Abstract Background Functional and morphological changes of the heart influence blood flow patterns. Therefore, flow patterns may carry diagnostic and prognostic information. Three-dimensional, time-resolved, three-directional phase contrast cardiovascular magnetic resonance (4D PC-CMR can image flow patterns with unique detail, and using new flow visualization methods may lead to new insights. The aim of this study is to present and validate a novel visualization method with a quantitative potential for blood flow from 4D PC-CMR, called Volume Tracking, and investigate if Volume Tracking complements particle tracing, the most common visualization method used today. Methods Eight healthy volunteers and one patient with a large apical left ventricular aneurysm underwent 4D PC-CMR flow imaging of the whole heart. Volume Tracking and particle tracing visualizations were compared visually side-by-side in a visualization software package. To validate Volume Tracking, the number of particle traces that agreed with the Volume Tracking visualizations was counted and expressed as a percentage of total released particles in mid-diastole and end-diastole respectively. Two independent observers described blood flow patterns in the left ventricle using Volume Tracking visualizations. Results Volume Tracking was feasible in all eight healthy volunteers and in the patient. Visually, Volume Tracking and particle tracing are complementary methods, showing different aspects of the flow. When validated against particle tracing, on average 90.5% and 87.8% of the particles agreed with the Volume Tracking surface in mid-diastole and end-diastole respectively. Inflow patterns in the left ventricle varied between the subjects, with excellent agreement between observers. The left ventricular inflow pattern in the patient differed from the healthy subjects. Conclusion Volume Tracking is a new visualization method for blood flow measured by 4D PC-CMR. Volume Tracking

  6. Optimization of total arc degree for stereotactic radiotherapy by using integral biologically effective dose and irradiated volume

    International Nuclear Information System (INIS)

    Lim, Do Hoon; Kim, Dae Yong; Lee, Myung Za; Chun, Ha Chung

    2001-01-01

    To find the optimal values of total arc degree to protect the normal brain tissue from high dose radiation in stereotactic radiotherapy planning. With Xknife-3 planning system and 4 MV linear accelerator, the authors planned under various values of parameters. One isocenter, 12, 20, 30, 40, 50, and 60 mm of collimator diameters, 100 deg, 200 deg, 300 deg, 400 deg, 500 deg, 600 deg, of total arc degrees, and 30 deg or 45 deg of arc intervals were used. After the completion of planning, the plans were compared each other using V 50 (the volume of normal brain that is delivered high dose radiation) and integral biologically effective dose. At 30 deg of arc interval, the values of V 50 had the decreased pattern with the increase of total arc degree in any collimator diameter. At 45 deg arc interval, up to 400 deg of total arc degree, the values of V 50 decreased with the increase of total arc degree, but at 500 deg and 600 deg of total arc degrees, the values increased. At 30 deg of arc interval, integral biologically effective dose showed the decreased pattern with the increase of total arc degree in any collimator diameter. At 45 deg arc interval with less than 40 mm collimator diameter, the integral biologically effective dose decreased with the increase of total arc degree, but with 50 and 60 mm of collimator diameters, up to 400 deg of total arc degree, integral biologically effective dose decreased with the increase of total arc degree, but at 500 deg and 600 deg of total arc degrees, the values increased. In the stereotactic radiotherapy planning for brain lesions, planning with 400 deg of total arc degree is optimal. Especially, when the larger collimator more than 50 mm diameter should be used, the uses of 500 deg and 600 deg of total arc degrees make the increase of V 50 and integral biologically effective dose, Therefore stereotactic radiotherapy planning using 400 deg of total arc degree can increase the therapeutic ratio and produce the effective outcome

  7. Gender differences in knee joint cartilage thickness, volume and articular surface areas: assessment with quantitative three-dimensional MR imaging

    International Nuclear Information System (INIS)

    Faber, S.C.; Reiser, M.; Englmeier, K.H.

    2001-01-01

    Objective: To compare the cartilage thickness, volume, and articular surface areas of the knee joint between young healthy, non-athletic female and male individuals. Subjects and design. MR imaging was performed in 18 healthy subjects without local or systemic joints disease (9 female, age 22.3±2.4 years, and 9 male, age 22.2.±1.9 years), using a fat-suppressed FLASH 3D pulse sequence (TR=41 ms, TE=11 ms, FA=30 ) with sagittal orientation and a spatial resolution of 2x0.31x0.31 mm 3 . After three-dimensional reconstruction and triangulation of the knee joint cartilage plates, the cartilage thickness (mean and maximal), volume, and size of the articular surface area were quantified, independent of the original section orientation. Results and conclusions: Women displayed smaller cartilage volumes than men, the percentage difference ranging from 19.9% in the patella, to 46.6% in the medial tibia. The gender differences of the cartilage thickness were smaller, ranging from 2.0% in the femoral trochlea to 13.3% in the medial tibia for the mean thickness, and from 4.3% in the medial femoral condyle to 18.3% in the medial tibia for the maximal cartilage thickness. The differences between the cartilage surface areas were similar to those of the volumes, with values ranging from 21.0% in the femur to 33.4% in the lateral tibia. Gender differences could be reduced for cartilage volume and surface area when normalized to body weight and body weight x body height. The study demonstrates significant gender differences in cartilage volume and surface area of men and women, which need to be taken into account when retrospectively estimating articular cartilage loss in patients with symptoms of degenerative joint disease. Differences in cartilage volume are primarily due to differences in joint surface areas (epiphyseal bone size), not to differences in cartilage thickness. (orig.)

  8. PERFORMANSI BIOLOGIS CALON INDUK PATIN JAMBAL (Pangasius djambal PADA VOLUME BAK DAN CARA AERASI BERBEDA

    Directory of Open Access Journals (Sweden)

    Taufik Ahmad

    2016-12-01

    Patin jambal is one of Indonesia indigenous species which is threatened to extinction in Java open water due to development progress as well as over fishing. Further mass production of patin jambal seeds in hatchery faces the unsustainable supply of spawner. Tank size and aeration technique are suspected to affect patin jambal spawner production in captivity since the fish is a riverine species. The experiment aims at providing a suitable environment for such a fish to grow to be productive spawners. Four circular concrete tanks are used to assure maximum water circulation; two tanks were filled with 10 m3 and the other with 20 m3 fresh surface water at equal depth, 130 cm. The surface water was gravitationally flowed from the surface into 2 tanks and from the bottom into 2 other tanks at 0.6-1.0 L sec-1. The fish weighted 1.5 kg each was stocked at 7 female and 3 male into each of 10 m3 tank and at 15 females and 5 males into each of 20 m3 tank.  The experimental units were arranged in a completely randomized design with pseudo replication. The fish fed commercial artificial diet at 3% of biomass weight a day. Fish in the 20 m3 tank equipped with bottom water inlet gained weight 0.601 % day-1 and consequently grew faster (P<0.05 than fish in the other tanks.  Fish in the same tank was also biologically mature faster than fish in the other tanks; four males and one male were found to reach gonad maturity stage IV which was not found in the other tanks. Obviously, a 20 m3 concrete tank equipped with bottom water inlet is suitable for patin jambal spawner production at 15 females to 5 males ratio.

  9. Stereological estimation of nuclear volume and other quantitative histopathological parameters in the prognostic evaluation of supraglottic laryngeal squamous cell carcinoma

    DEFF Research Database (Denmark)

    Sørensen, Flemming Brandt; Bennedbaek, O; Pilgaard, J

    1989-01-01

    The aim of this study was to investigate various approaches to the grading of malignancy in pre-treatment biopsies from patients with supraglottic laryngeal squamous cell carcinoma. The prospects of objective malignancy grading based on stereological estimation of the volume-weighted mean nuclear...... volume, nuclear Vv, and nuclear volume fraction, Vv(nuc/tis), along with morphometrical 2-dimensional estimation of nuclear density index, NI, and mitotic activity index, MI, were investigated and compared with the current morphological, multifactorial grading system. The reproducibility among two...... observers of the latter was poor in the material which consisted of 35 biopsy specimens. Unbiased estimates of nuclear Vv were on the average 385 microns3 (CV = 0.44), with more than 90% of the associated variance attributable to differences in nuclear Vv among individual lesions. Nuclear Vv was positively...

  10. Quantitative Magnetic Resonance Imaging of Brainstem Volumes, Plaques, and Surface Area in the Occipital Regions of Patients with Multiple Sclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Alper, F.; Kantarci, M.; Altunkaynak, E.; Varoglu, A. O.; Karaman, A.; Oral, E.; Okur, A. [Ataturk Univ., Erzurum (Turkey). Depts. of Radiology, Histology, Neurology and Embryology, Psychiatry

    2006-07-15

    Purpose: To determine brainstem volumes, number of plaques, and surface areas in the occipital lobes of patients with relapsing remitting multiple sclerosis (RRMS) and secondary progressive multiple sclerosis (SPMS), and to investigate whether there is any correlation between brainstem volume and the number/surface areas of plaque in the occipital lobes. Material and Methods: Magnetic resonance imaging was obtained on 14 relapsing-remitting (RR) and 13 secondary progressive (SP) MS patients and 26 female control subjects. The Cavalieri method was used by modern design stereology to measure brainstem volume. The point-counting grid was used to evaluate sclerotic plaque surface areas in the occipital lobe. The number of plaques in the imaging section was calculated. Results: Brainstem volumes for RR and SP with multiple sclerosis and control subjects were 3647 mm{sup 3} , 3515 mm{sup 3} , and 4517 mm{sup 3} , respectively. Mean number of plaques in the right-left occipital lobe was found to be 2.7-3.4 in RR-MS and 5.2-2.8 in SP-MS. Mean plaque surface area in the right-left occipital lobe was determined to be 58.52-88.24 mm{sup 2} in RR MS and 124.3-64.82 mm{sup 2} in SP MS. Brainstem volumes were significantly reduced in both groups of patients with MS compared to controls ( P <0.01). Conclusion: Magnetic-resonance-estimated volume and surface area values in multiple sclerosis may facilitate our understanding of the clinical situation of patients and provide a simple index for evaluating therapeutic efficiency.

  11. Quantitative Magnetic Resonance Imaging of Brainstem Volumes, Plaques, and Surface Area in the Occipital Regions of Patients with Multiple Sclerosis

    International Nuclear Information System (INIS)

    Alper, F.; Kantarci, M.; Altunkaynak, E.; Varoglu, A. O.; Karaman, A.; Oral, E.; Okur, A.

    2006-01-01

    Purpose: To determine brainstem volumes, number of plaques, and surface areas in the occipital lobes of patients with relapsing remitting multiple sclerosis (RRMS) and secondary progressive multiple sclerosis (SPMS), and to investigate whether there is any correlation between brainstem volume and the number/surface areas of plaque in the occipital lobes. Material and Methods: Magnetic resonance imaging was obtained on 14 relapsing-remitting (RR) and 13 secondary progressive (SP) MS patients and 26 female control subjects. The Cavalieri method was used by modern design stereology to measure brainstem volume. The point-counting grid was used to evaluate sclerotic plaque surface areas in the occipital lobe. The number of plaques in the imaging section was calculated. Results: Brainstem volumes for RR and SP with multiple sclerosis and control subjects were 3647 mm 3 , 3515 mm 3 , and 4517 mm 3 , respectively. Mean number of plaques in the right-left occipital lobe was found to be 2.7-3.4 in RR-MS and 5.2-2.8 in SP-MS. Mean plaque surface area in the right-left occipital lobe was determined to be 58.52-88.24 mm 2 in RR MS and 124.3-64.82 mm 2 in SP MS. Brainstem volumes were significantly reduced in both groups of patients with MS compared to controls ( P <0.01). Conclusion: Magnetic-resonance-estimated volume and surface area values in multiple sclerosis may facilitate our understanding of the clinical situation of patients and provide a simple index for evaluating therapeutic efficiency

  12. Normalization in quantitative [18F]FDG PET imaging: the 'body surface area' may be a volume

    International Nuclear Information System (INIS)

    Laffon, Eric; Suarez, Kleydis; Berthoumieu, Yannick; Ducassou, Dominique; Marthan, Roger

    2006-01-01

    Non-invasive methods for quantifying [ 18 F]FDG uptake in tumours often require normalization to either body weight or body surface area (BSA), as a surrogate for [ 18 F]FDG distribution volume (DV). Whereas three dimensions are involved in DV and weight (assuming that weight is proportional to volume), only two dimensions are obviously involved in BSA. However, a fractal geometry interpretation, related to an allometric scaling, suggests that the so-called 'body surface area' may stand for DV. (note)

  13. Assessment of pulmonary vasculature volume with automated threshold-based 3D quantitative CT volumetry: In vitro and in vivo validation

    International Nuclear Information System (INIS)

    Liu Jingzhe; Wu Qingyu; Xu Yufeng; Bai Yan; Liu Zhibo; Li Hongyin; Zhu Jiemin

    2012-01-01

    Objectives: To validate the ability of threshold-based 3D CT volumetry to enable measurement of volume of visible pulmonary vessels on CT. Materials and methods: In vivo, 3D CT volumetry was validated in seven phantoms that consisted of silicone tubes embedded in a foam block. With the true volume value as reference standard, the accuracy of CT measurement at various lower thresholds of −600 HU, −500 HU, −300 HU and −200 HU were compared. The volume measurements obtained when filled with varied concentration of iodinated contrast media (1:100, 1:200 and 1:500) were also compared. In vivo validation was performed in sixteen patients (9 men, 7 women; mean age, 52.1 years). Inter-scan and inter-observer agreement and reproducibility for pulmonary vasculature volume measurement were evaluated with Bland–Altman analysis. Results: In vitro, the mean value measured under lower threshold of −300 HU (relative error = 1.5%) were the closest to the true values and have no significant difference (P = 0.375). There were no significant differences among the phantom measurement values with different filled concentration (1:100, 1:200 and 1:500). In vivo, the inter-scan reproducibility of volume measurements was good, with a correlation coefficient of 0.82 and ICC (intraclass correlation coefficient) of 0.86. Inter-observer agreement was excellent with a correlation coefficient of 0.91 and ICC of 0.95. Conclusions: The threshold-based 3D quantitative CT volumetry enables accurate and reproducible measurement of pulmonary vessels volume.

  14. Molecular image-guided radiation treatment planing using biological target volume (BTV)for advanced esophageal cancer

    International Nuclear Information System (INIS)

    Tamamura, Hiroyasu; Sasaki, Makoto; Bou, Sayuri; Satou, Yoshitaka; Minami, Hiroki; Saga, Yusuke; Aoyama, Masashi; Yamamoto, Kazutaka; Kawamura, Mariko

    2016-01-01

    As the biological mechanisms of cancer cell proliferation become clear at molecular level, 'precision therapy' is attracting a great attention, in which the irradiation dose and area are determined in consideration of these molecular mechanism. For this sophisticated radiotherapy, it is essential to evaluate the tumor morphology and proliferation/activation of cancer cells before radiation treatment planning. Generally, cancer cells start to proliferate when their activity levels increase, and subsequently primary tumor or metastatic tumor that can De recognized by CT scan or MRI start to develop. Thus, when proliferation of cancer cells occurs and tumor start to develop, a vast amount of energy is required for proliferation and cancer cells obtain a part of this energy from glucose in the body. Therefore, we can get the information on the status of metabolism and density of cancer cells by PET using F-18-FDG, which is structurally similar to glucose. It is a general belief that, when conducting evaluation using F18-FDG-PET, evaluation of proliferation of cancer cells before tumor formation might be possible at the cell level by evaluating and visualizing glucose metabolism in cancer cells that proliferate in a manner that they cannot be visualized morphologically by using CT scan or MRI. Therefore, when performing sophisticated precision radiotherapy, it is important to implement radiation treatment plan including information obtained from FDG-PET imaging. Many studies have reported usefulness of FDG-PET imaging for esophagus cancer so far, indicating the efficacy of using FDG-PET imaging for radiation treatment plan of esophagus cancer as well. However, few studies have described how to use FDG-PET imaging for radiation treatment plan for esophagus cancer. In this review, therefore, we will outline the usefulness of molecular image-guided radiation treatment plan, in which biological target volume (BTV) and the actual radiation treatment plan using FDG

  15. Prognostic value of pretreatment volume-based quantitative {sup 18}F-FDG PET/CT parameters in patients with malignant pleural mesothelioma

    Energy Technology Data Exchange (ETDEWEB)

    Kitajima, Kazuhiro, E-mail: kitajima@med.kobe-u.ac.jp [Division of Nuclear Medicine and PET Center, Department of Radiology, Hyogo College of Medicine, Hyogo (Japan); Doi, Hiroshi, E-mail: h-doi@hyo-med.ac.jp [Department of Radiology, Hyogo College of Medicine, Hyogo (Japan); Kuribayashi, Kozo, E-mail: kuririn@hyo-med.ac.jp [Division of Respiratory Medicine, Department of Internal Medicine, Hyogo College of Medicine, Hyogo (Japan); Hashimoto, Masaki, E-mail: kogekogemasaki@gmail.com [Department of Thoracic Surgery, Hyogo College of Medicine, Hyogo (Japan); Tsuchitani, Tatsuya, E-mail: tty-823@hyo-med.ac.jp [Department of Radiological Technology, Hyogo College of Medicine College Hospital, Hyogo (Japan); Tanooka, Masao, E-mail: masao1108@gmail.com [Department of Radiological Technology, Hyogo College of Medicine College Hospital, Hyogo (Japan); Fukushima, Kazuhito, E-mail: fukuchan00106@gmail.com [Division of Nuclear Medicine and PET Center, Department of Radiology, Hyogo College of Medicine, Hyogo (Japan); Nakano, Takashi, E-mail: t-nakano@hyo-med.ac.jp [Division of Respiratory Medicine, Department of Internal Medicine, Hyogo College of Medicine, Hyogo (Japan); Hasegawa, Seiki, E-mail: hasegawa@hyo-med.ac.jp [Department of Thoracic Surgery, Hyogo College of Medicine, Hyogo (Japan); Hirota, Shozo, E-mail: hirota-s@hyo-med.ac.jp [Department of Radiology, Hyogo College of Medicine, Hyogo (Japan)

    2017-01-15

    Purpose: To investigate the relationships between pretreatment volume-based quantitative {sup 18}F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) parameters and overall survival (OS) in patients with malignant pleural mesothelioma (MPM). Materials and methods: We retrospectively reviewed data from 201 MPM patients, of whom 38 underwent surgical resection, and calculated the maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG), including primary tumors and nodal or distant metastatic lesions, on pretreatment {sup 18}F-FDG PET/CT. Relationships between clinicopathological factors (age, sex, performance status, European Organization for Research and Treatment of Cancer [EORTC] score, histological subtype, TNM stage, and treatment strategy), volume-based quantitative PET/CT parameters, and OS were evaluated using a Cox proportional hazards model and log-rank test. Results: The median follow-up was 15 months (range, 1–96 months; median, 17 months). In a univariate analysis of all patients, older age (p < 0.05), high EORTC score (p < 0.001), non-epithelioid histological subtype (p < 0.001), high T stage (p < 0.001), positive N/M status (p < 0.05, p < 0.001), advanced TNM stage (p < 0.001), non-surgical treatment (p < 0.001), and high SUVmax (p < 0.001), MTV (p < 0.001), or TLG (p < 0.001) were associated with significantly shorter OS. A multivariate analysis confirmed non-epithelioid subtype (hazard ratio [HR]: 1.69, 95% confidence interval [CI]: 1.14–2.48; p < 0.05), non-surgical treatment (HR: 0.58, 95% CI: 0.34–0.95; p < 0.05), and high TLG (HR: 1.97, 95% CI: 1.14–3.44; p < 0.05) as independent negative predictors. Conclusions: Pretreatment volume-based quantitative {sup 18}F-FDG PET/CT parameters, especially TLG, could serve as potential surrogate markers for MPM prognosis.

  16. Prognostic value of pretreatment volume-based quantitative 18F-FDG PET/CT parameters in patients with malignant pleural mesothelioma

    International Nuclear Information System (INIS)

    Kitajima, Kazuhiro; Doi, Hiroshi; Kuribayashi, Kozo; Hashimoto, Masaki; Tsuchitani, Tatsuya; Tanooka, Masao; Fukushima, Kazuhito; Nakano, Takashi; Hasegawa, Seiki; Hirota, Shozo

    2017-01-01

    Purpose: To investigate the relationships between pretreatment volume-based quantitative 18 F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) parameters and overall survival (OS) in patients with malignant pleural mesothelioma (MPM). Materials and methods: We retrospectively reviewed data from 201 MPM patients, of whom 38 underwent surgical resection, and calculated the maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG), including primary tumors and nodal or distant metastatic lesions, on pretreatment 18 F-FDG PET/CT. Relationships between clinicopathological factors (age, sex, performance status, European Organization for Research and Treatment of Cancer [EORTC] score, histological subtype, TNM stage, and treatment strategy), volume-based quantitative PET/CT parameters, and OS were evaluated using a Cox proportional hazards model and log-rank test. Results: The median follow-up was 15 months (range, 1–96 months; median, 17 months). In a univariate analysis of all patients, older age (p < 0.05), high EORTC score (p < 0.001), non-epithelioid histological subtype (p < 0.001), high T stage (p < 0.001), positive N/M status (p < 0.05, p < 0.001), advanced TNM stage (p < 0.001), non-surgical treatment (p < 0.001), and high SUVmax (p < 0.001), MTV (p < 0.001), or TLG (p < 0.001) were associated with significantly shorter OS. A multivariate analysis confirmed non-epithelioid subtype (hazard ratio [HR]: 1.69, 95% confidence interval [CI]: 1.14–2.48; p < 0.05), non-surgical treatment (HR: 0.58, 95% CI: 0.34–0.95; p < 0.05), and high TLG (HR: 1.97, 95% CI: 1.14–3.44; p < 0.05) as independent negative predictors. Conclusions: Pretreatment volume-based quantitative 18 F-FDG PET/CT parameters, especially TLG, could serve as potential surrogate markers for MPM prognosis.

  17. EFSA Panel on Biological Hazards; Scientific Opinion on a Quantitative Microbiological Risk Assessment of Salmonella in slaughter and breeder pigs

    DEFF Research Database (Denmark)

    Hald, Tine

    This Quantitative Microbiological Risk Assessment (QMRA) represents a major step forward in terms of modelling Salmonella in pigs from farm to consumption as it takes into account the variability between and within EU Member States (MSs). Around 10-20% of human Salmonella infections in EU may...

  18. A Novel HPLC Method for the Concurrent Analysis and Quantitation of Seven Water-Soluble Vitamins in Biological Fluids (Plasma and Urine: A Validation Study and Application

    Directory of Open Access Journals (Sweden)

    Margherita Grotzkyj Giorgi

    2012-01-01

    Full Text Available An HPLC method was developed and validated for the concurrent detection and quantitation of seven water-soluble vitamins (C, B1, B2, B5, B6, B9, B12 in biological matrices (plasma and urine. Separation was achieved at 30°C on a reversed-phase C18-A column using combined isocratic and linear gradient elution with a mobile phase consisting of 0.01% TFA aqueous and 100% methanol. Total run time was 35 minutes. Detection was performed with diode array set at 280 nm. Each vitamin was quantitatively determined at its maximum wavelength. Spectral comparison was used for peak identification in real samples (24 plasma and urine samples from abstinent alcohol-dependent males. Interday and intraday precision were <4% and <7%, respectively, for all vitamins. Recovery percentages ranged from 93% to 100%.

  19. A novel HPLC method for the concurrent analysis and quantitation of seven water-soluble vitamins in biological fluids (plasma and urine): a validation study and application.

    Science.gov (United States)

    Giorgi, Margherita Grotzkyj; Howland, Kevin; Martin, Colin; Bonner, Adrian B

    2012-01-01

    An HPLC method was developed and validated for the concurrent detection and quantitation of seven water-soluble vitamins (C, B(1), B(2), B(5), B(6), B(9), B(12)) in biological matrices (plasma and urine). Separation was achieved at 30°C on a reversed-phase C18-A column using combined isocratic and linear gradient elution with a mobile phase consisting of 0.01% TFA aqueous and 100% methanol. Total run time was 35 minutes. Detection was performed with diode array set at 280 nm. Each vitamin was quantitatively determined at its maximum wavelength. Spectral comparison was used for peak identification in real samples (24 plasma and urine samples from abstinent alcohol-dependent males). Interday and intraday precision were vitamins. Recovery percentages ranged from 93% to 100%.

  20. Improvements in the Quantitative Assessment of Cerebral Blood Volume and Flow with the Removal of Vessel Voxels from MR Perfusion Images

    Directory of Open Access Journals (Sweden)

    Michael Mu Huo Teng

    2013-01-01

    Full Text Available Objective. To improve the quantitative assessment of cerebral blood volume (CBV and flow (CBF in the brain voxels from MR perfusion images. Materials and Methods. Normal brain parenchyma was automatically segmented with the time-to-peak criteria after cerebrospinal fluid removal and preliminary vessel voxel removal. Two scaling factors were calculated by comparing the relative CBV and CBF of the segmented normal brain parenchyma with the absolute values in the literature. Using the scaling factors, the relative values were converted to the absolute CBV and CBF. Voxels with either CBV > 8 mL/100 g or CBF > 100 mL/100 g/min were characterized as vessel voxels and were excluded from the quantitative measurements. Results. The segmented brain parenchyma with normal perfusion was consistent with the angiographic findings for each patient. We confirmed the necessity of dual thresholds including CBF and CBV for proper removal of vessel voxels. The scaling factors were 0.208 ± 0.041 for CBV, and 0.168 ± 0.037, 0.172 ± 0.037 for CBF calculated using standard and circulant singular value decomposition techniques, respectively. Conclusion. The automatic scaling and vessel removal techniques provide an alternative method for obtaining improved quantitative assessment of CBV and CBF in patients with thromboembolic cerebral arterial disease.

  1. Quantitative agreement between [(15)O]H2O PET and model free QUASAR MRI-derived cerebral blood flow and arterial blood volume.

    Science.gov (United States)

    Heijtel, D F R; Petersen, E T; Mutsaerts, H J M M; Bakker, E; Schober, P; Stevens, M F; van Berckel, B N M; Majoie, C B L M; Booij, J; van Osch, M J P; van Bavel, E T; Boellaard, R; Lammertsma, A A; Nederveen, A J

    2016-04-01

    The purpose of this study was to assess whether there was an agreement between quantitative cerebral blood flow (CBF) and arterial cerebral blood volume (CBVA) measurements by [(15)O]H2O positron emission tomography (PET) and model-free QUASAR MRI. Twelve healthy subjects were scanned within a week in separate MRI and PET imaging sessions, after which quantitative and qualitative agreement between both modalities was assessed for gray matter, white matter and whole brain region of interests (ROI). The correlation between CBF measurements obtained with both modalities was moderate to high (r(2): 0.28-0.60, P QUASAR significantly underestimated CBF by 30% (P QUASAR yielding values that were only 27% of the [(15)O]H2O-derived values (P QUASAR MRI, indicating similar qualitative CBVA and CBF information by both modalities. In conclusion, the results of this study demonstrate that QUASAR MRI and [(15)O]H2O PET provide similar CBF and CBVA information, but with systematic quantitative discrepancies. Copyright © 2016 John Wiley & Sons, Ltd.

  2. Quantitative assessment of lung volumes using multi-detector row computed tomography (MDCT) in patients with chronic obstructive pulmonary disease (COPD)

    International Nuclear Information System (INIS)

    Lee, Sang Min; Hur, Jin; Kim, Tae Hoon; Kim, Sang Jin; Kim, Hyung Jung

    2008-01-01

    To evaluate the clinical value of the multi-detector row computed tomography (MDCT) in the quantitative assessment of lung volumes and to assess the relationship between the MDCT results and disease severity as determined by a pulmonary function test (PFT) in Chronic Obstructive Pulmonary Disease (COPD) patients. We performed a PFT and MDCT on 39 COPD patients. Using the GOLD classifications, we divided the patients into three groups according to disease severity; stage I (mild, n = 10), stage II (moderate, n = 15), and stage III (severe, n = 14). Using the pulmo-CT software program, we measured the proportion of lung volumes with attenuation values below -910 and -950 HU. The mean FEV1 (% of predicted) and FEV1/FVC was 82.2 ± 2% and 66.2 ± 3% in stage I, 53.5 ± 11% and 52 ± 6% in stage II, and 32.3 ± 7% and 44.2% ± 13% in stage III, respectively. Differences in lung volume percentage at each of the thresholds (-910 and -950 HU) among the 3 stages were statistically significant (ρ < 0.01, ρ < 0.01) and correlated well with the FEV1 and FEV1/FVC (r = -0.803, r -0.766, r = -0.817, and r = -0.795, respectively). The volumetric measurement obtained by MDCT provides an accurate means of quantifying pulmonary emphysema

  3. Comparison of quantitative estimation of intracerebral hemorrhage and infarct volumes after thromboembolism in an embolic stroke model

    DEFF Research Database (Denmark)

    Eriksen, Nina; Rasmussen, Rune Skovgaard; Overgaard, Karsten

    2014-01-01

    . Group 1 was treated with saline, and group 2 was treated with 20 mg/kg recombinant tissue plasminogen activator to promote intracerebral hemorrhages. Stereology, semiautomated computer estimation, and manual erythrocyte counting were used to test the precision and efficiency of determining the size...... measurements, the stereological method was the most efficient and advantageous. CONCLUSIONS: We found that stereology was the superior method for quantification of hemorrhagic volume, especially for rodent petechial bleeding, which is otherwise difficult to measure. Our results suggest the possibility...

  4. An improved method to quantitate mature plant microRNA in biological matrices using periodate treatment and internal control

    Science.gov (United States)

    MicroRNAs (miRNAs) ubiquitously exist in microorganisms, plants and animals, and appear to modulate a wide range of critical biological processes. However, no definitive conclusion has been reached regarding the uptake of exogenous dietary small RNAs into mammalian circulation and organs and cross-k...

  5. Quantitative autoradiography of radionuclides in biological tissues by high resolution nuclear analysis: application in radio-toxicology and dosimetry

    International Nuclear Information System (INIS)

    Aubineau Laniece, I.

    1997-01-01

    In the framework of radiation damage on cells in living organisms an auto-radiograph, based on the STIC method, has been developed for the particles detection. This apparatus associates a thin scintillator with a photosensitive detector (CCD). The design and the performance of this well adapted tool for low activity biological samples study, are described. (A.L.B.)

  6. Cellular Phone-Based Image Acquisition and Quantitative Ratiometric Method for Detecting Cocaine and Benzoylecgonine for Biological and Forensic Applications

    OpenAIRE

    Cadle, Brian A.; Rasmus, Kristin C.; Varela, Juan A.; Leverich, Leah S.; O’Neill, Casey E.; Bachtell, Ryan K.; Cooper, Donald C.

    2010-01-01

    Here we describe the first report of using low-cost cellular or web-based digital cameras to image and quantify standardized rapid immunoassay strips as a new point-of-care diagnostic and forensics tool with health applications. Quantitative ratiometric pixel density analysis (QRPDA) is an automated method requiring end-users to utilize inexpensive (~ $1 USD/each) immunotest strips, a commonly available web or mobile phone camera or scanner, and internet or cellular service. A model is descri...

  7. Quantitative assessment of inter-clinician variability of target volume delineation for medulloblastoma: quality assurance for the SIOP PNET 4 trial protocol

    International Nuclear Information System (INIS)

    Coles, Charlotte E.; Hoole, Andrew C.F.; Harden, Susan V; Burnet, Neil G.; Twyman, Nicola; Taylor, Roger E.; Kortmann, Rolf D.; Williams, Michael V.

    2003-01-01

    Background and purpose: To assess inter-clinician variability amongst specialist paediatric radiation oncologists in delineating clinical target volumes for treating medulloblastoma as a quality assurance exercise prior to the introduction of the SIOP PNET 4 trial protocol of conformal radiotherapy to the posterior fossa and tumour bed. Patients and methods: Participants from 17 UK centres attended an educational meeting and then completed a clinical planning exercise to outline: (1) the whole posterior fossa and (2) the tumour bed. Quantitative analysis of the volumes, lengths, spatial positioning and axial planes for each individual was carried out and variation between individuals analysed. Results: Outlining of the posterior fossa was reasonably consistent, although most variation was seen in defining the superior border of the tentorium. A major difference was the decision whether or not to include the post-surgical meningocoele in the clinical target volume (CTV). The CTV for the tumour bed was under treated by all participants due to lack of inclusion of pre-operative tumour extent. Conclusions: This exercise demonstrated several ambiguities in the draft protocol and highlighted particular areas of inter-clinician variation. Consequently the protocol was revised and improved to take account of these findings. We recommend that planning exercises, in conjunction with education and training, should be implemented before the start of any new radiotherapy trial. In the future, the use of image transfer will allow prospective peer review of target volumes before treatment commences. These measures are essential to ensure that alterations in clinical practice are achieved in a uniform way

  8. Hippocampal volume change measurement: quantitative assessment of the reproducibility of expert manual outlining and the automated methods FreeSurfer and FIRST.

    Science.gov (United States)

    Mulder, Emma R; de Jong, Remko A; Knol, Dirk L; van Schijndel, Ronald A; Cover, Keith S; Visser, Pieter J; Barkhof, Frederik; Vrenken, Hugo

    2014-05-15

    -year μL volume change, with LoA of ±218 μL for FreeSurfer, ±319 μL for expert manual delineation, and ±333 μL for FIRST. Approximate p-values indicated that reproducibility was better for FreeSurfer than for manual or FIRST, and that manual and FIRST did not differ. Inclusion of failed automated segmentations led to worsening of reproducibility of both automated methods for 1-year raw and percentage volume change. Quantitative reproducibility values of 1-year microliter and percentage hippocampal volume change were roughly similar between expert manual outlining, FIRST and FreeSurfer, but FreeSurfer reproducibility was statistically significantly superior to both manual outlining and FIRST after exclusion of failed segmentations. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Quantitative assessment of primary mitral regurgitation using left ventricular volumes obtained with new automated three-dimensional transthoracic echocardiographic software: A comparison with 3-Tesla cardiac magnetic resonance.

    Science.gov (United States)

    Levy, Franck; Marechaux, Sylvestre; Iacuzio, Laura; Schouver, Elie Dan; Castel, Anne Laure; Toledano, Manuel; Rusek, Stephane; Dor, Vincent; Tribouilloy, Christophe; Dreyfus, Gilles

    2018-03-30

    Quantitative assessment of primary mitral regurgitation (MR) using left ventricular (LV) volumes obtained with three-dimensional transthoracic echocardiography (3D TTE) recently showed encouraging results. Nevertheless, 3D TTE is not incorporated into everyday practice, as current LV chamber quantification software products are time consuming. To investigate the accuracy and reproducibility of new automated fast 3D TTE software (HeartModel A.I. ; Philips Healthcare, Andover, MA, USA) for the quantification of LV volumes and MR severity in patients with isolated degenerative primary MR; and to compare regurgitant volume (RV) obtained with 3D TTE with a cardiac magnetic resonance (CMR) reference. Fifty-three patients (37 men; mean age 64±12 years) with at least mild primary isolated MR, and having comprehensive 3D TTE and CMR studies within 24h, were eligible for inclusion. MR RV was calculated using the proximal isovelocity surface area (PISA) method and the volumetric method (total LV stroke volume minus aortic stroke volume) with either CMR or 3D TTE. Inter- and intraobserver reproducibility of 3D TTE was excellent (coefficient of variation≤10%) for LV volumes. MR RV was similar using CMR and 3D TTE (57±23mL vs 56±28mL; P=0.22), but was significantly higher using the PISA method (69±30mL; P<0.05 compared with CMR and 3D TTE). The PISA method consistently overestimated MR RV compared with CMR (bias 12±21mL), while no significant bias was found between 3D TTE and CMR (bias 2±14mL). Concordance between echocardiography and CMR was higher using 3D TTE MR grading (intraclass correlation coefficient [ICC]=0.89) than with PISA MR grading (ICC=0.78). Complete agreement with CMR grading was more frequent with 3D TTE than with the PISA method (76% vs 63%). 3D TTE RV assessment using the new generation of automated software correlates well with CMR in patients with isolated degenerative primary MR. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  10. Leptospira interrogans causes quantitative and morphological disturbances in adherens junctions and other biological groups of proteins in human endothelial cells.

    Science.gov (United States)

    Sato, Hiromi; Coburn, Jenifer

    2017-07-01

    Pathogenic Leptospira transmits from animals to humans, causing the zoonotic life-threatening infection called leptospirosis. This infection is reported worldwide with higher risk in tropical regions. Symptoms of leptospirosis range from mild illness to severe illness such as liver damage, kidney failure, respiratory distress, meningitis, and fatal hemorrhagic disease. Invasive species of Leptospira rapidly disseminate to multiple tissues where this bacterium damages host endothelial cells, increasing vascular permeability. Despite the burden in humans and animals, the pathogenic mechanisms of Leptospira infection remain to be elucidated. The pathogenic leptospires adhere to endothelial cells and permeabilize endothelial barriers in vivo and in vitro. In this study, human endothelial cells were infected with the pathogenic L. interrogans serovar Copenhageni or the saprophyte L. biflexa serovar Patoc to investigate morphological changes and other distinctive phenotypes of host cell proteins by fluorescence microscopy. Among those analyzed, 17 proteins from five biological classes demonstrated distinctive phenotypes in morphology and/or signal intensity upon infection with Leptospira. The affected biological groups include: 1) extracellular matrix, 2) intercellular adhesion molecules and cell surface receptors, 3) intracellular proteins, 4) cell-cell junction proteins, and 5) a cytoskeletal protein. Infection with the pathogenic strain most profoundly disturbed the biological structures of adherens junctions (VE-cadherin and catenins) and actin filaments. Our data illuminate morphological disruptions and reduced signals of cell-cell junction proteins and filamentous actin in L. interrogans-infected endothelial cells. In addition, Leptospira infection, regardless of pathogenic status, influenced other host proteins belonging to multiple biological classes. Our data suggest that this zoonotic agent may damage endothelial cells via multiple cascades or pathways

  11. Leptospira interrogans causes quantitative and morphological disturbances in adherens junctions and other biological groups of proteins in human endothelial cells.

    Directory of Open Access Journals (Sweden)

    Hiromi Sato

    2017-07-01

    Full Text Available Pathogenic Leptospira transmits from animals to humans, causing the zoonotic life-threatening infection called leptospirosis. This infection is reported worldwide with higher risk in tropical regions. Symptoms of leptospirosis range from mild illness to severe illness such as liver damage, kidney failure, respiratory distress, meningitis, and fatal hemorrhagic disease. Invasive species of Leptospira rapidly disseminate to multiple tissues where this bacterium damages host endothelial cells, increasing vascular permeability. Despite the burden in humans and animals, the pathogenic mechanisms of Leptospira infection remain to be elucidated. The pathogenic leptospires adhere to endothelial cells and permeabilize endothelial barriers in vivo and in vitro. In this study, human endothelial cells were infected with the pathogenic L. interrogans serovar Copenhageni or the saprophyte L. biflexa serovar Patoc to investigate morphological changes and other distinctive phenotypes of host cell proteins by fluorescence microscopy. Among those analyzed, 17 proteins from five biological classes demonstrated distinctive phenotypes in morphology and/or signal intensity upon infection with Leptospira. The affected biological groups include: 1 extracellular matrix, 2 intercellular adhesion molecules and cell surface receptors, 3 intracellular proteins, 4 cell-cell junction proteins, and 5 a cytoskeletal protein. Infection with the pathogenic strain most profoundly disturbed the biological structures of adherens junctions (VE-cadherin and catenins and actin filaments. Our data illuminate morphological disruptions and reduced signals of cell-cell junction proteins and filamentous actin in L. interrogans-infected endothelial cells. In addition, Leptospira infection, regardless of pathogenic status, influenced other host proteins belonging to multiple biological classes. Our data suggest that this zoonotic agent may damage endothelial cells via multiple cascades or

  12. Leptospira interrogans causes quantitative and morphological disturbances in adherens junctions and other biological groups of proteins in human endothelial cells

    Science.gov (United States)

    Sato, Hiromi

    2017-01-01

    Pathogenic Leptospira transmits from animals to humans, causing the zoonotic life-threatening infection called leptospirosis. This infection is reported worldwide with higher risk in tropical regions. Symptoms of leptospirosis range from mild illness to severe illness such as liver damage, kidney failure, respiratory distress, meningitis, and fatal hemorrhagic disease. Invasive species of Leptospira rapidly disseminate to multiple tissues where this bacterium damages host endothelial cells, increasing vascular permeability. Despite the burden in humans and animals, the pathogenic mechanisms of Leptospira infection remain to be elucidated. The pathogenic leptospires adhere to endothelial cells and permeabilize endothelial barriers in vivo and in vitro. In this study, human endothelial cells were infected with the pathogenic L. interrogans serovar Copenhageni or the saprophyte L. biflexa serovar Patoc to investigate morphological changes and other distinctive phenotypes of host cell proteins by fluorescence microscopy. Among those analyzed, 17 proteins from five biological classes demonstrated distinctive phenotypes in morphology and/or signal intensity upon infection with Leptospira. The affected biological groups include: 1) extracellular matrix, 2) intercellular adhesion molecules and cell surface receptors, 3) intracellular proteins, 4) cell-cell junction proteins, and 5) a cytoskeletal protein. Infection with the pathogenic strain most profoundly disturbed the biological structures of adherens junctions (VE-cadherin and catenins) and actin filaments. Our data illuminate morphological disruptions and reduced signals of cell-cell junction proteins and filamentous actin in L. interrogans-infected endothelial cells. In addition, Leptospira infection, regardless of pathogenic status, influenced other host proteins belonging to multiple biological classes. Our data suggest that this zoonotic agent may damage endothelial cells via multiple cascades or pathways

  13. Human exposure to radiation following the release of radioactivity from a reactor accident: a quantitative assessment of the biological consequences

    International Nuclear Information System (INIS)

    Smith, H.; Stather, J.W.

    1976-11-01

    The objective of this review is to provide a biological basis upon which to assess the consequences of the exposure of a population to radioactivity released after a reactor accident. Depending upon the radiation dose, both early and late somatic damage could occur in the exposed population and hereditary effects may occur in their descendants. The development of dose-effect relationships has been based upon the limited amount of information available on humans, supplemented by data obtained from experiments on animals. (author)

  14. The Effects of Simultaneous Application of Different Organic and Biological Fertilizers on Quantitative and Qualitative Characteristics of Cucurbita pepo L.

    Directory of Open Access Journals (Sweden)

    M Jahan

    2013-08-01

    Full Text Available Understanding of relations and interactions between ecosystem’s components and plants is one of the main conditions for sustainable production of medicinal plants. To study the effect of simultaneous application of organic and biological fertilizers on yield and yield components of zucchini squash, a split plot arrangement of factors based on randomized complete block design with tree replications was used during 2009-10 growing season. The mainplot factor was the type of organic fertilizers, including 1-cow manure, 2-sheep manure, 3-chicken manure, 4-vermicompost and 5-control. The subplot factor was the biofertilizer (namely Nitragin, containing Azotobacter sp. , Azospirillum sp. and Pseudomonas sp., utilization. The results showed the positive but non significant effect of organic and biological fertilizers on yield and yield components of zucchini squash. Amongst the organic fertilizers, cow and chicken manure, have superiority compared the others. The highest seed oil and protein percent resulted in chicken manure, although there was not significant different between treatments due to seed oil percent. The positive effect of organic and biological fertilizers on seed yield was higher than fruit yield. Positive correlations found between fruit and seed yield, and between one fruit weight and one fruit seed weight (R2=0.72** and 0.56**, respectively. At a glance, cow manure solely application was better than its application with nitragin. Nitragin application has no significant effect on some traits, when utilized with sheep manure and vermicompost. The possibilities of antagonistic effect among organic and biological fertilizers needs to be more studied.

  15. The detection and quantitative analysis of the psychoactive component of Salvia divinorum, salvinorin A, in human biological fluids using liquid chromatography-mass spectrometry.

    Science.gov (United States)

    McDonough, Pamela C; Holler, Justin M; Vorce, Shawn P; Bosy, Thomas Z; Magluilo, Joseph; Past, Marilyn R

    2008-01-01

    Salvia divinorum, a member of the mint plant family, has hallucinogenic properties that have become increasingly sought after by recreational drug users. The main psychoactive component, salvinorin A, has potency comparable to lysergic acid diethylamide. Though still legal to possess in most of the United States and much of Europe, little is known regarding the compound's long-term health effects, addiction liability, and pharmacokinetics. Limited data are available in the scientific literature, and few analytical methods are published for the detection in human biological fluids. These factors contribute to the unfamiliarity of the compound and complicate the method development process necessary to accommodate special requested testing for salvinorin A. A sensitive analytical method for the detection and quantitation of salvinorin A in human biological fluids was developed and validated to resolve analytical shortcomings. The method utilizes a solid-phase extraction technique coupled with liquid chromatography-electrospray ionization mass spectrometry operated in selected ion monitoring mode. The assay has a linear range of 5.0-100 ng/mL with a correlation coefficient of 0.997. The limit of detection and limit of quantitation were experimentally determined as 2.5 and 5.0 ng/mL, respectively. The method has been applied to blood and urine samples successfully and can be used to detect the presence of salvinorin A in forensic testing.

  16. Effectiveness of quantitative MAA SPECT/CT for the definition of vascularized hepatic volume and dosimetric approach: phantom validation and clinical preliminary results in patients with complex hepatic vascularization treated with yttrium-90-labeled microspheres.

    Science.gov (United States)

    Garin, Etienne; Lenoir, Laurence; Rolland, Yan; Laffont, Sophie; Pracht, Marc; Mesbah, Habiba; Porée, Philippe; Ardisson, Valérie; Bourguet, Patrick; Clement, Bruno; Boucher, Eveline

    2011-12-01

    The goal of this study was to assess the use of quantitative single-photon emission computed tomography/computed tomography (SPECT/CT) analysis for vascularized volume measurements in the use of the yttrium-90-radiolabeled microspheres (TheraSphere). A phantom study was conducted for the validation of SPECT/CT volume measurement. SPECT/CT quantitative analysis was used for the measurement of the volume of distribution of the albumin macroaggregates (MAA; i.e., the vascularized volume) in the liver and the tumor, and the total activity contained in the liver and the tumor in four consecutive patients presenting with a complex liver vascularization referred for a treatment with TheraSphere. SPECT/CT volume measurement proved to be accurate (mean error <7%) and reproducible (interobserver concordance 0.99). For eight treatments, in cases of complex hepatic vascularization, the hepatic volumes based on angiography and CT led to a relative overestimation or underestimation of the vascularized hepatic volume by 43.2 ± 32.7% (5-87%) compared with SPECT/CT analyses. The vascularized liver volume taken into account calculated from SPECT/CT data, instead of angiography and CT data, results in modifying the activity injected for three treatments of eight. Moreover, quantitative analysis of SPECT/CT allows us to calculate the absorbed dose in the tumor and in the healthy liver, leading to doubling of the injected activity for one treatment of eight. MAA SPECT/CT is accurate for volume measurements. It provides a valuable contribution to the therapeutic planning of patients presenting with complex hepatic vascularization, in particular for calculating the vascularized liver volume, the activity to be injected and the absorbed doses. Studies should be conducted to assess the role of quantitative MAA/SPECT CT in therapeutic planning.

  17. TU-F-CAMPUS-T-05: Dose Escalation to Biological Tumor Volumes of Prostate Cancer Patients Using Gold Nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Jermoumi, M; Ngwa, W [Department of Physics and Applied Physics, Medical Physics Program, University of Massachusetts Lowell (United States); Department of Radiation Oncology, Dana Farber Cancer Insitute, Brigham and Women’s Hospital, Harvard Medical, Boston, MA (United States); Sajo, E [Department of Physics and Applied Physics, Medical Physics Program, University of Massachusetts Lowell (United States); Houari, K [Department of Radiation Oncology, Dana Farber Cancer Insitute, Brigham and Women’s Hospital, Harvard Medical, Boston, MA (United States)

    2015-06-15

    Purpose: Studies have shown that radiation boosting could help reduce prostate cancer (PCa) recurrence. Biological tumor volumes (BTV) are a high priority for such radiation boosting. The purpose of this study is to investigate the potential of radiation boosting of real patient BTVs using gold nanoparticles (GNP) released from gold-loaded brachytherapy spacers (GBS) during brachytherapy. Methods: The BTVs of 12 patients having prostate adenocarcinoma identified with positron emission tomography (PET) and CT scanner using C-11 labeled tracer [11C]acetate were investigated. The initial GNP concentration and time to achieve a dose enhancement effect (DEF) of 2 was simulated using the freely downloadable software RAID APP. The investigations were carried out for low dose rate (LDR) brachytherapy sources (BTS) described in AAPM Task Group report 43: Cs-131, I-125, and Pd-103. In first case, we used 7 mg/g and 18 mg/g of GNP initial concentrations to estimate the time needed for released GNP to achieve a DEF of 2 for the different BTS, and compare with clinically relevant treatment times. In second case, we calculated the initial concentration of GNPs needed to achieve a DEF of 2 during the time the BTS would typically deliver 50%, 70% and 90% of the total dose. Results: For an initial concentration of 18 mg/g, when using Cs-131, and Pd-103, a DEF of 2 could only be achieved for BTV of 3.3 cm3 and 1 cm3 respectively. Meanwhile a DEF of 2 could be achieved for all 12 BTVs when using I-125. To achieve a DEF of 2 for all patients using Cs-131 and Pd-103, much higher initial concentrations would have to be used than have been typically employed in pre-clinical studies. Conclusion: The I-125 is the most viable BTS that can be employed with GBS to guide dose painting treatment planning for localized PCa.

  18. Quantitation of regional cerebral blood flow corrected for partial volume effect using O-15 water and PET: I. Theory, error analysis, and stereologic comparison

    DEFF Research Database (Denmark)

    Lida, H; Law, I; Pakkenberg, B

    2000-01-01

    Limited spatial resolution of positron emission tomography (PET) can cause significant underestimation in the observed regional radioactivity concentration (so-called partial volume effect or PVE) resulting in systematic errors in estimating quantitative physiologic parameters. The authors have...... formulated four mathematical models that describe the dynamic behavior of a freely diffusible tracer (H215O) in a region of interest (ROI) incorporating estimates of regional tissue flow that are independent of PVE. The current study was intended to evaluate the feasibility of these models and to establish...... a methodology to accurately quantify regional cerebral blood flow (CBF) corrected for PVE in cortical gray matter regions. Five monkeys were studied with PET after IV H2(15)O two times (n = 3) or three times (n = 2) in a row. Two ROIs were drawn on structural magnetic resonance imaging (MRI) scans and projected...

  19. Scanning transmission ion microscopy mass measurements for quantitative trace element analysis within biological samples and validation using atomic force microscopy thickness measurements

    Energy Technology Data Exchange (ETDEWEB)

    Deves, Guillaume [Laboratoire de chimie nucleaire analytique et bioenvironnementale, UMR 5084, CNRS-Universite de Bordeaux 1, BP 120 Chemin du solarium, F33175 Gradignan cedex (France)]. E-mail: deves@cenbg.in2p3.fr; Cohen-Bouhacina, Touria [Centre de Physique Moleculaire Optique et Hertzienne, Universite de Bordeaux 1, 351, cours de la Liberation, F33405 Talence cedex (France); Ortega, Richard [Laboratoire de chimie nucleaire analytique et bioenvironnementale, UMR 5084, CNRS-Universite de Bordeaux 1, BP 120 Chemin du solarium, F33175 Gradignan cedex (France)

    2004-10-08

    We used the nuclear microprobe techniques, micro-PIXE (particle-induced X-ray emission), micro-RBS (Rutherford backscattering spectrometry) and scanning transmission ion microscopy (STIM) in order to perform the characterization of trace element content and spatial distribution within biological samples (dehydrated cultured cells, tissues). The normalization of PIXE results was usually expressed in terms of sample dry mass as determined by micro-RBS recorded simultaneously to micro-PIXE. However, the main limit of RBS mass measurement is the sample mass loss occurring during irradiation and which could be up to 30% of the initial sample mass. We present here a new methodology for PIXE normalization and quantitative analysis of trace element within biological samples based on dry mass measurement performed by mean of STIM. The validation of STIM cell mass measurements was obtained in comparison with AFM sample thickness measurements. Results indicated the reliability of STIM mass measurement performed on biological samples and suggested that STIM should be performed for PIXE normalization. Further information deriving from direct confrontation of AFM and STIM analysis could as well be obtained, like in situ measurements of cell specific gravity within cells compartment (nucleolus and cytoplasm)

  20. Quantitative assessment of inter-observer variability in target volume delineation on stereotactic radiotherapy treatment for pituitary adenoma and meningioma near optic tract

    International Nuclear Information System (INIS)

    Yamazaki, Hideya; Ogita, Mikio; Yamashita, Koichi; Kotsuma, Tadayuki; Shiomi, Hiroya; Tsubokura, Takuji; Kodani, Naohiro; Nishimura, Takuya; Aibe, Norihiro; Udono, Hiroki; Nishikata, Manabu; Baba, Yoshimi

    2011-01-01

    To assess inter-observer variability in delineating target volume and organs at risk in benign tumor adjacent to optic tract as a quality assurance exercise. We quantitatively analyzed 21 plans made by 11 clinicians in seven CyberKnife centers. The clinicians were provided with a raw data set (pituitary adenoma and meningioma) including clinical information, and were asked to delineate the lesions and create a treatment plan. Their contouring and plans (10 adenoma and 11 meningioma plans), were then compared. In addition, we estimated the influence of differences in contouring by superimposing the respective contours onto a default plan. The median planning target volume (PTV) and the ratio of the largest to the smallest contoured volume were 9.22 cm 3 (range, 7.17 - 14.3 cm 3 ) and 1.99 for pituitary adenoma, and 6.86 cm 3 (range 6.05 - 14.6 cm 3 ) and 2.41 for meningioma. PTV volume was 10.1 ± 1.74 cm 3 for group 1 with a margin of 1 -2 mm around the CTV (n = 3) and 9.28 ± 1.8 cm 3 (p = 0.51) for group 2 with no margin (n = 7) in pituitary adenoma. In meningioma, group 1 showed larger PTV volume (10.1 ± 3.26 cm 3 ) than group 2 (6.91 ± 0.7 cm 3 , p = 0.03). All submitted plan keep the irradiated dose to optic tract within the range of 50 Gy (equivalent total doses in 2 Gy fractionation). However, contours superimposed onto the dose distribution of the default plan indicated that an excessive dose 23.64 Gy (up to 268% of the default plan) in pituitary adenoma and 24.84 Gy (131% of the default plan) in meningioma to the optic nerve in the contours from different contouring. Quality assurance revealed inter-observer variability in contour delineation and their influences on planning for pituitary adenoma and meningioma near optic tract

  1. Quantitative determination of polysulfide in albumins, plasma proteins and biological fluid samples using a novel combined assays approach.

    Science.gov (United States)

    Ikeda, Mayumi; Ishima, Yu; Shibata, Akitomo; Chuang, Victor T G; Sawa, Tomohiro; Ihara, Hideshi; Watanabe, Hiroshi; Xian, Ming; Ouchi, Yuya; Shimizu, Taro; Ando, Hidenori; Ukawa, Masami; Ishida, Tatsuhiro; Akaike, Takaaki; Otagiri, Masaki; Maruyama, Toru

    2017-05-29

    Hydrogen sulfide (H 2 S) signaling involves polysulfide (RSS n SR') formation on various proteins. However, the current lack of sensitive polysulfide detection assays poses methodological challenges for understanding sulfane sulfur homeostasis and signaling. We developed a novel combined assay by modifying Sulfide Antioxidant Buffer (SAOB) to produce an "Elimination Method of Sulfide from Polysulfide" (EMSP) treatment solution that liberates sulfide, followed with methylene blue (MB) sulfide detection assay. The combined EMSP-MB sulfide detection assay performed on low molecular weight sulfur species showed that sulfide was produced from trisulfide compounds such as glutathione trisulfide and diallyl trisulfide, but not from the thiol compounds such as cysteine, cystine and glutathione. In the case of plasma proteins, this novel combined detection assay revealed that approximately 14.7, 1.7, 3.9, 3.7 sulfide mol/mol released from human serum albumin, α 1 -anti-trypsin, α 1 -acid glycoprotein and ovalbumin, respectively, suggesting that serum albumin is a major pool of polysulfide in human blood circulation. Taken together with the results of albumins of different species, the liberated sulfide has a good correlation with cysteine instead of methionine, indicating the site of incorporation of polysulfide is cysteine. With this novel sulfide detention assay, approximately 8,000, 120 and 1100 μM of polysulfide concentrations was quantitated in human healthy plasma, saliva and tear, respectively. Our promising polysulfide specific detection assay can be a very important tool because quantitative determination of polysulfide sheds light on the functional consequence of protein-bound cysteine polysulfide and expands the research area of reactive oxygen to reactive polysulfide species. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Impact of image denoising on image quality, quantitative parameters and sensitivity of ultra-low-dose volume perfusion CT imaging

    International Nuclear Information System (INIS)

    Othman, Ahmed E.; Brockmann, Carolin; Afat, Saif; Pjontek, Rastislav; Nikoubashman, Omid; Brockmann, Marc A.; Wiesmann, Martin; Yang, Zepa; Kim, Changwon; Nikolaou, Konstantin; Kim, Jong Hyo

    2016-01-01

    To examine the impact of denoising on ultra-low-dose volume perfusion CT (ULD-VPCT) imaging in acute stroke. Simulated ULD-VPCT data sets at 20 % dose rate were generated from perfusion data sets of 20 patients with suspected ischemic stroke acquired at 80 kVp/180 mAs. Four data sets were generated from each ULD-VPCT data set: not-denoised (ND); denoised using spatiotemporal filter (D1); denoised using quanta-stream diffusion technique (D2); combination of both methods (D1 + D2). Signal-to-noise ratio (SNR) was measured in the resulting 100 data sets. Image quality, presence/absence of ischemic lesions, CBV and CBF scores according to a modified ASPECTS score were assessed by two blinded readers. SNR and qualitative scores were highest for D1 + D2 and lowest for ND (all p ≤ 0.001). In 25 % of the patients, ND maps were not assessable and therefore excluded from further analyses. Compared to original data sets, in D2 and D1 + D2, readers correctly identified all patients with ischemic lesions (sensitivity 1.0, kappa 1.0). Lesion size was most accurately estimated for D1 + D2 with a sensitivity of 1.0 (CBV) and 0.94 (CBF) and an inter-rater agreement of 1.0 and 0.92, respectively. An appropriate combination of denoising techniques applied in ULD-VPCT produces diagnostically sufficient perfusion maps at substantially reduced dose rates as low as 20 % of the normal scan. (orig.)

  3. The influence of quantitative tumor volume measurements on local control in advanced head and neck cancer using concomitant boost accelerated superfractionated irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Christopher R; Khandelwal, Shiv R; Schmidt-Ullrich, Rupert K; Ravalese, Joseph; Wazer, David E

    1995-06-15

    Purpose: Current methods to clinically define head and neck tumor bulk are qualitative and imprecise. Although the American Joint Committee on Cancer (AJCC) staging system is important for this purpose, limitations exist. This study will investigate the prognostic value of computed tomography (CT) derived tumor volume measurements in comparison to AJCC stage and other significant variables. Materials and Methods: Seventy-six patients with advanced head and neck squamous cell carcinoma were treated with concomitant boost accelerated superfractionated irradiation. Doses ranged from 68.4-73.8 Gy (median 70.2 Gy). Good quality pretherapy CT scans were available in 51 patients. Total tumor volume (TTV) estimates were derived from these scans using digital integration of primary tumor and metastatic lymphadenopathy. Actuarial and multivariate statistical techniques were applied to analyze local control. Results: Thirty-six-month local control was 63%. TTV ranged from 5-196 cm{sup 3} (median 35 cm{sup 3}) for all cases, 5-142 cm{sup 3} (median 17 cm{sup 3}) for those controlled, and 16-196 cm{sup 3} (median 47 cm{sup 3}) for local failures. There was a significant increase in failures above 35 cm{sup 3}. Univariate analysis found that TTV, T-stage, N-stage, and primary site were each significant prognostic variables. Local control for TTV {<=}35 cm{sup 3} was 92% at 36 months vs. 34% for TTV >35 cm{sup 3} (p = 0.0001). Multivariate analysis, however, found that TTV, primary site, and sex were important as independent variables; T and N stage were not independently significant unless TTV was removed from the model. Conclusions: This study demonstrates the prognostic significance of TTV in advanced carcinoma of the head and neck. This variable appears to be a more predictive than AJCC clinical stage. Quantitative tumor volume measurements may prove to be a useful parameter in future analyses of head and neck cancer.

  4. SU-C-210-06: Quantitative Evaluation of Dosimetric Effects Resulting From Positional Variations of Pancreatic Tumor Volumes

    Energy Technology Data Exchange (ETDEWEB)

    Yu, S; Sehgal, V; Wei, R; Lawrenson, L; Kuo, J; Hanna, N; Ramsinghani, N; Daroui, P; Al-Ghazi, M [University of California, Orange, CA (United States)

    2015-06-15

    Purpose: The aim of this study is to quantify dosimetric effects resulting from variation in pancreatic tumor position assessed by bony anatomy and implanted fiducial markers Methods: Twelve pancreatic cancer patients were retrospectively analyzed for this study. All patients received modulated arc therapy (VMAT) treatment using fiducial-based Image Guided Radiation Therapy (IGRT) to the intact pancreas. Using daily orthogonal kV and/or Cone beam CT images, the shift needed to co-register the daily pre-treatment images to reference CT from fiducial to bone (Fid-Bone) were recorded as Left-Right (LR), Anterior-Posterior (AP) and Superior-Inferior (SI). The original VMAT plan iso-center was shifted based on KV bone matching positions at 5 evenly spaced fractions. Dose coverage of the planning target volumes (PTVs) (V100%), mean dose to liver, kidney and stomach/duodenum were assessed in the modified plans. Results: A total of 306 fractions were analyzed. The absolute fiducial-bone positional shifts were greatest in the SI direction, (AP = 2.7 ± 3.0, LR = 2.8 ± 2.8, and SI 6.3 ± 7.9 mm, mean ± SD). The V100% was significantly reduced by 13.5%, (Fid-Bone = 95.3 ± 2.0 vs. 82.3 ± 11.8%, p=0.02). This varied widely among patients (Fid-Bone V100% Range = 2–60%), where 33% of patients had a reduction in V100% of more than 10%. The impact on OARs was greatest to the liver (Fid-Bone= 14.6 vs. 16.1 Gy, 10%), and stomach, (Fid-Bone = 23.9 vx. 25.5 Gy, 7%), however was not statistically significant (p=0.10 both). Conclusion: Compared to matching by fiducial markers, matching by bony anatomy would have substantially reduced the PTV coverage by 13.5%. This reinforces the importance of online position verification based on fiducial markers. Hence, implantation of fiducial markers is strongly recommended for pancreatic cancer patients undergoing intensity modulated radiation therapy treatments.

  5. Alpha-particle autoradiography in CR-39: a technique for quantitative assessment of alpha-emitters in biological tissue

    International Nuclear Information System (INIS)

    Fews, A.P.; Henshaw, D.L.

    1983-01-01

    The techniques for α-particle autoradiography based on the plastic nuclear track detector CR-39, previously reported, have been developed considerably. The techniques are applied to α-autoradiography of human lung tissue in particular but are applicable to any biological tissue. The most important developments are: (i) Improvements in the manufacture and pre-etching of the plastic. (ii) High resolution α-particle spectroscopy in CR-39 plastic based on the analysis of the structure of the etched track. (iii) Calculation of the effective thickness of tissue sampled by the plastic. (iv) A deconvolution analysis which takes the distributions of track length and dip angle in the plastic and determines the α-particle range spectrum and distribution of tissue activity with height above the plastic surface. (v) The analysis of radon diffusion in tissue to determine the mean radon diffusion distance in tissue and plastic. (author)

  6. Estimation of tumor volume and its prognostic significance to study the biological behavior of carcinoma of cervix

    Directory of Open Access Journals (Sweden)

    Leelavathi Dawson

    2016-01-01

    Results: The median age of the patients in this group was 47.5 years, with a range of 30–80 years. The major histological type of carcinoma among 40 cases is squamous cell carcinoma (SCC (in 90% of cases, and 10% had adenocarcinoma. Pathological staging of the carcinoma cervix showed stage Ib, IIa, IIb, and IVa (35%, 20%, 40%, and 5%. Tumor volume estimated on pathological specimens of 40 cases ranged from 230 cumm to 49,760 cumm with a mean of 14,844 cumm. 12 (30% cases had tumor volume more than 15,000 cumm, 12 (30% cases had tumor volume <5000 cumm and 16 (40% cases had tumor volume between 5000 and 15,000 cumm. 17% of the tumors with tumor volume <5000 cumm showed lymph node metastases, whereas 67% (out of 12cases of cases with tumor volume more than 15,000 cumm showed lymph node metastases. 67% of the tumors with tumor volume <5000 cumm showed 0/4 organs involvement, whereas all cases with tumor volume more than 15,000 cumm showed more than one organ involvement among vagina, uterus, parametrium or bladder/rectum. Fibronectin positivity was seen in 22 out of 44 cases (55%. Macrophages were seen surrounding the group of tumor cells by LN5 immunostaining. Conclusion: Tumor volume can be considered as an independent prognostic factor to assess the spread of the tumor. Cases with tumor volume <5000 cumm show low risk in terms of parametrial involvement and lymph node metastasis and those with tumor volume more than 15,000 cumm showed more organ spread. Fibronectin positivity carries some importance in low-risk cases. For macrophages, further detailed study needs to be carried out.

  7. Evaluation of ultrasound-assisted extraction as sample pre-treatment for quantitative determination of rare earth elements in marine biological tissues by inductively coupled plasma-mass spectrometry

    International Nuclear Information System (INIS)

    Costas, M.; Lavilla, I.; Gil, S.; Pena, F.; Calle, I.; Cabaleiro, N. de la; Bendicho, C.

    2010-01-01

    In this work, the determination of rare earth elements (REEs), i.e. Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu in marine biological tissues by inductively coupled-mass spectrometry (ICP-MS) after a sample preparation method based on ultrasound-assisted extraction (UAE) is described. The suitability of the extracts for ICP-MS measurements was evaluated. For that, studies were focused on the following issues: (i) use of clean up of extracts with a C18 cartridge for non-polar solid phase extraction; (ii) use of different internal standards; (iii) signal drift caused by changes in the nebulization efficiency and salt deposition on the cones during the analysis. The signal drift produced by direct introduction of biological extracts in the instrument was evaluated using a calibration verification standard for bracketing (standard-sample bracketing, SSB) and cumulative sum (CUSUM) control charts. Parameters influencing extraction such as extractant composition, mass-to-volume ratio, particle size, sonication time and sonication amplitude were optimized. Diluted single acids (HNO 3 and HCl) and mixtures (HNO 3 + HCl) were evaluated for improving the extraction efficiency. Quantitative recoveries for REEs were achieved using 5 mL of 3% (v/v) HNO 3 + 2% (v/v) HCl, particle size <200 μm, 3 min of sonication time and 50% of sonication amplitude. Precision, expressed as relative standard deviation from three independent extractions, ranged from 0.1 to 8%. In general, LODs were improved by a factor of 5 in comparison with those obtained after microwave-assisted digestion (MAD). The accuracy of the method was evaluated using the CRM BCR-668 (mussel tissue). Different seafood samples of common consumption were analyzed by ICP-MS after UAE and MAD.

  8. A propidium monoazide–quantitative PCR method for the detection and quantification of viable Enterococcus faecalis in large-volume samples of marine waters

    KAUST Repository

    Salam, Khaled W.; El-Fadel, Mutasem E.; Barbour, Elie K.; Saikaly, Pascal

    2014-01-01

    The development of rapid detection assays of cell viability is essential for monitoring the microbiological quality of water systems. Coupling propidium monoazide with quantitative PCR (PMA-qPCR) has been successfully applied in different studies for the detection and quantification of viable cells in small-volume samples (0.25-1.00 mL), but it has not been evaluated sufficiently in marine environments or in large-volume samples. In this study, we successfully integrated blue light-emitting diodes for photoactivating PMA and membrane filtration into the PMA-qPCR assay for the rapid detection and quantification of viable Enterococcus faecalis cells in 10-mL samples of marine waters. The assay was optimized in phosphate-buffered saline and seawater, reducing the qPCR signal of heat-killed E. faecalis cells by 4 log10 and 3 log10 units, respectively. Results suggest that high total dissolved solid concentration (32 g/L) in seawater can reduce PMA activity. Optimal PMA-qPCR standard curves with a 6-log dynamic range and detection limit of 102 cells/mL were generated for quantifying viable E. faecalis cells in marine waters. The developed assay was compared with the standard membrane filter (MF) method by quantifying viable E. faecalis cells in seawater samples exposed to solar radiation. The results of the developed PMA-qPCR assay did not match that of the standard MF method. This difference in the results reflects the different physiological states of E. faecalis cells in seawater. In conclusion, the developed assay is a rapid (∼5 h) method for the quantification of viable E. faecalis cells in marine recreational waters, which should be further improved and tested in different seawater settings. © 2014 Springer-Verlag Berlin Heidelberg.

  9. A propidium monoazide–quantitative PCR method for the detection and quantification of viable Enterococcus faecalis in large-volume samples of marine waters

    KAUST Repository

    Salam, Khaled W.

    2014-08-23

    The development of rapid detection assays of cell viability is essential for monitoring the microbiological quality of water systems. Coupling propidium monoazide with quantitative PCR (PMA-qPCR) has been successfully applied in different studies for the detection and quantification of viable cells in small-volume samples (0.25-1.00 mL), but it has not been evaluated sufficiently in marine environments or in large-volume samples. In this study, we successfully integrated blue light-emitting diodes for photoactivating PMA and membrane filtration into the PMA-qPCR assay for the rapid detection and quantification of viable Enterococcus faecalis cells in 10-mL samples of marine waters. The assay was optimized in phosphate-buffered saline and seawater, reducing the qPCR signal of heat-killed E. faecalis cells by 4 log10 and 3 log10 units, respectively. Results suggest that high total dissolved solid concentration (32 g/L) in seawater can reduce PMA activity. Optimal PMA-qPCR standard curves with a 6-log dynamic range and detection limit of 102 cells/mL were generated for quantifying viable E. faecalis cells in marine waters. The developed assay was compared with the standard membrane filter (MF) method by quantifying viable E. faecalis cells in seawater samples exposed to solar radiation. The results of the developed PMA-qPCR assay did not match that of the standard MF method. This difference in the results reflects the different physiological states of E. faecalis cells in seawater. In conclusion, the developed assay is a rapid (∼5 h) method for the quantification of viable E. faecalis cells in marine recreational waters, which should be further improved and tested in different seawater settings. © 2014 Springer-Verlag Berlin Heidelberg.

  10. Volume perfusion CT (VPCT) for the differential diagnosis of patients with suspected cerebral vasospasm: Qualitative and quantitative analysis of 3D parameter maps

    International Nuclear Information System (INIS)

    Dolatowski, K.; Malinova, V.; Frölich, A.M.J.; Schramm, R.; Haberland, U.; Klotz, E.; Mielke, D.; Knauth, M.; Schramm, P.

    2014-01-01

    Object: Cerebral vasospasm (CV) following subarachnoid hemorrhage (SAH) implies high risk for secondary ischemia. It requires early diagnosis to start treatment on time. We aimed to assess the utility of “whole brain” VPCT for detecting localization and characteristics of arterial vasospasm. Methods: 23 patients received a non-enhanced CT, VPCT and CTA of the brain. The distribution of ischemic lesions was analyzed on 3D-perfusion-parameter-maps of CBF, CBV, MTT, TTS, TTP, and TTD. CT-angiographic axial and coronal maximum-intensity-projections were reconstructed to determine arterial vasospasm. CT-data was compared to DSA, if performed additionally. Volume-of-interest placement was used to obtain quantitative mean VPCT values. Results: 82% patients (n = 19) had focal cerebral hypoperfusion. 100% sensitivity and 100% specificity was found for TTS (median 1.9 s), MTT (median 5.9 s) and TTD (median 7.6 s). CBV showed no significant differences. In 78% (n = 18) focal vessel aberrations could be detected either on CTA or DSA or on both. Conclusion: VPCT is a non-invasive method with the ability to detect focal perfusion deficits almost in the whole brain. While DSA remains to be the gold standard for detection of CV, VPCT has the potential to improve noninvasive diagnosis and treatment decisions

  11. Evaluation of the AGCU Expressmarker 16 and 22 PCR Amplification Kits Using Biological Samples Applied to FTA Micro Cards in Reduced Volume Direct PCR Amplification Reactions

    Directory of Open Access Journals (Sweden)

    Samantha J Ogden

    2015-01-01

    Full Text Available This study evaluated the performance of the  Wuxi AGCU ScienTech Incorporation (HuiShan, Wuxi, China AGCU Expressmarker 16 (EX 16 and 22 (EX22 short tandem repeat (STR amplification kits in reduced reaction volumes using direct polymerase chain reaction (PCR amplification workflows. The commercially available PowerPlex® 21 (PP21 System (Promega, Wisconsin, USA, which follows similar direct workflows, was used as a reference. Anticoagulate blood applied to chemically impregnated  FTA TM Micro Cards (GE Healthcare UK Limited, Amersham Place, Little Chalfont, Buckinghamshire, HP7 9NA, UK was used to represent a complex biological sample. Allelic concordance, first-pass success rate, average peak heights, heterozygous peak height ratios (HPHRs, and intracolor and intercolor peak height balance were determined. In reduced volume PCR reactions, the performances of both the EX16 and EX22 STR amplification kits were comparable to that of the PP21 System. The level of performance was maintained at PCR reaction volumes, which are 40% of that recommended. The EX22 and PP21 System kits possess comparable overlapping genome coverage. This study evaluated the performance of the AGCU EX16 and EX22 STR amplification kits in reduced PCR reaction volumes using direct workflows in combination with whole blood applied to FTA TM Micro Cards. Allelic concordance, first-pass success rate, average peak heights, HPHRs, and intracolor and intercolor peak height balance were determined. A concordance analysis was completed that compared the performance of the EX16 and EX22 kits using human blood applied to FTA Micro Cards in combination with full, half, and reduced PCR reaction volumes. The PP21 System (Promega was used as a reference kit. Where appropriate, the distributions of data were assessed using the Shapiro-Wilk test. For normally-distributed data, statistics were calculated using analysis of variance (ANOVA and for nonparametric data the Wilcoxon

  12. Quantitative analysis of biological responses to low dose-rate γ-radiation, including dose, irradiation time, and dose-rate

    International Nuclear Information System (INIS)

    Magae, J.; Furukawa, C.; Kawakami, Y.; Hoshi, Y.; Ogata, H.

    2003-01-01

    Full text: Because biological responses to radiation are complex processes dependent on irradiation time as well as total dose, it is necessary to include dose, dose-rate and irradiation time simultaneously to predict the risk of low dose-rate irradiation. In this study, we analyzed quantitative relationship among dose, irradiation time and dose-rate, using chromosomal breakage and proliferation inhibition of human cells. For evaluation of chromosome breakage we assessed micronuclei induced by radiation. U2OS cells, a human osteosarcoma cell line, were exposed to gamma-ray in irradiation room bearing 50,000 Ci 60 Co. After the irradiation, they were cultured for 24 h in the presence of cytochalasin B to block cytokinesis, cytoplasm and nucleus were stained with DAPI and propidium iodide, and the number of binuclear cells bearing micronuclei was determined by fluorescent microscopy. For proliferation inhibition, cells were cultured for 48 h after the irradiation and [3H] thymidine was pulsed for 4 h before harvesting. Dose-rate in the irradiation room was measured with photoluminescence dosimeter. While irradiation time less than 24 h did not affect dose-response curves for both biological responses, they were remarkably attenuated as exposure time increased to more than 7 days. These biological responses were dependent on dose-rate rather than dose when cells were irradiated for 30 days. Moreover, percentage of micronucleus-forming cells cultured continuously for more than 60 days at the constant dose-rate, was gradually decreased in spite of the total dose accumulation. These results suggest that biological responses at low dose-rate, are remarkably affected by exposure time, that they are dependent on dose-rate rather than total dose in the case of long-term irradiation, and that cells are getting resistant to radiation after the continuous irradiation for 2 months. It is necessary to include effect of irradiation time and dose-rate sufficiently to evaluate risk

  13. Weathering of a Roman Mosaic-A Biological and Quantitative Study on In Vitro Colonization of Calcareous Tesserae by Phototrophic Microorganisms.

    Directory of Open Access Journals (Sweden)

    Addolorata Marasco

    Full Text Available The potential impact of cyanobacteria and microalgae on the weathering of calcareous tesserae from a Roman mosaic of the II Century CE has been followed through in vitro experiments. Laboratory tests were carried out by inoculating mosaic tiles with single strains of Cyanobacteria or Chlorophyta to evaluate the roles of pioneer phototrophic microrganism on the resulting architecture of biofilms. The interaction between tesserae and strains was assessed at the whole substratum and micrometer scales, by image analysis and Confocal Laser Scanning (CLS microscopy, respectively. The biofilm surface coverage on each tessera varied from 19% (Fischerella ambigua to 97% (Microcoleus autumnalis. Cyanobacteria showed a better growth on calcareous tesserae, whereas the only green alga attaining a superficial coverage higher than 50% was Coelastrella rubescens. CLS microscopy evidenced two different types of spatial arrangement of the phototrophic organisms on the tesserae, that were defined as compact or porous, respectively. In the first one was measured a reduced number of empty spaces between cells or filaments, whereas in the second type, a reticulate texture allowed the presence of numerous empty volumes. The colonization processes observed are an intrinsic characteristic of each strain. We have proposed a colonization index IC as a sensible tool to describe, in a quantitative way, the pioneering attitude of each photosynthetic microorganism to colonize lithic substrates under laboratory conditions.

  14. Effects of Single and Combined Application of Organic, Biological and Chemical Fertilizers on Quantitative and Qualitative Yield of Coriander (Coriandrum sativum

    Directory of Open Access Journals (Sweden)

    M. Aghhavani Shajari

    2016-07-01

    Full Text Available Introduction: Medicinal plants were one of the main natural resources of Iran from ancient times. Coriander (Coriandrum sativum L. is from Apiaceae family that it has cultivated extensively in the world. Management and environmental factors such as nutritional management has a significant impact on the quantity and quality of plants. Application of organic fertilizers in conventional farming systems is not common and most of the nutritional need of plants supply through chemical fertilizers for short period. Excessive and unbalanced use of fertilizers in the long period, reduce crop yield and soil biological activity, accumulation of nitrates and heavy metals, and finally cause negative environmental effects and increase the cost of production. The use of bio-fertilizers and organic matter are taken into consideration to reduce the use of chemical fertilizers and increase the quality of most crops. Stability and soil fertility through the use of organic fertilizers are important due to having most of the elements required by plants and beneficial effects on physical, chemical, biological and soil fertility. Therefore, the aim of this research was to evaluate the effects of organic, biological and chemical fertilizers on quality and quantity characteristics of coriander. Materials and Methods: In order to study the effects of single and combined applications of organic, biological and chemical fertilizers on quantitative and qualitative characteristics of Coriander (Coriandrum sativum, an experiment was conducted based on a randomized complete block design with three replications and 12 treatments at Research Station, Faculty of Agriculture, Ferdowsi University of Mashhad, Iran, in - 2011. Treatments included: (1 mycorrhizae (Glomus mosseae (2 biosulfur (Thiobacillus sp., (3 chemical fertilizer (NPK, (4 cow manure, 5( vermin compost, 6( mycorrhizae + chemical fertilizer, 7( mycorrhizae + cow manure, 8( mycorrhizae + vermicompost, 9( biosulfur

  15. Interleaved quantitative BOLD: Combining extravascular R2' - and intravascular R2-measurements for estimation of deoxygenated blood volume and hemoglobin oxygen saturation.

    Science.gov (United States)

    Lee, Hyunyeol; Englund, Erin K; Wehrli, Felix W

    2018-03-23

    Quantitative BOLD (qBOLD), a non-invasive MRI method for assessment of hemodynamic and metabolic properties of the brain in the baseline state, provides spatial maps of deoxygenated blood volume fraction (DBV) and hemoglobin oxygen saturation (HbO 2 ) by means of an analytical model for the temporal evolution of free-induction-decay signals in the extravascular compartment. However, mutual coupling between DBV and HbO 2 in the signal model results in considerable estimation uncertainty precluding achievement of a unique set of solutions. To address this problem, we developed an interleaved qBOLD method (iqBOLD) that combines extravascular R 2 ' and intravascular R 2 mapping techniques so as to obtain prior knowledge for the two unknown parameters. To achieve these goals, asymmetric spin echo and velocity-selective spin-labeling (VSSL) modules were interleaved in a single pulse sequence. Prior to VSSL, arterial blood and CSF signals were suppressed to produce reliable estimates for cerebral venous blood volume fraction (CBV v ) as well as venous blood R 2 (to yield HbO 2 ). Parameter maps derived from the VSSL module were employed to initialize DBV and HbO 2 in the qBOLD processing. Numerical simulations and in vivo experiments at 3 T were performed to evaluate the performance of iqBOLD in comparison to the parent qBOLD method. Data obtained in eight healthy subjects yielded plausible values averaging 60.1 ± 3.3% for HbO 2 and 3.1 ± 0.5 and 2.0 ± 0.4% for DBV in gray and white matter, respectively. Furthermore, the results show that prior estimates of CBV v and HbO 2 from the VSSL component enhance the solution stability in the qBOLD processing, and thus suggest the feasibility of iqBOLD as a promising alternative to the conventional technique for quantifying neurometabolic parameters. Copyright © 2018. Published by Elsevier Inc.

  16. Determination of quantitative retention-activity relationships between pharmacokinetic parameters and biological effectiveness fingerprints of Salvia miltiorrhiza constituents using biopartitioning and microemulsion high-performance liquid chromatography.

    Science.gov (United States)

    Gao, Haoshi; Huang, Hongzhang; Zheng, Aini; Yu, Nuojun; Li, Ning

    2017-11-01

    In this study, we analyzed danshen (Salvia miltiorrhiza) constituents using biopartitioning and microemulsion high-performance liquid chromatography (MELC). The quantitative retention-activity relationships (QRARs) of the constituents were established to model their pharmacokinetic (PK) parameters and chromatographic retention data, and generate their biological effectiveness fingerprints. A high-performance liquid chromatography (HPLC) method was established to determine the abundance of the extracted danshen constituents, such as sodium danshensu, rosmarinic acid, salvianolic acid B, protocatechuic aldehyde, cryptotanshinone, and tanshinone IIA. And another HPLC protocol was established to determine the abundance of those constituents in rat plasma samples. An experimental model was built in Sprague Dawley (SD) rats, and calculated the corresponding PK parameterst with 3P97 software package. Thirty-five model drugs were selected to test the PK parameter prediction capacities of the various MELC systems and to optimize the chromatographic protocols. QRARs and generated PK fingerprints were established. The test included water/oil-soluble danshen constituents and the prediction capacity of the regression model was validated. The results showed that the model had good predictability. Copyright © 2017. Published by Elsevier B.V.

  17. Tested Studies for Laboratory Teaching. Proceedings of the Workshop/Conference of the Association for Biology Laboratory Education (ABLE) (15th, Toronto, Ontario, Canada, June 8-12, 1993). Volume 15.

    Science.gov (United States)

    Goldman, Corey A., Ed.

    The focus of the Association for Biology Laboratory Education (ABLE) is to improve the undergraduate biology laboratory experience by promoting the development and dissemination of interesting, innovative, and reliable laboratory exercises. This proceedings volume contains 18 papers: "Human DNA Fingerprinting by Polymerase Chain Reaction" (M. V.…

  18. Tested Studies for Laboratory Teaching. Proceedings of the Workshop/Conference of the Association for Biology Laboratory Education (ABLE) (13th, Laramie, Wyoming, June 11-15, 1991). Volume 13.

    Science.gov (United States)

    Goldman, Corey A., Ed.

    The focus of the Association for Biology Laboratory Education (ABLE) is to improve the undergraduate biology laboratory experience by promoting the development and dissemination of interesting, innovative, and reliable laboratory exercises. This proceedings volume contains 10 papers: "Testing Issues of Foraging and Flocking Behavior" (C. C.…

  19. West Hackberry Strategic Petroleum Reserve site brine-disposal monitoring, Year I report. Volume III. Biological oceanography. Final report

    Energy Technology Data Exchange (ETDEWEB)

    DeRouen, L.R.; Hann, R.W.; Casserly, D.M.; Giammona, C.; Lascara, V.J. (eds.)

    1983-02-01

    The Department of Energy's Strategic Petroleum Reserve Program began discharging brine into the Gulf of Mexico from its West Hackberry site near Cameron, Louisiana in May 1981. The brine originates from underground salt domes being leached with water from the Intracoastal Waterway, making available vast underground storage caverns for crude oil. The effects of brine discharge on aquatic organisms are presented in this volume. The topics covered are: benthos; nekton; phytoplankton; zooplankton; and data management.

  20. Normal tissue complication probabilities: dependence on choice of biological model and dose-volume histogram reduction scheme

    International Nuclear Information System (INIS)

    Moiseenko, Vitali; Battista, Jerry; Van Dyk, Jake

    2000-01-01

    Purpose: To evaluate the impact of dose-volume histogram (DVH) reduction schemes and models of normal tissue complication probability (NTCP) on ranking of radiation treatment plans. Methods and Materials: Data for liver complications in humans and for spinal cord in rats were used to derive input parameters of four different NTCP models. DVH reduction was performed using two schemes: 'effective volume' and 'preferred Lyman'. DVHs for competing treatment plans were derived from a sample DVH by varying dose uniformity in a high dose region so that the obtained cumulative DVHs intersected. Treatment plans were ranked according to the calculated NTCP values. Results: Whenever the preferred Lyman scheme was used to reduce the DVH, competing plans were indistinguishable as long as the mean dose was constant. The effective volume DVH reduction scheme did allow us to distinguish between these competing treatment plans. However, plan ranking depended on the radiobiological model used and its input parameters. Conclusions: Dose escalation will be a significant part of radiation treatment planning using new technologies, such as 3-D conformal radiotherapy and tomotherapy. Such dose escalation will depend on how the dose distributions in organs at risk are interpreted in terms of expected complication probabilities. The present study indicates considerable variability in predicted NTCP values because of the methods used for DVH reduction and radiobiological models and their input parameters. Animal studies and collection of standardized clinical data are needed to ascertain the effects of non-uniform dose distributions and to test the validity of the models currently in use

  1. Impact of 18FDG-PET/CT on biological target volume (BTV) definition for treatment planning for non-small cell lung cancer patients

    International Nuclear Information System (INIS)

    Devic, Slobodan; Tomic, Nada; Faria, Sergio; Dean, Geoffrey; Lisbona, Robert; Parker, William; Kaufman, Chris; Podgorsak, Ervin B.

    2007-01-01

    This work represents our effort to test feasibility of FDG-based PET/CT on target volume delineation in radiotherapy treatment planning of NSCLC patients. Different methods have been developed to enable more precise target outlining using PET: Qualitative Visual Method, CTV=2.5 SUV units, linear SUV threshold function method, and CTV=40% Iso of Maximum Uptake Value. We are proposing reconstruction of three biological target volumes: necrotic BTV (same as PTV created by radiation oncologist using CT data), proliferating BTV (based on PET signal to background ratio 1:3) and hypoxic BTV (based on PET signal to background ratio of 1:19). Two IMRT plans were created and compared to the conventional treatment plan: 'conservative' IMRT plan delivers 52.5 Gy to the necrotic BTV and 65 Gy to the hypoxic BTV; 'radical' IMRT plan delivers 30 Gy to necrotic BTV, 52.5 Gy to proliferating BTV and 65 Gy to hypoxic BTV. Use of BTVs in IMRT plans is attractive because it increases dose to targets considered to need higher doses. It reduces considerably dose to heart and spinal cord, organs considered to limit dose escalation approaches in NSCLC treatment. 'Conservative' IMRT approach can be understood as a PET/CT-based concomitant boost to the tumor expressing the highest FDG uptake. 'Radical' plan implies deviation from the traditional uniform dose target coverage approach, with the intention of achieving better surrounding tissue sparing and ultimately allowing for dose escalation protocols relying on biologically based treatment planning

  2. Effects of reduced return activated sludge flows and volume on anaerobic zone performance for a septic wastewater biological phosphorus removal system.

    Science.gov (United States)

    Magro, Daniel; Elias, Steven L; Randall, Andrew Amis

    2005-01-01

    Enhanced biological phosphorous removal (EBPR) performance was found to be adequate with reduced return-activated sludge (RAS) flows (50% of available RAS) to the anaerobic tank and smaller-than-typical anaerobic zone volume (1.08 hours hydraulic retention time [HRT]). Three identical parallel biological nutrient removal pilot plants were fed with strong, highly fermented (160 mg/L volatile fatty acids [VFAs]), domestic and industrial wastewater from a full-scale wastewater treatment facility. The pilot plants were operated at 100, 50, 40, and 25% RAS (percent of available RAS) flows to the anaerobic tank, with the remaining RAS to the anoxic tank. In addition, varying anaerobic HRT (1.08 and 1.5 hours) and increased hydraulic loading (35% increase) were examined. The study was divided into four phases, and the effect of these process variations on EBPR were studied by having one different variable between two identical systems. The most significant conclusion was that returning part of the RAS to the anaerobic zone did not decrease EBPR performance; instead, it changed the location of phosphorous release and uptake. Bringing less RAS to the anaerobic and more to the anoxic tank decreased anaerobic phosphorus release and increased anoxic phosphorus release (or decreased anoxic phosphorus uptake). Equally important is that, with VFA-rich influent wastewater, excessive anaerobic volume was shown to hurt overall phosphorus removal, even when it resulted in increased anaerobic phosphorus release.

  3. Quantitative method of viral pollution determination for large volume of water using ferric hydroxide gel impregnated on the surface of glassfibre cartridge

    Directory of Open Access Journals (Sweden)

    Akira Homma

    1974-01-01

    Full Text Available Quantitative method of viral pollution determination for large volume of water using ferric hydroxide gel impregnated on the surface of glassfibre cartridge filter. The use of ferric hydroxide gel, impregnated on the surface of glassfibre cartridge filter enable us to recover 62.5% of virus (Poliomylitis type I, Lsc strain exsogeneously added to 400 liters of tap-water. The virus concentrator system consists of four cartridge filters, in which the three first one are clarifiers, where the contaminants are removed physically, without significant virus loss at this stage. The last cartridge filter is impregnated with ferric hydroxide gel, where the virus is adsorbed. After the required volume of water has been processed, the last filter is removed from the system and the viruses are recovered from the gel, using 1 liter of glycine/NaOH buffer, at pH 11. Immediately the eluate is clarified through series of cellulose acetate membranes mounted in a 142mm Millipore filter. For the second step of virus concentration, HC1 1N is added slowly to the eluate to achieve pH 3.5-4. MgC1, is added to give a final concentration of 0.05M and the viruses are readsorbed on a 0.45 , porosity (HA cellulose acetate membrane, mounted in a 90 mm Millipore filter. The viruses are recovered using the same eluent plus 10% of fetal calf serum, to a final volume of 3 ml. In this way, it was possible to concentrate virus from 400 liters of tap-water, into 1 liter in the first stage of virus concentration and just to 3 ml of final volume in a second step. The efficiency, simplicity and low operational cost, provded by the method, make it feasible to study viral pollution of recreational and tap-water sources.Relata-se o emprego de um concentrador portátil, o qual se mostrou capaz de recuperar 62,5% dos vírus (Polio I, amostra Lsc experimentalmente dispersos em 400 litros de água, os quais foram reduzidos a 3 ml. O sistema concentrador de vírus é composto de quatro

  4. The impact of 3D volume of interest definition on accuracy and precision of activity estimation in quantitative SPECT and planar processing methods

    Science.gov (United States)

    He, Bin; Frey, Eric C.

    2010-06-01

    Accurate and precise estimation of organ activities is essential for treatment planning in targeted radionuclide therapy. We have previously evaluated the impact of processing methodology, statistical noise and variability in activity distribution and anatomy on the accuracy and precision of organ activity estimates obtained with quantitative SPECT (QSPECT) and planar (QPlanar) processing. Another important factor impacting the accuracy and precision of organ activity estimates is accuracy of and variability in the definition of organ regions of interest (ROI) or volumes of interest (VOI). The goal of this work was thus to systematically study the effects of VOI definition on the reliability of activity estimates. To this end, we performed Monte Carlo simulation studies using randomly perturbed and shifted VOIs to assess the impact on organ activity estimates. The 3D NCAT phantom was used with activities that modeled clinically observed 111In ibritumomab tiuxetan distributions. In order to study the errors resulting from misdefinitions due to manual segmentation errors, VOIs of the liver and left kidney were first manually defined. Each control point was then randomly perturbed to one of the nearest or next-nearest voxels in three ways: with no, inward or outward directional bias, resulting in random perturbation, erosion or dilation, respectively, of the VOIs. In order to study the errors resulting from the misregistration of VOIs, as would happen, e.g. in the case where the VOIs were defined using a misregistered anatomical image, the reconstructed SPECT images or projections were shifted by amounts ranging from -1 to 1 voxels in increments of with 0.1 voxels in both the transaxial and axial directions. The activity estimates from the shifted reconstructions or projections were compared to those from the originals, and average errors were computed for the QSPECT and QPlanar methods, respectively. For misregistration, errors in organ activity estimations were

  5. The impact of 3D volume of interest definition on accuracy and precision of activity estimation in quantitative SPECT and planar processing methods

    Energy Technology Data Exchange (ETDEWEB)

    He Bin [Division of Nuclear Medicine, Department of Radiology, New York Presbyterian Hospital-Weill Medical College of Cornell University, New York, NY 10021 (United States); Frey, Eric C, E-mail: bih2006@med.cornell.ed, E-mail: efrey1@jhmi.ed [Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, Baltimore, MD 21287-0859 (United States)

    2010-06-21

    Accurate and precise estimation of organ activities is essential for treatment planning in targeted radionuclide therapy. We have previously evaluated the impact of processing methodology, statistical noise and variability in activity distribution and anatomy on the accuracy and precision of organ activity estimates obtained with quantitative SPECT (QSPECT) and planar (QPlanar) processing. Another important factor impacting the accuracy and precision of organ activity estimates is accuracy of and variability in the definition of organ regions of interest (ROI) or volumes of interest (VOI). The goal of this work was thus to systematically study the effects of VOI definition on the reliability of activity estimates. To this end, we performed Monte Carlo simulation studies using randomly perturbed and shifted VOIs to assess the impact on organ activity estimates. The 3D NCAT phantom was used with activities that modeled clinically observed {sup 111}In ibritumomab tiuxetan distributions. In order to study the errors resulting from misdefinitions due to manual segmentation errors, VOIs of the liver and left kidney were first manually defined. Each control point was then randomly perturbed to one of the nearest or next-nearest voxels in three ways: with no, inward or outward directional bias, resulting in random perturbation, erosion or dilation, respectively, of the VOIs. In order to study the errors resulting from the misregistration of VOIs, as would happen, e.g. in the case where the VOIs were defined using a misregistered anatomical image, the reconstructed SPECT images or projections were shifted by amounts ranging from -1 to 1 voxels in increments of with 0.1 voxels in both the transaxial and axial directions. The activity estimates from the shifted reconstructions or projections were compared to those from the originals, and average errors were computed for the QSPECT and QPlanar methods, respectively. For misregistration, errors in organ activity estimations

  6. Leo Szilard Lectureship Award Talk - Universal Scaling Laws from Cells to Cities; A Physicist's Search for Quantitative, Unified Theories of Biological and Social Structure and Dynamics

    Science.gov (United States)

    West, Geoffrey

    2013-04-01

    Many of the most challenging, exciting and profound questions facing science and society, from the origins of life to global sustainability, fall under the banner of ``complex adaptive systems.'' This talk explores how scaling can be used to begin to develop physics-inspired quantitative, predictive, coarse-grained theories for understanding their structure, dynamics and organization based on underlying mathematisable principles. Remarkably, most physiological, organisational and life history phenomena in biology and socio-economic systems scale in a simple and ``universal'' fashion: metabolic rate scales approximately as the 3/4-power of mass over 27 orders of magnitude from complex molecules to the largest organisms. Time-scales (such as lifespans and growth-rates) and sizes (such as genome lengths and RNA densities) scale with exponents which are typically simple multiples of 1/4, suggesting that fundamental constraints underlie much of the generic structure and dynamics of living systems. These scaling laws follow from dynamical and geometrical properties of space-filling, fractal-like, hierarchical branching networks, presumed optimised by natural selection. This leads to a general framework that potentially captures essential features of diverse systems including vasculature, ontogenetic growth, cancer, aging and mortality, sleep, cell size, and DNA nucleotide substitution rates. Cities and companies also scale: wages, profits, patents, crime, disease, pollution, road lengths scale similarly across the globe, reflecting underlying universal social network dynamics which point to general principles of organization transcending their individuality. These have dramatic implications for global sustainability: innovation and wealth creation that fuel social systems, left unchecked, potentially sow the seeds for their inevitable collapse.

  7. Changes in synovial membrane and joint effusion volumes after intraarticular methylprednisolone. Quantitative assessment of inflammatory and destructive changes in arthritis by MRI

    DEFF Research Database (Denmark)

    Østergaard, Mikkel; Stoltenberg, M; Gideon, P

    1996-01-01

    OBJECTIVE: To evaluate synovial membrane volumes, effusion volumes, and cartilage and bone erosion scores determined by magnetic resonance imaging (MRI) as markers of disease activity and severity in arthritis. METHODS: Gadolinium-DTPA enhanced MRI of 18 arthritic knees was performed before and 1......, 7, 30 and 180 days after intraarticular methylprednisolone injection until clinical relapse. Intraobserver, interobserver, and inter-MRI variations were determined from 2 successive MRI of another 6 knees. RESULTS: In all knees synovial membrane and effusion volumes decreased within the first...... posttreatment week (median decrease 49 and 65%, respectively), and remained low during remission. Synovial volumes, but not effusion volumes, increased to pretreatment levels in case of clinical relapse, indicating that synovial volumes were most important to the clinical appearance. The intraobserver...

  8. Quantitative evaluation of high intensity signal on MIP images of carotid atherosclerotic plaques from routine TOF-MRA reveals elevated volumes of intraplaque hemorrhage and lipid rich necrotic core.

    Science.gov (United States)

    Yamada, Kiyofumi; Song, Yan; Hippe, Daniel S; Sun, Jie; Dong, Li; Xu, Dongxiang; Ferguson, Marina S; Chu, Baocheng; Hatsukami, Thomas S; Chen, Min; Zhou, Cheng; Yuan, Chun

    2012-11-29

    Carotid intraplaque hemorrhage (IPH) and lipid rich necrotic core (LRNC) have been associated with accelerated plaque growth, luminal narrowing, future surface disruption and development of symptomatic events. The aim of this study was to evaluate the quantitative relationships between high intensity signals (HIS) in the plaque on TOF-MRA and IPH or LRNC volumes as measured by multicontrast weighted CMR. Seventy six patients with a suspected carotid artery stenosis or carotid plaque by ultrasonography underwent multicontrast carotid CMR. HIS presence and volume were measured from TOF-MRA MIP images while IPH and LRNC volumes were separately measured from multicontrast CMR. For detecting IPH, HIS on MIP images overall had high specificity (100.0%, 95% CI: 93.0 - 100.0%) but relatively low sensitivity (32%, 95% CI: 20.8 - 47.9%). However, the sensitivity had a significant increasing relationship with underlying IPH volume (p = 0.033) and degree of stenosis (p = 0.022). Mean IPH volume was 2.7 times larger in those with presence of HIS than in those without (142.8 ± 97.7 mm(3) vs. 53.4 ± 56.3 mm(3), p = 0.014). Similarly, mean LRNC volume was 3.4 times larger in those with HIS present (379.8 ± 203.4 mm(3) vs. 111.3 ± 122.7 mm(3), p = 0.001). There was a strong correlation between the volume of the HIS region and the IPH volume measured from multicontrast CMR (r = 0.96, p routine, clinical TOF sequences. High intensity signals in carotid plaque on TOF-MRA MIP images are associated with increased intraplaque hemorrhage and lipid-rich necrotic core volumes. The technique is most sensitive in patients with moderate to severe stenosis.

  9. Health-related quality of life of Portuguese children and adolescents according to their biological maturation and volume of physical activity.

    Science.gov (United States)

    Garcia, Catarina; Teles, Júlia; Barrigas, Carlos; Fragoso, Isabel

    2018-06-01

    The purpose of this study was to analyze the relationship between biological maturation and health-related quality of life (HRQoL) in Portuguese children and adolescents of both sexes when the effect of chronological age (CA) and volume of physical activity (VPA) were removed. HRQoL, biological maturation, CA, and VPA were assessed in 750 children and adolescents, 11-17 years old, from 3 schools in Lisbon, Portugal. The KIDSCREEN-52 was used to assess HRQoL. Maturity indicator was bone age (BA), using Tanner-Whitehouse III method (TW3). The participants were classified into three different maturity categories: late, on time, and early maturers. VPA was assessed by questionnaire (RAPIL II). An analysis of covariance (ANCOVA), using the CA and the VPA as covariates was completed. The level of significance was set at p ≤ 0.05. Analysis of covariance suggested an influence of biological maturation in physical well-being dimension in both sexes, with early-maturing girls and boys having worst perception. Maturity groups were also influent in moods and emotions for girls. CA seems to be particularly important in self-perception and parent relation and home life for girls and in school environment for boys. Biological maturation and CA have relevant impact on some HRQoL dimensions. These variables, due to their nature and effect should be considered particularly when working with specific domains of HRQoL as physical well-being in both sexes, moods and emotions and self-perception and parent relation and home life for girls and in school environment for boys.

  10. Changes in synovial membrane and joint effusion volumes after intraarticular methylprednisolone. Quantitative assessment of inflammatory and destructive changes in arthritis by MRI

    DEFF Research Database (Denmark)

    Østergaard, Mikkel; Stoltenberg, M; Gideon, P

    1996-01-01

    OBJECTIVE: To evaluate synovial membrane volumes, effusion volumes, and cartilage and bone erosion scores determined by magnetic resonance imaging (MRI) as markers of disease activity and severity in arthritis. METHODS: Gadolinium-DTPA enhanced MRI of 18 arthritic knees was performed before and 1...

  11. Liver volume, intrahepatic fat and body weight in the course of a lifestyle interventional study. Analysis with quantitative MR-based methods

    International Nuclear Information System (INIS)

    Bongers, M.N.; Stefan, N.; Fritsche, A.; Haering, H.U.; Nikolaou, K.; Schick, F.; Machann, J.

    2015-01-01

    The aim of this study was to investigate potential associations between changes in liver volume, the amount of intrahepatic lipids (IHL) and body weight during lifestyle interventions. In a prospective study 150 patients with an increased risk for developing type 2 diabetes mellitus were included who followed a caloric restriction diet for 6 months. In the retrospective analysis 18 women and 9 men (age range 22-71 years) with an average body mass index (BMI) of 32 kg/m 2 were enrolled. The liver volume was determined at the beginning and after 6 months by three-dimensional magnetic resonance imaging (3D-MRI, echo gradient, opposed-phase) and IHLs were quantified by volume-selective MR spectroscopy in single voxel stimulated echo acquisition mode (STEAM). Univariable and multivariable correlation analyses between changes of liver volume (Δliver volume), intrahepatic lipids (ΔIHL) and body weight (ΔBW) were performed. Univariable correlation analysis in the whole study cohort showed associations between ΔIHL and ΔBW (r = 0.69; p < 0.0001), ΔIHL and Δliver volume (r = 0.66; p = 0.0002) as well as ΔBW and Δliver volume (r = 0.5; p = 0.0073). Multivariable correlation analysis revealed that changes of liver volume are primarily determined by changes in IHL independent of changes in body weight (β = 0.0272; 95 % CI: 0.0155-0.034; p < 0.0001). Changes of liver volume during lifestyle interventions are independent of changes of body weight primarily determined by changes of IHL. These results show the reversibility of augmented liver volume in steatosis if it is possible to reduce IHLs during lifestyle interventions. (orig.) [de

  12. Multivariate imaging-genetics study of MRI gray matter volume and SNPs reveals biological pathways correlated with brain structural differences in Attention Deficit Hyperactivity Disorder

    Directory of Open Access Journals (Sweden)

    Sabin Khadka

    2016-07-01

    Full Text Available Background: Attention Deficit Hyperactivity Disorder (ADHD is a prevalent neurodevelopmental disorder affecting children, adolescents, and adults. Its etiology is not well-understood, but it is increasingly believed to result from diverse pathophysiologies that affect the structure and function of specific brain circuits. Although one of the best-studied neurobiological abnormalities in ADHD is reduced fronto-striatal-cerebellar gray matter volume, its specific genetic correlates are largely unknown. Methods: In this study, T1-weighted MR images of brain structure were collected from 198 adolescents (63 ADHD-diagnosed. A multivariate parallel independent component analysis technique (Para-ICA identified imaging-genetic relationships between regional gray matter volume and single nucleotide polymorphism data. Results: Para-ICA analyses extracted 14 components from genetic data and 9 from MR data. An iterative cross-validation using randomly-chosen sub-samples indicated acceptable stability of these ICA solutions. A series of partial correlation analyses controlling for age, sex, and ethnicity revealed two genotype-phenotype component pairs significantly differed between ADHD and non-ADHD groups, after a Bonferroni correction for multiple comparisons. The brain phenotype component not only included structures frequently found to have abnormally low volume in previous ADHD studies, but was also significantly associated with ADHD differences in symptom severity and performance on cognitive tests frequently found to be impaired in patients diagnosed with the disorder. Pathway analysis of the genotype component identified several different biological pathways linked to these structural abnormalities in ADHD. Conclusions: Some of these pathways implicate well-known dopaminergic neurotransmission and neurodevelopment hypothesized to be abnormal in ADHD. Other more recently implicated pathways included glutamatergic and GABA-eric physiological systems

  13. Dose-volume and biological-model based comparison between helical tomotherapy and (inverse-planned) IMAT for prostate tumours

    International Nuclear Information System (INIS)

    Iori, Mauro; Cattaneo, Giovanni Mauro; Cagni, Elisabetta; Fiorino, Claudio; Borasi, Gianni; Riccardo, Calandrino; Iotti, Cinzia; Fazio, Ferruccio; Nahum, Alan E.

    2008-01-01

    Background and purpose: Helical tomotherapy (HT) and intensity-modulated arc therapy (IMAT) are two arc-based approaches to the delivery of intensity-modulated radiotherapy (IMRT). Through plan comparisons we have investigated the potential of IMAT, both with constant (conventional or IMAT-C) and variable (non-conventional or IMAT-NC, a theoretical exercise) dose-rate, to serve as an alternative to helical tomotherapy. Materials and methods: Six patients with prostate tumours treated by HT with a moderately hypo-fractionated protocol, involving a simultaneous integrated boost, were re-planned as IMAT treatments. A method for IMAT inverse-planning using a commercial module for static IMRT combined with a multi-leaf collimator (MLC) arc-sequencing was developed. IMAT plans were compared to HT plans in terms of dose statistics and radiobiological indices. Results: Concerning the planning target volume (PTV), the mean doses for all PTVs were similar for HT and IMAT-C plans with minimum dose, target coverage, equivalent uniform dose (EUD) and tumour control probability (TCP) values being generally higher for HT; maximum dose and degree of heterogeneity were instead higher for IMAT-C. In relation to organs at risk, mean doses and normal tissue complication probability (NTCP) values were similar between the two modalities, except for the penile bulb where IMAT was significantly better. Re-normalizing all plans to the same rectal toxicity (NTCP = 5%), the HT modality yielded higher TCP than IMAT-C but there was no significant difference between HT and IMAT-NC. The integral dose with HT was higher than that for IMAT. Conclusions: with regards to the plan analysis, the HT is superior to IMAT-C in terms of target coverage and dose homogeneity within the PTV. Introducing dose-rate variation during arc-rotation, not deliverable with current linac technology, the simulations result in comparable plan indices between (IMAT-NC) and HT

  14. Development of Quantitative Real-Time PCR Assays for Detection and Quantification of Surrogate Biological Warfare Agents in Building Debris and Leachate▿

    Science.gov (United States)

    Saikaly, Pascal E.; Barlaz, Morton A.; de los Reyes, Francis L.

    2007-01-01

    Evaluation of the fate and transport of biological warfare (BW) agents in landfills requires the development of specific and sensitive detection assays. The objective of the current study was to develop and validate SYBR green quantitative real-time PCR (Q-PCR) assays for the specific detection and quantification of surrogate BW agents in synthetic building debris (SBD) and leachate. Bacillus atrophaeus (vegetative cells and spores) and Serratia marcescens were used as surrogates for Bacillus anthracis (anthrax) and Yersinia pestis (plague), respectively. The targets for SYBR green Q-PCR assays were the 16S-23S rRNA intergenic transcribed spacer (ITS) region and recA gene for B. atrophaeus and the gyrB, wzm, and recA genes for S. marcescens. All assays showed high specificity when tested against 5 ng of closely related Bacillus and Serratia nontarget DNA from 21 organisms. Several spore lysis methods that include a combination of one or more of freeze-thaw cycles, chemical lysis, hot detergent treatment, bead beat homogenization, and sonication were evaluated. All methods tested showed similar threshold cycle values. The limit of detection of the developed Q-PCR assays was determined using DNA extracted from a pure bacterial culture and DNA extracted from sterile water, leachate, and SBD samples spiked with increasing quantities of surrogates. The limit of detection for B. atrophaeus genomic DNA using the ITS and B. atrophaeus recA Q-PCR assays was 7.5 fg per PCR. The limits of detection of S. marcescens genomic DNA using the gyrB, wzm, and S. marcescens recA Q-PCR assays were 7.5 fg, 75 fg, and 7.5 fg per PCR, respectively. Quantification of B. atrophaeus vegetative cells and spores was linear (R2 > 0.98) over a 7-log-unit dynamic range down to 101 B. atrophaeus cells or spores. Quantification of S. marcescens (R2 > 0.98) was linear over a 6-log-unit dynamic range down to 102 S. marcescens cells. The developed Q-PCR assays are highly specific and sensitive and can

  15. Fusion of biological membranes

    Indian Academy of Sciences (India)

    Home; Journals; Pramana – Journal of Physics; Volume 64; Issue 6. Fusion of biological membranes. K Katsov M Müller M Schick. Invited Talks:- Topic 11. Biologically motivated problems (protein-folding models, dynamics at the scale of the cell; biological networks, evolution models, etc.) Volume 64 Issue 6 June 2005 pp ...

  16. Quantitative dose-volume response analysis of changes in parotid gland function after radiotherapy in the head-and-neck region

    International Nuclear Information System (INIS)

    Roesink, Judith M.; Moerland, Marinus A.; Battermann, Jan J.; Hordijk, Gerrit Jan; Terhaard, Chris H.J.

    2001-01-01

    Purpose: To study the radiation tolerance of the parotid glands as a function of dose and volume irradiated. Methods and Materials: One hundred eight patients treated with primary or postoperative radiotherapy for various malignancies in the head-and-neck region were prospectively evaluated. Stimulated parotid flow rate was measured before radiotherapy and 6 weeks, 6 months, and 1 year after radiotherapy. Parotid gland dose-volume histograms were derived from CT-based treatment planning. The normal tissue complication probability model proposed by Lyman was fit to the data. A complication was defined as stimulated parotid flow rate 50 (the dose to the whole organ leading to a complication probability of 50%) was found to be 31, 35, and 39 Gy at 6 weeks, 6 months, and 1 year postradiotherapy, respectively. The volume dependency parameter n was around 1, which means that the mean parotid dose correlates best with the observed complications. There was no steep dose-response curve (m=0.45 at 1 year postradiotherapy). Conclusions: This study on dose/volume/parotid gland function relationships revealed a linear correlation between postradiotherapy flow ratio and parotid gland dose and a strong volume dependency. No threshold dose was found. Recovery of parotid gland function was shown at 6 months and 1 year after radiotherapy. In radiation planning, attempts should be made to achieve a mean parotid gland dose at least below 39 Gy (leading to a complication probability of 50%)

  17. Multi-detector CT urography: effect of oral hydration and contrast medium volume on renal parenchymal enhancement and urinary tract opacification - a quantitative and qualitative analysis

    International Nuclear Information System (INIS)

    Szolar, Dieter H.; Tillich, Manfred; Preidler, Klaus W.

    2010-01-01

    To assess the effect of oral hydration and contrast-medium volume on renal enhancement and urinary tract opacification in multi-detector CT urography. A total of 192 patients were assigned to different protocols with varying doses of contrast agent with and without oral hydration. The attenuation was measured in the renal parenchyma in the unenhanced, nephrographic and excretory phase, and in the urinary tract in excretory phase imaging, respectively. Opacification of the urinary tract was graded on volume rendered images. Oral hydration did not significantly alter renal parenchymal enhancement in both the nephrographic and the excretory phase (p > 0.001), but significantly decreased mean attenuation of the urinary tract in the excretory phase (p ≤ 0.001), and improved continuous opacification of all ureter segments (p < 0.01). Higher volumes of contrast medium improved renal parenchymal enhancement (p ≤ 0.001) and continuous opacification of the urinary tract (p ≤ 0.01). Oral hydration leads to lower attenuation values in the urinary tract but improves the continuous opacification of the tract. Increase in contrast medium volume leads to higher renal parenchymal enhancement as well as to an increased continuous opacification of the urinary tract. Decrease in contrast medium volume cannot be compensated for by oral hydration in terms of parenchymal enhancement. (orig.)

  18. Comparison of Quantitative Analysis of Image Logs for Shale Volume and Net to Gross Calculation of a Thinly Laminated Reservoir between VNG-NERGE and LAGIA-EGYPT

    Directory of Open Access Journals (Sweden)

    Ahmed Z. Nooh

    2017-09-01

    The gamma ray log data resolution is considerably lower than the FMI log to reflect accurate lithology changes in thinly bedded reservoirs. It has been found afterthought some calibrations and corrections on the FMI resistivity log, the new processed log is used for clay volume and net to gross calculation of the reservoir, indicating the potential of this log for analysis of thin beds. A comparison between VNG-NERGE, NORTH SEA WELL, NERWING and LAGIA-8, LAGIA, EGYPT indicates the calculation for shale volume at different intervals using FMI tools.

  19. Quantitative evaluation of high intensity signal on MIP images of carotid atherosclerotic plaques from routine TOF-MRA reveals elevated volumes of intraplaque hemorrhage and lipid rich necrotic core

    Directory of Open Access Journals (Sweden)

    Yamada Kiyofumi

    2012-11-01

    Full Text Available Abstract Background Carotid intraplaque hemorrhage (IPH and lipid rich necrotic core (LRNC have been associated with accelerated plaque growth, luminal narrowing, future surface disruption and development of symptomatic events. The aim of this study was to evaluate the quantitative relationships between high intensity signals (HIS in the plaque on TOF-MRA and IPH or LRNC volumes as measured by multicontrast weighted CMR. Methods Seventy six patients with a suspected carotid artery stenosis or carotid plaque by ultrasonography underwent multicontrast carotid CMR. HIS presence and volume were measured from TOF-MRA MIP images while IPH and LRNC volumes were separately measured from multicontrast CMR. Results For detecting IPH, HIS on MIP images overall had high specificity (100.0%, 95% CI: 93.0 – 100.0% but relatively low sensitivity (32%, 95% CI: 20.8 – 47.9%. However, the sensitivity had a significant increasing relationship with underlying IPH volume (p = 0.033 and degree of stenosis (p = 0.022. Mean IPH volume was 2.7 times larger in those with presence of HIS than in those without (142.8 ± 97.7 mm3 vs. 53.4 ± 56.3 mm3, p = 0.014. Similarly, mean LRNC volume was 3.4 times larger in those with HIS present (379.8 ± 203.4 mm3 vs. 111.3 ± 122.7 mm3, p = 0.001. There was a strong correlation between the volume of the HIS region and the IPH volume measured from multicontrast CMR (r = 0.96, p  Conclusion MIP images are easily reformatted from three minute, routine, clinical TOF sequences. High intensity signals in carotid plaque on TOF-MRA MIP images are associated with increased intraplaque hemorrhage and lipid-rich necrotic core volumes. The technique is most sensitive in patients with moderate to severe stenosis.

  20. Hippocampal volume change measurement: Quantitative assessment of the reproducibility of expert manual outlining and the automated methods FreeSurfer and FIRST

    NARCIS (Netherlands)

    Mulder, E.R.; de Jong, R.A.; Knol, D.L.; van Schijndel, R.A.; Cover, K.S.; Visser, P.J.; Barkhof, F.; Vrenken, H.

    2014-01-01

    Background: To measure hippocampal volume change in Alzheimer's disease (AD) or mild cognitive impairment (MCI), expert manual delineation is often used because of its supposed accuracy. It has been suggested that expert outlining yields poorer reproducibility as compared to automated methods, but

  1. Potentiometric titration in a low volume of solution for rapid assay of uranium. Application to quantitative electro-reduction of uranium(VI)

    International Nuclear Information System (INIS)

    Sahoo, P.; Ananthanarayanan, R.; Murali, N.; Mallika, C.; Falix Lawrence; Kamachi Mudali, U.

    2012-01-01

    A simple, inexpensive PC based potentiometric titration technique for the assay of uranium using low volumes of sample aliquot (25-100 μL) along with all reagents (total volume of solution being less than 2.5 mL) is presented. The technique involves modification of the well known Davies and Gray Method recommended for assay of uranium(VI) in nuclear materials by introducing an innovative potentiometric titration device with a mini cell developed in-house. After appropriate chemical conditioning the titration is completed within a couple of minutes with display of online titration plot showing the progress of titration. The first derivative plot generated immediately after titration provides information of end point. The main advantage of using this technique is to carry out titration with minimum volumes of sample and reagents generating minimum volume of wastes after titration. The validity of the technique was evaluated using standard certified samples. This technique was applied for assay of uranium in a typical sample collected from fuel reprocessing laboratory. Further, the present technique was deployed in investigating the optimum conditions for efficient in situ production of U(IV). The precision in the estimation of uranium is highly satisfactory (RSD less than 1.0%). (author)

  2. Biological basis of detoxication

    National Research Council Canada - National Science Library

    Caldwell, John; Jakoby, William B

    1983-01-01

    This volume considers that premise that most of the major patterns of biological conversion of foreign compounds are known and may have predictive value in assessing the biological course for novel compounds...

  3. The influence of biological and technical factors on quantitative analysis of amyloid PET: Points to consider and recommendations for controlling variability in longitudinal data.

    Science.gov (United States)

    Schmidt, Mark E; Chiao, Ping; Klein, Gregory; Matthews, Dawn; Thurfjell, Lennart; Cole, Patricia E; Margolin, Richard; Landau, Susan; Foster, Norman L; Mason, N Scott; De Santi, Susan; Suhy, Joyce; Koeppe, Robert A; Jagust, William

    2015-09-01

    In vivo imaging of amyloid burden with positron emission tomography (PET) provides a means for studying the pathophysiology of Alzheimer's and related diseases. Measurement of subtle changes in amyloid burden requires quantitative analysis of image data. Reliable quantitative analysis of amyloid PET scans acquired at multiple sites and over time requires rigorous standardization of acquisition protocols, subject management, tracer administration, image quality control, and image processing and analysis methods. We review critical points in the acquisition and analysis of amyloid PET, identify ways in which technical factors can contribute to measurement variability, and suggest methods for mitigating these sources of noise. Improved quantitative accuracy could reduce the sample size necessary to detect intervention effects when amyloid PET is used as a treatment end point and allow more reliable interpretation of change in amyloid burden and its relationship to clinical course. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  4. Quantitative in vivo assessment of radiation injury of the liver using Gd-EOB-DTPA enhanced MRI: tolerance dose of small liver volumes

    Directory of Open Access Journals (Sweden)

    Pech Maciej

    2011-04-01

    Full Text Available Abstract Backround Hepatic radiation toxicity restricts irradiation of liver malignancies. Better knowledge of hepatic tolerance dose is favourable to gain higher safety and to optimize radiation regimes in radiotherapy of the liver. In this study we sought to determine the hepatic tolerance dose to small volume single fraction high dose rate irradiation. Materials and methods 23 liver metastases were treated by CT-guided interstitial brachytherapy. MRI was performed 3 days, 6, 12 and 24 weeks after therapy. MR-sequences were conducted with T1-w GRE enhanced by hepatocyte-targeted Gd-EOB-DTPA. All MRI data sets were merged with 3D-dosimetry data. The reviewer indicated the border of hypointensity on T1-w images (loss of hepatocyte function or hyperintensity on T2-w images (edema. Based on the volume data, a dose-volume-histogram was calculated. We estimated the threshold dose for edema or function loss as the D90, i.e. the dose achieved in at least 90% of the pseudolesion volume. Results At six weeks post brachytherapy, the hepatocyte function loss reached its maximum extending to the former 9.4Gy isosurface in median (i.e., ≥9.4Gy dose exposure led to hepatocyte dysfunction. After 12 and 24 weeks, the dysfunctional volume had decreased significantly to a median of 11.4Gy and 14Gy isosurface, respectively, as a result of repair mechanisms. Development of edema was maximal at six weeks post brachytherapy (9.2Gy isosurface in median, and regeneration led to a decrease of the isosurface to a median of 11.3Gy between 6 and 12 weeks. The dose exposure leading to hepatocyte dysfunction was not significantly different from the dose provoking edema. Conclusion Hepatic injury peaked 6 weeks after small volume irradiation. Ongoing repair was observed up to 6 months. Individual dose sensitivity may differ as demonstrated by a relatively high standard deviation of threshold values in our own as well as all other published data.

  5. X-ray cone beam microtomography for quantitative assessment of tracheal and pharyngeal volumes of Rhodnius prolixus; Utilizacao da microtomografia computadorizada com feixe de raios-X conico para a determinacao quantitativa do volume da traqueia e faringe do Rhodnius prolixus

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Izabella Soares de

    2017-07-01

    In the past decade microcomputerized tomography imaging using synchrotron radiation has become a powerful technique to generate high resolution images of Rhodinus prolixus. Images of soft tissues (protocerebrum and muscles) and dense structures (pharynx, trachea and esophagus) of R. prolixus head have been obtained using synchrotron radiation microtomography in mono and polychromatic configuration, respectively. Advancements in conventional microtomography have increased the achievable resolution and contrast, making this relatively inexpensive and widely available technology potentially useful for studies of insect internal morphology. The main goal of this work was to provide a new set of high quality microtomographic images of R. prolixus achieved by means of a desktop X-ray microtomograph. It allows the three-dimensional visualization of important chitinized structures: pharynx and tracheae. Pharyngeal and tracheal volumes were quantitatively evaluated at different days (1, 4, 10, 15 and 20) after feeding. The results suggest that variation of average volumes could be attributed to insect hormone 20-hydroxy-ecdysone (20-OH-Ec) pulse at 11 days after feeding. Pharyngeal volumes decrease 3.80 times. On the other hand, tracheal volumes increase 1.78 times. Head total volume showed similar trends than trachea. (author)

  6. Superolateral Hoffa's fat pad (SHFP) oedema and patellar cartilage volume loss: quantitative analysis using longitudinal data from the Foundation for the National Institute of Health (FNIH) Osteoarthritis Biomarkers Consortium.

    Science.gov (United States)

    Haj-Mirzaian, Arya; Guermazi, Ali; Hafezi-Nejad, Nima; Sereni, Christopher; Hakky, Michael; Hunter, David J; Zikria, Bashir; Roemer, Frank W; Demehri, Shadpour

    2018-04-12

    To determine the association of superolateral Hoffa's fat pad (SHFP) oedema and patellofemoral joint structural damage in participants of Foundation for the National Institute of Health Osteoarthritis Biomarkers Consortium study. Baseline and 24-month MRIs of 600 subjects were assessed. The presence of SHFP oedema (using 0-3 grading scale) and patellar morphology metrics were determined using baseline MRI. Quantitative patellar cartilage volume and semi-quantitative MRI osteoarthritis knee score (MOAKS) variables were extracted. The associations between SHFP oedema and patellar cartilage damage, bone marrow lesion (BML), osteophyte and morphology were evaluated in cross-sectional model. In longitudinal analysis, the associations between oedema and cartilage volume loss (defined using reliable change index) and MOAKS worsening were evaluated. In cross-sectional evaluations, the presence of SHFP oedema was associated with simultaneous lateral patellar cartilage/BML defects and inferior-medial patellar osteophyte size. A significant positive correlation between the degree of patella alta and SHFP oedema was detected (r = 0.259, p < 0.001). The presence of oedema was associated with 24-month cartilage volume loss (odds ratio (OR) 2.11, 95% confidence interval 1.46-3.06) and medial patellar BML size (OR 1.92 (1.15-3.21)) and number (OR 2.50 (1.29-4.88)) worsening. The optimal cut-off value for the grade of baseline SHFP oedema regarding both presence and worsening of patellar structural damage was ≥ 1 (presence of any SHFP hyperintensity). The presence of SHFP oedema could be considered as a predictor of future patellar cartilage loss and BML worsening, and an indicator of simultaneous cartilage, BML and osteophyte defects. • SHFP oedema was associated with simultaneous lateral patellar OA-related structural damage. • SHFP oedema was associated with longitudinal patellar cartilage loss over 24 months. • SHFP oedema could be considered as indicator and predictor

  7. Biological-effective versus conventional dose volume histograms correlated with late genitourinary and gastrointestinal toxicity after external beam radiotherapy for prostate cancer: a matched pair analysis

    Directory of Open Access Journals (Sweden)

    Roeske John C

    2003-05-01

    Full Text Available Abstract Background To determine whether the dose-volume histograms (DVH's for the rectum and bladder constructed using biological-effective dose (BED-DVH's better correlate with late gastrointestinal (GI and genitourinary (GU toxicity after treatment with external beam radiotherapy for prostate cancer than conventional DVH's (C-DVH's. Methods The charts of 190 patients treated with external beam radiotherapy with a minimum follow-up of 2 years were reviewed. Six patients (3.2% were found to have RTOG grade 3 GI toxicity, and similarly 6 patients (3.2% were found to have RTOG grade 3 GU toxicity. Average late C-DVH's and BED-DVH's of the bladder and rectum were computed for these patients as well as for matched-pair control patients. For each matched pair the following measures of normalized difference in the DVH's were computed: (a δAUC = (Area Under Curve [AUC] in grade 3 patient – AUC in grade 0 patient/(AUC in grade 0 patient and (b δV60 = (Percent volume receiving = 60 Gy [V60] in grade 3 patient – V60 in grade 0 patient/(V60 in grade 0 patient. Results As expected, the grade 3 curve is to the right of and above the grade 0 curve for all four sets of average DVH's – suggesting that both the C-DVH and the BED-DVH can be used for predicting late toxicity. δAUC was higher for the BED-DVH's than for the C-DVH's – 0.27 vs 0.23 (p = 0.036 for the rectum and 0.24 vs 0.20 (p = 0.065 for the bladder. δV60 was also higher for the BED-DVH's than for the C-DVH's – 2.73 vs 1.49 for the rectum (p = 0.021 and 1.64 vs 0.71 (p = 0.021 for the bladder. Conclusions When considering well-established dosimetric endpoints used in evaluating treatment plans, BED-DVH's for the rectum and bladder correlate better with late toxicity than C-DVH's and should be considered when attempting to minimize late GI and GU toxicity after external beam radiotherapy for prostate cancer.

  8. Different design of enzyme-triggered CO-releasing molecules (ET-CORMs) reveals quantitative differences in biological activities in terms of toxicity and inflammation

    NARCIS (Netherlands)

    Stamellou, E.; Storz, D.; Botov, S.; Ntasis, E.; Wedel, J.; Sollazzo, S.; Kraemer, B. K.; van Son, W.; Seelen, M.; Schmalz, H. G.; Schmidt, A.; Hafner, M.; Yard, B. A.

    2014-01-01

    Acyloxydiene-Fe(CO)(3) complexes can act as enzyme-triggered CO-releasing molecules (ET-CORMs). Their biological activity strongly depends on the mother compound from which they are derived, i.e, cyclohexenone or cyclohexanedione, and on the position of the ester functionality they harbour. The

  9. Quantitative assessment of irradiated lung volume and lung mass in breast cancer patients treated with tangential fields in combination with deep inspiration breath hold (DIBH)

    International Nuclear Information System (INIS)

    Kapp, Karin Sigrid; Zurl, Brigitte; Stranzl, Heidi; Winkler, Peter

    2010-01-01

    Purpose: Comparison of the amount of irradiated lung tissue volume and mass in patients with breast cancer treated with an optimized tangential-field technique with and without a deep inspiration breath-hold (DIBH) technique and its impact on the normal-tissue complication probability (NTCP). Material and Methods: Computed tomography datasets of 60 patients in normal breathing (NB) and subsequently in DIBH were compared. With a Real-Time Position Management Respiratory Gating System (RPM), anteroposterior movement of the chest wall was monitored and a lower and upper threshold were defined. Ipsilateral lung and a restricted tangential region of the lung were delineated and the mean and maximum doses calculated. Irradiated lung tissue mass was computed based on density values. NTCP for lung was calculated using a modified Lyman-Kutcher-Burman (LKB) model. Results: Mean dose to the ipsilateral lung in DIBH versus NB was significantly reduced by 15%. Mean lung mass calculation in the restricted area receiving ≤ 20 Gy (M 20 ) was reduced by 17% in DIBH but associated with an increase in volume. NTCP showed an improvement in DIBH of 20%. The correlation of individual breathing amplitude with NTCP proved to be independent. Conclusion: The delineation of a restricted area provides the lung mass calculation in patients treated with tangential fields. DIBH reduces ipsilateral lung dose by inflation so that less tissue remains in the irradiated region and its efficiency is supported by a decrease of NTCP. (orig.)

  10. Tracking problems and possible solutions in the quantitative determination of small molecule drugs and metabolites in biological fluids using liquid chromatography-mass spectrometry.

    Science.gov (United States)

    Bakhtiar, Ray; Majumdar, Tapan K

    2007-01-01

    During the last decade, quantification of low molecular weight molecules using liquid chromatography-tandem mass spectrometry in biological fluids has become a common procedure in many preclinical and clinical laboratories. This overview highlights a number of issues involving "small molecule drugs", bioanalytical liquid chromatography-tandem mass spectrometry, which are frequently encountered during assay development. In addition, possible solutions to these issues are proposed with examples in some of the case studies. Topics such as chromatographic peak shape, carry-over, cross-talk, standard curve non-linearity, internal standard selection, matrix effect, and metabolite interference are presented. Since plasma is one of the most widely adopted biological fluid in drug discovery and development, the focus of this discussion will be limited to plasma analysis. This article is not intended to be a comprehensive overview and readers are encouraged to refer to the citations herein.

  11. Simultaneous quantitative profiling of 20 isoprostanoids from omega-3 and omega-6 polyunsaturated fatty acids by LC-MS/MS in various biological samples.

    Science.gov (United States)

    Dupuy, Aude; Le Faouder, Pauline; Vigor, Claire; Oger, Camille; Galano, Jean-Marie; Dray, Cédric; Lee, Jetty Chung-Yung; Valet, Philippe; Gladine, Cécile; Durand, Thierry; Bertrand-Michel, Justine

    2016-05-19

    Isoprostanoids are a group of non-enzymatic oxygenated metabolites of polyunsaturated fatty acids. It belongs to oxylipins group, which are important lipid mediators in biological processes, such as tissue repair, blood clotting, blood vessel permeability, inflammation and immunity regulation. Recently, isoprostanoids from eicosapentaenoic, docosahexaenoic, adrenic and α-linolenic namely F3-isoprostanes, F4-neuroprostanes, F2-dihomo-isoprostanes and F1-phytoprostanes, respectively have attracted attention because of their putative contribution to health. Since isoprostanoids are derived from different substrate of PUFAs and can have similar or opposing biological consequences, a total isoprostanoids profile is essential to understand the overall effect in the testing model. However, the concentration of most isoprostanoids range from picogram to nanogram, therefore a sensitive method to quantify 20 isoprostanoids simultaneously was formulated and measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The lipid portion from various biological samples was extracted prior to LC-MS/MS evaluation. For all the isoprostanoids LOD and LOQ, and the method was validated on plasma samples for matrix effect, yield of extraction and reproducibility were determined. The methodology was further tested for the isoprostanoids profiles in brain and liver of LDLR(-/-) mice with and without docosahexaenoic acid (DHA) supplementation. Our analysis showed similar levels of total F2-isoprostanes and F4-neuroprostanes in the liver and brain of non-supplemented LDLR(-/-) mice. The distribution of different F2-isoprostane isomers varied between tissues but not for F4-neuroprostanes which were predominated by the 4(RS)-4-F4t-neuroprostane isomer. DHA supplementation to LDLR(-/-) mice concomitantly increased total F4-neuroprostanes levels compared to F2-isoprostanes but this effect was more pronounced in the liver than brain. Copyright © 2016 Elsevier B.V. All rights

  12. Quantitative evaluation of the effect of parameters affecting biological and physicochemical phosphate removal from wastewaters in a Multi-Soil-Layering system

    Directory of Open Access Journals (Sweden)

    Khaoula LAMZOURI

    2017-09-01

    Full Text Available Wastewater disposal is a serious problem in Moroccan rural area. Discharged with high levels of phosphorus and nitrogen can result in eutrophication of receiving waters. Biological processes are the most adapted alternative to the needs of these areas, such as the Multi-Soil-Layering (MSL system. The process of rural wastewater treatment by MSL, which is an innovative system used for the first time in Morocco, was studied by modelling the relationships between a set of environmental factors and total phosphorus removed, based upon 153 sampling. Three MSL pilot plants, constructed in three 36 cm × 30 cm × 65 cm plastic boxes, were continuously fed with domestic wastewater, with different hydraulic loading rate (HLR of 250, 500 and 1000 l/m2/day. This study was to investigate and quantify the effect of parameters affecting biological and physico-chemical phosphate removal from wastewaters in this system, using neural networks (NNs and multiple regression analysis (MRA. The results show the influence of the hydraulic loading rate (HLR, Hydrogen potential (pH, phosphorus load (PL, nitrite (NO2--N, Dissolved Oxygen (DO, Biochemical Oxygen Demand (BOD5, and the Nitrate-nitrogen (NO3–-N in the phosphorus removal with a contribution of 36, 16, 15, 12, 9, 7 and 6% respectively.

  13. Dose response models and a quantitative microbial risk assessment framework for the Mycobacterium avium complex that account for recent developments in molecular biology, taxonomy, and epidemiology.

    Science.gov (United States)

    Hamilton, Kerry A; Weir, Mark H; Haas, Charles N

    2017-02-01

    Mycobacterium avium complex (MAC) is a group of environmentally-transmitted pathogens of great public health importance. This group is known to be harbored, amplified, and selected for more human-virulent characteristics by amoeba species in aquatic biofilms. However, a quantitative microbial risk assessment (QMRA) has not been performed due to the lack of dose response models resulting from significant heterogeneity within even a single species or subspecies of MAC, as well as the range of human susceptibilities to mycobacterial disease. The primary human-relevant species and subspecies responsible for the majority of the human disease burden and present in drinking water, biofilms, and soil are M. avium subsp. hominissuis, M. intracellulare, and M. chimaera. A critical review of the published literature identified important health endpoints, exposure routes, and susceptible populations for MAC risk assessment. In addition, data sets for quantitative dose-response functions were extracted from published in vivo animal dosing experiments. As a result, seven new exponential dose response models for human-relevant species of MAC with endpoints of lung lesions, death, disseminated infection, liver infection, and lymph node lesions are proposed. Although current physical and biochemical tests used in clinical settings do not differentiate between M. avium and M. intracellulare, differentiating between environmental species and subspecies of the MAC can aid in the assessment of health risks and control of MAC sources. A framework is proposed for incorporating the proposed dose response models into susceptible population- and exposure route-specific QMRA models. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Reference gene selection for quantitative gene expression studies during biological invasions: A test on multiple genes and tissues in a model ascidian Ciona savignyi.

    Science.gov (United States)

    Huang, Xuena; Gao, Yangchun; Jiang, Bei; Zhou, Zunchun; Zhan, Aibin

    2016-01-15

    As invasive species have successfully colonized a wide range of dramatically different local environments, they offer a good opportunity to study interactions between species and rapidly changing environments. Gene expression represents one of the primary and crucial mechanisms for rapid adaptation to local environments. Here, we aim to select reference genes for quantitative gene expression analysis based on quantitative Real-Time PCR (qRT-PCR) for a model invasive ascidian, Ciona savignyi. We analyzed the stability of ten candidate reference genes in three tissues (siphon, pharynx and intestine) under two key environmental stresses (temperature and salinity) in the marine realm based on three programs (geNorm, NormFinder and delta Ct method). Our results demonstrated only minor difference for stability rankings among the three methods. The use of different single reference gene might influence the data interpretation, while multiple reference genes could minimize possible errors. Therefore, reference gene combinations were recommended for different tissues - the optimal reference gene combination for siphon was RPS15 and RPL17 under temperature stress, and RPL17, UBQ and TubA under salinity treatment; for pharynx, TubB, TubA and RPL17 were the most stable genes under temperature stress, while TubB, TubA and UBQ were the best under salinity stress; for intestine, UBQ, RPS15 and RPL17 were the most reliable reference genes under both treatments. Our results suggest that the necessity of selection and test of reference genes for different tissues under varying environmental stresses. The results obtained here are expected to reveal mechanisms of gene expression-mediated invasion success using C. savignyi as a model species. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Quantitative analysis of receptor imaging

    International Nuclear Information System (INIS)

    Fu Zhanli; Wang Rongfu

    2004-01-01

    Model-based methods for quantitative analysis of receptor imaging, including kinetic, graphical and equilibrium methods, are introduced in detail. Some technical problem facing quantitative analysis of receptor imaging, such as the correction for in vivo metabolism of the tracer and the radioactivity contribution from blood volume within ROI, and the estimation of the nondisplaceable ligand concentration, is also reviewed briefly

  16. Fluorescence properties of the anti-tumour alkaloid luotonin A and new synthetic analogues: pH modulation as an approach to their fluorimetric quantitation in biological samples

    International Nuclear Information System (INIS)

    González-Ruiz, Víctor; González-Cuevas, Yamisley; Arunachalam, Sankaralingam; Martín, M. Antonia; Olives, Ana I.; Ribelles, Pascual; Ramos, M. Teresa; Menéndez, J. Carlos

    2012-01-01

    Luotonin A is an alkaloid structurally related to the natural anti-tumour agent camptothecin. The fluorescence behaviour of luotonin A and a series of six analogues is described in the present work. The influence of solvent polarity and pH on the native fluorescence properties of these alkaloids was studied, finding that in organic solvents or in aqueous solutions (pH 5.5–7.2) the neutral form of the luotonin derivatives emit in the region of 410–450 nm but, in both media, acidification to pH values below 3.0 causes a new emission band to appear at about 500 nm. An ESPT reaction occurs due to the protonation of the basic nitrogen atoms of the pentacyclic ring. Acid-base titrations of luotonin A and its derivatives in aqueous and acetonitrile media were carried out in order to determine their pK a ⁎ values which were around 2, showing these compounds to be very weak bases. In aqueous media, the absence of an iso-emissive point in the emission spectra suggests the existence of more than two species in the proton transfer equilibria. The basicity of the luotonin A derivatives is increased in organic media, and a good correlation between the pK a ⁎ values and the chemical structure was found. The protonation of luotonin A was also studied by 1 H-NMR and 13 C-NMR experiments, which proved the protonation of the nitrogen atoms at the positions 5 and 6 of the pentacyclic ring. The fluorescence quantum yields were determined in ethanol and in aqueous solutions under neutral and acidic conditions. The fluorescence quantum yields were higher in water for the case of the more polar compounds, and the opposite result was obtained for the more hydrophobic ones. The remarkable and interesting fluorescence properties of luotonin A prompted the development of its fluorimetric analytical quantitation, obtaining very good analytical features. - Highlights: ► This is the first study on the fluorescence properties of luotonin A analogues. ► Fluorescence and NMR experiments

  17. Ammonium chloride salting out extraction/cleanup for trace-level quantitative analysis in food and biological matrices by flow injection tandem mass spectrometry.

    Science.gov (United States)

    Nanita, Sergio C; Padivitage, Nilusha L T

    2013-03-20

    A sample extraction and purification procedure that uses ammonium-salt-induced acetonitrile/water phase separation was developed and demonstrated to be compatible with the recently reported method for pesticide residue analysis based on fast extraction and dilution flow injection mass spectrometry (FED-FI-MS). The ammonium salts evaluated were chloride, acetate, formate, carbonate, and sulfate. A mixture of NaCl and MgSO4, salts used in the well-known QuEChERS method, was also tested for comparison. With thermal decomposition/evaporation temperature of salts resulted in negligible ion source residual under typical electrospray conditions, leading to consistent method performance and less instrument cleaning. Although all ammonium salts tested induced acetonitrile/water phase separation, NH4Cl yielded the best performance, thus it was the preferred salting out agent. The NH4Cl salting out method was successfully coupled with FI/MS/MS and tested for fourteen pesticide active ingredients: chlorantraniliprole, cyantraniliprole, chlorimuron ethyl, oxamyl, methomyl, sulfometuron methyl, chlorsulfuron, triflusulfuron methyl, azimsulfuron, flupyrsulfuron methyl, aminocyclopyrachlor, aminocyclopyrachlor methyl, diuron and hexazinone. A validation study was conducted with nine complex matrices: sorghum, rice, grapefruit, canola, milk, eggs, beef, urine and blood plasma. The method is applicable to all analytes, except aminocyclopyrachlor. The method was deemed appropriate for quantitative analysis in 114 out of 126 analyte/matrix cases tested (applicability rate=0.90). The NH4Cl salting out extraction/cleanup allowed expansion of FI/MS/MS for analysis in food of plant and animal origin, and body fluids with increased ruggedness and sensitivity, while maintaining high-throughput (run time=30s/sample). Limits of quantitation (LOQs) of 0.01mgkg(-1) (ppm), the 'well-accepted standard' in pesticide residue analysis, were achieved in >80% of cases tested; while limits of detection

  18. Fluorescence properties of the anti-tumour alkaloid luotonin A and new synthetic analogues: pH modulation as an approach to their fluorimetric quantitation in biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Ruiz, Victor; Gonzalez-Cuevas, Yamisley; Arunachalam, Sankaralingam [S. D. Quimica Analitica, Facultad de Farmacia, Universidad Complutense de Madrid, 28040-Madrid (Spain); Martin, M. Antonia, E-mail: mantonia@farm.ucm.es [S. D. Quimica Analitica, Facultad de Farmacia, Universidad Complutense de Madrid, 28040-Madrid (Spain); Olives, Ana I. [S. D. Quimica Analitica, Facultad de Farmacia, Universidad Complutense de Madrid, 28040-Madrid (Spain); Ribelles, Pascual; Ramos, M. Teresa; Menendez, J. Carlos [D. Quimica Organica y Farmaceutica, Facultad de Farmacia, Universidad Complutense de Madrid, 28040-Madrid (Spain)

    2012-09-15

    Luotonin A is an alkaloid structurally related to the natural anti-tumour agent camptothecin. The fluorescence behaviour of luotonin A and a series of six analogues is described in the present work. The influence of solvent polarity and pH on the native fluorescence properties of these alkaloids was studied, finding that in organic solvents or in aqueous solutions (pH 5.5-7.2) the neutral form of the luotonin derivatives emit in the region of 410-450 nm but, in both media, acidification to pH values below 3.0 causes a new emission band to appear at about 500 nm. An ESPT reaction occurs due to the protonation of the basic nitrogen atoms of the pentacyclic ring. Acid-base titrations of luotonin A and its derivatives in aqueous and acetonitrile media were carried out in order to determine their pK{sub a}{sup Low-Asterisk} values which were around 2, showing these compounds to be very weak bases. In aqueous media, the absence of an iso-emissive point in the emission spectra suggests the existence of more than two species in the proton transfer equilibria. The basicity of the luotonin A derivatives is increased in organic media, and a good correlation between the pK{sub a}{sup Low-Asterisk} values and the chemical structure was found. The protonation of luotonin A was also studied by {sup 1}H-NMR and {sup 13}C-NMR experiments, which proved the protonation of the nitrogen atoms at the positions 5 and 6 of the pentacyclic ring. The fluorescence quantum yields were determined in ethanol and in aqueous solutions under neutral and acidic conditions. The fluorescence quantum yields were higher in water for the case of the more polar compounds, and the opposite result was obtained for the more hydrophobic ones. The remarkable and interesting fluorescence properties of luotonin A prompted the development of its fluorimetric analytical quantitation, obtaining very good analytical features. - Highlights: Black-Right-Pointing-Pointer This is the first study on the fluorescence

  19. Incorporating an Interactive Statistics Workshop into an Introductory Biology Course-Based Undergraduate Research Experience (CURE) Enhances Students' Statistical Reasoning and Quantitative Literacy Skills.

    Science.gov (United States)

    Olimpo, Jeffrey T; Pevey, Ryan S; McCabe, Thomas M

    2018-01-01

    Course-based undergraduate research experiences (CUREs) provide an avenue for student participation in authentic scientific opportunities. Within the context of such coursework, students are often expected to collect, analyze, and evaluate data obtained from their own investigations. Yet, limited research has been conducted that examines mechanisms for supporting students in these endeavors. In this article, we discuss the development and evaluation of an interactive statistics workshop that was expressly designed to provide students with an open platform for graduate teaching assistant (GTA)-mentored data processing, statistical testing, and synthesis of their own research findings. Mixed methods analyses of pre/post-intervention survey data indicated a statistically significant increase in students' reasoning and quantitative literacy abilities in the domain, as well as enhancement of student self-reported confidence in and knowledge of the application of various statistical metrics to real-world contexts. Collectively, these data reify an important role for scaffolded instruction in statistics in preparing emergent scientists to be data-savvy researchers in a globally expansive STEM workforce.

  20. Incorporating an Interactive Statistics Workshop into an Introductory Biology Course-Based Undergraduate Research Experience (CURE) Enhances Students’ Statistical Reasoning and Quantitative Literacy Skills †

    Science.gov (United States)

    Olimpo, Jeffrey T.; Pevey, Ryan S.; McCabe, Thomas M.

    2018-01-01

    Course-based undergraduate research experiences (CUREs) provide an avenue for student participation in authentic scientific opportunities. Within the context of such coursework, students are often expected to collect, analyze, and evaluate data obtained from their own investigations. Yet, limited research has been conducted that examines mechanisms for supporting students in these endeavors. In this article, we discuss the development and evaluation of an interactive statistics workshop that was expressly designed to provide students with an open platform for graduate teaching assistant (GTA)-mentored data processing, statistical testing, and synthesis of their own research findings. Mixed methods analyses of pre/post-intervention survey data indicated a statistically significant increase in students’ reasoning and quantitative literacy abilities in the domain, as well as enhancement of student self-reported confidence in and knowledge of the application of various statistical metrics to real-world contexts. Collectively, these data reify an important role for scaffolded instruction in statistics in preparing emergent scientists to be data-savvy researchers in a globally expansive STEM workforce. PMID:29904549

  1. A comprehensive review of the published assays for the quantitation of the immunosuppressant drug mycophenolic acid and its glucuronidated metabolites in biological fluids.

    Science.gov (United States)

    Syed, Muzeeb; Srinivas, Nuggehally R

    2016-05-01

    Therapeutic use of mycophenolic acid (MPA) is steadily on the rise in combination with other immunosuppressant drugs in transplantation patients. The biotransformation of MPA resulted in the formation of glucuronide metabolites, MPAG and AcMPAG. There are a plethora of assays validated for the analysis of MPA alone or with MPAG/AcMPAG in various biological specimens including plasma/serum, urine, ultrafiltrate, saliva, PBMC, dried blood spots, tissue extract, tumor biopsies and vitreous humor. Based on the need for experimental work, a proper choice of the assay and internal standard may be made using the choices in the literature. While the chemical methods involving high-performance liquid chromatography (HPLC) or LC coupled with triple quadrupole mass spectrometry (LC-MS/MS) are popular, enzymatic assays, in spite of their higher bias, have been used for the routine drug monitoring of MPA. The objectives of the present review are: (a) to provide a focused systematic compilation of the HPLC or LC-MS/MS methods for MPA, MPAG and/or AcMPAG published in the last decade (2005 to current) to enable visual comparison of the methods; (b) to compare and contrast a few enzymatic assays with those of the chemical methods; and (c) to discuss relevant issues/limitations and perspectives on select assays under various subheadings. Copyright © 2016 John Wiley & Sons, Ltd.

  2. The quantitative description of radiation-unduced cell inactivation. 9. Some remarks on the relative biological effect of ionizing radiation upon reproductive death of diploid and polyploid cells

    International Nuclear Information System (INIS)

    Barsukov, V.S.; Malinovskij, O.V.

    1978-01-01

    A model of repproductive death of cells is suggested and tested on the basis of data on relative biological efficiency (RBE) with provision for microdosimetry approaches. The model considers irradiation of cells with charged particles under conditions of linear energy transfers (LET) to the cell nucleus by a particle. This energy is subject to great fluctuations, and irradiation of a cell should be characterized not by the absorbed dose but rather by its stochastic analogue - specific energy. It appears then that RBE should be determined from the specific energy-response relationshjp rather than from dose-response relationship. The followjng main results were obtained: experimental relationship between the yield of sublesions, one-track and two-track lethals and LET correspond to that expected from the literature data; under the conditions considered, RBE can be determined from absorbed dose-pesponse dependency; RBE for sublesions, one- and two-track lethals taken separatly does not depend on the radiation dose and the relationshjp between the resulting RBE and the response is governed by redistribution of contributions of one- and two-track lethals at different doses. The plausibility of the model suggested is thus confirmed

  3. Quantitative determination of biological activity of botulinum toxins utilizing compound muscle action potentials (CMAP), and comparison of neuromuscular transmission blockage and muscle flaccidity among toxins.

    Science.gov (United States)

    Torii, Yasushi; Goto, Yoshitaka; Takahashi, Motohide; Ishida, Setsuji; Harakawa, Tetsuhiro; Sakamoto, Takashi; Kaji, Ryuji; Kozaki, Shunji; Ginnaga, Akihiro

    2010-01-01

    The biological activity of various types of botulinum toxin has been evaluated using the mouse intraperitoneal LD(50) test (ip LD(50)). This method requires a large number of mice to precisely determine toxin activity, and so has posed a problem with regard to animal welfare. We have used a direct measure of neuromuscular transmission, the compound muscle action potential (CMAP), to evaluate the effect of different types of botulinum neurotoxin (NTX), and we compared the effects of these toxins to evaluate muscle relaxation by employing the digit abduction scoring (DAS) assay. This method can be used to measure a broad range of toxin activities the day after administration. Types A, C, C/D, and E NTX reduced the CMAP amplitude one day after administration at below 1 ip LD(50), an effect that cannot be detected using the mouse ip LD(50) assay. The method is useful not only for measuring toxin activity, but also for evaluating the characteristics of different types of NTX. The rat CMAP test is straightforward, highly reproducible, and can directly determine the efficacy of toxin preparations through their inhibition of neuromuscular transmission. Thus, this method may be suitable for pharmacology studies and the quality control of toxin preparations. Copyright 2009 Elsevier Ltd. All rights reserved.

  4. High sensitivity and selectivity in quantitative analysis of drugs in biological samples using 4-column multidimensional micro-UHPLC-MS enabling enhanced sample loading capacity.

    Science.gov (United States)

    de Vries, Ronald; Vereyken, Liesbeth; François, Isabelle; Dillen, Lieve; Vreeken, Rob J; Cuyckens, Filip

    2017-10-09

    Sensitivity is often a critical parameter in quantitative bioanalyses in drug development. For liquid-chromatography-based methods, sensitivity can be improved by reducing the column diameter, but practical sensitivity gains are limited by the reduced sample loading capacity on small internal diameter (I.D.) columns. We developed a set-up that has overcome these limitations in sample loading capacity. The set-up uses 4 columns with gradually decreasing column diameters along the flow-path (2.1 → 1 → 0.5 → 0.15 mm). Samples are pre-concentrated on-line on a 2.1 mm I.D. trapping column and back flushed to a 1 mm I.D. UHPLC analytical column and separated. The peak(s) of interest are transferred using heartcutting to a second trapping column (0.5 mm I.D.), which is back-flushed to a 0.15 mm I.D. micro-UHPLC analytical column for orthogonal separation. The proof of concept of the set-up was demonstrated by the simultaneous analysis of midazolam and 1'-hydroxy midazolam in plasma by injection of 80 μL of protein precipitated plasma. The 4-column funnel set-up proved to be robust and resulted in a 10-50 times better sensitivity compared to a trap-elute approach and 250-500 fold better compared to direct micro-UHPLC analysis. A lower limit of quantification of 100 fg/mL in plasma was obtained for both probe compounds. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Quantitative complete tooth variation among east Asians and Native Americans: developmental biology as a tool for the assessment of human divergence.

    Science.gov (United States)

    Shields, E D

    1996-01-01

    The quantification of total tooth structure derived from X-rays of Vietnamese, Southern Chinese, Mongolians, Western Eskimos, and Peruvian pre-Inca (Huari Empire) populations was used to examine dental divergence and the morphogenetics of change. Multivariate derived distances between the samples helped identify a quasicontinuous web of ethnic groups with two binary clusters ensconced within the web. One cluster was composed of Mongolians, Western Eskimos, and pre-Inca, and the other group consisted of the Southern Chinese and Vietnamese. Mongolians entered the quasicontinuum from a divergent angle (externally influenced) from that of the Southeast Asians. The Chinese and pre-Inca formed the polar samples of the distance superstructure. The pre-Inca sample was the most isolated, its closest neighbor being the Western Eskimos. Univariate and multivariate analyses suggested that the pre-Inca, whose ancestors arrived in America perhaps approximately 30,000 years ago, was the least derived sample. Clearly, microevolutionary change occurred among the samples, but the dental phenotype was resistant to environmental developmental perturbations. An assessment of dental divergence and developmental biology suggested that the overall dental phenotype is a complex multigenic morphological character, and that the observed variation evolved through total genomic drift. The quantified dental phenotype is greater than its highly multigenic algorithm and its development homeostasis is tightly controlled, or canalized, by the deterministic organization of a complex nonlinear epigenetic milieu. The overall dental phenotype quantified here was selectively neutral and a good character to help reconstruct the sequence of human evolution, but if the outlying homeostatic threshold was or will be exceeded in antecedents and descendants, respectively, evolutionary saltation occurs.

  6. A solid-phase microextraction GC/MS/MS method for rapid quantitative analysis of food and beverages for the presence of legally restricted biologically active flavorings.

    Science.gov (United States)

    Bousova, Katerina; Mittendorf, Klaus; Senyuva, Hamide

    2011-01-01

    A method was developed using automated headspace solid-phase microextraction coupled with GC/MS/MS to simultaneously determine the presence of seven biologically active flavoring substances whose levels of use in processed foods is controlled by statutory limits. The method can be applied to identify and quantify the presence of 1,2-benzopyrone (coumarin), beta-asarone, 1-allyl-4-methoxybenzene (estragole), menthofuran, 4-allyl-1 ,2-dimethoxybenzene (methyl eugenol), pulegone, and thujone at levels ranging from 0.5 to 3000 mg/kg. The method has been optimized and validated for three different generic food types categorized on the basis of composition and anticipated use levels of flavorings and food ingredients. The food categories are alcoholic and nonalcoholic beverages; semisolid processed foods (e.g., soups, sauces, confectionary, etc.); and solid foods (muesli, bakery products, etc.). The method is simple, inexpensive, and rapid, and eliminates the use of flammable and toxic solvents. There is no sample preparation, and using MSIMS, unequivocal confirmation of identification is achieved even in highly complex matrixes containing many potential interfering volatiles. The method precision for spiked samples ranged from 2 to 21%, with the greatest variability associated with solid matrixes. The LOD and LOQ values were well below 0.1 and 0.5 mg/kg, respectively, in all cases for individual substances, fulfilling requirements for enforcement purposes. The robustness of the method was demonstrated in a small survey of retail samples of four spirits, five flavored milks, three energy drinks, five liqueurs, five soups, 10 sauces, five herbal teas, and three breakfast cereals.

  7. Connecting qualitative observation and quantitative measurement for enhancing quantitative literacy in plant anatomy course

    Science.gov (United States)

    Nuraeni, E.; Rahmat, A.

    2018-05-01

    Forming of cognitive schemes of plant anatomy concepts is performed by processing of qualitative and quantitative data obtained from microscopic observations. To enhancing student’s quantitative literacy, strategy of plant anatomy course was modified by adding the task to analyze quantitative data produced by quantitative measurement of plant anatomy guided by material course. Participant in this study was 24 biology students and 35 biology education students. Quantitative Literacy test, complex thinking in plant anatomy test and questioner used to evaluate the course. Quantitative literacy capability data was collected by quantitative literacy test with the rubric from the Association of American Colleges and Universities, Complex thinking in plant anatomy by test according to Marzano and questioner. Quantitative literacy data are categorized according to modified Rhodes and Finley categories. The results showed that quantitative literacy of biology education students is better than biology students.

  8. Quantitative cardiac computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Thelen, M.; Dueber, C.; Wolff, P.; Erbel, R.; Hoffmann, T.

    1985-06-01

    The scope and limitations of quantitative cardiac CT have been evaluated in a series of experimental and clinical studies. The left ventricular muscle mass was estimated by computed tomography in 19 dogs (using volumetric methods, measurements in two axes and planes and reference volume). There was good correlation with anatomical findings. The enddiastolic volume of the left ventricle was estimated in 22 patients with cardiomyopathies; using angiography as a reference, CT led to systematic under-estimation. It is also shown that ECG-triggered magnetic resonance tomography results in improved visualisation and may be expected to improve measurements of cardiac morphology.

  9. NODC Standard Product: International ocean atlas Volume 2 - Biological atlas of the Arctic Seas 2000 - Plankton of the Barents and Kara Seas (1 disc set) (NODC Accession 0098568)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Presented in this CD-ROM are physical and biological data for the region extending from the Barents Sea to the Kara Sea during 158 scientific cruises for the period...

  10. Monitoring viable cells of the biological control agent Lactobacillus plantarum PM411 in aerial plant surfaces by means of a strain-specific viability quantitative PCR.

    Science.gov (United States)

    Daranas, Núria; Bonaterra, Anna; Francés, Jesús; Cabrefiga, Jordi; Montesinos, Emilio; Badosa, Esther

    2018-03-09

    v-qPCR could also be developed for monitoring other strains on plant surfaces not only biological control agents but also beneficial bacteria useful in the sustainable management of crop production. Copyright © 2018 American Society for Microbiology.

  11. Quantitative assessment of global and regional air trappings using non-rigid registration and regional specific volume change of inspiratory/expiratory CT scans: Studies on healthy volunteers and asthmatics

    International Nuclear Information System (INIS)

    Lee, Eun Sol; Seo, Joon Beom; Lee, Hyun Joo; Chae, Eun Jin; Lee, Sang Min; Oh, Sang Young; Kim, Nam Kug

    2015-01-01

    The purpose of this study was to compare air trapping in healthy volunteers with asthmatics using pulmonary function test and quantitative data, such as specific volume change from paired inspiratory CT and registered expiratory CT. Sixteen healthy volunteers and 9 asthmatics underwent paired inspiratory/expiratory CT. DeltaSV, which represents the ratio of air fraction released after exhalation, was measured with paired inspiratory and anatomically registered expiratory CT scans. Air trapping indexes, DeltaSV0.4 and DeltaSV0.5, were defined as volume fraction of lung below 0.4 and 0.5 DeltaSV, respectively. To assess the gravity effect of air-trapping, DeltaSV values of anterior and posterior lung at three different levels were measured and DeltaSV ratio of anterior lung to posterior lung was calculated. Color-coded DeltaSV map of the whole lung was generated and visually assessed. Mean DeltaSV, DeltaSV0.4, and DeltaSV0.5 were compared between healthy volunteers and asthmatics. In asthmatics, correlation between air trapping indexes and clinical parameters were assessed. Mean DeltaSV, DeltaSV0.4, and DeltaSV0.5 in asthmatics were significantly higher than those in healthy volunteer group (all p < 0.05). DeltaSV values in posterior lung in asthmatics were significantly higher than those in healthy volunteer group (p = 0.049). In asthmatics, air trapping indexes, such as DeltaSV0.5 and DeltaSV0.4, showed negative strong correlation with FEF25-75, FEV1, and FEV1/FVC. DeltaSV map of asthmatics showed abnormal geographic pattern in 5 patients (55.6%) and disappearance of anterior-posterior gradient in 3 patients (33.3%). Quantitative assessment of DeltaSV (the ratio of air fraction released after exhalation) shows the difference in extent of air trapping between health volunteers and asthmatics.

  12. Quantitative assessment of global and regional air trappings using non-rigid registration and regional specific volume change of inspiratory/expiratory CT scans: Studies on healthy volunteers and asthmatics

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun Sol; Seo, Joon Beom; Lee, Hyun Joo; Chae, Eun Jin; Lee, Sang Min; Oh, Sang Young; Kim, Nam Kug [Dept. of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of)

    2015-06-15

    The purpose of this study was to compare air trapping in healthy volunteers with asthmatics using pulmonary function test and quantitative data, such as specific volume change from paired inspiratory CT and registered expiratory CT. Sixteen healthy volunteers and 9 asthmatics underwent paired inspiratory/expiratory CT. DeltaSV, which represents the ratio of air fraction released after exhalation, was measured with paired inspiratory and anatomically registered expiratory CT scans. Air trapping indexes, DeltaSV0.4 and DeltaSV0.5, were defined as volume fraction of lung below 0.4 and 0.5 DeltaSV, respectively. To assess the gravity effect of air-trapping, DeltaSV values of anterior and posterior lung at three different levels were measured and DeltaSV ratio of anterior lung to posterior lung was calculated. Color-coded DeltaSV map of the whole lung was generated and visually assessed. Mean DeltaSV, DeltaSV0.4, and DeltaSV0.5 were compared between healthy volunteers and asthmatics. In asthmatics, correlation between air trapping indexes and clinical parameters were assessed. Mean DeltaSV, DeltaSV0.4, and DeltaSV0.5 in asthmatics were significantly higher than those in healthy volunteer group (all p < 0.05). DeltaSV values in posterior lung in asthmatics were significantly higher than those in healthy volunteer group (p = 0.049). In asthmatics, air trapping indexes, such as DeltaSV0.5 and DeltaSV0.4, showed negative strong correlation with FEF25-75, FEV1, and FEV1/FVC. DeltaSV map of asthmatics showed abnormal geographic pattern in 5 patients (55.6%) and disappearance of anterior-posterior gradient in 3 patients (33.3%). Quantitative assessment of DeltaSV (the ratio of air fraction released after exhalation) shows the difference in extent of air trapping between health volunteers and asthmatics.

  13. Quantitative secondary electron detection

    Science.gov (United States)

    Agrawal, Jyoti; Joy, David C.; Nayak, Subuhadarshi

    2018-05-08

    Quantitative Secondary Electron Detection (QSED) using the array of solid state devices (SSD) based electron-counters enable critical dimension metrology measurements in materials such as semiconductors, nanomaterials, and biological samples (FIG. 3). Methods and devices effect a quantitative detection of secondary electrons with the array of solid state detectors comprising a number of solid state detectors. An array senses the number of secondary electrons with a plurality of solid state detectors, counting the number of secondary electrons with a time to digital converter circuit in counter mode.

  14. [Methods of quantitative proteomics].

    Science.gov (United States)

    Kopylov, A T; Zgoda, V G

    2007-01-01

    In modern science proteomic analysis is inseparable from other fields of systemic biology. Possessing huge resources quantitative proteomics operates colossal information on molecular mechanisms of life. Advances in proteomics help researchers to solve complex problems of cell signaling, posttranslational modification, structure and functional homology of proteins, molecular diagnostics etc. More than 40 various methods have been developed in proteomics for quantitative analysis of proteins. Although each method is unique and has certain advantages and disadvantages all these use various isotope labels (tags). In this review we will consider the most popular and effective methods employing both chemical modifications of proteins and also metabolic and enzymatic methods of isotope labeling.

  15. Electromagnetic fields in biological systems

    National Research Council Canada - National Science Library

    Lin, James C

    2012-01-01

    "Focusing on exposure, induced fields, and absorbed energy, this volume covers the interaction of electromagnetic fields and waves with biological systems, spanning static fields to terahertz waves...

  16. AICE Survey of USSR Air Pollution Literature, Volume 15: A Third Compilation of Technical Reports on the Biological Effects and the Public Health Aspects of Atmospheric Pollutants.

    Science.gov (United States)

    Nuttonson, M. Y.

    Ten papers were translated: Maximum permissible concentrations of noxious substances in the atmospheric air of populated areas; Some aspects of the biological effect of microconcentrations of two chloroisocyanates; The toxicology of low concentrations of aromatic hydrocarbons; Chronic action of low concentrations of acrolein in air on the…

  17. Exploring Phytoplankton Population Investigation Growth to Enhance Quantitative Literacy

    Science.gov (United States)

    Baumgartner, Erin; Biga, Lindsay; Bledsoe, Karen; Dawson, James; Grammer, Julie; Howard, Ava; Snyder, Jeffrey

    2015-01-01

    Quantitative literacy is essential to biological literacy (and is one of the core concepts in "Vision and Change in Undergraduate Biology Education: A Call to Action"; AAAS 2009). Building quantitative literacy is a challenging endeavor for biology instructors. Integrating mathematical skills into biological investigations can help build…

  18. Quantitative mass imaging of single biological macromolecules.

    Science.gov (United States)

    Young, Gavin; Hundt, Nikolas; Cole, Daniel; Fineberg, Adam; Andrecka, Joanna; Tyler, Andrew; Olerinyova, Anna; Ansari, Ayla; Marklund, Erik G; Collier, Miranda P; Chandler, Shane A; Tkachenko, Olga; Allen, Joel; Crispin, Max; Billington, Neil; Takagi, Yasuharu; Sellers, James R; Eichmann, Cédric; Selenko, Philipp; Frey, Lukas; Riek, Roland; Galpin, Martin R; Struwe, Weston B; Benesch, Justin L P; Kukura, Philipp

    2018-04-27

    The cellular processes underpinning life are orchestrated by proteins and their interactions. The associated structural and dynamic heterogeneity, despite being key to function, poses a fundamental challenge to existing analytical and structural methodologies. We used interferometric scattering microscopy to quantify the mass of single biomolecules in solution with 2% sequence mass accuracy, up to 19-kilodalton resolution, and 1-kilodalton precision. We resolved oligomeric distributions at high dynamic range, detected small-molecule binding, and mass-imaged proteins with associated lipids and sugars. These capabilities enabled us to characterize the molecular dynamics of processes as diverse as glycoprotein cross-linking, amyloidogenic protein aggregation, and actin polymerization. Interferometric scattering mass spectrometry allows spatiotemporally resolved measurement of a broad range of biomolecular interactions, one molecule at a time. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  19. Advances in radiation biology

    International Nuclear Information System (INIS)

    Lett, J.T.; Ehmann, U.K.; Cox, A.B.

    1987-01-01

    The classical period of radiation biology is coming to a close. Such change always occurs at a time when the ideas and concepts that promoted the burgeoning of an infant science are no longer adequate. This volume covers a number of areas in which new ideas and research are playing a vital role, including cellular radiation sensitivity, radioactive waste disposal, and space radiation biology

  20. Quantitative proteomic analysis of HIV-1 infected CD4+ T cells reveals an early host response in important biological pathways: Protein synthesis, cell proliferation, and T-cell activation

    Energy Technology Data Exchange (ETDEWEB)

    Navare, Arti T.; Sova, Pavel; Purdy, David E.; Weiss, Jeffrey M. [Department of Microbiology, University of Washington, Seattle, WA (United States); Wolf-Yadlin, Alejandro [Department of Genome Sciences, University of Washington, Seattle, WA (United States); Korth, Marcus J.; Chang, Stewart T.; Proll, Sean C. [Department of Microbiology, University of Washington, Seattle, WA (United States); Jahan, Tahmina A. [Proteomics Resource, UW Medicine at South Lake Union, Seattle, WA (United States); Krasnoselsky, Alexei L.; Palermo, Robert E. [Department of Microbiology, University of Washington, Seattle, WA (United States); Katze, Michael G., E-mail: honey@uw.edu [Department of Microbiology, University of Washington, Seattle, WA (United States); Washington National Primate Research Center, University of Washington, Seattle, WA (United States)

    2012-07-20

    Human immunodeficiency virus (HIV-1) depends upon host-encoded proteins to facilitate its replication while at the same time inhibiting critical components of innate and/or intrinsic immune response pathways. To characterize the host cell response on protein levels in CD4+ lymphoblastoid SUP-T1 cells after infection with HIV-1 strain LAI, we used mass spectrometry (MS)-based global quantitation with iTRAQ (isobaric tag for relative and absolute quantification). We found 266, 60 and 22 proteins differentially expressed (DE) (P-value{<=}0.05) at 4, 8, and 20 hours post-infection (hpi), respectively, compared to time-matched mock-infected samples. The majority of changes in protein abundance occurred at an early stage of infection well before the de novo production of viral proteins. Functional analyses of these DE proteins showed enrichment in several biological pathways including protein synthesis, cell proliferation, and T-cell activation. Importantly, these early changes before the time of robust viral production have not been described before.

  1. West Hackberry Strategic Petroleum Reserve site brine disposal monitoring, Year I report. Volume V. Supporting data for estuarine hydrology, discharge plume analysis, chemical oceanography, biological oceanography, and data management. Final report

    Energy Technology Data Exchange (ETDEWEB)

    DeRouen, L.R.; Hann, R.W.; Casserly, D.M.; Giammona, C.; Lascara, V.J. (eds.)

    1983-02-01

    This project centers around the Strategic Petroleum Site (SPR) known as the West Hackberry salt dome which located in southwestern Louisiana, and which is designed to store 241 million barrels of crude oil. Oil storage caverns are formed by injecting water into salt deposits, and pumping out the resulting brine. Studies described in this report were designed as follow-on studies to three months of pre-discharge characterization work, and include data collected during the first year of brine leaching operations. The objectives were to: (1) characterize the environment in terms of physical, chemical and biological attributes; (2) determine if significant adverse changes in ecosystem productivity and stability of the biological community are occurring as a result of brine discharge; and (3) determine the magnitude of any change observed. Volume V contains appendices for the following: supporting data for estuarine hydrology and hydrography; supporting data analysis of discharge plume; supporting data for water and sediment chemistry; CTD/DO and pH profiles during biological monitoring; supporting data for nekton; and supporting data for data management.

  2. Volume-based quantitative FDG PET/CT metrics and their association with optimal debulking and progression-free survival in patients with recurrent ovarian cancer undergoing secondary cytoreductive surgery

    Energy Technology Data Exchange (ETDEWEB)

    Vargas, H.A.; Burger, I.A.; Micco, M.; Sosa, R.E.; Weber, W.; Hricak, H.; Sala, E. [Memorial Sloan Kettering Cancer Center, Department of Radiology, New York, NY (United States); Goldman, D.A. [Memorial Sloan Kettering Cancer Center, Department of Epidemiology and Biostatistics, New York, NY (United States); Chi, D.S. [Memorial Sloan Kettering Cancer Center, Department of Surgery, New York, NY (United States)

    2015-11-15

    Our aim was to evaluate the associations between quantitative {sup 18}F-fluorodeoxyglucose positron-emission tomography (FDG-PET) uptake metrics, optimal debulking (OD) and progression-free survival (PFS) in patients with recurrent ovarian cancer undergoing secondary cytoreductive surgery. Fifty-five patients with recurrent ovarian cancer underwent FDG-PET/CT within 90 days prior to surgery. Standardized uptake values (SUV{sub max}), metabolically active tumour volumes (MTV), and total lesion glycolysis (TLG) were measured on PET. Exact logistic regression, Kaplan-Meier curves and the log-rank test were used to assess associations between imaging metrics, OD and PFS. MTV (p = 0.0025) and TLG (p = 0.0043) were associated with OD; however, there was no significant association between SUV{sub max} and debulking status (p = 0.83). Patients with an MTV above 7.52 mL and/or a TLG above 35.94 g had significantly shorter PFS (p = 0.0191 for MTV and p = 0.0069 for TLG). SUV{sub max} was not significantly related to PFS (p = 0.10). PFS estimates at 3.5 years after surgery were 0.42 for patients with an MTV ≤ 7.52 mL and 0.19 for patients with an MTV > 7.52 mL; 0.46 for patients with a TLG ≤ 35.94 g and 0.15 for patients with a TLG > 35.94 g. FDG-PET metrics that reflect metabolic tumour burden are associated with optimal secondary cytoreductive surgery and progression-free survival in patients with recurrent ovarian cancer. (orig.)

  3. Volume-based quantitative FDG PET/CT metrics and their association with optimal debulking and progression-free survival in patients with recurrent ovarian cancer undergoing secondary cytoreductive surgery

    International Nuclear Information System (INIS)

    Vargas, H.A.; Burger, I.A.; Micco, M.; Sosa, R.E.; Weber, W.; Hricak, H.; Sala, E.; Goldman, D.A.; Chi, D.S.

    2015-01-01

    Our aim was to evaluate the associations between quantitative 18 F-fluorodeoxyglucose positron-emission tomography (FDG-PET) uptake metrics, optimal debulking (OD) and progression-free survival (PFS) in patients with recurrent ovarian cancer undergoing secondary cytoreductive surgery. Fifty-five patients with recurrent ovarian cancer underwent FDG-PET/CT within 90 days prior to surgery. Standardized uptake values (SUV max ), metabolically active tumour volumes (MTV), and total lesion glycolysis (TLG) were measured on PET. Exact logistic regression, Kaplan-Meier curves and the log-rank test were used to assess associations between imaging metrics, OD and PFS. MTV (p = 0.0025) and TLG (p = 0.0043) were associated with OD; however, there was no significant association between SUV max and debulking status (p = 0.83). Patients with an MTV above 7.52 mL and/or a TLG above 35.94 g had significantly shorter PFS (p = 0.0191 for MTV and p = 0.0069 for TLG). SUV max was not significantly related to PFS (p = 0.10). PFS estimates at 3.5 years after surgery were 0.42 for patients with an MTV ≤ 7.52 mL and 0.19 for patients with an MTV > 7.52 mL; 0.46 for patients with a TLG ≤ 35.94 g and 0.15 for patients with a TLG > 35.94 g. FDG-PET metrics that reflect metabolic tumour burden are associated with optimal secondary cytoreductive surgery and progression-free survival in patients with recurrent ovarian cancer. (orig.)

  4. Quantitative research.

    Science.gov (United States)

    Watson, Roger

    2015-04-01

    This article describes the basic tenets of quantitative research. The concepts of dependent and independent variables are addressed and the concept of measurement and its associated issues, such as error, reliability and validity, are explored. Experiments and surveys – the principal research designs in quantitative research – are described and key features explained. The importance of the double-blind randomised controlled trial is emphasised, alongside the importance of longitudinal surveys, as opposed to cross-sectional surveys. Essential features of data storage are covered, with an emphasis on safe, anonymous storage. Finally, the article explores the analysis of quantitative data, considering what may be analysed and the main uses of statistics in analysis.

  5. Quantitative habitability.

    Science.gov (United States)

    Shock, Everett L; Holland, Melanie E

    2007-12-01

    A framework is proposed for a quantitative approach to studying habitability. Considerations of environmental supply and organismal demand of energy lead to the conclusions that power units are most appropriate and that the units for habitability become watts per organism. Extreme and plush environments are revealed to be on a habitability continuum, and extreme environments can be quantified as those where power supply only barely exceeds demand. Strategies for laboratory and field experiments are outlined that would quantify power supplies, power demands, and habitability. An example involving a comparison of various metabolisms pursued by halophiles is shown to be well on the way to a quantitative habitability analysis.

  6. Applications of tissue heterogeneity corrections and biologically effective dose volume histograms in assessing the doses for accelerated partial breast irradiation using an electronic brachytherapy source

    Science.gov (United States)

    Shi, Chengyu; Guo, Bingqi; Cheng, Chih-Yao; Eng, Tony; Papanikolaou, Nikos

    2010-09-01

    A low-energy electronic brachytherapy source (EBS), the model S700 Axxent™ x-ray device developed by Xoft Inc., has been used in high dose rate (HDR) intracavitary accelerated partial breast irradiation (APBI) as an alternative to an Ir-192 source. The prescription dose and delivery schema of the electronic brachytherapy APBI plan are the same as the Ir-192 plan. However, due to its lower mean energy than the Ir-192 source, an EBS plan has dosimetric and biological features different from an Ir-192 source plan. Current brachytherapy treatment planning methods may have large errors in treatment outcome prediction for an EBS plan. Two main factors contribute to the errors: the dosimetric influence of tissue heterogeneities and the enhancement of relative biological effectiveness (RBE) of electronic brachytherapy. This study quantified the effects of these two factors and revisited the plan quality of electronic brachytherapy APBI. The influence of tissue heterogeneities is studied by a Monte Carlo method and heterogeneous 'virtual patient' phantoms created from CT images and structure contours; the effect of RBE enhancement in the treatment outcome was estimated by biologically effective dose (BED) distribution. Ten electronic brachytherapy APBI cases were studied. The results showed that, for electronic brachytherapy cases, tissue heterogeneities and patient boundary effect decreased dose to the target and skin but increased dose to the bones. On average, the target dose coverage PTV V100 reduced from 95.0% in water phantoms (planned) to only 66.7% in virtual patient phantoms (actual). The actual maximum dose to the ribs is 3.3 times higher than the planned dose; the actual mean dose to the ipsilateral breast and maximum dose to the skin were reduced by 22% and 17%, respectively. Combining the effect of tissue heterogeneities and RBE enhancement, BED coverage of the target was 89.9% in virtual patient phantoms with RBE enhancement (actual BED) as compared to 95

  7. Applications of tissue heterogeneity corrections and biologically effective dose volume histograms in assessing the doses for accelerated partial breast irradiation using an electronic brachytherapy source

    Energy Technology Data Exchange (ETDEWEB)

    Shi Chengyu; Guo Bingqi; Eng, Tony; Papanikolaou, Nikos [Cancer Therapy and Research Center, University of Texas Health Science Center at San Antonio, TX 78229 (United States); Cheng, Chih-Yao, E-mail: shic@uthscsa.ed [Radiation Oncology Department, Oklahoma University Health Science Center, Oklahoma, OK 73104 (United States)

    2010-09-21

    A low-energy electronic brachytherapy source (EBS), the model S700 Axxent(TM) x-ray device developed by Xoft Inc., has been used in high dose rate (HDR) intracavitary accelerated partial breast irradiation (APBI) as an alternative to an Ir-192 source. The prescription dose and delivery schema of the electronic brachytherapy APBI plan are the same as the Ir-192 plan. However, due to its lower mean energy than the Ir-192 source, an EBS plan has dosimetric and biological features different from an Ir-192 source plan. Current brachytherapy treatment planning methods may have large errors in treatment outcome prediction for an EBS plan. Two main factors contribute to the errors: the dosimetric influence of tissue heterogeneities and the enhancement of relative biological effectiveness (RBE) of electronic brachytherapy. This study quantified the effects of these two factors and revisited the plan quality of electronic brachytherapy APBI. The influence of tissue heterogeneities is studied by a Monte Carlo method and heterogeneous 'virtual patient' phantoms created from CT images and structure contours; the effect of RBE enhancement in the treatment outcome was estimated by biologically effective dose (BED) distribution. Ten electronic brachytherapy APBI cases were studied. The results showed that, for electronic brachytherapy cases, tissue heterogeneities and patient boundary effect decreased dose to the target and skin but increased dose to the bones. On average, the target dose coverage PTV V{sub 100} reduced from 95.0% in water phantoms (planned) to only 66.7% in virtual patient phantoms (actual). The actual maximum dose to the ribs is 3.3 times higher than the planned dose; the actual mean dose to the ipsilateral breast and maximum dose to the skin were reduced by 22% and 17%, respectively. Combining the effect of tissue heterogeneities and RBE enhancement, BED coverage of the target was 89.9% in virtual patient phantoms with RBE enhancement (actual BED) as

  8. Applications of tissue heterogeneity corrections and biologically effective dose volume histograms in assessing the doses for accelerated partial breast irradiation using an electronic brachytherapy source

    International Nuclear Information System (INIS)

    Shi Chengyu; Guo Bingqi; Eng, Tony; Papanikolaou, Nikos; Cheng, Chih-Yao

    2010-01-01

    A low-energy electronic brachytherapy source (EBS), the model S700 Axxent(TM) x-ray device developed by Xoft Inc., has been used in high dose rate (HDR) intracavitary accelerated partial breast irradiation (APBI) as an alternative to an Ir-192 source. The prescription dose and delivery schema of the electronic brachytherapy APBI plan are the same as the Ir-192 plan. However, due to its lower mean energy than the Ir-192 source, an EBS plan has dosimetric and biological features different from an Ir-192 source plan. Current brachytherapy treatment planning methods may have large errors in treatment outcome prediction for an EBS plan. Two main factors contribute to the errors: the dosimetric influence of tissue heterogeneities and the enhancement of relative biological effectiveness (RBE) of electronic brachytherapy. This study quantified the effects of these two factors and revisited the plan quality of electronic brachytherapy APBI. The influence of tissue heterogeneities is studied by a Monte Carlo method and heterogeneous 'virtual patient' phantoms created from CT images and structure contours; the effect of RBE enhancement in the treatment outcome was estimated by biologically effective dose (BED) distribution. Ten electronic brachytherapy APBI cases were studied. The results showed that, for electronic brachytherapy cases, tissue heterogeneities and patient boundary effect decreased dose to the target and skin but increased dose to the bones. On average, the target dose coverage PTV V 100 reduced from 95.0% in water phantoms (planned) to only 66.7% in virtual patient phantoms (actual). The actual maximum dose to the ribs is 3.3 times higher than the planned dose; the actual mean dose to the ipsilateral breast and maximum dose to the skin were reduced by 22% and 17%, respectively. Combining the effect of tissue heterogeneities and RBE enhancement, BED coverage of the target was 89.9% in virtual patient phantoms with RBE enhancement (actual BED) as compared to 95

  9. XVIII Mendeleev congress on general and applied chemistry. Summaries of reports in five volumes. Volume 5. IV Russian-French symposium Supramolecular systems in chemistry and biology. II Russian-Indian symposium on organic chemistry. International symposium on present-day radiochemistry Radiochemistry: progress and prospects. International symposium Green chemistry, stable evolution and social responsibility of chemists. Symposium Nucleophilic hydrogen substitution in aromatic systems and related reactions

    International Nuclear Information System (INIS)

    2007-01-01

    The 5 volume of the XVIII Mendeleev congress on general and applied chemistry includes summaries of reports on the subjects of sypramolecular systems in chemistry and biology, organic chemistry, modern radiochemistry, green chemistry - development and social responsibility of chemists, nucleophilic hydrogen substitution in aromatic systems and related chemical reactions [ru

  10. Proceedings of the 27th annual conference on engineering in medicine and biology. Volume 16. Conference held at Philadelphia, Pennsylvania, October 6--10, 1974

    International Nuclear Information System (INIS)

    Anon.

    1974-01-01

    Fifty-four sessions were held on various aspects of engineering in medicine and biology. Approximately ten papers were presented in each session and summaries of the papers are included. A paper on nuclear fueled circulatory support systems describes 238 Pu fueled blood cooled heat exchangers and implants using 241 Am, 9 Be, and 90 Sr in dogs. One dog died as a result of an extensive pulmonary neoplasm. Two sessions were devoted to cardiac pacemakers; topics included were data management systems, safety factors, implantation status of the NU-5 nuclear pacemaker, a rechargeable cardiac pacemaker system, and longevity of implantable pulse generators. A session on corporeal imaging included papers on computer processing of chest x-ray pictures, fluoroscopic image enhancement using a storage vidicon, ACTA (automatic computerized transverse axial tomographic)--the whole body scanner, and reconstruction of the image from the ACTA whole body x-ray scanner. (U.S.)

  11. Applied quantitative finance

    CERN Document Server

    Chen, Cathy; Overbeck, Ludger

    2017-01-01

    This volume provides practical solutions and introduces recent theoretical developments in risk management, pricing of credit derivatives, quantification of volatility and copula modeling. This third edition is devoted to modern risk analysis based on quantitative methods and textual analytics to meet the current challenges in banking and finance. It includes 14 new contributions and presents a comprehensive, state-of-the-art treatment of cutting-edge methods and topics, such as collateralized debt obligations, the high-frequency analysis of market liquidity, and realized volatility. The book is divided into three parts: Part 1 revisits important market risk issues, while Part 2 introduces novel concepts in credit risk and its management along with updated quantitative methods. The third part discusses the dynamics of risk management and includes risk analysis of energy markets and for cryptocurrencies. Digital assets, such as blockchain-based currencies, have become popular b ut are theoretically challenging...

  12. Quantitative Finance

    Science.gov (United States)

    James, Jessica

    2017-01-01

    Quantitative finance is a field that has risen to prominence over the last few decades. It encompasses the complex models and calculations that value financial contracts, particularly those which reference events in the future, and apply probabilities to these events. While adding greatly to the flexibility of the market available to corporations and investors, it has also been blamed for worsening the impact of financial crises. But what exactly does quantitative finance encompass, and where did these ideas and models originate? We show that the mathematics behind finance and behind games of chance have tracked each other closely over the centuries and that many well-known physicists and mathematicians have contributed to the field.

  13. Frontiers in mathematical biology

    CERN Document Server

    1994-01-01

    Volume 100, which is the final volume of the LNBM series serves to commemorate the acievements in two decades of this influential collection of books in mathematical biology. The contributions, by the leading mathematical biologists, survey the state of the art in the subject, and offer speculative, philosophical and critical analyses of the key issues confronting the field. The papers address fundamental issues in cell and molecular biology, organismal biology, evolutionary biology, population ecology, community and ecosystem ecology, and applied biology, plus the explicit and implicit mathematical challenges. Cross-cuttting issues involve the problem of variation among units in nonlinear systems, and the related problems of the interactions among phenomena across scales of space, time and organizational complexity.

  14. Effects of buffer ionization in protein transition volumes.

    Science.gov (United States)

    Lee, Soyoung; Heerklotz, Heiko; Chalikian, Tigran V

    2010-05-01

    Protein denaturation events are generally associated with a change in the state of ionization of abnormally titrating groups and, therefore, are coupled with changes in buffer ionization/neutralization equilibria. Consequently, buffer ionization should influence the measured change in volume accompanying protein denaturation. Changes in volume accompanying protein denaturation reflect the differential packing and hydration of polypeptide chains in their native and denatured conformations while also describing the pressure stability of proteins. A characteristic feature of conformational transitions of globular proteins is a near zero change in volume that is comparable in magnitude with the volume of ionization of biologically relevant buffers. Thus, the impact of buffer ionization on the volume of protein denaturation could be very significant with the potential to affect not only its magnitude but also its sign. To investigate this point quantitatively, we performed pressure perturbation calorimetric (PPC) studies of lysozyme and ribonuclease A at pH 3.0 in four buffers differing in their ionization volumes. Our results identify buffer ionization as an important determinant of protein transition volume that needs to be carefully taken into account. We emphasize that the importance of our results is not limited to PPC measurements but is more general and applies to all volumetric investigations, in particular, extending to the derivation of the pressure-temperature phase diagram of protein stability.

  15. A Quantitative Gas Chromatographic Ethanol Determination.

    Science.gov (United States)

    Leary, James J.

    1983-01-01

    Describes a gas chromatographic experiment for the quantitative determination of volume percent ethanol in water ethanol solutions. Background information, procedures, and typical results are included. Accuracy and precision of results are both on the order of two percent. (JN)

  16. Branching processes in biology

    CERN Document Server

    Kimmel, Marek

    2015-01-01

    This book provides a theoretical background of branching processes and discusses their biological applications. Branching processes are a well-developed and powerful set of tools in the field of applied probability. The range of applications considered includes molecular biology, cellular biology, human evolution and medicine. The branching processes discussed include Galton-Watson, Markov, Bellman-Harris, Multitype, and General Processes. As an aid to understanding specific examples, two introductory chapters, and two glossaries are included that provide background material in mathematics and in biology. The book will be of interest to scientists who work in quantitative modeling of biological systems, particularly probabilists, mathematical biologists, biostatisticians, cell biologists, molecular biologists, and bioinformaticians. The authors are a mathematician and cell biologist who have collaborated for more than a decade in the field of branching processes in biology for this new edition. This second ex...

  17. Quantitative radiography

    International Nuclear Information System (INIS)

    Brase, J.M.; Martz, H.E.; Waltjen, K.E.; Hurd, R.L.; Wieting, M.G.

    1986-01-01

    Radiographic techniques have been used in nondestructive evaluation primarily to develop qualitative information (i.e., defect detection). This project applies and extends the techniques developed in medical x-ray imaging, particularly computed tomography (CT), to develop quantitative information (both spatial dimensions and material quantities) on the three-dimensional (3D) structure of solids. Accomplishments in FY 86 include (1) improvements in experimental equipment - an improved microfocus system that will give 20-μm resolution and has potential for increased imaging speed, and (2) development of a simple new technique for displaying 3D images so as to clearly show the structure of the object. Image reconstruction and data analysis for a series of synchrotron CT experiments conducted by LLNL's Chemistry Department has begun

  18. Quantitative lymphography

    International Nuclear Information System (INIS)

    Mostbeck, A.; Lofferer, O.; Kahn, P.; Partsch, H.; Koehn, H.; Bialonczyk, Ch.; Koenig, B.

    1984-01-01

    Labelled colloids and macromolecules are removed lymphatically. The uptake of tracer in the regional lymphnodes is a parameter of lymphatic flow. Due to great variations in patient shape - obesity, cachexia - and accompanying variations in counting efficiencies quantitative measurements with reasonable accuracy have not been reported to date. A new approach to regional absorption correction is based on the combination of transmission and emission scans for each patient. The transmission scan is used for calculation of an absorption correction matrix. Accurate superposition of the correction matrix and the emission scan is achieved by computing the centers of gravity of point sources and - in the case of aligning opposite views - by cross correlation of binary images. In phantom studies the recovery was high (98.3%) and the coefficient of variation of repeated measurement below 1%. In patient studies a standardized stress is a prerequisite for reliable and comparable results. Discrimination between normals (14.3 +- 4.2D%) and patients with lymphedema (2.05 +- 2.5D%) was highly significant using praefascial lymphography and sc injection. Clearence curve analysis of the activities at the injection site, however, gave no reliable data for this purpose. In normals, the uptake in lymphnodes after im injection is by one order of magnitude lower then the uptake after sc injection. The discrimination between normals and patients with postthromboic syndrome was significant. Lymphography after ic injection was in the normal range in 2/3 of the patients with lymphedema and is therefore of no diagnostic value. The difference in uptake after ic and sc injection demonstrated for the first time by our quantitative method provides new insights into the pathophysiology of lymphedema and needs further investigation. (Author)

  19. Quantitative 3D imaging of yeast by hard X-ray tomography.

    Science.gov (United States)

    Zheng, Ting; Li, Wenjie; Guan, Yong; Song, Xiangxia; Xiong, Ying; Liu, Gang; Tian, Yangchao

    2012-05-01

    Full-field hard X-ray tomography could be used to obtain three-dimensional (3D) nanoscale structures of biological samples. The image of the fission yeast, Schizosaccharomyces pombe, was clearly visualized based on Zernike phase contrast imaging technique and heavy metal staining method at a spatial resolution better than 50 nm at the energy of 8 keV. The distributions and shapes of the organelles during the cell cycle were clearly visualized and two types of organelle were distinguished. The results for cells during various phases were compared and the ratios of organelle volume to cell volume can be analyzed quantitatively. It showed that the ratios remained constant between growth and division phase and increased strongly in stationary phase, following the shape and size of two types of organelles changes. Our results demonstrated that hard X-ray microscopy was a complementary method for imaging and revealing structural information for biological samples. Copyright © 2011 Wiley Periodicals, Inc.

  20. Programme Biology - Health protection

    International Nuclear Information System (INIS)

    1975-01-01

    The scientific results for 1975, of the five-year Biology-Health Protection programme adopted in 1971, are presented in two volumes. In volume one, Research in Radiation Protection are developed exclusively, including the following topics: measurement and interpretation of radiation (dosimetry); transfer of radioactive nuclides in the constituents of the environment; hereditary effects of radiation; short-term effects (acute irradiation syndrome and its treatment); long-term effects and toxicology of radioactive elements. In volume, two Research on applications in Agriculture and Medicine are developed. It includes: mutagenesis; soil-plant relations; radiation analysis; food conservation; cell culture; radioentomology. Research on applications in Medicine include: Nuclear Medicine and Neutron Dosimetry

  1. Quantitative Thermochronology

    Science.gov (United States)

    Braun, Jean; van der Beek, Peter; Batt, Geoffrey

    2006-05-01

    Thermochronology, the study of the thermal history of rocks, enables us to quantify the nature and timing of tectonic processes. Quantitative Thermochronology is a robust review of isotopic ages, and presents a range of numerical modeling techniques to allow the physical implications of isotopic age data to be explored. The authors provide analytical, semi-analytical, and numerical solutions to the heat transfer equation in a range of tectonic settings and under varying boundary conditions. They then illustrate their modeling approach built around a large number of case studies. The benefits of different thermochronological techniques are also described. Computer programs on an accompanying website at www.cambridge.org/9780521830577 are introduced through the text and provide a means of solving the heat transport equation in the deforming Earth to predict the ages of rocks and compare them directly to geological and geochronological data. Several short tutorials, with hints and solutions, are also included. Numerous case studies help geologists to interpret age data and relate it to Earth processes Essential background material to aid understanding and using thermochronological data Provides a thorough treatise on numerical modeling of heat transport in the Earth's crust Supported by a website hosting relevant computer programs and colour slides of figures from the book for use in teaching

  2. Analyzing the Biology on the System Level

    OpenAIRE

    Tong, Wei

    2016-01-01

    Although various genome projects have provided us enormous static sequence information, understanding of the sophisticated biology continues to require integrating the computational modeling, system analysis, technology development for experiments, and quantitative experiments all together to analyze the biology architecture on various levels, which is just the origin of systems biology subject. This review discusses the object, its characteristics, and research attentions in systems biology,...

  3. Nuclear physics and biology

    International Nuclear Information System (INIS)

    Valentin, L.

    1994-01-01

    This paper is about nuclear instrumentation and biological concepts, based on images from appropriate Β detectors. First, three detectors are described: the SOFI detector, for gene mapping, the SOFAS detector, for DNA sequencing and the RIHR detector, for in situ hybridization. Then, the paper presents quantitative imaging in molecular genetic and functional imaging. (TEC)

  4. Quantitative Ultrasound Measurements at the Heel

    DEFF Research Database (Denmark)

    Daugschies, M.; Brixen, K.; Hermann, P.

    2015-01-01

    Calcaneal quantitative ultrasound can be used to predict osteoporotic fracture risk, but its ability to monitor therapy is unclear possibly because of its limited precision. We developed a quantitative ultrasound device (foot ultrasound scanner) that measures the speed of sound at the heel...... with the foot ultrasound scanner reduced precision errors by half (p quantitative ultrasound measurements is feasible. (E-mail: m.daugschies@rad.uni-kiel.de) (C) 2015 World Federation for Ultrasound in Medicine & Biology....

  5. High resolution gas volume change sensor

    International Nuclear Information System (INIS)

    Dirckx, Joris J. J.; Aernouts, Jef E. F.; Aerts, Johan R. M.

    2007-01-01

    Changes of gas quantity in a system can be measured either by measuring pressure changes or by measuring volume changes. As sensitive pressure sensors are readily available, pressure change is the commonly used technique. In many physiologic systems, however, buildup of pressure influences the gas exchange mechanisms, thus changing the gas quantity change rate. If one wants to study the gas flow in or out of a biological gas pocket, measurements need to be done at constant pressure. In this article we present a highly sensitive sensor for quantitative measurements of gas volume change at constant pressure. The sensor is based on optical detection of the movement of a droplet of fluid enclosed in a capillary. The device is easy to use and delivers gas volume data at a rate of more than 15 measurements/s and a resolution better than 0.06 μl. At the onset of a gas quantity change the sensor shows a small pressure artifact of less than 15 Pa, and at constant change rates the pressure artifact is smaller than 10 Pa or 0.01% of ambient pressure

  6. The quantitative Morse theorem

    OpenAIRE

    Loi, Ta Le; Phien, Phan

    2013-01-01

    In this paper, we give a proof of the quantitative Morse theorem stated by {Y. Yomdin} in \\cite{Y1}. The proof is based on the quantitative Sard theorem, the quantitative inverse function theorem and the quantitative Morse lemma.

  7. A note on stereological estimation of the volume-weighted second moment of particle volume

    DEFF Research Database (Denmark)

    Jensen, E B; Sørensen, Flemming Brandt

    1991-01-01

    It is shown that for a variety of biological particle shapes, the volume-weighted second moment of particle volume can be estimated stereologically using only the areas of particle transects, which can be estimated manually by point-counting....

  8. Automatic quantitative metallography

    International Nuclear Information System (INIS)

    Barcelos, E.J.B.V.; Ambrozio Filho, F.; Cunha, R.C.

    1976-01-01

    The quantitative determination of metallographic parameters is analysed through the description of Micro-Videomat automatic image analysis system and volumetric percentage of perlite in nodular cast irons, porosity and average grain size in high-density sintered pellets of UO 2 , and grain size of ferritic steel. Techniques adopted are described and results obtained are compared with the corresponding ones by the direct counting process: counting of systematic points (grid) to measure volume and intersections method, by utilizing a circunference of known radius for the average grain size. The adopted technique for nodular cast iron resulted from the small difference of optical reflectivity of graphite and perlite. Porosity evaluation of sintered UO 2 pellets is also analyzed [pt

  9. 2006 In Vitro Biology Meeting. Volume 42

    Science.gov (United States)

    2006-04-25

    Toothbrushes Vitor Hugo Fernandes, Funda9co Educacional Montes Claros, and D. L. C6sar E-2005 Proteomics Analysis of Osteosarcoma Cells Michael McCord...coiiceiris, *tm ut fth sitfsus inid va Ininimuelp iuaiscctiin rince plains that pttslUnC h itgh aiuinuti it uninc especially in Europe. To that end. sse...stimulation, and culture environment. Of the many ecotoxicology nowadays especially the environmental scientists. This uses of cul:ured T cells, those

  10. Biological Agents

    Science.gov (United States)

    ... E-Tools Safety and Health Topics / Biological Agents Biological Agents This page requires that javascript be enabled ... 202) 693-2300 if additional assistance is required. Biological Agents Menu Overview In Focus: Ebola Frederick A. ...

  11. Quantitative nature of overexpression experiments

    Science.gov (United States)

    Moriya, Hisao

    2015-01-01

    Overexpression experiments are sometimes considered as qualitative experiments designed to identify novel proteins and study their function. However, in order to draw conclusions regarding protein overexpression through association analyses using large-scale biological data sets, we need to recognize the quantitative nature of overexpression experiments. Here I discuss the quantitative features of two different types of overexpression experiment: absolute and relative. I also introduce the four primary mechanisms involved in growth defects caused by protein overexpression: resource overload, stoichiometric imbalance, promiscuous interactions, and pathway modulation associated with the degree of overexpression. PMID:26543202

  12. Redox environment in stem and differentiated cells: A quantitative approach

    Directory of Open Access Journals (Sweden)

    O.G. Lyublinskaya

    2017-08-01

    Full Text Available Stem cells are believed to maintain a specific intracellular redox status through a combination of enhanced removal capacity and limited production of ROS. In the present study, we challenge this assumption by developing a quantitative approach for the analysis of the pro- and antioxidant ability of human embryonic stem cells in comparison with their differentiated descendants, as well as adult stem and non-stem cells. Our measurements showed that embryonic stem cells are characterized by low ROS level, low rate of extracellular hydrogen peroxide removal and low threshold for peroxide-induced cytotoxicity. However, biochemical normalization of these parameters to cell volume/protein leads to matching of normalized values in stem and differentiated cells and shows that tested in the present study cells (human embryonic stem cells and their fibroblast-like progenies, adult mesenchymal stem cells, lymphocytes, HeLa maintain similar intracellular redox status. Based on these observations, we propose to use ROS concentration averaged over the cell volume instead of ROS level as a measure of intracellular redox balance. We show that attempts to use ROS level for comparative analysis of redox status of morphologically different cells could lead to false conclusions. Methods for the assessment of ROS concentration based on flow cytometry analysis with the use of H2DCFDA dye and HyPer, genetically encoded probe for hydrogen peroxide, are discussed. Keywords: Embryonic stem cells, Differentiated cells, ROS, Redox status, H2DCFDA, HyPer, Flow cytometry, Quantitative redox biology

  13. Tomography studies of biological cells on polymer scaffolds

    International Nuclear Information System (INIS)

    Thurner, P; Mueller, B; Sennhauser, U; Hubbell, J; Mueller, R

    2004-01-01

    Advances in cell biology and tissue engineering rely heavily on performing 2D cell culture experiments. Analysis of these is conventionally done with 2D imaging techniques such as light (LM) or electron microscopy (SEM), since they are readily available. Cells, however, might act significantly differently when cultured in 2D or 3D environments. In order to analyse cells in a 3D arrangement, new imaging techniques are necessary not only in order to visualize the periphery of the cell culture in reflection mode but also to perform qualitative and quantitative investigations of the inner parts. Synchrotron radiation micro-computed tomography (SRμCT) using hard x-rays was shown to be a promising tool that can be used for 3D cell culture visualization. SRμCT allows not only visualization of cell cultures in their native 3D environment but also use of the volumetric nature of this imaging procedure to evaluate the cells quantitatively. In our approach, cells were seeded on polymer yarns, stained and measured with SRμCT in absorption and in differential absorption contrast mode. A new segmentation procedure was developed and the measured volumetric data were quantitatively assessed. Quantification parameters included total cell volume, total yarn volume, cell volume density, which is the ratio of cell to yarn volume, and the radial cell mass distribution. The applied variation of the staining parameter of gold enhancement incubation time was shown to have significant influence on the cell volume density. Differential absorption contrast mode was found to provide similar but no additional information on the investigated sample. Using novel approaches of hierarchical volumetric imaging allows closure of the gap between imaging of whole organs and single cells and might be expanded to even higher resolutions, offering investigation of the cell machinery in closer detail

  14. Common variants at 6q22 and 17q21 are associated with intracranial volume

    NARCIS (Netherlands)

    Arfan Ikram, M.; Fornage, M.; Smith, A.V.; Seshadri, S.; Schmidt, R.; Debette, S.; Vrooman, H.A.; Sigurdsson, S.; Ropele, S.; Taal, H.R.; Mook-Kanamori, D.O.; Coker, L.H.; Longstreth, Jr. W.T.; Niessen, W.J.; DeStefano, A.L.; Beiser, A.; Zijdenbos, A.P.; Struchalin, M.; Jack, C.R.; Rivadeneira, F.; Uitterlinden, A.G.; Knopman, D.S.; Hartikainen, A.-L.; Pennell, C.E.; Thiering, E.; Steegers, E.A.P.; Hakonarson, H.; Heinrich, J.; Palmer, L.J.; Jarvelin, M.-R.; McCarthy, M.I.; Grant, S.F.A.; St Pourcain, B.; Timpson, N.J.; Smith, G.D.; Sovio, U.; van Beijsterveldt, C.E.M.; Groen-Blokhuis, M.M.; Hottenga, J.J.; Middeldorp, C.M.; Nivard, M.G.; Willemsen, G.; Boomsma, D.I.; Nalls, M.A.; Au, R.; Hofman, A.; Gudnason, H.; van der Lugt, A.; Harris, T.B.; Meeks, W.M.; Vernooij, M.W.; van Buchem, M.A.; Catellier, D.; Jaddoe, V.W.V.; Gudnason, V.; Windham, B.G.; Wolf, P.A.; van Duijn, C.M.; Mosley, T.H.; Schmidt, H.; Launer, L.J.; Breteler, M.M.B.; DeCarli, C.S.

    2012-01-01

    During aging, intracranial volume remains unchanged and represents maximally attained brain size, while various interacting biological phenomena lead to brain volume loss. Consequently, intracranial volume and brain volume in late life reflect different genetic influences. Our genome-wide

  15. Common variants at 6q22 and 17q21 are associated with intracranial volume

    NARCIS (Netherlands)

    M.A. Ikram (Arfan); M. Fornage (Myriam); G.D. Smith; S. Seshadri (Sudha); R. Schmidt (Reinhold); S. Debette (Stéphanie); H.A. Vrooman (Henri); S. Sigurdsson (Stefan); S. Ropele (Stefan); H.R. Taal (Rob); D.O. Mook-Kanamori (Dennis); L.H. Coker (Laura); W.T. Longstreth Jr; W.J. Niessen (Wiro); A.L. DeStefano (Anita); A. Beiser (Alexa); A.P. Zijdenbos; M.V. Struchalin (Maksim); C.R. Jack Jr. (Clifford); F. Rivadeneira Ramirez (Fernando); A.G. Uitterlinden (André); D.S. Knopman (David); A.L. Hartikainen; C.E. Pennell (Craig); E. Thiering (Eelisabeth); E.A.P. Steegers (Eric); H. Hakonarson (Hakon); J. Heinrich (Joachim); C. Palmer (Cameron); M.-R. Jarvelin (Marjo-Riitta); M.I. McCarthy (Mark); S.F.A. Grant (Struan); B.S. Pourcain (Beate); N.J. Timpson (Nicholas); G.D. Smith; U. Sovio (Ulla); M.A. Nalls (Michael); R. Au (Rhoda); A. Hofman (Albert); H. Gudnason (Haukur); A. van der Lugt (Aad); T.B. Harris (Tamara); W.M. Meeks (William); M.W. Vernooij (Meike); M.A. van Buchem (Mark); D.J. Catellier (Diane); V.W.V. Jaddoe (Vincent); V. Gudnason (Vilmundur); B.G. Windham (B Gwen); P.A. Wolf (Philip); C.M. van Duijn (Cornelia); T.H. Mosley (Thomas); R. Schmidt (Reinhold); L.J. Launer (Lenore); M.M.B. Breteler (Monique); C. DeCarli (Charles); L.S. Adair (Linda); W.Q. Ang (Wei); M. Atalay (Mustafa); C.E.M. van Beijsterveldt (Toos); N.E. Bergen (Nienke); P.J. Benke (Paul); D. Berry (Diane); L. Coin (Lachlan); O.S.P. Davis (Oliver S.); P. Elliott (Paul); C. Flexeder (Claudia); T.M. Frayling (Timothy); R. Gaillard (Romy); M. Groen-Blokhuis (Maria); L.-K. Goh; C.M.A. Haworth (Claire M.); D. Hadley (David); J. Hedebrand (Johannes); A. Hinney (Anke); J.N. Hirschhorn (Joel); J.W. Holloway (John); J.J. Holst; J.J. Hottenga (Jouke Jan); M. Horikoshi (Momoko); V. Huikari (Ville); E. Hypponen (Elina); T.O. Kilpeläinen (Tuomas); M. Kirin (Mirna); M. Kowgier (Matthew); T.A. Lakka (Timo); L.A. Lange (Leslie); D.A. Lawlor (Debbie); T. Lehtimäki (Terho); A. Lewin (Alex); C.M. Lindgren (Cecilia); V. Lindi (Virpi); R. Maggi (Reedik); J.A. Marsh (Julie); C.M. Middeldorp (Christel); I.Y. Millwood (Iona); J.C. Murray (Jeffrey); M. Nivard (Michel); C. Nohr (Christian); I. Ntalla (Ioanna); E. Oken (Emily); K. Panoutsopoulou (Kalliope); J. Pararajasingham (Jennifer); A. Rodriguez (Alfredo Chapin); R.M. Salem (Rany); S. Sebert (Sylvain); N. Siitonen (Niina); D.P. Strachan (David); Y.Y. Teo (Yik Ying); B. Valcárcel (Beatriz); G.A.H.M. Willemsen (Gonneke); E. Zeggini (Eleftheria); D.I. Boomsma (Dorret); C. Cooper (Charles); M.H. Gillman (Matthew); B. Hocher (Berthold); T.A. Lakka (Timo); K.L. Mohlke (Karen); G.V. Dedoussis (George); K.K. Ong (Ken); E. Pearson (Ewan); T.S. Price (Thomas); C. Power (Christopher); O. Raitakari (Olli); S-M. Saw (Seang-Mei); A. Scherag (Andre); O. Simell (Olli); T.I.A. Sørensen (Thorkild); J.F. Wilson (James)

    2012-01-01

    textabstractDuring aging, intracranial volume remains unchanged and represents maximally attained brain size, while various interacting biological phenomena lead to brain volume loss. Consequently, intracranial volume and brain volume in late life reflect different genetic influences. Our

  16. Quantitative clinical radiobiology

    International Nuclear Information System (INIS)

    Bentzen, S.M.

    1993-01-01

    Based on a series of recent papers, a status is given of our current ability to quantify the radiobiology of human tumors and normal tissues. Progress has been made in the methods of analysis. This includes the introduction of 'direct' (maximum likelihood) analysis, incorporation of latent-time in the analyses, and statistical approaches to allow for the many factors of importance in predicting tumor-control probability of normal-tissue complications. Quantitative clinical radiobiology of normal tissues is reviewed with emphasis on fractionation sensitivity, repair kinetics, regeneration, latency, and the steepness of dose-response curves. In addition, combined modality treatment, functional endpoints, and the search for a correlation between the occurrence of different endpoints in the same individual are discussed. For tumors, quantitative analyses of fractionation sensitivity, repair kinetics, reoxygenation, and regeneration are reviewed. Other factors influencing local control are: Tumor volume, histopathologic differentiation and hemoglobin concentration. Also, the steepness of the dose-response curve for tumors is discussed. Radiobiological strategies for improving radiotherapy are discussed with emphasis on non-standard fractionation and individualization of treatment schedules. (orig.)

  17. Ernst Mayr and Evolutionary Biology

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 10; Issue 7. Polemics and Synthesis: Ernst Mayr and Evolutionary Biology. Renee M Borges. General Article Volume 10 Issue 7 July 2005 pp 21-33. Fulltext. Click here to view fulltext PDF. Permanent link:

  18. An Integrated Approach to Biology

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 16; Issue 8. An Integrated Approach to Biology. Aniket Bhattacharya. General Article Volume 16 Issue 8 August 2011 pp 742-753. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/016/08/0742-0753 ...

  19. Evolutionary Biology Research in India

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 5; Issue 10. Evolutionary Biology Research in India. Information and Announcements Volume 5 Issue 10 October 2000 pp 102-104. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/005/10/0102-0104 ...

  20. A Physicist Looks at Biology

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 4; Issue 11. A Physicist Looks at Biology. Max Delbrück. Classics Volume 4 Issue 11 November 1999 pp 89-102. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/004/11/0089-0102. Author Affiliations.

  1. How Computers are Arming biology!

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 23; Issue 1. In-vitro to In-silico - How Computers are Arming biology! Geetha Sugumaran Sushila Rajagopal. Face to Face Volume 23 Issue 1 January 2018 pp 83-102. Fulltext. Click here to view fulltext PDF. Permanent link:

  2. Liver volume, intrahepatic fat and body weight in the course of a lifestyle interventional study. Analysis with quantitative MR-based methods; Lebervolumen, Leberfettanteil und Koerpergewicht im Verlauf einer Lebensstilinterventionsstudie. Eine Analyse mit quantitativen MR-basierten Methoden

    Energy Technology Data Exchange (ETDEWEB)

    Bongers, M.N. [Klinikum der Eberhard-Karls-Universitaet Tuebingen, Abteilung fuer Diagnostische und Interventionelle Radiologie, Tuebingen (Germany); Universitaetsklinikum Tuebingen, Sektion fuer Experimentelle Radiologie der Abteilung fuer Diagnostische und Interventionelle Radiologie, Tuebingen (Germany); Stefan, N.; Fritsche, A.; Haering, H.U. [Universitaetsklinikum Tuebingen, Innere Medizin IV - Endokrinologie und Diabetologie, Angiologie, Nephrologie und Klinische Chemie, Tuebingen (Germany); Helmholtz-Zentrum Muenchen an der Universitaet Tuebingen, Institut fuer Diabetes-Forschung und Metabolische Erkrankungen (IDM), Tuebingen (Germany); Nikolaou, K. [Klinikum der Eberhard-Karls-Universitaet Tuebingen, Abteilung fuer Diagnostische und Interventionelle Radiologie, Tuebingen (Germany); Schick, F. [Universitaetsklinikum Tuebingen, Sektion fuer Experimentelle Radiologie der Abteilung fuer Diagnostische und Interventionelle Radiologie, Tuebingen (Germany); Machann, J. [Universitaetsklinikum Tuebingen, Sektion fuer Experimentelle Radiologie der Abteilung fuer Diagnostische und Interventionelle Radiologie, Tuebingen (Germany); Helmholtz-Zentrum Muenchen an der Universitaet Tuebingen, Institut fuer Diabetes-Forschung und Metabolische Erkrankungen (IDM), Tuebingen (Germany); Deutsches Zentrum fuer Diabetesforschung (DZD), Neuherberg (Germany)

    2015-04-01

    The aim of this study was to investigate potential associations between changes in liver volume, the amount of intrahepatic lipids (IHL) and body weight during lifestyle interventions. In a prospective study 150 patients with an increased risk for developing type 2 diabetes mellitus were included who followed a caloric restriction diet for 6 months. In the retrospective analysis 18 women and 9 men (age range 22-71 years) with an average body mass index (BMI) of 32 kg/m{sup 2} were enrolled. The liver volume was determined at the beginning and after 6 months by three-dimensional magnetic resonance imaging (3D-MRI, echo gradient, opposed-phase) and IHLs were quantified by volume-selective MR spectroscopy in single voxel stimulated echo acquisition mode (STEAM). Univariable and multivariable correlation analyses between changes of liver volume (Δliver volume), intrahepatic lipids (ΔIHL) and body weight (ΔBW) were performed. Univariable correlation analysis in the whole study cohort showed associations between ΔIHL and ΔBW (r = 0.69; p < 0.0001), ΔIHL and Δliver volume (r = 0.66; p = 0.0002) as well as ΔBW and Δliver volume (r = 0.5; p = 0.0073). Multivariable correlation analysis revealed that changes of liver volume are primarily determined by changes in IHL independent of changes in body weight (β = 0.0272; 95 % CI: 0.0155-0.034; p < 0.0001). Changes of liver volume during lifestyle interventions are independent of changes of body weight primarily determined by changes of IHL. These results show the reversibility of augmented liver volume in steatosis if it is possible to reduce IHLs during lifestyle interventions. (orig.) [German] Lassen sich Zusammenhaenge zwischen den Aenderungen des Lebervolumens, des Anteils intrahepatischer Lipide und des Koerpergewichts waehrend einer Lebensstilintervention feststellen ?In einer prospektiven Interventionsstudie unterzogen sich 150 Probanden mit erhoehtem Diabetesrisiko fuer 6 Monate einer diaetetischen

  3. [Studies of biologic activation associated with molecular receptor increase and tumor response in ChL6/L6 protocol patients; Studies in phantoms; Quantitative SPECT; Preclinical studies; and Clinical studies]. DOE annual report, 1994-95

    International Nuclear Information System (INIS)

    DeNardo, S.J.

    1995-01-01

    The authors describe results which have not yet been published from their associated studies listed in the title. For the first, they discuss Lym-1 single chain genetically engineered molecules, analysis of molecular genetic coded messages to enhance tumor response, and human dosimetry and therapeutic human use radiopharmaceuticals. Studies in phantoms includes a discussion of planar image quantitation, counts coincidence correction, organ studies, tumor studies, and 90 Y quantitation with Bremsstrahlung imaging. The study on SPECT discusses attenuation correction and scatter correction. Preclinical studies investigated uptake of 90 Y-BrE-3 in mice using autoradiography. Clinical studies discuss image quantitation verses counts from biopsy samples, S factors for radiation dose calculation, 67 Cu imaging studies for lymphoma cancer, and 111 In MoAb imaging studies for breast cancer to predict 90 Y MoAb therapy

  4. Quantitative isotopes miction cystoureterography (QIMCU)

    International Nuclear Information System (INIS)

    Szy, D.A.G.; Stroetges, M.W.; Funke-Voelkers, R.

    1982-01-01

    A simple method for a quantitative evaluation of vesicoureteral reflux was developed. It allows the determination of a) the volume of reflux b) the volume of the bladder at each point of time during the examination. The QIMCU gives an insight into the dynamic of reflux, of reflux volume, and of actual bladder volume. The clinical application in 37 patients with 53 insufficient ureteral orifices (i.e. reflux) showed that the onset of reflux occured in 60% as early as in the first five minutes of the examination but later in the remaining 40%. The maximal reflux was found only in 26% during the first five minutes. The reflux volume exceeded in more than 50% the amount of 3.5 ml. The international grading corresponds with the reflux volume determined by this method. Radionuclide cystoureterography can be used as well in childhood as in adults. Because the radiaction exposure is low, the method can be recommended for the initial examination and for follow up studies. (Author)

  5. Biology as an Integrating Natural Science Domain

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 13; Issue 3. Biology as an Integrating Natural Science Domain: A Proposal for BSc (Hons) in Integrated Biology. Kambadur Muralidhar. Classroom Volume 13 Issue 3 March 2008 pp 272-276 ...

  6. Quantitative reactive modeling and verification.

    Science.gov (United States)

    Henzinger, Thomas A

    Formal verification aims to improve the quality of software by detecting errors before they do harm. At the basis of formal verification is the logical notion of correctness , which purports to capture whether or not a program behaves as desired. We suggest that the boolean partition of software into correct and incorrect programs falls short of the practical need to assess the behavior of software in a more nuanced fashion against multiple criteria. We therefore propose to introduce quantitative fitness measures for programs, specifically for measuring the function, performance, and robustness of reactive programs such as concurrent processes. This article describes the goals of the ERC Advanced Investigator Project QUAREM. The project aims to build and evaluate a theory of quantitative fitness measures for reactive models. Such a theory must strive to obtain quantitative generalizations of the paradigms that have been success stories in qualitative reactive modeling, such as compositionality, property-preserving abstraction and abstraction refinement, model checking, and synthesis. The theory will be evaluated not only in the context of software and hardware engineering, but also in the context of systems biology. In particular, we will use the quantitative reactive models and fitness measures developed in this project for testing hypotheses about the mechanisms behind data from biological experiments.

  7. Calculation of integrated biological response in brachytherapy

    International Nuclear Information System (INIS)

    Dale, Roger G.; Coles, Ian P.; Deehan, Charles; O'Donoghue, Joseph A.

    1997-01-01

    Purpose: To present analytical methods for calculating or estimating the integrated biological response in brachytherapy applications, and which allow for the presence of dose gradients. Methods and Materials: The approach uses linear-quadratic (LQ) formulations to identify an equivalent biologically effective dose (BED eq ) which, if applied to a specified tissue volume, would produce the same biological effect as that achieved by a given brachytherapy application. For simple geometrical cases, BED multiplying factors have been derived which allow the equivalent BED for tumors to be estimated from a single BED value calculated at a dose reference point. For more complex brachytherapy applications a voxel-by-voxel determination of the equivalent BED will be more accurate. Equations are derived which when incorporated into brachytherapy software would facilitate such a process. Results: At both high and low dose rates, the BEDs calculated at the dose reference point are shown to be lower than the true values by an amount which depends primarily on the magnitude of the prescribed dose; the BED multiplying factors are higher for smaller prescribed doses. The multiplying factors are less dependent on the assumed radiobiological parameters. In most clinical applications involving multiple sources, particularly those in multiplanar arrays, the multiplying factors are likely to be smaller than those derived here for single sources. The overall suggestion is that the radiobiological consequences of dose gradients in well-designed brachytherapy treatments, although important, may be less significant than is sometimes supposed. The modeling exercise also demonstrates that the integrated biological effect associated with fractionated high-dose-rate (FHDR) brachytherapy will usually be different from that for an 'equivalent' continuous low-dose-rate (CLDR) regime. For practical FHDR regimes involving relatively small numbers of fractions, the integrated biological effect to

  8. Combinational pixel-by-pixel and object-level classifying, segmenting, and agglomerating in performing quantitative image analysis that distinguishes between healthy non-cancerous and cancerous cell nuclei and delineates nuclear, cytoplasm, and stromal material objects from stained biological tissue materials

    Science.gov (United States)

    Boucheron, Laura E

    2013-07-16

    Quantitative object and spatial arrangement-level analysis of tissue are detailed using expert (pathologist) input to guide the classification process. A two-step method is disclosed for imaging tissue, by classifying one or more biological materials, e.g. nuclei, cytoplasm, and stroma, in the tissue into one or more identified classes on a pixel-by-pixel basis, and segmenting the identified classes to agglomerate one or more sets of identified pixels into segmented regions. Typically, the one or more biological materials comprises nuclear material, cytoplasm material, and stromal material. The method further allows a user to markup the image subsequent to the classification to re-classify said materials. The markup is performed via a graphic user interface to edit designated regions in the image.

  9. Quantitative assessment of the hepatic metabolic volume product in patients with diffuse hepatic steatosis and normal controls through use of FDG-PET and MR imaging: a novel concept.

    Science.gov (United States)

    Bural, Gonca G; Torigian, Drew A; Burke, Anne; Houseni, Mohamed; Alkhawaldeh, Khaled; Cucchiara, Andrew; Basu, Sandip; Alavi, Abass

    2010-06-01

    The aim of this study was to compare hepatic standardized uptake values (SUVs) and hepatic metabolic volumetric products (HMVP) between patients of diffuse hepatic steatosis and control subjects with normal livers. Twenty-seven subjects were included in the study (13 men and 14 women; age range, 34-72 years). All had 18F-2-fluoro-2-D-deoxyglucose-positron emission tomography (FDG-PET) and magnetic resonance imaging (MRI) scans with an interscan interval of 0-5 months. Twelve of 27 subjects had diffuse hepatic steatosis on MRI. The remaining 15 were selected as age-matched controls based on normal liver parenchyma on MRI. Mean and maximum hepatic SUVs were calculated for both patient groups on FDG-PET images. Hepatic volumes were measured from MRI. HMVP in each subject was subsequently calculated by multiplication of hepatic volume by mean hepatic SUV. HMVPs as well as mean and maximum hepatic SUVs were compared between the two study groups. HMVPs, mean hepatic SUVs, and maximum hepatic SUVs were greater (statistically significant, p < 0.05) in subjects with diffuse hepatic steatosis compared to those in the control group. The increase in HMVP is the result of increased hepatic metabolic activity likely related to the diffuse hepatic steatosis. The active inflammatory process related to the diffuse hepatic steatosis is the probable explanation for the increase in hepatic metabolic activity on FDG-PET study.

  10. Quantitative tomographic measurements of opaque multiphase flows

    Energy Technology Data Exchange (ETDEWEB)

    GEORGE,DARIN L.; TORCZYNSKI,JOHN R.; SHOLLENBERGER,KIM ANN; O' HERN,TIMOTHY J.; CECCIO,STEVEN L.

    2000-03-01

    An electrical-impedance tomography (EIT) system has been developed for quantitative measurements of radial phase distribution profiles in two-phase and three-phase vertical column flows. The EIT system is described along with the computer algorithm used for reconstructing phase volume fraction profiles. EIT measurements were validated by comparison with a gamma-densitometry tomography (GDT) system. The EIT system was used to accurately measure average solid volume fractions up to 0.05 in solid-liquid flows, and radial gas volume fraction profiles in gas-liquid flows with gas volume fractions up to 0.15. In both flows, average phase volume fractions and radial volume fraction profiles from GDT and EIT were in good agreement. A minor modification to the formula used to relate conductivity data to phase volume fractions was found to improve agreement between the methods. GDT and EIT were then applied together to simultaneously measure the solid, liquid, and gas radial distributions within several vertical three-phase flows. For average solid volume fractions up to 0.30, the gas distribution for each gas flow rate was approximately independent of the amount of solids in the column. Measurements made with this EIT system demonstrate that EIT may be used successfully for noninvasive, quantitative measurements of dispersed multiphase flows.

  11. Modern Biology

    OpenAIRE

    ALEKSIC, Branko

    2014-01-01

    The purpose of this course is to learn the philosophy, principles, and techniques of modern biology. The course is particularly designed for those who have not learned biology previously or whose major is other than biology, and who may think that they do not need to know any biology at all. The topics are covered in a rather general, overview manner, but certain level of diligence in grasping concepts and memorizing the terminology is expected.

  12. Quantitation of regional cerebral blood flow corrected for partial volume effect using O-15 water and PET: II. Normal values and gray matter blood flow response to visual activation

    DEFF Research Database (Denmark)

    Law, I; Iida, H; Holm, S

    2000-01-01

    One of the most limiting factors for the accurate quantification of physiologic parameters with positron emission tomography (PET) is the partial volume effect (PVE). To assess the magnitude of this contribution to the measurement of regional cerebral blood flow (rCBF), the authors have formulated...... or 3D). Furthermore, the authors wanted to measure the activation response in the occipital gray matter compartment, and in doing so test the stability of the PTF, during perturbations of rCBF induced by visual stimulation. Eight dynamic PET scans were acquired per subject (n = 8), each for a duration...... of 6 minutes after IV bolus injection of H2(15)O. Four of these scans were performed using 2D and four using 3D acquisition. Visual stimulation was presented in four scans, and four scans were during rest. Model C was found optimal based on Akaike's Information Criteria (AIC) and had the smallest...

  13. Binding assays for the quantitative detection of P. brevis polyether neurotoxins in biological samples and antibodies as therapeutic aids for polyether marine intoxication. Annual report, 1 December 1987-30 November 1988

    Energy Technology Data Exchange (ETDEWEB)

    Baden, D.G.

    1988-12-15

    The polyether lipid-soluble toxins isolated from the marine dinoflagellate Ptychodiscus brevis (formerly Gymnodinium breve) can be detected using two separate types of specific binding reaction. Using tritiated PbTx-3 as a specific probe for binding to voltage-dependent sodium channels in rat brain synaptosomes or to specific polyclonal antibodies, binding equilibria and displacement by unlabeled brevetoxins were compared. Labeled toxin can be displaced in a competitive manner by any of the other 5 naturally-occurring toxins; the quantitative displacement ability of each appears to reflect individual potency in fish bioassay. A comparison of ED50 in Radioimmunoassay and ED50 in synaptosome binding assay indicates that the former assay is useful for detection of toxins which possess the structural backbone of PbTx-3, the immunizing hapten. Thus, the two assays have quantitative applicability; the sodium channel with respect to potency and the antibodies with respect to structure. Microtiter plate assays utilizing each specific brevetoxin binding component and enzyme-linked toxin hapten have been successful and indicate a general applicability of colorimetric prototypes. There, is however, considerable manipulation required to decrease non-specific binding of the hydrophobic toxin-enzyme complex to the plates. Preliminary studies aimed at producing monoclonal antibodies have been explored using brevetoxins linked to keyhole limpet hemocyanin.

  14. Mathematical biology

    CERN Document Server

    Murray, James D

    1993-01-01

    The book is a textbook (with many exercises) giving an in-depth account of the practical use of mathematical modelling in the biomedical sciences. The mathematical level required is generally not high and the emphasis is on what is required to solve the real biological problem. The subject matter is drawn, e.g. from population biology, reaction kinetics, biological oscillators and switches, Belousov-Zhabotinskii reaction, reaction-diffusion theory, biological wave phenomena, central pattern generators, neural models, spread of epidemics, mechanochemical theory of biological pattern formation and importance in evolution. Most of the models are based on real biological problems and the predictions and explanations offered as a direct result of mathematical analysis of the models are important aspects of the book. The aim is to provide a thorough training in practical mathematical biology and to show how exciting and novel mathematical challenges arise from a genuine interdisciplinary involvement with the biosci...

  15. Other relevant biological papers

    International Nuclear Information System (INIS)

    Shimizu, M.

    1989-01-01

    A considerable number of CRESP-relevant papers concerning deep-sea biology and radioecology have been published. It is the purpose of this study to call attention to them. They fall into three general categories. The first is papers of general interest. They are mentioned only briefly, and include text references to the global bibliography at the end of the volume. The second are papers that are not only mentioned and referenced, but for various reasons are described in abstract form. The last is a list of papers compiled by H.S.J. Roe specifically for this volume. They are listed in bibliographic form, and are also included in the global bibliography at the end of the volume

  16. Application of dried-droplets deposited on pre-cut filter paper disks for quantitative LA-ICP-MS imaging of biologically relevant minor and trace elements in tissue samples.

    Science.gov (United States)

    Bonta, Maximilian; Hegedus, Balazs; Limbeck, Andreas

    2016-02-18

    In this work, a novel calibration approach for minor and trace element quantification in LA-ICP-MS imaging of biological tissues is presented. Droplets of aqueous standard solutions are deposited onto pre-cut pieces of filter paper, allowed to dry, and sputtered with a thin gold layer for use as pseudo-internal standard. Analysis of the standards using LA-ICP-MS is performed using radial line-scans across the filters. In contrast to conventionally used preparation of matrix-matched tissue standards, the dried-droplet approach offers a variety of advantages: The standards are easy to prepare, no characterization of the standards using acid digestion is required, no handling of biological materials is necessary, and the concentration range, as well the number of investigated analytes is almost unlimited. The proposed quantification method has been verified using homogenized tissue standards with known analyte concentrations before being applied to a human malignant mesothelioma biopsy from a patient who had not received any chemotherapeutic treatment. Elemental distribution images were acquired at a lateral resolution of 40 μm per pixel, limits of detection ranging from 0.1 μg g(-1) (Mn, Ni, Cu, Zn) to 13.2 μg g(-1) (K) were reached. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Quantitative analysis of cardiac function: Comparison of electrocardiogram dual gated single photon emission tomography, planar radionuclide ventriculogram and contrast ventriculography in the determination of LV volume and ejection fraction

    Energy Technology Data Exchange (ETDEWEB)

    Ziada, G.; Abdel-Dayem, H.M.; Higazy, E.; Mohamed, M.M.; Bahar, R.; Hayat, N.; Yousof, A.M.

    1987-03-01

    A dual gated tomography (DGT) program for end systolic and end diastolic acquisition and subsequent processing for calculation of LVEF, end diastolic and end systolic volumes (EDV, ESV) has been evaluated in 20 healthy volunteers (25 years-40 years) and 45 patients (25 years-60 years): 20 with ischaemic heart disease and 25 with valvular heart disease (VHD). All had biplane multigated blood pool (MUGA) studies in the 40/sup 0/ LAO projection using in vivo /sup 99m/Tc-R BCs, immediately followed by DG. The results in the patients group were correlated with contrast ventriculography (CV). In the volunteer group, the normal values for LVEF, EDV and ESV measured with DGT were found to be 63%+10%, 91 ml + 6 ml and 30 ml + 6ml and r value for the LVEF=0.91 compared with MUGA. In the IHD group, r values compared with CV were 0.915 and 0.97 for the EDV and ESV and 0.934 for the LVEF. Compared with the MUGA, the r value for LVEF was 0.883. In the VHD group, r values were 0.98 for both the EDV and ESV and 0.948 for the LVEF (P<0.002) compared with CV and 0.789 for the LVEF compared with the MUGA. We feel that DGT is an accurate and reproducible technique for LV function measurements.

  18. Análisis cuantitativo de la investigación en invasiones biológicas en Chile: tendencias y desafíos Quantitative analysis of the research in biological invasions in Chile: Trends and challenges

    Directory of Open Access Journals (Sweden)

    CONSTANZA L QUIROZ

    2009-12-01

    Full Text Available En las últimas dos décadas, el estudio de las invasiones biológicas ha alcanzado un auge sin precedentes a nivel mundial tanto en sus dimensiones teóricas como aplicadas. En Chile, las invasiones biológicas parecieran ser un tema relativamente nuevo. En este artículo se evalúa la tendencia en la investigación de invasiones biológicas en Chile entre los años 1991 y 2008. El análisis se realizó en plantas y animales, de acuerdo a las temáticas abarcadas en los estudios, y las aproximaciones metodológicas utilizadas. La serie temporal de trabajos publicados en invasiones biológicas en Chile está relacionada significativamente con la tendencia de publicaciones sobre invasiones biológicas a nivel mundial. La mayoría de los estudios en Chile se enfocaron en la etapa de invasión de especies introducidas, seguida por las etapas de naturalización de especies y finalmente de introducción. El estudio de patrones de invasión ha sido evaluado con mayor frecuencia en plantas introducidas que en animales, mientras que el estudio del impacto de especies introducidas muestra la tendencia contraria. La mayor parte de los estudios realizados tanto en plantas como animales introducidos se ejecutaron a partir de muéstreos, seguidos por estudios experimentales. Concluimos que existen aún importantes desafíos para los investigadores enfocados en el tema de invasiones biológicas, incluyendo: 1 no solo buscar describir patrones sino también entender procesos detrás de estos patrones, 2 incorporar más estudios experimentales, especialmente enfocados a la evaluación de impactos, 3 mejorar la integración de los estudios a la conservación y restauración de ecosistemas, y 4 intentar conectar los estudios locales a los actuales marcos conceptuales.During the last decades, the study of biological invasions has reached an unforeseeable peak both in the theoretical and applied dimensions. In this article, we assess the trends in research on

  19. Using Live-Crown Ratio to Control Wood Quality: An Example of Quantitative Silviculture

    Science.gov (United States)

    Thomas J. Dean

    1999-01-01

    Quantitative silviculture is the application of biological relationships in meeting specific, quantitative management objectives. It is a two-sided approach requiring the identification and application of biological relationships. An example of quantitative silviculture is presented that uses a relationship between average-live crown ratio and relative stand density...

  20. Theory and Practice in Quantitative Genetics

    DEFF Research Database (Denmark)

    Posthuma, Daniëlle; Beem, A Leo; de Geus, Eco J C

    2003-01-01

    With the rapid advances in molecular biology, the near completion of the human genome, the development of appropriate statistical genetic methods and the availability of the necessary computing power, the identification of quantitative trait loci has now become a realistic prospect for quantitative...... geneticists. We briefly describe the theoretical biometrical foundations underlying quantitative genetics. These theoretical underpinnings are translated into mathematical equations that allow the assessment of the contribution of observed (using DNA samples) and unobserved (using known genetic relationships......) genetic variation to population variance in quantitative traits. Several statistical models for quantitative genetic analyses are described, such as models for the classical twin design, multivariate and longitudinal genetic analyses, extended twin analyses, and linkage and association analyses. For each...

  1. Biological therapeutics

    National Research Council Canada - National Science Library

    Greenstein, Ben; Brook, Daniel A

    2011-01-01

    This introductory textbook covers all the main categories of biological medicines, including vaccines, hormonal preparations, drugs for rheumatoid arthritis and other connective tissue diseases, drugs...

  2. Quantitative Psychology Research : The 80th Annual Meeting of the Psychometric Society, Beijing, 2015

    NARCIS (Netherlands)

    van der Ark, L.A.; Bolt, D.M.; Wang, W.-C.; Douglas, J.A.; Wiberg, M.

    2016-01-01

    The research articles in this volume cover timely quantitative psychology topics, including new methods in item response theory, computerized adaptive testing, cognitive diagnostic modeling, and psychological scaling. Topics within general quantitative methodology include structural equation

  3. Is synthetic biology mechanical biology?

    Science.gov (United States)

    Holm, Sune

    2015-12-01

    A widespread and influential characterization of synthetic biology emphasizes that synthetic biology is the application of engineering principles to living systems. Furthermore, there is a strong tendency to express the engineering approach to organisms in terms of what seems to be an ontological claim: organisms are machines. In the paper I investigate the ontological and heuristic significance of the machine analogy in synthetic biology. I argue that the use of the machine analogy and the aim of producing rationally designed organisms does not necessarily imply a commitment to mechanical biology. The ideal of applying engineering principles to biology is best understood as expressing recognition of the machine-unlikeness of natural organisms and the limits of human cognition. The paper suggests an interpretation of the identification of organisms with machines in synthetic biology according to which it expresses a strategy for representing, understanding, and constructing living systems that are more machine-like than natural organisms.

  4. Biological and technological characteristics of Georgian wine and table grapes

    Directory of Open Access Journals (Sweden)

    Ujmajuridze Levan

    2015-01-01

    Description of grapevine varieties implemented through the descriptors for grapevine (IPGRI OIV. Botanical, biological-technological, qualitative and quantitative marks are characterized and evaluated. Investigation conducted during the biologic development phases were studied for chemical and eno-carpological characteristics.

  5. Quantitative investment analysis

    CERN Document Server

    DeFusco, Richard

    2007-01-01

    In the "Second Edition" of "Quantitative Investment Analysis," financial experts Richard DeFusco, Dennis McLeavey, Jerald Pinto, and David Runkle outline the tools and techniques needed to understand and apply quantitative methods to today's investment process.

  6. Computational biology

    DEFF Research Database (Denmark)

    Hartmann, Lars Røeboe; Jones, Neil; Simonsen, Jakob Grue

    2011-01-01

    Computation via biological devices has been the subject of close scrutiny since von Neumann’s early work some 60 years ago. In spite of the many relevant works in this field, the notion of programming biological devices seems to be, at best, ill-defined. While many devices are claimed or proved t...

  7. Mesoscopic biology

    Indian Academy of Sciences (India)

    In this paper we present a qualitative outlook of mesoscopic biology where the typical length scale is of the order of nanometers and the energy scales comparable to thermal energy. Novel biomolecular machines, governed by coded information at the level of DNA and proteins, operate at these length scales in biological ...

  8. Rigour in quantitative research.

    Science.gov (United States)

    Claydon, Leica Sarah

    2015-07-22

    This article which forms part of the research series addresses scientific rigour in quantitative research. It explores the basis and use of quantitative research and the nature of scientific rigour. It examines how the reader may determine whether quantitative research results are accurate, the questions that should be asked to determine accuracy and the checklists that may be used in this process. Quantitative research has advantages in nursing, since it can provide numerical data to help answer questions encountered in everyday practice.

  9. Organ volume estimation using SPECT

    CERN Document Server

    Zaidi, H

    1996-01-01

    Knowledge of in vivo thyroid volume has both diagnostic and therapeutic importance and could lead to a more precise quantification of absolute activity contained in the thyroid gland. In order to improve single-photon emission computed tomography (SPECT) quantitation, attenuation correction was performed according to Chang's algorithm. The dual-window method was used for scatter subtraction. We used a Monte Carlo simulation of the SPECT system to accurately determine the scatter multiplier factor k. Volume estimation using SPECT was performed by summing up the volume elements (voxels) lying within the contour of the object, determined by a fixed threshold and the gray level histogram (GLH) method. Thyroid phantom and patient studies were performed and the influence of 1) fixed thresholding, 2) automatic thresholding, 3) attenuation, 4) scatter, and 5) reconstruction filter were investigated. This study shows that accurate volume estimation of the thyroid gland is feasible when accurate corrections are perform...

  10. Quantitation: clinical applications

    International Nuclear Information System (INIS)

    Britton, K.E.

    1982-01-01

    Single photon emission tomography may be used quantitatively if its limitations are recognized and quantitation is made in relation to some reference area on the image. Relative quantitation is discussed in outline in relation to the liver, brain and pituitary, thyroid, adrenals, and heart. (U.K.)

  11. Neutron Scattering in Biology Techniques and Applications

    CERN Document Server

    Fitter, Jörg; Katsaras, John

    2006-01-01

    The advent of new neutron facilities and the improvement of existing sources and instruments world wide supply the biological community with many new opportunities in the areas of structural biology and biological physics. The present volume offers a clear description of the various neutron-scattering techniques currently being used to answer biologically relevant questions. Their utility is illustrated through examples by some of the leading researchers in the field of neutron scattering. This volume will be a reference for researchers and a step-by-step guide for young scientists entering the field and the advanced graduate student.

  12. Quantum Biology

    Directory of Open Access Journals (Sweden)

    Alessandro Sergi

    2009-06-01

    Full Text Available A critical assessment of the recent developmentsof molecular biology is presented.The thesis that they do not lead to a conceptualunderstanding of life and biological systems is defended.Maturana and Varela's concept of autopoiesis is briefly sketchedand its logical circularity avoided by postulatingthe existence of underlying living processes,entailing amplification from the microscopic to the macroscopic scale,with increasing complexity in the passage from one scale to the other.Following such a line of thought, the currently accepted model of condensed matter, which is based on electrostatics and short-ranged forces,is criticized. It is suggested that the correct interpretationof quantum dispersion forces (van der Waals, hydrogen bonding, and so onas quantum coherence effects hints at the necessity of includinglong-ranged forces (or mechanisms for them incondensed matter theories of biological processes.Some quantum effects in biology are reviewedand quantum mechanics is acknowledged as conceptually important to biology since withoutit most (if not all of the biological structuresand signalling processes would not even exist. Moreover, it is suggested that long-rangequantum coherent dynamics, including electron polarization,may be invoked to explain signal amplificationprocess in biological systems in general.

  13. Biological desulfurisation

    Energy Technology Data Exchange (ETDEWEB)

    Arena, B.J. [UOP LLC (United States); Benschop, A.; Janssen, A. [Paques Natural Solutions (Netherlands); Kijlstra, S. [Shell Global Solutions (Netherlands)

    2001-03-01

    This article focuses on the biological THIOPAQ process for removing hydrogen sulphide from refinery gases and recovering elemental sulphur. Details are given of the process which absorbs hydrogen sulphide-containing gas in alkaline solution prior to oxidation of the dissolved sulphur to elemental sulphur in a THIOPAQ aerobic biological reactor, with regeneration of the caustic solution. Sulphur handling options including sulphur wash, the drying of the sulphur cake, and sulphur smelting by pressure liquefaction are described. Agricultural applications of the biologically recovered sulphur, and application of the THIOPAQ process to sulphur recovery are discussed.

  14. Development and applications of quantitative NMR spectroscopy

    International Nuclear Information System (INIS)

    Yamazaki, Taichi

    2016-01-01

    Recently, quantitative NMR spectroscopy has attracted attention as an analytical method which can easily secure traceability to SI unit system, and discussions about its accuracy and inaccuracy are also started. This paper focuses on the literatures on the advancement of quantitative NMR spectroscopy reported between 2009 and 2016, and introduces both NMR measurement conditions and actual analysis cases in quantitative NMR. The quantitative NMR spectroscopy using an internal reference method enables accurate quantitative analysis with a quick and versatile way in general, and it is possible to obtain the precision sufficiently applicable to the evaluation of pure substances and standard solutions. Since the external reference method can easily prevent contamination to samples and the collection of samples, there are many reported cases related to the quantitative analysis of biologically related samples and highly scarce natural products in which NMR spectra are complicated. In the precision of quantitative NMR spectroscopy, the internal reference method is superior. As the quantitative NMR spectroscopy widely spreads, discussions are also progressing on how to utilize this analytical method as the official methods in various countries around the world. In Japan, this method is listed in the Pharmacopoeia and Japanese Standard of Food Additives, and it is also used as the official method for purity evaluation. In the future, this method will be expected to spread as the general-purpose analysis method that can ensure traceability to SI unit system. (A.O.)

  15. Quantitative imaging as cancer biomarker

    Science.gov (United States)

    Mankoff, David A.

    2015-03-01

    The ability to assay tumor biologic features and the impact of drugs on tumor biology is fundamental to drug development. Advances in our ability to measure genomics, gene expression, protein expression, and cellular biology have led to a host of new targets for anticancer drug therapy. In translating new drugs into clinical trials and clinical practice, these same assays serve to identify patients most likely to benefit from specific anticancer treatments. As cancer therapy becomes more individualized and targeted, there is an increasing need to characterize tumors and identify therapeutic targets to select therapy most likely to be successful in treating the individual patient's cancer. Thus far assays to identify cancer therapeutic targets or anticancer drug pharmacodynamics have been based upon in vitro assay of tissue or blood samples. Advances in molecular imaging, particularly PET, have led to the ability to perform quantitative non-invasive molecular assays. Imaging has traditionally relied on structural and anatomic features to detect cancer and determine its extent. More recently, imaging has expanded to include the ability to image regional biochemistry and molecular biology, often termed molecular imaging. Molecular imaging can be considered an in vivo assay technique, capable of measuring regional tumor biology without perturbing it. This makes molecular imaging a unique tool for cancer drug development, complementary to traditional assay methods, and a potentially powerful method for guiding targeted therapy in clinical trials and clinical practice. The ability to quantify, in absolute measures, regional in vivo biologic parameters strongly supports the use of molecular imaging as a tool to guide therapy. This review summarizes current and future applications of quantitative molecular imaging as a biomarker for cancer therapy, including the use of imaging to (1) identify patients whose tumors express a specific therapeutic target; (2) determine

  16. Thematic cartography, cartography and the impact of the quantitative revolution

    CERN Document Server

    Cauvin, Colette; Serradj, Aziz

    2013-01-01

    This series in three volumes considers maps as constructions resulting from a number of successive transformations and stages integrated in a logical reasoning and an order of choices. Volume 2 focuses on the impact of the quantitative revolution, partially related to the advent of the computer age, on thematic cartography.

  17. Genetics and molecular biology of breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    King, M.C. [California Univ., Berkeley, CA (United States); Lippman, M. [Georgetown Univ. Medical Center, Washington, DC (United States)] [comps.

    1992-12-31

    This volume contains the abstracts of oral presentations and poster sessions presented at the Cold Springs Harbor Meeting on Cancer Cells, this meeting entitled Genetics and Molecular Biology of Breast Cancer.

  18. Quantile-Based Permutation Thresholds for Quantitative Trait Loci Hotspots

    NARCIS (Netherlands)

    Neto, Elias Chaibub; Keller, Mark P.; Broman, Andrew F.; Attie, Alan D.; Jansen, Ritsert C.; Broman, Karl W.; Yandell, Brian S.; Borevitz, J.

    Quantitative trait loci (QTL) hotspots (genomic locations affecting many traits) are a common feature in genetical genomics studies and are biologically interesting since they may harbor critical regulators. Therefore, statistical procedures to assess the significance of hotspots are of key

  19. Systems Biology

    Indian Academy of Sciences (India)

    IAS Admin

    study and understand the function of biological systems, particu- larly, the response of such .... understand the organisation and behaviour of prokaryotic sys- tems. ... relationship of the structure of a target molecule to its ability to bind a certain ...

  20. [Progress in stable isotope labeled quantitative proteomics methods].

    Science.gov (United States)

    Zhou, Yuan; Shan, Yichu; Zhang, Lihua; Zhang, Yukui

    2013-06-01

    Quantitative proteomics is an important research field in post-genomics era. There are two strategies for proteome quantification: label-free methods and stable isotope labeling methods which have become the most important strategy for quantitative proteomics at present. In the past few years, a number of quantitative methods have been developed, which support the fast development in biology research. In this work, we discuss the progress in the stable isotope labeling methods for quantitative proteomics including relative and absolute quantitative proteomics, and then give our opinions on the outlook of proteome quantification methods.

  1. Quantitative analysis of oyster larval proteome provides new insights into the effects of multiple climate change stressors, supplement to: Dineshram, R; Chandramouli, K; Ko, W K Ginger; Zhang, Huoming; Qian, Pei Yuan; Ravasi, Timothy; Thiyagarajan, Vengatesen (2016): Quantitative analysis of oyster larval proteome provides new insights into the effects of multiple climate change stressors. Global Change Biology, 22(6), 2054-2068

    KAUST Repository

    Dineshram, R

    2016-01-01

    The metamorphosis of planktonic larvae of the Pacific oyster (Crassostrea gigas) underpins their complex life-history strategy by switching on the molecular machinery required for sessile life and building calcite shells. Metamorphosis becomes a survival bottleneck, which will be pressured by different anthropogenically induced climate change-related variables. Therefore, it is important to understand how metamorphosing larvae interact with emerging climate change stressors. To predict how larvae might be affected in a future ocean, we examined changes in the proteome of metamorphosing larvae under multiple stressors: decreased pH (pH 7.4), increased temperature (30 °C), and reduced salinity (15 psu). Quantitative protein expression profiling using iTRAQ-LC-MS/MS identified more than 1300 proteins. Decreased pH had a negative effect on metamorphosis by down-regulating several proteins involved in energy production, metabolism, and protein synthesis. However, warming switched on these down-regulated pathways at pH 7.4. Under multiple stressors, cell signaling, energy production, growth, and developmental pathways were up-regulated, although metamorphosis was still reduced. Despite the lack of lethal effects, significant physiological responses to both individual and interacting climate change related stressors were observed at proteome level. The metamorphosing larvae of the C. gigas population in the Yellow Sea appear to have adequate phenotypic plasticity at the proteome level to survive in future coastal oceans, but with developmental and physiological costs.

  2. Microfluidic devices for biological applications

    CSIR Research Space (South Africa)

    Potgieter, S

    2010-01-01

    Full Text Available Microfluidics is a multi-disciplinary field that deals with the behaviour, control and manipulation of fluids constrained to sub-millilitre volumes. It is proving to be a useful tool for biological studies, affording advantages such as reduced cost...

  3. Determination of left ventricular heart volume by fast MRI in breath-hold technique: how different are quantitative ventricular angiography, quantitative MRI, and visual echocardiography?; Linksventrikulaere Herzvoluminabestimmung mittels schneller MRT in Atemanhaltetechnik: Wie unterschiedlich sind quantitativer Herzkatheter, quantitativer MRT und visuelle Echokardiographie?

    Energy Technology Data Exchange (ETDEWEB)

    Rominger, M.B.; Bachmann, G.F. [Giessen Univ. (Germany). Diagnostische Radiologie; Kerckhoff-Klinik GmbH, Bad Nauheim (Germany). Projektgruppe Magnetresonanztomographie; Pabst, W. [Giessen Univ. (Germany). Inst. fuer Medizinische Informatik; Ricken, W.W. [Kerckhoff-Klinik GmbH, Bad Nauheim (Germany). Projektgruppe Magnetresonanztomographie; Dinkel, H.P.; Rau, W.S. [Giessen Univ. (Germany). Diagnostische Radiologie

    2000-01-01

    Goal: Comparison of fast MRI, echocardiography (Echo), and ventricular angiography (Cath) in the assessment of left ventricular global function. Methods: Fast MRI in short axis plane, biplane Cath, and 2D Echo were performed in 62 patients [35 coronary artery diseases, 16 acquired valvular diseases (VD), 9 dilated cardiomyopathies (DCM), 1 congenital heart disease and 1 heart transplantation]. Enddiastolic (EDV), endsystolic (ESV), stroke volumes (SV), cardiac output (CO), and ejection fraction (EF) were compared in MRI and Cath. EF was visually estimated in 2D Echo by an experienced observer. Results: In comparison to MRI, Cath overestimated EF by 8.4%, and Echo underestimated EF by 5.6%. The limits of agreement between MRI and Cath in EF were {+-}23.8%, between MRI and Echo {+-}18%, and between Echo and Cath {+-}19.4%. Significant differences were found between Cath and MRI in EDV, SV, and CO, but not for ESV. The best agreement in EF was found in the group with DCM, the worst in the group with VD. Conclusion: Important systemic and random errors were found in the comparison of MRI, Echo, and Cath. For therapy decision and follow-up, the methods should not be exchanged unscrupulously. (orig.) [German] Ziel: Methodenvergleich von schneller Magnetresonanztomographie (MRT), Echokardiographie (Echo) und Herzkatheter (HK) in der Bestimmung linksventrikulaerer globaler Funktionsparameter. Material und Methoden: Bei 62 Patienten (35 koronare Herzerkrankungen, 16 Herzklappenvitien (KV), 9 idiopathische dilatative Kardiomyopathien (DCM), 1 kongenitale Herzerkrankung und 1 Herzktransplantation) wurde ein Methodenvergleich zwischen schneller Cine MRT im Kurzachsenschnitt, biplanarem HK und 2D Echo durchgefuehrt. Verglichen wurden in MRT und HK linksventrikulaeres enddiastolisches (EDV) und endsystolisches Volumen (ESV), Schlagvolumen (SV), Herzzeitvolumen (HZV) und Ejektionsfraktion (EF). In der Echo wurde die EF visuell durch einen erfahrenen Untersucher bestimmt

  4. Structural Biology: Practical NMR Applications

    CERN Document Server

    Teng, Quincy

    2005-01-01

    This textbook begins with an overview of NMR development and applications in biological systems. It describes recent developments in instrument hardware and methodology. Chapters highlight the scope and limitation of NMR methods. While detailed math and quantum mechanics dealing with NMR theory have been addressed in several well-known NMR volumes, chapter two of this volume illustrates the fundamental principles and concepts of NMR spectroscopy in a more descriptive manner. Topics such as instrument setup, data acquisition, and data processing using a variety of offline software are discussed. Chapters further discuss several routine stategies for preparing samples, especially for macromolecules and complexes. The target market for such a volume includes researchers in the field of biochemistry, chemistry, structural biology and biophysics.

  5. Quantitative analysis chemistry

    International Nuclear Information System (INIS)

    Ko, Wansuk; Lee, Choongyoung; Jun, Kwangsik; Hwang, Taeksung

    1995-02-01

    This book is about quantitative analysis chemistry. It is divided into ten chapters, which deal with the basic conception of material with the meaning of analysis chemistry and SI units, chemical equilibrium, basic preparation for quantitative analysis, introduction of volumetric analysis, acid-base titration of outline and experiment examples, chelate titration, oxidation-reduction titration with introduction, titration curve, and diazotization titration, precipitation titration, electrometric titration and quantitative analysis.

  6. Review of progress in quantitative nondestructive evaluation

    International Nuclear Information System (INIS)

    Thompson, D.O.; Chimenti, D.E.

    1983-01-01

    A comprehensive review of the current state of quantitative nondestructive evaluation (NDE), this volume brings together papers by researchers working in government, private industry, and university laboratories. Their papers cover a wide range of interests and concerns for researchers involved in theoretical and applied aspects of quantitative NDE. Specific topics examined include reliability probability of detection--ultrasonics and eddy currents weldments closure effects in fatigue cracks technology transfer ultrasonic scattering theory acoustic emission ultrasonic scattering, reliability and penetrating radiation metal matrix composites ultrasonic scattering from near-surface flaws ultrasonic multiple scattering

  7. Bare-Hand Volume Cracker for Raw Volume Data Analysis

    Directory of Open Access Journals (Sweden)

    Bireswar Laha

    2016-09-01

    Full Text Available Analysis of raw volume data generated from different scanning technologies faces a variety of challenges, related to search, pattern recognition, spatial understanding, quantitative estimation, and shape description. In a previous study, we found that the Volume Cracker (VC 3D interaction (3DI technique mitigated some of these problems, but this result was from a tethered glove-based system with users analyzing simulated data. Here, we redesigned the VC by using untethered bare-hand interaction with real volume datasets, with a broader aim of adoption of this technique in research labs. We developed symmetric and asymmetric interfaces for the Bare-Hand Volume Cracker (BHVC through design iterations with a biomechanics scientist. We evaluated our asymmetric BHVC technique against standard 2D and widely used 3D interaction techniques with experts analyzing scanned beetle datasets. We found that our BHVC design significantly outperformed the other two techniques. This study contributes a practical 3DI design for scientists, documents lessons learned while redesigning for bare-hand trackers, and provides evidence suggesting that 3D interaction could improve volume data analysis for a variety of visual analysis tasks. Our contribution is in the realm of 3D user interfaces tightly integrated with visualization, for improving the effectiveness of visual analysis of volume datasets. Based on our experience, we also provide some insights into hardware-agnostic principles for design of effective interaction techniques.

  8. Quantitative Algebraic Reasoning

    DEFF Research Database (Denmark)

    Mardare, Radu Iulian; Panangaden, Prakash; Plotkin, Gordon

    2016-01-01

    We develop a quantitative analogue of equational reasoning which we call quantitative algebra. We define an equality relation indexed by rationals: a =ε b which we think of as saying that “a is approximately equal to b up to an error of ε”. We have 4 interesting examples where we have a quantitative...... equational theory whose free algebras correspond to well known structures. In each case we have finitary and continuous versions. The four cases are: Hausdorff metrics from quantitive semilattices; pWasserstein metrics (hence also the Kantorovich metric) from barycentric algebras and also from pointed...

  9. Quantitative autoradiography of neurochemicals

    International Nuclear Information System (INIS)

    Rainbow, T.C.; Biegon, A.; Bleisch, W.V.

    1982-01-01

    Several new methods have been developed that apply quantitative autoradiography to neurochemistry. These methods are derived from the 2-deoxyglucose (2DG) technique of Sokoloff (1), which uses quantitative autoradiography to measure the rate of glucose utilization in brain structures. The new methods allow the measurement of the rate of cerbral protein synthesis and the levels of particular neurotransmitter receptors by quantitative autoradiography. As with the 2DG method, the new techniques can measure molecular levels in micron-sized brain structures; and can be used in conjunction with computerized systems of image processing. It is possible that many neurochemical measurements could be made by computerized analysis of quantitative autoradiograms

  10. The Central Dogma of Molecular Biology

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 14; Issue 3. The Central Dogma of Molecular Biology - A Retrospective after Fifty Years. Michel Morange. General Article Volume 14 Issue 3 March 2009 pp 236-247. Fulltext. Click here to view fulltext PDF. Permanent link:

  11. Biological Art of Producing Useful Chemicals

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 21; Issue 3. Metabolic Engineering: Biological Art of Producing Useful Chemicals. Ram Kulkarni. General Article Volume 21 Issue 3 March 2016 pp 233-237. Fulltext. Click here to view fulltext PDF. Permanent link:

  12. Science Academies' Refresher Course in Developmental Biology

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 20; Issue 8. Science Academies' Refresher Course in Developmental Biology. Information and Announcements Volume 20 Issue 8 August 2015 pp 756-756. Fulltext. Click here to view fulltext PDF. Permanent link:

  13. [Biological agents].

    Science.gov (United States)

    Amano, Koichi

    2009-03-01

    There are two types of biological agents for the treatment of rheumatoid arthritis (RA); monoclonal antibodies and recombinant proteins. Among the latter, etanercept, a recombinant fusion protein of soluble TNF receptor and IgG was approved in 2005 in Japan. The post-marketing surveillance of 13,894 RA patients revealed the efficacy and safety profiles of etanercept in the Japanese population, as well as overseas studies. Abatacept, a recombinant fusion protein of CTLA4 and IgG, is another biological agent for RA. Two clinical trials disclosed the efficacy of abatacept for difficult-to-treat patients: the AIM for MTX-resistant cases and the ATTAIN for patients who are resistant to anti-TNF. The ATTEST trial suggested abatacept might have more acceptable safety profile than infliximab. These biologics are also promising for the treatment of RA for not only relieving clinical symptoms and signs but retarding structural damage.

  14. Biological preconcentrator

    Science.gov (United States)

    Manginell, Ronald P [Albuquerque, NM; Bunker, Bruce C [Albuquerque, NM; Huber, Dale L [Albuquerque, NM

    2008-09-09

    A biological preconcentrator comprises a stimulus-responsive active film on a stimulus-producing microfabricated platform. The active film can comprise a thermally switchable polymer film that can be used to selectively absorb and desorb proteins from a protein mixture. The biological microfabricated platform can comprise a thin membrane suspended on a substrate with an integral resistive heater and/or thermoelectric cooler for thermal switching of the active polymer film disposed on the membrane. The active polymer film can comprise hydrogel-like polymers, such as poly(ethylene oxide) or poly(n-isopropylacrylamide), that are tethered to the membrane. The biological preconcentrator can be fabricated with semiconductor materials and technologies.

  15. Evaluation of Quantitative Environmental Stress Screening (ESS) Methods. Volume 1

    Science.gov (United States)

    1991-11-01

    required information on screening strength from the curvefitting parameters. The underlying theory and approach taken are discussed in Appendix A. To...in field 1020 arm St.,Vas AJ Ptr 0.4i Currpnt. c- ugt ~ing DU?/SYS 2.7264 Wll/IY.3 at Factory Stress- NaxiLMw outgoing W?is’ys 0.288 DrW/5?S at Field...182 125 K.W.Fertig and V.X. Murthy, Models for Reliability Growth During Burn-in: Theory and Applicat’ons,Proceedings 1978 Annual Reliability and

  16. Innovations in Quantitative Risk Management

    CERN Document Server

    Scherer, Matthias; Zagst, Rudi

    2015-01-01

    Quantitative models are omnipresent –but often controversially discussed– in todays risk management practice. New regulations, innovative financial products, and advances in valuation techniques provide a continuous flow of challenging problems for financial engineers and risk managers alike. Designing a sound stochastic model requires finding a careful balance between parsimonious model assumptions, mathematical viability, and interpretability of the output. Moreover, data requirements and the end-user training are to be considered as well. The KPMG Center of Excellence in Risk Management conference Risk Management Reloaded and this proceedings volume contribute to bridging the gap between academia –providing methodological advances– and practice –having a firm understanding of the economic conditions in which a given model is used. Discussed fields of application range from asset management, credit risk, and energy to risk management issues in insurance. Methodologically, dependence modeling...

  17. Fostering synergy between cell biology and systems biology.

    Science.gov (United States)

    Eddy, James A; Funk, Cory C; Price, Nathan D

    2015-08-01

    In the shared pursuit of elucidating detailed mechanisms of cell function, systems biology presents a natural complement to ongoing efforts in cell biology. Systems biology aims to characterize biological systems through integrated and quantitative modeling of cellular information. The process of model building and analysis provides value through synthesizing and cataloging information about cells and molecules, predicting mechanisms and identifying generalizable themes, generating hypotheses and guiding experimental design, and highlighting knowledge gaps and refining understanding. In turn, incorporating domain expertise and experimental data is crucial for building towards whole cell models. An iterative cycle of interaction between cell and systems biologists advances the goals of both fields and establishes a framework for mechanistic understanding of the genome-to-phenome relationship. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  18. Recent trends in social systems quantitative theories and quantitative models

    CERN Document Server

    Hošková-Mayerová, Šárka; Soitu, Daniela-Tatiana; Kacprzyk, Janusz

    2017-01-01

    The papers collected in this volume focus on new perspectives on individuals, society, and science, specifically in the field of socio-economic systems. The book is the result of a scientific collaboration among experts from “Alexandru Ioan Cuza” University of Iaşi (Romania), “G. d’Annunzio” University of Chieti-Pescara (Italy), "University of Defence" of Brno (Czech Republic), and "Pablo de Olavide" University of Sevilla (Spain). The heterogeneity of the contributions presented in this volume reflects the variety and complexity of social phenomena. The book is divided in four Sections as follows. The first Section deals with recent trends in social decisions. Specifically, it aims to understand which are the driving forces of social decisions. The second Section focuses on the social and public sphere. Indeed, it is oriented on recent developments in social systems and control. Trends in quantitative theories and models are described in Section 3, where many new formal, mathematical-statistical to...

  19. Understanding Biological Regulation Through Synthetic Biology.

    Science.gov (United States)

    Bashor, Caleb J; Collins, James J

    2018-03-16

    Engineering synthetic gene regulatory circuits proceeds through iterative cycles of design, building, and testing. Initial circuit designs must rely on often-incomplete models of regulation established by fields of reductive inquiry-biochemistry and molecular and systems biology. As differences in designed and experimentally observed circuit behavior are inevitably encountered, investigated, and resolved, each turn of the engineering cycle can force a resynthesis in understanding of natural network function. Here, we outline research that uses the process of gene circuit engineering to advance biological discovery. Synthetic gene circuit engineering research has not only refined our understanding of cellular regulation but furnished biologists with a toolkit that can be directed at natural systems to exact precision manipulation of network structure. As we discuss, using circuit engineering to predictively reorganize, rewire, and reconstruct cellular regulation serves as the ultimate means of testing and understanding how cellular phenotype emerges from systems-level network function. Expected final online publication date for the Annual Review of Biophysics Volume 47 is May 20, 2018. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

  20. Environmental biology

    International Nuclear Information System (INIS)

    Tschumi, P.A.

    1981-01-01

    Environmental biology illustrates the functioning of ecosystems and the dynamics of populations with many examples from limnology and terrestrial ecology. On this basis, present environmental problems are analyzed. The present environmental crisis is seen as a result of the failure to observe ecological laws. (orig.) [de

  1. Biological timekeeping

    DEFF Research Database (Denmark)

    Lloyd, David

    2016-01-01

    , the networks that connect differenttime domains and the oscillations, rhythms and biological clocks that coordinate andsynchronise the complexity of the living state.“It is the pattern maintained by this homeostasis, which is the touchstone ofour personal identity. Our tissues change as we live: the food we...

  2. Scaffolded biology.

    Science.gov (United States)

    Minelli, Alessandro

    2016-09-01

    Descriptions and interpretations of the natural world are dominated by dichotomies such as organism vs. environment, nature vs. nurture, genetic vs. epigenetic, but in the last couple of decades strong dissatisfaction with those partitions has been repeatedly voiced and a number of alternative perspectives have been suggested, from perspectives such as Dawkins' extended phenotype, Turner's extended organism, Oyama's Developmental Systems Theory and Odling-Smee's niche construction theory. Last in time is the description of biological phenomena in terms of hybrids between an organism (scaffolded system) and a living or non-living scaffold, forming unit systems to study processes such as reproduction and development. As scaffold, eventually, we can define any resource used by the biological system, especially in development and reproduction, without incorporating it as happens in the case of resources fueling metabolism. Addressing biological systems as functionally scaffolded systems may help pointing to functional relationships that can impart temporal marking to the developmental process and thus explain its irreversibility; revisiting the boundary between development and metabolism and also regeneration phenomena, by suggesting a conceptual framework within which to investigate phenomena of regular hypermorphic regeneration such as characteristic of deer antlers; fixing a periodization of development in terms of the times at which a scaffolding relationship begins or is terminated; and promoting plant galls to legitimate study objects of developmental biology.

  3. Biological digestion

    International Nuclear Information System (INIS)

    Rosevear, A.

    1988-01-01

    This paper discusses the biological degradation of non-radioactive organic material occurring in radioactive wastes. The biochemical steps are often performed using microbes or isolated enzymes in combination with chemical steps and the aim is to oxidise the carbon, hydrogen, nitrogen and sulphur to their respective oxides. (U.K.)

  4. Marine Biology

    Science.gov (United States)

    Dewees, Christopher M.; Hooper, Jon K.

    1976-01-01

    A variety of informational material for a course in marine biology or oceanology at the secondary level is presented. Among the topics discussed are: food webs and pyramids, planktonic blooms, marine life, plankton nets, food chains, phytoplankton, zooplankton, larval plankton and filter feeders. (BT)

  5. Clinostats and centrifuges: Their use, value, and limitations in gravitational biological research; Symposium, Washington, Oct. 19, 1991, Report

    Science.gov (United States)

    Halstead, Thora W. (Editor); Todd, Paul (Editor); Powers, Janet V. (Editor)

    1992-01-01

    The present volume addresses physical phenomena and effects associated with clinostat and centrifuge operations as well as their physiological effects. Particular attention is given to the simulation of the gravity conditions on the ground, the internal dynamics of slowly rotating biological systems, and qualitative and quantitative aspects of the fast-rotating clinostat as a research tool. Also discussed are the development and use of centrifuges in gravitational biology, the use of centrifuges in plant gravitational biology and a comparison of ground-based and flight experiment results, the ability of clinostat to mimic the effect of microgravity on plant cells and organs, and the impact of altered gravity conditions on early EGF-induced signal transduction in human epidermal A431 cells.

  6. CASPIAN BIOLOGICAL RESOURCES

    Directory of Open Access Journals (Sweden)

    M. K. Guseynov

    2015-01-01

    Full Text Available Aim. We present the data on the biological resources of the Caspian Sea, based on the analysis of numerous scientific sources published between years of 1965 and 2011. Due to changes in various biotic and abiotic factors we find it important to discuss the state of the major groups of aquatic biocenosis including algae, crayfish, shrimp, pontogammarus, fish and Caspian seal. Methods. Long-term data has been analyzed on the biology and ecology of the main commercial fish stocks and their projected catches for qualitative and quantitative composition, abundance and biomass of aquatic organisms that make up the food base for fish. Results and discussion. It has been found that the widespread commercial invertebrates in the Caspian Sea are still poorly studied; their stocks are not identified and not used commercially. There is a great concern about the current state of the main commercial fish stocks of the Caspian Sea. A critical challenge is to preserve the pool of biological resources and the restoration of commercial stocks of Caspian fish. For more information about the state of the marine ecosystem in modern conditions, expedition on Caspian Sea should be carried out to study the hydrochemical regime and fish stocks, assessment of sturgeon stocks, as well as the need to conduct sonar survey for sprat stocks. Conclusions. The main condition for preserving the ecosystem of the Caspian Sea and its unique biological resources is to develop and apply environmentally-friendly methods of oil, issuing concerted common fisheries rules in various regions of theCaspian Sea, strengthening of control for sturgeon by all Caspian littoral states. The basic principle of the protection of biological resources is their rational use, based on the preservation of optimal conditions of their natural or artificial reproduction. 

  7. Heuristic Strategies in Systems Biology

    Directory of Open Access Journals (Sweden)

    Fridolin Gross

    2016-06-01

    Full Text Available Systems biology is sometimes presented as providing a superior approach to the problem of biological complexity. Its use of ‘unbiased’ methods and formal quantitative tools might lead to the impression that the human factor is effectively eliminated. However, a closer look reveals that this impression is misguided. Systems biologists cannot simply assemble molecular information and compute biological behavior. Instead, systems biology’s main contribution is to accelerate the discovery of mechanisms by applying models as heuristic tools. These models rely on a variety of idealizing and simplifying assumptions in order to be efficient for this purpose. The strategies of systems biologists are similar to those of experimentalists in that they attempt to reduce the complexity of the discovery process. Analyzing and comparing these strategies, or ‘heuristics’, reveals the importance of the human factor in computational approaches and helps to situate systems biology within the epistemic landscape of the life sciences.

  8. Digital radiography: a quantitative approach

    International Nuclear Information System (INIS)

    Retraint, F.

    2004-01-01

    'Full-text:' In a radiograph the value of each pixel is related to the material thickness crossed by the x-rays. Using this relationship, an object can be characterized by parameters such as depth, surface and volume. Assuming a locally linear detector response and using a radiograph of reference object, the quantitative thickness map of object can be obtained by applying offset and gain corrections. However, for an acquisition system composed of cooled CCD camera optically coupled to a scintillator screen, the radiographic image formation process generates some bias which prevent from obtaining the quantitative information: non uniformity of the x-ray source, beam hardening, Compton scattering, scintillator screen, optical system response. In a first section, we propose a complete model of the radiographic image formation process taking account of these biases. In a second section, we present an inversion scheme of this model for a single material object, which enables to obtain the thickness map of the object crossed by the x-rays. (author)

  9. A short note on the paper of Liu et al. (2012). A relative Lempel-Ziv complexity: Application to comparing biological sequences. Chemical Physics Letters, volume 530, 19 March 2012, pages 107-112

    Science.gov (United States)

    Arit, Turkan; Keskin, Burak; Firuzan, Esin; Cavas, Cagin Kandemir; Liu, Liwei; Cavas, Levent

    2018-04-01

    The report entitled "L. Liu, D. Li, F. Bai, A relative Lempel-Ziv complexity: Application to comparing biological sequences, Chem. Phys. Lett. 530 (2012) 107-112" mentions on the powerful construction of phylogenetic trees based on Lempel-Ziv algorithm. On the other hand, the method explained in the paper does not give promising result on the data set on invasive Caulerpa taxifolia in the Mediterranean Sea. The phylogenetic trees are obtained by the proposed method of the aforementioned paper in this short note.

  10. Optimization of the biological process using flat membrane bioreactors. Maximum treatment performance with minimum reactor volume; Optimizacion del proceso biologico con BRM de membrana plana. Maximo rendimiento de depuracion con minimo volumen de reactor

    Energy Technology Data Exchange (ETDEWEB)

    Lluch Vallmithana, S.; Lopez Gavin, A.

    2006-07-01

    In a conventional activated sludge process, the membranes are inside the biological reactor where they drain the water through suction or a water column. This system can be operated with heavy loads and sludge of 12-14 g/l or more, and is not affected by problems of bulking or foaming. This makes it suitable for treating difficult industrial waste waters, providing treated water that is free of bacteria and viruses. Micro filtration membranes are flat without any rubbing between them. The membranes require infrequent chemical cleaning and do not need back washing. As no final sedimented is needed, the waste water treatment plant occupies less space. (Author)

  11. Biological radioprotector

    International Nuclear Information System (INIS)

    Stefanescu, Ioan; Titescu, Gheorghe; Tamaian, Radu; Haulica, Ion; Bild, Walther

    2002-01-01

    According to the patent description, the biological radioprotector is deuterium depleted water, DDW, produced by vacuum distillation with an isotopic content lower than natural value. It appears as such or in a mixture with natural water and carbon dioxide. It can be used for preventing and reducing the ionizing radiation effects upon humans or animal organisms, exposed therapeutically, professionally or accidentally to radiation. The most significant advantage of using DDW as biological radioprotector results from its way of administration. Indeed no one of the radioprotectors currently used today can be orally administrated, what reduces the patients' compliance to prophylactic administrations. The biological radioprotector is an unnoxious product obtained from natural water, which can be administrated as food additive instead of drinking water. Dose modification factor is according to initial estimates around 1.9, what is a remarkable feature when one takes into account that the product is toxicity-free and side effect-free and can be administrated prophylactically as a food additive. A net radioprotective action of the deuterium depletion was evidenced experimentally in laboratory animals (rats) hydrated with DDW of 30 ppm D/(D+H) concentration as compared with normally hydrated control animals. Knowing the effects of irradiation and mechanisms of the acute radiation disease as well as the effects of administration of radiomimetic chemicals upon cellular lines of fast cell division, it appears that the effects of administrating DDW result from stimulation of the immunity system. In conclusion, the biological radioprotector DDW presents the following advantages: - it is obtained from natural products without toxicity; - it is easy to be administrated as a food additive, replacing the drinking water; - besides radioprotective effects, the product has also immunostimulative and antitumoral effects

  12. Marine biology

    International Nuclear Information System (INIS)

    Thurman, H.V.; Webber, H.H.

    1984-01-01

    This book discusses both taxonomic and ecological topics on marine biology. Full coverage of marine organisms of all five kingdoms is provided, along with interesting and thorough discussion of all major marine habitats. Organization into six major parts allows flexibility. It also provides insight into important topics such as disposal of nuclear waste at sea, the idea that life began on the ocean floor, and how whales, krill, and people interact. A full-color photo chapter reviews questions, and exercises. The contents are: an overview marine biology: fundamental concepts/investigating life in the ocean; the physical ocean, the ocean floor, the nature of water, the nature and motion of ocean water; general ecology, conditions for life in the sea, biological productivity and energy transfer; marine organisms; monera, protista, mycota and metaphyta; the smaller marine animals, the large animals marine habitats, the intertidal zone/benthos of the continental shelf, the photic zone, the deep ocean, the ocean under stress, marine pollution, appendix a: the metric system and conversion factors/ appendix b: prefixes and suffixes/ appendix c: taxonomic classification of common marine organisms, and glossary, and index

  13. Magnetoresistive biosensors for quantitative proteomics

    Science.gov (United States)

    Zhou, Xiahan; Huang, Chih-Cheng; Hall, Drew A.

    2017-08-01

    Quantitative proteomics, as a developing method for study of proteins and identification of diseases, reveals more comprehensive and accurate information of an organism than traditional genomics. A variety of platforms, such as mass spectrometry, optical sensors, electrochemical sensors, magnetic sensors, etc., have been developed for detecting proteins quantitatively. The sandwich immunoassay is widely used as a labeled detection method due to its high specificity and flexibility allowing multiple different types of labels. While optical sensors use enzyme and fluorophore labels to detect proteins with high sensitivity, they often suffer from high background signal and challenges in miniaturization. Magnetic biosensors, including nuclear magnetic resonance sensors, oscillator-based sensors, Hall-effect sensors, and magnetoresistive sensors, use the specific binding events between magnetic nanoparticles (MNPs) and target proteins to measure the analyte concentration. Compared with other biosensing techniques, magnetic sensors take advantage of the intrinsic lack of magnetic signatures in biological samples to achieve high sensitivity and high specificity, and are compatible with semiconductor-based fabrication process to have low-cost and small-size for point-of-care (POC) applications. Although still in the development stage, magnetic biosensing is a promising technique for in-home testing and portable disease monitoring.

  14. Quantitative film radiography

    International Nuclear Information System (INIS)

    Devine, G.; Dobie, D.; Fugina, J.; Hernandez, J.; Logan, C.; Mohr, P.; Moss, R.; Schumacher, B.; Updike, E.; Weirup, D.

    1991-01-01

    We have developed a system of quantitative radiography in order to produce quantitative images displaying homogeneity of parts. The materials that we characterize are synthetic composites and may contain important subtle density variations not discernible by examining a raw film x-radiograph. In order to quantitatively interpret film radiographs, it is necessary to digitize, interpret, and display the images. Our integrated system of quantitative radiography displays accurate, high-resolution pseudo-color images in units of density. We characterize approximately 10,000 parts per year in hundreds of different configurations and compositions with this system. This report discusses: the method; film processor monitoring and control; verifying film and processor performance; and correction of scatter effects

  15. Nuclear magnetic resonance of biological macromolecules part A

    CERN Document Server

    Schmitz, Uli; Schmitz, Uli; Dotsch, Volker

    2001-01-01

    This volume and its companion, Volume 339, supplement Volumes 176, 177, 239, and 261. Chapters are written with a "hands-on" perspective. That is, practical applications with critical evaluations of methodologies and experimental considerations needed to design, execute, and interpret NMR experiments pertinent to biological molecules.

  16. Structural Biology Fact Sheet

    Science.gov (United States)

    ... NIGMS NIGMS Home > Science Education > Structural Biology Structural Biology Tagline (Optional) Middle/Main Content Area PDF Version (688 KB) Other Fact Sheets What is structural biology? Structural biology is the study of how biological ...

  17. Integrating Quantitative Skills in Introductory Ecology: Investigations of Wild Bird Feeding Preferences

    Science.gov (United States)

    Small, Christine J.; Newtoff, Kiersten N.

    2013-01-01

    Undergraduate biology education is undergoing dramatic changes, emphasizing student training in the "tools and practices" of science, particularly quantitative and problem-solving skills. We redesigned a freshman ecology lab to emphasize the importance of scientific inquiry and quantitative reasoning in biology. This multi-week investigation uses…

  18. The rise of quantitative methods in Psychology

    Directory of Open Access Journals (Sweden)

    Denis Cousineau

    2005-09-01

    Full Text Available Quantitative methods have a long history in some scientific fields. Indeed, no one today would consider a qualitative data set in physics or a qualitative theory in chemistry. Quantitative methods are so central in these fields that they are often labelled “hard sciences”. Here, we examine the question whether psychology is ready to enter the “hard science club” like biology did in the forties. The facts that a over half of the statistical techniques used in psychology are less than 40 years old and that b the number of simulations in empirical papers has followed an exponential growth since the eighties, both suggests that the answer is yes. The purpose of Tutorials in Quantitative Methods for Psychology is to provide a concise and easy access to the currents methods.

  19. DNA DAMAGE QUANTITATION BY ALKALINE GEL ELECTROPHORESIS.

    Energy Technology Data Exchange (ETDEWEB)

    SUTHERLAND,B.M.; BENNETT,P.V.; SUTHERLAND, J.C.

    2004-03-24

    Physical and chemical agents in the environment, those used in clinical applications, or encountered during recreational exposures to sunlight, induce damages in DNA. Understanding the biological impact of these agents requires quantitation of the levels of such damages in laboratory test systems as well as in field or clinical samples. Alkaline gel electrophoresis provides a sensitive (down to {approx} a few lesions/5Mb), rapid method of direct quantitation of a wide variety of DNA damages in nanogram quantities of non-radioactive DNAs from laboratory, field, or clinical specimens, including higher plants and animals. This method stems from velocity sedimentation studies of DNA populations, and from the simple methods of agarose gel electrophoresis. Our laboratories have developed quantitative agarose gel methods, analytical descriptions of DNA migration during electrophoresis on agarose gels (1-6), and electronic imaging for accurate determinations of DNA mass (7-9). Although all these components improve sensitivity and throughput of large numbers of samples (7,8,10), a simple version using only standard molecular biology equipment allows routine analysis of DNA damages at moderate frequencies. We present here a description of the methods, as well as a brief description of the underlying principles, required for a simplified approach to quantitation of DNA damages by alkaline gel electrophoresis.

  20. On the limitations of standard statistical modeling in biological systems: a full Bayesian approach for biology.

    Science.gov (United States)

    Gomez-Ramirez, Jaime; Sanz, Ricardo

    2013-09-01

    One of the most important scientific challenges today is the quantitative and predictive understanding of biological function. Classical mathematical and computational approaches have been enormously successful in modeling inert matter, but they may be inadequate to address inherent features of biological systems. We address the conceptual and methodological obstacles that lie in the inverse problem in biological systems modeling. We introduce a full Bayesian approach (FBA), a theoretical framework to study biological function, in which probability distributions are conditional on biophysical information that physically resides in the biological system that is studied by the scientist. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Quantitative high dynamic range beam profiling for fluorescence microscopy

    International Nuclear Information System (INIS)

    Mitchell, T. J.; Saunter, C. D.; O’Nions, W.; Girkin, J. M.; Love, G. D.

    2014-01-01

    Modern developmental biology relies on optically sectioning fluorescence microscope techniques to produce non-destructive in vivo images of developing specimens at high resolution in three dimensions. As optimal performance of these techniques is reliant on the three-dimensional (3D) intensity profile of the illumination employed, the ability to directly record and analyze these profiles is of great use to the fluorescence microscopist or instrument builder. Though excitation beam profiles can be measured indirectly using a sample of fluorescent beads and recording the emission along the microscope detection path, we demonstrate an alternative approach where a miniature camera sensor is used directly within the illumination beam. Measurements taken using our approach are solely concerned with the illumination optics as the detection optics are not involved. We present a miniature beam profiling device and high dynamic range flux reconstruction algorithm that together are capable of accurately reproducing quantitative 3D flux maps over a large focal volume. Performance of this beam profiling system is verified within an optical test bench and demonstrated for fluorescence microscopy by profiling the low NA illumination beam of a single plane illumination microscope. The generality and success of this approach showcases a widely flexible beam amplitude diagnostic tool for use within the life sciences

  2. Biology Branch

    Energy Technology Data Exchange (ETDEWEB)

    Baldwin, W F

    1974-12-31

    Progress is reported on the following studies in biochemistry and molecular biology: study of long pyrimidine polynucleotides in DNA; isolation of thymine dimers from Schizosaccharomyces pombe; thermal stability of high molecular weight RNA; nucleases of Micrococcus radiodurans; effect of ionizing radiation on M. radiodurans cell walls and cell membranes; chemical modification of nucleotides; exonucleases of M. radiodurans; and enzymatic basis of repair of radioinduced damage in M. radiodurans. Genetics, development, and population studies include repair pathways and mutation induction in yeast; induction of pure mutant clones in yeast; radiosensitivity of bacteriophage T4; polyacrylamide gel electrophoresis of bacteriophage T4; radiation genetics of Dahibominus; and radiation studies on bitting flies. (HLW)

  3. Biological biomaterials

    Energy Technology Data Exchange (ETDEWEB)

    Jorge-Herrero, E. [Servicio de Cirugia Experimental. Clinica Puerta de Hierro, Madrid (Spain)

    1997-05-01

    There are a number of situations in which substances of biological origin are employed as biomaterials. Most of them are macromolecules derived from isolated connective tissue or the connective tissue itself in membrane form, in both cases, the tissue can be used in its natural form or be chemically treated. In other cases, certain blood vessels can be chemically pretreated and used as vascular prostheses. Proteins such as albumin, collagen and fibrinogen are employed to coat vascular prostheses. Certain polysaccharides have also been tested for use in controlled drug release systems. Likewise, a number of tissues, such as dura mater, bovine pericardium, procine valves and human valves, are used in the preparation of cardiac prostheses. We also use veins from animals or humans in arterial replacement. In none of these cases are the tissues employed dissimilar to the native tissues as they have been chemically modified, becoming a new bio material with different physical and biochemical properties. In short, we find that natural products are being utilized as biomaterials and must be considered as such; thus, it is necessary to study both their chemicobiological and physicomechanical properties. In the present report, we review the current applications, problems and future prospects of some of these biological biomaterials. (Author) 84 refs.

  4. Quantile-based permutation thresholds for quantitative trait loci hotspots.

    Science.gov (United States)

    Neto, Elias Chaibub; Keller, Mark P; Broman, Andrew F; Attie, Alan D; Jansen, Ritsert C; Broman, Karl W; Yandell, Brian S

    2012-08-01

    Quantitative trait loci (QTL) hotspots (genomic locations affecting many traits) are a common feature in genetical genomics studies and are biologically interesting since they may harbor critical regulators. Therefore, statistical procedures to assess the significance of hotspots are of key importance. One approach, randomly allocating observed QTL across the genomic locations separately by trait, implicitly assumes all traits are uncorrelated. Recently, an empirical test for QTL hotspots was proposed on the basis of the number of traits that exceed a predetermined LOD value, such as the standard permutation LOD threshold. The permutation null distribution of the maximum number of traits across all genomic locations preserves the correlation structure among the phenotypes, avoiding the detection of spurious hotspots due to nongenetic correlation induced by uncontrolled environmental factors and unmeasured variables. However, by considering only the number of traits above a threshold, without accounting for the magnitude of the LOD scores, relevant information is lost. In particular, biologically interesting hotspots composed of a moderate to small number of traits with strong LOD scores may be neglected as nonsignificant. In this article we propose a quantile-based permutation approach that simultaneously accounts for the number and the LOD scores of traits within the hotspots. By considering a sliding scale of mapping thresholds, our method can assess the statistical significance of both small and large hotspots. Although the proposed approach can be applied to any type of heritable high-volume "omic" data set, we restrict our attention to expression (e)QTL analysis. We assess and compare the performances of these three methods in simulations and we illustrate how our approach can effectively assess the significance of moderate and small hotspots with strong LOD scores in a yeast expression data set.

  5. Quantitative uptake of colloidal particles by cell cultures

    Energy Technology Data Exchange (ETDEWEB)

    Feliu, Neus [Department of Physics, Philipps University Marburg, Marburg (Germany); Department for Clinical Science, Intervention and Technology (CLINTEC),Karolinska Institutet, Stockholm (Sweden); Hühn, Jonas; Zyuzin, Mikhail V.; Ashraf, Sumaira; Valdeperez, Daniel; Masood, Atif [Department of Physics, Philipps University Marburg, Marburg (Germany); Said, Alaa Hassan [Department of Physics, Philipps University Marburg, Marburg (Germany); Physics Department, Faculty of Science, South Valley University (Egypt); Escudero, Alberto [Department of Physics, Philipps University Marburg, Marburg (Germany); Instituto de Ciencia de Materiales de Sevilla, CSIC — Universidad de Sevilla, Seville (Spain); Pelaz, Beatriz [Department of Physics, Philipps University Marburg, Marburg (Germany); Gonzalez, Elena [Department of Physics, Philipps University Marburg, Marburg (Germany); University of Vigo, Vigo (Spain); Duarte, Miguel A. Correa [University of Vigo, Vigo (Spain); Roy, Sathi [Department of Physics, Philipps University Marburg, Marburg (Germany); Chakraborty, Indranath [Department of Chemistry, University of Illinois at Urbana Champaign, Urbana, IL (United States); Lim, Mei L.; Sjöqvist, Sebastian [Department for Clinical Science, Intervention and Technology (CLINTEC),Karolinska Institutet, Stockholm (Sweden); Jungebluth, Philipp [Department of Thoracic Surgery, Thoraxklinik, Heidelberg University, Heidelberg (Germany); Parak, Wolfgang J., E-mail: wolfgang.parak@physik.uni-marburg.de [Department of Physics, Philipps University Marburg, Marburg (Germany); CIC biomaGUNE, San Sebastian (Spain)

    2016-10-15

    The use of nanotechnologies involving nano- and microparticles has increased tremendously in the recent past. There are various beneficial characteristics that make particles attractive for a wide range of technologies. However, colloidal particles on the other hand can potentially be harmful for humans and environment. Today, complete understanding of the interaction of colloidal particles with biological systems still remains a challenge. Indeed, their uptake, effects, and final cell cycle including their life span fate and degradation in biological systems are not fully understood. This is mainly due to the complexity of multiple parameters which need to be taken in consideration to perform the nanosafety research. Therefore, we will provide an overview of the common denominators and ideas to achieve universal metrics to assess their safety. The review discusses aspects including how biological media could change the physicochemical properties of colloids, how colloids are endocytosed by cells, how to distinguish between internalized versus membrane-attached colloids, possible correlation of cellular uptake of colloids with their physicochemical properties, and how the colloidal stability of colloids may vary upon cell internalization. In conclusion three main statements are given. First, in typically exposure scenarios only part of the colloids associated with cells are internalized while a significant part remain outside cells attached to their membrane. For quantitative uptake studies false positive counts in the form of only adherent but not internalized colloids have to be avoided. pH sensitive fluorophores attached to the colloids, which can discriminate between acidic endosomal/lysosomal and neutral extracellular environment around colloids offer a possible solution. Second, the metrics selected for uptake studies is of utmost importance. Counting the internalized colloids by number or by volume may lead to significantly different results. Third, colloids

  6. Relative biological effectiveness (RBE) of fission neutrons and gamma rays at occupational exposure levels: Volume 1, Studies on the genetic effects in mice of 60 equal once-weekly exposures to fission neutrons and gamma rays

    International Nuclear Information System (INIS)

    Grahn, D.; Carnes, B.A.

    1987-10-01

    The relative biological effectiveness (RBE) values for low doses of fission neutrons compared to 60 Co gamma rays were determined with four separate assessments of genetic damage induced in young hybrid male mice. Both radiations were delivered at low dose levels over about one-half the adult lifetime as 60 once-weekly exposures. Genetic damage assessed included both transient and residual injury. The latter is more critical, as residual genetic injury can be transmitted to subsequent generations long after the radiation exposures have ceased. Assays were performed periodically during the 60-week exposure period and at 10 or more weeks after the irradiations had terminated. RBE values, with few exceptions, ranged between 5 and 15 for transient injury and between 25 and 50 for different types of residual genetic injury. The most important form of residual genetic damage in this study was the balanced reciprocal chromosome translocation. These translocations continue to be transmitted throughout reproductive life and can lead to reduced fertility and increased prenatal mortality. The best estimate of the RBE value for translocations was 45 +- 10. Implications and recommendations with regard to the neutron quality factor will be presented conjointly with the findings from the data obtained in this same project on life shortening and on the risks of incidence or death from neoplastic disease. 64 refs., 23 tabs

  7. Prognostic, quantitative histopathologic variables in lobular carcinoma of the breast

    DEFF Research Database (Denmark)

    Ladekarl, M; Sørensen, Flemming Brandt

    1993-01-01

    BACKGROUND: A retrospective investigation of 53 consecutively treated patients with operable lobular carcinoma of the breast, with a median follow-up of 6.6 years, was performed to examine the prognostic value of quantitative histopathologic parameters. METHODS: The measurements were performed...... in routinely processed histologic sections using a simple, unbiased technique for the estimation of the three-dimensional mean nuclear volume (vv(nuc)). In addition, quantitative estimates were obtained of the mitotic index (MI), the nuclear index (NI), the nuclear volume fraction (Vv(nuc/tis)), and the mean...... management of patients with breast cancer....

  8. 1st International Congress on Actuarial Science and Quantitative Finance

    CERN Document Server

    Garrido, José; Hernández-Hernández, Daniel; ICASQF

    2015-01-01

    Featuring contributions from industry and academia, this volume includes chapters covering a diverse range of theoretical and empirical aspects of actuarial science and quantitative finance, including portfolio management, derivative valuation, risk theory and the economics of insurance. Developed from the First International Congress on Actuarial Science and Quantitative Finance, held at the Universidad Nacional de Colombia in Bogotá in June 2014, this volume highlights different approaches to issues arising from industries in the Andean and Carribean regions. Contributions address topics such as Reverse mortgage schemes and urban dynamics, modeling spot price dynamics in the electricity market, and optimizing calibration and pricing with SABR models.

  9. Biological effects

    International Nuclear Information System (INIS)

    Trott, K.R.

    1973-01-01

    Following an introduction into the field of cellular radiation effect considering the most important experimental results, the biological significance of the colony formation ability is brought out. The inactivation concept of stem cells does not only prove to be good, according to the present results, in the interpretation of the pathogenesis of acute radiation effects on moult tissue, it also enables chronicle radiation injuries to be interpreted through changes in the fibrous part of the organs. Radiation therapy of tumours can also be explained to a large extent by the radiation effect on the unlimited reproductiveness of tumour cells. The more or less similar dose effect curves for healthy and tumour tissue in practice lead to intermittent irradiation. The dependence of the intermittent doses and intervals on factors such as Elkind recovery, synchronisation, redistribution, reoxygenation, repopulation and regeneration are reviewed. (ORU/LH) [de

  10. Quantitative Decision Support Requires Quantitative User Guidance

    Science.gov (United States)

    Smith, L. A.

    2009-12-01

    Is it conceivable that models run on 2007 computer hardware could provide robust and credible probabilistic information for decision support and user guidance at the ZIP code level for sub-daily meteorological events in 2060? In 2090? Retrospectively, how informative would output from today’s models have proven in 2003? or the 1930’s? Consultancies in the United Kingdom, including the Met Office, are offering services to “future-proof” their customers from climate change. How is a US or European based user or policy maker to determine the extent to which exciting new Bayesian methods are relevant here? or when a commercial supplier is vastly overselling the insights of today’s climate science? How are policy makers and academic economists to make the closely related decisions facing them? How can we communicate deep uncertainty in the future at small length-scales without undermining the firm foundation established by climate science regarding global trends? Three distinct aspects of the communication of the uses of climate model output targeting users and policy makers, as well as other specialist adaptation scientists, are discussed. First, a brief scientific evaluation of the length and time scales at which climate model output is likely to become uninformative is provided, including a note on the applicability the latest Bayesian methodology to current state-of-the-art general circulation models output. Second, a critical evaluation of the language often employed in communication of climate model output, a language which accurately states that models are “better”, have “improved” and now “include” and “simulate” relevant meteorological processed, without clearly identifying where the current information is thought to be uninformative and misleads, both for the current climate and as a function of the state of the (each) climate simulation. And thirdly, a general approach for evaluating the relevance of quantitative climate model output

  11. Creating biological nanomaterials using synthetic biology

    International Nuclear Information System (INIS)

    Rice, MaryJoe K; Ruder, Warren C

    2014-01-01

    Synthetic biology is a new discipline that combines science and engineering approaches to precisely control biological networks. These signaling networks are especially important in fields such as biomedicine and biochemical engineering. Additionally, biological networks can also be critical to the production of naturally occurring biological nanomaterials, and as a result, synthetic biology holds tremendous potential in creating new materials. This review introduces the field of synthetic biology, discusses how biological systems naturally produce materials, and then presents examples and strategies for incorporating synthetic biology approaches in the development of new materials. In particular, strategies for using synthetic biology to produce both organic and inorganic nanomaterials are discussed. Ultimately, synthetic biology holds the potential to dramatically impact biological materials science with significant potential applications in medical systems. (review)

  12. Creating biological nanomaterials using synthetic biology.

    Science.gov (United States)

    Rice, MaryJoe K; Ruder, Warren C

    2014-02-01

    Synthetic biology is a new discipline that combines science and engineering approaches to precisely control biological networks. These signaling networks are especially important in fields such as biomedicine and biochemical engineering. Additionally, biological networks can also be critical to the production of naturally occurring biological nanomaterials, and as a result, synthetic biology holds tremendous potential in creating new materials. This review introduces the field of synthetic biology, discusses how biological systems naturally produce materials, and then presents examples and strategies for incorporating synthetic biology approaches in the development of new materials. In particular, strategies for using synthetic biology to produce both organic and inorganic nanomaterials are discussed. Ultimately, synthetic biology holds the potential to dramatically impact biological materials science with significant potential applications in medical systems.

  13. Analysis of arsenical metabolites in biological samples.

    Science.gov (United States)

    Hernandez-Zavala, Araceli; Drobna, Zuzana; Styblo, Miroslav; Thomas, David J

    2009-11-01

    Quantitation of iAs and its methylated metabolites in biological samples provides dosimetric information needed to understand dose-response relations. Here, methods are described for separation of inorganic and mono-, di-, and trimethylated arsenicals by thin layer chromatography. This method has been extensively used to track the metabolism of the radionuclide [(73)As] in a variety of in vitro assay systems. In addition, a hydride generation-cryotrapping-gas chromatography-atomic absorption spectrometric method is described for the quantitation of arsenicals in biological samples. This method uses pH-selective hydride generation to differentiate among arsenicals containing trivalent or pentavalent arsenic.

  14. Biological Remediation of Petroleum Contaminants

    Science.gov (United States)

    Kuhad, Ramesh Chander; Gupta, Rishi

    Large volumes of hazardous wastes are generated in the form of oily sludges and contaminated soils during crude oil transportation and processing. Although many physical, chemical and biological treatment technologies are available for petroleum contaminants petroleum contaminants in soil, biological methods have been considered the most cost-effective. Practical biological remediation methods typically involve direct use of the microbes naturally occurring in the contaminated environment and/or cultured indigenous or modified microorganisms. Environmental and nutritional factors, including the properties of the soil, the chemical structure of the hydrocarbon(s), oxygen, water, nutrient availability, pH, temperature, and contaminant bioavailability, can significantly affect the rate and the extent of hydrocarbon biodegradation hydrocarbon biodegradation by microorganisms in contaminated soils. This chapter concisely discusses the major aspects of bioremediation of petroleum contaminants.

  15. Extending Quantitative Easing

    DEFF Research Database (Denmark)

    Hallett, Andrew Hughes; Fiedler, Salomon; Kooths, Stefan

    The notes in this compilation address the pros and cons associated with the extension of ECB quantitative easing programme of asset purchases. The notes have been requested by the Committee on Economic and Monetary Affairs as an input for the February 2017 session of the Monetary Dialogue....

  16. Quantitative Moessbauer analysis

    International Nuclear Information System (INIS)

    Collins, R.L.

    1978-01-01

    The quantitative analysis of Moessbauer data, as in the measurement of Fe 3+ /Fe 2+ concentration, has not been possible because of the different mean square velocities (x 2 ) of Moessbauer nuclei at chemically different sites. A method is now described which, based on Moessbauer data at several temperatures, permits the comparison of absorption areas at (x 2 )=0. (Auth.)

  17. Women are underrepresented in computational biology: An analysis of the scholarly literature in biology, computer science and computational biology.

    Science.gov (United States)

    Bonham, Kevin S; Stefan, Melanie I

    2017-10-01

    While women are generally underrepresented in STEM fields, there are noticeable differences between fields. For instance, the gender ratio in biology is more balanced than in computer science. We were interested in how this difference is reflected in the interdisciplinary field of computational/quantitative biology. To this end, we examined the proportion of female authors in publications from the PubMed and arXiv databases. There are fewer female authors on research papers in computational biology, as compared to biology in general. This is true across authorship position, year, and journal impact factor. A comparison with arXiv shows that quantitative biology papers have a higher ratio of female authors than computer science papers, placing computational biology in between its two parent fields in terms of gender representation. Both in biology and in computational biology, a female last author increases the probability of other authors on the paper being female, pointing to a potential role of female PIs in influencing the gender balance.

  18. Women are underrepresented in computational biology: An analysis of the scholarly literature in biology, computer science and computational biology.

    Directory of Open Access Journals (Sweden)

    Kevin S Bonham

    2017-10-01

    Full Text Available While women are generally underrepresented in STEM fields, there are noticeable differences between fields. For instance, the gender ratio in biology is more balanced than in computer science. We were interested in how this difference is reflected in the interdisciplinary field of computational/quantitative biology. To this end, we examined the proportion of female authors in publications from the PubMed and arXiv databases. There are fewer female authors on research papers in computational biology, as compared to biology in general. This is true across authorship position, year, and journal impact factor. A comparison with arXiv shows that quantitative biology papers have a higher ratio of female authors than computer science papers, placing computational biology in between its two parent fields in terms of gender representation. Both in biology and in computational biology, a female last author increases the probability of other authors on the paper being female, pointing to a potential role of female PIs in influencing the gender balance.

  19. Oscillations in Mathematical Biology

    CERN Document Server

    1983-01-01

    The papers in this volume are based on talks given at a one day conference held on the campus of Adelphi University in April 1982. The conference was organized with the title "Oscillations in Mathematical Biology;" however the speakers were allowed considerable latitutde in their choice of topics. In the event, the talks all concerned the dynamics of non-linear systems arising in biology so that the conference achieved a good measure of cohesion. Some of the speakers cho~e not to submit a manuscript for these proceedings, feeling that their material was too conjectural to be committed to print. Also the paper of Rinzel and Troy is a distillation of the two separate talks that the authors gave. Otherwise the material reproduces the conference proceedings. The conference was made possible by the generous support of the Office of the Dean of the College of Arts and Sciences at Adelphi. The bulk of the organization of the conference was carried out by Dr. Ronald Grisell whose energy was in large measure responsib...

  20. Critical Quantitative Inquiry in Context

    Science.gov (United States)

    Stage, Frances K.; Wells, Ryan S.

    2014-01-01

    This chapter briefly traces the development of the concept of critical quantitative inquiry, provides an expanded conceptualization of the tasks of critical quantitative research, offers theoretical explanation and justification for critical research using quantitative methods, and previews the work of quantitative criticalists presented in this…

  1. A Brief Introduction to Chinese Biological Biological

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Chinese Biological Abstracts sponsored by the Library, the Shanghai Institutes for Biological Sciences, the Biological Documentation and Information Network, all of the Chinese Academy of Sciences, commenced publication in 1987 and was initiated to provide access to the Chinese information in the field of biology.

  2. Practical quantitative measures of ALARA

    International Nuclear Information System (INIS)

    Kathren, R.L.; Larson, H.V.

    1982-06-01

    Twenty specific quantitative measures to assist in evaluating the effectiveness of as low as reasonably achievable (ALARA) programs are described along with their applicability, practicality, advantages, disadvantages, and potential for misinterpretation or dortion. Although no single index or combination of indices is suitable for all facilities, generally, these five: (1) mean individual dose equivalent (MIDE) to the total body from penetrating radiations; (2) statistical distribution of MIDE to the whole body from penetrating radiations; (3) cumulative penetrating whole body dose equivalent; (4) MIDE evaluated by job classification; and (5) MIDE evaluated by work location-apply to most programs. Evaluation of other programs may require other specific dose equivalent based indices, including extremity exposure data, cumulative dose equivalent to organs or to the general population, and nonpenetrating radiation dose equivalents. Certain nondose equivalent indices, such as the size of the radiation or contamination area, may also be used; an airborne activity index based on air concentration, room volume, and radiotoxicity is developed for application in some ALARA programs

  3. Parameter determination for quantitative PIXE analysis using genetic algorithms

    International Nuclear Information System (INIS)

    Aspiazu, J.; Belmont-Moreno, E.

    1996-01-01

    For biological and environmental samples, PIXE technique is in particular advantage for elemental analysis, but the quantitative analysis implies accomplishing complex calculations that require the knowledge of more than a dozen parameters. Using a genetic algorithm, the authors give here an account of the procedure to obtain the best values for the parameters necessary to fit the efficiency for a X-ray detector. The values for some variables involved in quantitative PIXE analysis, were manipulated in a similar way as the genetic information is treated in a biological process. The authors carried out the algorithm until they reproduce, within the confidence interval, the elemental concentrations corresponding to a reference material

  4. Expermental Studies of quantitative evaluation using HPLC

    Directory of Open Access Journals (Sweden)

    Ki Rok Kwon

    2005-06-01

    Full Text Available Methods : This study was conducted to carry out quantitative evaluation using HPLC Content analysis was done using HPLC Results : According to HPLC analysis, each BVA-1 contained approximately 0.36㎍ melittin, and BVA-2 contained approximately 0.54㎍ melittin. But the volume of coating was so minute, slight difference exists between each needle. Conclusion : Above results indicate that the bee venom acupuncture can complement shortcomings of syringe usage as a part of Oriental medicine treatment, but extensive researches should be done for further verification.

  5. Quantitative skeletal scintiscanning

    International Nuclear Information System (INIS)

    Haushofer, R.

    1982-01-01

    330 patients were examined by skeletal scintiscanning with sup(99m)Tc pyrophosphate and sup(99m)methylene diphosphonate in the years between 1977 and 1979. Course control examinations were carried out in 12 patients. The collective of patients presented with primary skeletal tumours, metastases, inflammatory and degenerative skeletal diseases. Bone scintiscanning combined with the ''region of interest'' technique was found to be an objective and reproducible technique for quantitative measurement of skeletal radioactivity concentrations. The validity of nuclear skeletal examinations can thus be enhanced as far as diagnosis, course control, and differential diagnosis are concerned. Quantitative skeletal scintiscanning by means of the ''region of interest'' technique has opened up a new era in skeletal diagnosis by nuclear methods. (orig./MG) [de

  6. Quantitative maps of groundwater resources in Africa

    International Nuclear Information System (INIS)

    MacDonald, A M; Bonsor, H C; Dochartaigh, B É Ó; Taylor, R G

    2012-01-01

    In Africa, groundwater is the major source of drinking water and its use for irrigation is forecast to increase substantially to combat growing food insecurity. Despite this, there is little quantitative information on groundwater resources in Africa, and groundwater storage is consequently omitted from assessments of freshwater availability. Here we present the first quantitative continent-wide maps of aquifer storage and potential borehole yields in Africa based on an extensive review of available maps, publications and data. We estimate total groundwater storage in Africa to be 0.66 million km 3 (0.36–1.75 million km 3 ). Not all of this groundwater storage is available for abstraction, but the estimated volume is more than 100 times estimates of annual renewable freshwater resources on Africa. Groundwater resources are unevenly distributed: the largest groundwater volumes are found in the large sedimentary aquifers in the North African countries Libya, Algeria, Egypt and Sudan. Nevertheless, for many African countries appropriately sited and constructed boreholes can support handpump abstraction (yields of 0.1–0.3 l s −1 ), and contain sufficient storage to sustain abstraction through inter-annual variations in recharge. The maps show further that the potential for higher yielding boreholes ( > 5 l s −1 ) is much more limited. Therefore, strategies for increasing irrigation or supplying water to rapidly urbanizing cities that are predicated on the widespread drilling of high yielding boreholes are likely to be unsuccessful. As groundwater is the largest and most widely distributed store of freshwater in Africa, the quantitative maps are intended to lead to more realistic assessments of water security and water stress, and to promote a more quantitative approach to mapping of groundwater resources at national and regional level. (letter)

  7. Quantitative FDG in depression

    Energy Technology Data Exchange (ETDEWEB)

    Chua, P.; O`Keefe, G.J.; Egan, G.F.; Berlangieri, S.U.; Tochon-Danguy, H.J.; Mckay, W.J.; Morris, P.L.P.; Burrows, G.D. [Austin Hospital, Melbourne, VIC (Australia). Dept of Psychiatry and Centre for PET

    1998-03-01

    Full text: Studies of regional cerebral glucose metabolism (rCMRGlu) using positron emission tomography (PET) in patients with affective disorders have consistently demonstrated reduced metabolism in the frontal regions. Different quantitative and semi-quantitative rCMRGlu regions of interest (ROI) comparisons, e.g. absolute metabolic rates, ratios of dorsolateral prefrontal cortex (DLPFC) to ipsilateral hemisphere cortex, have been reported. These studies suffered from the use of a standard brain atlas to define ROls, whereas in this case study, the individual``s magnetic resonance imaging (MRI) scan was registered with the PET scan to enable accurate neuroanatomical ROI definition for the subject. The patient is a 36-year-old female with a six-week history of major depression (HAM-D = 34, MMSE = 28). A quantitative FDG PET study and an MRI scan were performed. Six MRI-guided ROls (DLPFC, PFC, whole hemisphere) were defined. The average rCMRGlu in the DLPFC (left = 28.8 + 5.8 mol/100g/min; right = 25.6 7.0 mol/100g/min) were slightly reduced compared to the ipsilateral hemispherical rate (left = 30.4 6.8 mol/100g/min; right = 29.5 7.2 mol/100g/min). The ratios of DLPFC to ipsilateral hemispheric rate were close to unity (left = 0.95 0.29; right 0.87 0.32). The right to left DLPFC ratio did not show any significant asymmetry (0.91 0.30). These results do not correlate with earlier published results reporting decreased left DLPFC rates compared to right DLPFC, although our results will need to be replicated with a group of depressed patients. Registration of PET and MRI studies is necessary in ROI-based quantitative FDG PET studies to allow for the normal anatomical variation among individuals, and thus is essential for accurate comparison of rCMRGlu between individuals.

  8. Quantitative FDG in depression

    International Nuclear Information System (INIS)

    Chua, P.; O'Keefe, G.J.; Egan, G.F.; Berlangieri, S.U.; Tochon-Danguy, H.J.; Mckay, W.J.; Morris, P.L.P.; Burrows, G.D.

    1998-01-01

    Full text: Studies of regional cerebral glucose metabolism (rCMRGlu) using positron emission tomography (PET) in patients with affective disorders have consistently demonstrated reduced metabolism in the frontal regions. Different quantitative and semi-quantitative rCMRGlu regions of interest (ROI) comparisons, e.g. absolute metabolic rates, ratios of dorsolateral prefrontal cortex (DLPFC) to ipsilateral hemisphere cortex, have been reported. These studies suffered from the use of a standard brain atlas to define ROls, whereas in this case study, the individual''s magnetic resonance imaging (MRI) scan was registered with the PET scan to enable accurate neuroanatomical ROI definition for the subject. The patient is a 36-year-old female with a six-week history of major depression (HAM-D = 34, MMSE = 28). A quantitative FDG PET study and an MRI scan were performed. Six MRI-guided ROls (DLPFC, PFC, whole hemisphere) were defined. The average rCMRGlu in the DLPFC (left = 28.8 + 5.8 mol/100g/min; right = 25.6 7.0 mol/100g/min) were slightly reduced compared to the ipsilateral hemispherical rate (left = 30.4 6.8 mol/100g/min; right = 29.5 7.2 mol/100g/min). The ratios of DLPFC to ipsilateral hemispheric rate were close to unity (left = 0.95 0.29; right 0.87 0.32). The right to left DLPFC ratio did not show any significant asymmetry (0.91 0.30). These results do not correlate with earlier published results reporting decreased left DLPFC rates compared to right DLPFC, although our results will need to be replicated with a group of depressed patients. Registration of PET and MRI studies is necessary in ROI-based quantitative FDG PET studies to allow for the normal anatomical variation among individuals, and thus is essential for accurate comparison of rCMRGlu between individuals

  9. Quantitative traits and diversification.

    Science.gov (United States)

    FitzJohn, Richard G

    2010-12-01

    Quantitative traits have long been hypothesized to affect speciation and extinction rates. For example, smaller body size or increased specialization may be associated with increased rates of diversification. Here, I present a phylogenetic likelihood-based method (quantitative state speciation and extinction [QuaSSE]) that can be used to test such hypotheses using extant character distributions. This approach assumes that diversification follows a birth-death process where speciation and extinction rates may vary with one or more traits that evolve under a diffusion model. Speciation and extinction rates may be arbitrary functions of the character state, allowing much flexibility in testing models of trait-dependent diversification. I test the approach using simulated phylogenies and show that a known relationship between speciation and a quantitative character could be recovered in up to 80% of the cases on large trees (500 species). Consistent with other approaches, detecting shifts in diversification due to differences in extinction rates was harder than when due to differences in speciation rates. Finally, I demonstrate the application of QuaSSE to investigate the correlation between body size and diversification in primates, concluding that clade-specific differences in diversification may be more important than size-dependent diversification in shaping the patterns of diversity within this group.

  10. Individual patient dosimetry using quantitative SPECT imaging

    International Nuclear Information System (INIS)

    Gonzalez, J.; Oliva, J.; Baum, R.; Fisher, S.

    2002-01-01

    An approach is described to provide individual patient dosimetry for routine clinical use. Accurate quantitative SPECT imaging was achieved using appropriate methods. The volume of interest (VOI) was defined semi-automatically using a fixed threshold value obtained from phantom studies. The calibration factor to convert the voxel counts from SPECT images into activity values was determine from calibrated point source using the same threshold value as in phantom studies. From selected radionuclide the dose within and outside a sphere of voxel dimension at different distances was computed through dose point-kernels to obtain a discrete absorbed dose kernel representation around the volume source with uniform activity distribution. The spatial activity distribution from SPECT imaging was convolved with this kernel representation using the discrete Fourier transform method to yield three-dimensional absorbed dose rate distribution. The accuracy of dose rates calculation was validated by software phantoms. The absorbed dose was determined by integration of the dose rate distribution for each volume of interest (VOI). Parameters for treatment optimization such as dose rate volume histograms and dose rate statistic are provided. A patient example was used to illustrate our dosimetric calculations

  11. Evaluation of conformal radiotherapy techniques through physics and biologic criteria

    International Nuclear Information System (INIS)

    Bloch, Jonatas Carrero

    2012-01-01

    In the fight against cancer, different irradiation techniques have been developed based on technological advances and aiming to optimize the elimination of tumor cells with the lowest damage to healthy tissues. The radiotherapy planning goal is to establish irradiation technical parameters in order to achieve the prescribed dose distribution over the treatment volumes. While dose prescription is based on radiosensitivity of the irradiated tissues, the physical calculations on treatment planning take into account dosimetric parameters related to the radiation beam and the physical characteristics of the irradiated tissues. To incorporate tissue's radiosensitivity into radiotherapy planning calculations can help particularize treatments and establish criteria to compare and elect radiation techniques, contributing to the tumor control and the success of the treatment. Accordingly, biological models of cellular response to radiation have to be well established. This work aimed to study the applicability of using biological models in radiotherapy planning calculations to aid evaluating radiotherapy techniques. Tumor control probability (TCP) was studied for two formulations of the linear-quadratic model, with and without repopulation, as a function of planning parameters, as dose per fraction, and of radiobiological parameters, as the α/β ratio. Besides, the usage of biological criteria to compare radiotherapy techniques was tested using a prostate planning simulated with Monte Carlo code PENELOPE. Afterwards, prostate planning for five patients from the Hospital das Clinicas da Faculdade de Medicina de Ribeirao Preto, USP, using three different techniques were compared using the tumor control probability. In that order, dose matrices from the XiO treatment planning system were converted to TCP distributions and TCP-volume histograms. The studies performed allow the conclusions that radiobiological parameters can significantly influence tumor control

  12. Quantitative radionuclide angiocardiography

    International Nuclear Information System (INIS)

    Scholz, P.M.; Rerych, S.K.; Moran, J.F.; Newman, G.E.; Douglas, J.M.; Sabiston, D.C. Jr.; Jones, R.H.

    1980-01-01

    This study introduces a new method for calculating actual left ventricular volumes and cardiac output from data recorded during a single transit of a radionuclide bolus through the heart, and describes in detail current radionuclide angiocardiography methodology. A group of 64 healthy adults with a wide age range were studied to define the normal range of hemodynamic parameters determined by the technique. Radionuclide angiocardiograms were performed in patients undergoing cardiac catherization to validate the measurements. In 33 patients studied by both techniques on the same day, a close correlation was documented for measurement of ejection fraction and end-diastolic volume. To validate the method of volumetric cardiac output calcuation, 33 simultaneous radionuclide and indocyanine green dye determinations of cardiac output were performed in 18 normal young adults. These independent comparisons of radionuclide measurements with two separate methods document that initial transit radionuclide angiocardiography accurately assesses left ventricular function

  13. Quantitative description of woody plant communities: Part II ...

    African Journals Online (AJOL)

    These procedures are divided into primary and secondary calculations. The former is then divided into the calculation of spatial tree volume and preliminary calculations regarding the complete quantitative description. The latter include the calculation of the evapotranspiration tree equivalent (ETTE), browse tree equivalent ...

  14. Determination of pulmonary volume by CT

    International Nuclear Information System (INIS)

    Kakinuma, Ryutaro

    1984-01-01

    The pulmonary volume overlapping the shadows of the mediastinum and the hilus pulmonis in frontal chest films was determined by means of CT. The pulmonary volume, between the levels of the aortic arch and just above the right diaphragm, overlapping the shadows of the mediastinum and the hilus, was one fourth of the entire pulmonary volume between the same levels. When the lungs overlapping the mediastinum and the hilus were divided into a region overlapping the spine and the aorta (region A) and another region (region B), the ratio of the volume of region A to that of region B was 1:3. CT is useful for quantitative roentgenological anatomy of the lungs. (author)

  15. Quantitative phosphoproteomics to characterize signaling networks

    DEFF Research Database (Denmark)

    Rigbolt, Kristoffer T G; Blagoev, Blagoy

    2012-01-01

    for analyzing protein phosphorylation at a system-wide scale and has become the intuitive strategy for comprehensive characterization of signaling networks. Contemporary phosphoproteomics use highly optimized procedures for sample preparation, mass spectrometry and data analysis algorithms to identify......Reversible protein phosphorylation is involved in the regulation of most, if not all, major cellular processes via dynamic signal transduction pathways. During the last decade quantitative phosphoproteomics have evolved from a highly specialized area to a powerful and versatile platform...... and quantify thousands of phosphorylations, thus providing extensive overviews of the cellular signaling networks. As a result of these developments quantitative phosphoproteomics have been applied to study processes as diverse as immunology, stem cell biology and DNA damage. Here we review the developments...

  16. Quantitative risk in radiation protection standards

    International Nuclear Information System (INIS)

    Bond, V.P.

    1979-01-01

    Although the overall aim of radiobiology is to understand the biological effects of radiation, it also has the implied practical purpose of developing rational measures for the control of radiation exposure in man. The emphasis in this presentation is to show that the enormous effort expended over the years to develop quantitative dose-effect relationships in biochemical and cellular systems, animals, and human beings now seems to be paying off. The pieces appear to be falling into place, and a framework is evolving to utilize these data. Specifically, quantitative risk assessments will be discussed in terms of the cellular, animal, and human data on which they are based; their use in the development of radiation protection standards; and their present and potential impact and meaning in relation to the quantity dose equivalent and its special unit, the rem

  17. Some nonlinear challenges in biology

    International Nuclear Information System (INIS)

    Mosconi, Francesco; Julou, Thomas; Desprat, Nicolas; Sinha, Deepak Kumar; Allemand, Jean-François; Croquette, Vincent; Bensimon, David

    2008-01-01

    Driven by a deluge of data, biology is undergoing a transition to a more quantitative science. Making sense of the data, building new models, asking the right questions and designing smart experiments to answer them are becoming ever more relevant. In this endeavour, nonlinear approaches can play a fundamental role. The biochemical reactions that underlie life are very often nonlinear. The functional features exhibited by biological systems at all levels (from the activity of an enzyme to the organization of a colony of ants, via the development of an organism or a functional module like the one responsible for chemotaxis in bacteria) are dynamically robust. They are often unaffected by order of magnitude variations in the dynamical parameters, in the number or concentrations of actors (molecules, cells, organisms) or external inputs (food, temperature, pH, etc). This type of structural robustness is also a common feature of nonlinear systems, exemplified by the fundamental role played by dynamical fixed points and attractors and by the use of generic equations (logistic map, Fisher–Kolmogorov equation, the Stefan problem, etc.) in the study of a plethora of nonlinear phenomena. However, biological systems differ from these examples in two important ways: the intrinsic stochasticity arising from the often very small number of actors and the role played by evolution. On an evolutionary time scale, nothing in biology is frozen. The systems observed today have evolved from solutions adopted in the past and they will have to adapt in response to future conditions. The evolvability of biological system uniquely characterizes them and is central to biology. As the great biologist T Dobzhansky once wrote: 'nothing in biology makes sense except in the light of evolution'. (open problem)

  18. Space Synthetic Biology Project

    Science.gov (United States)

    Howard, David; Roman, Monsi; Mansell, James (Matt)

    2015-01-01

    Synthetic biology is an effort to make genetic engineering more useful by standardizing sections of genetic code. By standardizing genetic components, biological engineering will become much more similar to traditional fields of engineering, in which well-defined components and subsystems are readily available in markets. Specifications of the behavior of those components and subsystems can be used to model a system which incorporates them. Then, the behavior of the novel system can be simulated and optimized. Finally, the components and subsystems can be purchased and assembled to create the optimized system, which most often will exhibit behavior similar to that indicated by the model. The Space Synthetic Biology project began in 2012 as a multi-Center effort. The purpose of this project was to harness Synthetic Biology principals to enable NASA's missions. A central target for application was to Environmental Control & Life Support (ECLS). Engineers from NASA Marshall Space Flight Center's (MSFC's) ECLS Systems Development Branch (ES62) were brought into the project to contribute expertise in operational ECLS systems. Project lead scientists chose to pursue the development of bioelectrochemical technologies to spacecraft life support. Therefore, the ECLS element of the project became essentially an effort to develop a bioelectrochemical ECLS subsystem. Bioelectrochemical systems exploit the ability of many microorganisms to drive their metabolisms by direct or indirect utilization of electrical potential gradients. Whereas many microorganisms are capable of deriving the energy required for the processes of interest (such as carbon dioxide (CO2) fixation) from sunlight, it is believed that subsystems utilizing electrotrophs will exhibit smaller mass, volume, and power requirements than those that derive their energy from sunlight. In the first 2 years of the project, MSFC personnel conducted modeling, simulation, and conceptual design efforts to assist the

  19. Quantitative power Doppler ultrasound measures of peripheral joint synovitis in poor prognosis early rheumatoid arthritis predict radiographic progression.

    Science.gov (United States)

    Sreerangaiah, Dee; Grayer, Michael; Fisher, Benjamin A; Ho, Meilien; Abraham, Sonya; Taylor, Peter C

    2016-01-01

    To assess the value of quantitative vascular imaging by power Doppler US (PDUS) as a tool that can be used to stratify patient risk of joint damage in early seropositive RA while still biologic naive but on synthetic DMARD treatment. Eighty-five patients with seropositive RA of power Doppler volume and 2D vascularity scores were the most useful US predictors of deterioration. These variables were modelled in two equations that estimate structural damage over 12 months. The equations had a sensitivity of 63.2% and specificity of 80.9% for predicting radiographic structural damage and a sensitivity of 54.2% and specificity of 96.7% for predicting structural damage on ultrasonography. In seropositive early RA, quantitative vascular imaging by PDUS has clinical utility in predicting which patients will derive benefit from early use of biologic therapy. © The Author 2015. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. Amino acid analysis in biological fluids by GC-MS

    OpenAIRE

    Kaspar, Hannelore

    2009-01-01

    Amino acids are intermediates in cellular metabolism and their quantitative analysis plays an important role in disease diagnostics. A gas chromatography-mass spectrometry (GC-MS) based method was developed for the quantitative analysis of free amino acids as their propyl chloroformate derivatives in biological fluids. Derivatization with propyl chloroformate could be carried out directly in the biological samples without prior protein precipitation or solid-phase extraction of the amino acid...

  1. Modification-specific proteomics in plant biology

    DEFF Research Database (Denmark)

    Ytterberg, A Jimmy; Jensen, Ole N

    2010-01-01

    and proteomics. In general, methods for PTM characterization are developed to study yeast and mammalian biology and later adopted to investigate plants. Our point of view is that it is advantageous to enrich for PTMs on the peptide level as part of a quantitative proteomics strategy to not only identify the PTM...

  2. Noninvasive Quantitative Imaging of Collagen Microstructure in Three-Dimensional Hydrogels Using High-Frequency Ultrasound.

    Science.gov (United States)

    Mercado, Karla P; Helguera, María; Hocking, Denise C; Dalecki, Diane

    2015-07-01

    Collagen I is widely used as a natural component of biomaterials for both tissue engineering and regenerative medicine applications. The physical and biological properties of fibrillar collagens are strongly tied to variations in collagen fiber microstructure. The goal of this study was to develop the use of high-frequency quantitative ultrasound to assess collagen microstructure within three-dimensional (3D) hydrogels noninvasively and nondestructively. The integrated backscatter coefficient (IBC) was employed as a quantitative ultrasound parameter to detect, image, and quantify spatial variations in collagen fiber density and diameter. Collagen fiber microstructure was varied by fabricating hydrogels with different collagen concentrations or polymerization temperatures. IBC values were computed from measurements of the backscattered radio-frequency ultrasound signals collected using a single-element transducer (38-MHz center frequency, 13-47 MHz bandwidth). The IBC increased linearly with increasing collagen concentration and decreasing polymerization temperature. Parametric 3D images of the IBC were generated to visualize and quantify regional variations in collagen microstructure throughout the volume of hydrogels fabricated in standard tissue culture plates. IBC parametric images of corresponding cell-embedded collagen gels showed cell accumulation within regions having elevated collagen IBC values. The capability of this ultrasound technique to noninvasively detect and quantify spatial differences in collagen microstructure offers a valuable tool to monitor the structural properties of collagen scaffolds during fabrication, to detect functional differences in collagen microstructure, and to guide fundamental research on the interactions of cells and collagen matrices.

  3. Quantitative ion implantation

    International Nuclear Information System (INIS)

    Gries, W.H.

    1976-06-01

    This is a report of the study of the implantation of heavy ions at medium keV-energies into electrically conducting mono-elemental solids, at ion doses too small to cause significant loss of the implanted ions by resputtering. The study has been undertaken to investigate the possibility of accurate portioning of matter in submicrogram quantities, with some specific applications in mind. The problem is extensively investigated both on a theoretical level and in practice. A mathematical model is developed for calculating the loss of implanted ions by resputtering as a function of the implanted ion dose and the sputtering yield. Numerical data are produced therefrom which permit a good order-of-magnitude estimate of the loss for any ion/solid combination in which the ions are heavier than the solid atoms, and for any ion energy from 10 to 300 keV. The implanted ion dose is measured by integration of the ion beam current, and equipment and techniques are described which make possible the accurate integration of an ion current in an electromagnetic isotope separator. The methods are applied to two sample cases, one being a stable isotope, the other a radioisotope. In both cases independent methods are used to show that the implantation is indeed quantitative, as predicted. At the same time the sample cases are used to demonstrate two possible applications for quantitative ion implantation, viz. firstly for the manufacture of calibration standards for instrumental micromethods of elemental trace analysis in metals, and secondly for the determination of the half-lives of long-lived radioisotopes by a specific activity method. It is concluded that the present study has advanced quantitative ion implantation to the state where it can be successfully applied to the solution of problems in other fields

  4. US and Russian Cooperation in Space Biology and Medicine

    Science.gov (United States)

    Sawin, C.F.; Hanson, S.I.; House, N.G.; Pestov, I.D.

    2009-01-01

    This slide presentation concerns the 5th volume of a joint publication that describes the cooperation between the United States and Russia in research into space biology and medicine. Each of the chapters is briefly summarized.

  5. Physics with illustrative examples from medicine and biology

    CERN Document Server

    Benedek, George B

    Physics: with illustrative examples from medicine and biology is a three-volume set of textbooks in introductory physics written at the calculus level and designed primarily for students with career objectives in the life sciences.

  6. Biometry: the principles and practice of statistics in biological research

    National Research Council Canada - National Science Library

    Sokal, R.R; Rohlf, F.J

    1969-01-01

    In this introductory textbook, with its companion volume of tables, the authors provide a balanced presentation of statistical methodology for the descriptive, experimental, and analytical study of biological phenomena...

  7. F# for quantitative finance

    CERN Document Server

    Astborg, Johan

    2013-01-01

    To develop your confidence in F#, this tutorial will first introduce you to simpler tasks such as curve fitting. You will then advance to more complex tasks such as implementing algorithms for trading semi-automation in a practical scenario-based format.If you are a data analyst or a practitioner in quantitative finance, economics, or mathematics and wish to learn how to use F# as a functional programming language, this book is for you. You should have a basic conceptual understanding of financial concepts and models. Elementary knowledge of the .NET framework would also be helpful.

  8. Biological effects of radiation

    International Nuclear Information System (INIS)

    2013-01-01

    This fourth chapter presents: cell structure and metabolism; radiation interaction with biological tissues; steps of the production of biological effect of radiation; radiosensitivity of tissues; classification of biological effects; reversibility, transmissivity and influence factors; pre-natal biological effects; biological effects in therapy and syndrome of acute irradiation

  9. Mammalian synthetic biology for studying the cell.

    Science.gov (United States)

    Mathur, Melina; Xiang, Joy S; Smolke, Christina D

    2017-01-02

    Synthetic biology is advancing the design of genetic devices that enable the study of cellular and molecular biology in mammalian cells. These genetic devices use diverse regulatory mechanisms to both examine cellular processes and achieve precise and dynamic control of cellular phenotype. Synthetic biology tools provide novel functionality to complement the examination of natural cell systems, including engineered molecules with specific activities and model systems that mimic complex regulatory processes. Continued development of quantitative standards and computational tools will expand capacities to probe cellular mechanisms with genetic devices to achieve a more comprehensive understanding of the cell. In this study, we review synthetic biology tools that are being applied to effectively investigate diverse cellular processes, regulatory networks, and multicellular interactions. We also discuss current challenges and future developments in the field that may transform the types of investigation possible in cell biology. © 2017 Mathur et al.

  10. Experimental estimation of regional lung water volume by histogram of pulmonary CT numbers

    International Nuclear Information System (INIS)

    Kato, Shiro; Momoki, Shigeru; Asai, Toshihiko; Shimada, Takeshi; Tamano, Masahiro; Nakamoto, Takaaki; Yoshimura, Masaharu

    1989-01-01

    Both in vitro and in vivo experiments were made to assess the ability of pulmonary CT numbers to quantitatively determine regional water volume in cases of pulmonary congestion or edema associated with left heart failure. In vitro experiment revealed a good linear correlation between the volume of injected water and the determined CT number of polyethylene tube packed with sponge. In the subsequent in vivo experiment with 10 adult mongrel dogs, lung water volumes obtained by pulmonary CT numbers were found to be consistent with the actual volumes. Pulmonary CT numbers for water volume proved to become parameters to quantitatively evaluate pulmonary congestion or edema. (Namekawa, K)

  11. Biology and Mechanics of Blood Flows Part I: Biology

    CERN Document Server

    Thiriet, Marc

    2008-01-01

    Biology and Mechanics of Blood Flows presents the basic knowledge and state-of-the-art techniques necessary to carry out investigations of the cardiovascular system using modeling and simulation. Part I of this two-volume sequence, Biology, addresses the nanoscopic and microscopic scales. The nanoscale corresponds to the scale of biochemical reaction cascades involved in cell adaptation to mechanical stresses among other stimuli. The microscale is the scale of stress-induced tissue remodeling associated with acute or chronic loadings. The cardiovascular system, like any physiological system, has a complicated three-dimensional structure and composition. Its time dependent behavior is regulated, and this complex system has many components. In this authoritative work, the author provides a survey of relevant cell components and processes, with detailed coverage of the electrical and mechanical behaviors of vascular cells, tissues, and organs. Because the behaviors of vascular cells and tissues are tightly coupl...

  12. Control volume based hydrocephalus research; analysis of human data

    Science.gov (United States)

    Cohen, Benjamin; Wei, Timothy; Voorhees, Abram; Madsen, Joseph; Anor, Tomer

    2010-11-01

    Hydrocephalus is a neuropathophysiological disorder primarily diagnosed by increased cerebrospinal fluid volume and pressure within the brain. To date, utilization of clinical measurements have been limited to understanding of the relative amplitude and timing of flow, volume and pressure waveforms; qualitative approaches without a clear framework for meaningful quantitative comparison. Pressure volume models and electric circuit analogs enforce volume conservation principles in terms of pressure. Control volume analysis, through the integral mass and momentum conservation equations, ensures that pressure and volume are accounted for using first principles fluid physics. This approach is able to directly incorporate the diverse measurements obtained by clinicians into a simple, direct and robust mechanics based framework. Clinical data obtained for analysis are discussed along with data processing techniques used to extract terms in the conservation equation. Control volume analysis provides a non-invasive, physics-based approach to extracting pressure information from magnetic resonance velocity data that cannot be measured directly by pressure instrumentation.

  13. Quantitative performance monitoring

    International Nuclear Information System (INIS)

    Heller, A.S.

    1987-01-01

    In the recently published update of NUREG/CR 3883, it was shown that Japanese plants of size and design similar to those in the US have significantly fewer trips in a given year of operation. One way to reduce such imbalance is the efficient use of available plant data. Since plant data are recorded and monitored continuously for management feedback and timely resolution of problems, this data should be actively used to increase the efficiency of operations and, ultimately, for a reduction of plant trips in power plants. A great deal of information is lost, however, if the analytical tools available for the data evaluation are misapplied or not adopted at all. This paper deals with a program developed to use quantitative techniques to monitor personnel performance in an operating power plant. Visual comparisons of ongoing performance with predetermined quantitative performance goals are made. A continuous feedback is provided to management for early detection of adverse trends and timely resolution of problems. Ultimately, costs are reduced through effective resource management and timely decision making

  14. Exploring Nectar Biology To Learn about Pollinators.

    Science.gov (United States)

    LaBare, Kelly M.; Broyles, Steven B.; Klotz, R. Lawrence

    2000-01-01

    Discusses the importance of studying nectar biology. Describes how to extract nectar from various flowers, measure nectar volume, determine sugar concentration, and determine caloric value per nectar sample. These data are then related to hummingbird energetics to determine how many flowers are required to supply the pollinator with its caloric…

  15. Systems Biology of the Fluxome

    Directory of Open Access Journals (Sweden)

    Miguel A. Aon

    2015-07-01

    Full Text Available The advent of high throughput -omics has made the accumulation of comprehensive data sets possible, consisting of changes in genes, transcripts, proteins and metabolites. Systems biology-inspired computational methods for translating metabolomics data into fluxomics provide a direct functional, dynamic readout of metabolic networks. When combined with